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authorTakashi Iwai <tiwai@suse.de>2010-09-14 10:15:29 -0400
committerTakashi Iwai <tiwai@suse.de>2010-09-14 10:15:29 -0400
commitf3fbba6efbab93b9850821d41a75b02286d18315 (patch)
treee2a680674d334c6e455d1a89a4dbfc3f549cb6d1 /Documentation
parent15c5ab607045e278ebf4d2ca4aea2250617d50ca (diff)
parent147fcf1c211f1a87bf4d0711b7e9637f3d6ce080 (diff)
Merge branch 'fix/misc' into topic/misc
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/DocBook/device-drivers.tmpl1
-rw-r--r--Documentation/DocBook/kernel-api.tmpl1
-rw-r--r--Documentation/DocBook/kernel-locking.tmpl6
-rw-r--r--Documentation/DocBook/tracepoint.tmpl5
-rw-r--r--Documentation/block/cfq-iosched.txt45
-rw-r--r--Documentation/cgroups/blkio-controller.txt28
-rw-r--r--Documentation/gpio.txt22
-rw-r--r--Documentation/kernel-doc-nano-HOWTO.txt5
-rw-r--r--Documentation/kernel-parameters.txt17
-rw-r--r--Documentation/mutex-design.txt3
-rw-r--r--Documentation/sound/alsa/HD-Audio-Models.txt1
11 files changed, 116 insertions, 18 deletions
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/kernel-api.tmpl b/Documentation/DocBook/kernel-api.tmpl
index a20c6f6fffc3..6899f471fb15 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>
diff --git a/Documentation/DocBook/kernel-locking.tmpl b/Documentation/DocBook/kernel-locking.tmpl
index 0b1a3f97f285..a0d479d1e1dd 100644
--- a/Documentation/DocBook/kernel-locking.tmpl
+++ b/Documentation/DocBook/kernel-locking.tmpl
@@ -1961,6 +1961,12 @@ machines due to caching.
1961 </sect1> 1961 </sect1>
1962 </chapter> 1962 </chapter>
1963 1963
1964 <chapter id="apiref">
1965 <title>Mutex API reference</title>
1966!Iinclude/linux/mutex.h
1967!Ekernel/mutex.c
1968 </chapter>
1969
1964 <chapter id="references"> 1970 <chapter id="references">
1965 <title>Further reading</title> 1971 <title>Further reading</title>
1966 1972
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/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 @@
1CFQ ioscheduler tunables
2========================
3
4slice_idle
5----------
6This specifies how long CFQ should idle for next request on certain cfq queues
7(for sequential workloads) and service trees (for random workloads) before
8queue is expired and CFQ selects next queue to dispatch from.
9
10By default slice_idle is a non-zero value. That means by default we idle on
11queues/service trees. This can be very helpful on highly seeky media like
12single spindle SATA/SAS disks where we can cut down on overall number of
13seeks and see improved throughput.
14
15Setting slice_idle to 0 will remove all the idling on queues/service tree
16level and one should see an overall improved throughput on faster storage
17devices like multiple SATA/SAS disks in hardware RAID configuration. The down
18side is that isolation provided from WRITES also goes down and notion of
19IO priority becomes weaker.
20
21So depending on storage and workload, it might be useful to set slice_idle=0.
22In general I think for SATA/SAS disks and software RAID of SATA/SAS disks
23keeping slice_idle enabled should be useful. For any configurations where
24there are multiple spindles behind single LUN (Host based hardware RAID
25controller or for storage arrays), setting slice_idle=0 might end up in better
26throughput and acceptable latencies.
27
28CFQ IOPS Mode for group scheduling
29===================================
30Basic CFQ design is to provide priority based time slices. Higher priority
31process gets bigger time slice and lower priority process gets smaller time
32slice. Measuring time becomes harder if storage is fast and supports NCQ and
33it would be better to dispatch multiple requests from multiple cfq queues in
34request queue at a time. In such scenario, it is not possible to measure time
35consumed by single queue accurately.
36
37What is possible though is to measure number of requests dispatched from a
38single queue and also allow dispatch from multiple cfq queue at the same time.
39This effectively becomes the fairness in terms of IOPS (IO operations per
40second).
41
42If one sets slice_idle=0 and if storage supports NCQ, CFQ internally switches
43to IOPS mode and starts providing fairness in terms of number of requests
44dispatched. Note that this mode switching takes effect only for group
45scheduling. For non-cgroup users nothing should change.
diff --git a/Documentation/cgroups/blkio-controller.txt b/Documentation/cgroups/blkio-controller.txt
index 48e0b21b0059..6919d62591d9 100644
--- a/Documentation/cgroups/blkio-controller.txt
+++ b/Documentation/cgroups/blkio-controller.txt
@@ -217,6 +217,7 @@ Details of cgroup files
217CFQ sysfs tunable 217CFQ sysfs tunable
218================= 218=================
219/sys/block/<disk>/queue/iosched/group_isolation 219/sys/block/<disk>/queue/iosched/group_isolation
220-----------------------------------------------
220 221
221If group_isolation=1, it provides stronger isolation between groups at the 222If group_isolation=1, it provides stronger isolation between groups at the
222expense of throughput. By default group_isolation is 0. In general that 223expense of throughput. By default group_isolation is 0. In general that
@@ -243,6 +244,33 @@ By default one should run with group_isolation=0. If that is not sufficient
243and one wants stronger isolation between groups, then set group_isolation=1 244and one wants stronger isolation between groups, then set group_isolation=1
244but this will come at cost of reduced throughput. 245but this will come at cost of reduced throughput.
245 246
247/sys/block/<disk>/queue/iosched/slice_idle
248------------------------------------------
249On a faster hardware CFQ can be slow, especially with sequential workload.
250This happens because CFQ idles on a single queue and single queue might not
251drive deeper request queue depths to keep the storage busy. In such scenarios
252one can try setting slice_idle=0 and that would switch CFQ to IOPS
253(IO operations per second) mode on NCQ supporting hardware.
254
255That means CFQ will not idle between cfq queues of a cfq group and hence be
256able to driver higher queue depth and achieve better throughput. That also
257means that cfq provides fairness among groups in terms of IOPS and not in
258terms of disk time.
259
260/sys/block/<disk>/queue/iosched/group_idle
261------------------------------------------
262If one disables idling on individual cfq queues and cfq service trees by
263setting slice_idle=0, group_idle kicks in. That means CFQ will still idle
264on the group in an attempt to provide fairness among groups.
265
266By default group_idle is same as slice_idle and does not do anything if
267slice_idle is enabled.
268
269One can experience an overall throughput drop if you have created multiple
270groups and put applications in that group which are not driving enough
271IO to keep disk busy. In that case set group_idle=0, and CFQ will not idle
272on individual groups and throughput should improve.
273
246What works 274What works
247========== 275==========
248- Currently only sync IO queues are support. All the buffered writes are 276- Currently only sync IO queues are support. All the buffered writes are
diff --git a/Documentation/gpio.txt b/Documentation/gpio.txt
index d96a6dba5748..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
110If you want to initialize a structure with an invalid GPIO number, use 110If you want to initialize a structure with an invalid GPIO number, use
111some negative number (perhaps "-EINVAL"); that will never be valid. To 111some negative number (perhaps "-EINVAL"); that will never be valid. To
112test if a number could reference a GPIO, you may use this predicate: 112test if such number from such a structure could reference a GPIO, you
113may use this predicate:
113 114
114 int gpio_is_valid(int number); 115 int gpio_is_valid(int number);
115 116
116A number that's not valid will be rejected by calls which may request 117A number that's not valid will be rejected by calls which may request
117or free GPIOs (see below). Other numbers may also be rejected; for 118or free GPIOs (see below). Other numbers may also be rejected; for
118example, a number might be valid but unused on a given board. 119example, a number might be valid but temporarily unused on a given board.
119
120Whether a platform supports multiple GPIO controllers is currently a
121platform-specific implementation issue.
122 120
121Whether a platform supports multiple GPIO controllers is a platform-specific
122implementation issue, as are whether that support can leave "holes" in the space
123of GPIO numbers, and whether new controllers can be added at runtime. Such issues
124can affect things including whether adjacent GPIO numbers are both valid.
123 125
124Using GPIOs 126Using GPIOs
125----------- 127-----------
@@ -480,12 +482,16 @@ To support this framework, a platform's Kconfig will "select" either
480ARCH_REQUIRE_GPIOLIB or ARCH_WANT_OPTIONAL_GPIOLIB 482ARCH_REQUIRE_GPIOLIB or ARCH_WANT_OPTIONAL_GPIOLIB
481and arrange that its <asm/gpio.h> includes <asm-generic/gpio.h> and defines 483and arrange that its <asm/gpio.h> includes <asm-generic/gpio.h> and defines
482three functions: gpio_get_value(), gpio_set_value(), and gpio_cansleep(). 484three functions: gpio_get_value(), gpio_set_value(), and gpio_cansleep().
483They may also want to provide a custom value for ARCH_NR_GPIOS.
484 485
485ARCH_REQUIRE_GPIOLIB means that the gpio-lib code will always get compiled 486It may also provide a custom value for ARCH_NR_GPIOS, so that it better
487reflects the number of GPIOs in actual use on that platform, without
488wasting static table space. (It should count both built-in/SoC GPIOs and
489also ones on GPIO expanders.
490
491ARCH_REQUIRE_GPIOLIB means that the gpiolib code will always get compiled
486into the kernel on that architecture. 492into the kernel on that architecture.
487 493
488ARCH_WANT_OPTIONAL_GPIOLIB means the gpio-lib code defaults to off and the user 494ARCH_WANT_OPTIONAL_GPIOLIB means the gpiolib code defaults to off and the user
489can enable it and build it into the kernel optionally. 495can enable it and build it into the kernel optionally.
490 496
491If neither of these options are selected, the platform does not support 497If neither of these options are selected, the platform does not support
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.
345section titled <section title> from <filename>. 345section titled <section title> from <filename>.
346Spaces are allowed in <section title>; do not quote the <section title>. 346Spaces 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
349all DOC: sections and documented functions, symbols, etc. are used.
350This makes sense to use when you use !F/!P only and want to verify
351that all documentation is included.
352
348Tim. 353Tim.
349*/ <twaugh@redhat.com> 354*/ <twaugh@redhat.com>
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index f084af0cb8e0..8dd7248508a9 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1974,15 +1974,18 @@ and is between 256 and 4096 characters. It is defined in the file
1974 force Enable ASPM even on devices that claim not to support it. 1974 force Enable ASPM even on devices that claim not to support it.
1975 WARNING: Forcing ASPM on may cause system lockups. 1975 WARNING: Forcing ASPM on may cause system lockups.
1976 1976
1977 pcie_ports= [PCIE] PCIe ports handling:
1978 auto Ask the BIOS whether or not to use native PCIe services
1979 associated with PCIe ports (PME, hot-plug, AER). Use
1980 them only if that is allowed by the BIOS.
1981 native Use native PCIe services associated with PCIe ports
1982 unconditionally.
1983 compat Treat PCIe ports as PCI-to-PCI bridges, disable the PCIe
1984 ports driver.
1985
1977 pcie_pme= [PCIE,PM] Native PCIe PME signaling options: 1986 pcie_pme= [PCIE,PM] Native PCIe PME signaling options:
1978 Format: {auto|force}[,nomsi]
1979 auto Use native PCIe PME signaling if the BIOS allows the
1980 kernel to control PCIe config registers of root ports.
1981 force Use native PCIe PME signaling even if the BIOS refuses
1982 to allow the kernel to control the relevant PCIe config
1983 registers.
1984 nomsi Do not use MSI for native PCIe PME signaling (this makes 1987 nomsi Do not use MSI for native PCIe PME signaling (this makes
1985 all PCIe root ports use INTx for everything). 1988 all PCIe root ports use INTx for all services).
1986 1989
1987 pcmv= [HW,PCMCIA] BadgePAD 4 1990 pcmv= [HW,PCMCIA] BadgePAD 4
1988 1991
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
9mutex semantics are sufficient for your code, then there are a couple 9mutex semantics are sufficient for your code, then there are a couple
10of advantages of mutexes: 10of 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/sound/alsa/HD-Audio-Models.txt b/Documentation/sound/alsa/HD-Audio-Models.txt
index ce46fa1e643e..37c6aad5e590 100644
--- a/Documentation/sound/alsa/HD-Audio-Models.txt
+++ b/Documentation/sound/alsa/HD-Audio-Models.txt
@@ -296,6 +296,7 @@ Conexant 5051
296Conexant 5066 296Conexant 5066
297============= 297=============
298 laptop Basic Laptop config (default) 298 laptop Basic Laptop config (default)
299 hp-laptop HP laptops, e g G60
299 dell-laptop Dell laptops 300 dell-laptop Dell laptops
300 dell-vostro Dell Vostro 301 dell-vostro Dell Vostro
301 olpc-xo-1_5 OLPC XO 1.5 302 olpc-xo-1_5 OLPC XO 1.5