Re: [PATCH v5 10/14] sched/cpufreq: Refactor the utilization aggregation method

[Rafael J. Wysocki]

On Tue, Jul 31, 2018 at 9:31 PM,  <skannan@xxxxxxxxxxxxxx> wrote:
> On 2018-07-31 00:59, Quentin Perret wrote:
>>
>> On Monday 30 Jul 2018 at 12:35:27 (-0700), skannan@xxxxxxxxxxxxxx wrote:
>> [...]
>>>
>>> If it's going to be a different aggregation from what's done for
>>> frequency
>>> guidance, I don't see the point of having this inside schedutil. Why not
>>> keep it inside the scheduler files?
>>
>>
>> This code basically results from a discussion we had with Peter on v4.
>> Keeping everything centralized can make sense from a maintenance
>> perspective, I think. That makes it easy to see the impact of any change
>> to utilization signals for both EAS and schedutil.
>
>
> In that case, I'd argue it makes more sense to keep the code centralized in
> the scheduler. The scheduler can let schedutil know about the utilization
> after it aggregates them. There's no need for a cpufreq governor to know
> that there are scheduling classes or how many there are. And the scheduler
> can then choose to aggregate one way for task packing and another way for
> frequency guidance.

Also the aggregate utilization may be used by cpuidle governors in
principle to decide how deep they can go with idle state selection.