xref: /openbmc/linux/include/linux/tick.h (revision f519cd13)
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 	TICK_DEP_BIT_RCU		= 4
113 };
114 
115 #define TICK_DEP_MASK_NONE		0
116 #define TICK_DEP_MASK_POSIX_TIMER	(1 << TICK_DEP_BIT_POSIX_TIMER)
117 #define TICK_DEP_MASK_PERF_EVENTS	(1 << TICK_DEP_BIT_PERF_EVENTS)
118 #define TICK_DEP_MASK_SCHED		(1 << TICK_DEP_BIT_SCHED)
119 #define TICK_DEP_MASK_CLOCK_UNSTABLE	(1 << TICK_DEP_BIT_CLOCK_UNSTABLE)
120 #define TICK_DEP_MASK_RCU		(1 << TICK_DEP_BIT_RCU)
121 
122 #ifdef CONFIG_NO_HZ_COMMON
123 extern bool tick_nohz_enabled;
124 extern bool tick_nohz_tick_stopped(void);
125 extern bool tick_nohz_tick_stopped_cpu(int cpu);
126 extern void tick_nohz_idle_stop_tick(void);
127 extern void tick_nohz_idle_retain_tick(void);
128 extern void tick_nohz_idle_restart_tick(void);
129 extern void tick_nohz_idle_enter(void);
130 extern void tick_nohz_idle_exit(void);
131 extern void tick_nohz_irq_exit(void);
132 extern bool tick_nohz_idle_got_tick(void);
133 extern ktime_t tick_nohz_get_next_hrtimer(void);
134 extern ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next);
135 extern unsigned long tick_nohz_get_idle_calls(void);
136 extern unsigned long tick_nohz_get_idle_calls_cpu(int cpu);
137 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
138 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
139 
140 static inline void tick_nohz_idle_stop_tick_protected(void)
141 {
142 	local_irq_disable();
143 	tick_nohz_idle_stop_tick();
144 	local_irq_enable();
145 }
146 
147 #else /* !CONFIG_NO_HZ_COMMON */
148 #define tick_nohz_enabled (0)
149 static inline int tick_nohz_tick_stopped(void) { return 0; }
150 static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; }
151 static inline void tick_nohz_idle_stop_tick(void) { }
152 static inline void tick_nohz_idle_retain_tick(void) { }
153 static inline void tick_nohz_idle_restart_tick(void) { }
154 static inline void tick_nohz_idle_enter(void) { }
155 static inline void tick_nohz_idle_exit(void) { }
156 static inline bool tick_nohz_idle_got_tick(void) { return false; }
157 static inline ktime_t tick_nohz_get_next_hrtimer(void)
158 {
159 	/* Next wake up is the tick period, assume it starts now */
160 	return ktime_add(ktime_get(), TICK_NSEC);
161 }
162 static inline ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next)
163 {
164 	*delta_next = TICK_NSEC;
165 	return *delta_next;
166 }
167 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
168 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
169 
170 static inline void tick_nohz_idle_stop_tick_protected(void) { }
171 #endif /* !CONFIG_NO_HZ_COMMON */
172 
173 #ifdef CONFIG_NO_HZ_FULL
174 extern bool tick_nohz_full_running;
175 extern cpumask_var_t tick_nohz_full_mask;
176 
177 static inline bool tick_nohz_full_enabled(void)
178 {
179 	if (!context_tracking_enabled())
180 		return false;
181 
182 	return tick_nohz_full_running;
183 }
184 
185 static inline bool tick_nohz_full_cpu(int cpu)
186 {
187 	if (!tick_nohz_full_enabled())
188 		return false;
189 
190 	return cpumask_test_cpu(cpu, tick_nohz_full_mask);
191 }
192 
193 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
194 {
195 	if (tick_nohz_full_enabled())
196 		cpumask_or(mask, mask, tick_nohz_full_mask);
197 }
198 
199 extern void tick_nohz_dep_set(enum tick_dep_bits bit);
200 extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
201 extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
202 extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
203 extern void tick_nohz_dep_set_task(struct task_struct *tsk,
204 				   enum tick_dep_bits bit);
205 extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
206 				     enum tick_dep_bits bit);
207 extern void tick_nohz_dep_set_signal(struct signal_struct *signal,
208 				     enum tick_dep_bits bit);
209 extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
210 				       enum tick_dep_bits bit);
211 
212 /*
213  * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
214  * on top of static keys.
215  */
216 static inline void tick_dep_set(enum tick_dep_bits bit)
217 {
218 	if (tick_nohz_full_enabled())
219 		tick_nohz_dep_set(bit);
220 }
221 
222 static inline void tick_dep_clear(enum tick_dep_bits bit)
223 {
224 	if (tick_nohz_full_enabled())
225 		tick_nohz_dep_clear(bit);
226 }
227 
228 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
229 {
230 	if (tick_nohz_full_cpu(cpu))
231 		tick_nohz_dep_set_cpu(cpu, bit);
232 }
233 
234 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
235 {
236 	if (tick_nohz_full_cpu(cpu))
237 		tick_nohz_dep_clear_cpu(cpu, bit);
238 }
239 
240 static inline void tick_dep_set_task(struct task_struct *tsk,
241 				     enum tick_dep_bits bit)
242 {
243 	if (tick_nohz_full_enabled())
244 		tick_nohz_dep_set_task(tsk, bit);
245 }
246 static inline void tick_dep_clear_task(struct task_struct *tsk,
247 				       enum tick_dep_bits bit)
248 {
249 	if (tick_nohz_full_enabled())
250 		tick_nohz_dep_clear_task(tsk, bit);
251 }
252 static inline void tick_dep_set_signal(struct signal_struct *signal,
253 				       enum tick_dep_bits bit)
254 {
255 	if (tick_nohz_full_enabled())
256 		tick_nohz_dep_set_signal(signal, bit);
257 }
258 static inline void tick_dep_clear_signal(struct signal_struct *signal,
259 					 enum tick_dep_bits bit)
260 {
261 	if (tick_nohz_full_enabled())
262 		tick_nohz_dep_clear_signal(signal, bit);
263 }
264 
265 extern void tick_nohz_full_kick_cpu(int cpu);
266 extern void __tick_nohz_task_switch(void);
267 extern void __init tick_nohz_full_setup(cpumask_var_t cpumask);
268 #else
269 static inline bool tick_nohz_full_enabled(void) { return false; }
270 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
271 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
272 
273 static inline void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
274 static inline void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
275 
276 static inline void tick_dep_set(enum tick_dep_bits bit) { }
277 static inline void tick_dep_clear(enum tick_dep_bits bit) { }
278 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
279 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
280 static inline void tick_dep_set_task(struct task_struct *tsk,
281 				     enum tick_dep_bits bit) { }
282 static inline void tick_dep_clear_task(struct task_struct *tsk,
283 				       enum tick_dep_bits bit) { }
284 static inline void tick_dep_set_signal(struct signal_struct *signal,
285 				       enum tick_dep_bits bit) { }
286 static inline void tick_dep_clear_signal(struct signal_struct *signal,
287 					 enum tick_dep_bits bit) { }
288 
289 static inline void tick_nohz_full_kick_cpu(int cpu) { }
290 static inline void __tick_nohz_task_switch(void) { }
291 static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { }
292 #endif
293 
294 static inline void tick_nohz_task_switch(void)
295 {
296 	if (tick_nohz_full_enabled())
297 		__tick_nohz_task_switch();
298 }
299 
300 #endif
301