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

[Peter Zijlstra]

On Thu, Aug 02, 2018 at 04:21:11PM +0100, Quentin Perret wrote:
> On Thursday 02 Aug 2018 at 14:45:11 (+0200), Peter Zijlstra wrote:

> > To clarify, it makes absolutely no sense what so ever to attempt EAS
> > when the DVFS control is not coordinated.
> 
> I tend to agree with that, but at the same time even if we create a very
> strong dependency on schedutil, we will have no guarantee that the actual
> frequencies used on the platform are the ones we predicted in EAS.

Sure; on x86 for example our micro-code does whatever. But using
schedutil we at least 'guide' it in the general direction we'd expect
with the control that is available.

Using a !schedutil governor doesn't even get us that and we're basically
running on random input without any feedback to close the loop. Not
something I feel we should support or care for.