diff options
| author | Deepthi Dharwar <deepthi@linux.vnet.ibm.com> | 2011-10-28 16:20:42 +0530 |
|---|---|---|
| committer | Len Brown <len.brown@intel.com> | 2011-11-06 21:13:58 -0500 |
| commit | 46bcfad7a819bd17ac4e831b04405152d59784ab (patch) | |
| tree | 20041e788154d103edff2699f88d4a30320e3ee2 /include/linux | |
| parent | 4202735e8ab6ecfb0381631a0d0b58fefe0bd4e2 (diff) | |
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 <deepthi@linux.vnet.ibm.com>
Signed-off-by: Trinabh Gupta <g.trinabh@gmail.com>
Tested-by: Jean Pihet <j-pihet@ti.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/cpuidle.h | 19 |
1 files changed, 13 insertions, 6 deletions
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index 0156540b3f7..c90418822f4 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -22,6 +22,7 @@ #define CPUIDLE_DESC_LEN 32 struct cpuidle_device; +struct cpuidle_driver; /**************************** @@ -45,6 +46,7 @@ struct cpuidle_state { unsigned int target_residency; /* in US */ int (*enter) (struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index); }; @@ -83,12 +85,10 @@ struct cpuidle_state_kobj { struct cpuidle_device { unsigned int registered:1; unsigned int enabled:1; - unsigned int power_specified:1; unsigned int cpu; int last_residency; int state_count; - struct cpuidle_state states[CPUIDLE_STATE_MAX]; struct cpuidle_state_usage states_usage[CPUIDLE_STATE_MAX]; struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX]; @@ -96,7 +96,6 @@ struct cpuidle_device { struct kobject kobj; struct completion kobj_unregister; void *governor_data; - int safe_state_index; }; DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices); @@ -120,6 +119,11 @@ static inline int cpuidle_get_last_residency(struct cpuidle_device *dev) struct cpuidle_driver { char name[CPUIDLE_NAME_LEN]; struct module *owner; + + unsigned int power_specified:1; + struct cpuidle_state states[CPUIDLE_STATE_MAX]; + int state_count; + int safe_state_index; }; #ifdef CONFIG_CPU_IDLE @@ -166,10 +170,13 @@ struct cpuidle_governor { struct list_head governor_list; unsigned int rating; - int (*enable) (struct cpuidle_device *dev); - void (*disable) (struct cpuidle_device *dev); + int (*enable) (struct cpuidle_driver *drv, + struct cpuidle_device *dev); + void (*disable) (struct cpuidle_driver *drv, + struct cpuidle_device *dev); - int (*select) (struct cpuidle_device *dev); + int (*select) (struct cpuidle_driver *drv, + struct cpuidle_device *dev); void (*reflect) (struct cpuidle_device *dev, int index); struct module *owner; |