Encapsulate the large portion of cpuidle_idle_call inside another
function so when CONFIG_CPU_IDLE=n, the code will be compiled out.
Also that is benefitial for the clarity of the code as it removes
a nested indentation level.
Signed-off-by: Daniel Lezcano <daniel.lezc...@linaro.org>
---
kernel/sched/idle.c | 161 +++++++++++++++++++++++++++------------------------
1 file changed, 86 insertions(+), 75 deletions(-)
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index b8cd302..f2f4bc9 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -63,6 +63,90 @@ void __weak arch_cpu_idle(void)
local_irq_enable();
}
+#ifdef CONFIG_CPU_IDLE
+static int __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, ret;
+ bool broadcast;
+
+ /*
+ * Check if the cpuidle framework is ready, otherwise fallback
+ * to the default arch specific idle method
+ */
+ ret = cpuidle_enabled(drv, dev);
+ if (ret)
+ return ret;
+
+ /*
+ * Ask the governor to choose an idle state it thinks
+ * it is convenient to go to. There is *always* a
+ * convenient idle state
+ */
+ next_state = cpuidle_select(drv, dev);
+
+ /*
+ * 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();
+ } else {
+ broadcast = !!(drv->states[next_state].flags &
+ CPUIDLE_FLAG_TIMER_STOP);
+
+ if (broadcast)
+ /*
+ * Tell the time framework to switch to a
+ * broadcast timer because our local timer
+ * will be shutdown. If a local timer is used
+ * from another cpu as a broadcast timer, this
+ * call may fail if it is not available
+ */
+ ret = clockevents_notify(
+ CLOCK_EVT_NOTIFY_BROADCAST_ENTER,
+ &dev->cpu);
+
+ if (!ret) {
+ trace_cpu_idle_rcuidle(next_state, dev->cpu);
+
+ /*
+ * 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);
+
+ trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, dev->cpu);
+
+ if (broadcast)
+ clockevents_notify(
+ CLOCK_EVT_NOTIFY_BROADCAST_EXIT,
+ &dev->cpu);
+
+ /*
+ * Give the governor an opportunity to reflect
+ * on the outcome
+ */
+ cpuidle_reflect(dev, entered_state);
+ }
+ }
+
+ return 0;
+}
+#else
+static int inline __cpuidle_idle_call(void)
+{
+ return -ENOSYS;
+}
+#endif
+
/**
* cpuidle_idle_call - the main idle function
*
@@ -70,10 +154,7 @@ void __weak arch_cpu_idle(void)
*/
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, ret;
- bool broadcast;
+ int ret;
/*
* Check if the idle task must be rescheduled. If it is the
@@ -100,80 +181,10 @@ static void cpuidle_idle_call(void)
rcu_idle_enter();
/*
- * Check if the cpuidle framework is ready, otherwise fallback
- * to the default arch specific idle method
- */
- ret = cpuidle_enabled(drv, dev);
-
- if (!ret) {
- /*
- * Ask the governor to choose an idle state it thinks
- * it is convenient to go to. There is *always* a
- * convenient idle state
- */
- next_state = cpuidle_select(drv, dev);
-
- /*
- * 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();
- } else {
- broadcast = !!(drv->states[next_state].flags &
- CPUIDLE_FLAG_TIMER_STOP);
-
- if (broadcast)
- /*
- * Tell the time framework to switch
- * to a broadcast timer because our
- * local timer will be shutdown. If a
- * local timer is used from another
- * cpu as a broadcast timer, this call
- * may fail if it is not available
- */
- ret = clockevents_notify(
- CLOCK_EVT_NOTIFY_BROADCAST_ENTER,
- &dev->cpu);
-
- if (!ret) {
- trace_cpu_idle_rcuidle(next_state, dev->cpu);
-
- /*
- * 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);
-
- trace_cpu_idle_rcuidle(PWR_EVENT_EXIT,
- dev->cpu);
-
- if (broadcast)
- clockevents_notify(
- CLOCK_EVT_NOTIFY_BROADCAST_EXIT,
- &dev->cpu);
-
- /*
- * Give the governor an opportunity to reflect
on the
- * outcome
- */
- cpuidle_reflect(dev, entered_state);
- }
- }
- }
-
- /*
* We can't use the cpuidle framework, let's use the default
* idle routine
*/
+ ret = __cpuidle_idle_call();
if (ret)
arch_cpu_idle();
--
1.7.9.5
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