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Subject: Re: [PATCH] sched/fair: Rearrange select_task_rq_fair() to optimize
 it
To: Peter Zijlstra <peterz@infradead.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>, Ingo Molnar <mingo@redhat.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        linux-kernel@vger.kernel.org, Quentin Perret <quentin.perret@arm.com>
References: <8a34a16da90b9f83ffe60316a074a5e4d05b59b0.1524479666.git.viresh.kumar@linaro.org>
 <434fa179-7c8f-8a01-a07a-4527521a04c7@arm.com>
 <20180424104304.GE4064@hirez.programming.kicks-ass.net>
From: Valentin Schneider <valentin.schneider@arm.com>
Message-ID: <0985e709-0d71-2c08-20a9-7bfb618fb5f2@arm.com>
Date: Tue, 24 Apr 2018 12:19:07 +0100
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On 24/04/18 11:43, Peter Zijlstra wrote:
> On Tue, Apr 24, 2018 at 11:02:26AM +0100, Valentin Schneider wrote:
>> I'd argue making things easier to read is a non-negligible part as well.
> 
> Right, so I don't object to either of these (I think); but it would be
> good to see this in combination with that proposed EAS change.
> 

True, I would've said the call to find_energy_efficient_cpu() ([1]) could
simply be added to the if (sd) {} case, but...

> I think you (valentin) wanted to side-step the entire domain loop in
> that case or something.
> 

...this would change more things. Admittedly I've been sort of out of the loop
(no pun intended) lately, but this doesn't ring a bell. That might have been
the other frenchie (Quentin) :)

> But yes, getting this code more readable is defninitely useful.
> 

[1]: See [RFC PATCH v2 5/6] sched/fair: Select an energy-efficient CPU on task wake-up
@ https://lkml.org/lkml/2018/4/6/856