Re: [PATCH 6/7] thermal: netlink: Add a new event to notify CPU capabilities change

From: Ricardo Neri
Date: Thu Dec 09 2021 - 11:11:46 EST


On Tue, Nov 30, 2021 at 10:29:46AM +0100, Daniel Lezcano wrote:
> On 06/11/2021 02:33, Ricardo Neri wrote:
> > From: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx>
> >
> > Add a new netlink event to notify change in CPU capabilities in terms of
> > performance and efficiency.
> >
> > Firmware may change CPU capabilities as a result of thermal events in the
> > system or to account for changes in the TDP (thermal design power) level.
> >
> > This notification type will allow user space to avoid running workloads
> > on certain CPUs or proactively adjust power limits to avoid future events.
> >
>
> [ ... ]
>
> > + [THERMAL_GENL_ATTR_CPU_CAPABILITY_ID] = { .type = NLA_U32 },
> > + [THERMAL_GENL_ATTR_CPU_CAPABILITY_PERF] = { .type = NLA_U32 },
> > + [THERMAL_GENL_ATTR_CPU_CAPABILITY_EFF] = { .type = NLA_U32 },
> > };
>
> AFAIU, 0 <= perf < 256 and 0 <= eff < 256, right?
>
> Is the following true?
>
> 0 <= perf + eff < 256

No, they are not. They are set independently.

Thanks and BR,
Ricardo