xref: /openbmc/linux/include/linux/tick.h (revision 827634ad)
1 /*
2  * Tick related global functions
3  */
4 #ifndef _LINUX_TICK_H
5 #define _LINUX_TICK_H
6 
7 #include <linux/clockchips.h>
8 #include <linux/irqflags.h>
9 #include <linux/percpu.h>
10 #include <linux/context_tracking_state.h>
11 #include <linux/cpumask.h>
12 #include <linux/sched.h>
13 
14 #ifdef CONFIG_GENERIC_CLOCKEVENTS
15 extern void __init tick_init(void);
16 extern void tick_freeze(void);
17 extern void tick_unfreeze(void);
18 /* Should be core only, but ARM BL switcher requires it */
19 extern void tick_suspend_local(void);
20 /* Should be core only, but XEN resume magic and ARM BL switcher require it */
21 extern void tick_resume_local(void);
22 extern void tick_handover_do_timer(void);
23 extern void tick_cleanup_dead_cpu(int cpu);
24 #else /* CONFIG_GENERIC_CLOCKEVENTS */
25 static inline void tick_init(void) { }
26 static inline void tick_freeze(void) { }
27 static inline void tick_unfreeze(void) { }
28 static inline void tick_suspend_local(void) { }
29 static inline void tick_resume_local(void) { }
30 static inline void tick_handover_do_timer(void) { }
31 static inline void tick_cleanup_dead_cpu(int cpu) { }
32 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */
33 
34 #ifdef CONFIG_TICK_ONESHOT
35 extern void tick_irq_enter(void);
36 #  ifndef arch_needs_cpu
37 #   define arch_needs_cpu() (0)
38 #  endif
39 # else
40 static inline void tick_irq_enter(void) { }
41 #endif
42 
43 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
44 extern void hotplug_cpu__broadcast_tick_pull(int dead_cpu);
45 #else
46 static inline void hotplug_cpu__broadcast_tick_pull(int dead_cpu) { }
47 #endif
48 
49 enum tick_broadcast_mode {
50 	TICK_BROADCAST_OFF,
51 	TICK_BROADCAST_ON,
52 	TICK_BROADCAST_FORCE,
53 };
54 
55 enum tick_broadcast_state {
56 	TICK_BROADCAST_EXIT,
57 	TICK_BROADCAST_ENTER,
58 };
59 
60 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
61 extern void tick_broadcast_control(enum tick_broadcast_mode mode);
62 #else
63 static inline void tick_broadcast_control(enum tick_broadcast_mode mode) { }
64 #endif /* BROADCAST */
65 
66 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
67 extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state);
68 #else
69 static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state) { return 0; }
70 #endif
71 
72 static inline void tick_broadcast_enable(void)
73 {
74 	tick_broadcast_control(TICK_BROADCAST_ON);
75 }
76 static inline void tick_broadcast_disable(void)
77 {
78 	tick_broadcast_control(TICK_BROADCAST_OFF);
79 }
80 static inline void tick_broadcast_force(void)
81 {
82 	tick_broadcast_control(TICK_BROADCAST_FORCE);
83 }
84 static inline int tick_broadcast_enter(void)
85 {
86 	return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER);
87 }
88 static inline void tick_broadcast_exit(void)
89 {
90 	tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT);
91 }
92 
93 #ifdef CONFIG_NO_HZ_COMMON
94 extern int tick_nohz_tick_stopped(void);
95 extern void tick_nohz_idle_enter(void);
96 extern void tick_nohz_idle_exit(void);
97 extern void tick_nohz_irq_exit(void);
98 extern ktime_t tick_nohz_get_sleep_length(void);
99 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
100 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
101 #else /* !CONFIG_NO_HZ_COMMON */
102 static inline int tick_nohz_tick_stopped(void) { return 0; }
103 static inline void tick_nohz_idle_enter(void) { }
104 static inline void tick_nohz_idle_exit(void) { }
105 
106 static inline ktime_t tick_nohz_get_sleep_length(void)
107 {
108 	ktime_t len = { .tv64 = NSEC_PER_SEC/HZ };
109 
110 	return len;
111 }
112 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
113 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
114 #endif /* !CONFIG_NO_HZ_COMMON */
115 
116 #ifdef CONFIG_NO_HZ_FULL
117 extern bool tick_nohz_full_running;
118 extern cpumask_var_t tick_nohz_full_mask;
119 extern cpumask_var_t housekeeping_mask;
120 
121 static inline bool tick_nohz_full_enabled(void)
122 {
123 	if (!context_tracking_is_enabled())
124 		return false;
125 
126 	return tick_nohz_full_running;
127 }
128 
129 static inline bool tick_nohz_full_cpu(int cpu)
130 {
131 	if (!tick_nohz_full_enabled())
132 		return false;
133 
134 	return cpumask_test_cpu(cpu, tick_nohz_full_mask);
135 }
136 
137 extern void __tick_nohz_full_check(void);
138 extern void tick_nohz_full_kick(void);
139 extern void tick_nohz_full_kick_cpu(int cpu);
140 extern void tick_nohz_full_kick_all(void);
141 extern void __tick_nohz_task_switch(struct task_struct *tsk);
142 #else
143 static inline bool tick_nohz_full_enabled(void) { return false; }
144 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
145 static inline void __tick_nohz_full_check(void) { }
146 static inline void tick_nohz_full_kick_cpu(int cpu) { }
147 static inline void tick_nohz_full_kick(void) { }
148 static inline void tick_nohz_full_kick_all(void) { }
149 static inline void __tick_nohz_task_switch(struct task_struct *tsk) { }
150 #endif
151 
152 static inline bool is_housekeeping_cpu(int cpu)
153 {
154 #ifdef CONFIG_NO_HZ_FULL
155 	if (tick_nohz_full_enabled())
156 		return cpumask_test_cpu(cpu, housekeeping_mask);
157 #endif
158 	return true;
159 }
160 
161 static inline void housekeeping_affine(struct task_struct *t)
162 {
163 #ifdef CONFIG_NO_HZ_FULL
164 	if (tick_nohz_full_enabled())
165 		set_cpus_allowed_ptr(t, housekeeping_mask);
166 
167 #endif
168 }
169 
170 static inline void tick_nohz_full_check(void)
171 {
172 	if (tick_nohz_full_enabled())
173 		__tick_nohz_full_check();
174 }
175 
176 static inline void tick_nohz_task_switch(struct task_struct *tsk)
177 {
178 	if (tick_nohz_full_enabled())
179 		__tick_nohz_task_switch(tsk);
180 }
181 
182 #endif
183