blk-mq-debugfs: fix device sched directory for default scheduler

In blk_mq_debugfs_register(), I remembered to set up the per-hctx sched
directories if a default scheduler was already configured by
blk_mq_sched_init() from blk_mq_init_allocated_queue(), but I didn't do
the same for the device-wide sched directory. Fix it.

Fixes: d332ce091813 ("blk-mq-debugfs: allow schedulers to register debugfs attributes")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 5 insertions, 1 deletions

diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c
index 980e73095643..de294d775acf 100644
--- a/block/blk-mq-debugfs.c
+++ b/block/blk-mq-debugfs.c
@@ -815,10 +815,14 @@ int blk_mq_debugfs_register(struct request_queue *q)
                 goto err;
 
         /*
-         * blk_mq_init_hctx() attempted to do this already, but q->debugfs_dir
+         * blk_mq_init_sched() attempted to do this already, but q->debugfs_dir
          * didn't exist yet (because we don't know what to name the directory
          * until the queue is registered to a gendisk).
          */
+        if (q->elevator && !q->sched_debugfs_dir)
+                blk_mq_debugfs_register_sched(q);
+
+        /* Similarly, blk_mq_init_hctx() couldn't do this previously. */
         queue_for_each_hw_ctx(q, hctx, i) {
                 if (!hctx->debugfs_dir && blk_mq_debugfs_register_hctx(q, hctx))
                         goto err;