Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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);
16/* Should be core only, but ARM BL switcher requires it */
17extern void tick_suspend_local(void);
18/* Should be core only, but XEN resume magic and ARM BL switcher require it */
19extern void tick_resume_local(void);
20extern void tick_handover_do_timer(void);
21extern void tick_cleanup_dead_cpu(int cpu);
22#else /* CONFIG_GENERIC_CLOCKEVENTS */
23static inline void tick_init(void) { }
24static inline void tick_suspend_local(void) { }
25static inline void tick_resume_local(void) { }
26static inline void tick_handover_do_timer(void) { }
27static inline void tick_cleanup_dead_cpu(int cpu) { }
28#endif /* !CONFIG_GENERIC_CLOCKEVENTS */
29
30#if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_SUSPEND)
31extern void tick_freeze(void);
32extern void tick_unfreeze(void);
33#else
34static inline void tick_freeze(void) { }
35static inline void tick_unfreeze(void) { }
36#endif
37
38#ifdef CONFIG_TICK_ONESHOT
39extern void tick_irq_enter(void);
40# ifndef arch_needs_cpu
41# define arch_needs_cpu() (0)
42# endif
43# else
44static inline void tick_irq_enter(void) { }
45#endif
46
47#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
48extern void hotplug_cpu__broadcast_tick_pull(int dead_cpu);
49#else
50static inline void hotplug_cpu__broadcast_tick_pull(int dead_cpu) { }
51#endif
52
53enum tick_broadcast_mode {
54 TICK_BROADCAST_OFF,
55 TICK_BROADCAST_ON,
56 TICK_BROADCAST_FORCE,
57};
58
59enum tick_broadcast_state {
60 TICK_BROADCAST_EXIT,
61 TICK_BROADCAST_ENTER,
62};
63
64#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
65extern void tick_broadcast_control(enum tick_broadcast_mode mode);
66#else
67static inline void tick_broadcast_control(enum tick_broadcast_mode mode) { }
68#endif /* BROADCAST */
69
70#ifdef CONFIG_GENERIC_CLOCKEVENTS
71extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state);
72#else
73static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state)
74{
75 return 0;
76}
77#endif
78
79static inline void tick_broadcast_enable(void)
80{
81 tick_broadcast_control(TICK_BROADCAST_ON);
82}
83static inline void tick_broadcast_disable(void)
84{
85 tick_broadcast_control(TICK_BROADCAST_OFF);
86}
87static inline void tick_broadcast_force(void)
88{
89 tick_broadcast_control(TICK_BROADCAST_FORCE);
90}
91static inline int tick_broadcast_enter(void)
92{
93 return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER);
94}
95static inline void tick_broadcast_exit(void)
96{
97 tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT);
98}
99
100#ifdef CONFIG_NO_HZ_COMMON
101extern int tick_nohz_enabled;
102extern int tick_nohz_tick_stopped(void);
103extern void tick_nohz_idle_enter(void);
104extern void tick_nohz_idle_exit(void);
105extern void tick_nohz_irq_exit(void);
106extern ktime_t tick_nohz_get_sleep_length(void);
107extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
108extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
109#else /* !CONFIG_NO_HZ_COMMON */
110#define tick_nohz_enabled (0)
111static inline int tick_nohz_tick_stopped(void) { return 0; }
112static inline void tick_nohz_idle_enter(void) { }
113static inline void tick_nohz_idle_exit(void) { }
114
115static inline ktime_t tick_nohz_get_sleep_length(void)
116{
117 ktime_t len = { .tv64 = NSEC_PER_SEC/HZ };
118
119 return len;
120}
121static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
122static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
123#endif /* !CONFIG_NO_HZ_COMMON */
124
125#ifdef CONFIG_NO_HZ_FULL
126extern bool tick_nohz_full_running;
127extern cpumask_var_t tick_nohz_full_mask;
128extern cpumask_var_t housekeeping_mask;
129
130static inline bool tick_nohz_full_enabled(void)
131{
132 if (!context_tracking_is_enabled())
133 return false;
134
135 return tick_nohz_full_running;
136}
137
138static inline bool tick_nohz_full_cpu(int cpu)
139{
140 if (!tick_nohz_full_enabled())
141 return false;
142
143 return cpumask_test_cpu(cpu, tick_nohz_full_mask);
144}
145
146static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
147{
148 if (tick_nohz_full_enabled())
149 cpumask_or(mask, mask, tick_nohz_full_mask);
150}
151
152static inline int housekeeping_any_cpu(void)
153{
154 return cpumask_any_and(housekeeping_mask, cpu_online_mask);
155}
156
157extern void tick_nohz_full_kick(void);
158extern void tick_nohz_full_kick_cpu(int cpu);
159extern void tick_nohz_full_kick_all(void);
160extern void __tick_nohz_task_switch(void);
161#else
162static inline int housekeeping_any_cpu(void)
163{
164 return smp_processor_id();
165}
166static inline bool tick_nohz_full_enabled(void) { return false; }
167static inline bool tick_nohz_full_cpu(int cpu) { return false; }
168static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
169static inline void tick_nohz_full_kick_cpu(int cpu) { }
170static inline void tick_nohz_full_kick(void) { }
171static inline void tick_nohz_full_kick_all(void) { }
172static inline void __tick_nohz_task_switch(void) { }
173#endif
174
175static inline const struct cpumask *housekeeping_cpumask(void)
176{
177#ifdef CONFIG_NO_HZ_FULL
178 if (tick_nohz_full_enabled())
179 return housekeeping_mask;
180#endif
181 return cpu_possible_mask;
182}
183
184static inline bool is_housekeeping_cpu(int cpu)
185{
186#ifdef CONFIG_NO_HZ_FULL
187 if (tick_nohz_full_enabled())
188 return cpumask_test_cpu(cpu, housekeeping_mask);
189#endif
190 return true;
191}
192
193static inline void housekeeping_affine(struct task_struct *t)
194{
195#ifdef CONFIG_NO_HZ_FULL
196 if (tick_nohz_full_enabled())
197 set_cpus_allowed_ptr(t, housekeeping_mask);
198
199#endif
200}
201
202static inline void tick_nohz_task_switch(void)
203{
204 if (tick_nohz_full_enabled())
205 __tick_nohz_task_switch();
206}
207
208#endif