diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c index 0f7ead6..a625f12 100644 --- a/drivers/base/power/wakeup.c +++ b/drivers/base/power/wakeup.c @@ -380,6 +380,12 @@ static void wakeup_source_activate(struct wakeup_source *ws) { unsigned int cec; + /* + * active wakeup source should bring the system + * out of PM_SUSPEND_FREEZE state + */ + freeze_wake(); + ws->active = true; ws->active_count++; ws->last_time = ktime_get(); diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 25d11c7..2ef9558 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -30,6 +30,7 @@ LIST_HEAD(cpuidle_detected_devices); static int enabled_devices; static int off __read_mostly; static int initialized __read_mostly; +static bool use_deepest_state __read_mostly; int cpuidle_disabled(void) { @@ -103,6 +104,45 @@ int cpuidle_play_dead(void) } /** + * cpuidle_use_deepest_state - Enable/disable the "deepest idle" mode. + * @enable: Whether enable or disable the feature. + * + * If the "deepest idle" mode is enabled, cpuidle will ignore the governor and + * always use the state with the greatest exit latency (out of the states that + * are not disabled). + * + * This function can only be called after cpuidle_pause() to avoid races. + */ +void cpuidle_use_deepest_state(bool enable) +{ + use_deepest_state = enable; +} + +/** + * cpuidle_find_deepest_state - Find the state of the greatest exit latency. + * @drv: cpuidle driver for a given CPU. + * @dev: cpuidle device for a given CPU. + */ +static int cpuidle_find_deepest_state(struct cpuidle_driver *drv, + struct cpuidle_device *dev) +{ + unsigned int latency_req = 0; + int i, ret = CPUIDLE_DRIVER_STATE_START - 1; + + for (i = CPUIDLE_DRIVER_STATE_START; i < drv->state_count; i++) { + struct cpuidle_state *s = &drv->states[i]; + + if (s->disable || s->exit_latency <= latency_req) + continue; + + latency_req = s->exit_latency; + ret = i; + } + printk("[suspend]: entering deepest idle state: %u", ret); + return ret; +} + +/** * cpuidle_enter_state - enter the state and update stats * @dev: cpuidle device for this cpu * @drv: cpuidle driver for this cpu @@ -152,6 +192,9 @@ int cpuidle_idle_call(void) if (!dev || !dev->enabled) return -EBUSY; + if (unlikely(use_deepest_state)) + return cpuidle_find_deepest_state(drv, dev); + #if 0 /* shows regressions, re-enable for 2.6.29 */ /* diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index 5ab7183..48808f8 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -157,6 +157,7 @@ extern int cpuidle_wrap_enter(struct cpuidle_device *dev, int (*enter)(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index)); extern int cpuidle_play_dead(void); +extern void cpuidle_use_deepest_state(bool enable); #else static inline void disable_cpuidle(void) { } @@ -180,6 +181,7 @@ static inline int cpuidle_wrap_enter(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index)) { return -ENODEV; } static inline int cpuidle_play_dead(void) {return -ENODEV; } +static inline void cpuidle_use_deepest_state(bool enable) {} #endif diff --git a/include/linux/suspend.h b/include/linux/suspend.h index cd83059..076cee6 100644 --- a/include/linux/suspend.h +++ b/include/linux/suspend.h @@ -34,8 +34,10 @@ static inline void pm_restore_console(void) typedef int __bitwise suspend_state_t; #define PM_SUSPEND_ON ((__force suspend_state_t) 0) -#define PM_SUSPEND_STANDBY ((__force suspend_state_t) 1) +#define PM_SUSPEND_FREEZE ((__force suspend_state_t) 1) +#define PM_SUSPEND_STANDBY ((__force suspend_state_t) 2) #define PM_SUSPEND_MEM ((__force suspend_state_t) 3) +#define PM_SUSPEND_MIN PM_SUSPEND_FREEZE #define PM_SUSPEND_MAX ((__force suspend_state_t) 4) enum suspend_stat_step { @@ -192,6 +194,7 @@ struct platform_suspend_ops { */ extern void suspend_set_ops(const struct platform_suspend_ops *ops); extern int suspend_valid_only_mem(suspend_state_t state); +extern void freeze_wake(void); /** * arch_suspend_disable_irqs - disable IRQs for suspend @@ -217,6 +220,7 @@ extern int pm_suspend(suspend_state_t state); static inline void suspend_set_ops(const struct platform_suspend_ops *ops) {} static inline int pm_suspend(suspend_state_t state) { return -ENOSYS; } +static inline void freeze_wake(void) {} #endif /* !CONFIG_SUSPEND */ /* struct pbe is used for creating lists of pages that should be restored diff --git a/kernel/power/main.c b/kernel/power/main.c index c64b17c..bab625c 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -360,7 +360,7 @@ static suspend_state_t decode_state(const char *buf, size_t n) #ifdef CONFIG_EARLYSUSPEND suspend_state_t state = PM_SUSPEND_ON; #else - suspend_state_t state = PM_SUSPEND_STANDBY; + suspend_state_t state = PM_SUSPEND_MIN; #endif const char * const *s; #endif diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 160d4d2..2f298b7 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -36,10 +37,38 @@ const char *const pm_states[PM_SUSPEND_MAX] = { #ifdef CONFIG_EARLYSUSPEND [PM_SUSPEND_ON] = "on", #endif + [PM_SUSPEND_FREEZE] = "freeze", [PM_SUSPEND_STANDBY] = "standby", [PM_SUSPEND_MEM] = "mem", }; +static bool need_suspend_ops(suspend_state_t state) +{ + return !!(state > PM_SUSPEND_FREEZE); +} + +static DECLARE_WAIT_QUEUE_HEAD(suspend_freeze_wait_head); +static bool suspend_freeze_wake; + +static void freeze_begin(void) +{ + suspend_freeze_wake = false; +} + +static void freeze_enter(void) +{ + cpuidle_use_deepest_state(true); + wait_event(suspend_freeze_wait_head, suspend_freeze_wake); + cpuidle_use_deepest_state(false); +} + +void freeze_wake(void) +{ + suspend_freeze_wake = true; + wake_up(&suspend_freeze_wait_head); +} +EXPORT_SYMBOL_GPL(freeze_wake); + static const struct platform_suspend_ops *suspend_ops; /** @@ -92,8 +121,11 @@ EXPORT_SYMBOL_GPL(suspend_set_ops); bool valid_state(suspend_state_t state) { + if (state == PM_SUSPEND_FREEZE) + return true; /* - * All states need lowlevel support and need to be valid to the lowlevel + * PM_SUSPEND_STANDBY and PM_SUSPEND_MEMORY states need lowlevel + * support and need to be valid to the lowlevel * implementation, no valid callback implies that none are valid. */ return suspend_ops && suspend_ops->valid && suspend_ops->valid(state); @@ -131,11 +163,11 @@ static int suspend_test(int level) * hibernation). Run suspend notifiers, allocate the "suspend" console and * freeze processes. */ -static int suspend_prepare(void) +static int suspend_prepare(suspend_state_t state) { int error; - if (!suspend_ops || !suspend_ops->enter) + if (need_suspend_ops(state) && (!suspend_ops || !suspend_ops->enter)) return -EPERM; pm_prepare_console(); @@ -179,7 +211,7 @@ static int suspend_enter(suspend_state_t state, bool *wakeup) { int error; - if (suspend_ops->prepare) { + if (need_suspend_ops(state) && suspend_ops->prepare) { error = suspend_ops->prepare(); if (error) goto Platform_finish; @@ -191,12 +223,23 @@ static int suspend_enter(suspend_state_t state, bool *wakeup) goto Platform_finish; } - if (suspend_ops->prepare_late) { + if (need_suspend_ops(state) && suspend_ops->prepare_late) { error = suspend_ops->prepare_late(); if (error) goto Platform_wake; } + /* + * PM_SUSPEND_FREEZE equals + * frozen processes + suspended devices + idle processors. + * Thus we should invoke freeze_enter() soon after + * all the devices are suspended. + */ + if (state == PM_SUSPEND_FREEZE) { + freeze_enter(); + goto Platform_wake; + } + if (suspend_test(TEST_PLATFORM)) goto Platform_wake; @@ -224,13 +267,13 @@ static int suspend_enter(suspend_state_t state, bool *wakeup) enable_nonboot_cpus(); Platform_wake: - if (suspend_ops->wake) + if (need_suspend_ops(state) && suspend_ops->wake) suspend_ops->wake(); dpm_resume_start(PMSG_RESUME); Platform_finish: - if (suspend_ops->finish) + if (need_suspend_ops(state) && suspend_ops->finish) suspend_ops->finish(); return error; @@ -245,11 +288,11 @@ int suspend_devices_and_enter(suspend_state_t state) int error; bool wakeup = false; - if (!suspend_ops) + if (need_suspend_ops(state) && !suspend_ops) return -ENOSYS; trace_machine_suspend(state); - if (suspend_ops->begin) { + if (need_suspend_ops(state) && suspend_ops->begin) { error = suspend_ops->begin(state); if (error) goto Close; @@ -267,7 +310,7 @@ int suspend_devices_and_enter(suspend_state_t state) do { error = suspend_enter(state, &wakeup); - } while (!error && !wakeup + } while (!error && !wakeup && need_suspend_ops(state) && suspend_ops->suspend_again && suspend_ops->suspend_again()); Resume_devices: @@ -276,13 +319,13 @@ int suspend_devices_and_enter(suspend_state_t state) suspend_test_finish("resume devices"); resume_console(); Close: - if (suspend_ops->end) + if (need_suspend_ops(state) && suspend_ops->end) suspend_ops->end(); trace_machine_suspend(PWR_EVENT_EXIT); return error; Recover_platform: - if (suspend_ops->recover) + if (need_suspend_ops(state) && suspend_ops->recover) suspend_ops->recover(); goto Resume_devices; } @@ -318,13 +361,16 @@ static int enter_state(suspend_state_t state) if (!mutex_trylock(&pm_mutex)) return -EBUSY; + if (state == PM_SUSPEND_FREEZE) + freeze_begin(); + printk(KERN_INFO "PM: Syncing filesystems ... "); sys_sync(); printk("done.\n"); pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); suspend_wdset(); - error = suspend_prepare(); + error = suspend_prepare(state); suspend_wdclr(); if (error) goto Unlock;