From 3494c16676a21e7e53e21b08a0a469a38df6dcfb Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Sat, 24 Feb 2007 22:11:42 -0800 Subject: [TICK] tick-common: Fix one-shot handling in tick_handle_periodic(). When clockevents_program_event() is given an expire time in the past, it does not update dev->next_event, so this looping code would loop forever once the first in-the-past expiration time was used. Keep advancing "next" locally to fix this bug. Acked-by: Thomas Gleixner Signed-off-by: David S. Miller --- kernel/time/tick-common.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'kernel/time/tick-common.c') diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index 4500e347f1bb..0986a2bfab49 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -77,6 +77,7 @@ static void tick_periodic(int cpu) void tick_handle_periodic(struct clock_event_device *dev) { int cpu = smp_processor_id(); + ktime_t next; tick_periodic(cpu); @@ -86,12 +87,12 @@ void tick_handle_periodic(struct clock_event_device *dev) * Setup the next period for devices, which do not have * periodic mode: */ + next = ktime_add(dev->next_event, tick_period); for (;;) { - ktime_t next = ktime_add(dev->next_event, tick_period); - if (!clockevents_program_event(dev, next, ktime_get())) return; tick_periodic(cpu); + next = ktime_add(next, tick_period); } } -- cgit v1.2.3 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(+) (limited to 'kernel/time/tick-common.c') 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 From cd05a1f818073a623455a58e756c5b419fc98db9 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sat, 17 Mar 2007 00:25:52 +0100 Subject: [PATCH] clockevents: Fix suspend/resume to disk hangs I finally found a dual core box, which survives suspend/resume without crashing in the middle of nowhere. Sigh, I never figured out from the code and the bug reports what's going on. The observed hangs are caused by a stale state transition of the clock event devices, which keeps the RCU synchronization away from completion, when the non boot CPU is brought back up. The suspend/resume in oneshot mode needs the similar care as the periodic mode during suspend to RAM. My assumption that the state transitions during the different shutdown/bringups of s2disk would go through the periodic boot phase and then switch over to highres resp. nohz mode were simply wrong. Add the appropriate suspend / resume handling for the non periodic modes. Signed-off-by: Thomas Gleixner Signed-off-by: Linus Torvalds --- kernel/time/tick-broadcast.c | 27 ++++++++++++++++++++++----- kernel/time/tick-common.c | 13 +++++++------ kernel/time/tick-internal.h | 11 ++++++++++- kernel/time/tick-oneshot.c | 12 ++++++++++++ 4 files changed, 51 insertions(+), 12 deletions(-) (limited to 'kernel/time/tick-common.c') diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 5567745470f7..eadfce2fff74 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -307,12 +307,19 @@ int tick_resume_broadcast(void) 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); + if (bc) { + switch (tick_broadcast_device.mode) { + case TICKDEV_MODE_PERIODIC: + if(!cpus_empty(tick_broadcast_mask)) + tick_broadcast_start_periodic(bc); + broadcast = cpu_isset(smp_processor_id(), + tick_broadcast_mask); + break; + case TICKDEV_MODE_ONESHOT: + broadcast = tick_resume_broadcast_oneshot(bc); + break; + } } spin_unlock_irqrestore(&tick_broadcast_lock, flags); @@ -347,6 +354,16 @@ static int tick_broadcast_set_event(ktime_t expires, int force) } } +int tick_resume_broadcast_oneshot(struct clock_event_device *bc) +{ + clockevents_set_mode(bc, CLOCK_EVT_MODE_ONESHOT); + + if(!cpus_empty(tick_broadcast_oneshot_mask)) + tick_broadcast_set_event(ktime_get(), 1); + + return cpu_isset(smp_processor_id(), tick_broadcast_oneshot_mask); +} + /* * Reprogram the broadcast device: * diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index 43ba1bdec14c..bfda3f7f0716 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -298,18 +298,17 @@ static void tick_shutdown(unsigned int *cpup) spin_unlock_irqrestore(&tick_device_lock, flags); } -static void tick_suspend_periodic(void) +static void tick_suspend(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); + clockevents_set_mode(td->evtdev, CLOCK_EVT_MODE_SHUTDOWN); spin_unlock_irqrestore(&tick_device_lock, flags); } -static void tick_resume_periodic(void) +static void tick_resume(void) { struct tick_device *td = &__get_cpu_var(tick_cpu_device); unsigned long flags; @@ -317,6 +316,8 @@ static void tick_resume_periodic(void) spin_lock_irqsave(&tick_device_lock, flags); if (td->mode == TICKDEV_MODE_PERIODIC) tick_setup_periodic(td->evtdev, 0); + else + tick_resume_oneshot(); spin_unlock_irqrestore(&tick_device_lock, flags); } @@ -348,13 +349,13 @@ static int tick_notify(struct notifier_block *nb, unsigned long reason, break; case CLOCK_EVT_NOTIFY_SUSPEND: - tick_suspend_periodic(); + tick_suspend(); tick_suspend_broadcast(); break; case CLOCK_EVT_NOTIFY_RESUME: if (!tick_resume_broadcast()) - tick_resume_periodic(); + tick_resume(); break; default: diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h index 75890efd24ff..c9d203bde518 100644 --- a/kernel/time/tick-internal.h +++ b/kernel/time/tick-internal.h @@ -19,12 +19,13 @@ extern void tick_setup_oneshot(struct clock_event_device *newdev, extern int tick_program_event(ktime_t expires, int force); extern void tick_oneshot_notify(void); extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *)); - +extern void tick_resume_oneshot(void); # ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST extern void tick_broadcast_setup_oneshot(struct clock_event_device *bc); extern void tick_broadcast_oneshot_control(unsigned long reason); extern void tick_broadcast_switch_to_oneshot(void); extern void tick_shutdown_broadcast_oneshot(unsigned int *cpup); +extern int tick_resume_broadcast_oneshot(struct clock_event_device *bc); # else /* BROADCAST */ static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc) { @@ -43,6 +44,10 @@ void tick_setup_oneshot(struct clock_event_device *newdev, { BUG(); } +static inline void tick_resume_oneshot(void) +{ + BUG(); +} static inline int tick_program_event(ktime_t expires, int force) { return 0; @@ -54,6 +59,10 @@ static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc) } static inline void tick_broadcast_oneshot_control(unsigned long reason) { } static inline void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { } +static inline int tick_resume_broadcast_oneshot(struct clock_event_device *bc) +{ + return 0; +} #endif /* !TICK_ONESHOT */ /* diff --git a/kernel/time/tick-oneshot.c b/kernel/time/tick-oneshot.c index 2e8b7ff863cc..f6997ab0c3c9 100644 --- a/kernel/time/tick-oneshot.c +++ b/kernel/time/tick-oneshot.c @@ -40,6 +40,18 @@ int tick_program_event(ktime_t expires, int force) } } +/** + * tick_resume_onshot - resume oneshot mode + */ +void tick_resume_oneshot(void) +{ + struct tick_device *td = &__get_cpu_var(tick_cpu_device); + struct clock_event_device *dev = td->evtdev; + + clockevents_set_mode(dev, CLOCK_EVT_MODE_ONESHOT); + tick_program_event(ktime_get(), 1); +} + /** * tick_setup_oneshot - setup the event device for oneshot mode (hres or nohz) */ -- cgit v1.2.3