diff mbox

Blktrace: bail out early if block debugfs is not configured

Message ID 1530237368-105049-1-git-send-email-bo.liu@linux.alibaba.com (mailing list archive)
State New, archived
Headers show

Commit Message

Liu Bo June 29, 2018, 1:56 a.m. UTC 
Since @blk_debugfs_root couldn't be configured dynamically, we can
save a few memory allocation if it's not there.

Signed-off-by: Liu Bo <bo.liu@linux.alibaba.com>
---
 kernel/trace/blktrace.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Comments

Jens Axboe June 29, 2018, 3:02 p.m. UTC | #1 
On 6/28/18 7:56 PM, Liu Bo wrote:
> Since @blk_debugfs_root couldn't be configured dynamically, we can
> save a few memory allocation if it's not there.

Applied for 4.19, thanks.
diff mbox

Patch

diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 987d9a9ae283..b951aa1fac61 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -494,6 +494,9 @@  static int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
 	if (!buts->buf_size || !buts->buf_nr)
 		return -EINVAL;
 
+	if (!blk_debugfs_root)
+		return -ENOENT;
+
 	strncpy(buts->name, name, BLKTRACE_BDEV_SIZE);
 	buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0';
 
@@ -518,9 +521,6 @@  static int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
 
 	ret = -ENOENT;
 
-	if (!blk_debugfs_root)
-		goto err;
-
 	dir = debugfs_lookup(buts->name, blk_debugfs_root);
 	if (!dir)
 		bt->dir = dir = debugfs_create_dir(buts->name, blk_debugfs_root);