On Wed, 3 Sep 2025 15:23:31 +0200
"Rafael J. Wysocki" [off-list ref] wrote:

On Wed, Sep 3, 2025 at 3:18 PM Zihuan Zhang [off-list ref] wrote:

quoted

Replace the manual cpufreq_cpu_put() with __free(put_cpufreq_policy)
annotation for policy references. This reduces the risk of reference
counting mistakes and aligns the code with the latest kernel style.

No functional change intended.

Signed-off-by: Zihuan Zhang <redacted>
---
 drivers/acpi/processor_thermal.c | 37 ++++++++++++++++++--------------
 1 file changed, 21 insertions(+), 16 deletions(-)

diff --git a/drivers/acpi/processor_thermal.c b/drivers/acpi/processor_thermal.c
index 1219adb11ab9..5043f17d27b7 100644
--- a/drivers/acpi/processor_thermal.c
+++ b/drivers/acpi/processor_thermal.c

@@ -62,19 +62,14 @@ static int phys_package_first_cpu(int cpu)
        return 0;
 }

-static int cpu_has_cpufreq(unsigned int cpu)
+static bool cpu_has_cpufreq(unsigned int cpu)
 {
-       struct cpufreq_policy *policy;
+       struct cpufreq_policy *policy __free(put_cpufreq_policy) = cpufreq_cpu_get(cpu);

I'd put the order back as it was.  See docs in cleanup.h, it is fine to
declare local variables inline if they are being use with __free()

That way if the simple check on acpi_process_cpu_freq_init fails no
get needs to occur.

So something like

static bool cpu_has_cpufreq(unsigned int cpu)
{
	if (!acpi_processor_cpufreq_init)
                 return 0;

	struct cpufreq_policy *policy __free(put_cpufreq_policy) = cpufreq_cpu_get(cpu);

	return policy != NULL; //Personally I find !! on a pointer a bit weird :)
}

quoted

        if (!acpi_processor_cpufreq_init)
                return 0;

-       policy = cpufreq_cpu_get(cpu);
-       if (policy) {
-               cpufreq_cpu_put(policy);
-               return 1;
-       }
-       return 0;
+       return !!policy;
 }

 static int cpufreq_get_max_state(unsigned int cpu)

@@ -93,9 +88,23 @@ static int cpufreq_get_cur_state(unsigned int cpu)
        return reduction_step(cpu);
 }

+static long long cpufreq_get_max_freq(unsigned int cpu)
+{
+       long long max_freq;
+       struct cpufreq_policy *policy __free(put_cpufreq_policy) =
+               cpufreq_cpu_get(cpu);

Format consistently.  If you are going to wrap to 80 chars here
then do it for the cpu_has_cpufreq() line that is identical to this.

quoted

+
+       if (!policy)
+               return -EINVAL;
+
+       max_freq = (policy->cpuinfo.max_freq *
+               (100 - reduction_step(cpu) * cpufreq_thermal_reduction_pctg)) / 100;
+
+       return max_freq;
+}
+
 static int cpufreq_set_cur_state(unsigned int cpu, int state)
 {
-       struct cpufreq_policy *policy;
        struct acpi_processor *pr;
        unsigned long max_freq;
        int i, ret;

@@ -120,14 +129,10 @@ static int cpufreq_set_cur_state(unsigned int cpu, int state)
                if (unlikely(!freq_qos_request_active(&pr->thermal_req)))
                        continue;

-               policy = cpufreq_cpu_get(i);
-               if (!policy)
-                       return -EINVAL;
-
-               max_freq = (policy->cpuinfo.max_freq *
-                           (100 - reduction_step(i) * cpufreq_thermal_reduction_pctg)) / 100;
+               max_freq = cpufreq_get_max_freq(cpu);

-               cpufreq_cpu_put(policy);
+               if (max_freq == -EINVAL)
+                       return -EINVAL;  

Please also move the code below to the new function so it does not
need to return a value.

quoted

                ret = freq_qos_update_request(&pr->thermal_req, max_freq);
                if (ret < 0) {
--