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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 75AAFC388F9 for ; Tue, 27 Oct 2020 11:11:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 24F3322258 for ; Tue, 27 Oct 2020 11:11:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2899033AbgJ0LLi (ORCPT ); Tue, 27 Oct 2020 07:11:38 -0400 Received: from foss.arm.com ([217.140.110.172]:38390 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2896957AbgJ0LLi (ORCPT ); Tue, 27 Oct 2020 07:11:38 -0400 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 9C9AB30E; Tue, 27 Oct 2020 04:11:37 -0700 (PDT) Received: from e107158-lin (e107158-lin.cambridge.arm.com [10.1.194.78]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 81D973F66E; Tue, 27 Oct 2020 04:11:35 -0700 (PDT) Date: Tue, 27 Oct 2020 11:11:33 +0000 From: Qais Yousef To: Peter Zijlstra Cc: "Rafael J. Wysocki" , Viresh Kumar , Julia Lawall , Mel Gorman , Ingo Molnar , kernel-janitors@vger.kernel.org, Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Daniel Bristot de Oliveira , linux-kernel@vger.kernel.org, Valentin Schneider , Gilles Muller , srinivas.pandruvada@linux.intel.com Subject: Re: default cpufreq gov, was: [PATCH] sched/fair: check for idle core Message-ID: <20201027111133.ajlxn5lbnfeocfgb@e107158-lin> References: <1603211879-1064-1-git-send-email-Julia.Lawall@inria.fr> <20201022071145.GM2628@hirez.programming.kicks-ass.net> <20201022104703.nw45dwor6wfn4ity@vireshk-i7> <34115486.YmRjPRKJaA@kreacher> <20201022120213.GG2611@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20201022120213.GG2611@hirez.programming.kicks-ass.net> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/22/20 14:02, Peter Zijlstra wrote: > On Thu, Oct 22, 2020 at 01:45:25PM +0200, Rafael J. Wysocki wrote: > > On Thursday, October 22, 2020 12:47:03 PM CEST Viresh Kumar wrote: > > > On 22-10-20, 09:11, Peter Zijlstra wrote: > > > > Well, but we need to do something to force people onto schedutil, > > > > otherwise we'll get more crap like this thread. > > > > > > > > Can we take the choice away? Only let Kconfig select which governors are > > > > available and then set the default ourselves? I mean, the end goal being > > > > to not have selectable governors at all, this seems like a good step > > > > anyway. > > > > > > Just to clarify and complete the point a bit here, the users can still > > > pass the default governor from cmdline using > > > cpufreq.default_governor=, which will take precedence over the one the > > > below code is playing with. And later once the kernel is up, they can > > > still choose a different governor from userspace. > > > > Right. > > > > Also some people simply set "performance" as the default governor and then > > don't touch cpufreq otherwise (the idea is to get everything to the max > > freq right away and stay in that mode forever). This still needs to be > > possible IMO. > > Performance/powersave make sense to keep. > > However I do want to retire ondemand, conservative and also very much > intel_pstate/active mode. I also have very little sympathy for > userspace. Userspace is useful for testing and sanity checking. Not sure if people use it to measure voltage/current at each frequency to generate dynamic-power-coefficient for their platform. Lukasz, Dietmar? Thanks -- Qais Yousef > > We should start by making it hard to use them and eventually just delete > them outright. >