From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752619AbdK3P5e (ORCPT ); Thu, 30 Nov 2017 10:57:34 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:56728 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751936AbdK3P5d (ORCPT ); Thu, 30 Nov 2017 10:57:33 -0500 Date: Thu, 30 Nov 2017 15:57:28 +0000 From: Patrick Bellasi To: Juri Lelli Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, Ingo Molnar , Peter Zijlstra , "Rafael J . Wysocki" , Viresh Kumar , Vincent Guittot , Dietmar Eggemann , Morten Rasmussen , Todd Kjos , Joel Fernandes Subject: Re: [PATCH v3 3/6] cpufreq: schedutil: update CFS util only if used Message-ID: <20171130155728.GF31247@e110439-lin> References: <20171130114723.29210-1-patrick.bellasi@arm.com> <20171130114723.29210-4-patrick.bellasi@arm.com> <20171130132234.GC9903@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171130132234.GC9903@localhost.localdomain> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 30-Nov 14:22, Juri Lelli wrote: > Hi, > > On 30/11/17 11:47, Patrick Bellasi wrote: > > Currently the utilization of the FAIR class is collected before locking > > the policy. Although that should not be a big issue for most cases, we > > also don't really know how much latency there can be between the > > utilization reading and its usage. > > > > Let's get the FAIR utilization right before its usage to be better in > > sync with the current status of a CPU. > > > > Signed-off-by: Patrick Bellasi > > Reviewed-by: Dietmar Eggemann > > Cc: Ingo Molnar > > Cc: Peter Zijlstra > > Cc: Rafael J. Wysocki > > Cc: Viresh Kumar > > Cc: linux-kernel@vger.kernel.org > > Cc: linux-pm@vger.kernel.org > > > > --- > > Changes from v2: > > - rebased on v4.15-rc1 > > > > Change-Id: I9291a560bcad7db76894e3f0fcdb917511d0479e > > --- > > kernel/sched/cpufreq_schedutil.c | 3 +-- > > 1 file changed, 1 insertion(+), 2 deletions(-) > > > > diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c > > index 448f49de5335..40521d59630b 100644 > > --- a/kernel/sched/cpufreq_schedutil.c > > +++ b/kernel/sched/cpufreq_schedutil.c > > @@ -351,10 +351,9 @@ static void sugov_update_shared(struct update_util_data *hook, u64 time, > > unsigned int next_f; > > bool rt_mode; > > > > - sugov_get_util(&util, &max, sg_cpu->cpu); > > - > > raw_spin_lock(&sg_policy->update_lock); > > > > + sugov_get_util(&util, &max, sg_cpu->cpu); > > sg_cpu->util = util; > > sg_cpu->max = max; > > Patch looks good. > > Reviewed-by: Juri Lelli > > However, not sure $SUBJECT is really in sync with what the patch does? > CFS gets "used" before and after the patch... last paragraph of the > changelog looks more like it. :) Yes, that's a pretty trivial update with a confusing changelog. If we think it's worth to keep (and correct as well) I'll update the commit message. Thanks for poinint that out. > Best, > > Juri Cheers Patrick -- #include Patrick Bellasi