diff options
| author | Christoph Hellwig <hch@lst.de> | 2022-06-14 09:48:25 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-06-17 07:31:05 -0600 |
| commit | 5cf9c91ba927119fc6606b938b1895bb2459d3bc (patch) | |
| tree | c6d3d7b1806f35e8fff9c439285324c6feeddad5 /block/blk-rq-qos.h | |
| parent | 50e34d78815e474d410f342fbe783b18192ca518 (diff) | |
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.h')
| -rw-r--r-- | block/blk-rq-qos.h | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/block/blk-rq-qos.h b/block/blk-rq-qos.h index 68267007da1c..0e46052b018a 100644 --- a/block/blk-rq-qos.h +++ b/block/blk-rq-qos.h @@ -104,8 +104,11 @@ static inline void rq_qos_add(struct request_queue *q, struct rq_qos *rqos) blk_mq_unfreeze_queue(q); - if (rqos->ops->debugfs_attrs) + if (rqos->ops->debugfs_attrs) { + mutex_lock(&q->debugfs_mutex); blk_mq_debugfs_register_rqos(rqos); + mutex_unlock(&q->debugfs_mutex); + } } static inline void rq_qos_del(struct request_queue *q, struct rq_qos *rqos) @@ -129,7 +132,9 @@ static inline void rq_qos_del(struct request_queue *q, struct rq_qos *rqos) blk_mq_unfreeze_queue(q); + mutex_lock(&q->debugfs_mutex); blk_mq_debugfs_unregister_rqos(rqos); + mutex_unlock(&q->debugfs_mutex); } typedef bool (acquire_inflight_cb_t)(struct rq_wait *rqw, void *private_data); |