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 ktime_t tick_period; 19 extern int tick_do_timer_cpu __read_mostly; 20 21 extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast); 22 extern void tick_handle_periodic(struct clock_event_device *dev); 23 extern void tick_check_new_device(struct clock_event_device *dev); 24 extern void tick_shutdown(unsigned int cpu); 25 extern void tick_suspend(void); 26 extern void tick_resume(void); 27 extern bool tick_check_replacement(struct clock_event_device *curdev, 28 struct clock_event_device *newdev); 29 extern void tick_install_replacement(struct clock_event_device *dev); 30 extern int tick_is_oneshot_available(void); 31 extern struct tick_device *tick_get_device(int cpu); 32 33 extern int clockevents_tick_resume(struct clock_event_device *dev); 34 /* Check, if the device is functional or a dummy for broadcast */ 35 static inline int tick_device_is_functional(struct clock_event_device *dev) 36 { 37 return !(dev->features & CLOCK_EVT_FEAT_DUMMY); 38 } 39 40 static inline enum clock_event_state clockevent_get_state(struct clock_event_device *dev) 41 { 42 return dev->state_use_accessors; 43 } 44 45 static inline void clockevent_set_state(struct clock_event_device *dev, 46 enum clock_event_state state) 47 { 48 dev->state_use_accessors = state; 49 } 50 51 extern void clockevents_shutdown(struct clock_event_device *dev); 52 extern void clockevents_exchange_device(struct clock_event_device *old, 53 struct clock_event_device *new); 54 extern void clockevents_switch_state(struct clock_event_device *dev, 55 enum clock_event_state state); 56 extern int clockevents_program_event(struct clock_event_device *dev, 57 ktime_t expires, bool force); 58 extern void clockevents_handle_noop(struct clock_event_device *dev); 59 extern int __clockevents_update_freq(struct clock_event_device *dev, u32 freq); 60 extern ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt); 61 62 /* Broadcasting support */ 63 # ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST 64 extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu); 65 extern void tick_install_broadcast_device(struct clock_event_device *dev); 66 extern int tick_is_broadcast_device(struct clock_event_device *dev); 67 extern void tick_suspend_broadcast(void); 68 extern void tick_resume_broadcast(void); 69 extern bool tick_resume_check_broadcast(void); 70 extern void tick_broadcast_init(void); 71 extern void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast); 72 extern int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq); 73 extern struct tick_device *tick_get_broadcast_device(void); 74 extern struct cpumask *tick_get_broadcast_mask(void); 75 # else /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST: */ 76 static inline void tick_install_broadcast_device(struct clock_event_device *dev) { } 77 static inline int tick_is_broadcast_device(struct clock_event_device *dev) { return 0; } 78 static inline int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu) { return 0; } 79 static inline void tick_do_periodic_broadcast(struct clock_event_device *d) { } 80 static inline void tick_suspend_broadcast(void) { } 81 static inline void tick_resume_broadcast(void) { } 82 static inline bool tick_resume_check_broadcast(void) { return false; } 83 static inline void tick_broadcast_init(void) { } 84 static inline int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq) { return -ENODEV; } 85 86 /* Set the periodic handler in non broadcast mode */ 87 static inline void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast) 88 { 89 dev->event_handler = tick_handle_periodic; 90 } 91 # endif /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST */ 92 93 #else /* !GENERIC_CLOCKEVENTS: */ 94 static inline void tick_suspend(void) { } 95 static inline void tick_resume(void) { } 96 #endif /* !GENERIC_CLOCKEVENTS */ 97 98 /* Oneshot related functions */ 99 #ifdef CONFIG_TICK_ONESHOT 100 extern void tick_setup_oneshot(struct clock_event_device *newdev, 101 void (*handler)(struct clock_event_device *), 102 ktime_t nextevt); 103 extern int tick_program_event(ktime_t expires, int force); 104 extern void tick_oneshot_notify(void); 105 extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *)); 106 extern void tick_resume_oneshot(void); 107 static inline bool tick_oneshot_possible(void) { return true; } 108 extern int tick_oneshot_mode_active(void); 109 extern void tick_clock_notify(void); 110 extern int tick_check_oneshot_change(int allow_nohz); 111 extern int tick_init_highres(void); 112 #else /* !CONFIG_TICK_ONESHOT: */ 113 static inline 114 void tick_setup_oneshot(struct clock_event_device *newdev, 115 void (*handler)(struct clock_event_device *), 116 ktime_t nextevt) { BUG(); } 117 static inline void tick_resume_oneshot(void) { BUG(); } 118 static inline int tick_program_event(ktime_t expires, int force) { return 0; } 119 static inline void tick_oneshot_notify(void) { } 120 static inline bool tick_oneshot_possible(void) { return false; } 121 static inline int tick_oneshot_mode_active(void) { return 0; } 122 static inline void tick_clock_notify(void) { } 123 static inline int tick_check_oneshot_change(int allow_nohz) { return 0; } 124 #endif /* !CONFIG_TICK_ONESHOT */ 125 126 /* Functions related to oneshot broadcasting */ 127 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT) 128 extern void tick_broadcast_switch_to_oneshot(void); 129 extern int tick_broadcast_oneshot_active(void); 130 extern void tick_check_oneshot_broadcast_this_cpu(void); 131 bool tick_broadcast_oneshot_available(void); 132 extern struct cpumask *tick_get_broadcast_oneshot_mask(void); 133 #else /* !(BROADCAST && ONESHOT): */ 134 static inline void tick_broadcast_switch_to_oneshot(void) { } 135 static inline int tick_broadcast_oneshot_active(void) { return 0; } 136 static inline void tick_check_oneshot_broadcast_this_cpu(void) { } 137 static inline bool tick_broadcast_oneshot_available(void) { return tick_oneshot_possible(); } 138 #endif /* !(BROADCAST && ONESHOT) */ 139 140 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_HOTPLUG_CPU) 141 extern void tick_broadcast_offline(unsigned int cpu); 142 #else 143 static inline void tick_broadcast_offline(unsigned int cpu) { } 144 #endif 145 146 /* NO_HZ_FULL internal */ 147 #ifdef CONFIG_NO_HZ_FULL 148 extern void tick_nohz_init(void); 149 # else 150 static inline void tick_nohz_init(void) { } 151 #endif 152 153 #ifdef CONFIG_NO_HZ_COMMON 154 extern unsigned long tick_nohz_active; 155 extern void timers_update_nohz(void); 156 # ifdef CONFIG_SMP 157 extern struct static_key_false timers_migration_enabled; 158 # endif 159 #else /* CONFIG_NO_HZ_COMMON */ 160 static inline void timers_update_nohz(void) { } 161 #define tick_nohz_active (0) 162 #endif 163 164 DECLARE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases); 165 166 extern u64 get_next_timer_interrupt(unsigned long basej, u64 basem); 167 void timer_clear_idle(void); 168