diff options
| author | Ming Lei <ming.lei@redhat.com> | 2020-06-19 11:42:14 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-08-21 10:48:20 +0300 |
| commit | b0a52e5dbb0e731d4b069eacab91d737201a90f2 (patch) | |
| tree | 5949cf2606d8d5926dc868bcd9f7ab55c838431e /drivers | |
| parent | 24e014e194b66d5535163e3efc25da650a0120d8 (diff) | |
| download | linux-b0a52e5dbb0e731d4b069eacab91d737201a90f2.tar.xz | |
dm rq: don't call blk_mq_queue_stopped() in dm_stop_queue()
[ Upstream commit e766668c6cd49d741cfb49eaeb38998ba34d27bc ]
dm_stop_queue() only uses blk_mq_quiesce_queue() so it doesn't
formally stop the blk-mq queue; therefore there is no point making the
blk_mq_queue_stopped() check -- it will never be stopped.
In addition, even though dm_stop_queue() actually tries to quiesce hw
queues via blk_mq_quiesce_queue(), checking with blk_queue_quiesced()
to avoid unnecessary queue quiesce isn't reliable because: the
QUEUE_FLAG_QUIESCED flag is set before synchronize_rcu() and
dm_stop_queue() may be called when synchronize_rcu() from another
blk_mq_quiesce_queue() is in-progress.
Fixes: 7b17c2f7292ba ("dm: Fix a race condition related to stopping and starting queues")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/md/dm-rq.c | 3 |
1 files changed, 0 insertions, 3 deletions
diff --git a/drivers/md/dm-rq.c b/drivers/md/dm-rq.c index eadfcfd106ff..cac8ec16e603 100644 --- a/drivers/md/dm-rq.c +++ b/drivers/md/dm-rq.c @@ -95,9 +95,6 @@ static void dm_old_stop_queue(struct request_queue *q) static void dm_mq_stop_queue(struct request_queue *q) { - if (blk_mq_queue_stopped(q)) - return; - blk_mq_quiesce_queue(q); } |