blk-mq: don't run might_sleep() if the operation needn't blocking
The operation protected via blk_mq_run_dispatch_ops() in blk_mq_run_hw_queue
won't sleep, so don't run might_sleep() for it.
Reported-and-tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/block/blk-mq.h b/block/blk-mq.h
index d62004e..948791e 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -375,7 +375,7 @@ static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx,
}
/* run the code block in @dispatch_ops with rcu/srcu read lock held */
-#define blk_mq_run_dispatch_ops(q, dispatch_ops) \
+#define __blk_mq_run_dispatch_ops(q, check_sleep, dispatch_ops) \
do { \
if (!blk_queue_has_srcu(q)) { \
rcu_read_lock(); \
@@ -384,11 +384,14 @@ do { \
} else { \
int srcu_idx; \
\
- might_sleep(); \
+ might_sleep_if(check_sleep); \
srcu_idx = srcu_read_lock((q)->srcu); \
(dispatch_ops); \
srcu_read_unlock((q)->srcu, srcu_idx); \
} \
} while (0)
+#define blk_mq_run_dispatch_ops(q, dispatch_ops) \
+ __blk_mq_run_dispatch_ops(q, true, dispatch_ops) \
+
#endif