[PATCH v5 03/14] blk-mq: Relocate shared sbitmap resize in blk_mq_update_nr_requests()
From: John Garry <hidden>
Date: 2021-10-05 10:29:04
Also in:
linux-block, lkml
Subsystem:
block layer, the rest · Maintainers:
Jens Axboe, Linus Torvalds
For shared sbitmap, if the call to blk_mq_tag_update_depth() was successful for any hctx when hctx->sched_tags is not set, then it would be successful for all (due to nature in which blk_mq_tag_update_depth() fails). As such, there is no need to call blk_mq_tag_resize_shared_sbitmap() for each hctx. So relocate the call until after the hctx iteration under the !q->elevator check, which is equivalent (to !hctx->sched_tags). Signed-off-by: John Garry <redacted> Reviewed-by: Ming Lei <redacted> Reviewed-by: Hannes Reinecke <hare@suse.de> --- block/blk-mq.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index bc8238ab1aef..290821580ecf 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c@@ -3618,8 +3618,6 @@ int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) if (!hctx->sched_tags) { ret = blk_mq_tag_update_depth(hctx, &hctx->tags, nr, false); - if (!ret && blk_mq_is_sbitmap_shared(set->flags)) - blk_mq_tag_resize_shared_sbitmap(set, nr); } else { ret = blk_mq_tag_update_depth(hctx, &hctx->sched_tags, nr, true);
@@ -3637,9 +3635,13 @@ int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr) } if (!ret) { q->nr_requests = nr; - if (q->elevator && blk_mq_is_sbitmap_shared(set->flags)) - sbitmap_queue_resize(&q->sched_bitmap_tags, - nr - set->reserved_tags); + if (blk_mq_is_sbitmap_shared(set->flags)) { + if (q->elevator) + sbitmap_queue_resize(&q->sched_bitmap_tags, + nr - set->reserved_tags); + else + blk_mq_tag_resize_shared_sbitmap(set, nr); + } } blk_mq_unquiesce_queue(q);
--
2.26.2