On 11/29/18 8:45 AM, Christoph Hellwig wrote: > On Wed, Nov 28, 2018 at 06:35:33AM -0700, Jens Axboe wrote: >> blk-mq passes information to the hardware about any given request being >> the last that we will issue in this sequence. The point is that hardware >> can defer costly doorbell type writes to the last request. But if we run >> into errors issuing a sequence of requests, we may never send the request >> with bd->last == true set. For that case, we need a hook that tells the >> hardware that nothing else is coming right now. >> >> For failures returned by the drivers ->queue_rq() hook, the driver is >> responsible for flushing pending requests, if it uses bd->last to >> optimize that part. This works like before, no changes there. >> >> Reviewed-by: Omar Sandoval <osandov@xxxxxx> >> Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx> >> Reviewed-by: Christoph Hellwig <hch@xxxxxx> > > I don't think I actually reviewed it before in this form. > > But now that I took a look it does indeed look fine to me: > > Reviewed-by: Christoph Hellwig <hch@xxxxxx> Only change is moving those two hunks from the later patch into this one, so it isn't an empty declaration. -- Jens Axboe
