diff options
Diffstat (limited to 'drivers/cpuidle/cpuidle.c')
-rw-r--r-- | drivers/cpuidle/cpuidle.c | 139 |
1 files changed, 61 insertions, 78 deletions
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index bf5092455a8f..06ce2680d00d 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -12,11 +12,12 @@ #include <linux/mutex.h> #include <linux/sched.h> #include <linux/notifier.h> -#include <linux/pm_qos_params.h> +#include <linux/pm_qos.h> #include <linux/cpu.h> #include <linux/cpuidle.h> #include <linux/ktime.h> #include <linux/hrtimer.h> +#include <linux/module.h> #include <trace/events/power.h> #include "cpuidle.h" @@ -25,9 +26,19 @@ DEFINE_PER_CPU(struct cpuidle_device *, cpuidle_devices); DEFINE_MUTEX(cpuidle_lock); LIST_HEAD(cpuidle_detected_devices); -static void (*pm_idle_old)(void); static int enabled_devices; +static int off __read_mostly; +static int initialized __read_mostly; + +int cpuidle_disabled(void) +{ + return off; +} +void disable_cpuidle(void) +{ + off = 1; +} #if defined(CONFIG_ARCH_HAS_CPU_IDLE_WAIT) static void cpuidle_kick_cpus(void) @@ -46,25 +57,24 @@ static int __cpuidle_register_device(struct cpuidle_device *dev); * cpuidle_idle_call - the main idle loop * * NOTE: no locks or semaphores should be used here + * return non-zero on failure */ -static void cpuidle_idle_call(void) +int cpuidle_idle_call(void) { struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices); + struct cpuidle_driver *drv = cpuidle_get_driver(); struct cpuidle_state *target_state; - int next_state; + int next_state, entered_state; + + if (off) + return -ENODEV; + + if (!initialized) + return -ENODEV; /* check if the device is ready */ - if (!dev || !dev->enabled) { - if (pm_idle_old) - pm_idle_old(); - else -#if defined(CONFIG_ARCH_HAS_DEFAULT_IDLE) - default_idle(); -#else - local_irq_enable(); -#endif - return; - } + if (!dev || !dev->enabled) + return -EBUSY; #if 0 /* shows regressions, re-enable for 2.6.29 */ @@ -75,45 +85,38 @@ static void cpuidle_idle_call(void) hrtimer_peek_ahead_timers(); #endif - /* - * Call the device's prepare function before calling the - * governor's select function. ->prepare gives the device's - * cpuidle driver a chance to update any dynamic information - * of its cpuidle states for the current idle period, e.g. - * state availability, latencies, residencies, etc. - */ - if (dev->prepare) - dev->prepare(dev); - /* ask the governor for the next state */ - next_state = cpuidle_curr_governor->select(dev); + next_state = cpuidle_curr_governor->select(drv, dev); if (need_resched()) { local_irq_enable(); - return; + return 0; } - target_state = &dev->states[next_state]; - - /* enter the state and update stats */ - dev->last_state = target_state; + target_state = &drv->states[next_state]; trace_power_start(POWER_CSTATE, next_state, dev->cpu); trace_cpu_idle(next_state, dev->cpu); - dev->last_residency = target_state->enter(dev, target_state); + entered_state = target_state->enter(dev, drv, next_state); trace_power_end(dev->cpu); trace_cpu_idle(PWR_EVENT_EXIT, dev->cpu); - if (dev->last_state) - target_state = dev->last_state; - - target_state->time += (unsigned long long)dev->last_residency; - target_state->usage++; + if (entered_state >= 0) { + /* Update cpuidle counters */ + /* This can be moved to within driver enter routine + * but that results in multiple copies of same code. + */ + dev->states_usage[entered_state].time += + (unsigned long long)dev->last_residency; + dev->states_usage[entered_state].usage++; + } /* give the governor an opportunity to reflect on the outcome */ if (cpuidle_curr_governor->reflect) - cpuidle_curr_governor->reflect(dev); + cpuidle_curr_governor->reflect(dev, entered_state); + + return 0; } /** @@ -121,10 +124,10 @@ static void cpuidle_idle_call(void) */ void cpuidle_install_idle_handler(void) { - if (enabled_devices && (pm_idle != cpuidle_idle_call)) { + if (enabled_devices) { /* Make sure all changes finished before we switch to new idle */ smp_wmb(); - pm_idle = cpuidle_idle_call; + initialized = 1; } } @@ -133,8 +136,8 @@ void cpuidle_install_idle_handler(void) */ void cpuidle_uninstall_idle_handler(void) { - if (enabled_devices && pm_idle_old && (pm_idle != pm_idle_old)) { - pm_idle = pm_idle_old; + if (enabled_devices) { + initialized = 0; cpuidle_kick_cpus(); } } @@ -162,11 +165,11 @@ void cpuidle_resume_and_unlock(void) EXPORT_SYMBOL_GPL(cpuidle_resume_and_unlock); #ifdef CONFIG_ARCH_HAS_CPU_RELAX -static int poll_idle(struct cpuidle_device *dev, struct cpuidle_state *st) +static int poll_idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) { ktime_t t1, t2; s64 diff; - int ret; t1 = ktime_get(); local_irq_enable(); @@ -178,15 +181,14 @@ static int poll_idle(struct cpuidle_device *dev, struct cpuidle_state *st) if (diff > INT_MAX) diff = INT_MAX; - ret = (int) diff; - return ret; + dev->last_residency = (int) diff; + + return index; } -static void poll_idle_init(struct cpuidle_device *dev) +static void poll_idle_init(struct cpuidle_driver *drv) { - struct cpuidle_state *state = &dev->states[0]; - - cpuidle_set_statedata(state, NULL); + struct cpuidle_state *state = &drv->states[0]; snprintf(state->name, CPUIDLE_NAME_LEN, "POLL"); snprintf(state->desc, CPUIDLE_DESC_LEN, "CPUIDLE CORE POLL IDLE"); @@ -197,7 +199,7 @@ static void poll_idle_init(struct cpuidle_device *dev) state->enter = poll_idle; } #else -static void poll_idle_init(struct cpuidle_device *dev) {} +static void poll_idle_init(struct cpuidle_driver *drv) {} #endif /* CONFIG_ARCH_HAS_CPU_RELAX */ /** @@ -224,21 +226,20 @@ int cpuidle_enable_device(struct cpuidle_device *dev) return ret; } - poll_idle_init(dev); + poll_idle_init(cpuidle_get_driver()); if ((ret = cpuidle_add_state_sysfs(dev))) return ret; if (cpuidle_curr_governor->enable && - (ret = cpuidle_curr_governor->enable(dev))) + (ret = cpuidle_curr_governor->enable(cpuidle_get_driver(), dev))) goto fail_sysfs; for (i = 0; i < dev->state_count; i++) { - dev->states[i].usage = 0; - dev->states[i].time = 0; + dev->states_usage[i].usage = 0; + dev->states_usage[i].time = 0; } dev->last_residency = 0; - dev->last_state = NULL; smp_wmb(); @@ -272,7 +273,7 @@ void cpuidle_disable_device(struct cpuidle_device *dev) dev->enabled = 0; if (cpuidle_curr_governor->disable) - cpuidle_curr_governor->disable(dev); + cpuidle_curr_governor->disable(cpuidle_get_driver(), dev); cpuidle_remove_state_sysfs(dev); enabled_devices--; @@ -300,26 +301,6 @@ static int __cpuidle_register_device(struct cpuidle_device *dev) init_completion(&dev->kobj_unregister); - /* - * cpuidle driver should set the dev->power_specified bit - * before registering the device if the driver provides - * power_usage numbers. - * - * For those devices whose ->power_specified is not set, - * we fill in power_usage with decreasing values as the - * cpuidle code has an implicit assumption that state Cn - * uses less power than C(n-1). - * - * With CONFIG_ARCH_HAS_CPU_RELAX, C0 is already assigned - * an power value of -1. So we use -2, -3, etc, for other - * c-states. - */ - if (!dev->power_specified) { - int i; - for (i = CPUIDLE_DRIVER_STATE_START; i < dev->state_count; i++) - dev->states[i].power_usage = -1 - i; - } - per_cpu(cpuidle_devices, dev->cpu) = dev; list_add(&dev->device_list, &cpuidle_detected_devices); if ((ret = cpuidle_add_sysfs(sys_dev))) { @@ -427,7 +408,8 @@ static int __init cpuidle_init(void) { int ret; - pm_idle_old = pm_idle; + if (cpuidle_disabled()) + return -ENODEV; ret = cpuidle_add_class_sysfs(&cpu_sysdev_class); if (ret) @@ -438,4 +420,5 @@ static int __init cpuidle_init(void) return 0; } +module_param(off, int, 0444); core_initcall(cpuidle_init); |