This is in preparation for a fix, but serves as a cleanup as well moving
the plugged request logic out of blk_mq_submit_bio().
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
block/blk-mq.c | 23 +++++++++++++++++++----
1 file changed, 19 insertions(+), 4 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 5498454c2164..f7f36d5ed25a 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2478,6 +2478,23 @@ static inline unsigned short blk_plug_max_rq_count(struct blk_plug *plug)
return BLK_MAX_REQUEST_COUNT;
}
+static inline struct request *blk_get_plug_request(struct request_queue *q,
+ struct blk_plug *plug,
+ struct bio *bio)
+{
+ struct request *rq;
+
+ if (!plug)
+ return NULL;
+ rq = rq_list_peek(&plug->cached_rq);
+ if (rq) {
+ plug->cached_rq = rq_list_next(rq);
+ INIT_LIST_HEAD(&rq->queuelist);
+ return rq;
+ }
+ return NULL;
+}
+
/**
* blk_mq_submit_bio - Create and send a request to block device.
* @bio: Bio pointer.
@@ -2518,10 +2535,8 @@ void blk_mq_submit_bio(struct bio *bio)
rq_qos_throttle(q, bio);
plug = blk_mq_plug(q, bio);
- if (plug && plug->cached_rq) {
- rq = rq_list_pop(&plug->cached_rq);
- INIT_LIST_HEAD(&rq->queuelist);
- } else {
+ rq = blk_get_plug_request(q, plug, bio);
+ if (!rq) {
struct blk_mq_alloc_data data = {
.q = q,
.nr_tags = 1,
--
2.33.1
