xref: /openbmc/linux/include/linux/tick.h (revision b830f94f)
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_next_hrtimer(void);
132 extern ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next);
133 extern unsigned long tick_nohz_get_idle_calls(void);
134 extern unsigned long tick_nohz_get_idle_calls_cpu(int cpu);
135 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
136 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
137 
138 static inline void tick_nohz_idle_stop_tick_protected(void)
139 {
140 	local_irq_disable();
141 	tick_nohz_idle_stop_tick();
142 	local_irq_enable();
143 }
144 
145 #else /* !CONFIG_NO_HZ_COMMON */
146 #define tick_nohz_enabled (0)
147 static inline int tick_nohz_tick_stopped(void) { return 0; }
148 static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; }
149 static inline void tick_nohz_idle_stop_tick(void) { }
150 static inline void tick_nohz_idle_retain_tick(void) { }
151 static inline void tick_nohz_idle_restart_tick(void) { }
152 static inline void tick_nohz_idle_enter(void) { }
153 static inline void tick_nohz_idle_exit(void) { }
154 static inline bool tick_nohz_idle_got_tick(void) { return false; }
155 static inline ktime_t tick_nohz_get_next_hrtimer(void)
156 {
157 	/* Next wake up is the tick period, assume it starts now */
158 	return ktime_add(ktime_get(), TICK_NSEC);
159 }
160 static inline ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next)
161 {
162 	*delta_next = TICK_NSEC;
163 	return *delta_next;
164 }
165 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
166 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
167 
168 static inline void tick_nohz_idle_stop_tick_protected(void) { }
169 #endif /* !CONFIG_NO_HZ_COMMON */
170 
171 #ifdef CONFIG_NO_HZ_FULL
172 extern bool tick_nohz_full_running;
173 extern cpumask_var_t tick_nohz_full_mask;
174 
175 static inline bool tick_nohz_full_enabled(void)
176 {
177 	if (!context_tracking_is_enabled())
178 		return false;
179 
180 	return tick_nohz_full_running;
181 }
182 
183 static inline bool tick_nohz_full_cpu(int cpu)
184 {
185 	if (!tick_nohz_full_enabled())
186 		return false;
187 
188 	return cpumask_test_cpu(cpu, tick_nohz_full_mask);
189 }
190 
191 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
192 {
193 	if (tick_nohz_full_enabled())
194 		cpumask_or(mask, mask, tick_nohz_full_mask);
195 }
196 
197 extern void tick_nohz_dep_set(enum tick_dep_bits bit);
198 extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
199 extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
200 extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
201 extern void tick_nohz_dep_set_task(struct task_struct *tsk,
202 				   enum tick_dep_bits bit);
203 extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
204 				     enum tick_dep_bits bit);
205 extern void tick_nohz_dep_set_signal(struct signal_struct *signal,
206 				     enum tick_dep_bits bit);
207 extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
208 				       enum tick_dep_bits bit);
209 
210 /*
211  * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
212  * on top of static keys.
213  */
214 static inline void tick_dep_set(enum tick_dep_bits bit)
215 {
216 	if (tick_nohz_full_enabled())
217 		tick_nohz_dep_set(bit);
218 }
219 
220 static inline void tick_dep_clear(enum tick_dep_bits bit)
221 {
222 	if (tick_nohz_full_enabled())
223 		tick_nohz_dep_clear(bit);
224 }
225 
226 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
227 {
228 	if (tick_nohz_full_cpu(cpu))
229 		tick_nohz_dep_set_cpu(cpu, bit);
230 }
231 
232 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
233 {
234 	if (tick_nohz_full_cpu(cpu))
235 		tick_nohz_dep_clear_cpu(cpu, bit);
236 }
237 
238 static inline void tick_dep_set_task(struct task_struct *tsk,
239 				     enum tick_dep_bits bit)
240 {
241 	if (tick_nohz_full_enabled())
242 		tick_nohz_dep_set_task(tsk, bit);
243 }
244 static inline void tick_dep_clear_task(struct task_struct *tsk,
245 				       enum tick_dep_bits bit)
246 {
247 	if (tick_nohz_full_enabled())
248 		tick_nohz_dep_clear_task(tsk, bit);
249 }
250 static inline void tick_dep_set_signal(struct signal_struct *signal,
251 				       enum tick_dep_bits bit)
252 {
253 	if (tick_nohz_full_enabled())
254 		tick_nohz_dep_set_signal(signal, bit);
255 }
256 static inline void tick_dep_clear_signal(struct signal_struct *signal,
257 					 enum tick_dep_bits bit)
258 {
259 	if (tick_nohz_full_enabled())
260 		tick_nohz_dep_clear_signal(signal, bit);
261 }
262 
263 extern void tick_nohz_full_kick_cpu(int cpu);
264 extern void __tick_nohz_task_switch(void);
265 extern void __init tick_nohz_full_setup(cpumask_var_t cpumask);
266 #else
267 static inline bool tick_nohz_full_enabled(void) { return false; }
268 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
269 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
270 
271 static inline void tick_dep_set(enum tick_dep_bits bit) { }
272 static inline void tick_dep_clear(enum tick_dep_bits bit) { }
273 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
274 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
275 static inline void tick_dep_set_task(struct task_struct *tsk,
276 				     enum tick_dep_bits bit) { }
277 static inline void tick_dep_clear_task(struct task_struct *tsk,
278 				       enum tick_dep_bits bit) { }
279 static inline void tick_dep_set_signal(struct signal_struct *signal,
280 				       enum tick_dep_bits bit) { }
281 static inline void tick_dep_clear_signal(struct signal_struct *signal,
282 					 enum tick_dep_bits bit) { }
283 
284 static inline void tick_nohz_full_kick_cpu(int cpu) { }
285 static inline void __tick_nohz_task_switch(void) { }
286 static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { }
287 #endif
288 
289 static inline void tick_nohz_task_switch(void)
290 {
291 	if (tick_nohz_full_enabled())
292 		__tick_nohz_task_switch();
293 }
294 
295 #endif
296