diff mbox series

[3/6] cpufreq:amd-pstate: initialize nominal_freq of each cpudata

Message ID 5d5822a829045c02a37d6dac81756be1312a1ac5.1706690577.git.perry.yuan@amd.com
State New
Headers
Series AMD Pstate Fixes And Enhancements |

Commit Message

Yuan, Perry Jan. 31, 2024, 8:50 a.m. UTC 
  Optimizes the process of retrieving the nominal frequency by utilizing
'cpudata->nominal_freq' instead of repeatedly accessing the cppc_acpi interface.

To enhance efficiency and reduce the CPU load, shifted to using
'cpudata->nominal_freq'. It allows for the nominal frequency to be accessed
directly from the cached data in 'cpudata' of each CPU.
It will also slightly reduce the frequency change latency while using pstate
driver passive mode.

Signed-off-by: Perry Yuan <perry.yuan@amd.com>
---
 drivers/cpufreq/amd-pstate.c | 26 ++++++++++++++------------
 1 file changed, 14 insertions(+), 12 deletions(-)

Comments

Mario Limonciello Jan. 31, 2024, 9:47 p.m. UTC | #1 
On 1/31/2024 02:50, Perry Yuan wrote:
> Optimizes the process of retrieving the nominal frequency by utilizing
> 'cpudata->nominal_freq' instead of repeatedly accessing the cppc_acpi interface.
> 
> To enhance efficiency and reduce the CPU load, shifted to using
> 'cpudata->nominal_freq'. It allows for the nominal frequency to be accessed
> directly from the cached data in 'cpudata' of each CPU.
> It will also slightly reduce the frequency change latency while using pstate
> driver passive mode.
> 
> Signed-off-by: Perry Yuan <perry.yuan@amd.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
> ---
>   drivers/cpufreq/amd-pstate.c | 26 ++++++++++++++------------
>   1 file changed, 14 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
> index 9291a22bd3cc..db7b36afdce2 100644
> --- a/drivers/cpufreq/amd-pstate.c
> +++ b/drivers/cpufreq/amd-pstate.c
> @@ -600,7 +600,7 @@ static int amd_get_max_freq(struct amd_cpudata *cpudata)
>   	if (ret)
>   		return ret;
>   
> -	nominal_freq = cppc_perf.nominal_freq;
> +	nominal_freq = READ_ONCE(cpudata->nominal_freq);
>   	nominal_perf = READ_ONCE(cpudata->nominal_perf);
>   	max_perf = READ_ONCE(cpudata->highest_perf);
>   
> @@ -639,7 +639,7 @@ static int amd_get_lowest_nonlinear_freq(struct amd_cpudata *cpudata)
>   	if (ret)
>   		return ret;
>   
> -	nominal_freq = cppc_perf.nominal_freq;
> +	nominal_freq = READ_ONCE(cpudata->nominal_freq);
>   	nominal_perf = READ_ONCE(cpudata->nominal_perf);
>   
>   	lowest_nonlinear_perf = cppc_perf.lowest_nonlinear_perf;
> @@ -712,13 +712,15 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy)
>   	amd_pstate_boost_init(cpudata);
>   
>   	min_freq = amd_get_min_freq(cpudata);
> -	max_freq = amd_get_max_freq(cpudata);
>   	nominal_freq = amd_get_nominal_freq(cpudata);
> +	cpudata->nominal_freq = nominal_freq;
> +	max_freq = amd_get_max_freq(cpudata);
>   	lowest_nonlinear_freq = amd_get_lowest_nonlinear_freq(cpudata);
>   
> -	if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) {
> -		dev_err(dev, "min_freq(%d) or max_freq(%d) value is incorrect\n",
> -			min_freq, max_freq);
> +	if (min_freq < 0 || max_freq < 0 || min_freq > max_freq || nominal_freq == 0) {
> +		dev_err(dev, "min_freq(%d) or max_freq(%d) or nominal_freq(%d)	\
> +			value is incorrect\n",	\
> +			min_freq, max_freq, nominal_freq);
>   		ret = -EINVAL;
>   		goto free_cpudata1;
>   	}
> @@ -755,7 +757,6 @@ static int amd_pstate_cpu_init(struct cpufreq_policy *policy)
>   	/* Initial processor data capability frequencies */
>   	cpudata->max_freq = max_freq;
>   	cpudata->min_freq = min_freq;
> -	cpudata->nominal_freq = nominal_freq;
>   	cpudata->lowest_nonlinear_freq = lowest_nonlinear_freq;
>   
>   	policy->driver_data = cpudata;
> @@ -1266,12 +1267,14 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
>   	amd_pstate_boost_init(cpudata);
>   
>   	min_freq = amd_get_min_freq(cpudata);
> -	max_freq = amd_get_max_freq(cpudata);
>   	nominal_freq = amd_get_nominal_freq(cpudata);
> +	cpudata->nominal_freq = nominal_freq;
> +	max_freq = amd_get_max_freq(cpudata);
>   	lowest_nonlinear_freq = amd_get_lowest_nonlinear_freq(cpudata);
> -	if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) {
> -		dev_err(dev, "min_freq(%d) or max_freq(%d) value is incorrect\n",
> -				min_freq, max_freq);
> +	if (min_freq < 0 || max_freq < 0 || min_freq > max_freq || nominal_freq == 0) {
> +		dev_err(dev, "min_freq(%d) or max_freq(%d) or nominal_freq(%d)	\
> +				value is incorrect\n",	\
> +				min_freq, max_freq, nominal_freq);
>   		ret = -EINVAL;
>   		goto free_cpudata1;
>   	}
> @@ -1284,7 +1287,6 @@ static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
>   	/* Initial processor data capability frequencies */
>   	cpudata->max_freq = max_freq;
>   	cpudata->min_freq = min_freq;
> -	cpudata->nominal_freq = nominal_freq;
>   	cpudata->lowest_nonlinear_freq = lowest_nonlinear_freq;
>   
>   	policy->driver_data = cpudata;
diff mbox series

Patch

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index 9291a22bd3cc..db7b36afdce2 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -600,7 +600,7 @@  static int amd_get_max_freq(struct amd_cpudata *cpudata)
 	if (ret)
 		return ret;
 
-	nominal_freq = cppc_perf.nominal_freq;
+	nominal_freq = READ_ONCE(cpudata->nominal_freq);
 	nominal_perf = READ_ONCE(cpudata->nominal_perf);
 	max_perf = READ_ONCE(cpudata->highest_perf);
 
@@ -639,7 +639,7 @@  static int amd_get_lowest_nonlinear_freq(struct amd_cpudata *cpudata)
 	if (ret)
 		return ret;
 
-	nominal_freq = cppc_perf.nominal_freq;
+	nominal_freq = READ_ONCE(cpudata->nominal_freq);
 	nominal_perf = READ_ONCE(cpudata->nominal_perf);
 
 	lowest_nonlinear_perf = cppc_perf.lowest_nonlinear_perf;
@@ -712,13 +712,15 @@  static int amd_pstate_cpu_init(struct cpufreq_policy *policy)
 	amd_pstate_boost_init(cpudata);
 
 	min_freq = amd_get_min_freq(cpudata);
-	max_freq = amd_get_max_freq(cpudata);
 	nominal_freq = amd_get_nominal_freq(cpudata);
+	cpudata->nominal_freq = nominal_freq;
+	max_freq = amd_get_max_freq(cpudata);
 	lowest_nonlinear_freq = amd_get_lowest_nonlinear_freq(cpudata);
 
-	if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) {
-		dev_err(dev, "min_freq(%d) or max_freq(%d) value is incorrect\n",
-			min_freq, max_freq);
+	if (min_freq < 0 || max_freq < 0 || min_freq > max_freq || nominal_freq == 0) {
+		dev_err(dev, "min_freq(%d) or max_freq(%d) or nominal_freq(%d)	\
+			value is incorrect\n",	\
+			min_freq, max_freq, nominal_freq);
 		ret = -EINVAL;
 		goto free_cpudata1;
 	}
@@ -755,7 +757,6 @@  static int amd_pstate_cpu_init(struct cpufreq_policy *policy)
 	/* Initial processor data capability frequencies */
 	cpudata->max_freq = max_freq;
 	cpudata->min_freq = min_freq;
-	cpudata->nominal_freq = nominal_freq;
 	cpudata->lowest_nonlinear_freq = lowest_nonlinear_freq;
 
 	policy->driver_data = cpudata;
@@ -1266,12 +1267,14 @@  static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
 	amd_pstate_boost_init(cpudata);
 
 	min_freq = amd_get_min_freq(cpudata);
-	max_freq = amd_get_max_freq(cpudata);
 	nominal_freq = amd_get_nominal_freq(cpudata);
+	cpudata->nominal_freq = nominal_freq;
+	max_freq = amd_get_max_freq(cpudata);
 	lowest_nonlinear_freq = amd_get_lowest_nonlinear_freq(cpudata);
-	if (min_freq < 0 || max_freq < 0 || min_freq > max_freq) {
-		dev_err(dev, "min_freq(%d) or max_freq(%d) value is incorrect\n",
-				min_freq, max_freq);
+	if (min_freq < 0 || max_freq < 0 || min_freq > max_freq || nominal_freq == 0) {
+		dev_err(dev, "min_freq(%d) or max_freq(%d) or nominal_freq(%d)	\
+				value is incorrect\n",	\
+				min_freq, max_freq, nominal_freq);
 		ret = -EINVAL;
 		goto free_cpudata1;
 	}
@@ -1284,7 +1287,6 @@  static int amd_pstate_epp_cpu_init(struct cpufreq_policy *policy)
 	/* Initial processor data capability frequencies */
 	cpudata->max_freq = max_freq;
 	cpudata->min_freq = min_freq;
-	cpudata->nominal_freq = nominal_freq;
 	cpudata->lowest_nonlinear_freq = lowest_nonlinear_freq;
 
 	policy->driver_data = cpudata;