在 2025/5/15 21:39, Jens Axboe 写道:
On 5/15/25 7:08 AM, Aishwarya wrote:
Observed the following build warning when building the next-20250515 kernel with defconfig+CONFIG_BLK_DEV_THROTTLING applied:
Warning output:
../block/blk-throttle.c: In function 'throtl_pending_timer_fn':
../block/blk-throttle.c:1153:30: warning: unused variable 'bio_cnt_w' [-Wunused-variable]
1153 | unsigned int bio_cnt_w = sq_queued(sq, WRITE);
| ^~~~~~~~~
../block/blk-throttle.c:1152:30: warning: unused variable 'bio_cnt_r' [-Wunused-variable]
1152 | unsigned int bio_cnt_r = sq_queued(sq, READ);
| ^~~~~~~~~
There?s no warning with defconfig alone, and I?ve confirmed that the warning appears when CONFIG_BLK_DEV_THROTTLING is explicitly enabled.
This should fix it. The issue is if blktrace isn't enabled.
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index bf4faac83662..bd15357f23bd 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -1149,8 +1149,8 @@ static void throtl_pending_timer_fn(struct timer_list *t)
dispatched = false;
while (true) {
- unsigned int bio_cnt_r = sq_queued(sq, READ);
- unsigned int bio_cnt_w = sq_queued(sq, WRITE);
+ unsigned int __maybe_unused bio_cnt_r = sq_queued(sq, READ);
+ unsigned int __maybe_unused bio_cnt_w = sq_queued(sq, WRITE);
throtl_log(sq, "dispatch nr_queued=%u read=%u write=%u",
bio_cnt_r + bio_cnt_w, bio_cnt_r, bio_cnt_w);
Oops.. I didn't take that into account. Those two variables are only
used in throtl_log. I'll check if there are any other similar issues and
send out a fix patch shortly. Thanks for pointing it out!
Thanks,
Zizhi Wo
