Re: [PATCH 1/6] xen-blkfront: avoid to use start/stop queue

Ming Lei
2017-07-12T03:12:23Z

On Tue, Jul 11, 2017 at 11:24:44PM +0200, Roger Pau Monnï¿½ wrote:
> On Wed, Jul 12, 2017 at 02:20:58AM +0800, Ming Lei wrote:
> > This interfaces will be removed soon, so use quiesce and
> > unquiesce instead, which should be more safe.
> >
> > The only one usage will be removed in the following
> > congestion control patches.
>
> Would it be better to simply fix blk_mq_{start/stop}_stopped_hw_queues
> rather than introducing a new interface?

No, we do not want to expose start/stop state to drivers any more, which
has caused enough trouble already, so these APIs need to be removed, and
quiesce/unquiesce is preferred way for this purpose, as you can see
the work done by Sagi Grimberg:

http://marc.info/?t=149927415900006&r=1&w=2

Thanks,
Ming