Re: [RFC PATCH v2 2/6] sched: Introduce energy models of CPUs

From: Peter Zijlstra
Date: Tue Apr 10 2018 - 07:55:15 EST


On Fri, Apr 06, 2018 at 04:36:03PM +0100, Dietmar Eggemann wrote:
> + /*
> + * Build the energy model of one CPU, and link it to all CPUs
> + * in its frequency domain. This should be correct as long as
> + * they share the same micro-architecture.
> + */

Aside from the whole PM_OPP question; you should assert that assumption.
Put an explicit check for the uarch in and FAIL the init if that isn't
met.

I don't think it makes _ANY_ kind of sense to share a frequency domain
across uarchs and we should be very clear we're not going to support
anything like that.

I know DynamiQ strictly speaking allows that, but since it's insane, we
should consider that a bug in DynamiQ.