[PATCH 04/16] md: add queue limit helpers

[Christoph Hellwig]

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.