Hi,
On Tue, Sep 10, 2024 at 03:48:32PM +0800 Liu Song wrote:
> For the handling logic of child_quota, there is no need to distinguish
> between cgroup1 and cgroup2, so unify the handling logic here.
>
> Signed-off-by: Liu Song <liusong@xxxxxxxxxxxxxxxxx>
> ---
> kernel/sched/core.c | 21 +++++----------------
> 1 file changed, 5 insertions(+), 16 deletions(-)
>
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index e752146e59a4..8418c67faa69 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -9501,23 +9501,12 @@ static int tg_cfs_schedulable_down(struct task_group *tg, void *data)
> parent_quota = parent_b->hierarchical_quota;
>
> /*
> - * Ensure max(child_quota) <= parent_quota. On cgroup2,
> - * always take the non-RUNTIME_INF min. On cgroup1, only
> - * inherit when no limit is set. In both cases this is used
> - * by the scheduler to determine if a given CFS task has a
> - * bandwidth constraint at some higher level.
This comment is here for a reason. Please don't remove it.
> + * Ensure max(child_quota) <= parent_quota.
> */
> - if (cgroup_subsys_on_dfl(cpu_cgrp_subsys)) {
> - if (quota == RUNTIME_INF)
> - quota = parent_quota;
> - else if (parent_quota != RUNTIME_INF)
> - quota = min(quota, parent_quota);
> - } else {
> - if (quota == RUNTIME_INF)
> - quota = parent_quota;
> - else if (parent_quota != RUNTIME_INF && quota > parent_quota)
> - return -EINVAL;
> - }
> + if (quota == RUNTIME_INF)
> + quota = parent_quota;
> + else if (parent_quota != RUNTIME_INF)
> + quota = min(quota, parent_quota);
> }
> cfs_b->hierarchical_quota = quota;
>
I don't think there is a need to optimize this slow path
to allow setting invalid values which have to be handled in
fast paths. And this will change expected behavior.
So NAK.
Cheers,
Phil
--
