diff options
| author | Christoph Hellwig <hch@lst.de> | 2022-06-14 09:48:25 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-06-17 15:31:05 +0200 |
| commit | 5cf9c91ba927119fc6606b938b1895bb2459d3bc (patch) | |
| tree | c6d3d7b1806f35e8fff9c439285324c6feeddad5 /block/blk-rq-qos.c | |
| parent | block: disable the elevator int del_gendisk (diff) | |
| download | linux-5cf9c91ba927119fc6606b938b1895bb2459d3bc.tar.xz linux-5cf9c91ba927119fc6606b938b1895bb2459d3bc.zip | |
block: serialize all debugfs operations using q->debugfs_mutex
Various places like I/O schedulers or the QOS infrastructure try to
register debugfs files on demans, which can race with creating and
removing the main queue debugfs directory. Use the existing
debugfs_mutex to serialize all debugfs operations that rely on
q->debugfs_dir or the directories hanging off it.
To make the teardown code a little simpler declare all debugfs dentry
pointers and not just the main one uncoditionally in blkdev.h.
Move debugfs_mutex next to the dentries that it protects and document
what it is used for.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220614074827.458955-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk-rq-qos.c')
| -rw-r--r-- | block/blk-rq-qos.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/block/blk-rq-qos.c b/block/blk-rq-qos.c index e83af7bc7591..249a6f05dd3b 100644 --- a/block/blk-rq-qos.c +++ b/block/blk-rq-qos.c @@ -294,7 +294,9 @@ void rq_qos_wait(struct rq_wait *rqw, void *private_data, void rq_qos_exit(struct request_queue *q) { + mutex_lock(&q->debugfs_mutex); blk_mq_debugfs_unregister_queue_rqos(q); + mutex_unlock(&q->debugfs_mutex); while (q->rq_qos) { struct rq_qos *rqos = q->rq_qos; |