linux-kernel - Re: [PATCH 8/8] cpufreq: amd-pstate: Drop some uses of cpudata->hw

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Message-ID: <Zs4G084+7MmzdYjU@BLRRASHENOY1.amd.com>
Date: Tue, 27 Aug 2024 22:33:15 +0530
From: "Gautham R. Shenoy" <gautham.shenoy@....com>
To: Mario Limonciello <superm1@...nel.org>
Cc: Borislav Petkov <bp@...en8.de>, Perry Yuan <perry.yuan@....com>,
	"maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" <x86@...nel.org>,
	"Rafael J . Wysocki" <rafael@...nel.org>,
	"open list:X86 ARCHITECTURE (32-BIT AND 64-BIT)" <linux-kernel@...r.kernel.org>,
	"open list:ACPI" <linux-acpi@...r.kernel.org>,
	"open list:CPU FREQUENCY SCALING FRAMEWORK" <linux-pm@...r.kernel.org>,
	Mario Limonciello <mario.limonciello@....com>
Subject: Re: [PATCH 8/8] cpufreq: amd-pstate: Drop some uses of
 cpudata->hw_prefcore

On Mon, Aug 26, 2024 at 04:13:58PM -0500, Mario Limonciello wrote:
> From: Mario Limonciello <mario.limonciello@....com>
> 
> As the global variable is cleared when preferred cores is not present
> the local variable use isn't needed in many functions.
> Drop it where possible.  No intended functional changes.
> 
> Signed-off-by: Mario Limonciello <mario.limonciello@....com>
> ---
>  drivers/cpufreq/amd-pstate.c | 7 +------
>  1 file changed, 1 insertion(+), 6 deletions(-)
> 
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index ed05d7a0add10..257e28e549bd1 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -1112,12 +1112,7 @@ static ssize_t show_amd_pstate_prefcore_ranking(struct cpufreq_policy *policy,
>  static ssize_t show_amd_pstate_hw_prefcore(struct cpufreq_policy *policy,
>  					   char *buf)
>  {
> -	bool hw_prefcore;
> -	struct amd_cpudata *cpudata = policy->driver_data;
> -
> -	hw_prefcore = READ_ONCE(cpudata->hw_prefcore);
> -
> -	return sysfs_emit(buf, "%s\n", str_enabled_disabled(hw_prefcore));
> +	return sysfs_emit(buf, "%s\n", str_enabled_disabled(amd_pstate_prefcore));


If the user boots with "amd_prefcore=disable" on a system that
supports preferred-core, pror to this patchset, cpudata->hw_prefcore
would be true and thus, amd_pstate_hw_prefcore would show "enabled".

With this patchset, it would show "disabled". Or am I missing something?



>  }
>  
>  static ssize_t show_energy_performance_available_preferences(
> -- 
> 2.43.0
> 

--
Thanks and Regards
gautham.