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Date: Tue, 13 Sep 2016 09:34:39 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Linux PM list <linux-pm@vger.kernel.org>,
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        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Steve Muckle <smuckle@linaro.org>,
        Doug Smythies <doug.smythies@gmail.com>
Subject: Re: [Resend][PATCH 1/3] cpufreq / sched: SCHED_CPUFREQ_IOWAIT flag
 to indicate iowait condition
Message-ID: <20160913073439.GD5008@twins.programming.kicks-ass.net>
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On Fri, Sep 09, 2016 at 11:59:33PM +0200, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> 
> Testing indicates that it is possible to improve performace
> significantly without increasing energy consumption too much by
> teaching cpufreq governors to bump up the CPU performance level if
> the in_iowait flag is set for the task in enqueue_task_fair().
> 
> For this purpose, define a new cpufreq_update_util() flag
> SCHED_CPUFREQ_IOWAIT and modify enqueue_task_fair() to pass that
> flag to cpufreq_update_util() in the in_iowait case.  That generally
> requires cpufreq_update_util() to be called directly from there,
> because update_load_avg() may not be invoked in that case.
> 
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> Looks-good-to: Steve Muckle <smuckle@linaro.org>

Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>