diff --git a/arch/x86/xen/suspend.c b/arch/x86/xen/suspend.c index 033e428581f4..d9497698645a 100644 --- a/arch/x86/xen/suspend.c +++ b/arch/x86/xen/suspend.c @@ -85,7 +85,7 @@ static void xen_vcpu_notify_restore(void *data) if (smp_processor_id() == 0) return; - tick_resume(); + tick_resume_local(); } void xen_arch_resume(void) diff --git a/include/linux/tick.h b/include/linux/tick.h index 7e07e0e3d898..a3d4d2840e7f 100644 --- a/include/linux/tick.h +++ b/include/linux/tick.h @@ -29,13 +29,13 @@ extern struct tick_device *tick_get_device(int cpu); extern void __init tick_init(void); extern void tick_freeze(void); extern void tick_unfreeze(void); -/* Should be core only, but XEN resume magic abuses this interface */ -extern void tick_resume(void); +/* Should be core only, but XEN resume magic requires this */ +extern void tick_resume_local(void); #else /* CONFIG_GENERIC_CLOCKEVENTS */ static inline void tick_init(void) { } static inline void tick_freeze(void) { } static inline void tick_unfreeze(void) { } -static inline void tick_resume(void) { } +static inline void tick_resume_local(void) { } #endif /* !CONFIG_GENERIC_CLOCKEVENTS */ #ifdef CONFIG_TICK_ONESHOT diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 60e6c23ce1c7..19cfb381faa9 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -455,11 +455,26 @@ 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); @@ -472,8 +487,6 @@ int tick_resume_broadcast(void) 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)) @@ -482,11 +495,8 @@ int tick_resume_broadcast(void) } } raw_spin_unlock_irqrestore(&tick_broadcast_lock, flags); - - return broadcast; } - #ifdef CONFIG_TICK_ONESHOT static cpumask_var_t tick_broadcast_oneshot_mask; diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index 1a60c2ae96a8..da796d65d1fb 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -373,6 +373,41 @@ void tick_shutdown(unsigned int *cpup) } } +/** + * tick_suspend_local - Suspend the local tick device + * + * Called from the local cpu for freeze with interrupts disabled. + * + * No locks required. Nothing can change the per cpu device. + */ +static void tick_suspend_local(void) +{ + struct tick_device *td = this_cpu_ptr(&tick_cpu_device); + + clockevents_shutdown(td->evtdev); +} + +/** + * tick_resume_local - Resume the local tick device + * + * Called from the local CPU for unfreeze or XEN resume magic. + * + * No locks required. Nothing can change the per cpu device. + */ +void tick_resume_local(void) +{ + struct tick_device *td = this_cpu_ptr(&tick_cpu_device); + bool broadcast = tick_resume_check_broadcast(); + + clockevents_tick_resume(td->evtdev); + if (!broadcast) { + if (td->mode == TICKDEV_MODE_PERIODIC) + tick_setup_periodic(td->evtdev, 0); + else + tick_resume_oneshot(); + } +} + /** * tick_suspend - Suspend the tick and the broadcast device * @@ -384,9 +419,7 @@ void tick_shutdown(unsigned int *cpup) */ void tick_suspend(void) { - struct tick_device *td = this_cpu_ptr(&tick_cpu_device); - - clockevents_shutdown(td->evtdev); + tick_suspend_local(); tick_suspend_broadcast(); } @@ -394,26 +427,14 @@ void tick_suspend(void) * tick_resume - Resume the tick and the broadcast device * * Called from syscore_resume() via timekeeping_resume with only one - * CPU online and interrupts disabled or from tick_unfreeze() under - * tick_freeze_lock. + * CPU online and interrupts disabled. * * No locks required. Nothing can change the per cpu device. */ void tick_resume(void) { - struct tick_device *td; - int broadcast; - - broadcast = tick_resume_broadcast(); - td = this_cpu_ptr(&tick_cpu_device); - clockevents_tick_resume(td->evtdev); - - if (!broadcast) { - if (td->mode == TICKDEV_MODE_PERIODIC) - tick_setup_periodic(td->evtdev, 0); - else - tick_resume_oneshot(); - } + tick_resume_broadcast(); + tick_resume_local(); } static DEFINE_RAW_SPINLOCK(tick_freeze_lock); @@ -436,7 +457,7 @@ void tick_freeze(void) if (tick_freeze_depth == num_online_cpus()) { timekeeping_suspend(); } else { - tick_suspend(); + tick_suspend_local(); } raw_spin_unlock(&tick_freeze_lock); diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h index 5c9f0eec56b2..6ba7bce732f2 100644 --- a/kernel/time/tick-internal.h +++ b/kernel/time/tick-internal.h @@ -23,6 +23,7 @@ extern void tick_check_new_device(struct clock_event_device *dev); extern void tick_handover_do_timer(int *cpup); extern void tick_shutdown(unsigned int *cpup); extern void tick_suspend(void); +extern void tick_resume(void); extern bool tick_check_replacement(struct clock_event_device *curdev, struct clock_event_device *newdev); extern void tick_install_replacement(struct clock_event_device *dev); @@ -43,6 +44,7 @@ extern int __clockevents_update_freq(struct clock_event_device *dev, u32 freq); extern ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt); #else static inline void tick_suspend(void) { } +static inline void tick_resume(void) { } #endif /* GENERIC_CLOCKEVENTS */ /* Oneshot related functions */ @@ -81,7 +83,8 @@ 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_resume_broadcast(void); +extern bool tick_resume_check_broadcast(void); extern void tick_broadcast_init(void); extern void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast); extern int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq); @@ -95,7 +98,8 @@ 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; } +static inline void tick_resume_broadcast(void) { } +static inline bool tick_resume_check_broadcast(void) { return false; } static inline void tick_broadcast_init(void) { } static inline int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq) { return -ENODEV; }