1 /* linux/include/linux/tick.h
3 * This file contains the structure definitions for tick related functions
9 #include <linux/clockchips.h>
11 #ifdef CONFIG_GENERIC_CLOCKEVENTS
13 enum tick_device_mode
{
14 TICKDEV_MODE_PERIODIC
,
19 struct clock_event_device
*evtdev
;
20 enum tick_device_mode mode
;
30 * struct tick_sched - sched tick emulation and no idle tick control/stats
31 * @sched_timer: hrtimer to schedule the periodic tick in high
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_waketime: Time when the idle was interrupted
43 * @idle_exittime: Time when the idle state was left
44 * @idle_sleeptime: Sum of the time slept in idle with sched tick stopped
45 * @sleep_length: Duration of the current idle sleep
46 * @do_timer_lst: CPU was the last one doing do_timer before going idle
49 struct hrtimer sched_timer
;
50 unsigned long check_clocks
;
51 enum tick_nohz_mode nohz_mode
;
55 unsigned long idle_jiffies
;
56 unsigned long idle_calls
;
57 unsigned long idle_sleeps
;
59 ktime_t idle_entrytime
;
60 ktime_t idle_waketime
;
61 ktime_t idle_exittime
;
62 ktime_t idle_sleeptime
;
63 ktime_t idle_lastupdate
;
65 unsigned long last_jiffies
;
66 unsigned long next_jiffies
;
71 extern void __init
tick_init(void);
72 extern int tick_is_oneshot_available(void);
73 extern struct tick_device
*tick_get_device(int cpu
);
75 # ifdef CONFIG_HIGH_RES_TIMERS
76 extern int tick_init_highres(void);
77 extern int tick_program_event(ktime_t expires
, int force
);
78 extern void tick_setup_sched_timer(void);
81 # if defined CONFIG_NO_HZ || defined CONFIG_HIGH_RES_TIMERS
82 extern void tick_cancel_sched_timer(int cpu
);
84 static inline void tick_cancel_sched_timer(int cpu
) { }
87 # ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
88 extern struct tick_device
*tick_get_broadcast_device(void);
89 extern struct cpumask
*tick_get_broadcast_mask(void);
91 # ifdef CONFIG_TICK_ONESHOT
92 extern struct cpumask
*tick_get_broadcast_oneshot_mask(void);
95 # endif /* BROADCAST */
97 # ifdef CONFIG_TICK_ONESHOT
98 extern void tick_clock_notify(void);
99 extern int tick_check_oneshot_change(int allow_nohz
);
100 extern struct tick_sched
*tick_get_tick_sched(int cpu
);
101 extern void tick_check_idle(int cpu
);
102 extern int tick_oneshot_mode_active(void);
103 # ifndef arch_needs_cpu
104 # define arch_needs_cpu(cpu) (0)
107 static inline void tick_clock_notify(void) { }
108 static inline int tick_check_oneshot_change(int allow_nohz
) { return 0; }
109 static inline void tick_check_idle(int cpu
) { }
110 static inline int tick_oneshot_mode_active(void) { return 0; }
113 #else /* CONFIG_GENERIC_CLOCKEVENTS */
114 static inline void tick_init(void) { }
115 static inline void tick_cancel_sched_timer(int cpu
) { }
116 static inline void tick_clock_notify(void) { }
117 static inline int tick_check_oneshot_change(int allow_nohz
) { return 0; }
118 static inline void tick_check_idle(int cpu
) { }
119 static inline int tick_oneshot_mode_active(void) { return 0; }
120 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */
123 extern void tick_nohz_stop_sched_tick(int inidle
);
124 extern void tick_nohz_restart_sched_tick(void);
125 extern ktime_t
tick_nohz_get_sleep_length(void);
126 extern u64
get_cpu_idle_time_us(int cpu
, u64
*last_update_time
);
128 static inline void tick_nohz_stop_sched_tick(int inidle
) { }
129 static inline void tick_nohz_restart_sched_tick(void) { }
130 static inline ktime_t
tick_nohz_get_sleep_length(void)
132 ktime_t len
= { .tv64
= NSEC_PER_SEC
/HZ
};
136 static inline u64
get_cpu_idle_time_us(int cpu
, u64
*unused
) { return -1; }