[v4] ACPI: processor: Move arch_init_invariance_cppc() call later

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, change arch_init_invariance_cppc() into a new weak
symbol that is called at the end of acpi_processor_driver_init().
Each architecture that supports it can declare the symbol to override
the weak one.

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>
---
v4:
 * Drop macros and only use symbols
v3:
 * Weak symbol instead of macro to help riscv build failure
 * Update commit message
 * Add comment
---
 arch/arm64/include/asm/topology.h | 4 ----
 arch/x86/include/asm/topology.h   | 5 -----
 arch/x86/kernel/acpi/cppc.c       | 7 ++++++-
 drivers/acpi/cppc_acpi.c          | 6 ------
 drivers/acpi/processor_driver.c   | 9 +++++++++
 drivers/base/arch_topology.c      | 6 +++++-
 include/acpi/processor.h          | 2 ++
 include/linux/arch_topology.h     | 4 ----
 8 files changed, 22 insertions(+), 21 deletions(-)


base-commit: 6db936d4ac0fe281af48b4d1ebf69b1523bbac31

On Mon, Nov 4, 2024 at 11:29 PM 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, change arch_init_invariance_cppc() into a new weak
> symbol that is called at the end of acpi_processor_driver_init().
> Each architecture that supports it can declare the symbol to override
> the weak one.

"Define it for x86, in arch/x86/kernel/acpi/cppc.c, and for all of the
architectures using the generic arch_topology.c code."

> 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>
> ---
> v4:
>  * Drop macros and only use symbols
> v3:
>  * Weak symbol instead of macro to help riscv build failure
>  * Update commit message
>  * Add comment
> ---
>  arch/arm64/include/asm/topology.h | 4 ----
>  arch/x86/include/asm/topology.h   | 5 -----
>  arch/x86/kernel/acpi/cppc.c       | 7 ++++++-
>  drivers/acpi/cppc_acpi.c          | 6 ------
>  drivers/acpi/processor_driver.c   | 9 +++++++++
>  drivers/base/arch_topology.c      | 6 +++++-
>  include/acpi/processor.h          | 2 ++
>  include/linux/arch_topology.h     | 4 ----
>  8 files changed, 22 insertions(+), 21 deletions(-)
>
> diff --git a/arch/arm64/include/asm/topology.h b/arch/arm64/include/asm/topology.h
> index 5fc3af9f8f29b..341174bf91063 100644
> --- a/arch/arm64/include/asm/topology.h
> +++ b/arch/arm64/include/asm/topology.h
> @@ -26,10 +26,6 @@ void update_freq_counters_refs(void);
>  #define arch_scale_freq_invariant topology_scale_freq_invariant
>  #define arch_scale_freq_ref topology_get_freq_ref
>
> -#ifdef CONFIG_ACPI_CPPC_LIB
> -#define arch_init_invariance_cppc topology_init_cpu_capacity_cppc
> -#endif
> -
>  /* Replace task scheduler's default cpu-invariant accounting */
>  #define arch_scale_cpu_capacity topology_get_cpu_scale
>
> diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
> index aef70336d6247..92f3664dd933b 100644
> --- a/arch/x86/include/asm/topology.h
> +++ b/arch/x86/include/asm/topology.h
> @@ -305,9 +305,4 @@ static inline void freq_invariance_set_perf_ratio(u64 ratio, bool turbo_disabled
>  extern void arch_scale_freq_tick(void);
>  #define arch_scale_freq_tick arch_scale_freq_tick
>
> -#ifdef CONFIG_ACPI_CPPC_LIB
> -void init_freq_invariance_cppc(void);
> -#define arch_init_invariance_cppc init_freq_invariance_cppc
> -#endif
> -
>  #endif /* _ASM_X86_TOPOLOGY_H */
> diff --git a/arch/x86/kernel/acpi/cppc.c b/arch/x86/kernel/acpi/cppc.c
> index 956984054bf30..aab9d0570841a 100644
> --- a/arch/x86/kernel/acpi/cppc.c
> +++ b/arch/x86/kernel/acpi/cppc.c
> @@ -110,7 +110,7 @@ static void amd_set_max_freq_ratio(void)
>
>  static DEFINE_MUTEX(freq_invariance_lock);
>
> -void init_freq_invariance_cppc(void)
> +static inline void init_freq_invariance_cppc(void)
>  {
>         static bool init_done;
>
> @@ -127,6 +127,11 @@ void init_freq_invariance_cppc(void)
>         mutex_unlock(&freq_invariance_lock);
>  }
>
> +void acpi_processor_init_invariance_cppc(void)
> +{
> +       init_freq_invariance_cppc();
> +}
> +
>  /*
>   * Get the highest performance register value.
>   * @cpu: CPU from which to get highest performance.
> diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c
> index 1a40f0514eaa3..5c0cc7aae8726 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 cb52dd000b958..3b281bc1e73c3 100644
> --- a/drivers/acpi/processor_driver.c
> +++ b/drivers/acpi/processor_driver.c
> @@ -237,6 +237,9 @@ static struct notifier_block acpi_processor_notifier_block = {
>         .notifier_call = acpi_processor_notifier,
>  };
>
> +void __weak acpi_processor_init_invariance_cppc(void)
> +{ }
> +
>  /*
>   * We keep the driver loaded even when ACPI is not running.
>   * This is needed for the powernow-k8 driver, that works even without
> @@ -270,6 +273,12 @@ static int __init acpi_processor_driver_init(void)
>                                   NULL, acpi_soft_cpu_dead);
>
>         acpi_processor_throttling_init();
> +
> +       /*
> +        * Frequency invariance calculations on AMD platforms can't be run until
> +        * after acpi_cppc_processor_probe() has been called for all online CPUs
> +        */
> +       acpi_processor_init_invariance_cppc();
>         return 0;
>  err:
>         driver_unregister(&acpi_processor_driver);
> diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c
> index 75fcb75d55155..3ebe77566788b 100644
> --- a/drivers/base/arch_topology.c
> +++ b/drivers/base/arch_topology.c
> @@ -366,7 +366,7 @@ void __weak freq_inv_set_max_ratio(int cpu, u64 max_rate)
>  #ifdef CONFIG_ACPI_CPPC_LIB
>  #include <acpi/cppc_acpi.h>
>
> -void topology_init_cpu_capacity_cppc(void)
> +static inline void topology_init_cpu_capacity_cppc(void)
>  {
>         u64 capacity, capacity_scale = 0;
>         struct cppc_perf_caps perf_caps;
> @@ -417,6 +417,10 @@ void topology_init_cpu_capacity_cppc(void)
>  exit:
>         free_raw_capacity();
>  }
> +void acpi_processor_init_invariance_cppc(void)
> +{
> +       topology_init_cpu_capacity_cppc();
> +}
>  #endif
>
>  #ifdef CONFIG_CPU_FREQ
> diff --git a/include/acpi/processor.h b/include/acpi/processor.h
> index e6f6074eadbf3..a17e97e634a68 100644
> --- a/include/acpi/processor.h
> +++ b/include/acpi/processor.h
> @@ -465,4 +465,6 @@ extern int acpi_processor_ffh_lpi_probe(unsigned int cpu);
>  extern int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi);
>  #endif
>
> +void acpi_processor_init_invariance_cppc(void);
> +
>  #endif
> diff --git a/include/linux/arch_topology.h b/include/linux/arch_topology.h
> index b721f360d7592..4a952c4885edc 100644
> --- a/include/linux/arch_topology.h
> +++ b/include/linux/arch_topology.h
> @@ -11,10 +11,6 @@
>  void topology_normalize_cpu_scale(void);
>  int topology_update_cpu_topology(void);
>
> -#ifdef CONFIG_ACPI_CPPC_LIB
> -void topology_init_cpu_capacity_cppc(void);
> -#endif
> -
>  struct device_node;
>  bool topology_parse_cpu_capacity(struct device_node *cpu_node, int cpu);
>
>
> base-commit: 6db936d4ac0fe281af48b4d1ebf69b1523bbac31
> --
> 2.43.0
>

On Tue, Nov 5, 2024 at 9:17 PM Rafael J. Wysocki <rafael@kernel.org> wrote:
>
> On Mon, Nov 4, 2024 at 11:29 PM 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, change arch_init_invariance_cppc() into a new weak
> > symbol that is called at the end of acpi_processor_driver_init().
> > Each architecture that supports it can declare the symbol to override
> > the weak one.
>
> "Define it for x86, in arch/x86/kernel/acpi/cppc.c, and for all of the
> architectures using the generic arch_topology.c code."

I've added this to the patch changelog and queued it up as a 6.12 fix.

Thanks!

On 11/6/2024 14:33, Rafael J. Wysocki wrote:
> On Tue, Nov 5, 2024 at 9:17 PM Rafael J. Wysocki <rafael@kernel.org> wrote:
>>
>> On Mon, Nov 4, 2024 at 11:29 PM 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, change arch_init_invariance_cppc() into a new weak
>>> symbol that is called at the end of acpi_processor_driver_init().
>>> Each architecture that supports it can declare the symbol to override
>>> the weak one.
>>
>> "Define it for x86, in arch/x86/kernel/acpi/cppc.c, and for all of the
>> architectures using the generic arch_topology.c code."
> 
> I've added this to the patch changelog and queued it up as a 6.12 fix.
> 
> Thanks!

Thanks!