From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752256Ab3FJH6L (ORCPT ); Mon, 10 Jun 2013 03:58:11 -0400 Received: from mx1.redhat.com ([209.132.183.28]:6729 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751477Ab3FJH5y (ORCPT ); Mon, 10 Jun 2013 03:57:54 -0400 Date: Mon, 10 Jun 2013 15:57:45 +0800 From: Dong Zhu To: John Stultz , Thomas Gleixner Cc: linux-kernel@vger.kernel.org Subject: [PATCH] timer stats: reset entries when disable the timer usage statistics Message-ID: <20130610075745.GK8399@zhudong.nay.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>From 4dbb760213856dc382241db456c1c6487694837c Mon Sep 17 00:00:00 2001 From: Dong Zhu Date: Mon, 10 Jun 2013 15:09:27 +0800 we can start/stop data collection by using : echo [1|0] > /proc/timer_stats when we stop the data collection,hrtimer will not update the statistics for a timer any more,but we could still check the timer usage statistics,unfortunately the data is not the latest, the inaccurate data might make us confusing. So the purpose of this patch is to reset the entries once disable operation is executed.In this way we will never see the inaccurate timer usage statistics. Signed-off-by: Dong Zhu --- kernel/time/timer_stats.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/time/timer_stats.c b/kernel/time/timer_stats.c index 0b537f2..43f05e7 100644 --- a/kernel/time/timer_stats.c +++ b/kernel/time/timer_stats.c @@ -371,6 +371,7 @@ static ssize_t tstats_write(struct file *file, const char __user *buf, switch (ctl[0]) { case '0': if (timer_stats_active) { + reset_entries(); timer_stats_active = 0; time_stop = ktime_get(); sync_access(); -- 1.7.11.7 -- Best Regards, Dong Zhu