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-rw-r--r--kernel/time/tick-broadcast.c179
1 files changed, 96 insertions, 83 deletions
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 066f0ec05e48..7e8ca4f448a8 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -33,12 +33,14 @@ static cpumask_var_t tick_broadcast_mask;
static cpumask_var_t tick_broadcast_on;
static cpumask_var_t tmpmask;
static DEFINE_RAW_SPINLOCK(tick_broadcast_lock);
-static int tick_broadcast_force;
+static int tick_broadcast_forced;
#ifdef CONFIG_TICK_ONESHOT
static void tick_broadcast_clear_oneshot(int cpu);
+static void tick_resume_broadcast_oneshot(struct clock_event_device *bc);
#else
static inline void tick_broadcast_clear_oneshot(int cpu) { }
+static inline void tick_resume_broadcast_oneshot(struct clock_event_device *bc) { }
#endif
/*
@@ -303,7 +305,7 @@ static void tick_handle_periodic_broadcast(struct clock_event_device *dev)
/*
* The device is in periodic mode. No reprogramming necessary:
*/
- if (dev->mode == CLOCK_EVT_MODE_PERIODIC)
+ if (dev->state == CLOCK_EVT_STATE_PERIODIC)
goto unlock;
/*
@@ -324,49 +326,54 @@ unlock:
raw_spin_unlock(&tick_broadcast_lock);
}
-/*
- * Powerstate information: The system enters/leaves a state, where
- * affected devices might stop
+/**
+ * tick_broadcast_control - Enable/disable or force broadcast mode
+ * @mode: The selected broadcast mode
+ *
+ * Called when the system enters a state where affected tick devices
+ * might stop. Note: TICK_BROADCAST_FORCE cannot be undone.
+ *
+ * Called with interrupts disabled, so clockevents_lock is not
+ * required here because the local clock event device cannot go away
+ * under us.
*/
-static void tick_do_broadcast_on_off(unsigned long *reason)
+void tick_broadcast_control(enum tick_broadcast_mode mode)
{
struct clock_event_device *bc, *dev;
struct tick_device *td;
- unsigned long flags;
int cpu, bc_stopped;
- raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
-
- cpu = smp_processor_id();
- td = &per_cpu(tick_cpu_device, cpu);
+ td = this_cpu_ptr(&tick_cpu_device);
dev = td->evtdev;
- bc = tick_broadcast_device.evtdev;
/*
* Is the device not affected by the powerstate ?
*/
if (!dev || !(dev->features & CLOCK_EVT_FEAT_C3STOP))
- goto out;
+ return;
if (!tick_device_is_functional(dev))
- goto out;
+ return;
+ raw_spin_lock(&tick_broadcast_lock);
+ cpu = smp_processor_id();
+ bc = tick_broadcast_device.evtdev;
bc_stopped = cpumask_empty(tick_broadcast_mask);
- switch (*reason) {
- case CLOCK_EVT_NOTIFY_BROADCAST_ON:
- case CLOCK_EVT_NOTIFY_BROADCAST_FORCE:
+ switch (mode) {
+ case TICK_BROADCAST_FORCE:
+ tick_broadcast_forced = 1;
+ case TICK_BROADCAST_ON:
cpumask_set_cpu(cpu, tick_broadcast_on);
if (!cpumask_test_and_set_cpu(cpu, tick_broadcast_mask)) {
if (tick_broadcast_device.mode ==
TICKDEV_MODE_PERIODIC)
clockevents_shutdown(dev);
}
- if (*reason == CLOCK_EVT_NOTIFY_BROADCAST_FORCE)
- tick_broadcast_force = 1;
break;
- case CLOCK_EVT_NOTIFY_BROADCAST_OFF:
- if (tick_broadcast_force)
+
+ case TICK_BROADCAST_OFF:
+ if (tick_broadcast_forced)
break;
cpumask_clear_cpu(cpu, tick_broadcast_on);
if (!tick_device_is_functional(dev))
@@ -388,22 +395,9 @@ static void tick_do_broadcast_on_off(unsigned long *reason)
else
tick_broadcast_setup_oneshot(bc);
}
-out:
- raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
-}
-
-/*
- * Powerstate information: The system enters/leaves a state, where
- * affected devices might stop.
- */
-void tick_broadcast_on_off(unsigned long reason, int *oncpu)
-{
- if (!cpumask_test_cpu(*oncpu, cpu_online_mask))
- printk(KERN_ERR "tick-broadcast: ignoring broadcast for "
- "offline CPU #%d\n", *oncpu);
- else
- tick_do_broadcast_on_off(&reason);
+ raw_spin_unlock(&tick_broadcast_lock);
}
+EXPORT_SYMBOL_GPL(tick_broadcast_control);
/*
* Set the periodic handler depending on broadcast on/off
@@ -416,14 +410,14 @@ void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast)
dev->event_handler = tick_handle_periodic_broadcast;
}
+#ifdef CONFIG_HOTPLUG_CPU
/*
* Remove a CPU from broadcasting
*/
-void tick_shutdown_broadcast(unsigned int *cpup)
+void tick_shutdown_broadcast(unsigned int cpu)
{
struct clock_event_device *bc;
unsigned long flags;
- unsigned int cpu = *cpup;
raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
@@ -438,6 +432,7 @@ void tick_shutdown_broadcast(unsigned int *cpup)
raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
}
+#endif
void tick_suspend_broadcast(void)
{
@@ -453,38 +448,48 @@ void tick_suspend_broadcast(void)
raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
}
-int tick_resume_broadcast(void)
+/*
+ * This is called from tick_resume_local() on a resuming CPU. That's
+ * called from the core resume function, tick_unfreeze() and the magic XEN
+ * resume hackery.
+ *
+ * In none of these cases the broadcast device mode can change and the
+ * bit of the resuming CPU in the broadcast mask is safe as well.
+ */
+bool tick_resume_check_broadcast(void)
+{
+ if (tick_broadcast_device.mode == TICKDEV_MODE_ONESHOT)
+ return false;
+ else
+ return cpumask_test_cpu(smp_processor_id(), tick_broadcast_mask);
+}
+
+void tick_resume_broadcast(void)
{
struct clock_event_device *bc;
unsigned long flags;
- int broadcast = 0;
raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
bc = tick_broadcast_device.evtdev;
if (bc) {
- clockevents_set_mode(bc, CLOCK_EVT_MODE_RESUME);
+ clockevents_tick_resume(bc);
switch (tick_broadcast_device.mode) {
case TICKDEV_MODE_PERIODIC:
if (!cpumask_empty(tick_broadcast_mask))
tick_broadcast_start_periodic(bc);
- broadcast = cpumask_test_cpu(smp_processor_id(),
- tick_broadcast_mask);
break;
case TICKDEV_MODE_ONESHOT:
if (!cpumask_empty(tick_broadcast_mask))
- broadcast = tick_resume_broadcast_oneshot(bc);
+ tick_resume_broadcast_oneshot(bc);
break;
}
}
raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
-
- return broadcast;
}
-
#ifdef CONFIG_TICK_ONESHOT
static cpumask_var_t tick_broadcast_oneshot_mask;
@@ -532,8 +537,8 @@ static int tick_broadcast_set_event(struct clock_event_device *bc, int cpu,
{
int ret;
- if (bc->mode != CLOCK_EVT_MODE_ONESHOT)
- clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT);
+ if (bc->state != CLOCK_EVT_STATE_ONESHOT)
+ clockevents_set_state(bc, CLOCK_EVT_STATE_ONESHOT);
ret = clockevents_program_event(bc, expires, force);
if (!ret)
@@ -541,10 +546,9 @@ static int tick_broadcast_set_event(struct clock_event_device *bc, int cpu,
return ret;
}
-int tick_resume_broadcast_oneshot(struct clock_event_device *bc)
+static void tick_resume_broadcast_oneshot(struct clock_event_device *bc)
{
- clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT);
- return 0;
+ clockevents_set_state(bc, CLOCK_EVT_STATE_ONESHOT);
}
/*
@@ -562,8 +566,8 @@ void tick_check_oneshot_broadcast_this_cpu(void)
* switched over, leave the device alone.
*/
if (td->mode == TICKDEV_MODE_ONESHOT) {
- clockevents_set_mode(td->evtdev,
- CLOCK_EVT_MODE_ONESHOT);
+ clockevents_set_state(td->evtdev,
+ CLOCK_EVT_STATE_ONESHOT);
}
}
}
@@ -666,31 +670,26 @@ static void broadcast_shutdown_local(struct clock_event_device *bc,
if (dev->next_event.tv64 < bc->next_event.tv64)
return;
}
- clockevents_set_mode(dev, CLOCK_EVT_MODE_SHUTDOWN);
+ clockevents_set_state(dev, CLOCK_EVT_STATE_SHUTDOWN);
}
-static void broadcast_move_bc(int deadcpu)
-{
- struct clock_event_device *bc = tick_broadcast_device.evtdev;
-
- if (!bc || !broadcast_needs_cpu(bc, deadcpu))
- return;
- /* This moves the broadcast assignment to this cpu */
- clockevents_program_event(bc, bc->next_event, 1);
-}
-
-/*
- * Powerstate information: The system enters/leaves a state, where
- * affected devices might stop
+/**
+ * tick_broadcast_oneshot_control - Enter/exit broadcast oneshot mode
+ * @state: The target state (enter/exit)
+ *
+ * The system enters/leaves a state, where affected devices might stop
* Returns 0 on success, -EBUSY if the cpu is used to broadcast wakeups.
+ *
+ * Called with interrupts disabled, so clockevents_lock is not
+ * required here because the local clock event device cannot go away
+ * under us.
*/
-int tick_broadcast_oneshot_control(unsigned long reason)
+int tick_broadcast_oneshot_control(enum tick_broadcast_state state)
{
struct clock_event_device *bc, *dev;
struct tick_device *td;
- unsigned long flags;
- ktime_t now;
int cpu, ret = 0;
+ ktime_t now;
/*
* Periodic mode does not care about the enter/exit of power
@@ -703,17 +702,17 @@ int tick_broadcast_oneshot_control(unsigned long reason)
* We are called with preemtion disabled from the depth of the
* idle code, so we can't be moved away.
*/
- cpu = smp_processor_id();
- td = &per_cpu(tick_cpu_device, cpu);
+ td = this_cpu_ptr(&tick_cpu_device);
dev = td->evtdev;
if (!(dev->features & CLOCK_EVT_FEAT_C3STOP))
return 0;
+ raw_spin_lock(&tick_broadcast_lock);
bc = tick_broadcast_device.evtdev;
+ cpu = smp_processor_id();
- raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
- if (reason == CLOCK_EVT_NOTIFY_BROADCAST_ENTER) {
+ if (state == TICK_BROADCAST_ENTER) {
if (!cpumask_test_and_set_cpu(cpu, tick_broadcast_oneshot_mask)) {
WARN_ON_ONCE(cpumask_test_cpu(cpu, tick_broadcast_pending_mask));
broadcast_shutdown_local(bc, dev);
@@ -741,7 +740,7 @@ int tick_broadcast_oneshot_control(unsigned long reason)
cpumask_clear_cpu(cpu, tick_broadcast_oneshot_mask);
} else {
if (cpumask_test_and_clear_cpu(cpu, tick_broadcast_oneshot_mask)) {
- clockevents_set_mode(dev, CLOCK_EVT_MODE_ONESHOT);
+ clockevents_set_state(dev, CLOCK_EVT_STATE_ONESHOT);
/*
* The cpu which was handling the broadcast
* timer marked this cpu in the broadcast
@@ -805,9 +804,10 @@ int tick_broadcast_oneshot_control(unsigned long reason)
}
}
out:
- raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
+ raw_spin_unlock(&tick_broadcast_lock);
return ret;
}
+EXPORT_SYMBOL_GPL(tick_broadcast_oneshot_control);
/*
* Reset the one shot broadcast for a cpu
@@ -842,7 +842,7 @@ void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
/* Set it up only once ! */
if (bc->event_handler != tick_handle_oneshot_broadcast) {
- int was_periodic = bc->mode == CLOCK_EVT_MODE_PERIODIC;
+ int was_periodic = bc->state == CLOCK_EVT_STATE_PERIODIC;
bc->event_handler = tick_handle_oneshot_broadcast;
@@ -858,7 +858,7 @@ void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
tick_broadcast_oneshot_mask, tmpmask);
if (was_periodic && !cpumask_empty(tmpmask)) {
- clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT);
+ clockevents_set_state(bc, CLOCK_EVT_STATE_ONESHOT);
tick_broadcast_init_next_event(tmpmask,
tick_next_period);
tick_broadcast_set_event(bc, cpu, tick_next_period, 1);
@@ -894,14 +894,28 @@ void tick_broadcast_switch_to_oneshot(void)
raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
}
+#ifdef CONFIG_HOTPLUG_CPU
+void hotplug_cpu__broadcast_tick_pull(int deadcpu)
+{
+ struct clock_event_device *bc;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
+ bc = tick_broadcast_device.evtdev;
+
+ if (bc && broadcast_needs_cpu(bc, deadcpu)) {
+ /* This moves the broadcast assignment to this CPU: */
+ clockevents_program_event(bc, bc->next_event, 1);
+ }
+ raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
+}
/*
* Remove a dead CPU from broadcasting
*/
-void tick_shutdown_broadcast_oneshot(unsigned int *cpup)
+void tick_shutdown_broadcast_oneshot(unsigned int cpu)
{
unsigned long flags;
- unsigned int cpu = *cpup;
raw_spin_lock_irqsave(&tick_broadcast_lock, flags);
@@ -913,10 +927,9 @@ void tick_shutdown_broadcast_oneshot(unsigned int *cpup)
cpumask_clear_cpu(cpu, tick_broadcast_pending_mask);
cpumask_clear_cpu(cpu, tick_broadcast_force_mask);
- broadcast_move_bc(cpu);
-
raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags);
}
+#endif
/*
* Check, whether the broadcast device is in one shot mode