[PATCH] Save/restore periodic tick information over suspend/resume
The programming of periodic tick devices needs to be saved/restored
across suspend/resume - otherwise we might end up with a system coming
up that relies on getting a PIT (or HPET) interrupt, while those devices
default to 'no interrupts' after powerup. (To confuse things it worked
to a certain degree on some systems because the lapic gets initialized
as a side-effect of SMP bootup.)
This suspend / resume thing was dropped unintentionally during the
last-minute -mm code reshuffling.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 12b3efe..5567745 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -284,6 +284,42 @@
spin_unlock_irqrestore(&tick_broadcast_lock, flags);
}
+void tick_suspend_broadcast(void)
+{
+ struct clock_event_device *bc;
+ unsigned long flags;
+
+ spin_lock_irqsave(&tick_broadcast_lock, flags);
+
+ bc = tick_broadcast_device.evtdev;
+ if (bc && tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC)
+ clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN);
+
+ spin_unlock_irqrestore(&tick_broadcast_lock, flags);
+}
+
+int tick_resume_broadcast(void)
+{
+ struct clock_event_device *bc;
+ unsigned long flags;
+ int broadcast = 0;
+
+ spin_lock_irqsave(&tick_broadcast_lock, flags);
+
+ bc = tick_broadcast_device.evtdev;
+ if (bc) {
+ if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC &&
+ !cpus_empty(tick_broadcast_mask))
+ tick_broadcast_start_periodic(bc);
+
+ broadcast = cpu_isset(smp_processor_id(), tick_broadcast_mask);
+ }
+ spin_unlock_irqrestore(&tick_broadcast_lock, flags);
+
+ return broadcast;
+}
+
+
#ifdef CONFIG_TICK_ONESHOT
static cpumask_t tick_broadcast_oneshot_mask;