xref: /openbmc/linux/include/linux/tick.h (revision b2441318)
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 int tick_nohz_tick_stopped(void);
117 extern void tick_nohz_idle_enter(void);
118 extern void tick_nohz_idle_exit(void);
119 extern void tick_nohz_irq_exit(void);
120 extern ktime_t tick_nohz_get_sleep_length(void);
121 extern unsigned long tick_nohz_get_idle_calls(void);
122 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
123 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
124 #else /* !CONFIG_NO_HZ_COMMON */
125 #define tick_nohz_enabled (0)
126 static inline int tick_nohz_tick_stopped(void) { return 0; }
127 static inline void tick_nohz_idle_enter(void) { }
128 static inline void tick_nohz_idle_exit(void) { }
129 
130 static inline ktime_t tick_nohz_get_sleep_length(void)
131 {
132 	return NSEC_PER_SEC / HZ;
133 }
134 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
135 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
136 #endif /* !CONFIG_NO_HZ_COMMON */
137 
138 #ifdef CONFIG_NO_HZ_FULL
139 extern bool tick_nohz_full_running;
140 extern cpumask_var_t tick_nohz_full_mask;
141 extern cpumask_var_t housekeeping_mask;
142 
143 static inline bool tick_nohz_full_enabled(void)
144 {
145 	if (!context_tracking_is_enabled())
146 		return false;
147 
148 	return tick_nohz_full_running;
149 }
150 
151 static inline bool tick_nohz_full_cpu(int cpu)
152 {
153 	if (!tick_nohz_full_enabled())
154 		return false;
155 
156 	return cpumask_test_cpu(cpu, tick_nohz_full_mask);
157 }
158 
159 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
160 {
161 	if (tick_nohz_full_enabled())
162 		cpumask_or(mask, mask, tick_nohz_full_mask);
163 }
164 
165 static inline int housekeeping_any_cpu(void)
166 {
167 	return cpumask_any_and(housekeeping_mask, cpu_online_mask);
168 }
169 
170 extern void tick_nohz_dep_set(enum tick_dep_bits bit);
171 extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
172 extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
173 extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
174 extern void tick_nohz_dep_set_task(struct task_struct *tsk,
175 				   enum tick_dep_bits bit);
176 extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
177 				     enum tick_dep_bits bit);
178 extern void tick_nohz_dep_set_signal(struct signal_struct *signal,
179 				     enum tick_dep_bits bit);
180 extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
181 				       enum tick_dep_bits bit);
182 
183 /*
184  * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
185  * on top of static keys.
186  */
187 static inline void tick_dep_set(enum tick_dep_bits bit)
188 {
189 	if (tick_nohz_full_enabled())
190 		tick_nohz_dep_set(bit);
191 }
192 
193 static inline void tick_dep_clear(enum tick_dep_bits bit)
194 {
195 	if (tick_nohz_full_enabled())
196 		tick_nohz_dep_clear(bit);
197 }
198 
199 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
200 {
201 	if (tick_nohz_full_cpu(cpu))
202 		tick_nohz_dep_set_cpu(cpu, bit);
203 }
204 
205 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
206 {
207 	if (tick_nohz_full_cpu(cpu))
208 		tick_nohz_dep_clear_cpu(cpu, bit);
209 }
210 
211 static inline void tick_dep_set_task(struct task_struct *tsk,
212 				     enum tick_dep_bits bit)
213 {
214 	if (tick_nohz_full_enabled())
215 		tick_nohz_dep_set_task(tsk, bit);
216 }
217 static inline void tick_dep_clear_task(struct task_struct *tsk,
218 				       enum tick_dep_bits bit)
219 {
220 	if (tick_nohz_full_enabled())
221 		tick_nohz_dep_clear_task(tsk, bit);
222 }
223 static inline void tick_dep_set_signal(struct signal_struct *signal,
224 				       enum tick_dep_bits bit)
225 {
226 	if (tick_nohz_full_enabled())
227 		tick_nohz_dep_set_signal(signal, bit);
228 }
229 static inline void tick_dep_clear_signal(struct signal_struct *signal,
230 					 enum tick_dep_bits bit)
231 {
232 	if (tick_nohz_full_enabled())
233 		tick_nohz_dep_clear_signal(signal, bit);
234 }
235 
236 extern void tick_nohz_full_kick_cpu(int cpu);
237 extern void __tick_nohz_task_switch(void);
238 #else
239 static inline int housekeeping_any_cpu(void)
240 {
241 	return smp_processor_id();
242 }
243 static inline bool tick_nohz_full_enabled(void) { return false; }
244 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
245 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
246 
247 static inline void tick_dep_set(enum tick_dep_bits bit) { }
248 static inline void tick_dep_clear(enum tick_dep_bits bit) { }
249 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
250 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
251 static inline void tick_dep_set_task(struct task_struct *tsk,
252 				     enum tick_dep_bits bit) { }
253 static inline void tick_dep_clear_task(struct task_struct *tsk,
254 				       enum tick_dep_bits bit) { }
255 static inline void tick_dep_set_signal(struct signal_struct *signal,
256 				       enum tick_dep_bits bit) { }
257 static inline void tick_dep_clear_signal(struct signal_struct *signal,
258 					 enum tick_dep_bits bit) { }
259 
260 static inline void tick_nohz_full_kick_cpu(int cpu) { }
261 static inline void __tick_nohz_task_switch(void) { }
262 #endif
263 
264 static inline const struct cpumask *housekeeping_cpumask(void)
265 {
266 #ifdef CONFIG_NO_HZ_FULL
267 	if (tick_nohz_full_enabled())
268 		return housekeeping_mask;
269 #endif
270 	return cpu_possible_mask;
271 }
272 
273 static inline bool is_housekeeping_cpu(int cpu)
274 {
275 #ifdef CONFIG_NO_HZ_FULL
276 	if (tick_nohz_full_enabled())
277 		return cpumask_test_cpu(cpu, housekeeping_mask);
278 #endif
279 	return true;
280 }
281 
282 static inline void housekeeping_affine(struct task_struct *t)
283 {
284 #ifdef CONFIG_NO_HZ_FULL
285 	if (tick_nohz_full_enabled())
286 		set_cpus_allowed_ptr(t, housekeeping_mask);
287 
288 #endif
289 }
290 
291 static inline void tick_nohz_task_switch(void)
292 {
293 	if (tick_nohz_full_enabled())
294 		__tick_nohz_task_switch();
295 }
296 
297 #endif
298