linux-kernel - Re: [patch V3 08/20] sched/mmcid: Use cpumask_weighted

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Message-ID: <4b807c64-92b6-4604-a277-68d9b1bf972b@efficios.com>
Date: Wed, 29 Oct 2025 11:51:04 -0400
From: Mathieu Desnoyers <mathieu.desnoyers@...icios.com>
To: Thomas Gleixner <tglx@...utronix.de>, LKML <linux-kernel@...r.kernel.org>
Cc: Peter Zijlstra <peterz@...radead.org>,
 Gabriele Monaco <gmonaco@...hat.com>, Michael Jeanson
 <mjeanson@...icios.com>, Jens Axboe <axboe@...nel.dk>,
 "Paul E. McKenney" <paulmck@...nel.org>,
 "Gautham R. Shenoy" <gautham.shenoy@....com>,
 Florian Weimer <fweimer@...hat.com>, Tim Chen <tim.c.chen@...el.com>,
 Yury Norov <yury.norov@...il.com>, Shrikanth Hegde <sshegde@...ux.ibm.com>
Subject: Re: [patch V3 08/20] sched/mmcid: Use cpumask_weighted_or()

On 2025-10-29 09:09, Thomas Gleixner wrote:
> Use cpumask_weighted_or() instead of cpumask_or() and cpumask_weight() on
> the result, which walks the same bitmap twice. Results in 10-20% less
> cycles, which reduces the runqueue lock hold time.
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@...icios.com>

-- 
Mathieu Desnoyers
EfficiOS Inc.
https://www.efficios.com