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 14 enum tick_device_mode { 15 TICKDEV_MODE_PERIODIC, 16 TICKDEV_MODE_ONESHOT, 17 }; 18 19 struct tick_device { 20 struct clock_event_device *evtdev; 21 enum tick_device_mode mode; 22 }; 23 24 enum 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 */ 50 struct 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 73 extern void __init tick_init(void); 74 extern int tick_is_oneshot_available(void); 75 extern struct tick_device *tick_get_device(int cpu); 76 77 # ifdef CONFIG_HIGH_RES_TIMERS 78 extern int tick_init_highres(void); 79 extern int tick_program_event(ktime_t expires, int force); 80 extern void tick_setup_sched_timer(void); 81 # endif 82 83 # if defined CONFIG_NO_HZ || defined CONFIG_HIGH_RES_TIMERS 84 extern void tick_cancel_sched_timer(int cpu); 85 # else tick_cancel_sched_timer(int cpu)86 static inline void tick_cancel_sched_timer(int cpu) { } 87 # endif 88 89 # ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST 90 extern struct tick_device *tick_get_broadcast_device(void); 91 extern struct cpumask *tick_get_broadcast_mask(void); 92 93 # ifdef CONFIG_TICK_ONESHOT 94 extern struct cpumask *tick_get_broadcast_oneshot_mask(void); 95 # endif 96 97 # endif /* BROADCAST */ 98 99 # ifdef CONFIG_TICK_ONESHOT 100 extern void tick_clock_notify(void); 101 extern int tick_check_oneshot_change(int allow_nohz); 102 extern struct tick_sched *tick_get_tick_sched(int cpu); 103 extern void tick_check_idle(int cpu); 104 extern int tick_oneshot_mode_active(void); 105 # ifndef arch_needs_cpu 106 # define arch_needs_cpu(cpu) (0) 107 # endif 108 # else tick_clock_notify(void)109 static inline void tick_clock_notify(void) { } tick_check_oneshot_change(int allow_nohz)110 static inline int tick_check_oneshot_change(int allow_nohz) { return 0; } tick_check_idle(int cpu)111 static inline void tick_check_idle(int cpu) { } tick_oneshot_mode_active(void)112 static inline int tick_oneshot_mode_active(void) { return 0; } 113 # endif 114 115 #else /* CONFIG_GENERIC_CLOCKEVENTS */ tick_init(void)116 static inline void tick_init(void) { } tick_cancel_sched_timer(int cpu)117 static inline void tick_cancel_sched_timer(int cpu) { } tick_clock_notify(void)118 static inline void tick_clock_notify(void) { } tick_check_oneshot_change(int allow_nohz)119 static inline int tick_check_oneshot_change(int allow_nohz) { return 0; } tick_check_idle(int cpu)120 static inline void tick_check_idle(int cpu) { } tick_oneshot_mode_active(void)121 static inline int tick_oneshot_mode_active(void) { return 0; } 122 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */ 123 124 # ifdef CONFIG_NO_HZ 125 extern void tick_nohz_idle_enter(void); 126 extern void tick_nohz_idle_exit(void); 127 extern void tick_nohz_irq_exit(void); 128 extern ktime_t tick_nohz_get_sleep_length(void); 129 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time); 130 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time); 131 # else tick_nohz_idle_enter(void)132 static inline void tick_nohz_idle_enter(void) { } tick_nohz_idle_exit(void)133 static inline void tick_nohz_idle_exit(void) { } 134 tick_nohz_get_sleep_length(void)135 static inline ktime_t tick_nohz_get_sleep_length(void) 136 { 137 ktime_t len = { .tv64 = NSEC_PER_SEC/HZ }; 138 139 return len; 140 } get_cpu_idle_time_us(int cpu,u64 * unused)141 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; } get_cpu_iowait_time_us(int cpu,u64 * unused)142 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; } 143 # endif /* !NO_HZ */ 144 145 #endif 146