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

From: Peter Zijlstra
Date: Thu Mar 21 2019 - 03:58:23 EST


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.