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 #include <linux/percpu.h>
12 #include <linux/hrtimer.h>
13
14 #ifdef CONFIG_GENERIC_CLOCKEVENTS
15
16 enum tick_device_mode {
17 TICKDEV_MODE_PERIODIC,
18 TICKDEV_MODE_ONESHOT,
19 };
20
21 struct tick_device {
22 struct clock_event_device *evtdev;
23 enum tick_device_mode mode;
24 };
25
26 enum tick_nohz_mode {
27 NOHZ_MODE_INACTIVE,
28 NOHZ_MODE_LOWRES,
29 NOHZ_MODE_HIGHRES,
30 };
31
32 /**
33 * struct tick_sched - sched tick emulation and no idle tick control/stats
34 * @sched_timer: hrtimer to schedule the periodic tick in high
35 * resolution mode
36 * @last_tick: Store the last tick expiry time when the tick
37 * timer is modified for nohz sleeps. This is necessary
38 * to resume the tick timer operation in the timeline
39 * when the CPU returns from nohz sleep.
40 * @tick_stopped: Indicator that the idle tick has been stopped
41 * @idle_jiffies: jiffies at the entry to idle for idle time accounting
42 * @idle_calls: Total number of idle calls
43 * @idle_sleeps: Number of idle calls, where the sched tick was stopped
44 * @idle_entrytime: Time when the idle call was entered
45 * @idle_waketime: Time when the idle was interrupted
46 * @idle_exittime: Time when the idle state was left
47 * @idle_sleeptime: Sum of the time slept in idle with sched tick stopped
48 * @iowait_sleeptime: Sum of the time slept in idle with sched tick stopped, with IO outstanding
49 * @sleep_length: Duration of the current idle sleep
50 * @do_timer_lst: CPU was the last one doing do_timer before going idle
51 */
52 struct tick_sched {
53 struct hrtimer sched_timer;
54 unsigned long check_clocks;
55 enum tick_nohz_mode nohz_mode;
56 ktime_t last_tick;
57 int inidle;
58 int tick_stopped;
59 unsigned long idle_jiffies;
60 unsigned long idle_calls;
61 unsigned long idle_sleeps;
62 int idle_active;
63 ktime_t idle_entrytime;
64 ktime_t idle_waketime;
65 ktime_t idle_exittime;
66 ktime_t idle_sleeptime;
67 ktime_t iowait_sleeptime;
68 ktime_t sleep_length;
69 unsigned long last_jiffies;
70 unsigned long next_jiffies;
71 ktime_t idle_expires;
72 int do_timer_last;
73 };
74
75 extern void __init tick_init(void);
76 extern int tick_is_oneshot_available(void);
77 extern struct tick_device *tick_get_device(int cpu);
78
79 # ifdef CONFIG_HIGH_RES_TIMERS
80 extern int tick_init_highres(void);
81 extern int tick_program_event(ktime_t expires, int force);
82 extern void tick_setup_sched_timer(void);
83 # endif
84
85 # if defined CONFIG_NO_HZ_COMMON || defined CONFIG_HIGH_RES_TIMERS
86 extern void tick_cancel_sched_timer(int cpu);
87 # else
tick_cancel_sched_timer(int cpu)88 static inline void tick_cancel_sched_timer(int cpu) { }
89 # endif
90
91 # ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
92 extern struct tick_device *tick_get_broadcast_device(void);
93 extern struct cpumask *tick_get_broadcast_mask(void);
94
95 # ifdef CONFIG_TICK_ONESHOT
96 extern struct cpumask *tick_get_broadcast_oneshot_mask(void);
97 # endif
98
99 # endif /* BROADCAST */
100
101 # ifdef CONFIG_TICK_ONESHOT
102 extern void tick_clock_notify(void);
103 extern int tick_check_oneshot_change(int allow_nohz);
104 extern struct tick_sched *tick_get_tick_sched(int cpu);
105 extern void tick_check_idle(int cpu);
106 extern int tick_oneshot_mode_active(void);
107 # ifndef arch_needs_cpu
108 # define arch_needs_cpu(cpu) (0)
109 # endif
110 # else
tick_clock_notify(void)111 static inline void tick_clock_notify(void) { }
tick_check_oneshot_change(int allow_nohz)112 static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
tick_check_idle(int cpu)113 static inline void tick_check_idle(int cpu) { }
tick_oneshot_mode_active(void)114 static inline int tick_oneshot_mode_active(void) { return 0; }
115 # endif
116
117 #else /* CONFIG_GENERIC_CLOCKEVENTS */
tick_init(void)118 static inline void tick_init(void) { }
tick_cancel_sched_timer(int cpu)119 static inline void tick_cancel_sched_timer(int cpu) { }
tick_clock_notify(void)120 static inline void tick_clock_notify(void) { }
tick_check_oneshot_change(int allow_nohz)121 static inline int tick_check_oneshot_change(int allow_nohz) { return 0; }
tick_check_idle(int cpu)122 static inline void tick_check_idle(int cpu) { }
tick_oneshot_mode_active(void)123 static inline int tick_oneshot_mode_active(void) { return 0; }
124 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */
125
126 # ifdef CONFIG_NO_HZ_COMMON
127 DECLARE_PER_CPU(struct tick_sched, tick_cpu_sched);
128
tick_nohz_tick_stopped(void)129 static inline int tick_nohz_tick_stopped(void)
130 {
131 return __this_cpu_read(tick_cpu_sched.tick_stopped);
132 }
133
134 extern void tick_nohz_idle_enter(void);
135 extern void tick_nohz_idle_exit(void);
136 extern void tick_nohz_irq_exit(void);
137 extern ktime_t tick_nohz_get_sleep_length(void);
138 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
139 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
140
141 # else /* !CONFIG_NO_HZ_COMMON */
tick_nohz_tick_stopped(void)142 static inline int tick_nohz_tick_stopped(void)
143 {
144 return 0;
145 }
146
tick_nohz_idle_enter(void)147 static inline void tick_nohz_idle_enter(void) { }
tick_nohz_idle_exit(void)148 static inline void tick_nohz_idle_exit(void) { }
149
tick_nohz_get_sleep_length(void)150 static inline ktime_t tick_nohz_get_sleep_length(void)
151 {
152 ktime_t len = { .tv64 = NSEC_PER_SEC/HZ };
153
154 return len;
155 }
get_cpu_idle_time_us(int cpu,u64 * unused)156 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
get_cpu_iowait_time_us(int cpu,u64 * unused)157 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
158 # endif /* !CONFIG_NO_HZ_COMMON */
159
160 #ifdef CONFIG_NO_HZ_FULL
161 extern void tick_nohz_init(void);
162 extern int tick_nohz_full_cpu(int cpu);
163 extern void tick_nohz_full_check(void);
164 extern void tick_nohz_full_kick(void);
165 extern void tick_nohz_full_kick_all(void);
166 extern void tick_nohz_task_switch(struct task_struct *tsk);
167 #else
tick_nohz_init(void)168 static inline void tick_nohz_init(void) { }
tick_nohz_full_cpu(int cpu)169 static inline int tick_nohz_full_cpu(int cpu) { return 0; }
tick_nohz_full_check(void)170 static inline void tick_nohz_full_check(void) { }
tick_nohz_full_kick(void)171 static inline void tick_nohz_full_kick(void) { }
tick_nohz_full_kick_all(void)172 static inline void tick_nohz_full_kick_all(void) { }
tick_nohz_task_switch(struct task_struct * tsk)173 static inline void tick_nohz_task_switch(struct task_struct *tsk) { }
174 #endif
175
176
177 # ifdef CONFIG_CPU_IDLE_GOV_MENU
178 extern void menu_hrtimer_cancel(void);
179 # else
menu_hrtimer_cancel(void)180 static inline void menu_hrtimer_cancel(void) {}
181 # endif /* CONFIG_CPU_IDLE_GOV_MENU */
182
183 #endif
184