From 6321dd60c76b2e12383bc06046288b15397ed3a0 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Tue, 6 Mar 2007 08:25:42 +0100 Subject: [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 Signed-off-by: Ingo Molnar Signed-off-by: Linus Torvalds --- kernel/time/tick-broadcast.c | 36 ++++++++++++++++++++++++++++++++++++ kernel/time/tick-common.c | 32 ++++++++++++++++++++++++++++++++ kernel/time/tick-internal.h | 4 ++++ kernel/timer.c | 6 ++++++ 4 files changed, 78 insertions(+) diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 12b3efeb9f6f..5567745470f7 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -284,6 +284,42 @@ void tick_shutdown_broadcast(unsigned int *cpup) 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; diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index 0986a2bfab49..43ba1bdec14c 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -298,6 +298,28 @@ static void tick_shutdown(unsigned int *cpup) spin_unlock_irqrestore(&tick_device_lock, flags); } +static void tick_suspend_periodic(void) +{ + struct tick_device *td = &__get_cpu_var(tick_cpu_device); + unsigned long flags; + + spin_lock_irqsave(&tick_device_lock, flags); + if (td->mode == TICKDEV_MODE_PERIODIC) + clockevents_set_mode(td->evtdev, CLOCK_EVT_MODE_SHUTDOWN); + spin_unlock_irqrestore(&tick_device_lock, flags); +} + +static void tick_resume_periodic(void) +{ + struct tick_device *td = &__get_cpu_var(tick_cpu_device); + unsigned long flags; + + spin_lock_irqsave(&tick_device_lock, flags); + if (td->mode == TICKDEV_MODE_PERIODIC) + tick_setup_periodic(td->evtdev, 0); + spin_unlock_irqrestore(&tick_device_lock, flags); +} + /* * Notification about clock event devices */ @@ -325,6 +347,16 @@ static int tick_notify(struct notifier_block *nb, unsigned long reason, tick_shutdown(dev); break; + case CLOCK_EVT_NOTIFY_SUSPEND: + tick_suspend_periodic(); + tick_suspend_broadcast(); + break; + + case CLOCK_EVT_NOTIFY_RESUME: + if (!tick_resume_broadcast()) + tick_resume_periodic(); + break; + default: break; } diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h index 54861a0f29ff..75890efd24ff 100644 --- a/kernel/time/tick-internal.h +++ b/kernel/time/tick-internal.h @@ -67,6 +67,8 @@ extern int tick_check_broadcast_device(struct clock_event_device *dev); extern int tick_is_broadcast_device(struct clock_event_device *dev); extern void tick_broadcast_on_off(unsigned long reason, int *oncpu); extern void tick_shutdown_broadcast(unsigned int *cpup); +extern void tick_suspend_broadcast(void); +extern int tick_resume_broadcast(void); extern void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast); @@ -90,6 +92,8 @@ static inline int tick_device_uses_broadcast(struct clock_event_device *dev, static inline void tick_do_periodic_broadcast(struct clock_event_device *d) { } static inline void tick_broadcast_on_off(unsigned long reason, int *oncpu) { } static inline void tick_shutdown_broadcast(unsigned int *cpup) { } +static inline void tick_suspend_broadcast(void) { } +static inline int tick_resume_broadcast(void) { return 0; } /* * Set the periodic handler in non broadcast mode diff --git a/kernel/timer.c b/kernel/timer.c index 8ad384253ef2..ee0a2da4aab3 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -997,6 +997,9 @@ static int timekeeping_resume(struct sys_device *dev) write_sequnlock_irqrestore(&xtime_lock, flags); touch_softlockup_watchdog(); + + clockevents_notify(CLOCK_EVT_NOTIFY_RESUME, NULL); + /* Resume hrtimers */ clock_was_set(); @@ -1011,6 +1014,9 @@ static int timekeeping_suspend(struct sys_device *dev, pm_message_t state) timekeeping_suspended = 1; timekeeping_suspend_time = read_persistent_clock(); write_sequnlock_irqrestore(&xtime_lock, flags); + + clockevents_notify(CLOCK_EVT_NOTIFY_SUSPEND, NULL); + return 0; } -- cgit v1.2.3