cpuidle/pseries: Convert to hotplug state machine

Install the callbacks via the state machine.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-pm@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160818125731.27256-11-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

2 files changed, 25 insertions, 27 deletions

diff --git a/drivers/cpuidle/cpuidle-pseries.c b/drivers/cpuidle/cpuidle-pseries.c
index 07135e009d8b..166ccd711ec9 100644
--- a/drivers/cpuidle/cpuidle-pseries.c
+++ b/drivers/cpuidle/cpuidle-pseries.c
@@ -171,40 +171,30 @@ static struct cpuidle_state shared_states[] = {
                 .enter = &shared_cede_loop },
 };
 
-static int pseries_cpuidle_add_cpu_notifier(struct notifier_block *n,
-                        unsigned long action, void *hcpu)
+static int pseries_cpuidle_cpu_online(unsigned int cpu)
 {
-        int hotcpu = (unsigned long)hcpu;
-        struct cpuidle_device *dev =
-                                per_cpu(cpuidle_devices, hotcpu);
+        struct cpuidle_device *dev = per_cpu(cpuidle_devices, cpu);
 
         if (dev && cpuidle_get_driver()) {
-                switch (action) {
-                case CPU_ONLINE:
-                case CPU_ONLINE_FROZEN:
-                        cpuidle_pause_and_lock();
-                        cpuidle_enable_device(dev);
-                        cpuidle_resume_and_unlock();
-                        break;
+                cpuidle_pause_and_lock();
+                cpuidle_enable_device(dev);
+                cpuidle_resume_and_unlock();
+        }
+        return 0;
+}
 
-                case CPU_DEAD:
-                case CPU_DEAD_FROZEN:
-                        cpuidle_pause_and_lock();
-                        cpuidle_disable_device(dev);
-                        cpuidle_resume_and_unlock();
-                        break;
+static int pseries_cpuidle_cpu_dead(unsigned int cpu)
+{
+        struct cpuidle_device *dev = per_cpu(cpuidle_devices, cpu);
 
-                default:
-                        return NOTIFY_DONE;
-                }
+        if (dev && cpuidle_get_driver()) {
+                cpuidle_pause_and_lock();
+                cpuidle_disable_device(dev);
+                cpuidle_resume_and_unlock();
         }
-        return NOTIFY_OK;
+        return 0;
 }
 
-static struct notifier_block setup_hotplug_notifier = {
-        .notifier_call = pseries_cpuidle_add_cpu_notifier,
-};
-
 /*
  * pseries_cpuidle_driver_init()
  */
@@ -273,7 +263,14 @@ static int __init pseries_processor_idle_init(void)
                 return retval;
         }
 
-        register_cpu_notifier(&setup_hotplug_notifier);
+        retval = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
+                                           "cpuidle/pseries:online",
+                                           pseries_cpuidle_cpu_online, NULL);
+        WARN_ON(retval < 0);
+        retval = cpuhp_setup_state_nocalls(CPUHP_CPUIDLE_DEAD,
+                                           "cpuidle/pseries:DEAD", NULL,
+                                           pseries_cpuidle_cpu_dead);
+        WARN_ON(retval < 0);
         printk(KERN_DEBUG "pseries_idle_driver registered\n");
         return 0;
 }
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 4066c74bb73c..0fb22b95649f 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -19,6 +19,7 @@ enum cpuhp_state {
         CPUHP_MM_WRITEBACK_DEAD,
         CPUHP_SOFTIRQ_DEAD,
         CPUHP_NET_MVNETA_DEAD,
+        CPUHP_CPUIDLE_DEAD,
         CPUHP_WORKQUEUE_PREP,
         CPUHP_POWER_NUMA_PREPARE,
         CPUHP_HRTIMERS_PREPARE,