Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752855AbbHPWCR (ORCPT ); Sun, 16 Aug 2015 18:02:17 -0400 Received: from casper.infradead.org ([85.118.1.10]:55471 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751429AbbHPWBq (ORCPT ); Sun, 16 Aug 2015 18:01:46 -0400 Date: Sun, 16 Aug 2015 22:24:01 +0200 From: Peter Zijlstra To: Michael Turquette Cc: Morten Rasmussen , mingo@redhat.com, vincent.guittot@linaro.org, daniel.lezcano@linaro.org, Dietmar Eggemann , yuyang.du@intel.com, rjw@rjwysocki.net, Juri Lelli , sgurrappadi@nvidia.com, pang.xunlei@zte.com.cn, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org Subject: Re: [RFCv5 PATCH 40/46] sched/cpufreq_sched: compute freq_new based on capacity_orig_of() Message-ID: <20150816202401.GJ10304@worktop.programming.kicks-ass.net> References: <1436293469-25707-1-git-send-email-morten.rasmussen@arm.com> <1436293469-25707-41-git-send-email-morten.rasmussen@arm.com> <20150815124638.GG10304@worktop.programming.kicks-ass.net> <20150816040333.31346.22542@quantum> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150816040333.31346.22542@quantum> User-Agent: Mutt/1.5.22.1 (2013-10-16) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1404 Lines: 29 On Sat, Aug 15, 2015 at 09:03:33PM -0700, Michael Turquette wrote: > Quoting Peter Zijlstra (2015-08-15 05:46:38) > > On Tue, Jul 07, 2015 at 07:24:23PM +0100, Morten Rasmussen wrote: > > > diff --git a/kernel/sched/cpufreq_sched.c b/kernel/sched/cpufreq_sched.c > > > index 2968f3a..7071528 100644 > > > --- a/kernel/sched/cpufreq_sched.c > > > +++ b/kernel/sched/cpufreq_sched.c > > > @@ -184,7 +184,7 @@ void cpufreq_sched_set_cap(int cpu, unsigned long capacity) > > > goto out; > > > > > > /* Convert the new maximum capacity request into a cpu frequency */ > > > - freq_new = capacity * policy->max >> SCHED_CAPACITY_SHIFT; > > > + freq_new = (capacity * policy->max) / capacity_orig_of(cpu); > > > > > > /* No change in frequency? Bail and return current capacity. */ > > > if (freq_new == policy->cur) > > > > Can't we avoid exporting that lot by simply passing in the right values > > to begin with? > > By "right value" do you mean, "pass the frequency from cfs"? Nah, just maybe: (capacity << SCHED_CAPACITY_SHIFT) / capacity_orig_of() such that you don't have to export that knowledge to this thing. -- 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/