linux-kernel - Re: [RFC][PATCH v0.3 6/6] cpufreq: intel_pstate: EAS support for hybrid platforms

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <CAJZ5v0ghVNKKWbLnwhbriotbgtujy6_G0yiFm1PiCK2KyCPR+A@mail.gmail.com>
Date: Thu, 13 Mar 2025 19:50:38 +0100
From: "Rafael J. Wysocki" <rafael@...nel.org>
To: Tim Chen <tim.c.chen@...ux.intel.com>
Cc: "Rafael J. Wysocki" <rjw@...ysocki.net>, Linux PM <linux-pm@...r.kernel.org>, 
	LKML <linux-kernel@...r.kernel.org>, Lukasz Luba <lukasz.luba@....com>, 
	Peter Zijlstra <peterz@...radead.org>, 
	Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>, 
	Dietmar Eggemann <dietmar.eggemann@....com>, Morten Rasmussen <morten.rasmussen@....com>, 
	Vincent Guittot <vincent.guittot@...aro.org>, 
	Ricardo Neri <ricardo.neri-calderon@...ux.intel.com>, 
	Pierre Gondois <pierre.gondois@....com>, Christian Loehle <christian.loehle@....com>
Subject: Re: [RFC][PATCH v0.3 6/6] cpufreq: intel_pstate: EAS support for
 hybrid platforms

On Thu, Mar 13, 2025 at 7:46 PM Tim Chen <tim.c.chen@...ux.intel.com> wrote:
>
> On Fri, 2025-03-07 at 20:42 +0100, Rafael J. Wysocki wrote:
> >
> >
> > --- a/drivers/cpufreq/intel_pstate.c
> > +++ b/drivers/cpufreq/intel_pstate.c
> > @@ -44,6 +44,8 @@
> >  #define INTEL_CPUFREQ_TRANSITION_DELAY_HWP   5000
> >  #define INTEL_CPUFREQ_TRANSITION_DELAY               500
> >
> > +#define INTEL_PSTATE_CORE_SCALING            100000
> > +
>
> Minor nits.
>
> Suggest move the above define to
>
> #define HYBRID_SCALING_FACTOR_ADL       78741
> #define HYBRID_SCALING_FACTOR_MTL       80000
> #define HYBRID_SCALING_FACTOR_LNL       86957
> #define INTEL_PSTATE_CORE_SCALING       100000
>
> to keep the scaling factors at the same place.

It may be needed earlier, but I see your point.  Keeping them together
will make sense.

>
> > @@ -3425,6 +3539,8 @@
> >
> >               cpufreq_unregister_driver(intel_pstate_driver);
> >               intel_pstate_driver_cleanup();
> > +             /* Trigger EAS support reconfiguration in case it was used. */
>
> May be clearer to say
>
>                 /* Disable EAS support in case it was used */

Sure.

> My first read of the comment thought that we are enabling EAS support.
>
> > +             rebuild_sched_domains_energy();
> >               return 0;
> >       }
> >
>
> Rest of patch looks good.

Thanks for the review!