block: only allocate/free mq_usage_counter in blk-mq

The percpu counter is only used for blk-mq, so move
its allocation and free inside blk-mq, and don't
allocate it for legacy queue device.

Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 07851753a049..e8b5f74dc1a1 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1781,6 +1781,9 @@ struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set)
         if (!q)
                 goto err_hctxs;
 
+        if (percpu_counter_init(&q->mq_usage_counter, 0))
+                goto err_map;
+
         q->mq_map = blk_mq_make_queue_map(set);
         if (!q->mq_map)
                 goto err_map;
@@ -1867,6 +1870,8 @@ void blk_mq_free_queue(struct request_queue *q)
         blk_mq_exit_hw_queues(q, set, set->nr_hw_queues);
         blk_mq_free_hw_queues(q, set);
 
+        percpu_counter_destroy(&q->mq_usage_counter);
+
         free_percpu(q->queue_ctx);
         kfree(q->queue_hw_ctx);
         kfree(q->mq_map);