[PATCH 0/3] cpufreq: CPPC: Some optimizations for cppc_cpufreq.c.

[PATCH 0/3] cpufreq: CPPC: Some optimizations for cppc_cpufreq.c.

[Lifeng Zheng]

This patch series makes some minor optimizations for cppc_cpufreq.c to
makes codes cleaner.

Lifeng Zheng (3):
  cpufreq: CPPC: Remove cpu_data_list
  cpufreq: CPPC: Return void in populate_efficiency_class()
  cpufreq: CPPC: Remove forward declaration of
    cppc_cpufreq_register_em()

 drivers/cpufreq/cppc_cpufreq.c | 59 +++++++++-------------------------
 include/acpi/cppc_acpi.h       |  1 -
 2 files changed, 15 insertions(+), 45 deletions(-)

-- 
2.33.0

[PATCH 1/3] cpufreq: CPPC: Remove cpu_data_list

[Lifeng Zheng]

After commit a28b2bfc099c ("cppc_cpufreq: replace per-cpu data array with a
list"), cpu_data can be got from policy->driver_data, so cpu_data_list is
not actually needed and can be removed.

Signed-off-by: Lifeng Zheng <zhenglifeng1@huawei.com>
---
 drivers/cpufreq/cppc_cpufreq.c | 25 -------------------------
 include/acpi/cppc_acpi.h       |  1 -
 2 files changed, 26 deletions(-)

diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
index b7c688a5659c..f3b5ea9fcbf5 100644
--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -26,14 +26,6 @@
 
 #include <acpi/cppc_acpi.h>
 
-/*
- * This list contains information parsed from per CPU ACPI _CPC and _PSD
- * structures: e.g. the highest and lowest supported performance, capabilities,
- * desired performance, level requested etc. Depending on the share_type, not
- * all CPUs will have an entry in the list.
- */
-static LIST_HEAD(cpu_data_list);
-
 static struct cpufreq_driver cppc_cpufreq_driver;
 
 #ifdef CONFIG_ACPI_CPPC_CPUFREQ_FIE
@@ -567,8 +559,6 @@ static struct cppc_cpudata *cppc_cpufreq_get_cpu_data(unsigned int cpu)
 		goto free_mask;
 	}
 
-	list_add(&cpu_data->node, &cpu_data_list);
-
 	return cpu_data;
 
 free_mask:
@@ -583,7 +573,6 @@ static void cppc_cpufreq_put_cpu_data(struct cpufreq_policy *policy)
 {
 	struct cppc_cpudata *cpu_data = policy->driver_data;
 
-	list_del(&cpu_data->node);
 	free_cpumask_var(cpu_data->shared_cpu_map);
 	kfree(cpu_data);
 	policy->driver_data = NULL;
@@ -954,24 +943,10 @@ static int __init cppc_cpufreq_init(void)
 	return ret;
 }
 
-static inline void free_cpu_data(void)
-{
-	struct cppc_cpudata *iter, *tmp;
-
-	list_for_each_entry_safe(iter, tmp, &cpu_data_list, node) {
-		free_cpumask_var(iter->shared_cpu_map);
-		list_del(&iter->node);
-		kfree(iter);
-	}
-
-}
-
 static void __exit cppc_cpufreq_exit(void)
 {
 	cpufreq_unregister_driver(&cppc_cpufreq_driver);
 	cppc_freq_invariance_exit();
-
-	free_cpu_data();
 }
 
 module_exit(cppc_cpufreq_exit);
diff --git a/include/acpi/cppc_acpi.h b/include/acpi/cppc_acpi.h
index 325e9543e08f..20f3d62e7a16 100644
--- a/include/acpi/cppc_acpi.h
+++ b/include/acpi/cppc_acpi.h
@@ -139,7 +139,6 @@ struct cppc_perf_fb_ctrs {
 
 /* Per CPU container for runtime CPPC management. */
 struct cppc_cpudata {
-	struct list_head node;
 	struct cppc_perf_caps perf_caps;
 	struct cppc_perf_ctrls perf_ctrls;
 	struct cppc_perf_fb_ctrs perf_fb_ctrs;
-- 
2.33.0

[PATCH 2/3] cpufreq: CPPC: Return void in populate_efficiency_class()

[Lifeng Zheng]

The return value of populate_efficiency_class() is never needed and the
result of it doesn't affect the initialization of cppc_cpufreq. It makes
more sense to have it return void.

Signed-off-by: Lifeng Zheng <zhenglifeng1@huawei.com>
---
 drivers/cpufreq/cppc_cpufreq.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
index f3b5ea9fcbf5..c2be4b188a23 100644
--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -480,7 +480,7 @@ static int cppc_get_cpu_cost(struct device *cpu_dev, unsigned long KHz,
 	return 0;
 }
 
-static int populate_efficiency_class(void)
+static void populate_efficiency_class(void)
 {
 	struct acpi_madt_generic_interrupt *gicc;
 	DECLARE_BITMAP(used_classes, 256) = {};
@@ -495,7 +495,7 @@ static int populate_efficiency_class(void)
 	if (bitmap_weight(used_classes, 256) <= 1) {
 		pr_debug("Efficiency classes are all equal (=%d). "
 			"No EM registered", class);
-		return -EINVAL;
+		return;
 	}
 
 	/*
@@ -512,8 +512,6 @@ static int populate_efficiency_class(void)
 		index++;
 	}
 	cppc_cpufreq_driver.register_em = cppc_cpufreq_register_em;
-
-	return 0;
 }
 
 static void cppc_cpufreq_register_em(struct cpufreq_policy *policy)
@@ -529,9 +527,8 @@ static void cppc_cpufreq_register_em(struct cpufreq_policy *policy)
 }
 
 #else
-static int populate_efficiency_class(void)
+static void populate_efficiency_class(void)
 {
-	return 0;
 }
 #endif
 
-- 
2.33.0

[PATCH 3/3] cpufreq: CPPC: Remove forward declaration of cppc_cpufreq_register_em()

[Lifeng Zheng]

cppc_cpufreq_register_em() is only used in populate_efficiency_class(). A
forward declaration is not necessary. Move cppc_cpufreq_register_em() in
front of populate_efficiency_class() and remove the forward declaration of
cppc_cpufreq_register_em().

No functional change.

Signed-off-by: Lifeng Zheng <zhenglifeng1@huawei.com>
---
 drivers/cpufreq/cppc_cpufreq.c | 25 ++++++++++++-------------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/drivers/cpufreq/cppc_cpufreq.c b/drivers/cpufreq/cppc_cpufreq.c
index c2be4b188a23..a1fd0ff22bc5 100644
--- a/drivers/cpufreq/cppc_cpufreq.c
+++ b/drivers/cpufreq/cppc_cpufreq.c
@@ -344,7 +344,6 @@ static unsigned int cppc_cpufreq_get_transition_delay_us(unsigned int cpu)
 #if defined(CONFIG_ARM64) && defined(CONFIG_ENERGY_MODEL)
 
 static DEFINE_PER_CPU(unsigned int, efficiency_class);
-static void cppc_cpufreq_register_em(struct cpufreq_policy *policy);
 
 /* Create an artificial performance state every CPPC_EM_CAP_STEP capacity unit. */
 #define CPPC_EM_CAP_STEP	(20)
@@ -480,6 +479,18 @@ static int cppc_get_cpu_cost(struct device *cpu_dev, unsigned long KHz,
 	return 0;
 }
 
+static void cppc_cpufreq_register_em(struct cpufreq_policy *policy)
+{
+	struct cppc_cpudata *cpu_data;
+	struct em_data_callback em_cb =
+		EM_ADV_DATA_CB(cppc_get_cpu_power, cppc_get_cpu_cost);
+
+	cpu_data = policy->driver_data;
+	em_dev_register_perf_domain(get_cpu_device(policy->cpu),
+			get_perf_level_count(policy), &em_cb,
+			cpu_data->shared_cpu_map, 0);
+}
+
 static void populate_efficiency_class(void)
 {
 	struct acpi_madt_generic_interrupt *gicc;
@@ -514,18 +525,6 @@ static void populate_efficiency_class(void)
 	cppc_cpufreq_driver.register_em = cppc_cpufreq_register_em;
 }
 
-static void cppc_cpufreq_register_em(struct cpufreq_policy *policy)
-{
-	struct cppc_cpudata *cpu_data;
-	struct em_data_callback em_cb =
-		EM_ADV_DATA_CB(cppc_get_cpu_power, cppc_get_cpu_cost);
-
-	cpu_data = policy->driver_data;
-	em_dev_register_perf_domain(get_cpu_device(policy->cpu),
-			get_perf_level_count(policy), &em_cb,
-			cpu_data->shared_cpu_map, 0);
-}
-
 #else
 static void populate_efficiency_class(void)
 {
-- 
2.33.0

Re: [PATCH 0/3] cpufreq: CPPC: Some optimizations for cppc_cpufreq.c.

[Pierre Gondois]

Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>

On 5/26/25 13:30, Lifeng Zheng wrote:
> This patch series makes some minor optimizations for cppc_cpufreq.c to
> makes codes cleaner.
>
> Lifeng Zheng (3):
>    cpufreq: CPPC: Remove cpu_data_list
>    cpufreq: CPPC: Return void in populate_efficiency_class()
>    cpufreq: CPPC: Remove forward declaration of
>      cppc_cpufreq_register_em()
>
>   drivers/cpufreq/cppc_cpufreq.c | 59 +++++++++-------------------------
>   include/acpi/cppc_acpi.h       |  1 -
>   2 files changed, 15 insertions(+), 45 deletions(-)
>

Re: [PATCH 0/3] cpufreq: CPPC: Some optimizations for cppc_cpufreq.c.

[zhenglifeng (A)]

On 2025/5/28 21:26, Pierre Gondois wrote:

> Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>

Thanks!

> 
> On 5/26/25 13:30, Lifeng Zheng wrote:
>> This patch series makes some minor optimizations for cppc_cpufreq.c to
>> makes codes cleaner.
>>
>> Lifeng Zheng (3):
>>    cpufreq: CPPC: Remove cpu_data_list
>>    cpufreq: CPPC: Return void in populate_efficiency_class()
>>    cpufreq: CPPC: Remove forward declaration of
>>      cppc_cpufreq_register_em()
>>
>>   drivers/cpufreq/cppc_cpufreq.c | 59 +++++++++-------------------------
>>   include/acpi/cppc_acpi.h       |  1 -
>>   2 files changed, 15 insertions(+), 45 deletions(-)
>>

Re: [PATCH 0/3] cpufreq: CPPC: Some optimizations for cppc_cpufreq.c.

[zhenglifeng (A)]

Gentle ping.

On 2025/5/26 19:30, Lifeng Zheng wrote:
> This patch series makes some minor optimizations for cppc_cpufreq.c to
> makes codes cleaner.
> 
> Lifeng Zheng (3):
>   cpufreq: CPPC: Remove cpu_data_list
>   cpufreq: CPPC: Return void in populate_efficiency_class()
>   cpufreq: CPPC: Remove forward declaration of
>     cppc_cpufreq_register_em()
> 
>  drivers/cpufreq/cppc_cpufreq.c | 59 +++++++++-------------------------
>  include/acpi/cppc_acpi.h       |  1 -
>  2 files changed, 15 insertions(+), 45 deletions(-)
> 

Re: [PATCH 0/3] cpufreq: CPPC: Some optimizations for cppc_cpufreq.c.

[Rafael J. Wysocki]

On Tue, Jun 17, 2025 at 4:33 AM zhenglifeng (A) <zhenglifeng1@huawei.com> wrote:
>
> Gentle ping.
>
> On 2025/5/26 19:30, Lifeng Zheng wrote:
> > This patch series makes some minor optimizations for cppc_cpufreq.c to
> > makes codes cleaner.
> >
> > Lifeng Zheng (3):
> >   cpufreq: CPPC: Remove cpu_data_list
> >   cpufreq: CPPC: Return void in populate_efficiency_class()
> >   cpufreq: CPPC: Remove forward declaration of
> >     cppc_cpufreq_register_em()
> >
> >  drivers/cpufreq/cppc_cpufreq.c | 59 +++++++++-------------------------
> >  include/acpi/cppc_acpi.h       |  1 -
> >  2 files changed, 15 insertions(+), 45 deletions(-)

I've started to process this because it has been sent to linux-acpi
and then I realized that Viresh should take it, but since I've applied
it already, I may as well queue it up for 6.17.

Viresh, please let me know if you have any concerns about it.

Thanks!

Re: [PATCH 0/3] cpufreq: CPPC: Some optimizations for cppc_cpufreq.c.

[Viresh Kumar]

On 18-06-25, 21:06, Rafael J. Wysocki wrote:
> On Tue, Jun 17, 2025 at 4:33 AM zhenglifeng (A) <zhenglifeng1@huawei.com> wrote:
> >
> > Gentle ping.
> >
> > On 2025/5/26 19:30, Lifeng Zheng wrote:
> > > This patch series makes some minor optimizations for cppc_cpufreq.c to
> > > makes codes cleaner.
> > >
> > > Lifeng Zheng (3):
> > >   cpufreq: CPPC: Remove cpu_data_list
> > >   cpufreq: CPPC: Return void in populate_efficiency_class()
> > >   cpufreq: CPPC: Remove forward declaration of
> > >     cppc_cpufreq_register_em()
> > >
> > >  drivers/cpufreq/cppc_cpufreq.c | 59 +++++++++-------------------------
> > >  include/acpi/cppc_acpi.h       |  1 -
> > >  2 files changed, 15 insertions(+), 45 deletions(-)
> 
> I've started to process this because it has been sent to linux-acpi
> and then I realized that Viresh should take it, but since I've applied
> it already, I may as well queue it up for 6.17.
> 
> Viresh, please let me know if you have any concerns about it.

I applied this before I saw your email.. Please keep it, I will drop it. Thanks.

-- 
viresh

Re: [PATCH 0/3] cpufreq: CPPC: Some optimizations for cppc_cpufreq.c.

[Viresh Kumar]

On 26-05-25, 19:30, Lifeng Zheng wrote:
> This patch series makes some minor optimizations for cppc_cpufreq.c to
> makes codes cleaner.
> 
> Lifeng Zheng (3):
>   cpufreq: CPPC: Remove cpu_data_list
>   cpufreq: CPPC: Return void in populate_efficiency_class()
>   cpufreq: CPPC: Remove forward declaration of
>     cppc_cpufreq_register_em()
> 
>  drivers/cpufreq/cppc_cpufreq.c | 59 +++++++++-------------------------
>  include/acpi/cppc_acpi.h       |  1 -
>  2 files changed, 15 insertions(+), 45 deletions(-)

Applied. Thanks.

-- 
viresh