tick-internal.h (8056B)
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 16DECLARE_PER_CPU(struct tick_device, tick_cpu_device); 17extern ktime_t tick_next_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, int cpu); 65extern int tick_is_broadcast_device(struct clock_event_device *dev); 66extern void tick_suspend_broadcast(void); 67extern void tick_resume_broadcast(void); 68extern bool tick_resume_check_broadcast(void); 69extern void tick_broadcast_init(void); 70extern void tick_set_periodic_handler(struct clock_event_device *dev, int broadcast); 71extern int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq); 72extern struct tick_device *tick_get_broadcast_device(void); 73extern struct cpumask *tick_get_broadcast_mask(void); 74extern const struct clock_event_device *tick_get_wakeup_device(int cpu); 75# else /* !CONFIG_GENERIC_CLOCKEVENTS_BROADCAST: */ 76static inline void tick_install_broadcast_device(struct clock_event_device *dev, int cpu) { } 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_suspend_broadcast(void) { } 81static inline void tick_resume_broadcast(void) { } 82static inline bool tick_resume_check_broadcast(void) { return false; } 83static inline void tick_broadcast_init(void) { } 84static 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 */ 87static 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: */ 94static inline void tick_suspend(void) { } 95static inline void tick_resume(void) { } 96#endif /* !GENERIC_CLOCKEVENTS */ 97 98/* Oneshot related functions */ 99#ifdef CONFIG_TICK_ONESHOT 100extern void tick_setup_oneshot(struct clock_event_device *newdev, 101 void (*handler)(struct clock_event_device *), 102 ktime_t nextevt); 103extern int tick_program_event(ktime_t expires, int force); 104extern void tick_oneshot_notify(void); 105extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *)); 106extern void tick_resume_oneshot(void); 107static inline bool tick_oneshot_possible(void) { return true; } 108extern int tick_oneshot_mode_active(void); 109extern void tick_clock_notify(void); 110extern int tick_check_oneshot_change(int allow_nohz); 111extern int tick_init_highres(void); 112#else /* !CONFIG_TICK_ONESHOT: */ 113static inline 114void tick_setup_oneshot(struct clock_event_device *newdev, 115 void (*handler)(struct clock_event_device *), 116 ktime_t nextevt) { BUG(); } 117static inline void tick_resume_oneshot(void) { BUG(); } 118static inline int tick_program_event(ktime_t expires, int force) { return 0; } 119static inline void tick_oneshot_notify(void) { } 120static inline bool tick_oneshot_possible(void) { return false; } 121static inline int tick_oneshot_mode_active(void) { return 0; } 122static inline void tick_clock_notify(void) { } 123static 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) 128extern void tick_broadcast_switch_to_oneshot(void); 129extern int tick_broadcast_oneshot_active(void); 130extern void tick_check_oneshot_broadcast_this_cpu(void); 131bool tick_broadcast_oneshot_available(void); 132extern struct cpumask *tick_get_broadcast_oneshot_mask(void); 133#else /* !(BROADCAST && ONESHOT): */ 134static inline void tick_broadcast_switch_to_oneshot(void) { } 135static inline int tick_broadcast_oneshot_active(void) { return 0; } 136static inline void tick_check_oneshot_broadcast_this_cpu(void) { } 137static 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) 141extern void tick_broadcast_offline(unsigned int cpu); 142#else 143static inline void tick_broadcast_offline(unsigned int cpu) { } 144#endif 145 146/* NO_HZ_FULL internal */ 147#ifdef CONFIG_NO_HZ_FULL 148extern void tick_nohz_init(void); 149# else 150static inline void tick_nohz_init(void) { } 151#endif 152 153#ifdef CONFIG_NO_HZ_COMMON 154extern unsigned long tick_nohz_active; 155extern void timers_update_nohz(void); 156# ifdef CONFIG_SMP 157extern struct static_key_false timers_migration_enabled; 158# endif 159#else /* CONFIG_NO_HZ_COMMON */ 160static inline void timers_update_nohz(void) { } 161#define tick_nohz_active (0) 162#endif 163 164DECLARE_PER_CPU(struct hrtimer_cpu_base, hrtimer_bases); 165 166extern u64 get_next_timer_interrupt(unsigned long basej, u64 basem); 167void timer_clear_idle(void); 168 169#define CLOCK_SET_WALL \ 170 (BIT(HRTIMER_BASE_REALTIME) | BIT(HRTIMER_BASE_REALTIME_SOFT) | \ 171 BIT(HRTIMER_BASE_TAI) | BIT(HRTIMER_BASE_TAI_SOFT)) 172 173#define CLOCK_SET_BOOT \ 174 (BIT(HRTIMER_BASE_BOOTTIME) | BIT(HRTIMER_BASE_BOOTTIME_SOFT)) 175 176void clock_was_set(unsigned int bases); 177void clock_was_set_delayed(void); 178 179void hrtimers_resume_local(void); 180 181/* Since jiffies uses a simple TICK_NSEC multiplier 182 * conversion, the .shift value could be zero. However 183 * this would make NTP adjustments impossible as they are 184 * in units of 1/2^.shift. Thus we use JIFFIES_SHIFT to 185 * shift both the nominator and denominator the same 186 * amount, and give ntp adjustments in units of 1/2^8 187 * 188 * The value 8 is somewhat carefully chosen, as anything 189 * larger can result in overflows. TICK_NSEC grows as HZ 190 * shrinks, so values greater than 8 overflow 32bits when 191 * HZ=100. 192 */ 193#if HZ < 34 194#define JIFFIES_SHIFT 6 195#elif HZ < 67 196#define JIFFIES_SHIFT 7 197#else 198#define JIFFIES_SHIFT 8 199#endif