blk-mq: bitmap tag: remove barrier in bt_clear_tag()
The barrier isn't necessary because both atomic_dec_and_test()
and wake_up() implicate one barrier.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index a81b138..5a83d8e 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -244,7 +244,6 @@
bs = bt_wake_ptr(bt);
if (bs && atomic_dec_and_test(&bs->wait_cnt)) {
- smp_mb__after_clear_bit();
atomic_set(&bs->wait_cnt, bt->wake_cnt);
bt_index_inc(&bt->wake_index);
wake_up(&bs->wait);