diff options
| -rw-r--r-- | drivers/cpuidle/cpuidle.c | 62 | ||||
| -rw-r--r-- | include/linux/cpuidle.h | 17 | ||||
| -rw-r--r-- | kernel/sched/idle.c | 30 |
3 files changed, 58 insertions, 51 deletions
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 8b3e132..080bd2d 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -44,8 +44,8 @@ void disable_cpuidle(void) off = 1; } -static bool cpuidle_not_available(struct cpuidle_driver *drv, - struct cpuidle_device *dev) +bool cpuidle_not_available(struct cpuidle_driver *drv, + struct cpuidle_device *dev) { return off || !initialized || !drv || !dev || !dev->enabled; } @@ -72,14 +72,8 @@ int cpuidle_play_dead(void) return -ENODEV; } -/** - * cpuidle_find_deepest_state - Find deepest state meeting specific conditions. - * @drv: cpuidle driver for the given CPU. - * @dev: cpuidle device for the given CPU. - * @freeze: Whether or not the state should be suitable for suspend-to-idle. - */ -static int cpuidle_find_deepest_state(struct cpuidle_driver *drv, - struct cpuidle_device *dev, bool freeze) +static int find_deepest_state(struct cpuidle_driver *drv, + struct cpuidle_device *dev, bool freeze) { unsigned int latency_req = 0; int i, ret = freeze ? -1 : CPUIDLE_DRIVER_STATE_START - 1; @@ -98,6 +92,17 @@ static int cpuidle_find_deepest_state(struct cpuidle_driver *drv, return ret; } +/** + * cpuidle_find_deepest_state - Find the deepest available idle state. + * @drv: cpuidle driver for the given CPU. + * @dev: cpuidle device for the given CPU. + */ +int cpuidle_find_deepest_state(struct cpuidle_driver *drv, + struct cpuidle_device *dev) +{ + return find_deepest_state(drv, dev, false); +} + static void enter_freeze_proper(struct cpuidle_driver *drv, struct cpuidle_device *dev, int index) { @@ -119,46 +124,26 @@ static void enter_freeze_proper(struct cpuidle_driver *drv, /** * cpuidle_enter_freeze - Enter an idle state suitable for suspend-to-idle. + * @drv: cpuidle driver for the given CPU. + * @dev: cpuidle device for the given CPU. * * If there are states with the ->enter_freeze callback, find the deepest of - * them and enter it with frozen tick. Otherwise, find the deepest state - * available and enter it normally. - * - * Returns with enabled interrupts. + * them and enter it with frozen tick. */ -void cpuidle_enter_freeze(void) +int cpuidle_enter_freeze(struct cpuidle_driver *drv, struct cpuidle_device *dev) { - struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices); - struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev); int index; - if (cpuidle_not_available(drv, dev)) - goto fallback; - /* * Find the deepest state with ->enter_freeze present, which guarantees * that interrupts won't be enabled when it exits and allows the tick to * be frozen safely. */ - index = cpuidle_find_deepest_state(drv, dev, true); - if (index >= 0) { + index = find_deepest_state(drv, dev, true); + if (index >= 0) enter_freeze_proper(drv, dev, index); - local_irq_enable(); - return; - } - /* - * It is not safe to freeze the tick, find the deepest state available - * at all and try to enter it normally. - */ - index = cpuidle_find_deepest_state(drv, dev, false); - if (index >= 0) { - cpuidle_enter(drv, dev, index); - return; - } - - fallback: - arch_cpu_idle(); + return index; } /** @@ -217,9 +202,6 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv, */ int cpuidle_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) { - if (cpuidle_not_available(drv, dev)) - return -ENODEV; - return cpuidle_curr_governor->select(drv, dev); } diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index f551a92..306178d 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -126,6 +126,8 @@ struct cpuidle_driver { #ifdef CONFIG_CPU_IDLE extern void disable_cpuidle(void); +extern bool cpuidle_not_available(struct cpuidle_driver *drv, + struct cpuidle_device *dev); extern int cpuidle_select(struct cpuidle_driver *drv, struct cpuidle_device *dev); @@ -150,11 +152,17 @@ extern void cpuidle_resume(void); extern int cpuidle_enable_device(struct cpuidle_device *dev); extern void cpuidle_disable_device(struct cpuidle_device *dev); extern int cpuidle_play_dead(void); -extern void cpuidle_enter_freeze(void); +extern int cpuidle_find_deepest_state(struct cpuidle_driver *drv, + struct cpuidle_device *dev); +extern int cpuidle_enter_freeze(struct cpuidle_driver *drv, + struct cpuidle_device *dev); extern struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev); #else static inline void disable_cpuidle(void) { } +static inline bool cpuidle_not_available(struct cpuidle_driver *drv, + struct cpuidle_device *dev) +{return true; } static inline int cpuidle_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) {return -ENODEV; } @@ -183,7 +191,12 @@ static inline int cpuidle_enable_device(struct cpuidle_device *dev) {return -ENODEV; } static inline void cpuidle_disable_device(struct cpuidle_device *dev) { } static inline int cpuidle_play_dead(void) {return -ENODEV; } -static inline void cpuidle_enter_freeze(void) { } +static inline int cpuidle_find_deepest_state(struct cpuidle_driver *drv, + struct cpuidle_device *dev) +{return -ENODEV; } +static inline int cpuidle_enter_freeze(struct cpuidle_driver *drv, + struct cpuidle_device *dev) +{return -ENODEV; } static inline struct cpuidle_driver *cpuidle_get_cpu_driver( struct cpuidle_device *dev) {return NULL; } #endif diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c index 84b93b6..80014a1 100644 --- a/kernel/sched/idle.c +++ b/kernel/sched/idle.c @@ -82,6 +82,7 @@ static void cpuidle_idle_call(void) struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev); int next_state, entered_state; unsigned int broadcast; + bool reflect; /* * Check if the idle task must be rescheduled. If it is the @@ -105,6 +106,9 @@ static void cpuidle_idle_call(void) */ rcu_idle_enter(); + if (cpuidle_not_available(drv, dev)) + goto use_default; + /* * Suspend-to-idle ("freeze") is a system state in which all user space * has been frozen, all I/O devices have been suspended and the only @@ -115,15 +119,22 @@ static void cpuidle_idle_call(void) * until a proper wakeup interrupt happens. */ if (idle_should_freeze()) { - cpuidle_enter_freeze(); - goto exit_idle; - } + entered_state = cpuidle_enter_freeze(drv, dev); + if (entered_state >= 0) { + local_irq_enable(); + goto exit_idle; + } - /* - * Ask the cpuidle framework to choose a convenient idle state. - * Fall back to the default arch idle method on errors. - */ - next_state = cpuidle_select(drv, dev); + reflect = false; + next_state = cpuidle_find_deepest_state(drv, dev); + } else { + reflect = true; + /* + * Ask the cpuidle framework to choose a convenient idle state. + */ + next_state = cpuidle_select(drv, dev); + } + /* Fall back to the default arch idle method on errors. */ if (next_state < 0) goto use_default; @@ -170,7 +181,8 @@ static void cpuidle_idle_call(void) /* * Give the governor an opportunity to reflect on the outcome */ - cpuidle_reflect(dev, entered_state); + if (reflect) + cpuidle_reflect(dev, entered_state); exit_idle: __current_set_polling(); |