Re: [PATCH 2/2] sched/fair: Update comments regarding last and skip buddy
From: Madadi Vineeth Reddy
Date: Mon Nov 25 2024 - 05:01:30 EST
Hi Adam Li,
On 25/11/24 07:42, Adam Li wrote:
> Commit 5e963f2bd465 ("sched/fair: Commit to EEVDF") removed the "last" and
> "skip" buddy. Update comments in pick_next_entity().
>
> Signed-off-by: Adam Li <adamli@xxxxxxxxxxxxxxxxxxxxxx>
> ---
> kernel/sched/fair.c | 8 +-------
> 1 file changed, 1 insertion(+), 7 deletions(-)
>
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index cd1188b7f3df..d8826a8e0c77 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -5602,17 +5602,11 @@ set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
>
> static int dequeue_entities(struct rq *rq, struct sched_entity *se, int flags);
>
> -/*
> - * Pick the next process, keeping these things in mind, in this order:
> - * 1) keep things fair between processes/task groups
> - * 2) pick the "next" process, since someone really wants that to run
> - * 3) pick the "last" process, for cache locality
> - * 4) do not run the "skip" process, if something else is available
> - */
> static struct sched_entity *
> pick_next_entity(struct rq *rq, struct cfs_rq *cfs_rq)
> {
> /*
> + * Pick the "next" buddy, since someone really wants that to run.
> * Enabling NEXT_BUDDY will affect latency but not fairness.
> */
Yes, the LAST_BUDDY and SKIP_BUDDY are obsolete now.
Reviewed-by: Madadi Vineeth Reddy <vineethr@xxxxxxxxxxxxx>
Thanks,
Madadi Vineeth Reddy
> if (sched_feat(NEXT_BUDDY) &&