From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4CB21C5DF63 for ; Wed, 6 Nov 2019 16:56:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 237CB2173E for ; Wed, 6 Nov 2019 16:56:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732325AbfKFQ4x (ORCPT ); Wed, 6 Nov 2019 11:56:53 -0500 Received: from foss.arm.com ([217.140.110.172]:43158 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732201AbfKFQ4w (ORCPT ); Wed, 6 Nov 2019 11:56:52 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 375C746A; Wed, 6 Nov 2019 08:56:52 -0800 (PST) Received: from e107158-lin.cambridge.arm.com (e107158-lin.cambridge.arm.com [10.1.195.21]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 9CC9B3F719; Wed, 6 Nov 2019 08:56:50 -0800 (PST) Date: Wed, 6 Nov 2019 16:56:48 +0000 From: Qais Yousef To: Thara Gopinath Cc: mingo@redhat.com, peterz@infradead.org, ionela.voinescu@arm.com, vincent.guittot@linaro.org, rui.zhang@intel.com, edubezval@gmail.com, qperret@google.com, linux-kernel@vger.kernel.org, amit.kachhap@gmail.com, javi.merino@kernel.org, daniel.lezcano@linaro.org Subject: Re: [Patch v5 4/6] sched/fair: update cpu_capcity to reflect thermal pressure Message-ID: <20191106165646.vc7j4hbhj2hcrku4@e107158-lin.cambridge.arm.com> References: <1572979786-20361-1-git-send-email-thara.gopinath@linaro.org> <1572979786-20361-5-git-send-email-thara.gopinath@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1572979786-20361-5-git-send-email-thara.gopinath@linaro.org> User-Agent: NeoMutt/20171215 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/05/19 13:49, Thara Gopinath wrote: > cpu_capacity relflects the maximum available capacity of a cpu. Thermal > pressure on a cpu means this maximum available capacity is reduced. This > patch reduces the average thermal pressure for a cpu from its maximum > available capacity so that cpu_capacity reflects the actual > available capacity. > > Other signals that are deducted from cpu_capacity to reflect the actual > capacity available are rt and dl util_avg. util_avg tracks a binary signal > and uses the weights 1024 and 0. Whereas thermal pressure is tracked > using load_avg. load_avg uses the actual "delta" capacity as the weight. I think you intended to put this as comment... > > Signed-off-by: Thara Gopinath > --- > kernel/sched/fair.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index 9fb0494..5f6c371 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -7738,6 +7738,7 @@ static unsigned long scale_rt_capacity(struct sched_domain *sd, int cpu) > > used = READ_ONCE(rq->avg_rt.util_avg); > used += READ_ONCE(rq->avg_dl.util_avg); > + used += READ_ONCE(rq->avg_thermal.load_avg); ... here? I find the explanation hard to parse too. Do you think you can rephrase it? Something based on what you wrote here would be more understandable IMHO: https://lore.kernel.org/lkml/5DBB05BC.40502@linaro.org/ Thanks! -- Qais Yousef > > if (unlikely(used >= max)) > return 1; > -- > 2.1.4 >