blk-throttle: don't parse cgroup path if trace isn't enabled
if trace isn't enabled, parsing cgroup path just wastes cpu
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 2149a1d..47a3e54 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -211,15 +211,14 @@
*
* The messages are prefixed with "throtl BLKG_NAME" if @sq belongs to a
* throtl_grp; otherwise, just "throtl".
- *
- * TODO: this should be made a function and name formatting should happen
- * after testing whether blktrace is enabled.
*/
#define throtl_log(sq, fmt, args...) do { \
struct throtl_grp *__tg = sq_to_tg((sq)); \
struct throtl_data *__td = sq_to_td((sq)); \
\
(void)__td; \
+ if (likely(!blk_trace_note_message_enabled(__td->queue))) \
+ break; \
if ((__tg)) { \
char __pbuf[128]; \
\