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 6F2D7C388F9 for ; Tue, 27 Oct 2020 11:42:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3260E22258 for ; Tue, 27 Oct 2020 11:42:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2899473AbgJ0LmV (ORCPT ); Tue, 27 Oct 2020 07:42:21 -0400 Received: from foss.arm.com ([217.140.110.172]:38990 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2899458AbgJ0LmU (ORCPT ); Tue, 27 Oct 2020 07:42:20 -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 7938D1FB; Tue, 27 Oct 2020 04:42:19 -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 634AE3F66E; Tue, 27 Oct 2020 04:42:17 -0700 (PDT) Date: Tue, 27 Oct 2020 11:42:14 +0000 From: Qais Yousef To: Valentin Schneider Cc: Peter Zijlstra , "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, Gilles Muller , srinivas.pandruvada@linux.intel.com Subject: Re: default cpufreq gov, was: [PATCH] sched/fair: check for idle core Message-ID: <20201027114214.irsgdlfvyo46jpww@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> <20201027111133.ajlxn5lbnfeocfgb@e107158-lin> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/27/20 11:26, Valentin Schneider wrote: > > On 27/10/20 11:11, Qais Yousef wrote: > > On 10/22/20 14:02, Peter Zijlstra wrote: > >> 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? > > > > It's valuable even just for cpufreq sanity checking - we have that test > that goes through increasing frequencies and asserts the work done is > monotonically increasing. This has been quite useful in the past to detect > broken bits. > > That *should* still be totally doable with any other governor by using the > scaling_{min, max}_freq sysfs interface. True. This effectively makes every governor a potential user space governor. /me not sure to be happy or grumpy about it Thanks -- Qais Yousef