[PATCH v2 09/10] block: panic if block debugfs dir is not created

From: Luis Chamberlain <mcgrof@kernel.org>
To: axboe@kernel.dk, viro@zeniv.linux.org.uk, bvanassche@acm.org,
	gregkh@linuxfoundation.org, rostedt@goodmis.org,
	mingo@redhat.com, jack@suse.cz, ming.lei@redhat.com,
	nstange@suse.de, akpm@linux-foundation.org
Cc: mhocko@suse.com, yukuai3@huawei.com, linux-block@vger.kernel.org,
	linux-fsdevel@vger.kernel.org, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org,
	Luis Chamberlain <mcgrof@kernel.org>
Subject: [PATCH v2 09/10] block: panic if block debugfs dir is not created
Date: Sun, 19 Apr 2020 19:45:28 +0000	[thread overview]
Message-ID: <20200419194529.4872-10-mcgrof@kernel.org> (raw)
In-Reply-To: <20200419194529.4872-1-mcgrof@kernel.org>

If DEBUG_FS is disabled we have another inline
blk_debugfs_register() which just returns 0.

If BLK_DEV_IO_TRACE is enabled we rely on the block debugfs
directory to have been created. If BLK_DEV_IO_TRACE is not enabled
though, but if debugfs is still enabled we will always create a
debugfs directory for a request_queue. Instead of special-casing
this just for BLK_DEV_IO_TRACE, ensure this block debugfs dir is
always created at boot if we have enabled debugfs.

Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
---
 block/blk-debugfs.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/block/blk-debugfs.c b/block/blk-debugfs.c
index 761318dcbf40..d6ec980e7531 100644
--- a/block/blk-debugfs.c
+++ b/block/blk-debugfs.c
@@ -15,6 +15,8 @@ struct dentry *blk_debugfs_root;
 void blk_debugfs_register(void)
 {
 	blk_debugfs_root = debugfs_create_dir("block", NULL);
+	if (!blk_debugfs_root)
+		panic("Failed to create block debugfs directory\n");
 }
 
 int __must_check blk_queue_debugfs_register(struct request_queue *q)
-- 
2.25.1

