return -ENODEV;
/* Find lowest-power state that supports long-term idle */
- for (i = drv->state_count - 1; i >= CPUIDLE_DRIVER_STATE_START; i--)
+ for (i = drv->state_count - 1; i >= 0; i--)
if (drv->states[i].enter_dead)
return drv->states[i].enter_dead(dev, i);
}
static int find_deepest_state(struct cpuidle_driver *drv,
- struct cpuidle_device *dev, bool freeze)
+ struct cpuidle_device *dev,
+ unsigned int max_latency,
+ unsigned int forbidden_flags,
+ bool freeze)
{
unsigned int latency_req = 0;
- int i, ret = freeze ? -1 : CPUIDLE_DRIVER_STATE_START - 1;
+ int i, ret = -ENXIO;
- for (i = CPUIDLE_DRIVER_STATE_START; i < drv->state_count; i++) {
+ for (i = 0; i < drv->state_count; i++) {
struct cpuidle_state *s = &drv->states[i];
struct cpuidle_state_usage *su = &dev->states_usage[i];
if (s->disabled || su->disable || s->exit_latency <= latency_req
+ || s->exit_latency > max_latency
+ || (s->flags & forbidden_flags)
|| (freeze && !s->enter_freeze))
continue;
return ret;
}
+#ifdef CONFIG_SUSPEND
/**
* cpuidle_find_deepest_state - Find the deepest available idle state.
* @drv: cpuidle driver for the given CPU.
int cpuidle_find_deepest_state(struct cpuidle_driver *drv,
struct cpuidle_device *dev)
{
- return find_deepest_state(drv, dev, false);
+ return find_deepest_state(drv, dev, UINT_MAX, 0, false);
}
static void enter_freeze_proper(struct cpuidle_driver *drv,
struct cpuidle_device *dev, int index)
{
- tick_freeze();
+ /*
+ * trace_suspend_resume() called by tick_freeze() for the last CPU
+ * executing it contains RCU usage regarded as invalid in the idle
+ * context, so tell RCU about that.
+ */
+ RCU_NONIDLE(tick_freeze());
/*
* The state used here cannot be a "coupled" one, because the "coupled"
* cpuidle mechanism enables interrupts and doing that with timekeeping
* suspended is generally unsafe.
*/
+ stop_critical_timings();
drv->states[index].enter_freeze(dev, drv, index);
WARN_ON(!irqs_disabled());
/*
* timekeeping_resume() that will be called by tick_unfreeze() for the
- * last CPU executing it calls functions containing RCU read-side
+ * first CPU executing it calls functions containing RCU read-side
* critical sections, so tell RCU about that.
*/
RCU_NONIDLE(tick_unfreeze());
+ start_critical_timings();
}
/**
* that interrupts won't be enabled when it exits and allows the tick to
* be frozen safely.
*/
- index = find_deepest_state(drv, dev, true);
+ index = find_deepest_state(drv, dev, UINT_MAX, 0, true);
if (index >= 0)
enter_freeze_proper(drv, dev, index);
return index;
}
+#endif /* CONFIG_SUSPEND */
/**
* cpuidle_enter_state - enter the state and update stats
* @dev: cpuidle device for this cpu
* @drv: cpuidle driver for this cpu
- * @next_state: index into drv->states of the state to enter
+ * @index: index into the states table in @drv of the state to enter
*/
int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv,
int index)
* local timer will be shut down. If a local timer is used from another
* CPU as a broadcast timer, this call may fail if it is not available.
*/
- if (broadcast && tick_broadcast_enter())
- return -EBUSY;
+ if (broadcast && tick_broadcast_enter()) {
+ index = find_deepest_state(drv, dev, target_state->exit_latency,
+ CPUIDLE_FLAG_TIMER_STOP, false);
+ if (index < 0) {
+ default_idle_call();
+ return -EBUSY;
+ }
+ target_state = &drv->states[index];
+ }
+
+ /* Take note of the planned idle state. */
+ sched_idle_set_state(target_state);
trace_cpu_idle_rcuidle(index, dev->cpu);
time_start = ktime_get();
+ stop_critical_timings();
entered_state = target_state->enter(dev, drv, index);
+ start_critical_timings();
time_end = ktime_get();
trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, dev->cpu);
+ /* The cpu is no longer idle or about to enter idle. */
+ sched_idle_set_state(NULL);
+
if (broadcast) {
if (WARN_ON_ONCE(!irqs_disabled()))
local_irq_disable();
tick_broadcast_exit();
}
- if (!cpuidle_state_is_coupled(dev, drv, entered_state))
+ if (!cpuidle_state_is_coupled(drv, entered_state))
local_irq_enable();
diff = ktime_to_us(ktime_sub(time_end, time_start));
int cpuidle_enter(struct cpuidle_driver *drv, struct cpuidle_device *dev,
int index)
{
- if (cpuidle_state_is_coupled(dev, drv, index))
+ if (cpuidle_state_is_coupled(drv, index))
return cpuidle_enter_state_coupled(dev, drv, index);
return cpuidle_enter_state(dev, drv, index);
}
*/
void cpuidle_reflect(struct cpuidle_device *dev, int index)
{
- if (cpuidle_curr_governor->reflect)
+ if (cpuidle_curr_governor->reflect && index >= 0)
cpuidle_curr_governor->reflect(dev, index);
}
Code Review / kvmfornfv.git / blobdiff