1/* linux/include/linux/tick.h 2 * 3 * This file contains the structure definitions for tick related functions 4 * 5 */ 6#ifndef _LINUX_TICK_H 7#define _LINUX_TICK_H 8 9#include <linux/clockchips.h> 10#include <linux/irqflags.h> 11 12#ifdef CONFIG_GENERIC_CLOCKEVENTS 13 14enum tick_device_mode { 15 TICKDEV_MODE_PERIODIC, 16 TICKDEV_MODE_ONESHOT, 17}; 18 19struct tick_device { 20 struct clock_event_device *evtdev; 21 enum tick_device_mode mode; 22}; 23 24enum tick_nohz_mode { 25 NOHZ_MODE_INACTIVE, 26 NOHZ_MODE_LOWRES, 27 NOHZ_MODE_HIGHRES, 28}; 29 30/** 31 * struct tick_sched - sched tick emulation and no idle tick control/stats 32 * @sched_timer: hrtimer to schedule the periodic tick in high 33 * resolution mode 34 * @idle_tick: Store the last idle tick expiry time when the tick 35 * timer is modified for idle sleeps. This is necessary 36 * to resume the tick timer operation in the timeline 37 * when the CPU returns from idle 38 * @tick_stopped: Indicator that the idle tick has been stopped 39 * @idle_jiffies: jiffies at the entry to idle for idle time accounting 40 * @idle_calls: Total number of idle calls 41 * @idle_sleeps: Number of idle calls, where the sched tick was stopped 42 * @idle_entrytime: Time when the idle call was entered 43 * @idle_waketime: Time when the idle was interrupted 44 * @idle_exittime: Time when the idle state was left 45 * @idle_sleeptime: Sum of the time slept in idle with sched tick stopped 46 * @iowait_sleeptime: Sum of the time slept in idle with sched tick stopped, with IO outstanding 47 * @sleep_length: Duration of the current idle sleep 48 * @do_timer_lst: CPU was the last one doing do_timer before going idle 49 */ 50struct tick_sched { 51 struct hrtimer sched_timer; 52 unsigned long check_clocks; 53 enum tick_nohz_mode nohz_mode; 54 ktime_t idle_tick; 55 int inidle; 56 int tick_stopped; 57 unsigned long idle_jiffies; 58 unsigned long idle_calls; 59 unsigned long idle_sleeps; 60 int idle_active; 61 ktime_t idle_entrytime; 62 ktime_t idle_waketime; 63 ktime_t idle_exittime; 64 ktime_t idle_sleeptime; 65 ktime_t iowait_sleeptime; 66 ktime_t sleep_length; 67 unsigned long last_jiffies; 68 unsigned long next_jiffies; 69 ktime_t idle_expires; 70 int do_timer_last; 71}; 72 73extern void __init tick_init(void); 74extern int tick_is_oneshot_available(void); 75extern struct tick_device *tick_get_device(int cpu); 76 77# ifdef CONFIG_HIGH_RES_TIMERS 78extern int tick_init_highres(void); 79extern int tick_program_event(ktime_t expires, int force); 80extern void tick_setup_sched_timer(void); 81# endif 82 83# if defined CONFIG_NO_HZ || defined CONFIG_HIGH_RES_TIMERS 84extern void tick_cancel_sched_timer(int cpu); 85# else 86static inline void tick_cancel_sched_timer(int cpu) { } 87# endif 88 89# ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST 90extern struct tick_device *tick_get_broadcast_device(void); 91extern struct cpumask *tick_get_broadcast_mask(void); 92 93# ifdef CONFIG_TICK_ONESHOT 94extern struct cpumask *tick_get_broadcast_oneshot_mask(void); 95# endif 96 97# endif /* BROADCAST */ 98 99# ifdef CONFIG_TICK_ONESHOT 100extern void tick_clock_notify(void); 101extern int tick_check_oneshot_change(int allow_nohz); 102extern struct tick_sched *tick_get_tick_sched(int cpu); 103extern void tick_check_idle(int cpu); 104extern int tick_oneshot_mode_active(void); 105# ifndef arch_needs_cpu 106# define arch_needs_cpu(cpu) (0) 107# endif 108# else 109static inline void tick_clock_notify(void) { } 110static inline int tick_check_oneshot_change(int allow_nohz) { return 0; } 111static inline void tick_check_idle(int cpu) { } 112static inline int tick_oneshot_mode_active(void) { return 0; } 113# endif 114 115#else /* CONFIG_GENERIC_CLOCKEVENTS */ 116static inline void tick_init(void) { } 117static inline void tick_cancel_sched_timer(int cpu) { } 118static inline void tick_clock_notify(void) { } 119static inline int tick_check_oneshot_change(int allow_nohz) { return 0; } 120static inline void tick_check_idle(int cpu) { } 121static inline int tick_oneshot_mode_active(void) { return 0; } 122#endif /* !CONFIG_GENERIC_CLOCKEVENTS */ 123 124# ifdef CONFIG_NO_HZ 125extern void tick_nohz_idle_enter(void); 126extern void tick_nohz_idle_exit(void); 127extern void tick_nohz_irq_exit(void); 128extern ktime_t tick_nohz_get_sleep_length(void); 129extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time); 130extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time); 131# else 132static inline void tick_nohz_idle_enter(void) { } 133static inline void tick_nohz_idle_exit(void) { } 134 135static inline ktime_t tick_nohz_get_sleep_length(void) 136{ 137 ktime_t len = { .tv64 = NSEC_PER_SEC/HZ }; 138 139 return len; 140} 141static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; } 142static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; } 143# endif /* !NO_HZ */ 144 145#endif 146