kernel/time/tick-internal.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * tick internal variable and functions used by low/high res code
   4  */
   5 #include <linux/hrtimer.h>
   6 #include <linux/tick.h>
   7
   8 #include "timekeeping.h"
   9 #include "tick-sched.h"
  10
  11 #ifdef CONFIG_GENERIC_CLOCKEVENTS
  12
  13 # define TICK_DO_TIMER_NONE     -1
  14 # define TICK_DO_TIMER_BOOT     -2
  15
  16 DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
  17 extern ktime_t tick_next_period;
  18 extern int tick_do_timer_cpu __read_mostly;
  19
  20 extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast);
  21 extern void tick_handle_periodic(struct clock_event_device *dev);
  22 extern void tick_check_new_device(struct clock_event_device *dev);
  23 extern void tick_shutdown(unsigned int cpu);
  24 extern void tick_suspend(void);
  25 extern void tick_resume(void);
  26 extern bool tick_check_replacement(struct clock_event_device *curdev,
  27                                    struct clock_event_device *newdev);
  28 extern void tick_install_replacement(struct clock_event_device *dev);
  29 extern int tick_is_oneshot_available(void);
  30 extern struct tick_device *tick_get_device(int cpu);
  31
  32 extern int clockevents_tick_resume(struct clock_event_device *dev);
  33 /* Check, if the device is functional or a dummy for broadcast */
  34 static inline int tick_device_is_functional(struct clock_event_device *dev)
  35 {
  36         return !(dev->features & CLOCK_EVT_FEAT_DUMMY);
  37 }
  38
  39 static inline enum clock_event_state clockevent_get_state(struct clock_event_device *dev)
  40 {
  41         return dev->state_use_accessors;
  42 }
  43
  44 static 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
  50 extern void clockevents_shutdown(struct clock_event_device *dev);
  51 extern void clockevents_exchange_device(struct clock_event_device *old,
  52                                         struct clock_event_device *new);
  53 extern void clockevents_switch_state(struct clock_event_device *dev,
  54                                      enum clock_event_state state);
  55 extern int clockevents_program_event(struct clock_event_device *dev,
  56                                      ktime_t expires, bool force);
  57 extern void clockevents_handle_noop(struct clock_event_device *dev);
  58 extern int __clockevents_update_freq(struct clock_event_device *dev, u32 freq);
  59 extern ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt);
  60
  61 /* Broadcasting support */
  62 # ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
  63 extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu);
  64 extern void tick_install_broadcast_device(struct clock_event_device *dev);
  65 extern int tick_is_broadcast_device(struct clock_event_device *dev);
  66 extern void tick_suspend_broadcast(void);
  67 extern void tick_resume_broadcast(void);
  68 extern bool tick_resume_check_broadcast(void);
  69 extern void tick_broadcast_init(void);
  70 extern void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast);
  71 extern int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq);
  72 extern struct tick_device *tick_get_broadcast_device(void);
  73 extern struct cpumask *tick_get_broadcast_mask(void);
  74 # else /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST: */
  75 static inline void tick_install_broadcast_device(struct clock_event_device *dev) { }
  76 static inline int tick_is_broadcast_device(struct clock_event_device *dev) { return 0; }
  77 static inline int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu) { return 0; }
  78 static inline void tick_do_periodic_broadcast(struct clock_event_device *d) { }
  79 static inline void tick_suspend_broadcast(void) { }
  80 static inline void tick_resume_broadcast(void) { }
  81 static inline bool tick_resume_check_broadcast(void) { return false; }
  82 static inline void tick_broadcast_init(void) { }
  83 static inline int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq) { return -ENODEV; }
  84
  85 /* Set the periodic handler in non broadcast mode */
  86 static inline void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast)
  87 {
  88         dev->event_handler = tick_handle_periodic;
  89 }
  90 # endif /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST */
  91
  92 #else /* !GENERIC_CLOCKEVENTS: */
  93 static inline void tick_suspend(void) { }
  94 static inline void tick_resume(void) { }
  95 #endif /* !GENERIC_CLOCKEVENTS */
  96
  97 /* Oneshot related functions */
  98 #ifdef CONFIG_TICK_ONESHOT
  99 extern void tick_setup_oneshot(struct clock_event_device *newdev,
 100                                void (*handler)(struct clock_event_device *),
 101                                ktime_t nextevt);
 102 extern int tick_program_event(ktime_t expires, int force);
 103 extern void tick_oneshot_notify(void);
 104 extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *));
 105 extern void tick_resume_oneshot(void);
 106 static inline bool tick_oneshot_possible(void) { return true; }
 107 extern int tick_oneshot_mode_active(void);
 108 extern void tick_clock_notify(void);
 109 extern int tick_check_oneshot_change(int allow_nohz);
 110 extern int tick_init_highres(void);
 111 #else /* !CONFIG_TICK_ONESHOT: */
 112 static inline
 113 void tick_setup_oneshot(struct clock_event_device *newdev,
 114                         void (*handler)(struct clock_event_device *),
 115                         ktime_t nextevt) { BUG(); }
 116 static inline void tick_resume_oneshot(void) { BUG(); }
 117 static inline int tick_program_event(ktime_t expires, int force) { return 0; }
 118 static inline void tick_oneshot_notify(void) { }
 119 static inline bool tick_oneshot_possible(void) { return false; }
 120 static inline int tick_oneshot_mode_active(void) { return 0; }
 121 static inline void tick_clock_notify(void) { }
 122 static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
 123 #endif /* !CONFIG_TICK_ONESHOT */
 124
 125 /* Functions related to oneshot broadcasting */
 126 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
 127 extern void tick_broadcast_switch_to_oneshot(void);
 128 extern int tick_broadcast_oneshot_active(void);
 129 extern void tick_check_oneshot_broadcast_this_cpu(void);
 130 bool tick_broadcast_oneshot_available(void);
 131 extern struct cpumask *tick_get_broadcast_oneshot_mask(void);
 132 #else /* !(BROADCAST && ONESHOT): */
 133 static inline void tick_broadcast_switch_to_oneshot(void) { }
 134 static inline int tick_broadcast_oneshot_active(void) { return 0; }
 135 static inline void tick_check_oneshot_broadcast_this_cpu(void) { }
 136 static inline bool tick_broadcast_oneshot_available(void) { return tick_oneshot_possible(); }
 137 #endif /* !(BROADCAST && ONESHOT) */
 138
 139 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_HOTPLUG_CPU)
 140 extern void tick_broadcast_offline(unsigned int cpu);
 141 #else
 142 static inline void tick_broadcast_offline(unsigned int cpu) { }
 143 #endif
 144
 145 /* NO_HZ_FULL internal */
 146 #ifdef CONFIG_NO_HZ_FULL
 147 extern void tick_nohz_init(void);
 148 # else
 149 static inline void tick_nohz_init(void) { }
 150 #endif
 151
 152 #ifdef CONFIG_NO_HZ_COMMON
 153 extern unsigned long tick_nohz_active;
 154 extern void timers_update_nohz(void);
 155 # ifdef CONFIG_SMP
 156 extern struct static_key_false timers_migration_enabled;
 157 # endif
 158 #else /* CONFIG_NO_HZ_COMMON */
 159 static inline void timers_update_nohz(void) { }
 160 #define tick_nohz_active (0)
 161 #endif
 162
 163 DECLARE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases);
 164
 165 extern u64 get_next_timer_interrupt(unsigned long basej, u64 basem);
 166 void timer_clear_idle(void);