| Message ID | 20230822191822.337080-4-bvanassche@acm.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Improve write performance for zoned UFS devices | expand |
On 8/22/23 21:16, Bart Van Assche wrote: > Measurements have shown that limiting the queue depth to one per zone for > zoned writes has a significant negative performance impact on zoned UFS > devices. Hence this patch that disables zone locking by the mq-deadline > scheduler if the storage controller preserves the command order. This > patch is based on the following assumptions: > - It happens infrequently that zoned write requests are reordered by the > block layer. > - The I/O priority of all write requests is the same per zone. > - Either no I/O scheduler is used or an I/O scheduler is used that > serializes write requests per zone. > > Reviewed-by: Damien Le Moal <dlemoal@kernel.org> > Cc: Christoph Hellwig <hch@lst.de> > Cc: Ming Lei <ming.lei@redhat.com> > Signed-off-by: Bart Van Assche <bvanassche@acm.org> > --- > block/mq-deadline.c | 11 ++++++----- > 1 file changed, 6 insertions(+), 5 deletions(-) > Reviewed-by: Hannes Reinecke <hare@suse.de> Cheers, Hannes
On 23/08/22 12:16PM, Bart Van Assche wrote: >Measurements have shown that limiting the queue depth to one per zone for >zoned writes has a significant negative performance impact on zoned UFS >devices. Hence this patch that disables zone locking by the mq-deadline >scheduler if the storage controller preserves the command order. This >patch is based on the following assumptions: >- It happens infrequently that zoned write requests are reordered by the > block layer. >- The I/O priority of all write requests is the same per zone. >- Either no I/O scheduler is used or an I/O scheduler is used that > serializes write requests per zone. > >Reviewed-by: Damien Le Moal <dlemoal@kernel.org> >Cc: Christoph Hellwig <hch@lst.de> >Cc: Ming Lei <ming.lei@redhat.com> >Signed-off-by: Bart Van Assche <bvanassche@acm.org> >--- > block/mq-deadline.c | 11 ++++++----- > 1 file changed, 6 insertions(+), 5 deletions(-) > Reviewed-by: Nitesh Shetty <nj.shetty@samsung.com>
diff --git a/block/mq-deadline.c b/block/mq-deadline.c index f958e79277b8..082ccf3186f4 100644 --- a/block/mq-deadline.c +++ b/block/mq-deadline.c @@ -353,7 +353,7 @@ deadline_fifo_request(struct deadline_data *dd, struct dd_per_prio *per_prio, return NULL; rq = rq_entry_fifo(per_prio->fifo_list[data_dir].next); - if (data_dir == DD_READ || !blk_queue_is_zoned(rq->q)) + if (data_dir == DD_READ || !rq->q->limits.use_zone_write_lock) return rq; /* @@ -398,7 +398,7 @@ deadline_next_request(struct deadline_data *dd, struct dd_per_prio *per_prio, if (!rq) return NULL; - if (data_dir == DD_READ || !blk_queue_is_zoned(rq->q)) + if (data_dir == DD_READ || !rq->q->limits.use_zone_write_lock) return rq; /* @@ -526,8 +526,9 @@ static struct request *__dd_dispatch_request(struct deadline_data *dd, } /* - * For a zoned block device, if we only have writes queued and none of - * them can be dispatched, rq will be NULL. + * For a zoned block device that requires write serialization, if we + * only have writes queued and none of them can be dispatched, rq will + * be NULL. */ if (!rq) return NULL; @@ -934,7 +935,7 @@ static void dd_finish_request(struct request *rq) atomic_inc(&per_prio->stats.completed); - if (blk_queue_is_zoned(q)) { + if (rq->q->limits.use_zone_write_lock) { unsigned long flags; spin_lock_irqsave(&dd->zone_lock, flags);