From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754287AbbIMLHA (ORCPT ); Sun, 13 Sep 2015 07:07:00 -0400 Received: from terminus.zytor.com ([198.137.202.10]:43650 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752307AbbIMLG7 (ORCPT ); Sun, 13 Sep 2015 07:06:59 -0400 Date: Sun, 13 Sep 2015 04:06:17 -0700 From: tip-bot for Dietmar Eggemann Message-ID: Cc: daniel.lezcano@linaro.org, linux-kernel@vger.kernel.org, mturquette@baylibre.com, mingo@kernel.org, rjw@rjwysocki.net, sgurrappadi@nvidia.com, vincent.guittot@linaro.org, peterz@infradead.org, Juri.Lelli@arm.com, pang.xunlei@zte.com.cn, efault@gmx.de, dietmar.eggemann@arm.com, tglx@linutronix.de, yuyang.du@intel.com, torvalds@linux-foundation.org, hpa@zytor.com Reply-To: vincent.guittot@linaro.org, Juri.Lelli@arm.com, peterz@infradead.org, pang.xunlei@zte.com.cn, mturquette@baylibre.com, linux-kernel@vger.kernel.org, daniel.lezcano@linaro.org, mingo@kernel.org, rjw@rjwysocki.net, sgurrappadi@nvidia.com, tglx@linutronix.de, yuyang.du@intel.com, hpa@zytor.com, torvalds@linux-foundation.org, dietmar.eggemann@arm.com, efault@gmx.de In-Reply-To: <55EDA2E9.8040900@arm.com> References: <55EDA2E9.8040900@arm.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] sched/fair: Defer calling scaling functions Git-Commit-ID: 6f2b04524f0b38bfbb8413f98d2d6af234508309 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 6f2b04524f0b38bfbb8413f98d2d6af234508309 Gitweb: http://git.kernel.org/tip/6f2b04524f0b38bfbb8413f98d2d6af234508309 Author: Dietmar Eggemann AuthorDate: Mon, 7 Sep 2015 14:57:22 +0100 Committer: Ingo Molnar CommitDate: Sun, 13 Sep 2015 09:53:01 +0200 sched/fair: Defer calling scaling functions Do not call the scaling functions in case time goes backwards or the last update of the sched_avg structure has happened less than 1024ns ago. Signed-off-by: Dietmar Eggemann Signed-off-by: Peter Zijlstra (Intel) Cc: Juri Lelli Cc: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: daniel.lezcano@linaro.org Cc: mturquette@baylibre.com Cc: pang.xunlei@zte.com.cn Cc: rjw@rjwysocki.net Cc: sgurrappadi@nvidia.com Cc: vincent.guittot@linaro.org Cc: yuyang.du@intel.com Link: http://lkml.kernel.org/r/55EDA2E9.8040900@arm.com Signed-off-by: Ingo Molnar --- kernel/sched/fair.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index c3c5585..fc835fa 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -2552,8 +2552,7 @@ __update_load_avg(u64 now, int cpu, struct sched_avg *sa, u64 delta, scaled_delta, periods; u32 contrib; unsigned int delta_w, scaled_delta_w, decayed = 0; - unsigned long scale_freq = arch_scale_freq_capacity(NULL, cpu); - unsigned long scale_cpu = arch_scale_cpu_capacity(NULL, cpu); + unsigned long scale_freq, scale_cpu; delta = now - sa->last_update_time; /* @@ -2574,6 +2573,9 @@ __update_load_avg(u64 now, int cpu, struct sched_avg *sa, return 0; sa->last_update_time = now; + scale_freq = arch_scale_freq_capacity(NULL, cpu); + scale_cpu = arch_scale_cpu_capacity(NULL, cpu); + /* delta_w is the amount already accumulated against our next period */ delta_w = sa->period_contrib; if (delta + delta_w >= 1024) {