A later patch will call blk_freeze_queue_start() followed by blk_mq_unfreeze_queue() without waiting for q_usage_counter to drop to zero. Make sure that this doesn't cause a kernel warning to appear by switching from percpu_ref_reinit() to percpu_ref_resurrect(). The former namely requires that the refcount it operates on is zero.
Signed-off-by: Bart Van Assche <[email protected]> Cc: Christoph Hellwig <[email protected]> Cc: Ming Lei <[email protected]> Cc: Jianchao Wang <[email protected]> Cc: Hannes Reinecke <[email protected]> Cc: Johannes Thumshirn <[email protected]> --- block/blk-mq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 85a1c1a59c72..96d501e8663c 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -198,7 +198,7 @@ void blk_mq_unfreeze_queue(struct request_queue *q) freeze_depth = atomic_dec_return(&q->mq_freeze_depth); WARN_ON_ONCE(freeze_depth < 0); if (!freeze_depth) { - percpu_ref_reinit(&q->q_usage_counter); + percpu_ref_resurrect(&q->q_usage_counter); wake_up_all(&q->mq_freeze_wq); } } -- 2.19.0.444.g18242da7ef-goog
