[Devel] Re: [PATCH v3 1/6] measure exec_clock for rt sched entities

[Glauber Costa]

On 05/30/2012 03:00 PM, Paul Turner wrote:
> Does this even need to be hierarchical?  While it's natural for it to
> be in the CFS case, it feels forced here.
>
> You could instead make this rt_rq->local_exec_clock  charging only to
> the parenting rt_rq and post-aggregate when you want to report.  The
> only thing you'd need to be careful of is also accounting children
> somewhere on the parent on destruction (reaped_exec_clock?).
>
> Harking back to symmetry, local_exec_clock is also a potentially
> useful stat on the CFS side of things since it allows you to usefully
> disambiguate versus your children (common case where this is useful is
> calculating usage of threads in the root cgroup); so it wouldn't need
> to be unique to rt_rq.

I can try this approach.