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Date: Tue, 27 Feb 2024 15:36:18 +0100
From: Christoph Hellwig <hch@lst.de>
To: Yu Kuai <yukuai1@huaweicloud.com>
Subject: Re: [PATCH 04/16] md: add queue limit helpers
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Cc: Jens Axboe <axboe@kernel.dk>, dm-devel@lists.linux.dev,
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On Mon, Feb 26, 2024 at 07:38:17PM +0800, Yu Kuai wrote:
> Any reason to use blk_mq_freeze/unfreeze_queue ? I don't think this is
> meaningful for raid, this only wait for IO submission, not IO done.
>
> raid should already handle concurrent IO with reshape, so I think this
> can just be removed.

We can't just change limits under the driver if I/Os are being sumitted.
That is one of the points of the whole queue limits exercises.