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From: Vincent Guittot <vincent.guittot@linaro.org>
Date: Fri, 22 Dec 2017 09:05:45 +0100
Message-ID: <CAKfTPtC0+5zjvgNXMyVcvnnyJh0giQgJHtx+5p-GEpjUW1x8eg@mail.gmail.com>
Subject: Re: [RFC PATCH 2/5] sched: Add NOHZ_STATS_KICK
To: Peter Zijlstra <peterz@infradead.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>
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On 22 December 2017 at 08:59, Peter Zijlstra <peterz@infradead.org> wrote:
> On Thu, Dec 21, 2017 at 05:56:32PM +0100, Vincent Guittot wrote:
>> In fact, we can't only rely on the tick and newly_idle load balance to
>> ensure a period update of the blocked load because they can never
>> happen.
>
> I'm confused, why would the ilb not happen?

the ilb will be kick only if tick fires which might not be the case
for task that runs less than a tick