ACPI: processor: idle: Remove useless codes about the verification of cstate count

[PATCH] ACPI: processor: idle: Remove useless codes about the verification of cstate count

Posted by Huisong Li 1 month, 2 weeks ago

The acpi_processor_setup_cstates and acpi_processor_setup_cpuidle_cx will
be called after successfully obtaining the power information. These setup
functions have their own main role, but also verify the validity of cstate
count.

Actually, the acpi_processor_get_power_info_cst will return failure if the
cstate count is zero and acpi_processor_get_power_info will return failure.

So the verification of cstate count in these functions are useless.

No intentional functional impact.

Signed-off-by: Huisong Li <lihuisong@huawei.com>
---
 drivers/acpi/processor_idle.c | 22 +++++++---------------
 1 file changed, 7 insertions(+), 15 deletions(-)

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 341825e8ac63..22909fccf0b1 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -732,8 +732,8 @@ static int __cpuidle acpi_idle_enter_s2idle(struct cpuidle_device *dev,
 	return 0;
 }
 
-static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
-					   struct cpuidle_device *dev)
+static void acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
+					    struct cpuidle_device *dev)
 {
 	int i, count = ACPI_IDLE_STATE_START;
 	struct acpi_processor_cx *cx;
@@ -753,14 +753,9 @@ static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
 		if (count == CPUIDLE_STATE_MAX)
 			break;
 	}
-
-	if (!count)
-		return -EINVAL;
-
-	return 0;
 }
 
-static int acpi_processor_setup_cstates(struct acpi_processor *pr)
+static void acpi_processor_setup_cstates(struct acpi_processor *pr)
 {
 	int i, count;
 	struct acpi_processor_cx *cx;
@@ -822,11 +817,6 @@ static int acpi_processor_setup_cstates(struct acpi_processor *pr)
 	}
 
 	drv->state_count = count;
-
-	if (!count)
-		return -EINVAL;
-
-	return 0;
 }
 
 static inline void acpi_processor_cstate_first_run_checks(void)
@@ -1241,7 +1231,8 @@ static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr)
 	if (pr->flags.has_lpi)
 		return acpi_processor_setup_lpi_states(pr);
 
-	return acpi_processor_setup_cstates(pr);
+	acpi_processor_setup_cstates(pr);
+	return 0;
 }
 
 /**
@@ -1261,7 +1252,8 @@ static int acpi_processor_setup_cpuidle_dev(struct acpi_processor *pr,
 	if (pr->flags.has_lpi)
 		return acpi_processor_ffh_lpi_probe(pr->id);
 
-	return acpi_processor_setup_cpuidle_cx(pr, dev);
+	acpi_processor_setup_cpuidle_cx(pr, dev);
+	return 0;
 }
 
 static int acpi_processor_get_power_info(struct acpi_processor *pr)
-- 
2.33.0

Re: [PATCH] ACPI: processor: idle: Remove useless codes about the verification of cstate count

Posted by Rafael J. Wysocki 1 month, 1 week ago

On Wed, Nov 5, 2025 at 10:36 AM Huisong Li <lihuisong@huawei.com> wrote:
>
> The acpi_processor_setup_cstates and acpi_processor_setup_cpuidle_cx will
> be called after successfully obtaining the power information. These setup
> functions have their own main role, but also verify the validity of cstate
> count.
>
> Actually, the acpi_processor_get_power_info_cst will return failure if the
> cstate count is zero and acpi_processor_get_power_info will return failure.
>
> So the verification of cstate count in these functions are useless.
>
> No intentional functional impact.
>
> Signed-off-by: Huisong Li <lihuisong@huawei.com>
> ---
>  drivers/acpi/processor_idle.c | 22 +++++++---------------
>  1 file changed, 7 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
> index 341825e8ac63..22909fccf0b1 100644
> --- a/drivers/acpi/processor_idle.c
> +++ b/drivers/acpi/processor_idle.c
> @@ -732,8 +732,8 @@ static int __cpuidle acpi_idle_enter_s2idle(struct cpuidle_device *dev,
>         return 0;
>  }
>
> -static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
> -                                          struct cpuidle_device *dev)
> +static void acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
> +                                           struct cpuidle_device *dev)
>  {
>         int i, count = ACPI_IDLE_STATE_START;
>         struct acpi_processor_cx *cx;
> @@ -753,14 +753,9 @@ static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
>                 if (count == CPUIDLE_STATE_MAX)
>                         break;
>         }
> -
> -       if (!count)
> -               return -EINVAL;
> -
> -       return 0;
>  }
>
> -static int acpi_processor_setup_cstates(struct acpi_processor *pr)
> +static void acpi_processor_setup_cstates(struct acpi_processor *pr)
>  {
>         int i, count;
>         struct acpi_processor_cx *cx;
> @@ -822,11 +817,6 @@ static int acpi_processor_setup_cstates(struct acpi_processor *pr)
>         }
>
>         drv->state_count = count;
> -
> -       if (!count)
> -               return -EINVAL;
> -
> -       return 0;
>  }
>
>  static inline void acpi_processor_cstate_first_run_checks(void)
> @@ -1241,7 +1231,8 @@ static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr)
>         if (pr->flags.has_lpi)
>                 return acpi_processor_setup_lpi_states(pr);
>
> -       return acpi_processor_setup_cstates(pr);
> +       acpi_processor_setup_cstates(pr);
> +       return 0;
>  }
>
>  /**
> @@ -1261,7 +1252,8 @@ static int acpi_processor_setup_cpuidle_dev(struct acpi_processor *pr,
>         if (pr->flags.has_lpi)
>                 return acpi_processor_ffh_lpi_probe(pr->id);
>
> -       return acpi_processor_setup_cpuidle_cx(pr, dev);
> +       acpi_processor_setup_cpuidle_cx(pr, dev);
> +       return 0;
>  }
>
>  static int acpi_processor_get_power_info(struct acpi_processor *pr)
> --

Applied as 6.19 material with rewritten subject and changelog, thanks!