Re: [PATCH] SCSI: run queue if SCSI device queue isn't ready and queue is idle

[Ming Lei]

On Tue, Dec 05, 2017 at 04:41:46PM +0000, Bart Van Assche wrote:
> On Wed, 2017-12-06 at 00:28 +0800, Ming Lei wrote:
> > This is still a workaround for RESTART, see my comment before:
> > 
> > 	https://marc.info/?l=linux-block&m=151217500929341&w=2
> 
> A quote from that e-mail: "The theory about using BLK_MQ_S_SCHED_RESTART in
> current way is that we mark it after requests are added to hctx->dispatch".
> Reading that makes me wonder whether you understand the purpose of the
> BLK_MQ_S_SCHED_RESTART flag? That flag is not set after requests are added
> to the dispatch list but after requests have been *removed*. The purpose of
> that flag is to detect whether another thread has run the queue after
> requests were removed from the dispatch list and before these were readded.
> If so, the queue needs to be rerun.

If you want to discuss that, please reply on that thread of '[PATCH 4/7] blk-mq:
Avoid that request processing sta', I will reply on you there too.

-- 
Ming