ACPI: processor: Do not expose global variable acpi_idle_driver

Move the cpuidle driver check from __acpi_processor_start() to
acpi_processor_power_init() which allows variable acpi_idle_driver to
become static.

No intentional functional impact.

Signed-off-by: Huisong Li <lihuisong@huawei.com>
Link: https://patch.msgid.link/20250923032428.2656329-2-lihuisong@huawei.com
[ rjw: Subject tweak, new changelog, adjustment of a new comment ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
index de17c14..5d82443 100644 (file)
--- a/drivers/acpi/processor_driver.c
+++ b/drivers/acpi/processor_driver.c
@@ -166,8 +166,7 @@ static int __acpi_processor_start(struct acpi_device *device)
        if (result && !IS_ENABLED(CONFIG_ACPI_CPU_FREQ_PSS))
                dev_dbg(&device->dev, "CPPC data invalid or not present\n");
 
-       if (cpuidle_get_driver() == &acpi_idle_driver)
-               acpi_processor_power_init(pr);
+       acpi_processor_power_init(pr);
 
        acpi_pss_perf_init(pr);
 

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 698d14c..22b051b 100644 (file)
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -51,7 +51,7 @@ module_param(latency_factor, uint, 0644);
 
 static DEFINE_PER_CPU(struct cpuidle_device *, acpi_cpuidle_device);
 
-struct cpuidle_driver acpi_idle_driver = {
+static struct cpuidle_driver acpi_idle_driver = {
        .name =         "acpi_idle",
        .owner =        THIS_MODULE,
 };
@@ -1404,6 +1404,13 @@ void acpi_processor_power_init(struct acpi_processor *pr)
 {
        struct cpuidle_device *dev;
 
+       /*
+        * The code below only works if the current cpuidle driver is the ACPI
+        * idle driver.
+        */
+       if (cpuidle_get_driver() != &acpi_idle_driver)
+               return;
+
        if (disabled_by_idle_boot_param())
                return;
 

diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index 24fdaa3..7146a8e 100644 (file)
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -417,7 +417,6 @@ static inline void acpi_processor_throttling_init(void) {}
 #endif /* CONFIG_ACPI_CPU_FREQ_PSS */
 
 /* in processor_idle.c */
-extern struct cpuidle_driver acpi_idle_driver;
 #ifdef CONFIG_ACPI_PROCESSOR_IDLE
 void acpi_processor_power_init(struct acpi_processor *pr);
 void acpi_processor_power_exit(struct acpi_processor *pr);