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Date: Wed, 14 Oct 2026 09:34:04 -1000
Message-ID: <adebd7c36fe4c6e349aca65bd7820079@kernel.org>
From: Tejun Heo <tj@kernel.org>
To: Aaron Tomlin <atomlin@atomlin.com>
Cc: Ming Lei <tom.leiming@gmail.com>, axboe@kernel.dk, hare@suse.de,
 sean@ashe.io, neelx@suse.com, linux-block@vger.kernel.org,
 linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH] blk-mq: dispatch kworker to housekeeping CPU when hctx cpumask is empty
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Hello, Aaron.

On Mon, Oct 12, 2026 at 12:06:25PM -0400, Aaron Tomlin wrote:
> kblockd_workqueue is unique in that it is allocated as WQ_PERCPU to
> preserve per-CPU locality for multi-queue devices.

I haven't followed the earlier discussion, but if CPU locality is important
without requiring hard per-CPU affinity, an unbound workqueue with
non-strict "cpu" (or "smt" for core) affinity scope can provide both:
locality by default with flexibility to migrate when needed.

Thanks.

-- 
tejun