Re: cpufreq/thermal regression in 6.10

From: Johan Hovold
Date: Tue Jun 11 2024 - 08:02:28 EST


On Tue, Jun 11, 2024 at 12:54:25PM +0200, Rafael J. Wysocki wrote:
> On Mon, Jun 10, 2024 at 1:17 PM Rafael J. Wysocki <rafael@xxxxxxxxxx> wrote:
> > On Sun, Jun 9, 2024 at 9:53 AM Johan Hovold <johan@xxxxxxxxxx> wrote:

> > > Steev reported to me off-list that the CPU frequency of the big cores on
> > > the Lenovo ThinkPad X13s sometimes appears to get stuck at a low
> > > frequency with 6.10-rc2.
> > >
> > > I just confirmed that once the cores are fully throttled (using the
> > > stepwise thermal governor) due to the skin temperature reaching the
> > > first trip point, scaling_max_freq gets stuck at the next OPP:
> > >
> > > cpu4/cpufreq/scaling_max_freq:940800
> > > cpu5/cpufreq/scaling_max_freq:940800
> > > cpu6/cpufreq/scaling_max_freq:940800
> > > cpu7/cpufreq/scaling_max_freq:940800
> > >
> > > when the temperature drops again.

> If this is the step-wise governor, the problem might have been
> introduced by commit
>
> 042a3d80f118 thermal: core: Move passive polling management to the core
>
> which removed passive polling count updates from that governor, so if
> the thermal zone in question has passive polling only and no regular
> polling, temperature updates may stop coming before the governor drops
> the cooling device states to the "no target" level.
>
> So please test the attached partial revert of the above commit when you can.

Thanks for the quick fix. The partial revert seems to do the trick:

Tested-by: Johan Hovold <johan+linaro@xxxxxxxxxx>

Johan