Re: [RFC PATCH 0/7] Introduce thermal pressure

From: Rafael J. Wysocki
Date: Thu Oct 18 2018 - 04:14:42 EST


On Thu, Oct 18, 2018 at 9:50 AM Ingo Molnar <mingo@xxxxxxxxxx> wrote:
>
>
> * Rafael J. Wysocki <rafael@xxxxxxxxxx> wrote:
>
> > > The only long term maintainable solution is to move all high level
> > > cpufreq logic and policy handling code into kernel/sched/cpufreq*.c,
> > > which has been done to a fair degree already in the past ~2 years - but
> > > it's unclear to me to what extent this is true for thermal throttling
> > > policy currently: there might be more governor surgery and code
> > > reshuffling required?
> >
> > It doesn't cover thermal management directly ATM.
> >
> > The EAS work kind of hopes to make a connection in there by adding a
> > common energy model to underlie both the performance scaling and
> > thermal management, but it doesn't change the thermal decision making
> > part AFAICS.
> >
> > So it is fair to say that additional governor surgery and code
> > reshuffling will be required IMO.
>
> BTW., when factoring out high level thermal management code it might make
> sense to increase the prominence of the cpufreq code within the scheduler
> and organize it a bit better, by introducing its own
> kernel/sched/cpufreq/ directory and renaming things the following way:
>
> kernel/sched/cpufreq.c => kernel/sched/cpufreq/core.c
> kernel/sched/cpufreq_schedutil.c => kernel/sched/cpufreq/metrics.c
> kernel/sched/thermal.c => kernel/sched/cpufreq/thermal.c
>
> ... or so?
>
> With no change to functionality, this is just a re-organization and
> expansion/preparation for the bright future. =B-)

No disagreement here. :-)

Cheers,
Rafael