[PATCH AUTOSEL for 4.9 16/33] block: wake up all tasks blocked in get_request()

[alexander . levin]

From: Ming Lei <ming....@redhat.com>

[ Upstream commit 34d9715ac1edd50285168dd8d80c972739a4f6a4 ]

Once blk_set_queue_dying() is done in blk_cleanup_queue(), we call
blk_freeze_queue() and wait for q->q_usage_counter becoming zero. But
if there are tasks blocked in get_request(), q->q_usage_counter can
never become zero. So we have to wake up all these tasks in
blk_set_queue_dying() first.

Fixes: 3ef28e83ab157997 ("block: generic request_queue reference counting")
Signed-off-by: Ming Lei <ming....@redhat.com>
Signed-off-by: Jens Axboe <ax...@kernel.dk>
Signed-off-by: Sasha Levin <alexander.le...@verizon.com>
---
 block/blk-core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index b1c76aa73492..23daf40be371 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -527,8 +527,8 @@ void blk_set_queue_dying(struct request_queue *q)
 
                blk_queue_for_each_rl(rl, q) {
                        if (rl->rq_pool) {
-                               wake_up(&rl->wait[BLK_RW_SYNC]);
-                               wake_up(&rl->wait[BLK_RW_ASYNC]);
+                               wake_up_all(&rl->wait[BLK_RW_SYNC]);
+                               wake_up_all(&rl->wait[BLK_RW_ASYNC]);
                        }
                }
        }
-- 
2.11.0