Re: [PATCH] blk: do rq_qos_exit in blk_cleanup_queue

From: Christoph Hellwig
Date: Thu Feb 17 2022 - 10:48:43 EST


On Thu, Feb 17, 2022 at 07:55:16AM -0700, Jens Axboe wrote:
> > from Jan 22. Although it would need a rebase so it can be applied
> > without the preceding patches.
>
> Can someone respin that for 5.17 then?

I looked at it and it I don't think we can do that without a lot of
the prep patches.

That being said I think this version of the patch also is buggy, we
want the policies shut down in del_gendisk with the queue frozen for
normal operation.

I guess until we can move the initialization and teardown entirely
to the gendisk as in Ming's more complex series we need to keep the
call in del_gendisk and also do it in blk_cleanup_queue. For the
normal shutdown on disk that were life del_gendisk does the all the
work on the frozen queue, while for queues that never had a disk
blk_cleanup_queue will clean up the unused rq_qos.