2024-02-07 13:11:07

by Tor Vic

Subject: [PATCH][next] cpufreq: amd-pstate: Fix min_perf assignment in amd_pstate_adjust_perf()

In the function amd_pstate_adjust_perf(), the 'min_perf' variable is set
to 'highest_perf' instead of 'lowest_perf'.

Fixes: 1d215f0319c2 ("cpufreq: amd-pstate: Add fast switch function for
AMD P-State")
Reported-by: Oleksandr Natalenko <[email protected]>
Signed-off-by: Tor Vic <[email protected]>
---
IIRC, this was first reported by Oleksandr, hence the 'Reported-by' tag.
---
drivers/cpufreq/amd-pstate.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 08e112444c27..aa5e57e27d2b 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -577,7 +577,7 @@ static void amd_pstate_adjust_perf(unsigned int cpu,
if (target_perf < capacity)
des_perf = DIV_ROUND_UP(cap_perf * target_perf, capacity);

- min_perf = READ_ONCE(cpudata->highest_perf);
+ min_perf = READ_ONCE(cpudata->lowest_perf);
if (_min_perf < capacity)
min_perf = DIV_ROUND_UP(cap_perf * _min_perf, capacity);

--
2.43.0

2024-02-07 13:55:01

by Yuan, Perry

Subject: RE: [PATCH][next] cpufreq: amd-pstate: Fix min_perf assignment in amd_pstate_adjust_perf()

[AMD Official Use Only - General]

Hi Tor,

> -----Original Message-----
> From: Tor Vic <[email protected]>
> Sent: Wednesday, February 7, 2024 9:09 PM
> To: Huang, Ray <[email protected]>; Yuan, Perry
> <[email protected]>; [email protected]
> Cc: Linux Kernel Mailing List <[email protected]>; linux-
> [email protected]; Oleksandr Natalenko <[email protected]>
> Subject: [PATCH][next] cpufreq: amd-pstate: Fix min_perf assignment in
> amd_pstate_adjust_perf()
>
> In the function amd_pstate_adjust_perf(), the 'min_perf' variable is set to
> 'highest_perf' instead of 'lowest_perf'.
>
> Fixes: 1d215f0319c2 ("cpufreq: amd-pstate: Add fast switch function for AMD
> P-State")
> Reported-by: Oleksandr Natalenko <[email protected]>
> Signed-off-by: Tor Vic <[email protected]>
> ---
> IIRC, this was first reported by Oleksandr, hence the 'Reported-by' tag.
> ---
> drivers/cpufreq/amd-pstate.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index 08e112444c27..aa5e57e27d2b 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -577,7 +577,7 @@ static void amd_pstate_adjust_perf(unsigned int cpu,
> if (target_perf < capacity)
> des_perf = DIV_ROUND_UP(cap_perf * target_perf,
> capacity);
>
> - min_perf = READ_ONCE(cpudata->highest_perf);
> + min_perf = READ_ONCE(cpudata->lowest_perf);
> if (_min_perf < capacity)
> min_perf = DIV_ROUND_UP(cap_perf * _min_perf, capacity);
>
> --
> 2.43.0

Thanks for the fix!

Reviewed-by: Perry Yuan <[email protected]>

2024-02-07 14:08:20

by Tor Vic

Subject: Re: [PATCH][next] cpufreq: amd-pstate: Fix min_perf assignment in amd_pstate_adjust_perf()

On 2/7/24 14:54, Yuan, Perry wrote:
> [AMD Official Use Only - General]
>
> Hi Tor,
>
>> -----Original Message-----
>> From: Tor Vic <[email protected]>
>> Sent: Wednesday, February 7, 2024 9:09 PM
>> To: Huang, Ray <[email protected]>; Yuan, Perry
>> <[email protected]>; [email protected]
>> Cc: Linux Kernel Mailing List <[email protected]>; linux-
>> [email protected]; Oleksandr Natalenko <[email protected]>
>> Subject: [PATCH][next] cpufreq: amd-pstate: Fix min_perf assignment in
>> amd_pstate_adjust_perf()
>>
>> In the function amd_pstate_adjust_perf(), the 'min_perf' variable is set to
>> 'highest_perf' instead of 'lowest_perf'.
>>
>> Fixes: 1d215f0319c2 ("cpufreq: amd-pstate: Add fast switch function for AMD
>> P-State")
>> Reported-by: Oleksandr Natalenko <[email protected]>
>> Signed-off-by: Tor Vic <[email protected]>
>> ---
>> IIRC, this was first reported by Oleksandr, hence the 'Reported-by' tag.
>> ---
>> drivers/cpufreq/amd-pstate.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
>> index 08e112444c27..aa5e57e27d2b 100644
>> --- a/drivers/cpufreq/amd-pstate.c
>> +++ b/drivers/cpufreq/amd-pstate.c
>> @@ -577,7 +577,7 @@ static void amd_pstate_adjust_perf(unsigned int cpu,
>> if (target_perf < capacity)
>> des_perf = DIV_ROUND_UP(cap_perf * target_perf,
>> capacity);
>>
>> - min_perf = READ_ONCE(cpudata->highest_perf);
>> + min_perf = READ_ONCE(cpudata->lowest_perf);
>> if (_min_perf < capacity)
>> min_perf = DIV_ROUND_UP(cap_perf * _min_perf, capacity);
>>
>> --
>> 2.43.0
>
> Thanks for the fix!

I think this is actually for stable and mainline too, not only for -next.
Should I resend with 'Cc: stable' tag and your Reviewed-by?

>
> Reviewed-by: Perry Yuan <[email protected]>