ACPI: processor: thermal: Release policy references using __free()

Replace the manual cpufreq_cpu_put() with __free(put_cpufreq_policy)
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 <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
[ rjw: Subject and changelog edits, whitespace fixups ]
Signed-off-by: Rafael J. Wysocki <[e-mail]>

drivers/acpi/processor_thermal.c

···
 	return 0;
 }
 
-static int cpu_has_cpufreq(unsigned int cpu)
+static bool cpu_has_cpufreq(unsigned int cpu)
 {
-	struct cpufreq_policy *policy;
-
 	if (!acpi_processor_cpufreq_init)
 		return 0;
 
-	policy = cpufreq_cpu_get(cpu);
-	if (policy) {
-		cpufreq_cpu_put(policy);
-		return 1;
-	}
-	return 0;
+	struct cpufreq_policy *policy __free(put_cpufreq_policy) = cpufreq_cpu_get(cpu);
+
+	return policy != NULL;
 }
 
 static int cpufreq_get_max_state(unsigned int cpu)
···
 	return reduction_step(cpu);
 }
 
+static bool cpufreq_update_thermal_limit(unsigned int cpu, struct acpi_processor *pr)
+{
+	unsigned long max_freq;
+	int ret;
+
+	struct cpufreq_policy *policy __free(put_cpufreq_policy) = cpufreq_cpu_get(cpu);
+	if (!policy)
+		return false;
+
+	max_freq = (policy->cpuinfo.max_freq *
+		(100 - reduction_step(cpu) * cpufreq_thermal_reduction_pctg)) / 100;
+
+	ret = freq_qos_update_request(&pr->thermal_req, max_freq);
+	if (ret < 0) {
+		pr_warn("Failed to update thermal freq constraint: CPU%d (%d)\n",
+			pr->id, ret);
+	}
+
+	return true;
+}
+
 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;
+	int i;
 
 	if (!cpu_has_cpufreq(cpu))
 		return 0;
···
 		if (unlikely(!freq_qos_request_active(&pr->thermal_req)))
 			continue;
 
-		policy = cpufreq_cpu_get(i);
-		if (!policy)
+		if (!cpufreq_update_thermal_limit(i, pr))
 			return -EINVAL;
-
-		max_freq = (policy->cpuinfo.max_freq *
-			    (100 - reduction_step(i) * cpufreq_thermal_reduction_pctg)) / 100;
-
-		cpufreq_cpu_put(policy);
-
-		ret = freq_qos_update_request(&pr->thermal_req, max_freq);
-		if (ret < 0) {
-			pr_warn("Failed to update thermal freq constraint: CPU%d (%d)\n",
-				pr->id, ret);
-		}
 	}
 	return 0;
 }