Date: Thu, 3 Mar 2016 17:56:40 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Juri Lelli <juri.lelli@arm.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>,
        Linux PM list <linux-pm@vger.kernel.org>,
        Steve Muckle <steve.muckle@linaro.org>,
        ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
        Viresh Kumar <viresh.kumar@linaro.org>,
        Michael Turquette <mturquette@baylibre.com>
Subject: Re: [PATCH 6/6] cpufreq: schedutil: New governor based on scheduler
 utilization data
Message-ID: <20160303165640.GT6356@twins.programming.kicks-ass.net>
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On Thu, Mar 03, 2016 at 04:55:44PM +0000, Juri Lelli wrote:
> On 03/03/16 17:37, Peter Zijlstra wrote:
> > But given the platform's cpuidle information, maybe coupled with an avg
> > idle est, we can compute the benefit of race-to-idle and over provision
> > based on that, right?
> > 
> 
> Shouldn't this kind of considerations be a scheduler thing? I'm not
> really getting why we want to put more "intelligence" in a new governor.
> Also, if I understand Ingo's point correctly, I think we want to make
> this kind of policy decisions inside the scheduler.

Well sure, put it in kernel/sched/cpufreq.c or wherever. My point was
more that we don't have to guess/hardcode race-to-idle assumptions but
can actually calculate some of that.