Date: Fri, 22 Dec 2017 08:56:43 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Vincent Guittot <vincent.guittot@linaro.org>
Cc: 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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 <20171221102235.088181011@infradead.org>
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On Thu, Dec 21, 2017 at 05:23:27PM +0100, Vincent Guittot wrote:
> Hi Peter,
> 
> I think that part of the proposal is missing.
> 
> One goal of the patchset was to kick an update of the stats of idle
> cpu when a task wake up on a cpu but the statistic has not been
> updated for a while.
> 
> That's why there where a call to nohz_kick_needed in the proposal to
> kick ilb but only for updating blocked load and not a full idle load
> balance
> 
> I can't find this call any more in your patchset

Yeah, I took it out because it didn't make sense to me. If you're waking
to a stale CPU, you're too late.