diff options
| author | Omar Sandoval <osandov@fb.com> | 2017-02-01 01:53:22 +0300 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2017-02-02 20:20:16 +0300 |
| commit | 6ac93117ab009d3901ed5d3d0f79056eb5fc0afd (patch) | |
| tree | 1f5e064f9ecbbd55d8d72a23a4f3b7f66d411384 | |
| parent | 62ebce16c0ac2ffac44e32f931a2d8f6e749be4c (diff) | |
| download | linux-6ac93117ab009d3901ed5d3d0f79056eb5fc0afd.tar.xz | |
blktrace: use existing disk debugfs directory
We may already have a directory to put the blktrace stuff in if
1. The disk uses blk-mq
2. CONFIG_BLK_DEBUG_FS is enabled
3. We are tracing the whole disk and not a partition
Instead of hardcoding this very specific case, let's use the new
debugfs_lookup(). If the directory exists, we use it, otherwise we
create one and clean it up later.
Fixes: 07e4fead45e6 ("blk-mq: create debugfs directory tree")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
| -rw-r--r-- | kernel/trace/blktrace.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index 8cea91d248d9..b2058a7f94bd 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -470,12 +470,12 @@ static int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, if (!blk_debugfs_root) goto err; - dir = debugfs_create_dir(buts->name, blk_debugfs_root); - + dir = debugfs_lookup(buts->name, blk_debugfs_root); + if (!dir) + bt->dir = dir = debugfs_create_dir(buts->name, blk_debugfs_root); if (!dir) goto err; - bt->dir = dir; bt->dev = dev; atomic_set(&bt->dropped, 0); INIT_LIST_HEAD(&bt->running_list); @@ -517,9 +517,12 @@ static int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, if (atomic_inc_return(&blk_probes_ref) == 1) blk_register_tracepoints(); - return 0; + ret = 0; err: - blk_trace_free(bt); + if (dir && !bt->dir) + dput(dir); + if (ret) + blk_trace_free(bt); return ret; } |