[tip:sched/urgent] sched/cputime: Fix accounting on multi-threaded processes

[tip-bot for Stanislaw Gruszka <tipbot@zytor.com>]

Commit-ID:  e614b3332a4f3f264a26da28e5a1f4cc3aea3974
Gitweb:     http://git.kernel.org/tip/e614b3332a4f3f264a26da28e5a1f4cc3aea3974
Author:     Stanislaw Gruszka <sgruszka@redhat.com>
AuthorDate: Thu, 4 Apr 2013 10:57:48 +0200
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Mon, 8 Apr 2013 17:40:52 +0200

sched/cputime: Fix accounting on multi-threaded processes

Recent commit 6fac4829 ("cputime: Use accessors to read task
cputime stats") introduced a bug, where we account many times
the cputime of the first thread, instead of cputimes of all
the different threads.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20130404085740.GA2495@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 kernel/sched/cputime.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index ed12cbb..e93cca9 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -310,7 +310,7 @@ void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
 
 	t = tsk;
 	do {
-		task_cputime(tsk, &utime, &stime);
+		task_cputime(t, &utime, &stime);
 		times->utime += utime;
 		times->stime += stime;
 		times->sum_exec_runtime += task_sched_runtime(t);