ACPI: processor: thermal: Update CPU cooling devices on cpufreq policy changes

BugLink: https://bugs.launchpad.net/bugs/2042697

When a cpufreq policy appears or goes away, the CPU cooling devices for
the CPUs covered by that policy need to be updated so that the new
processor_get_max_state() value is stored as max_state and the
statistics in sysfs are rearranged for each of them.

Do that accordingly in acpi_thermal_cpufreq_init() and
acpi_thermal_cpufreq_exit().

Fixes: a365105("thermal: sysfs: Reuse cdev->max_state")
Reported-by: Wang, Quanxian <[email protected]>
Link: https://lore.kernel.org/linux-pm/[email protected]
Signed-off-by: Rafael J. Wysocki <[email protected]>
Tested-by: Zhang Rui <[email protected]>
Reviewed-by: Zhang Rui <[email protected]>
(cherry picked from commit 22c52fa)
Acked-by: Nathan Hartman <[email protected]>
Acked-by: Jamie Nguyen <[email protected]>
Acked-by: Brad Figg <[email protected]>
Acked-by: Ian May <[email protected]>
Acked-by: Jacob Martin <[email protected]>

Author: rafaeljw

drivers/acpi/processor_thermal.c

@@ -140,9 +140,13 @@ void acpi_thermal_cpufreq_init(struct cpufreq_policy *policy)
 		ret = freq_qos_add_request(&policy->constraints,
 					   &pr->thermal_req,
 					   FREQ_QOS_MAX, INT_MAX);
-		if (ret < 0)
+		if (ret < 0) {
 			pr_err("Failed to add freq constraint for CPU%d (%d)\n",
 			       cpu, ret);
+			continue;
+		}
+
+		thermal_cooling_device_update(pr->cdev);
 	}
 }
 
@@ -153,8 +157,12 @@ void acpi_thermal_cpufreq_exit(struct cpufreq_policy *policy)
 	for_each_cpu(cpu, policy->related_cpus) {
 		struct acpi_processor *pr = per_cpu(processors, cpu);
 
-		if (pr)
-			freq_qos_remove_request(&pr->thermal_req);
+		if (!pr)
+			continue;
+
+		freq_qos_remove_request(&pr->thermal_req);
+
+		thermal_cooling_device_update(pr->cdev);
 	}
 }
 #else				/* ! CONFIG_CPU_FREQ */