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Subject: Re: [PATCH] sched/fair: Fix task utilization accountability in
 cpu_util_next()
To:     vincent.donnefort@arm.com, peterz@infradead.org, mingo@redhat.com,
        vincent.guittot@linaro.org
Cc:     linux-kernel@vger.kernel.org, qperret@google.com,
        patrick.bellasi@matbug.net, valentin.schneider@arm.com
References: <20210222095401.37158-1-vincent.donnefort@arm.com>
From:   Dietmar Eggemann <dietmar.eggemann@arm.com>
Message-ID: <66a16cf1-ffc5-2a40-7e04-900cc0e2ee2c@arm.com>
Date:   Tue, 23 Feb 2021 15:44:41 +0100
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On 22/02/2021 10:54, vincent.donnefort@arm.com wrote:
> From: Vincent Donnefort <vincent.donnefort@arm.com>

[...]

> Also, replace sub_positive with lsub_positive which saves one explicit
> load-store.

IMHO, in case you're going to fix this now in compute_energy(), this
optimization could still be done. Maybe in an extra patch?
cpu_util_without() is using lsub_positive() to remove task util from cpu
util as well.

[...]