于 2025年5月15日 GMT+08:00 21:42:02，Jens Axboe <axboe@xxxxxxxxx> 写道：
>If blk-throttle is enabled but blktrace is not, then the compiler will
>notice that the following two variables are unused:
>
>../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);
> | ^~~~~~~~~
>
>Silence that my annotating them with __maybe_unused.
>
>Fixes: 28ad83b774a6 ("blk-throttle: Split the service queue")
>Link: https://lore.kernel.org/all/20250515130830.9671-1-aishwarya.tcv@xxxxxxx/
>Reported-by: Aishwarya <aishwarya.tcv@xxxxxxx>
>Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
>
>---
>
Thanks for the fix
Reviewed-by: Yu Kuai <yukuai3@xxxxxxxxxx>
>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);
>
