diff options
-rw-r--r-- | drivers/cpuidle/cpuidle.c | 96 | ||||
-rw-r--r-- | include/linux/cpuidle.h | 19 |
2 files changed, 94 insertions, 21 deletions
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 09d05ab..1506d69 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -65,6 +65,26 @@ int cpuidle_play_dead(void) } /** + * cpuidle_enabled - check if the cpuidle framework is ready + * @dev: cpuidle device for this cpu + * @drv: cpuidle driver for this cpu + * + * Return 0 on success, otherwise: + * -NODEV : the cpuidle framework is not available + * -EBUSY : the cpuidle framework is not initialized + */ +int cpuidle_enabled(struct cpuidle_driver *drv, struct cpuidle_device *dev) +{ + if (off || !initialized) + return -ENODEV; + + if (!drv || !dev || !dev->enabled) + return -EBUSY; + + return 0; +} + +/** * cpuidle_enter_state - enter the state and update stats * @dev: cpuidle device for this cpu * @drv: cpuidle driver for this cpu @@ -108,6 +128,51 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv, } /** + * cpuidle_select - ask the cpuidle framework to choose an idle state + * + * @drv: the cpuidle driver + * @dev: the cpuidle device + * + * Returns the index of the idle state. + */ +int cpuidle_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) +{ + return cpuidle_curr_governor->select(drv, dev); +} + +/** + * cpuidle_enter - enter into the specified idle state + * + * @drv: the cpuidle driver tied with the cpu + * @dev: the cpuidle device + * @index: the index in the idle state table + * + * Returns the index in the idle state, < 0 in case of error. + * The error code depends on the backend driver + */ +int cpuidle_enter(struct cpuidle_driver *drv, struct cpuidle_device *dev, + int index) +{ + if (cpuidle_state_is_coupled(dev, drv, index)) + return cpuidle_enter_state_coupled(dev, drv, index); + return cpuidle_enter_state(dev, drv, index); +} + +/** + * cpuidle_reflect - tell the underlying governor what was the state + * we were in + * + * @dev : the cpuidle device + * @index: the index in the idle state table + * + */ +void cpuidle_reflect(struct cpuidle_device *dev, int index) +{ + if (cpuidle_curr_governor->reflect) + cpuidle_curr_governor->reflect(dev, index); +} + +/** * cpuidle_idle_call - the main idle loop * * NOTE: no locks or semaphores should be used here @@ -116,26 +181,21 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv, int cpuidle_idle_call(void) { struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices); - struct cpuidle_driver *drv; - int next_state, entered_state; + struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev); + int next_state, entered_state, ret; bool broadcast; - if (off || !initialized) - return -ENODEV; - - /* check if the device is ready */ - if (!dev || !dev->enabled) - return -EBUSY; - - drv = cpuidle_get_cpu_driver(dev); + ret = cpuidle_enabled(drv, dev); + if (ret < 0) + return ret; /* ask the governor for the next state */ - next_state = cpuidle_curr_governor->select(drv, dev); + next_state = cpuidle_select(drv, dev); + if (need_resched()) { dev->last_residency = 0; /* give the governor an opportunity to reflect on the outcome */ - if (cpuidle_curr_governor->reflect) - cpuidle_curr_governor->reflect(dev, next_state); + cpuidle_reflect(dev, next_state); local_irq_enable(); return 0; } @@ -146,14 +206,9 @@ int cpuidle_idle_call(void) clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu)) return -EBUSY; - trace_cpu_idle_rcuidle(next_state, dev->cpu); - if (cpuidle_state_is_coupled(dev, drv, next_state)) - entered_state = cpuidle_enter_state_coupled(dev, drv, - next_state); - else - entered_state = cpuidle_enter_state(dev, drv, next_state); + entered_state = cpuidle_enter(drv, dev, next_state); trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, dev->cpu); @@ -161,8 +216,7 @@ int cpuidle_idle_call(void) clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &dev->cpu); /* give the governor an opportunity to reflect on the outcome */ - if (cpuidle_curr_governor->reflect) - cpuidle_curr_governor->reflect(dev, entered_state); + cpuidle_reflect(dev, entered_state); return 0; } diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index 50fcbb0..accc2dd 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -119,6 +119,15 @@ struct cpuidle_driver { #ifdef CONFIG_CPU_IDLE extern void disable_cpuidle(void); + +extern int cpuidle_enabled(struct cpuidle_driver *drv, + struct cpuidle_device *dev); +extern int cpuidle_select(struct cpuidle_driver *drv, + struct cpuidle_device *dev); +extern int cpuidle_enter(struct cpuidle_driver *drv, + struct cpuidle_device *dev, int index); +extern void cpuidle_reflect(struct cpuidle_device *dev, int index); + extern int cpuidle_idle_call(void); extern int cpuidle_register_driver(struct cpuidle_driver *drv); extern struct cpuidle_driver *cpuidle_get_driver(void); @@ -141,6 +150,16 @@ extern int cpuidle_play_dead(void); extern struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev); #else static inline void disable_cpuidle(void) { } +static inline int cpuidle_enabled(struct cpuidle_driver *drv, + struct cpuidle_device *dev) +{return -ENODEV; } +static inline int cpuidle_select(struct cpuidle_driver *drv, + struct cpuidle_device *dev) +{return -ENODEV; } +static inline int cpuidle_enter(struct cpuidle_driver *drv, + struct cpuidle_device *dev, int index) +{return -ENODEV; } +static inline void cpuidle_reflect(struct cpuidle_device *dev, int index) { } static inline int cpuidle_idle_call(void) { return -ENODEV; } static inline int cpuidle_register_driver(struct cpuidle_driver *drv) {return -ENODEV; } |