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From: Jens Axboe <axboe@kernel.dk>
To: linux-block@vger.kernel.org, Ming Lei <ming.lei@redhat.com>
Cc: linux-kernel@vger.kernel.org, Tim Chen <tim.c.chen@linux.intel.com>, 
 Juri Lelli <juri.lelli@redhat.com>, Andrew Theurer <atheurer@redhat.com>, 
 Joe Mario <jmario@redhat.com>, Sebastian Jug <sejug@redhat.com>, 
 Frederic Weisbecker <frederic@kernel.org>, 
 Bart Van Assche <bvanassche@acm.org>, Tejun Heo <tj@kernel.org>
In-Reply-To: <20240322021244.1056223-1-ming.lei@redhat.com>
References: <20240322021244.1056223-1-ming.lei@redhat.com>
Subject: Re: [PATCH V5] blk-mq: don't schedule block kworker on isolated
 CPUs
Message-Id: <171155695404.507853.16905998627647073688.b4-ty@kernel.dk>
Date: Wed, 27 Mar 2024 10:29:14 -0600
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On Fri, 22 Mar 2024 10:12:44 +0800, Ming Lei wrote:
> Kernel parameter of `isolcpus=` or 'nohz_full=' are used to isolate CPUs
> for specific task, and it isn't expected to let block IO disturb these CPUs.
> blk-mq kworker shouldn't be scheduled on isolated CPUs. Also if isolated
> CPUs is run for blk-mq kworker, long block IO latency can be caused.
> 
> Kernel workqueue only respects CPU isolation for WQ_UNBOUND, for bound
> WQ, the responsibility is on user because CPU is specified as WQ API
> parameter, such as mod_delayed_work_on(cpu), queue_delayed_work_on(cpu)
> and queue_work_on(cpu).
> 
> [...]

Applied, thanks!

[1/1] blk-mq: don't schedule block kworker on isolated CPUs
      commit: 5f27f3d892743312fce237958a4194859ef93d69

Best regards,
-- 
Jens Axboe