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Subject: Re: [PATCH 3/9] sched/hotplug: Ensure only per-cpu kthreads run
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To:     Peter Zijlstra <peterz@infradead.org>, tglx@linutronix.de,
        mingo@kernel.org
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        qais.yousef@arm.com, swood@redhat.com, valentin.schneider@arm.com,
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        bristot@redhat.com, vincent.donnefort@arm.com
References: <20200921163557.234036895@infradead.org>
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From:   Dietmar Eggemann <dietmar.eggemann@arm.com>
Message-ID: <b357302d-4a8c-aa2e-f31d-4501fce890b6@arm.com>
Date:   Fri, 25 Sep 2020 18:38:50 +0200
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On 21/09/2020 18:36, Peter Zijlstra wrote:

[...]

> This replaces the unlikely(rq->balance_callbacks) test at the tail of
> context_switch with an unlikely(rq->balance_work), the fast path is

While looking for why BALANCE_WORK is needed:

Shouldn't this be unlikely(rq->balance_callback) and
unlikely(rq->balance_flags)?