block: pass no-op callback to INIT_WORK().

[mirror_ubuntu-bionic-kernel.git] / block / blk-mq-sched.c

diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
index c117bd8fd1f6126849472300b3c294e65825a2f7..fc64558241c90eb636866b744421514f4d5af8f7 100644 (file)
--- a/block/blk-mq-sched.c
+++ b/block/blk-mq-sched.c
@@ -324,7 +324,8 @@ bool __blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio)
                return e->type->ops.mq.bio_merge(hctx, bio);
        }
 
-       if (hctx->flags & BLK_MQ_F_SHOULD_MERGE) {
+       if ((hctx->flags & BLK_MQ_F_SHOULD_MERGE) &&
+                       !list_empty_careful(&ctx->rq_list)) {
                /* default per sw-queue merge */
                spin_lock(&ctx->lock);
                ret = blk_mq_attempt_merge(q, ctx, bio);