Subject: Re: [PATCH 6/8] cpufreq/schedutil: sum per-sched class utilization
To: Peter Zijlstra <peterz@infradead.org>,
        Michael Turquette <mturquette@baylibre.com>
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 <20160315212926.GG6344@twins.programming.kicks-ass.net>
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Cc: rjw@rjwysocki.net, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org,
        Juri.Lelli@arm.com, morten.rasmussen@arm.com, dietmar.eggemann@arm.com,
        vincent.guittot@linaro.org,
        Michael Turquette <mturquette+renesas@baylibre.com>
From: Steve Muckle <steve.muckle@linaro.org>
Message-ID: <56E9A3FD.9050309@linaro.org>
Date: Wed, 16 Mar 2016 11:20:45 -0700
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On 03/16/2016 12:38 AM, Peter Zijlstra wrote:
> Somewhere in the giant discussions I mentioned that we should be looking
> at a CPPC like interface and pass {min,max} tuples to the cpufreq
> selection thingy.
> 
> In that same discussion I also mentioned that we must compute min as the
> hard dl reservation, but that for max we can actually use the avg dl +
> avg rt + avg cfs.
> 
> That way there is far more room for selecting a sensible frequency.

Doesn't the above min/max policy mean that the platform will likely
underserve the task load? If avg dl+rt+cfs represents our best estimate
of the work to be done, I would think that should be the min.