Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758590Ab3D3DRs (ORCPT ); Mon, 29 Apr 2013 23:17:48 -0400 Received: from mail-qc0-f177.google.com ([209.85.216.177]:52072 "EHLO mail-qc0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758522Ab3D3DRp (ORCPT ); Mon, 29 Apr 2013 23:17:45 -0400 From: kosaki.motohiro@gmail.com To: linux-kernel@vger.kernel.org Cc: Olivier Langlois , Martin Schwidefsky , Steven Rostedt , David Miller , Thomas Gleixner , Frederic Weisbecker , Ingo Molnar , Peter Zijlstra , KOSAKI Motohiro Subject: [PATCH 04/10] posix-cpu-timers: don't account cpu timer after stopped thread runtime accounting Date: Mon, 29 Apr 2013 23:17:12 -0400 Message-Id: <1367291838-5490-5-git-send-email-kosaki.motohiro@gmail.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1367291838-5490-1-git-send-email-kosaki.motohiro@gmail.com> References: <1367291838-5490-1-git-send-email-kosaki.motohiro@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1507 Lines: 44 From: KOSAKI Motohiro When tsk->signal->cputimer->running is 1, signal->cputimer and tsk->sum_sched_runtime increase the same pace. update_curr() increase both account. However, there is one exeception. When thread exiting, __exit_signal() turns over task's sum_shced_runtime to sig->sum_sched_runtime. but it doesn't stop signal->cputimer accounting. This inconsistency makes too early POSIX timer wakeup. Fix it. Signed-off-by: Olivier Langlois Signed-off-by: KOSAKI Motohiro --- kernel/sched/stats.h | 7 +++++++ 1 files changed, 7 insertions(+), 0 deletions(-) diff --git a/kernel/sched/stats.h b/kernel/sched/stats.h index 2ef90a5..5a0cfc4 100644 --- a/kernel/sched/stats.h +++ b/kernel/sched/stats.h @@ -225,6 +225,13 @@ static inline void account_group_exec_runtime(struct task_struct *tsk, if (!cputimer->running) return; + /* + * After turning over se.sum_exec_runtime to sig->sum_sched_runtime + * in __exit_signal(), we must not account exec_runtime for consistency. + */ + if (unlikely(!tsk->sighand)) + return; + raw_spin_lock(&cputimer->lock); cputimer->cputime.sum_exec_runtime += ns; raw_spin_unlock(&cputimer->lock); -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/