On Mar 16, 2022 / 15:11, Shin'ichiro Kawasaki wrote:
(snip)
> diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
> index 55488ba97823..64941615befc 100644
> --- a/block/blk-mq-sched.c
> +++ b/block/blk-mq-sched.c
> @@ -181,9 +181,15 @@ static int __blk_mq_do_dispatch_sched(struct blk_mq_hw_ctx *hctx)
> static int blk_mq_do_dispatch_sched(struct blk_mq_hw_ctx *hctx)
> {
> int ret;
> + unsigned long end = jiffies + HZ;
>
> do {
> ret = __blk_mq_do_dispatch_sched(hctx);
> + if (ret == 1 &&
> + (need_resched() || time_is_after_jiffies(end))) {
I've noticed that I made a horrible mistake. The time_is_after_jiffies(end) in
the line above is wrong. It should be time_is_before_jiffies(end). My bad.
Before I post v2 with this fix, I will ensure the fix by checking call frequency
of blk_mq_delay_run_hw_queue using kprobe.
> + blk_mq_delay_run_hw_queue(hctx, 0);
> + break;
> + }
> } while (ret == 1);
>
> return ret;
> --
> 2.34.1
>
--
Best Regards,
Shin'ichiro Kawasaki
