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 /kernel/trace | |
| 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 'kernel/trace')
| -rw-r--r-- | kernel/trace/blktrace.c | 3 |
1 files changed, 0 insertions, 3 deletions
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index 10a32b0f2deb..fe04c6f96ca5 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -770,14 +770,11 @@ int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) **/ void blk_trace_shutdown(struct request_queue *q) { - mutex_lock(&q->debugfs_mutex); if (rcu_dereference_protected(q->blk_trace, lockdep_is_held(&q->debugfs_mutex))) { __blk_trace_startstop(q, 0); __blk_trace_remove(q); } - - mutex_unlock(&q->debugfs_mutex); } #ifdef CONFIG_BLK_CGROUP |