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[PATCH 3/5] cpufreq/amd-pstate: Refactor amd_pstate_epp_reenable() and amd_pstate_epp_offline()

Dhananjay Ugwekar posted 5 patches 1 year ago
[PATCH 3/5] cpufreq/amd-pstate: Refactor amd_pstate_epp_reenable() and amd_pstate_epp_offline()
Posted by Dhananjay Ugwekar 1 year ago 
Replace similar code chunks with amd_pstate_update_perf() and
amd_pstate_set_epp() function calls.

Signed-off-by: Dhananjay Ugwekar <Dhananjay.Ugwekar@amd.com>
---
 drivers/cpufreq/amd-pstate.c | 36 +++++++-----------------------------
 1 file changed, 7 insertions(+), 29 deletions(-)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index a1b2393cef22..a38be7727c9d 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -1630,25 +1630,17 @@ static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy)
 
 static void amd_pstate_epp_reenable(struct amd_cpudata *cpudata)
 {
-	struct cppc_perf_ctrls perf_ctrls;
-	u64 value, max_perf;
+	u64 max_perf;
 	int ret;
 
 	ret = amd_pstate_cppc_enable(true);
 	if (ret)
 		pr_err("failed to enable amd pstate during resume, return %d\n", ret);
 
-	value = READ_ONCE(cpudata->cppc_req_cached);
 	max_perf = READ_ONCE(cpudata->highest_perf);
 
-	if (cpu_feature_enabled(X86_FEATURE_CPPC)) {
-		wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
-	} else {
-		perf_ctrls.max_perf = max_perf;
-		cppc_set_perf(cpudata->cpu, &perf_ctrls);
-		perf_ctrls.energy_perf = AMD_CPPC_ENERGY_PERF_PREF(cpudata->epp_cached);
-		cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
-	}
+	amd_pstate_update_perf(cpudata, 0, 0, max_perf, false);
+	amd_pstate_set_epp(cpudata, cpudata->epp_cached);
 }
 
 static int amd_pstate_epp_cpu_online(struct cpufreq_policy *policy)
@@ -1668,7 +1660,6 @@ static int amd_pstate_epp_cpu_online(struct cpufreq_policy *policy)
 static void amd_pstate_epp_offline(struct cpufreq_policy *policy)
 {
 	struct amd_cpudata *cpudata = policy->driver_data;
-	struct cppc_perf_ctrls perf_ctrls;
 	int min_perf;
 	u64 value;
 
@@ -1676,23 +1667,10 @@ static void amd_pstate_epp_offline(struct cpufreq_policy *policy)
 	value = READ_ONCE(cpudata->cppc_req_cached);
 
 	mutex_lock(&amd_pstate_limits_lock);
-	if (cpu_feature_enabled(X86_FEATURE_CPPC)) {
-		cpudata->epp_policy = CPUFREQ_POLICY_UNKNOWN;
-
-		/* Set max perf same as min perf */
-		value &= ~AMD_CPPC_MAX_PERF(~0L);
-		value |= AMD_CPPC_MAX_PERF(min_perf);
-		value &= ~AMD_CPPC_MIN_PERF(~0L);
-		value |= AMD_CPPC_MIN_PERF(min_perf);
-		wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
-	} else {
-		perf_ctrls.desired_perf = 0;
-		perf_ctrls.min_perf = min_perf;
-		perf_ctrls.max_perf = min_perf;
-		cppc_set_perf(cpudata->cpu, &perf_ctrls);
-		perf_ctrls.energy_perf = AMD_CPPC_ENERGY_PERF_PREF(HWP_EPP_BALANCE_POWERSAVE);
-		cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
-	}
+
+	amd_pstate_update_perf(cpudata, min_perf, 0, min_perf, false);
+	amd_pstate_set_epp(cpudata, AMD_CPPC_EPP_BALANCE_POWERSAVE);
+
 	mutex_unlock(&amd_pstate_limits_lock);
 }
 
-- 
2.34.1
Re: [PATCH 3/5] cpufreq/amd-pstate: Refactor amd_pstate_epp_reenable() and amd_pstate_epp_offline()
Posted by Gautham R. Shenoy 1 year ago 
On Wed, Dec 04, 2024 at 02:48:40PM +0000, Dhananjay Ugwekar wrote:
> Replace similar code chunks with amd_pstate_update_perf() and
> amd_pstate_set_epp() function calls.
> 
> Signed-off-by: Dhananjay Ugwekar <Dhananjay.Ugwekar@amd.com>
> ---
>  drivers/cpufreq/amd-pstate.c | 36 +++++++-----------------------------
>  1 file changed, 7 insertions(+), 29 deletions(-)
> 
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index a1b2393cef22..a38be7727c9d 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -1630,25 +1630,17 @@ static int amd_pstate_epp_set_policy(struct cpufreq_policy *policy)
>  
>  static void amd_pstate_epp_reenable(struct amd_cpudata *cpudata)
>  {
> -	struct cppc_perf_ctrls perf_ctrls;
> -	u64 value, max_perf;
> +	u64 max_perf;
>  	int ret;
>  
>  	ret = amd_pstate_cppc_enable(true);
>  	if (ret)
>  		pr_err("failed to enable amd pstate during resume, return %d\n", ret);
>  
> -	value = READ_ONCE(cpudata->cppc_req_cached);
>  	max_perf = READ_ONCE(cpudata->highest_perf);
>  
> -	if (cpu_feature_enabled(X86_FEATURE_CPPC)) {
> -		wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
> -	} else {
> -		perf_ctrls.max_perf = max_perf;
> -		cppc_set_perf(cpudata->cpu, &perf_ctrls);
> -		perf_ctrls.energy_perf = AMD_CPPC_ENERGY_PERF_PREF(cpudata->epp_cached);
> -		cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
> -	}
> +	amd_pstate_update_perf(cpudata, 0, 0, max_perf, false);
> +	amd_pstate_set_epp(cpudata, cpudata->epp_cached);

This will cause two MSR writes on MSR based systems.

But then, we don't expect the amd_pstate_epp_reenable() and
amd_pstate_epp_offline() to be called often. Hence it should be ok.

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

--
Thanks and Regards
gautham.




>  }
>  
>  static int amd_pstate_epp_cpu_online(struct cpufreq_policy *policy)
> @@ -1668,7 +1660,6 @@ static int amd_pstate_epp_cpu_online(struct cpufreq_policy *policy)
>  static void amd_pstate_epp_offline(struct cpufreq_policy *policy)
>  {
>  	struct amd_cpudata *cpudata = policy->driver_data;
> -	struct cppc_perf_ctrls perf_ctrls;
>  	int min_perf;
>  	u64 value;
>  
> @@ -1676,23 +1667,10 @@ static void amd_pstate_epp_offline(struct cpufreq_policy *policy)
>  	value = READ_ONCE(cpudata->cppc_req_cached);
>  
>  	mutex_lock(&amd_pstate_limits_lock);
> -	if (cpu_feature_enabled(X86_FEATURE_CPPC)) {
> -		cpudata->epp_policy = CPUFREQ_POLICY_UNKNOWN;
> -
> -		/* Set max perf same as min perf */
> -		value &= ~AMD_CPPC_MAX_PERF(~0L);
> -		value |= AMD_CPPC_MAX_PERF(min_perf);
> -		value &= ~AMD_CPPC_MIN_PERF(~0L);
> -		value |= AMD_CPPC_MIN_PERF(min_perf);
> -		wrmsrl_on_cpu(cpudata->cpu, MSR_AMD_CPPC_REQ, value);
> -	} else {
> -		perf_ctrls.desired_perf = 0;
> -		perf_ctrls.min_perf = min_perf;
> -		perf_ctrls.max_perf = min_perf;
> -		cppc_set_perf(cpudata->cpu, &perf_ctrls);
> -		perf_ctrls.energy_perf = AMD_CPPC_ENERGY_PERF_PREF(HWP_EPP_BALANCE_POWERSAVE);
> -		cppc_set_epp_perf(cpudata->cpu, &perf_ctrls, 1);
> -	}
> +
> +	amd_pstate_update_perf(cpudata, min_perf, 0, min_perf, false);
> +	amd_pstate_set_epp(cpudata, AMD_CPPC_EPP_BALANCE_POWERSAVE);
> +
>  	mutex_unlock(&amd_pstate_limits_lock);
>  }
>  
> -- 
> 2.34.1
>
Re: [PATCH 3/5] cpufreq/amd-pstate: Refactor amd_pstate_epp_reenable() and amd_pstate_epp_offline()
Posted by kernel test robot 1 year ago 
Hi Dhananjay,

kernel test robot noticed the following build warnings:

[auto build test WARNING on rafael-pm/linux-next]
[also build test WARNING on rafael-pm/bleeding-edge linus/master v6.13-rc1 next-20241204]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Dhananjay-Ugwekar/cpufreq-amd-pstate-Convert-the-amd_pstate_get-set_epp-to-static-calls/20241204-225537
base:   https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git linux-next
patch link:    https://lore.kernel.org/r/20241204144842.164178-4-Dhananjay.Ugwekar%40amd.com
patch subject: [PATCH 3/5] cpufreq/amd-pstate: Refactor amd_pstate_epp_reenable() and amd_pstate_epp_offline()
config: x86_64-buildonly-randconfig-006-20241205 (https://download.01.org/0day-ci/archive/20241205/202412050615.ObPzrf34-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241205/202412050615.ObPzrf34-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202412050615.ObPzrf34-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/cpufreq/amd-pstate.c: In function 'amd_pstate_epp_offline':
>> drivers/cpufreq/amd-pstate.c:1664:13: warning: variable 'value' set but not used [-Wunused-but-set-variable]
    1664 |         u64 value;
         |             ^~~~~


vim +/value +1664 drivers/cpufreq/amd-pstate.c

d4da12f8033a123 Perry Yuan        2023-01-31  1659  
d4da12f8033a123 Perry Yuan        2023-01-31  1660  static void amd_pstate_epp_offline(struct cpufreq_policy *policy)
d4da12f8033a123 Perry Yuan        2023-01-31  1661  {
d4da12f8033a123 Perry Yuan        2023-01-31  1662  	struct amd_cpudata *cpudata = policy->driver_data;
d4da12f8033a123 Perry Yuan        2023-01-31  1663  	int min_perf;
d4da12f8033a123 Perry Yuan        2023-01-31 @1664  	u64 value;
d4da12f8033a123 Perry Yuan        2023-01-31  1665  
d4da12f8033a123 Perry Yuan        2023-01-31  1666  	min_perf = READ_ONCE(cpudata->lowest_perf);
d4da12f8033a123 Perry Yuan        2023-01-31  1667  	value = READ_ONCE(cpudata->cppc_req_cached);
d4da12f8033a123 Perry Yuan        2023-01-31  1668  
d4da12f8033a123 Perry Yuan        2023-01-31  1669  	mutex_lock(&amd_pstate_limits_lock);
d4da12f8033a123 Perry Yuan        2023-01-31  1670  
33cc0b550fa3510 Dhananjay Ugwekar 2024-12-04  1671  	amd_pstate_update_perf(cpudata, min_perf, 0, min_perf, false);
33cc0b550fa3510 Dhananjay Ugwekar 2024-12-04  1672  	amd_pstate_set_epp(cpudata, AMD_CPPC_EPP_BALANCE_POWERSAVE);
33cc0b550fa3510 Dhananjay Ugwekar 2024-12-04  1673  
d4da12f8033a123 Perry Yuan        2023-01-31  1674  	mutex_unlock(&amd_pstate_limits_lock);
d4da12f8033a123 Perry Yuan        2023-01-31  1675  }
d4da12f8033a123 Perry Yuan        2023-01-31  1676  

-- 
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