Re: [PATCH] cpufreq/amd-pstate: Fix setting scaling max/min freq values

From: Rafael J. Wysocki
Date: Mon Jan 22 2024 - 14:41:10 EST


On Mon, Jan 22, 2024 at 3:57 PM Wyes Karny <wkarny@xxxxxxxxx> wrote:
>
> On Sat, Jan 20, 2024 at 5:49 AM Mario Limonciello
> <mario.limonciello@xxxxxxx> wrote:
> >
> > Scaling min/max freq values were being cached and lagging a setting
> > each time. Fix the ordering of the clamp call to ensure they work.
> >
> > Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217931
> > Cc: stable@xxxxxxxxxxxxxxx
> > Cc: wkarny@xxxxxxxxx
> > Fixes: febab20caeba ("cpufreq/amd-pstate: Fix scaling_min_freq and scaling_max_freq update")
> > Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
>
> Reviewed-by: Wyes Karny <wkarny@xxxxxxxxx>
>
> > ---
> > drivers/cpufreq/amd-pstate.c | 7 +++----
> > 1 file changed, 3 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> > index 1f6186475715..1791d37fbc53 100644
> > --- a/drivers/cpufreq/amd-pstate.c
> > +++ b/drivers/cpufreq/amd-pstate.c
> > @@ -1232,14 +1232,13 @@ static void amd_pstate_epp_update_limit(struct cpufreq_policy *policy)
> > max_limit_perf = div_u64(policy->max * cpudata->highest_perf, cpudata->max_freq);
> > min_limit_perf = div_u64(policy->min * cpudata->highest_perf, cpudata->max_freq);
> >
> > + WRITE_ONCE(cpudata->max_limit_perf, max_limit_perf);
> > + WRITE_ONCE(cpudata->min_limit_perf, min_limit_perf);
> > +
> > max_perf = clamp_t(unsigned long, max_perf, cpudata->min_limit_perf,
> > cpudata->max_limit_perf);
> > min_perf = clamp_t(unsigned long, min_perf, cpudata->min_limit_perf,
> > cpudata->max_limit_perf);
> > -
> > - WRITE_ONCE(cpudata->max_limit_perf, max_limit_perf);
> > - WRITE_ONCE(cpudata->min_limit_perf, min_limit_perf);
> > -
> > value = READ_ONCE(cpudata->cppc_req_cached);
> >
> > if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE)
> > --

Applied as 6.8-rc material, thanks!