Re: [PATCH] PM / arch: x86: Rework the MSR_IA32_ENERGY_PERF_BIAS handling

[Thomas Gleixner]

On Thu, 21 Mar 2019, Rafael J. Wysocki wrote:

> On Thu, Mar 21, 2019 at 8:58 AM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> >
> > On Thu, Mar 21, 2019 at 01:00:52AM +0100, Rafael J. Wysocki wrote:
> > > + * The Performance and Energy Bias Hint (EPB) allows software to specify its
> > > + * preference with respect to the power-performance tradeoffs present in the
> > > + * processor.  Generally, the EPB is expected to be set by user space through
> > > + * the generic MSR interface (with the help of the x86_energy_perf_policy tool),
> > > + * but there are two reasons for the kernel to touch it.
> >
> > So I hate /dev/msr with a passion. It is absolute atrocious crap.
> >
> > Please, just make a real interface for this if it is important.
> 
> That's the plan going forward, this is just documenting the current situation.
> 
> Do you have any particular concerns regarding this patch?

No.

Acked-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>