[v12 PATCH 1/8]: cpuidle: cleanup cpuidle.h header file.

Arun R Bharadwaj
2010-04-15T11:05:38Z

This patch re-designs the data structures used in cpuidle infrastructure.
Currently, we have a per-cpu device structure. Each cpu needs to register
under cpuidle as a cpuidle_device. This is not desirable and hence the
per-cpu registration is removed by this patch.

This patch introduces a cpuidle_subsystem structure. This needs a one-time
registration to cpuidle. Also the current design has an array of the idle states
for each of the CPUs. This is changed to have a global array of idle states.
The statistics data like 'usage' and 'time' which were earlier part of the
cpuidle_states structure is biforcated to form a new structure cpuidle_stats,
which is per-cpu.

Signed-off-by: Arun R Bharadwaj <arun@linux.vnet.ibm.com>
---
drivers/cpuidle/cpuidle.h | 6 +--
include/linux/cpuidle.h | 70 ++++++++++++++++++++--------------------------
2 files changed, 33 insertions(+), 43 deletions(-)

Index: linux.trees.git/include/linux/cpuidle.h
===================================================================
--- linux.trees.git.orig/include/linux/cpuidle.h
+++ linux.trees.git/include/linux/cpuidle.h
@@ -20,8 +20,7 @@
#define CPUIDLE_STATE_MAX 8
#define CPUIDLE_NAME_LEN 16
#define CPUIDLE_DESC_LEN 32
-
-struct cpuidle_device;
+#define CPUIDLE_MAX_CPUS 128

/****************************
@@ -38,11 +37,11 @@ struct cpuidle_state {
unsigned int power_usage; /* in mW */
unsigned int target_residency; /* in US */

- unsigned long long usage;
- unsigned long long time; /* in US */
+ int state_index;
+ unsigned long long *usage;
+ unsigned long long *time;

- int (*enter) (struct cpuidle_device *dev,
- struct cpuidle_state *state);
+ int (*enter) (struct cpuidle_state *state);
};

/* Idle State Flags */
@@ -76,30 +75,31 @@ cpuidle_set_statedata(struct cpuidle_sta
}

struct cpuidle_state_kobj {
+ int cpuid;
struct cpuidle_state *state;
struct completion kobj_unregister;
struct kobject kobj;
};

-struct cpuidle_device {
- unsigned int registered:1;
- unsigned int enabled:1;
- unsigned int cpu;
-
- int last_residency;
- int state_count;
- struct cpuidle_state states[CPUIDLE_STATE_MAX];
+struct cpuidle_stats {
+ unsigned long long usage[CPUIDLE_STATE_MAX];
+ unsigned long long time[CPUIDLE_STATE_MAX]; /* in US */
struct cpuidle_state_kobj *kobjs[CPUIDLE_STATE_MAX];
- struct cpuidle_state *last_state;
-
- struct list_head device_list;
struct kobject kobj;
struct completion kobj_unregister;
- void *governor_data;
+};
+
+struct cpuidle_subsystem {
+ unsigned int registered:1;
+ int state_count;
+ int last_residency[CPUIDLE_MAX_CPUS];
+ struct cpuidle_state *last_state[CPUIDLE_MAX_CPUS];
+ struct cpuidle_state states[CPUIDLE_STATE_MAX];
struct cpuidle_state *safe_state;
};

-DECLARE_PER_CPU(struct cpuidle_device *, cpuidle_devices);
+extern struct cpuidle_subsystem cpuidle_subsys;
+DECLARE_PER_CPU(struct cpuidle_stats, stats);

/**
* cpuidle_get_last_residency - retrieves the last state's residency time
@@ -107,9 +107,9 @@ DECLARE_PER_CPU(struct cpuidle_device *,
*
* NOTE: this value is invalid if CPUIDLE_FLAG_TIME_VALID isn't set
*/
-static inline int cpuidle_get_last_residency(struct cpuidle_device *dev)
+static inline int cpuidle_get_last_residency(int cpu)
{
- return dev->last_residency;
+ return cpuidle_subsys.last_residency[cpu];
}

@@ -123,32 +123,23 @@ struct cpuidle_driver {
};

#ifdef CONFIG_CPU_IDLE
-
extern int cpuidle_register_driver(struct cpuidle_driver *drv);
extern void cpuidle_unregister_driver(struct cpuidle_driver *drv);
-extern int cpuidle_register_device(struct cpuidle_device *dev);
-extern void cpuidle_unregister_device(struct cpuidle_device *dev);
+extern int cpuidle_register_subsystem(int state_count);
+extern void cpuidle_unregister_subsystem(void);

extern void cpuidle_pause_and_lock(void);
extern void cpuidle_resume_and_unlock(void);
-extern int cpuidle_enable_device(struct cpuidle_device *dev);
-extern void cpuidle_disable_device(struct cpuidle_device *dev);
-
#else
-
static inline int cpuidle_register_driver(struct cpuidle_driver *drv)
{return 0;}
static inline void cpuidle_unregister_driver(struct cpuidle_driver *drv) { }
-static inline int cpuidle_register_device(struct cpuidle_device *dev)
+static inline int cpuidle_register_subsystem(int state_count)
{return 0;}
-static inline void cpuidle_unregister_device(struct cpuidle_device *dev) { }
-
+static inline void cpuidle_unregister_subsystem(void)
+{ }
static inline void cpuidle_pause_and_lock(void) { }
static inline void cpuidle_resume_and_unlock(void) { }
-static inline int cpuidle_enable_device(struct cpuidle_device *dev)
-{return 0;}
-static inline void cpuidle_disable_device(struct cpuidle_device *dev) { }
-
#endif

/******************************
@@ -160,11 +151,11 @@ 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) (int cpu);
+ void (*disable) (int cpu);

- int (*select) (struct cpuidle_device *dev);
- void (*reflect) (struct cpuidle_device *dev);
+ int (*select) (int cpu);
+ void (*reflect) (int cpu);

struct module *owner;
};
@@ -187,5 +178,6 @@ static inline void cpuidle_unregister_go
#else
#define CPUIDLE_DRIVER_STATE_START 0
#endif
+extern void cpuidle_idle_call(void);

#endif /* _LINUX_CPUIDLE_H */
Index: linux.trees.git/drivers/cpuidle/cpuidle.h
===================================================================
--- linux.trees.git.orig/drivers/cpuidle/cpuidle.h
+++ linux.trees.git/drivers/cpuidle/cpuidle.h
@@ -11,12 +11,10 @@
extern struct cpuidle_governor *cpuidle_curr_governor;
extern struct cpuidle_driver *cpuidle_curr_driver;
extern struct list_head cpuidle_governors;
-extern struct list_head cpuidle_detected_devices;
extern struct mutex cpuidle_lock;
extern spinlock_t cpuidle_driver_lock;

/* idle loop */
-extern void cpuidle_install_idle_handler(void);
extern void cpuidle_uninstall_idle_handler(void);

/* governors */
@@ -25,8 +23,8 @@ extern int cpuidle_switch_governor(struc
/* sysfs */
extern int cpuidle_add_class_sysfs(struct sysdev_class *cls);
extern void cpuidle_remove_class_sysfs(struct sysdev_class *cls);
-extern int cpuidle_add_state_sysfs(struct cpuidle_device *device);
-extern void cpuidle_remove_state_sysfs(struct cpuidle_device *device);
+extern int cpuidle_add_state_sysfs(int cpu);
+extern void cpuidle_remove_state_sysfs(int cpu);
extern int cpuidle_add_sysfs(struct sys_device *sysdev);
extern void cpuidle_remove_sysfs(struct sys_device *sysdev);