From 46bcfad7a819bd17ac4e831b04405152d59784ab Mon Sep 17 00:00:00 2001 From: Deepthi Dharwar Date: Fri, 28 Oct 2011 16:20:42 +0530 Subject: cpuidle: Single/Global registration of idle states This patch makes the cpuidle_states structure global (single copy) instead of per-cpu. The statistics needed on per-cpu basis by the governor are kept per-cpu. This simplifies the cpuidle subsystem as state registration is done by single cpu only. Having single copy of cpuidle_states saves memory. Rare case of asymmetric C-states can be handled within the cpuidle driver and architectures such as POWER do not have asymmetric C-states. Having single/global registration of all the idle states, dynamic C-state transitions on x86 are handled by the boot cpu. Here, the boot cpu would disable all the devices, re-populate the states and later enable all the devices, irrespective of the cpu that would receive the notification first. Reference: https://lkml.org/lkml/2011/4/25/83 Signed-off-by: Deepthi Dharwar Signed-off-by: Trinabh Gupta Tested-by: Jean Pihet Reviewed-by: Kevin Hilman Acked-by: Arjan van de Ven Acked-by: Kevin Hilman Signed-off-by: Len Brown --- drivers/cpuidle/sysfs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/cpuidle/sysfs.c') diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c index 8a1ace104476..1e756e160dca 100644 --- a/drivers/cpuidle/sysfs.c +++ b/drivers/cpuidle/sysfs.c @@ -322,13 +322,14 @@ int cpuidle_add_state_sysfs(struct cpuidle_device *device) { int i, ret = -ENOMEM; struct cpuidle_state_kobj *kobj; + struct cpuidle_driver *drv = cpuidle_get_driver(); /* state statistics */ for (i = 0; i < device->state_count; i++) { kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL); if (!kobj) goto error_state; - kobj->state = &device->states[i]; + kobj->state = &drv->states[i]; kobj->state_usage = &device->states_usage[i]; init_completion(&kobj->kobj_unregister); -- cgit v1.2.3