Commit 60f2df8a authored May 11, 2014 by Ming Lei Committed by Jens Axboe May 10, 2014

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>

parent 0289b2e1

block/blk-mq-tag.c

+0 −1

Original line number	Diff line number	Diff line
		@@ -244,7 +244,6 @@ static void bt_clear_tag(struct blk_mq_bitmap_tags *bt, unsigned int tag)

		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);