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Date:   Thu, 1 Feb 2018 17:55:57 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Morten Rasmussen <morten.rasmussen@foss.arm.com>
Cc:     Vincent Guittot <vincent.guittot@linaro.org>,
        Ingo Molnar <mingo@kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Brendan Jackman <brendan.jackman@arm.com>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Morten Rasmussen <morten.rasmussen@arm.com>
Subject: Re: [RFC PATCH 2/5] sched: Add NOHZ_STATS_KICK
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On Thu, Jan 18, 2018 at 10:38:07AM +0000, Morten Rasmussen wrote:
> It seems pointless to have a timer to update PELT if the system is
> completely idle, and when it isn't we can piggy back other events to
> make the updates happen.

Only if we do that update before making decisions based on the values.
The thing I was bothered by in the earlier patches was that wakeup would
use whatever current value and async kick something to go update.

That just seems wrong.