This reverts commit 23f3e3272e7a4d9fb870485cd6df1e4f9539282c.
blk-mq sched bio merge still needs request to grab queue usage counter,
so we can't simply call blk_mq_attempt_bio_merge() when queue usage
counter isn't held.
Fixes: 23f3e3272e7a ("block: Merge bio before checking ->cached_rq")
Cc: Xiao Ni <xni@xxxxxxxxxx>
Reported-by: Yi Zhang <yi.zhang@xxxxxxxxxx>
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
block/blk-mq.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index cf1a39adf9a5..27a628a8ee88 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2880,16 +2880,15 @@ static inline struct request *blk_mq_get_cached_request(struct request_queue *q,
if (!plug)
return NULL;
+ rq = rq_list_peek(&plug->cached_rq);
+ if (!rq || rq->q != q)
+ return NULL;
if (blk_mq_attempt_bio_merge(q, *bio, nsegs)) {
*bio = NULL;
return NULL;
}
- rq = rq_list_peek(&plug->cached_rq);
- if (!rq || rq->q != q)
- return NULL;
-
type = blk_mq_get_hctx_type((*bio)->bi_opf);
hctx_type = rq->mq_hctx->type;
if (type != hctx_type &&
--
2.39.2
