Re: [PATCH v1] cpufreq: intel_pstate: Rearrange checks in hybrid_get_cost()

[Rafael J. Wysocki (Intel)]

On Wed, Jul 1, 2026 at 8:08 PM srinivas pandruvada
<srinivas.pandruvada@xxxxxxxxxxxxxxx> wrote:
>
> On Wed, 2026-06-17 at 19:02 +0200, Rafael J. Wysocki wrote:
> > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> >
> > Make the checks in hybrid_get_cost() more straightforward.
> >
>
> Please do the same for hwp_get_cpu_scaling()
>
> if (hybrid_get_cpu_type(cpu) != INTEL_CPU_TYPE_ATOM)
> to
> if (hybrid_get_cpu_type(cpu) == INTEL_CPU_TYPE_CORE)

I don't think this is necessary and it would break Razor Lake-E - see
commit 0e7c710478b3 ("cpufreq: intel_pstate: Use correct scaling
factor on Raptor Lake-E") - and Bartlett Lake.

The check in hwp_get_cpu_scaling() is only done for the processors
having nonzero hybrid_scaling_factor that are explicitly listed in
intel_hybrid_scaling_factor[] and on those the TYPE_ATOM cores all
have the default scaling factor.

I'm going to apply the patch as is.

Thanks!

> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> > ---
> >  drivers/cpufreq/intel_pstate.c |    8 +++-----
> >  1 file changed, 3 insertions(+), 5 deletions(-)
> >
> > --- a/drivers/cpufreq/intel_pstate.c
> > +++ b/drivers/cpufreq/intel_pstate.c
> > @@ -979,12 +979,10 @@ static int hybrid_get_cost(struct device
> >        * capacity.  Similarly, P-cores start to be populated when
> > E-cores are
> >        * utilized above 60% of the capacity.
> >        */
> > -     if (hybrid_get_cpu_type(dev->id) == INTEL_CPU_TYPE_ATOM) {
> > -             if (hybrid_has_l3(dev->id)) /* E-core */
> > -                     *cost += 1;
> > -     } else { /* P-core */
> > +     if (hybrid_get_cpu_type(dev->id) == INTEL_CPU_TYPE_CORE) /*
> > P-core */
> >               *cost += 2;
> > -     }
> > +     else if (hybrid_has_l3(dev->id)) /* E-core */
> > +             *cost += 1;
> >
> >       return 0;
> >  }
> >
> >
> >