[PATCH] Documentation: add descs for guest fields in stat procfs files

[AP <ap@zip.com.au>]

Git patch 5e84cfde51cf303d368fcb48f22059f37b3872de introduced a new
field to /proc/stat that represents guest (virtual cpu) time.

Git patch 9ac52315d4cf5f561f36dabaf0720c00d3553162 introduced the same
to /proc/<pid>/stat along with a guest time of the tasks children.

The patch below adds descriptions of these fields to the procfs
documentation included in the kernel.

Signed-Off-By: Andrew P <ap@zip.com.au>

diff -aur linux-2.6.26-rc7-git2.orig/Documentation/filesystems/proc.txt linux-2.6.26-rc7-git2/Documentation/filesystems/proc.txt
--- linux-2.6.26-rc7-git2.orig/Documentation/filesystems/proc.txt	2008-06-23 22:27:13.000000000 +1000
+++ linux-2.6.26-rc7-git2/Documentation/filesystems/proc.txt	2008-06-24 22:16:53.000000000 +1000
@@ -210,9 +210,9 @@
   cmin_flt      number of minor faults with child's
   maj_flt       number of major faults
   cmaj_flt      number of major faults with child's
-  utime         user mode jiffies
+  utime         user mode jiffies (including gtime below*)
   stime         kernel mode jiffies
-  cutime        user mode jiffies with child's
+  cutime        user mode jiffies with child's (including cgtime below*)
   cstime        kernel mode jiffies with child's
   priority      priority level
   nice          nice level
@@ -239,6 +239,11 @@
   rt_priority   realtime priority
   policy        scheduling policy (man sched_setscheduler)
   blkio_ticks   time spent waiting for block IO
+  gtime         guest (virtual CPU) CPU time in jiffies
+  cgtime        guests' children's CPU time in jiffies
+
+* gtime and cgtime are included in these values so that applications that are
+  not aware of these fields do not lose time in their calculations.
 ..............................................................................
 
 
@@ -828,9 +833,9 @@
 since the system first booted.  For a quick look, simply cat the file:
 
   > cat /proc/stat
-  cpu  2255 34 2290 22625563 6290 127 456 0
-  cpu0 1132 34 1441 11311718 3675 127 438 0
-  cpu1 1123 0 849 11313845 2614 0 18 0
+  cpu  2255 34 2290 22625563 6290 127 456 0 0
+  cpu0 1132 34 1441 11311718 3675 127 438 0 0
+  cpu1 1123 0 849 11313845 2614 0 18 0 0
   intr 114930548 113199788 3 0 5 263 0 4 [... lots more numbers ...]
   ctxt 1990473
   btime 1062191376
@@ -843,7 +848,8 @@
 different kinds of work.  Time units are in USER_HZ (typically hundredths of a
 second).  The meanings of the columns are as follows, from left to right:
 
-- user: normal processes executing in user mode
+- user: normal processes executing in user mode (includes guest time below so
+        that guest-unaware applications do not lose time)
 - nice: niced processes executing in user mode
 - system: processes executing in kernel mode
 - idle: twiddling thumbs
@@ -851,6 +857,7 @@
 - irq: servicing interrupts
 - softirq: servicing softirqs
 - steal: involuntary wait
+- guest: time used to run a virtual CPU
 
 The "intr" line gives counts of interrupts  serviced since boot time, for each
 of the  possible system interrupts.   The first  column  is the  total of  all