Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph...

[firefly-linux-kernel-4.4.55.git] / drivers / cpuidle / cpuidle.c

diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index cb20fd915be8cefb87c0a35a338dfedc70374a08..8236746e46bb9d5afa313aff7d17f72fd1ec2326 100644 (file)
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -64,6 +64,26 @@ int cpuidle_play_dead(void)
        return -ENODEV;
 }
 
+/**
+ * cpuidle_enabled - check if the cpuidle framework is ready
+ * @dev: cpuidle device for this cpu
+ * @drv: cpuidle driver for this cpu
+ *
+ * Return 0 on success, otherwise:
+ * -NODEV : the cpuidle framework is not available
+ * -EBUSY : the cpuidle framework is not initialized
+ */
+int cpuidle_enabled(struct cpuidle_driver *drv, struct cpuidle_device *dev)
+{
+       if (off || !initialized)
+               return -ENODEV;
+
+       if (!drv || !dev || !dev->enabled)
+               return -EBUSY;
+
+       return 0;
+}
+
 /**
  * cpuidle_enter_state - enter the state and update stats
  * @dev: cpuidle device for this cpu
@@ -109,63 +129,48 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv,
 }
 
 /**
- * cpuidle_idle_call - the main idle loop
+ * cpuidle_select - ask the cpuidle framework to choose an idle state
+ *
+ * @drv: the cpuidle driver
+ * @dev: the cpuidle device
  *
- * NOTE: no locks or semaphores should be used here
- * return non-zero on failure
+ * Returns the index of the idle state.
  */
-int cpuidle_idle_call(void)
+int cpuidle_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
 {
-       struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices);
-       struct cpuidle_driver *drv;
-       int next_state, entered_state;
-       bool broadcast;
-
-       if (off || !initialized)
-               return -ENODEV;
-
-       /* check if the device is ready */
-       if (!dev || !dev->enabled)
-               return -EBUSY;
-
-       drv = cpuidle_get_cpu_driver(dev);
-
-       /* ask the governor for the next state */
-       next_state = cpuidle_curr_governor->select(drv, dev);
-       if (need_resched()) {
-               dev->last_residency = 0;
-               /* give the governor an opportunity to reflect on the outcome */
-               if (cpuidle_curr_governor->reflect)
-                       cpuidle_curr_governor->reflect(dev, next_state);
-               local_irq_enable();
-               return 0;
-       }
-
-       broadcast = !!(drv->states[next_state].flags & CPUIDLE_FLAG_TIMER_STOP);
-
-       if (broadcast &&
-           clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu))
-               return -EBUSY;
-
-
-       trace_cpu_idle_rcuidle(next_state, dev->cpu);
-
-       if (cpuidle_state_is_coupled(dev, drv, next_state))
-               entered_state = cpuidle_enter_state_coupled(dev, drv,
-                                                           next_state);
-       else
-               entered_state = cpuidle_enter_state(dev, drv, next_state);
-
-       trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, dev->cpu);
+       return cpuidle_curr_governor->select(drv, dev);
+}
 
-       if (broadcast)
-               clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &dev->cpu);
+/**
+ * cpuidle_enter - enter into the specified idle state
+ *
+ * @drv:   the cpuidle driver tied with the cpu
+ * @dev:   the cpuidle device
+ * @index: the index in the idle state table
+ *
+ * Returns the index in the idle state, < 0 in case of error.
+ * The error code depends on the backend driver
+ */
+int cpuidle_enter(struct cpuidle_driver *drv, struct cpuidle_device *dev,
+                 int index)
+{
+       if (cpuidle_state_is_coupled(dev, drv, index))
+               return cpuidle_enter_state_coupled(dev, drv, index);
+       return cpuidle_enter_state(dev, drv, index);
+}
 
-       /* give the governor an opportunity to reflect on the outcome */
+/**
+ * cpuidle_reflect - tell the underlying governor what was the state
+ * we were in
+ *
+ * @dev  : the cpuidle device
+ * @index: the index in the idle state table
+ *
+ */
+void cpuidle_reflect(struct cpuidle_device *dev, int index)
+{
        if (cpuidle_curr_governor->reflect)
-               cpuidle_curr_governor->reflect(dev, entered_state);
-
-       return 0;
+               cpuidle_curr_governor->reflect(dev, index);
 }
 
 /**