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-rw-r--r--Documentation/feature-removal-schedule.txt49
-rw-r--r--Documentation/filesystems/proc.txt2
-rw-r--r--Documentation/hwmon/amc6821102
-rw-r--r--Documentation/hwmon/k10temp17
-rw-r--r--Documentation/input/multi-touch-protocol.txt48
-rw-r--r--Documentation/ioctl/ioctl-number.txt203
-rw-r--r--Documentation/kernel-doc-nano-HOWTO.txt12
-rw-r--r--Documentation/networking/3c509.txt12
-rw-r--r--Documentation/trace/ftrace-design.txt26
-rw-r--r--Documentation/trace/ftrace.txt2
-rw-r--r--Documentation/trace/ring-buffer-design.txt56
11 files changed, 428 insertions, 101 deletions
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index 870d190fe617..0a46833c1b76 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -493,3 +493,52 @@ Why: These two features use non-standard interfaces. There are the
493Who: Corentin Chary <corentin.chary@gmail.com> 493Who: Corentin Chary <corentin.chary@gmail.com>
494 494
495---------------------------- 495----------------------------
496
497What: usbvideo quickcam_messenger driver
498When: 2.6.35
499Files: drivers/media/video/usbvideo/quickcam_messenger.[ch]
500Why: obsolete v4l1 driver replaced by gspca_stv06xx
501Who: Hans de Goede <hdegoede@redhat.com>
502
503----------------------------
504
505What: ov511 v4l1 driver
506When: 2.6.35
507Files: drivers/media/video/ov511.[ch]
508Why: obsolete v4l1 driver replaced by gspca_ov519
509Who: Hans de Goede <hdegoede@redhat.com>
510
511----------------------------
512
513What: w9968cf v4l1 driver
514When: 2.6.35
515Files: drivers/media/video/w9968cf*.[ch]
516Why: obsolete v4l1 driver replaced by gspca_ov519
517Who: Hans de Goede <hdegoede@redhat.com>
518
519----------------------------
520
521What: ovcamchip sensor framework
522When: 2.6.35
523Files: drivers/media/video/ovcamchip/*
524Why: Only used by obsoleted v4l1 drivers
525Who: Hans de Goede <hdegoede@redhat.com>
526
527----------------------------
528
529What: stv680 v4l1 driver
530When: 2.6.35
531Files: drivers/media/video/stv680.[ch]
532Why: obsolete v4l1 driver replaced by gspca_stv0680
533Who: Hans de Goede <hdegoede@redhat.com>
534
535----------------------------
536
537What: zc0301 v4l driver
538When: 2.6.35
539Files: drivers/media/video/zc0301/*
540Why: Duplicate functionality with the gspca_zc3xx driver, zc0301 only
541 supports 2 USB-ID's (because it only supports a limited set of
542 sensors) wich are also supported by the gspca_zc3xx driver
543 (which supports 53 USB-ID's in total)
544Who: Hans de Goede <hdegoede@redhat.com>
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 220cc6376ef8..0d07513a67a6 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -177,7 +177,6 @@ read the file /proc/PID/status:
177 CapBnd: ffffffffffffffff 177 CapBnd: ffffffffffffffff
178 voluntary_ctxt_switches: 0 178 voluntary_ctxt_switches: 0
179 nonvoluntary_ctxt_switches: 1 179 nonvoluntary_ctxt_switches: 1
180 Stack usage: 12 kB
181 180
182This shows you nearly the same information you would get if you viewed it with 181This shows you nearly the same information you would get if you viewed it with
183the ps command. In fact, ps uses the proc file system to obtain its 182the ps command. In fact, ps uses the proc file system to obtain its
@@ -231,7 +230,6 @@ Table 1-2: Contents of the statm files (as of 2.6.30-rc7)
231 Mems_allowed_list Same as previous, but in "list format" 230 Mems_allowed_list Same as previous, but in "list format"
232 voluntary_ctxt_switches number of voluntary context switches 231 voluntary_ctxt_switches number of voluntary context switches
233 nonvoluntary_ctxt_switches number of non voluntary context switches 232 nonvoluntary_ctxt_switches number of non voluntary context switches
234 Stack usage: stack usage high water mark (round up to page size)
235.............................................................................. 233..............................................................................
236 234
237Table 1-3: Contents of the statm files (as of 2.6.8-rc3) 235Table 1-3: Contents of the statm files (as of 2.6.8-rc3)
diff --git a/Documentation/hwmon/amc6821 b/Documentation/hwmon/amc6821
new file mode 100644
index 000000000000..ced8359c50f8
--- /dev/null
+++ b/Documentation/hwmon/amc6821
@@ -0,0 +1,102 @@
1Kernel driver amc6821
2=====================
3
4Supported chips:
5 Texas Instruments AMC6821
6 Prefix: 'amc6821'
7 Addresses scanned: 0x18, 0x19, 0x1a, 0x2c, 0x2d, 0x2e, 0x4c, 0x4d, 0x4e
8 Datasheet: http://focus.ti.com/docs/prod/folders/print/amc6821.html
9
10Authors:
11 Tomaz Mertelj <tomaz.mertelj@guest.arnes.si>
12
13
14Description
15-----------
16
17This driver implements support for the Texas Instruments amc6821 chip.
18The chip has one on-chip and one remote temperature sensor and one pwm fan
19regulator.
20The pwm can be controlled either from software or automatically.
21
22The driver provides the following sensor accesses in sysfs:
23
24temp1_input ro on-chip temperature
25temp1_min rw "
26temp1_max rw "
27temp1_crit rw "
28temp1_min_alarm ro "
29temp1_max_alarm ro "
30temp1_crit_alarm ro "
31
32temp2_input ro remote temperature
33temp2_min rw "
34temp2_max rw "
35temp2_crit rw "
36temp2_min_alarm ro "
37temp2_max_alarm ro "
38temp2_crit_alarm ro "
39temp2_fault ro "
40
41fan1_input ro tachometer speed
42fan1_min rw "
43fan1_max rw "
44fan1_fault ro "
45fan1_div rw Fan divisor can be either 2 or 4.
46
47pwm1 rw pwm1
48pwm1_enable rw regulator mode, 1=open loop, 2=fan controlled
49 by remote temperature, 3=fan controlled by
50 combination of the on-chip temperature and
51 remote-sensor temperature,
52pwm1_auto_channels_temp ro 1 if pwm_enable==2, 3 if pwm_enable==3
53pwm1_auto_point1_pwm ro Hardwired to 0, shared for both
54 temperature channels.
55pwm1_auto_point2_pwm rw This value is shared for both temperature
56 channels.
57pwm1_auto_point3_pwm rw Hardwired to 255, shared for both
58 temperature channels.
59
60temp1_auto_point1_temp ro Hardwired to temp2_auto_point1_temp
61 which is rw. Below this temperature fan stops.
62temp1_auto_point2_temp rw The low-temperature limit of the proportional
63 range. Below this temperature
64 pwm1 = pwm1_auto_point2_pwm. It can go from
65 0 degree C to 124 degree C in steps of
66 4 degree C. Read it out after writing to get
67 the actual value.
68temp1_auto_point3_temp rw Above this temperature fan runs at maximum
69 speed. It can go from temp1_auto_point2_temp.
70 It can only have certain discrete values
71 which depend on temp1_auto_point2_temp and
72 pwm1_auto_point2_pwm. Read it out after
73 writing to get the actual value.
74
75temp2_auto_point1_temp rw Must be between 0 degree C and 63 degree C and
76 it defines the passive cooling temperature.
77 Below this temperature the fan stops in
78 the closed loop mode.
79temp2_auto_point2_temp rw The low-temperature limit of the proportional
80 range. Below this temperature
81 pwm1 = pwm1_auto_point2_pwm. It can go from
82 0 degree C to 124 degree C in steps
83 of 4 degree C.
84
85temp2_auto_point3_temp rw Above this temperature fan runs at maximum
86 speed. It can only have certain discrete
87 values which depend on temp2_auto_point2_temp
88 and pwm1_auto_point2_pwm. Read it out after
89 writing to get actual value.
90
91
92Module parameters
93-----------------
94
95If your board has a BIOS that initializes the amc6821 correctly, you should
96load the module with: init=0.
97
98If your board BIOS doesn't initialize the chip, or you want
99different settings, you can set the following parameters:
100init=1,
101pwminv: 0 default pwm output, 1 inverts pwm output.
102
diff --git a/Documentation/hwmon/k10temp b/Documentation/hwmon/k10temp
index a7a18d453a51..6526eee525a6 100644
--- a/Documentation/hwmon/k10temp
+++ b/Documentation/hwmon/k10temp
@@ -3,8 +3,8 @@ Kernel driver k10temp
3 3
4Supported chips: 4Supported chips:
5* AMD Family 10h processors: 5* AMD Family 10h processors:
6 Socket F: Quad-Core/Six-Core/Embedded Opteron 6 Socket F: Quad-Core/Six-Core/Embedded Opteron (but see below)
7 Socket AM2+: Opteron, Phenom (II) X3/X4 7 Socket AM2+: Quad-Core Opteron, Phenom (II) X3/X4, Athlon X2 (but see below)
8 Socket AM3: Quad-Core Opteron, Athlon/Phenom II X2/X3/X4, Sempron II 8 Socket AM3: Quad-Core Opteron, Athlon/Phenom II X2/X3/X4, Sempron II
9 Socket S1G3: Athlon II, Sempron, Turion II 9 Socket S1G3: Athlon II, Sempron, Turion II
10* AMD Family 11h processors: 10* AMD Family 11h processors:
@@ -36,10 +36,15 @@ Description
36This driver permits reading of the internal temperature sensor of AMD 36This driver permits reading of the internal temperature sensor of AMD
37Family 10h and 11h processors. 37Family 10h and 11h processors.
38 38
39All these processors have a sensor, but on older revisions of Family 10h 39All these processors have a sensor, but on those for Socket F or AM2+,
40processors, the sensor may return inconsistent values (erratum 319). The 40the sensor may return inconsistent values (erratum 319). The driver
41driver will refuse to load on these revisions unless you specify the 41will refuse to load on these revisions unless you specify the "force=1"
42"force=1" module parameter. 42module parameter.
43
44Due to technical reasons, the driver can detect only the mainboard's
45socket type, not the processor's actual capabilities. Therefore, if you
46are using an AM3 processor on an AM2+ mainboard, you can safely use the
47"force=1" parameter.
43 48
44There is one temperature measurement value, available as temp1_input in 49There is one temperature measurement value, available as temp1_input in
45sysfs. It is measured in degrees Celsius with a resolution of 1/8th degree. 50sysfs. It is measured in degrees Celsius with a resolution of 1/8th degree.
diff --git a/Documentation/input/multi-touch-protocol.txt b/Documentation/input/multi-touch-protocol.txt
index a12ea3b586e6..8490480ce432 100644
--- a/Documentation/input/multi-touch-protocol.txt
+++ b/Documentation/input/multi-touch-protocol.txt
@@ -27,12 +27,30 @@ set of events/packets.
27 27
28A set of ABS_MT events with the desired properties is defined. The events 28A set of ABS_MT events with the desired properties is defined. The events
29are divided into categories, to allow for partial implementation. The 29are divided into categories, to allow for partial implementation. The
30minimum set consists of ABS_MT_TOUCH_MAJOR, ABS_MT_POSITION_X and 30minimum set consists of ABS_MT_POSITION_X and ABS_MT_POSITION_Y, which
31ABS_MT_POSITION_Y, which allows for multiple fingers to be tracked. If the 31allows for multiple fingers to be tracked. If the device supports it, the
32device supports it, the ABS_MT_WIDTH_MAJOR may be used to provide the size 32ABS_MT_TOUCH_MAJOR and ABS_MT_WIDTH_MAJOR may be used to provide the size
33of the approaching finger. Anisotropy and direction may be specified with 33of the contact area and approaching finger, respectively.
34ABS_MT_TOUCH_MINOR, ABS_MT_WIDTH_MINOR and ABS_MT_ORIENTATION. The 34
35ABS_MT_TOOL_TYPE may be used to specify whether the touching tool is a 35The TOUCH and WIDTH parameters have a geometrical interpretation; imagine
36looking through a window at someone gently holding a finger against the
37glass. You will see two regions, one inner region consisting of the part
38of the finger actually touching the glass, and one outer region formed by
39the perimeter of the finger. The diameter of the inner region is the
40ABS_MT_TOUCH_MAJOR, the diameter of the outer region is
41ABS_MT_WIDTH_MAJOR. Now imagine the person pressing the finger harder
42against the glass. The inner region will increase, and in general, the
43ratio ABS_MT_TOUCH_MAJOR / ABS_MT_WIDTH_MAJOR, which is always smaller than
44unity, is related to the finger pressure. For pressure-based devices,
45ABS_MT_PRESSURE may be used to provide the pressure on the contact area
46instead.
47
48In addition to the MAJOR parameters, the oval shape of the finger can be
49described by adding the MINOR parameters, such that MAJOR and MINOR are the
50major and minor axis of an ellipse. Finally, the orientation of the oval
51shape can be describe with the ORIENTATION parameter.
52
53The ABS_MT_TOOL_TYPE may be used to specify whether the touching tool is a
36finger or a pen or something else. Devices with more granular information 54finger or a pen or something else. Devices with more granular information
37may specify general shapes as blobs, i.e., as a sequence of rectangular 55may specify general shapes as blobs, i.e., as a sequence of rectangular
38shapes grouped together by an ABS_MT_BLOB_ID. Finally, for the few devices 56shapes grouped together by an ABS_MT_BLOB_ID. Finally, for the few devices
@@ -42,11 +60,9 @@ report finger tracking from hardware [5].
42Here is what a minimal event sequence for a two-finger touch would look 60Here is what a minimal event sequence for a two-finger touch would look
43like: 61like:
44 62
45 ABS_MT_TOUCH_MAJOR
46 ABS_MT_POSITION_X 63 ABS_MT_POSITION_X
47 ABS_MT_POSITION_Y 64 ABS_MT_POSITION_Y
48 SYN_MT_REPORT 65 SYN_MT_REPORT
49 ABS_MT_TOUCH_MAJOR
50 ABS_MT_POSITION_X 66 ABS_MT_POSITION_X
51 ABS_MT_POSITION_Y 67 ABS_MT_POSITION_Y
52 SYN_MT_REPORT 68 SYN_MT_REPORT
@@ -87,6 +103,12 @@ the contact. The ratio ABS_MT_TOUCH_MAJOR / ABS_MT_WIDTH_MAJOR approximates
87the notion of pressure. The fingers of the hand and the palm all have 103the notion of pressure. The fingers of the hand and the palm all have
88different characteristic widths [1]. 104different characteristic widths [1].
89 105
106ABS_MT_PRESSURE
107
108The pressure, in arbitrary units, on the contact area. May be used instead
109of TOUCH and WIDTH for pressure-based devices or any device with a spatial
110signal intensity distribution.
111
90ABS_MT_ORIENTATION 112ABS_MT_ORIENTATION
91 113
92The orientation of the ellipse. The value should describe a signed quarter 114The orientation of the ellipse. The value should describe a signed quarter
@@ -170,6 +192,16 @@ There are a few devices that support trackingID in hardware. User space can
170make use of these native identifiers to reduce bandwidth and cpu usage. 192make use of these native identifiers to reduce bandwidth and cpu usage.
171 193
172 194
195Gestures
196--------
197
198In the specific application of creating gesture events, the TOUCH and WIDTH
199parameters can be used to, e.g., approximate finger pressure or distinguish
200between index finger and thumb. With the addition of the MINOR parameters,
201one can also distinguish between a sweeping finger and a pointing finger,
202and with ORIENTATION, one can detect twisting of fingers.
203
204
173Notes 205Notes
174----- 206-----
175 207
diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt
index 947374977ca5..35cf64d4436d 100644
--- a/Documentation/ioctl/ioctl-number.txt
+++ b/Documentation/ioctl/ioctl-number.txt
@@ -56,10 +56,11 @@ Following this convention is good because:
56(5) When following the convention, the driver code can use generic 56(5) When following the convention, the driver code can use generic
57 code to copy the parameters between user and kernel space. 57 code to copy the parameters between user and kernel space.
58 58
59This table lists ioctls visible from user land for Linux/i386. It contains 59This table lists ioctls visible from user land for Linux/x86. It contains
60most drivers up to 2.3.14, but I know I am missing some. 60most drivers up to 2.6.31, but I know I am missing some. There has been
61no attempt to list non-X86 architectures or ioctls from drivers/staging/.
61 62
62Code Seq# Include File Comments 63Code Seq#(hex) Include File Comments
63======================================================== 64========================================================
640x00 00-1F linux/fs.h conflict! 650x00 00-1F linux/fs.h conflict!
650x00 00-1F scsi/scsi_ioctl.h conflict! 660x00 00-1F scsi/scsi_ioctl.h conflict!
@@ -69,119 +70,228 @@ Code Seq# Include File Comments
690x03 all linux/hdreg.h 700x03 all linux/hdreg.h
700x04 D2-DC linux/umsdos_fs.h Dead since 2.6.11, but don't reuse these. 710x04 D2-DC linux/umsdos_fs.h Dead since 2.6.11, but don't reuse these.
710x06 all linux/lp.h 720x06 all linux/lp.h
720x09 all linux/md.h 730x09 all linux/raid/md_u.h
740x10 00-0F drivers/char/s390/vmcp.h
730x12 all linux/fs.h 750x12 all linux/fs.h
74 linux/blkpg.h 76 linux/blkpg.h
750x1b all InfiniBand Subsystem <http://www.openib.org/> 770x1b all InfiniBand Subsystem <http://www.openib.org/>
760x20 all drivers/cdrom/cm206.h 780x20 all drivers/cdrom/cm206.h
770x22 all scsi/sg.h 790x22 all scsi/sg.h
78'#' 00-3F IEEE 1394 Subsystem Block for the entire subsystem 80'#' 00-3F IEEE 1394 Subsystem Block for the entire subsystem
81'$' 00-0F linux/perf_counter.h, linux/perf_event.h
79'1' 00-1F <linux/timepps.h> PPS kit from Ulrich Windl 82'1' 00-1F <linux/timepps.h> PPS kit from Ulrich Windl
80 <ftp://ftp.de.kernel.org/pub/linux/daemons/ntp/PPS/> 83 <ftp://ftp.de.kernel.org/pub/linux/daemons/ntp/PPS/>
84'2' 01-04 linux/i2o.h
85'3' 00-0F drivers/s390/char/raw3270.h conflict!
86'3' 00-1F linux/suspend_ioctls.h conflict!
87 and kernel/power/user.c
81'8' all SNP8023 advanced NIC card 88'8' all SNP8023 advanced NIC card
82 <mailto:mcr@solidum.com> 89 <mailto:mcr@solidum.com>
83'A' 00-1F linux/apm_bios.h 90'@' 00-0F linux/radeonfb.h conflict!
91'@' 00-0F drivers/video/aty/aty128fb.c conflict!
92'A' 00-1F linux/apm_bios.h conflict!
93'A' 00-0F linux/agpgart.h conflict!
94 and drivers/char/agp/compat_ioctl.h
95'A' 00-7F sound/asound.h conflict!
96'B' 00-1F linux/cciss_ioctl.h conflict!
97'B' 00-0F include/linux/pmu.h conflict!
84'B' C0-FF advanced bbus 98'B' C0-FF advanced bbus
85 <mailto:maassen@uni-freiburg.de> 99 <mailto:maassen@uni-freiburg.de>
86'C' all linux/soundcard.h 100'C' all linux/soundcard.h conflict!
101'C' 01-2F linux/capi.h conflict!
102'C' F0-FF drivers/net/wan/cosa.h conflict!
87'D' all arch/s390/include/asm/dasd.h 103'D' all arch/s390/include/asm/dasd.h
88'E' all linux/input.h 104'D' 40-5F drivers/scsi/dpt/dtpi_ioctl.h
89'F' all linux/fb.h 105'D' 05 drivers/scsi/pmcraid.h
90'H' all linux/hiddev.h 106'E' all linux/input.h conflict!
91'I' all linux/isdn.h 107'E' 00-0F xen/evtchn.h conflict!
108'F' all linux/fb.h conflict!
109'F' 01-02 drivers/scsi/pmcraid.h conflict!
110'F' 20 drivers/video/fsl-diu-fb.h conflict!
111'F' 20 drivers/video/intelfb/intelfb.h conflict!
112'F' 20 linux/ivtvfb.h conflict!
113'F' 20 linux/matroxfb.h conflict!
114'F' 20 drivers/video/aty/atyfb_base.c conflict!
115'F' 00-0F video/da8xx-fb.h conflict!
116'F' 80-8F linux/arcfb.h conflict!
117'F' DD video/sstfb.h conflict!
118'G' 00-3F drivers/misc/sgi-gru/grulib.h conflict!
119'G' 00-0F linux/gigaset_dev.h conflict!
120'H' 00-7F linux/hiddev.h conflict!
121'H' 00-0F linux/hidraw.h conflict!
122'H' 00-0F sound/asound.h conflict!
123'H' 20-40 sound/asound_fm.h conflict!
124'H' 80-8F sound/sfnt_info.h conflict!
125'H' 10-8F sound/emu10k1.h conflict!
126'H' 10-1F sound/sb16_csp.h conflict!
127'H' 10-1F sound/hda_hwdep.h conflict!
128'H' 40-4F sound/hdspm.h conflict!
129'H' 40-4F sound/hdsp.h conflict!
130'H' 90 sound/usb/usx2y/usb_stream.h
131'H' C0-F0 net/bluetooth/hci.h conflict!
132'H' C0-DF net/bluetooth/hidp/hidp.h conflict!
133'H' C0-DF net/bluetooth/cmtp/cmtp.h conflict!
134'H' C0-DF net/bluetooth/bnep/bnep.h conflict!
135'I' all linux/isdn.h conflict!
136'I' 00-0F drivers/isdn/divert/isdn_divert.h conflict!
137'I' 40-4F linux/mISDNif.h conflict!
92'J' 00-1F drivers/scsi/gdth_ioctl.h 138'J' 00-1F drivers/scsi/gdth_ioctl.h
93'K' all linux/kd.h 139'K' all linux/kd.h
94'L' 00-1F linux/loop.h 140'L' 00-1F linux/loop.h conflict!
95'L' 20-2F driver/usb/misc/vstusb.h 141'L' 10-1F drivers/scsi/mpt2sas/mpt2sas_ctl.h conflict!
142'L' 20-2F linux/usb/vstusb.h
96'L' E0-FF linux/ppdd.h encrypted disk device driver 143'L' E0-FF linux/ppdd.h encrypted disk device driver
97 <http://linux01.gwdg.de/~alatham/ppdd.html> 144 <http://linux01.gwdg.de/~alatham/ppdd.html>
98'M' all linux/soundcard.h 145'M' all linux/soundcard.h conflict!
146'M' 01-16 mtd/mtd-abi.h conflict!
147 and drivers/mtd/mtdchar.c
148'M' 01-03 drivers/scsi/megaraid/megaraid_sas.h
149'M' 00-0F drivers/video/fsl-diu-fb.h conflict!
99'N' 00-1F drivers/usb/scanner.h 150'N' 00-1F drivers/usb/scanner.h
100'O' 00-02 include/mtd/ubi-user.h UBI 151'O' 00-06 mtd/ubi-user.h UBI
101'P' all linux/soundcard.h 152'P' all linux/soundcard.h conflict!
153'P' 60-6F sound/sscape_ioctl.h conflict!
154'P' 00-0F drivers/usb/class/usblp.c conflict!
102'Q' all linux/soundcard.h 155'Q' all linux/soundcard.h
103'R' 00-1F linux/random.h 156'R' 00-1F linux/random.h conflict!
157'R' 01 linux/rfkill.h conflict!
158'R' 01-0F media/rds.h conflict!
159'R' C0-DF net/bluetooth/rfcomm.h
104'S' all linux/cdrom.h conflict! 160'S' all linux/cdrom.h conflict!
105'S' 80-81 scsi/scsi_ioctl.h conflict! 161'S' 80-81 scsi/scsi_ioctl.h conflict!
106'S' 82-FF scsi/scsi.h conflict! 162'S' 82-FF scsi/scsi.h conflict!
163'S' 00-7F sound/asequencer.h conflict!
107'T' all linux/soundcard.h conflict! 164'T' all linux/soundcard.h conflict!
165'T' 00-AF sound/asound.h conflict!
108'T' all arch/x86/include/asm/ioctls.h conflict! 166'T' all arch/x86/include/asm/ioctls.h conflict!
109'U' 00-EF linux/drivers/usb/usb.h 167'T' C0-DF linux/if_tun.h conflict!
110'V' all linux/vt.h 168'U' all sound/asound.h conflict!
169'U' 00-0F drivers/media/video/uvc/uvcvideo.h conflict!
170'U' 00-CF linux/uinput.h conflict!
171'U' 00-EF linux/usbdevice_fs.h
172'U' C0-CF drivers/bluetooth/hci_uart.h
173'V' all linux/vt.h conflict!
174'V' all linux/videodev2.h conflict!
175'V' C0 linux/ivtvfb.h conflict!
176'V' C0 linux/ivtv.h conflict!
177'V' C0 media/davinci/vpfe_capture.h conflict!
178'V' C0 media/si4713.h conflict!
179'V' C0-CF drivers/media/video/mxb.h conflict!
111'W' 00-1F linux/watchdog.h conflict! 180'W' 00-1F linux/watchdog.h conflict!
112'W' 00-1F linux/wanrouter.h conflict! 181'W' 00-1F linux/wanrouter.h conflict!
113'X' all linux/xfs_fs.h 182'W' 00-3F sound/asound.h conflict!
183'X' all fs/xfs/xfs_fs.h conflict!
184 and fs/xfs/linux-2.6/xfs_ioctl32.h
185 and include/linux/falloc.h
186 and linux/fs.h
187'X' all fs/ocfs2/ocfs_fs.h conflict!
188'X' 01 linux/pktcdvd.h conflict!
114'Y' all linux/cyclades.h 189'Y' all linux/cyclades.h
115'[' 00-07 linux/usb/usbtmc.h USB Test and Measurement Devices 190'Z' 14-15 drivers/message/fusion/mptctl.h
191'[' 00-07 linux/usb/tmc.h USB Test and Measurement Devices
116 <mailto:gregkh@suse.de> 192 <mailto:gregkh@suse.de>
117'a' all ATM on linux 193'a' all linux/atm*.h, linux/sonet.h ATM on linux
118 <http://lrcwww.epfl.ch/linux-atm/magic.html> 194 <http://lrcwww.epfl.ch/linux-atm/magic.html>
119'b' 00-FF bit3 vme host bridge 195'b' 00-FF conflict! bit3 vme host bridge
120 <mailto:natalia@nikhefk.nikhef.nl> 196 <mailto:natalia@nikhefk.nikhef.nl>
197'b' 00-0F media/bt819.h conflict!
198'c' all linux/cm4000_cs.h conflict!
121'c' 00-7F linux/comstats.h conflict! 199'c' 00-7F linux/comstats.h conflict!
122'c' 00-7F linux/coda.h conflict! 200'c' 00-7F linux/coda.h conflict!
123'c' 80-9F arch/s390/include/asm/chsc.h 201'c' 00-1F linux/chio.h conflict!
124'c' A0-AF arch/x86/include/asm/msr.h 202'c' 80-9F arch/s390/include/asm/chsc.h conflict!
203'c' A0-AF arch/x86/include/asm/msr.h conflict!
125'd' 00-FF linux/char/drm/drm/h conflict! 204'd' 00-FF linux/char/drm/drm/h conflict!
205'd' 02-40 pcmcia/ds.h conflict!
206'd' 10-3F drivers/media/video/dabusb.h conflict!
207'd' C0-CF drivers/media/video/saa7191.h conflict!
126'd' F0-FF linux/digi1.h 208'd' F0-FF linux/digi1.h
127'e' all linux/digi1.h conflict! 209'e' all linux/digi1.h conflict!
128'e' 00-1F net/irda/irtty.h conflict! 210'e' 00-1F drivers/net/irda/irtty-sir.h conflict!
129'f' 00-1F linux/ext2_fs.h 211'f' 00-1F linux/ext2_fs.h conflict!
130'h' 00-7F Charon filesystem 212'f' 00-1F linux/ext3_fs.h conflict!
213'f' 00-0F fs/jfs/jfs_dinode.h conflict!
214'f' 00-0F fs/ext4/ext4.h conflict!
215'f' 00-0F linux/fs.h conflict!
216'f' 00-0F fs/ocfs2/ocfs2_fs.h conflict!
217'g' 00-0F linux/usb/gadgetfs.h
218'g' 20-2F linux/usb/g_printer.h
219'h' 00-7F conflict! Charon filesystem
131 <mailto:zapman@interlan.net> 220 <mailto:zapman@interlan.net>
132'i' 00-3F linux/i2o.h 221'h' 00-1F linux/hpet.h conflict!
222'i' 00-3F linux/i2o-dev.h conflict!
223'i' 0B-1F linux/ipmi.h conflict!
224'i' 80-8F linux/i8k.h
133'j' 00-3F linux/joystick.h 225'j' 00-3F linux/joystick.h
226'k' 00-0F linux/spi/spidev.h conflict!
227'k' 00-05 video/kyro.h conflict!
134'l' 00-3F linux/tcfs_fs.h transparent cryptographic file system 228'l' 00-3F linux/tcfs_fs.h transparent cryptographic file system
135 <http://mikonos.dia.unisa.it/tcfs> 229 <http://mikonos.dia.unisa.it/tcfs>
136'l' 40-7F linux/udf_fs_i.h in development: 230'l' 40-7F linux/udf_fs_i.h in development:
137 <http://sourceforge.net/projects/linux-udf/> 231 <http://sourceforge.net/projects/linux-udf/>
138'm' 00-09 linux/mmtimer.h 232'm' 00-09 linux/mmtimer.h conflict!
139'm' all linux/mtio.h conflict! 233'm' all linux/mtio.h conflict!
140'm' all linux/soundcard.h conflict! 234'm' all linux/soundcard.h conflict!
141'm' all linux/synclink.h conflict! 235'm' all linux/synclink.h conflict!
236'm' 00-19 drivers/message/fusion/mptctl.h conflict!
237'm' 00 drivers/scsi/megaraid/megaraid_ioctl.h conflict!
142'm' 00-1F net/irda/irmod.h conflict! 238'm' 00-1F net/irda/irmod.h conflict!
143'n' 00-7F linux/ncp_fs.h 239'n' 00-7F linux/ncp_fs.h and fs/ncpfs/ioctl.c
144'n' 80-8F linux/nilfs2_fs.h NILFS2 240'n' 80-8F linux/nilfs2_fs.h NILFS2
145'n' E0-FF video/matrox.h matroxfb 241'n' E0-FF linux/matroxfb.h matroxfb
146'o' 00-1F fs/ocfs2/ocfs2_fs.h OCFS2 242'o' 00-1F fs/ocfs2/ocfs2_fs.h OCFS2
147'o' 00-03 include/mtd/ubi-user.h conflict! (OCFS2 and UBI overlaps) 243'o' 00-03 mtd/ubi-user.h conflict! (OCFS2 and UBI overlaps)
148'o' 40-41 include/mtd/ubi-user.h UBI 244'o' 40-41 mtd/ubi-user.h UBI
149'o' 01-A1 include/linux/dvb/*.h DVB 245'o' 01-A1 linux/dvb/*.h DVB
150'p' 00-0F linux/phantom.h conflict! (OpenHaptics needs this) 246'p' 00-0F linux/phantom.h conflict! (OpenHaptics needs this)
247'p' 00-1F linux/rtc.h conflict!
151'p' 00-3F linux/mc146818rtc.h conflict! 248'p' 00-3F linux/mc146818rtc.h conflict!
152'p' 40-7F linux/nvram.h 249'p' 40-7F linux/nvram.h
153'p' 80-9F user-space parport 250'p' 80-9F linux/ppdev.h user-space parport
154 <mailto:tim@cyberelk.net> 251 <mailto:tim@cyberelk.net>
155'p' a1-a4 linux/pps.h LinuxPPS 252'p' A1-A4 linux/pps.h LinuxPPS
156 <mailto:giometti@linux.it> 253 <mailto:giometti@linux.it>
157'q' 00-1F linux/serio.h 254'q' 00-1F linux/serio.h
158'q' 80-FF Internet PhoneJACK, Internet LineJACK 255'q' 80-FF linux/telephony.h Internet PhoneJACK, Internet LineJACK
159 <http://www.quicknet.net> 256 linux/ixjuser.h <http://www.quicknet.net>
160'r' 00-1F linux/msdos_fs.h 257'r' 00-1F linux/msdos_fs.h and fs/fat/dir.c
161's' all linux/cdk.h 258's' all linux/cdk.h
162't' 00-7F linux/if_ppp.h 259't' 00-7F linux/if_ppp.h
163't' 80-8F linux/isdn_ppp.h 260't' 80-8F linux/isdn_ppp.h
261't' 90 linux/toshiba.h
164'u' 00-1F linux/smb_fs.h 262'u' 00-1F linux/smb_fs.h
165'v' 00-1F linux/ext2_fs.h conflict!
166'v' all linux/videodev.h conflict! 263'v' all linux/videodev.h conflict!
264'v' 00-1F linux/ext2_fs.h conflict!
265'v' 00-1F linux/fs.h conflict!
266'v' 00-0F linux/sonypi.h conflict!
267'v' C0-CF drivers/media/video/ov511.h conflict!
268'v' C0-DF media/pwc-ioctl.h conflict!
269'v' C0-FF linux/meye.h conflict!
270'v' C0-CF drivers/media/video/zoran/zoran.h conflict!
271'v' D0-DF drivers/media/video/cpia2/cpia2dev.h conflict!
167'w' all CERN SCI driver 272'w' all CERN SCI driver
168'y' 00-1F packet based user level communications 273'y' 00-1F packet based user level communications
169 <mailto:zapman@interlan.net> 274 <mailto:zapman@interlan.net>
170'z' 00-3F CAN bus card 275'z' 00-3F CAN bus card conflict!
171 <mailto:hdstich@connectu.ulm.circular.de> 276 <mailto:hdstich@connectu.ulm.circular.de>
172'z' 40-7F CAN bus card 277'z' 40-7F CAN bus card conflict!
173 <mailto:oe@port.de> 278 <mailto:oe@port.de>
279'z' 10-4F drivers/s390/crypto/zcrypt_api.h conflict!
1740x80 00-1F linux/fb.h 2800x80 00-1F linux/fb.h
1750x81 00-1F linux/videotext.h 2810x81 00-1F linux/videotext.h
2820x88 00-3F media/ovcamchip.h
1760x89 00-06 arch/x86/include/asm/sockios.h 2830x89 00-06 arch/x86/include/asm/sockios.h
1770x89 0B-DF linux/sockios.h 2840x89 0B-DF linux/sockios.h
1780x89 E0-EF linux/sockios.h SIOCPROTOPRIVATE range 2850x89 E0-EF linux/sockios.h SIOCPROTOPRIVATE range
2860x89 E0-EF linux/dn.h PROTOPRIVATE range
1790x89 F0-FF linux/sockios.h SIOCDEVPRIVATE range 2870x89 F0-FF linux/sockios.h SIOCDEVPRIVATE range
1800x8B all linux/wireless.h 2880x8B all linux/wireless.h
1810x8C 00-3F WiNRADiO driver 2890x8C 00-3F WiNRADiO driver
182 <http://www.proximity.com.au/~brian/winradio/> 290 <http://www.proximity.com.au/~brian/winradio/>
1830x90 00 drivers/cdrom/sbpcd.h 2910x90 00 drivers/cdrom/sbpcd.h
2920x92 00-0F drivers/usb/mon/mon_bin.c
1840x93 60-7F linux/auto_fs.h 2930x93 60-7F linux/auto_fs.h
2940x94 all fs/btrfs/ioctl.h
1850x99 00-0F 537-Addinboard driver 2950x99 00-0F 537-Addinboard driver
186 <mailto:buk@buks.ipn.de> 296 <mailto:buk@buks.ipn.de>
1870xA0 all linux/sdp/sdp.h Industrial Device Project 2970xA0 all linux/sdp/sdp.h Industrial Device Project
@@ -192,17 +302,22 @@ Code Seq# Include File Comments
1920xAB 00-1F linux/nbd.h 3020xAB 00-1F linux/nbd.h
1930xAC 00-1F linux/raw.h 3030xAC 00-1F linux/raw.h
1940xAD 00 Netfilter device in development: 3040xAD 00 Netfilter device in development:
195 <mailto:rusty@rustcorp.com.au> 305 <mailto:rusty@rustcorp.com.au>
1960xAE all linux/kvm.h Kernel-based Virtual Machine 3060xAE all linux/kvm.h Kernel-based Virtual Machine
197 <mailto:kvm@vger.kernel.org> 307 <mailto:kvm@vger.kernel.org>
1980xB0 all RATIO devices in development: 3080xB0 all RATIO devices in development:
199 <mailto:vgo@ratio.de> 309 <mailto:vgo@ratio.de>
2000xB1 00-1F PPPoX <mailto:mostrows@styx.uwaterloo.ca> 3100xB1 00-1F PPPoX <mailto:mostrows@styx.uwaterloo.ca>
3110xC0 00-0F linux/usb/iowarrior.h
2010xCB 00-1F CBM serial IEC bus in development: 3120xCB 00-1F CBM serial IEC bus in development:
202 <mailto:michael.klein@puffin.lb.shuttle.de> 313 <mailto:michael.klein@puffin.lb.shuttle.de>
3140xCD 01 linux/reiserfs_fs.h
3150xCF 02 fs/cifs/ioctl.c
3160xDB 00-0F drivers/char/mwave/mwavepub.h
2030xDD 00-3F ZFCP device driver see drivers/s390/scsi/ 3170xDD 00-3F ZFCP device driver see drivers/s390/scsi/
204 <mailto:aherrman@de.ibm.com> 318 <mailto:aherrman@de.ibm.com>
2050xF3 00-3F video/sisfb.h sisfb (in development) 3190xF3 00-3F drivers/usb/misc/sisusbvga/sisusb.h sisfb (in development)
206 <mailto:thomas@winischhofer.net> 320 <mailto:thomas@winischhofer.net>
2070xF4 00-1F video/mbxfb.h mbxfb 3210xF4 00-1F video/mbxfb.h mbxfb
208 <mailto:raph@8d.com> 322 <mailto:raph@8d.com>
3230xFD all linux/dm-ioctl.h
diff --git a/Documentation/kernel-doc-nano-HOWTO.txt b/Documentation/kernel-doc-nano-HOWTO.txt
index 348b9e5e28fc..27a52b35d55b 100644
--- a/Documentation/kernel-doc-nano-HOWTO.txt
+++ b/Documentation/kernel-doc-nano-HOWTO.txt
@@ -214,11 +214,13 @@ The format of the block comment is like this:
214 * (section header: (section description)? )* 214 * (section header: (section description)? )*
215(*)?*/ 215(*)?*/
216 216
217The short function description ***cannot be multiline***, but the other 217All "description" text can span multiple lines, although the
218descriptions can be (and they can contain blank lines). If you continue 218function_name & its short description are traditionally on a single line.
219that initial short description onto a second line, that second line will 219Description text may also contain blank lines (i.e., lines that contain
220appear further down at the beginning of the description section, which is 220only a "*").
221almost certainly not what you had in mind. 221
222"section header:" names must be unique per function (or struct,
223union, typedef, enum).
222 224
223Avoid putting a spurious blank line after the function name, or else the 225Avoid putting a spurious blank line after the function name, or else the
224description will be repeated! 226description will be repeated!
diff --git a/Documentation/networking/3c509.txt b/Documentation/networking/3c509.txt
index 0643e3b7168c..3c45d5dcd63b 100644
--- a/Documentation/networking/3c509.txt
+++ b/Documentation/networking/3c509.txt
@@ -48,11 +48,11 @@ for LILO parameters for doing this:
48This configures the first found 3c509 card for IRQ 10, base I/O 0x310, and 48This configures the first found 3c509 card for IRQ 10, base I/O 0x310, and
49transceiver type 3 (10base2). The flag "0x3c509" must be set to avoid conflicts 49transceiver type 3 (10base2). The flag "0x3c509" must be set to avoid conflicts
50with other card types when overriding the I/O address. When the driver is 50with other card types when overriding the I/O address. When the driver is
51loaded as a module, only the IRQ and transceiver setting may be overridden. 51loaded as a module, only the IRQ may be overridden. For example,
52For example, setting two cards to 10base2/IRQ10 and AUI/IRQ11 is done by using 52setting two cards to IRQ10 and IRQ11 is done by using the irq module
53the xcvr and irq module options: 53option:
54 54
55 options 3c509 xcvr=3,1 irq=10,11 55 options 3c509 irq=10,11
56 56
57 57
58(2) Full-duplex mode 58(2) Full-duplex mode
@@ -77,6 +77,8 @@ operation.
77itself full-duplex capable. This is almost certainly one of two things: a full- 77itself full-duplex capable. This is almost certainly one of two things: a full-
78duplex-capable Ethernet switch (*not* a hub), or a full-duplex-capable NIC on 78duplex-capable Ethernet switch (*not* a hub), or a full-duplex-capable NIC on
79another system that's connected directly to the 3c509B via a crossover cable. 79another system that's connected directly to the 3c509B via a crossover cable.
80
81Full-duplex mode can be enabled using 'ethtool'.
80 82
81/////Extremely important caution concerning full-duplex mode///// 83/////Extremely important caution concerning full-duplex mode/////
82Understand that the 3c509B's hardware's full-duplex support is much more 84Understand that the 3c509B's hardware's full-duplex support is much more
@@ -113,6 +115,8 @@ This insured that merely upgrading the driver from an earlier version would
113never automatically enable full-duplex mode in an existing installation; 115never automatically enable full-duplex mode in an existing installation;
114it must always be explicitly enabled via one of these code in order to be 116it must always be explicitly enabled via one of these code in order to be
115activated. 117activated.
118
119The transceiver type can be changed using 'ethtool'.
116 120
117 121
118(4a) Interpretation of error messages and common problems 122(4a) Interpretation of error messages and common problems
diff --git a/Documentation/trace/ftrace-design.txt b/Documentation/trace/ftrace-design.txt
index 239f14b2b55a..6a5a579126b0 100644
--- a/Documentation/trace/ftrace-design.txt
+++ b/Documentation/trace/ftrace-design.txt
@@ -1,5 +1,6 @@
1 function tracer guts 1 function tracer guts
2 ==================== 2 ====================
3 By Mike Frysinger
3 4
4Introduction 5Introduction
5------------ 6------------
@@ -173,14 +174,16 @@ void ftrace_graph_caller(void)
173 174
174 unsigned long *frompc = &...; 175 unsigned long *frompc = &...;
175 unsigned long selfpc = <return address> - MCOUNT_INSN_SIZE; 176 unsigned long selfpc = <return address> - MCOUNT_INSN_SIZE;
176 prepare_ftrace_return(frompc, selfpc); 177 /* passing frame pointer up is optional -- see below */
178 prepare_ftrace_return(frompc, selfpc, frame_pointer);
177 179
178 /* restore all state needed by the ABI */ 180 /* restore all state needed by the ABI */
179} 181}
180#endif 182#endif
181 183
182For information on how to implement prepare_ftrace_return(), simply look at 184For information on how to implement prepare_ftrace_return(), simply look at the
183the x86 version. The only architecture-specific piece in it is the setup of 185x86 version (the frame pointer passing is optional; see the next section for
186more information). The only architecture-specific piece in it is the setup of
184the fault recovery table (the asm(...) code). The rest should be the same 187the fault recovery table (the asm(...) code). The rest should be the same
185across architectures. 188across architectures.
186 189
@@ -205,6 +208,23 @@ void return_to_handler(void)
205#endif 208#endif
206 209
207 210
211HAVE_FUNCTION_GRAPH_FP_TEST
212---------------------------
213
214An arch may pass in a unique value (frame pointer) to both the entering and
215exiting of a function. On exit, the value is compared and if it does not
216match, then it will panic the kernel. This is largely a sanity check for bad
217code generation with gcc. If gcc for your port sanely updates the frame
218pointer under different opitmization levels, then ignore this option.
219
220However, adding support for it isn't terribly difficult. In your assembly code
221that calls prepare_ftrace_return(), pass the frame pointer as the 3rd argument.
222Then in the C version of that function, do what the x86 port does and pass it
223along to ftrace_push_return_trace() instead of a stub value of 0.
224
225Similarly, when you call ftrace_return_to_handler(), pass it the frame pointer.
226
227
208HAVE_FTRACE_NMI_ENTER 228HAVE_FTRACE_NMI_ENTER
209--------------------- 229---------------------
210 230
diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
index 8179692fbb90..bab3040da548 100644
--- a/Documentation/trace/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
@@ -1625,7 +1625,7 @@ If I am only interested in sys_nanosleep and hrtimer_interrupt:
1625 1625
1626 # echo sys_nanosleep hrtimer_interrupt \ 1626 # echo sys_nanosleep hrtimer_interrupt \
1627 > set_ftrace_filter 1627 > set_ftrace_filter
1628 # echo ftrace > current_tracer 1628 # echo function > current_tracer
1629 # echo 1 > tracing_enabled 1629 # echo 1 > tracing_enabled
1630 # usleep 1 1630 # usleep 1
1631 # echo 0 > tracing_enabled 1631 # echo 0 > tracing_enabled
diff --git a/Documentation/trace/ring-buffer-design.txt b/Documentation/trace/ring-buffer-design.txt
index 5b1d23d604c5..d299ff31df57 100644
--- a/Documentation/trace/ring-buffer-design.txt
+++ b/Documentation/trace/ring-buffer-design.txt
@@ -33,9 +33,9 @@ head_page - a pointer to the page that the reader will use next
33 33
34tail_page - a pointer to the page that will be written to next 34tail_page - a pointer to the page that will be written to next
35 35
36commit_page - a pointer to the page with the last finished non nested write. 36commit_page - a pointer to the page with the last finished non-nested write.
37 37
38cmpxchg - hardware assisted atomic transaction that performs the following: 38cmpxchg - hardware-assisted atomic transaction that performs the following:
39 39
40 A = B iff previous A == C 40 A = B iff previous A == C
41 41
@@ -52,15 +52,15 @@ The Generic Ring Buffer
52The ring buffer can be used in either an overwrite mode or in 52The ring buffer can be used in either an overwrite mode or in
53producer/consumer mode. 53producer/consumer mode.
54 54
55Producer/consumer mode is where the producer were to fill up the 55Producer/consumer mode is where if the producer were to fill up the
56buffer before the consumer could free up anything, the producer 56buffer before the consumer could free up anything, the producer
57will stop writing to the buffer. This will lose most recent events. 57will stop writing to the buffer. This will lose most recent events.
58 58
59Overwrite mode is where the produce were to fill up the buffer 59Overwrite mode is where if the producer were to fill up the buffer
60before the consumer could free up anything, the producer will 60before the consumer could free up anything, the producer will
61overwrite the older data. This will lose the oldest events. 61overwrite the older data. This will lose the oldest events.
62 62
63No two writers can write at the same time (on the same per cpu buffer), 63No two writers can write at the same time (on the same per-cpu buffer),
64but a writer may interrupt another writer, but it must finish writing 64but a writer may interrupt another writer, but it must finish writing
65before the previous writer may continue. This is very important to the 65before the previous writer may continue. This is very important to the
66algorithm. The writers act like a "stack". The way interrupts works 66algorithm. The writers act like a "stack". The way interrupts works
@@ -79,16 +79,16 @@ the interrupt doing a write as well.
79 79
80Readers can happen at any time. But no two readers may run at the 80Readers can happen at any time. But no two readers may run at the
81same time, nor can a reader preempt/interrupt another reader. A reader 81same time, nor can a reader preempt/interrupt another reader. A reader
82can not preempt/interrupt a writer, but it may read/consume from the 82cannot preempt/interrupt a writer, but it may read/consume from the
83buffer at the same time as a writer is writing, but the reader must be 83buffer at the same time as a writer is writing, but the reader must be
84on another processor to do so. A reader may read on its own processor 84on another processor to do so. A reader may read on its own processor
85and can be preempted by a writer. 85and can be preempted by a writer.
86 86
87A writer can preempt a reader, but a reader can not preempt a writer. 87A writer can preempt a reader, but a reader cannot preempt a writer.
88But a reader can read the buffer at the same time (on another processor) 88But a reader can read the buffer at the same time (on another processor)
89as a writer. 89as a writer.
90 90
91The ring buffer is made up of a list of pages held together by a link list. 91The ring buffer is made up of a list of pages held together by a linked list.
92 92
93At initialization a reader page is allocated for the reader that is not 93At initialization a reader page is allocated for the reader that is not
94part of the ring buffer. 94part of the ring buffer.
@@ -102,7 +102,7 @@ the head page.
102 102
103The reader has its own page to use. At start up time, this page is 103The reader has its own page to use. At start up time, this page is
104allocated but is not attached to the list. When the reader wants 104allocated but is not attached to the list. When the reader wants
105to read from the buffer, if its page is empty (like it is on start up) 105to read from the buffer, if its page is empty (like it is on start-up),
106it will swap its page with the head_page. The old reader page will 106it will swap its page with the head_page. The old reader page will
107become part of the ring buffer and the head_page will be removed. 107become part of the ring buffer and the head_page will be removed.
108The page after the inserted page (old reader_page) will become the 108The page after the inserted page (old reader_page) will become the
@@ -206,7 +206,7 @@ The main pointers:
206 206
207 commit page - the page that last finished a write. 207 commit page - the page that last finished a write.
208 208
209The commit page only is updated by the outer most writer in the 209The commit page only is updated by the outermost writer in the
210writer stack. A writer that preempts another writer will not move the 210writer stack. A writer that preempts another writer will not move the
211commit page. 211commit page.
212 212
@@ -281,7 +281,7 @@ with the previous write.
281The commit pointer points to the last write location that was 281The commit pointer points to the last write location that was
282committed without preempting another write. When a write that 282committed without preempting another write. When a write that
283preempted another write is committed, it only becomes a pending commit 283preempted another write is committed, it only becomes a pending commit
284and will not be a full commit till all writes have been committed. 284and will not be a full commit until all writes have been committed.
285 285
286The commit page points to the page that has the last full commit. 286The commit page points to the page that has the last full commit.
287The tail page points to the page with the last write (before 287The tail page points to the page with the last write (before
@@ -292,7 +292,7 @@ be several pages ahead. If the tail page catches up to the commit
292page then no more writes may take place (regardless of the mode 292page then no more writes may take place (regardless of the mode
293of the ring buffer: overwrite and produce/consumer). 293of the ring buffer: overwrite and produce/consumer).
294 294
295The order of pages are: 295The order of pages is:
296 296
297 head page 297 head page
298 commit page 298 commit page
@@ -311,7 +311,7 @@ Possible scenario:
311There is a special case that the head page is after either the commit page 311There is a special case that the head page is after either the commit page
312and possibly the tail page. That is when the commit (and tail) page has been 312and possibly the tail page. That is when the commit (and tail) page has been
313swapped with the reader page. This is because the head page is always 313swapped with the reader page. This is because the head page is always
314part of the ring buffer, but the reader page is not. When ever there 314part of the ring buffer, but the reader page is not. Whenever there
315has been less than a full page that has been committed inside the ring buffer, 315has been less than a full page that has been committed inside the ring buffer,
316and a reader swaps out a page, it will be swapping out the commit page. 316and a reader swaps out a page, it will be swapping out the commit page.
317 317
@@ -338,7 +338,7 @@ and a reader swaps out a page, it will be swapping out the commit page.
338In this case, the head page will not move when the tail and commit 338In this case, the head page will not move when the tail and commit
339move back into the ring buffer. 339move back into the ring buffer.
340 340
341The reader can not swap a page into the ring buffer if the commit page 341The reader cannot swap a page into the ring buffer if the commit page
342is still on that page. If the read meets the last commit (real commit 342is still on that page. If the read meets the last commit (real commit
343not pending or reserved), then there is nothing more to read. 343not pending or reserved), then there is nothing more to read.
344The buffer is considered empty until another full commit finishes. 344The buffer is considered empty until another full commit finishes.
@@ -395,7 +395,7 @@ The main idea behind the lockless algorithm is to combine the moving
395of the head_page pointer with the swapping of pages with the reader. 395of the head_page pointer with the swapping of pages with the reader.
396State flags are placed inside the pointer to the page. To do this, 396State flags are placed inside the pointer to the page. To do this,
397each page must be aligned in memory by 4 bytes. This will allow the 2 397each page must be aligned in memory by 4 bytes. This will allow the 2
398least significant bits of the address to be used as flags. Since 398least significant bits of the address to be used as flags, since
399they will always be zero for the address. To get the address, 399they will always be zero for the address. To get the address,
400simply mask out the flags. 400simply mask out the flags.
401 401
@@ -460,7 +460,7 @@ When the reader tries to swap the page with the ring buffer, it
460will also use cmpxchg. If the flag bit in the pointer to the 460will also use cmpxchg. If the flag bit in the pointer to the
461head page does not have the HEADER flag set, the compare will fail 461head page does not have the HEADER flag set, the compare will fail
462and the reader will need to look for the new head page and try again. 462and the reader will need to look for the new head page and try again.
463Note, the flag UPDATE and HEADER are never set at the same time. 463Note, the flags UPDATE and HEADER are never set at the same time.
464 464
465The reader swaps the reader page as follows: 465The reader swaps the reader page as follows:
466 466
@@ -539,7 +539,7 @@ updated to the reader page.
539 | +-----------------------------+ | 539 | +-----------------------------+ |
540 +------------------------------------+ 540 +------------------------------------+
541 541
542Another important point. The page that the reader page points back to 542Another important point: The page that the reader page points back to
543by its previous pointer (the one that now points to the new head page) 543by its previous pointer (the one that now points to the new head page)
544never points back to the reader page. That is because the reader page is 544never points back to the reader page. That is because the reader page is
545not part of the ring buffer. Traversing the ring buffer via the next pointers 545not part of the ring buffer. Traversing the ring buffer via the next pointers
@@ -572,7 +572,7 @@ not be able to swap the head page from the buffer, nor will it be able to
572move the head page, until the writer is finished with the move. 572move the head page, until the writer is finished with the move.
573 573
574This eliminates any races that the reader can have on the writer. The reader 574This eliminates any races that the reader can have on the writer. The reader
575must spin, and this is why the reader can not preempt the writer. 575must spin, and this is why the reader cannot preempt the writer.
576 576
577 tail page 577 tail page
578 | 578 |
@@ -659,9 +659,9 @@ before pushing the head page. If it is, then it can be assumed that the
659tail page wrapped the buffer, and we must drop new writes. 659tail page wrapped the buffer, and we must drop new writes.
660 660
661This is not a race condition, because the commit page can only be moved 661This is not a race condition, because the commit page can only be moved
662by the outter most writer (the writer that was preempted). 662by the outermost writer (the writer that was preempted).
663This means that the commit will not move while a writer is moving the 663This means that the commit will not move while a writer is moving the
664tail page. The reader can not swap the reader page if it is also being 664tail page. The reader cannot swap the reader page if it is also being
665used as the commit page. The reader can simply check that the commit 665used as the commit page. The reader can simply check that the commit
666is off the reader page. Once the commit page leaves the reader page 666is off the reader page. Once the commit page leaves the reader page
667it will never go back on it unless a reader does another swap with the 667it will never go back on it unless a reader does another swap with the
@@ -733,7 +733,7 @@ The write converts the head page pointer to UPDATE.
733--->| |<---| |<---| |<---| |<--- 733--->| |<---| |<---| |<---| |<---
734 +---+ +---+ +---+ +---+ 734 +---+ +---+ +---+ +---+
735 735
736But if a nested writer preempts here. It will see that the next 736But if a nested writer preempts here, it will see that the next
737page is a head page, but it is also nested. It will detect that 737page is a head page, but it is also nested. It will detect that
738it is nested and will save that information. The detection is the 738it is nested and will save that information. The detection is the
739fact that it sees the UPDATE flag instead of a HEADER or NORMAL 739fact that it sees the UPDATE flag instead of a HEADER or NORMAL
@@ -761,7 +761,7 @@ to NORMAL.
761--->| |<---| |<---| |<---| |<--- 761--->| |<---| |<---| |<---| |<---
762 +---+ +---+ +---+ +---+ 762 +---+ +---+ +---+ +---+
763 763
764After the nested writer finishes, the outer most writer will convert 764After the nested writer finishes, the outermost writer will convert
765the UPDATE pointer to NORMAL. 765the UPDATE pointer to NORMAL.
766 766
767 767
@@ -812,7 +812,7 @@ head page.
812 +---+ +---+ +---+ +---+ 812 +---+ +---+ +---+ +---+
813 813
814The nested writer moves the tail page forward. But does not set the old 814The nested writer moves the tail page forward. But does not set the old
815update page to NORMAL because it is not the outer most writer. 815update page to NORMAL because it is not the outermost writer.
816 816
817 tail page 817 tail page
818 | 818 |
@@ -892,7 +892,7 @@ It will return to the first writer.
892--->| |<---| |<---| |<---| |<--- 892--->| |<---| |<---| |<---| |<---
893 +---+ +---+ +---+ +---+ 893 +---+ +---+ +---+ +---+
894 894
895The first writer can not know atomically test if the tail page moved 895The first writer cannot know atomically if the tail page moved
896while it updates the HEAD page. It will then update the head page to 896while it updates the HEAD page. It will then update the head page to
897what it thinks is the new head page. 897what it thinks is the new head page.
898 898
@@ -923,9 +923,9 @@ if the tail page is either where it use to be or on the next page:
923--->| |<---| |<---| |<---| |<--- 923--->| |<---| |<---| |<---| |<---
924 +---+ +---+ +---+ +---+ 924 +---+ +---+ +---+ +---+
925 925
926If tail page != A and tail page does not equal B, then it must reset the 926If tail page != A and tail page != B, then it must reset the pointer
927pointer back to NORMAL. The fact that it only needs to worry about 927back to NORMAL. The fact that it only needs to worry about nested
928nested writers, it only needs to check this after setting the HEAD page. 928writers means that it only needs to check this after setting the HEAD page.
929 929
930 930
931(first writer) 931(first writer)
@@ -939,7 +939,7 @@ nested writers, it only needs to check this after setting the HEAD page.
939 +---+ +---+ +---+ +---+ 939 +---+ +---+ +---+ +---+
940 940
941Now the writer can update the head page. This is also why the head page must 941Now the writer can update the head page. This is also why the head page must
942remain in UPDATE and only reset by the outer most writer. This prevents 942remain in UPDATE and only reset by the outermost writer. This prevents
943the reader from seeing the incorrect head page. 943the reader from seeing the incorrect head page.
944 944
945 945