directio: add block polling support

[cascardo/linux.git] / block / blk-mq-tag.c

diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c
index ec2d119..60ac684 100644 (file)
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -75,6 +75,10 @@ void blk_mq_tag_wakeup_all(struct blk_mq_tags *tags, bool include_reserve)
        struct blk_mq_bitmap_tags *bt;
        int i, wake_index;
 
+       /*
+        * Make sure all changes prior to this are visible from other CPUs.
+        */
+       smp_mb();
        bt = &tags->bitmap_tags;
        wake_index = atomic_read(&bt->wake_index);
        for (i = 0; i < BT_WAIT_QUEUES; i++) {