From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754969Ab0EJFyI (ORCPT ); Mon, 10 May 2010 01:54:08 -0400 Received: from hera.kernel.org ([140.211.167.34]:33846 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754046Ab0EJFyE (ORCPT ); Mon, 10 May 2010 01:54:04 -0400 Date: Mon, 10 May 2010 05:53:09 GMT From: tip-bot for Arjan van de Ven Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, a.p.zijlstra@chello.nl, arjan@linux.intel.com, riel@redhat.com, akpm@linux-foundation.org, tglx@linutronix.de, mingo@elte.hu Reply-To: riel@redhat.com, mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, arjan@linux.intel.com, a.p.zijlstra@chello.nl, tglx@linutronix.de, mingo@elte.hu In-Reply-To: <20100509082323.2d2f1945@infradead.org> References: <20100509082323.2d2f1945@infradead.org> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] sched: Update the idle statistics in get_cpu_idle_time_us() Message-ID: Git-Commit-ID: 8c7b09f43f4bf570654bcc458ce96819a932303c X-Mailer: tip-git-log-daemon MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.3 (hera.kernel.org [127.0.0.1]); Mon, 10 May 2010 05:53:10 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 8c7b09f43f4bf570654bcc458ce96819a932303c Gitweb: http://git.kernel.org/tip/8c7b09f43f4bf570654bcc458ce96819a932303c Author: Arjan van de Ven AuthorDate: Sun, 9 May 2010 08:23:23 -0700 Committer: Ingo Molnar CommitDate: Sun, 9 May 2010 19:35:26 +0200 sched: Update the idle statistics in get_cpu_idle_time_us() Right now, get_cpu_idle_time_us() only reports the idle statistics upto the point the CPU entered last idle; not what is valid right now. This patch adds an update of the idle statistics to get_cpu_idle_time_us(), so that calling this function always returns statistics that are accurate at the point of the call. This includes resetting the start of the idle time for accounting purposes to avoid double accounting. Signed-off-by: Arjan van de Ven Signed-off-by: Andrew Morton Reviewed-by: Rik van Riel Acked-by: Peter Zijlstra Cc: davej@redhat.com LKML-Reference: <20100509082323.2d2f1945@infradead.org> Signed-off-by: Ingo Molnar --- kernel/time/tick-sched.c | 7 ++++++- 1 files changed, 6 insertions(+), 1 deletions(-) diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 59d8762..f15d18d 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -161,6 +161,7 @@ static void update_ts_time_stats(struct tick_sched *ts, ktime_t now) if (ts->idle_active) { delta = ktime_sub(now, ts->idle_entrytime); ts->idle_sleeptime = ktime_add(ts->idle_sleeptime, delta); + ts->idle_entrytime = now; } } @@ -205,14 +206,18 @@ static ktime_t tick_nohz_start_idle(struct tick_sched *ts) u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time) { struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); + ktime_t now; if (!tick_nohz_enabled) return -1; + now = ktime_get(); + update_ts_time_stats(ts, now); + if (ts->idle_active) *last_update_time = ktime_to_us(ts->idle_lastupdate); else - *last_update_time = ktime_to_us(ktime_get()); + *last_update_time = ktime_to_us(now); return ktime_to_us(ts->idle_sleeptime); }