proc.txt: update kernel filesystem/proc.txt documentation

An update for the "Process-Specific Subdirectories" section to reflect the
changes till kernel 2.6.30.
Signed-off-by: NStefani Seibold <stefani@seibold.net>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Documentation/filesystems/proc.txt

@@ -5,11 +5,12 @@
                   Bodo Bauer <bb@ricochet.net>
 
 2.4.x update	  Jorge Nerin <comandante@zaralinux.com>      November 14 2000
-move /proc/sys	  Shen Feng <shen@cn.fujitsu.com>		    April 1 2009
+move /proc/sys	  Shen Feng <shen@cn.fujitsu.com>		  April 1 2009
 ------------------------------------------------------------------------------
 Version 1.3                                              Kernel version 2.2.12
 					      Kernel version 2.4.0-test11-pre4
 ------------------------------------------------------------------------------
+fixes/update part 1.1  Stefani Seibold <stefani@seibold.net>       June 9 2009
 
 Table of Contents
 -----------------
@@ -116,7 +117,7 @@ The link  self  points  to  the  process reading the file system. Each process
 subdirectory has the entries listed in Table 1-1.
 
 
-Table 1-1: Process specific entries in /proc 
+Table 1-1: Process specific entries in /proc
 ..............................................................................
  File		Content
  clear_refs	Clears page referenced bits shown in smaps output
@@ -134,46 +135,103 @@ Table 1-1: Process specific entries in /proc
  status		Process status in human readable form
  wchan		If CONFIG_KALLSYMS is set, a pre-decoded wchan
  stack		Report full stack trace, enable via CONFIG_STACKTRACE
- smaps		Extension based on maps, the rss size for each mapped file
+ smaps		a extension based on maps, showing the memory consumption of
+		each mapping
 ..............................................................................
 
 For example, to get the status information of a process, all you have to do is
 read the file /proc/PID/status:
 
-  >cat /proc/self/status 
-  Name:   cat 
-  State:  R (running) 
-  Pid:    5452 
-  PPid:   743 
+  >cat /proc/self/status
+  Name:   cat
+  State:  R (running)
+  Tgid:   5452
+  Pid:    5452
+  PPid:   743
   TracerPid:      0						(2.4)
-  Uid:    501     501     501     501 
-  Gid:    100     100     100     100 
-  Groups: 100 14 16 
-  VmSize:     1112 kB 
-  VmLck:         0 kB 
-  VmRSS:       348 kB 
-  VmData:       24 kB 
-  VmStk:        12 kB 
-  VmExe:         8 kB 
-  VmLib:      1044 kB 
-  SigPnd: 0000000000000000 
-  SigBlk: 0000000000000000 
-  SigIgn: 0000000000000000 
-  SigCgt: 0000000000000000 
-  CapInh: 00000000fffffeff 
-  CapPrm: 0000000000000000 
-  CapEff: 0000000000000000 
-
+  Uid:    501     501     501     501
+  Gid:    100     100     100     100
+  FDSize: 256
+  Groups: 100 14 16
+  VmPeak:     5004 kB
+  VmSize:     5004 kB
+  VmLck:         0 kB
+  VmHWM:       476 kB
+  VmRSS:       476 kB
+  VmData:      156 kB
+  VmStk:        88 kB
+  VmExe:        68 kB
+  VmLib:      1412 kB
+  VmPTE:        20 kb
+  Threads:        1
+  SigQ:   0/28578
+  SigPnd: 0000000000000000
+  ShdPnd: 0000000000000000
+  SigBlk: 0000000000000000
+  SigIgn: 0000000000000000
+  SigCgt: 0000000000000000
+  CapInh: 00000000fffffeff
+  CapPrm: 0000000000000000
+  CapEff: 0000000000000000
+  CapBnd: ffffffffffffffff
+  voluntary_ctxt_switches:        0
+  nonvoluntary_ctxt_switches:     1
 
 This shows you nearly the same information you would get if you viewed it with
 the ps  command.  In  fact,  ps  uses  the  proc  file  system  to  obtain its
-information. The  statm  file  contains  more  detailed  information about the
-process memory usage. Its seven fields are explained in Table 1-2.  The stat
-file contains details information about the process itself.  Its fields are
-explained in Table 1-3.
+information.  But you get a more detailed  view of the  process by reading the
+file /proc/PID/status. It fields are described in table 1-2.
+
+The  statm  file  contains  more  detailed  information about the process
+memory usage. Its seven fields are explained in Table 1-3.  The stat file
+contains details information about the process itself.  Its fields are
+explained in Table 1-4.
 
+Table 1-2: Contents of the statm files (as of 2.6.30-rc7)
+..............................................................................
+ Field                       Content
+ Name                        filename of the executable
+ State                       state (R is running, S is sleeping, D is sleeping
+                             in an uninterruptible wait, Z is zombie,
+			     T is traced or stopped)
+ Tgid                        thread group ID
+ Pid                         process id
+ PPid                        process id of the parent process
+ TracerPid                   PID of process tracing this process (0 if not)
+ Uid                         Real, effective, saved set, and  file system UIDs
+ Gid                         Real, effective, saved set, and  file system GIDs
+ FDSize                      number of file descriptor slots currently allocated
+ Groups                      supplementary group list
+ VmPeak                      peak virtual memory size
+ VmSize                      total program size
+ VmLck                       locked memory size
+ VmHWM                       peak resident set size ("high water mark")
+ VmRSS                       size of memory portions
+ VmData                      size of data, stack, and text segments
+ VmStk                       size of data, stack, and text segments
+ VmExe                       size of text segment
+ VmLib                       size of shared library code
+ VmPTE                       size of page table entries
+ Threads                     number of threads
+ SigQ                        number of signals queued/max. number for queue
+ SigPnd                      bitmap of pending signals for the thread
+ ShdPnd                      bitmap of shared pending signals for the process
+ SigBlk                      bitmap of blocked signals
+ SigIgn                      bitmap of ignored signals
+ SigCgt                      bitmap of catched signals
+ CapInh                      bitmap of inheritable capabilities
+ CapPrm                      bitmap of permitted capabilities
+ CapEff                      bitmap of effective capabilities
+ CapBnd                      bitmap of capabilities bounding set
+ Cpus_allowed                mask of CPUs on which this process may run
+ Cpus_allowed_list           Same as previous, but in "list format"
+ Mems_allowed                mask of memory nodes allowed to this process
+ Mems_allowed_list           Same as previous, but in "list format"
+ voluntary_ctxt_switches     number of voluntary context switches
+ nonvoluntary_ctxt_switches  number of non voluntary context switches
+..............................................................................
 
-Table 1-2: Contents of the statm files (as of 2.6.8-rc3)
+Table 1-3: Contents of the statm files (as of 2.6.8-rc3)
 ..............................................................................
  Field    Content
  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)
 ..............................................................................
 
 
-Table 1-3: Contents of the stat files (as of 2.6.22-rc3)
+Table 1-4: Contents of the stat files (as of 2.6.30-rc7)
 ..............................................................................
  Field          Content
   pid           process id
@@ -222,10 +280,10 @@ Table 1-3: Contents of the stat files (as of 2.6.22-rc3)
   start_stack   address of the start of the stack
   esp           current value of ESP
   eip           current value of EIP
-  pending       bitmap of pending signals (obsolete)
-  blocked       bitmap of blocked signals (obsolete)
-  sigign        bitmap of ignored signals (obsolete)
-  sigcatch      bitmap of catched signals (obsolete)
+  pending       bitmap of pending signals
+  blocked       bitmap of blocked signals
+  sigign        bitmap of ignored signals
+  sigcatch      bitmap of catched signals
   wchan         address where process went to sleep
   0             (place holder)
   0             (place holder)
@@ -234,19 +292,99 @@ Table 1-3: Contents of the stat files (as of 2.6.22-rc3)
   rt_priority   realtime priority
   policy        scheduling policy (man sched_setscheduler)
   blkio_ticks   time spent waiting for block IO
+  gtime         guest time of the task in jiffies
+  cgtime        guest time of the task children in jiffies
 ..............................................................................
 
+The /proc/PID/map file containing the currently mapped memory regions and
+their access permissions.
+
+The format is:
+
+address           perms offset  dev   inode      pathname
+
+08048000-08049000 r-xp 00000000 03:00 8312       /opt/test
+08049000-0804a000 rw-p 00001000 03:00 8312       /opt/test
+0804a000-0806b000 rw-p 00000000 00:00 0          [heap]
+a7cb1000-a7cb2000 ---p 00000000 00:00 0
+a7cb2000-a7eb2000 rw-p 00000000 00:00 0
+a7eb2000-a7eb3000 ---p 00000000 00:00 0
+a7eb3000-a7ed5000 rw-p 00000000 00:00 0
+a7ed5000-a8008000 r-xp 00000000 03:00 4222       /lib/libc.so.6
+a8008000-a800a000 r--p 00133000 03:00 4222       /lib/libc.so.6
+a800a000-a800b000 rw-p 00135000 03:00 4222       /lib/libc.so.6
+a800b000-a800e000 rw-p 00000000 00:00 0
+a800e000-a8022000 r-xp 00000000 03:00 14462      /lib/libpthread.so.0
+a8022000-a8023000 r--p 00013000 03:00 14462      /lib/libpthread.so.0
+a8023000-a8024000 rw-p 00014000 03:00 14462      /lib/libpthread.so.0
+a8024000-a8027000 rw-p 00000000 00:00 0
+a8027000-a8043000 r-xp 00000000 03:00 8317       /lib/ld-linux.so.2
+a8043000-a8044000 r--p 0001b000 03:00 8317       /lib/ld-linux.so.2
+a8044000-a8045000 rw-p 0001c000 03:00 8317       /lib/ld-linux.so.2
+aff35000-aff4a000 rw-p 00000000 00:00 0          [stack]
+ffffe000-fffff000 r-xp 00000000 00:00 0          [vdso]
+
+where "address" is the address space in the process that it occupies, "perms"
+is a set of permissions:
+
+ r = read
+ w = write
+ x = execute
+ s = shared
+ p = private (copy on write)
+
+"offset" is the offset into the mapping, "dev" is the device (major:minor), and
+"inode" is the inode  on that device.  0 indicates that  no inode is associated
+with the memory region, as the case would be with BSS (uninitialized data).
+The "pathname" shows the name associated file for this mapping.  If the mapping
+is not associated with a file:
+
+ [heap]                   = the heap of the program
+ [stack]                  = the stack of the main process
+ [vdso]                   = the "virtual dynamic shared object",
+                            the kernel system call handler
+
+ or if empty, the mapping is anonymous.
+
+
+The /proc/PID/smaps is an extension based on maps, showing the memory
+consumption for each of the process's mappings. For each of mappings there
+is a series of lines such as the following:
+
+08048000-080bc000 r-xp 00000000 03:02 13130      /bin/bash
+Size:               1084 kB
+Rss:                 892 kB
+Pss:                 374 kB
+Shared_Clean:        892 kB
+Shared_Dirty:          0 kB
+Private_Clean:         0 kB
+Private_Dirty:         0 kB
+Referenced:          892 kB
+Swap:                  0 kB
+KernelPageSize:        4 kB
+MMUPageSize:           4 kB
+
+The first  of these lines shows  the same information  as is displayed for the
+mapping in /proc/PID/maps.  The remaining lines show  the size of the mapping,
+the amount of the mapping that is currently resident in RAM, the "proportional
+set size” (divide each shared page by the number of processes sharing it), the
+number of clean and dirty shared pages in the mapping, and the number of clean
+and dirty private pages in the mapping.  The "Referenced" indicates the amount
+of memory currently marked as referenced or accessed.
+
+This file is only present if the CONFIG_MMU kernel configuration option is
+enabled.
 
 1.2 Kernel data
 ---------------
 
 Similar to  the  process entries, the kernel data files give information about
 the running kernel. The files used to obtain this information are contained in
-/proc and  are  listed  in Table 1-4. Not all of these will be present in your
+/proc and  are  listed  in Table 1-5. Not all of these will be present in your
 system. It  depends  on the kernel configuration and the loaded modules, which
 files are there, and which are missing.
 
-Table 1-4: Kernel info in /proc
+Table 1-5: Kernel info in /proc
 ..............................................................................
  File        Content                                           
  apm         Advanced power management info                    
@@ -634,10 +772,10 @@ IDE devices:
 
 More detailed  information  can  be  found  in  the  controller  specific
 subdirectories. These  are  named  ide0,  ide1  and  so  on.  Each  of  these
-directories contains the files shown in table 1-5.
+directories contains the files shown in table 1-6.
 
 
-Table 1-5: IDE controller info in  /proc/ide/ide?
+Table 1-6: IDE controller info in  /proc/ide/ide?
 ..............................................................................
  File    Content                                 
  channel IDE channel (0 or 1)                    
@@ -647,11 +785,11 @@ Table 1-5: IDE controller info in  /proc/ide/ide?
 ..............................................................................
 
 Each device  connected  to  a  controller  has  a separate subdirectory in the
-controllers directory.  The  files  listed in table 1-6 are contained in these
+controllers directory.  The  files  listed in table 1-7 are contained in these
 directories.
 
 
-Table 1-6: IDE device information
+Table 1-7: IDE device information
 ..............................................................................
  File             Content                                    
  cache            The cache                                  
@@ -693,12 +831,12 @@ the drive parameters:
 1.4 Networking info in /proc/net
 --------------------------------
 
-The subdirectory  /proc/net  follows  the  usual  pattern. Table 1-6 shows the
+The subdirectory  /proc/net  follows  the  usual  pattern. Table 1-8 shows the
 additional values  you  get  for  IP  version 6 if you configure the kernel to
-support this. Table 1-7 lists the files and their meaning.
+support this. Table 1-9 lists the files and their meaning.
 
 
-Table 1-6: IPv6 info in /proc/net 
+Table 1-8: IPv6 info in /proc/net
 ..............................................................................
  File       Content                                               
  udp6       UDP sockets (IPv6)                                    
@@ -713,7 +851,7 @@ Table 1-6: IPv6 info in /proc/net
 ..............................................................................
 
 
-Table 1-7: Network info in /proc/net 
+Table 1-9: Network info in /proc/net
 ..............................................................................
  File          Content                                                         
  arp           Kernel  ARP table                                               
@@ -837,10 +975,10 @@ The directory  /proc/parport  contains information about the parallel ports of
 your system.  It  has  one  subdirectory  for  each port, named after the port
 number (0,1,2,...).
 
-These directories contain the four files shown in Table 1-8.
+These directories contain the four files shown in Table 1-10.
 
 
-Table 1-8: Files in /proc/parport 
+Table 1-10: Files in /proc/parport
 ..............................................................................
  File      Content                                                             
  autoprobe Any IEEE-1284 device ID information that has been acquired.         
@@ -858,10 +996,10 @@ Table 1-8: Files in /proc/parport
 
 Information about  the  available  and actually used tty's can be found in the
 directory /proc/tty.You'll  find  entries  for drivers and line disciplines in
-this directory, as shown in Table 1-9.
+this directory, as shown in Table 1-11.
 
 
-Table 1-9: Files in /proc/tty 
+Table 1-11: Files in /proc/tty
 ..............................................................................
  File          Content                                        
  drivers       list of drivers and their usage                
@@ -952,9 +1090,9 @@ Information about mounted ext4 file systems can be found in
 /proc/fs/ext4.  Each mounted filesystem will have a directory in
 /proc/fs/ext4 based on its device name (i.e., /proc/fs/ext4/hdc or
 /proc/fs/ext4/dm-0).   The files in each per-device directory are shown
-in Table 1-10, below.
+in Table 1-12, below.
 
-Table 1-10: Files in /proc/fs/ext4/<devname>
+Table 1-12: Files in /proc/fs/ext4/<devname>
 ..............................................................................
  File            Content                                        
  mb_groups       details of multiblock allocator buddy cache of free blocks