From: Ming Lei ming.lei@redhat.com
[ Upstream commit f3ec5d11554778c24ac8915e847223ed71d104fc ]
blk_mq_debugfs_register_hctx() can be called by blk_mq_update_nr_hw_queues when gendisk isn't added yet, such as nvme tcp.
Fixes the warning of 'debugfs: Directory 'hctx0' with parent '/' already present!' which can be observed reliably when running blktests nvme/005.
Fixes: 6cfc0081b046 ("blk-mq: no need to check return value of debugfs_create functions") Reported-by: Yi Zhang yi.zhang@redhat.com Signed-off-by: Ming Lei ming.lei@redhat.com Tested-by: Yi Zhang yi.zhang@redhat.com Reviewed-by: Christoph Hellwig hch@lst.de Link: https://lore.kernel.org/r/20220711090808.259682-1-ming.lei@redhat.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- block/blk-mq-debugfs.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c index aa0349e9f083..34bee263936c 100644 --- a/block/blk-mq-debugfs.c +++ b/block/blk-mq-debugfs.c @@ -737,6 +737,9 @@ void blk_mq_debugfs_register_hctx(struct request_queue *q, char name[20]; int i;
+ if (!q->debugfs_dir) + return; + snprintf(name, sizeof(name), "hctx%u", hctx->queue_num); hctx->debugfs_dir = debugfs_create_dir(name, q->debugfs_dir);