| Message ID | 20180228173529.24941-1-bart.vanassche@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Feb 28, 2018 at 09:35:29AM -0800, Bart Van Assche wrote: > From: Damien Le Moal <damien.lemoal@wdc.com> > > In case of a failed write request (all retries failed) and when using > libata, the SCSI error handler calls scsi_finish_command(). In the > case of blk-mq this means that scsi_mq_done() does not get called, > that blk_mq_complete_request() does not get called and also that the > mq-deadline .completed_request() method is not called. This results in > the target zone of the failed write request being left in a locked > state, preventing that any new write requests are issued to the same > zone. > > Fix this by replacing the .completed_request() method with the > .finish_request() method as this method is always called whether or > not a request completes successfully. Since the .finish_request() > method is only called by the blk-mq core if a .prepare_request() > method exists, add a dummy .prepare_request() method. > > Fixes: 5700f69178e9 ("mq-deadline: Introduce zone locking support") > Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> > Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> > [ bvanassche: edited patch description ] > Cc: Hannes Reinecke <hare@suse.com> > Cc: Ming Lei <ming.lei@redhat.com> > --- > block/mq-deadline.c | 16 +++++++++++++--- > 1 file changed, 13 insertions(+), 3 deletions(-) > > diff --git a/block/mq-deadline.c b/block/mq-deadline.c > index c56f211c8440..8ec0ba9f5386 100644 > --- a/block/mq-deadline.c > +++ b/block/mq-deadline.c > @@ -535,13 +535,22 @@ static void dd_insert_requests(struct blk_mq_hw_ctx *hctx, > spin_unlock(&dd->lock); > } > > +/* > + * Nothing to do here. This is defined only to ensure that .finish_request > + * method is called upon request completion. > + */ > +static void dd_prepare_request(struct request *rq, struct bio *bio) > +{ > +} > + > /* > * For zoned block devices, write unlock the target zone of > * completed write requests. Do this while holding the zone lock > * spinlock so that the zone is never unlocked while deadline_fifo_request() > - * while deadline_next_request() are executing. > + * or deadline_next_request() are executing. This function is called for > + * all requests, whether or not these requests complete successfully. > */ > -static void dd_completed_request(struct request *rq) > +static void dd_finish_request(struct request *rq) > { > struct request_queue *q = rq->q; > > @@ -756,7 +765,8 @@ static struct elevator_type mq_deadline = { > .ops.mq = { > .insert_requests = dd_insert_requests, > .dispatch_request = dd_dispatch_request, > - .completed_request = dd_completed_request, > + .prepare_request = dd_prepare_request, > + .finish_request = dd_finish_request, > .next_request = elv_rb_latter_request, > .former_request = elv_rb_former_request, > .bio_merge = dd_bio_merge, > -- > 2.16.2 > Looks fine: Reviewed-by: Ming Lei <ming.lei@redhat.com> Thanks, Ming
On 2/28/18 10:35 AM, Bart Van Assche wrote: > From: Damien Le Moal <damien.lemoal@wdc.com> > > In case of a failed write request (all retries failed) and when using > libata, the SCSI error handler calls scsi_finish_command(). In the > case of blk-mq this means that scsi_mq_done() does not get called, > that blk_mq_complete_request() does not get called and also that the > mq-deadline .completed_request() method is not called. This results in > the target zone of the failed write request being left in a locked > state, preventing that any new write requests are issued to the same > zone. > > Fix this by replacing the .completed_request() method with the > .finish_request() method as this method is always called whether or > not a request completes successfully. Since the .finish_request() > method is only called by the blk-mq core if a .prepare_request() > method exists, add a dummy .prepare_request() method. Thanks, applied for 4.16.
diff --git a/block/mq-deadline.c b/block/mq-deadline.c index c56f211c8440..8ec0ba9f5386 100644 --- a/block/mq-deadline.c +++ b/block/mq-deadline.c @@ -535,13 +535,22 @@ static void dd_insert_requests(struct blk_mq_hw_ctx *hctx, spin_unlock(&dd->lock); } +/* + * Nothing to do here. This is defined only to ensure that .finish_request + * method is called upon request completion. + */ +static void dd_prepare_request(struct request *rq, struct bio *bio) +{ +} + /* * For zoned block devices, write unlock the target zone of * completed write requests. Do this while holding the zone lock * spinlock so that the zone is never unlocked while deadline_fifo_request() - * while deadline_next_request() are executing. + * or deadline_next_request() are executing. This function is called for + * all requests, whether or not these requests complete successfully. */ -static void dd_completed_request(struct request *rq) +static void dd_finish_request(struct request *rq) { struct request_queue *q = rq->q; @@ -756,7 +765,8 @@ static struct elevator_type mq_deadline = { .ops.mq = { .insert_requests = dd_insert_requests, .dispatch_request = dd_dispatch_request, - .completed_request = dd_completed_request, + .prepare_request = dd_prepare_request, + .finish_request = dd_finish_request, .next_request = elv_rb_latter_request, .former_request = elv_rb_former_request, .bio_merge = dd_bio_merge,