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 11 #ifdef CONFIG_GENERIC_CLOCKEVENTS 12 13 enum tick_device_mode { 14 TICKDEV_MODE_PERIODIC, 15 TICKDEV_MODE_ONESHOT, 16 }; 17 18 struct tick_device { 19 struct clock_event_device *evtdev; 20 enum tick_device_mode mode; 21 }; 22 23 enum tick_nohz_mode { 24 NOHZ_MODE_INACTIVE, 25 NOHZ_MODE_LOWRES, 26 NOHZ_MODE_HIGHRES, 27 }; 28 29 /** 30 * struct tick_sched - sched tick emulation and no idle tick control/stats 31 * @sched_timer: hrtimer to schedule the periodic tick in high 32 * resolution mode 33 * @idle_tick: Store the last idle tick expiry time when the tick 34 * timer is modified for idle sleeps. This is necessary 35 * to resume the tick timer operation in the timeline 36 * when the CPU returns from idle 37 * @tick_stopped: Indicator that the idle tick has been stopped 38 * @idle_jiffies: jiffies at the entry to idle for idle time accounting 39 * @idle_calls: Total number of idle calls 40 * @idle_sleeps: Number of idle calls, where the sched tick was stopped 41 * @idle_entrytime: Time when the idle call was entered 42 * @idle_sleeptime: Sum of the time slept in idle with sched tick stopped 43 */ 44 struct tick_sched { 45 struct hrtimer sched_timer; 46 unsigned long check_clocks; 47 enum tick_nohz_mode nohz_mode; 48 ktime_t idle_tick; 49 int tick_stopped; 50 unsigned long idle_jiffies; 51 unsigned long idle_calls; 52 unsigned long idle_sleeps; 53 ktime_t idle_entrytime; 54 ktime_t idle_sleeptime; 55 unsigned long last_jiffies; 56 unsigned long next_jiffies; 57 ktime_t idle_expires; 58 }; 59 60 extern void __init tick_init(void); 61 extern int tick_is_oneshot_available(void); 62 extern struct tick_device *tick_get_device(int cpu); 63 64 # ifdef CONFIG_HIGH_RES_TIMERS 65 extern int tick_init_highres(void); 66 extern int tick_program_event(ktime_t expires, int force); 67 extern void tick_setup_sched_timer(void); 68 extern void tick_cancel_sched_timer(int cpu); 69 # else 70 static inline void tick_cancel_sched_timer(int cpu) { } 71 # endif /* HIGHRES */ 72 73 # ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST 74 extern struct tick_device *tick_get_broadcast_device(void); 75 extern cpumask_t *tick_get_broadcast_mask(void); 76 77 # ifdef CONFIG_TICK_ONESHOT 78 extern cpumask_t *tick_get_broadcast_oneshot_mask(void); 79 # endif 80 81 # endif /* BROADCAST */ 82 83 # ifdef CONFIG_TICK_ONESHOT 84 extern void tick_clock_notify(void); 85 extern int tick_check_oneshot_change(int allow_nohz); 86 extern struct tick_sched *tick_get_tick_sched(int cpu); 87 # else 88 static inline void tick_clock_notify(void) { } 89 static inline int tick_check_oneshot_change(int allow_nohz) { return 0; } 90 # endif 91 92 #else /* CONFIG_GENERIC_CLOCKEVENTS */ 93 static inline void tick_init(void) { } 94 static inline void tick_cancel_sched_timer(int cpu) { } 95 static inline void tick_clock_notify(void) { } 96 static inline int tick_check_oneshot_change(int allow_nohz) { return 0; } 97 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */ 98 99 # ifdef CONFIG_NO_HZ 100 extern void tick_nohz_stop_sched_tick(void); 101 extern void tick_nohz_restart_sched_tick(void); 102 extern void tick_nohz_update_jiffies(void); 103 # else 104 static inline void tick_nohz_stop_sched_tick(void) { } 105 static inline void tick_nohz_restart_sched_tick(void) { } 106 static inline void tick_nohz_update_jiffies(void) { } 107 # endif /* !NO_HZ */ 108 109 #endif 110