Re: [PATCH v4 07/13] cpufreq: amd_pstate: map desired perf into pstate scope for powersave governor

Huang Rui
2022-07-19T00:56:49Z

On Fri, Jul 15, 2022 at 06:04:26PM +0800, Yuan, Perry wrote:
> The patch will fix the invalid desired perf value for powersave
> governor. This issue is found when testing on one AMD EPYC system, the
> actual des_perf is smaller than the min_perf value, that is invalid
> value. because the min_perf is the lowest_perf system can support in
> idle state.
>
> Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>

Reviewed-by: Huang Rui <ray.huang@amd.com>

> ---
> drivers/cpufreq/amd-pstate.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index 4b764870035e..ebc7c6d389be 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -268,6 +268,7 @@ static void amd_pstate_update(struct amd_cpudata *cpudata, u32 min_perf,
> u64 prev = READ_ONCE(cpudata->cppc_req_cached);
> u64 value = prev;
>
> + des_perf = clamp_t(unsigned long, des_perf, min_perf, max_perf);
> value &= ~AMD_CPPC_MIN_PERF(~0L);
> value |= AMD_CPPC_MIN_PERF(min_perf);
>
> @@ -356,8 +357,6 @@ static void amd_pstate_adjust_perf(unsigned int cpu,
> if (max_perf < min_perf)
> max_perf = min_perf;
>
> - des_perf = clamp_t(unsigned long, des_perf, min_perf, max_perf);
> -
> amd_pstate_update(cpudata, min_perf, des_perf, max_perf, true);
> }
>
> --
> 2.32.0
>