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Date:   Tue, 17 Sep 2019 16:39:37 +0200
From:   Quentin Perret <qperret@qperret.net>
To:     Giovanni Gherdovich <ggherdovich@suse.cz>
Cc:     srinivas.pandruvada@linux.intel.com, tglx@linutronix.de,
        mingo@redhat.com, peterz@infradead.org, bp@suse.de,
        lenb@kernel.org, rjw@rjwysocki.net, x86@kernel.org,
        linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org,
        mgorman@techsingularity.net, matt@codeblueprint.co.uk,
        viresh.kumar@linaro.org, juri.lelli@redhat.com, pjt@google.com,
        vincent.guittot@linaro.org, dietmar.eggemann@arm.com
Subject: Re: [PATCH 1/2] x86,sched: Add support for frequency invariance
Message-ID: <20190917143937.GA334@qperret.net>
References: <20190909024216.5942-1-ggherdovich@suse.cz>
 <20190909024216.5942-2-ggherdovich@suse.cz>
 <20190914105708.GA12877@qperret.net>
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On Tuesday 17 Sep 2019 at 16:27:46 (+0200), Giovanni Gherdovich wrote:
> I'll check what's the cost of static_cpu_has() and if it's non-negligible I'll
> do what you suggest (x86-specific version of arch_scale_freq_invariant().

In case this is indeed expensive to check, you could always add a static
key, set at boot time, to optimize things a bit ... That might be worth
it since this is called in latency-sensitive paths of the scheduler.

Thanks,
Quentin