Re: [PATCH] sched: cgroup SCHED_IDLE support

[Dietmar Eggemann]

Hi Josh,

On 09/06/2021 01:11, Josh Don wrote:

[...]

>  static void __maybe_unused cpu_period_quota_print(struct seq_file *sf,
> @@ -10306,6 +10318,12 @@ static struct cftype cpu_files[] = {
>  		.read_s64 = cpu_weight_nice_read_s64,
>  		.write_s64 = cpu_weight_nice_write_s64,
>  	},
> +	{
> +		.name = "idle",
> +		.flags = CFTYPE_NOT_ON_ROOT,
> +		.read_s64 = cpu_idle_read_s64,
> +		.write_s64 = cpu_idle_write_s64,
> +	},

Any reason why this should only work on cgroup-v2?

struct cftype cpu_legacy_files[] vs. cpu_files[]

[...]

> @@ -11340,10 +11408,14 @@ void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
>  
>  static DEFINE_MUTEX(shares_mutex);
>  
> -int sched_group_set_shares(struct task_group *tg, unsigned long shares)
> +#define IDLE_WEIGHT sched_prio_to_weight[ARRAY_SIZE(sched_prio_to_weight) - 1]

Why not 3 ? Like for tasks (WEIGHT_IDLEPRIO)?

[...]