Re: [PATCH v7 7/8] blktrace: ensure our debugfs dir exists
From: Bart Van Assche <bvanassche@acm.org>
Date: 2020-06-20 17:33:37
Also in:
linux-fsdevel, linux-mm, lkml
On 2020-06-19 13:47, Luis Chamberlain wrote:
quoted hunk ↗ jump to hunk
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index e6e2d25fdbd6..098780ec018f 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c@@ -538,6 +538,18 @@ static int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, #endif bt->dir = dir = debugfs_create_dir(buts->name, blk_debugfs_root); + /* + * As blktrace relies on debugfs for its interface the debugfs directory + * is required, contrary to the usual mantra of not checking for debugfs + * files or directories. + */ + if (IS_ERR_OR_NULL(dir)) { + pr_warn("debugfs_dir not present for %s so skipping\n", + buts->name);
Maybe mention in the message what is being skipped (block tracing)?
+ ret = -ENOENT; + goto err; + } + bt->dev = dev; atomic_set(&bt->dropped, 0); INIT_LIST_HEAD(&bt->running_list);
Anyway: Reviewed-by: Bart Van Assche <bvanassche@acm.org>