xref: /openbmc/linux/include/linux/tick.h (revision 2c684d89)
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 /* Should be core only, but ARM BL switcher requires it */
17 extern void tick_suspend_local(void);
18 /* Should be core only, but XEN resume magic and ARM BL switcher require it */
19 extern void tick_resume_local(void);
20 extern void tick_handover_do_timer(void);
21 extern void tick_cleanup_dead_cpu(int cpu);
22 #else /* CONFIG_GENERIC_CLOCKEVENTS */
23 static inline void tick_init(void) { }
24 static inline void tick_suspend_local(void) { }
25 static inline void tick_resume_local(void) { }
26 static inline void tick_handover_do_timer(void) { }
27 static inline void tick_cleanup_dead_cpu(int cpu) { }
28 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */
29 
30 #if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_SUSPEND)
31 extern void tick_freeze(void);
32 extern void tick_unfreeze(void);
33 #else
34 static inline void tick_freeze(void) { }
35 static inline void tick_unfreeze(void) { }
36 #endif
37 
38 #ifdef CONFIG_TICK_ONESHOT
39 extern void tick_irq_enter(void);
40 #  ifndef arch_needs_cpu
41 #   define arch_needs_cpu() (0)
42 #  endif
43 # else
44 static inline void tick_irq_enter(void) { }
45 #endif
46 
47 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
48 extern void hotplug_cpu__broadcast_tick_pull(int dead_cpu);
49 #else
50 static inline void hotplug_cpu__broadcast_tick_pull(int dead_cpu) { }
51 #endif
52 
53 enum tick_broadcast_mode {
54 	TICK_BROADCAST_OFF,
55 	TICK_BROADCAST_ON,
56 	TICK_BROADCAST_FORCE,
57 };
58 
59 enum tick_broadcast_state {
60 	TICK_BROADCAST_EXIT,
61 	TICK_BROADCAST_ENTER,
62 };
63 
64 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
65 extern void tick_broadcast_control(enum tick_broadcast_mode mode);
66 #else
67 static inline void tick_broadcast_control(enum tick_broadcast_mode mode) { }
68 #endif /* BROADCAST */
69 
70 #ifdef CONFIG_GENERIC_CLOCKEVENTS
71 extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state);
72 #else
73 static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state)
74 {
75 	return 0;
76 }
77 #endif
78 
79 static inline void tick_broadcast_enable(void)
80 {
81 	tick_broadcast_control(TICK_BROADCAST_ON);
82 }
83 static inline void tick_broadcast_disable(void)
84 {
85 	tick_broadcast_control(TICK_BROADCAST_OFF);
86 }
87 static inline void tick_broadcast_force(void)
88 {
89 	tick_broadcast_control(TICK_BROADCAST_FORCE);
90 }
91 static inline int tick_broadcast_enter(void)
92 {
93 	return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER);
94 }
95 static inline void tick_broadcast_exit(void)
96 {
97 	tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT);
98 }
99 
100 #ifdef CONFIG_NO_HZ_COMMON
101 extern int tick_nohz_tick_stopped(void);
102 extern void tick_nohz_idle_enter(void);
103 extern void tick_nohz_idle_exit(void);
104 extern void tick_nohz_irq_exit(void);
105 extern ktime_t tick_nohz_get_sleep_length(void);
106 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
107 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
108 #else /* !CONFIG_NO_HZ_COMMON */
109 static inline int tick_nohz_tick_stopped(void) { return 0; }
110 static inline void tick_nohz_idle_enter(void) { }
111 static inline void tick_nohz_idle_exit(void) { }
112 
113 static inline ktime_t tick_nohz_get_sleep_length(void)
114 {
115 	ktime_t len = { .tv64 = NSEC_PER_SEC/HZ };
116 
117 	return len;
118 }
119 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
120 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
121 #endif /* !CONFIG_NO_HZ_COMMON */
122 
123 #ifdef CONFIG_NO_HZ_FULL
124 extern bool tick_nohz_full_running;
125 extern cpumask_var_t tick_nohz_full_mask;
126 extern cpumask_var_t housekeeping_mask;
127 
128 static inline bool tick_nohz_full_enabled(void)
129 {
130 	if (!context_tracking_is_enabled())
131 		return false;
132 
133 	return tick_nohz_full_running;
134 }
135 
136 static inline bool tick_nohz_full_cpu(int cpu)
137 {
138 	if (!tick_nohz_full_enabled())
139 		return false;
140 
141 	return cpumask_test_cpu(cpu, tick_nohz_full_mask);
142 }
143 
144 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
145 {
146 	if (tick_nohz_full_enabled())
147 		cpumask_or(mask, mask, tick_nohz_full_mask);
148 }
149 
150 static inline int housekeeping_any_cpu(void)
151 {
152 	return cpumask_any_and(housekeeping_mask, cpu_online_mask);
153 }
154 
155 extern void tick_nohz_full_kick(void);
156 extern void tick_nohz_full_kick_cpu(int cpu);
157 extern void tick_nohz_full_kick_all(void);
158 extern void __tick_nohz_task_switch(void);
159 #else
160 static inline int housekeeping_any_cpu(void)
161 {
162 	return smp_processor_id();
163 }
164 static inline bool tick_nohz_full_enabled(void) { return false; }
165 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
166 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
167 static inline void tick_nohz_full_kick_cpu(int cpu) { }
168 static inline void tick_nohz_full_kick(void) { }
169 static inline void tick_nohz_full_kick_all(void) { }
170 static inline void __tick_nohz_task_switch(void) { }
171 #endif
172 
173 static inline const struct cpumask *housekeeping_cpumask(void)
174 {
175 #ifdef CONFIG_NO_HZ_FULL
176 	if (tick_nohz_full_enabled())
177 		return housekeeping_mask;
178 #endif
179 	return cpu_possible_mask;
180 }
181 
182 static inline bool is_housekeeping_cpu(int cpu)
183 {
184 #ifdef CONFIG_NO_HZ_FULL
185 	if (tick_nohz_full_enabled())
186 		return cpumask_test_cpu(cpu, housekeeping_mask);
187 #endif
188 	return true;
189 }
190 
191 static inline void housekeeping_affine(struct task_struct *t)
192 {
193 #ifdef CONFIG_NO_HZ_FULL
194 	if (tick_nohz_full_enabled())
195 		set_cpus_allowed_ptr(t, housekeeping_mask);
196 
197 #endif
198 }
199 
200 static inline void tick_nohz_task_switch(void)
201 {
202 	if (tick_nohz_full_enabled())
203 		__tick_nohz_task_switch();
204 }
205 
206 #endif
207