Re: [PATCH v3] sched/core: add forced idle accounting for cgroups

[Tejun Heo]

Hello,

On Tue, Jun 21, 2022 at 04:44:43PM -0700, Josh Don wrote:
> 4feee7d1260 previously added per-task forced idle accounting. This patch
> extends this to also include cgroups.
> 
> rstat is used for cgroup accounting, except for the root, which uses
> kcpustat in order to bypass the need for doing an rstat flush when
> reading root stats.
> 
> Only cgroup v2 is supported. Similar to the task accounting, the cgroup
> accounting requires that schedstats is enabled.

Generally looks fine from cgroup side. One nitpick follow.

> +	seq_printf(seq, "forceidle_usec %llu\n", forceidle_time);

Would it make sense to namespace the name to reflect the fact that
this is tied to core scheduling? e.g. something like
core.force_idle_usec (and yeah, underscore between words, please). I
kinda hate that the feature is named "core". The word is so
overloaded.

Thanks.

-- 
tejun