Re: [RFC v3 0/5] Add capacity capping support to the CPU controller
From: Patrick Bellasi
Date: Wed Apr 12 2017 - 09:27:53 EST
On 12-Apr 14:48, Peter Zijlstra wrote:
> On Tue, Apr 11, 2017 at 06:58:33PM +0100, Patrick Bellasi wrote:
> > > illustrated per your above points in that it affects both, while in
> > > fact it actually modifies another metric, namely util_avg.
> >
> > I don't see it modifying in any direct way util_avg.
>
> The point is that clamps called 'capacity' are applied to util. So while
> you don't modify util directly, you do modify the util signal (for one
> consumer).
Right, but this consumer (i.e. schedutil) it's already translating
the util_avg into a next_freq (which ultimately it's a capacity).
Thus, I don't see a big misfit in that code path to "filter" this
translation with a capacity clamp.
--
#include <best/regards.h>
Patrick Bellasi