xref: /linux-6.15/include/linux/tick.h (revision 554c8aa8)
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 #ifdef CONFIG_GENERIC_CLOCKEVENTS
72 extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state);
73 #else
74 static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state)
75 {
76 	return 0;
77 }
78 #endif
79 
80 static inline void tick_broadcast_enable(void)
81 {
82 	tick_broadcast_control(TICK_BROADCAST_ON);
83 }
84 static inline void tick_broadcast_disable(void)
85 {
86 	tick_broadcast_control(TICK_BROADCAST_OFF);
87 }
88 static inline void tick_broadcast_force(void)
89 {
90 	tick_broadcast_control(TICK_BROADCAST_FORCE);
91 }
92 static inline int tick_broadcast_enter(void)
93 {
94 	return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER);
95 }
96 static inline void tick_broadcast_exit(void)
97 {
98 	tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT);
99 }
100 
101 enum tick_dep_bits {
102 	TICK_DEP_BIT_POSIX_TIMER	= 0,
103 	TICK_DEP_BIT_PERF_EVENTS	= 1,
104 	TICK_DEP_BIT_SCHED		= 2,
105 	TICK_DEP_BIT_CLOCK_UNSTABLE	= 3
106 };
107 
108 #define TICK_DEP_MASK_NONE		0
109 #define TICK_DEP_MASK_POSIX_TIMER	(1 << TICK_DEP_BIT_POSIX_TIMER)
110 #define TICK_DEP_MASK_PERF_EVENTS	(1 << TICK_DEP_BIT_PERF_EVENTS)
111 #define TICK_DEP_MASK_SCHED		(1 << TICK_DEP_BIT_SCHED)
112 #define TICK_DEP_MASK_CLOCK_UNSTABLE	(1 << TICK_DEP_BIT_CLOCK_UNSTABLE)
113 
114 #ifdef CONFIG_NO_HZ_COMMON
115 extern bool tick_nohz_enabled;
116 extern bool tick_nohz_tick_stopped(void);
117 extern bool tick_nohz_tick_stopped_cpu(int cpu);
118 extern void tick_nohz_idle_stop_tick(void);
119 extern void tick_nohz_idle_retain_tick(void);
120 extern void tick_nohz_idle_restart_tick(void);
121 extern void tick_nohz_idle_enter(void);
122 extern void tick_nohz_idle_exit(void);
123 extern void tick_nohz_irq_exit(void);
124 extern bool tick_nohz_idle_got_tick(void);
125 extern ktime_t tick_nohz_get_sleep_length(void);
126 extern unsigned long tick_nohz_get_idle_calls(void);
127 extern unsigned long tick_nohz_get_idle_calls_cpu(int cpu);
128 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
129 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
130 
131 static inline void tick_nohz_idle_stop_tick_protected(void)
132 {
133 	local_irq_disable();
134 	tick_nohz_idle_stop_tick();
135 	local_irq_enable();
136 }
137 
138 #else /* !CONFIG_NO_HZ_COMMON */
139 #define tick_nohz_enabled (0)
140 static inline int tick_nohz_tick_stopped(void) { return 0; }
141 static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; }
142 static inline void tick_nohz_idle_stop_tick(void) { }
143 static inline void tick_nohz_idle_retain_tick(void) { }
144 static inline void tick_nohz_idle_restart_tick(void) { }
145 static inline void tick_nohz_idle_enter(void) { }
146 static inline void tick_nohz_idle_exit(void) { }
147 static inline bool tick_nohz_idle_got_tick(void) { return false; }
148 
149 static inline ktime_t tick_nohz_get_sleep_length(void)
150 {
151 	return NSEC_PER_SEC / HZ;
152 }
153 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
154 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
155 
156 static inline void tick_nohz_idle_stop_tick_protected(void) { }
157 #endif /* !CONFIG_NO_HZ_COMMON */
158 
159 #ifdef CONFIG_NO_HZ_FULL
160 extern bool tick_nohz_full_running;
161 extern cpumask_var_t tick_nohz_full_mask;
162 
163 static inline bool tick_nohz_full_enabled(void)
164 {
165 	if (!context_tracking_is_enabled())
166 		return false;
167 
168 	return tick_nohz_full_running;
169 }
170 
171 static inline bool tick_nohz_full_cpu(int cpu)
172 {
173 	if (!tick_nohz_full_enabled())
174 		return false;
175 
176 	return cpumask_test_cpu(cpu, tick_nohz_full_mask);
177 }
178 
179 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
180 {
181 	if (tick_nohz_full_enabled())
182 		cpumask_or(mask, mask, tick_nohz_full_mask);
183 }
184 
185 extern void tick_nohz_dep_set(enum tick_dep_bits bit);
186 extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
187 extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
188 extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
189 extern void tick_nohz_dep_set_task(struct task_struct *tsk,
190 				   enum tick_dep_bits bit);
191 extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
192 				     enum tick_dep_bits bit);
193 extern void tick_nohz_dep_set_signal(struct signal_struct *signal,
194 				     enum tick_dep_bits bit);
195 extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
196 				       enum tick_dep_bits bit);
197 
198 /*
199  * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
200  * on top of static keys.
201  */
202 static inline void tick_dep_set(enum tick_dep_bits bit)
203 {
204 	if (tick_nohz_full_enabled())
205 		tick_nohz_dep_set(bit);
206 }
207 
208 static inline void tick_dep_clear(enum tick_dep_bits bit)
209 {
210 	if (tick_nohz_full_enabled())
211 		tick_nohz_dep_clear(bit);
212 }
213 
214 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
215 {
216 	if (tick_nohz_full_cpu(cpu))
217 		tick_nohz_dep_set_cpu(cpu, bit);
218 }
219 
220 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
221 {
222 	if (tick_nohz_full_cpu(cpu))
223 		tick_nohz_dep_clear_cpu(cpu, bit);
224 }
225 
226 static inline void tick_dep_set_task(struct task_struct *tsk,
227 				     enum tick_dep_bits bit)
228 {
229 	if (tick_nohz_full_enabled())
230 		tick_nohz_dep_set_task(tsk, bit);
231 }
232 static inline void tick_dep_clear_task(struct task_struct *tsk,
233 				       enum tick_dep_bits bit)
234 {
235 	if (tick_nohz_full_enabled())
236 		tick_nohz_dep_clear_task(tsk, bit);
237 }
238 static inline void tick_dep_set_signal(struct signal_struct *signal,
239 				       enum tick_dep_bits bit)
240 {
241 	if (tick_nohz_full_enabled())
242 		tick_nohz_dep_set_signal(signal, bit);
243 }
244 static inline void tick_dep_clear_signal(struct signal_struct *signal,
245 					 enum tick_dep_bits bit)
246 {
247 	if (tick_nohz_full_enabled())
248 		tick_nohz_dep_clear_signal(signal, bit);
249 }
250 
251 extern void tick_nohz_full_kick_cpu(int cpu);
252 extern void __tick_nohz_task_switch(void);
253 extern void __init tick_nohz_full_setup(cpumask_var_t cpumask);
254 #else
255 static inline bool tick_nohz_full_enabled(void) { return false; }
256 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
257 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
258 
259 static inline void tick_dep_set(enum tick_dep_bits bit) { }
260 static inline void tick_dep_clear(enum tick_dep_bits bit) { }
261 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
262 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
263 static inline void tick_dep_set_task(struct task_struct *tsk,
264 				     enum tick_dep_bits bit) { }
265 static inline void tick_dep_clear_task(struct task_struct *tsk,
266 				       enum tick_dep_bits bit) { }
267 static inline void tick_dep_set_signal(struct signal_struct *signal,
268 				       enum tick_dep_bits bit) { }
269 static inline void tick_dep_clear_signal(struct signal_struct *signal,
270 					 enum tick_dep_bits bit) { }
271 
272 static inline void tick_nohz_full_kick_cpu(int cpu) { }
273 static inline void __tick_nohz_task_switch(void) { }
274 static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { }
275 #endif
276 
277 static inline void tick_nohz_task_switch(void)
278 {
279 	if (tick_nohz_full_enabled())
280 		__tick_nohz_task_switch();
281 }
282 
283 #endif
284