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-rw-r--r--Documentation/ABI/testing/sysfs-fs-ext410
-rw-r--r--Documentation/ABI/testing/sysfs-pps73
-rw-r--r--Documentation/Changes7
-rw-r--r--Documentation/cgroups/memory.txt16
-rw-r--r--Documentation/connector/cn_test.c7
-rw-r--r--Documentation/feature-removal-schedule.txt14
-rw-r--r--Documentation/filesystems/ext2.txt2
-rw-r--r--Documentation/filesystems/ext4.txt4
-rw-r--r--Documentation/filesystems/isofs.txt9
-rw-r--r--Documentation/filesystems/proc.txt268
-rw-r--r--Documentation/gcov.txt246
-rw-r--r--Documentation/ioctl/ioctl-number.txt2
-rw-r--r--Documentation/kernel-parameters.txt7
-rw-r--r--Documentation/pps/pps.txt172
-rw-r--r--Documentation/rfkill.txt137
-rw-r--r--Documentation/robust-futex-ABI.txt4
-rw-r--r--Documentation/watchdog/hpwdt.txt84
17 files changed, 932 insertions, 130 deletions
diff --git a/Documentation/ABI/testing/sysfs-fs-ext4 b/Documentation/ABI/testing/sysfs-fs-ext4
index 4e79074de282..5fb709997d96 100644
--- a/Documentation/ABI/testing/sysfs-fs-ext4
+++ b/Documentation/ABI/testing/sysfs-fs-ext4
@@ -79,3 +79,13 @@ Description:
79 This file is read-only and shows the number of 79 This file is read-only and shows the number of
80 kilobytes of data that have been written to this 80 kilobytes of data that have been written to this
81 filesystem since it was mounted. 81 filesystem since it was mounted.
82
83What: /sys/fs/ext4/<disk>/inode_goal
84Date: June 2008
85Contact: "Theodore Ts'o" <tytso@mit.edu>
86Description:
87 Tuning parameter which (if non-zero) controls the goal
88 inode used by the inode allocator in p0reference to
89 all other allocation hueristics. This is intended for
90 debugging use only, and should be 0 on production
91 systems.
diff --git a/Documentation/ABI/testing/sysfs-pps b/Documentation/ABI/testing/sysfs-pps
new file mode 100644
index 000000000000..25028c7bc37d
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-pps
@@ -0,0 +1,73 @@
1What: /sys/class/pps/
2Date: February 2008
3Contact: Rodolfo Giometti <giometti@linux.it>
4Description:
5 The /sys/class/pps/ directory will contain files and
6 directories that will provide a unified interface to
7 the PPS sources.
8
9What: /sys/class/pps/ppsX/
10Date: February 2008
11Contact: Rodolfo Giometti <giometti@linux.it>
12Description:
13 The /sys/class/pps/ppsX/ directory is related to X-th
14 PPS source into the system. Each directory will
15 contain files to manage and control its PPS source.
16
17What: /sys/class/pps/ppsX/assert
18Date: February 2008
19Contact: Rodolfo Giometti <giometti@linux.it>
20Description:
21 The /sys/class/pps/ppsX/assert file reports the assert events
22 and the assert sequence number of the X-th source in the form:
23
24 <secs>.<nsec>#<sequence>
25
26 If the source has no assert events the content of this file
27 is empty.
28
29What: /sys/class/pps/ppsX/clear
30Date: February 2008
31Contact: Rodolfo Giometti <giometti@linux.it>
32Description:
33 The /sys/class/pps/ppsX/clear file reports the clear events
34 and the clear sequence number of the X-th source in the form:
35
36 <secs>.<nsec>#<sequence>
37
38 If the source has no clear events the content of this file
39 is empty.
40
41What: /sys/class/pps/ppsX/mode
42Date: February 2008
43Contact: Rodolfo Giometti <giometti@linux.it>
44Description:
45 The /sys/class/pps/ppsX/mode file reports the functioning
46 mode of the X-th source in hexadecimal encoding.
47
48 Please, refer to linux/include/linux/pps.h for further
49 info.
50
51What: /sys/class/pps/ppsX/echo
52Date: February 2008
53Contact: Rodolfo Giometti <giometti@linux.it>
54Description:
55 The /sys/class/pps/ppsX/echo file reports if the X-th does
56 or does not support an "echo" function.
57
58What: /sys/class/pps/ppsX/name
59Date: February 2008
60Contact: Rodolfo Giometti <giometti@linux.it>
61Description:
62 The /sys/class/pps/ppsX/name file reports the name of the
63 X-th source.
64
65What: /sys/class/pps/ppsX/path
66Date: February 2008
67Contact: Rodolfo Giometti <giometti@linux.it>
68Description:
69 The /sys/class/pps/ppsX/path file reports the path name of
70 the device connected with the X-th source.
71
72 If the source is not connected with any device the content
73 of this file is empty.
diff --git a/Documentation/Changes b/Documentation/Changes
index 664392481c84..6d0f1efc5bf6 100644
--- a/Documentation/Changes
+++ b/Documentation/Changes
@@ -72,6 +72,13 @@ assembling the 16-bit boot code, removing the need for as86 to compile
72your kernel. This change does, however, mean that you need a recent 72your kernel. This change does, however, mean that you need a recent
73release of binutils. 73release of binutils.
74 74
75Perl
76----
77
78You will need perl 5 and the following modules: Getopt::Long, Getopt::Std,
79File::Basename, and File::Find to build the kernel.
80
81
75System utilities 82System utilities
76================ 83================
77 84
diff --git a/Documentation/cgroups/memory.txt b/Documentation/cgroups/memory.txt
index 1a608877b14e..23d1262c0775 100644
--- a/Documentation/cgroups/memory.txt
+++ b/Documentation/cgroups/memory.txt
@@ -152,14 +152,19 @@ When swap is accounted, following files are added.
152 152
153usage of mem+swap is limited by memsw.limit_in_bytes. 153usage of mem+swap is limited by memsw.limit_in_bytes.
154 154
155Note: why 'mem+swap' rather than swap. 155* why 'mem+swap' rather than swap.
156The global LRU(kswapd) can swap out arbitrary pages. Swap-out means 156The global LRU(kswapd) can swap out arbitrary pages. Swap-out means
157to move account from memory to swap...there is no change in usage of 157to move account from memory to swap...there is no change in usage of
158mem+swap. 158mem+swap. In other words, when we want to limit the usage of swap without
159affecting global LRU, mem+swap limit is better than just limiting swap from
160OS point of view.
159 161
160In other words, when we want to limit the usage of swap without affecting 162* What happens when a cgroup hits memory.memsw.limit_in_bytes
161global LRU, mem+swap limit is better than just limiting swap from OS point 163When a cgroup his memory.memsw.limit_in_bytes, it's useless to do swap-out
162of view. 164in this cgroup. Then, swap-out will not be done by cgroup routine and file
165caches are dropped. But as mentioned above, global LRU can do swapout memory
166from it for sanity of the system's memory management state. You can't forbid
167it by cgroup.
163 168
1642.5 Reclaim 1692.5 Reclaim
165 170
@@ -204,6 +209,7 @@ We can alter the memory limit:
204 209
205NOTE: We can use a suffix (k, K, m, M, g or G) to indicate values in kilo, 210NOTE: We can use a suffix (k, K, m, M, g or G) to indicate values in kilo,
206mega or gigabytes. 211mega or gigabytes.
212NOTE: We can write "-1" to reset the *.limit_in_bytes(unlimited).
207 213
208# cat /cgroups/0/memory.limit_in_bytes 214# cat /cgroups/0/memory.limit_in_bytes
2094194304 2154194304
diff --git a/Documentation/connector/cn_test.c b/Documentation/connector/cn_test.c
index 6977c178729a..f688eba87704 100644
--- a/Documentation/connector/cn_test.c
+++ b/Documentation/connector/cn_test.c
@@ -41,6 +41,12 @@ void cn_test_callback(void *data)
41 msg->seq, msg->ack, msg->len, (char *)msg->data); 41 msg->seq, msg->ack, msg->len, (char *)msg->data);
42} 42}
43 43
44/*
45 * Do not remove this function even if no one is using it as
46 * this is an example of how to get notifications about new
47 * connector user registration
48 */
49#if 0
44static int cn_test_want_notify(void) 50static int cn_test_want_notify(void)
45{ 51{
46 struct cn_ctl_msg *ctl; 52 struct cn_ctl_msg *ctl;
@@ -117,6 +123,7 @@ nlmsg_failure:
117 kfree_skb(skb); 123 kfree_skb(skb);
118 return -EINVAL; 124 return -EINVAL;
119} 125}
126#endif
120 127
121static u32 cn_test_timer_counter; 128static u32 cn_test_timer_counter;
122static void cn_test_timer_func(unsigned long __data) 129static void cn_test_timer_func(unsigned long __data)
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index 7129846a2785..8d07ed31207e 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -6,6 +6,20 @@ be removed from this file.
6 6
7--------------------------- 7---------------------------
8 8
9What: IRQF_SAMPLE_RANDOM
10Check: IRQF_SAMPLE_RANDOM
11When: July 2009
12
13Why: Many of IRQF_SAMPLE_RANDOM users are technically bogus as entropy
14 sources in the kernel's current entropy model. To resolve this, every
15 input point to the kernel's entropy pool needs to better document the
16 type of entropy source it actually is. This will be replaced with
17 additional add_*_randomness functions in drivers/char/random.c
18
19Who: Robin Getz <rgetz@blackfin.uclinux.org> & Matt Mackall <mpm@selenic.com>
20
21---------------------------
22
9What: The ieee80211_regdom module parameter 23What: The ieee80211_regdom module parameter
10When: March 2010 / desktop catchup 24When: March 2010 / desktop catchup
11 25
diff --git a/Documentation/filesystems/ext2.txt b/Documentation/filesystems/ext2.txt
index e055acb6b2d4..67639f905f10 100644
--- a/Documentation/filesystems/ext2.txt
+++ b/Documentation/filesystems/ext2.txt
@@ -322,7 +322,7 @@ an upper limit on the block size imposed by the page size of the kernel,
322so 8kB blocks are only allowed on Alpha systems (and other architectures 322so 8kB blocks are only allowed on Alpha systems (and other architectures
323which support larger pages). 323which support larger pages).
324 324
325There is an upper limit of 32768 subdirectories in a single directory. 325There is an upper limit of 32000 subdirectories in a single directory.
326 326
327There is a "soft" upper limit of about 10-15k files in a single directory 327There is a "soft" upper limit of about 10-15k files in a single directory
328with the current linear linked-list directory implementation. This limit 328with the current linear linked-list directory implementation. This limit
diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt
index 608fdba97b72..7be02ac5fa36 100644
--- a/Documentation/filesystems/ext4.txt
+++ b/Documentation/filesystems/ext4.txt
@@ -235,6 +235,10 @@ minixdf Make 'df' act like Minix.
235 235
236debug Extra debugging information is sent to syslog. 236debug Extra debugging information is sent to syslog.
237 237
238abort Simulate the effects of calling ext4_abort() for
239 debugging purposes. This is normally used while
240 remounting a filesystem which is already mounted.
241
238errors=remount-ro Remount the filesystem read-only on an error. 242errors=remount-ro Remount the filesystem read-only on an error.
239errors=continue Keep going on a filesystem error. 243errors=continue Keep going on a filesystem error.
240errors=panic Panic and halt the machine if an error occurs. 244errors=panic Panic and halt the machine if an error occurs.
diff --git a/Documentation/filesystems/isofs.txt b/Documentation/filesystems/isofs.txt
index 6973b980ca2a..3c367c3b3608 100644
--- a/Documentation/filesystems/isofs.txt
+++ b/Documentation/filesystems/isofs.txt
@@ -23,8 +23,13 @@ Mount options unique to the isofs filesystem.
23 map=off Do not map non-Rock Ridge filenames to lower case 23 map=off Do not map non-Rock Ridge filenames to lower case
24 map=normal Map non-Rock Ridge filenames to lower case 24 map=normal Map non-Rock Ridge filenames to lower case
25 map=acorn As map=normal but also apply Acorn extensions if present 25 map=acorn As map=normal but also apply Acorn extensions if present
26 mode=xxx Sets the permissions on files to xxx 26 mode=xxx Sets the permissions on files to xxx unless Rock Ridge
27 dmode=xxx Sets the permissions on directories to xxx 27 extensions set the permissions otherwise
28 dmode=xxx Sets the permissions on directories to xxx unless Rock Ridge
29 extensions set the permissions otherwise
30 overriderockperm Set permissions on files and directories according to
31 'mode' and 'dmode' even though Rock Ridge extensions are
32 present.
28 nojoliet Ignore Joliet extensions if they are present. 33 nojoliet Ignore Joliet extensions if they are present.
29 norock Ignore Rock Ridge extensions if they are present. 34 norock Ignore Rock Ridge extensions if they are present.
30 hide Completely strip hidden files from the file system. 35 hide Completely strip hidden files from the file system.
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index ebff3c10a07f..fad18f9456e4 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -5,11 +5,12 @@
5 Bodo Bauer <bb@ricochet.net> 5 Bodo Bauer <bb@ricochet.net>
6 6
72.4.x update Jorge Nerin <comandante@zaralinux.com> November 14 2000 72.4.x update Jorge Nerin <comandante@zaralinux.com> November 14 2000
8move /proc/sys Shen Feng <shen@cn.fujitsu.com> April 1 2009 8move /proc/sys Shen Feng <shen@cn.fujitsu.com> April 1 2009
9------------------------------------------------------------------------------ 9------------------------------------------------------------------------------
10Version 1.3 Kernel version 2.2.12 10Version 1.3 Kernel version 2.2.12
11 Kernel version 2.4.0-test11-pre4 11 Kernel version 2.4.0-test11-pre4
12------------------------------------------------------------------------------ 12------------------------------------------------------------------------------
13fixes/update part 1.1 Stefani Seibold <stefani@seibold.net> June 9 2009
13 14
14Table of Contents 15Table of Contents
15----------------- 16-----------------
@@ -116,7 +117,7 @@ The link self points to the process reading the file system. Each process
116subdirectory has the entries listed in Table 1-1. 117subdirectory has the entries listed in Table 1-1.
117 118
118 119
119Table 1-1: Process specific entries in /proc 120Table 1-1: Process specific entries in /proc
120.............................................................................. 121..............................................................................
121 File Content 122 File Content
122 clear_refs Clears page referenced bits shown in smaps output 123 clear_refs Clears page referenced bits shown in smaps output
@@ -134,46 +135,103 @@ Table 1-1: Process specific entries in /proc
134 status Process status in human readable form 135 status Process status in human readable form
135 wchan If CONFIG_KALLSYMS is set, a pre-decoded wchan 136 wchan If CONFIG_KALLSYMS is set, a pre-decoded wchan
136 stack Report full stack trace, enable via CONFIG_STACKTRACE 137 stack Report full stack trace, enable via CONFIG_STACKTRACE
137 smaps Extension based on maps, the rss size for each mapped file 138 smaps a extension based on maps, showing the memory consumption of
139 each mapping
138.............................................................................. 140..............................................................................
139 141
140For example, to get the status information of a process, all you have to do is 142For example, to get the status information of a process, all you have to do is
141read the file /proc/PID/status: 143read the file /proc/PID/status:
142 144
143 >cat /proc/self/status 145 >cat /proc/self/status
144 Name: cat 146 Name: cat
145 State: R (running) 147 State: R (running)
146 Pid: 5452 148 Tgid: 5452
147 PPid: 743 149 Pid: 5452
150 PPid: 743
148 TracerPid: 0 (2.4) 151 TracerPid: 0 (2.4)
149 Uid: 501 501 501 501 152 Uid: 501 501 501 501
150 Gid: 100 100 100 100 153 Gid: 100 100 100 100
151 Groups: 100 14 16 154 FDSize: 256
152 VmSize: 1112 kB 155 Groups: 100 14 16
153 VmLck: 0 kB 156 VmPeak: 5004 kB
154 VmRSS: 348 kB 157 VmSize: 5004 kB
155 VmData: 24 kB 158 VmLck: 0 kB
156 VmStk: 12 kB 159 VmHWM: 476 kB
157 VmExe: 8 kB 160 VmRSS: 476 kB
158 VmLib: 1044 kB 161 VmData: 156 kB
159 SigPnd: 0000000000000000 162 VmStk: 88 kB
160 SigBlk: 0000000000000000 163 VmExe: 68 kB
161 SigIgn: 0000000000000000 164 VmLib: 1412 kB
162 SigCgt: 0000000000000000 165 VmPTE: 20 kb
163 CapInh: 00000000fffffeff 166 Threads: 1
164 CapPrm: 0000000000000000 167 SigQ: 0/28578
165 CapEff: 0000000000000000 168 SigPnd: 0000000000000000
166 169 ShdPnd: 0000000000000000
170 SigBlk: 0000000000000000
171 SigIgn: 0000000000000000
172 SigCgt: 0000000000000000
173 CapInh: 00000000fffffeff
174 CapPrm: 0000000000000000
175 CapEff: 0000000000000000
176 CapBnd: ffffffffffffffff
177 voluntary_ctxt_switches: 0
178 nonvoluntary_ctxt_switches: 1
167 179
168This shows you nearly the same information you would get if you viewed it with 180This shows you nearly the same information you would get if you viewed it with
169the ps command. In fact, ps uses the proc file system to obtain its 181the ps command. In fact, ps uses the proc file system to obtain its
170information. The statm file contains more detailed information about the 182information. But you get a more detailed view of the process by reading the
171process memory usage. Its seven fields are explained in Table 1-2. The stat 183file /proc/PID/status. It fields are described in table 1-2.
172file contains details information about the process itself. Its fields are 184
173explained in Table 1-3. 185The statm file contains more detailed information about the process
186memory usage. Its seven fields are explained in Table 1-3. The stat file
187contains details information about the process itself. Its fields are
188explained in Table 1-4.
174 189
190Table 1-2: Contents of the statm files (as of 2.6.30-rc7)
191..............................................................................
192 Field Content
193 Name filename of the executable
194 State state (R is running, S is sleeping, D is sleeping
195 in an uninterruptible wait, Z is zombie,
196 T is traced or stopped)
197 Tgid thread group ID
198 Pid process id
199 PPid process id of the parent process
200 TracerPid PID of process tracing this process (0 if not)
201 Uid Real, effective, saved set, and file system UIDs
202 Gid Real, effective, saved set, and file system GIDs
203 FDSize number of file descriptor slots currently allocated
204 Groups supplementary group list
205 VmPeak peak virtual memory size
206 VmSize total program size
207 VmLck locked memory size
208 VmHWM peak resident set size ("high water mark")
209 VmRSS size of memory portions
210 VmData size of data, stack, and text segments
211 VmStk size of data, stack, and text segments
212 VmExe size of text segment
213 VmLib size of shared library code
214 VmPTE size of page table entries
215 Threads number of threads
216 SigQ number of signals queued/max. number for queue
217 SigPnd bitmap of pending signals for the thread
218 ShdPnd bitmap of shared pending signals for the process
219 SigBlk bitmap of blocked signals
220 SigIgn bitmap of ignored signals
221 SigCgt bitmap of catched signals
222 CapInh bitmap of inheritable capabilities
223 CapPrm bitmap of permitted capabilities
224 CapEff bitmap of effective capabilities
225 CapBnd bitmap of capabilities bounding set
226 Cpus_allowed mask of CPUs on which this process may run
227 Cpus_allowed_list Same as previous, but in "list format"
228 Mems_allowed mask of memory nodes allowed to this process
229 Mems_allowed_list Same as previous, but in "list format"
230 voluntary_ctxt_switches number of voluntary context switches
231 nonvoluntary_ctxt_switches number of non voluntary context switches
232..............................................................................
175 233
176Table 1-2: Contents of the statm files (as of 2.6.8-rc3) 234Table 1-3: Contents of the statm files (as of 2.6.8-rc3)
177.............................................................................. 235..............................................................................
178 Field Content 236 Field Content
179 size total program size (pages) (same as VmSize in status) 237 size total program size (pages) (same as VmSize in status)
@@ -188,7 +246,7 @@ Table 1-2: Contents of the statm files (as of 2.6.8-rc3)
188.............................................................................. 246..............................................................................
189 247
190 248
191Table 1-3: Contents of the stat files (as of 2.6.22-rc3) 249Table 1-4: Contents of the stat files (as of 2.6.30-rc7)
192.............................................................................. 250..............................................................................
193 Field Content 251 Field Content
194 pid process id 252 pid process id
@@ -222,10 +280,10 @@ Table 1-3: Contents of the stat files (as of 2.6.22-rc3)
222 start_stack address of the start of the stack 280 start_stack address of the start of the stack
223 esp current value of ESP 281 esp current value of ESP
224 eip current value of EIP 282 eip current value of EIP
225 pending bitmap of pending signals (obsolete) 283 pending bitmap of pending signals
226 blocked bitmap of blocked signals (obsolete) 284 blocked bitmap of blocked signals
227 sigign bitmap of ignored signals (obsolete) 285 sigign bitmap of ignored signals
228 sigcatch bitmap of catched signals (obsolete) 286 sigcatch bitmap of catched signals
229 wchan address where process went to sleep 287 wchan address where process went to sleep
230 0 (place holder) 288 0 (place holder)
231 0 (place holder) 289 0 (place holder)
@@ -234,19 +292,99 @@ Table 1-3: Contents of the stat files (as of 2.6.22-rc3)
234 rt_priority realtime priority 292 rt_priority realtime priority
235 policy scheduling policy (man sched_setscheduler) 293 policy scheduling policy (man sched_setscheduler)
236 blkio_ticks time spent waiting for block IO 294 blkio_ticks time spent waiting for block IO
295 gtime guest time of the task in jiffies
296 cgtime guest time of the task children in jiffies
237.............................................................................. 297..............................................................................
238 298
299The /proc/PID/map file containing the currently mapped memory regions and
300their access permissions.
301
302The format is:
303
304address perms offset dev inode pathname
305
30608048000-08049000 r-xp 00000000 03:00 8312 /opt/test
30708049000-0804a000 rw-p 00001000 03:00 8312 /opt/test
3080804a000-0806b000 rw-p 00000000 00:00 0 [heap]
309a7cb1000-a7cb2000 ---p 00000000 00:00 0
310a7cb2000-a7eb2000 rw-p 00000000 00:00 0
311a7eb2000-a7eb3000 ---p 00000000 00:00 0
312a7eb3000-a7ed5000 rw-p 00000000 00:00 0
313a7ed5000-a8008000 r-xp 00000000 03:00 4222 /lib/libc.so.6
314a8008000-a800a000 r--p 00133000 03:00 4222 /lib/libc.so.6
315a800a000-a800b000 rw-p 00135000 03:00 4222 /lib/libc.so.6
316a800b000-a800e000 rw-p 00000000 00:00 0
317a800e000-a8022000 r-xp 00000000 03:00 14462 /lib/libpthread.so.0
318a8022000-a8023000 r--p 00013000 03:00 14462 /lib/libpthread.so.0
319a8023000-a8024000 rw-p 00014000 03:00 14462 /lib/libpthread.so.0
320a8024000-a8027000 rw-p 00000000 00:00 0
321a8027000-a8043000 r-xp 00000000 03:00 8317 /lib/ld-linux.so.2
322a8043000-a8044000 r--p 0001b000 03:00 8317 /lib/ld-linux.so.2
323a8044000-a8045000 rw-p 0001c000 03:00 8317 /lib/ld-linux.so.2
324aff35000-aff4a000 rw-p 00000000 00:00 0 [stack]
325ffffe000-fffff000 r-xp 00000000 00:00 0 [vdso]
326
327where "address" is the address space in the process that it occupies, "perms"
328is a set of permissions:
329
330 r = read
331 w = write
332 x = execute
333 s = shared
334 p = private (copy on write)
335
336"offset" is the offset into the mapping, "dev" is the device (major:minor), and
337"inode" is the inode on that device. 0 indicates that no inode is associated
338with the memory region, as the case would be with BSS (uninitialized data).
339The "pathname" shows the name associated file for this mapping. If the mapping
340is not associated with a file:
341
342 [heap] = the heap of the program
343 [stack] = the stack of the main process
344 [vdso] = the "virtual dynamic shared object",
345 the kernel system call handler
346
347 or if empty, the mapping is anonymous.
348
349
350The /proc/PID/smaps is an extension based on maps, showing the memory
351consumption for each of the process's mappings. For each of mappings there
352is a series of lines such as the following:
353
35408048000-080bc000 r-xp 00000000 03:02 13130 /bin/bash
355Size: 1084 kB
356Rss: 892 kB
357Pss: 374 kB
358Shared_Clean: 892 kB
359Shared_Dirty: 0 kB
360Private_Clean: 0 kB
361Private_Dirty: 0 kB
362Referenced: 892 kB
363Swap: 0 kB
364KernelPageSize: 4 kB
365MMUPageSize: 4 kB
366
367The first of these lines shows the same information as is displayed for the
368mapping in /proc/PID/maps. The remaining lines show the size of the mapping,
369the amount of the mapping that is currently resident in RAM, the "proportional
370set size” (divide each shared page by the number of processes sharing it), the
371number of clean and dirty shared pages in the mapping, and the number of clean
372and dirty private pages in the mapping. The "Referenced" indicates the amount
373of memory currently marked as referenced or accessed.
374
375This file is only present if the CONFIG_MMU kernel configuration option is
376enabled.
239 377
2401.2 Kernel data 3781.2 Kernel data
241--------------- 379---------------
242 380
243Similar to the process entries, the kernel data files give information about 381Similar to the process entries, the kernel data files give information about
244the running kernel. The files used to obtain this information are contained in 382the running kernel. The files used to obtain this information are contained in
245/proc and are listed in Table 1-4. Not all of these will be present in your 383/proc and are listed in Table 1-5. Not all of these will be present in your
246system. It depends on the kernel configuration and the loaded modules, which 384system. It depends on the kernel configuration and the loaded modules, which
247files are there, and which are missing. 385files are there, and which are missing.
248 386
249Table 1-4: Kernel info in /proc 387Table 1-5: Kernel info in /proc
250.............................................................................. 388..............................................................................
251 File Content 389 File Content
252 apm Advanced power management info 390 apm Advanced power management info
@@ -283,6 +421,7 @@ Table 1-4: Kernel info in /proc
283 rtc Real time clock 421 rtc Real time clock
284 scsi SCSI info (see text) 422 scsi SCSI info (see text)
285 slabinfo Slab pool info 423 slabinfo Slab pool info
424 softirqs softirq usage
286 stat Overall statistics 425 stat Overall statistics
287 swaps Swap space utilization 426 swaps Swap space utilization
288 sys See chapter 2 427 sys See chapter 2
@@ -597,6 +736,25 @@ on the kind of area :
5970xffffffffa0017000-0xffffffffa0022000 45056 sys_init_module+0xc27/0x1d00 ... 7360xffffffffa0017000-0xffffffffa0022000 45056 sys_init_module+0xc27/0x1d00 ...
598 pages=10 vmalloc N0=10 737 pages=10 vmalloc N0=10
599 738
739..............................................................................
740
741softirqs:
742
743Provides counts of softirq handlers serviced since boot time, for each cpu.
744
745> cat /proc/softirqs
746 CPU0 CPU1 CPU2 CPU3
747 HI: 0 0 0 0
748 TIMER: 27166 27120 27097 27034
749 NET_TX: 0 0 0 17
750 NET_RX: 42 0 0 39
751 BLOCK: 0 0 107 1121
752 TASKLET: 0 0 0 290
753 SCHED: 27035 26983 26971 26746
754 HRTIMER: 0 0 0 0
755 RCU: 1678 1769 2178 2250
756
757
6001.3 IDE devices in /proc/ide 7581.3 IDE devices in /proc/ide
601---------------------------- 759----------------------------
602 760
@@ -614,10 +772,10 @@ IDE devices:
614 772
615More detailed information can be found in the controller specific 773More detailed information can be found in the controller specific
616subdirectories. These are named ide0, ide1 and so on. Each of these 774subdirectories. These are named ide0, ide1 and so on. Each of these
617directories contains the files shown in table 1-5. 775directories contains the files shown in table 1-6.
618 776
619 777
620Table 1-5: IDE controller info in /proc/ide/ide? 778Table 1-6: IDE controller info in /proc/ide/ide?
621.............................................................................. 779..............................................................................
622 File Content 780 File Content
623 channel IDE channel (0 or 1) 781 channel IDE channel (0 or 1)
@@ -627,11 +785,11 @@ Table 1-5: IDE controller info in /proc/ide/ide?
627.............................................................................. 785..............................................................................
628 786
629Each device connected to a controller has a separate subdirectory in the 787Each device connected to a controller has a separate subdirectory in the
630controllers directory. The files listed in table 1-6 are contained in these 788controllers directory. The files listed in table 1-7 are contained in these
631directories. 789directories.
632 790
633 791
634Table 1-6: IDE device information 792Table 1-7: IDE device information
635.............................................................................. 793..............................................................................
636 File Content 794 File Content
637 cache The cache 795 cache The cache
@@ -673,12 +831,12 @@ the drive parameters:
6731.4 Networking info in /proc/net 8311.4 Networking info in /proc/net
674-------------------------------- 832--------------------------------
675 833
676The subdirectory /proc/net follows the usual pattern. Table 1-6 shows the 834The subdirectory /proc/net follows the usual pattern. Table 1-8 shows the
677additional values you get for IP version 6 if you configure the kernel to 835additional values you get for IP version 6 if you configure the kernel to
678support this. Table 1-7 lists the files and their meaning. 836support this. Table 1-9 lists the files and their meaning.
679 837
680 838
681Table 1-6: IPv6 info in /proc/net 839Table 1-8: IPv6 info in /proc/net
682.............................................................................. 840..............................................................................
683 File Content 841 File Content
684 udp6 UDP sockets (IPv6) 842 udp6 UDP sockets (IPv6)
@@ -693,7 +851,7 @@ Table 1-6: IPv6 info in /proc/net
693.............................................................................. 851..............................................................................
694 852
695 853
696Table 1-7: Network info in /proc/net 854Table 1-9: Network info in /proc/net
697.............................................................................. 855..............................................................................
698 File Content 856 File Content
699 arp Kernel ARP table 857 arp Kernel ARP table
@@ -817,10 +975,10 @@ The directory /proc/parport contains information about the parallel ports of
817your system. It has one subdirectory for each port, named after the port 975your system. It has one subdirectory for each port, named after the port
818number (0,1,2,...). 976number (0,1,2,...).
819 977
820These directories contain the four files shown in Table 1-8. 978These directories contain the four files shown in Table 1-10.
821 979
822 980
823Table 1-8: Files in /proc/parport 981Table 1-10: Files in /proc/parport
824.............................................................................. 982..............................................................................
825 File Content 983 File Content
826 autoprobe Any IEEE-1284 device ID information that has been acquired. 984 autoprobe Any IEEE-1284 device ID information that has been acquired.
@@ -838,10 +996,10 @@ Table 1-8: Files in /proc/parport
838 996
839Information about the available and actually used tty's can be found in the 997Information about the available and actually used tty's can be found in the
840directory /proc/tty.You'll find entries for drivers and line disciplines in 998directory /proc/tty.You'll find entries for drivers and line disciplines in
841this directory, as shown in Table 1-9. 999this directory, as shown in Table 1-11.
842 1000
843 1001
844Table 1-9: Files in /proc/tty 1002Table 1-11: Files in /proc/tty
845.............................................................................. 1003..............................................................................
846 File Content 1004 File Content
847 drivers list of drivers and their usage 1005 drivers list of drivers and their usage
@@ -883,6 +1041,7 @@ since the system first booted. For a quick look, simply cat the file:
883 processes 2915 1041 processes 2915
884 procs_running 1 1042 procs_running 1
885 procs_blocked 0 1043 procs_blocked 0
1044 softirq 183433 0 21755 12 39 1137 231 21459 2263
886 1045
887The very first "cpu" line aggregates the numbers in all of the other "cpuN" 1046The very first "cpu" line aggregates the numbers in all of the other "cpuN"
888lines. These numbers identify the amount of time the CPU has spent performing 1047lines. These numbers identify the amount of time the CPU has spent performing
@@ -918,6 +1077,11 @@ CPUs.
918The "procs_blocked" line gives the number of processes currently blocked, 1077The "procs_blocked" line gives the number of processes currently blocked,
919waiting for I/O to complete. 1078waiting for I/O to complete.
920 1079
1080The "softirq" line gives counts of softirqs serviced since boot time, for each
1081of the possible system softirqs. The first column is the total of all
1082softirqs serviced; each subsequent column is the total for that particular
1083softirq.
1084
921 1085
9221.9 Ext4 file system parameters 10861.9 Ext4 file system parameters
923------------------------------ 1087------------------------------
@@ -926,9 +1090,9 @@ Information about mounted ext4 file systems can be found in
926/proc/fs/ext4. Each mounted filesystem will have a directory in 1090/proc/fs/ext4. Each mounted filesystem will have a directory in
927/proc/fs/ext4 based on its device name (i.e., /proc/fs/ext4/hdc or 1091/proc/fs/ext4 based on its device name (i.e., /proc/fs/ext4/hdc or
928/proc/fs/ext4/dm-0). The files in each per-device directory are shown 1092/proc/fs/ext4/dm-0). The files in each per-device directory are shown
929in Table 1-10, below. 1093in Table 1-12, below.
930 1094
931Table 1-10: Files in /proc/fs/ext4/<devname> 1095Table 1-12: Files in /proc/fs/ext4/<devname>
932.............................................................................. 1096..............................................................................
933 File Content 1097 File Content
934 mb_groups details of multiblock allocator buddy cache of free blocks 1098 mb_groups details of multiblock allocator buddy cache of free blocks
diff --git a/Documentation/gcov.txt b/Documentation/gcov.txt
new file mode 100644
index 000000000000..e716aadb3a33
--- /dev/null
+++ b/Documentation/gcov.txt
@@ -0,0 +1,246 @@
1Using gcov with the Linux kernel
2================================
3
41. Introduction
52. Preparation
63. Customization
74. Files
85. Modules
96. Separated build and test machines
107. Troubleshooting
11Appendix A: sample script: gather_on_build.sh
12Appendix B: sample script: gather_on_test.sh
13
14
151. Introduction
16===============
17
18gcov profiling kernel support enables the use of GCC's coverage testing
19tool gcov [1] with the Linux kernel. Coverage data of a running kernel
20is exported in gcov-compatible format via the "gcov" debugfs directory.
21To get coverage data for a specific file, change to the kernel build
22directory and use gcov with the -o option as follows (requires root):
23
24# cd /tmp/linux-out
25# gcov -o /sys/kernel/debug/gcov/tmp/linux-out/kernel spinlock.c
26
27This will create source code files annotated with execution counts
28in the current directory. In addition, graphical gcov front-ends such
29as lcov [2] can be used to automate the process of collecting data
30for the entire kernel and provide coverage overviews in HTML format.
31
32Possible uses:
33
34* debugging (has this line been reached at all?)
35* test improvement (how do I change my test to cover these lines?)
36* minimizing kernel configurations (do I need this option if the
37 associated code is never run?)
38
39--
40
41[1] http://gcc.gnu.org/onlinedocs/gcc/Gcov.html
42[2] http://ltp.sourceforge.net/coverage/lcov.php
43
44
452. Preparation
46==============
47
48Configure the kernel with:
49
50 CONFIG_DEBUGFS=y
51 CONFIG_GCOV_KERNEL=y
52
53and to get coverage data for the entire kernel:
54
55 CONFIG_GCOV_PROFILE_ALL=y
56
57Note that kernels compiled with profiling flags will be significantly
58larger and run slower. Also CONFIG_GCOV_PROFILE_ALL may not be supported
59on all architectures.
60
61Profiling data will only become accessible once debugfs has been
62mounted:
63
64 mount -t debugfs none /sys/kernel/debug
65
66
673. Customization
68================
69
70To enable profiling for specific files or directories, add a line
71similar to the following to the respective kernel Makefile:
72
73 For a single file (e.g. main.o):
74 GCOV_PROFILE_main.o := y
75
76 For all files in one directory:
77 GCOV_PROFILE := y
78
79To exclude files from being profiled even when CONFIG_GCOV_PROFILE_ALL
80is specified, use:
81
82 GCOV_PROFILE_main.o := n
83 and:
84 GCOV_PROFILE := n
85
86Only files which are linked to the main kernel image or are compiled as
87kernel modules are supported by this mechanism.
88
89
904. Files
91========
92
93The gcov kernel support creates the following files in debugfs:
94
95 /sys/kernel/debug/gcov
96 Parent directory for all gcov-related files.
97
98 /sys/kernel/debug/gcov/reset
99 Global reset file: resets all coverage data to zero when
100 written to.
101
102 /sys/kernel/debug/gcov/path/to/compile/dir/file.gcda
103 The actual gcov data file as understood by the gcov
104 tool. Resets file coverage data to zero when written to.
105
106 /sys/kernel/debug/gcov/path/to/compile/dir/file.gcno
107 Symbolic link to a static data file required by the gcov
108 tool. This file is generated by gcc when compiling with
109 option -ftest-coverage.
110
111
1125. Modules
113==========
114
115Kernel modules may contain cleanup code which is only run during
116module unload time. The gcov mechanism provides a means to collect
117coverage data for such code by keeping a copy of the data associated
118with the unloaded module. This data remains available through debugfs.
119Once the module is loaded again, the associated coverage counters are
120initialized with the data from its previous instantiation.
121
122This behavior can be deactivated by specifying the gcov_persist kernel
123parameter:
124
125 gcov_persist=0
126
127At run-time, a user can also choose to discard data for an unloaded
128module by writing to its data file or the global reset file.
129
130
1316. Separated build and test machines
132====================================
133
134The gcov kernel profiling infrastructure is designed to work out-of-the
135box for setups where kernels are built and run on the same machine. In
136cases where the kernel runs on a separate machine, special preparations
137must be made, depending on where the gcov tool is used:
138
139a) gcov is run on the TEST machine
140
141The gcov tool version on the test machine must be compatible with the
142gcc version used for kernel build. Also the following files need to be
143copied from build to test machine:
144
145from the source tree:
146 - all C source files + headers
147
148from the build tree:
149 - all C source files + headers
150 - all .gcda and .gcno files
151 - all links to directories
152
153It is important to note that these files need to be placed into the
154exact same file system location on the test machine as on the build
155machine. If any of the path components is symbolic link, the actual
156directory needs to be used instead (due to make's CURDIR handling).
157
158b) gcov is run on the BUILD machine
159
160The following files need to be copied after each test case from test
161to build machine:
162
163from the gcov directory in sysfs:
164 - all .gcda files
165 - all links to .gcno files
166
167These files can be copied to any location on the build machine. gcov
168must then be called with the -o option pointing to that directory.
169
170Example directory setup on the build machine:
171
172 /tmp/linux: kernel source tree
173 /tmp/out: kernel build directory as specified by make O=
174 /tmp/coverage: location of the files copied from the test machine
175
176 [user@build] cd /tmp/out
177 [user@build] gcov -o /tmp/coverage/tmp/out/init main.c
178
179
1807. Troubleshooting
181==================
182
183Problem: Compilation aborts during linker step.
184Cause: Profiling flags are specified for source files which are not
185 linked to the main kernel or which are linked by a custom
186 linker procedure.
187Solution: Exclude affected source files from profiling by specifying
188 GCOV_PROFILE := n or GCOV_PROFILE_basename.o := n in the
189 corresponding Makefile.
190
191
192Appendix A: gather_on_build.sh
193==============================
194
195Sample script to gather coverage meta files on the build machine
196(see 6a):
197
198#!/bin/bash
199
200KSRC=$1
201KOBJ=$2
202DEST=$3
203
204if [ -z "$KSRC" ] || [ -z "$KOBJ" ] || [ -z "$DEST" ]; then
205 echo "Usage: $0 <ksrc directory> <kobj directory> <output.tar.gz>" >&2
206 exit 1
207fi
208
209KSRC=$(cd $KSRC; printf "all:\n\t@echo \${CURDIR}\n" | make -f -)
210KOBJ=$(cd $KOBJ; printf "all:\n\t@echo \${CURDIR}\n" | make -f -)
211
212find $KSRC $KOBJ \( -name '*.gcno' -o -name '*.[ch]' -o -type l \) -a \
213 -perm /u+r,g+r | tar cfz $DEST -P -T -
214
215if [ $? -eq 0 ] ; then
216 echo "$DEST successfully created, copy to test system and unpack with:"
217 echo " tar xfz $DEST -P"
218else
219 echo "Could not create file $DEST"
220fi
221
222
223Appendix B: gather_on_test.sh
224=============================
225
226Sample script to gather coverage data files on the test machine
227(see 6b):
228
229#!/bin/bash
230
231DEST=$1
232GCDA=/sys/kernel/debug/gcov
233
234if [ -z "$DEST" ] ; then
235 echo "Usage: $0 <output.tar.gz>" >&2
236 exit 1
237fi
238
239find $GCDA -name '*.gcno' -o -name '*.gcda' | tar cfz $DEST -T -
240
241if [ $? -eq 0 ] ; then
242 echo "$DEST successfully created, copy to build system and unpack with:"
243 echo " tar xfz $DEST"
244else
245 echo "Could not create file $DEST"
246fi
diff --git a/Documentation/ioctl/ioctl-number.txt b/Documentation/ioctl/ioctl-number.txt
index 1f779a25c703..7bb0d934b6d8 100644
--- a/Documentation/ioctl/ioctl-number.txt
+++ b/Documentation/ioctl/ioctl-number.txt
@@ -149,6 +149,8 @@ Code Seq# Include File Comments
149'p' 40-7F linux/nvram.h 149'p' 40-7F linux/nvram.h
150'p' 80-9F user-space parport 150'p' 80-9F user-space parport
151 <mailto:tim@cyberelk.net> 151 <mailto:tim@cyberelk.net>
152'p' a1-a4 linux/pps.h LinuxPPS
153 <mailto:giometti@linux.it>
152'q' 00-1F linux/serio.h 154'q' 00-1F linux/serio.h
153'q' 80-FF Internet PhoneJACK, Internet LineJACK 155'q' 80-FF Internet PhoneJACK, Internet LineJACK
154 <http://www.quicknet.net> 156 <http://www.quicknet.net>
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 5578248c18a4..08def8deb5f5 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -48,6 +48,7 @@ parameter is applicable:
48 EFI EFI Partitioning (GPT) is enabled 48 EFI EFI Partitioning (GPT) is enabled
49 EIDE EIDE/ATAPI support is enabled. 49 EIDE EIDE/ATAPI support is enabled.
50 FB The frame buffer device is enabled. 50 FB The frame buffer device is enabled.
51 GCOV GCOV profiling is enabled.
51 HW Appropriate hardware is enabled. 52 HW Appropriate hardware is enabled.
52 IA-64 IA-64 architecture is enabled. 53 IA-64 IA-64 architecture is enabled.
53 IMA Integrity measurement architecture is enabled. 54 IMA Integrity measurement architecture is enabled.
@@ -796,6 +797,12 @@ and is between 256 and 4096 characters. It is defined in the file
796 Format: off | on 797 Format: off | on
797 default: on 798 default: on
798 799
800 gcov_persist= [GCOV] When non-zero (default), profiling data for
801 kernel modules is saved and remains accessible via
802 debugfs, even when the module is unloaded/reloaded.
803 When zero, profiling data is discarded and associated
804 debugfs files are removed at module unload time.
805
799 gdth= [HW,SCSI] 806 gdth= [HW,SCSI]
800 See header of drivers/scsi/gdth.c. 807 See header of drivers/scsi/gdth.c.
801 808
diff --git a/Documentation/pps/pps.txt b/Documentation/pps/pps.txt
new file mode 100644
index 000000000000..125f4ab48998
--- /dev/null
+++ b/Documentation/pps/pps.txt
@@ -0,0 +1,172 @@
1
2 PPS - Pulse Per Second
3 ----------------------
4
5(C) Copyright 2007 Rodolfo Giometti <giometti@enneenne.com>
6
7This program is free software; you can redistribute it and/or modify
8it under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 2 of the License, or
10(at your option) any later version.
11
12This program is distributed in the hope that it will be useful,
13but WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15GNU General Public License for more details.
16
17
18
19Overview
20--------
21
22LinuxPPS provides a programming interface (API) to define in the
23system several PPS sources.
24
25PPS means "pulse per second" and a PPS source is just a device which
26provides a high precision signal each second so that an application
27can use it to adjust system clock time.
28
29A PPS source can be connected to a serial port (usually to the Data
30Carrier Detect pin) or to a parallel port (ACK-pin) or to a special
31CPU's GPIOs (this is the common case in embedded systems) but in each
32case when a new pulse arrives the system must apply to it a timestamp
33and record it for userland.
34
35Common use is the combination of the NTPD as userland program, with a
36GPS receiver as PPS source, to obtain a wallclock-time with
37sub-millisecond synchronisation to UTC.
38
39
40RFC considerations
41------------------
42
43While implementing a PPS API as RFC 2783 defines and using an embedded
44CPU GPIO-Pin as physical link to the signal, I encountered a deeper
45problem:
46
47 At startup it needs a file descriptor as argument for the function
48 time_pps_create().
49
50This implies that the source has a /dev/... entry. This assumption is
51ok for the serial and parallel port, where you can do something
52useful besides(!) the gathering of timestamps as it is the central
53task for a PPS-API. But this assumption does not work for a single
54purpose GPIO line. In this case even basic file-related functionality
55(like read() and write()) makes no sense at all and should not be a
56precondition for the use of a PPS-API.
57
58The problem can be simply solved if you consider that a PPS source is
59not always connected with a GPS data source.
60
61So your programs should check if the GPS data source (the serial port
62for instance) is a PPS source too, and if not they should provide the
63possibility to open another device as PPS source.
64
65In LinuxPPS the PPS sources are simply char devices usually mapped
66into files /dev/pps0, /dev/pps1, etc..
67
68
69Coding example
70--------------
71
72To register a PPS source into the kernel you should define a struct
73pps_source_info_s as follows:
74
75 static struct pps_source_info pps_ktimer_info = {
76 .name = "ktimer",
77 .path = "",
78 .mode = PPS_CAPTUREASSERT | PPS_OFFSETASSERT | \
79 PPS_ECHOASSERT | \
80 PPS_CANWAIT | PPS_TSFMT_TSPEC,
81 .echo = pps_ktimer_echo,
82 .owner = THIS_MODULE,
83 };
84
85and then calling the function pps_register_source() in your
86intialization routine as follows:
87
88 source = pps_register_source(&pps_ktimer_info,
89 PPS_CAPTUREASSERT | PPS_OFFSETASSERT);
90
91The pps_register_source() prototype is:
92
93 int pps_register_source(struct pps_source_info_s *info, int default_params)
94
95where "info" is a pointer to a structure that describes a particular
96PPS source, "default_params" tells the system what the initial default
97parameters for the device should be (it is obvious that these parameters
98must be a subset of ones defined in the struct
99pps_source_info_s which describe the capabilities of the driver).
100
101Once you have registered a new PPS source into the system you can
102signal an assert event (for example in the interrupt handler routine)
103just using:
104
105 pps_event(source, &ts, PPS_CAPTUREASSERT, ptr)
106
107where "ts" is the event's timestamp.
108
109The same function may also run the defined echo function
110(pps_ktimer_echo(), passing to it the "ptr" pointer) if the user
111asked for that... etc..
112
113Please see the file drivers/pps/clients/ktimer.c for example code.
114
115
116SYSFS support
117-------------
118
119If the SYSFS filesystem is enabled in the kernel it provides a new class:
120
121 $ ls /sys/class/pps/
122 pps0/ pps1/ pps2/
123
124Every directory is the ID of a PPS sources defined in the system and
125inside you find several files:
126
127 $ ls /sys/class/pps/pps0/
128 assert clear echo mode name path subsystem@ uevent
129
130Inside each "assert" and "clear" file you can find the timestamp and a
131sequence number:
132
133 $ cat /sys/class/pps/pps0/assert
134 1170026870.983207967#8
135
136Where before the "#" is the timestamp in seconds; after it is the
137sequence number. Other files are:
138
139* echo: reports if the PPS source has an echo function or not;
140
141* mode: reports available PPS functioning modes;
142
143* name: reports the PPS source's name;
144
145* path: reports the PPS source's device path, that is the device the
146 PPS source is connected to (if it exists).
147
148
149Testing the PPS support
150-----------------------
151
152In order to test the PPS support even without specific hardware you can use
153the ktimer driver (see the client subsection in the PPS configuration menu)
154and the userland tools provided into Documentaion/pps/ directory.
155
156Once you have enabled the compilation of ktimer just modprobe it (if
157not statically compiled):
158
159 # modprobe ktimer
160
161and the run ppstest as follow:
162
163 $ ./ppstest /dev/pps0
164 trying PPS source "/dev/pps1"
165 found PPS source "/dev/pps1"
166 ok, found 1 source(s), now start fetching data...
167 source 0 - assert 1186592699.388832443, sequence: 364 - clear 0.000000000, sequence: 0
168 source 0 - assert 1186592700.388931295, sequence: 365 - clear 0.000000000, sequence: 0
169 source 0 - assert 1186592701.389032765, sequence: 366 - clear 0.000000000, sequence: 0
170
171Please, note that to compile userland programs you need the file timepps.h
172(see Documentation/pps/).
diff --git a/Documentation/rfkill.txt b/Documentation/rfkill.txt
index 1b74b5f30af4..c8acd8659e91 100644
--- a/Documentation/rfkill.txt
+++ b/Documentation/rfkill.txt
@@ -3,9 +3,8 @@ rfkill - RF kill switch support
3 3
41. Introduction 41. Introduction
52. Implementation details 52. Implementation details
63. Kernel driver guidelines 63. Kernel API
74. Kernel API 74. Userspace support
85. Userspace support
9 8
10 9
111. Introduction 101. Introduction
@@ -19,82 +18,62 @@ disable all transmitters of a certain type (or all). This is intended for
19situations where transmitters need to be turned off, for example on 18situations where transmitters need to be turned off, for example on
20aircraft. 19aircraft.
21 20
21The rfkill subsystem has a concept of "hard" and "soft" block, which
22differ little in their meaning (block == transmitters off) but rather in
23whether they can be changed or not:
24 - hard block: read-only radio block that cannot be overriden by software
25 - soft block: writable radio block (need not be readable) that is set by
26 the system software.
22 27
23 28
242. Implementation details 292. Implementation details
25 30
26The rfkill subsystem is composed of various components: the rfkill class, the 31The rfkill subsystem is composed of three main components:
27rfkill-input module (an input layer handler), and some specific input layer 32 * the rfkill core,
28events. 33 * the deprecated rfkill-input module (an input layer handler, being
29 34 replaced by userspace policy code) and
30The rfkill class is provided for kernel drivers to register their radio 35 * the rfkill drivers.
31transmitter with the kernel, provide methods for turning it on and off and,
32optionally, letting the system know about hardware-disabled states that may
33be implemented on the device. This code is enabled with the CONFIG_RFKILL
34Kconfig option, which drivers can "select".
35
36The rfkill class code also notifies userspace of state changes, this is
37achieved via uevents. It also provides some sysfs files for userspace to
38check the status of radio transmitters. See the "Userspace support" section
39below.
40 36
37The rfkill core provides API for kernel drivers to register their radio
38transmitter with the kernel, methods for turning it on and off and, letting
39the system know about hardware-disabled states that may be implemented on
40the device.
41 41
42The rfkill-input code implements a basic response to rfkill buttons -- it 42The rfkill core code also notifies userspace of state changes, and provides
43implements turning on/off all devices of a certain class (or all). 43ways for userspace to query the current states. See the "Userspace support"
44section below.
44 45
45When the device is hard-blocked (either by a call to rfkill_set_hw_state() 46When the device is hard-blocked (either by a call to rfkill_set_hw_state()
46or from query_hw_block) set_block() will be invoked but drivers can well 47or from query_hw_block) set_block() will be invoked for additional software
47ignore the method call since they can use the return value of the function 48block, but drivers can ignore the method call since they can use the return
48rfkill_set_hw_state() to sync the software state instead of keeping track 49value of the function rfkill_set_hw_state() to sync the software state
49of calls to set_block(). 50instead of keeping track of calls to set_block(). In fact, drivers should
50 51use the return value of rfkill_set_hw_state() unless the hardware actually
51 52keeps track of soft and hard block separately.
52The entire functionality is spread over more than one subsystem:
53
54 * The kernel input layer generates KEY_WWAN, KEY_WLAN etc. and
55 SW_RFKILL_ALL -- when the user presses a button. Drivers for radio
56 transmitters generally do not register to the input layer, unless the
57 device really provides an input device (i.e. a button that has no
58 effect other than generating a button press event)
59
60 * The rfkill-input code hooks up to these events and switches the soft-block
61 of the various radio transmitters, depending on the button type.
62
63 * The rfkill drivers turn off/on their transmitters as requested.
64
65 * The rfkill class will generate userspace notifications (uevents) to tell
66 userspace what the current state is.
67 53
68 54
553. Kernel API
69 56
703. Kernel driver guidelines
71 57
72 58Drivers for radio transmitters normally implement an rfkill driver.
73Drivers for radio transmitters normally implement only the rfkill class.
74These drivers may not unblock the transmitter based on own decisions, they
75should act on information provided by the rfkill class only.
76 59
77Platform drivers might implement input devices if the rfkill button is just 60Platform drivers might implement input devices if the rfkill button is just
78that, a button. If that button influences the hardware then you need to 61that, a button. If that button influences the hardware then you need to
79implement an rfkill class instead. This also applies if the platform provides 62implement an rfkill driver instead. This also applies if the platform provides
80a way to turn on/off the transmitter(s). 63a way to turn on/off the transmitter(s).
81 64
82During suspend/hibernation, transmitters should only be left enabled when 65For some platforms, it is possible that the hardware state changes during
83wake-on wlan or similar functionality requires it and the device wasn't 66suspend/hibernation, in which case it will be necessary to update the rfkill
84blocked before suspend/hibernate. Note that it may be necessary to update 67core with the current state is at resume time.
85the rfkill subsystem's idea of what the current state is at resume time if
86the state may have changed over suspend.
87
88 68
69To create an rfkill driver, driver's Kconfig needs to have
89 70
904. Kernel API 71 depends on RFKILL || !RFKILL
91 72
92To build a driver with rfkill subsystem support, the driver should depend on 73to ensure the driver cannot be built-in when rfkill is modular. The !RFKILL
93(or select) the Kconfig symbol RFKILL. 74case allows the driver to be built when rfkill is not configured, which which
94 75case all rfkill API can still be used but will be provided by static inlines
95The hardware the driver talks to may be write-only (where the current state 76which compile to almost nothing.
96of the hardware is unknown), or read-write (where the hardware can be queried
97about its current state).
98 77
99Calling rfkill_set_hw_state() when a state change happens is required from 78Calling rfkill_set_hw_state() when a state change happens is required from
100rfkill drivers that control devices that can be hard-blocked unless they also 79rfkill drivers that control devices that can be hard-blocked unless they also
@@ -105,10 +84,33 @@ device). Don't do this unless you cannot get the event in any other way.
105 84
1065. Userspace support 855. Userspace support
107 86
108The following sysfs entries exist for every rfkill device: 87The recommended userspace interface to use is /dev/rfkill, which is a misc
88character device that allows userspace to obtain and set the state of rfkill
89devices and sets of devices. It also notifies userspace about device addition
90and removal. The API is a simple read/write API that is defined in
91linux/rfkill.h, with one ioctl that allows turning off the deprecated input
92handler in the kernel for the transition period.
93
94Except for the one ioctl, communication with the kernel is done via read()
95and write() of instances of 'struct rfkill_event'. In this structure, the
96soft and hard block are properly separated (unlike sysfs, see below) and
97userspace is able to get a consistent snapshot of all rfkill devices in the
98system. Also, it is possible to switch all rfkill drivers (or all drivers of
99a specified type) into a state which also updates the default state for
100hotplugged devices.
101
102After an application opens /dev/rfkill, it can read the current state of
103all devices, and afterwards can poll the descriptor for hotplug or state
104change events.
105
106Applications must ignore operations (the "op" field) they do not handle,
107this allows the API to be extended in the future.
108
109Additionally, each rfkill device is registered in sysfs and there has the
110following attributes:
109 111
110 name: Name assigned by driver to this key (interface or driver name). 112 name: Name assigned by driver to this key (interface or driver name).
111 type: Name of the key type ("wlan", "bluetooth", etc). 113 type: Driver type string ("wlan", "bluetooth", etc).
112 state: Current state of the transmitter 114 state: Current state of the transmitter
113 0: RFKILL_STATE_SOFT_BLOCKED 115 0: RFKILL_STATE_SOFT_BLOCKED
114 transmitter is turned off by software 116 transmitter is turned off by software
@@ -117,7 +119,12 @@ The following sysfs entries exist for every rfkill device:
117 2: RFKILL_STATE_HARD_BLOCKED 119 2: RFKILL_STATE_HARD_BLOCKED
118 transmitter is forced off by something outside of 120 transmitter is forced off by something outside of
119 the driver's control. 121 the driver's control.
120 claim: 0: Kernel handles events (currently always reads that value) 122 This file is deprecated because it can only properly show
123 three of the four possible states, soft-and-hard-blocked is
124 missing.
125 claim: 0: Kernel handles events
126 This file is deprecated because there no longer is a way to
127 claim just control over a single rfkill instance.
121 128
122rfkill devices also issue uevents (with an action of "change"), with the 129rfkill devices also issue uevents (with an action of "change"), with the
123following environment variables set: 130following environment variables set:
@@ -128,9 +135,3 @@ RFKILL_TYPE
128 135
129The contents of these variables corresponds to the "name", "state" and 136The contents of these variables corresponds to the "name", "state" and
130"type" sysfs files explained above. 137"type" sysfs files explained above.
131
132An alternative userspace interface exists as a misc device /dev/rfkill,
133which allows userspace to obtain and set the state of rfkill devices and
134sets of devices. It also notifies userspace about device addition and
135removal. The API is a simple read/write API that is defined in
136linux/rfkill.h.
diff --git a/Documentation/robust-futex-ABI.txt b/Documentation/robust-futex-ABI.txt
index 535f69fab45f..fd1cd8aae4eb 100644
--- a/Documentation/robust-futex-ABI.txt
+++ b/Documentation/robust-futex-ABI.txt
@@ -135,7 +135,7 @@ manipulating this list), the user code must observe the following
135protocol on 'lock entry' insertion and removal: 135protocol on 'lock entry' insertion and removal:
136 136
137On insertion: 137On insertion:
138 1) set the 'list_op_pending' word to the address of the 'lock word' 138 1) set the 'list_op_pending' word to the address of the 'lock entry'
139 to be inserted, 139 to be inserted,
140 2) acquire the futex lock, 140 2) acquire the futex lock,
141 3) add the lock entry, with its thread id (TID) in the bottom 29 bits 141 3) add the lock entry, with its thread id (TID) in the bottom 29 bits
@@ -143,7 +143,7 @@ On insertion:
143 4) clear the 'list_op_pending' word. 143 4) clear the 'list_op_pending' word.
144 144
145On removal: 145On removal:
146 1) set the 'list_op_pending' word to the address of the 'lock word' 146 1) set the 'list_op_pending' word to the address of the 'lock entry'
147 to be removed, 147 to be removed,
148 2) remove the lock entry for this lock from the 'head' list, 148 2) remove the lock entry for this lock from the 'head' list,
149 2) release the futex lock, and 149 2) release the futex lock, and
diff --git a/Documentation/watchdog/hpwdt.txt b/Documentation/watchdog/hpwdt.txt
new file mode 100644
index 000000000000..127839e53043
--- /dev/null
+++ b/Documentation/watchdog/hpwdt.txt
@@ -0,0 +1,84 @@
1Last reviewed: 06/02/2009
2
3 HP iLO2 NMI Watchdog Driver
4 NMI sourcing for iLO2 based ProLiant Servers
5 Documentation and Driver by
6 Thomas Mingarelli <thomas.mingarelli@hp.com>
7
8 The HP iLO2 NMI Watchdog driver is a kernel module that provides basic
9 watchdog functionality and the added benefit of NMI sourcing. Both the
10 watchdog functionality and the NMI sourcing capability need to be enabled
11 by the user. Remember that the two modes are not dependant on one another.
12 A user can have the NMI sourcing without the watchdog timer and vice-versa.
13
14 Watchdog functionality is enabled like any other common watchdog driver. That
15 is, an application needs to be started that kicks off the watchdog timer. A
16 basic application exists in the Documentation/watchdog/src directory called
17 watchdog-test.c. Simply compile the C file and kick it off. If the system
18 gets into a bad state and hangs, the HP ProLiant iLO 2 timer register will
19 not be updated in a timely fashion and a hardware system reset (also known as
20 an Automatic Server Recovery (ASR)) event will occur.
21
22 The hpwdt driver also has three (3) module parameters. They are the following:
23
24 soft_margin - allows the user to set the watchdog timer value
25 allow_kdump - allows the user to save off a kernel dump image after an NMI
26 nowayout - basic watchdog parameter that does not allow the timer to
27 be restarted or an impending ASR to be escaped.
28
29 NOTE: More information about watchdog drivers in general, including the ioctl
30 interface to /dev/watchdog can be found in
31 Documentation/watchdog/watchdog-api.txt and Documentation/IPMI.txt.
32
33 The NMI sourcing capability is disabled when the driver discovers that the
34 nmi_watchdog is turned on (nmi_watchdog = 1). This is due to the inability to
35 distinguish between "NMI Watchdog Ticks" and "HW generated NMI events" in the
36 Linux kernel. What this means is that the hpwdt nmi handler code is called
37 each time the NMI signal fires off. This could amount to several thousands of
38 NMIs in a matter of seconds. If a user sees the Linux kernel's "dazed and
39 confused" message in the logs or if the system gets into a hung state, then
40 the user should reboot with nmi_watchdog=0.
41
42 1. If the kernel has not been booted with nmi_watchdog turned off then
43 edit /boot/grub/menu.lst and place the nmi_watchdog=0 at the end of the
44 currently booting kernel line.
45 2. reboot the sever
46
47 Now, the hpwdt can successfully receive and source the NMI and provide a log
48 message that details the reason for the NMI (as determined by the HP BIOS).
49
50 Below is a list of NMIs the HP BIOS understands along with the associated
51 code (reason):
52
53 No source found 00h
54
55 Uncorrectable Memory Error 01h
56
57 ASR NMI 1Bh
58
59 PCI Parity Error 20h
60
61 NMI Button Press 27h
62
63 SB_BUS_NMI 28h
64
65 ILO Doorbell NMI 29h
66
67 ILO IOP NMI 2Ah
68
69 ILO Watchdog NMI 2Bh
70
71 Proc Throt NMI 2Ch
72
73 Front Side Bus NMI 2Dh
74
75 PCI Express Error 2Fh
76
77 DMA controller NMI 30h
78
79 Hypertransport/CSI Error 31h
80
81
82
83 -- Tom Mingarelli
84 (thomas.mingarelli@hp.com)