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
15extern void __init tick_init(void);
16extern void tick_freeze(void);
17extern void tick_unfreeze(void);
18/* Should be core only, but ARM BL switcher requires it */
19extern void tick_suspend_local(void);
20/* Should be core only, but XEN resume magic and ARM BL switcher require it */
21extern void tick_resume_local(void);
22extern void tick_handover_do_timer(void);
23extern void tick_cleanup_dead_cpu(int cpu);
24#else /* CONFIG_GENERIC_CLOCKEVENTS */
25static inline void tick_init(void) { }
26static inline void tick_freeze(void) { }
27static inline void tick_unfreeze(void) { }
28static inline void tick_suspend_local(void) { }
29static inline void tick_resume_local(void) { }
30static inline void tick_handover_do_timer(void) { }
31static inline void tick_cleanup_dead_cpu(int cpu) { }
32#endif /* !CONFIG_GENERIC_CLOCKEVENTS */
33
34#ifdef CONFIG_TICK_ONESHOT
35extern void tick_irq_enter(void);
36#  ifndef arch_needs_cpu
37#   define arch_needs_cpu() (0)
38#  endif
39# else
40static inline void tick_irq_enter(void) { }
41#endif
42
43#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
44extern void hotplug_cpu__broadcast_tick_pull(int dead_cpu);
45#else
46static inline void hotplug_cpu__broadcast_tick_pull(int dead_cpu) { }
47#endif
48
49enum tick_broadcast_mode {
50	TICK_BROADCAST_OFF,
51	TICK_BROADCAST_ON,
52	TICK_BROADCAST_FORCE,
53};
54
55enum tick_broadcast_state {
56	TICK_BROADCAST_EXIT,
57	TICK_BROADCAST_ENTER,
58};
59
60#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
61extern void tick_broadcast_control(enum tick_broadcast_mode mode);
62#else
63static 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)
67extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state);
68#else
69static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state) { return 0; }
70#endif
71
72static inline void tick_broadcast_enable(void)
73{
74	tick_broadcast_control(TICK_BROADCAST_ON);
75}
76static inline void tick_broadcast_disable(void)
77{
78	tick_broadcast_control(TICK_BROADCAST_OFF);
79}
80static inline void tick_broadcast_force(void)
81{
82	tick_broadcast_control(TICK_BROADCAST_FORCE);
83}
84static inline int tick_broadcast_enter(void)
85{
86	return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER);
87}
88static inline void tick_broadcast_exit(void)
89{
90	tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT);
91}
92
93#ifdef CONFIG_NO_HZ_COMMON
94extern int tick_nohz_tick_stopped(void);
95extern void tick_nohz_idle_enter(void);
96extern void tick_nohz_idle_exit(void);
97extern void tick_nohz_irq_exit(void);
98extern ktime_t tick_nohz_get_sleep_length(void);
99extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
100extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
101#else /* !CONFIG_NO_HZ_COMMON */
102static inline int tick_nohz_tick_stopped(void) { return 0; }
103static inline void tick_nohz_idle_enter(void) { }
104static inline void tick_nohz_idle_exit(void) { }
105
106static inline ktime_t tick_nohz_get_sleep_length(void)
107{
108	ktime_t len = { .tv64 = NSEC_PER_SEC/HZ };
109
110	return len;
111}
112static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
113static 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
117extern bool tick_nohz_full_running;
118extern cpumask_var_t tick_nohz_full_mask;
119extern cpumask_var_t housekeeping_mask;
120
121static 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
129static 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
137extern void __tick_nohz_full_check(void);
138extern void tick_nohz_full_kick(void);
139extern void tick_nohz_full_kick_cpu(int cpu);
140extern void tick_nohz_full_kick_all(void);
141extern void __tick_nohz_task_switch(struct task_struct *tsk);
142#else
143static inline bool tick_nohz_full_enabled(void) { return false; }
144static inline bool tick_nohz_full_cpu(int cpu) { return false; }
145static inline void __tick_nohz_full_check(void) { }
146static inline void tick_nohz_full_kick_cpu(int cpu) { }
147static inline void tick_nohz_full_kick(void) { }
148static inline void tick_nohz_full_kick_all(void) { }
149static inline void __tick_nohz_task_switch(struct task_struct *tsk) { }
150#endif
151
152static 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
161static 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
170static inline void tick_nohz_full_check(void)
171{
172	if (tick_nohz_full_enabled())
173		__tick_nohz_full_check();
174}
175
176static 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