[PATCH v2] blk-mq: Fix blk_mq_tagset_busy_iter() for shared tags
From: John Garry <hidden>
Date: 2021-10-18 09:46:59
Also in:
lkml
Subsystem:
block layer, the rest · Maintainers:
Jens Axboe, Linus Torvalds
Since it is now possible for a tagset to share a single set of tags, the
iter function should not re-iter the tags for the count of #hw queues in
that case. Rather it should just iter once.
Fixes: e0fdf846c7bb ("blk-mq: Use shared tags for shared sbitmap support")
Reported-by: Kashyap Desai <kashyap.desai@broadcom.com>
Signed-off-by: John Garry <redacted>
Reviewed-by: Ming Lei <redacted>
---
Diff to v1:
- Add Ming's RB tag
diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index 72a2724a4eee..c943b6529619 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c@@ -378,9 +378,12 @@ void blk_mq_all_tag_iter(struct blk_mq_tags *tags, busy_tag_iter_fn *fn, void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset, busy_tag_iter_fn *fn, void *priv) { - int i; + unsigned int flags = tagset->flags; + int i, nr_tags; + + nr_tags = blk_mq_is_shared_tags(flags) ? 1 : tagset->nr_hw_queues; - for (i = 0; i < tagset->nr_hw_queues; i++) { + for (i = 0; i < nr_tags; i++) { if (tagset->tags && tagset->tags[i]) __blk_mq_all_tag_iter(tagset->tags[i], fn, priv, BT_TAG_ITER_STARTED);
--
2.26.2