2022-11-08 18:15:14

by Khazhy Kumykov

Subject: [PATCH 2/2] bfq: ignore oom_bfqq in bfq_check_waker

oom_bfqq is just a fallback bfqq, so shouldn't be used with waker
detection.

Suggested-by: Jan Kara <[email protected]>
Signed-off-by: Khazhismel Kumykov <[email protected]>
---
block/bfq-iosched.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index ca04ec868c40..267baf84870f 100644
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -2135,7 +2135,9 @@ static void bfq_check_waker(struct bfq_data *bfqd, struct bfq_queue *bfqq,
if (!bfqd->last_completed_rq_bfqq ||
bfqd->last_completed_rq_bfqq == bfqq ||
bfq_bfqq_has_short_ttime(bfqq) ||
- now_ns - bfqd->last_completion >= 4 * NSEC_PER_MSEC)
+ now_ns - bfqd->last_completion >= 4 * NSEC_PER_MSEC ||
+ bfqd->last_completed_rq_bfqq == &bfqd->oom_bfqq ||
+ bfqq == &bfqd->oom_bfqq)
return;

/*
--
2.38.1.431.g37b22c650d-goog

2022-11-09 11:55:02

by Jan Kara

Subject: Re: [PATCH 2/2] bfq: ignore oom_bfqq in bfq_check_waker

On Tue 08-11-22 10:10:30, Khazhismel Kumykov wrote:
> oom_bfqq is just a fallback bfqq, so shouldn't be used with waker
> detection.
>
> Suggested-by: Jan Kara <[email protected]>
> Signed-off-by: Khazhismel Kumykov <[email protected]>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <[email protected]>

Honza

> ---
> block/bfq-iosched.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
> index ca04ec868c40..267baf84870f 100644
> --- a/block/bfq-iosched.c
> +++ b/block/bfq-iosched.c
> @@ -2135,7 +2135,9 @@ static void bfq_check_waker(struct bfq_data *bfqd, struct bfq_queue *bfqq,
> if (!bfqd->last_completed_rq_bfqq ||
> bfqd->last_completed_rq_bfqq == bfqq ||
> bfq_bfqq_has_short_ttime(bfqq) ||
> - now_ns - bfqd->last_completion >= 4 * NSEC_PER_MSEC)
> + now_ns - bfqd->last_completion >= 4 * NSEC_PER_MSEC ||
> + bfqd->last_completed_rq_bfqq == &bfqd->oom_bfqq ||
> + bfqq == &bfqd->oom_bfqq)
> return;
>
> /*
> --
> 2.38.1.431.g37b22c650d-goog
>
--
Jan Kara <[email protected]>
SUSE Labs, CR