xref: /linux/kernel/time/tick-internal.h (revision 2a2c74b2efcb1a0ca3fdcb5fbb96ad8de6a29177)
1 /*
2  * tick internal variable and functions used by low/high res code
3  */
4 #include <linux/hrtimer.h>
5 #include <linux/tick.h>
6 
7 extern seqlock_t jiffies_lock;
8 
9 #define CS_NAME_LEN	32
10 
11 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BUILD
12 
13 #define TICK_DO_TIMER_NONE	-1
14 #define TICK_DO_TIMER_BOOT	-2
15 
16 DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
17 extern ktime_t tick_next_period;
18 extern ktime_t tick_period;
19 extern int tick_do_timer_cpu __read_mostly;
20 
21 extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast);
22 extern void tick_handle_periodic(struct clock_event_device *dev);
23 extern void tick_check_new_device(struct clock_event_device *dev);
24 extern void tick_handover_do_timer(int *cpup);
25 extern void tick_shutdown(unsigned int *cpup);
26 extern void tick_suspend(void);
27 extern void tick_resume(void);
28 extern bool tick_check_replacement(struct clock_event_device *curdev,
29 				   struct clock_event_device *newdev);
30 extern void tick_install_replacement(struct clock_event_device *dev);
31 
32 extern void clockevents_shutdown(struct clock_event_device *dev);
33 
34 extern ssize_t sysfs_get_uname(const char *buf, char *dst, size_t cnt);
35 
36 /*
37  * NO_HZ / high resolution timer shared code
38  */
39 #ifdef CONFIG_TICK_ONESHOT
40 extern void tick_setup_oneshot(struct clock_event_device *newdev,
41 			       void (*handler)(struct clock_event_device *),
42 			       ktime_t nextevt);
43 extern int tick_program_event(ktime_t expires, int force);
44 extern void tick_oneshot_notify(void);
45 extern int tick_switch_to_oneshot(void (*handler)(struct clock_event_device *));
46 extern void tick_resume_oneshot(void);
47 # ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
48 extern void tick_broadcast_setup_oneshot(struct clock_event_device *bc);
49 extern int tick_broadcast_oneshot_control(unsigned long reason);
50 extern void tick_broadcast_switch_to_oneshot(void);
51 extern void tick_shutdown_broadcast_oneshot(unsigned int *cpup);
52 extern int tick_resume_broadcast_oneshot(struct clock_event_device *bc);
53 extern int tick_broadcast_oneshot_active(void);
54 extern void tick_check_oneshot_broadcast_this_cpu(void);
55 bool tick_broadcast_oneshot_available(void);
56 # else /* BROADCAST */
57 static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
58 {
59 	BUG();
60 }
61 static inline int tick_broadcast_oneshot_control(unsigned long reason) { return 0; }
62 static inline void tick_broadcast_switch_to_oneshot(void) { }
63 static inline void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { }
64 static inline int tick_broadcast_oneshot_active(void) { return 0; }
65 static inline void tick_check_oneshot_broadcast_this_cpu(void) { }
66 static inline bool tick_broadcast_oneshot_available(void) { return true; }
67 # endif /* !BROADCAST */
68 
69 #else /* !ONESHOT */
70 static inline
71 void tick_setup_oneshot(struct clock_event_device *newdev,
72 			void (*handler)(struct clock_event_device *),
73 			ktime_t nextevt)
74 {
75 	BUG();
76 }
77 static inline void tick_resume_oneshot(void)
78 {
79 	BUG();
80 }
81 static inline int tick_program_event(ktime_t expires, int force)
82 {
83 	return 0;
84 }
85 static inline void tick_oneshot_notify(void) { }
86 static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
87 {
88 	BUG();
89 }
90 static inline int tick_broadcast_oneshot_control(unsigned long reason) { return 0; }
91 static inline void tick_shutdown_broadcast_oneshot(unsigned int *cpup) { }
92 static inline int tick_resume_broadcast_oneshot(struct clock_event_device *bc)
93 {
94 	return 0;
95 }
96 static inline int tick_broadcast_oneshot_active(void) { return 0; }
97 static inline bool tick_broadcast_oneshot_available(void) { return false; }
98 #endif /* !TICK_ONESHOT */
99 
100 /*
101  * Broadcasting support
102  */
103 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
104 extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu);
105 extern void tick_install_broadcast_device(struct clock_event_device *dev);
106 extern int tick_is_broadcast_device(struct clock_event_device *dev);
107 extern void tick_broadcast_on_off(unsigned long reason, int *oncpu);
108 extern void tick_shutdown_broadcast(unsigned int *cpup);
109 extern void tick_suspend_broadcast(void);
110 extern int tick_resume_broadcast(void);
111 extern void tick_broadcast_init(void);
112 extern void
113 tick_set_periodic_handler(struct clock_event_device *dev, int broadcast);
114 int tick_broadcast_update_freq(struct clock_event_device *dev, u32 freq);
115 
116 #else /* !BROADCAST */
117 
118 static inline void tick_install_broadcast_device(struct clock_event_device *dev)
119 {
120 }
121 
122 static inline int tick_is_broadcast_device(struct clock_event_device *dev)
123 {
124 	return 0;
125 }
126 static inline int tick_device_uses_broadcast(struct clock_event_device *dev,
127 					     int cpu)
128 {
129 	return 0;
130 }
131 static inline void tick_do_periodic_broadcast(struct clock_event_device *d) { }
132 static inline void tick_broadcast_on_off(unsigned long reason, int *oncpu) { }
133 static inline void tick_shutdown_broadcast(unsigned int *cpup) { }
134 static inline void tick_suspend_broadcast(void) { }
135 static inline int tick_resume_broadcast(void) { return 0; }
136 static inline void tick_broadcast_init(void) { }
137 static inline int tick_broadcast_update_freq(struct clock_event_device *dev,
138 					     u32 freq) { return -ENODEV; }
139 
140 /*
141  * Set the periodic handler in non broadcast mode
142  */
143 static inline void tick_set_periodic_handler(struct clock_event_device *dev,
144 					     int broadcast)
145 {
146 	dev->event_handler = tick_handle_periodic;
147 }
148 #endif /* !BROADCAST */
149 
150 /*
151  * Check, if the device is functional or a dummy for broadcast
152  */
153 static inline int tick_device_is_functional(struct clock_event_device *dev)
154 {
155 	return !(dev->features & CLOCK_EVT_FEAT_DUMMY);
156 }
157 
158 int __clockevents_update_freq(struct clock_event_device *dev, u32 freq);
159 
160 #endif
161 
162 extern void do_timer(unsigned long ticks);
163 extern void update_wall_time(void);
164