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Diffstat (limited to 'kernel/sched/idle.c')
-rw-r--r--kernel/sched/idle.c114
1 files changed, 59 insertions, 55 deletions
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index fefcb1fa5160..594275ed2620 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -15,6 +15,15 @@
#include "sched.h"
+/**
+ * sched_idle_set_state - Record idle state for the current CPU.
+ * @idle_state: State to record.
+ */
+void sched_idle_set_state(struct cpuidle_state *idle_state)
+{
+ idle_set_state(this_rq(), idle_state);
+}
+
static int __read_mostly cpu_idle_force_poll;
void cpu_idle_poll_ctrl(bool enable)
@@ -68,6 +77,46 @@ void __weak arch_cpu_idle(void)
}
/**
+ * default_idle_call - Default CPU idle routine.
+ *
+ * To use when the cpuidle framework cannot be used.
+ */
+void default_idle_call(void)
+{
+ if (current_clr_polling_and_test())
+ local_irq_enable();
+ else
+ arch_cpu_idle();
+}
+
+static int call_cpuidle(struct cpuidle_driver *drv, struct cpuidle_device *dev,
+ int next_state)
+{
+ /* Fall back to the default arch idle method on errors. */
+ if (next_state < 0) {
+ default_idle_call();
+ return next_state;
+ }
+
+ /*
+ * The idle task must be scheduled, it is pointless to go to idle, just
+ * update no idle residency and return.
+ */
+ if (current_clr_polling_and_test()) {
+ dev->last_residency = 0;
+ local_irq_enable();
+ return -EBUSY;
+ }
+
+ /*
+ * Enter the idle state previously returned by the governor decision.
+ * This function will block until an interrupt occurs and will take
+ * care of re-enabling the local interrupts
+ */
+ return cpuidle_enter(drv, dev, next_state);
+}
+
+/**
* cpuidle_idle_call - the main idle function
*
* NOTE: no locks or semaphores should be used here
@@ -81,7 +130,6 @@ static void cpuidle_idle_call(void)
struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices);
struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev);
int next_state, entered_state;
- bool reflect;
/*
* Check if the idle task must be rescheduled. If it is the
@@ -105,8 +153,10 @@ static void cpuidle_idle_call(void)
*/
rcu_idle_enter();
- if (cpuidle_not_available(drv, dev))
- goto use_default;
+ if (cpuidle_not_available(drv, dev)) {
+ default_idle_call();
+ goto exit_idle;
+ }
/*
* Suspend-to-idle ("freeze") is a system state in which all user space
@@ -124,52 +174,19 @@ static void cpuidle_idle_call(void)
goto exit_idle;
}
- reflect = false;
next_state = cpuidle_find_deepest_state(drv, dev);
+ call_cpuidle(drv, dev, next_state);
} 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;
-
- /*
- * The idle task must be scheduled, it is pointless to
- * go to idle, just update no idle residency and get
- * out of this function
- */
- if (current_clr_polling_and_test()) {
- dev->last_residency = 0;
- entered_state = next_state;
- local_irq_enable();
- goto exit_idle;
- }
-
- /* Take note of the planned idle state. */
- idle_set_state(this_rq(), &drv->states[next_state]);
-
- /*
- * Enter the idle state previously returned by the governor decision.
- * This function will block until an interrupt occurs and will take
- * care of re-enabling the local interrupts
- */
- entered_state = cpuidle_enter(drv, dev, next_state);
-
- /* The cpu is no longer idle or about to enter idle. */
- idle_set_state(this_rq(), NULL);
-
- if (entered_state == -EBUSY)
- goto use_default;
-
- /*
- * Give the governor an opportunity to reflect on the outcome
- */
- if (reflect)
+ entered_state = call_cpuidle(drv, dev, next_state);
+ /*
+ * Give the governor an opportunity to reflect on the outcome
+ */
cpuidle_reflect(dev, entered_state);
+ }
exit_idle:
__current_set_polling();
@@ -182,19 +199,6 @@ exit_idle:
rcu_idle_exit();
start_critical_timings();
- return;
-
-use_default:
- /*
- * We can't use the cpuidle framework, let's use the default
- * idle routine.
- */
- if (current_clr_polling_and_test())
- local_irq_enable();
- else
- arch_cpu_idle();
-
- goto exit_idle;
}
DEFINE_PER_CPU(bool, cpu_dead_idle);