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[PATCH v2] ACPI: processor: Move arch_init_invariance_cppc() call later

Mario Limonciello posted 1 patch 3 weeks, 1 day ago
There is a newer version of this series
arch/x86/include/asm/topology.h | 2 ++
drivers/acpi/cppc_acpi.c        | 6 ------
drivers/acpi/processor_driver.c | 1 +
3 files changed, 3 insertions(+), 6 deletions(-)
[PATCH v2] ACPI: processor: Move arch_init_invariance_cppc() call later
Posted by Mario Limonciello 3 weeks, 1 day ago 
From: Mario Limonciello <mario.limonciello@amd.com>

arch_init_invariance_cppc() is called at the end of
acpi_cppc_processor_probe() in order to configure frequency invariance
based upon the values from _CPC.

This however doesn't work on AMD CPPC shared memory designs that have
AMD preferred cores enabled because _CPC needs to be analyzed from all
cores to judge if preferred cores are enabled.

This issue manifests to users as a warning since commit 21fb59ab4b97
("ACPI: CPPC: Adjust debug messages in amd_set_max_freq_ratio() to warn"):
```
Could not retrieve highest performance (-19)
```

However the warning isn't the cause of this, it was actually
commit 279f838a61f9 ("x86/amd: Detect preferred cores in
amd_get_boost_ratio_numerator()") which exposed the issue.

To fix this problem, push the call to the arch_init_invariance_cppc()
macro to the end of acpi_processor_driver_init().

Fixes: 279f838a61f9 ("x86/amd: Detect preferred cores in amd_get_boost_ratio_numerator()")
Reported-by: Ivan Shapovalov <intelfx@intelfx.name>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219431
Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
v1->v2:
 * Fix LKP robot issue when CONFIG_ACPI_CPPC_LIB not defined
---
 arch/x86/include/asm/topology.h | 2 ++
 drivers/acpi/cppc_acpi.c        | 6 ------
 drivers/acpi/processor_driver.c | 1 +
 3 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index abe3a8f22cbd..b04c5db7e945 100644
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -295,6 +295,8 @@ extern void arch_scale_freq_tick(void);
 #ifdef CONFIG_ACPI_CPPC_LIB
 void init_freq_invariance_cppc(void);
 #define arch_init_invariance_cppc init_freq_invariance_cppc
+#else
+static inline void arch_init_invariance_cppc(void) { }
 #endif
 
 #endif /* _ASM_X86_TOPOLOGY_H */
diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
index ed91dfd4fdca..9d48cd706659 100644
--- a/drivers/acpi/cppc_acpi.c
+++ b/drivers/acpi/cppc_acpi.c
@@ -671,10 +671,6 @@ static int pcc_data_alloc(int pcc_ss_id)
  *  )
  */
 
-#ifndef arch_init_invariance_cppc
-static inline void arch_init_invariance_cppc(void) { }
-#endif
-
 /**
  * acpi_cppc_processor_probe - Search for per CPU _CPC objects.
  * @pr: Ptr to acpi_processor containing this CPU's logical ID.
@@ -905,8 +901,6 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
 		goto out_free;
 	}
 
-	arch_init_invariance_cppc();
-
 	kfree(output.pointer);
 	return 0;
 
diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
index cb52dd000b95..59620e7bc664 100644
--- a/drivers/acpi/processor_driver.c
+++ b/drivers/acpi/processor_driver.c
@@ -270,6 +270,7 @@ static int __init acpi_processor_driver_init(void)
 				  NULL, acpi_soft_cpu_dead);
 
 	acpi_processor_throttling_init();
+	arch_init_invariance_cppc();
 	return 0;
 err:
 	driver_unregister(&acpi_processor_driver);
-- 
2.43.0
Re: [PATCH v2] ACPI: processor: Move arch_init_invariance_cppc() call later
Posted by Rafael J. Wysocki 2 weeks, 6 days ago 
On Sat, Nov 2, 2024 at 4:24 AM Mario Limonciello <superm1@kernel.org> wrote:
>
> From: Mario Limonciello <mario.limonciello@amd.com>
>
> arch_init_invariance_cppc() is called at the end of
> acpi_cppc_processor_probe() in order to configure frequency invariance
> based upon the values from _CPC.
>
> This however doesn't work on AMD CPPC shared memory designs that have
> AMD preferred cores enabled because _CPC needs to be analyzed from all
> cores to judge if preferred cores are enabled.
>
> This issue manifests to users as a warning since commit 21fb59ab4b97
> ("ACPI: CPPC: Adjust debug messages in amd_set_max_freq_ratio() to warn"):
> ```
> Could not retrieve highest performance (-19)
> ```
>
> However the warning isn't the cause of this, it was actually
> commit 279f838a61f9 ("x86/amd: Detect preferred cores in
> amd_get_boost_ratio_numerator()") which exposed the issue.
>
> To fix this problem, push the call to the arch_init_invariance_cppc()
> macro to the end of acpi_processor_driver_init().
>
> Fixes: 279f838a61f9 ("x86/amd: Detect preferred cores in amd_get_boost_ratio_numerator()")
> Reported-by: Ivan Shapovalov <intelfx@intelfx.name>
> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219431
> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
> ---
> v1->v2:
>  * Fix LKP robot issue when CONFIG_ACPI_CPPC_LIB not defined
> ---
>  arch/x86/include/asm/topology.h | 2 ++
>  drivers/acpi/cppc_acpi.c        | 6 ------
>  drivers/acpi/processor_driver.c | 1 +
>  3 files changed, 3 insertions(+), 6 deletions(-)
>
> diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
> index abe3a8f22cbd..b04c5db7e945 100644
> --- a/arch/x86/include/asm/topology.h
> +++ b/arch/x86/include/asm/topology.h
> @@ -295,6 +295,8 @@ extern void arch_scale_freq_tick(void);
>  #ifdef CONFIG_ACPI_CPPC_LIB
>  void init_freq_invariance_cppc(void);
>  #define arch_init_invariance_cppc init_freq_invariance_cppc
> +#else
> +static inline void arch_init_invariance_cppc(void) { }
>  #endif
>
>  #endif /* _ASM_X86_TOPOLOGY_H */
> diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
> index ed91dfd4fdca..9d48cd706659 100644
> --- a/drivers/acpi/cppc_acpi.c
> +++ b/drivers/acpi/cppc_acpi.c
> @@ -671,10 +671,6 @@ static int pcc_data_alloc(int pcc_ss_id)
>   *  )
>   */
>
> -#ifndef arch_init_invariance_cppc
> -static inline void arch_init_invariance_cppc(void) { }
> -#endif
> -
>  /**
>   * acpi_cppc_processor_probe - Search for per CPU _CPC objects.
>   * @pr: Ptr to acpi_processor containing this CPU's logical ID.
> @@ -905,8 +901,6 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
>                 goto out_free;
>         }
>
> -       arch_init_invariance_cppc();
> -
>         kfree(output.pointer);
>         return 0;
>
> diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
> index cb52dd000b95..59620e7bc664 100644
> --- a/drivers/acpi/processor_driver.c
> +++ b/drivers/acpi/processor_driver.c
> @@ -270,6 +270,7 @@ static int __init acpi_processor_driver_init(void)
>                                   NULL, acpi_soft_cpu_dead);
>
>         acpi_processor_throttling_init();
> +       arch_init_invariance_cppc();
>         return 0;
>  err:
>         driver_unregister(&acpi_processor_driver);
> --

Applied as a fix for 6.12-rc7.

However, it would be good to add a comment explaining why
acpi_processor_driver_init() calls arch_init_invariance_cppc() at the
end.  The ACPI processor driver and CPPC are not otherwise related I
think?
Re: [PATCH v2] ACPI: processor: Move arch_init_invariance_cppc() call later
Posted by Mario Limonciello 2 weeks, 6 days ago 
On 11/4/2024 10:55, Rafael J. Wysocki wrote:
> On Sat, Nov 2, 2024 at 4:24 AM Mario Limonciello <superm1@kernel.org> wrote:
>>
>> From: Mario Limonciello <mario.limonciello@amd.com>
>>
>> arch_init_invariance_cppc() is called at the end of
>> acpi_cppc_processor_probe() in order to configure frequency invariance
>> based upon the values from _CPC.
>>
>> This however doesn't work on AMD CPPC shared memory designs that have
>> AMD preferred cores enabled because _CPC needs to be analyzed from all
>> cores to judge if preferred cores are enabled.
>>
>> This issue manifests to users as a warning since commit 21fb59ab4b97
>> ("ACPI: CPPC: Adjust debug messages in amd_set_max_freq_ratio() to warn"):
>> ```
>> Could not retrieve highest performance (-19)
>> ```
>>
>> However the warning isn't the cause of this, it was actually
>> commit 279f838a61f9 ("x86/amd: Detect preferred cores in
>> amd_get_boost_ratio_numerator()") which exposed the issue.
>>
>> To fix this problem, push the call to the arch_init_invariance_cppc()
>> macro to the end of acpi_processor_driver_init().
>>
>> Fixes: 279f838a61f9 ("x86/amd: Detect preferred cores in amd_get_boost_ratio_numerator()")
>> Reported-by: Ivan Shapovalov <intelfx@intelfx.name>
>> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219431
>> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
>> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
>> ---
>> v1->v2:
>>   * Fix LKP robot issue when CONFIG_ACPI_CPPC_LIB not defined
>> ---
>>   arch/x86/include/asm/topology.h | 2 ++
>>   drivers/acpi/cppc_acpi.c        | 6 ------
>>   drivers/acpi/processor_driver.c | 1 +
>>   3 files changed, 3 insertions(+), 6 deletions(-)
>>
>> diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
>> index abe3a8f22cbd..b04c5db7e945 100644
>> --- a/arch/x86/include/asm/topology.h
>> +++ b/arch/x86/include/asm/topology.h
>> @@ -295,6 +295,8 @@ extern void arch_scale_freq_tick(void);
>>   #ifdef CONFIG_ACPI_CPPC_LIB
>>   void init_freq_invariance_cppc(void);
>>   #define arch_init_invariance_cppc init_freq_invariance_cppc
>> +#else
>> +static inline void arch_init_invariance_cppc(void) { }
>>   #endif
>>
>>   #endif /* _ASM_X86_TOPOLOGY_H */
>> diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
>> index ed91dfd4fdca..9d48cd706659 100644
>> --- a/drivers/acpi/cppc_acpi.c
>> +++ b/drivers/acpi/cppc_acpi.c
>> @@ -671,10 +671,6 @@ static int pcc_data_alloc(int pcc_ss_id)
>>    *  )
>>    */
>>
>> -#ifndef arch_init_invariance_cppc
>> -static inline void arch_init_invariance_cppc(void) { }
>> -#endif
>> -
>>   /**
>>    * acpi_cppc_processor_probe - Search for per CPU _CPC objects.
>>    * @pr: Ptr to acpi_processor containing this CPU's logical ID.
>> @@ -905,8 +901,6 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
>>                  goto out_free;
>>          }
>>
>> -       arch_init_invariance_cppc();
>> -
>>          kfree(output.pointer);
>>          return 0;
>>
>> diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
>> index cb52dd000b95..59620e7bc664 100644
>> --- a/drivers/acpi/processor_driver.c
>> +++ b/drivers/acpi/processor_driver.c
>> @@ -270,6 +270,7 @@ static int __init acpi_processor_driver_init(void)
>>                                    NULL, acpi_soft_cpu_dead);
>>
>>          acpi_processor_throttling_init();
>> +       arch_init_invariance_cppc();
>>          return 0;
>>   err:
>>          driver_unregister(&acpi_processor_driver);
>> --
> 
> Applied as a fix for 6.12-rc7.
> 
> However, it would be good to add a comment explaining why
> acpi_processor_driver_init() calls arch_init_invariance_cppc() at the
> end.  The ACPI processor driver and CPPC are not otherwise related I
> think?

Sure, I'm thinking a comment like this.

/*
  * Frequency invariance calculations on AMD platforms can't be run until
  * _CPC has been evaluated on all processors which will only happen
  * after probing is complete.
  */

If that sounds good do you want to squash it in?  Or if you would prefer 
another commit tacked on that's no problem I'll do that.
Re: [PATCH v2] ACPI: processor: Move arch_init_invariance_cppc() call later
Posted by Rafael J. Wysocki 2 weeks, 5 days ago 
On Mon, Nov 4, 2024 at 6:17 PM Mario Limonciello <superm1@kernel.org> wrote:
>
> On 11/4/2024 10:55, Rafael J. Wysocki wrote:
> > On Sat, Nov 2, 2024 at 4:24 AM Mario Limonciello <superm1@kernel.org> wrote:
> >>
> >> From: Mario Limonciello <mario.limonciello@amd.com>
> >>
> >> arch_init_invariance_cppc() is called at the end of
> >> acpi_cppc_processor_probe() in order to configure frequency invariance
> >> based upon the values from _CPC.
> >>
> >> This however doesn't work on AMD CPPC shared memory designs that have
> >> AMD preferred cores enabled because _CPC needs to be analyzed from all
> >> cores to judge if preferred cores are enabled.
> >>
> >> This issue manifests to users as a warning since commit 21fb59ab4b97
> >> ("ACPI: CPPC: Adjust debug messages in amd_set_max_freq_ratio() to warn"):
> >> ```
> >> Could not retrieve highest performance (-19)
> >> ```
> >>
> >> However the warning isn't the cause of this, it was actually
> >> commit 279f838a61f9 ("x86/amd: Detect preferred cores in
> >> amd_get_boost_ratio_numerator()") which exposed the issue.
> >>
> >> To fix this problem, push the call to the arch_init_invariance_cppc()
> >> macro to the end of acpi_processor_driver_init().
> >>
> >> Fixes: 279f838a61f9 ("x86/amd: Detect preferred cores in amd_get_boost_ratio_numerator()")
> >> Reported-by: Ivan Shapovalov <intelfx@intelfx.name>
> >> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219431
> >> Tested-by: Oleksandr Natalenko <oleksandr@natalenko.name>
> >> Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
> >> ---
> >> v1->v2:
> >>   * Fix LKP robot issue when CONFIG_ACPI_CPPC_LIB not defined
> >> ---
> >>   arch/x86/include/asm/topology.h | 2 ++
> >>   drivers/acpi/cppc_acpi.c        | 6 ------
> >>   drivers/acpi/processor_driver.c | 1 +
> >>   3 files changed, 3 insertions(+), 6 deletions(-)
> >>
> >> diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
> >> index abe3a8f22cbd..b04c5db7e945 100644
> >> --- a/arch/x86/include/asm/topology.h
> >> +++ b/arch/x86/include/asm/topology.h
> >> @@ -295,6 +295,8 @@ extern void arch_scale_freq_tick(void);
> >>   #ifdef CONFIG_ACPI_CPPC_LIB
> >>   void init_freq_invariance_cppc(void);
> >>   #define arch_init_invariance_cppc init_freq_invariance_cppc
> >> +#else
> >> +static inline void arch_init_invariance_cppc(void) { }
> >>   #endif
> >>
> >>   #endif /* _ASM_X86_TOPOLOGY_H */
> >> diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
> >> index ed91dfd4fdca..9d48cd706659 100644
> >> --- a/drivers/acpi/cppc_acpi.c
> >> +++ b/drivers/acpi/cppc_acpi.c
> >> @@ -671,10 +671,6 @@ static int pcc_data_alloc(int pcc_ss_id)
> >>    *  )
> >>    */
> >>
> >> -#ifndef arch_init_invariance_cppc
> >> -static inline void arch_init_invariance_cppc(void) { }
> >> -#endif
> >> -
> >>   /**
> >>    * acpi_cppc_processor_probe - Search for per CPU _CPC objects.
> >>    * @pr: Ptr to acpi_processor containing this CPU's logical ID.
> >> @@ -905,8 +901,6 @@ int acpi_cppc_processor_probe(struct acpi_processor *pr)
> >>                  goto out_free;
> >>          }
> >>
> >> -       arch_init_invariance_cppc();
> >> -
> >>          kfree(output.pointer);
> >>          return 0;
> >>
> >> diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
> >> index cb52dd000b95..59620e7bc664 100644
> >> --- a/drivers/acpi/processor_driver.c
> >> +++ b/drivers/acpi/processor_driver.c
> >> @@ -270,6 +270,7 @@ static int __init acpi_processor_driver_init(void)
> >>                                    NULL, acpi_soft_cpu_dead);
> >>
> >>          acpi_processor_throttling_init();
> >> +       arch_init_invariance_cppc();
> >>          return 0;
> >>   err:
> >>          driver_unregister(&acpi_processor_driver);
> >> --
> >
> > Applied as a fix for 6.12-rc7.
> >
> > However, it would be good to add a comment explaining why
> > acpi_processor_driver_init() calls arch_init_invariance_cppc() at the
> > end.  The ACPI processor driver and CPPC are not otherwise related I
> > think?
>
> Sure, I'm thinking a comment like this.
>
> /*
>   * Frequency invariance calculations on AMD platforms can't be run until
>   * _CPC has been evaluated on all processors which will only happen
>   * after probing is complete.
>   */

It would be more precise to say "after acpi_cppc_processor_probe() has
been called for all online CPUs".

Which among other things means that the ordering of this call with
respect to acpi_processor_throttling_init() does not matter.

> If that sounds good do you want to squash it in?  Or if you would prefer
> another commit tacked on that's no problem I'll do that.

IMV a separate patch for 6.13 will be fine.

Patchew 2.1-devel-b67e4c2

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