diff options
Diffstat (limited to 'Documentation')
90 files changed, 4623 insertions, 1423 deletions
diff --git a/Documentation/00-INDEX b/Documentation/00-INDEX index 5405f7aecefc..8dfc6708a257 100644 --- a/Documentation/00-INDEX +++ b/Documentation/00-INDEX | |||
@@ -130,8 +130,6 @@ edac.txt | |||
130 | - information on EDAC - Error Detection And Correction | 130 | - information on EDAC - Error Detection And Correction |
131 | eisa.txt | 131 | eisa.txt |
132 | - info on EISA bus support. | 132 | - info on EISA bus support. |
133 | exception.txt | ||
134 | - how Linux v2.2 handles exceptions without verify_area etc. | ||
135 | fault-injection/ | 133 | fault-injection/ |
136 | - dir with docs about the fault injection capabilities infrastructure. | 134 | - dir with docs about the fault injection capabilities infrastructure. |
137 | fb/ | 135 | fb/ |
@@ -234,6 +232,8 @@ memory.txt | |||
234 | - info on typical Linux memory problems. | 232 | - info on typical Linux memory problems. |
235 | mips/ | 233 | mips/ |
236 | - directory with info about Linux on MIPS architecture. | 234 | - directory with info about Linux on MIPS architecture. |
235 | mmc/ | ||
236 | - directory with info about the MMC subsystem | ||
237 | mono.txt | 237 | mono.txt |
238 | - how to execute Mono-based .NET binaries with the help of BINFMT_MISC. | 238 | - how to execute Mono-based .NET binaries with the help of BINFMT_MISC. |
239 | mutex-design.txt | 239 | mutex-design.txt |
diff --git a/Documentation/ABI/testing/sysfs-ata b/Documentation/ABI/testing/sysfs-ata new file mode 100644 index 000000000000..0a932155cbba --- /dev/null +++ b/Documentation/ABI/testing/sysfs-ata | |||
@@ -0,0 +1,99 @@ | |||
1 | What: /sys/class/ata_... | ||
2 | Date: August 2008 | ||
3 | Contact: Gwendal Grignou<gwendal@google.com> | ||
4 | Description: | ||
5 | |||
6 | Provide a place in sysfs for storing the ATA topology of the system. This allows | ||
7 | retrieving various information about ATA objects. | ||
8 | |||
9 | Files under /sys/class/ata_port | ||
10 | ------------------------------- | ||
11 | |||
12 | For each port, a directory ataX is created where X is the ata_port_id of | ||
13 | the port. The device parent is the ata host device. | ||
14 | |||
15 | idle_irq (read) | ||
16 | |||
17 | Number of IRQ received by the port while idle [some ata HBA only]. | ||
18 | |||
19 | nr_pmp_links (read) | ||
20 | |||
21 | If a SATA Port Multiplier (PM) is connected, number of link behind it. | ||
22 | |||
23 | Files under /sys/class/ata_link | ||
24 | ------------------------------- | ||
25 | |||
26 | Behind each port, there is a ata_link. If there is a SATA PM in the | ||
27 | topology, 15 ata_link objects are created. | ||
28 | |||
29 | If a link is behind a port, the directory name is linkX, where X is | ||
30 | ata_port_id of the port. | ||
31 | If a link is behind a PM, its name is linkX.Y where X is ata_port_id | ||
32 | of the parent port and Y the PM port. | ||
33 | |||
34 | hw_sata_spd_limit | ||
35 | |||
36 | Maximum speed supported by the connected SATA device. | ||
37 | |||
38 | sata_spd_limit | ||
39 | |||
40 | Maximum speed imposed by libata. | ||
41 | |||
42 | sata_spd | ||
43 | |||
44 | Current speed of the link [1.5, 3Gps,...]. | ||
45 | |||
46 | Files under /sys/class/ata_device | ||
47 | --------------------------------- | ||
48 | |||
49 | Behind each link, up to two ata device are created. | ||
50 | The name of the directory is devX[.Y].Z where: | ||
51 | - X is ata_port_id of the port where the device is connected, | ||
52 | - Y the port of the PM if any, and | ||
53 | - Z the device id: for PATA, there is usually 2 devices [0,1], | ||
54 | only 1 for SATA. | ||
55 | |||
56 | class | ||
57 | Device class. Can be "ata" for disk, "atapi" for packet device, | ||
58 | "pmp" for PM, or "none" if no device was found behind the link. | ||
59 | |||
60 | dma_mode | ||
61 | |||
62 | Transfer modes supported by the device when in DMA mode. | ||
63 | Mostly used by PATA device. | ||
64 | |||
65 | pio_mode | ||
66 | |||
67 | Transfer modes supported by the device when in PIO mode. | ||
68 | Mostly used by PATA device. | ||
69 | |||
70 | xfer_mode | ||
71 | |||
72 | Current transfer mode. | ||
73 | |||
74 | id | ||
75 | |||
76 | Cached result of IDENTIFY command, as described in ATA8 7.16 and 7.17. | ||
77 | Only valid if the device is not a PM. | ||
78 | |||
79 | gscr | ||
80 | |||
81 | Cached result of the dump of PM GSCR register. | ||
82 | Valid registers are: | ||
83 | 0: SATA_PMP_GSCR_PROD_ID, | ||
84 | 1: SATA_PMP_GSCR_REV, | ||
85 | 2: SATA_PMP_GSCR_PORT_INFO, | ||
86 | 32: SATA_PMP_GSCR_ERROR, | ||
87 | 33: SATA_PMP_GSCR_ERROR_EN, | ||
88 | 64: SATA_PMP_GSCR_FEAT, | ||
89 | 96: SATA_PMP_GSCR_FEAT_EN, | ||
90 | 130: SATA_PMP_GSCR_SII_GPIO | ||
91 | Only valid if the device is a PM. | ||
92 | |||
93 | spdn_cnt | ||
94 | |||
95 | Number of time libata decided to lower the speed of link due to errors. | ||
96 | |||
97 | ering | ||
98 | |||
99 | Formatted output of the error ring of the device. | ||
diff --git a/Documentation/ABI/testing/sysfs-devices-power b/Documentation/ABI/testing/sysfs-devices-power index 6123c523bfd7..7628cd1bc36a 100644 --- a/Documentation/ABI/testing/sysfs-devices-power +++ b/Documentation/ABI/testing/sysfs-devices-power | |||
@@ -77,3 +77,91 @@ Description: | |||
77 | devices this attribute is set to "enabled" by bus type code or | 77 | devices this attribute is set to "enabled" by bus type code or |
78 | device drivers and in that cases it should be safe to leave the | 78 | device drivers and in that cases it should be safe to leave the |
79 | default value. | 79 | default value. |
80 | |||
81 | What: /sys/devices/.../power/wakeup_count | ||
82 | Date: September 2010 | ||
83 | Contact: Rafael J. Wysocki <rjw@sisk.pl> | ||
84 | Description: | ||
85 | The /sys/devices/.../wakeup_count attribute contains the number | ||
86 | of signaled wakeup events associated with the device. This | ||
87 | attribute is read-only. If the device is not enabled to wake up | ||
88 | the system from sleep states, this attribute is empty. | ||
89 | |||
90 | What: /sys/devices/.../power/wakeup_active_count | ||
91 | Date: September 2010 | ||
92 | Contact: Rafael J. Wysocki <rjw@sisk.pl> | ||
93 | Description: | ||
94 | The /sys/devices/.../wakeup_active_count attribute contains the | ||
95 | number of times the processing of wakeup events associated with | ||
96 | the device was completed (at the kernel level). This attribute | ||
97 | is read-only. If the device is not enabled to wake up the | ||
98 | system from sleep states, this attribute is empty. | ||
99 | |||
100 | What: /sys/devices/.../power/wakeup_hit_count | ||
101 | Date: September 2010 | ||
102 | Contact: Rafael J. Wysocki <rjw@sisk.pl> | ||
103 | Description: | ||
104 | The /sys/devices/.../wakeup_hit_count attribute contains the | ||
105 | number of times the processing of a wakeup event associated with | ||
106 | the device might prevent the system from entering a sleep state. | ||
107 | This attribute is read-only. If the device is not enabled to | ||
108 | wake up the system from sleep states, this attribute is empty. | ||
109 | |||
110 | What: /sys/devices/.../power/wakeup_active | ||
111 | Date: September 2010 | ||
112 | Contact: Rafael J. Wysocki <rjw@sisk.pl> | ||
113 | Description: | ||
114 | The /sys/devices/.../wakeup_active attribute contains either 1, | ||
115 | or 0, depending on whether or not a wakeup event associated with | ||
116 | the device is being processed (1). This attribute is read-only. | ||
117 | If the device is not enabled to wake up the system from sleep | ||
118 | states, this attribute is empty. | ||
119 | |||
120 | What: /sys/devices/.../power/wakeup_total_time_ms | ||
121 | Date: September 2010 | ||
122 | Contact: Rafael J. Wysocki <rjw@sisk.pl> | ||
123 | Description: | ||
124 | The /sys/devices/.../wakeup_total_time_ms attribute contains | ||
125 | the total time of processing wakeup events associated with the | ||
126 | device, in milliseconds. This attribute is read-only. If the | ||
127 | device is not enabled to wake up the system from sleep states, | ||
128 | this attribute is empty. | ||
129 | |||
130 | What: /sys/devices/.../power/wakeup_max_time_ms | ||
131 | Date: September 2010 | ||
132 | Contact: Rafael J. Wysocki <rjw@sisk.pl> | ||
133 | Description: | ||
134 | The /sys/devices/.../wakeup_max_time_ms attribute contains | ||
135 | the maximum time of processing a single wakeup event associated | ||
136 | with the device, in milliseconds. This attribute is read-only. | ||
137 | If the device is not enabled to wake up the system from sleep | ||
138 | states, this attribute is empty. | ||
139 | |||
140 | What: /sys/devices/.../power/wakeup_last_time_ms | ||
141 | Date: September 2010 | ||
142 | Contact: Rafael J. Wysocki <rjw@sisk.pl> | ||
143 | Description: | ||
144 | The /sys/devices/.../wakeup_last_time_ms attribute contains | ||
145 | the value of the monotonic clock corresponding to the time of | ||
146 | signaling the last wakeup event associated with the device, in | ||
147 | milliseconds. This attribute is read-only. If the device is | ||
148 | not enabled to wake up the system from sleep states, this | ||
149 | attribute is empty. | ||
150 | |||
151 | What: /sys/devices/.../power/autosuspend_delay_ms | ||
152 | Date: September 2010 | ||
153 | Contact: Alan Stern <stern@rowland.harvard.edu> | ||
154 | Description: | ||
155 | The /sys/devices/.../power/autosuspend_delay_ms attribute | ||
156 | contains the autosuspend delay value (in milliseconds). Some | ||
157 | drivers do not want their device to suspend as soon as it | ||
158 | becomes idle at run time; they want the device to remain | ||
159 | inactive for a certain minimum period of time first. That | ||
160 | period is called the autosuspend delay. Negative values will | ||
161 | prevent the device from being suspended at run time (similar | ||
162 | to writing "on" to the power/control attribute). Values >= | ||
163 | 1000 will cause the autosuspend timer expiration to be rounded | ||
164 | up to the nearest second. | ||
165 | |||
166 | Not all drivers support this attribute. If it isn't supported, | ||
167 | attempts to read or write it will yield I/O errors. | ||
diff --git a/Documentation/ABI/testing/sysfs-driver-hid-roccat-pyra b/Documentation/ABI/testing/sysfs-driver-hid-roccat-pyra new file mode 100644 index 000000000000..ad1125b02ff4 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-driver-hid-roccat-pyra | |||
@@ -0,0 +1,98 @@ | |||
1 | What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/actual_cpi | ||
2 | Date: August 2010 | ||
3 | Contact: Stefan Achatz <erazor_de@users.sourceforge.net> | ||
4 | Description: It is possible to switch the cpi setting of the mouse with the | ||
5 | press of a button. | ||
6 | When read, this file returns the raw number of the actual cpi | ||
7 | setting reported by the mouse. This number has to be further | ||
8 | processed to receive the real dpi value. | ||
9 | |||
10 | VALUE DPI | ||
11 | 1 400 | ||
12 | 2 800 | ||
13 | 4 1600 | ||
14 | |||
15 | This file is readonly. | ||
16 | |||
17 | What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/actual_profile | ||
18 | Date: August 2010 | ||
19 | Contact: Stefan Achatz <erazor_de@users.sourceforge.net> | ||
20 | Description: When read, this file returns the number of the actual profile in | ||
21 | range 0-4. | ||
22 | This file is readonly. | ||
23 | |||
24 | What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/firmware_version | ||
25 | Date: August 2010 | ||
26 | Contact: Stefan Achatz <erazor_de@users.sourceforge.net> | ||
27 | Description: When read, this file returns the raw integer version number of the | ||
28 | firmware reported by the mouse. Using the integer value eases | ||
29 | further usage in other programs. To receive the real version | ||
30 | number the decimal point has to be shifted 2 positions to the | ||
31 | left. E.g. a returned value of 138 means 1.38 | ||
32 | This file is readonly. | ||
33 | |||
34 | What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/profile_settings | ||
35 | Date: August 2010 | ||
36 | Contact: Stefan Achatz <erazor_de@users.sourceforge.net> | ||
37 | Description: The mouse can store 5 profiles which can be switched by the | ||
38 | press of a button. A profile is split in settings and buttons. | ||
39 | profile_settings holds informations like resolution, sensitivity | ||
40 | and light effects. | ||
41 | When written, this file lets one write the respective profile | ||
42 | settings back to the mouse. The data has to be 13 bytes long. | ||
43 | The mouse will reject invalid data. | ||
44 | Which profile to write is determined by the profile number | ||
45 | contained in the data. | ||
46 | This file is writeonly. | ||
47 | |||
48 | What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/profile[1-5]_settings | ||
49 | Date: August 2010 | ||
50 | Contact: Stefan Achatz <erazor_de@users.sourceforge.net> | ||
51 | Description: The mouse can store 5 profiles which can be switched by the | ||
52 | press of a button. A profile is split in settings and buttons. | ||
53 | profile_settings holds informations like resolution, sensitivity | ||
54 | and light effects. | ||
55 | When read, these files return the respective profile settings. | ||
56 | The returned data is 13 bytes in size. | ||
57 | This file is readonly. | ||
58 | |||
59 | What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/profile_buttons | ||
60 | Date: August 2010 | ||
61 | Contact: Stefan Achatz <erazor_de@users.sourceforge.net> | ||
62 | Description: The mouse can store 5 profiles which can be switched by the | ||
63 | press of a button. A profile is split in settings and buttons. | ||
64 | profile_buttons holds informations about button layout. | ||
65 | When written, this file lets one write the respective profile | ||
66 | buttons back to the mouse. The data has to be 19 bytes long. | ||
67 | The mouse will reject invalid data. | ||
68 | Which profile to write is determined by the profile number | ||
69 | contained in the data. | ||
70 | This file is writeonly. | ||
71 | |||
72 | What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/profile[1-5]_buttons | ||
73 | Date: August 2010 | ||
74 | Contact: Stefan Achatz <erazor_de@users.sourceforge.net> | ||
75 | Description: The mouse can store 5 profiles which can be switched by the | ||
76 | press of a button. A profile is split in settings and buttons. | ||
77 | profile_buttons holds informations about button layout. | ||
78 | When read, these files return the respective profile buttons. | ||
79 | The returned data is 19 bytes in size. | ||
80 | This file is readonly. | ||
81 | |||
82 | What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/startup_profile | ||
83 | Date: August 2010 | ||
84 | Contact: Stefan Achatz <erazor_de@users.sourceforge.net> | ||
85 | Description: The integer value of this attribute ranges from 0-4. | ||
86 | When read, this attribute returns the number of the profile | ||
87 | that's active when the mouse is powered on. | ||
88 | This file is readonly. | ||
89 | |||
90 | What: /sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/settings | ||
91 | Date: August 2010 | ||
92 | Contact: Stefan Achatz <erazor_de@users.sourceforge.net> | ||
93 | Description: When read, this file returns the settings stored in the mouse. | ||
94 | The size of the data is 3 bytes and holds information on the | ||
95 | startup_profile. | ||
96 | When written, this file lets write settings back to the mouse. | ||
97 | The data has to be 3 bytes long. The mouse will reject invalid | ||
98 | data. | ||
diff --git a/Documentation/ABI/testing/sysfs-module b/Documentation/ABI/testing/sysfs-module new file mode 100644 index 000000000000..cfcec3bffc0a --- /dev/null +++ b/Documentation/ABI/testing/sysfs-module | |||
@@ -0,0 +1,12 @@ | |||
1 | What: /sys/module/pch_phub/drivers/.../pch_mac | ||
2 | Date: August 2010 | ||
3 | KernelVersion: 2.6.35 | ||
4 | Contact: masa-korg@dsn.okisemi.com | ||
5 | Description: Write/read GbE MAC address. | ||
6 | |||
7 | What: /sys/module/pch_phub/drivers/.../pch_firmware | ||
8 | Date: August 2010 | ||
9 | KernelVersion: 2.6.35 | ||
10 | Contact: masa-korg@dsn.okisemi.com | ||
11 | Description: Write/read Option ROM data. | ||
12 | |||
diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power index 2875f1f74a07..194ca446ac28 100644 --- a/Documentation/ABI/testing/sysfs-power +++ b/Documentation/ABI/testing/sysfs-power | |||
@@ -99,9 +99,38 @@ Description: | |||
99 | 99 | ||
100 | dmesg -s 1000000 | grep 'hash matches' | 100 | dmesg -s 1000000 | grep 'hash matches' |
101 | 101 | ||
102 | If you do not get any matches (or they appear to be false | ||
103 | positives), it is possible that the last PM event point | ||
104 | referred to a device created by a loadable kernel module. In | ||
105 | this case cat /sys/power/pm_trace_dev_match (see below) after | ||
106 | your system is started up and the kernel modules are loaded. | ||
107 | |||
102 | CAUTION: Using it will cause your machine's real-time (CMOS) | 108 | CAUTION: Using it will cause your machine's real-time (CMOS) |
103 | clock to be set to a random invalid time after a resume. | 109 | clock to be set to a random invalid time after a resume. |
104 | 110 | ||
111 | What; /sys/power/pm_trace_dev_match | ||
112 | Date: October 2010 | ||
113 | Contact: James Hogan <james@albanarts.com> | ||
114 | Description: | ||
115 | The /sys/power/pm_trace_dev_match file contains the name of the | ||
116 | device associated with the last PM event point saved in the RTC | ||
117 | across reboots when pm_trace has been used. More precisely it | ||
118 | contains the list of current devices (including those | ||
119 | registered by loadable kernel modules since boot) which match | ||
120 | the device hash in the RTC at boot, with a newline after each | ||
121 | one. | ||
122 | |||
123 | The advantage of this file over the hash matches printed to the | ||
124 | kernel log (see /sys/power/pm_trace), is that it includes | ||
125 | devices created after boot by loadable kernel modules. | ||
126 | |||
127 | Due to the small hash size necessary to fit in the RTC, it is | ||
128 | possible that more than one device matches the hash, in which | ||
129 | case further investigation is required to determine which | ||
130 | device is causing the problem. Note that genuine RTC clock | ||
131 | values (such as when pm_trace has not been used), can still | ||
132 | match a device and output it's name here. | ||
133 | |||
105 | What: /sys/power/pm_async | 134 | What: /sys/power/pm_async |
106 | Date: January 2009 | 135 | Date: January 2009 |
107 | Contact: Rafael J. Wysocki <rjw@sisk.pl> | 136 | Contact: Rafael J. Wysocki <rjw@sisk.pl> |
diff --git a/Documentation/DMA-API-HOWTO.txt b/Documentation/DMA-API-HOWTO.txt index 98ce51796f71..d568bc235bc0 100644 --- a/Documentation/DMA-API-HOWTO.txt +++ b/Documentation/DMA-API-HOWTO.txt | |||
@@ -738,21 +738,31 @@ to "Closing". | |||
738 | CONFIG_NEED_SG_DMA_LENGTH if the architecture supports IOMMUs | 738 | CONFIG_NEED_SG_DMA_LENGTH if the architecture supports IOMMUs |
739 | (including software IOMMU). | 739 | (including software IOMMU). |
740 | 740 | ||
741 | 2) ARCH_KMALLOC_MINALIGN | 741 | 2) ARCH_DMA_MINALIGN |
742 | 742 | ||
743 | Architectures must ensure that kmalloc'ed buffer is | 743 | Architectures must ensure that kmalloc'ed buffer is |
744 | DMA-safe. Drivers and subsystems depend on it. If an architecture | 744 | DMA-safe. Drivers and subsystems depend on it. If an architecture |
745 | isn't fully DMA-coherent (i.e. hardware doesn't ensure that data in | 745 | isn't fully DMA-coherent (i.e. hardware doesn't ensure that data in |
746 | the CPU cache is identical to data in main memory), | 746 | the CPU cache is identical to data in main memory), |
747 | ARCH_KMALLOC_MINALIGN must be set so that the memory allocator | 747 | ARCH_DMA_MINALIGN must be set so that the memory allocator |
748 | makes sure that kmalloc'ed buffer doesn't share a cache line with | 748 | makes sure that kmalloc'ed buffer doesn't share a cache line with |
749 | the others. See arch/arm/include/asm/cache.h as an example. | 749 | the others. See arch/arm/include/asm/cache.h as an example. |
750 | 750 | ||
751 | Note that ARCH_KMALLOC_MINALIGN is about DMA memory alignment | 751 | Note that ARCH_DMA_MINALIGN is about DMA memory alignment |
752 | constraints. You don't need to worry about the architecture data | 752 | constraints. You don't need to worry about the architecture data |
753 | alignment constraints (e.g. the alignment constraints about 64-bit | 753 | alignment constraints (e.g. the alignment constraints about 64-bit |
754 | objects). | 754 | objects). |
755 | 755 | ||
756 | 3) Supporting multiple types of IOMMUs | ||
757 | |||
758 | If your architecture needs to support multiple types of IOMMUs, you | ||
759 | can use include/linux/asm-generic/dma-mapping-common.h. It's a | ||
760 | library to support the DMA API with multiple types of IOMMUs. Lots | ||
761 | of architectures (x86, powerpc, sh, alpha, ia64, microblaze and | ||
762 | sparc) use it. Choose one to see how it can be used. If you need to | ||
763 | support multiple types of IOMMUs in a single system, the example of | ||
764 | x86 or powerpc helps. | ||
765 | |||
756 | Closing | 766 | Closing |
757 | 767 | ||
758 | This document, and the API itself, would not be in its current | 768 | This document, and the API itself, would not be in its current |
diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt index 05e2ae236865..fe2326906610 100644 --- a/Documentation/DMA-API.txt +++ b/Documentation/DMA-API.txt | |||
@@ -456,12 +456,6 @@ be identical to those passed in (and returned by | |||
456 | dma_alloc_noncoherent()). | 456 | dma_alloc_noncoherent()). |
457 | 457 | ||
458 | int | 458 | int |
459 | dma_is_consistent(struct device *dev, dma_addr_t dma_handle) | ||
460 | |||
461 | Returns true if the device dev is performing consistent DMA on the memory | ||
462 | area pointed to by the dma_handle. | ||
463 | |||
464 | int | ||
465 | dma_get_cache_alignment(void) | 459 | dma_get_cache_alignment(void) |
466 | 460 | ||
467 | Returns the processor cache alignment. This is the absolute minimum | 461 | Returns the processor cache alignment. This is the absolute minimum |
diff --git a/Documentation/DocBook/80211.tmpl b/Documentation/DocBook/80211.tmpl new file mode 100644 index 000000000000..19a1210c2530 --- /dev/null +++ b/Documentation/DocBook/80211.tmpl | |||
@@ -0,0 +1,495 @@ | |||
1 | <?xml version="1.0" encoding="UTF-8"?> | ||
2 | <!DOCTYPE set PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN" | ||
3 | "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []> | ||
4 | <set> | ||
5 | <setinfo> | ||
6 | <title>The 802.11 subsystems – for kernel developers</title> | ||
7 | <subtitle> | ||
8 | Explaining wireless 802.11 networking in the Linux kernel | ||
9 | </subtitle> | ||
10 | |||
11 | <copyright> | ||
12 | <year>2007-2009</year> | ||
13 | <holder>Johannes Berg</holder> | ||
14 | </copyright> | ||
15 | |||
16 | <authorgroup> | ||
17 | <author> | ||
18 | <firstname>Johannes</firstname> | ||
19 | <surname>Berg</surname> | ||
20 | <affiliation> | ||
21 | <address><email>johannes@sipsolutions.net</email></address> | ||
22 | </affiliation> | ||
23 | </author> | ||
24 | </authorgroup> | ||
25 | |||
26 | <legalnotice> | ||
27 | <para> | ||
28 | This documentation is free software; you can redistribute | ||
29 | it and/or modify it under the terms of the GNU General Public | ||
30 | License version 2 as published by the Free Software Foundation. | ||
31 | </para> | ||
32 | <para> | ||
33 | This documentation is distributed in the hope that it will be | ||
34 | useful, but WITHOUT ANY WARRANTY; without even the implied | ||
35 | warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | ||
36 | See the GNU General Public License for more details. | ||
37 | </para> | ||
38 | <para> | ||
39 | You should have received a copy of the GNU General Public | ||
40 | License along with this documentation; if not, write to the Free | ||
41 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, | ||
42 | MA 02111-1307 USA | ||
43 | </para> | ||
44 | <para> | ||
45 | For more details see the file COPYING in the source | ||
46 | distribution of Linux. | ||
47 | </para> | ||
48 | </legalnotice> | ||
49 | |||
50 | <abstract> | ||
51 | <para> | ||
52 | These books attempt to give a description of the | ||
53 | various subsystems that play a role in 802.11 wireless | ||
54 | networking in Linux. Since these books are for kernel | ||
55 | developers they attempts to document the structures | ||
56 | and functions used in the kernel as well as giving a | ||
57 | higher-level overview. | ||
58 | </para> | ||
59 | <para> | ||
60 | The reader is expected to be familiar with the 802.11 | ||
61 | standard as published by the IEEE in 802.11-2007 (or | ||
62 | possibly later versions). References to this standard | ||
63 | will be given as "802.11-2007 8.1.5". | ||
64 | </para> | ||
65 | </abstract> | ||
66 | </setinfo> | ||
67 | <book id="cfg80211-developers-guide"> | ||
68 | <bookinfo> | ||
69 | <title>The cfg80211 subsystem</title> | ||
70 | |||
71 | <abstract> | ||
72 | !Pinclude/net/cfg80211.h Introduction | ||
73 | </abstract> | ||
74 | </bookinfo> | ||
75 | <chapter> | ||
76 | <title>Device registration</title> | ||
77 | !Pinclude/net/cfg80211.h Device registration | ||
78 | !Finclude/net/cfg80211.h ieee80211_band | ||
79 | !Finclude/net/cfg80211.h ieee80211_channel_flags | ||
80 | !Finclude/net/cfg80211.h ieee80211_channel | ||
81 | !Finclude/net/cfg80211.h ieee80211_rate_flags | ||
82 | !Finclude/net/cfg80211.h ieee80211_rate | ||
83 | !Finclude/net/cfg80211.h ieee80211_sta_ht_cap | ||
84 | !Finclude/net/cfg80211.h ieee80211_supported_band | ||
85 | !Finclude/net/cfg80211.h cfg80211_signal_type | ||
86 | !Finclude/net/cfg80211.h wiphy_params_flags | ||
87 | !Finclude/net/cfg80211.h wiphy_flags | ||
88 | !Finclude/net/cfg80211.h wiphy | ||
89 | !Finclude/net/cfg80211.h wireless_dev | ||
90 | !Finclude/net/cfg80211.h wiphy_new | ||
91 | !Finclude/net/cfg80211.h wiphy_register | ||
92 | !Finclude/net/cfg80211.h wiphy_unregister | ||
93 | !Finclude/net/cfg80211.h wiphy_free | ||
94 | |||
95 | !Finclude/net/cfg80211.h wiphy_name | ||
96 | !Finclude/net/cfg80211.h wiphy_dev | ||
97 | !Finclude/net/cfg80211.h wiphy_priv | ||
98 | !Finclude/net/cfg80211.h priv_to_wiphy | ||
99 | !Finclude/net/cfg80211.h set_wiphy_dev | ||
100 | !Finclude/net/cfg80211.h wdev_priv | ||
101 | </chapter> | ||
102 | <chapter> | ||
103 | <title>Actions and configuration</title> | ||
104 | !Pinclude/net/cfg80211.h Actions and configuration | ||
105 | !Finclude/net/cfg80211.h cfg80211_ops | ||
106 | !Finclude/net/cfg80211.h vif_params | ||
107 | !Finclude/net/cfg80211.h key_params | ||
108 | !Finclude/net/cfg80211.h survey_info_flags | ||
109 | !Finclude/net/cfg80211.h survey_info | ||
110 | !Finclude/net/cfg80211.h beacon_parameters | ||
111 | !Finclude/net/cfg80211.h plink_actions | ||
112 | !Finclude/net/cfg80211.h station_parameters | ||
113 | !Finclude/net/cfg80211.h station_info_flags | ||
114 | !Finclude/net/cfg80211.h rate_info_flags | ||
115 | !Finclude/net/cfg80211.h rate_info | ||
116 | !Finclude/net/cfg80211.h station_info | ||
117 | !Finclude/net/cfg80211.h monitor_flags | ||
118 | !Finclude/net/cfg80211.h mpath_info_flags | ||
119 | !Finclude/net/cfg80211.h mpath_info | ||
120 | !Finclude/net/cfg80211.h bss_parameters | ||
121 | !Finclude/net/cfg80211.h ieee80211_txq_params | ||
122 | !Finclude/net/cfg80211.h cfg80211_crypto_settings | ||
123 | !Finclude/net/cfg80211.h cfg80211_auth_request | ||
124 | !Finclude/net/cfg80211.h cfg80211_assoc_request | ||
125 | !Finclude/net/cfg80211.h cfg80211_deauth_request | ||
126 | !Finclude/net/cfg80211.h cfg80211_disassoc_request | ||
127 | !Finclude/net/cfg80211.h cfg80211_ibss_params | ||
128 | !Finclude/net/cfg80211.h cfg80211_connect_params | ||
129 | !Finclude/net/cfg80211.h cfg80211_pmksa | ||
130 | !Finclude/net/cfg80211.h cfg80211_send_rx_auth | ||
131 | !Finclude/net/cfg80211.h cfg80211_send_auth_timeout | ||
132 | !Finclude/net/cfg80211.h __cfg80211_auth_canceled | ||
133 | !Finclude/net/cfg80211.h cfg80211_send_rx_assoc | ||
134 | !Finclude/net/cfg80211.h cfg80211_send_assoc_timeout | ||
135 | !Finclude/net/cfg80211.h cfg80211_send_deauth | ||
136 | !Finclude/net/cfg80211.h __cfg80211_send_deauth | ||
137 | !Finclude/net/cfg80211.h cfg80211_send_disassoc | ||
138 | !Finclude/net/cfg80211.h __cfg80211_send_disassoc | ||
139 | !Finclude/net/cfg80211.h cfg80211_ibss_joined | ||
140 | !Finclude/net/cfg80211.h cfg80211_connect_result | ||
141 | !Finclude/net/cfg80211.h cfg80211_roamed | ||
142 | !Finclude/net/cfg80211.h cfg80211_disconnected | ||
143 | !Finclude/net/cfg80211.h cfg80211_ready_on_channel | ||
144 | !Finclude/net/cfg80211.h cfg80211_remain_on_channel_expired | ||
145 | !Finclude/net/cfg80211.h cfg80211_new_sta | ||
146 | !Finclude/net/cfg80211.h cfg80211_rx_mgmt | ||
147 | !Finclude/net/cfg80211.h cfg80211_mgmt_tx_status | ||
148 | !Finclude/net/cfg80211.h cfg80211_cqm_rssi_notify | ||
149 | !Finclude/net/cfg80211.h cfg80211_michael_mic_failure | ||
150 | </chapter> | ||
151 | <chapter> | ||
152 | <title>Scanning and BSS list handling</title> | ||
153 | !Pinclude/net/cfg80211.h Scanning and BSS list handling | ||
154 | !Finclude/net/cfg80211.h cfg80211_ssid | ||
155 | !Finclude/net/cfg80211.h cfg80211_scan_request | ||
156 | !Finclude/net/cfg80211.h cfg80211_scan_done | ||
157 | !Finclude/net/cfg80211.h cfg80211_bss | ||
158 | !Finclude/net/cfg80211.h cfg80211_inform_bss_frame | ||
159 | !Finclude/net/cfg80211.h cfg80211_inform_bss | ||
160 | !Finclude/net/cfg80211.h cfg80211_unlink_bss | ||
161 | !Finclude/net/cfg80211.h cfg80211_find_ie | ||
162 | !Finclude/net/cfg80211.h ieee80211_bss_get_ie | ||
163 | </chapter> | ||
164 | <chapter> | ||
165 | <title>Utility functions</title> | ||
166 | !Pinclude/net/cfg80211.h Utility functions | ||
167 | !Finclude/net/cfg80211.h ieee80211_channel_to_frequency | ||
168 | !Finclude/net/cfg80211.h ieee80211_frequency_to_channel | ||
169 | !Finclude/net/cfg80211.h ieee80211_get_channel | ||
170 | !Finclude/net/cfg80211.h ieee80211_get_response_rate | ||
171 | !Finclude/net/cfg80211.h ieee80211_hdrlen | ||
172 | !Finclude/net/cfg80211.h ieee80211_get_hdrlen_from_skb | ||
173 | !Finclude/net/cfg80211.h ieee80211_radiotap_iterator | ||
174 | </chapter> | ||
175 | <chapter> | ||
176 | <title>Data path helpers</title> | ||
177 | !Pinclude/net/cfg80211.h Data path helpers | ||
178 | !Finclude/net/cfg80211.h ieee80211_data_to_8023 | ||
179 | !Finclude/net/cfg80211.h ieee80211_data_from_8023 | ||
180 | !Finclude/net/cfg80211.h ieee80211_amsdu_to_8023s | ||
181 | !Finclude/net/cfg80211.h cfg80211_classify8021d | ||
182 | </chapter> | ||
183 | <chapter> | ||
184 | <title>Regulatory enforcement infrastructure</title> | ||
185 | !Pinclude/net/cfg80211.h Regulatory enforcement infrastructure | ||
186 | !Finclude/net/cfg80211.h regulatory_hint | ||
187 | !Finclude/net/cfg80211.h wiphy_apply_custom_regulatory | ||
188 | !Finclude/net/cfg80211.h freq_reg_info | ||
189 | </chapter> | ||
190 | <chapter> | ||
191 | <title>RFkill integration</title> | ||
192 | !Pinclude/net/cfg80211.h RFkill integration | ||
193 | !Finclude/net/cfg80211.h wiphy_rfkill_set_hw_state | ||
194 | !Finclude/net/cfg80211.h wiphy_rfkill_start_polling | ||
195 | !Finclude/net/cfg80211.h wiphy_rfkill_stop_polling | ||
196 | </chapter> | ||
197 | <chapter> | ||
198 | <title>Test mode</title> | ||
199 | !Pinclude/net/cfg80211.h Test mode | ||
200 | !Finclude/net/cfg80211.h cfg80211_testmode_alloc_reply_skb | ||
201 | !Finclude/net/cfg80211.h cfg80211_testmode_reply | ||
202 | !Finclude/net/cfg80211.h cfg80211_testmode_alloc_event_skb | ||
203 | !Finclude/net/cfg80211.h cfg80211_testmode_event | ||
204 | </chapter> | ||
205 | </book> | ||
206 | <book id="mac80211-developers-guide"> | ||
207 | <bookinfo> | ||
208 | <title>The mac80211 subsystem</title> | ||
209 | <abstract> | ||
210 | !Pinclude/net/mac80211.h Introduction | ||
211 | !Pinclude/net/mac80211.h Warning | ||
212 | </abstract> | ||
213 | </bookinfo> | ||
214 | |||
215 | <toc></toc> | ||
216 | |||
217 | <!-- | ||
218 | Generally, this document shall be ordered by increasing complexity. | ||
219 | It is important to note that readers should be able to read only | ||
220 | the first few sections to get a working driver and only advanced | ||
221 | usage should require reading the full document. | ||
222 | --> | ||
223 | |||
224 | <part> | ||
225 | <title>The basic mac80211 driver interface</title> | ||
226 | <partintro> | ||
227 | <para> | ||
228 | You should read and understand the information contained | ||
229 | within this part of the book while implementing a driver. | ||
230 | In some chapters, advanced usage is noted, that may be | ||
231 | skipped at first. | ||
232 | </para> | ||
233 | <para> | ||
234 | This part of the book only covers station and monitor mode | ||
235 | functionality, additional information required to implement | ||
236 | the other modes is covered in the second part of the book. | ||
237 | </para> | ||
238 | </partintro> | ||
239 | |||
240 | <chapter id="basics"> | ||
241 | <title>Basic hardware handling</title> | ||
242 | <para>TBD</para> | ||
243 | <para> | ||
244 | This chapter shall contain information on getting a hw | ||
245 | struct allocated and registered with mac80211. | ||
246 | </para> | ||
247 | <para> | ||
248 | Since it is required to allocate rates/modes before registering | ||
249 | a hw struct, this chapter shall also contain information on setting | ||
250 | up the rate/mode structs. | ||
251 | </para> | ||
252 | <para> | ||
253 | Additionally, some discussion about the callbacks and | ||
254 | the general programming model should be in here, including | ||
255 | the definition of ieee80211_ops which will be referred to | ||
256 | a lot. | ||
257 | </para> | ||
258 | <para> | ||
259 | Finally, a discussion of hardware capabilities should be done | ||
260 | with references to other parts of the book. | ||
261 | </para> | ||
262 | <!-- intentionally multiple !F lines to get proper order --> | ||
263 | !Finclude/net/mac80211.h ieee80211_hw | ||
264 | !Finclude/net/mac80211.h ieee80211_hw_flags | ||
265 | !Finclude/net/mac80211.h SET_IEEE80211_DEV | ||
266 | !Finclude/net/mac80211.h SET_IEEE80211_PERM_ADDR | ||
267 | !Finclude/net/mac80211.h ieee80211_ops | ||
268 | !Finclude/net/mac80211.h ieee80211_alloc_hw | ||
269 | !Finclude/net/mac80211.h ieee80211_register_hw | ||
270 | !Finclude/net/mac80211.h ieee80211_get_tx_led_name | ||
271 | !Finclude/net/mac80211.h ieee80211_get_rx_led_name | ||
272 | !Finclude/net/mac80211.h ieee80211_get_assoc_led_name | ||
273 | !Finclude/net/mac80211.h ieee80211_get_radio_led_name | ||
274 | !Finclude/net/mac80211.h ieee80211_unregister_hw | ||
275 | !Finclude/net/mac80211.h ieee80211_free_hw | ||
276 | </chapter> | ||
277 | |||
278 | <chapter id="phy-handling"> | ||
279 | <title>PHY configuration</title> | ||
280 | <para>TBD</para> | ||
281 | <para> | ||
282 | This chapter should describe PHY handling including | ||
283 | start/stop callbacks and the various structures used. | ||
284 | </para> | ||
285 | !Finclude/net/mac80211.h ieee80211_conf | ||
286 | !Finclude/net/mac80211.h ieee80211_conf_flags | ||
287 | </chapter> | ||
288 | |||
289 | <chapter id="iface-handling"> | ||
290 | <title>Virtual interfaces</title> | ||
291 | <para>TBD</para> | ||
292 | <para> | ||
293 | This chapter should describe virtual interface basics | ||
294 | that are relevant to the driver (VLANs, MGMT etc are not.) | ||
295 | It should explain the use of the add_iface/remove_iface | ||
296 | callbacks as well as the interface configuration callbacks. | ||
297 | </para> | ||
298 | <para>Things related to AP mode should be discussed there.</para> | ||
299 | <para> | ||
300 | Things related to supporting multiple interfaces should be | ||
301 | in the appropriate chapter, a BIG FAT note should be here about | ||
302 | this though and the recommendation to allow only a single | ||
303 | interface in STA mode at first! | ||
304 | </para> | ||
305 | !Finclude/net/mac80211.h ieee80211_vif | ||
306 | </chapter> | ||
307 | |||
308 | <chapter id="rx-tx"> | ||
309 | <title>Receive and transmit processing</title> | ||
310 | <sect1> | ||
311 | <title>what should be here</title> | ||
312 | <para>TBD</para> | ||
313 | <para> | ||
314 | This should describe the receive and transmit | ||
315 | paths in mac80211/the drivers as well as | ||
316 | transmit status handling. | ||
317 | </para> | ||
318 | </sect1> | ||
319 | <sect1> | ||
320 | <title>Frame format</title> | ||
321 | !Pinclude/net/mac80211.h Frame format | ||
322 | </sect1> | ||
323 | <sect1> | ||
324 | <title>Packet alignment</title> | ||
325 | !Pnet/mac80211/rx.c Packet alignment | ||
326 | </sect1> | ||
327 | <sect1> | ||
328 | <title>Calling into mac80211 from interrupts</title> | ||
329 | !Pinclude/net/mac80211.h Calling mac80211 from interrupts | ||
330 | </sect1> | ||
331 | <sect1> | ||
332 | <title>functions/definitions</title> | ||
333 | !Finclude/net/mac80211.h ieee80211_rx_status | ||
334 | !Finclude/net/mac80211.h mac80211_rx_flags | ||
335 | !Finclude/net/mac80211.h ieee80211_tx_info | ||
336 | !Finclude/net/mac80211.h ieee80211_rx | ||
337 | !Finclude/net/mac80211.h ieee80211_rx_irqsafe | ||
338 | !Finclude/net/mac80211.h ieee80211_tx_status | ||
339 | !Finclude/net/mac80211.h ieee80211_tx_status_irqsafe | ||
340 | !Finclude/net/mac80211.h ieee80211_rts_get | ||
341 | !Finclude/net/mac80211.h ieee80211_rts_duration | ||
342 | !Finclude/net/mac80211.h ieee80211_ctstoself_get | ||
343 | !Finclude/net/mac80211.h ieee80211_ctstoself_duration | ||
344 | !Finclude/net/mac80211.h ieee80211_generic_frame_duration | ||
345 | !Finclude/net/mac80211.h ieee80211_wake_queue | ||
346 | !Finclude/net/mac80211.h ieee80211_stop_queue | ||
347 | !Finclude/net/mac80211.h ieee80211_wake_queues | ||
348 | !Finclude/net/mac80211.h ieee80211_stop_queues | ||
349 | </sect1> | ||
350 | </chapter> | ||
351 | |||
352 | <chapter id="filters"> | ||
353 | <title>Frame filtering</title> | ||
354 | !Pinclude/net/mac80211.h Frame filtering | ||
355 | !Finclude/net/mac80211.h ieee80211_filter_flags | ||
356 | </chapter> | ||
357 | </part> | ||
358 | |||
359 | <part id="advanced"> | ||
360 | <title>Advanced driver interface</title> | ||
361 | <partintro> | ||
362 | <para> | ||
363 | Information contained within this part of the book is | ||
364 | of interest only for advanced interaction of mac80211 | ||
365 | with drivers to exploit more hardware capabilities and | ||
366 | improve performance. | ||
367 | </para> | ||
368 | </partintro> | ||
369 | |||
370 | <chapter id="hardware-crypto-offload"> | ||
371 | <title>Hardware crypto acceleration</title> | ||
372 | !Pinclude/net/mac80211.h Hardware crypto acceleration | ||
373 | <!-- intentionally multiple !F lines to get proper order --> | ||
374 | !Finclude/net/mac80211.h set_key_cmd | ||
375 | !Finclude/net/mac80211.h ieee80211_key_conf | ||
376 | !Finclude/net/mac80211.h ieee80211_key_flags | ||
377 | </chapter> | ||
378 | |||
379 | <chapter id="powersave"> | ||
380 | <title>Powersave support</title> | ||
381 | !Pinclude/net/mac80211.h Powersave support | ||
382 | </chapter> | ||
383 | |||
384 | <chapter id="beacon-filter"> | ||
385 | <title>Beacon filter support</title> | ||
386 | !Pinclude/net/mac80211.h Beacon filter support | ||
387 | !Finclude/net/mac80211.h ieee80211_beacon_loss | ||
388 | </chapter> | ||
389 | |||
390 | <chapter id="qos"> | ||
391 | <title>Multiple queues and QoS support</title> | ||
392 | <para>TBD</para> | ||
393 | !Finclude/net/mac80211.h ieee80211_tx_queue_params | ||
394 | </chapter> | ||
395 | |||
396 | <chapter id="AP"> | ||
397 | <title>Access point mode support</title> | ||
398 | <para>TBD</para> | ||
399 | <para>Some parts of the if_conf should be discussed here instead</para> | ||
400 | <para> | ||
401 | Insert notes about VLAN interfaces with hw crypto here or | ||
402 | in the hw crypto chapter. | ||
403 | </para> | ||
404 | !Finclude/net/mac80211.h ieee80211_get_buffered_bc | ||
405 | !Finclude/net/mac80211.h ieee80211_beacon_get | ||
406 | </chapter> | ||
407 | |||
408 | <chapter id="multi-iface"> | ||
409 | <title>Supporting multiple virtual interfaces</title> | ||
410 | <para>TBD</para> | ||
411 | <para> | ||
412 | Note: WDS with identical MAC address should almost always be OK | ||
413 | </para> | ||
414 | <para> | ||
415 | Insert notes about having multiple virtual interfaces with | ||
416 | different MAC addresses here, note which configurations are | ||
417 | supported by mac80211, add notes about supporting hw crypto | ||
418 | with it. | ||
419 | </para> | ||
420 | </chapter> | ||
421 | |||
422 | <chapter id="hardware-scan-offload"> | ||
423 | <title>Hardware scan offload</title> | ||
424 | <para>TBD</para> | ||
425 | !Finclude/net/mac80211.h ieee80211_scan_completed | ||
426 | </chapter> | ||
427 | </part> | ||
428 | |||
429 | <part id="rate-control"> | ||
430 | <title>Rate control interface</title> | ||
431 | <partintro> | ||
432 | <para>TBD</para> | ||
433 | <para> | ||
434 | This part of the book describes the rate control algorithm | ||
435 | interface and how it relates to mac80211 and drivers. | ||
436 | </para> | ||
437 | </partintro> | ||
438 | <chapter id="dummy"> | ||
439 | <title>dummy chapter</title> | ||
440 | <para>TBD</para> | ||
441 | </chapter> | ||
442 | </part> | ||
443 | |||
444 | <part id="internal"> | ||
445 | <title>Internals</title> | ||
446 | <partintro> | ||
447 | <para>TBD</para> | ||
448 | <para> | ||
449 | This part of the book describes mac80211 internals. | ||
450 | </para> | ||
451 | </partintro> | ||
452 | |||
453 | <chapter id="key-handling"> | ||
454 | <title>Key handling</title> | ||
455 | <sect1> | ||
456 | <title>Key handling basics</title> | ||
457 | !Pnet/mac80211/key.c Key handling basics | ||
458 | </sect1> | ||
459 | <sect1> | ||
460 | <title>MORE TBD</title> | ||
461 | <para>TBD</para> | ||
462 | </sect1> | ||
463 | </chapter> | ||
464 | |||
465 | <chapter id="rx-processing"> | ||
466 | <title>Receive processing</title> | ||
467 | <para>TBD</para> | ||
468 | </chapter> | ||
469 | |||
470 | <chapter id="tx-processing"> | ||
471 | <title>Transmit processing</title> | ||
472 | <para>TBD</para> | ||
473 | </chapter> | ||
474 | |||
475 | <chapter id="sta-info"> | ||
476 | <title>Station info handling</title> | ||
477 | <sect1> | ||
478 | <title>Programming information</title> | ||
479 | !Fnet/mac80211/sta_info.h sta_info | ||
480 | !Fnet/mac80211/sta_info.h ieee80211_sta_info_flags | ||
481 | </sect1> | ||
482 | <sect1> | ||
483 | <title>STA information lifetime rules</title> | ||
484 | !Pnet/mac80211/sta_info.c STA information lifetime rules | ||
485 | </sect1> | ||
486 | </chapter> | ||
487 | |||
488 | <chapter id="synchronisation"> | ||
489 | <title>Synchronisation</title> | ||
490 | <para>TBD</para> | ||
491 | <para>Locking, lots of RCU</para> | ||
492 | </chapter> | ||
493 | </part> | ||
494 | </book> | ||
495 | </set> | ||
diff --git a/Documentation/DocBook/Makefile b/Documentation/DocBook/Makefile index 4b603c5c3cc1..8b6e00a71034 100644 --- a/Documentation/DocBook/Makefile +++ b/Documentation/DocBook/Makefile | |||
@@ -12,7 +12,7 @@ DOCBOOKS := z8530book.xml mcabook.xml device-drivers.xml \ | |||
12 | kernel-api.xml filesystems.xml lsm.xml usb.xml kgdb.xml \ | 12 | kernel-api.xml filesystems.xml lsm.xml usb.xml kgdb.xml \ |
13 | gadget.xml libata.xml mtdnand.xml librs.xml rapidio.xml \ | 13 | gadget.xml libata.xml mtdnand.xml librs.xml rapidio.xml \ |
14 | genericirq.xml s390-drivers.xml uio-howto.xml scsi.xml \ | 14 | genericirq.xml s390-drivers.xml uio-howto.xml scsi.xml \ |
15 | mac80211.xml debugobjects.xml sh.xml regulator.xml \ | 15 | 80211.xml debugobjects.xml sh.xml regulator.xml \ |
16 | alsa-driver-api.xml writing-an-alsa-driver.xml \ | 16 | alsa-driver-api.xml writing-an-alsa-driver.xml \ |
17 | tracepoint.xml media.xml drm.xml | 17 | tracepoint.xml media.xml drm.xml |
18 | 18 | ||
@@ -35,7 +35,7 @@ PS_METHOD = $(prefer-db2x) | |||
35 | PHONY += xmldocs sgmldocs psdocs pdfdocs htmldocs mandocs installmandocs cleandocs xmldoclinks | 35 | PHONY += xmldocs sgmldocs psdocs pdfdocs htmldocs mandocs installmandocs cleandocs xmldoclinks |
36 | 36 | ||
37 | BOOKS := $(addprefix $(obj)/,$(DOCBOOKS)) | 37 | BOOKS := $(addprefix $(obj)/,$(DOCBOOKS)) |
38 | xmldocs: $(BOOKS) xmldoclinks | 38 | xmldocs: $(BOOKS) |
39 | sgmldocs: xmldocs | 39 | sgmldocs: xmldocs |
40 | 40 | ||
41 | PS := $(patsubst %.xml, %.ps, $(BOOKS)) | 41 | PS := $(patsubst %.xml, %.ps, $(BOOKS)) |
@@ -95,7 +95,7 @@ define rule_docproc | |||
95 | ) > $(dir $@).$(notdir $@).cmd | 95 | ) > $(dir $@).$(notdir $@).cmd |
96 | endef | 96 | endef |
97 | 97 | ||
98 | %.xml: %.tmpl FORCE | 98 | %.xml: %.tmpl xmldoclinks FORCE |
99 | $(call if_changed_rule,docproc) | 99 | $(call if_changed_rule,docproc) |
100 | 100 | ||
101 | ### | 101 | ### |
diff --git a/Documentation/DocBook/device-drivers.tmpl b/Documentation/DocBook/device-drivers.tmpl index ecd35e9d4410..feca0758391e 100644 --- a/Documentation/DocBook/device-drivers.tmpl +++ b/Documentation/DocBook/device-drivers.tmpl | |||
@@ -46,7 +46,6 @@ | |||
46 | 46 | ||
47 | <sect1><title>Atomic and pointer manipulation</title> | 47 | <sect1><title>Atomic and pointer manipulation</title> |
48 | !Iarch/x86/include/asm/atomic.h | 48 | !Iarch/x86/include/asm/atomic.h |
49 | !Iarch/x86/include/asm/unaligned.h | ||
50 | </sect1> | 49 | </sect1> |
51 | 50 | ||
52 | <sect1><title>Delaying, scheduling, and timer routines</title> | 51 | <sect1><title>Delaying, scheduling, and timer routines</title> |
diff --git a/Documentation/DocBook/drm.tmpl b/Documentation/DocBook/drm.tmpl index 910c923a9b86..2861055afd7a 100644 --- a/Documentation/DocBook/drm.tmpl +++ b/Documentation/DocBook/drm.tmpl | |||
@@ -136,6 +136,7 @@ | |||
136 | #ifdef CONFIG_COMPAT | 136 | #ifdef CONFIG_COMPAT |
137 | .compat_ioctl = i915_compat_ioctl, | 137 | .compat_ioctl = i915_compat_ioctl, |
138 | #endif | 138 | #endif |
139 | .llseek = noop_llseek, | ||
139 | }, | 140 | }, |
140 | .pci_driver = { | 141 | .pci_driver = { |
141 | .name = DRIVER_NAME, | 142 | .name = DRIVER_NAME, |
diff --git a/Documentation/DocBook/genericirq.tmpl b/Documentation/DocBook/genericirq.tmpl index 1448b33fd222..fb10fd08c05c 100644 --- a/Documentation/DocBook/genericirq.tmpl +++ b/Documentation/DocBook/genericirq.tmpl | |||
@@ -28,7 +28,7 @@ | |||
28 | </authorgroup> | 28 | </authorgroup> |
29 | 29 | ||
30 | <copyright> | 30 | <copyright> |
31 | <year>2005-2006</year> | 31 | <year>2005-2010</year> |
32 | <holder>Thomas Gleixner</holder> | 32 | <holder>Thomas Gleixner</holder> |
33 | </copyright> | 33 | </copyright> |
34 | <copyright> | 34 | <copyright> |
@@ -100,6 +100,10 @@ | |||
100 | <listitem><para>Edge type</para></listitem> | 100 | <listitem><para>Edge type</para></listitem> |
101 | <listitem><para>Simple type</para></listitem> | 101 | <listitem><para>Simple type</para></listitem> |
102 | </itemizedlist> | 102 | </itemizedlist> |
103 | During the implementation we identified another type: | ||
104 | <itemizedlist> | ||
105 | <listitem><para>Fast EOI type</para></listitem> | ||
106 | </itemizedlist> | ||
103 | In the SMP world of the __do_IRQ() super-handler another type | 107 | In the SMP world of the __do_IRQ() super-handler another type |
104 | was identified: | 108 | was identified: |
105 | <itemizedlist> | 109 | <itemizedlist> |
@@ -153,6 +157,7 @@ | |||
153 | is still available. This leads to a kind of duality for the time | 157 | is still available. This leads to a kind of duality for the time |
154 | being. Over time the new model should be used in more and more | 158 | being. Over time the new model should be used in more and more |
155 | architectures, as it enables smaller and cleaner IRQ subsystems. | 159 | architectures, as it enables smaller and cleaner IRQ subsystems. |
160 | It's deprecated for three years now and about to be removed. | ||
156 | </para> | 161 | </para> |
157 | </chapter> | 162 | </chapter> |
158 | <chapter id="bugs"> | 163 | <chapter id="bugs"> |
@@ -217,6 +222,7 @@ | |||
217 | <itemizedlist> | 222 | <itemizedlist> |
218 | <listitem><para>handle_level_irq</para></listitem> | 223 | <listitem><para>handle_level_irq</para></listitem> |
219 | <listitem><para>handle_edge_irq</para></listitem> | 224 | <listitem><para>handle_edge_irq</para></listitem> |
225 | <listitem><para>handle_fasteoi_irq</para></listitem> | ||
220 | <listitem><para>handle_simple_irq</para></listitem> | 226 | <listitem><para>handle_simple_irq</para></listitem> |
221 | <listitem><para>handle_percpu_irq</para></listitem> | 227 | <listitem><para>handle_percpu_irq</para></listitem> |
222 | </itemizedlist> | 228 | </itemizedlist> |
@@ -233,33 +239,33 @@ | |||
233 | are used by the default flow implementations. | 239 | are used by the default flow implementations. |
234 | The following helper functions are implemented (simplified excerpt): | 240 | The following helper functions are implemented (simplified excerpt): |
235 | <programlisting> | 241 | <programlisting> |
236 | default_enable(irq) | 242 | default_enable(struct irq_data *data) |
237 | { | 243 | { |
238 | desc->chip->unmask(irq); | 244 | desc->chip->irq_unmask(data); |
239 | } | 245 | } |
240 | 246 | ||
241 | default_disable(irq) | 247 | default_disable(struct irq_data *data) |
242 | { | 248 | { |
243 | if (!delay_disable(irq)) | 249 | if (!delay_disable(data)) |
244 | desc->chip->mask(irq); | 250 | desc->chip->irq_mask(data); |
245 | } | 251 | } |
246 | 252 | ||
247 | default_ack(irq) | 253 | default_ack(struct irq_data *data) |
248 | { | 254 | { |
249 | chip->ack(irq); | 255 | chip->irq_ack(data); |
250 | } | 256 | } |
251 | 257 | ||
252 | default_mask_ack(irq) | 258 | default_mask_ack(struct irq_data *data) |
253 | { | 259 | { |
254 | if (chip->mask_ack) { | 260 | if (chip->irq_mask_ack) { |
255 | chip->mask_ack(irq); | 261 | chip->irq_mask_ack(data); |
256 | } else { | 262 | } else { |
257 | chip->mask(irq); | 263 | chip->irq_mask(data); |
258 | chip->ack(irq); | 264 | chip->irq_ack(data); |
259 | } | 265 | } |
260 | } | 266 | } |
261 | 267 | ||
262 | noop(irq) | 268 | noop(struct irq_data *data)) |
263 | { | 269 | { |
264 | } | 270 | } |
265 | 271 | ||
@@ -278,12 +284,27 @@ noop(irq) | |||
278 | <para> | 284 | <para> |
279 | The following control flow is implemented (simplified excerpt): | 285 | The following control flow is implemented (simplified excerpt): |
280 | <programlisting> | 286 | <programlisting> |
281 | desc->chip->start(); | 287 | desc->chip->irq_mask(); |
282 | handle_IRQ_event(desc->action); | 288 | handle_IRQ_event(desc->action); |
283 | desc->chip->end(); | 289 | desc->chip->irq_unmask(); |
284 | </programlisting> | 290 | </programlisting> |
285 | </para> | 291 | </para> |
286 | </sect3> | 292 | </sect3> |
293 | <sect3 id="Default_FASTEOI_IRQ_flow_handler"> | ||
294 | <title>Default Fast EOI IRQ flow handler</title> | ||
295 | <para> | ||
296 | handle_fasteoi_irq provides a generic implementation | ||
297 | for interrupts, which only need an EOI at the end of | ||
298 | the handler | ||
299 | </para> | ||
300 | <para> | ||
301 | The following control flow is implemented (simplified excerpt): | ||
302 | <programlisting> | ||
303 | handle_IRQ_event(desc->action); | ||
304 | desc->chip->irq_eoi(); | ||
305 | </programlisting> | ||
306 | </para> | ||
307 | </sect3> | ||
287 | <sect3 id="Default_Edge_IRQ_flow_handler"> | 308 | <sect3 id="Default_Edge_IRQ_flow_handler"> |
288 | <title>Default Edge IRQ flow handler</title> | 309 | <title>Default Edge IRQ flow handler</title> |
289 | <para> | 310 | <para> |
@@ -294,20 +315,19 @@ desc->chip->end(); | |||
294 | The following control flow is implemented (simplified excerpt): | 315 | The following control flow is implemented (simplified excerpt): |
295 | <programlisting> | 316 | <programlisting> |
296 | if (desc->status & running) { | 317 | if (desc->status & running) { |
297 | desc->chip->hold(); | 318 | desc->chip->irq_mask(); |
298 | desc->status |= pending | masked; | 319 | desc->status |= pending | masked; |
299 | return; | 320 | return; |
300 | } | 321 | } |
301 | desc->chip->start(); | 322 | desc->chip->irq_ack(); |
302 | desc->status |= running; | 323 | desc->status |= running; |
303 | do { | 324 | do { |
304 | if (desc->status & masked) | 325 | if (desc->status & masked) |
305 | desc->chip->enable(); | 326 | desc->chip->irq_unmask(); |
306 | desc->status &= ~pending; | 327 | desc->status &= ~pending; |
307 | handle_IRQ_event(desc->action); | 328 | handle_IRQ_event(desc->action); |
308 | } while (status & pending); | 329 | } while (status & pending); |
309 | desc->status &= ~running; | 330 | desc->status &= ~running; |
310 | desc->chip->end(); | ||
311 | </programlisting> | 331 | </programlisting> |
312 | </para> | 332 | </para> |
313 | </sect3> | 333 | </sect3> |
@@ -342,9 +362,9 @@ handle_IRQ_event(desc->action); | |||
342 | <para> | 362 | <para> |
343 | The following control flow is implemented (simplified excerpt): | 363 | The following control flow is implemented (simplified excerpt): |
344 | <programlisting> | 364 | <programlisting> |
345 | desc->chip->start(); | ||
346 | handle_IRQ_event(desc->action); | 365 | handle_IRQ_event(desc->action); |
347 | desc->chip->end(); | 366 | if (desc->chip->irq_eoi) |
367 | desc->chip->irq_eoi(); | ||
348 | </programlisting> | 368 | </programlisting> |
349 | </para> | 369 | </para> |
350 | </sect3> | 370 | </sect3> |
@@ -375,8 +395,7 @@ desc->chip->end(); | |||
375 | mechanism. (It's necessary to enable CONFIG_HARDIRQS_SW_RESEND when | 395 | mechanism. (It's necessary to enable CONFIG_HARDIRQS_SW_RESEND when |
376 | you want to use the delayed interrupt disable feature and your | 396 | you want to use the delayed interrupt disable feature and your |
377 | hardware is not capable of retriggering an interrupt.) | 397 | hardware is not capable of retriggering an interrupt.) |
378 | The delayed interrupt disable can be runtime enabled, per interrupt, | 398 | The delayed interrupt disable is not configurable. |
379 | by setting the IRQ_DELAYED_DISABLE flag in the irq_desc status field. | ||
380 | </para> | 399 | </para> |
381 | </sect2> | 400 | </sect2> |
382 | </sect1> | 401 | </sect1> |
@@ -387,13 +406,13 @@ desc->chip->end(); | |||
387 | contains all the direct chip relevant functions, which | 406 | contains all the direct chip relevant functions, which |
388 | can be utilized by the irq flow implementations. | 407 | can be utilized by the irq flow implementations. |
389 | <itemizedlist> | 408 | <itemizedlist> |
390 | <listitem><para>ack()</para></listitem> | 409 | <listitem><para>irq_ack()</para></listitem> |
391 | <listitem><para>mask_ack() - Optional, recommended for performance</para></listitem> | 410 | <listitem><para>irq_mask_ack() - Optional, recommended for performance</para></listitem> |
392 | <listitem><para>mask()</para></listitem> | 411 | <listitem><para>irq_mask()</para></listitem> |
393 | <listitem><para>unmask()</para></listitem> | 412 | <listitem><para>irq_unmask()</para></listitem> |
394 | <listitem><para>retrigger() - Optional</para></listitem> | 413 | <listitem><para>irq_retrigger() - Optional</para></listitem> |
395 | <listitem><para>set_type() - Optional</para></listitem> | 414 | <listitem><para>irq_set_type() - Optional</para></listitem> |
396 | <listitem><para>set_wake() - Optional</para></listitem> | 415 | <listitem><para>irq_set_wake() - Optional</para></listitem> |
397 | </itemizedlist> | 416 | </itemizedlist> |
398 | These primitives are strictly intended to mean what they say: ack means | 417 | These primitives are strictly intended to mean what they say: ack means |
399 | ACK, masking means masking of an IRQ line, etc. It is up to the flow | 418 | ACK, masking means masking of an IRQ line, etc. It is up to the flow |
@@ -458,6 +477,7 @@ desc->chip->end(); | |||
458 | <para> | 477 | <para> |
459 | This chapter contains the autogenerated documentation of the internal functions. | 478 | This chapter contains the autogenerated documentation of the internal functions. |
460 | </para> | 479 | </para> |
480 | !Ikernel/irq/irqdesc.c | ||
461 | !Ikernel/irq/handle.c | 481 | !Ikernel/irq/handle.c |
462 | !Ikernel/irq/chip.c | 482 | !Ikernel/irq/chip.c |
463 | </chapter> | 483 | </chapter> |
diff --git a/Documentation/DocBook/kernel-api.tmpl b/Documentation/DocBook/kernel-api.tmpl index 44b3def961a2..6b4e07f28b69 100644 --- a/Documentation/DocBook/kernel-api.tmpl +++ b/Documentation/DocBook/kernel-api.tmpl | |||
@@ -57,7 +57,6 @@ | |||
57 | </para> | 57 | </para> |
58 | 58 | ||
59 | <sect1><title>String Conversions</title> | 59 | <sect1><title>String Conversions</title> |
60 | !Ilib/vsprintf.c | ||
61 | !Elib/vsprintf.c | 60 | !Elib/vsprintf.c |
62 | </sect1> | 61 | </sect1> |
63 | <sect1><title>String Manipulation</title> | 62 | <sect1><title>String Manipulation</title> |
@@ -132,7 +131,6 @@ X!Ilib/string.c | |||
132 | <title>FIFO Buffer</title> | 131 | <title>FIFO Buffer</title> |
133 | <sect1><title>kfifo interface</title> | 132 | <sect1><title>kfifo interface</title> |
134 | !Iinclude/linux/kfifo.h | 133 | !Iinclude/linux/kfifo.h |
135 | !Ekernel/kfifo.c | ||
136 | </sect1> | 134 | </sect1> |
137 | </chapter> | 135 | </chapter> |
138 | 136 | ||
@@ -259,7 +257,8 @@ X!Earch/x86/kernel/mca_32.c | |||
259 | !Iblock/blk-sysfs.c | 257 | !Iblock/blk-sysfs.c |
260 | !Eblock/blk-settings.c | 258 | !Eblock/blk-settings.c |
261 | !Eblock/blk-exec.c | 259 | !Eblock/blk-exec.c |
262 | !Eblock/blk-barrier.c | 260 | !Eblock/blk-flush.c |
261 | !Eblock/blk-lib.c | ||
263 | !Eblock/blk-tag.c | 262 | !Eblock/blk-tag.c |
264 | !Iblock/blk-tag.c | 263 | !Iblock/blk-tag.c |
265 | !Eblock/blk-integrity.c | 264 | !Eblock/blk-integrity.c |
diff --git a/Documentation/DocBook/kernel-locking.tmpl b/Documentation/DocBook/kernel-locking.tmpl index 084f6ad7b7a0..f66f4df18690 100644 --- a/Documentation/DocBook/kernel-locking.tmpl +++ b/Documentation/DocBook/kernel-locking.tmpl | |||
@@ -1645,7 +1645,9 @@ the amount of locking which needs to be done. | |||
1645 | all the readers who were traversing the list when we deleted the | 1645 | all the readers who were traversing the list when we deleted the |
1646 | element are finished. We use <function>call_rcu()</function> to | 1646 | element are finished. We use <function>call_rcu()</function> to |
1647 | register a callback which will actually destroy the object once | 1647 | register a callback which will actually destroy the object once |
1648 | the readers are finished. | 1648 | all pre-existing readers are finished. Alternatively, |
1649 | <function>synchronize_rcu()</function> may be used to block until | ||
1650 | all pre-existing are finished. | ||
1649 | </para> | 1651 | </para> |
1650 | <para> | 1652 | <para> |
1651 | But how does Read Copy Update know when the readers are | 1653 | But how does Read Copy Update know when the readers are |
@@ -1714,7 +1716,7 @@ the amount of locking which needs to be done. | |||
1714 | - object_put(obj); | 1716 | - object_put(obj); |
1715 | + list_del_rcu(&obj->list); | 1717 | + list_del_rcu(&obj->list); |
1716 | cache_num--; | 1718 | cache_num--; |
1717 | + call_rcu(&obj->rcu, cache_delete_rcu, obj); | 1719 | + call_rcu(&obj->rcu, cache_delete_rcu); |
1718 | } | 1720 | } |
1719 | 1721 | ||
1720 | /* Must be holding cache_lock */ | 1722 | /* Must be holding cache_lock */ |
@@ -1725,14 +1727,6 @@ the amount of locking which needs to be done. | |||
1725 | if (++cache_num > MAX_CACHE_SIZE) { | 1727 | if (++cache_num > MAX_CACHE_SIZE) { |
1726 | struct object *i, *outcast = NULL; | 1728 | struct object *i, *outcast = NULL; |
1727 | list_for_each_entry(i, &cache, list) { | 1729 | list_for_each_entry(i, &cache, list) { |
1728 | @@ -85,6 +94,7 @@ | ||
1729 | obj->popularity = 0; | ||
1730 | atomic_set(&obj->refcnt, 1); /* The cache holds a reference */ | ||
1731 | spin_lock_init(&obj->lock); | ||
1732 | + INIT_RCU_HEAD(&obj->rcu); | ||
1733 | |||
1734 | spin_lock_irqsave(&cache_lock, flags); | ||
1735 | __cache_add(obj); | ||
1736 | @@ -104,12 +114,11 @@ | 1730 | @@ -104,12 +114,11 @@ |
1737 | struct object *cache_find(int id) | 1731 | struct object *cache_find(int id) |
1738 | { | 1732 | { |
@@ -1922,9 +1916,12 @@ machines due to caching. | |||
1922 | <function>mutex_lock()</function> | 1916 | <function>mutex_lock()</function> |
1923 | </para> | 1917 | </para> |
1924 | <para> | 1918 | <para> |
1925 | There is a <function>mutex_trylock()</function> which can be | 1919 | There is a <function>mutex_trylock()</function> which does not |
1926 | used inside interrupt context, as it will not sleep. | 1920 | sleep. Still, it must not be used inside interrupt context since |
1921 | its implementation is not safe for that. | ||
1927 | <function>mutex_unlock()</function> will also never sleep. | 1922 | <function>mutex_unlock()</function> will also never sleep. |
1923 | It cannot be used in interrupt context either since a mutex | ||
1924 | must be released by the same task that acquired it. | ||
1928 | </para> | 1925 | </para> |
1929 | </listitem> | 1926 | </listitem> |
1930 | </itemizedlist> | 1927 | </itemizedlist> |
@@ -1958,6 +1955,12 @@ machines due to caching. | |||
1958 | </sect1> | 1955 | </sect1> |
1959 | </chapter> | 1956 | </chapter> |
1960 | 1957 | ||
1958 | <chapter id="apiref"> | ||
1959 | <title>Mutex API reference</title> | ||
1960 | !Iinclude/linux/mutex.h | ||
1961 | !Ekernel/mutex.c | ||
1962 | </chapter> | ||
1963 | |||
1961 | <chapter id="references"> | 1964 | <chapter id="references"> |
1962 | <title>Further reading</title> | 1965 | <title>Further reading</title> |
1963 | 1966 | ||
diff --git a/Documentation/DocBook/mac80211.tmpl b/Documentation/DocBook/mac80211.tmpl deleted file mode 100644 index affb15a344a1..000000000000 --- a/Documentation/DocBook/mac80211.tmpl +++ /dev/null | |||
@@ -1,337 +0,0 @@ | |||
1 | <?xml version="1.0" encoding="UTF-8"?> | ||
2 | <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN" | ||
3 | "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []> | ||
4 | |||
5 | <book id="mac80211-developers-guide"> | ||
6 | <bookinfo> | ||
7 | <title>The mac80211 subsystem for kernel developers</title> | ||
8 | |||
9 | <authorgroup> | ||
10 | <author> | ||
11 | <firstname>Johannes</firstname> | ||
12 | <surname>Berg</surname> | ||
13 | <affiliation> | ||
14 | <address><email>johannes@sipsolutions.net</email></address> | ||
15 | </affiliation> | ||
16 | </author> | ||
17 | </authorgroup> | ||
18 | |||
19 | <copyright> | ||
20 | <year>2007-2009</year> | ||
21 | <holder>Johannes Berg</holder> | ||
22 | </copyright> | ||
23 | |||
24 | <legalnotice> | ||
25 | <para> | ||
26 | This documentation is free software; you can redistribute | ||
27 | it and/or modify it under the terms of the GNU General Public | ||
28 | License version 2 as published by the Free Software Foundation. | ||
29 | </para> | ||
30 | |||
31 | <para> | ||
32 | This documentation is distributed in the hope that it will be | ||
33 | useful, but WITHOUT ANY WARRANTY; without even the implied | ||
34 | warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. | ||
35 | See the GNU General Public License for more details. | ||
36 | </para> | ||
37 | |||
38 | <para> | ||
39 | You should have received a copy of the GNU General Public | ||
40 | License along with this documentation; if not, write to the Free | ||
41 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, | ||
42 | MA 02111-1307 USA | ||
43 | </para> | ||
44 | |||
45 | <para> | ||
46 | For more details see the file COPYING in the source | ||
47 | distribution of Linux. | ||
48 | </para> | ||
49 | </legalnotice> | ||
50 | |||
51 | <abstract> | ||
52 | !Pinclude/net/mac80211.h Introduction | ||
53 | !Pinclude/net/mac80211.h Warning | ||
54 | </abstract> | ||
55 | </bookinfo> | ||
56 | |||
57 | <toc></toc> | ||
58 | |||
59 | <!-- | ||
60 | Generally, this document shall be ordered by increasing complexity. | ||
61 | It is important to note that readers should be able to read only | ||
62 | the first few sections to get a working driver and only advanced | ||
63 | usage should require reading the full document. | ||
64 | --> | ||
65 | |||
66 | <part> | ||
67 | <title>The basic mac80211 driver interface</title> | ||
68 | <partintro> | ||
69 | <para> | ||
70 | You should read and understand the information contained | ||
71 | within this part of the book while implementing a driver. | ||
72 | In some chapters, advanced usage is noted, that may be | ||
73 | skipped at first. | ||
74 | </para> | ||
75 | <para> | ||
76 | This part of the book only covers station and monitor mode | ||
77 | functionality, additional information required to implement | ||
78 | the other modes is covered in the second part of the book. | ||
79 | </para> | ||
80 | </partintro> | ||
81 | |||
82 | <chapter id="basics"> | ||
83 | <title>Basic hardware handling</title> | ||
84 | <para>TBD</para> | ||
85 | <para> | ||
86 | This chapter shall contain information on getting a hw | ||
87 | struct allocated and registered with mac80211. | ||
88 | </para> | ||
89 | <para> | ||
90 | Since it is required to allocate rates/modes before registering | ||
91 | a hw struct, this chapter shall also contain information on setting | ||
92 | up the rate/mode structs. | ||
93 | </para> | ||
94 | <para> | ||
95 | Additionally, some discussion about the callbacks and | ||
96 | the general programming model should be in here, including | ||
97 | the definition of ieee80211_ops which will be referred to | ||
98 | a lot. | ||
99 | </para> | ||
100 | <para> | ||
101 | Finally, a discussion of hardware capabilities should be done | ||
102 | with references to other parts of the book. | ||
103 | </para> | ||
104 | <!-- intentionally multiple !F lines to get proper order --> | ||
105 | !Finclude/net/mac80211.h ieee80211_hw | ||
106 | !Finclude/net/mac80211.h ieee80211_hw_flags | ||
107 | !Finclude/net/mac80211.h SET_IEEE80211_DEV | ||
108 | !Finclude/net/mac80211.h SET_IEEE80211_PERM_ADDR | ||
109 | !Finclude/net/mac80211.h ieee80211_ops | ||
110 | !Finclude/net/mac80211.h ieee80211_alloc_hw | ||
111 | !Finclude/net/mac80211.h ieee80211_register_hw | ||
112 | !Finclude/net/mac80211.h ieee80211_get_tx_led_name | ||
113 | !Finclude/net/mac80211.h ieee80211_get_rx_led_name | ||
114 | !Finclude/net/mac80211.h ieee80211_get_assoc_led_name | ||
115 | !Finclude/net/mac80211.h ieee80211_get_radio_led_name | ||
116 | !Finclude/net/mac80211.h ieee80211_unregister_hw | ||
117 | !Finclude/net/mac80211.h ieee80211_free_hw | ||
118 | </chapter> | ||
119 | |||
120 | <chapter id="phy-handling"> | ||
121 | <title>PHY configuration</title> | ||
122 | <para>TBD</para> | ||
123 | <para> | ||
124 | This chapter should describe PHY handling including | ||
125 | start/stop callbacks and the various structures used. | ||
126 | </para> | ||
127 | !Finclude/net/mac80211.h ieee80211_conf | ||
128 | !Finclude/net/mac80211.h ieee80211_conf_flags | ||
129 | </chapter> | ||
130 | |||
131 | <chapter id="iface-handling"> | ||
132 | <title>Virtual interfaces</title> | ||
133 | <para>TBD</para> | ||
134 | <para> | ||
135 | This chapter should describe virtual interface basics | ||
136 | that are relevant to the driver (VLANs, MGMT etc are not.) | ||
137 | It should explain the use of the add_iface/remove_iface | ||
138 | callbacks as well as the interface configuration callbacks. | ||
139 | </para> | ||
140 | <para>Things related to AP mode should be discussed there.</para> | ||
141 | <para> | ||
142 | Things related to supporting multiple interfaces should be | ||
143 | in the appropriate chapter, a BIG FAT note should be here about | ||
144 | this though and the recommendation to allow only a single | ||
145 | interface in STA mode at first! | ||
146 | </para> | ||
147 | !Finclude/net/mac80211.h ieee80211_vif | ||
148 | </chapter> | ||
149 | |||
150 | <chapter id="rx-tx"> | ||
151 | <title>Receive and transmit processing</title> | ||
152 | <sect1> | ||
153 | <title>what should be here</title> | ||
154 | <para>TBD</para> | ||
155 | <para> | ||
156 | This should describe the receive and transmit | ||
157 | paths in mac80211/the drivers as well as | ||
158 | transmit status handling. | ||
159 | </para> | ||
160 | </sect1> | ||
161 | <sect1> | ||
162 | <title>Frame format</title> | ||
163 | !Pinclude/net/mac80211.h Frame format | ||
164 | </sect1> | ||
165 | <sect1> | ||
166 | <title>Packet alignment</title> | ||
167 | !Pnet/mac80211/rx.c Packet alignment | ||
168 | </sect1> | ||
169 | <sect1> | ||
170 | <title>Calling into mac80211 from interrupts</title> | ||
171 | !Pinclude/net/mac80211.h Calling mac80211 from interrupts | ||
172 | </sect1> | ||
173 | <sect1> | ||
174 | <title>functions/definitions</title> | ||
175 | !Finclude/net/mac80211.h ieee80211_rx_status | ||
176 | !Finclude/net/mac80211.h mac80211_rx_flags | ||
177 | !Finclude/net/mac80211.h ieee80211_tx_info | ||
178 | !Finclude/net/mac80211.h ieee80211_rx | ||
179 | !Finclude/net/mac80211.h ieee80211_rx_irqsafe | ||
180 | !Finclude/net/mac80211.h ieee80211_tx_status | ||
181 | !Finclude/net/mac80211.h ieee80211_tx_status_irqsafe | ||
182 | !Finclude/net/mac80211.h ieee80211_rts_get | ||
183 | !Finclude/net/mac80211.h ieee80211_rts_duration | ||
184 | !Finclude/net/mac80211.h ieee80211_ctstoself_get | ||
185 | !Finclude/net/mac80211.h ieee80211_ctstoself_duration | ||
186 | !Finclude/net/mac80211.h ieee80211_generic_frame_duration | ||
187 | !Finclude/net/mac80211.h ieee80211_wake_queue | ||
188 | !Finclude/net/mac80211.h ieee80211_stop_queue | ||
189 | !Finclude/net/mac80211.h ieee80211_wake_queues | ||
190 | !Finclude/net/mac80211.h ieee80211_stop_queues | ||
191 | </sect1> | ||
192 | </chapter> | ||
193 | |||
194 | <chapter id="filters"> | ||
195 | <title>Frame filtering</title> | ||
196 | !Pinclude/net/mac80211.h Frame filtering | ||
197 | !Finclude/net/mac80211.h ieee80211_filter_flags | ||
198 | </chapter> | ||
199 | </part> | ||
200 | |||
201 | <part id="advanced"> | ||
202 | <title>Advanced driver interface</title> | ||
203 | <partintro> | ||
204 | <para> | ||
205 | Information contained within this part of the book is | ||
206 | of interest only for advanced interaction of mac80211 | ||
207 | with drivers to exploit more hardware capabilities and | ||
208 | improve performance. | ||
209 | </para> | ||
210 | </partintro> | ||
211 | |||
212 | <chapter id="hardware-crypto-offload"> | ||
213 | <title>Hardware crypto acceleration</title> | ||
214 | !Pinclude/net/mac80211.h Hardware crypto acceleration | ||
215 | <!-- intentionally multiple !F lines to get proper order --> | ||
216 | !Finclude/net/mac80211.h set_key_cmd | ||
217 | !Finclude/net/mac80211.h ieee80211_key_conf | ||
218 | !Finclude/net/mac80211.h ieee80211_key_alg | ||
219 | !Finclude/net/mac80211.h ieee80211_key_flags | ||
220 | </chapter> | ||
221 | |||
222 | <chapter id="powersave"> | ||
223 | <title>Powersave support</title> | ||
224 | !Pinclude/net/mac80211.h Powersave support | ||
225 | </chapter> | ||
226 | |||
227 | <chapter id="beacon-filter"> | ||
228 | <title>Beacon filter support</title> | ||
229 | !Pinclude/net/mac80211.h Beacon filter support | ||
230 | !Finclude/net/mac80211.h ieee80211_beacon_loss | ||
231 | </chapter> | ||
232 | |||
233 | <chapter id="qos"> | ||
234 | <title>Multiple queues and QoS support</title> | ||
235 | <para>TBD</para> | ||
236 | !Finclude/net/mac80211.h ieee80211_tx_queue_params | ||
237 | </chapter> | ||
238 | |||
239 | <chapter id="AP"> | ||
240 | <title>Access point mode support</title> | ||
241 | <para>TBD</para> | ||
242 | <para>Some parts of the if_conf should be discussed here instead</para> | ||
243 | <para> | ||
244 | Insert notes about VLAN interfaces with hw crypto here or | ||
245 | in the hw crypto chapter. | ||
246 | </para> | ||
247 | !Finclude/net/mac80211.h ieee80211_get_buffered_bc | ||
248 | !Finclude/net/mac80211.h ieee80211_beacon_get | ||
249 | </chapter> | ||
250 | |||
251 | <chapter id="multi-iface"> | ||
252 | <title>Supporting multiple virtual interfaces</title> | ||
253 | <para>TBD</para> | ||
254 | <para> | ||
255 | Note: WDS with identical MAC address should almost always be OK | ||
256 | </para> | ||
257 | <para> | ||
258 | Insert notes about having multiple virtual interfaces with | ||
259 | different MAC addresses here, note which configurations are | ||
260 | supported by mac80211, add notes about supporting hw crypto | ||
261 | with it. | ||
262 | </para> | ||
263 | </chapter> | ||
264 | |||
265 | <chapter id="hardware-scan-offload"> | ||
266 | <title>Hardware scan offload</title> | ||
267 | <para>TBD</para> | ||
268 | !Finclude/net/mac80211.h ieee80211_scan_completed | ||
269 | </chapter> | ||
270 | </part> | ||
271 | |||
272 | <part id="rate-control"> | ||
273 | <title>Rate control interface</title> | ||
274 | <partintro> | ||
275 | <para>TBD</para> | ||
276 | <para> | ||
277 | This part of the book describes the rate control algorithm | ||
278 | interface and how it relates to mac80211 and drivers. | ||
279 | </para> | ||
280 | </partintro> | ||
281 | <chapter id="dummy"> | ||
282 | <title>dummy chapter</title> | ||
283 | <para>TBD</para> | ||
284 | </chapter> | ||
285 | </part> | ||
286 | |||
287 | <part id="internal"> | ||
288 | <title>Internals</title> | ||
289 | <partintro> | ||
290 | <para>TBD</para> | ||
291 | <para> | ||
292 | This part of the book describes mac80211 internals. | ||
293 | </para> | ||
294 | </partintro> | ||
295 | |||
296 | <chapter id="key-handling"> | ||
297 | <title>Key handling</title> | ||
298 | <sect1> | ||
299 | <title>Key handling basics</title> | ||
300 | !Pnet/mac80211/key.c Key handling basics | ||
301 | </sect1> | ||
302 | <sect1> | ||
303 | <title>MORE TBD</title> | ||
304 | <para>TBD</para> | ||
305 | </sect1> | ||
306 | </chapter> | ||
307 | |||
308 | <chapter id="rx-processing"> | ||
309 | <title>Receive processing</title> | ||
310 | <para>TBD</para> | ||
311 | </chapter> | ||
312 | |||
313 | <chapter id="tx-processing"> | ||
314 | <title>Transmit processing</title> | ||
315 | <para>TBD</para> | ||
316 | </chapter> | ||
317 | |||
318 | <chapter id="sta-info"> | ||
319 | <title>Station info handling</title> | ||
320 | <sect1> | ||
321 | <title>Programming information</title> | ||
322 | !Fnet/mac80211/sta_info.h sta_info | ||
323 | !Fnet/mac80211/sta_info.h ieee80211_sta_info_flags | ||
324 | </sect1> | ||
325 | <sect1> | ||
326 | <title>STA information lifetime rules</title> | ||
327 | !Pnet/mac80211/sta_info.c STA information lifetime rules | ||
328 | </sect1> | ||
329 | </chapter> | ||
330 | |||
331 | <chapter id="synchronisation"> | ||
332 | <title>Synchronisation</title> | ||
333 | <para>TBD</para> | ||
334 | <para>Locking, lots of RCU</para> | ||
335 | </chapter> | ||
336 | </part> | ||
337 | </book> | ||
diff --git a/Documentation/DocBook/tracepoint.tmpl b/Documentation/DocBook/tracepoint.tmpl index e8473eae2a20..b57a9ede3224 100644 --- a/Documentation/DocBook/tracepoint.tmpl +++ b/Documentation/DocBook/tracepoint.tmpl | |||
@@ -104,4 +104,9 @@ | |||
104 | <title>Block IO</title> | 104 | <title>Block IO</title> |
105 | !Iinclude/trace/events/block.h | 105 | !Iinclude/trace/events/block.h |
106 | </chapter> | 106 | </chapter> |
107 | |||
108 | <chapter id="workqueue"> | ||
109 | <title>Workqueue</title> | ||
110 | !Iinclude/trace/events/workqueue.h | ||
111 | </chapter> | ||
107 | </book> | 112 | </book> |
diff --git a/Documentation/RCU/checklist.txt b/Documentation/RCU/checklist.txt index 790d1a812376..0c134f8afc6f 100644 --- a/Documentation/RCU/checklist.txt +++ b/Documentation/RCU/checklist.txt | |||
@@ -218,13 +218,22 @@ over a rather long period of time, but improvements are always welcome! | |||
218 | include: | 218 | include: |
219 | 219 | ||
220 | a. Keeping a count of the number of data-structure elements | 220 | a. Keeping a count of the number of data-structure elements |
221 | used by the RCU-protected data structure, including those | 221 | used by the RCU-protected data structure, including |
222 | waiting for a grace period to elapse. Enforce a limit | 222 | those waiting for a grace period to elapse. Enforce a |
223 | on this number, stalling updates as needed to allow | 223 | limit on this number, stalling updates as needed to allow |
224 | previously deferred frees to complete. | 224 | previously deferred frees to complete. Alternatively, |
225 | 225 | limit only the number awaiting deferred free rather than | |
226 | Alternatively, limit only the number awaiting deferred | 226 | the total number of elements. |
227 | free rather than the total number of elements. | 227 | |
228 | One way to stall the updates is to acquire the update-side | ||
229 | mutex. (Don't try this with a spinlock -- other CPUs | ||
230 | spinning on the lock could prevent the grace period | ||
231 | from ever ending.) Another way to stall the updates | ||
232 | is for the updates to use a wrapper function around | ||
233 | the memory allocator, so that this wrapper function | ||
234 | simulates OOM when there is too much memory awaiting an | ||
235 | RCU grace period. There are of course many other | ||
236 | variations on this theme. | ||
228 | 237 | ||
229 | b. Limiting update rate. For example, if updates occur only | 238 | b. Limiting update rate. For example, if updates occur only |
230 | once per hour, then no explicit rate limiting is required, | 239 | once per hour, then no explicit rate limiting is required, |
@@ -365,3 +374,26 @@ over a rather long period of time, but improvements are always welcome! | |||
365 | and the compiler to freely reorder code into and out of RCU | 374 | and the compiler to freely reorder code into and out of RCU |
366 | read-side critical sections. It is the responsibility of the | 375 | read-side critical sections. It is the responsibility of the |
367 | RCU update-side primitives to deal with this. | 376 | RCU update-side primitives to deal with this. |
377 | |||
378 | 17. Use CONFIG_PROVE_RCU, CONFIG_DEBUG_OBJECTS_RCU_HEAD, and | ||
379 | the __rcu sparse checks to validate your RCU code. These | ||
380 | can help find problems as follows: | ||
381 | |||
382 | CONFIG_PROVE_RCU: check that accesses to RCU-protected data | ||
383 | structures are carried out under the proper RCU | ||
384 | read-side critical section, while holding the right | ||
385 | combination of locks, or whatever other conditions | ||
386 | are appropriate. | ||
387 | |||
388 | CONFIG_DEBUG_OBJECTS_RCU_HEAD: check that you don't pass the | ||
389 | same object to call_rcu() (or friends) before an RCU | ||
390 | grace period has elapsed since the last time that you | ||
391 | passed that same object to call_rcu() (or friends). | ||
392 | |||
393 | __rcu sparse checks: tag the pointer to the RCU-protected data | ||
394 | structure with __rcu, and sparse will warn you if you | ||
395 | access that pointer without the services of one of the | ||
396 | variants of rcu_dereference(). | ||
397 | |||
398 | These debugging aids can help you find problems that are | ||
399 | otherwise extremely difficult to spot. | ||
diff --git a/Documentation/RCU/stallwarn.txt b/Documentation/RCU/stallwarn.txt index 44c6dcc93d6d..862c08ef1fde 100644 --- a/Documentation/RCU/stallwarn.txt +++ b/Documentation/RCU/stallwarn.txt | |||
@@ -80,6 +80,24 @@ o A CPU looping with bottom halves disabled. This condition can | |||
80 | o For !CONFIG_PREEMPT kernels, a CPU looping anywhere in the kernel | 80 | o For !CONFIG_PREEMPT kernels, a CPU looping anywhere in the kernel |
81 | without invoking schedule(). | 81 | without invoking schedule(). |
82 | 82 | ||
83 | o A CPU-bound real-time task in a CONFIG_PREEMPT kernel, which might | ||
84 | happen to preempt a low-priority task in the middle of an RCU | ||
85 | read-side critical section. This is especially damaging if | ||
86 | that low-priority task is not permitted to run on any other CPU, | ||
87 | in which case the next RCU grace period can never complete, which | ||
88 | will eventually cause the system to run out of memory and hang. | ||
89 | While the system is in the process of running itself out of | ||
90 | memory, you might see stall-warning messages. | ||
91 | |||
92 | o A CPU-bound real-time task in a CONFIG_PREEMPT_RT kernel that | ||
93 | is running at a higher priority than the RCU softirq threads. | ||
94 | This will prevent RCU callbacks from ever being invoked, | ||
95 | and in a CONFIG_TREE_PREEMPT_RCU kernel will further prevent | ||
96 | RCU grace periods from ever completing. Either way, the | ||
97 | system will eventually run out of memory and hang. In the | ||
98 | CONFIG_TREE_PREEMPT_RCU case, you might see stall-warning | ||
99 | messages. | ||
100 | |||
83 | o A bug in the RCU implementation. | 101 | o A bug in the RCU implementation. |
84 | 102 | ||
85 | o A hardware failure. This is quite unlikely, but has occurred | 103 | o A hardware failure. This is quite unlikely, but has occurred |
diff --git a/Documentation/RCU/trace.txt b/Documentation/RCU/trace.txt index efd8cc95c06b..a851118775d8 100644 --- a/Documentation/RCU/trace.txt +++ b/Documentation/RCU/trace.txt | |||
@@ -125,6 +125,17 @@ o "b" is the batch limit for this CPU. If more than this number | |||
125 | of RCU callbacks is ready to invoke, then the remainder will | 125 | of RCU callbacks is ready to invoke, then the remainder will |
126 | be deferred. | 126 | be deferred. |
127 | 127 | ||
128 | o "ci" is the number of RCU callbacks that have been invoked for | ||
129 | this CPU. Note that ci+ql is the number of callbacks that have | ||
130 | been registered in absence of CPU-hotplug activity. | ||
131 | |||
132 | o "co" is the number of RCU callbacks that have been orphaned due to | ||
133 | this CPU going offline. | ||
134 | |||
135 | o "ca" is the number of RCU callbacks that have been adopted due to | ||
136 | other CPUs going offline. Note that ci+co-ca+ql is the number of | ||
137 | RCU callbacks registered on this CPU. | ||
138 | |||
128 | There is also an rcu/rcudata.csv file with the same information in | 139 | There is also an rcu/rcudata.csv file with the same information in |
129 | comma-separated-variable spreadsheet format. | 140 | comma-separated-variable spreadsheet format. |
130 | 141 | ||
@@ -180,7 +191,7 @@ o "s" is the "signaled" state that drives force_quiescent_state()'s | |||
180 | 191 | ||
181 | o "jfq" is the number of jiffies remaining for this grace period | 192 | o "jfq" is the number of jiffies remaining for this grace period |
182 | before force_quiescent_state() is invoked to help push things | 193 | before force_quiescent_state() is invoked to help push things |
183 | along. Note that CPUs in dyntick-idle mode thoughout the grace | 194 | along. Note that CPUs in dyntick-idle mode throughout the grace |
184 | period will not report on their own, but rather must be check by | 195 | period will not report on their own, but rather must be check by |
185 | some other CPU via force_quiescent_state(). | 196 | some other CPU via force_quiescent_state(). |
186 | 197 | ||
diff --git a/Documentation/acpi/method-customizing.txt b/Documentation/acpi/method-customizing.txt index e628cd23ca80..3e1d25aee3fb 100644 --- a/Documentation/acpi/method-customizing.txt +++ b/Documentation/acpi/method-customizing.txt | |||
@@ -19,6 +19,8 @@ Note: Only ACPI METHOD can be overridden, any other object types like | |||
19 | "Device", "OperationRegion", are not recognized. | 19 | "Device", "OperationRegion", are not recognized. |
20 | Note: The same ACPI control method can be overridden for many times, | 20 | Note: The same ACPI control method can be overridden for many times, |
21 | and it's always the latest one that used by Linux/kernel. | 21 | and it's always the latest one that used by Linux/kernel. |
22 | Note: To get the ACPI debug object output (Store (AAAA, Debug)), | ||
23 | please run "echo 1 > /sys/module/acpi/parameters/aml_debug_output". | ||
22 | 24 | ||
23 | 1. override an existing method | 25 | 1. override an existing method |
24 | a) get the ACPI table via ACPI sysfs I/F. e.g. to get the DSDT, | 26 | a) get the ACPI table via ACPI sysfs I/F. e.g. to get the DSDT, |
diff --git a/Documentation/arm/00-INDEX b/Documentation/arm/00-INDEX index 7f5fc3ba9c91..ecf7d04bca26 100644 --- a/Documentation/arm/00-INDEX +++ b/Documentation/arm/00-INDEX | |||
@@ -6,6 +6,8 @@ Interrupts | |||
6 | - ARM Interrupt subsystem documentation | 6 | - ARM Interrupt subsystem documentation |
7 | IXP2000 | 7 | IXP2000 |
8 | - Release Notes for Linux on Intel's IXP2000 Network Processor | 8 | - Release Notes for Linux on Intel's IXP2000 Network Processor |
9 | msm | ||
10 | - MSM specific documentation | ||
9 | Netwinder | 11 | Netwinder |
10 | - Netwinder specific documentation | 12 | - Netwinder specific documentation |
11 | Porting | 13 | Porting |
diff --git a/Documentation/arm/msm/gpiomux.txt b/Documentation/arm/msm/gpiomux.txt new file mode 100644 index 000000000000..67a81620adf6 --- /dev/null +++ b/Documentation/arm/msm/gpiomux.txt | |||
@@ -0,0 +1,176 @@ | |||
1 | This document provides an overview of the msm_gpiomux interface, which | ||
2 | is used to provide gpio pin multiplexing and configuration on mach-msm | ||
3 | targets. | ||
4 | |||
5 | History | ||
6 | ======= | ||
7 | |||
8 | The first-generation API for gpio configuration & multiplexing on msm | ||
9 | is the function gpio_tlmm_config(). This function has a few notable | ||
10 | shortcomings, which led to its deprecation and replacement by gpiomux: | ||
11 | |||
12 | The 'disable' parameter: Setting the second parameter to | ||
13 | gpio_tlmm_config to GPIO_CFG_DISABLE tells the peripheral | ||
14 | processor in charge of the subsystem to perform a look-up into a | ||
15 | low-power table and apply the low-power/sleep setting for the pin. | ||
16 | As the msm family evolved this became problematic. Not all pins | ||
17 | have sleep settings, not all peripheral processors will accept requests | ||
18 | to apply said sleep settings, and not all msm targets have their gpio | ||
19 | subsystems managed by a peripheral processor. In order to get consistent | ||
20 | behavior on all targets, drivers are forced to ignore this parameter, | ||
21 | rendering it useless. | ||
22 | |||
23 | The 'direction' flag: for all mux-settings other than raw-gpio (0), | ||
24 | the output-enable bit of a gpio is hard-wired to a known | ||
25 | input (usually VDD or ground). For those settings, the direction flag | ||
26 | is meaningless at best, and deceptive at worst. In addition, using the | ||
27 | direction flag to change output-enable (OE) directly can cause trouble in | ||
28 | gpiolib, which has no visibility into gpio direction changes made | ||
29 | in this way. Direction control in gpio mode should be made through gpiolib. | ||
30 | |||
31 | Key Features of gpiomux | ||
32 | ======================= | ||
33 | |||
34 | - A consistent interface across all generations of msm. Drivers can expect | ||
35 | the same results on every target. | ||
36 | - gpiomux plays nicely with gpiolib. Functions that should belong to gpiolib | ||
37 | are left to gpiolib and not duplicated here. gpiomux is written with the | ||
38 | intent that gpio_chips will call gpiomux reference-counting methods | ||
39 | from their request() and free() hooks, providing full integration. | ||
40 | - Tabular configuration. Instead of having to call gpio_tlmm_config | ||
41 | hundreds of times, gpio configuration is placed in a single table. | ||
42 | - Per-gpio sleep. Each gpio is individually reference counted, allowing only | ||
43 | those lines which are in use to be put in high-power states. | ||
44 | - 0 means 'do nothing': all flags are designed so that the default memset-zero | ||
45 | equates to a sensible default of 'no configuration', preventing users | ||
46 | from having to provide hundreds of 'no-op' configs for unused or | ||
47 | unwanted lines. | ||
48 | |||
49 | Usage | ||
50 | ===== | ||
51 | |||
52 | To use gpiomux, provide configuration information for relevant gpio lines | ||
53 | in the msm_gpiomux_configs table. Since a 0 equates to "unconfigured", | ||
54 | only those lines to be managed by gpiomux need to be specified. Here | ||
55 | is a completely fictional example: | ||
56 | |||
57 | struct msm_gpiomux_config msm_gpiomux_configs[GPIOMUX_NGPIOS] = { | ||
58 | [12] = { | ||
59 | .active = GPIOMUX_VALID | GPIOMUX_DRV_8MA | GPIOMUX_FUNC_1, | ||
60 | .suspended = GPIOMUX_VALID | GPIOMUX_PULL_DOWN, | ||
61 | }, | ||
62 | [34] = { | ||
63 | .suspended = GPIOMUX_VALID | GPIOMUX_PULL_DOWN, | ||
64 | }, | ||
65 | }; | ||
66 | |||
67 | To indicate that a gpio is in use, call msm_gpiomux_get() to increase | ||
68 | its reference count. To decrease the reference count, call msm_gpiomux_put(). | ||
69 | |||
70 | The effect of this configuration is as follows: | ||
71 | |||
72 | When the system boots, gpios 12 and 34 will be initialized with their | ||
73 | 'suspended' configurations. All other gpios, which were left unconfigured, | ||
74 | will not be touched. | ||
75 | |||
76 | When msm_gpiomux_get() is called on gpio 12 to raise its reference count | ||
77 | above 0, its active configuration will be applied. Since no other gpio | ||
78 | line has a valid active configuration, msm_gpiomux_get() will have no | ||
79 | effect on any other line. | ||
80 | |||
81 | When msm_gpiomux_put() is called on gpio 12 or 34 to drop their reference | ||
82 | count to 0, their suspended configurations will be applied. | ||
83 | Since no other gpio line has a valid suspended configuration, no other | ||
84 | gpio line will be effected by msm_gpiomux_put(). Since gpio 34 has no valid | ||
85 | active configuration, this is effectively a no-op for gpio 34 as well, | ||
86 | with one small caveat, see the section "About Output-Enable Settings". | ||
87 | |||
88 | All of the GPIOMUX_VALID flags may seem like unnecessary overhead, but | ||
89 | they address some important issues. As unused entries (all those | ||
90 | except 12 and 34) are zero-filled, gpiomux needs a way to distinguish | ||
91 | the used fields from the unused. In addition, the all-zero pattern | ||
92 | is a valid configuration! Therefore, gpiomux defines an additional bit | ||
93 | which is used to indicate when a field is used. This has the pleasant | ||
94 | side-effect of allowing calls to msm_gpiomux_write to use '0' to indicate | ||
95 | that a value should not be changed: | ||
96 | |||
97 | msm_gpiomux_write(0, GPIOMUX_VALID, 0); | ||
98 | |||
99 | replaces the active configuration of gpio 0 with an all-zero configuration, | ||
100 | but leaves the suspended configuration as it was. | ||
101 | |||
102 | Static Configurations | ||
103 | ===================== | ||
104 | |||
105 | To install a static configuration, which is applied at boot and does | ||
106 | not change after that, install a configuration with a suspended component | ||
107 | but no active component, as in the previous example: | ||
108 | |||
109 | [34] = { | ||
110 | .suspended = GPIOMUX_VALID | GPIOMUX_PULL_DOWN, | ||
111 | }, | ||
112 | |||
113 | The suspended setting is applied during boot, and the lack of any valid | ||
114 | active setting prevents any other setting from being applied at runtime. | ||
115 | If other subsystems attempting to access the line is a concern, one could | ||
116 | *really* anchor the configuration down by calling msm_gpiomux_get on the | ||
117 | line at initialization to move the line into active mode. With the line | ||
118 | held, it will never be re-suspended, and with no valid active configuration, | ||
119 | no new configurations will be applied. | ||
120 | |||
121 | But then, if having other subsystems grabbing for the line is truly a concern, | ||
122 | it should be reserved with gpio_request instead, which carries an implicit | ||
123 | msm_gpiomux_get. | ||
124 | |||
125 | gpiomux and gpiolib | ||
126 | =================== | ||
127 | |||
128 | It is expected that msm gpio_chips will call msm_gpiomux_get() and | ||
129 | msm_gpiomux_put() from their request and free hooks, like this fictional | ||
130 | example: | ||
131 | |||
132 | static int request(struct gpio_chip *chip, unsigned offset) | ||
133 | { | ||
134 | return msm_gpiomux_get(chip->base + offset); | ||
135 | } | ||
136 | |||
137 | static void free(struct gpio_chip *chip, unsigned offset) | ||
138 | { | ||
139 | msm_gpiomux_put(chip->base + offset); | ||
140 | } | ||
141 | |||
142 | ...somewhere in a gpio_chip declaration... | ||
143 | .request = request, | ||
144 | .free = free, | ||
145 | |||
146 | This provides important functionality: | ||
147 | - It guarantees that a gpio line will have its 'active' config applied | ||
148 | when the line is requested, and will not be suspended while the line | ||
149 | remains requested; and | ||
150 | - It guarantees that gpio-direction settings from gpiolib behave sensibly. | ||
151 | See "About Output-Enable Settings." | ||
152 | |||
153 | This mechanism allows for "auto-request" of gpiomux lines via gpiolib | ||
154 | when it is suitable. Drivers wishing more exact control are, of course, | ||
155 | free to also use msm_gpiomux_set and msm_gpiomux_get. | ||
156 | |||
157 | About Output-Enable Settings | ||
158 | ============================ | ||
159 | |||
160 | Some msm targets do not have the ability to query the current gpio | ||
161 | configuration setting. This means that changes made to the output-enable | ||
162 | (OE) bit by gpiolib cannot be consistently detected and preserved by gpiomux. | ||
163 | Therefore, when gpiomux applies a configuration setting, any direction | ||
164 | settings which may have been applied by gpiolib are lost and the default | ||
165 | input settings are re-applied. | ||
166 | |||
167 | For this reason, drivers should not assume that gpio direction settings | ||
168 | continue to hold if they free and then re-request a gpio. This seems like | ||
169 | common sense - after all, anybody could have obtained the line in the | ||
170 | meantime - but it needs saying. | ||
171 | |||
172 | This also means that calls to msm_gpiomux_write will reset the OE bit, | ||
173 | which means that if the gpio line is held by a client of gpiolib and | ||
174 | msm_gpiomux_write is called, the direction setting has been lost and | ||
175 | gpiolib's internal state has been broken. | ||
176 | Release gpio lines before reconfiguring them. | ||
diff --git a/Documentation/block/00-INDEX b/Documentation/block/00-INDEX index a406286f6f3e..d111e3b23db0 100644 --- a/Documentation/block/00-INDEX +++ b/Documentation/block/00-INDEX | |||
@@ -1,7 +1,5 @@ | |||
1 | 00-INDEX | 1 | 00-INDEX |
2 | - This file | 2 | - This file |
3 | barrier.txt | ||
4 | - I/O Barriers | ||
5 | biodoc.txt | 3 | biodoc.txt |
6 | - Notes on the Generic Block Layer Rewrite in Linux 2.5 | 4 | - Notes on the Generic Block Layer Rewrite in Linux 2.5 |
7 | capability.txt | 5 | capability.txt |
@@ -16,3 +14,5 @@ stat.txt | |||
16 | - Block layer statistics in /sys/block/<dev>/stat | 14 | - Block layer statistics in /sys/block/<dev>/stat |
17 | switching-sched.txt | 15 | switching-sched.txt |
18 | - Switching I/O schedulers at runtime | 16 | - Switching I/O schedulers at runtime |
17 | writeback_cache_control.txt | ||
18 | - Control of volatile write back caches | ||
diff --git a/Documentation/block/barrier.txt b/Documentation/block/barrier.txt deleted file mode 100644 index 2c2f24f634e4..000000000000 --- a/Documentation/block/barrier.txt +++ /dev/null | |||
@@ -1,261 +0,0 @@ | |||
1 | I/O Barriers | ||
2 | ============ | ||
3 | Tejun Heo <htejun@gmail.com>, July 22 2005 | ||
4 | |||
5 | I/O barrier requests are used to guarantee ordering around the barrier | ||
6 | requests. Unless you're crazy enough to use disk drives for | ||
7 | implementing synchronization constructs (wow, sounds interesting...), | ||
8 | the ordering is meaningful only for write requests for things like | ||
9 | journal checkpoints. All requests queued before a barrier request | ||
10 | must be finished (made it to the physical medium) before the barrier | ||
11 | request is started, and all requests queued after the barrier request | ||
12 | must be started only after the barrier request is finished (again, | ||
13 | made it to the physical medium). | ||
14 | |||
15 | In other words, I/O barrier requests have the following two properties. | ||
16 | |||
17 | 1. Request ordering | ||
18 | |||
19 | Requests cannot pass the barrier request. Preceding requests are | ||
20 | processed before the barrier and following requests after. | ||
21 | |||
22 | Depending on what features a drive supports, this can be done in one | ||
23 | of the following three ways. | ||
24 | |||
25 | i. For devices which have queue depth greater than 1 (TCQ devices) and | ||
26 | support ordered tags, block layer can just issue the barrier as an | ||
27 | ordered request and the lower level driver, controller and drive | ||
28 | itself are responsible for making sure that the ordering constraint is | ||
29 | met. Most modern SCSI controllers/drives should support this. | ||
30 | |||
31 | NOTE: SCSI ordered tag isn't currently used due to limitation in the | ||
32 | SCSI midlayer, see the following random notes section. | ||
33 | |||
34 | ii. For devices which have queue depth greater than 1 but don't | ||
35 | support ordered tags, block layer ensures that the requests preceding | ||
36 | a barrier request finishes before issuing the barrier request. Also, | ||
37 | it defers requests following the barrier until the barrier request is | ||
38 | finished. Older SCSI controllers/drives and SATA drives fall in this | ||
39 | category. | ||
40 | |||
41 | iii. Devices which have queue depth of 1. This is a degenerate case | ||
42 | of ii. Just keeping issue order suffices. Ancient SCSI | ||
43 | controllers/drives and IDE drives are in this category. | ||
44 | |||
45 | 2. Forced flushing to physical medium | ||
46 | |||
47 | Again, if you're not gonna do synchronization with disk drives (dang, | ||
48 | it sounds even more appealing now!), the reason you use I/O barriers | ||
49 | is mainly to protect filesystem integrity when power failure or some | ||
50 | other events abruptly stop the drive from operating and possibly make | ||
51 | the drive lose data in its cache. So, I/O barriers need to guarantee | ||
52 | that requests actually get written to non-volatile medium in order. | ||
53 | |||
54 | There are four cases, | ||
55 | |||
56 | i. No write-back cache. Keeping requests ordered is enough. | ||
57 | |||
58 | ii. Write-back cache but no flush operation. There's no way to | ||
59 | guarantee physical-medium commit order. This kind of devices can't to | ||
60 | I/O barriers. | ||
61 | |||
62 | iii. Write-back cache and flush operation but no FUA (forced unit | ||
63 | access). We need two cache flushes - before and after the barrier | ||
64 | request. | ||
65 | |||
66 | iv. Write-back cache, flush operation and FUA. We still need one | ||
67 | flush to make sure requests preceding a barrier are written to medium, | ||
68 | but post-barrier flush can be avoided by using FUA write on the | ||
69 | barrier itself. | ||
70 | |||
71 | |||
72 | How to support barrier requests in drivers | ||
73 | ------------------------------------------ | ||
74 | |||
75 | All barrier handling is done inside block layer proper. All low level | ||
76 | drivers have to are implementing its prepare_flush_fn and using one | ||
77 | the following two functions to indicate what barrier type it supports | ||
78 | and how to prepare flush requests. Note that the term 'ordered' is | ||
79 | used to indicate the whole sequence of performing barrier requests | ||
80 | including draining and flushing. | ||
81 | |||
82 | typedef void (prepare_flush_fn)(struct request_queue *q, struct request *rq); | ||
83 | |||
84 | int blk_queue_ordered(struct request_queue *q, unsigned ordered, | ||
85 | prepare_flush_fn *prepare_flush_fn); | ||
86 | |||
87 | @q : the queue in question | ||
88 | @ordered : the ordered mode the driver/device supports | ||
89 | @prepare_flush_fn : this function should prepare @rq such that it | ||
90 | flushes cache to physical medium when executed | ||
91 | |||
92 | For example, SCSI disk driver's prepare_flush_fn looks like the | ||
93 | following. | ||
94 | |||
95 | static void sd_prepare_flush(struct request_queue *q, struct request *rq) | ||
96 | { | ||
97 | memset(rq->cmd, 0, sizeof(rq->cmd)); | ||
98 | rq->cmd_type = REQ_TYPE_BLOCK_PC; | ||
99 | rq->timeout = SD_TIMEOUT; | ||
100 | rq->cmd[0] = SYNCHRONIZE_CACHE; | ||
101 | rq->cmd_len = 10; | ||
102 | } | ||
103 | |||
104 | The following seven ordered modes are supported. The following table | ||
105 | shows which mode should be used depending on what features a | ||
106 | device/driver supports. In the leftmost column of table, | ||
107 | QUEUE_ORDERED_ prefix is omitted from the mode names to save space. | ||
108 | |||
109 | The table is followed by description of each mode. Note that in the | ||
110 | descriptions of QUEUE_ORDERED_DRAIN*, '=>' is used whereas '->' is | ||
111 | used for QUEUE_ORDERED_TAG* descriptions. '=>' indicates that the | ||
112 | preceding step must be complete before proceeding to the next step. | ||
113 | '->' indicates that the next step can start as soon as the previous | ||
114 | step is issued. | ||
115 | |||
116 | write-back cache ordered tag flush FUA | ||
117 | ----------------------------------------------------------------------- | ||
118 | NONE yes/no N/A no N/A | ||
119 | DRAIN no no N/A N/A | ||
120 | DRAIN_FLUSH yes no yes no | ||
121 | DRAIN_FUA yes no yes yes | ||
122 | TAG no yes N/A N/A | ||
123 | TAG_FLUSH yes yes yes no | ||
124 | TAG_FUA yes yes yes yes | ||
125 | |||
126 | |||
127 | QUEUE_ORDERED_NONE | ||
128 | I/O barriers are not needed and/or supported. | ||
129 | |||
130 | Sequence: N/A | ||
131 | |||
132 | QUEUE_ORDERED_DRAIN | ||
133 | Requests are ordered by draining the request queue and cache | ||
134 | flushing isn't needed. | ||
135 | |||
136 | Sequence: drain => barrier | ||
137 | |||
138 | QUEUE_ORDERED_DRAIN_FLUSH | ||
139 | Requests are ordered by draining the request queue and both | ||
140 | pre-barrier and post-barrier cache flushings are needed. | ||
141 | |||
142 | Sequence: drain => preflush => barrier => postflush | ||
143 | |||
144 | QUEUE_ORDERED_DRAIN_FUA | ||
145 | Requests are ordered by draining the request queue and | ||
146 | pre-barrier cache flushing is needed. By using FUA on barrier | ||
147 | request, post-barrier flushing can be skipped. | ||
148 | |||
149 | Sequence: drain => preflush => barrier | ||
150 | |||
151 | QUEUE_ORDERED_TAG | ||
152 | Requests are ordered by ordered tag and cache flushing isn't | ||
153 | needed. | ||
154 | |||
155 | Sequence: barrier | ||
156 | |||
157 | QUEUE_ORDERED_TAG_FLUSH | ||
158 | Requests are ordered by ordered tag and both pre-barrier and | ||
159 | post-barrier cache flushings are needed. | ||
160 | |||
161 | Sequence: preflush -> barrier -> postflush | ||
162 | |||
163 | QUEUE_ORDERED_TAG_FUA | ||
164 | Requests are ordered by ordered tag and pre-barrier cache | ||
165 | flushing is needed. By using FUA on barrier request, | ||
166 | post-barrier flushing can be skipped. | ||
167 | |||
168 | Sequence: preflush -> barrier | ||
169 | |||
170 | |||
171 | Random notes/caveats | ||
172 | -------------------- | ||
173 | |||
174 | * SCSI layer currently can't use TAG ordering even if the drive, | ||
175 | controller and driver support it. The problem is that SCSI midlayer | ||
176 | request dispatch function is not atomic. It releases queue lock and | ||
177 | switch to SCSI host lock during issue and it's possible and likely to | ||
178 | happen in time that requests change their relative positions. Once | ||
179 | this problem is solved, TAG ordering can be enabled. | ||
180 | |||
181 | * Currently, no matter which ordered mode is used, there can be only | ||
182 | one barrier request in progress. All I/O barriers are held off by | ||
183 | block layer until the previous I/O barrier is complete. This doesn't | ||
184 | make any difference for DRAIN ordered devices, but, for TAG ordered | ||
185 | devices with very high command latency, passing multiple I/O barriers | ||
186 | to low level *might* be helpful if they are very frequent. Well, this | ||
187 | certainly is a non-issue. I'm writing this just to make clear that no | ||
188 | two I/O barrier is ever passed to low-level driver. | ||
189 | |||
190 | * Completion order. Requests in ordered sequence are issued in order | ||
191 | but not required to finish in order. Barrier implementation can | ||
192 | handle out-of-order completion of ordered sequence. IOW, the requests | ||
193 | MUST be processed in order but the hardware/software completion paths | ||
194 | are allowed to reorder completion notifications - eg. current SCSI | ||
195 | midlayer doesn't preserve completion order during error handling. | ||
196 | |||
197 | * Requeueing order. Low-level drivers are free to requeue any request | ||
198 | after they removed it from the request queue with | ||
199 | blkdev_dequeue_request(). As barrier sequence should be kept in order | ||
200 | when requeued, generic elevator code takes care of putting requests in | ||
201 | order around barrier. See blk_ordered_req_seq() and | ||
202 | ELEVATOR_INSERT_REQUEUE handling in __elv_add_request() for details. | ||
203 | |||
204 | Note that block drivers must not requeue preceding requests while | ||
205 | completing latter requests in an ordered sequence. Currently, no | ||
206 | error checking is done against this. | ||
207 | |||
208 | * Error handling. Currently, block layer will report error to upper | ||
209 | layer if any of requests in an ordered sequence fails. Unfortunately, | ||
210 | this doesn't seem to be enough. Look at the following request flow. | ||
211 | QUEUE_ORDERED_TAG_FLUSH is in use. | ||
212 | |||
213 | [0] [1] [2] [3] [pre] [barrier] [post] < [4] [5] [6] ... > | ||
214 | still in elevator | ||
215 | |||
216 | Let's say request [2], [3] are write requests to update file system | ||
217 | metadata (journal or whatever) and [barrier] is used to mark that | ||
218 | those updates are valid. Consider the following sequence. | ||
219 | |||
220 | i. Requests [0] ~ [post] leaves the request queue and enters | ||
221 | low-level driver. | ||
222 | ii. After a while, unfortunately, something goes wrong and the | ||
223 | drive fails [2]. Note that any of [0], [1] and [3] could have | ||
224 | completed by this time, but [pre] couldn't have been finished | ||
225 | as the drive must process it in order and it failed before | ||
226 | processing that command. | ||
227 | iii. Error handling kicks in and determines that the error is | ||
228 | unrecoverable and fails [2], and resumes operation. | ||
229 | iv. [pre] [barrier] [post] gets processed. | ||
230 | v. *BOOM* power fails | ||
231 | |||
232 | The problem here is that the barrier request is *supposed* to indicate | ||
233 | that filesystem update requests [2] and [3] made it safely to the | ||
234 | physical medium and, if the machine crashes after the barrier is | ||
235 | written, filesystem recovery code can depend on that. Sadly, that | ||
236 | isn't true in this case anymore. IOW, the success of a I/O barrier | ||
237 | should also be dependent on success of some of the preceding requests, | ||
238 | where only upper layer (filesystem) knows what 'some' is. | ||
239 | |||
240 | This can be solved by implementing a way to tell the block layer which | ||
241 | requests affect the success of the following barrier request and | ||
242 | making lower lever drivers to resume operation on error only after | ||
243 | block layer tells it to do so. | ||
244 | |||
245 | As the probability of this happening is very low and the drive should | ||
246 | be faulty, implementing the fix is probably an overkill. But, still, | ||
247 | it's there. | ||
248 | |||
249 | * In previous drafts of barrier implementation, there was fallback | ||
250 | mechanism such that, if FUA or ordered TAG fails, less fancy ordered | ||
251 | mode can be selected and the failed barrier request is retried | ||
252 | automatically. The rationale for this feature was that as FUA is | ||
253 | pretty new in ATA world and ordered tag was never used widely, there | ||
254 | could be devices which report to support those features but choke when | ||
255 | actually given such requests. | ||
256 | |||
257 | This was removed for two reasons 1. it's an overkill 2. it's | ||
258 | impossible to implement properly when TAG ordering is used as low | ||
259 | level drivers resume after an error automatically. If it's ever | ||
260 | needed adding it back and modifying low level drivers accordingly | ||
261 | shouldn't be difficult. | ||
diff --git a/Documentation/block/cfq-iosched.txt b/Documentation/block/cfq-iosched.txt new file mode 100644 index 000000000000..e578feed6d81 --- /dev/null +++ b/Documentation/block/cfq-iosched.txt | |||
@@ -0,0 +1,45 @@ | |||
1 | CFQ ioscheduler tunables | ||
2 | ======================== | ||
3 | |||
4 | slice_idle | ||
5 | ---------- | ||
6 | This specifies how long CFQ should idle for next request on certain cfq queues | ||
7 | (for sequential workloads) and service trees (for random workloads) before | ||
8 | queue is expired and CFQ selects next queue to dispatch from. | ||
9 | |||
10 | By default slice_idle is a non-zero value. That means by default we idle on | ||
11 | queues/service trees. This can be very helpful on highly seeky media like | ||
12 | single spindle SATA/SAS disks where we can cut down on overall number of | ||
13 | seeks and see improved throughput. | ||
14 | |||
15 | Setting slice_idle to 0 will remove all the idling on queues/service tree | ||
16 | level and one should see an overall improved throughput on faster storage | ||
17 | devices like multiple SATA/SAS disks in hardware RAID configuration. The down | ||
18 | side is that isolation provided from WRITES also goes down and notion of | ||
19 | IO priority becomes weaker. | ||
20 | |||
21 | So depending on storage and workload, it might be useful to set slice_idle=0. | ||
22 | In general I think for SATA/SAS disks and software RAID of SATA/SAS disks | ||
23 | keeping slice_idle enabled should be useful. For any configurations where | ||
24 | there are multiple spindles behind single LUN (Host based hardware RAID | ||
25 | controller or for storage arrays), setting slice_idle=0 might end up in better | ||
26 | throughput and acceptable latencies. | ||
27 | |||
28 | CFQ IOPS Mode for group scheduling | ||
29 | =================================== | ||
30 | Basic CFQ design is to provide priority based time slices. Higher priority | ||
31 | process gets bigger time slice and lower priority process gets smaller time | ||
32 | slice. Measuring time becomes harder if storage is fast and supports NCQ and | ||
33 | it would be better to dispatch multiple requests from multiple cfq queues in | ||
34 | request queue at a time. In such scenario, it is not possible to measure time | ||
35 | consumed by single queue accurately. | ||
36 | |||
37 | What is possible though is to measure number of requests dispatched from a | ||
38 | single queue and also allow dispatch from multiple cfq queue at the same time. | ||
39 | This effectively becomes the fairness in terms of IOPS (IO operations per | ||
40 | second). | ||
41 | |||
42 | If one sets slice_idle=0 and if storage supports NCQ, CFQ internally switches | ||
43 | to IOPS mode and starts providing fairness in terms of number of requests | ||
44 | dispatched. Note that this mode switching takes effect only for group | ||
45 | scheduling. For non-cgroup users nothing should change. | ||
diff --git a/Documentation/block/writeback_cache_control.txt b/Documentation/block/writeback_cache_control.txt new file mode 100644 index 000000000000..83407d36630a --- /dev/null +++ b/Documentation/block/writeback_cache_control.txt | |||
@@ -0,0 +1,86 @@ | |||
1 | |||
2 | Explicit volatile write back cache control | ||
3 | ===================================== | ||
4 | |||
5 | Introduction | ||
6 | ------------ | ||
7 | |||
8 | Many storage devices, especially in the consumer market, come with volatile | ||
9 | write back caches. That means the devices signal I/O completion to the | ||
10 | operating system before data actually has hit the non-volatile storage. This | ||
11 | behavior obviously speeds up various workloads, but it means the operating | ||
12 | system needs to force data out to the non-volatile storage when it performs | ||
13 | a data integrity operation like fsync, sync or an unmount. | ||
14 | |||
15 | The Linux block layer provides two simple mechanisms that let filesystems | ||
16 | control the caching behavior of the storage device. These mechanisms are | ||
17 | a forced cache flush, and the Force Unit Access (FUA) flag for requests. | ||
18 | |||
19 | |||
20 | Explicit cache flushes | ||
21 | ---------------------- | ||
22 | |||
23 | The REQ_FLUSH flag can be OR ed into the r/w flags of a bio submitted from | ||
24 | the filesystem and will make sure the volatile cache of the storage device | ||
25 | has been flushed before the actual I/O operation is started. This explicitly | ||
26 | guarantees that previously completed write requests are on non-volatile | ||
27 | storage before the flagged bio starts. In addition the REQ_FLUSH flag can be | ||
28 | set on an otherwise empty bio structure, which causes only an explicit cache | ||
29 | flush without any dependent I/O. It is recommend to use | ||
30 | the blkdev_issue_flush() helper for a pure cache flush. | ||
31 | |||
32 | |||
33 | Forced Unit Access | ||
34 | ----------------- | ||
35 | |||
36 | The REQ_FUA flag can be OR ed into the r/w flags of a bio submitted from the | ||
37 | filesystem and will make sure that I/O completion for this request is only | ||
38 | signaled after the data has been committed to non-volatile storage. | ||
39 | |||
40 | |||
41 | Implementation details for filesystems | ||
42 | -------------------------------------- | ||
43 | |||
44 | Filesystems can simply set the REQ_FLUSH and REQ_FUA bits and do not have to | ||
45 | worry if the underlying devices need any explicit cache flushing and how | ||
46 | the Forced Unit Access is implemented. The REQ_FLUSH and REQ_FUA flags | ||
47 | may both be set on a single bio. | ||
48 | |||
49 | |||
50 | Implementation details for make_request_fn based block drivers | ||
51 | -------------------------------------------------------------- | ||
52 | |||
53 | These drivers will always see the REQ_FLUSH and REQ_FUA bits as they sit | ||
54 | directly below the submit_bio interface. For remapping drivers the REQ_FUA | ||
55 | bits need to be propagated to underlying devices, and a global flush needs | ||
56 | to be implemented for bios with the REQ_FLUSH bit set. For real device | ||
57 | drivers that do not have a volatile cache the REQ_FLUSH and REQ_FUA bits | ||
58 | on non-empty bios can simply be ignored, and REQ_FLUSH requests without | ||
59 | data can be completed successfully without doing any work. Drivers for | ||
60 | devices with volatile caches need to implement the support for these | ||
61 | flags themselves without any help from the block layer. | ||
62 | |||
63 | |||
64 | Implementation details for request_fn based block drivers | ||
65 | -------------------------------------------------------------- | ||
66 | |||
67 | For devices that do not support volatile write caches there is no driver | ||
68 | support required, the block layer completes empty REQ_FLUSH requests before | ||
69 | entering the driver and strips off the REQ_FLUSH and REQ_FUA bits from | ||
70 | requests that have a payload. For devices with volatile write caches the | ||
71 | driver needs to tell the block layer that it supports flushing caches by | ||
72 | doing: | ||
73 | |||
74 | blk_queue_flush(sdkp->disk->queue, REQ_FLUSH); | ||
75 | |||
76 | and handle empty REQ_FLUSH requests in its prep_fn/request_fn. Note that | ||
77 | REQ_FLUSH requests with a payload are automatically turned into a sequence | ||
78 | of an empty REQ_FLUSH request followed by the actual write by the block | ||
79 | layer. For devices that also support the FUA bit the block layer needs | ||
80 | to be told to pass through the REQ_FUA bit using: | ||
81 | |||
82 | blk_queue_flush(sdkp->disk->queue, REQ_FLUSH | REQ_FUA); | ||
83 | |||
84 | and the driver must handle write requests that have the REQ_FUA bit set | ||
85 | in prep_fn/request_fn. If the FUA bit is not natively supported the block | ||
86 | layer turns it into an empty REQ_FLUSH request after the actual write. | ||
diff --git a/Documentation/cgroups/blkio-controller.txt b/Documentation/cgroups/blkio-controller.txt index 48e0b21b0059..d6da611f8f63 100644 --- a/Documentation/cgroups/blkio-controller.txt +++ b/Documentation/cgroups/blkio-controller.txt | |||
@@ -8,12 +8,17 @@ both at leaf nodes as well as at intermediate nodes in a storage hierarchy. | |||
8 | Plan is to use the same cgroup based management interface for blkio controller | 8 | Plan is to use the same cgroup based management interface for blkio controller |
9 | and based on user options switch IO policies in the background. | 9 | and based on user options switch IO policies in the background. |
10 | 10 | ||
11 | In the first phase, this patchset implements proportional weight time based | 11 | Currently two IO control policies are implemented. First one is proportional |
12 | division of disk policy. It is implemented in CFQ. Hence this policy takes | 12 | weight time based division of disk policy. It is implemented in CFQ. Hence |
13 | effect only on leaf nodes when CFQ is being used. | 13 | this policy takes effect only on leaf nodes when CFQ is being used. The second |
14 | one is throttling policy which can be used to specify upper IO rate limits | ||
15 | on devices. This policy is implemented in generic block layer and can be | ||
16 | used on leaf nodes as well as higher level logical devices like device mapper. | ||
14 | 17 | ||
15 | HOWTO | 18 | HOWTO |
16 | ===== | 19 | ===== |
20 | Proportional Weight division of bandwidth | ||
21 | ----------------------------------------- | ||
17 | You can do a very simple testing of running two dd threads in two different | 22 | You can do a very simple testing of running two dd threads in two different |
18 | cgroups. Here is what you can do. | 23 | cgroups. Here is what you can do. |
19 | 24 | ||
@@ -55,6 +60,35 @@ cgroups. Here is what you can do. | |||
55 | group dispatched to the disk. We provide fairness in terms of disk time, so | 60 | group dispatched to the disk. We provide fairness in terms of disk time, so |
56 | ideally io.disk_time of cgroups should be in proportion to the weight. | 61 | ideally io.disk_time of cgroups should be in proportion to the weight. |
57 | 62 | ||
63 | Throttling/Upper Limit policy | ||
64 | ----------------------------- | ||
65 | - Enable Block IO controller | ||
66 | CONFIG_BLK_CGROUP=y | ||
67 | |||
68 | - Enable throttling in block layer | ||
69 | CONFIG_BLK_DEV_THROTTLING=y | ||
70 | |||
71 | - Mount blkio controller | ||
72 | mount -t cgroup -o blkio none /cgroup/blkio | ||
73 | |||
74 | - Specify a bandwidth rate on particular device for root group. The format | ||
75 | for policy is "<major>:<minor> <byes_per_second>". | ||
76 | |||
77 | echo "8:16 1048576" > /cgroup/blkio/blkio.read_bps_device | ||
78 | |||
79 | Above will put a limit of 1MB/second on reads happening for root group | ||
80 | on device having major/minor number 8:16. | ||
81 | |||
82 | - Run dd to read a file and see if rate is throttled to 1MB/s or not. | ||
83 | |||
84 | # dd if=/mnt/common/zerofile of=/dev/null bs=4K count=1024 | ||
85 | # iflag=direct | ||
86 | 1024+0 records in | ||
87 | 1024+0 records out | ||
88 | 4194304 bytes (4.2 MB) copied, 4.0001 s, 1.0 MB/s | ||
89 | |||
90 | Limits for writes can be put using blkio.write_bps_device file. | ||
91 | |||
58 | Various user visible config options | 92 | Various user visible config options |
59 | =================================== | 93 | =================================== |
60 | CONFIG_BLK_CGROUP | 94 | CONFIG_BLK_CGROUP |
@@ -68,8 +102,13 @@ CONFIG_CFQ_GROUP_IOSCHED | |||
68 | - Enables group scheduling in CFQ. Currently only 1 level of group | 102 | - Enables group scheduling in CFQ. Currently only 1 level of group |
69 | creation is allowed. | 103 | creation is allowed. |
70 | 104 | ||
105 | CONFIG_BLK_DEV_THROTTLING | ||
106 | - Enable block device throttling support in block layer. | ||
107 | |||
71 | Details of cgroup files | 108 | Details of cgroup files |
72 | ======================= | 109 | ======================= |
110 | Proportional weight policy files | ||
111 | -------------------------------- | ||
73 | - blkio.weight | 112 | - blkio.weight |
74 | - Specifies per cgroup weight. This is default weight of the group | 113 | - Specifies per cgroup weight. This is default weight of the group |
75 | on all the devices until and unless overridden by per device rule. | 114 | on all the devices until and unless overridden by per device rule. |
@@ -210,6 +249,67 @@ Details of cgroup files | |||
210 | and minor number of the device and third field specifies the number | 249 | and minor number of the device and third field specifies the number |
211 | of times a group was dequeued from a particular device. | 250 | of times a group was dequeued from a particular device. |
212 | 251 | ||
252 | Throttling/Upper limit policy files | ||
253 | ----------------------------------- | ||
254 | - blkio.throttle.read_bps_device | ||
255 | - Specifies upper limit on READ rate from the device. IO rate is | ||
256 | specified in bytes per second. Rules are per deivce. Following is | ||
257 | the format. | ||
258 | |||
259 | echo "<major>:<minor> <rate_bytes_per_second>" > /cgrp/blkio.read_bps_device | ||
260 | |||
261 | - blkio.throttle.write_bps_device | ||
262 | - Specifies upper limit on WRITE rate to the device. IO rate is | ||
263 | specified in bytes per second. Rules are per deivce. Following is | ||
264 | the format. | ||
265 | |||
266 | echo "<major>:<minor> <rate_bytes_per_second>" > /cgrp/blkio.write_bps_device | ||
267 | |||
268 | - blkio.throttle.read_iops_device | ||
269 | - Specifies upper limit on READ rate from the device. IO rate is | ||
270 | specified in IO per second. Rules are per deivce. Following is | ||
271 | the format. | ||
272 | |||
273 | echo "<major>:<minor> <rate_io_per_second>" > /cgrp/blkio.read_iops_device | ||
274 | |||
275 | - blkio.throttle.write_iops_device | ||
276 | - Specifies upper limit on WRITE rate to the device. IO rate is | ||
277 | specified in io per second. Rules are per deivce. Following is | ||
278 | the format. | ||
279 | |||
280 | echo "<major>:<minor> <rate_io_per_second>" > /cgrp/blkio.write_iops_device | ||
281 | |||
282 | Note: If both BW and IOPS rules are specified for a device, then IO is | ||
283 | subjectd to both the constraints. | ||
284 | |||
285 | - blkio.throttle.io_serviced | ||
286 | - Number of IOs (bio) completed to/from the disk by the group (as | ||
287 | seen by throttling policy). These are further divided by the type | ||
288 | of operation - read or write, sync or async. First two fields specify | ||
289 | the major and minor number of the device, third field specifies the | ||
290 | operation type and the fourth field specifies the number of IOs. | ||
291 | |||
292 | blkio.io_serviced does accounting as seen by CFQ and counts are in | ||
293 | number of requests (struct request). On the other hand, | ||
294 | blkio.throttle.io_serviced counts number of IO in terms of number | ||
295 | of bios as seen by throttling policy. These bios can later be | ||
296 | merged by elevator and total number of requests completed can be | ||
297 | lesser. | ||
298 | |||
299 | - blkio.throttle.io_service_bytes | ||
300 | - Number of bytes transferred to/from the disk by the group. These | ||
301 | are further divided by the type of operation - read or write, sync | ||
302 | or async. First two fields specify the major and minor number of the | ||
303 | device, third field specifies the operation type and the fourth field | ||
304 | specifies the number of bytes. | ||
305 | |||
306 | These numbers should roughly be same as blkio.io_service_bytes as | ||
307 | updated by CFQ. The difference between two is that | ||
308 | blkio.io_service_bytes will not be updated if CFQ is not operating | ||
309 | on request queue. | ||
310 | |||
311 | Common files among various policies | ||
312 | ----------------------------------- | ||
213 | - blkio.reset_stats | 313 | - blkio.reset_stats |
214 | - Writing an int to this file will result in resetting all the stats | 314 | - Writing an int to this file will result in resetting all the stats |
215 | for that cgroup. | 315 | for that cgroup. |
@@ -217,6 +317,7 @@ Details of cgroup files | |||
217 | CFQ sysfs tunable | 317 | CFQ sysfs tunable |
218 | ================= | 318 | ================= |
219 | /sys/block/<disk>/queue/iosched/group_isolation | 319 | /sys/block/<disk>/queue/iosched/group_isolation |
320 | ----------------------------------------------- | ||
220 | 321 | ||
221 | If group_isolation=1, it provides stronger isolation between groups at the | 322 | If group_isolation=1, it provides stronger isolation between groups at the |
222 | expense of throughput. By default group_isolation is 0. In general that | 323 | expense of throughput. By default group_isolation is 0. In general that |
@@ -243,6 +344,33 @@ By default one should run with group_isolation=0. If that is not sufficient | |||
243 | and one wants stronger isolation between groups, then set group_isolation=1 | 344 | and one wants stronger isolation between groups, then set group_isolation=1 |
244 | but this will come at cost of reduced throughput. | 345 | but this will come at cost of reduced throughput. |
245 | 346 | ||
347 | /sys/block/<disk>/queue/iosched/slice_idle | ||
348 | ------------------------------------------ | ||
349 | On a faster hardware CFQ can be slow, especially with sequential workload. | ||
350 | This happens because CFQ idles on a single queue and single queue might not | ||
351 | drive deeper request queue depths to keep the storage busy. In such scenarios | ||
352 | one can try setting slice_idle=0 and that would switch CFQ to IOPS | ||
353 | (IO operations per second) mode on NCQ supporting hardware. | ||
354 | |||
355 | That means CFQ will not idle between cfq queues of a cfq group and hence be | ||
356 | able to driver higher queue depth and achieve better throughput. That also | ||
357 | means that cfq provides fairness among groups in terms of IOPS and not in | ||
358 | terms of disk time. | ||
359 | |||
360 | /sys/block/<disk>/queue/iosched/group_idle | ||
361 | ------------------------------------------ | ||
362 | If one disables idling on individual cfq queues and cfq service trees by | ||
363 | setting slice_idle=0, group_idle kicks in. That means CFQ will still idle | ||
364 | on the group in an attempt to provide fairness among groups. | ||
365 | |||
366 | By default group_idle is same as slice_idle and does not do anything if | ||
367 | slice_idle is enabled. | ||
368 | |||
369 | One can experience an overall throughput drop if you have created multiple | ||
370 | groups and put applications in that group which are not driving enough | ||
371 | IO to keep disk busy. In that case set group_idle=0, and CFQ will not idle | ||
372 | on individual groups and throughput should improve. | ||
373 | |||
246 | What works | 374 | What works |
247 | ========== | 375 | ========== |
248 | - Currently only sync IO queues are support. All the buffered writes are | 376 | - Currently only sync IO queues are support. All the buffered writes are |
diff --git a/Documentation/cpu-hotplug.txt b/Documentation/cpu-hotplug.txt index a99d7031cdf9..45d5a217484f 100644 --- a/Documentation/cpu-hotplug.txt +++ b/Documentation/cpu-hotplug.txt | |||
@@ -2,7 +2,7 @@ | |||
2 | 2 | ||
3 | Maintainers: | 3 | Maintainers: |
4 | CPU Hotplug Core: | 4 | CPU Hotplug Core: |
5 | Rusty Russell <rusty@rustycorp.com.au> | 5 | Rusty Russell <rusty@rustcorp.com.au> |
6 | Srivatsa Vaddagiri <vatsa@in.ibm.com> | 6 | Srivatsa Vaddagiri <vatsa@in.ibm.com> |
7 | i386: | 7 | i386: |
8 | Zwane Mwaikambo <zwane@arm.linux.org.uk> | 8 | Zwane Mwaikambo <zwane@arm.linux.org.uk> |
diff --git a/Documentation/cputopology.txt b/Documentation/cputopology.txt index f1c5c4bccd3e..902d3151f527 100644 --- a/Documentation/cputopology.txt +++ b/Documentation/cputopology.txt | |||
@@ -14,25 +14,39 @@ to /proc/cpuinfo. | |||
14 | identifier (rather than the kernel's). The actual value is | 14 | identifier (rather than the kernel's). The actual value is |
15 | architecture and platform dependent. | 15 | architecture and platform dependent. |
16 | 16 | ||
17 | 3) /sys/devices/system/cpu/cpuX/topology/thread_siblings: | 17 | 3) /sys/devices/system/cpu/cpuX/topology/book_id: |
18 | |||
19 | the book ID of cpuX. Typically it is the hardware platform's | ||
20 | identifier (rather than the kernel's). The actual value is | ||
21 | architecture and platform dependent. | ||
22 | |||
23 | 4) /sys/devices/system/cpu/cpuX/topology/thread_siblings: | ||
18 | 24 | ||
19 | internel kernel map of cpuX's hardware threads within the same | 25 | internel kernel map of cpuX's hardware threads within the same |
20 | core as cpuX | 26 | core as cpuX |
21 | 27 | ||
22 | 4) /sys/devices/system/cpu/cpuX/topology/core_siblings: | 28 | 5) /sys/devices/system/cpu/cpuX/topology/core_siblings: |
23 | 29 | ||
24 | internal kernel map of cpuX's hardware threads within the same | 30 | internal kernel map of cpuX's hardware threads within the same |
25 | physical_package_id. | 31 | physical_package_id. |
26 | 32 | ||
33 | 6) /sys/devices/system/cpu/cpuX/topology/book_siblings: | ||
34 | |||
35 | internal kernel map of cpuX's hardware threads within the same | ||
36 | book_id. | ||
37 | |||
27 | To implement it in an architecture-neutral way, a new source file, | 38 | To implement it in an architecture-neutral way, a new source file, |
28 | drivers/base/topology.c, is to export the 4 attributes. | 39 | drivers/base/topology.c, is to export the 4 or 6 attributes. The two book |
40 | related sysfs files will only be created if CONFIG_SCHED_BOOK is selected. | ||
29 | 41 | ||
30 | For an architecture to support this feature, it must define some of | 42 | For an architecture to support this feature, it must define some of |
31 | these macros in include/asm-XXX/topology.h: | 43 | these macros in include/asm-XXX/topology.h: |
32 | #define topology_physical_package_id(cpu) | 44 | #define topology_physical_package_id(cpu) |
33 | #define topology_core_id(cpu) | 45 | #define topology_core_id(cpu) |
46 | #define topology_book_id(cpu) | ||
34 | #define topology_thread_cpumask(cpu) | 47 | #define topology_thread_cpumask(cpu) |
35 | #define topology_core_cpumask(cpu) | 48 | #define topology_core_cpumask(cpu) |
49 | #define topology_book_cpumask(cpu) | ||
36 | 50 | ||
37 | The type of **_id is int. | 51 | The type of **_id is int. |
38 | The type of siblings is (const) struct cpumask *. | 52 | The type of siblings is (const) struct cpumask *. |
@@ -45,6 +59,9 @@ not defined by include/asm-XXX/topology.h: | |||
45 | 3) thread_siblings: just the given CPU | 59 | 3) thread_siblings: just the given CPU |
46 | 4) core_siblings: just the given CPU | 60 | 4) core_siblings: just the given CPU |
47 | 61 | ||
62 | For architectures that don't support books (CONFIG_SCHED_BOOK) there are no | ||
63 | default definitions for topology_book_id() and topology_book_cpumask(). | ||
64 | |||
48 | Additionally, CPU topology information is provided under | 65 | Additionally, CPU topology information is provided under |
49 | /sys/devices/system/cpu and includes these files. The internal | 66 | /sys/devices/system/cpu and includes these files. The internal |
50 | source for the output is in brackets ("[]"). | 67 | source for the output is in brackets ("[]"). |
diff --git a/Documentation/devices.txt b/Documentation/devices.txt index f2da781705b2..c58abf1ccc71 100644 --- a/Documentation/devices.txt +++ b/Documentation/devices.txt | |||
@@ -239,6 +239,7 @@ Your cooperation is appreciated. | |||
239 | 0 = /dev/tty Current TTY device | 239 | 0 = /dev/tty Current TTY device |
240 | 1 = /dev/console System console | 240 | 1 = /dev/console System console |
241 | 2 = /dev/ptmx PTY master multiplex | 241 | 2 = /dev/ptmx PTY master multiplex |
242 | 3 = /dev/ttyprintk User messages via printk TTY device | ||
242 | 64 = /dev/cua0 Callout device for ttyS0 | 243 | 64 = /dev/cua0 Callout device for ttyS0 |
243 | ... | 244 | ... |
244 | 255 = /dev/cua191 Callout device for ttyS191 | 245 | 255 = /dev/cua191 Callout device for ttyS191 |
@@ -445,6 +446,7 @@ Your cooperation is appreciated. | |||
445 | 233 = /dev/kmview View-OS A process with a view | 446 | 233 = /dev/kmview View-OS A process with a view |
446 | 234 = /dev/btrfs-control Btrfs control device | 447 | 234 = /dev/btrfs-control Btrfs control device |
447 | 235 = /dev/autofs Autofs control device | 448 | 235 = /dev/autofs Autofs control device |
449 | 236 = /dev/mapper/control Device-Mapper control device | ||
448 | 240-254 Reserved for local use | 450 | 240-254 Reserved for local use |
449 | 255 Reserved for MISC_DYNAMIC_MINOR | 451 | 255 Reserved for MISC_DYNAMIC_MINOR |
450 | 452 | ||
@@ -2552,7 +2554,10 @@ Your cooperation is appreciated. | |||
2552 | 175 = /dev/usb/legousbtower15 16th USB Legotower device | 2554 | 175 = /dev/usb/legousbtower15 16th USB Legotower device |
2553 | 176 = /dev/usb/usbtmc1 First USB TMC device | 2555 | 176 = /dev/usb/usbtmc1 First USB TMC device |
2554 | ... | 2556 | ... |
2555 | 192 = /dev/usb/usbtmc16 16th USB TMC device | 2557 | 191 = /dev/usb/usbtmc16 16th USB TMC device |
2558 | 192 = /dev/usb/yurex1 First USB Yurex device | ||
2559 | ... | ||
2560 | 209 = /dev/usb/yurex16 16th USB Yurex device | ||
2556 | 240 = /dev/usb/dabusb0 First daubusb device | 2561 | 240 = /dev/usb/dabusb0 First daubusb device |
2557 | ... | 2562 | ... |
2558 | 243 = /dev/usb/dabusb3 Fourth dabusb device | 2563 | 243 = /dev/usb/dabusb3 Fourth dabusb device |
diff --git a/Documentation/dynamic-debug-howto.txt b/Documentation/dynamic-debug-howto.txt index 674c5663d346..58ea64a96165 100644 --- a/Documentation/dynamic-debug-howto.txt +++ b/Documentation/dynamic-debug-howto.txt | |||
@@ -24,7 +24,7 @@ Dynamic debug has even more useful features: | |||
24 | read to display the complete list of known debug statements, to help guide you | 24 | read to display the complete list of known debug statements, to help guide you |
25 | 25 | ||
26 | Controlling dynamic debug Behaviour | 26 | Controlling dynamic debug Behaviour |
27 | =============================== | 27 | =================================== |
28 | 28 | ||
29 | The behaviour of pr_debug()/dev_debug()s are controlled via writing to a | 29 | The behaviour of pr_debug()/dev_debug()s are controlled via writing to a |
30 | control file in the 'debugfs' filesystem. Thus, you must first mount the debugfs | 30 | control file in the 'debugfs' filesystem. Thus, you must first mount the debugfs |
@@ -212,6 +212,26 @@ Note the regexp ^[-+=][scp]+$ matches a flags specification. | |||
212 | Note also that there is no convenient syntax to remove all | 212 | Note also that there is no convenient syntax to remove all |
213 | the flags at once, you need to use "-psc". | 213 | the flags at once, you need to use "-psc". |
214 | 214 | ||
215 | |||
216 | Debug messages during boot process | ||
217 | ================================== | ||
218 | |||
219 | To be able to activate debug messages during the boot process, | ||
220 | even before userspace and debugfs exists, use the boot parameter: | ||
221 | ddebug_query="QUERY" | ||
222 | |||
223 | QUERY follows the syntax described above, but must not exceed 1023 | ||
224 | characters. The enablement of debug messages is done as an arch_initcall. | ||
225 | Thus you can enable debug messages in all code processed after this | ||
226 | arch_initcall via this boot parameter. | ||
227 | On an x86 system for example ACPI enablement is a subsys_initcall and | ||
228 | ddebug_query="file ec.c +p" | ||
229 | will show early Embedded Controller transactions during ACPI setup if | ||
230 | your machine (typically a laptop) has an Embedded Controller. | ||
231 | PCI (or other devices) initialization also is a hot candidate for using | ||
232 | this boot parameter for debugging purposes. | ||
233 | |||
234 | |||
215 | Examples | 235 | Examples |
216 | ======== | 236 | ======== |
217 | 237 | ||
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt index b16cbe4152ea..9961f1564d22 100644 --- a/Documentation/feature-removal-schedule.txt +++ b/Documentation/feature-removal-schedule.txt | |||
@@ -386,34 +386,6 @@ Who: Tejun Heo <tj@kernel.org> | |||
386 | 386 | ||
387 | ---------------------------- | 387 | ---------------------------- |
388 | 388 | ||
389 | What: Support for VMware's guest paravirtuliazation technique [VMI] will be | ||
390 | dropped. | ||
391 | When: 2.6.37 or earlier. | ||
392 | Why: With the recent innovations in CPU hardware acceleration technologies | ||
393 | from Intel and AMD, VMware ran a few experiments to compare these | ||
394 | techniques to guest paravirtualization technique on VMware's platform. | ||
395 | These hardware assisted virtualization techniques have outperformed the | ||
396 | performance benefits provided by VMI in most of the workloads. VMware | ||
397 | expects that these hardware features will be ubiquitous in a couple of | ||
398 | years, as a result, VMware has started a phased retirement of this | ||
399 | feature from the hypervisor. We will be removing this feature from the | ||
400 | Kernel too. Right now we are targeting 2.6.37 but can retire earlier if | ||
401 | technical reasons (read opportunity to remove major chunk of pvops) | ||
402 | arise. | ||
403 | |||
404 | Please note that VMI has always been an optimization and non-VMI kernels | ||
405 | still work fine on VMware's platform. | ||
406 | Latest versions of VMware's product which support VMI are, | ||
407 | Workstation 7.0 and VSphere 4.0 on ESX side, future maintainence | ||
408 | releases for these products will continue supporting VMI. | ||
409 | |||
410 | For more details about VMI retirement take a look at this, | ||
411 | http://blogs.vmware.com/guestosguide/2009/09/vmi-retirement.html | ||
412 | |||
413 | Who: Alok N Kataria <akataria@vmware.com> | ||
414 | |||
415 | ---------------------------- | ||
416 | |||
417 | What: Support for lcd_switch and display_get in asus-laptop driver | 389 | What: Support for lcd_switch and display_get in asus-laptop driver |
418 | When: March 2010 | 390 | When: March 2010 |
419 | Why: These two features use non-standard interfaces. There are the | 391 | Why: These two features use non-standard interfaces. There are the |
@@ -547,3 +519,29 @@ Why: superseded by acpi_sleep=nonvs | |||
547 | Who: Rafael J. Wysocki <rjw@sisk.pl> | 519 | Who: Rafael J. Wysocki <rjw@sisk.pl> |
548 | 520 | ||
549 | ---------------------------- | 521 | ---------------------------- |
522 | |||
523 | What: PCI DMA unmap state API | ||
524 | When: August 2012 | ||
525 | Why: PCI DMA unmap state API (include/linux/pci-dma.h) was replaced | ||
526 | with DMA unmap state API (DMA unmap state API can be used for | ||
527 | any bus). | ||
528 | Who: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> | ||
529 | |||
530 | ---------------------------- | ||
531 | |||
532 | What: DMA_xxBIT_MASK macros | ||
533 | When: Jun 2011 | ||
534 | Why: DMA_xxBIT_MASK macros were replaced with DMA_BIT_MASK() macros. | ||
535 | Who: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> | ||
536 | |||
537 | ---------------------------- | ||
538 | |||
539 | What: iwlwifi disable_hw_scan module parameters | ||
540 | When: 2.6.40 | ||
541 | Why: Hareware scan is the prefer method for iwlwifi devices for | ||
542 | scanning operation. Remove software scan support for all the | ||
543 | iwlwifi devices. | ||
544 | |||
545 | Who: Wey-Yi Guy <wey-yi.w.guy@intel.com> | ||
546 | |||
547 | ---------------------------- | ||
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index bbcc15651a21..2db4283efa8d 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking | |||
@@ -374,8 +374,6 @@ prototypes: | |||
374 | ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t); | 374 | ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t); |
375 | int (*readdir) (struct file *, void *, filldir_t); | 375 | int (*readdir) (struct file *, void *, filldir_t); |
376 | unsigned int (*poll) (struct file *, struct poll_table_struct *); | 376 | unsigned int (*poll) (struct file *, struct poll_table_struct *); |
377 | int (*ioctl) (struct inode *, struct file *, unsigned int, | ||
378 | unsigned long); | ||
379 | long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long); | 377 | long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long); |
380 | long (*compat_ioctl) (struct file *, unsigned int, unsigned long); | 378 | long (*compat_ioctl) (struct file *, unsigned int, unsigned long); |
381 | int (*mmap) (struct file *, struct vm_area_struct *); | 379 | int (*mmap) (struct file *, struct vm_area_struct *); |
@@ -409,8 +407,7 @@ write: no | |||
409 | aio_write: no | 407 | aio_write: no |
410 | readdir: no | 408 | readdir: no |
411 | poll: no | 409 | poll: no |
412 | ioctl: yes (see below) | 410 | unlocked_ioctl: no |
413 | unlocked_ioctl: no (see below) | ||
414 | compat_ioctl: no | 411 | compat_ioctl: no |
415 | mmap: no | 412 | mmap: no |
416 | open: no | 413 | open: no |
@@ -453,9 +450,6 @@ move ->readdir() to inode_operations and use a separate method for directory | |||
453 | anything that resembles union-mount we won't have a struct file for all | 450 | anything that resembles union-mount we won't have a struct file for all |
454 | components. And there are other reasons why the current interface is a mess... | 451 | components. And there are other reasons why the current interface is a mess... |
455 | 452 | ||
456 | ->ioctl() on regular files is superceded by the ->unlocked_ioctl() that | ||
457 | doesn't take the BKL. | ||
458 | |||
459 | ->read on directories probably must go away - we should just enforce -EISDIR | 453 | ->read on directories probably must go away - we should just enforce -EISDIR |
460 | in sys_read() and friends. | 454 | in sys_read() and friends. |
461 | 455 | ||
diff --git a/Documentation/filesystems/ocfs2.txt b/Documentation/filesystems/ocfs2.txt index 1f7ae144f6d8..5393e6611691 100644 --- a/Documentation/filesystems/ocfs2.txt +++ b/Documentation/filesystems/ocfs2.txt | |||
@@ -87,3 +87,10 @@ dir_resv_level= (*) By default, directory reservations will scale with file | |||
87 | reservations - users should rarely need to change this | 87 | reservations - users should rarely need to change this |
88 | value. If allocation reservations are turned off, this | 88 | value. If allocation reservations are turned off, this |
89 | option will have no effect. | 89 | option will have no effect. |
90 | coherency=full (*) Disallow concurrent O_DIRECT writes, cluster inode | ||
91 | lock will be taken to force other nodes drop cache, | ||
92 | therefore full cluster coherency is guaranteed even | ||
93 | for O_DIRECT writes. | ||
94 | coherency=buffered Allow concurrent O_DIRECT writes without EX lock among | ||
95 | nodes, which gains high performance at risk of getting | ||
96 | stale data on other nodes. | ||
diff --git a/Documentation/filesystems/squashfs.txt b/Documentation/filesystems/squashfs.txt index 203f7202cc9e..66699afd66ca 100644 --- a/Documentation/filesystems/squashfs.txt +++ b/Documentation/filesystems/squashfs.txt | |||
@@ -2,7 +2,7 @@ SQUASHFS 4.0 FILESYSTEM | |||
2 | ======================= | 2 | ======================= |
3 | 3 | ||
4 | Squashfs is a compressed read-only filesystem for Linux. | 4 | Squashfs is a compressed read-only filesystem for Linux. |
5 | It uses zlib compression to compress files, inodes and directories. | 5 | It uses zlib/lzo compression to compress files, inodes and directories. |
6 | Inodes in the system are very small and all blocks are packed to minimise | 6 | Inodes in the system are very small and all blocks are packed to minimise |
7 | data overhead. Block sizes greater than 4K are supported up to a maximum | 7 | data overhead. Block sizes greater than 4K are supported up to a maximum |
8 | of 1Mbytes (default block size 128K). | 8 | of 1Mbytes (default block size 128K). |
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index 94677e7dcb13..ed7e5efc06d8 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt | |||
@@ -727,7 +727,6 @@ struct file_operations { | |||
727 | ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t); | 727 | ssize_t (*aio_write) (struct kiocb *, const struct iovec *, unsigned long, loff_t); |
728 | int (*readdir) (struct file *, void *, filldir_t); | 728 | int (*readdir) (struct file *, void *, filldir_t); |
729 | unsigned int (*poll) (struct file *, struct poll_table_struct *); | 729 | unsigned int (*poll) (struct file *, struct poll_table_struct *); |
730 | int (*ioctl) (struct inode *, struct file *, unsigned int, unsigned long); | ||
731 | long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long); | 730 | long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long); |
732 | long (*compat_ioctl) (struct file *, unsigned int, unsigned long); | 731 | long (*compat_ioctl) (struct file *, unsigned int, unsigned long); |
733 | int (*mmap) (struct file *, struct vm_area_struct *); | 732 | int (*mmap) (struct file *, struct vm_area_struct *); |
@@ -768,10 +767,7 @@ otherwise noted. | |||
768 | activity on this file and (optionally) go to sleep until there | 767 | activity on this file and (optionally) go to sleep until there |
769 | is activity. Called by the select(2) and poll(2) system calls | 768 | is activity. Called by the select(2) and poll(2) system calls |
770 | 769 | ||
771 | ioctl: called by the ioctl(2) system call | 770 | unlocked_ioctl: called by the ioctl(2) system call. |
772 | |||
773 | unlocked_ioctl: called by the ioctl(2) system call. Filesystems that do not | ||
774 | require the BKL should use this method instead of the ioctl() above. | ||
775 | 771 | ||
776 | compat_ioctl: called by the ioctl(2) system call when 32 bit system calls | 772 | compat_ioctl: called by the ioctl(2) system call when 32 bit system calls |
777 | are used on 64 bit kernels. | 773 | are used on 64 bit kernels. |
diff --git a/Documentation/gpio.txt b/Documentation/gpio.txt index c2c6e9b39bbe..9633da01ff46 100644 --- a/Documentation/gpio.txt +++ b/Documentation/gpio.txt | |||
@@ -109,17 +109,19 @@ use numbers 2000-2063 to identify GPIOs in a bank of I2C GPIO expanders. | |||
109 | 109 | ||
110 | If you want to initialize a structure with an invalid GPIO number, use | 110 | If you want to initialize a structure with an invalid GPIO number, use |
111 | some negative number (perhaps "-EINVAL"); that will never be valid. To | 111 | some negative number (perhaps "-EINVAL"); that will never be valid. To |
112 | test if a number could reference a GPIO, you may use this predicate: | 112 | test if such number from such a structure could reference a GPIO, you |
113 | may use this predicate: | ||
113 | 114 | ||
114 | int gpio_is_valid(int number); | 115 | int gpio_is_valid(int number); |
115 | 116 | ||
116 | A number that's not valid will be rejected by calls which may request | 117 | A number that's not valid will be rejected by calls which may request |
117 | or free GPIOs (see below). Other numbers may also be rejected; for | 118 | or free GPIOs (see below). Other numbers may also be rejected; for |
118 | example, a number might be valid but unused on a given board. | 119 | example, a number might be valid but temporarily unused on a given board. |
119 | |||
120 | Whether a platform supports multiple GPIO controllers is currently a | ||
121 | platform-specific implementation issue. | ||
122 | 120 | ||
121 | Whether a platform supports multiple GPIO controllers is a platform-specific | ||
122 | implementation issue, as are whether that support can leave "holes" in the space | ||
123 | of GPIO numbers, and whether new controllers can be added at runtime. Such issues | ||
124 | can affect things including whether adjacent GPIO numbers are both valid. | ||
123 | 125 | ||
124 | Using GPIOs | 126 | Using GPIOs |
125 | ----------- | 127 | ----------- |
@@ -158,10 +160,11 @@ and configure pullups/pulldowns appropriately.) | |||
158 | Spinlock-Safe GPIO access | 160 | Spinlock-Safe GPIO access |
159 | ------------------------- | 161 | ------------------------- |
160 | Most GPIO controllers can be accessed with memory read/write instructions. | 162 | Most GPIO controllers can be accessed with memory read/write instructions. |
161 | That doesn't need to sleep, and can safely be done from inside IRQ handlers. | 163 | Those don't need to sleep, and can safely be done from inside hard |
162 | (That includes hardirq contexts on RT kernels.) | 164 | (nonthreaded) IRQ handlers and similar contexts. |
163 | 165 | ||
164 | Use these calls to access such GPIOs: | 166 | Use the following calls to access such GPIOs, |
167 | for which gpio_cansleep() will always return false (see below): | ||
165 | 168 | ||
166 | /* GPIO INPUT: return zero or nonzero */ | 169 | /* GPIO INPUT: return zero or nonzero */ |
167 | int gpio_get_value(unsigned gpio); | 170 | int gpio_get_value(unsigned gpio); |
@@ -210,9 +213,31 @@ To access such GPIOs, a different set of accessors is defined: | |||
210 | /* GPIO OUTPUT, might sleep */ | 213 | /* GPIO OUTPUT, might sleep */ |
211 | void gpio_set_value_cansleep(unsigned gpio, int value); | 214 | void gpio_set_value_cansleep(unsigned gpio, int value); |
212 | 215 | ||
213 | Other than the fact that these calls might sleep, and will not be ignored | 216 | |
214 | for GPIOs that can't be accessed from IRQ handlers, these calls act the | 217 | Accessing such GPIOs requires a context which may sleep, for example |
215 | same as the spinlock-safe calls. | 218 | a threaded IRQ handler, and those accessors must be used instead of |
219 | spinlock-safe accessors without the cansleep() name suffix. | ||
220 | |||
221 | Other than the fact that these accessors might sleep, and will work | ||
222 | on GPIOs that can't be accessed from hardIRQ handlers, these calls act | ||
223 | the same as the spinlock-safe calls. | ||
224 | |||
225 | ** IN ADDITION ** calls to setup and configure such GPIOs must be made | ||
226 | from contexts which may sleep, since they may need to access the GPIO | ||
227 | controller chip too: (These setup calls are usually made from board | ||
228 | setup or driver probe/teardown code, so this is an easy constraint.) | ||
229 | |||
230 | gpio_direction_input() | ||
231 | gpio_direction_output() | ||
232 | gpio_request() | ||
233 | |||
234 | ## gpio_request_one() | ||
235 | ## gpio_request_array() | ||
236 | ## gpio_free_array() | ||
237 | |||
238 | gpio_free() | ||
239 | gpio_set_debounce() | ||
240 | |||
216 | 241 | ||
217 | 242 | ||
218 | Claiming and Releasing GPIOs | 243 | Claiming and Releasing GPIOs |
@@ -457,12 +482,16 @@ To support this framework, a platform's Kconfig will "select" either | |||
457 | ARCH_REQUIRE_GPIOLIB or ARCH_WANT_OPTIONAL_GPIOLIB | 482 | ARCH_REQUIRE_GPIOLIB or ARCH_WANT_OPTIONAL_GPIOLIB |
458 | and arrange that its <asm/gpio.h> includes <asm-generic/gpio.h> and defines | 483 | and arrange that its <asm/gpio.h> includes <asm-generic/gpio.h> and defines |
459 | three functions: gpio_get_value(), gpio_set_value(), and gpio_cansleep(). | 484 | three functions: gpio_get_value(), gpio_set_value(), and gpio_cansleep(). |
460 | They may also want to provide a custom value for ARCH_NR_GPIOS. | ||
461 | 485 | ||
462 | ARCH_REQUIRE_GPIOLIB means that the gpio-lib code will always get compiled | 486 | It may also provide a custom value for ARCH_NR_GPIOS, so that it better |
487 | reflects the number of GPIOs in actual use on that platform, without | ||
488 | wasting static table space. (It should count both built-in/SoC GPIOs and | ||
489 | also ones on GPIO expanders. | ||
490 | |||
491 | ARCH_REQUIRE_GPIOLIB means that the gpiolib code will always get compiled | ||
463 | into the kernel on that architecture. | 492 | into the kernel on that architecture. |
464 | 493 | ||
465 | ARCH_WANT_OPTIONAL_GPIOLIB means the gpio-lib code defaults to off and the user | 494 | ARCH_WANT_OPTIONAL_GPIOLIB means the gpiolib code defaults to off and the user |
466 | can enable it and build it into the kernel optionally. | 495 | can enable it and build it into the kernel optionally. |
467 | 496 | ||
468 | If neither of these options are selected, the platform does not support | 497 | If neither of these options are selected, the platform does not support |
diff --git a/Documentation/hwmon/emc2103 b/Documentation/hwmon/emc2103 new file mode 100644 index 000000000000..a12b2c127140 --- /dev/null +++ b/Documentation/hwmon/emc2103 | |||
@@ -0,0 +1,33 @@ | |||
1 | Kernel driver emc2103 | ||
2 | ====================== | ||
3 | |||
4 | Supported chips: | ||
5 | * SMSC EMC2103 | ||
6 | Addresses scanned: I2C 0x2e | ||
7 | Prefix: 'emc2103' | ||
8 | Datasheet: Not public | ||
9 | |||
10 | Authors: | ||
11 | Steve Glendinning <steve.glendinning@smsc.com> | ||
12 | |||
13 | Description | ||
14 | ----------- | ||
15 | |||
16 | The Standard Microsystems Corporation (SMSC) EMC2103 chips | ||
17 | contain up to 4 temperature sensors and a single fan controller. | ||
18 | |||
19 | Fan rotation speeds are reported in RPM (rotations per minute). An alarm is | ||
20 | triggered if the rotation speed has dropped below a programmable limit. Fan | ||
21 | readings can be divided by a programmable divider (1, 2, 4 or 8) to give | ||
22 | the readings more range or accuracy. Not all RPM values can accurately be | ||
23 | represented, so some rounding is done. With a divider of 1, the lowest | ||
24 | representable value is 480 RPM. | ||
25 | |||
26 | This driver supports RPM based control, to use this a fan target | ||
27 | should be written to fan1_target and pwm1_enable should be set to 3. | ||
28 | |||
29 | The 2103-2 and 2103-4 variants have a third temperature sensor, which can | ||
30 | be connected to two anti-parallel diodes. These values can be read | ||
31 | as temp3 and temp4. If only one diode is attached to this channel, temp4 | ||
32 | will show as "fault". The module parameter "apd=0" can be used to suppress | ||
33 | this 4th channel when anti-parallel diodes are not fitted. | ||
diff --git a/Documentation/hwmon/f71882fg b/Documentation/hwmon/f71882fg index 1a07fd674cd0..a7952c2bd959 100644 --- a/Documentation/hwmon/f71882fg +++ b/Documentation/hwmon/f71882fg | |||
@@ -2,10 +2,6 @@ Kernel driver f71882fg | |||
2 | ====================== | 2 | ====================== |
3 | 3 | ||
4 | Supported chips: | 4 | Supported chips: |
5 | * Fintek F71808E | ||
6 | Prefix: 'f71808fg' | ||
7 | Addresses scanned: none, address read from Super I/O config space | ||
8 | Datasheet: Not public | ||
9 | * Fintek F71858FG | 5 | * Fintek F71858FG |
10 | Prefix: 'f71858fg' | 6 | Prefix: 'f71858fg' |
11 | Addresses scanned: none, address read from Super I/O config space | 7 | Addresses scanned: none, address read from Super I/O config space |
diff --git a/Documentation/hwmon/ltc4245 b/Documentation/hwmon/ltc4245 index 86b5880d8502..b478b0864965 100644 --- a/Documentation/hwmon/ltc4245 +++ b/Documentation/hwmon/ltc4245 | |||
@@ -72,9 +72,31 @@ in6_min_alarm 5v output undervoltage alarm | |||
72 | in7_min_alarm 3v output undervoltage alarm | 72 | in7_min_alarm 3v output undervoltage alarm |
73 | in8_min_alarm Vee (-12v) output undervoltage alarm | 73 | in8_min_alarm Vee (-12v) output undervoltage alarm |
74 | 74 | ||
75 | in9_input GPIO voltage data | 75 | in9_input GPIO voltage data (see note 1) |
76 | in10_input GPIO voltage data (see note 1) | ||
77 | in11_input GPIO voltage data (see note 1) | ||
76 | 78 | ||
77 | power1_input 12v power usage (mW) | 79 | power1_input 12v power usage (mW) |
78 | power2_input 5v power usage (mW) | 80 | power2_input 5v power usage (mW) |
79 | power3_input 3v power usage (mW) | 81 | power3_input 3v power usage (mW) |
80 | power4_input Vee (-12v) power usage (mW) | 82 | power4_input Vee (-12v) power usage (mW) |
83 | |||
84 | |||
85 | Note 1 | ||
86 | ------ | ||
87 | |||
88 | If you have NOT configured the driver to sample all GPIO pins as analog | ||
89 | voltages, then the in10_input and in11_input sysfs attributes will not be | ||
90 | created. The driver will sample the GPIO pin that is currently connected to the | ||
91 | ADC as an analog voltage, and report the value in in9_input. | ||
92 | |||
93 | If you have configured the driver to sample all GPIO pins as analog voltages, | ||
94 | then they will be sampled in round-robin fashion. If userspace reads too | ||
95 | slowly, -EAGAIN will be returned when you read the sysfs attribute containing | ||
96 | the sensor reading. | ||
97 | |||
98 | The LTC4245 chip can be configured to sample all GPIO pins with two methods: | ||
99 | 1) platform data -- see include/linux/i2c/ltc4245.h | ||
100 | 2) OF device tree -- add the "ltc4245,use-extra-gpios" property to each chip | ||
101 | |||
102 | The default mode of operation is to sample a single GPIO pin. | ||
diff --git a/Documentation/hwmon/pc87427 b/Documentation/hwmon/pc87427 index db5cc1227a83..8fdd08c9e48b 100644 --- a/Documentation/hwmon/pc87427 +++ b/Documentation/hwmon/pc87427 | |||
@@ -18,10 +18,11 @@ Description | |||
18 | 18 | ||
19 | The National Semiconductor Super I/O chip includes complete hardware | 19 | The National Semiconductor Super I/O chip includes complete hardware |
20 | monitoring capabilities. It can monitor up to 18 voltages, 8 fans and | 20 | monitoring capabilities. It can monitor up to 18 voltages, 8 fans and |
21 | 6 temperature sensors. Only the fans are supported at the moment. | 21 | 6 temperature sensors. Only the fans and temperatures are supported at |
22 | the moment, voltages aren't. | ||
22 | 23 | ||
23 | This chip also has fan controlling features, which are not yet supported | 24 | This chip also has fan controlling features (up to 4 PWM outputs), |
24 | by this driver either. | 25 | which are partly supported by this driver. |
25 | 26 | ||
26 | The driver assumes that no more than one chip is present, which seems | 27 | The driver assumes that no more than one chip is present, which seems |
27 | reasonable. | 28 | reasonable. |
@@ -36,3 +37,23 @@ signal. Speeds down to 83 RPM can be measured. | |||
36 | An alarm is triggered if the rotation speed drops below a programmable | 37 | An alarm is triggered if the rotation speed drops below a programmable |
37 | limit. Another alarm is triggered if the speed is too low to be measured | 38 | limit. Another alarm is triggered if the speed is too low to be measured |
38 | (including stalled or missing fan). | 39 | (including stalled or missing fan). |
40 | |||
41 | |||
42 | Fan Speed Control | ||
43 | ----------------- | ||
44 | |||
45 | Fan speed can be controlled by PWM outputs. There are 4 possible modes: | ||
46 | always off, always on, manual and automatic. The latter isn't supported | ||
47 | by the driver: you can only return to that mode if it was the original | ||
48 | setting, and the configuration interface is missing. | ||
49 | |||
50 | |||
51 | Temperature Monitoring | ||
52 | ---------------------- | ||
53 | |||
54 | The PC87427 relies on external sensors (following the SensorPath | ||
55 | standard), so the resolution and range depend on the type of sensor | ||
56 | connected. The integer part can be 8-bit or 9-bit, and can be signed or | ||
57 | not. I couldn't find a way to figure out the external sensor data | ||
58 | temperature format, so user-space adjustment (typically by a factor 2) | ||
59 | may be required. | ||
diff --git a/Documentation/hwmon/sysfs-interface b/Documentation/hwmon/sysfs-interface index d4e2917c6f18..48ceabedf55d 100644 --- a/Documentation/hwmon/sysfs-interface +++ b/Documentation/hwmon/sysfs-interface | |||
@@ -91,12 +91,11 @@ name The chip name. | |||
91 | I2C devices get this attribute created automatically. | 91 | I2C devices get this attribute created automatically. |
92 | RO | 92 | RO |
93 | 93 | ||
94 | update_rate The rate at which the chip will update readings. | 94 | update_interval The interval at which the chip will update readings. |
95 | Unit: millisecond | 95 | Unit: millisecond |
96 | RW | 96 | RW |
97 | Some devices have a variable update rate. This attribute | 97 | Some devices have a variable update rate or interval. |
98 | can be used to change the update rate to the desired | 98 | This attribute can be used to change it to the desired value. |
99 | frequency. | ||
100 | 99 | ||
101 | 100 | ||
102 | ************ | 101 | ************ |
@@ -107,10 +106,24 @@ in[0-*]_min Voltage min value. | |||
107 | Unit: millivolt | 106 | Unit: millivolt |
108 | RW | 107 | RW |
109 | 108 | ||
109 | in[0-*]_lcrit Voltage critical min value. | ||
110 | Unit: millivolt | ||
111 | RW | ||
112 | If voltage drops to or below this limit, the system may | ||
113 | take drastic action such as power down or reset. At the very | ||
114 | least, it should report a fault. | ||
115 | |||
110 | in[0-*]_max Voltage max value. | 116 | in[0-*]_max Voltage max value. |
111 | Unit: millivolt | 117 | Unit: millivolt |
112 | RW | 118 | RW |
113 | 119 | ||
120 | in[0-*]_crit Voltage critical max value. | ||
121 | Unit: millivolt | ||
122 | RW | ||
123 | If voltage reaches or exceeds this limit, the system may | ||
124 | take drastic action such as power down or reset. At the very | ||
125 | least, it should report a fault. | ||
126 | |||
114 | in[0-*]_input Voltage input value. | 127 | in[0-*]_input Voltage input value. |
115 | Unit: millivolt | 128 | Unit: millivolt |
116 | RO | 129 | RO |
@@ -284,7 +297,7 @@ temp[1-*]_input Temperature input value. | |||
284 | Unit: millidegree Celsius | 297 | Unit: millidegree Celsius |
285 | RO | 298 | RO |
286 | 299 | ||
287 | temp[1-*]_crit Temperature critical value, typically greater than | 300 | temp[1-*]_crit Temperature critical max value, typically greater than |
288 | corresponding temp_max values. | 301 | corresponding temp_max values. |
289 | Unit: millidegree Celsius | 302 | Unit: millidegree Celsius |
290 | RW | 303 | RW |
@@ -296,6 +309,11 @@ temp[1-*]_crit_hyst | |||
296 | from the critical value. | 309 | from the critical value. |
297 | RW | 310 | RW |
298 | 311 | ||
312 | temp[1-*]_lcrit Temperature critical min value, typically lower than | ||
313 | corresponding temp_min values. | ||
314 | Unit: millidegree Celsius | ||
315 | RW | ||
316 | |||
299 | temp[1-*]_offset | 317 | temp[1-*]_offset |
300 | Temperature offset which is added to the temperature reading | 318 | Temperature offset which is added to the temperature reading |
301 | by the chip. | 319 | by the chip. |
@@ -344,9 +362,6 @@ Also see the Alarms section for status flags associated with temperatures. | |||
344 | * Currents * | 362 | * Currents * |
345 | ************ | 363 | ************ |
346 | 364 | ||
347 | Note that no known chip provides current measurements as of writing, | ||
348 | so this part is theoretical, so to say. | ||
349 | |||
350 | curr[1-*]_max Current max value | 365 | curr[1-*]_max Current max value |
351 | Unit: milliampere | 366 | Unit: milliampere |
352 | RW | 367 | RW |
@@ -471,6 +486,7 @@ limit-related alarms, not both. The driver should just reflect the hardware | |||
471 | implementation. | 486 | implementation. |
472 | 487 | ||
473 | in[0-*]_alarm | 488 | in[0-*]_alarm |
489 | curr[1-*]_alarm | ||
474 | fan[1-*]_alarm | 490 | fan[1-*]_alarm |
475 | temp[1-*]_alarm | 491 | temp[1-*]_alarm |
476 | Channel alarm | 492 | Channel alarm |
@@ -482,6 +498,8 @@ OR | |||
482 | 498 | ||
483 | in[0-*]_min_alarm | 499 | in[0-*]_min_alarm |
484 | in[0-*]_max_alarm | 500 | in[0-*]_max_alarm |
501 | curr[1-*]_min_alarm | ||
502 | curr[1-*]_max_alarm | ||
485 | fan[1-*]_min_alarm | 503 | fan[1-*]_min_alarm |
486 | fan[1-*]_max_alarm | 504 | fan[1-*]_max_alarm |
487 | temp[1-*]_min_alarm | 505 | temp[1-*]_min_alarm |
@@ -497,7 +515,6 @@ to notify open diodes, unconnected fans etc. where the hardware | |||
497 | supports it. When this boolean has value 1, the measurement for that | 515 | supports it. When this boolean has value 1, the measurement for that |
498 | channel should not be trusted. | 516 | channel should not be trusted. |
499 | 517 | ||
500 | in[0-*]_fault | ||
501 | fan[1-*]_fault | 518 | fan[1-*]_fault |
502 | temp[1-*]_fault | 519 | temp[1-*]_fault |
503 | Input fault condition | 520 | Input fault condition |
@@ -513,6 +530,7 @@ beep_enable Master beep enable | |||
513 | RW | 530 | RW |
514 | 531 | ||
515 | in[0-*]_beep | 532 | in[0-*]_beep |
533 | curr[1-*]_beep | ||
516 | fan[1-*]_beep | 534 | fan[1-*]_beep |
517 | temp[1-*]_beep | 535 | temp[1-*]_beep |
518 | Channel beep | 536 | Channel beep |
diff --git a/Documentation/hwmon/w83627ehf b/Documentation/hwmon/w83627ehf index b7e42ec4b26b..13d556112fc0 100644 --- a/Documentation/hwmon/w83627ehf +++ b/Documentation/hwmon/w83627ehf | |||
@@ -20,6 +20,10 @@ Supported chips: | |||
20 | Prefix: 'w83667hg' | 20 | Prefix: 'w83667hg' |
21 | Addresses scanned: ISA address retrieved from Super I/O registers | 21 | Addresses scanned: ISA address retrieved from Super I/O registers |
22 | Datasheet: not available | 22 | Datasheet: not available |
23 | * Winbond W83667HG-B | ||
24 | Prefix: 'w83667hg' | ||
25 | Addresses scanned: ISA address retrieved from Super I/O registers | ||
26 | Datasheet: Available from Nuvoton upon request | ||
23 | 27 | ||
24 | Authors: | 28 | Authors: |
25 | Jean Delvare <khali@linux-fr.org> | 29 | Jean Delvare <khali@linux-fr.org> |
@@ -32,8 +36,8 @@ Description | |||
32 | ----------- | 36 | ----------- |
33 | 37 | ||
34 | This driver implements support for the Winbond W83627EHF, W83627EHG, | 38 | This driver implements support for the Winbond W83627EHF, W83627EHG, |
35 | W83627DHG, W83627DHG-P and W83667HG super I/O chips. We will refer to them | 39 | W83627DHG, W83627DHG-P, W83667HG and W83667HG-B super I/O chips. |
36 | collectively as Winbond chips. | 40 | We will refer to them collectively as Winbond chips. |
37 | 41 | ||
38 | The chips implement three temperature sensors, five fan rotation | 42 | The chips implement three temperature sensors, five fan rotation |
39 | speed sensors, ten analog voltage sensors (only nine for the 627DHG), one | 43 | speed sensors, ten analog voltage sensors (only nine for the 627DHG), one |
@@ -68,14 +72,15 @@ follows: | |||
68 | temp1 -> pwm1 | 72 | temp1 -> pwm1 |
69 | temp2 -> pwm2 | 73 | temp2 -> pwm2 |
70 | temp3 -> pwm3 | 74 | temp3 -> pwm3 |
71 | prog -> pwm4 (not on 667HG; the programmable setting is not supported by | 75 | prog -> pwm4 (not on 667HG and 667HG-B; the programmable setting is not |
72 | the driver) | 76 | supported by the driver) |
73 | 77 | ||
74 | /sys files | 78 | /sys files |
75 | ---------- | 79 | ---------- |
76 | 80 | ||
77 | name - this is a standard hwmon device entry. For the W83627EHF and W83627EHG, | 81 | name - this is a standard hwmon device entry. For the W83627EHF and W83627EHG, |
78 | it is set to "w83627ehf" and for the W83627DHG it is set to "w83627dhg" | 82 | it is set to "w83627ehf", for the W83627DHG it is set to "w83627dhg", |
83 | and for the W83667HG it is set to "w83667hg". | ||
79 | 84 | ||
80 | pwm[1-4] - this file stores PWM duty cycle or DC value (fan speed) in range: | 85 | pwm[1-4] - this file stores PWM duty cycle or DC value (fan speed) in range: |
81 | 0 (stop) to 255 (full) | 86 | 0 (stop) to 255 (full) |
diff --git a/Documentation/i2c/instantiating-devices b/Documentation/i2c/instantiating-devices index e89490270aba..87da405a8597 100644 --- a/Documentation/i2c/instantiating-devices +++ b/Documentation/i2c/instantiating-devices | |||
@@ -102,7 +102,7 @@ static int __devinit usb_hcd_pnx4008_probe(struct platform_device *pdev) | |||
102 | memset(&i2c_info, 0, sizeof(struct i2c_board_info)); | 102 | memset(&i2c_info, 0, sizeof(struct i2c_board_info)); |
103 | strlcpy(i2c_info.name, "isp1301_pnx", I2C_NAME_SIZE); | 103 | strlcpy(i2c_info.name, "isp1301_pnx", I2C_NAME_SIZE); |
104 | isp1301_i2c_client = i2c_new_probed_device(i2c_adap, &i2c_info, | 104 | isp1301_i2c_client = i2c_new_probed_device(i2c_adap, &i2c_info, |
105 | normal_i2c); | 105 | normal_i2c, NULL); |
106 | i2c_put_adapter(i2c_adap); | 106 | i2c_put_adapter(i2c_adap); |
107 | (...) | 107 | (...) |
108 | } | 108 | } |
diff --git a/Documentation/input/ntrig.txt b/Documentation/input/ntrig.txt new file mode 100644 index 000000000000..be1fd981f73f --- /dev/null +++ b/Documentation/input/ntrig.txt | |||
@@ -0,0 +1,126 @@ | |||
1 | N-Trig touchscreen Driver | ||
2 | ------------------------- | ||
3 | Copyright (c) 2008-2010 Rafi Rubin <rafi@seas.upenn.edu> | ||
4 | Copyright (c) 2009-2010 Stephane Chatty | ||
5 | |||
6 | This driver provides support for N-Trig pen and multi-touch sensors. Single | ||
7 | and multi-touch events are translated to the appropriate protocols for | ||
8 | the hid and input systems. Pen events are sufficiently hid compliant and | ||
9 | are left to the hid core. The driver also provides additional filtering | ||
10 | and utility functions accessible with sysfs and module parameters. | ||
11 | |||
12 | This driver has been reported to work properly with multiple N-Trig devices | ||
13 | attached. | ||
14 | |||
15 | |||
16 | Parameters | ||
17 | ---------- | ||
18 | |||
19 | Note: values set at load time are global and will apply to all applicable | ||
20 | devices. Adjusting parameters with sysfs will override the load time values, | ||
21 | but only for that one device. | ||
22 | |||
23 | The following parameters are used to configure filters to reduce noise: | ||
24 | |||
25 | activate_slack number of fingers to ignore before processing events | ||
26 | |||
27 | activation_height size threshold to activate immediately | ||
28 | activation_width | ||
29 | |||
30 | min_height size threshold bellow which fingers are ignored | ||
31 | min_width both to decide activation and during activity | ||
32 | |||
33 | deactivate_slack the number of "no contact" frames to ignore before | ||
34 | propagating the end of activity events | ||
35 | |||
36 | When the last finger is removed from the device, it sends a number of empty | ||
37 | frames. By holding off on deactivation for a few frames we can tolerate false | ||
38 | erroneous disconnects, where the sensor may mistakenly not detect a finger that | ||
39 | is still present. Thus deactivate_slack addresses problems where a users might | ||
40 | see breaks in lines during drawing, or drop an object during a long drag. | ||
41 | |||
42 | |||
43 | Additional sysfs items | ||
44 | ---------------------- | ||
45 | |||
46 | These nodes just provide easy access to the ranges reported by the device. | ||
47 | sensor_logical_height the range for positions reported during activity | ||
48 | sensor_logical_width | ||
49 | |||
50 | sensor_physical_height internal ranges not used for normal events but | ||
51 | sensor_physical_width useful for tuning | ||
52 | |||
53 | All N-Trig devices with product id of 1 report events in the ranges of | ||
54 | X: 0-9600 | ||
55 | Y: 0-7200 | ||
56 | However not all of these devices have the same physical dimensions. Most | ||
57 | seem to be 12" sensors (Dell Latitude XT and XT2 and the HP TX2), and | ||
58 | at least one model (Dell Studio 17) has a 17" sensor. The ratio of physical | ||
59 | to logical sizes is used to adjust the size based filter parameters. | ||
60 | |||
61 | |||
62 | Filtering | ||
63 | --------- | ||
64 | |||
65 | With the release of the early multi-touch firmwares it became increasingly | ||
66 | obvious that these sensors were prone to erroneous events. Users reported | ||
67 | seeing both inappropriately dropped contact and ghosts, contacts reported | ||
68 | where no finger was actually touching the screen. | ||
69 | |||
70 | Deactivation slack helps prevent dropped contact for single touch use, but does | ||
71 | not address the problem of dropping one of more contacts while other contacts | ||
72 | are still active. Drops in the multi-touch context require additional | ||
73 | processing and should be handled in tandem with tacking. | ||
74 | |||
75 | As observed ghost contacts are similar to actual use of the sensor, but they | ||
76 | seem to have different profiles. Ghost activity typically shows up as small | ||
77 | short lived touches. As such, I assume that the longer the continuous stream | ||
78 | of events the more likely those events are from a real contact, and that the | ||
79 | larger the size of each contact the more likely it is real. Balancing the | ||
80 | goals of preventing ghosts and accepting real events quickly (to minimize | ||
81 | user observable latency), the filter accumulates confidence for incoming | ||
82 | events until it hits thresholds and begins propagating. In the interest in | ||
83 | minimizing stored state as well as the cost of operations to make a decision, | ||
84 | I've kept that decision simple. | ||
85 | |||
86 | Time is measured in terms of the number of fingers reported, not frames since | ||
87 | the probability of multiple simultaneous ghosts is expected to drop off | ||
88 | dramatically with increasing numbers. Rather than accumulate weight as a | ||
89 | function of size, I just use it as a binary threshold. A sufficiently large | ||
90 | contact immediately overrides the waiting period and leads to activation. | ||
91 | |||
92 | Setting the activation size thresholds to large values will result in deciding | ||
93 | primarily on activation slack. If you see longer lived ghosts, turning up the | ||
94 | activation slack while reducing the size thresholds may suffice to eliminate | ||
95 | the ghosts while keeping the screen quite responsive to firm taps. | ||
96 | |||
97 | Contacts continue to be filtered with min_height and min_width even after | ||
98 | the initial activation filter is satisfied. The intent is to provide | ||
99 | a mechanism for filtering out ghosts in the form of an extra finger while | ||
100 | you actually are using the screen. In practice this sort of ghost has | ||
101 | been far less problematic or relatively rare and I've left the defaults | ||
102 | set to 0 for both parameters, effectively turning off that filter. | ||
103 | |||
104 | I don't know what the optimal values are for these filters. If the defaults | ||
105 | don't work for you, please play with the parameters. If you do find other | ||
106 | values more comfortable, I would appreciate feedback. | ||
107 | |||
108 | The calibration of these devices does drift over time. If ghosts or contact | ||
109 | dropping worsen and interfere with the normal usage of your device, try | ||
110 | recalibrating it. | ||
111 | |||
112 | |||
113 | Calibration | ||
114 | ----------- | ||
115 | |||
116 | The N-Trig windows tools provide calibration and testing routines. Also an | ||
117 | unofficial unsupported set of user space tools including a calibrator is | ||
118 | available at: | ||
119 | http://code.launchpad.net/~rafi-seas/+junk/ntrig_calib | ||
120 | |||
121 | |||
122 | Tracking | ||
123 | -------- | ||
124 | |||
125 | As of yet, all tested N-Trig firmwares do not track fingers. When multiple | ||
126 | contacts are active they seem to be sorted primarily by Y position. | ||
diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt index c375313cb128..c787ae512120 100644 --- a/Documentation/kbuild/makefiles.txt +++ b/Documentation/kbuild/makefiles.txt | |||
@@ -45,7 +45,6 @@ This document describes the Linux kernel Makefiles. | |||
45 | --- 7.1 header-y | 45 | --- 7.1 header-y |
46 | --- 7.2 objhdr-y | 46 | --- 7.2 objhdr-y |
47 | --- 7.3 destination-y | 47 | --- 7.3 destination-y |
48 | --- 7.4 unifdef-y (deprecated) | ||
49 | 48 | ||
50 | === 8 Kbuild Variables | 49 | === 8 Kbuild Variables |
51 | === 9 Makefile language | 50 | === 9 Makefile language |
@@ -1245,11 +1244,6 @@ See subsequent chapter for the syntax of the Kbuild file. | |||
1245 | will be located in the directory "include/linux" when exported. | 1244 | will be located in the directory "include/linux" when exported. |
1246 | 1245 | ||
1247 | 1246 | ||
1248 | --- 7.4 unifdef-y (deprecated) | ||
1249 | |||
1250 | unifdef-y is deprecated. A direct replacement is header-y. | ||
1251 | |||
1252 | |||
1253 | === 8 Kbuild Variables | 1247 | === 8 Kbuild Variables |
1254 | 1248 | ||
1255 | The top Makefile exports the following variables: | 1249 | The top Makefile exports the following variables: |
diff --git a/Documentation/kernel-doc-nano-HOWTO.txt b/Documentation/kernel-doc-nano-HOWTO.txt index 27a52b35d55b..3d8a97747f77 100644 --- a/Documentation/kernel-doc-nano-HOWTO.txt +++ b/Documentation/kernel-doc-nano-HOWTO.txt | |||
@@ -345,5 +345,10 @@ documentation, in <filename>, for the functions listed. | |||
345 | section titled <section title> from <filename>. | 345 | section titled <section title> from <filename>. |
346 | Spaces are allowed in <section title>; do not quote the <section title>. | 346 | Spaces are allowed in <section title>; do not quote the <section title>. |
347 | 347 | ||
348 | !C<filename> is replaced by nothing, but makes the tools check that | ||
349 | all DOC: sections and documented functions, symbols, etc. are used. | ||
350 | This makes sense to use when you use !F/!P only and want to verify | ||
351 | that all documentation is included. | ||
352 | |||
348 | Tim. | 353 | Tim. |
349 | */ <twaugh@redhat.com> | 354 | */ <twaugh@redhat.com> |
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 8ed3a7772da1..0b6815504e6d 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt | |||
@@ -43,10 +43,11 @@ parameter is applicable: | |||
43 | AVR32 AVR32 architecture is enabled. | 43 | AVR32 AVR32 architecture is enabled. |
44 | AX25 Appropriate AX.25 support is enabled. | 44 | AX25 Appropriate AX.25 support is enabled. |
45 | BLACKFIN Blackfin architecture is enabled. | 45 | BLACKFIN Blackfin architecture is enabled. |
46 | DRM Direct Rendering Management support is enabled. | ||
47 | EDD BIOS Enhanced Disk Drive Services (EDD) is enabled | 46 | EDD BIOS Enhanced Disk Drive Services (EDD) is enabled |
48 | EFI EFI Partitioning (GPT) is enabled | 47 | EFI EFI Partitioning (GPT) is enabled |
49 | EIDE EIDE/ATAPI support is enabled. | 48 | EIDE EIDE/ATAPI support is enabled. |
49 | DRM Direct Rendering Management support is enabled. | ||
50 | DYNAMIC_DEBUG Build in debug messages and enable them at runtime | ||
50 | FB The frame buffer device is enabled. | 51 | FB The frame buffer device is enabled. |
51 | GCOV GCOV profiling is enabled. | 52 | GCOV GCOV profiling is enabled. |
52 | HW Appropriate hardware is enabled. | 53 | HW Appropriate hardware is enabled. |
@@ -88,8 +89,8 @@ parameter is applicable: | |||
88 | RAM RAM disk support is enabled. | 89 | RAM RAM disk support is enabled. |
89 | S390 S390 architecture is enabled. | 90 | S390 S390 architecture is enabled. |
90 | SCSI Appropriate SCSI support is enabled. | 91 | SCSI Appropriate SCSI support is enabled. |
91 | A lot of drivers has their options described inside of | 92 | A lot of drivers have their options described inside |
92 | Documentation/scsi/. | 93 | the Documentation/scsi/ sub-directory. |
93 | SECURITY Different security models are enabled. | 94 | SECURITY Different security models are enabled. |
94 | SELINUX SELinux support is enabled. | 95 | SELINUX SELinux support is enabled. |
95 | APPARMOR AppArmor support is enabled. | 96 | APPARMOR AppArmor support is enabled. |
@@ -284,27 +285,12 @@ and is between 256 and 4096 characters. It is defined in the file | |||
284 | add_efi_memmap [EFI; X86] Include EFI memory map in | 285 | add_efi_memmap [EFI; X86] Include EFI memory map in |
285 | kernel's map of available physical RAM. | 286 | kernel's map of available physical RAM. |
286 | 287 | ||
287 | advansys= [HW,SCSI] | ||
288 | See header of drivers/scsi/advansys.c. | ||
289 | |||
290 | agp= [AGP] | 288 | agp= [AGP] |
291 | { off | try_unsupported } | 289 | { off | try_unsupported } |
292 | off: disable AGP support | 290 | off: disable AGP support |
293 | try_unsupported: try to drive unsupported chipsets | 291 | try_unsupported: try to drive unsupported chipsets |
294 | (may crash computer or cause data corruption) | 292 | (may crash computer or cause data corruption) |
295 | 293 | ||
296 | aha152x= [HW,SCSI] | ||
297 | See Documentation/scsi/aha152x.txt. | ||
298 | |||
299 | aha1542= [HW,SCSI] | ||
300 | Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]] | ||
301 | |||
302 | aic7xxx= [HW,SCSI] | ||
303 | See Documentation/scsi/aic7xxx.txt. | ||
304 | |||
305 | aic79xx= [HW,SCSI] | ||
306 | See Documentation/scsi/aic79xx.txt. | ||
307 | |||
308 | ALSA [HW,ALSA] | 294 | ALSA [HW,ALSA] |
309 | See Documentation/sound/alsa/alsa-parameters.txt | 295 | See Documentation/sound/alsa/alsa-parameters.txt |
310 | 296 | ||
@@ -368,8 +354,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
368 | 354 | ||
369 | atarimouse= [HW,MOUSE] Atari Mouse | 355 | atarimouse= [HW,MOUSE] Atari Mouse |
370 | 356 | ||
371 | atascsi= [HW,SCSI] Atari SCSI | ||
372 | |||
373 | atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess, | 357 | atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess, |
374 | EzKey and similar keyboards | 358 | EzKey and similar keyboards |
375 | 359 | ||
@@ -419,10 +403,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
419 | bttv.pll= See Documentation/video4linux/bttv/Insmod-options | 403 | bttv.pll= See Documentation/video4linux/bttv/Insmod-options |
420 | bttv.tuner= and Documentation/video4linux/bttv/CARDLIST | 404 | bttv.tuner= and Documentation/video4linux/bttv/CARDLIST |
421 | 405 | ||
422 | BusLogic= [HW,SCSI] | ||
423 | See drivers/scsi/BusLogic.c, comment before function | ||
424 | BusLogic_ParseDriverOptions(). | ||
425 | |||
426 | c101= [NET] Moxa C101 synchronous serial card | 406 | c101= [NET] Moxa C101 synchronous serial card |
427 | 407 | ||
428 | cachesize= [BUGS=X86-32] Override level 2 CPU cache size detection. | 408 | cachesize= [BUGS=X86-32] Override level 2 CPU cache size detection. |
@@ -476,7 +456,7 @@ and is between 256 and 4096 characters. It is defined in the file | |||
476 | [ARM] imx_timer1,OSTS,netx_timer,mpu_timer2, | 456 | [ARM] imx_timer1,OSTS,netx_timer,mpu_timer2, |
477 | pxa_timer,timer3,32k_counter,timer0_1 | 457 | pxa_timer,timer3,32k_counter,timer0_1 |
478 | [AVR32] avr32 | 458 | [AVR32] avr32 |
479 | [X86-32] pit,hpet,tsc,vmi-timer; | 459 | [X86-32] pit,hpet,tsc; |
480 | scx200_hrt on Geode; cyclone on IBM x440 | 460 | scx200_hrt on Geode; cyclone on IBM x440 |
481 | [MIPS] MIPS | 461 | [MIPS] MIPS |
482 | [PARISC] cr16 | 462 | [PARISC] cr16 |
@@ -591,6 +571,10 @@ and is between 256 and 4096 characters. It is defined in the file | |||
591 | Format: <port#>,<type> | 571 | Format: <port#>,<type> |
592 | See also Documentation/input/joystick-parport.txt | 572 | See also Documentation/input/joystick-parport.txt |
593 | 573 | ||
574 | ddebug_query= [KNL,DYNAMIC_DEBUG] Enable debug messages at early boot | ||
575 | time. See Documentation/dynamic-debug-howto.txt for | ||
576 | details. | ||
577 | |||
594 | debug [KNL] Enable kernel debugging (events log level). | 578 | debug [KNL] Enable kernel debugging (events log level). |
595 | 579 | ||
596 | debug_locks_verbose= | 580 | debug_locks_verbose= |
@@ -671,8 +655,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
671 | 655 | ||
672 | dscc4.setup= [NET] | 656 | dscc4.setup= [NET] |
673 | 657 | ||
674 | dtc3181e= [HW,SCSI] | ||
675 | |||
676 | dynamic_printk Enables pr_debug()/dev_dbg() calls if | 658 | dynamic_printk Enables pr_debug()/dev_dbg() calls if |
677 | CONFIG_DYNAMIC_PRINTK_DEBUG has been enabled. | 659 | CONFIG_DYNAMIC_PRINTK_DEBUG has been enabled. |
678 | These can also be switched on/off via | 660 | These can also be switched on/off via |
@@ -713,8 +695,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
713 | This is desgined to be used in conjunction with | 695 | This is desgined to be used in conjunction with |
714 | the boot argument: earlyprintk=vga | 696 | the boot argument: earlyprintk=vga |
715 | 697 | ||
716 | eata= [HW,SCSI] | ||
717 | |||
718 | edd= [EDD] | 698 | edd= [EDD] |
719 | Format: {"off" | "on" | "skip[mbr]"} | 699 | Format: {"off" | "on" | "skip[mbr]"} |
720 | 700 | ||
@@ -770,12 +750,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
770 | Format: <interval>,<probability>,<space>,<times> | 750 | Format: <interval>,<probability>,<space>,<times> |
771 | See also /Documentation/fault-injection/. | 751 | See also /Documentation/fault-injection/. |
772 | 752 | ||
773 | fd_mcs= [HW,SCSI] | ||
774 | See header of drivers/scsi/fd_mcs.c. | ||
775 | |||
776 | fdomain= [HW,SCSI] | ||
777 | See header of drivers/scsi/fdomain.c. | ||
778 | |||
779 | floppy= [HW] | 753 | floppy= [HW] |
780 | See Documentation/blockdev/floppy.txt. | 754 | See Documentation/blockdev/floppy.txt. |
781 | 755 | ||
@@ -835,14 +809,9 @@ and is between 256 and 4096 characters. It is defined in the file | |||
835 | When zero, profiling data is discarded and associated | 809 | When zero, profiling data is discarded and associated |
836 | debugfs files are removed at module unload time. | 810 | debugfs files are removed at module unload time. |
837 | 811 | ||
838 | gdth= [HW,SCSI] | ||
839 | See header of drivers/scsi/gdth.c. | ||
840 | |||
841 | gpt [EFI] Forces disk with valid GPT signature but | 812 | gpt [EFI] Forces disk with valid GPT signature but |
842 | invalid Protective MBR to be treated as GPT. | 813 | invalid Protective MBR to be treated as GPT. |
843 | 814 | ||
844 | gvp11= [HW,SCSI] | ||
845 | |||
846 | hashdist= [KNL,NUMA] Large hashes allocated during boot | 815 | hashdist= [KNL,NUMA] Large hashes allocated during boot |
847 | are distributed across NUMA nodes. Defaults on | 816 | are distributed across NUMA nodes. Defaults on |
848 | for 64bit NUMA, off otherwise. | 817 | for 64bit NUMA, off otherwise. |
@@ -915,9 +884,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
915 | controller | 884 | controller |
916 | i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX | 885 | i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX |
917 | controllers | 886 | controllers |
918 | i8042.panicblink= | ||
919 | [HW] Frequency with which keyboard LEDs should blink | ||
920 | when kernel panics (default is 0.5 sec) | ||
921 | i8042.reset [HW] Reset the controller during init and cleanup | 887 | i8042.reset [HW] Reset the controller during init and cleanup |
922 | i8042.unlock [HW] Unlock (ignore) the keylock | 888 | i8042.unlock [HW] Unlock (ignore) the keylock |
923 | 889 | ||
@@ -934,9 +900,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
934 | i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN | 900 | i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN |
935 | capability is set. | 901 | capability is set. |
936 | 902 | ||
937 | ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter | ||
938 | See Documentation/mca.txt. | ||
939 | |||
940 | icn= [HW,ISDN] | 903 | icn= [HW,ISDN] |
941 | Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]] | 904 | Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]] |
942 | 905 | ||
@@ -986,9 +949,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
986 | programs exec'd, files mmap'd for exec, and all files | 949 | programs exec'd, files mmap'd for exec, and all files |
987 | opened for read by uid=0. | 950 | opened for read by uid=0. |
988 | 951 | ||
989 | in2000= [HW,SCSI] | ||
990 | See header of drivers/scsi/in2000.c. | ||
991 | |||
992 | init= [KNL] | 952 | init= [KNL] |
993 | Format: <full_path> | 953 | Format: <full_path> |
994 | Run specified binary instead of /sbin/init as init | 954 | Run specified binary instead of /sbin/init as init |
@@ -1026,6 +986,12 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1026 | result in a hardware IOTLB flush operation as opposed | 986 | result in a hardware IOTLB flush operation as opposed |
1027 | to batching them for performance. | 987 | to batching them for performance. |
1028 | 988 | ||
989 | intremap= [X86-64, Intel-IOMMU] | ||
990 | Format: { on (default) | off | nosid } | ||
991 | on enable Interrupt Remapping (default) | ||
992 | off disable Interrupt Remapping | ||
993 | nosid disable Source ID checking | ||
994 | |||
1029 | inttest= [IA64] | 995 | inttest= [IA64] |
1030 | 996 | ||
1031 | iomem= Disable strict checking of access to MMIO memory | 997 | iomem= Disable strict checking of access to MMIO memory |
@@ -1066,9 +1032,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1066 | See comment before ip2_setup() in | 1032 | See comment before ip2_setup() in |
1067 | drivers/char/ip2/ip2base.c. | 1033 | drivers/char/ip2/ip2base.c. |
1068 | 1034 | ||
1069 | ips= [HW,SCSI] Adaptec / IBM ServeRAID controller | ||
1070 | See header of drivers/scsi/ips.c. | ||
1071 | |||
1072 | irqfixup [HW] | 1035 | irqfixup [HW] |
1073 | When an interrupt is not handled search all handlers | 1036 | When an interrupt is not handled search all handlers |
1074 | for it. Intended to get systems with badly broken | 1037 | for it. Intended to get systems with badly broken |
@@ -1168,9 +1131,13 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1168 | kvm.oos_shadow= [KVM] Disable out-of-sync shadow paging. | 1131 | kvm.oos_shadow= [KVM] Disable out-of-sync shadow paging. |
1169 | Default is 1 (enabled) | 1132 | Default is 1 (enabled) |
1170 | 1133 | ||
1171 | kvm-amd.nested= [KVM,AMD] Allow nested virtualization in KVM/SVM. | 1134 | kvm.mmu_audit= [KVM] This is a R/W parameter which allows audit |
1135 | KVM MMU at runtime. | ||
1172 | Default is 0 (off) | 1136 | Default is 0 (off) |
1173 | 1137 | ||
1138 | kvm-amd.nested= [KVM,AMD] Allow nested virtualization in KVM/SVM. | ||
1139 | Default is 1 (enabled) | ||
1140 | |||
1174 | kvm-amd.npt= [KVM,AMD] Disable nested paging (virtualized MMU) | 1141 | kvm-amd.npt= [KVM,AMD] Disable nested paging (virtualized MMU) |
1175 | for all guests. | 1142 | for all guests. |
1176 | Default is 1 (enabled) if in 64bit or 32bit-PAE mode | 1143 | Default is 1 (enabled) if in 64bit or 32bit-PAE mode |
@@ -1344,9 +1311,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1344 | ltpc= [NET] | 1311 | ltpc= [NET] |
1345 | Format: <io>,<irq>,<dma> | 1312 | Format: <io>,<irq>,<dma> |
1346 | 1313 | ||
1347 | mac5380= [HW,SCSI] Format: | ||
1348 | <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags> | ||
1349 | |||
1350 | machvec= [IA64] Force the use of a particular machine-vector | 1314 | machvec= [IA64] Force the use of a particular machine-vector |
1351 | (machvec) in a generic kernel. | 1315 | (machvec) in a generic kernel. |
1352 | Example: machvec=hpzx1_swiotlb | 1316 | Example: machvec=hpzx1_swiotlb |
@@ -1368,13 +1332,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1368 | be mounted | 1332 | be mounted |
1369 | Format: <1-256> | 1333 | Format: <1-256> |
1370 | 1334 | ||
1371 | max_luns= [SCSI] Maximum number of LUNs to probe. | ||
1372 | Should be between 1 and 2^32-1. | ||
1373 | |||
1374 | max_report_luns= | ||
1375 | [SCSI] Maximum number of LUNs received. | ||
1376 | Should be between 1 and 16384. | ||
1377 | |||
1378 | mcatest= [IA-64] | 1335 | mcatest= [IA-64] |
1379 | 1336 | ||
1380 | mce [X86-32] Machine Check Exception | 1337 | mce [X86-32] Machine Check Exception |
@@ -1571,19 +1528,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1571 | 1528 | ||
1572 | n2= [NET] SDL Inc. RISCom/N2 synchronous serial card | 1529 | n2= [NET] SDL Inc. RISCom/N2 synchronous serial card |
1573 | 1530 | ||
1574 | NCR_D700= [HW,SCSI] | ||
1575 | See header of drivers/scsi/NCR_D700.c. | ||
1576 | |||
1577 | ncr5380= [HW,SCSI] | ||
1578 | |||
1579 | ncr53c400= [HW,SCSI] | ||
1580 | |||
1581 | ncr53c400a= [HW,SCSI] | ||
1582 | |||
1583 | ncr53c406a= [HW,SCSI] | ||
1584 | |||
1585 | ncr53c8xx= [HW,SCSI] | ||
1586 | |||
1587 | netdev= [NET] Network devices parameters | 1531 | netdev= [NET] Network devices parameters |
1588 | Format: <irq>,<io>,<mem_start>,<mem_end>,<name> | 1532 | Format: <irq>,<io>,<mem_start>,<mem_end>,<name> |
1589 | Note that mem_start is often overloaded to mean | 1533 | Note that mem_start is often overloaded to mean |
@@ -1752,11 +1696,14 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1752 | 1696 | ||
1753 | nointremap [X86-64, Intel-IOMMU] Do not enable interrupt | 1697 | nointremap [X86-64, Intel-IOMMU] Do not enable interrupt |
1754 | remapping. | 1698 | remapping. |
1699 | [Deprecated - use intremap=off] | ||
1755 | 1700 | ||
1756 | nointroute [IA-64] | 1701 | nointroute [IA-64] |
1757 | 1702 | ||
1758 | nojitter [IA64] Disables jitter checking for ITC timers. | 1703 | nojitter [IA64] Disables jitter checking for ITC timers. |
1759 | 1704 | ||
1705 | no-kvmclock [X86,KVM] Disable paravirtualized KVM clock driver | ||
1706 | |||
1760 | nolapic [X86-32,APIC] Do not enable or use the local APIC. | 1707 | nolapic [X86-32,APIC] Do not enable or use the local APIC. |
1761 | 1708 | ||
1762 | nolapic_timer [X86-32,APIC] Do not use the local APIC timer. | 1709 | nolapic_timer [X86-32,APIC] Do not use the local APIC timer. |
@@ -1862,10 +1809,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1862 | OSS [HW,OSS] | 1809 | OSS [HW,OSS] |
1863 | See Documentation/sound/oss/oss-parameters.txt | 1810 | See Documentation/sound/oss/oss-parameters.txt |
1864 | 1811 | ||
1865 | osst= [HW,SCSI] SCSI Tape Driver | ||
1866 | Format: <buffer_size>,<write_threshold> | ||
1867 | See also Documentation/scsi/st.txt. | ||
1868 | |||
1869 | panic= [KNL] Kernel behaviour on panic | 1812 | panic= [KNL] Kernel behaviour on panic |
1870 | Format: <timeout> | 1813 | Format: <timeout> |
1871 | 1814 | ||
@@ -1898,9 +1841,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
1898 | Currently this function knows 686a and 8231 chips. | 1841 | Currently this function knows 686a and 8231 chips. |
1899 | Format: [spp|ps2|epp|ecp|ecpepp] | 1842 | Format: [spp|ps2|epp|ecp|ecpepp] |
1900 | 1843 | ||
1901 | pas16= [HW,SCSI] | ||
1902 | See header of drivers/scsi/pas16.c. | ||
1903 | |||
1904 | pause_on_oops= | 1844 | pause_on_oops= |
1905 | Halt all CPUs after the first oops has been printed for | 1845 | Halt all CPUs after the first oops has been printed for |
1906 | the specified number of seconds. This is to be used if | 1846 | the specified number of seconds. This is to be used if |
@@ -2045,15 +1985,18 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2045 | force Enable ASPM even on devices that claim not to support it. | 1985 | force Enable ASPM even on devices that claim not to support it. |
2046 | WARNING: Forcing ASPM on may cause system lockups. | 1986 | WARNING: Forcing ASPM on may cause system lockups. |
2047 | 1987 | ||
1988 | pcie_ports= [PCIE] PCIe ports handling: | ||
1989 | auto Ask the BIOS whether or not to use native PCIe services | ||
1990 | associated with PCIe ports (PME, hot-plug, AER). Use | ||
1991 | them only if that is allowed by the BIOS. | ||
1992 | native Use native PCIe services associated with PCIe ports | ||
1993 | unconditionally. | ||
1994 | compat Treat PCIe ports as PCI-to-PCI bridges, disable the PCIe | ||
1995 | ports driver. | ||
1996 | |||
2048 | pcie_pme= [PCIE,PM] Native PCIe PME signaling options: | 1997 | pcie_pme= [PCIE,PM] Native PCIe PME signaling options: |
2049 | Format: {auto|force}[,nomsi] | ||
2050 | auto Use native PCIe PME signaling if the BIOS allows the | ||
2051 | kernel to control PCIe config registers of root ports. | ||
2052 | force Use native PCIe PME signaling even if the BIOS refuses | ||
2053 | to allow the kernel to control the relevant PCIe config | ||
2054 | registers. | ||
2055 | nomsi Do not use MSI for native PCIe PME signaling (this makes | 1998 | nomsi Do not use MSI for native PCIe PME signaling (this makes |
2056 | all PCIe root ports use INTx for everything). | 1999 | all PCIe root ports use INTx for all services). |
2057 | 2000 | ||
2058 | pcmv= [HW,PCMCIA] BadgePAD 4 | 2001 | pcmv= [HW,PCMCIA] BadgePAD 4 |
2059 | 2002 | ||
@@ -2221,6 +2164,11 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2221 | Reserves a hole at the top of the kernel virtual | 2164 | Reserves a hole at the top of the kernel virtual |
2222 | address space. | 2165 | address space. |
2223 | 2166 | ||
2167 | reservelow= [X86] | ||
2168 | Format: nn[K] | ||
2169 | Set the amount of memory to reserve for BIOS at | ||
2170 | the bottom of the address space. | ||
2171 | |||
2224 | reset_devices [KNL] Force drivers to reset the underlying device | 2172 | reset_devices [KNL] Force drivers to reset the underlying device |
2225 | during initialization. | 2173 | during initialization. |
2226 | 2174 | ||
@@ -2233,6 +2181,11 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2233 | in <PAGE_SIZE> units (needed only for swap files). | 2181 | in <PAGE_SIZE> units (needed only for swap files). |
2234 | See Documentation/power/swsusp-and-swap-files.txt | 2182 | See Documentation/power/swsusp-and-swap-files.txt |
2235 | 2183 | ||
2184 | hibernate= [HIBERNATION] | ||
2185 | noresume Don't check if there's a hibernation image | ||
2186 | present during boot. | ||
2187 | nocompress Don't compress/decompress hibernation images. | ||
2188 | |||
2236 | retain_initrd [RAM] Keep initrd memory after extraction | 2189 | retain_initrd [RAM] Keep initrd memory after extraction |
2237 | 2190 | ||
2238 | rhash_entries= [KNL,NET] | 2191 | rhash_entries= [KNL,NET] |
@@ -2267,30 +2220,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2267 | 2220 | ||
2268 | sched_debug [KNL] Enables verbose scheduler debug messages. | 2221 | sched_debug [KNL] Enables verbose scheduler debug messages. |
2269 | 2222 | ||
2270 | scsi_debug_*= [SCSI] | ||
2271 | See drivers/scsi/scsi_debug.c. | ||
2272 | |||
2273 | scsi_default_dev_flags= | ||
2274 | [SCSI] SCSI default device flags | ||
2275 | Format: <integer> | ||
2276 | |||
2277 | scsi_dev_flags= [SCSI] Black/white list entry for vendor and model | ||
2278 | Format: <vendor>:<model>:<flags> | ||
2279 | (flags are integer value) | ||
2280 | |||
2281 | scsi_logging_level= [SCSI] a bit mask of logging levels | ||
2282 | See drivers/scsi/scsi_logging.h for bits. Also | ||
2283 | settable via sysctl at dev.scsi.logging_level | ||
2284 | (/proc/sys/dev/scsi/logging_level). | ||
2285 | There is also a nice 'scsi_logging_level' script in the | ||
2286 | S390-tools package, available for download at | ||
2287 | http://www-128.ibm.com/developerworks/linux/linux390/s390-tools-1.5.4.html | ||
2288 | |||
2289 | scsi_mod.scan= [SCSI] sync (default) scans SCSI busses as they are | ||
2290 | discovered. async scans them in kernel threads, | ||
2291 | allowing boot to proceed. none ignores them, expecting | ||
2292 | user space to do the scan. | ||
2293 | |||
2294 | security= [SECURITY] Choose a security module to enable at boot. | 2223 | security= [SECURITY] Choose a security module to enable at boot. |
2295 | If this boot parameter is not specified, only the first | 2224 | If this boot parameter is not specified, only the first |
2296 | security module asking for security registration will be | 2225 | security module asking for security registration will be |
@@ -2324,9 +2253,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2324 | The parameter means the number of CPUs to show, | 2253 | The parameter means the number of CPUs to show, |
2325 | for example 1 means boot CPU only. | 2254 | for example 1 means boot CPU only. |
2326 | 2255 | ||
2327 | sim710= [SCSI,HW] | ||
2328 | See header of drivers/scsi/sim710.c. | ||
2329 | |||
2330 | simeth= [IA-64] | 2256 | simeth= [IA-64] |
2331 | simscsi= | 2257 | simscsi= |
2332 | 2258 | ||
@@ -2398,9 +2324,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2398 | spia_pedr= | 2324 | spia_pedr= |
2399 | spia_peddr= | 2325 | spia_peddr= |
2400 | 2326 | ||
2401 | st= [HW,SCSI] SCSI tape parameters (buffers, etc.) | ||
2402 | See Documentation/scsi/st.txt. | ||
2403 | |||
2404 | stacktrace [FTRACE] | 2327 | stacktrace [FTRACE] |
2405 | Enabled the stack tracer on boot up. | 2328 | Enabled the stack tracer on boot up. |
2406 | 2329 | ||
@@ -2458,8 +2381,14 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2458 | 2381 | ||
2459 | switches= [HW,M68k] | 2382 | switches= [HW,M68k] |
2460 | 2383 | ||
2461 | sym53c416= [HW,SCSI] | 2384 | sysfs.deprecated=0|1 [KNL] |
2462 | See header of drivers/scsi/sym53c416.c. | 2385 | Enable/disable old style sysfs layout for old udev |
2386 | on older distributions. When this option is enabled | ||
2387 | very new udev will not work anymore. When this option | ||
2388 | is disabled (or CONFIG_SYSFS_DEPRECATED not compiled) | ||
2389 | in older udev will not work anymore. | ||
2390 | Default depends on CONFIG_SYSFS_DEPRECATED_V2 set in | ||
2391 | the kernel configuration. | ||
2463 | 2392 | ||
2464 | sysrq_always_enabled | 2393 | sysrq_always_enabled |
2465 | [KNL] | 2394 | [KNL] |
@@ -2467,9 +2396,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2467 | neutralize any effect of /proc/sys/kernel/sysrq. | 2396 | neutralize any effect of /proc/sys/kernel/sysrq. |
2468 | Useful for debugging. | 2397 | Useful for debugging. |
2469 | 2398 | ||
2470 | t128= [HW,SCSI] | ||
2471 | See header of drivers/scsi/t128.c. | ||
2472 | |||
2473 | tdfx= [HW,DRM] | 2399 | tdfx= [HW,DRM] |
2474 | 2400 | ||
2475 | test_suspend= [SUSPEND] | 2401 | test_suspend= [SUSPEND] |
@@ -2506,10 +2432,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2506 | <deci-seconds>: poll all this frequency | 2432 | <deci-seconds>: poll all this frequency |
2507 | 0: no polling (default) | 2433 | 0: no polling (default) |
2508 | 2434 | ||
2509 | tmscsim= [HW,SCSI] | ||
2510 | See comment before function dc390_setup() in | ||
2511 | drivers/scsi/tmscsim.c. | ||
2512 | |||
2513 | topology= [S390] | 2435 | topology= [S390] |
2514 | Format: {off | on} | 2436 | Format: {off | on} |
2515 | Specify if the kernel should make use of the cpu | 2437 | Specify if the kernel should make use of the cpu |
@@ -2543,6 +2465,10 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2543 | disables clocksource verification at runtime. | 2465 | disables clocksource verification at runtime. |
2544 | Used to enable high-resolution timer mode on older | 2466 | Used to enable high-resolution timer mode on older |
2545 | hardware, and in virtualized environment. | 2467 | hardware, and in virtualized environment. |
2468 | [x86] noirqtime: Do not use TSC to do irq accounting. | ||
2469 | Used to run time disable IRQ_TIME_ACCOUNTING on any | ||
2470 | platforms where RDTSC is slow and this accounting | ||
2471 | can add overhead. | ||
2546 | 2472 | ||
2547 | turbografx.map[2|3]= [HW,JOY] | 2473 | turbografx.map[2|3]= [HW,JOY] |
2548 | TurboGraFX parallel port interface | 2474 | TurboGraFX parallel port interface |
@@ -2550,9 +2476,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2550 | <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7> | 2476 | <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7> |
2551 | See also Documentation/input/joystick-parport.txt | 2477 | See also Documentation/input/joystick-parport.txt |
2552 | 2478 | ||
2553 | u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter | ||
2554 | See header of drivers/scsi/u14-34f.c. | ||
2555 | |||
2556 | uhash_entries= [KNL,NET] | 2479 | uhash_entries= [KNL,NET] |
2557 | Set number of hash buckets for UDP/UDP-Lite connections | 2480 | Set number of hash buckets for UDP/UDP-Lite connections |
2558 | 2481 | ||
@@ -2718,12 +2641,6 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2718 | overridden by individual drivers. 0 will hide | 2641 | overridden by individual drivers. 0 will hide |
2719 | cursors, 1 will display them. | 2642 | cursors, 1 will display them. |
2720 | 2643 | ||
2721 | wd33c93= [HW,SCSI] | ||
2722 | See header of drivers/scsi/wd33c93.c. | ||
2723 | |||
2724 | wd7000= [HW,SCSI] | ||
2725 | See header of drivers/scsi/wd7000.c. | ||
2726 | |||
2727 | watchdog timers [HW,WDT] For information on watchdog timers, | 2644 | watchdog timers [HW,WDT] For information on watchdog timers, |
2728 | see Documentation/watchdog/watchdog-parameters.txt | 2645 | see Documentation/watchdog/watchdog-parameters.txt |
2729 | or other driver-specific files in the | 2646 | or other driver-specific files in the |
@@ -2749,8 +2666,10 @@ and is between 256 and 4096 characters. It is defined in the file | |||
2749 | aux-ide-disks -- unplug non-primary-master IDE devices | 2666 | aux-ide-disks -- unplug non-primary-master IDE devices |
2750 | nics -- unplug network devices | 2667 | nics -- unplug network devices |
2751 | all -- unplug all emulated devices (NICs and IDE disks) | 2668 | all -- unplug all emulated devices (NICs and IDE disks) |
2752 | ignore -- continue loading the Xen platform PCI driver even | 2669 | unnecessary -- unplugging emulated devices is |
2753 | if the version check failed | 2670 | unnecessary even if the host did not respond to |
2671 | the unplug protocol | ||
2672 | never -- do not unplug even if version check succeeds | ||
2754 | 2673 | ||
2755 | xirc2ps_cs= [NET,PCMCIA] | 2674 | xirc2ps_cs= [NET,PCMCIA] |
2756 | Format: | 2675 | Format: |
diff --git a/Documentation/kprobes.txt b/Documentation/kprobes.txt index 1762b81fcdf2..741fe66d6eca 100644 --- a/Documentation/kprobes.txt +++ b/Documentation/kprobes.txt | |||
@@ -542,9 +542,11 @@ Kprobes does not use mutexes or allocate memory except during | |||
542 | registration and unregistration. | 542 | registration and unregistration. |
543 | 543 | ||
544 | Probe handlers are run with preemption disabled. Depending on the | 544 | Probe handlers are run with preemption disabled. Depending on the |
545 | architecture, handlers may also run with interrupts disabled. In any | 545 | architecture and optimization state, handlers may also run with |
546 | case, your handler should not yield the CPU (e.g., by attempting to | 546 | interrupts disabled (e.g., kretprobe handlers and optimized kprobe |
547 | acquire a semaphore). | 547 | handlers run without interrupt disabled on x86/x86-64). In any case, |
548 | your handler should not yield the CPU (e.g., by attempting to acquire | ||
549 | a semaphore). | ||
548 | 550 | ||
549 | Since a return probe is implemented by replacing the return | 551 | Since a return probe is implemented by replacing the return |
550 | address with the trampoline's address, stack backtraces and calls | 552 | address with the trampoline's address, stack backtraces and calls |
diff --git a/Documentation/kvm/api.txt b/Documentation/kvm/api.txt index 5f5b64982b1a..b336266bea5e 100644 --- a/Documentation/kvm/api.txt +++ b/Documentation/kvm/api.txt | |||
@@ -320,13 +320,13 @@ struct kvm_translation { | |||
320 | 4.15 KVM_INTERRUPT | 320 | 4.15 KVM_INTERRUPT |
321 | 321 | ||
322 | Capability: basic | 322 | Capability: basic |
323 | Architectures: x86 | 323 | Architectures: x86, ppc |
324 | Type: vcpu ioctl | 324 | Type: vcpu ioctl |
325 | Parameters: struct kvm_interrupt (in) | 325 | Parameters: struct kvm_interrupt (in) |
326 | Returns: 0 on success, -1 on error | 326 | Returns: 0 on success, -1 on error |
327 | 327 | ||
328 | Queues a hardware interrupt vector to be injected. This is only | 328 | Queues a hardware interrupt vector to be injected. This is only |
329 | useful if in-kernel local APIC is not used. | 329 | useful if in-kernel local APIC or equivalent is not used. |
330 | 330 | ||
331 | /* for KVM_INTERRUPT */ | 331 | /* for KVM_INTERRUPT */ |
332 | struct kvm_interrupt { | 332 | struct kvm_interrupt { |
@@ -334,8 +334,37 @@ struct kvm_interrupt { | |||
334 | __u32 irq; | 334 | __u32 irq; |
335 | }; | 335 | }; |
336 | 336 | ||
337 | X86: | ||
338 | |||
337 | Note 'irq' is an interrupt vector, not an interrupt pin or line. | 339 | Note 'irq' is an interrupt vector, not an interrupt pin or line. |
338 | 340 | ||
341 | PPC: | ||
342 | |||
343 | Queues an external interrupt to be injected. This ioctl is overleaded | ||
344 | with 3 different irq values: | ||
345 | |||
346 | a) KVM_INTERRUPT_SET | ||
347 | |||
348 | This injects an edge type external interrupt into the guest once it's ready | ||
349 | to receive interrupts. When injected, the interrupt is done. | ||
350 | |||
351 | b) KVM_INTERRUPT_UNSET | ||
352 | |||
353 | This unsets any pending interrupt. | ||
354 | |||
355 | Only available with KVM_CAP_PPC_UNSET_IRQ. | ||
356 | |||
357 | c) KVM_INTERRUPT_SET_LEVEL | ||
358 | |||
359 | This injects a level type external interrupt into the guest context. The | ||
360 | interrupt stays pending until a specific ioctl with KVM_INTERRUPT_UNSET | ||
361 | is triggered. | ||
362 | |||
363 | Only available with KVM_CAP_PPC_IRQ_LEVEL. | ||
364 | |||
365 | Note that any value for 'irq' other than the ones stated above is invalid | ||
366 | and incurs unexpected behavior. | ||
367 | |||
339 | 4.16 KVM_DEBUG_GUEST | 368 | 4.16 KVM_DEBUG_GUEST |
340 | 369 | ||
341 | Capability: basic | 370 | Capability: basic |
@@ -1013,8 +1042,9 @@ number is just right, the 'nent' field is adjusted to the number of valid | |||
1013 | entries in the 'entries' array, which is then filled. | 1042 | entries in the 'entries' array, which is then filled. |
1014 | 1043 | ||
1015 | The entries returned are the host cpuid as returned by the cpuid instruction, | 1044 | The entries returned are the host cpuid as returned by the cpuid instruction, |
1016 | with unknown or unsupported features masked out. The fields in each entry | 1045 | with unknown or unsupported features masked out. Some features (for example, |
1017 | are defined as follows: | 1046 | x2apic), may not be present in the host cpu, but are exposed by kvm if it can |
1047 | emulate them efficiently. The fields in each entry are defined as follows: | ||
1018 | 1048 | ||
1019 | function: the eax value used to obtain the entry | 1049 | function: the eax value used to obtain the entry |
1020 | index: the ecx value used to obtain the entry (for entries that are | 1050 | index: the ecx value used to obtain the entry (for entries that are |
@@ -1032,6 +1062,29 @@ are defined as follows: | |||
1032 | eax, ebx, ecx, edx: the values returned by the cpuid instruction for | 1062 | eax, ebx, ecx, edx: the values returned by the cpuid instruction for |
1033 | this function/index combination | 1063 | this function/index combination |
1034 | 1064 | ||
1065 | 4.46 KVM_PPC_GET_PVINFO | ||
1066 | |||
1067 | Capability: KVM_CAP_PPC_GET_PVINFO | ||
1068 | Architectures: ppc | ||
1069 | Type: vm ioctl | ||
1070 | Parameters: struct kvm_ppc_pvinfo (out) | ||
1071 | Returns: 0 on success, !0 on error | ||
1072 | |||
1073 | struct kvm_ppc_pvinfo { | ||
1074 | __u32 flags; | ||
1075 | __u32 hcall[4]; | ||
1076 | __u8 pad[108]; | ||
1077 | }; | ||
1078 | |||
1079 | This ioctl fetches PV specific information that need to be passed to the guest | ||
1080 | using the device tree or other means from vm context. | ||
1081 | |||
1082 | For now the only implemented piece of information distributed here is an array | ||
1083 | of 4 instructions that make up a hypercall. | ||
1084 | |||
1085 | If any additional field gets added to this structure later on, a bit for that | ||
1086 | additional piece of information will be set in the flags bitmap. | ||
1087 | |||
1035 | 5. The kvm_run structure | 1088 | 5. The kvm_run structure |
1036 | 1089 | ||
1037 | Application code obtains a pointer to the kvm_run structure by | 1090 | Application code obtains a pointer to the kvm_run structure by |
diff --git a/Documentation/kvm/ppc-pv.txt b/Documentation/kvm/ppc-pv.txt new file mode 100644 index 000000000000..a7f2244b3be9 --- /dev/null +++ b/Documentation/kvm/ppc-pv.txt | |||
@@ -0,0 +1,196 @@ | |||
1 | The PPC KVM paravirtual interface | ||
2 | ================================= | ||
3 | |||
4 | The basic execution principle by which KVM on PowerPC works is to run all kernel | ||
5 | space code in PR=1 which is user space. This way we trap all privileged | ||
6 | instructions and can emulate them accordingly. | ||
7 | |||
8 | Unfortunately that is also the downfall. There are quite some privileged | ||
9 | instructions that needlessly return us to the hypervisor even though they | ||
10 | could be handled differently. | ||
11 | |||
12 | This is what the PPC PV interface helps with. It takes privileged instructions | ||
13 | and transforms them into unprivileged ones with some help from the hypervisor. | ||
14 | This cuts down virtualization costs by about 50% on some of my benchmarks. | ||
15 | |||
16 | The code for that interface can be found in arch/powerpc/kernel/kvm* | ||
17 | |||
18 | Querying for existence | ||
19 | ====================== | ||
20 | |||
21 | To find out if we're running on KVM or not, we leverage the device tree. When | ||
22 | Linux is running on KVM, a node /hypervisor exists. That node contains a | ||
23 | compatible property with the value "linux,kvm". | ||
24 | |||
25 | Once you determined you're running under a PV capable KVM, you can now use | ||
26 | hypercalls as described below. | ||
27 | |||
28 | KVM hypercalls | ||
29 | ============== | ||
30 | |||
31 | Inside the device tree's /hypervisor node there's a property called | ||
32 | 'hypercall-instructions'. This property contains at most 4 opcodes that make | ||
33 | up the hypercall. To call a hypercall, just call these instructions. | ||
34 | |||
35 | The parameters are as follows: | ||
36 | |||
37 | Register IN OUT | ||
38 | |||
39 | r0 - volatile | ||
40 | r3 1st parameter Return code | ||
41 | r4 2nd parameter 1st output value | ||
42 | r5 3rd parameter 2nd output value | ||
43 | r6 4th parameter 3rd output value | ||
44 | r7 5th parameter 4th output value | ||
45 | r8 6th parameter 5th output value | ||
46 | r9 7th parameter 6th output value | ||
47 | r10 8th parameter 7th output value | ||
48 | r11 hypercall number 8th output value | ||
49 | r12 - volatile | ||
50 | |||
51 | Hypercall definitions are shared in generic code, so the same hypercall numbers | ||
52 | apply for x86 and powerpc alike with the exception that each KVM hypercall | ||
53 | also needs to be ORed with the KVM vendor code which is (42 << 16). | ||
54 | |||
55 | Return codes can be as follows: | ||
56 | |||
57 | Code Meaning | ||
58 | |||
59 | 0 Success | ||
60 | 12 Hypercall not implemented | ||
61 | <0 Error | ||
62 | |||
63 | The magic page | ||
64 | ============== | ||
65 | |||
66 | To enable communication between the hypervisor and guest there is a new shared | ||
67 | page that contains parts of supervisor visible register state. The guest can | ||
68 | map this shared page using the KVM hypercall KVM_HC_PPC_MAP_MAGIC_PAGE. | ||
69 | |||
70 | With this hypercall issued the guest always gets the magic page mapped at the | ||
71 | desired location in effective and physical address space. For now, we always | ||
72 | map the page to -4096. This way we can access it using absolute load and store | ||
73 | functions. The following instruction reads the first field of the magic page: | ||
74 | |||
75 | ld rX, -4096(0) | ||
76 | |||
77 | The interface is designed to be extensible should there be need later to add | ||
78 | additional registers to the magic page. If you add fields to the magic page, | ||
79 | also define a new hypercall feature to indicate that the host can give you more | ||
80 | registers. Only if the host supports the additional features, make use of them. | ||
81 | |||
82 | The magic page has the following layout as described in | ||
83 | arch/powerpc/include/asm/kvm_para.h: | ||
84 | |||
85 | struct kvm_vcpu_arch_shared { | ||
86 | __u64 scratch1; | ||
87 | __u64 scratch2; | ||
88 | __u64 scratch3; | ||
89 | __u64 critical; /* Guest may not get interrupts if == r1 */ | ||
90 | __u64 sprg0; | ||
91 | __u64 sprg1; | ||
92 | __u64 sprg2; | ||
93 | __u64 sprg3; | ||
94 | __u64 srr0; | ||
95 | __u64 srr1; | ||
96 | __u64 dar; | ||
97 | __u64 msr; | ||
98 | __u32 dsisr; | ||
99 | __u32 int_pending; /* Tells the guest if we have an interrupt */ | ||
100 | }; | ||
101 | |||
102 | Additions to the page must only occur at the end. Struct fields are always 32 | ||
103 | or 64 bit aligned, depending on them being 32 or 64 bit wide respectively. | ||
104 | |||
105 | Magic page features | ||
106 | =================== | ||
107 | |||
108 | When mapping the magic page using the KVM hypercall KVM_HC_PPC_MAP_MAGIC_PAGE, | ||
109 | a second return value is passed to the guest. This second return value contains | ||
110 | a bitmap of available features inside the magic page. | ||
111 | |||
112 | The following enhancements to the magic page are currently available: | ||
113 | |||
114 | KVM_MAGIC_FEAT_SR Maps SR registers r/w in the magic page | ||
115 | |||
116 | For enhanced features in the magic page, please check for the existence of the | ||
117 | feature before using them! | ||
118 | |||
119 | MSR bits | ||
120 | ======== | ||
121 | |||
122 | The MSR contains bits that require hypervisor intervention and bits that do | ||
123 | not require direct hypervisor intervention because they only get interpreted | ||
124 | when entering the guest or don't have any impact on the hypervisor's behavior. | ||
125 | |||
126 | The following bits are safe to be set inside the guest: | ||
127 | |||
128 | MSR_EE | ||
129 | MSR_RI | ||
130 | MSR_CR | ||
131 | MSR_ME | ||
132 | |||
133 | If any other bit changes in the MSR, please still use mtmsr(d). | ||
134 | |||
135 | Patched instructions | ||
136 | ==================== | ||
137 | |||
138 | The "ld" and "std" instructions are transormed to "lwz" and "stw" instructions | ||
139 | respectively on 32 bit systems with an added offset of 4 to accomodate for big | ||
140 | endianness. | ||
141 | |||
142 | The following is a list of mapping the Linux kernel performs when running as | ||
143 | guest. Implementing any of those mappings is optional, as the instruction traps | ||
144 | also act on the shared page. So calling privileged instructions still works as | ||
145 | before. | ||
146 | |||
147 | From To | ||
148 | ==== == | ||
149 | |||
150 | mfmsr rX ld rX, magic_page->msr | ||
151 | mfsprg rX, 0 ld rX, magic_page->sprg0 | ||
152 | mfsprg rX, 1 ld rX, magic_page->sprg1 | ||
153 | mfsprg rX, 2 ld rX, magic_page->sprg2 | ||
154 | mfsprg rX, 3 ld rX, magic_page->sprg3 | ||
155 | mfsrr0 rX ld rX, magic_page->srr0 | ||
156 | mfsrr1 rX ld rX, magic_page->srr1 | ||
157 | mfdar rX ld rX, magic_page->dar | ||
158 | mfdsisr rX lwz rX, magic_page->dsisr | ||
159 | |||
160 | mtmsr rX std rX, magic_page->msr | ||
161 | mtsprg 0, rX std rX, magic_page->sprg0 | ||
162 | mtsprg 1, rX std rX, magic_page->sprg1 | ||
163 | mtsprg 2, rX std rX, magic_page->sprg2 | ||
164 | mtsprg 3, rX std rX, magic_page->sprg3 | ||
165 | mtsrr0 rX std rX, magic_page->srr0 | ||
166 | mtsrr1 rX std rX, magic_page->srr1 | ||
167 | mtdar rX std rX, magic_page->dar | ||
168 | mtdsisr rX stw rX, magic_page->dsisr | ||
169 | |||
170 | tlbsync nop | ||
171 | |||
172 | mtmsrd rX, 0 b <special mtmsr section> | ||
173 | mtmsr rX b <special mtmsr section> | ||
174 | |||
175 | mtmsrd rX, 1 b <special mtmsrd section> | ||
176 | |||
177 | [Book3S only] | ||
178 | mtsrin rX, rY b <special mtsrin section> | ||
179 | |||
180 | [BookE only] | ||
181 | wrteei [0|1] b <special wrteei section> | ||
182 | |||
183 | |||
184 | Some instructions require more logic to determine what's going on than a load | ||
185 | or store instruction can deliver. To enable patching of those, we keep some | ||
186 | RAM around where we can live translate instructions to. What happens is the | ||
187 | following: | ||
188 | |||
189 | 1) copy emulation code to memory | ||
190 | 2) patch that code to fit the emulated instruction | ||
191 | 3) patch that code to return to the original pc + 4 | ||
192 | 4) patch the original instruction to branch to the new code | ||
193 | |||
194 | That way we can inject an arbitrary amount of code as replacement for a single | ||
195 | instruction. This allows us to check for pending interrupts when setting EE=1 | ||
196 | for example. | ||
diff --git a/Documentation/kvm/timekeeping.txt b/Documentation/kvm/timekeeping.txt new file mode 100644 index 000000000000..0c5033a58c9e --- /dev/null +++ b/Documentation/kvm/timekeeping.txt | |||
@@ -0,0 +1,612 @@ | |||
1 | |||
2 | Timekeeping Virtualization for X86-Based Architectures | ||
3 | |||
4 | Zachary Amsden <zamsden@redhat.com> | ||
5 | Copyright (c) 2010, Red Hat. All rights reserved. | ||
6 | |||
7 | 1) Overview | ||
8 | 2) Timing Devices | ||
9 | 3) TSC Hardware | ||
10 | 4) Virtualization Problems | ||
11 | |||
12 | ========================================================================= | ||
13 | |||
14 | 1) Overview | ||
15 | |||
16 | One of the most complicated parts of the X86 platform, and specifically, | ||
17 | the virtualization of this platform is the plethora of timing devices available | ||
18 | and the complexity of emulating those devices. In addition, virtualization of | ||
19 | time introduces a new set of challenges because it introduces a multiplexed | ||
20 | division of time beyond the control of the guest CPU. | ||
21 | |||
22 | First, we will describe the various timekeeping hardware available, then | ||
23 | present some of the problems which arise and solutions available, giving | ||
24 | specific recommendations for certain classes of KVM guests. | ||
25 | |||
26 | The purpose of this document is to collect data and information relevant to | ||
27 | timekeeping which may be difficult to find elsewhere, specifically, | ||
28 | information relevant to KVM and hardware-based virtualization. | ||
29 | |||
30 | ========================================================================= | ||
31 | |||
32 | 2) Timing Devices | ||
33 | |||
34 | First we discuss the basic hardware devices available. TSC and the related | ||
35 | KVM clock are special enough to warrant a full exposition and are described in | ||
36 | the following section. | ||
37 | |||
38 | 2.1) i8254 - PIT | ||
39 | |||
40 | One of the first timer devices available is the programmable interrupt timer, | ||
41 | or PIT. The PIT has a fixed frequency 1.193182 MHz base clock and three | ||
42 | channels which can be programmed to deliver periodic or one-shot interrupts. | ||
43 | These three channels can be configured in different modes and have individual | ||
44 | counters. Channel 1 and 2 were not available for general use in the original | ||
45 | IBM PC, and historically were connected to control RAM refresh and the PC | ||
46 | speaker. Now the PIT is typically integrated as part of an emulated chipset | ||
47 | and a separate physical PIT is not used. | ||
48 | |||
49 | The PIT uses I/O ports 0x40 - 0x43. Access to the 16-bit counters is done | ||
50 | using single or multiple byte access to the I/O ports. There are 6 modes | ||
51 | available, but not all modes are available to all timers, as only timer 2 | ||
52 | has a connected gate input, required for modes 1 and 5. The gate line is | ||
53 | controlled by port 61h, bit 0, as illustrated in the following diagram. | ||
54 | |||
55 | -------------- ---------------- | ||
56 | | | | | | ||
57 | | 1.1932 MHz |---------->| CLOCK OUT | ---------> IRQ 0 | ||
58 | | Clock | | | | | ||
59 | -------------- | +->| GATE TIMER 0 | | ||
60 | | ---------------- | ||
61 | | | ||
62 | | ---------------- | ||
63 | | | | | ||
64 | |------>| CLOCK OUT | ---------> 66.3 KHZ DRAM | ||
65 | | | | (aka /dev/null) | ||
66 | | +->| GATE TIMER 1 | | ||
67 | | ---------------- | ||
68 | | | ||
69 | | ---------------- | ||
70 | | | | | ||
71 | |------>| CLOCK OUT | ---------> Port 61h, bit 5 | ||
72 | | | | | ||
73 | Port 61h, bit 0 ---------->| GATE TIMER 2 | \_.---- ____ | ||
74 | ---------------- _| )--|LPF|---Speaker | ||
75 | / *---- \___/ | ||
76 | Port 61h, bit 1 -----------------------------------/ | ||
77 | |||
78 | The timer modes are now described. | ||
79 | |||
80 | Mode 0: Single Timeout. This is a one-shot software timeout that counts down | ||
81 | when the gate is high (always true for timers 0 and 1). When the count | ||
82 | reaches zero, the output goes high. | ||
83 | |||
84 | Mode 1: Triggered One-shot. The output is intially set high. When the gate | ||
85 | line is set high, a countdown is initiated (which does not stop if the gate is | ||
86 | lowered), during which the output is set low. When the count reaches zero, | ||
87 | the output goes high. | ||
88 | |||
89 | Mode 2: Rate Generator. The output is initially set high. When the countdown | ||
90 | reaches 1, the output goes low for one count and then returns high. The value | ||
91 | is reloaded and the countdown automatically resumes. If the gate line goes | ||
92 | low, the count is halted. If the output is low when the gate is lowered, the | ||
93 | output automatically goes high (this only affects timer 2). | ||
94 | |||
95 | Mode 3: Square Wave. This generates a high / low square wave. The count | ||
96 | determines the length of the pulse, which alternates between high and low | ||
97 | when zero is reached. The count only proceeds when gate is high and is | ||
98 | automatically reloaded on reaching zero. The count is decremented twice at | ||
99 | each clock to generate a full high / low cycle at the full periodic rate. | ||
100 | If the count is even, the clock remains high for N/2 counts and low for N/2 | ||
101 | counts; if the clock is odd, the clock is high for (N+1)/2 counts and low | ||
102 | for (N-1)/2 counts. Only even values are latched by the counter, so odd | ||
103 | values are not observed when reading. This is the intended mode for timer 2, | ||
104 | which generates sine-like tones by low-pass filtering the square wave output. | ||
105 | |||
106 | Mode 4: Software Strobe. After programming this mode and loading the counter, | ||
107 | the output remains high until the counter reaches zero. Then the output | ||
108 | goes low for 1 clock cycle and returns high. The counter is not reloaded. | ||
109 | Counting only occurs when gate is high. | ||
110 | |||
111 | Mode 5: Hardware Strobe. After programming and loading the counter, the | ||
112 | output remains high. When the gate is raised, a countdown is initiated | ||
113 | (which does not stop if the gate is lowered). When the counter reaches zero, | ||
114 | the output goes low for 1 clock cycle and then returns high. The counter is | ||
115 | not reloaded. | ||
116 | |||
117 | In addition to normal binary counting, the PIT supports BCD counting. The | ||
118 | command port, 0x43 is used to set the counter and mode for each of the three | ||
119 | timers. | ||
120 | |||
121 | PIT commands, issued to port 0x43, using the following bit encoding: | ||
122 | |||
123 | Bit 7-4: Command (See table below) | ||
124 | Bit 3-1: Mode (000 = Mode 0, 101 = Mode 5, 11X = undefined) | ||
125 | Bit 0 : Binary (0) / BCD (1) | ||
126 | |||
127 | Command table: | ||
128 | |||
129 | 0000 - Latch Timer 0 count for port 0x40 | ||
130 | sample and hold the count to be read in port 0x40; | ||
131 | additional commands ignored until counter is read; | ||
132 | mode bits ignored. | ||
133 | |||
134 | 0001 - Set Timer 0 LSB mode for port 0x40 | ||
135 | set timer to read LSB only and force MSB to zero; | ||
136 | mode bits set timer mode | ||
137 | |||
138 | 0010 - Set Timer 0 MSB mode for port 0x40 | ||
139 | set timer to read MSB only and force LSB to zero; | ||
140 | mode bits set timer mode | ||
141 | |||
142 | 0011 - Set Timer 0 16-bit mode for port 0x40 | ||
143 | set timer to read / write LSB first, then MSB; | ||
144 | mode bits set timer mode | ||
145 | |||
146 | 0100 - Latch Timer 1 count for port 0x41 - as described above | ||
147 | 0101 - Set Timer 1 LSB mode for port 0x41 - as described above | ||
148 | 0110 - Set Timer 1 MSB mode for port 0x41 - as described above | ||
149 | 0111 - Set Timer 1 16-bit mode for port 0x41 - as described above | ||
150 | |||
151 | 1000 - Latch Timer 2 count for port 0x42 - as described above | ||
152 | 1001 - Set Timer 2 LSB mode for port 0x42 - as described above | ||
153 | 1010 - Set Timer 2 MSB mode for port 0x42 - as described above | ||
154 | 1011 - Set Timer 2 16-bit mode for port 0x42 as described above | ||
155 | |||
156 | 1101 - General counter latch | ||
157 | Latch combination of counters into corresponding ports | ||
158 | Bit 3 = Counter 2 | ||
159 | Bit 2 = Counter 1 | ||
160 | Bit 1 = Counter 0 | ||
161 | Bit 0 = Unused | ||
162 | |||
163 | 1110 - Latch timer status | ||
164 | Latch combination of counter mode into corresponding ports | ||
165 | Bit 3 = Counter 2 | ||
166 | Bit 2 = Counter 1 | ||
167 | Bit 1 = Counter 0 | ||
168 | |||
169 | The output of ports 0x40-0x42 following this command will be: | ||
170 | |||
171 | Bit 7 = Output pin | ||
172 | Bit 6 = Count loaded (0 if timer has expired) | ||
173 | Bit 5-4 = Read / Write mode | ||
174 | 01 = MSB only | ||
175 | 10 = LSB only | ||
176 | 11 = LSB / MSB (16-bit) | ||
177 | Bit 3-1 = Mode | ||
178 | Bit 0 = Binary (0) / BCD mode (1) | ||
179 | |||
180 | 2.2) RTC | ||
181 | |||
182 | The second device which was available in the original PC was the MC146818 real | ||
183 | time clock. The original device is now obsolete, and usually emulated by the | ||
184 | system chipset, sometimes by an HPET and some frankenstein IRQ routing. | ||
185 | |||
186 | The RTC is accessed through CMOS variables, which uses an index register to | ||
187 | control which bytes are read. Since there is only one index register, read | ||
188 | of the CMOS and read of the RTC require lock protection (in addition, it is | ||
189 | dangerous to allow userspace utilities such as hwclock to have direct RTC | ||
190 | access, as they could corrupt kernel reads and writes of CMOS memory). | ||
191 | |||
192 | The RTC generates an interrupt which is usually routed to IRQ 8. The interrupt | ||
193 | can function as a periodic timer, an additional once a day alarm, and can issue | ||
194 | interrupts after an update of the CMOS registers by the MC146818 is complete. | ||
195 | The type of interrupt is signalled in the RTC status registers. | ||
196 | |||
197 | The RTC will update the current time fields by battery power even while the | ||
198 | system is off. The current time fields should not be read while an update is | ||
199 | in progress, as indicated in the status register. | ||
200 | |||
201 | The clock uses a 32.768kHz crystal, so bits 6-4 of register A should be | ||
202 | programmed to a 32kHz divider if the RTC is to count seconds. | ||
203 | |||
204 | This is the RAM map originally used for the RTC/CMOS: | ||
205 | |||
206 | Location Size Description | ||
207 | ------------------------------------------ | ||
208 | 00h byte Current second (BCD) | ||
209 | 01h byte Seconds alarm (BCD) | ||
210 | 02h byte Current minute (BCD) | ||
211 | 03h byte Minutes alarm (BCD) | ||
212 | 04h byte Current hour (BCD) | ||
213 | 05h byte Hours alarm (BCD) | ||
214 | 06h byte Current day of week (BCD) | ||
215 | 07h byte Current day of month (BCD) | ||
216 | 08h byte Current month (BCD) | ||
217 | 09h byte Current year (BCD) | ||
218 | 0Ah byte Register A | ||
219 | bit 7 = Update in progress | ||
220 | bit 6-4 = Divider for clock | ||
221 | 000 = 4.194 MHz | ||
222 | 001 = 1.049 MHz | ||
223 | 010 = 32 kHz | ||
224 | 10X = test modes | ||
225 | 110 = reset / disable | ||
226 | 111 = reset / disable | ||
227 | bit 3-0 = Rate selection for periodic interrupt | ||
228 | 000 = periodic timer disabled | ||
229 | 001 = 3.90625 uS | ||
230 | 010 = 7.8125 uS | ||
231 | 011 = .122070 mS | ||
232 | 100 = .244141 mS | ||
233 | ... | ||
234 | 1101 = 125 mS | ||
235 | 1110 = 250 mS | ||
236 | 1111 = 500 mS | ||
237 | 0Bh byte Register B | ||
238 | bit 7 = Run (0) / Halt (1) | ||
239 | bit 6 = Periodic interrupt enable | ||
240 | bit 5 = Alarm interrupt enable | ||
241 | bit 4 = Update-ended interrupt enable | ||
242 | bit 3 = Square wave interrupt enable | ||
243 | bit 2 = BCD calendar (0) / Binary (1) | ||
244 | bit 1 = 12-hour mode (0) / 24-hour mode (1) | ||
245 | bit 0 = 0 (DST off) / 1 (DST enabled) | ||
246 | OCh byte Register C (read only) | ||
247 | bit 7 = interrupt request flag (IRQF) | ||
248 | bit 6 = periodic interrupt flag (PF) | ||
249 | bit 5 = alarm interrupt flag (AF) | ||
250 | bit 4 = update interrupt flag (UF) | ||
251 | bit 3-0 = reserved | ||
252 | ODh byte Register D (read only) | ||
253 | bit 7 = RTC has power | ||
254 | bit 6-0 = reserved | ||
255 | 32h byte Current century BCD (*) | ||
256 | (*) location vendor specific and now determined from ACPI global tables | ||
257 | |||
258 | 2.3) APIC | ||
259 | |||
260 | On Pentium and later processors, an on-board timer is available to each CPU | ||
261 | as part of the Advanced Programmable Interrupt Controller. The APIC is | ||
262 | accessed through memory-mapped registers and provides interrupt service to each | ||
263 | CPU, used for IPIs and local timer interrupts. | ||
264 | |||
265 | Although in theory the APIC is a safe and stable source for local interrupts, | ||
266 | in practice, many bugs and glitches have occurred due to the special nature of | ||
267 | the APIC CPU-local memory-mapped hardware. Beware that CPU errata may affect | ||
268 | the use of the APIC and that workarounds may be required. In addition, some of | ||
269 | these workarounds pose unique constraints for virtualization - requiring either | ||
270 | extra overhead incurred from extra reads of memory-mapped I/O or additional | ||
271 | functionality that may be more computationally expensive to implement. | ||
272 | |||
273 | Since the APIC is documented quite well in the Intel and AMD manuals, we will | ||
274 | avoid repetition of the detail here. It should be pointed out that the APIC | ||
275 | timer is programmed through the LVT (local vector timer) register, is capable | ||
276 | of one-shot or periodic operation, and is based on the bus clock divided down | ||
277 | by the programmable divider register. | ||
278 | |||
279 | 2.4) HPET | ||
280 | |||
281 | HPET is quite complex, and was originally intended to replace the PIT / RTC | ||
282 | support of the X86 PC. It remains to be seen whether that will be the case, as | ||
283 | the de facto standard of PC hardware is to emulate these older devices. Some | ||
284 | systems designated as legacy free may support only the HPET as a hardware timer | ||
285 | device. | ||
286 | |||
287 | The HPET spec is rather loose and vague, requiring at least 3 hardware timers, | ||
288 | but allowing implementation freedom to support many more. It also imposes no | ||
289 | fixed rate on the timer frequency, but does impose some extremal values on | ||
290 | frequency, error and slew. | ||
291 | |||
292 | In general, the HPET is recommended as a high precision (compared to PIT /RTC) | ||
293 | time source which is independent of local variation (as there is only one HPET | ||
294 | in any given system). The HPET is also memory-mapped, and its presence is | ||
295 | indicated through ACPI tables by the BIOS. | ||
296 | |||
297 | Detailed specification of the HPET is beyond the current scope of this | ||
298 | document, as it is also very well documented elsewhere. | ||
299 | |||
300 | 2.5) Offboard Timers | ||
301 | |||
302 | Several cards, both proprietary (watchdog boards) and commonplace (e1000) have | ||
303 | timing chips built into the cards which may have registers which are accessible | ||
304 | to kernel or user drivers. To the author's knowledge, using these to generate | ||
305 | a clocksource for a Linux or other kernel has not yet been attempted and is in | ||
306 | general frowned upon as not playing by the agreed rules of the game. Such a | ||
307 | timer device would require additional support to be virtualized properly and is | ||
308 | not considered important at this time as no known operating system does this. | ||
309 | |||
310 | ========================================================================= | ||
311 | |||
312 | 3) TSC Hardware | ||
313 | |||
314 | The TSC or time stamp counter is relatively simple in theory; it counts | ||
315 | instruction cycles issued by the processor, which can be used as a measure of | ||
316 | time. In practice, due to a number of problems, it is the most complicated | ||
317 | timekeeping device to use. | ||
318 | |||
319 | The TSC is represented internally as a 64-bit MSR which can be read with the | ||
320 | RDMSR, RDTSC, or RDTSCP (when available) instructions. In the past, hardware | ||
321 | limitations made it possible to write the TSC, but generally on old hardware it | ||
322 | was only possible to write the low 32-bits of the 64-bit counter, and the upper | ||
323 | 32-bits of the counter were cleared. Now, however, on Intel processors family | ||
324 | 0Fh, for models 3, 4 and 6, and family 06h, models e and f, this restriction | ||
325 | has been lifted and all 64-bits are writable. On AMD systems, the ability to | ||
326 | write the TSC MSR is not an architectural guarantee. | ||
327 | |||
328 | The TSC is accessible from CPL-0 and conditionally, for CPL > 0 software by | ||
329 | means of the CR4.TSD bit, which when enabled, disables CPL > 0 TSC access. | ||
330 | |||
331 | Some vendors have implemented an additional instruction, RDTSCP, which returns | ||
332 | atomically not just the TSC, but an indicator which corresponds to the | ||
333 | processor number. This can be used to index into an array of TSC variables to | ||
334 | determine offset information in SMP systems where TSCs are not synchronized. | ||
335 | The presence of this instruction must be determined by consulting CPUID feature | ||
336 | bits. | ||
337 | |||
338 | Both VMX and SVM provide extension fields in the virtualization hardware which | ||
339 | allows the guest visible TSC to be offset by a constant. Newer implementations | ||
340 | promise to allow the TSC to additionally be scaled, but this hardware is not | ||
341 | yet widely available. | ||
342 | |||
343 | 3.1) TSC synchronization | ||
344 | |||
345 | The TSC is a CPU-local clock in most implementations. This means, on SMP | ||
346 | platforms, the TSCs of different CPUs may start at different times depending | ||
347 | on when the CPUs are powered on. Generally, CPUs on the same die will share | ||
348 | the same clock, however, this is not always the case. | ||
349 | |||
350 | The BIOS may attempt to resynchronize the TSCs during the poweron process and | ||
351 | the operating system or other system software may attempt to do this as well. | ||
352 | Several hardware limitations make the problem worse - if it is not possible to | ||
353 | write the full 64-bits of the TSC, it may be impossible to match the TSC in | ||
354 | newly arriving CPUs to that of the rest of the system, resulting in | ||
355 | unsynchronized TSCs. This may be done by BIOS or system software, but in | ||
356 | practice, getting a perfectly synchronized TSC will not be possible unless all | ||
357 | values are read from the same clock, which generally only is possible on single | ||
358 | socket systems or those with special hardware support. | ||
359 | |||
360 | 3.2) TSC and CPU hotplug | ||
361 | |||
362 | As touched on already, CPUs which arrive later than the boot time of the system | ||
363 | may not have a TSC value that is synchronized with the rest of the system. | ||
364 | Either system software, BIOS, or SMM code may actually try to establish the TSC | ||
365 | to a value matching the rest of the system, but a perfect match is usually not | ||
366 | a guarantee. This can have the effect of bringing a system from a state where | ||
367 | TSC is synchronized back to a state where TSC synchronization flaws, however | ||
368 | small, may be exposed to the OS and any virtualization environment. | ||
369 | |||
370 | 3.3) TSC and multi-socket / NUMA | ||
371 | |||
372 | Multi-socket systems, especially large multi-socket systems are likely to have | ||
373 | individual clocksources rather than a single, universally distributed clock. | ||
374 | Since these clocks are driven by different crystals, they will not have | ||
375 | perfectly matched frequency, and temperature and electrical variations will | ||
376 | cause the CPU clocks, and thus the TSCs to drift over time. Depending on the | ||
377 | exact clock and bus design, the drift may or may not be fixed in absolute | ||
378 | error, and may accumulate over time. | ||
379 | |||
380 | In addition, very large systems may deliberately slew the clocks of individual | ||
381 | cores. This technique, known as spread-spectrum clocking, reduces EMI at the | ||
382 | clock frequency and harmonics of it, which may be required to pass FCC | ||
383 | standards for telecommunications and computer equipment. | ||
384 | |||
385 | It is recommended not to trust the TSCs to remain synchronized on NUMA or | ||
386 | multiple socket systems for these reasons. | ||
387 | |||
388 | 3.4) TSC and C-states | ||
389 | |||
390 | C-states, or idling states of the processor, especially C1E and deeper sleep | ||
391 | states may be problematic for TSC as well. The TSC may stop advancing in such | ||
392 | a state, resulting in a TSC which is behind that of other CPUs when execution | ||
393 | is resumed. Such CPUs must be detected and flagged by the operating system | ||
394 | based on CPU and chipset identifications. | ||
395 | |||
396 | The TSC in such a case may be corrected by catching it up to a known external | ||
397 | clocksource. | ||
398 | |||
399 | 3.5) TSC frequency change / P-states | ||
400 | |||
401 | To make things slightly more interesting, some CPUs may change frequency. They | ||
402 | may or may not run the TSC at the same rate, and because the frequency change | ||
403 | may be staggered or slewed, at some points in time, the TSC rate may not be | ||
404 | known other than falling within a range of values. In this case, the TSC will | ||
405 | not be a stable time source, and must be calibrated against a known, stable, | ||
406 | external clock to be a usable source of time. | ||
407 | |||
408 | Whether the TSC runs at a constant rate or scales with the P-state is model | ||
409 | dependent and must be determined by inspecting CPUID, chipset or vendor | ||
410 | specific MSR fields. | ||
411 | |||
412 | In addition, some vendors have known bugs where the P-state is actually | ||
413 | compensated for properly during normal operation, but when the processor is | ||
414 | inactive, the P-state may be raised temporarily to service cache misses from | ||
415 | other processors. In such cases, the TSC on halted CPUs could advance faster | ||
416 | than that of non-halted processors. AMD Turion processors are known to have | ||
417 | this problem. | ||
418 | |||
419 | 3.6) TSC and STPCLK / T-states | ||
420 | |||
421 | External signals given to the processor may also have the effect of stopping | ||
422 | the TSC. This is typically done for thermal emergency power control to prevent | ||
423 | an overheating condition, and typically, there is no way to detect that this | ||
424 | condition has happened. | ||
425 | |||
426 | 3.7) TSC virtualization - VMX | ||
427 | |||
428 | VMX provides conditional trapping of RDTSC, RDMSR, WRMSR and RDTSCP | ||
429 | instructions, which is enough for full virtualization of TSC in any manner. In | ||
430 | addition, VMX allows passing through the host TSC plus an additional TSC_OFFSET | ||
431 | field specified in the VMCS. Special instructions must be used to read and | ||
432 | write the VMCS field. | ||
433 | |||
434 | 3.8) TSC virtualization - SVM | ||
435 | |||
436 | SVM provides conditional trapping of RDTSC, RDMSR, WRMSR and RDTSCP | ||
437 | instructions, which is enough for full virtualization of TSC in any manner. In | ||
438 | addition, SVM allows passing through the host TSC plus an additional offset | ||
439 | field specified in the SVM control block. | ||
440 | |||
441 | 3.9) TSC feature bits in Linux | ||
442 | |||
443 | In summary, there is no way to guarantee the TSC remains in perfect | ||
444 | synchronization unless it is explicitly guaranteed by the architecture. Even | ||
445 | if so, the TSCs in multi-sockets or NUMA systems may still run independently | ||
446 | despite being locally consistent. | ||
447 | |||
448 | The following feature bits are used by Linux to signal various TSC attributes, | ||
449 | but they can only be taken to be meaningful for UP or single node systems. | ||
450 | |||
451 | X86_FEATURE_TSC : The TSC is available in hardware | ||
452 | X86_FEATURE_RDTSCP : The RDTSCP instruction is available | ||
453 | X86_FEATURE_CONSTANT_TSC : The TSC rate is unchanged with P-states | ||
454 | X86_FEATURE_NONSTOP_TSC : The TSC does not stop in C-states | ||
455 | X86_FEATURE_TSC_RELIABLE : TSC sync checks are skipped (VMware) | ||
456 | |||
457 | 4) Virtualization Problems | ||
458 | |||
459 | Timekeeping is especially problematic for virtualization because a number of | ||
460 | challenges arise. The most obvious problem is that time is now shared between | ||
461 | the host and, potentially, a number of virtual machines. Thus the virtual | ||
462 | operating system does not run with 100% usage of the CPU, despite the fact that | ||
463 | it may very well make that assumption. It may expect it to remain true to very | ||
464 | exacting bounds when interrupt sources are disabled, but in reality only its | ||
465 | virtual interrupt sources are disabled, and the machine may still be preempted | ||
466 | at any time. This causes problems as the passage of real time, the injection | ||
467 | of machine interrupts and the associated clock sources are no longer completely | ||
468 | synchronized with real time. | ||
469 | |||
470 | This same problem can occur on native harware to a degree, as SMM mode may | ||
471 | steal cycles from the naturally on X86 systems when SMM mode is used by the | ||
472 | BIOS, but not in such an extreme fashion. However, the fact that SMM mode may | ||
473 | cause similar problems to virtualization makes it a good justification for | ||
474 | solving many of these problems on bare metal. | ||
475 | |||
476 | 4.1) Interrupt clocking | ||
477 | |||
478 | One of the most immediate problems that occurs with legacy operating systems | ||
479 | is that the system timekeeping routines are often designed to keep track of | ||
480 | time by counting periodic interrupts. These interrupts may come from the PIT | ||
481 | or the RTC, but the problem is the same: the host virtualization engine may not | ||
482 | be able to deliver the proper number of interrupts per second, and so guest | ||
483 | time may fall behind. This is especially problematic if a high interrupt rate | ||
484 | is selected, such as 1000 HZ, which is unfortunately the default for many Linux | ||
485 | guests. | ||
486 | |||
487 | There are three approaches to solving this problem; first, it may be possible | ||
488 | to simply ignore it. Guests which have a separate time source for tracking | ||
489 | 'wall clock' or 'real time' may not need any adjustment of their interrupts to | ||
490 | maintain proper time. If this is not sufficient, it may be necessary to inject | ||
491 | additional interrupts into the guest in order to increase the effective | ||
492 | interrupt rate. This approach leads to complications in extreme conditions, | ||
493 | where host load or guest lag is too much to compensate for, and thus another | ||
494 | solution to the problem has risen: the guest may need to become aware of lost | ||
495 | ticks and compensate for them internally. Although promising in theory, the | ||
496 | implementation of this policy in Linux has been extremely error prone, and a | ||
497 | number of buggy variants of lost tick compensation are distributed across | ||
498 | commonly used Linux systems. | ||
499 | |||
500 | Windows uses periodic RTC clocking as a means of keeping time internally, and | ||
501 | thus requires interrupt slewing to keep proper time. It does use a low enough | ||
502 | rate (ed: is it 18.2 Hz?) however that it has not yet been a problem in | ||
503 | practice. | ||
504 | |||
505 | 4.2) TSC sampling and serialization | ||
506 | |||
507 | As the highest precision time source available, the cycle counter of the CPU | ||
508 | has aroused much interest from developers. As explained above, this timer has | ||
509 | many problems unique to its nature as a local, potentially unstable and | ||
510 | potentially unsynchronized source. One issue which is not unique to the TSC, | ||
511 | but is highlighted because of its very precise nature is sampling delay. By | ||
512 | definition, the counter, once read is already old. However, it is also | ||
513 | possible for the counter to be read ahead of the actual use of the result. | ||
514 | This is a consequence of the superscalar execution of the instruction stream, | ||
515 | which may execute instructions out of order. Such execution is called | ||
516 | non-serialized. Forcing serialized execution is necessary for precise | ||
517 | measurement with the TSC, and requires a serializing instruction, such as CPUID | ||
518 | or an MSR read. | ||
519 | |||
520 | Since CPUID may actually be virtualized by a trap and emulate mechanism, this | ||
521 | serialization can pose a performance issue for hardware virtualization. An | ||
522 | accurate time stamp counter reading may therefore not always be available, and | ||
523 | it may be necessary for an implementation to guard against "backwards" reads of | ||
524 | the TSC as seen from other CPUs, even in an otherwise perfectly synchronized | ||
525 | system. | ||
526 | |||
527 | 4.3) Timespec aliasing | ||
528 | |||
529 | Additionally, this lack of serialization from the TSC poses another challenge | ||
530 | when using results of the TSC when measured against another time source. As | ||
531 | the TSC is much higher precision, many possible values of the TSC may be read | ||
532 | while another clock is still expressing the same value. | ||
533 | |||
534 | That is, you may read (T,T+10) while external clock C maintains the same value. | ||
535 | Due to non-serialized reads, you may actually end up with a range which | ||
536 | fluctuates - from (T-1.. T+10). Thus, any time calculated from a TSC, but | ||
537 | calibrated against an external value may have a range of valid values. | ||
538 | Re-calibrating this computation may actually cause time, as computed after the | ||
539 | calibration, to go backwards, compared with time computed before the | ||
540 | calibration. | ||
541 | |||
542 | This problem is particularly pronounced with an internal time source in Linux, | ||
543 | the kernel time, which is expressed in the theoretically high resolution | ||
544 | timespec - but which advances in much larger granularity intervals, sometimes | ||
545 | at the rate of jiffies, and possibly in catchup modes, at a much larger step. | ||
546 | |||
547 | This aliasing requires care in the computation and recalibration of kvmclock | ||
548 | and any other values derived from TSC computation (such as TSC virtualization | ||
549 | itself). | ||
550 | |||
551 | 4.4) Migration | ||
552 | |||
553 | Migration of a virtual machine raises problems for timekeeping in two ways. | ||
554 | First, the migration itself may take time, during which interrupts cannot be | ||
555 | delivered, and after which, the guest time may need to be caught up. NTP may | ||
556 | be able to help to some degree here, as the clock correction required is | ||
557 | typically small enough to fall in the NTP-correctable window. | ||
558 | |||
559 | An additional concern is that timers based off the TSC (or HPET, if the raw bus | ||
560 | clock is exposed) may now be running at different rates, requiring compensation | ||
561 | in some way in the hypervisor by virtualizing these timers. In addition, | ||
562 | migrating to a faster machine may preclude the use of a passthrough TSC, as a | ||
563 | faster clock cannot be made visible to a guest without the potential of time | ||
564 | advancing faster than usual. A slower clock is less of a problem, as it can | ||
565 | always be caught up to the original rate. KVM clock avoids these problems by | ||
566 | simply storing multipliers and offsets against the TSC for the guest to convert | ||
567 | back into nanosecond resolution values. | ||
568 | |||
569 | 4.5) Scheduling | ||
570 | |||
571 | Since scheduling may be based on precise timing and firing of interrupts, the | ||
572 | scheduling algorithms of an operating system may be adversely affected by | ||
573 | virtualization. In theory, the effect is random and should be universally | ||
574 | distributed, but in contrived as well as real scenarios (guest device access, | ||
575 | causes of virtualization exits, possible context switch), this may not always | ||
576 | be the case. The effect of this has not been well studied. | ||
577 | |||
578 | In an attempt to work around this, several implementations have provided a | ||
579 | paravirtualized scheduler clock, which reveals the true amount of CPU time for | ||
580 | which a virtual machine has been running. | ||
581 | |||
582 | 4.6) Watchdogs | ||
583 | |||
584 | Watchdog timers, such as the lock detector in Linux may fire accidentally when | ||
585 | running under hardware virtualization due to timer interrupts being delayed or | ||
586 | misinterpretation of the passage of real time. Usually, these warnings are | ||
587 | spurious and can be ignored, but in some circumstances it may be necessary to | ||
588 | disable such detection. | ||
589 | |||
590 | 4.7) Delays and precision timing | ||
591 | |||
592 | Precise timing and delays may not be possible in a virtualized system. This | ||
593 | can happen if the system is controlling physical hardware, or issues delays to | ||
594 | compensate for slower I/O to and from devices. The first issue is not solvable | ||
595 | in general for a virtualized system; hardware control software can't be | ||
596 | adequately virtualized without a full real-time operating system, which would | ||
597 | require an RT aware virtualization platform. | ||
598 | |||
599 | The second issue may cause performance problems, but this is unlikely to be a | ||
600 | significant issue. In many cases these delays may be eliminated through | ||
601 | configuration or paravirtualization. | ||
602 | |||
603 | 4.8) Covert channels and leaks | ||
604 | |||
605 | In addition to the above problems, time information will inevitably leak to the | ||
606 | guest about the host in anything but a perfect implementation of virtualized | ||
607 | time. This may allow the guest to infer the presence of a hypervisor (as in a | ||
608 | red-pill type detection), and it may allow information to leak between guests | ||
609 | by using CPU utilization itself as a signalling channel. Preventing such | ||
610 | problems would require completely isolated virtual time which may not track | ||
611 | real time any longer. This may be useful in certain security or QA contexts, | ||
612 | but in general isn't recommended for real-world deployment scenarios. | ||
diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt index f6f80257addb..1565eefd6fd5 100644 --- a/Documentation/laptops/thinkpad-acpi.txt +++ b/Documentation/laptops/thinkpad-acpi.txt | |||
@@ -1024,6 +1024,10 @@ ThinkPad-specific interface. The driver will disable its native | |||
1024 | backlight brightness control interface if it detects that the standard | 1024 | backlight brightness control interface if it detects that the standard |
1025 | ACPI interface is available in the ThinkPad. | 1025 | ACPI interface is available in the ThinkPad. |
1026 | 1026 | ||
1027 | If you want to use the thinkpad-acpi backlight brightness control | ||
1028 | instead of the generic ACPI video backlight brightness control for some | ||
1029 | reason, you should use the acpi_backlight=vendor kernel parameter. | ||
1030 | |||
1027 | The brightness_enable module parameter can be used to control whether | 1031 | The brightness_enable module parameter can be used to control whether |
1028 | the LCD brightness control feature will be enabled when available. | 1032 | the LCD brightness control feature will be enabled when available. |
1029 | brightness_enable=0 forces it to be disabled. brightness_enable=1 | 1033 | brightness_enable=0 forces it to be disabled. brightness_enable=1 |
diff --git a/Documentation/lguest/Makefile b/Documentation/lguest/Makefile index 28c8cdfcafd8..bebac6b4f332 100644 --- a/Documentation/lguest/Makefile +++ b/Documentation/lguest/Makefile | |||
@@ -1,5 +1,6 @@ | |||
1 | # This creates the demonstration utility "lguest" which runs a Linux guest. | 1 | # This creates the demonstration utility "lguest" which runs a Linux guest. |
2 | CFLAGS:=-m32 -Wall -Wmissing-declarations -Wmissing-prototypes -O3 -I../../include -I../../arch/x86/include -U_FORTIFY_SOURCE | 2 | # Missing headers? Add "-I../../include -I../../arch/x86/include" |
3 | CFLAGS:=-m32 -Wall -Wmissing-declarations -Wmissing-prototypes -O3 -U_FORTIFY_SOURCE | ||
3 | 4 | ||
4 | all: lguest | 5 | all: lguest |
5 | 6 | ||
diff --git a/Documentation/lguest/lguest.c b/Documentation/lguest/lguest.c index e9ce3c554514..dc73bc54cc4e 100644 --- a/Documentation/lguest/lguest.c +++ b/Documentation/lguest/lguest.c | |||
@@ -39,14 +39,14 @@ | |||
39 | #include <limits.h> | 39 | #include <limits.h> |
40 | #include <stddef.h> | 40 | #include <stddef.h> |
41 | #include <signal.h> | 41 | #include <signal.h> |
42 | #include "linux/lguest_launcher.h" | 42 | #include <linux/virtio_config.h> |
43 | #include "linux/virtio_config.h" | 43 | #include <linux/virtio_net.h> |
44 | #include "linux/virtio_net.h" | 44 | #include <linux/virtio_blk.h> |
45 | #include "linux/virtio_blk.h" | 45 | #include <linux/virtio_console.h> |
46 | #include "linux/virtio_console.h" | 46 | #include <linux/virtio_rng.h> |
47 | #include "linux/virtio_rng.h" | 47 | #include <linux/virtio_ring.h> |
48 | #include "linux/virtio_ring.h" | 48 | #include <asm/bootparam.h> |
49 | #include "asm/bootparam.h" | 49 | #include "../../include/linux/lguest_launcher.h" |
50 | /*L:110 | 50 | /*L:110 |
51 | * We can ignore the 42 include files we need for this program, but I do want | 51 | * We can ignore the 42 include files we need for this program, but I do want |
52 | * to draw attention to the use of kernel-style types. | 52 | * to draw attention to the use of kernel-style types. |
@@ -1447,14 +1447,15 @@ static void add_to_bridge(int fd, const char *if_name, const char *br_name) | |||
1447 | static void configure_device(int fd, const char *tapif, u32 ipaddr) | 1447 | static void configure_device(int fd, const char *tapif, u32 ipaddr) |
1448 | { | 1448 | { |
1449 | struct ifreq ifr; | 1449 | struct ifreq ifr; |
1450 | struct sockaddr_in *sin = (struct sockaddr_in *)&ifr.ifr_addr; | 1450 | struct sockaddr_in sin; |
1451 | 1451 | ||
1452 | memset(&ifr, 0, sizeof(ifr)); | 1452 | memset(&ifr, 0, sizeof(ifr)); |
1453 | strcpy(ifr.ifr_name, tapif); | 1453 | strcpy(ifr.ifr_name, tapif); |
1454 | 1454 | ||
1455 | /* Don't read these incantations. Just cut & paste them like I did! */ | 1455 | /* Don't read these incantations. Just cut & paste them like I did! */ |
1456 | sin->sin_family = AF_INET; | 1456 | sin.sin_family = AF_INET; |
1457 | sin->sin_addr.s_addr = htonl(ipaddr); | 1457 | sin.sin_addr.s_addr = htonl(ipaddr); |
1458 | memcpy(&ifr.ifr_addr, &sin, sizeof(sin)); | ||
1458 | if (ioctl(fd, SIOCSIFADDR, &ifr) != 0) | 1459 | if (ioctl(fd, SIOCSIFADDR, &ifr) != 0) |
1459 | err(1, "Setting %s interface address", tapif); | 1460 | err(1, "Setting %s interface address", tapif); |
1460 | ifr.ifr_flags = IFF_UP; | 1461 | ifr.ifr_flags = IFF_UP; |
@@ -1639,15 +1640,6 @@ static void blk_request(struct virtqueue *vq) | |||
1639 | off = out->sector * 512; | 1640 | off = out->sector * 512; |
1640 | 1641 | ||
1641 | /* | 1642 | /* |
1642 | * The block device implements "barriers", where the Guest indicates | ||
1643 | * that it wants all previous writes to occur before this write. We | ||
1644 | * don't have a way of asking our kernel to do a barrier, so we just | ||
1645 | * synchronize all the data in the file. Pretty poor, no? | ||
1646 | */ | ||
1647 | if (out->type & VIRTIO_BLK_T_BARRIER) | ||
1648 | fdatasync(vblk->fd); | ||
1649 | |||
1650 | /* | ||
1651 | * In general the virtio block driver is allowed to try SCSI commands. | 1643 | * In general the virtio block driver is allowed to try SCSI commands. |
1652 | * It'd be nice if we supported eject, for example, but we don't. | 1644 | * It'd be nice if we supported eject, for example, but we don't. |
1653 | */ | 1645 | */ |
@@ -1679,6 +1671,13 @@ static void blk_request(struct virtqueue *vq) | |||
1679 | /* Die, bad Guest, die. */ | 1671 | /* Die, bad Guest, die. */ |
1680 | errx(1, "Write past end %llu+%u", off, ret); | 1672 | errx(1, "Write past end %llu+%u", off, ret); |
1681 | } | 1673 | } |
1674 | |||
1675 | wlen = sizeof(*in); | ||
1676 | *in = (ret >= 0 ? VIRTIO_BLK_S_OK : VIRTIO_BLK_S_IOERR); | ||
1677 | } else if (out->type & VIRTIO_BLK_T_FLUSH) { | ||
1678 | /* Flush */ | ||
1679 | ret = fdatasync(vblk->fd); | ||
1680 | verbose("FLUSH fdatasync: %i\n", ret); | ||
1682 | wlen = sizeof(*in); | 1681 | wlen = sizeof(*in); |
1683 | *in = (ret >= 0 ? VIRTIO_BLK_S_OK : VIRTIO_BLK_S_IOERR); | 1682 | *in = (ret >= 0 ? VIRTIO_BLK_S_OK : VIRTIO_BLK_S_IOERR); |
1684 | } else { | 1683 | } else { |
@@ -1702,15 +1701,6 @@ static void blk_request(struct virtqueue *vq) | |||
1702 | } | 1701 | } |
1703 | } | 1702 | } |
1704 | 1703 | ||
1705 | /* | ||
1706 | * OK, so we noted that it was pretty poor to use an fdatasync as a | ||
1707 | * barrier. But Christoph Hellwig points out that we need a sync | ||
1708 | * *afterwards* as well: "Barriers specify no reordering to the front | ||
1709 | * or the back." And Jens Axboe confirmed it, so here we are: | ||
1710 | */ | ||
1711 | if (out->type & VIRTIO_BLK_T_BARRIER) | ||
1712 | fdatasync(vblk->fd); | ||
1713 | |||
1714 | /* Finished that request. */ | 1704 | /* Finished that request. */ |
1715 | add_used(vq, head, wlen); | 1705 | add_used(vq, head, wlen); |
1716 | } | 1706 | } |
@@ -1735,8 +1725,8 @@ static void setup_block_file(const char *filename) | |||
1735 | vblk->fd = open_or_die(filename, O_RDWR|O_LARGEFILE); | 1725 | vblk->fd = open_or_die(filename, O_RDWR|O_LARGEFILE); |
1736 | vblk->len = lseek64(vblk->fd, 0, SEEK_END); | 1726 | vblk->len = lseek64(vblk->fd, 0, SEEK_END); |
1737 | 1727 | ||
1738 | /* We support barriers. */ | 1728 | /* We support FLUSH. */ |
1739 | add_feature(dev, VIRTIO_BLK_F_BARRIER); | 1729 | add_feature(dev, VIRTIO_BLK_F_FLUSH); |
1740 | 1730 | ||
1741 | /* Tell Guest how many sectors this device has. */ | 1731 | /* Tell Guest how many sectors this device has. */ |
1742 | conf.capacity = cpu_to_le64(vblk->len / 512); | 1732 | conf.capacity = cpu_to_le64(vblk->len / 512); |
diff --git a/Documentation/mmc/00-INDEX b/Documentation/mmc/00-INDEX new file mode 100644 index 000000000000..fca586f5b853 --- /dev/null +++ b/Documentation/mmc/00-INDEX | |||
@@ -0,0 +1,4 @@ | |||
1 | 00-INDEX | ||
2 | - this file | ||
3 | mmc-dev-attrs.txt | ||
4 | - info on SD and MMC device attributes | ||
diff --git a/Documentation/mmc/mmc-dev-attrs.txt b/Documentation/mmc/mmc-dev-attrs.txt new file mode 100644 index 000000000000..ff2bd685bced --- /dev/null +++ b/Documentation/mmc/mmc-dev-attrs.txt | |||
@@ -0,0 +1,56 @@ | |||
1 | SD and MMC Device Attributes | ||
2 | ============================ | ||
3 | |||
4 | All attributes are read-only. | ||
5 | |||
6 | cid Card Identifaction Register | ||
7 | csd Card Specific Data Register | ||
8 | scr SD Card Configuration Register (SD only) | ||
9 | date Manufacturing Date (from CID Register) | ||
10 | fwrev Firmware/Product Revision (from CID Register) (SD and MMCv1 only) | ||
11 | hwrev Hardware/Product Revision (from CID Register) (SD and MMCv1 only) | ||
12 | manfid Manufacturer ID (from CID Register) | ||
13 | name Product Name (from CID Register) | ||
14 | oemid OEM/Application ID (from CID Register) | ||
15 | serial Product Serial Number (from CID Register) | ||
16 | erase_size Erase group size | ||
17 | preferred_erase_size Preferred erase size | ||
18 | |||
19 | Note on Erase Size and Preferred Erase Size: | ||
20 | |||
21 | "erase_size" is the minimum size, in bytes, of an erase | ||
22 | operation. For MMC, "erase_size" is the erase group size | ||
23 | reported by the card. Note that "erase_size" does not apply | ||
24 | to trim or secure trim operations where the minimum size is | ||
25 | always one 512 byte sector. For SD, "erase_size" is 512 | ||
26 | if the card is block-addressed, 0 otherwise. | ||
27 | |||
28 | SD/MMC cards can erase an arbitrarily large area up to and | ||
29 | including the whole card. When erasing a large area it may | ||
30 | be desirable to do it in smaller chunks for three reasons: | ||
31 | 1. A single erase command will make all other I/O on | ||
32 | the card wait. This is not a problem if the whole card | ||
33 | is being erased, but erasing one partition will make | ||
34 | I/O for another partition on the same card wait for the | ||
35 | duration of the erase - which could be a several | ||
36 | minutes. | ||
37 | 2. To be able to inform the user of erase progress. | ||
38 | 3. The erase timeout becomes too large to be very | ||
39 | useful. Because the erase timeout contains a margin | ||
40 | which is multiplied by the size of the erase area, | ||
41 | the value can end up being several minutes for large | ||
42 | areas. | ||
43 | |||
44 | "erase_size" is not the most efficient unit to erase | ||
45 | (especially for SD where it is just one sector), | ||
46 | hence "preferred_erase_size" provides a good chunk | ||
47 | size for erasing large areas. | ||
48 | |||
49 | For MMC, "preferred_erase_size" is the high-capacity | ||
50 | erase size if a card specifies one, otherwise it is | ||
51 | based on the capacity of the card. | ||
52 | |||
53 | For SD, "preferred_erase_size" is the allocation unit | ||
54 | size specified by the card. | ||
55 | |||
56 | "preferred_erase_size" is in bytes. | ||
diff --git a/Documentation/mutex-design.txt b/Documentation/mutex-design.txt index c91ccc0720fa..38c10fd7f411 100644 --- a/Documentation/mutex-design.txt +++ b/Documentation/mutex-design.txt | |||
@@ -9,7 +9,7 @@ firstly, there's nothing wrong with semaphores. But if the simpler | |||
9 | mutex semantics are sufficient for your code, then there are a couple | 9 | mutex semantics are sufficient for your code, then there are a couple |
10 | of advantages of mutexes: | 10 | of advantages of mutexes: |
11 | 11 | ||
12 | - 'struct mutex' is smaller on most architectures: .e.g on x86, | 12 | - 'struct mutex' is smaller on most architectures: E.g. on x86, |
13 | 'struct semaphore' is 20 bytes, 'struct mutex' is 16 bytes. | 13 | 'struct semaphore' is 20 bytes, 'struct mutex' is 16 bytes. |
14 | A smaller structure size means less RAM footprint, and better | 14 | A smaller structure size means less RAM footprint, and better |
15 | CPU-cache utilization. | 15 | CPU-cache utilization. |
@@ -136,3 +136,4 @@ the APIs of 'struct mutex' have been streamlined: | |||
136 | void mutex_lock_nested(struct mutex *lock, unsigned int subclass); | 136 | void mutex_lock_nested(struct mutex *lock, unsigned int subclass); |
137 | int mutex_lock_interruptible_nested(struct mutex *lock, | 137 | int mutex_lock_interruptible_nested(struct mutex *lock, |
138 | unsigned int subclass); | 138 | unsigned int subclass); |
139 | int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock); | ||
diff --git a/Documentation/networking/bonding.txt b/Documentation/networking/bonding.txt index d2b62b71b617..5dc638791d97 100644 --- a/Documentation/networking/bonding.txt +++ b/Documentation/networking/bonding.txt | |||
@@ -765,6 +765,14 @@ xmit_hash_policy | |||
765 | does not exist, and the layer2 policy is the only policy. The | 765 | does not exist, and the layer2 policy is the only policy. The |
766 | layer2+3 value was added for bonding version 3.2.2. | 766 | layer2+3 value was added for bonding version 3.2.2. |
767 | 767 | ||
768 | resend_igmp | ||
769 | |||
770 | Specifies the number of IGMP membership reports to be issued after | ||
771 | a failover event. One membership report is issued immediately after | ||
772 | the failover, subsequent packets are sent in each 200ms interval. | ||
773 | |||
774 | The valid range is 0 - 255; the default value is 1. This option | ||
775 | was added for bonding version 3.7.0. | ||
768 | 776 | ||
769 | 3. Configuring Bonding Devices | 777 | 3. Configuring Bonding Devices |
770 | ============================== | 778 | ============================== |
diff --git a/Documentation/networking/can.txt b/Documentation/networking/can.txt index cd79735013f9..5b04b67ddca2 100644 --- a/Documentation/networking/can.txt +++ b/Documentation/networking/can.txt | |||
@@ -22,6 +22,7 @@ This file contains | |||
22 | 4.1.2 RAW socket option CAN_RAW_ERR_FILTER | 22 | 4.1.2 RAW socket option CAN_RAW_ERR_FILTER |
23 | 4.1.3 RAW socket option CAN_RAW_LOOPBACK | 23 | 4.1.3 RAW socket option CAN_RAW_LOOPBACK |
24 | 4.1.4 RAW socket option CAN_RAW_RECV_OWN_MSGS | 24 | 4.1.4 RAW socket option CAN_RAW_RECV_OWN_MSGS |
25 | 4.1.5 RAW socket returned message flags | ||
25 | 4.2 Broadcast Manager protocol sockets (SOCK_DGRAM) | 26 | 4.2 Broadcast Manager protocol sockets (SOCK_DGRAM) |
26 | 4.3 connected transport protocols (SOCK_SEQPACKET) | 27 | 4.3 connected transport protocols (SOCK_SEQPACKET) |
27 | 4.4 unconnected transport protocols (SOCK_DGRAM) | 28 | 4.4 unconnected transport protocols (SOCK_DGRAM) |
@@ -471,6 +472,17 @@ solution for a couple of reasons: | |||
471 | setsockopt(s, SOL_CAN_RAW, CAN_RAW_RECV_OWN_MSGS, | 472 | setsockopt(s, SOL_CAN_RAW, CAN_RAW_RECV_OWN_MSGS, |
472 | &recv_own_msgs, sizeof(recv_own_msgs)); | 473 | &recv_own_msgs, sizeof(recv_own_msgs)); |
473 | 474 | ||
475 | 4.1.5 RAW socket returned message flags | ||
476 | |||
477 | When using recvmsg() call, the msg->msg_flags may contain following flags: | ||
478 | |||
479 | MSG_DONTROUTE: set when the received frame was created on the local host. | ||
480 | |||
481 | MSG_CONFIRM: set when the frame was sent via the socket it is received on. | ||
482 | This flag can be interpreted as a 'transmission confirmation' when the | ||
483 | CAN driver supports the echo of frames on driver level, see 3.2 and 6.2. | ||
484 | In order to receive such messages, CAN_RAW_RECV_OWN_MSGS must be set. | ||
485 | |||
474 | 4.2 Broadcast Manager protocol sockets (SOCK_DGRAM) | 486 | 4.2 Broadcast Manager protocol sockets (SOCK_DGRAM) |
475 | 4.3 connected transport protocols (SOCK_SEQPACKET) | 487 | 4.3 connected transport protocols (SOCK_SEQPACKET) |
476 | 4.4 unconnected transport protocols (SOCK_DGRAM) | 488 | 4.4 unconnected transport protocols (SOCK_DGRAM) |
diff --git a/Documentation/networking/dccp.txt b/Documentation/networking/dccp.txt index a62fdf7a6bff..271d524a4c8d 100644 --- a/Documentation/networking/dccp.txt +++ b/Documentation/networking/dccp.txt | |||
@@ -1,18 +1,20 @@ | |||
1 | DCCP protocol | 1 | DCCP protocol |
2 | ============ | 2 | ============= |
3 | 3 | ||
4 | 4 | ||
5 | Contents | 5 | Contents |
6 | ======== | 6 | ======== |
7 | |||
8 | - Introduction | 7 | - Introduction |
9 | - Missing features | 8 | - Missing features |
10 | - Socket options | 9 | - Socket options |
10 | - Sysctl variables | ||
11 | - IOCTLs | ||
12 | - Other tunables | ||
11 | - Notes | 13 | - Notes |
12 | 14 | ||
15 | |||
13 | Introduction | 16 | Introduction |
14 | ============ | 17 | ============ |
15 | |||
16 | Datagram Congestion Control Protocol (DCCP) is an unreliable, connection | 18 | Datagram Congestion Control Protocol (DCCP) is an unreliable, connection |
17 | oriented protocol designed to solve issues present in UDP and TCP, particularly | 19 | oriented protocol designed to solve issues present in UDP and TCP, particularly |
18 | for real-time and multimedia (streaming) traffic. | 20 | for real-time and multimedia (streaming) traffic. |
@@ -29,9 +31,9 @@ It has a base protocol and pluggable congestion control IDs (CCIDs). | |||
29 | DCCP is a Proposed Standard (RFC 2026), and the homepage for DCCP as a protocol | 31 | DCCP is a Proposed Standard (RFC 2026), and the homepage for DCCP as a protocol |
30 | is at http://www.ietf.org/html.charters/dccp-charter.html | 32 | is at http://www.ietf.org/html.charters/dccp-charter.html |
31 | 33 | ||
34 | |||
32 | Missing features | 35 | Missing features |
33 | ================ | 36 | ================ |
34 | |||
35 | The Linux DCCP implementation does not currently support all the features that are | 37 | The Linux DCCP implementation does not currently support all the features that are |
36 | specified in RFCs 4340...42. | 38 | specified in RFCs 4340...42. |
37 | 39 | ||
@@ -45,7 +47,6 @@ http://linux-net.osdl.org/index.php/DCCP_Testing#Experimental_DCCP_source_tree | |||
45 | 47 | ||
46 | Socket options | 48 | Socket options |
47 | ============== | 49 | ============== |
48 | |||
49 | DCCP_SOCKOPT_SERVICE sets the service. The specification mandates use of | 50 | DCCP_SOCKOPT_SERVICE sets the service. The specification mandates use of |
50 | service codes (RFC 4340, sec. 8.1.2); if this socket option is not set, | 51 | service codes (RFC 4340, sec. 8.1.2); if this socket option is not set, |
51 | the socket will fall back to 0 (which means that no meaningful service code | 52 | the socket will fall back to 0 (which means that no meaningful service code |
@@ -112,6 +113,7 @@ DCCP_SOCKOPT_CCID_TX_INFO | |||
112 | On unidirectional connections it is useful to close the unused half-connection | 113 | On unidirectional connections it is useful to close the unused half-connection |
113 | via shutdown (SHUT_WR or SHUT_RD): this will reduce per-packet processing costs. | 114 | via shutdown (SHUT_WR or SHUT_RD): this will reduce per-packet processing costs. |
114 | 115 | ||
116 | |||
115 | Sysctl variables | 117 | Sysctl variables |
116 | ================ | 118 | ================ |
117 | Several DCCP default parameters can be managed by the following sysctls | 119 | Several DCCP default parameters can be managed by the following sysctls |
@@ -155,15 +157,30 @@ sync_ratelimit = 125 ms | |||
155 | sequence-invalid packets on the same socket (RFC 4340, 7.5.4). The unit | 157 | sequence-invalid packets on the same socket (RFC 4340, 7.5.4). The unit |
156 | of this parameter is milliseconds; a value of 0 disables rate-limiting. | 158 | of this parameter is milliseconds; a value of 0 disables rate-limiting. |
157 | 159 | ||
160 | |||
158 | IOCTLS | 161 | IOCTLS |
159 | ====== | 162 | ====== |
160 | FIONREAD | 163 | FIONREAD |
161 | Works as in udp(7): returns in the `int' argument pointer the size of | 164 | Works as in udp(7): returns in the `int' argument pointer the size of |
162 | the next pending datagram in bytes, or 0 when no datagram is pending. | 165 | the next pending datagram in bytes, or 0 when no datagram is pending. |
163 | 166 | ||
167 | |||
168 | Other tunables | ||
169 | ============== | ||
170 | Per-route rto_min support | ||
171 | CCID-2 supports the RTAX_RTO_MIN per-route setting for the minimum value | ||
172 | of the RTO timer. This setting can be modified via the 'rto_min' option | ||
173 | of iproute2; for example: | ||
174 | > ip route change 10.0.0.0/24 rto_min 250j dev wlan0 | ||
175 | > ip route add 10.0.0.254/32 rto_min 800j dev wlan0 | ||
176 | > ip route show dev wlan0 | ||
177 | CCID-3 also supports the rto_min setting: it is used to define the lower | ||
178 | bound for the expiry of the nofeedback timer. This can be useful on LANs | ||
179 | with very low RTTs (e.g., loopback, Gbit ethernet). | ||
180 | |||
181 | |||
164 | Notes | 182 | Notes |
165 | ===== | 183 | ===== |
166 | |||
167 | DCCP does not travel through NAT successfully at present on many boxes. This is | 184 | DCCP does not travel through NAT successfully at present on many boxes. This is |
168 | because the checksum covers the pseudo-header as per TCP and UDP. Linux NAT | 185 | because the checksum covers the pseudo-header as per TCP and UDP. Linux NAT |
169 | support for DCCP has been added. | 186 | support for DCCP has been added. |
diff --git a/Documentation/networking/e1000.txt b/Documentation/networking/e1000.txt index 2df71861e578..d9271e74e488 100644 --- a/Documentation/networking/e1000.txt +++ b/Documentation/networking/e1000.txt | |||
@@ -1,82 +1,35 @@ | |||
1 | Linux* Base Driver for the Intel(R) PRO/1000 Family of Adapters | 1 | Linux* Base Driver for the Intel(R) PRO/1000 Family of Adapters |
2 | =============================================================== | 2 | =============================================================== |
3 | 3 | ||
4 | September 26, 2006 | 4 | Intel Gigabit Linux driver. |
5 | 5 | Copyright(c) 1999 - 2010 Intel Corporation. | |
6 | 6 | ||
7 | Contents | 7 | Contents |
8 | ======== | 8 | ======== |
9 | 9 | ||
10 | - In This Release | ||
11 | - Identifying Your Adapter | 10 | - Identifying Your Adapter |
12 | - Building and Installation | ||
13 | - Command Line Parameters | 11 | - Command Line Parameters |
14 | - Speed and Duplex Configuration | 12 | - Speed and Duplex Configuration |
15 | - Additional Configurations | 13 | - Additional Configurations |
16 | - Known Issues | ||
17 | - Support | 14 | - Support |
18 | 15 | ||
19 | |||
20 | In This Release | ||
21 | =============== | ||
22 | |||
23 | This file describes the Linux* Base Driver for the Intel(R) PRO/1000 Family | ||
24 | of Adapters. This driver includes support for Itanium(R)2-based systems. | ||
25 | |||
26 | For questions related to hardware requirements, refer to the documentation | ||
27 | supplied with your Intel PRO/1000 adapter. All hardware requirements listed | ||
28 | apply to use with Linux. | ||
29 | |||
30 | The following features are now available in supported kernels: | ||
31 | - Native VLANs | ||
32 | - Channel Bonding (teaming) | ||
33 | - SNMP | ||
34 | |||
35 | Channel Bonding documentation can be found in the Linux kernel source: | ||
36 | /Documentation/networking/bonding.txt | ||
37 | |||
38 | The driver information previously displayed in the /proc filesystem is not | ||
39 | supported in this release. Alternatively, you can use ethtool (version 1.6 | ||
40 | or later), lspci, and ifconfig to obtain the same information. | ||
41 | |||
42 | Instructions on updating ethtool can be found in the section "Additional | ||
43 | Configurations" later in this document. | ||
44 | |||
45 | NOTE: The Intel(R) 82562v 10/100 Network Connection only provides 10/100 | ||
46 | support. | ||
47 | |||
48 | |||
49 | Identifying Your Adapter | 16 | Identifying Your Adapter |
50 | ======================== | 17 | ======================== |
51 | 18 | ||
52 | For more information on how to identify your adapter, go to the Adapter & | 19 | For more information on how to identify your adapter, go to the Adapter & |
53 | Driver ID Guide at: | 20 | Driver ID Guide at: |
54 | 21 | ||
55 | http://support.intel.com/support/network/adapter/pro100/21397.htm | 22 | http://support.intel.com/support/go/network/adapter/idguide.htm |
56 | 23 | ||
57 | For the latest Intel network drivers for Linux, refer to the following | 24 | For the latest Intel network drivers for Linux, refer to the following |
58 | website. In the search field, enter your adapter name or type, or use the | 25 | website. In the search field, enter your adapter name or type, or use the |
59 | networking link on the left to search for your adapter: | 26 | networking link on the left to search for your adapter: |
60 | 27 | ||
61 | http://downloadfinder.intel.com/scripts-df/support_intel.asp | 28 | http://support.intel.com/support/go/network/adapter/home.htm |
62 | |||
63 | 29 | ||
64 | Command Line Parameters | 30 | Command Line Parameters |
65 | ======================= | 31 | ======================= |
66 | 32 | ||
67 | If the driver is built as a module, the following optional parameters | ||
68 | are used by entering them on the command line with the modprobe command | ||
69 | using this syntax: | ||
70 | |||
71 | modprobe e1000 [<option>=<VAL1>,<VAL2>,...] | ||
72 | |||
73 | For example, with two PRO/1000 PCI adapters, entering: | ||
74 | |||
75 | modprobe e1000 TxDescriptors=80,128 | ||
76 | |||
77 | loads the e1000 driver with 80 TX descriptors for the first adapter and | ||
78 | 128 TX descriptors for the second adapter. | ||
79 | |||
80 | The default value for each parameter is generally the recommended setting, | 33 | The default value for each parameter is generally the recommended setting, |
81 | unless otherwise noted. | 34 | unless otherwise noted. |
82 | 35 | ||
@@ -89,10 +42,6 @@ NOTES: For more information about the AutoNeg, Duplex, and Speed | |||
89 | parameters, see the application note at: | 42 | parameters, see the application note at: |
90 | http://www.intel.com/design/network/applnots/ap450.htm | 43 | http://www.intel.com/design/network/applnots/ap450.htm |
91 | 44 | ||
92 | A descriptor describes a data buffer and attributes related to | ||
93 | the data buffer. This information is accessed by the hardware. | ||
94 | |||
95 | |||
96 | AutoNeg | 45 | AutoNeg |
97 | ------- | 46 | ------- |
98 | (Supported only on adapters with copper connections) | 47 | (Supported only on adapters with copper connections) |
@@ -106,7 +55,6 @@ Duplex parameters must not be specified. | |||
106 | NOTE: Refer to the Speed and Duplex section of this readme for more | 55 | NOTE: Refer to the Speed and Duplex section of this readme for more |
107 | information on the AutoNeg parameter. | 56 | information on the AutoNeg parameter. |
108 | 57 | ||
109 | |||
110 | Duplex | 58 | Duplex |
111 | ------ | 59 | ------ |
112 | (Supported only on adapters with copper connections) | 60 | (Supported only on adapters with copper connections) |
@@ -119,7 +67,6 @@ set to auto-negotiate, the board auto-detects the correct duplex. If the | |||
119 | link partner is forced (either full or half), Duplex defaults to half- | 67 | link partner is forced (either full or half), Duplex defaults to half- |
120 | duplex. | 68 | duplex. |
121 | 69 | ||
122 | |||
123 | FlowControl | 70 | FlowControl |
124 | ----------- | 71 | ----------- |
125 | Valid Range: 0-3 (0=none, 1=Rx only, 2=Tx only, 3=Rx&Tx) | 72 | Valid Range: 0-3 (0=none, 1=Rx only, 2=Tx only, 3=Rx&Tx) |
@@ -128,16 +75,16 @@ Default Value: Reads flow control settings from the EEPROM | |||
128 | This parameter controls the automatic generation(Tx) and response(Rx) | 75 | This parameter controls the automatic generation(Tx) and response(Rx) |
129 | to Ethernet PAUSE frames. | 76 | to Ethernet PAUSE frames. |
130 | 77 | ||
131 | |||
132 | InterruptThrottleRate | 78 | InterruptThrottleRate |
133 | --------------------- | 79 | --------------------- |
134 | (not supported on Intel(R) 82542, 82543 or 82544-based adapters) | 80 | (not supported on Intel(R) 82542, 82543 or 82544-based adapters) |
135 | Valid Range: 0,1,3,100-100000 (0=off, 1=dynamic, 3=dynamic conservative) | 81 | Valid Range: 0,1,3,4,100-100000 (0=off, 1=dynamic, 3=dynamic conservative, |
82 | 4=simplified balancing) | ||
136 | Default Value: 3 | 83 | Default Value: 3 |
137 | 84 | ||
138 | The driver can limit the amount of interrupts per second that the adapter | 85 | The driver can limit the amount of interrupts per second that the adapter |
139 | will generate for incoming packets. It does this by writing a value to the | 86 | will generate for incoming packets. It does this by writing a value to the |
140 | adapter that is based on the maximum amount of interrupts that the adapter | 87 | adapter that is based on the maximum amount of interrupts that the adapter |
141 | will generate per second. | 88 | will generate per second. |
142 | 89 | ||
143 | Setting InterruptThrottleRate to a value greater or equal to 100 | 90 | Setting InterruptThrottleRate to a value greater or equal to 100 |
@@ -146,37 +93,43 @@ per second, even if more packets have come in. This reduces interrupt | |||
146 | load on the system and can lower CPU utilization under heavy load, | 93 | load on the system and can lower CPU utilization under heavy load, |
147 | but will increase latency as packets are not processed as quickly. | 94 | but will increase latency as packets are not processed as quickly. |
148 | 95 | ||
149 | The default behaviour of the driver previously assumed a static | 96 | The default behaviour of the driver previously assumed a static |
150 | InterruptThrottleRate value of 8000, providing a good fallback value for | 97 | InterruptThrottleRate value of 8000, providing a good fallback value for |
151 | all traffic types,but lacking in small packet performance and latency. | 98 | all traffic types,but lacking in small packet performance and latency. |
152 | The hardware can handle many more small packets per second however, and | 99 | The hardware can handle many more small packets per second however, and |
153 | for this reason an adaptive interrupt moderation algorithm was implemented. | 100 | for this reason an adaptive interrupt moderation algorithm was implemented. |
154 | 101 | ||
155 | Since 7.3.x, the driver has two adaptive modes (setting 1 or 3) in which | 102 | Since 7.3.x, the driver has two adaptive modes (setting 1 or 3) in which |
156 | it dynamically adjusts the InterruptThrottleRate value based on the traffic | 103 | it dynamically adjusts the InterruptThrottleRate value based on the traffic |
157 | that it receives. After determining the type of incoming traffic in the last | 104 | that it receives. After determining the type of incoming traffic in the last |
158 | timeframe, it will adjust the InterruptThrottleRate to an appropriate value | 105 | timeframe, it will adjust the InterruptThrottleRate to an appropriate value |
159 | for that traffic. | 106 | for that traffic. |
160 | 107 | ||
161 | The algorithm classifies the incoming traffic every interval into | 108 | The algorithm classifies the incoming traffic every interval into |
162 | classes. Once the class is determined, the InterruptThrottleRate value is | 109 | classes. Once the class is determined, the InterruptThrottleRate value is |
163 | adjusted to suit that traffic type the best. There are three classes defined: | 110 | adjusted to suit that traffic type the best. There are three classes defined: |
164 | "Bulk traffic", for large amounts of packets of normal size; "Low latency", | 111 | "Bulk traffic", for large amounts of packets of normal size; "Low latency", |
165 | for small amounts of traffic and/or a significant percentage of small | 112 | for small amounts of traffic and/or a significant percentage of small |
166 | packets; and "Lowest latency", for almost completely small packets or | 113 | packets; and "Lowest latency", for almost completely small packets or |
167 | minimal traffic. | 114 | minimal traffic. |
168 | 115 | ||
169 | In dynamic conservative mode, the InterruptThrottleRate value is set to 4000 | 116 | In dynamic conservative mode, the InterruptThrottleRate value is set to 4000 |
170 | for traffic that falls in class "Bulk traffic". If traffic falls in the "Low | 117 | for traffic that falls in class "Bulk traffic". If traffic falls in the "Low |
171 | latency" or "Lowest latency" class, the InterruptThrottleRate is increased | 118 | latency" or "Lowest latency" class, the InterruptThrottleRate is increased |
172 | stepwise to 20000. This default mode is suitable for most applications. | 119 | stepwise to 20000. This default mode is suitable for most applications. |
173 | 120 | ||
174 | For situations where low latency is vital such as cluster or | 121 | For situations where low latency is vital such as cluster or |
175 | grid computing, the algorithm can reduce latency even more when | 122 | grid computing, the algorithm can reduce latency even more when |
176 | InterruptThrottleRate is set to mode 1. In this mode, which operates | 123 | InterruptThrottleRate is set to mode 1. In this mode, which operates |
177 | the same as mode 3, the InterruptThrottleRate will be increased stepwise to | 124 | the same as mode 3, the InterruptThrottleRate will be increased stepwise to |
178 | 70000 for traffic in class "Lowest latency". | 125 | 70000 for traffic in class "Lowest latency". |
179 | 126 | ||
127 | In simplified mode the interrupt rate is based on the ratio of Tx and | ||
128 | Rx traffic. If the bytes per second rate is approximately equal, the | ||
129 | interrupt rate will drop as low as 2000 interrupts per second. If the | ||
130 | traffic is mostly transmit or mostly receive, the interrupt rate could | ||
131 | be as high as 8000. | ||
132 | |||
180 | Setting InterruptThrottleRate to 0 turns off any interrupt moderation | 133 | Setting InterruptThrottleRate to 0 turns off any interrupt moderation |
181 | and may improve small packet latency, but is generally not suitable | 134 | and may improve small packet latency, but is generally not suitable |
182 | for bulk throughput traffic. | 135 | for bulk throughput traffic. |
@@ -212,8 +165,6 @@ NOTE: When e1000 is loaded with default settings and multiple adapters | |||
212 | be platform-specific. If CPU utilization is not a concern, use | 165 | be platform-specific. If CPU utilization is not a concern, use |
213 | RX_POLLING (NAPI) and default driver settings. | 166 | RX_POLLING (NAPI) and default driver settings. |
214 | 167 | ||
215 | |||
216 | |||
217 | RxDescriptors | 168 | RxDescriptors |
218 | ------------- | 169 | ------------- |
219 | Valid Range: 80-256 for 82542 and 82543-based adapters | 170 | Valid Range: 80-256 for 82542 and 82543-based adapters |
@@ -225,15 +176,14 @@ by the driver. Increasing this value allows the driver to buffer more | |||
225 | incoming packets, at the expense of increased system memory utilization. | 176 | incoming packets, at the expense of increased system memory utilization. |
226 | 177 | ||
227 | Each descriptor is 16 bytes. A receive buffer is also allocated for each | 178 | Each descriptor is 16 bytes. A receive buffer is also allocated for each |
228 | descriptor and can be either 2048, 4096, 8192, or 16384 bytes, depending | 179 | descriptor and can be either 2048, 4096, 8192, or 16384 bytes, depending |
229 | on the MTU setting. The maximum MTU size is 16110. | 180 | on the MTU setting. The maximum MTU size is 16110. |
230 | 181 | ||
231 | NOTE: MTU designates the frame size. It only needs to be set for Jumbo | 182 | NOTE: MTU designates the frame size. It only needs to be set for Jumbo |
232 | Frames. Depending on the available system resources, the request | 183 | Frames. Depending on the available system resources, the request |
233 | for a higher number of receive descriptors may be denied. In this | 184 | for a higher number of receive descriptors may be denied. In this |
234 | case, use a lower number. | 185 | case, use a lower number. |
235 | 186 | ||
236 | |||
237 | RxIntDelay | 187 | RxIntDelay |
238 | ---------- | 188 | ---------- |
239 | Valid Range: 0-65535 (0=off) | 189 | Valid Range: 0-65535 (0=off) |
@@ -254,7 +204,6 @@ CAUTION: When setting RxIntDelay to a value other than 0, adapters may | |||
254 | restoring the network connection. To eliminate the potential | 204 | restoring the network connection. To eliminate the potential |
255 | for the hang ensure that RxIntDelay is set to 0. | 205 | for the hang ensure that RxIntDelay is set to 0. |
256 | 206 | ||
257 | |||
258 | RxAbsIntDelay | 207 | RxAbsIntDelay |
259 | ------------- | 208 | ------------- |
260 | (This parameter is supported only on 82540, 82545 and later adapters.) | 209 | (This parameter is supported only on 82540, 82545 and later adapters.) |
@@ -268,7 +217,6 @@ packet is received within the set amount of time. Proper tuning, | |||
268 | along with RxIntDelay, may improve traffic throughput in specific network | 217 | along with RxIntDelay, may improve traffic throughput in specific network |
269 | conditions. | 218 | conditions. |
270 | 219 | ||
271 | |||
272 | Speed | 220 | Speed |
273 | ----- | 221 | ----- |
274 | (This parameter is supported only on adapters with copper connections.) | 222 | (This parameter is supported only on adapters with copper connections.) |
@@ -280,7 +228,6 @@ Speed forces the line speed to the specified value in megabits per second | |||
280 | partner is set to auto-negotiate, the board will auto-detect the correct | 228 | partner is set to auto-negotiate, the board will auto-detect the correct |
281 | speed. Duplex should also be set when Speed is set to either 10 or 100. | 229 | speed. Duplex should also be set when Speed is set to either 10 or 100. |
282 | 230 | ||
283 | |||
284 | TxDescriptors | 231 | TxDescriptors |
285 | ------------- | 232 | ------------- |
286 | Valid Range: 80-256 for 82542 and 82543-based adapters | 233 | Valid Range: 80-256 for 82542 and 82543-based adapters |
@@ -295,6 +242,36 @@ NOTE: Depending on the available system resources, the request for a | |||
295 | higher number of transmit descriptors may be denied. In this case, | 242 | higher number of transmit descriptors may be denied. In this case, |
296 | use a lower number. | 243 | use a lower number. |
297 | 244 | ||
245 | TxDescriptorStep | ||
246 | ---------------- | ||
247 | Valid Range: 1 (use every Tx Descriptor) | ||
248 | 4 (use every 4th Tx Descriptor) | ||
249 | |||
250 | Default Value: 1 (use every Tx Descriptor) | ||
251 | |||
252 | On certain non-Intel architectures, it has been observed that intense TX | ||
253 | traffic bursts of short packets may result in an improper descriptor | ||
254 | writeback. If this occurs, the driver will report a "TX Timeout" and reset | ||
255 | the adapter, after which the transmit flow will restart, though data may | ||
256 | have stalled for as much as 10 seconds before it resumes. | ||
257 | |||
258 | The improper writeback does not occur on the first descriptor in a system | ||
259 | memory cache-line, which is typically 32 bytes, or 4 descriptors long. | ||
260 | |||
261 | Setting TxDescriptorStep to a value of 4 will ensure that all TX descriptors | ||
262 | are aligned to the start of a system memory cache line, and so this problem | ||
263 | will not occur. | ||
264 | |||
265 | NOTES: Setting TxDescriptorStep to 4 effectively reduces the number of | ||
266 | TxDescriptors available for transmits to 1/4 of the normal allocation. | ||
267 | This has a possible negative performance impact, which may be | ||
268 | compensated for by allocating more descriptors using the TxDescriptors | ||
269 | module parameter. | ||
270 | |||
271 | There are other conditions which may result in "TX Timeout", which will | ||
272 | not be resolved by the use of the TxDescriptorStep parameter. As the | ||
273 | issue addressed by this parameter has never been observed on Intel | ||
274 | Architecture platforms, it should not be used on Intel platforms. | ||
298 | 275 | ||
299 | TxIntDelay | 276 | TxIntDelay |
300 | ---------- | 277 | ---------- |
@@ -307,7 +284,6 @@ efficiency if properly tuned for specific network traffic. If the | |||
307 | system is reporting dropped transmits, this value may be set too high | 284 | system is reporting dropped transmits, this value may be set too high |
308 | causing the driver to run out of available transmit descriptors. | 285 | causing the driver to run out of available transmit descriptors. |
309 | 286 | ||
310 | |||
311 | TxAbsIntDelay | 287 | TxAbsIntDelay |
312 | ------------- | 288 | ------------- |
313 | (This parameter is supported only on 82540, 82545 and later adapters.) | 289 | (This parameter is supported only on 82540, 82545 and later adapters.) |
@@ -330,6 +306,35 @@ Default Value: 1 | |||
330 | A value of '1' indicates that the driver should enable IP checksum | 306 | A value of '1' indicates that the driver should enable IP checksum |
331 | offload for received packets (both UDP and TCP) to the adapter hardware. | 307 | offload for received packets (both UDP and TCP) to the adapter hardware. |
332 | 308 | ||
309 | Copybreak | ||
310 | --------- | ||
311 | Valid Range: 0-xxxxxxx (0=off) | ||
312 | Default Value: 256 | ||
313 | Usage: insmod e1000.ko copybreak=128 | ||
314 | |||
315 | Driver copies all packets below or equaling this size to a fresh Rx | ||
316 | buffer before handing it up the stack. | ||
317 | |||
318 | This parameter is different than other parameters, in that it is a | ||
319 | single (not 1,1,1 etc.) parameter applied to all driver instances and | ||
320 | it is also available during runtime at | ||
321 | /sys/module/e1000/parameters/copybreak | ||
322 | |||
323 | SmartPowerDownEnable | ||
324 | -------------------- | ||
325 | Valid Range: 0-1 | ||
326 | Default Value: 0 (disabled) | ||
327 | |||
328 | Allows PHY to turn off in lower power states. The user can turn off | ||
329 | this parameter in supported chipsets. | ||
330 | |||
331 | KumeranLockLoss | ||
332 | --------------- | ||
333 | Valid Range: 0-1 | ||
334 | Default Value: 1 (enabled) | ||
335 | |||
336 | This workaround skips resetting the PHY at shutdown for the initial | ||
337 | silicon releases of ICH8 systems. | ||
333 | 338 | ||
334 | Speed and Duplex Configuration | 339 | Speed and Duplex Configuration |
335 | ============================== | 340 | ============================== |
@@ -385,40 +390,9 @@ If the link partner is forced to a specific speed and duplex, then this | |||
385 | parameter should not be used. Instead, use the Speed and Duplex parameters | 390 | parameter should not be used. Instead, use the Speed and Duplex parameters |
386 | previously mentioned to force the adapter to the same speed and duplex. | 391 | previously mentioned to force the adapter to the same speed and duplex. |
387 | 392 | ||
388 | |||
389 | Additional Configurations | 393 | Additional Configurations |
390 | ========================= | 394 | ========================= |
391 | 395 | ||
392 | Configuring the Driver on Different Distributions | ||
393 | ------------------------------------------------- | ||
394 | Configuring a network driver to load properly when the system is started | ||
395 | is distribution dependent. Typically, the configuration process involves | ||
396 | adding an alias line to /etc/modules.conf or /etc/modprobe.conf as well | ||
397 | as editing other system startup scripts and/or configuration files. Many | ||
398 | popular Linux distributions ship with tools to make these changes for you. | ||
399 | To learn the proper way to configure a network device for your system, | ||
400 | refer to your distribution documentation. If during this process you are | ||
401 | asked for the driver or module name, the name for the Linux Base Driver | ||
402 | for the Intel(R) PRO/1000 Family of Adapters is e1000. | ||
403 | |||
404 | As an example, if you install the e1000 driver for two PRO/1000 adapters | ||
405 | (eth0 and eth1) and set the speed and duplex to 10full and 100half, add | ||
406 | the following to modules.conf or or modprobe.conf: | ||
407 | |||
408 | alias eth0 e1000 | ||
409 | alias eth1 e1000 | ||
410 | options e1000 Speed=10,100 Duplex=2,1 | ||
411 | |||
412 | Viewing Link Messages | ||
413 | --------------------- | ||
414 | Link messages will not be displayed to the console if the distribution is | ||
415 | restricting system messages. In order to see network driver link messages | ||
416 | on your console, set dmesg to eight by entering the following: | ||
417 | |||
418 | dmesg -n 8 | ||
419 | |||
420 | NOTE: This setting is not saved across reboots. | ||
421 | |||
422 | Jumbo Frames | 396 | Jumbo Frames |
423 | ------------ | 397 | ------------ |
424 | Jumbo Frames support is enabled by changing the MTU to a value larger than | 398 | Jumbo Frames support is enabled by changing the MTU to a value larger than |
@@ -437,9 +411,11 @@ Additional Configurations | |||
437 | setting in a different location. | 411 | setting in a different location. |
438 | 412 | ||
439 | Notes: | 413 | Notes: |
440 | 414 | Degradation in throughput performance may be observed in some Jumbo frames | |
441 | - To enable Jumbo Frames, increase the MTU size on the interface beyond | 415 | environments. If this is observed, increasing the application's socket buffer |
442 | 1500. | 416 | size and/or increasing the /proc/sys/net/ipv4/tcp_*mem entry values may help. |
417 | See the specific application manual and /usr/src/linux*/Documentation/ | ||
418 | networking/ip-sysctl.txt for more details. | ||
443 | 419 | ||
444 | - The maximum MTU setting for Jumbo Frames is 16110. This value coincides | 420 | - The maximum MTU setting for Jumbo Frames is 16110. This value coincides |
445 | with the maximum Jumbo Frames size of 16128. | 421 | with the maximum Jumbo Frames size of 16128. |
@@ -447,40 +423,11 @@ Additional Configurations | |||
447 | - Using Jumbo Frames at 10 or 100 Mbps may result in poor performance or | 423 | - Using Jumbo Frames at 10 or 100 Mbps may result in poor performance or |
448 | loss of link. | 424 | loss of link. |
449 | 425 | ||
450 | - Some Intel gigabit adapters that support Jumbo Frames have a frame size | ||
451 | limit of 9238 bytes, with a corresponding MTU size limit of 9216 bytes. | ||
452 | The adapters with this limitation are based on the Intel(R) 82571EB, | ||
453 | 82572EI, 82573L and 80003ES2LAN controller. These correspond to the | ||
454 | following product names: | ||
455 | Intel(R) PRO/1000 PT Server Adapter | ||
456 | Intel(R) PRO/1000 PT Desktop Adapter | ||
457 | Intel(R) PRO/1000 PT Network Connection | ||
458 | Intel(R) PRO/1000 PT Dual Port Server Adapter | ||
459 | Intel(R) PRO/1000 PT Dual Port Network Connection | ||
460 | Intel(R) PRO/1000 PF Server Adapter | ||
461 | Intel(R) PRO/1000 PF Network Connection | ||
462 | Intel(R) PRO/1000 PF Dual Port Server Adapter | ||
463 | Intel(R) PRO/1000 PB Server Connection | ||
464 | Intel(R) PRO/1000 PL Network Connection | ||
465 | Intel(R) PRO/1000 EB Network Connection with I/O Acceleration | ||
466 | Intel(R) PRO/1000 EB Backplane Connection with I/O Acceleration | ||
467 | Intel(R) PRO/1000 PT Quad Port Server Adapter | ||
468 | |||
469 | - Adapters based on the Intel(R) 82542 and 82573V/E controller do not | 426 | - Adapters based on the Intel(R) 82542 and 82573V/E controller do not |
470 | support Jumbo Frames. These correspond to the following product names: | 427 | support Jumbo Frames. These correspond to the following product names: |
471 | Intel(R) PRO/1000 Gigabit Server Adapter | 428 | Intel(R) PRO/1000 Gigabit Server Adapter |
472 | Intel(R) PRO/1000 PM Network Connection | 429 | Intel(R) PRO/1000 PM Network Connection |
473 | 430 | ||
474 | - The following adapters do not support Jumbo Frames: | ||
475 | Intel(R) 82562V 10/100 Network Connection | ||
476 | Intel(R) 82566DM Gigabit Network Connection | ||
477 | Intel(R) 82566DC Gigabit Network Connection | ||
478 | Intel(R) 82566MM Gigabit Network Connection | ||
479 | Intel(R) 82566MC Gigabit Network Connection | ||
480 | Intel(R) 82562GT 10/100 Network Connection | ||
481 | Intel(R) 82562G 10/100 Network Connection | ||
482 | |||
483 | |||
484 | Ethtool | 431 | Ethtool |
485 | ------- | 432 | ------- |
486 | The driver utilizes the ethtool interface for driver configuration and | 433 | The driver utilizes the ethtool interface for driver configuration and |
@@ -490,142 +437,14 @@ Additional Configurations | |||
490 | The latest release of ethtool can be found from | 437 | The latest release of ethtool can be found from |
491 | http://sourceforge.net/projects/gkernel. | 438 | http://sourceforge.net/projects/gkernel. |
492 | 439 | ||
493 | NOTE: Ethtool 1.6 only supports a limited set of ethtool options. Support | ||
494 | for a more complete ethtool feature set can be enabled by upgrading | ||
495 | ethtool to ethtool-1.8.1. | ||
496 | |||
497 | Enabling Wake on LAN* (WoL) | 440 | Enabling Wake on LAN* (WoL) |
498 | --------------------------- | 441 | --------------------------- |
499 | WoL is configured through the Ethtool* utility. Ethtool is included with | 442 | WoL is configured through the Ethtool* utility. |
500 | all versions of Red Hat after Red Hat 7.2. For other Linux distributions, | ||
501 | download and install Ethtool from the following website: | ||
502 | http://sourceforge.net/projects/gkernel. | ||
503 | |||
504 | For instructions on enabling WoL with Ethtool, refer to the website listed | ||
505 | above. | ||
506 | 443 | ||
507 | WoL will be enabled on the system during the next shut down or reboot. | 444 | WoL will be enabled on the system during the next shut down or reboot. |
508 | For this driver version, in order to enable WoL, the e1000 driver must be | 445 | For this driver version, in order to enable WoL, the e1000 driver must be |
509 | loaded when shutting down or rebooting the system. | 446 | loaded when shutting down or rebooting the system. |
510 | 447 | ||
511 | Wake On LAN is only supported on port A for the following devices: | ||
512 | Intel(R) PRO/1000 PT Dual Port Network Connection | ||
513 | Intel(R) PRO/1000 PT Dual Port Server Connection | ||
514 | Intel(R) PRO/1000 PT Dual Port Server Adapter | ||
515 | Intel(R) PRO/1000 PF Dual Port Server Adapter | ||
516 | Intel(R) PRO/1000 PT Quad Port Server Adapter | ||
517 | |||
518 | NAPI | ||
519 | ---- | ||
520 | NAPI (Rx polling mode) is enabled in the e1000 driver. | ||
521 | |||
522 | See www.cyberus.ca/~hadi/usenix-paper.tgz for more information on NAPI. | ||
523 | |||
524 | |||
525 | Known Issues | ||
526 | ============ | ||
527 | |||
528 | Dropped Receive Packets on Half-duplex 10/100 Networks | ||
529 | ------------------------------------------------------ | ||
530 | If you have an Intel PCI Express adapter running at 10mbps or 100mbps, half- | ||
531 | duplex, you may observe occasional dropped receive packets. There are no | ||
532 | workarounds for this problem in this network configuration. The network must | ||
533 | be updated to operate in full-duplex, and/or 1000mbps only. | ||
534 | |||
535 | Jumbo Frames System Requirement | ||
536 | ------------------------------- | ||
537 | Memory allocation failures have been observed on Linux systems with 64 MB | ||
538 | of RAM or less that are running Jumbo Frames. If you are using Jumbo | ||
539 | Frames, your system may require more than the advertised minimum | ||
540 | requirement of 64 MB of system memory. | ||
541 | |||
542 | Performance Degradation with Jumbo Frames | ||
543 | ----------------------------------------- | ||
544 | Degradation in throughput performance may be observed in some Jumbo frames | ||
545 | environments. If this is observed, increasing the application's socket | ||
546 | buffer size and/or increasing the /proc/sys/net/ipv4/tcp_*mem entry values | ||
547 | may help. See the specific application manual and | ||
548 | /usr/src/linux*/Documentation/ | ||
549 | networking/ip-sysctl.txt for more details. | ||
550 | |||
551 | Jumbo Frames on Foundry BigIron 8000 switch | ||
552 | ------------------------------------------- | ||
553 | There is a known issue using Jumbo frames when connected to a Foundry | ||
554 | BigIron 8000 switch. This is a 3rd party limitation. If you experience | ||
555 | loss of packets, lower the MTU size. | ||
556 | |||
557 | Allocating Rx Buffers when Using Jumbo Frames | ||
558 | --------------------------------------------- | ||
559 | Allocating Rx buffers when using Jumbo Frames on 2.6.x kernels may fail if | ||
560 | the available memory is heavily fragmented. This issue may be seen with PCI-X | ||
561 | adapters or with packet split disabled. This can be reduced or eliminated | ||
562 | by changing the amount of available memory for receive buffer allocation, by | ||
563 | increasing /proc/sys/vm/min_free_kbytes. | ||
564 | |||
565 | Multiple Interfaces on Same Ethernet Broadcast Network | ||
566 | ------------------------------------------------------ | ||
567 | Due to the default ARP behavior on Linux, it is not possible to have | ||
568 | one system on two IP networks in the same Ethernet broadcast domain | ||
569 | (non-partitioned switch) behave as expected. All Ethernet interfaces | ||
570 | will respond to IP traffic for any IP address assigned to the system. | ||
571 | This results in unbalanced receive traffic. | ||
572 | |||
573 | If you have multiple interfaces in a server, either turn on ARP | ||
574 | filtering by entering: | ||
575 | |||
576 | echo 1 > /proc/sys/net/ipv4/conf/all/arp_filter | ||
577 | (this only works if your kernel's version is higher than 2.4.5), | ||
578 | |||
579 | NOTE: This setting is not saved across reboots. The configuration | ||
580 | change can be made permanent by adding the line: | ||
581 | net.ipv4.conf.all.arp_filter = 1 | ||
582 | to the file /etc/sysctl.conf | ||
583 | |||
584 | or, | ||
585 | |||
586 | install the interfaces in separate broadcast domains (either in | ||
587 | different switches or in a switch partitioned to VLANs). | ||
588 | |||
589 | 82541/82547 can't link or are slow to link with some link partners | ||
590 | ----------------------------------------------------------------- | ||
591 | There is a known compatibility issue with 82541/82547 and some | ||
592 | low-end switches where the link will not be established, or will | ||
593 | be slow to establish. In particular, these switches are known to | ||
594 | be incompatible with 82541/82547: | ||
595 | |||
596 | Planex FXG-08TE | ||
597 | I-O Data ETG-SH8 | ||
598 | |||
599 | To workaround this issue, the driver can be compiled with an override | ||
600 | of the PHY's master/slave setting. Forcing master or forcing slave | ||
601 | mode will improve time-to-link. | ||
602 | |||
603 | # make CFLAGS_EXTRA=-DE1000_MASTER_SLAVE=<n> | ||
604 | |||
605 | Where <n> is: | ||
606 | |||
607 | 0 = Hardware default | ||
608 | 1 = Master mode | ||
609 | 2 = Slave mode | ||
610 | 3 = Auto master/slave | ||
611 | |||
612 | Disable rx flow control with ethtool | ||
613 | ------------------------------------ | ||
614 | In order to disable receive flow control using ethtool, you must turn | ||
615 | off auto-negotiation on the same command line. | ||
616 | |||
617 | For example: | ||
618 | |||
619 | ethtool -A eth? autoneg off rx off | ||
620 | |||
621 | Unplugging network cable while ethtool -p is running | ||
622 | ---------------------------------------------------- | ||
623 | In kernel versions 2.5.50 and later (including 2.6 kernel), unplugging | ||
624 | the network cable while ethtool -p is running will cause the system to | ||
625 | become unresponsive to keyboard commands, except for control-alt-delete. | ||
626 | Restarting the system appears to be the only remedy. | ||
627 | |||
628 | |||
629 | Support | 448 | Support |
630 | ======= | 449 | ======= |
631 | 450 | ||
diff --git a/Documentation/networking/e1000e.txt b/Documentation/networking/e1000e.txt new file mode 100644 index 000000000000..6aa048badf32 --- /dev/null +++ b/Documentation/networking/e1000e.txt | |||
@@ -0,0 +1,302 @@ | |||
1 | Linux* Driver for Intel(R) Network Connection | ||
2 | =============================================================== | ||
3 | |||
4 | Intel Gigabit Linux driver. | ||
5 | Copyright(c) 1999 - 2010 Intel Corporation. | ||
6 | |||
7 | Contents | ||
8 | ======== | ||
9 | |||
10 | - Identifying Your Adapter | ||
11 | - Command Line Parameters | ||
12 | - Additional Configurations | ||
13 | - Support | ||
14 | |||
15 | Identifying Your Adapter | ||
16 | ======================== | ||
17 | |||
18 | The e1000e driver supports all PCI Express Intel(R) Gigabit Network | ||
19 | Connections, except those that are 82575, 82576 and 82580-based*. | ||
20 | |||
21 | * NOTE: The Intel(R) PRO/1000 P Dual Port Server Adapter is supported by | ||
22 | the e1000 driver, not the e1000e driver due to the 82546 part being used | ||
23 | behind a PCI Express bridge. | ||
24 | |||
25 | For more information on how to identify your adapter, go to the Adapter & | ||
26 | Driver ID Guide at: | ||
27 | |||
28 | http://support.intel.com/support/go/network/adapter/idguide.htm | ||
29 | |||
30 | For the latest Intel network drivers for Linux, refer to the following | ||
31 | website. In the search field, enter your adapter name or type, or use the | ||
32 | networking link on the left to search for your adapter: | ||
33 | |||
34 | http://support.intel.com/support/go/network/adapter/home.htm | ||
35 | |||
36 | Command Line Parameters | ||
37 | ======================= | ||
38 | |||
39 | The default value for each parameter is generally the recommended setting, | ||
40 | unless otherwise noted. | ||
41 | |||
42 | NOTES: For more information about the InterruptThrottleRate, | ||
43 | RxIntDelay, TxIntDelay, RxAbsIntDelay, and TxAbsIntDelay | ||
44 | parameters, see the application note at: | ||
45 | http://www.intel.com/design/network/applnots/ap450.htm | ||
46 | |||
47 | InterruptThrottleRate | ||
48 | --------------------- | ||
49 | Valid Range: 0,1,3,4,100-100000 (0=off, 1=dynamic, 3=dynamic conservative, | ||
50 | 4=simplified balancing) | ||
51 | Default Value: 3 | ||
52 | |||
53 | The driver can limit the amount of interrupts per second that the adapter | ||
54 | will generate for incoming packets. It does this by writing a value to the | ||
55 | adapter that is based on the maximum amount of interrupts that the adapter | ||
56 | will generate per second. | ||
57 | |||
58 | Setting InterruptThrottleRate to a value greater or equal to 100 | ||
59 | will program the adapter to send out a maximum of that many interrupts | ||
60 | per second, even if more packets have come in. This reduces interrupt | ||
61 | load on the system and can lower CPU utilization under heavy load, | ||
62 | but will increase latency as packets are not processed as quickly. | ||
63 | |||
64 | The driver has two adaptive modes (setting 1 or 3) in which | ||
65 | it dynamically adjusts the InterruptThrottleRate value based on the traffic | ||
66 | that it receives. After determining the type of incoming traffic in the last | ||
67 | timeframe, it will adjust the InterruptThrottleRate to an appropriate value | ||
68 | for that traffic. | ||
69 | |||
70 | The algorithm classifies the incoming traffic every interval into | ||
71 | classes. Once the class is determined, the InterruptThrottleRate value is | ||
72 | adjusted to suit that traffic type the best. There are three classes defined: | ||
73 | "Bulk traffic", for large amounts of packets of normal size; "Low latency", | ||
74 | for small amounts of traffic and/or a significant percentage of small | ||
75 | packets; and "Lowest latency", for almost completely small packets or | ||
76 | minimal traffic. | ||
77 | |||
78 | In dynamic conservative mode, the InterruptThrottleRate value is set to 4000 | ||
79 | for traffic that falls in class "Bulk traffic". If traffic falls in the "Low | ||
80 | latency" or "Lowest latency" class, the InterruptThrottleRate is increased | ||
81 | stepwise to 20000. This default mode is suitable for most applications. | ||
82 | |||
83 | For situations where low latency is vital such as cluster or | ||
84 | grid computing, the algorithm can reduce latency even more when | ||
85 | InterruptThrottleRate is set to mode 1. In this mode, which operates | ||
86 | the same as mode 3, the InterruptThrottleRate will be increased stepwise to | ||
87 | 70000 for traffic in class "Lowest latency". | ||
88 | |||
89 | In simplified mode the interrupt rate is based on the ratio of Tx and | ||
90 | Rx traffic. If the bytes per second rate is approximately equal the | ||
91 | interrupt rate will drop as low as 2000 interrupts per second. If the | ||
92 | traffic is mostly transmit or mostly receive, the interrupt rate could | ||
93 | be as high as 8000. | ||
94 | |||
95 | Setting InterruptThrottleRate to 0 turns off any interrupt moderation | ||
96 | and may improve small packet latency, but is generally not suitable | ||
97 | for bulk throughput traffic. | ||
98 | |||
99 | NOTE: InterruptThrottleRate takes precedence over the TxAbsIntDelay and | ||
100 | RxAbsIntDelay parameters. In other words, minimizing the receive | ||
101 | and/or transmit absolute delays does not force the controller to | ||
102 | generate more interrupts than what the Interrupt Throttle Rate | ||
103 | allows. | ||
104 | |||
105 | NOTE: When e1000e is loaded with default settings and multiple adapters | ||
106 | are in use simultaneously, the CPU utilization may increase non- | ||
107 | linearly. In order to limit the CPU utilization without impacting | ||
108 | the overall throughput, we recommend that you load the driver as | ||
109 | follows: | ||
110 | |||
111 | modprobe e1000e InterruptThrottleRate=3000,3000,3000 | ||
112 | |||
113 | This sets the InterruptThrottleRate to 3000 interrupts/sec for | ||
114 | the first, second, and third instances of the driver. The range | ||
115 | of 2000 to 3000 interrupts per second works on a majority of | ||
116 | systems and is a good starting point, but the optimal value will | ||
117 | be platform-specific. If CPU utilization is not a concern, use | ||
118 | RX_POLLING (NAPI) and default driver settings. | ||
119 | |||
120 | RxIntDelay | ||
121 | ---------- | ||
122 | Valid Range: 0-65535 (0=off) | ||
123 | Default Value: 0 | ||
124 | |||
125 | This value delays the generation of receive interrupts in units of 1.024 | ||
126 | microseconds. Receive interrupt reduction can improve CPU efficiency if | ||
127 | properly tuned for specific network traffic. Increasing this value adds | ||
128 | extra latency to frame reception and can end up decreasing the throughput | ||
129 | of TCP traffic. If the system is reporting dropped receives, this value | ||
130 | may be set too high, causing the driver to run out of available receive | ||
131 | descriptors. | ||
132 | |||
133 | CAUTION: When setting RxIntDelay to a value other than 0, adapters may | ||
134 | hang (stop transmitting) under certain network conditions. If | ||
135 | this occurs a NETDEV WATCHDOG message is logged in the system | ||
136 | event log. In addition, the controller is automatically reset, | ||
137 | restoring the network connection. To eliminate the potential | ||
138 | for the hang ensure that RxIntDelay is set to 0. | ||
139 | |||
140 | RxAbsIntDelay | ||
141 | ------------- | ||
142 | Valid Range: 0-65535 (0=off) | ||
143 | Default Value: 8 | ||
144 | |||
145 | This value, in units of 1.024 microseconds, limits the delay in which a | ||
146 | receive interrupt is generated. Useful only if RxIntDelay is non-zero, | ||
147 | this value ensures that an interrupt is generated after the initial | ||
148 | packet is received within the set amount of time. Proper tuning, | ||
149 | along with RxIntDelay, may improve traffic throughput in specific network | ||
150 | conditions. | ||
151 | |||
152 | TxIntDelay | ||
153 | ---------- | ||
154 | Valid Range: 0-65535 (0=off) | ||
155 | Default Value: 8 | ||
156 | |||
157 | This value delays the generation of transmit interrupts in units of | ||
158 | 1.024 microseconds. Transmit interrupt reduction can improve CPU | ||
159 | efficiency if properly tuned for specific network traffic. If the | ||
160 | system is reporting dropped transmits, this value may be set too high | ||
161 | causing the driver to run out of available transmit descriptors. | ||
162 | |||
163 | TxAbsIntDelay | ||
164 | ------------- | ||
165 | Valid Range: 0-65535 (0=off) | ||
166 | Default Value: 32 | ||
167 | |||
168 | This value, in units of 1.024 microseconds, limits the delay in which a | ||
169 | transmit interrupt is generated. Useful only if TxIntDelay is non-zero, | ||
170 | this value ensures that an interrupt is generated after the initial | ||
171 | packet is sent on the wire within the set amount of time. Proper tuning, | ||
172 | along with TxIntDelay, may improve traffic throughput in specific | ||
173 | network conditions. | ||
174 | |||
175 | Copybreak | ||
176 | --------- | ||
177 | Valid Range: 0-xxxxxxx (0=off) | ||
178 | Default Value: 256 | ||
179 | |||
180 | Driver copies all packets below or equaling this size to a fresh Rx | ||
181 | buffer before handing it up the stack. | ||
182 | |||
183 | This parameter is different than other parameters, in that it is a | ||
184 | single (not 1,1,1 etc.) parameter applied to all driver instances and | ||
185 | it is also available during runtime at | ||
186 | /sys/module/e1000e/parameters/copybreak | ||
187 | |||
188 | SmartPowerDownEnable | ||
189 | -------------------- | ||
190 | Valid Range: 0-1 | ||
191 | Default Value: 0 (disabled) | ||
192 | |||
193 | Allows PHY to turn off in lower power states. The user can set this parameter | ||
194 | in supported chipsets. | ||
195 | |||
196 | KumeranLockLoss | ||
197 | --------------- | ||
198 | Valid Range: 0-1 | ||
199 | Default Value: 1 (enabled) | ||
200 | |||
201 | This workaround skips resetting the PHY at shutdown for the initial | ||
202 | silicon releases of ICH8 systems. | ||
203 | |||
204 | IntMode | ||
205 | ------- | ||
206 | Valid Range: 0-2 (0=legacy, 1=MSI, 2=MSI-X) | ||
207 | Default Value: 2 | ||
208 | |||
209 | Allows changing the interrupt mode at module load time, without requiring a | ||
210 | recompile. If the driver load fails to enable a specific interrupt mode, the | ||
211 | driver will try other interrupt modes, from least to most compatible. The | ||
212 | interrupt order is MSI-X, MSI, Legacy. If specifying MSI (IntMode=1) | ||
213 | interrupts, only MSI and Legacy will be attempted. | ||
214 | |||
215 | CrcStripping | ||
216 | ------------ | ||
217 | Valid Range: 0-1 | ||
218 | Default Value: 1 (enabled) | ||
219 | |||
220 | Strip the CRC from received packets before sending up the network stack. If | ||
221 | you have a machine with a BMC enabled but cannot receive IPMI traffic after | ||
222 | loading or enabling the driver, try disabling this feature. | ||
223 | |||
224 | WriteProtectNVM | ||
225 | --------------- | ||
226 | Valid Range: 0-1 | ||
227 | Default Value: 1 (enabled) | ||
228 | |||
229 | Set the hardware to ignore all write/erase cycles to the GbE region in the | ||
230 | ICHx NVM (non-volatile memory). This feature can be disabled by the | ||
231 | WriteProtectNVM module parameter (enabled by default) only after a hardware | ||
232 | reset, but the machine must be power cycled before trying to enable writes. | ||
233 | |||
234 | Note: the kernel boot option iomem=relaxed may need to be set if the kernel | ||
235 | config option CONFIG_STRICT_DEVMEM=y, if the root user wants to write the | ||
236 | NVM from user space via ethtool. | ||
237 | |||
238 | Additional Configurations | ||
239 | ========================= | ||
240 | |||
241 | Jumbo Frames | ||
242 | ------------ | ||
243 | Jumbo Frames support is enabled by changing the MTU to a value larger than | ||
244 | the default of 1500. Use the ifconfig command to increase the MTU size. | ||
245 | For example: | ||
246 | |||
247 | ifconfig eth<x> mtu 9000 up | ||
248 | |||
249 | This setting is not saved across reboots. | ||
250 | |||
251 | Notes: | ||
252 | |||
253 | - The maximum MTU setting for Jumbo Frames is 9216. This value coincides | ||
254 | with the maximum Jumbo Frames size of 9234 bytes. | ||
255 | |||
256 | - Using Jumbo Frames at 10 or 100 Mbps is not supported and may result in | ||
257 | poor performance or loss of link. | ||
258 | |||
259 | - Some adapters limit Jumbo Frames sized packets to a maximum of | ||
260 | 4096 bytes and some adapters do not support Jumbo Frames. | ||
261 | |||
262 | |||
263 | Ethtool | ||
264 | ------- | ||
265 | The driver utilizes the ethtool interface for driver configuration and | ||
266 | diagnostics, as well as displaying statistical information. We | ||
267 | strongly recommend downloading the latest version of Ethtool at: | ||
268 | |||
269 | http://sourceforge.net/projects/gkernel. | ||
270 | |||
271 | Speed and Duplex | ||
272 | ---------------- | ||
273 | Speed and Duplex are configured through the Ethtool* utility. For | ||
274 | instructions, refer to the Ethtool man page. | ||
275 | |||
276 | Enabling Wake on LAN* (WoL) | ||
277 | --------------------------- | ||
278 | WoL is configured through the Ethtool* utility. For instructions on | ||
279 | enabling WoL with Ethtool, refer to the Ethtool man page. | ||
280 | |||
281 | WoL will be enabled on the system during the next shut down or reboot. | ||
282 | For this driver version, in order to enable WoL, the e1000e driver must be | ||
283 | loaded when shutting down or rebooting the system. | ||
284 | |||
285 | In most cases Wake On LAN is only supported on port A for multiple port | ||
286 | adapters. To verify if a port supports Wake on LAN run ethtool eth<X>. | ||
287 | |||
288 | |||
289 | Support | ||
290 | ======= | ||
291 | |||
292 | For general information, go to the Intel support website at: | ||
293 | |||
294 | www.intel.com/support/ | ||
295 | |||
296 | or the Intel Wired Networking project hosted by Sourceforge at: | ||
297 | |||
298 | http://sourceforge.net/projects/e1000 | ||
299 | |||
300 | If an issue is identified with the released source code on the supported | ||
301 | kernel with a supported adapter, email the specific information related | ||
302 | to the issue to e1000-devel@lists.sf.net | ||
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index f350c69b2bb4..c7165f4cb792 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt | |||
@@ -1014,6 +1014,12 @@ conf/interface/*: | |||
1014 | accept_ra - BOOLEAN | 1014 | accept_ra - BOOLEAN |
1015 | Accept Router Advertisements; autoconfigure using them. | 1015 | Accept Router Advertisements; autoconfigure using them. |
1016 | 1016 | ||
1017 | Possible values are: | ||
1018 | 0 Do not accept Router Advertisements. | ||
1019 | 1 Accept Router Advertisements if forwarding is disabled. | ||
1020 | 2 Overrule forwarding behaviour. Accept Router Advertisements | ||
1021 | even if forwarding is enabled. | ||
1022 | |||
1017 | Functional default: enabled if local forwarding is disabled. | 1023 | Functional default: enabled if local forwarding is disabled. |
1018 | disabled if local forwarding is enabled. | 1024 | disabled if local forwarding is enabled. |
1019 | 1025 | ||
@@ -1075,7 +1081,12 @@ forwarding - BOOLEAN | |||
1075 | Note: It is recommended to have the same setting on all | 1081 | Note: It is recommended to have the same setting on all |
1076 | interfaces; mixed router/host scenarios are rather uncommon. | 1082 | interfaces; mixed router/host scenarios are rather uncommon. |
1077 | 1083 | ||
1078 | FALSE: | 1084 | Possible values are: |
1085 | 0 Forwarding disabled | ||
1086 | 1 Forwarding enabled | ||
1087 | 2 Forwarding enabled (Hybrid Mode) | ||
1088 | |||
1089 | FALSE (0): | ||
1079 | 1090 | ||
1080 | By default, Host behaviour is assumed. This means: | 1091 | By default, Host behaviour is assumed. This means: |
1081 | 1092 | ||
@@ -1085,18 +1096,24 @@ forwarding - BOOLEAN | |||
1085 | Advertisements (and do autoconfiguration). | 1096 | Advertisements (and do autoconfiguration). |
1086 | 4. If accept_redirects is TRUE (default), accept Redirects. | 1097 | 4. If accept_redirects is TRUE (default), accept Redirects. |
1087 | 1098 | ||
1088 | TRUE: | 1099 | TRUE (1): |
1089 | 1100 | ||
1090 | If local forwarding is enabled, Router behaviour is assumed. | 1101 | If local forwarding is enabled, Router behaviour is assumed. |
1091 | This means exactly the reverse from the above: | 1102 | This means exactly the reverse from the above: |
1092 | 1103 | ||
1093 | 1. IsRouter flag is set in Neighbour Advertisements. | 1104 | 1. IsRouter flag is set in Neighbour Advertisements. |
1094 | 2. Router Solicitations are not sent. | 1105 | 2. Router Solicitations are not sent. |
1095 | 3. Router Advertisements are ignored. | 1106 | 3. Router Advertisements are ignored unless accept_ra is 2. |
1096 | 4. Redirects are ignored. | 1107 | 4. Redirects are ignored. |
1097 | 1108 | ||
1098 | Default: FALSE if global forwarding is disabled (default), | 1109 | TRUE (2): |
1099 | otherwise TRUE. | 1110 | |
1111 | Hybrid mode. Same behaviour as TRUE, except for: | ||
1112 | |||
1113 | 2. Router Solicitations are being sent when necessary. | ||
1114 | |||
1115 | Default: 0 (disabled) if global forwarding is disabled (default), | ||
1116 | otherwise 1 (enabled). | ||
1100 | 1117 | ||
1101 | hop_limit - INTEGER | 1118 | hop_limit - INTEGER |
1102 | Default Hop Limit to set. | 1119 | Default Hop Limit to set. |
diff --git a/Documentation/networking/ixgbevf.txt b/Documentation/networking/ixgbevf.txt index 19015de6725f..21dd5d15b6b4 100755..100644 --- a/Documentation/networking/ixgbevf.txt +++ b/Documentation/networking/ixgbevf.txt | |||
@@ -1,19 +1,16 @@ | |||
1 | Linux* Base Driver for Intel(R) Network Connection | 1 | Linux* Base Driver for Intel(R) Network Connection |
2 | ================================================== | 2 | ================================================== |
3 | 3 | ||
4 | November 24, 2009 | 4 | Intel Gigabit Linux driver. |
5 | Copyright(c) 1999 - 2010 Intel Corporation. | ||
5 | 6 | ||
6 | Contents | 7 | Contents |
7 | ======== | 8 | ======== |
8 | 9 | ||
9 | - In This Release | ||
10 | - Identifying Your Adapter | 10 | - Identifying Your Adapter |
11 | - Known Issues/Troubleshooting | 11 | - Known Issues/Troubleshooting |
12 | - Support | 12 | - Support |
13 | 13 | ||
14 | In This Release | ||
15 | =============== | ||
16 | |||
17 | This file describes the ixgbevf Linux* Base Driver for Intel Network | 14 | This file describes the ixgbevf Linux* Base Driver for Intel Network |
18 | Connection. | 15 | Connection. |
19 | 16 | ||
@@ -33,7 +30,7 @@ Identifying Your Adapter | |||
33 | For more information on how to identify your adapter, go to the Adapter & | 30 | For more information on how to identify your adapter, go to the Adapter & |
34 | Driver ID Guide at: | 31 | Driver ID Guide at: |
35 | 32 | ||
36 | http://support.intel.com/support/network/sb/CS-008441.htm | 33 | http://support.intel.com/support/go/network/adapter/idguide.htm |
37 | 34 | ||
38 | Known Issues/Troubleshooting | 35 | Known Issues/Troubleshooting |
39 | ============================ | 36 | ============================ |
@@ -57,34 +54,3 @@ or the Intel Wired Networking project hosted by Sourceforge at: | |||
57 | If an issue is identified with the released source code on the supported | 54 | If an issue is identified with the released source code on the supported |
58 | kernel with a supported adapter, email the specific information related | 55 | kernel with a supported adapter, email the specific information related |
59 | to the issue to e1000-devel@lists.sf.net | 56 | to the issue to e1000-devel@lists.sf.net |
60 | |||
61 | License | ||
62 | ======= | ||
63 | |||
64 | Intel 10 Gigabit Linux driver. | ||
65 | Copyright(c) 1999 - 2009 Intel Corporation. | ||
66 | |||
67 | This program is free software; you can redistribute it and/or modify it | ||
68 | under the terms and conditions of the GNU General Public License, | ||
69 | version 2, as published by the Free Software Foundation. | ||
70 | |||
71 | This program is distributed in the hope it will be useful, but WITHOUT | ||
72 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | ||
73 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | ||
74 | more details. | ||
75 | |||
76 | You should have received a copy of the GNU General Public License along with | ||
77 | this program; if not, write to the Free Software Foundation, Inc., | ||
78 | 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. | ||
79 | |||
80 | The full GNU General Public License is included in this distribution in | ||
81 | the file called "COPYING". | ||
82 | |||
83 | Trademarks | ||
84 | ========== | ||
85 | |||
86 | Intel, Itanium, and Pentium are trademarks or registered trademarks of | ||
87 | Intel Corporation or its subsidiaries in the United States and other | ||
88 | countries. | ||
89 | |||
90 | * Other names and brands may be claimed as the property of others. | ||
diff --git a/Documentation/networking/phonet.txt b/Documentation/networking/phonet.txt index 6e8ce09f9c73..24ad2adba6e5 100644 --- a/Documentation/networking/phonet.txt +++ b/Documentation/networking/phonet.txt | |||
@@ -112,6 +112,22 @@ However, connect() and getpeername() are not supported, as they did | |||
112 | not seem useful with Phonet usages (could be added easily). | 112 | not seem useful with Phonet usages (could be added easily). |
113 | 113 | ||
114 | 114 | ||
115 | Resource subscription | ||
116 | --------------------- | ||
117 | |||
118 | A Phonet datagram socket can be subscribed to any number of 8-bits | ||
119 | Phonet resources, as follow: | ||
120 | |||
121 | uint32_t res = 0xXX; | ||
122 | ioctl(fd, SIOCPNADDRESOURCE, &res); | ||
123 | |||
124 | Subscription is similarly cancelled using the SIOCPNDELRESOURCE I/O | ||
125 | control request, or when the socket is closed. | ||
126 | |||
127 | Note that no more than one socket can be subcribed to any given | ||
128 | resource at a time. If not, ioctl() will return EBUSY. | ||
129 | |||
130 | |||
115 | Phonet Pipe protocol | 131 | Phonet Pipe protocol |
116 | -------------------- | 132 | -------------------- |
117 | 133 | ||
@@ -166,6 +182,46 @@ The pipe protocol provides two socket options at the SOL_PNPIPE level: | |||
166 | or zero if encapsulation is off. | 182 | or zero if encapsulation is off. |
167 | 183 | ||
168 | 184 | ||
185 | Phonet Pipe-controller Implementation | ||
186 | ------------------------------------- | ||
187 | |||
188 | Phonet Pipe-controller is enabled by selecting the CONFIG_PHONET_PIPECTRLR Kconfig | ||
189 | option. It is useful when communicating with those Nokia Modems which do not | ||
190 | implement Pipe controller in them e.g. Nokia Slim Modem used in ST-Ericsson | ||
191 | U8500 platform. | ||
192 | |||
193 | The implementation is based on the Data Connection Establishment Sequence | ||
194 | depicted in 'Nokia Wireless Modem API - Wireless_modem_user_guide.pdf' | ||
195 | document. | ||
196 | |||
197 | It allows a phonet sequenced socket (host-pep) to initiate a Pipe connection | ||
198 | between itself and a remote pipe-end point (e.g. modem). | ||
199 | |||
200 | The implementation adds socket options at SOL_PNPIPE level: | ||
201 | |||
202 | PNPIPE_PIPE_HANDLE | ||
203 | It accepts an integer argument for setting value of pipe handle. | ||
204 | |||
205 | PNPIPE_ENABLE accepts one integer value (int). If set to zero, the pipe | ||
206 | is disabled. If the value is non-zero, the pipe is enabled. If the pipe | ||
207 | is not (yet) connected, ENOTCONN is error is returned. | ||
208 | |||
209 | The implementation also adds socket 'connect'. On calling the 'connect', pipe | ||
210 | will be created between the source socket and the destination, and the pipe | ||
211 | state will be set to PIPE_DISABLED. | ||
212 | |||
213 | After a pipe has been created and enabled successfully, the Pipe data can be | ||
214 | exchanged between the host-pep and remote-pep (modem). | ||
215 | |||
216 | User-space would typically follow below sequence with Pipe controller:- | ||
217 | -socket | ||
218 | -bind | ||
219 | -setsockopt for PNPIPE_PIPE_HANDLE | ||
220 | -connect | ||
221 | -setsockopt for PNPIPE_ENCAP_IP | ||
222 | -setsockopt for PNPIPE_ENABLE | ||
223 | |||
224 | |||
169 | Authors | 225 | Authors |
170 | ------- | 226 | ------- |
171 | 227 | ||
diff --git a/Documentation/networking/timestamping.txt b/Documentation/networking/timestamping.txt index e8c8f4f06c67..98097d8cb910 100644 --- a/Documentation/networking/timestamping.txt +++ b/Documentation/networking/timestamping.txt | |||
@@ -172,15 +172,19 @@ struct skb_shared_hwtstamps { | |||
172 | }; | 172 | }; |
173 | 173 | ||
174 | Time stamps for outgoing packets are to be generated as follows: | 174 | Time stamps for outgoing packets are to be generated as follows: |
175 | - In hard_start_xmit(), check if skb_tx(skb)->hardware is set no-zero. | 175 | - In hard_start_xmit(), check if (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) |
176 | If yes, then the driver is expected to do hardware time stamping. | 176 | is set no-zero. If yes, then the driver is expected to do hardware time |
177 | stamping. | ||
177 | - If this is possible for the skb and requested, then declare | 178 | - If this is possible for the skb and requested, then declare |
178 | that the driver is doing the time stamping by setting the field | 179 | that the driver is doing the time stamping by setting the flag |
179 | skb_tx(skb)->in_progress non-zero. You might want to keep a pointer | 180 | SKBTX_IN_PROGRESS in skb_shinfo(skb)->tx_flags , e.g. with |
180 | to the associated skb for the next step and not free the skb. A driver | 181 | |
181 | not supporting hardware time stamping doesn't do that. A driver must | 182 | skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS; |
182 | never touch sk_buff::tstamp! It is used to store software generated | 183 | |
183 | time stamps by the network subsystem. | 184 | You might want to keep a pointer to the associated skb for the next step |
185 | and not free the skb. A driver not supporting hardware time stamping doesn't | ||
186 | do that. A driver must never touch sk_buff::tstamp! It is used to store | ||
187 | software generated time stamps by the network subsystem. | ||
184 | - As soon as the driver has sent the packet and/or obtained a | 188 | - As soon as the driver has sent the packet and/or obtained a |
185 | hardware time stamp for it, it passes the time stamp back by | 189 | hardware time stamp for it, it passes the time stamp back by |
186 | calling skb_hwtstamp_tx() with the original skb, the raw | 190 | calling skb_hwtstamp_tx() with the original skb, the raw |
@@ -191,6 +195,6 @@ Time stamps for outgoing packets are to be generated as follows: | |||
191 | this would occur at a later time in the processing pipeline than other | 195 | this would occur at a later time in the processing pipeline than other |
192 | software time stamping and therefore could lead to unexpected deltas | 196 | software time stamping and therefore could lead to unexpected deltas |
193 | between time stamps. | 197 | between time stamps. |
194 | - If the driver did not call set skb_tx(skb)->in_progress, then | 198 | - If the driver did not set the SKBTX_IN_PROGRESS flag (see above), then |
195 | dev_hard_start_xmit() checks whether software time stamping | 199 | dev_hard_start_xmit() checks whether software time stamping |
196 | is wanted as fallback and potentially generates the time stamp. | 200 | is wanted as fallback and potentially generates the time stamp. |
diff --git a/Documentation/networking/wavelan.txt b/Documentation/networking/wavelan.txt deleted file mode 100644 index 90e0ac4e15da..000000000000 --- a/Documentation/networking/wavelan.txt +++ /dev/null | |||
@@ -1,74 +0,0 @@ | |||
1 | The Wavelan drivers saga | ||
2 | ------------------------ | ||
3 | |||
4 | By Jean Tourrilhes <jt@hpl.hp.com> | ||
5 | |||
6 | The Wavelan is a Radio network adapter designed by | ||
7 | Lucent. Under this generic name is hidden quite a variety of hardware, | ||
8 | and many Linux driver to support it. | ||
9 | The get the full story on Wireless LANs, please consult : | ||
10 | http://www.hpl.hp.com/personal/Jean_Tourrilhes/Linux/ | ||
11 | |||
12 | "wavelan" driver (old ISA Wavelan) | ||
13 | ---------------- | ||
14 | o Config : Network device -> Wireless LAN -> AT&T WaveLAN | ||
15 | o Location : .../drivers/net/wireless/wavelan* | ||
16 | o in-line doc : .../drivers/net/wireless/wavelan.p.h | ||
17 | o on-line doc : | ||
18 | http://www.hpl.hp.com/personal/Jean_Tourrilhes/Linux/Wavelan.html | ||
19 | |||
20 | This is the driver for the ISA version of the first generation | ||
21 | of the Wavelan, now discontinued. The device is 2 Mb/s, composed of a | ||
22 | Intel 82586 controller and a Lucent Modem, and is NOT 802.11 compliant. | ||
23 | The driver has been tested with the following hardware : | ||
24 | o Wavelan ISA 915 MHz (full length ISA card) | ||
25 | o Wavelan ISA 915 MHz 2.0 (half length ISA card) | ||
26 | o Wavelan ISA 2.4 GHz (full length ISA card, fixed frequency) | ||
27 | o Wavelan ISA 2.4 GHz 2.0 (half length ISA card, frequency selectable) | ||
28 | o Above cards with the optional DES encryption feature | ||
29 | |||
30 | "wavelan_cs" driver (old Pcmcia Wavelan) | ||
31 | ------------------- | ||
32 | o Config : Network device -> PCMCIA network -> | ||
33 | Pcmcia Wireless LAN -> AT&T/Lucent WaveLAN | ||
34 | o Location : .../drivers/net/pcmcia/wavelan* | ||
35 | o in-line doc : .../drivers/net/pcmcia/wavelan_cs.h | ||
36 | o on-line doc : | ||
37 | http://www.hpl.hp.com/personal/Jean_Tourrilhes/Linux/Wavelan.html | ||
38 | |||
39 | This is the driver for the PCMCIA version of the first | ||
40 | generation of the Wavelan, now discontinued. The device is 2 Mb/s, | ||
41 | composed of a Intel 82593 controller (totally different from the 82586) | ||
42 | and a Lucent Modem, and NOT 802.11 compatible. | ||
43 | The driver has been tested with the following hardware : | ||
44 | o Wavelan Pcmcia 915 MHz 2.0 (Pcmcia card + separate | ||
45 | modem/antenna block) | ||
46 | o Wavelan Pcmcia 2.4 GHz 2.0 (Pcmcia card + separate | ||
47 | modem/antenna block) | ||
48 | |||
49 | "wvlan_cs" driver (Wavelan IEEE, GPL) | ||
50 | ----------------- | ||
51 | o Config : Not yet in kernel | ||
52 | o Location : Pcmcia package 3.1.10+ | ||
53 | o on-line doc : | ||
54 | http://web.archive.org/web/*/http://www.fasta.fh-dortmund.de/users/andy/wvlan/ | ||
55 | |||
56 | This is the driver for the current generation of Wavelan IEEE, | ||
57 | which is 802.11 compatible. Depending on version, it is 2 Mb/s or 11 | ||
58 | Mb/s, with or without encryption, all implemented in Lucent specific | ||
59 | DSP (the Hermes). | ||
60 | This is a GPL full source PCMCIA driver (ISA is just a Pcmcia | ||
61 | card with ISA-Pcmcia bridge). | ||
62 | |||
63 | "wavelan2_cs" driver (Wavelan IEEE, binary) | ||
64 | -------------------- | ||
65 | o Config : Not yet in kernel | ||
66 | o Location : ftp://sourceforge.org/pcmcia/contrib/ | ||
67 | |||
68 | This driver support exactly the same hardware as the previous | ||
69 | driver, the main difference is that it is based on a binary library | ||
70 | and supported by Lucent. | ||
71 | |||
72 | I hope it clears the confusion ;-) | ||
73 | |||
74 | Jean | ||
diff --git a/Documentation/padata.txt b/Documentation/padata.txt index 473ebf22cd69..7ddfe216a0aa 100644 --- a/Documentation/padata.txt +++ b/Documentation/padata.txt | |||
@@ -19,7 +19,7 @@ overall control of how tasks are to be run: | |||
19 | 19 | ||
20 | The pcpumask describes which processors will be used to execute work | 20 | The pcpumask describes which processors will be used to execute work |
21 | submitted to this instance in parallel. The cbcpumask defines which | 21 | submitted to this instance in parallel. The cbcpumask defines which |
22 | processors are allowed to use as the serialization callback processor. | 22 | processors are allowed to be used as the serialization callback processor. |
23 | The workqueue wq is where the work will actually be done; it should be | 23 | The workqueue wq is where the work will actually be done; it should be |
24 | a multithreaded queue, naturally. | 24 | a multithreaded queue, naturally. |
25 | 25 | ||
@@ -30,10 +30,10 @@ cpumasks this helper function can be used: | |||
30 | 30 | ||
31 | Note: Padata maintains two kinds of cpumasks internally. The user supplied | 31 | Note: Padata maintains two kinds of cpumasks internally. The user supplied |
32 | cpumasks, submitted by padata_alloc/padata_alloc_possible and the 'usable' | 32 | cpumasks, submitted by padata_alloc/padata_alloc_possible and the 'usable' |
33 | cpumasks. The usable cpumasks are always the subset of active cpus in the | 33 | cpumasks. The usable cpumasks are always a subset of active CPUs in the |
34 | user supplied cpumasks, these are the cpumasks padata actually use. So | 34 | user supplied cpumasks; these are the cpumasks padata actually uses. So |
35 | it is legal to supply a cpumask to padata that contains offline cpus. | 35 | it is legal to supply a cpumask to padata that contains offline CPUs. |
36 | Once a offline cpu in the user supplied cpumask comes online, padata | 36 | Once an offline CPU in the user supplied cpumask comes online, padata |
37 | is going to use it. | 37 | is going to use it. |
38 | 38 | ||
39 | There are functions for enabling and disabling the instance: | 39 | There are functions for enabling and disabling the instance: |
@@ -44,7 +44,7 @@ There are functions for enabling and disabling the instance: | |||
44 | These functions are setting or clearing the "PADATA_INIT" flag; | 44 | These functions are setting or clearing the "PADATA_INIT" flag; |
45 | if that flag is not set, other functions will refuse to work. | 45 | if that flag is not set, other functions will refuse to work. |
46 | padata_start returns zero on success (flag set) or -EINVAL if the | 46 | padata_start returns zero on success (flag set) or -EINVAL if the |
47 | padata cpumask contains no active cpu (flag not set). | 47 | padata cpumask contains no active CPU (flag not set). |
48 | padata_stop clears the flag and blocks until the padata instance | 48 | padata_stop clears the flag and blocks until the padata instance |
49 | is unused. | 49 | is unused. |
50 | 50 | ||
@@ -63,11 +63,11 @@ done with great frequency. | |||
63 | 63 | ||
64 | It's possible to change both cpumasks of a padata instance with | 64 | It's possible to change both cpumasks of a padata instance with |
65 | padata_set_cpumasks by specifying the cpumasks for parallel execution (pcpumask) | 65 | padata_set_cpumasks by specifying the cpumasks for parallel execution (pcpumask) |
66 | and for the serial callback function (cbcpumask). padata_set_cpumask is to | 66 | and for the serial callback function (cbcpumask). padata_set_cpumask is used to |
67 | change just one of the cpumasks. Here cpumask_type is one of PADATA_CPU_SERIAL, | 67 | change just one of the cpumasks. Here cpumask_type is one of PADATA_CPU_SERIAL, |
68 | PADATA_CPU_PARALLEL and cpumask specifies the new cpumask to use. | 68 | PADATA_CPU_PARALLEL and cpumask specifies the new cpumask to use. |
69 | To simply add or remove one cpu from a certain cpumask the functions | 69 | To simply add or remove one CPU from a certain cpumask the functions |
70 | padata_add_cpu/padata_remove_cpu are used. cpu specifies the cpu to add or | 70 | padata_add_cpu/padata_remove_cpu are used. cpu specifies the CPU to add or |
71 | remove and mask is one of PADATA_CPU_SERIAL, PADATA_CPU_PARALLEL. | 71 | remove and mask is one of PADATA_CPU_SERIAL, PADATA_CPU_PARALLEL. |
72 | 72 | ||
73 | If a user is interested in padata cpumask changes, he can register to | 73 | If a user is interested in padata cpumask changes, he can register to |
@@ -82,7 +82,7 @@ To unregister from that notifier: | |||
82 | struct notifier_block *nblock); | 82 | struct notifier_block *nblock); |
83 | 83 | ||
84 | The padata cpumask change notifier notifies about changes of the usable | 84 | The padata cpumask change notifier notifies about changes of the usable |
85 | cpumasks, i.e. the subset of active cpus in the user supplied cpumask. | 85 | cpumasks, i.e. the subset of active CPUs in the user supplied cpumask. |
86 | 86 | ||
87 | Padata calls the notifier chain with: | 87 | Padata calls the notifier chain with: |
88 | 88 | ||
@@ -92,7 +92,7 @@ Padata calls the notifier chain with: | |||
92 | 92 | ||
93 | Here cpumask_change_notifier is registered notifier, notification_mask | 93 | Here cpumask_change_notifier is registered notifier, notification_mask |
94 | is one of PADATA_CPU_SERIAL, PADATA_CPU_PARALLEL and cpumask is a pointer | 94 | is one of PADATA_CPU_SERIAL, PADATA_CPU_PARALLEL and cpumask is a pointer |
95 | to a struct padata_cpumask that contains the new cpumask informations. | 95 | to a struct padata_cpumask that contains the new cpumask information. |
96 | 96 | ||
97 | Actually submitting work to the padata instance requires the creation of a | 97 | Actually submitting work to the padata instance requires the creation of a |
98 | padata_priv structure: | 98 | padata_priv structure: |
@@ -104,7 +104,7 @@ padata_priv structure: | |||
104 | }; | 104 | }; |
105 | 105 | ||
106 | This structure will almost certainly be embedded within some larger | 106 | This structure will almost certainly be embedded within some larger |
107 | structure specific to the work to be done. Most its fields are private to | 107 | structure specific to the work to be done. Most of its fields are private to |
108 | padata, but the structure should be zeroed at initialisation time, and the | 108 | padata, but the structure should be zeroed at initialisation time, and the |
109 | parallel() and serial() functions should be provided. Those functions will | 109 | parallel() and serial() functions should be provided. Those functions will |
110 | be called in the process of getting the work done as we will see | 110 | be called in the process of getting the work done as we will see |
diff --git a/Documentation/pcmcia/driver-changes.txt b/Documentation/pcmcia/driver-changes.txt index 26c0f9c00545..dd04361dd361 100644 --- a/Documentation/pcmcia/driver-changes.txt +++ b/Documentation/pcmcia/driver-changes.txt | |||
@@ -1,4 +1,29 @@ | |||
1 | This file details changes in 2.6 which affect PCMCIA card driver authors: | 1 | This file details changes in 2.6 which affect PCMCIA card driver authors: |
2 | * pcmcia_loop_config() and autoconfiguration (as of 2.6.36) | ||
3 | If struct pcmcia_device *p_dev->config_flags is set accordingly, | ||
4 | pcmcia_loop_config() now sets up certain configuration values | ||
5 | automatically, though the driver may still override the settings | ||
6 | in the callback function. The following autoconfiguration options | ||
7 | are provided at the moment: | ||
8 | CONF_AUTO_CHECK_VCC : check for matching Vcc | ||
9 | CONF_AUTO_SET_VPP : set Vpp | ||
10 | CONF_AUTO_AUDIO : auto-enable audio line, if required | ||
11 | CONF_AUTO_SET_IO : set ioport resources (->resource[0,1]) | ||
12 | CONF_AUTO_SET_IOMEM : set first iomem resource (->resource[2]) | ||
13 | |||
14 | * pcmcia_request_configuration -> pcmcia_enable_device (as of 2.6.36) | ||
15 | pcmcia_request_configuration() got renamed to pcmcia_enable_device(), | ||
16 | as it mirrors pcmcia_disable_device(). Configuration settings are now | ||
17 | stored in struct pcmcia_device, e.g. in the fields config_flags, | ||
18 | config_index, config_base, vpp. | ||
19 | |||
20 | * pcmcia_request_window changes (as of 2.6.36) | ||
21 | Instead of win_req_t, drivers are now requested to fill out | ||
22 | struct pcmcia_device *p_dev->resource[2,3,4,5] for up to four ioport | ||
23 | ranges. After a call to pcmcia_request_window(), the regions found there | ||
24 | are reserved and may be used immediately -- until pcmcia_release_window() | ||
25 | is called. | ||
26 | |||
2 | * pcmcia_request_io changes (as of 2.6.36) | 27 | * pcmcia_request_io changes (as of 2.6.36) |
3 | Instead of io_req_t, drivers are now requested to fill out | 28 | Instead of io_req_t, drivers are now requested to fill out |
4 | struct pcmcia_device *p_dev->resource[0,1] for up to two ioport | 29 | struct pcmcia_device *p_dev->resource[0,1] for up to two ioport |
diff --git a/Documentation/power/00-INDEX b/Documentation/power/00-INDEX index fb742c213c9e..45e9d4a91284 100644 --- a/Documentation/power/00-INDEX +++ b/Documentation/power/00-INDEX | |||
@@ -14,6 +14,8 @@ interface.txt | |||
14 | - Power management user interface in /sys/power | 14 | - Power management user interface in /sys/power |
15 | notifiers.txt | 15 | notifiers.txt |
16 | - Registering suspend notifiers in device drivers | 16 | - Registering suspend notifiers in device drivers |
17 | opp.txt | ||
18 | - Operating Performance Point library | ||
17 | pci.txt | 19 | pci.txt |
18 | - How the PCI Subsystem Does Power Management | 20 | - How the PCI Subsystem Does Power Management |
19 | pm_qos_interface.txt | 21 | pm_qos_interface.txt |
diff --git a/Documentation/power/interface.txt b/Documentation/power/interface.txt index e67211fe0ee2..c537834af005 100644 --- a/Documentation/power/interface.txt +++ b/Documentation/power/interface.txt | |||
@@ -57,7 +57,7 @@ smallest image possible. In particular, if "0" is written to this file, the | |||
57 | suspend image will be as small as possible. | 57 | suspend image will be as small as possible. |
58 | 58 | ||
59 | Reading from this file will display the current image size limit, which | 59 | Reading from this file will display the current image size limit, which |
60 | is set to 500 MB by default. | 60 | is set to 2/5 of available RAM by default. |
61 | 61 | ||
62 | /sys/power/pm_trace controls the code which saves the last PM event point in | 62 | /sys/power/pm_trace controls the code which saves the last PM event point in |
63 | the RTC across reboots, so that you can debug a machine that just hangs | 63 | the RTC across reboots, so that you can debug a machine that just hangs |
diff --git a/Documentation/power/opp.txt b/Documentation/power/opp.txt new file mode 100644 index 000000000000..44d87ad3cea9 --- /dev/null +++ b/Documentation/power/opp.txt | |||
@@ -0,0 +1,375 @@ | |||
1 | *=============* | ||
2 | * OPP Library * | ||
3 | *=============* | ||
4 | |||
5 | (C) 2009-2010 Nishanth Menon <nm@ti.com>, Texas Instruments Incorporated | ||
6 | |||
7 | Contents | ||
8 | -------- | ||
9 | 1. Introduction | ||
10 | 2. Initial OPP List Registration | ||
11 | 3. OPP Search Functions | ||
12 | 4. OPP Availability Control Functions | ||
13 | 5. OPP Data Retrieval Functions | ||
14 | 6. Cpufreq Table Generation | ||
15 | 7. Data Structures | ||
16 | |||
17 | 1. Introduction | ||
18 | =============== | ||
19 | Complex SoCs of today consists of a multiple sub-modules working in conjunction. | ||
20 | In an operational system executing varied use cases, not all modules in the SoC | ||
21 | need to function at their highest performing frequency all the time. To | ||
22 | facilitate this, sub-modules in a SoC are grouped into domains, allowing some | ||
23 | domains to run at lower voltage and frequency while other domains are loaded | ||
24 | more. The set of discrete tuples consisting of frequency and voltage pairs that | ||
25 | the device will support per domain are called Operating Performance Points or | ||
26 | OPPs. | ||
27 | |||
28 | OPP library provides a set of helper functions to organize and query the OPP | ||
29 | information. The library is located in drivers/base/power/opp.c and the header | ||
30 | is located in include/linux/opp.h. OPP library can be enabled by enabling | ||
31 | CONFIG_PM_OPP from power management menuconfig menu. OPP library depends on | ||
32 | CONFIG_PM as certain SoCs such as Texas Instrument's OMAP framework allows to | ||
33 | optionally boot at a certain OPP without needing cpufreq. | ||
34 | |||
35 | Typical usage of the OPP library is as follows: | ||
36 | (users) -> registers a set of default OPPs -> (library) | ||
37 | SoC framework -> modifies on required cases certain OPPs -> OPP layer | ||
38 | -> queries to search/retrieve information -> | ||
39 | |||
40 | OPP layer expects each domain to be represented by a unique device pointer. SoC | ||
41 | framework registers a set of initial OPPs per device with the OPP layer. This | ||
42 | list is expected to be an optimally small number typically around 5 per device. | ||
43 | This initial list contains a set of OPPs that the framework expects to be safely | ||
44 | enabled by default in the system. | ||
45 | |||
46 | Note on OPP Availability: | ||
47 | ------------------------ | ||
48 | As the system proceeds to operate, SoC framework may choose to make certain | ||
49 | OPPs available or not available on each device based on various external | ||
50 | factors. Example usage: Thermal management or other exceptional situations where | ||
51 | SoC framework might choose to disable a higher frequency OPP to safely continue | ||
52 | operations until that OPP could be re-enabled if possible. | ||
53 | |||
54 | OPP library facilitates this concept in it's implementation. The following | ||
55 | operational functions operate only on available opps: | ||
56 | opp_find_freq_{ceil, floor}, opp_get_voltage, opp_get_freq, opp_get_opp_count | ||
57 | and opp_init_cpufreq_table | ||
58 | |||
59 | opp_find_freq_exact is meant to be used to find the opp pointer which can then | ||
60 | be used for opp_enable/disable functions to make an opp available as required. | ||
61 | |||
62 | WARNING: Users of OPP library should refresh their availability count using | ||
63 | get_opp_count if opp_enable/disable functions are invoked for a device, the | ||
64 | exact mechanism to trigger these or the notification mechanism to other | ||
65 | dependent subsystems such as cpufreq are left to the discretion of the SoC | ||
66 | specific framework which uses the OPP library. Similar care needs to be taken | ||
67 | care to refresh the cpufreq table in cases of these operations. | ||
68 | |||
69 | WARNING on OPP List locking mechanism: | ||
70 | ------------------------------------------------- | ||
71 | OPP library uses RCU for exclusivity. RCU allows the query functions to operate | ||
72 | in multiple contexts and this synchronization mechanism is optimal for a read | ||
73 | intensive operations on data structure as the OPP library caters to. | ||
74 | |||
75 | To ensure that the data retrieved are sane, the users such as SoC framework | ||
76 | should ensure that the section of code operating on OPP queries are locked | ||
77 | using RCU read locks. The opp_find_freq_{exact,ceil,floor}, | ||
78 | opp_get_{voltage, freq, opp_count} fall into this category. | ||
79 | |||
80 | opp_{add,enable,disable} are updaters which use mutex and implement it's own | ||
81 | RCU locking mechanisms. opp_init_cpufreq_table acts as an updater and uses | ||
82 | mutex to implment RCU updater strategy. These functions should *NOT* be called | ||
83 | under RCU locks and other contexts that prevent blocking functions in RCU or | ||
84 | mutex operations from working. | ||
85 | |||
86 | 2. Initial OPP List Registration | ||
87 | ================================ | ||
88 | The SoC implementation calls opp_add function iteratively to add OPPs per | ||
89 | device. It is expected that the SoC framework will register the OPP entries | ||
90 | optimally- typical numbers range to be less than 5. The list generated by | ||
91 | registering the OPPs is maintained by OPP library throughout the device | ||
92 | operation. The SoC framework can subsequently control the availability of the | ||
93 | OPPs dynamically using the opp_enable / disable functions. | ||
94 | |||
95 | opp_add - Add a new OPP for a specific domain represented by the device pointer. | ||
96 | The OPP is defined using the frequency and voltage. Once added, the OPP | ||
97 | is assumed to be available and control of it's availability can be done | ||
98 | with the opp_enable/disable functions. OPP library internally stores | ||
99 | and manages this information in the opp struct. This function may be | ||
100 | used by SoC framework to define a optimal list as per the demands of | ||
101 | SoC usage environment. | ||
102 | |||
103 | WARNING: Do not use this function in interrupt context. | ||
104 | |||
105 | Example: | ||
106 | soc_pm_init() | ||
107 | { | ||
108 | /* Do things */ | ||
109 | r = opp_add(mpu_dev, 1000000, 900000); | ||
110 | if (!r) { | ||
111 | pr_err("%s: unable to register mpu opp(%d)\n", r); | ||
112 | goto no_cpufreq; | ||
113 | } | ||
114 | /* Do cpufreq things */ | ||
115 | no_cpufreq: | ||
116 | /* Do remaining things */ | ||
117 | } | ||
118 | |||
119 | 3. OPP Search Functions | ||
120 | ======================= | ||
121 | High level framework such as cpufreq operates on frequencies. To map the | ||
122 | frequency back to the corresponding OPP, OPP library provides handy functions | ||
123 | to search the OPP list that OPP library internally manages. These search | ||
124 | functions return the matching pointer representing the opp if a match is | ||
125 | found, else returns error. These errors are expected to be handled by standard | ||
126 | error checks such as IS_ERR() and appropriate actions taken by the caller. | ||
127 | |||
128 | opp_find_freq_exact - Search for an OPP based on an *exact* frequency and | ||
129 | availability. This function is especially useful to enable an OPP which | ||
130 | is not available by default. | ||
131 | Example: In a case when SoC framework detects a situation where a | ||
132 | higher frequency could be made available, it can use this function to | ||
133 | find the OPP prior to call the opp_enable to actually make it available. | ||
134 | rcu_read_lock(); | ||
135 | opp = opp_find_freq_exact(dev, 1000000000, false); | ||
136 | rcu_read_unlock(); | ||
137 | /* dont operate on the pointer.. just do a sanity check.. */ | ||
138 | if (IS_ERR(opp)) { | ||
139 | pr_err("frequency not disabled!\n"); | ||
140 | /* trigger appropriate actions.. */ | ||
141 | } else { | ||
142 | opp_enable(dev,1000000000); | ||
143 | } | ||
144 | |||
145 | NOTE: This is the only search function that operates on OPPs which are | ||
146 | not available. | ||
147 | |||
148 | opp_find_freq_floor - Search for an available OPP which is *at most* the | ||
149 | provided frequency. This function is useful while searching for a lesser | ||
150 | match OR operating on OPP information in the order of decreasing | ||
151 | frequency. | ||
152 | Example: To find the highest opp for a device: | ||
153 | freq = ULONG_MAX; | ||
154 | rcu_read_lock(); | ||
155 | opp_find_freq_floor(dev, &freq); | ||
156 | rcu_read_unlock(); | ||
157 | |||
158 | opp_find_freq_ceil - Search for an available OPP which is *at least* the | ||
159 | provided frequency. This function is useful while searching for a | ||
160 | higher match OR operating on OPP information in the order of increasing | ||
161 | frequency. | ||
162 | Example 1: To find the lowest opp for a device: | ||
163 | freq = 0; | ||
164 | rcu_read_lock(); | ||
165 | opp_find_freq_ceil(dev, &freq); | ||
166 | rcu_read_unlock(); | ||
167 | Example 2: A simplified implementation of a SoC cpufreq_driver->target: | ||
168 | soc_cpufreq_target(..) | ||
169 | { | ||
170 | /* Do stuff like policy checks etc. */ | ||
171 | /* Find the best frequency match for the req */ | ||
172 | rcu_read_lock(); | ||
173 | opp = opp_find_freq_ceil(dev, &freq); | ||
174 | rcu_read_unlock(); | ||
175 | if (!IS_ERR(opp)) | ||
176 | soc_switch_to_freq_voltage(freq); | ||
177 | else | ||
178 | /* do something when we cant satisfy the req */ | ||
179 | /* do other stuff */ | ||
180 | } | ||
181 | |||
182 | 4. OPP Availability Control Functions | ||
183 | ===================================== | ||
184 | A default OPP list registered with the OPP library may not cater to all possible | ||
185 | situation. The OPP library provides a set of functions to modify the | ||
186 | availability of a OPP within the OPP list. This allows SoC frameworks to have | ||
187 | fine grained dynamic control of which sets of OPPs are operationally available. | ||
188 | These functions are intended to *temporarily* remove an OPP in conditions such | ||
189 | as thermal considerations (e.g. don't use OPPx until the temperature drops). | ||
190 | |||
191 | WARNING: Do not use these functions in interrupt context. | ||
192 | |||
193 | opp_enable - Make a OPP available for operation. | ||
194 | Example: Lets say that 1GHz OPP is to be made available only if the | ||
195 | SoC temperature is lower than a certain threshold. The SoC framework | ||
196 | implementation might choose to do something as follows: | ||
197 | if (cur_temp < temp_low_thresh) { | ||
198 | /* Enable 1GHz if it was disabled */ | ||
199 | rcu_read_lock(); | ||
200 | opp = opp_find_freq_exact(dev, 1000000000, false); | ||
201 | rcu_read_unlock(); | ||
202 | /* just error check */ | ||
203 | if (!IS_ERR(opp)) | ||
204 | ret = opp_enable(dev, 1000000000); | ||
205 | else | ||
206 | goto try_something_else; | ||
207 | } | ||
208 | |||
209 | opp_disable - Make an OPP to be not available for operation | ||
210 | Example: Lets say that 1GHz OPP is to be disabled if the temperature | ||
211 | exceeds a threshold value. The SoC framework implementation might | ||
212 | choose to do something as follows: | ||
213 | if (cur_temp > temp_high_thresh) { | ||
214 | /* Disable 1GHz if it was enabled */ | ||
215 | rcu_read_lock(); | ||
216 | opp = opp_find_freq_exact(dev, 1000000000, true); | ||
217 | rcu_read_unlock(); | ||
218 | /* just error check */ | ||
219 | if (!IS_ERR(opp)) | ||
220 | ret = opp_disable(dev, 1000000000); | ||
221 | else | ||
222 | goto try_something_else; | ||
223 | } | ||
224 | |||
225 | 5. OPP Data Retrieval Functions | ||
226 | =============================== | ||
227 | Since OPP library abstracts away the OPP information, a set of functions to pull | ||
228 | information from the OPP structure is necessary. Once an OPP pointer is | ||
229 | retrieved using the search functions, the following functions can be used by SoC | ||
230 | framework to retrieve the information represented inside the OPP layer. | ||
231 | |||
232 | opp_get_voltage - Retrieve the voltage represented by the opp pointer. | ||
233 | Example: At a cpufreq transition to a different frequency, SoC | ||
234 | framework requires to set the voltage represented by the OPP using | ||
235 | the regulator framework to the Power Management chip providing the | ||
236 | voltage. | ||
237 | soc_switch_to_freq_voltage(freq) | ||
238 | { | ||
239 | /* do things */ | ||
240 | rcu_read_lock(); | ||
241 | opp = opp_find_freq_ceil(dev, &freq); | ||
242 | v = opp_get_voltage(opp); | ||
243 | rcu_read_unlock(); | ||
244 | if (v) | ||
245 | regulator_set_voltage(.., v); | ||
246 | /* do other things */ | ||
247 | } | ||
248 | |||
249 | opp_get_freq - Retrieve the freq represented by the opp pointer. | ||
250 | Example: Lets say the SoC framework uses a couple of helper functions | ||
251 | we could pass opp pointers instead of doing additional parameters to | ||
252 | handle quiet a bit of data parameters. | ||
253 | soc_cpufreq_target(..) | ||
254 | { | ||
255 | /* do things.. */ | ||
256 | max_freq = ULONG_MAX; | ||
257 | rcu_read_lock(); | ||
258 | max_opp = opp_find_freq_floor(dev,&max_freq); | ||
259 | requested_opp = opp_find_freq_ceil(dev,&freq); | ||
260 | if (!IS_ERR(max_opp) && !IS_ERR(requested_opp)) | ||
261 | r = soc_test_validity(max_opp, requested_opp); | ||
262 | rcu_read_unlock(); | ||
263 | /* do other things */ | ||
264 | } | ||
265 | soc_test_validity(..) | ||
266 | { | ||
267 | if(opp_get_voltage(max_opp) < opp_get_voltage(requested_opp)) | ||
268 | return -EINVAL; | ||
269 | if(opp_get_freq(max_opp) < opp_get_freq(requested_opp)) | ||
270 | return -EINVAL; | ||
271 | /* do things.. */ | ||
272 | } | ||
273 | |||
274 | opp_get_opp_count - Retrieve the number of available opps for a device | ||
275 | Example: Lets say a co-processor in the SoC needs to know the available | ||
276 | frequencies in a table, the main processor can notify as following: | ||
277 | soc_notify_coproc_available_frequencies() | ||
278 | { | ||
279 | /* Do things */ | ||
280 | rcu_read_lock(); | ||
281 | num_available = opp_get_opp_count(dev); | ||
282 | speeds = kzalloc(sizeof(u32) * num_available, GFP_KERNEL); | ||
283 | /* populate the table in increasing order */ | ||
284 | freq = 0; | ||
285 | while (!IS_ERR(opp = opp_find_freq_ceil(dev, &freq))) { | ||
286 | speeds[i] = freq; | ||
287 | freq++; | ||
288 | i++; | ||
289 | } | ||
290 | rcu_read_unlock(); | ||
291 | |||
292 | soc_notify_coproc(AVAILABLE_FREQs, speeds, num_available); | ||
293 | /* Do other things */ | ||
294 | } | ||
295 | |||
296 | 6. Cpufreq Table Generation | ||
297 | =========================== | ||
298 | opp_init_cpufreq_table - cpufreq framework typically is initialized with | ||
299 | cpufreq_frequency_table_cpuinfo which is provided with the list of | ||
300 | frequencies that are available for operation. This function provides | ||
301 | a ready to use conversion routine to translate the OPP layer's internal | ||
302 | information about the available frequencies into a format readily | ||
303 | providable to cpufreq. | ||
304 | |||
305 | WARNING: Do not use this function in interrupt context. | ||
306 | |||
307 | Example: | ||
308 | soc_pm_init() | ||
309 | { | ||
310 | /* Do things */ | ||
311 | r = opp_init_cpufreq_table(dev, &freq_table); | ||
312 | if (!r) | ||
313 | cpufreq_frequency_table_cpuinfo(policy, freq_table); | ||
314 | /* Do other things */ | ||
315 | } | ||
316 | |||
317 | NOTE: This function is available only if CONFIG_CPU_FREQ is enabled in | ||
318 | addition to CONFIG_PM as power management feature is required to | ||
319 | dynamically scale voltage and frequency in a system. | ||
320 | |||
321 | 7. Data Structures | ||
322 | ================== | ||
323 | Typically an SoC contains multiple voltage domains which are variable. Each | ||
324 | domain is represented by a device pointer. The relationship to OPP can be | ||
325 | represented as follows: | ||
326 | SoC | ||
327 | |- device 1 | ||
328 | | |- opp 1 (availability, freq, voltage) | ||
329 | | |- opp 2 .. | ||
330 | ... ... | ||
331 | | `- opp n .. | ||
332 | |- device 2 | ||
333 | ... | ||
334 | `- device m | ||
335 | |||
336 | OPP library maintains a internal list that the SoC framework populates and | ||
337 | accessed by various functions as described above. However, the structures | ||
338 | representing the actual OPPs and domains are internal to the OPP library itself | ||
339 | to allow for suitable abstraction reusable across systems. | ||
340 | |||
341 | struct opp - The internal data structure of OPP library which is used to | ||
342 | represent an OPP. In addition to the freq, voltage, availability | ||
343 | information, it also contains internal book keeping information required | ||
344 | for the OPP library to operate on. Pointer to this structure is | ||
345 | provided back to the users such as SoC framework to be used as a | ||
346 | identifier for OPP in the interactions with OPP layer. | ||
347 | |||
348 | WARNING: The struct opp pointer should not be parsed or modified by the | ||
349 | users. The defaults of for an instance is populated by opp_add, but the | ||
350 | availability of the OPP can be modified by opp_enable/disable functions. | ||
351 | |||
352 | struct device - This is used to identify a domain to the OPP layer. The | ||
353 | nature of the device and it's implementation is left to the user of | ||
354 | OPP library such as the SoC framework. | ||
355 | |||
356 | Overall, in a simplistic view, the data structure operations is represented as | ||
357 | following: | ||
358 | |||
359 | Initialization / modification: | ||
360 | +-----+ /- opp_enable | ||
361 | opp_add --> | opp | <------- | ||
362 | | +-----+ \- opp_disable | ||
363 | \-------> domain_info(device) | ||
364 | |||
365 | Search functions: | ||
366 | /-- opp_find_freq_ceil ---\ +-----+ | ||
367 | domain_info<---- opp_find_freq_exact -----> | opp | | ||
368 | \-- opp_find_freq_floor ---/ +-----+ | ||
369 | |||
370 | Retrieval functions: | ||
371 | +-----+ /- opp_get_voltage | ||
372 | | opp | <--- | ||
373 | +-----+ \- opp_get_freq | ||
374 | |||
375 | domain_info <- opp_get_opp_count | ||
diff --git a/Documentation/power/regulator/overview.txt b/Documentation/power/regulator/overview.txt index 9363e056188a..8ed17587a74b 100644 --- a/Documentation/power/regulator/overview.txt +++ b/Documentation/power/regulator/overview.txt | |||
@@ -13,7 +13,7 @@ regulators (where voltage output is controllable) and current sinks (where | |||
13 | current limit is controllable). | 13 | current limit is controllable). |
14 | 14 | ||
15 | (C) 2008 Wolfson Microelectronics PLC. | 15 | (C) 2008 Wolfson Microelectronics PLC. |
16 | Author: Liam Girdwood <lg@opensource.wolfsonmicro.com> | 16 | Author: Liam Girdwood <lrg@slimlogic.co.uk> |
17 | 17 | ||
18 | 18 | ||
19 | Nomenclature | 19 | Nomenclature |
diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index 55b859b3bc72..489e9bacd165 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt | |||
@@ -1,6 +1,7 @@ | |||
1 | Run-time Power Management Framework for I/O Devices | 1 | Run-time Power Management Framework for I/O Devices |
2 | 2 | ||
3 | (C) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. | 3 | (C) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. |
4 | (C) 2010 Alan Stern <stern@rowland.harvard.edu> | ||
4 | 5 | ||
5 | 1. Introduction | 6 | 1. Introduction |
6 | 7 | ||
@@ -157,7 +158,8 @@ rules: | |||
157 | to execute it, the other callbacks will not be executed for the same device. | 158 | to execute it, the other callbacks will not be executed for the same device. |
158 | 159 | ||
159 | * A request to execute ->runtime_resume() will cancel any pending or | 160 | * A request to execute ->runtime_resume() will cancel any pending or |
160 | scheduled requests to execute the other callbacks for the same device. | 161 | scheduled requests to execute the other callbacks for the same device, |
162 | except for scheduled autosuspends. | ||
161 | 163 | ||
162 | 3. Run-time PM Device Fields | 164 | 3. Run-time PM Device Fields |
163 | 165 | ||
@@ -165,7 +167,7 @@ The following device run-time PM fields are present in 'struct dev_pm_info', as | |||
165 | defined in include/linux/pm.h: | 167 | defined in include/linux/pm.h: |
166 | 168 | ||
167 | struct timer_list suspend_timer; | 169 | struct timer_list suspend_timer; |
168 | - timer used for scheduling (delayed) suspend request | 170 | - timer used for scheduling (delayed) suspend and autosuspend requests |
169 | 171 | ||
170 | unsigned long timer_expires; | 172 | unsigned long timer_expires; |
171 | - timer expiration time, in jiffies (if this is different from zero, the | 173 | - timer expiration time, in jiffies (if this is different from zero, the |
@@ -230,6 +232,28 @@ defined in include/linux/pm.h: | |||
230 | interface; it may only be modified with the help of the pm_runtime_allow() | 232 | interface; it may only be modified with the help of the pm_runtime_allow() |
231 | and pm_runtime_forbid() helper functions | 233 | and pm_runtime_forbid() helper functions |
232 | 234 | ||
235 | unsigned int no_callbacks; | ||
236 | - indicates that the device does not use the run-time PM callbacks (see | ||
237 | Section 8); it may be modified only by the pm_runtime_no_callbacks() | ||
238 | helper function | ||
239 | |||
240 | unsigned int use_autosuspend; | ||
241 | - indicates that the device's driver supports delayed autosuspend (see | ||
242 | Section 9); it may be modified only by the | ||
243 | pm_runtime{_dont}_use_autosuspend() helper functions | ||
244 | |||
245 | unsigned int timer_autosuspends; | ||
246 | - indicates that the PM core should attempt to carry out an autosuspend | ||
247 | when the timer expires rather than a normal suspend | ||
248 | |||
249 | int autosuspend_delay; | ||
250 | - the delay time (in milliseconds) to be used for autosuspend | ||
251 | |||
252 | unsigned long last_busy; | ||
253 | - the time (in jiffies) when the pm_runtime_mark_last_busy() helper | ||
254 | function was last called for this device; used in calculating inactivity | ||
255 | periods for autosuspend | ||
256 | |||
233 | All of the above fields are members of the 'power' member of 'struct device'. | 257 | All of the above fields are members of the 'power' member of 'struct device'. |
234 | 258 | ||
235 | 4. Run-time PM Device Helper Functions | 259 | 4. Run-time PM Device Helper Functions |
@@ -255,6 +279,12 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: | |||
255 | error code on failure, where -EAGAIN or -EBUSY means it is safe to attempt | 279 | error code on failure, where -EAGAIN or -EBUSY means it is safe to attempt |
256 | to suspend the device again in future | 280 | to suspend the device again in future |
257 | 281 | ||
282 | int pm_runtime_autosuspend(struct device *dev); | ||
283 | - same as pm_runtime_suspend() except that the autosuspend delay is taken | ||
284 | into account; if pm_runtime_autosuspend_expiration() says the delay has | ||
285 | not yet expired then an autosuspend is scheduled for the appropriate time | ||
286 | and 0 is returned | ||
287 | |||
258 | int pm_runtime_resume(struct device *dev); | 288 | int pm_runtime_resume(struct device *dev); |
259 | - execute the subsystem-level resume callback for the device; returns 0 on | 289 | - execute the subsystem-level resume callback for the device; returns 0 on |
260 | success, 1 if the device's run-time PM status was already 'active' or | 290 | success, 1 if the device's run-time PM status was already 'active' or |
@@ -267,6 +297,11 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: | |||
267 | device (the request is represented by a work item in pm_wq); returns 0 on | 297 | device (the request is represented by a work item in pm_wq); returns 0 on |
268 | success or error code if the request has not been queued up | 298 | success or error code if the request has not been queued up |
269 | 299 | ||
300 | int pm_request_autosuspend(struct device *dev); | ||
301 | - schedule the execution of the subsystem-level suspend callback for the | ||
302 | device when the autosuspend delay has expired; if the delay has already | ||
303 | expired then the work item is queued up immediately | ||
304 | |||
270 | int pm_schedule_suspend(struct device *dev, unsigned int delay); | 305 | int pm_schedule_suspend(struct device *dev, unsigned int delay); |
271 | - schedule the execution of the subsystem-level suspend callback for the | 306 | - schedule the execution of the subsystem-level suspend callback for the |
272 | device in future, where 'delay' is the time to wait before queuing up a | 307 | device in future, where 'delay' is the time to wait before queuing up a |
@@ -298,12 +333,20 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: | |||
298 | - decrement the device's usage counter | 333 | - decrement the device's usage counter |
299 | 334 | ||
300 | int pm_runtime_put(struct device *dev); | 335 | int pm_runtime_put(struct device *dev); |
301 | - decrement the device's usage counter, run pm_request_idle(dev) and return | 336 | - decrement the device's usage counter; if the result is 0 then run |
302 | its result | 337 | pm_request_idle(dev) and return its result |
338 | |||
339 | int pm_runtime_put_autosuspend(struct device *dev); | ||
340 | - decrement the device's usage counter; if the result is 0 then run | ||
341 | pm_request_autosuspend(dev) and return its result | ||
303 | 342 | ||
304 | int pm_runtime_put_sync(struct device *dev); | 343 | int pm_runtime_put_sync(struct device *dev); |
305 | - decrement the device's usage counter, run pm_runtime_idle(dev) and return | 344 | - decrement the device's usage counter; if the result is 0 then run |
306 | its result | 345 | pm_runtime_idle(dev) and return its result |
346 | |||
347 | int pm_runtime_put_sync_autosuspend(struct device *dev); | ||
348 | - decrement the device's usage counter; if the result is 0 then run | ||
349 | pm_runtime_autosuspend(dev) and return its result | ||
307 | 350 | ||
308 | void pm_runtime_enable(struct device *dev); | 351 | void pm_runtime_enable(struct device *dev); |
309 | - enable the run-time PM helper functions to run the device bus type's | 352 | - enable the run-time PM helper functions to run the device bus type's |
@@ -349,19 +392,51 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: | |||
349 | counter (used by the /sys/devices/.../power/control interface to | 392 | counter (used by the /sys/devices/.../power/control interface to |
350 | effectively prevent the device from being power managed at run time) | 393 | effectively prevent the device from being power managed at run time) |
351 | 394 | ||
395 | void pm_runtime_no_callbacks(struct device *dev); | ||
396 | - set the power.no_callbacks flag for the device and remove the run-time | ||
397 | PM attributes from /sys/devices/.../power (or prevent them from being | ||
398 | added when the device is registered) | ||
399 | |||
400 | void pm_runtime_mark_last_busy(struct device *dev); | ||
401 | - set the power.last_busy field to the current time | ||
402 | |||
403 | void pm_runtime_use_autosuspend(struct device *dev); | ||
404 | - set the power.use_autosuspend flag, enabling autosuspend delays | ||
405 | |||
406 | void pm_runtime_dont_use_autosuspend(struct device *dev); | ||
407 | - clear the power.use_autosuspend flag, disabling autosuspend delays | ||
408 | |||
409 | void pm_runtime_set_autosuspend_delay(struct device *dev, int delay); | ||
410 | - set the power.autosuspend_delay value to 'delay' (expressed in | ||
411 | milliseconds); if 'delay' is negative then run-time suspends are | ||
412 | prevented | ||
413 | |||
414 | unsigned long pm_runtime_autosuspend_expiration(struct device *dev); | ||
415 | - calculate the time when the current autosuspend delay period will expire, | ||
416 | based on power.last_busy and power.autosuspend_delay; if the delay time | ||
417 | is 1000 ms or larger then the expiration time is rounded up to the | ||
418 | nearest second; returns 0 if the delay period has already expired or | ||
419 | power.use_autosuspend isn't set, otherwise returns the expiration time | ||
420 | in jiffies | ||
421 | |||
352 | It is safe to execute the following helper functions from interrupt context: | 422 | It is safe to execute the following helper functions from interrupt context: |
353 | 423 | ||
354 | pm_request_idle() | 424 | pm_request_idle() |
425 | pm_request_autosuspend() | ||
355 | pm_schedule_suspend() | 426 | pm_schedule_suspend() |
356 | pm_request_resume() | 427 | pm_request_resume() |
357 | pm_runtime_get_noresume() | 428 | pm_runtime_get_noresume() |
358 | pm_runtime_get() | 429 | pm_runtime_get() |
359 | pm_runtime_put_noidle() | 430 | pm_runtime_put_noidle() |
360 | pm_runtime_put() | 431 | pm_runtime_put() |
432 | pm_runtime_put_autosuspend() | ||
433 | pm_runtime_enable() | ||
361 | pm_suspend_ignore_children() | 434 | pm_suspend_ignore_children() |
362 | pm_runtime_set_active() | 435 | pm_runtime_set_active() |
363 | pm_runtime_set_suspended() | 436 | pm_runtime_set_suspended() |
364 | pm_runtime_enable() | 437 | pm_runtime_suspended() |
438 | pm_runtime_mark_last_busy() | ||
439 | pm_runtime_autosuspend_expiration() | ||
365 | 440 | ||
366 | 5. Run-time PM Initialization, Device Probing and Removal | 441 | 5. Run-time PM Initialization, Device Probing and Removal |
367 | 442 | ||
@@ -524,3 +599,141 @@ poweroff and run-time suspend callback, and similarly for system resume, thaw, | |||
524 | restore, and run-time resume, can achieve this with the help of the | 599 | restore, and run-time resume, can achieve this with the help of the |
525 | UNIVERSAL_DEV_PM_OPS macro defined in include/linux/pm.h (possibly setting its | 600 | UNIVERSAL_DEV_PM_OPS macro defined in include/linux/pm.h (possibly setting its |
526 | last argument to NULL). | 601 | last argument to NULL). |
602 | |||
603 | 8. "No-Callback" Devices | ||
604 | |||
605 | Some "devices" are only logical sub-devices of their parent and cannot be | ||
606 | power-managed on their own. (The prototype example is a USB interface. Entire | ||
607 | USB devices can go into low-power mode or send wake-up requests, but neither is | ||
608 | possible for individual interfaces.) The drivers for these devices have no | ||
609 | need of run-time PM callbacks; if the callbacks did exist, ->runtime_suspend() | ||
610 | and ->runtime_resume() would always return 0 without doing anything else and | ||
611 | ->runtime_idle() would always call pm_runtime_suspend(). | ||
612 | |||
613 | Subsystems can tell the PM core about these devices by calling | ||
614 | pm_runtime_no_callbacks(). This should be done after the device structure is | ||
615 | initialized and before it is registered (although after device registration is | ||
616 | also okay). The routine will set the device's power.no_callbacks flag and | ||
617 | prevent the non-debugging run-time PM sysfs attributes from being created. | ||
618 | |||
619 | When power.no_callbacks is set, the PM core will not invoke the | ||
620 | ->runtime_idle(), ->runtime_suspend(), or ->runtime_resume() callbacks. | ||
621 | Instead it will assume that suspends and resumes always succeed and that idle | ||
622 | devices should be suspended. | ||
623 | |||
624 | As a consequence, the PM core will never directly inform the device's subsystem | ||
625 | or driver about run-time power changes. Instead, the driver for the device's | ||
626 | parent must take responsibility for telling the device's driver when the | ||
627 | parent's power state changes. | ||
628 | |||
629 | 9. Autosuspend, or automatically-delayed suspends | ||
630 | |||
631 | Changing a device's power state isn't free; it requires both time and energy. | ||
632 | A device should be put in a low-power state only when there's some reason to | ||
633 | think it will remain in that state for a substantial time. A common heuristic | ||
634 | says that a device which hasn't been used for a while is liable to remain | ||
635 | unused; following this advice, drivers should not allow devices to be suspended | ||
636 | at run-time until they have been inactive for some minimum period. Even when | ||
637 | the heuristic ends up being non-optimal, it will still prevent devices from | ||
638 | "bouncing" too rapidly between low-power and full-power states. | ||
639 | |||
640 | The term "autosuspend" is an historical remnant. It doesn't mean that the | ||
641 | device is automatically suspended (the subsystem or driver still has to call | ||
642 | the appropriate PM routines); rather it means that run-time suspends will | ||
643 | automatically be delayed until the desired period of inactivity has elapsed. | ||
644 | |||
645 | Inactivity is determined based on the power.last_busy field. Drivers should | ||
646 | call pm_runtime_mark_last_busy() to update this field after carrying out I/O, | ||
647 | typically just before calling pm_runtime_put_autosuspend(). The desired length | ||
648 | of the inactivity period is a matter of policy. Subsystems can set this length | ||
649 | initially by calling pm_runtime_set_autosuspend_delay(), but after device | ||
650 | registration the length should be controlled by user space, using the | ||
651 | /sys/devices/.../power/autosuspend_delay_ms attribute. | ||
652 | |||
653 | In order to use autosuspend, subsystems or drivers must call | ||
654 | pm_runtime_use_autosuspend() (preferably before registering the device), and | ||
655 | thereafter they should use the various *_autosuspend() helper functions instead | ||
656 | of the non-autosuspend counterparts: | ||
657 | |||
658 | Instead of: pm_runtime_suspend use: pm_runtime_autosuspend; | ||
659 | Instead of: pm_schedule_suspend use: pm_request_autosuspend; | ||
660 | Instead of: pm_runtime_put use: pm_runtime_put_autosuspend; | ||
661 | Instead of: pm_runtime_put_sync use: pm_runtime_put_sync_autosuspend. | ||
662 | |||
663 | Drivers may also continue to use the non-autosuspend helper functions; they | ||
664 | will behave normally, not taking the autosuspend delay into account. | ||
665 | Similarly, if the power.use_autosuspend field isn't set then the autosuspend | ||
666 | helper functions will behave just like the non-autosuspend counterparts. | ||
667 | |||
668 | The implementation is well suited for asynchronous use in interrupt contexts. | ||
669 | However such use inevitably involves races, because the PM core can't | ||
670 | synchronize ->runtime_suspend() callbacks with the arrival of I/O requests. | ||
671 | This synchronization must be handled by the driver, using its private lock. | ||
672 | Here is a schematic pseudo-code example: | ||
673 | |||
674 | foo_read_or_write(struct foo_priv *foo, void *data) | ||
675 | { | ||
676 | lock(&foo->private_lock); | ||
677 | add_request_to_io_queue(foo, data); | ||
678 | if (foo->num_pending_requests++ == 0) | ||
679 | pm_runtime_get(&foo->dev); | ||
680 | if (!foo->is_suspended) | ||
681 | foo_process_next_request(foo); | ||
682 | unlock(&foo->private_lock); | ||
683 | } | ||
684 | |||
685 | foo_io_completion(struct foo_priv *foo, void *req) | ||
686 | { | ||
687 | lock(&foo->private_lock); | ||
688 | if (--foo->num_pending_requests == 0) { | ||
689 | pm_runtime_mark_last_busy(&foo->dev); | ||
690 | pm_runtime_put_autosuspend(&foo->dev); | ||
691 | } else { | ||
692 | foo_process_next_request(foo); | ||
693 | } | ||
694 | unlock(&foo->private_lock); | ||
695 | /* Send req result back to the user ... */ | ||
696 | } | ||
697 | |||
698 | int foo_runtime_suspend(struct device *dev) | ||
699 | { | ||
700 | struct foo_priv foo = container_of(dev, ...); | ||
701 | int ret = 0; | ||
702 | |||
703 | lock(&foo->private_lock); | ||
704 | if (foo->num_pending_requests > 0) { | ||
705 | ret = -EBUSY; | ||
706 | } else { | ||
707 | /* ... suspend the device ... */ | ||
708 | foo->is_suspended = 1; | ||
709 | } | ||
710 | unlock(&foo->private_lock); | ||
711 | return ret; | ||
712 | } | ||
713 | |||
714 | int foo_runtime_resume(struct device *dev) | ||
715 | { | ||
716 | struct foo_priv foo = container_of(dev, ...); | ||
717 | |||
718 | lock(&foo->private_lock); | ||
719 | /* ... resume the device ... */ | ||
720 | foo->is_suspended = 0; | ||
721 | pm_runtime_mark_last_busy(&foo->dev); | ||
722 | if (foo->num_pending_requests > 0) | ||
723 | foo_process_requests(foo); | ||
724 | unlock(&foo->private_lock); | ||
725 | return 0; | ||
726 | } | ||
727 | |||
728 | The important point is that after foo_io_completion() asks for an autosuspend, | ||
729 | the foo_runtime_suspend() callback may race with foo_read_or_write(). | ||
730 | Therefore foo_runtime_suspend() has to check whether there are any pending I/O | ||
731 | requests (while holding the private lock) before allowing the suspend to | ||
732 | proceed. | ||
733 | |||
734 | In addition, the power.autosuspend_delay field can be changed by user space at | ||
735 | any time. If a driver cares about this, it can call | ||
736 | pm_runtime_autosuspend_expiration() from within the ->runtime_suspend() | ||
737 | callback while holding its private lock. If the function returns a nonzero | ||
738 | value then the delay has not yet expired and the callback should return | ||
739 | -EAGAIN. | ||
diff --git a/Documentation/power/s2ram.txt b/Documentation/power/s2ram.txt index 514b94fc931e..1bdfa0443773 100644 --- a/Documentation/power/s2ram.txt +++ b/Documentation/power/s2ram.txt | |||
@@ -49,6 +49,13 @@ machine that doesn't boot) is: | |||
49 | device (lspci and /sys/devices/pci* is your friend), and see if you can | 49 | device (lspci and /sys/devices/pci* is your friend), and see if you can |
50 | fix it, disable it, or trace into its resume function. | 50 | fix it, disable it, or trace into its resume function. |
51 | 51 | ||
52 | If no device matches the hash (or any matches appear to be false positives), | ||
53 | the culprit may be a device from a loadable kernel module that is not loaded | ||
54 | until after the hash is checked. You can check the hash against the current | ||
55 | devices again after more modules are loaded using sysfs: | ||
56 | |||
57 | cat /sys/power/pm_trace_dev_match | ||
58 | |||
52 | For example, the above happens to be the VGA device on my EVO, which I | 59 | For example, the above happens to be the VGA device on my EVO, which I |
53 | used to run with "radeonfb" (it's an ATI Radeon mobility). It turns out | 60 | used to run with "radeonfb" (it's an ATI Radeon mobility). It turns out |
54 | that "radeonfb" simply cannot resume that device - it tries to set the | 61 | that "radeonfb" simply cannot resume that device - it tries to set the |
diff --git a/Documentation/power/swsusp.txt b/Documentation/power/swsusp.txt index 9d60ab717a7b..ea718891a665 100644 --- a/Documentation/power/swsusp.txt +++ b/Documentation/power/swsusp.txt | |||
@@ -66,7 +66,8 @@ swsusp saves the state of the machine into active swaps and then reboots or | |||
66 | powerdowns. You must explicitly specify the swap partition to resume from with | 66 | powerdowns. You must explicitly specify the swap partition to resume from with |
67 | ``resume='' kernel option. If signature is found it loads and restores saved | 67 | ``resume='' kernel option. If signature is found it loads and restores saved |
68 | state. If the option ``noresume'' is specified as a boot parameter, it skips | 68 | state. If the option ``noresume'' is specified as a boot parameter, it skips |
69 | the resuming. | 69 | the resuming. If the option ``hibernate=nocompress'' is specified as a boot |
70 | parameter, it saves hibernation image without compression. | ||
70 | 71 | ||
71 | In the meantime while the system is suspended you should not add/remove any | 72 | In the meantime while the system is suspended you should not add/remove any |
72 | of the hardware, write to the filesystems, etc. | 73 | of the hardware, write to the filesystems, etc. |
diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt index 568fa08e82e5..302db5da49b3 100644 --- a/Documentation/powerpc/booting-without-of.txt +++ b/Documentation/powerpc/booting-without-of.txt | |||
@@ -49,40 +49,13 @@ Table of Contents | |||
49 | f) MDIO on GPIOs | 49 | f) MDIO on GPIOs |
50 | g) SPI busses | 50 | g) SPI busses |
51 | 51 | ||
52 | VII - Marvell Discovery mv64[345]6x System Controller chips | 52 | VII - Specifying interrupt information for devices |
53 | 1) The /system-controller node | ||
54 | 2) Child nodes of /system-controller | ||
55 | a) Marvell Discovery MDIO bus | ||
56 | b) Marvell Discovery ethernet controller | ||
57 | c) Marvell Discovery PHY nodes | ||
58 | d) Marvell Discovery SDMA nodes | ||
59 | e) Marvell Discovery BRG nodes | ||
60 | f) Marvell Discovery CUNIT nodes | ||
61 | g) Marvell Discovery MPSCROUTING nodes | ||
62 | h) Marvell Discovery MPSCINTR nodes | ||
63 | i) Marvell Discovery MPSC nodes | ||
64 | j) Marvell Discovery Watch Dog Timer nodes | ||
65 | k) Marvell Discovery I2C nodes | ||
66 | l) Marvell Discovery PIC (Programmable Interrupt Controller) nodes | ||
67 | m) Marvell Discovery MPP (Multipurpose Pins) multiplexing nodes | ||
68 | n) Marvell Discovery GPP (General Purpose Pins) nodes | ||
69 | o) Marvell Discovery PCI host bridge node | ||
70 | p) Marvell Discovery CPU Error nodes | ||
71 | q) Marvell Discovery SRAM Controller nodes | ||
72 | r) Marvell Discovery PCI Error Handler nodes | ||
73 | s) Marvell Discovery Memory Controller nodes | ||
74 | |||
75 | VIII - Specifying interrupt information for devices | ||
76 | 1) interrupts property | 53 | 1) interrupts property |
77 | 2) interrupt-parent property | 54 | 2) interrupt-parent property |
78 | 3) OpenPIC Interrupt Controllers | 55 | 3) OpenPIC Interrupt Controllers |
79 | 4) ISA Interrupt Controllers | 56 | 4) ISA Interrupt Controllers |
80 | 57 | ||
81 | IX - Specifying GPIO information for devices | 58 | VIII - Specifying device power management information (sleep property) |
82 | 1) gpios property | ||
83 | 2) gpio-controller nodes | ||
84 | |||
85 | X - Specifying device power management information (sleep property) | ||
86 | 59 | ||
87 | Appendix A - Sample SOC node for MPC8540 | 60 | Appendix A - Sample SOC node for MPC8540 |
88 | 61 | ||
diff --git a/Documentation/powerpc/dts-bindings/fsl/esdhc.txt b/Documentation/powerpc/dts-bindings/fsl/esdhc.txt index 8a0040738969..64bcb8be973c 100644 --- a/Documentation/powerpc/dts-bindings/fsl/esdhc.txt +++ b/Documentation/powerpc/dts-bindings/fsl/esdhc.txt | |||
@@ -14,6 +14,8 @@ Required properties: | |||
14 | reports inverted write-protect state; | 14 | reports inverted write-protect state; |
15 | - sdhci,1-bit-only : (optional) specifies that a controller can | 15 | - sdhci,1-bit-only : (optional) specifies that a controller can |
16 | only handle 1-bit data transfers. | 16 | only handle 1-bit data transfers. |
17 | - sdhci,auto-cmd12: (optional) specifies that a controller can | ||
18 | only handle auto CMD12. | ||
17 | 19 | ||
18 | Example: | 20 | Example: |
19 | 21 | ||
diff --git a/Documentation/powerpc/dts-bindings/fsl/spi.txt b/Documentation/powerpc/dts-bindings/fsl/spi.txt index 80510c018eea..777abd7399d5 100644 --- a/Documentation/powerpc/dts-bindings/fsl/spi.txt +++ b/Documentation/powerpc/dts-bindings/fsl/spi.txt | |||
@@ -1,7 +1,9 @@ | |||
1 | * SPI (Serial Peripheral Interface) | 1 | * SPI (Serial Peripheral Interface) |
2 | 2 | ||
3 | Required properties: | 3 | Required properties: |
4 | - cell-index : SPI controller index. | 4 | - cell-index : QE SPI subblock index. |
5 | 0: QE subblock SPI1 | ||
6 | 1: QE subblock SPI2 | ||
5 | - compatible : should be "fsl,spi". | 7 | - compatible : should be "fsl,spi". |
6 | - mode : the SPI operation mode, it can be "cpu" or "cpu-qe". | 8 | - mode : the SPI operation mode, it can be "cpu" or "cpu-qe". |
7 | - reg : Offset and length of the register set for the device | 9 | - reg : Offset and length of the register set for the device |
@@ -29,3 +31,23 @@ Example: | |||
29 | gpios = <&gpio 18 1 // device reg=<0> | 31 | gpios = <&gpio 18 1 // device reg=<0> |
30 | &gpio 19 1>; // device reg=<1> | 32 | &gpio 19 1>; // device reg=<1> |
31 | }; | 33 | }; |
34 | |||
35 | |||
36 | * eSPI (Enhanced Serial Peripheral Interface) | ||
37 | |||
38 | Required properties: | ||
39 | - compatible : should be "fsl,mpc8536-espi". | ||
40 | - reg : Offset and length of the register set for the device. | ||
41 | - interrupts : should contain eSPI interrupt, the device has one interrupt. | ||
42 | - fsl,espi-num-chipselects : the number of the chipselect signals. | ||
43 | |||
44 | Example: | ||
45 | spi@110000 { | ||
46 | #address-cells = <1>; | ||
47 | #size-cells = <0>; | ||
48 | compatible = "fsl,mpc8536-espi"; | ||
49 | reg = <0x110000 0x1000>; | ||
50 | interrupts = <53 0x2>; | ||
51 | interrupt-parent = <&mpic>; | ||
52 | fsl,espi-num-chipselects = <4>; | ||
53 | }; | ||
diff --git a/Documentation/powerpc/dts-bindings/fsl/usb.txt b/Documentation/powerpc/dts-bindings/fsl/usb.txt index b00152402694..bd5723f0b67e 100644 --- a/Documentation/powerpc/dts-bindings/fsl/usb.txt +++ b/Documentation/powerpc/dts-bindings/fsl/usb.txt | |||
@@ -8,6 +8,7 @@ and additions : | |||
8 | Required properties : | 8 | Required properties : |
9 | - compatible : Should be "fsl-usb2-mph" for multi port host USB | 9 | - compatible : Should be "fsl-usb2-mph" for multi port host USB |
10 | controllers, or "fsl-usb2-dr" for dual role USB controllers | 10 | controllers, or "fsl-usb2-dr" for dual role USB controllers |
11 | or "fsl,mpc5121-usb2-dr" for dual role USB controllers of MPC5121 | ||
11 | - phy_type : For multi port host USB controllers, should be one of | 12 | - phy_type : For multi port host USB controllers, should be one of |
12 | "ulpi", or "serial". For dual role USB controllers, should be | 13 | "ulpi", or "serial". For dual role USB controllers, should be |
13 | one of "ulpi", "utmi", "utmi_wide", or "serial". | 14 | one of "ulpi", "utmi", "utmi_wide", or "serial". |
@@ -33,6 +34,12 @@ Recommended properties : | |||
33 | - interrupt-parent : the phandle for the interrupt controller that | 34 | - interrupt-parent : the phandle for the interrupt controller that |
34 | services interrupts for this device. | 35 | services interrupts for this device. |
35 | 36 | ||
37 | Optional properties : | ||
38 | - fsl,invert-drvvbus : boolean; for MPC5121 USB0 only. Indicates the | ||
39 | port power polarity of internal PHY signal DRVVBUS is inverted. | ||
40 | - fsl,invert-pwr-fault : boolean; for MPC5121 USB0 only. Indicates | ||
41 | the PWR_FAULT signal polarity is inverted. | ||
42 | |||
36 | Example multi port host USB controller device node : | 43 | Example multi port host USB controller device node : |
37 | usb@22000 { | 44 | usb@22000 { |
38 | compatible = "fsl-usb2-mph"; | 45 | compatible = "fsl-usb2-mph"; |
@@ -57,3 +64,18 @@ Example dual role USB controller device node : | |||
57 | dr_mode = "otg"; | 64 | dr_mode = "otg"; |
58 | phy = "ulpi"; | 65 | phy = "ulpi"; |
59 | }; | 66 | }; |
67 | |||
68 | Example dual role USB controller device node for MPC5121ADS: | ||
69 | |||
70 | usb@4000 { | ||
71 | compatible = "fsl,mpc5121-usb2-dr"; | ||
72 | reg = <0x4000 0x1000>; | ||
73 | #address-cells = <1>; | ||
74 | #size-cells = <0>; | ||
75 | interrupt-parent = < &ipic >; | ||
76 | interrupts = <44 0x8>; | ||
77 | dr_mode = "otg"; | ||
78 | phy_type = "utmi_wide"; | ||
79 | fsl,invert-drvvbus; | ||
80 | fsl,invert-pwr-fault; | ||
81 | }; | ||
diff --git a/Documentation/powerpc/hvcs.txt b/Documentation/powerpc/hvcs.txt index f93462c5db25..6d8be3468d7d 100644 --- a/Documentation/powerpc/hvcs.txt +++ b/Documentation/powerpc/hvcs.txt | |||
@@ -560,7 +560,7 @@ The proper channel for reporting bugs is either through the Linux OS | |||
560 | distribution company that provided your OS or by posting issues to the | 560 | distribution company that provided your OS or by posting issues to the |
561 | PowerPC development mailing list at: | 561 | PowerPC development mailing list at: |
562 | 562 | ||
563 | linuxppc-dev@ozlabs.org | 563 | linuxppc-dev@lists.ozlabs.org |
564 | 564 | ||
565 | This request is to provide a documented and searchable public exchange | 565 | This request is to provide a documented and searchable public exchange |
566 | of the problems and solutions surrounding this driver for the benefit of | 566 | of the problems and solutions surrounding this driver for the benefit of |
diff --git a/Documentation/scsi/scsi-parameters.txt b/Documentation/scsi/scsi-parameters.txt new file mode 100644 index 000000000000..21e5798526ee --- /dev/null +++ b/Documentation/scsi/scsi-parameters.txt | |||
@@ -0,0 +1,139 @@ | |||
1 | SCSI Kernel Parameters | ||
2 | ~~~~~~~~~~~~~~~~~~~~~~ | ||
3 | |||
4 | See Documentation/kernel-parameters.txt for general information on | ||
5 | specifying module parameters. | ||
6 | |||
7 | This document may not be entirely up to date and comprehensive. The command | ||
8 | "modinfo -p ${modulename}" shows a current list of all parameters of a loadable | ||
9 | module. Loadable modules, after being loaded into the running kernel, also | ||
10 | reveal their parameters in /sys/module/${modulename}/parameters/. Some of these | ||
11 | parameters may be changed at runtime by the command | ||
12 | "echo -n ${value} > /sys/module/${modulename}/parameters/${parm}". | ||
13 | |||
14 | |||
15 | advansys= [HW,SCSI] | ||
16 | See header of drivers/scsi/advansys.c. | ||
17 | |||
18 | aha152x= [HW,SCSI] | ||
19 | See Documentation/scsi/aha152x.txt. | ||
20 | |||
21 | aha1542= [HW,SCSI] | ||
22 | Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]] | ||
23 | |||
24 | aic7xxx= [HW,SCSI] | ||
25 | See Documentation/scsi/aic7xxx.txt. | ||
26 | |||
27 | aic79xx= [HW,SCSI] | ||
28 | See Documentation/scsi/aic79xx.txt. | ||
29 | |||
30 | atascsi= [HW,SCSI] Atari SCSI | ||
31 | |||
32 | BusLogic= [HW,SCSI] | ||
33 | See drivers/scsi/BusLogic.c, comment before function | ||
34 | BusLogic_ParseDriverOptions(). | ||
35 | |||
36 | dtc3181e= [HW,SCSI] | ||
37 | |||
38 | eata= [HW,SCSI] | ||
39 | |||
40 | fd_mcs= [HW,SCSI] | ||
41 | See header of drivers/scsi/fd_mcs.c. | ||
42 | |||
43 | fdomain= [HW,SCSI] | ||
44 | See header of drivers/scsi/fdomain.c. | ||
45 | |||
46 | gdth= [HW,SCSI] | ||
47 | See header of drivers/scsi/gdth.c. | ||
48 | |||
49 | gvp11= [HW,SCSI] | ||
50 | |||
51 | ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter | ||
52 | See Documentation/mca.txt. | ||
53 | |||
54 | in2000= [HW,SCSI] | ||
55 | See header of drivers/scsi/in2000.c. | ||
56 | |||
57 | ips= [HW,SCSI] Adaptec / IBM ServeRAID controller | ||
58 | See header of drivers/scsi/ips.c. | ||
59 | |||
60 | mac5380= [HW,SCSI] Format: | ||
61 | <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags> | ||
62 | |||
63 | max_luns= [SCSI] Maximum number of LUNs to probe. | ||
64 | Should be between 1 and 2^32-1. | ||
65 | |||
66 | max_report_luns= | ||
67 | [SCSI] Maximum number of LUNs received. | ||
68 | Should be between 1 and 16384. | ||
69 | |||
70 | NCR_D700= [HW,SCSI] | ||
71 | See header of drivers/scsi/NCR_D700.c. | ||
72 | |||
73 | ncr5380= [HW,SCSI] | ||
74 | |||
75 | ncr53c400= [HW,SCSI] | ||
76 | |||
77 | ncr53c400a= [HW,SCSI] | ||
78 | |||
79 | ncr53c406a= [HW,SCSI] | ||
80 | |||
81 | ncr53c8xx= [HW,SCSI] | ||
82 | |||
83 | nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects. | ||
84 | |||
85 | osst= [HW,SCSI] SCSI Tape Driver | ||
86 | Format: <buffer_size>,<write_threshold> | ||
87 | See also Documentation/scsi/st.txt. | ||
88 | |||
89 | pas16= [HW,SCSI] | ||
90 | See header of drivers/scsi/pas16.c. | ||
91 | |||
92 | scsi_debug_*= [SCSI] | ||
93 | See drivers/scsi/scsi_debug.c. | ||
94 | |||
95 | scsi_default_dev_flags= | ||
96 | [SCSI] SCSI default device flags | ||
97 | Format: <integer> | ||
98 | |||
99 | scsi_dev_flags= [SCSI] Black/white list entry for vendor and model | ||
100 | Format: <vendor>:<model>:<flags> | ||
101 | (flags are integer value) | ||
102 | |||
103 | scsi_logging_level= [SCSI] a bit mask of logging levels | ||
104 | See drivers/scsi/scsi_logging.h for bits. Also | ||
105 | settable via sysctl at dev.scsi.logging_level | ||
106 | (/proc/sys/dev/scsi/logging_level). | ||
107 | There is also a nice 'scsi_logging_level' script in the | ||
108 | S390-tools package, available for download at | ||
109 | http://www-128.ibm.com/developerworks/linux/linux390/s390-tools-1.5.4.html | ||
110 | |||
111 | scsi_mod.scan= [SCSI] sync (default) scans SCSI busses as they are | ||
112 | discovered. async scans them in kernel threads, | ||
113 | allowing boot to proceed. none ignores them, expecting | ||
114 | user space to do the scan. | ||
115 | |||
116 | sim710= [SCSI,HW] | ||
117 | See header of drivers/scsi/sim710.c. | ||
118 | |||
119 | st= [HW,SCSI] SCSI tape parameters (buffers, etc.) | ||
120 | See Documentation/scsi/st.txt. | ||
121 | |||
122 | sym53c416= [HW,SCSI] | ||
123 | See header of drivers/scsi/sym53c416.c. | ||
124 | |||
125 | t128= [HW,SCSI] | ||
126 | See header of drivers/scsi/t128.c. | ||
127 | |||
128 | tmscsim= [HW,SCSI] | ||
129 | See comment before function dc390_setup() in | ||
130 | drivers/scsi/tmscsim.c. | ||
131 | |||
132 | u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter | ||
133 | See header of drivers/scsi/u14-34f.c. | ||
134 | |||
135 | wd33c93= [HW,SCSI] | ||
136 | See header of drivers/scsi/wd33c93.c. | ||
137 | |||
138 | wd7000= [HW,SCSI] | ||
139 | See header of drivers/scsi/wd7000.c. | ||
diff --git a/Documentation/scsi/st.txt b/Documentation/scsi/st.txt index 40752602c050..691ca292c24d 100644 --- a/Documentation/scsi/st.txt +++ b/Documentation/scsi/st.txt | |||
@@ -2,7 +2,7 @@ This file contains brief information about the SCSI tape driver. | |||
2 | The driver is currently maintained by Kai Mäkisara (email | 2 | The driver is currently maintained by Kai Mäkisara (email |
3 | Kai.Makisara@kolumbus.fi) | 3 | Kai.Makisara@kolumbus.fi) |
4 | 4 | ||
5 | Last modified: Sun Feb 24 21:59:07 2008 by kai.makisara | 5 | Last modified: Sun Aug 29 18:25:47 2010 by kai.makisara |
6 | 6 | ||
7 | 7 | ||
8 | BASICS | 8 | BASICS |
@@ -85,6 +85,17 @@ writing and the last operation has been a write. Two filemarks can be | |||
85 | optionally written. In both cases end of data is signified by | 85 | optionally written. In both cases end of data is signified by |
86 | returning zero bytes for two consecutive reads. | 86 | returning zero bytes for two consecutive reads. |
87 | 87 | ||
88 | Writing filemarks without the immediate bit set in the SCSI command block acts | ||
89 | as a synchronization point, i.e., all remaining data form the drive buffers is | ||
90 | written to tape before the command returns. This makes sure that write errors | ||
91 | are caught at that point, but this takes time. In some applications, several | ||
92 | consecutive files must be written fast. The MTWEOFI operation can be used to | ||
93 | write the filemarks without flushing the drive buffer. Writing filemark at | ||
94 | close() is always flushing the drive buffers. However, if the previous | ||
95 | operation is MTWEOFI, close() does not write a filemark. This can be used if | ||
96 | the program wants to close/open the tape device between files and wants to | ||
97 | skip waiting. | ||
98 | |||
88 | If rewind, offline, bsf, or seek is done and previous tape operation was | 99 | If rewind, offline, bsf, or seek is done and previous tape operation was |
89 | write, a filemark is written before moving tape. | 100 | write, a filemark is written before moving tape. |
90 | 101 | ||
@@ -301,6 +312,8 @@ MTBSR Space backward over count records. | |||
301 | MTFSS Space forward over count setmarks. | 312 | MTFSS Space forward over count setmarks. |
302 | MTBSS Space backward over count setmarks. | 313 | MTBSS Space backward over count setmarks. |
303 | MTWEOF Write count filemarks. | 314 | MTWEOF Write count filemarks. |
315 | MTWEOFI Write count filemarks with immediate bit set (i.e., does not | ||
316 | wait until data is on tape) | ||
304 | MTWSM Write count setmarks. | 317 | MTWSM Write count setmarks. |
305 | MTREW Rewind tape. | 318 | MTREW Rewind tape. |
306 | MTOFFL Set device off line (often rewind plus eject). | 319 | MTOFFL Set device off line (often rewind plus eject). |
diff --git a/Documentation/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt index 03771d7c5dd7..37c6aad5e590 100644 --- a/Documentation/sound/alsa/HD-Audio-Models.txt +++ b/Documentation/sound/alsa/HD-Audio-Models.txt | |||
@@ -83,8 +83,8 @@ ALC269 | |||
83 | ====== | 83 | ====== |
84 | basic Basic preset | 84 | basic Basic preset |
85 | quanta Quanta FL1 | 85 | quanta Quanta FL1 |
86 | eeepc-p703 ASUS Eeepc P703 P900A | 86 | laptop-amic Laptops with analog-mic input |
87 | eeepc-p901 ASUS Eeepc P901 S101 | 87 | laptop-dmic Laptops with digital-mic input |
88 | fujitsu FSC Amilo | 88 | fujitsu FSC Amilo |
89 | lifebook Fujitsu Lifebook S6420 | 89 | lifebook Fujitsu Lifebook S6420 |
90 | auto auto-config reading BIOS (default) | 90 | auto auto-config reading BIOS (default) |
@@ -109,6 +109,8 @@ ALC662/663/272 | |||
109 | asus-mode4 ASUS | 109 | asus-mode4 ASUS |
110 | asus-mode5 ASUS | 110 | asus-mode5 ASUS |
111 | asus-mode6 ASUS | 111 | asus-mode6 ASUS |
112 | asus-mode7 ASUS | ||
113 | asus-mode8 ASUS | ||
112 | dell Dell with ALC272 | 114 | dell Dell with ALC272 |
113 | dell-zm1 Dell ZM1 with ALC272 | 115 | dell-zm1 Dell ZM1 with ALC272 |
114 | samsung-nc10 Samsung NC10 mini notebook | 116 | samsung-nc10 Samsung NC10 mini notebook |
@@ -294,9 +296,12 @@ Conexant 5051 | |||
294 | Conexant 5066 | 296 | Conexant 5066 |
295 | ============= | 297 | ============= |
296 | laptop Basic Laptop config (default) | 298 | laptop Basic Laptop config (default) |
299 | hp-laptop HP laptops, e g G60 | ||
297 | dell-laptop Dell laptops | 300 | dell-laptop Dell laptops |
301 | dell-vostro Dell Vostro | ||
298 | olpc-xo-1_5 OLPC XO 1.5 | 302 | olpc-xo-1_5 OLPC XO 1.5 |
299 | ideapad Lenovo IdeaPad U150 | 303 | ideapad Lenovo IdeaPad U150 |
304 | thinkpad Lenovo Thinkpad | ||
300 | 305 | ||
301 | STAC9200 | 306 | STAC9200 |
302 | ======== | 307 | ======== |
@@ -404,6 +409,7 @@ STAC92HD83* | |||
404 | mic-ref Reference board with power management for ports | 409 | mic-ref Reference board with power management for ports |
405 | dell-s14 Dell laptop | 410 | dell-s14 Dell laptop |
406 | hp HP laptops with (inverted) mute-LED | 411 | hp HP laptops with (inverted) mute-LED |
412 | hp-dv7-4000 HP dv-7 4000 | ||
407 | auto BIOS setup (default) | 413 | auto BIOS setup (default) |
408 | 414 | ||
409 | STAC9872 | 415 | STAC9872 |
@@ -416,3 +422,7 @@ Cirrus Logic CS4206/4207 | |||
416 | mbp55 MacBook Pro 5,5 | 422 | mbp55 MacBook Pro 5,5 |
417 | imac27 IMac 27 Inch | 423 | imac27 IMac 27 Inch |
418 | auto BIOS setup (default) | 424 | auto BIOS setup (default) |
425 | |||
426 | VIA VT17xx/VT18xx/VT20xx | ||
427 | ======================== | ||
428 | auto BIOS setup (default) | ||
diff --git a/Documentation/usb/proc_usb_info.txt b/Documentation/usb/proc_usb_info.txt index fafcd4723260..afe596d5f201 100644 --- a/Documentation/usb/proc_usb_info.txt +++ b/Documentation/usb/proc_usb_info.txt | |||
@@ -1,12 +1,17 @@ | |||
1 | /proc/bus/usb filesystem output | 1 | /proc/bus/usb filesystem output |
2 | =============================== | 2 | =============================== |
3 | (version 2003.05.30) | 3 | (version 2010.09.13) |
4 | 4 | ||
5 | 5 | ||
6 | The usbfs filesystem for USB devices is traditionally mounted at | 6 | The usbfs filesystem for USB devices is traditionally mounted at |
7 | /proc/bus/usb. It provides the /proc/bus/usb/devices file, as well as | 7 | /proc/bus/usb. It provides the /proc/bus/usb/devices file, as well as |
8 | the /proc/bus/usb/BBB/DDD files. | 8 | the /proc/bus/usb/BBB/DDD files. |
9 | 9 | ||
10 | In many modern systems the usbfs filsystem isn't used at all. Instead | ||
11 | USB device nodes are created under /dev/usb/ or someplace similar. The | ||
12 | "devices" file is available in debugfs, typically as | ||
13 | /sys/kernel/debug/usb/devices. | ||
14 | |||
10 | 15 | ||
11 | **NOTE**: If /proc/bus/usb appears empty, and a host controller | 16 | **NOTE**: If /proc/bus/usb appears empty, and a host controller |
12 | driver has been linked, then you need to mount the | 17 | driver has been linked, then you need to mount the |
@@ -106,8 +111,8 @@ Legend: | |||
106 | 111 | ||
107 | Topology info: | 112 | Topology info: |
108 | 113 | ||
109 | T: Bus=dd Lev=dd Prnt=dd Port=dd Cnt=dd Dev#=ddd Spd=ddd MxCh=dd | 114 | T: Bus=dd Lev=dd Prnt=dd Port=dd Cnt=dd Dev#=ddd Spd=dddd MxCh=dd |
110 | | | | | | | | | |__MaxChildren | 115 | | | | | | | | | |__MaxChildren |
111 | | | | | | | | |__Device Speed in Mbps | 116 | | | | | | | | |__Device Speed in Mbps |
112 | | | | | | | |__DeviceNumber | 117 | | | | | | | |__DeviceNumber |
113 | | | | | | |__Count of devices at this level | 118 | | | | | | |__Count of devices at this level |
@@ -120,8 +125,13 @@ T: Bus=dd Lev=dd Prnt=dd Port=dd Cnt=dd Dev#=ddd Spd=ddd MxCh=dd | |||
120 | Speed may be: | 125 | Speed may be: |
121 | 1.5 Mbit/s for low speed USB | 126 | 1.5 Mbit/s for low speed USB |
122 | 12 Mbit/s for full speed USB | 127 | 12 Mbit/s for full speed USB |
123 | 480 Mbit/s for high speed USB (added for USB 2.0) | 128 | 480 Mbit/s for high speed USB (added for USB 2.0); |
129 | also used for Wireless USB, which has no fixed speed | ||
130 | 5000 Mbit/s for SuperSpeed USB (added for USB 3.0) | ||
124 | 131 | ||
132 | For reasons lost in the mists of time, the Port number is always | ||
133 | too low by 1. For example, a device plugged into port 4 will | ||
134 | show up with "Port=03". | ||
125 | 135 | ||
126 | Bandwidth info: | 136 | Bandwidth info: |
127 | B: Alloc=ddd/ddd us (xx%), #Int=ddd, #Iso=ddd | 137 | B: Alloc=ddd/ddd us (xx%), #Int=ddd, #Iso=ddd |
@@ -291,7 +301,7 @@ Here's an example, from a system which has a UHCI root hub, | |||
291 | an external hub connected to the root hub, and a mouse and | 301 | an external hub connected to the root hub, and a mouse and |
292 | a serial converter connected to the external hub. | 302 | a serial converter connected to the external hub. |
293 | 303 | ||
294 | T: Bus=00 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#= 1 Spd=12 MxCh= 2 | 304 | T: Bus=00 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#= 1 Spd=12 MxCh= 2 |
295 | B: Alloc= 28/900 us ( 3%), #Int= 2, #Iso= 0 | 305 | B: Alloc= 28/900 us ( 3%), #Int= 2, #Iso= 0 |
296 | D: Ver= 1.00 Cls=09(hub ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1 | 306 | D: Ver= 1.00 Cls=09(hub ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1 |
297 | P: Vendor=0000 ProdID=0000 Rev= 0.00 | 307 | P: Vendor=0000 ProdID=0000 Rev= 0.00 |
@@ -301,21 +311,21 @@ C:* #Ifs= 1 Cfg#= 1 Atr=40 MxPwr= 0mA | |||
301 | I: If#= 0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub | 311 | I: If#= 0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub |
302 | E: Ad=81(I) Atr=03(Int.) MxPS= 8 Ivl=255ms | 312 | E: Ad=81(I) Atr=03(Int.) MxPS= 8 Ivl=255ms |
303 | 313 | ||
304 | T: Bus=00 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 2 Spd=12 MxCh= 4 | 314 | T: Bus=00 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 2 Spd=12 MxCh= 4 |
305 | D: Ver= 1.00 Cls=09(hub ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1 | 315 | D: Ver= 1.00 Cls=09(hub ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1 |
306 | P: Vendor=0451 ProdID=1446 Rev= 1.00 | 316 | P: Vendor=0451 ProdID=1446 Rev= 1.00 |
307 | C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=100mA | 317 | C:* #Ifs= 1 Cfg#= 1 Atr=e0 MxPwr=100mA |
308 | I: If#= 0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub | 318 | I: If#= 0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub |
309 | E: Ad=81(I) Atr=03(Int.) MxPS= 1 Ivl=255ms | 319 | E: Ad=81(I) Atr=03(Int.) MxPS= 1 Ivl=255ms |
310 | 320 | ||
311 | T: Bus=00 Lev=02 Prnt=02 Port=00 Cnt=01 Dev#= 3 Spd=1.5 MxCh= 0 | 321 | T: Bus=00 Lev=02 Prnt=02 Port=00 Cnt=01 Dev#= 3 Spd=1.5 MxCh= 0 |
312 | D: Ver= 1.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1 | 322 | D: Ver= 1.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1 |
313 | P: Vendor=04b4 ProdID=0001 Rev= 0.00 | 323 | P: Vendor=04b4 ProdID=0001 Rev= 0.00 |
314 | C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=100mA | 324 | C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=100mA |
315 | I: If#= 0 Alt= 0 #EPs= 1 Cls=03(HID ) Sub=01 Prot=02 Driver=mouse | 325 | I: If#= 0 Alt= 0 #EPs= 1 Cls=03(HID ) Sub=01 Prot=02 Driver=mouse |
316 | E: Ad=81(I) Atr=03(Int.) MxPS= 3 Ivl= 10ms | 326 | E: Ad=81(I) Atr=03(Int.) MxPS= 3 Ivl= 10ms |
317 | 327 | ||
318 | T: Bus=00 Lev=02 Prnt=02 Port=02 Cnt=02 Dev#= 4 Spd=12 MxCh= 0 | 328 | T: Bus=00 Lev=02 Prnt=02 Port=02 Cnt=02 Dev#= 4 Spd=12 MxCh= 0 |
319 | D: Ver= 1.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1 | 329 | D: Ver= 1.00 Cls=00(>ifc ) Sub=00 Prot=00 MxPS= 8 #Cfgs= 1 |
320 | P: Vendor=0565 ProdID=0001 Rev= 1.08 | 330 | P: Vendor=0565 ProdID=0001 Rev= 1.08 |
321 | S: Manufacturer=Peracom Networks, Inc. | 331 | S: Manufacturer=Peracom Networks, Inc. |
@@ -330,12 +340,12 @@ E: Ad=82(I) Atr=03(Int.) MxPS= 8 Ivl= 8ms | |||
330 | Selecting only the "T:" and "I:" lines from this (for example, by using | 340 | Selecting only the "T:" and "I:" lines from this (for example, by using |
331 | "procusb ti"), we have: | 341 | "procusb ti"), we have: |
332 | 342 | ||
333 | T: Bus=00 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#= 1 Spd=12 MxCh= 2 | 343 | T: Bus=00 Lev=00 Prnt=00 Port=00 Cnt=00 Dev#= 1 Spd=12 MxCh= 2 |
334 | T: Bus=00 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 2 Spd=12 MxCh= 4 | 344 | T: Bus=00 Lev=01 Prnt=01 Port=00 Cnt=01 Dev#= 2 Spd=12 MxCh= 4 |
335 | I: If#= 0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub | 345 | I: If#= 0 Alt= 0 #EPs= 1 Cls=09(hub ) Sub=00 Prot=00 Driver=hub |
336 | T: Bus=00 Lev=02 Prnt=02 Port=00 Cnt=01 Dev#= 3 Spd=1.5 MxCh= 0 | 346 | T: Bus=00 Lev=02 Prnt=02 Port=00 Cnt=01 Dev#= 3 Spd=1.5 MxCh= 0 |
337 | I: If#= 0 Alt= 0 #EPs= 1 Cls=03(HID ) Sub=01 Prot=02 Driver=mouse | 347 | I: If#= 0 Alt= 0 #EPs= 1 Cls=03(HID ) Sub=01 Prot=02 Driver=mouse |
338 | T: Bus=00 Lev=02 Prnt=02 Port=02 Cnt=02 Dev#= 4 Spd=12 MxCh= 0 | 348 | T: Bus=00 Lev=02 Prnt=02 Port=02 Cnt=02 Dev#= 4 Spd=12 MxCh= 0 |
339 | I: If#= 0 Alt= 0 #EPs= 3 Cls=00(>ifc ) Sub=00 Prot=00 Driver=serial | 349 | I: If#= 0 Alt= 0 #EPs= 3 Cls=00(>ifc ) Sub=00 Prot=00 Driver=serial |
340 | 350 | ||
341 | 351 | ||
diff --git a/Documentation/vm/page-types.c b/Documentation/vm/page-types.c index ccd951fa94ee..cc96ee2666f2 100644 --- a/Documentation/vm/page-types.c +++ b/Documentation/vm/page-types.c | |||
@@ -478,7 +478,7 @@ static void prepare_hwpoison_fd(void) | |||
478 | } | 478 | } |
479 | 479 | ||
480 | if (opt_unpoison && !hwpoison_forget_fd) { | 480 | if (opt_unpoison && !hwpoison_forget_fd) { |
481 | sprintf(buf, "%s/renew-pfn", hwpoison_debug_fs); | 481 | sprintf(buf, "%s/unpoison-pfn", hwpoison_debug_fs); |
482 | hwpoison_forget_fd = checked_open(buf, O_WRONLY); | 482 | hwpoison_forget_fd = checked_open(buf, O_WRONLY); |
483 | } | 483 | } |
484 | } | 484 | } |
diff --git a/Documentation/workqueue.txt b/Documentation/workqueue.txt new file mode 100644 index 000000000000..996a27d9b8db --- /dev/null +++ b/Documentation/workqueue.txt | |||
@@ -0,0 +1,381 @@ | |||
1 | |||
2 | Concurrency Managed Workqueue (cmwq) | ||
3 | |||
4 | September, 2010 Tejun Heo <tj@kernel.org> | ||
5 | Florian Mickler <florian@mickler.org> | ||
6 | |||
7 | CONTENTS | ||
8 | |||
9 | 1. Introduction | ||
10 | 2. Why cmwq? | ||
11 | 3. The Design | ||
12 | 4. Application Programming Interface (API) | ||
13 | 5. Example Execution Scenarios | ||
14 | 6. Guidelines | ||
15 | |||
16 | |||
17 | 1. Introduction | ||
18 | |||
19 | There are many cases where an asynchronous process execution context | ||
20 | is needed and the workqueue (wq) API is the most commonly used | ||
21 | mechanism for such cases. | ||
22 | |||
23 | When such an asynchronous execution context is needed, a work item | ||
24 | describing which function to execute is put on a queue. An | ||
25 | independent thread serves as the asynchronous execution context. The | ||
26 | queue is called workqueue and the thread is called worker. | ||
27 | |||
28 | While there are work items on the workqueue the worker executes the | ||
29 | functions associated with the work items one after the other. When | ||
30 | there is no work item left on the workqueue the worker becomes idle. | ||
31 | When a new work item gets queued, the worker begins executing again. | ||
32 | |||
33 | |||
34 | 2. Why cmwq? | ||
35 | |||
36 | In the original wq implementation, a multi threaded (MT) wq had one | ||
37 | worker thread per CPU and a single threaded (ST) wq had one worker | ||
38 | thread system-wide. A single MT wq needed to keep around the same | ||
39 | number of workers as the number of CPUs. The kernel grew a lot of MT | ||
40 | wq users over the years and with the number of CPU cores continuously | ||
41 | rising, some systems saturated the default 32k PID space just booting | ||
42 | up. | ||
43 | |||
44 | Although MT wq wasted a lot of resource, the level of concurrency | ||
45 | provided was unsatisfactory. The limitation was common to both ST and | ||
46 | MT wq albeit less severe on MT. Each wq maintained its own separate | ||
47 | worker pool. A MT wq could provide only one execution context per CPU | ||
48 | while a ST wq one for the whole system. Work items had to compete for | ||
49 | those very limited execution contexts leading to various problems | ||
50 | including proneness to deadlocks around the single execution context. | ||
51 | |||
52 | The tension between the provided level of concurrency and resource | ||
53 | usage also forced its users to make unnecessary tradeoffs like libata | ||
54 | choosing to use ST wq for polling PIOs and accepting an unnecessary | ||
55 | limitation that no two polling PIOs can progress at the same time. As | ||
56 | MT wq don't provide much better concurrency, users which require | ||
57 | higher level of concurrency, like async or fscache, had to implement | ||
58 | their own thread pool. | ||
59 | |||
60 | Concurrency Managed Workqueue (cmwq) is a reimplementation of wq with | ||
61 | focus on the following goals. | ||
62 | |||
63 | * Maintain compatibility with the original workqueue API. | ||
64 | |||
65 | * Use per-CPU unified worker pools shared by all wq to provide | ||
66 | flexible level of concurrency on demand without wasting a lot of | ||
67 | resource. | ||
68 | |||
69 | * Automatically regulate worker pool and level of concurrency so that | ||
70 | the API users don't need to worry about such details. | ||
71 | |||
72 | |||
73 | 3. The Design | ||
74 | |||
75 | In order to ease the asynchronous execution of functions a new | ||
76 | abstraction, the work item, is introduced. | ||
77 | |||
78 | A work item is a simple struct that holds a pointer to the function | ||
79 | that is to be executed asynchronously. Whenever a driver or subsystem | ||
80 | wants a function to be executed asynchronously it has to set up a work | ||
81 | item pointing to that function and queue that work item on a | ||
82 | workqueue. | ||
83 | |||
84 | Special purpose threads, called worker threads, execute the functions | ||
85 | off of the queue, one after the other. If no work is queued, the | ||
86 | worker threads become idle. These worker threads are managed in so | ||
87 | called thread-pools. | ||
88 | |||
89 | The cmwq design differentiates between the user-facing workqueues that | ||
90 | subsystems and drivers queue work items on and the backend mechanism | ||
91 | which manages thread-pool and processes the queued work items. | ||
92 | |||
93 | The backend is called gcwq. There is one gcwq for each possible CPU | ||
94 | and one gcwq to serve work items queued on unbound workqueues. | ||
95 | |||
96 | Subsystems and drivers can create and queue work items through special | ||
97 | workqueue API functions as they see fit. They can influence some | ||
98 | aspects of the way the work items are executed by setting flags on the | ||
99 | workqueue they are putting the work item on. These flags include | ||
100 | things like CPU locality, reentrancy, concurrency limits and more. To | ||
101 | get a detailed overview refer to the API description of | ||
102 | alloc_workqueue() below. | ||
103 | |||
104 | When a work item is queued to a workqueue, the target gcwq is | ||
105 | determined according to the queue parameters and workqueue attributes | ||
106 | and appended on the shared worklist of the gcwq. For example, unless | ||
107 | specifically overridden, a work item of a bound workqueue will be | ||
108 | queued on the worklist of exactly that gcwq that is associated to the | ||
109 | CPU the issuer is running on. | ||
110 | |||
111 | For any worker pool implementation, managing the concurrency level | ||
112 | (how many execution contexts are active) is an important issue. cmwq | ||
113 | tries to keep the concurrency at a minimal but sufficient level. | ||
114 | Minimal to save resources and sufficient in that the system is used at | ||
115 | its full capacity. | ||
116 | |||
117 | Each gcwq bound to an actual CPU implements concurrency management by | ||
118 | hooking into the scheduler. The gcwq is notified whenever an active | ||
119 | worker wakes up or sleeps and keeps track of the number of the | ||
120 | currently runnable workers. Generally, work items are not expected to | ||
121 | hog a CPU and consume many cycles. That means maintaining just enough | ||
122 | concurrency to prevent work processing from stalling should be | ||
123 | optimal. As long as there are one or more runnable workers on the | ||
124 | CPU, the gcwq doesn't start execution of a new work, but, when the | ||
125 | last running worker goes to sleep, it immediately schedules a new | ||
126 | worker so that the CPU doesn't sit idle while there are pending work | ||
127 | items. This allows using a minimal number of workers without losing | ||
128 | execution bandwidth. | ||
129 | |||
130 | Keeping idle workers around doesn't cost other than the memory space | ||
131 | for kthreads, so cmwq holds onto idle ones for a while before killing | ||
132 | them. | ||
133 | |||
134 | For an unbound wq, the above concurrency management doesn't apply and | ||
135 | the gcwq for the pseudo unbound CPU tries to start executing all work | ||
136 | items as soon as possible. The responsibility of regulating | ||
137 | concurrency level is on the users. There is also a flag to mark a | ||
138 | bound wq to ignore the concurrency management. Please refer to the | ||
139 | API section for details. | ||
140 | |||
141 | Forward progress guarantee relies on that workers can be created when | ||
142 | more execution contexts are necessary, which in turn is guaranteed | ||
143 | through the use of rescue workers. All work items which might be used | ||
144 | on code paths that handle memory reclaim are required to be queued on | ||
145 | wq's that have a rescue-worker reserved for execution under memory | ||
146 | pressure. Else it is possible that the thread-pool deadlocks waiting | ||
147 | for execution contexts to free up. | ||
148 | |||
149 | |||
150 | 4. Application Programming Interface (API) | ||
151 | |||
152 | alloc_workqueue() allocates a wq. The original create_*workqueue() | ||
153 | functions are deprecated and scheduled for removal. alloc_workqueue() | ||
154 | takes three arguments - @name, @flags and @max_active. @name is the | ||
155 | name of the wq and also used as the name of the rescuer thread if | ||
156 | there is one. | ||
157 | |||
158 | A wq no longer manages execution resources but serves as a domain for | ||
159 | forward progress guarantee, flush and work item attributes. @flags | ||
160 | and @max_active control how work items are assigned execution | ||
161 | resources, scheduled and executed. | ||
162 | |||
163 | @flags: | ||
164 | |||
165 | WQ_NON_REENTRANT | ||
166 | |||
167 | By default, a wq guarantees non-reentrance only on the same | ||
168 | CPU. A work item may not be executed concurrently on the same | ||
169 | CPU by multiple workers but is allowed to be executed | ||
170 | concurrently on multiple CPUs. This flag makes sure | ||
171 | non-reentrance is enforced across all CPUs. Work items queued | ||
172 | to a non-reentrant wq are guaranteed to be executed by at most | ||
173 | one worker system-wide at any given time. | ||
174 | |||
175 | WQ_UNBOUND | ||
176 | |||
177 | Work items queued to an unbound wq are served by a special | ||
178 | gcwq which hosts workers which are not bound to any specific | ||
179 | CPU. This makes the wq behave as a simple execution context | ||
180 | provider without concurrency management. The unbound gcwq | ||
181 | tries to start execution of work items as soon as possible. | ||
182 | Unbound wq sacrifices locality but is useful for the following | ||
183 | cases. | ||
184 | |||
185 | * Wide fluctuation in the concurrency level requirement is | ||
186 | expected and using bound wq may end up creating large number | ||
187 | of mostly unused workers across different CPUs as the issuer | ||
188 | hops through different CPUs. | ||
189 | |||
190 | * Long running CPU intensive workloads which can be better | ||
191 | managed by the system scheduler. | ||
192 | |||
193 | WQ_FREEZEABLE | ||
194 | |||
195 | A freezeable wq participates in the freeze phase of the system | ||
196 | suspend operations. Work items on the wq are drained and no | ||
197 | new work item starts execution until thawed. | ||
198 | |||
199 | WQ_MEM_RECLAIM | ||
200 | |||
201 | All wq which might be used in the memory reclaim paths _MUST_ | ||
202 | have this flag set. The wq is guaranteed to have at least one | ||
203 | execution context regardless of memory pressure. | ||
204 | |||
205 | WQ_HIGHPRI | ||
206 | |||
207 | Work items of a highpri wq are queued at the head of the | ||
208 | worklist of the target gcwq and start execution regardless of | ||
209 | the current concurrency level. In other words, highpri work | ||
210 | items will always start execution as soon as execution | ||
211 | resource is available. | ||
212 | |||
213 | Ordering among highpri work items is preserved - a highpri | ||
214 | work item queued after another highpri work item will start | ||
215 | execution after the earlier highpri work item starts. | ||
216 | |||
217 | Although highpri work items are not held back by other | ||
218 | runnable work items, they still contribute to the concurrency | ||
219 | level. Highpri work items in runnable state will prevent | ||
220 | non-highpri work items from starting execution. | ||
221 | |||
222 | This flag is meaningless for unbound wq. | ||
223 | |||
224 | WQ_CPU_INTENSIVE | ||
225 | |||
226 | Work items of a CPU intensive wq do not contribute to the | ||
227 | concurrency level. In other words, runnable CPU intensive | ||
228 | work items will not prevent other work items from starting | ||
229 | execution. This is useful for bound work items which are | ||
230 | expected to hog CPU cycles so that their execution is | ||
231 | regulated by the system scheduler. | ||
232 | |||
233 | Although CPU intensive work items don't contribute to the | ||
234 | concurrency level, start of their executions is still | ||
235 | regulated by the concurrency management and runnable | ||
236 | non-CPU-intensive work items can delay execution of CPU | ||
237 | intensive work items. | ||
238 | |||
239 | This flag is meaningless for unbound wq. | ||
240 | |||
241 | WQ_HIGHPRI | WQ_CPU_INTENSIVE | ||
242 | |||
243 | This combination makes the wq avoid interaction with | ||
244 | concurrency management completely and behave as a simple | ||
245 | per-CPU execution context provider. Work items queued on a | ||
246 | highpri CPU-intensive wq start execution as soon as resources | ||
247 | are available and don't affect execution of other work items. | ||
248 | |||
249 | @max_active: | ||
250 | |||
251 | @max_active determines the maximum number of execution contexts per | ||
252 | CPU which can be assigned to the work items of a wq. For example, | ||
253 | with @max_active of 16, at most 16 work items of the wq can be | ||
254 | executing at the same time per CPU. | ||
255 | |||
256 | Currently, for a bound wq, the maximum limit for @max_active is 512 | ||
257 | and the default value used when 0 is specified is 256. For an unbound | ||
258 | wq, the limit is higher of 512 and 4 * num_possible_cpus(). These | ||
259 | values are chosen sufficiently high such that they are not the | ||
260 | limiting factor while providing protection in runaway cases. | ||
261 | |||
262 | The number of active work items of a wq is usually regulated by the | ||
263 | users of the wq, more specifically, by how many work items the users | ||
264 | may queue at the same time. Unless there is a specific need for | ||
265 | throttling the number of active work items, specifying '0' is | ||
266 | recommended. | ||
267 | |||
268 | Some users depend on the strict execution ordering of ST wq. The | ||
269 | combination of @max_active of 1 and WQ_UNBOUND is used to achieve this | ||
270 | behavior. Work items on such wq are always queued to the unbound gcwq | ||
271 | and only one work item can be active at any given time thus achieving | ||
272 | the same ordering property as ST wq. | ||
273 | |||
274 | |||
275 | 5. Example Execution Scenarios | ||
276 | |||
277 | The following example execution scenarios try to illustrate how cmwq | ||
278 | behave under different configurations. | ||
279 | |||
280 | Work items w0, w1, w2 are queued to a bound wq q0 on the same CPU. | ||
281 | w0 burns CPU for 5ms then sleeps for 10ms then burns CPU for 5ms | ||
282 | again before finishing. w1 and w2 burn CPU for 5ms then sleep for | ||
283 | 10ms. | ||
284 | |||
285 | Ignoring all other tasks, works and processing overhead, and assuming | ||
286 | simple FIFO scheduling, the following is one highly simplified version | ||
287 | of possible sequences of events with the original wq. | ||
288 | |||
289 | TIME IN MSECS EVENT | ||
290 | 0 w0 starts and burns CPU | ||
291 | 5 w0 sleeps | ||
292 | 15 w0 wakes up and burns CPU | ||
293 | 20 w0 finishes | ||
294 | 20 w1 starts and burns CPU | ||
295 | 25 w1 sleeps | ||
296 | 35 w1 wakes up and finishes | ||
297 | 35 w2 starts and burns CPU | ||
298 | 40 w2 sleeps | ||
299 | 50 w2 wakes up and finishes | ||
300 | |||
301 | And with cmwq with @max_active >= 3, | ||
302 | |||
303 | TIME IN MSECS EVENT | ||
304 | 0 w0 starts and burns CPU | ||
305 | 5 w0 sleeps | ||
306 | 5 w1 starts and burns CPU | ||
307 | 10 w1 sleeps | ||
308 | 10 w2 starts and burns CPU | ||
309 | 15 w2 sleeps | ||
310 | 15 w0 wakes up and burns CPU | ||
311 | 20 w0 finishes | ||
312 | 20 w1 wakes up and finishes | ||
313 | 25 w2 wakes up and finishes | ||
314 | |||
315 | If @max_active == 2, | ||
316 | |||
317 | TIME IN MSECS EVENT | ||
318 | 0 w0 starts and burns CPU | ||
319 | 5 w0 sleeps | ||
320 | 5 w1 starts and burns CPU | ||
321 | 10 w1 sleeps | ||
322 | 15 w0 wakes up and burns CPU | ||
323 | 20 w0 finishes | ||
324 | 20 w1 wakes up and finishes | ||
325 | 20 w2 starts and burns CPU | ||
326 | 25 w2 sleeps | ||
327 | 35 w2 wakes up and finishes | ||
328 | |||
329 | Now, let's assume w1 and w2 are queued to a different wq q1 which has | ||
330 | WQ_HIGHPRI set, | ||
331 | |||
332 | TIME IN MSECS EVENT | ||
333 | 0 w1 and w2 start and burn CPU | ||
334 | 5 w1 sleeps | ||
335 | 10 w2 sleeps | ||
336 | 10 w0 starts and burns CPU | ||
337 | 15 w0 sleeps | ||
338 | 15 w1 wakes up and finishes | ||
339 | 20 w2 wakes up and finishes | ||
340 | 25 w0 wakes up and burns CPU | ||
341 | 30 w0 finishes | ||
342 | |||
343 | If q1 has WQ_CPU_INTENSIVE set, | ||
344 | |||
345 | TIME IN MSECS EVENT | ||
346 | 0 w0 starts and burns CPU | ||
347 | 5 w0 sleeps | ||
348 | 5 w1 and w2 start and burn CPU | ||
349 | 10 w1 sleeps | ||
350 | 15 w2 sleeps | ||
351 | 15 w0 wakes up and burns CPU | ||
352 | 20 w0 finishes | ||
353 | 20 w1 wakes up and finishes | ||
354 | 25 w2 wakes up and finishes | ||
355 | |||
356 | |||
357 | 6. Guidelines | ||
358 | |||
359 | * Do not forget to use WQ_MEM_RECLAIM if a wq may process work items | ||
360 | which are used during memory reclaim. Each wq with WQ_MEM_RECLAIM | ||
361 | set has an execution context reserved for it. If there is | ||
362 | dependency among multiple work items used during memory reclaim, | ||
363 | they should be queued to separate wq each with WQ_MEM_RECLAIM. | ||
364 | |||
365 | * Unless strict ordering is required, there is no need to use ST wq. | ||
366 | |||
367 | * Unless there is a specific need, using 0 for @max_active is | ||
368 | recommended. In most use cases, concurrency level usually stays | ||
369 | well under the default limit. | ||
370 | |||
371 | * A wq serves as a domain for forward progress guarantee | ||
372 | (WQ_MEM_RECLAIM, flush and work item attributes. Work items which | ||
373 | are not involved in memory reclaim and don't need to be flushed as a | ||
374 | part of a group of work items, and don't require any special | ||
375 | attribute, can use one of the system wq. There is no difference in | ||
376 | execution characteristics between using a dedicated wq and a system | ||
377 | wq. | ||
378 | |||
379 | * Unless work items are expected to consume a huge amount of CPU | ||
380 | cycles, using a bound wq is usually beneficial due to the increased | ||
381 | level of locality in wq operations and work item execution. | ||
diff --git a/Documentation/x86/x86_64/kernel-stacks b/Documentation/x86/x86_64/kernel-stacks index 5ad65d51fb95..a01eec5d1d0b 100644 --- a/Documentation/x86/x86_64/kernel-stacks +++ b/Documentation/x86/x86_64/kernel-stacks | |||
@@ -18,9 +18,9 @@ specialized stacks contain no useful data. The main CPU stacks are: | |||
18 | Used for external hardware interrupts. If this is the first external | 18 | Used for external hardware interrupts. If this is the first external |
19 | hardware interrupt (i.e. not a nested hardware interrupt) then the | 19 | hardware interrupt (i.e. not a nested hardware interrupt) then the |
20 | kernel switches from the current task to the interrupt stack. Like | 20 | kernel switches from the current task to the interrupt stack. Like |
21 | the split thread and interrupt stacks on i386 (with CONFIG_4KSTACKS), | 21 | the split thread and interrupt stacks on i386, this gives more room |
22 | this gives more room for kernel interrupt processing without having | 22 | for kernel interrupt processing without having to increase the size |
23 | to increase the size of every per thread stack. | 23 | of every per thread stack. |
24 | 24 | ||
25 | The interrupt stack is also used when processing a softirq. | 25 | The interrupt stack is also used when processing a softirq. |
26 | 26 | ||