LXR linux/kernel/time/tick-internal.h

   1/*
   2 * tick internal variable and functions used by low/high res code
   3 */
   4#include <linux/hrtimer.h>
   5#include <linux/tick.h>
   6
   7#include "timekeeping.h"
   8#include "tick-sched.h"
   9
  10#ifdef CONFIG_GENERIC_CLOCKEVENTS
  11
  12# define TICK_DO_TIMER_NONE     -1
  13# define TICK_DO_TIMER_BOOT     -2
  14
  15DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
  16extern ktime_t tick_next_period;
  17extern ktime_t tick_period;
  18extern int tick_do_timer_cpu __read_mostly;
  19
  20extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast);
  21extern void tick_handle_periodic(struct clock_event_device *dev);
  22extern void tick_check_new_device(struct clock_event_device *dev);
  23extern void tick_shutdown(unsigned int cpu);
  24extern void tick_suspend(void);
  25extern void tick_resume(void);
  26extern bool tick_check_replacement(struct clock_event_device *curdev,
  27                                   struct clock_event_device *newdev);
  28extern void tick_install_replacement(struct clock_event_device *dev);
  29extern int tick_is_oneshot_available(void);
  30extern struct tick_device *tick_get_device(int cpu);
  31
  32extern int clockevents_tick_resume(struct clock_event_device *dev);
  33/* Check, if the device is functional or a dummy for broadcast */
  34static inline int tick_device_is_functional(struct clock_event_device *dev)
  35{
  36        return !(dev->features & CLOCK_EVT_FEAT_DUMMY);
  37}
  38
  39static inline enum clock_event_state clockevent_get_state(struct clock_event_device *dev)
  40{
  41        return dev->state_use_accessors;
  42}
  43
  44static inline void clockevent_set_state(struct clock_event_device *dev,
  45                                        enum clock_event_state state)
  46{
  47        dev->state_use_accessors = state;
  48}
  49
  50extern void clockevents_shutdown(struct clock_event_device *dev);
  51extern void clockevents_exchange_device(struct clock_event_device *old,
  52                                        struct clock_event_device *new);
  53extern void clockevents_switch_state(struct clock_event_device *dev,
  54                                     enum clock_event_state state);
  55extern int clockevents_program_event(struct clock_event_device *dev,
  56                                     ktime_t expires, bool force);
  57extern void clockevents_handle_noop(struct clock_event_device *dev);
  58extern int __clockevents_update_freq(struct clock_event_device *dev, u32 freq);
  59extern ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt);
  60
  61/* Broadcasting support */
  62# ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
  63extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu);
  64extern void tick_install_broadcast_device(struct clock_event_device *dev);
  65extern int tick_is_broadcast_device(struct clock_event_device *dev);
  66extern void tick_shutdown_broadcast(unsigned int cpu);
  67extern void tick_suspend_broadcast(void);
  68extern void tick_resume_broadcast(void);
  69extern bool tick_resume_check_broadcast(void);
  70extern void tick_broadcast_init(void);
  71extern void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast);
  72extern int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq);
  73extern struct tick_device *tick_get_broadcast_device(void);
  74extern struct cpumask *tick_get_broadcast_mask(void);
  75# else /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST: */
  76static inline void tick_install_broadcast_device(struct clock_event_device *dev) { }
  77static inline int tick_is_broadcast_device(struct clock_event_device *dev) { return 0; }
  78static inline int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu) { return 0; }
  79static inline void tick_do_periodic_broadcast(struct clock_event_device *d) { }
  80static inline void tick_shutdown_broadcast(unsigned int cpu) { }
  81static inline void tick_suspend_broadcast(void) { }
  82static inline void tick_resume_broadcast(void) { }
  83static inline bool tick_resume_check_broadcast(void) { return false; }
  84static inline void tick_broadcast_init(void) { }
  85static inline int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq) { return -ENODEV; }
  86
  87/* Set the periodic handler in non broadcast mode */
  88static inline void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast)
  89{
  90        dev->event_handler = tick_handle_periodic;
  91}
  92# endif /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST */
  93
  94#else /* !GENERIC_CLOCKEVENTS: */
  95static inline void tick_suspend(void) { }
  96static inline void tick_resume(void) { }
  97#endif /* !GENERIC_CLOCKEVENTS */
  98
  99/* Oneshot related functions */
 100#ifdef CONFIG_TICK_ONESHOT
 101extern void tick_setup_oneshot(struct clock_event_device *newdev,
 102                               void (*handler)(struct clock_event_device *),
 103                               ktime_t nextevt);
 104extern int tick_program_event(ktime_t expires, int force);
 105extern void tick_oneshot_notify(void);
 106extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *));
 107extern void tick_resume_oneshot(void);
 108static inline bool tick_oneshot_possible(void) { return true; }
 109extern int tick_oneshot_mode_active(void);
 110extern void tick_clock_notify(void);
 111extern int tick_check_oneshot_change(int allow_nohz);
 112extern int tick_init_highres(void);
 113#else /* !CONFIG_TICK_ONESHOT: */
 114static inline
 115void tick_setup_oneshot(struct clock_event_device *newdev,
 116                        void (*handler)(struct clock_event_device *),
 117                        ktime_t nextevt) { BUG(); }
 118static inline void tick_resume_oneshot(void) { BUG(); }
 119static inline int tick_program_event(ktime_t expires, int force) { return 0; }
 120static inline void tick_oneshot_notify(void) { }
 121static inline bool tick_oneshot_possible(void) { return false; }
 122static inline int tick_oneshot_mode_active(void) { return 0; }
 123static inline void tick_clock_notify(void) { }
 124static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
 125#endif /* !CONFIG_TICK_ONESHOT */
 126
 127/* Functions related to oneshot broadcasting */
 128#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
 129extern void tick_broadcast_switch_to_oneshot(void);
 130extern void tick_shutdown_broadcast_oneshot(unsigned int cpu);
 131extern int tick_broadcast_oneshot_active(void);
 132extern void tick_check_oneshot_broadcast_this_cpu(void);
 133bool tick_broadcast_oneshot_available(void);
 134extern struct cpumask *tick_get_broadcast_oneshot_mask(void);
 135#else /* !(BROADCAST && ONESHOT): */
 136static inline void tick_broadcast_switch_to_oneshot(void) { }
 137static inline void tick_shutdown_broadcast_oneshot(unsigned int cpu) { }
 138static inline int tick_broadcast_oneshot_active(void) { return 0; }
 139static inline void tick_check_oneshot_broadcast_this_cpu(void) { }
 140static inline bool tick_broadcast_oneshot_available(void) { return tick_oneshot_possible(); }
 141#endif /* !(BROADCAST && ONESHOT) */
 142
 143/* NO_HZ_FULL internal */
 144#ifdef CONFIG_NO_HZ_FULL
 145extern void tick_nohz_init(void);
 146# else
 147static inline void tick_nohz_init(void) { }
 148#endif
 149
 150#ifdef CONFIG_NO_HZ_COMMON
 151extern unsigned long tick_nohz_active;
 152#else
 153#define tick_nohz_active (0)
 154#endif
 155
 156#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
 157extern void timers_update_migration(bool update_nohz);
 158#else
 159static inline void timers_update_migration(bool update_nohz) { }
 160#endif
 161
 162DECLARE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases);
 163
 164extern u64 get_next_timer_interrupt(unsigned long basej, u64 basem);
 165void timer_clear_idle(void);
 166