From mboxrd@z Thu Jan 1 00:00:00 1970 From: Qais Yousef Date: Tue, 27 Oct 2020 11:42:14 +0000 Subject: Re: default cpufreq gov, was: [PATCH] sched/fair: check for idle core Message-Id: <20201027114214.irsgdlfvyo46jpww@e107158-lin> List-Id: 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> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit 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 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