Merge branch 'pm-cpuidle' into pm-sleep
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 8236746..cb70199 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -32,6 +32,7 @@
static int enabled_devices;
static int off __read_mostly;
static int initialized __read_mostly;
+static bool use_deepest_state __read_mostly;
int cpuidle_disabled(void)
{
@@ -65,23 +66,42 @@
}
/**
- * cpuidle_enabled - check if the cpuidle framework is ready
- * @dev: cpuidle device for this cpu
- * @drv: cpuidle driver for this cpu
+ * cpuidle_use_deepest_state - Enable/disable the "deepest idle" mode.
+ * @enable: Whether enable or disable the feature.
*
- * Return 0 on success, otherwise:
- * -NODEV : the cpuidle framework is not available
- * -EBUSY : the cpuidle framework is not initialized
+ * If the "deepest idle" mode is enabled, cpuidle will ignore the governor and
+ * always use the state with the greatest exit latency (out of the states that
+ * are not disabled).
+ *
+ * This function can only be called after cpuidle_pause() to avoid races.
*/
-int cpuidle_enabled(struct cpuidle_driver *drv, struct cpuidle_device *dev)
+void cpuidle_use_deepest_state(bool enable)
{
- if (off || !initialized)
- return -ENODEV;
+ use_deepest_state = enable;
+}
- if (!drv || !dev || !dev->enabled)
- return -EBUSY;
+/**
+ * cpuidle_find_deepest_state - Find the state of the greatest exit latency.
+ * @drv: cpuidle driver for a given CPU.
+ * @dev: cpuidle device for a given CPU.
+ */
+static int cpuidle_find_deepest_state(struct cpuidle_driver *drv,
+ struct cpuidle_device *dev)
+{
+ unsigned int latency_req = 0;
+ int i, ret = CPUIDLE_DRIVER_STATE_START - 1;
- return 0;
+ for (i = CPUIDLE_DRIVER_STATE_START; 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)
+ continue;
+
+ latency_req = s->exit_latency;
+ ret = i;
+ }
+ return ret;
}
/**
@@ -138,6 +158,15 @@
*/
int cpuidle_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
{
+ if (off || !initialized)
+ return -ENODEV;
+
+ if (!drv || !dev || !dev->enabled)
+ return -EBUSY;
+
+ if (unlikely(use_deepest_state))
+ return cpuidle_find_deepest_state(drv, dev);
+
return cpuidle_curr_governor->select(drv, dev);
}
@@ -169,7 +198,7 @@
*/
void cpuidle_reflect(struct cpuidle_device *dev, int index)
{
- if (cpuidle_curr_governor->reflect)
+ if (cpuidle_curr_governor->reflect && !unlikely(use_deepest_state))
cpuidle_curr_governor->reflect(dev, index);
}
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index 71b5232..c4f80c1 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -296,7 +296,7 @@
data->needs_update = 0;
}
- data->last_state_idx = 0;
+ data->last_state_idx = CPUIDLE_DRIVER_STATE_START - 1;
/* Special case when user has set very strict latency requirement */
if (unlikely(latency_req == 0))
@@ -311,13 +311,6 @@
data->bucket = which_bucket(data->next_timer_us);
/*
- * if the correction factor is 0 (eg first time init or cpu hotplug
- * etc), we actually want to start out with a unity factor.
- */
- if (data->correction_factor[data->bucket] == 0)
- data->correction_factor[data->bucket] = RESOLUTION * DECAY;
-
- /*
* Force the result of multiplication to be 64 bits even if both
* operands are 32 bits.
* Make sure to round up for half microseconds.
@@ -466,9 +459,17 @@
struct cpuidle_device *dev)
{
struct menu_device *data = &per_cpu(menu_devices, dev->cpu);
+ int i;
memset(data, 0, sizeof(struct menu_device));
+ /*
+ * if the correction factor is 0 (eg first time init or cpu hotplug
+ * etc), we actually want to start out with a unity factor.
+ */
+ for(i = 0; i < BUCKETS; i++)
+ data->correction_factor[i] = RESOLUTION * DECAY;
+
return 0;
}
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index b0238cb..c51a436 100644
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -120,8 +120,6 @@
#ifdef CONFIG_CPU_IDLE
extern void disable_cpuidle(void);
-extern int cpuidle_enabled(struct cpuidle_driver *drv,
- struct cpuidle_device *dev);
extern int cpuidle_select(struct cpuidle_driver *drv,
struct cpuidle_device *dev);
extern int cpuidle_enter(struct cpuidle_driver *drv,
@@ -145,13 +143,11 @@
extern int cpuidle_enable_device(struct cpuidle_device *dev);
extern void cpuidle_disable_device(struct cpuidle_device *dev);
extern int cpuidle_play_dead(void);
+extern void cpuidle_use_deepest_state(bool enable);
extern struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev);
#else
static inline void disable_cpuidle(void) { }
-static inline int cpuidle_enabled(struct cpuidle_driver *drv,
- struct cpuidle_device *dev)
-{return -ENODEV; }
static inline int cpuidle_select(struct cpuidle_driver *drv,
struct cpuidle_device *dev)
{return -ENODEV; }
@@ -180,6 +176,7 @@
{return -ENODEV; }
static inline void cpuidle_disable_device(struct cpuidle_device *dev) { }
static inline int cpuidle_play_dead(void) {return -ENODEV; }
+static inline void cpuidle_use_deepest_state(bool enable) {}
static inline struct cpuidle_driver *cpuidle_get_cpu_driver(
struct cpuidle_device *dev) {return NULL; }
#endif
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 8233cd4..155721f 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -54,9 +54,11 @@
static void freeze_enter(void)
{
+ cpuidle_use_deepest_state(true);
cpuidle_resume();
wait_event(suspend_freeze_wait_head, suspend_freeze_wake);
cpuidle_pause();
+ cpuidle_use_deepest_state(false);
}
void freeze_wake(void)
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index 8f4390a..a8f1224 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -101,19 +101,13 @@
rcu_idle_enter();
/*
- * Check if the cpuidle framework is ready, otherwise fallback
- * to the default arch specific idle method
+ * Ask the cpuidle framework to choose a convenient idle state.
+ * Fall back to the default arch specific idle method on errors.
*/
- ret = cpuidle_enabled(drv, dev);
+ next_state = cpuidle_select(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);
-
+ ret = next_state;
+ if (ret >= 0) {
/*
* The idle task must be scheduled, it is pointless to
* go to idle, just update no idle residency and get
@@ -140,7 +134,7 @@
CLOCK_EVT_NOTIFY_BROADCAST_ENTER,
&dev->cpu);
- if (!ret) {
+ if (ret >= 0) {
trace_cpu_idle_rcuidle(next_state, dev->cpu);
/*
@@ -175,7 +169,7 @@
* We can't use the cpuidle framework, let's use the default
* idle routine
*/
- if (ret)
+ if (ret < 0)
arch_cpu_idle();
__current_set_polling();