[PATCH 1/2] powerpc/cpuidle: dynamically register/unregister cpuidle_device during hotplug

[Pingfan Liu]

cpuidle_device is touched during the cpu hotplug. At present, ppc64 just
online/offline cpu during hotplug/unplug. But if using the
register_cpu/unregister_cpu() API to implement the hotplug, the dir
/sys/../cpuX is created/destroyed during hotplug, hence we also need to
create the file cpuX/cpuidle dynamically.

Cc: Benjamin Herrenschmidt <benh at kernel.crashing.org>
Cc: Michael Ellerman <mpe at ellerman.id.au>
Cc: "Rafael J. Wysocki" <rjw at rjwysocki.net>
Cc: Tyrel Datwyler <tyreld at linux.vnet.ibm.com>
Cc: linux-pm at vger.kernel.org
Signed-off-by: Pingfan Liu <kernelfans at gmail.com>
---
 drivers/cpuidle/cpuidle-powernv.c | 2 ++
 drivers/cpuidle/cpuidle-pseries.c | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c
index d29e4f0..94d0def 100644
--- a/drivers/cpuidle/cpuidle-powernv.c
+++ b/drivers/cpuidle/cpuidle-powernv.c
@@ -166,6 +166,7 @@ static int powernv_cpuidle_cpu_online(unsigned int cpu)
 	struct cpuidle_device *dev = per_cpu(cpuidle_devices, cpu);
 
 	if (dev && cpuidle_get_driver()) {
+		cpuidle_register_device(dev);
 		cpuidle_pause_and_lock();
 		cpuidle_enable_device(dev);
 		cpuidle_resume_and_unlock();
@@ -181,6 +182,7 @@ static int powernv_cpuidle_cpu_dead(unsigned int cpu)
 		cpuidle_pause_and_lock();
 		cpuidle_disable_device(dev);
 		cpuidle_resume_and_unlock();
+		cpuidle_unregister_device(dev);
 	}
 	return 0;
 }
diff --git a/drivers/cpuidle/cpuidle-pseries.c b/drivers/cpuidle/cpuidle-pseries.c
index 9e56bc4..a53be8a 100644
--- a/drivers/cpuidle/cpuidle-pseries.c
+++ b/drivers/cpuidle/cpuidle-pseries.c
@@ -193,6 +193,7 @@ static int pseries_cpuidle_cpu_online(unsigned int cpu)
 	struct cpuidle_device *dev = per_cpu(cpuidle_devices, cpu);
 
 	if (dev && cpuidle_get_driver()) {
+		cpuidle_register_device(dev);
 		cpuidle_pause_and_lock();
 		cpuidle_enable_device(dev);
 		cpuidle_resume_and_unlock();
@@ -208,6 +209,7 @@ static int pseries_cpuidle_cpu_dead(unsigned int cpu)
 		cpuidle_pause_and_lock();
 		cpuidle_disable_device(dev);
 		cpuidle_resume_and_unlock();
+		cpuidle_unregister_device(dev);
 	}
 	return 0;
 }
-- 
2.7.4