xref: /linux-6.15/include/linux/tick.h (revision 13e792a1)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Tick related global functions
4  */
5 #ifndef _LINUX_TICK_H
6 #define _LINUX_TICK_H
7 
8 #include <linux/clockchips.h>
9 #include <linux/irqflags.h>
10 #include <linux/percpu.h>
11 #include <linux/context_tracking_state.h>
12 #include <linux/cpumask.h>
13 #include <linux/sched.h>
14 
15 #ifdef CONFIG_GENERIC_CLOCKEVENTS
16 extern void __init tick_init(void);
17 /* Should be core only, but ARM BL switcher requires it */
18 extern void tick_suspend_local(void);
19 /* Should be core only, but XEN resume magic and ARM BL switcher require it */
20 extern void tick_resume_local(void);
21 extern void tick_handover_do_timer(void);
22 extern void tick_cleanup_dead_cpu(int cpu);
23 #else /* CONFIG_GENERIC_CLOCKEVENTS */
24 static inline void tick_init(void) { }
25 static inline void tick_suspend_local(void) { }
26 static inline void tick_resume_local(void) { }
27 static inline void tick_handover_do_timer(void) { }
28 static inline void tick_cleanup_dead_cpu(int cpu) { }
29 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */
30 
31 #if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_SUSPEND)
32 extern void tick_freeze(void);
33 extern void tick_unfreeze(void);
34 #else
35 static inline void tick_freeze(void) { }
36 static inline void tick_unfreeze(void) { }
37 #endif
38 
39 #ifdef CONFIG_TICK_ONESHOT
40 extern void tick_irq_enter(void);
41 #  ifndef arch_needs_cpu
42 #   define arch_needs_cpu() (0)
43 #  endif
44 # else
45 static inline void tick_irq_enter(void) { }
46 #endif
47 
48 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
49 extern void hotplug_cpu__broadcast_tick_pull(int dead_cpu);
50 #else
51 static inline void hotplug_cpu__broadcast_tick_pull(int dead_cpu) { }
52 #endif
53 
54 enum tick_broadcast_mode {
55 	TICK_BROADCAST_OFF,
56 	TICK_BROADCAST_ON,
57 	TICK_BROADCAST_FORCE,
58 };
59 
60 enum tick_broadcast_state {
61 	TICK_BROADCAST_EXIT,
62 	TICK_BROADCAST_ENTER,
63 };
64 
65 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
66 extern void tick_broadcast_control(enum tick_broadcast_mode mode);
67 #else
68 static inline void tick_broadcast_control(enum tick_broadcast_mode mode) { }
69 #endif /* BROADCAST */
70 
71 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_HOTPLUG_CPU)
72 extern void tick_offline_cpu(unsigned int cpu);
73 #else
74 static inline void tick_offline_cpu(unsigned int cpu) { }
75 #endif
76 
77 #ifdef CONFIG_GENERIC_CLOCKEVENTS
78 extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state);
79 #else
80 static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state)
81 {
82 	return 0;
83 }
84 #endif
85 
86 static inline void tick_broadcast_enable(void)
87 {
88 	tick_broadcast_control(TICK_BROADCAST_ON);
89 }
90 static inline void tick_broadcast_disable(void)
91 {
92 	tick_broadcast_control(TICK_BROADCAST_OFF);
93 }
94 static inline void tick_broadcast_force(void)
95 {
96 	tick_broadcast_control(TICK_BROADCAST_FORCE);
97 }
98 static inline int tick_broadcast_enter(void)
99 {
100 	return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER);
101 }
102 static inline void tick_broadcast_exit(void)
103 {
104 	tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT);
105 }
106 
107 enum tick_dep_bits {
108 	TICK_DEP_BIT_POSIX_TIMER	= 0,
109 	TICK_DEP_BIT_PERF_EVENTS	= 1,
110 	TICK_DEP_BIT_SCHED		= 2,
111 	TICK_DEP_BIT_CLOCK_UNSTABLE	= 3
112 };
113 
114 #define TICK_DEP_MASK_NONE		0
115 #define TICK_DEP_MASK_POSIX_TIMER	(1 << TICK_DEP_BIT_POSIX_TIMER)
116 #define TICK_DEP_MASK_PERF_EVENTS	(1 << TICK_DEP_BIT_PERF_EVENTS)
117 #define TICK_DEP_MASK_SCHED		(1 << TICK_DEP_BIT_SCHED)
118 #define TICK_DEP_MASK_CLOCK_UNSTABLE	(1 << TICK_DEP_BIT_CLOCK_UNSTABLE)
119 
120 #ifdef CONFIG_NO_HZ_COMMON
121 extern bool tick_nohz_enabled;
122 extern bool tick_nohz_tick_stopped(void);
123 extern bool tick_nohz_tick_stopped_cpu(int cpu);
124 extern void tick_nohz_idle_stop_tick(void);
125 extern void tick_nohz_idle_retain_tick(void);
126 extern void tick_nohz_idle_restart_tick(void);
127 extern void tick_nohz_idle_enter(void);
128 extern void tick_nohz_idle_exit(void);
129 extern void tick_nohz_irq_exit(void);
130 extern bool tick_nohz_idle_got_tick(void);
131 extern ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next);
132 extern unsigned long tick_nohz_get_idle_calls(void);
133 extern unsigned long tick_nohz_get_idle_calls_cpu(int cpu);
134 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
135 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
136 
137 static inline void tick_nohz_idle_stop_tick_protected(void)
138 {
139 	local_irq_disable();
140 	tick_nohz_idle_stop_tick();
141 	local_irq_enable();
142 }
143 
144 #else /* !CONFIG_NO_HZ_COMMON */
145 #define tick_nohz_enabled (0)
146 static inline int tick_nohz_tick_stopped(void) { return 0; }
147 static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; }
148 static inline void tick_nohz_idle_stop_tick(void) { }
149 static inline void tick_nohz_idle_retain_tick(void) { }
150 static inline void tick_nohz_idle_restart_tick(void) { }
151 static inline void tick_nohz_idle_enter(void) { }
152 static inline void tick_nohz_idle_exit(void) { }
153 static inline bool tick_nohz_idle_got_tick(void) { return false; }
154 
155 static inline ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next)
156 {
157 	*delta_next = TICK_NSEC;
158 	return *delta_next;
159 }
160 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
161 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
162 
163 static inline void tick_nohz_idle_stop_tick_protected(void) { }
164 #endif /* !CONFIG_NO_HZ_COMMON */
165 
166 #ifdef CONFIG_NO_HZ_FULL
167 extern bool tick_nohz_full_running;
168 extern cpumask_var_t tick_nohz_full_mask;
169 
170 static inline bool tick_nohz_full_enabled(void)
171 {
172 	if (!context_tracking_is_enabled())
173 		return false;
174 
175 	return tick_nohz_full_running;
176 }
177 
178 static inline bool tick_nohz_full_cpu(int cpu)
179 {
180 	if (!tick_nohz_full_enabled())
181 		return false;
182 
183 	return cpumask_test_cpu(cpu, tick_nohz_full_mask);
184 }
185 
186 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
187 {
188 	if (tick_nohz_full_enabled())
189 		cpumask_or(mask, mask, tick_nohz_full_mask);
190 }
191 
192 extern void tick_nohz_dep_set(enum tick_dep_bits bit);
193 extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
194 extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
195 extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
196 extern void tick_nohz_dep_set_task(struct task_struct *tsk,
197 				   enum tick_dep_bits bit);
198 extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
199 				     enum tick_dep_bits bit);
200 extern void tick_nohz_dep_set_signal(struct signal_struct *signal,
201 				     enum tick_dep_bits bit);
202 extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
203 				       enum tick_dep_bits bit);
204 
205 /*
206  * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
207  * on top of static keys.
208  */
209 static inline void tick_dep_set(enum tick_dep_bits bit)
210 {
211 	if (tick_nohz_full_enabled())
212 		tick_nohz_dep_set(bit);
213 }
214 
215 static inline void tick_dep_clear(enum tick_dep_bits bit)
216 {
217 	if (tick_nohz_full_enabled())
218 		tick_nohz_dep_clear(bit);
219 }
220 
221 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
222 {
223 	if (tick_nohz_full_cpu(cpu))
224 		tick_nohz_dep_set_cpu(cpu, bit);
225 }
226 
227 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
228 {
229 	if (tick_nohz_full_cpu(cpu))
230 		tick_nohz_dep_clear_cpu(cpu, bit);
231 }
232 
233 static inline void tick_dep_set_task(struct task_struct *tsk,
234 				     enum tick_dep_bits bit)
235 {
236 	if (tick_nohz_full_enabled())
237 		tick_nohz_dep_set_task(tsk, bit);
238 }
239 static inline void tick_dep_clear_task(struct task_struct *tsk,
240 				       enum tick_dep_bits bit)
241 {
242 	if (tick_nohz_full_enabled())
243 		tick_nohz_dep_clear_task(tsk, bit);
244 }
245 static inline void tick_dep_set_signal(struct signal_struct *signal,
246 				       enum tick_dep_bits bit)
247 {
248 	if (tick_nohz_full_enabled())
249 		tick_nohz_dep_set_signal(signal, bit);
250 }
251 static inline void tick_dep_clear_signal(struct signal_struct *signal,
252 					 enum tick_dep_bits bit)
253 {
254 	if (tick_nohz_full_enabled())
255 		tick_nohz_dep_clear_signal(signal, bit);
256 }
257 
258 extern void tick_nohz_full_kick_cpu(int cpu);
259 extern void __tick_nohz_task_switch(void);
260 extern void __init tick_nohz_full_setup(cpumask_var_t cpumask);
261 #else
262 static inline bool tick_nohz_full_enabled(void) { return false; }
263 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
264 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
265 
266 static inline void tick_dep_set(enum tick_dep_bits bit) { }
267 static inline void tick_dep_clear(enum tick_dep_bits bit) { }
268 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
269 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
270 static inline void tick_dep_set_task(struct task_struct *tsk,
271 				     enum tick_dep_bits bit) { }
272 static inline void tick_dep_clear_task(struct task_struct *tsk,
273 				       enum tick_dep_bits bit) { }
274 static inline void tick_dep_set_signal(struct signal_struct *signal,
275 				       enum tick_dep_bits bit) { }
276 static inline void tick_dep_clear_signal(struct signal_struct *signal,
277 					 enum tick_dep_bits bit) { }
278 
279 static inline void tick_nohz_full_kick_cpu(int cpu) { }
280 static inline void __tick_nohz_task_switch(void) { }
281 static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { }
282 #endif
283 
284 static inline void tick_nohz_task_switch(void)
285 {
286 	if (tick_nohz_full_enabled())
287 		__tick_nohz_task_switch();
288 }
289 
290 #endif
291