1 files changed, 12 insertions, 2 deletions

diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index 6deb13055490..08fc6716d362 100644
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -344,6 +344,7 @@ static void bt_clear_tag(struct blk_mq_bitmap_tags *bt, unsigned int tag)
 {
         const int index = TAG_TO_INDEX(bt, tag);
         struct bt_wait_state *bs;
+        int wait_cnt;
 
         /*
          * The unlock memory barrier need to order access to req in free
@@ -352,10 +353,19 @@ static void bt_clear_tag(struct blk_mq_bitmap_tags *bt, unsigned int tag)
         clear_bit_unlock(TAG_TO_BIT(bt, tag), &bt->map[index].word);
 
         bs = bt_wake_ptr(bt);
-        if (bs && atomic_dec_and_test(&bs->wait_cnt)) {
-                atomic_set(&bs->wait_cnt, bt->wake_cnt);
+        if (!bs)
+                return;
+
+        wait_cnt = atomic_dec_return(&bs->wait_cnt);
+        if (wait_cnt == 0) {
+wake:
+                atomic_add(bt->wake_cnt, &bs->wait_cnt);
                 bt_index_atomic_inc(&bt->wake_index);
                 wake_up(&bs->wait);
+        } else if (wait_cnt < 0) {
+                wait_cnt = atomic_inc_return(&bs->wait_cnt);
+                if (!wait_cnt)
+                        goto wake;
         }
 }