diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/filesystems/proc.txt | 2 | ||||
-rw-r--r-- | Documentation/hwmon/amc6821 | 102 | ||||
-rw-r--r-- | Documentation/ioctl/ioctl-number.txt | 203 | ||||
-rw-r--r-- | Documentation/kernel-doc-nano-HOWTO.txt | 12 | ||||
-rw-r--r-- | Documentation/trace/ring-buffer-design.txt | 56 |
5 files changed, 296 insertions, 79 deletions
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 | ||
182 | This shows you nearly the same information you would get if you viewed it with | 181 | This shows you nearly the same information you would get if you viewed it with |
183 | the ps command. In fact, ps uses the proc file system to obtain its | 182 | the 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 | ||
237 | Table 1-3: Contents of the statm files (as of 2.6.8-rc3) | 235 | Table 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 @@ | |||
1 | Kernel driver amc6821 | ||
2 | ===================== | ||
3 | |||
4 | Supported 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 | |||
10 | Authors: | ||
11 | Tomaz Mertelj <tomaz.mertelj@guest.arnes.si> | ||
12 | |||
13 | |||
14 | Description | ||
15 | ----------- | ||
16 | |||
17 | This driver implements support for the Texas Instruments amc6821 chip. | ||
18 | The chip has one on-chip and one remote temperature sensor and one pwm fan | ||
19 | regulator. | ||
20 | The pwm can be controlled either from software or automatically. | ||
21 | |||
22 | The driver provides the following sensor accesses in sysfs: | ||
23 | |||
24 | temp1_input ro on-chip temperature | ||
25 | temp1_min rw " | ||
26 | temp1_max rw " | ||
27 | temp1_crit rw " | ||
28 | temp1_min_alarm ro " | ||
29 | temp1_max_alarm ro " | ||
30 | temp1_crit_alarm ro " | ||
31 | |||
32 | temp2_input ro remote temperature | ||
33 | temp2_min rw " | ||
34 | temp2_max rw " | ||
35 | temp2_crit rw " | ||
36 | temp2_min_alarm ro " | ||
37 | temp2_max_alarm ro " | ||
38 | temp2_crit_alarm ro " | ||
39 | temp2_fault ro " | ||
40 | |||
41 | fan1_input ro tachometer speed | ||
42 | fan1_min rw " | ||
43 | fan1_max rw " | ||
44 | fan1_fault ro " | ||
45 | fan1_div rw Fan divisor can be either 2 or 4. | ||
46 | |||
47 | pwm1 rw pwm1 | ||
48 | pwm1_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, | ||
52 | pwm1_auto_channels_temp ro 1 if pwm_enable==2, 3 if pwm_enable==3 | ||
53 | pwm1_auto_point1_pwm ro Hardwired to 0, shared for both | ||
54 | temperature channels. | ||
55 | pwm1_auto_point2_pwm rw This value is shared for both temperature | ||
56 | channels. | ||
57 | pwm1_auto_point3_pwm rw Hardwired to 255, shared for both | ||
58 | temperature channels. | ||
59 | |||
60 | temp1_auto_point1_temp ro Hardwired to temp2_auto_point1_temp | ||
61 | which is rw. Below this temperature fan stops. | ||
62 | temp1_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. | ||
68 | temp1_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 | |||
75 | temp2_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. | ||
79 | temp2_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 | |||
85 | temp2_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 | |||
92 | Module parameters | ||
93 | ----------------- | ||
94 | |||
95 | If your board has a BIOS that initializes the amc6821 correctly, you should | ||
96 | load the module with: init=0. | ||
97 | |||
98 | If your board BIOS doesn't initialize the chip, or you want | ||
99 | different settings, you can set the following parameters: | ||
100 | init=1, | ||
101 | pwminv: 0 default pwm output, 1 inverts pwm output. | ||
102 | |||
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 | ||
59 | This table lists ioctls visible from user land for Linux/i386. It contains | 59 | This table lists ioctls visible from user land for Linux/x86. It contains |
60 | most drivers up to 2.3.14, but I know I am missing some. | 60 | most drivers up to 2.6.31, but I know I am missing some. There has been |
61 | no attempt to list non-X86 architectures or ioctls from drivers/staging/. | ||
61 | 62 | ||
62 | Code Seq# Include File Comments | 63 | Code Seq#(hex) Include File Comments |
63 | ======================================================== | 64 | ======================================================== |
64 | 0x00 00-1F linux/fs.h conflict! | 65 | 0x00 00-1F linux/fs.h conflict! |
65 | 0x00 00-1F scsi/scsi_ioctl.h conflict! | 66 | 0x00 00-1F scsi/scsi_ioctl.h conflict! |
@@ -69,119 +70,228 @@ Code Seq# Include File Comments | |||
69 | 0x03 all linux/hdreg.h | 70 | 0x03 all linux/hdreg.h |
70 | 0x04 D2-DC linux/umsdos_fs.h Dead since 2.6.11, but don't reuse these. | 71 | 0x04 D2-DC linux/umsdos_fs.h Dead since 2.6.11, but don't reuse these. |
71 | 0x06 all linux/lp.h | 72 | 0x06 all linux/lp.h |
72 | 0x09 all linux/md.h | 73 | 0x09 all linux/raid/md_u.h |
74 | 0x10 00-0F drivers/char/s390/vmcp.h | ||
73 | 0x12 all linux/fs.h | 75 | 0x12 all linux/fs.h |
74 | linux/blkpg.h | 76 | linux/blkpg.h |
75 | 0x1b all InfiniBand Subsystem <http://www.openib.org/> | 77 | 0x1b all InfiniBand Subsystem <http://www.openib.org/> |
76 | 0x20 all drivers/cdrom/cm206.h | 78 | 0x20 all drivers/cdrom/cm206.h |
77 | 0x22 all scsi/sg.h | 79 | 0x22 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! | ||
174 | 0x80 00-1F linux/fb.h | 280 | 0x80 00-1F linux/fb.h |
175 | 0x81 00-1F linux/videotext.h | 281 | 0x81 00-1F linux/videotext.h |
282 | 0x88 00-3F media/ovcamchip.h | ||
176 | 0x89 00-06 arch/x86/include/asm/sockios.h | 283 | 0x89 00-06 arch/x86/include/asm/sockios.h |
177 | 0x89 0B-DF linux/sockios.h | 284 | 0x89 0B-DF linux/sockios.h |
178 | 0x89 E0-EF linux/sockios.h SIOCPROTOPRIVATE range | 285 | 0x89 E0-EF linux/sockios.h SIOCPROTOPRIVATE range |
286 | 0x89 E0-EF linux/dn.h PROTOPRIVATE range | ||
179 | 0x89 F0-FF linux/sockios.h SIOCDEVPRIVATE range | 287 | 0x89 F0-FF linux/sockios.h SIOCDEVPRIVATE range |
180 | 0x8B all linux/wireless.h | 288 | 0x8B all linux/wireless.h |
181 | 0x8C 00-3F WiNRADiO driver | 289 | 0x8C 00-3F WiNRADiO driver |
182 | <http://www.proximity.com.au/~brian/winradio/> | 290 | <http://www.proximity.com.au/~brian/winradio/> |
183 | 0x90 00 drivers/cdrom/sbpcd.h | 291 | 0x90 00 drivers/cdrom/sbpcd.h |
292 | 0x92 00-0F drivers/usb/mon/mon_bin.c | ||
184 | 0x93 60-7F linux/auto_fs.h | 293 | 0x93 60-7F linux/auto_fs.h |
294 | 0x94 all fs/btrfs/ioctl.h | ||
185 | 0x99 00-0F 537-Addinboard driver | 295 | 0x99 00-0F 537-Addinboard driver |
186 | <mailto:buk@buks.ipn.de> | 296 | <mailto:buk@buks.ipn.de> |
187 | 0xA0 all linux/sdp/sdp.h Industrial Device Project | 297 | 0xA0 all linux/sdp/sdp.h Industrial Device Project |
@@ -192,17 +302,22 @@ Code Seq# Include File Comments | |||
192 | 0xAB 00-1F linux/nbd.h | 302 | 0xAB 00-1F linux/nbd.h |
193 | 0xAC 00-1F linux/raw.h | 303 | 0xAC 00-1F linux/raw.h |
194 | 0xAD 00 Netfilter device in development: | 304 | 0xAD 00 Netfilter device in development: |
195 | <mailto:rusty@rustcorp.com.au> | 305 | <mailto:rusty@rustcorp.com.au> |
196 | 0xAE all linux/kvm.h Kernel-based Virtual Machine | 306 | 0xAE all linux/kvm.h Kernel-based Virtual Machine |
197 | <mailto:kvm@vger.kernel.org> | 307 | <mailto:kvm@vger.kernel.org> |
198 | 0xB0 all RATIO devices in development: | 308 | 0xB0 all RATIO devices in development: |
199 | <mailto:vgo@ratio.de> | 309 | <mailto:vgo@ratio.de> |
200 | 0xB1 00-1F PPPoX <mailto:mostrows@styx.uwaterloo.ca> | 310 | 0xB1 00-1F PPPoX <mailto:mostrows@styx.uwaterloo.ca> |
311 | 0xC0 00-0F linux/usb/iowarrior.h | ||
201 | 0xCB 00-1F CBM serial IEC bus in development: | 312 | 0xCB 00-1F CBM serial IEC bus in development: |
202 | <mailto:michael.klein@puffin.lb.shuttle.de> | 313 | <mailto:michael.klein@puffin.lb.shuttle.de> |
314 | 0xCD 01 linux/reiserfs_fs.h | ||
315 | 0xCF 02 fs/cifs/ioctl.c | ||
316 | 0xDB 00-0F drivers/char/mwave/mwavepub.h | ||
203 | 0xDD 00-3F ZFCP device driver see drivers/s390/scsi/ | 317 | 0xDD 00-3F ZFCP device driver see drivers/s390/scsi/ |
204 | <mailto:aherrman@de.ibm.com> | 318 | <mailto:aherrman@de.ibm.com> |
205 | 0xF3 00-3F video/sisfb.h sisfb (in development) | 319 | 0xF3 00-3F drivers/usb/misc/sisusbvga/sisusb.h sisfb (in development) |
206 | <mailto:thomas@winischhofer.net> | 320 | <mailto:thomas@winischhofer.net> |
207 | 0xF4 00-1F video/mbxfb.h mbxfb | 321 | 0xF4 00-1F video/mbxfb.h mbxfb |
208 | <mailto:raph@8d.com> | 322 | <mailto:raph@8d.com> |
323 | 0xFD 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 | ||
217 | The short function description ***cannot be multiline***, but the other | 217 | All "description" text can span multiple lines, although the |
218 | descriptions can be (and they can contain blank lines). If you continue | 218 | function_name & its short description are traditionally on a single line. |
219 | that initial short description onto a second line, that second line will | 219 | Description text may also contain blank lines (i.e., lines that contain |
220 | appear further down at the beginning of the description section, which is | 220 | only a "*"). |
221 | almost certainly not what you had in mind. | 221 | |
222 | "section header:" names must be unique per function (or struct, | ||
223 | union, typedef, enum). | ||
222 | 224 | ||
223 | Avoid putting a spurious blank line after the function name, or else the | 225 | Avoid putting a spurious blank line after the function name, or else the |
224 | description will be repeated! | 226 | description will be repeated! |
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 | ||
34 | tail_page - a pointer to the page that will be written to next | 34 | tail_page - a pointer to the page that will be written to next |
35 | 35 | ||
36 | commit_page - a pointer to the page with the last finished non nested write. | 36 | commit_page - a pointer to the page with the last finished non-nested write. |
37 | 37 | ||
38 | cmpxchg - hardware assisted atomic transaction that performs the following: | 38 | cmpxchg - 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 | |||
52 | The ring buffer can be used in either an overwrite mode or in | 52 | The ring buffer can be used in either an overwrite mode or in |
53 | producer/consumer mode. | 53 | producer/consumer mode. |
54 | 54 | ||
55 | Producer/consumer mode is where the producer were to fill up the | 55 | Producer/consumer mode is where if the producer were to fill up the |
56 | buffer before the consumer could free up anything, the producer | 56 | buffer before the consumer could free up anything, the producer |
57 | will stop writing to the buffer. This will lose most recent events. | 57 | will stop writing to the buffer. This will lose most recent events. |
58 | 58 | ||
59 | Overwrite mode is where the produce were to fill up the buffer | 59 | Overwrite mode is where if the producer were to fill up the buffer |
60 | before the consumer could free up anything, the producer will | 60 | before the consumer could free up anything, the producer will |
61 | overwrite the older data. This will lose the oldest events. | 61 | overwrite the older data. This will lose the oldest events. |
62 | 62 | ||
63 | No two writers can write at the same time (on the same per cpu buffer), | 63 | No two writers can write at the same time (on the same per-cpu buffer), |
64 | but a writer may interrupt another writer, but it must finish writing | 64 | but a writer may interrupt another writer, but it must finish writing |
65 | before the previous writer may continue. This is very important to the | 65 | before the previous writer may continue. This is very important to the |
66 | algorithm. The writers act like a "stack". The way interrupts works | 66 | algorithm. The writers act like a "stack". The way interrupts works |
@@ -79,16 +79,16 @@ the interrupt doing a write as well. | |||
79 | 79 | ||
80 | Readers can happen at any time. But no two readers may run at the | 80 | Readers can happen at any time. But no two readers may run at the |
81 | same time, nor can a reader preempt/interrupt another reader. A reader | 81 | same time, nor can a reader preempt/interrupt another reader. A reader |
82 | can not preempt/interrupt a writer, but it may read/consume from the | 82 | cannot preempt/interrupt a writer, but it may read/consume from the |
83 | buffer at the same time as a writer is writing, but the reader must be | 83 | buffer at the same time as a writer is writing, but the reader must be |
84 | on another processor to do so. A reader may read on its own processor | 84 | on another processor to do so. A reader may read on its own processor |
85 | and can be preempted by a writer. | 85 | and can be preempted by a writer. |
86 | 86 | ||
87 | A writer can preempt a reader, but a reader can not preempt a writer. | 87 | A writer can preempt a reader, but a reader cannot preempt a writer. |
88 | But a reader can read the buffer at the same time (on another processor) | 88 | But a reader can read the buffer at the same time (on another processor) |
89 | as a writer. | 89 | as a writer. |
90 | 90 | ||
91 | The ring buffer is made up of a list of pages held together by a link list. | 91 | The ring buffer is made up of a list of pages held together by a linked list. |
92 | 92 | ||
93 | At initialization a reader page is allocated for the reader that is not | 93 | At initialization a reader page is allocated for the reader that is not |
94 | part of the ring buffer. | 94 | part of the ring buffer. |
@@ -102,7 +102,7 @@ the head page. | |||
102 | 102 | ||
103 | The reader has its own page to use. At start up time, this page is | 103 | The reader has its own page to use. At start up time, this page is |
104 | allocated but is not attached to the list. When the reader wants | 104 | allocated but is not attached to the list. When the reader wants |
105 | to read from the buffer, if its page is empty (like it is on start up) | 105 | to read from the buffer, if its page is empty (like it is on start-up), |
106 | it will swap its page with the head_page. The old reader page will | 106 | it will swap its page with the head_page. The old reader page will |
107 | become part of the ring buffer and the head_page will be removed. | 107 | become part of the ring buffer and the head_page will be removed. |
108 | The page after the inserted page (old reader_page) will become the | 108 | The 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 | ||
209 | The commit page only is updated by the outer most writer in the | 209 | The commit page only is updated by the outermost writer in the |
210 | writer stack. A writer that preempts another writer will not move the | 210 | writer stack. A writer that preempts another writer will not move the |
211 | commit page. | 211 | commit page. |
212 | 212 | ||
@@ -281,7 +281,7 @@ with the previous write. | |||
281 | The commit pointer points to the last write location that was | 281 | The commit pointer points to the last write location that was |
282 | committed without preempting another write. When a write that | 282 | committed without preempting another write. When a write that |
283 | preempted another write is committed, it only becomes a pending commit | 283 | preempted another write is committed, it only becomes a pending commit |
284 | and will not be a full commit till all writes have been committed. | 284 | and will not be a full commit until all writes have been committed. |
285 | 285 | ||
286 | The commit page points to the page that has the last full commit. | 286 | The commit page points to the page that has the last full commit. |
287 | The tail page points to the page with the last write (before | 287 | The 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 | |||
292 | page then no more writes may take place (regardless of the mode | 292 | page then no more writes may take place (regardless of the mode |
293 | of the ring buffer: overwrite and produce/consumer). | 293 | of the ring buffer: overwrite and produce/consumer). |
294 | 294 | ||
295 | The order of pages are: | 295 | The order of pages is: |
296 | 296 | ||
297 | head page | 297 | head page |
298 | commit page | 298 | commit page |
@@ -311,7 +311,7 @@ Possible scenario: | |||
311 | There is a special case that the head page is after either the commit page | 311 | There is a special case that the head page is after either the commit page |
312 | and possibly the tail page. That is when the commit (and tail) page has been | 312 | and possibly the tail page. That is when the commit (and tail) page has been |
313 | swapped with the reader page. This is because the head page is always | 313 | swapped with the reader page. This is because the head page is always |
314 | part of the ring buffer, but the reader page is not. When ever there | 314 | part of the ring buffer, but the reader page is not. Whenever there |
315 | has been less than a full page that has been committed inside the ring buffer, | 315 | has been less than a full page that has been committed inside the ring buffer, |
316 | and a reader swaps out a page, it will be swapping out the commit page. | 316 | and 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. | |||
338 | In this case, the head page will not move when the tail and commit | 338 | In this case, the head page will not move when the tail and commit |
339 | move back into the ring buffer. | 339 | move back into the ring buffer. |
340 | 340 | ||
341 | The reader can not swap a page into the ring buffer if the commit page | 341 | The reader cannot swap a page into the ring buffer if the commit page |
342 | is still on that page. If the read meets the last commit (real commit | 342 | is still on that page. If the read meets the last commit (real commit |
343 | not pending or reserved), then there is nothing more to read. | 343 | not pending or reserved), then there is nothing more to read. |
344 | The buffer is considered empty until another full commit finishes. | 344 | The 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 | |||
395 | of the head_page pointer with the swapping of pages with the reader. | 395 | of the head_page pointer with the swapping of pages with the reader. |
396 | State flags are placed inside the pointer to the page. To do this, | 396 | State flags are placed inside the pointer to the page. To do this, |
397 | each page must be aligned in memory by 4 bytes. This will allow the 2 | 397 | each page must be aligned in memory by 4 bytes. This will allow the 2 |
398 | least significant bits of the address to be used as flags. Since | 398 | least significant bits of the address to be used as flags, since |
399 | they will always be zero for the address. To get the address, | 399 | they will always be zero for the address. To get the address, |
400 | simply mask out the flags. | 400 | simply mask out the flags. |
401 | 401 | ||
@@ -460,7 +460,7 @@ When the reader tries to swap the page with the ring buffer, it | |||
460 | will also use cmpxchg. If the flag bit in the pointer to the | 460 | will also use cmpxchg. If the flag bit in the pointer to the |
461 | head page does not have the HEADER flag set, the compare will fail | 461 | head page does not have the HEADER flag set, the compare will fail |
462 | and the reader will need to look for the new head page and try again. | 462 | and the reader will need to look for the new head page and try again. |
463 | Note, the flag UPDATE and HEADER are never set at the same time. | 463 | Note, the flags UPDATE and HEADER are never set at the same time. |
464 | 464 | ||
465 | The reader swaps the reader page as follows: | 465 | The reader swaps the reader page as follows: |
466 | 466 | ||
@@ -539,7 +539,7 @@ updated to the reader page. | |||
539 | | +-----------------------------+ | | 539 | | +-----------------------------+ | |
540 | +------------------------------------+ | 540 | +------------------------------------+ |
541 | 541 | ||
542 | Another important point. The page that the reader page points back to | 542 | Another important point: The page that the reader page points back to |
543 | by its previous pointer (the one that now points to the new head page) | 543 | by its previous pointer (the one that now points to the new head page) |
544 | never points back to the reader page. That is because the reader page is | 544 | never points back to the reader page. That is because the reader page is |
545 | not part of the ring buffer. Traversing the ring buffer via the next pointers | 545 | not 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 | |||
572 | move the head page, until the writer is finished with the move. | 572 | move the head page, until the writer is finished with the move. |
573 | 573 | ||
574 | This eliminates any races that the reader can have on the writer. The reader | 574 | This eliminates any races that the reader can have on the writer. The reader |
575 | must spin, and this is why the reader can not preempt the writer. | 575 | must 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 | |||
659 | tail page wrapped the buffer, and we must drop new writes. | 659 | tail page wrapped the buffer, and we must drop new writes. |
660 | 660 | ||
661 | This is not a race condition, because the commit page can only be moved | 661 | This is not a race condition, because the commit page can only be moved |
662 | by the outter most writer (the writer that was preempted). | 662 | by the outermost writer (the writer that was preempted). |
663 | This means that the commit will not move while a writer is moving the | 663 | This means that the commit will not move while a writer is moving the |
664 | tail page. The reader can not swap the reader page if it is also being | 664 | tail page. The reader cannot swap the reader page if it is also being |
665 | used as the commit page. The reader can simply check that the commit | 665 | used as the commit page. The reader can simply check that the commit |
666 | is off the reader page. Once the commit page leaves the reader page | 666 | is off the reader page. Once the commit page leaves the reader page |
667 | it will never go back on it unless a reader does another swap with the | 667 | it 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 | ||
736 | But if a nested writer preempts here. It will see that the next | 736 | But if a nested writer preempts here, it will see that the next |
737 | page is a head page, but it is also nested. It will detect that | 737 | page is a head page, but it is also nested. It will detect that |
738 | it is nested and will save that information. The detection is the | 738 | it is nested and will save that information. The detection is the |
739 | fact that it sees the UPDATE flag instead of a HEADER or NORMAL | 739 | fact that it sees the UPDATE flag instead of a HEADER or NORMAL |
@@ -761,7 +761,7 @@ to NORMAL. | |||
761 | --->| |<---| |<---| |<---| |<--- | 761 | --->| |<---| |<---| |<---| |<--- |
762 | +---+ +---+ +---+ +---+ | 762 | +---+ +---+ +---+ +---+ |
763 | 763 | ||
764 | After the nested writer finishes, the outer most writer will convert | 764 | After the nested writer finishes, the outermost writer will convert |
765 | the UPDATE pointer to NORMAL. | 765 | the UPDATE pointer to NORMAL. |
766 | 766 | ||
767 | 767 | ||
@@ -812,7 +812,7 @@ head page. | |||
812 | +---+ +---+ +---+ +---+ | 812 | +---+ +---+ +---+ +---+ |
813 | 813 | ||
814 | The nested writer moves the tail page forward. But does not set the old | 814 | The nested writer moves the tail page forward. But does not set the old |
815 | update page to NORMAL because it is not the outer most writer. | 815 | update 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 | ||
895 | The first writer can not know atomically test if the tail page moved | 895 | The first writer cannot know atomically if the tail page moved |
896 | while it updates the HEAD page. It will then update the head page to | 896 | while it updates the HEAD page. It will then update the head page to |
897 | what it thinks is the new head page. | 897 | what 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 | ||
926 | If tail page != A and tail page does not equal B, then it must reset the | 926 | If tail page != A and tail page != B, then it must reset the pointer |
927 | pointer back to NORMAL. The fact that it only needs to worry about | 927 | back to NORMAL. The fact that it only needs to worry about nested |
928 | nested writers, it only needs to check this after setting the HEAD page. | 928 | writers 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 | ||
941 | Now the writer can update the head page. This is also why the head page must | 941 | Now the writer can update the head page. This is also why the head page must |
942 | remain in UPDATE and only reset by the outer most writer. This prevents | 942 | remain in UPDATE and only reset by the outermost writer. This prevents |
943 | the reader from seeing the incorrect head page. | 943 | the reader from seeing the incorrect head page. |
944 | 944 | ||
945 | 945 | ||