| Message ID | 20210513171529.7977-1-bvanassche@acm.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | blk-mq: Swap two calls in blk_mq_exit_queue() | expand |
On Thu, May 13, 2021 at 10:15:29AM -0700, Bart Van Assche wrote: > If a tag set is shared across request queues (e.g. SCSI LUNs) then the > block layer core keeps track of the number of active request queues in > tags->active_queues. blk_mq_tag_busy() and blk_mq_tag_idle() update that > atomic counter if the hctx flag BLK_MQ_F_TAG_QUEUE_SHARED is set. Make > sure that blk_mq_exit_queue() calls blk_mq_tag_idle() before that flag is > cleared by blk_mq_del_queue_tag_set(). > > Cc: Christoph Hellwig <hch@infradead.org> > Cc: Ming Lei <ming.lei@redhat.com> > Cc: Hannes Reinecke <hare@suse.com> > Fixes: 0d2602ca30e4 ("blk-mq: improve support for shared tags maps") > Signed-off-by: Bart Van Assche <bvanassche@acm.org> > --- > block/blk-mq.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/block/blk-mq.c b/block/blk-mq.c > index 1ea012de60eb..96b8e3164835 100644 > --- a/block/blk-mq.c > +++ b/block/blk-mq.c > @@ -3289,10 +3289,12 @@ EXPORT_SYMBOL(blk_mq_init_allocated_queue); > /* tags can _not_ be used after returning from blk_mq_exit_queue */ > void blk_mq_exit_queue(struct request_queue *q) > { > - struct blk_mq_tag_set *set = q->tag_set; > + struct blk_mq_tag_set *set = q->tag_set; > > - blk_mq_del_queue_tag_set(q); > + /* Checks hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED. */ > blk_mq_exit_hw_queues(q, set, set->nr_hw_queues); > + /* May clear BLK_MQ_F_TAG_QUEUE_SHARED in hctx->flags. */ > + blk_mq_del_queue_tag_set(q); > } > > static int __blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) > Looks fine: Reviewed-by: Ming Lei <ming.lei@redhat.com>
On 5/13/21 11:15 AM, Bart Van Assche wrote: > If a tag set is shared across request queues (e.g. SCSI LUNs) then the > block layer core keeps track of the number of active request queues in > tags->active_queues. blk_mq_tag_busy() and blk_mq_tag_idle() update that > atomic counter if the hctx flag BLK_MQ_F_TAG_QUEUE_SHARED is set. Make > sure that blk_mq_exit_queue() calls blk_mq_tag_idle() before that flag is > cleared by blk_mq_del_queue_tag_set(). Applied, thanks.
diff --git a/block/blk-mq.c b/block/blk-mq.c index 1ea012de60eb..96b8e3164835 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3289,10 +3289,12 @@ EXPORT_SYMBOL(blk_mq_init_allocated_queue); /* tags can _not_ be used after returning from blk_mq_exit_queue */ void blk_mq_exit_queue(struct request_queue *q) { - struct blk_mq_tag_set *set = q->tag_set; + struct blk_mq_tag_set *set = q->tag_set; - blk_mq_del_queue_tag_set(q); + /* Checks hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED. */ blk_mq_exit_hw_queues(q, set, set->nr_hw_queues); + /* May clear BLK_MQ_F_TAG_QUEUE_SHARED in hctx->flags. */ + blk_mq_del_queue_tag_set(q); } static int __blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set)
If a tag set is shared across request queues (e.g. SCSI LUNs) then the block layer core keeps track of the number of active request queues in tags->active_queues. blk_mq_tag_busy() and blk_mq_tag_idle() update that atomic counter if the hctx flag BLK_MQ_F_TAG_QUEUE_SHARED is set. Make sure that blk_mq_exit_queue() calls blk_mq_tag_idle() before that flag is cleared by blk_mq_del_queue_tag_set(). Cc: Christoph Hellwig <hch@infradead.org> Cc: Ming Lei <ming.lei@redhat.com> Cc: Hannes Reinecke <hare@suse.com> Fixes: 0d2602ca30e4 ("blk-mq: improve support for shared tags maps") Signed-off-by: Bart Van Assche <bvanassche@acm.org> --- block/blk-mq.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)