From: Ming Lei <ming.lei@redhat.com>
Date: Mon, 6 Dec 2021 19:12:13 +0800
Subject: [PATCH] blk-mq: don't run might_sleep() if the operation needn't
blocking
Git-commit: 41adf531e390e7969f00a560b8971cbf42f5a6da
Patch-mainline: v5.17-rc1
References: jsc#PED-1183
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>
Acked-by: Hannes Reinecke <hare@suse.com>
---
block/blk-mq.c | 2 +-
block/blk-mq.h | 7 +++++--
2 files changed, 6 insertions(+), 3 deletions(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 22ec21aa0c22..706e9a836fe6 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2048,7 +2048,7 @@ void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async)
* And queue will be rerun in blk_mq_unquiesce_queue() if it is
* quiesced.
*/
- blk_mq_run_dispatch_ops(hctx->queue,
+ __blk_mq_run_dispatch_ops(hctx->queue, false,
need_run = !blk_queue_quiesced(hctx->queue) &&
blk_mq_hctx_has_pending(hctx));
diff --git a/block/blk-mq.h b/block/blk-mq.h
index d62004e2d531..948791ea2a3e 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
--
2.35.3