linux-kernel - Re: [PATCH 4/4] cpufreq/amd-pstate: Drop needless EPP initialization

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <Zw+WXSoSiFzrUDT5@BLRRASHENOY1.amd.com>
Date: Wed, 16 Oct 2024 16:03:01 +0530
From: "Gautham R. Shenoy" <gautham.shenoy@....com>
To: Mario Limonciello <mario.limonciello@....com>
Cc: Perry Yuan <perry.yuan@....com>, linux-kernel@...r.kernel.org,
	linux-pm@...r.kernel.org,
	Dhananjay Ugwekar <Dhananjay.Ugwekar@....com>
Subject: Re: [PATCH 4/4] cpufreq/amd-pstate: Drop needless EPP initialization

On Sat, Oct 12, 2024 at 12:45:19PM -0500, Mario Limonciello wrote:
> The EPP value doesn't need to be cached to the CPPC request in
> amd_pstate_epp_update_limit() because it's passed as an argument
> at the end to amd_pstate_set_epp() and stored at that time.
> 
> Signed-off-by: Mario Limonciello <mario.limonciello@....com>

Thanks for cleaning it up.

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

--
Thanks and Regards
gautham.

> ---
>  drivers/cpufreq/amd-pstate.c | 6 ------
>  1 file changed, 6 deletions(-)
> 
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index 8d2541f2c74b..90868c8b214e 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -1528,12 +1528,6 @@ static int amd_pstate_epp_update_limit(struct cpufreq_policy *policy)
>  	if (cpudata->policy == CPUFREQ_POLICY_PERFORMANCE)
>  		epp = 0;
>  
> -	/* Set initial EPP value */
> -	if (cpu_feature_enabled(X86_FEATURE_CPPC)) {
> -		value &= ~GENMASK_ULL(31, 24);
> -		value |= (u64)epp << 24;
> -	}
> -
>  	WRITE_ONCE(cpudata->cppc_req_cached, value);
>  	return amd_pstate_set_epp(cpudata, epp);
>  }
> -- 
> 2.43.0
>