diff options
Diffstat (limited to 'block/blk-mq-tag.c')
-rw-r--r-- | block/blk-mq-tag.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 4bc701b32ce2..89bb6250633d 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -336,6 +336,13 @@ void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn, struct blk_mq_hw_ctx *hctx; int i; + /* + * __blk_mq_update_nr_hw_queues will update the nr_hw_queues and + * queue_hw_ctx after freeze the queue, so we use q_usage_counter + * to avoid race with it. + */ + if (!percpu_ref_tryget(&q->q_usage_counter)) + return; queue_for_each_hw_ctx(q, hctx, i) { struct blk_mq_tags *tags = hctx->tags; @@ -351,7 +358,7 @@ void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn, bt_for_each(hctx, &tags->breserved_tags, fn, priv, true); bt_for_each(hctx, &tags->bitmap_tags, fn, priv, false); } - + blk_queue_exit(q); } static unsigned int bt_unused_tags(const struct sbitmap_queue *bt) |