Re: [PATCH 11/15] cpufreq/amd-pstate: Cache EPP value and use that everywhere

From: Gautham R. Shenoy
Date: Fri Dec 06 2024 - 11:18:32 EST


Hello Mario,

On Thu, Dec 05, 2024 at 04:28:43PM -0600, Mario Limonciello wrote:
> Cache the value in cpudata->epp_cached, and use that for all callers.
> As all callers use cached value merge amd_pstate_get_energy_pref_index()
> into show_energy_performance_preference().
>
> Check if the EPP value is changed before writing it to MSR or
> shared memory region.

The patch looks ok to me. Just one comment below:

[..snip..]

> @@ -1610,6 +1591,8 @@ static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy)
>
> cpudata->policy = policy->policy;
>
> + guard(mutex)(&amd_pstate_limits_lock);
> +

Shouldn't this hunk be a different patch. The changelog doesn't say
anything about making amd_pstate_epp_update_limit() call while holding
the amd_pstate_limits_lock.


> ret = amd_pstate_epp_update_limit(policy);
> if (ret)
> return ret;
> --
> 2.43.0
>

For the rest of the patch

Reviewed-by: Gautham R. Shenoy <gautham.shenoy@xxxxxxx>

--
Thanks and Regards
gautham.