[PATCH] pacct: none-delayed process accounting accumulation

In current 2.6.17 implementation, signal_struct refered from task_struct is
used for per-process data structure.  The pacct facility also uses it as a
per-process data structure to store stime, utime, minflt, majflt.  But those
members are saved in __exit_signal().  It's too late.

For example, if some threads exits at same time, pacct facility has a
possibility to drop accountings for a part of those threads.  (see, the
following 'The results of original 2.6.17 kernel') I think accounting
information should be completely collected into the per-process data structure
before writing out an accounting record.

This patch fixes this matter.  Accumulation of stime, utime, minflt and majflt
are done before generating accounting record.

[mingo@elte.hu: fix acct_collect() siglock bug found by lockdep]
Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index d8429dc250f0..8d11d9310db0 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -362,6 +362,8 @@ struct pacct_struct {
         int                     ac_flag;
         long                    ac_exitcode;
         unsigned long           ac_mem;
+        cputime_t               ac_utime, ac_stime;
+        unsigned long           ac_minflt, ac_majflt;
 };
 
 /*