Re: [PATCH 4/4] block: cancel all throttled bios in blk_cleanup_queue()

[Christoph Hellwig]

On Wed, Sep 22, 2021 at 08:51:15PM +0800, Yu Kuai wrote:
> Throttled bios can't be issued after queue is dying in
> blk_cleanup_queue(), thus it's better to cancel them immediately
> rather than waiting for throttle is done.
> 
> For example, if user thread is throttled with low bps while is
> issuing large io, and the device is deleted. The user thread will
> wait for a long time for io to return.

blk_cleanup_queue is too late, this will need to go into del_gendisk
and on top of my "tear down file system I/O in del_gendisk" series.