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=-3.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 C5079CA9ECB for ; Thu, 31 Oct 2019 16:31:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8D2D620659 for ; Thu, 31 Oct 2019 16:31:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="jOt/U4mM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728593AbfJaQbz (ORCPT ); Thu, 31 Oct 2019 12:31:55 -0400 Received: from mail-lf1-f67.google.com ([209.85.167.67]:41453 "EHLO mail-lf1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726540AbfJaQbz (ORCPT ); Thu, 31 Oct 2019 12:31:55 -0400 Received: by mail-lf1-f67.google.com with SMTP id j14so5183835lfb.8 for ; Thu, 31 Oct 2019 09:31:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=QJy+/1CBSTIBM4kMR9zV2cJD7nIKgEp9xFX8JUKFW2E=; b=jOt/U4mMtKIUnd6iQExm2RnkfdpqCGqZsZ1DNnTOaUulO7dtPJ2YzxmzhKa+O+TCGn 00RC+P7bmfZ3WE65lTa8ej6+/5Jle55joSu8YwvzLEkjqhHErp6ELt48+Ne5gIau8wJO xPO+oHZsISV1M6oOSrc/2xRxCloRQEtAuOhPTAdkOrdv3QbVGO2CFcX37aPQGoos/wFY zGFj07ivqUJErado0/trG6eyVHsDPWPRMRnaeOC7JyzegJjl1CkST4UV2Wm7zNmrvBL1 AYeciSD2W2g3Ho68LJdYqlvXSuCZ5PeNEVpeQRirVQavIc+i+i29CvuNWxLWpKlImZcx Ogng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=QJy+/1CBSTIBM4kMR9zV2cJD7nIKgEp9xFX8JUKFW2E=; b=Mkh7GWlpc7EmI+EfDbOFfUBVPlrrtxa8OK6y4C/rutxp43OoZzVgmd2JQxzOkJcVGG p36Q8F7Il5Nh0yYk7D807024B9xdtul03dkEu/O4rp24awGTIMJd2bNg9wXuqtaDPhkU Nwdln34AwE4vSQemMBGtqGEVPNyVsRBzyCzhDt/SuKVrZkgrJ8ujNFk6MosHTq7Zwenb 8NpZjQnJaK8gwMRJwFNrlAsmz6HY0A+WfZQECkstUNqfi6LMj+EnWL5JuSk3fUBmvjt9 jZZ9Q79TPmLmbqEneF0/NMldDOdH3rPUlb/8/2xZtCJfEuLySn6VfrXc6cshsadhoHOe KubQ== X-Gm-Message-State: APjAAAUey9bhrenJ3Y3TTJ7/v84R+rp6C20fEqiCLL0Dslh88MqrvDCu xJFPChKzy+gXcxDJpoEwl9Fe3stLef+LCrbPyhAUlA== X-Google-Smtp-Source: APXvYqw8mOlWJ/N/hmIRPZrWSFfby917eKiZ41AwHu273ooh2iE0nJZSOupFUJHV/DFSo7bPrYDUKRRrlXIJSIvFE3w= X-Received: by 2002:a19:800a:: with SMTP id b10mr4231686lfd.15.1572539511165; Thu, 31 Oct 2019 09:31:51 -0700 (PDT) MIME-Version: 1.0 References: <1571776465-29763-1-git-send-email-thara.gopinath@linaro.org> <1571776465-29763-5-git-send-email-thara.gopinath@linaro.org> <20191023122252.dz7obopab6iizy4s@e107158-lin.cambridge.arm.com> <20191028153010.GE4097@hirez.programming.kicks-ass.net> <20191031105342.b3sl5xhysldfla3g@e107158-lin.cambridge.arm.com> In-Reply-To: From: Vincent Guittot Date: Thu, 31 Oct 2019 17:31:39 +0100 Message-ID: Subject: Re: [Patch v4 4/6] sched/fair: update cpu_capcity to reflect thermal pressure To: Dietmar Eggemann Cc: Qais Yousef , Peter Zijlstra , Thara Gopinath , Ingo Molnar , Ionela Voinescu , Zhang Rui , Eduardo Valentin , Quentin Perret , linux-kernel , Amit Kachhap , Javi Merino , Daniel Lezcano Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 31 Oct 2019 at 17:17, Dietmar Eggemann wrote: > > On 31.10.19 16:48, Vincent Guittot wrote: > > On Thu, 31 Oct 2019 at 16:38, Dietmar Eggemann wrote: > >> > >> On 31.10.19 11:53, Qais Yousef wrote: > >>> On 10/28/19 16:30, Peter Zijlstra wrote: > >>>> On Wed, Oct 23, 2019 at 01:28:40PM +0100, Qais Yousef wrote: > >>>>> On 10/22/19 16:34, Thara Gopinath wrote: > > [...] > > >>> To make sure I got this correctly - it's because avg_thermal.load_avg > >>> represents delta_capacity which is already a 'converted' form of load. So this > >>> makes avg_thermal.load_avg a util_avg really. Correct? > >>> > >>> If I managed to get it right somehow. It'd be nice if we can do inverse > >>> conversion on delta_capacity so that avg_thermal.{load_avg, util_avg} meaning > >>> is consistent across the board. But I don't feel strongly about it if this gets > >>> documented properly. > >> > >> So why can't we use rq->avg_thermal.util_avg here? Since capacity is > >> closer to util than to load? > >> > >> Is it because you want to use the influence of ___update_load_sum(..., > >> unsigned long load eq. per-cpu delta_capacity in your signal? > >> > >> Why not call it this way then? > > > > util_avg tracks a binary state with 2 fixed weights: running(1024) vs > > not running (0) > > In the case of thermal pressure, we want to track how much pressure is > > put on the CPU: capping to half the max frequency is not the same as > > capping only 10% > > load_avg is not boolean but you set the weight you want to apply and > > this weight reflects the amount of pressure. > > I see. This is what I meant by 'load (weight) eq. per-cpu delta_capacity > (pressure)'. > > > >> diff --git a/kernel/sched/pelt.c b/kernel/sched/pelt.c > >> index 38210691c615..d3035457483f 100644 > >> --- a/kernel/sched/pelt.c > >> +++ b/kernel/sched/pelt.c > >> @@ -357,9 +357,9 @@ int update_thermal_load_avg(u64 now, struct rq *rq, > >> u64 capacity) > >> { > >> if (___update_load_sum(now, &rq->avg_thermal, > >> capacity, > >> - capacity, > >> - capacity)) { > >> - ___update_load_avg(&rq->avg_thermal, 1, 1); > >> + 0, > >> + 0)) { > >> + ___update_load_avg(&rq->avg_thermal, 1, 0); > >> return 1; > >> } > > So we could call it this way since we don't care about runnable_load or > util? one way or the other is quite similar but the current solution is aligned with other irq, rt, dl signals which duplicates the same state in each fields