xref: /openbmc/linux/include/linux/tick.h (revision e5f586c763a079349398e2b0c7c271386193ac34)
1 /*
2  * Tick related global functions
3  */
4 #ifndef _LINUX_TICK_H
5 #define _LINUX_TICK_H
6 
7 #include <linux/clockchips.h>
8 #include <linux/irqflags.h>
9 #include <linux/percpu.h>
10 #include <linux/context_tracking_state.h>
11 #include <linux/cpumask.h>
12 #include <linux/sched.h>
13 
14 #ifdef CONFIG_GENERIC_CLOCKEVENTS
15 extern void __init tick_init(void);
16 /* Should be core only, but ARM BL switcher requires it */
17 extern void tick_suspend_local(void);
18 /* Should be core only, but XEN resume magic and ARM BL switcher require it */
19 extern void tick_resume_local(void);
20 extern void tick_handover_do_timer(void);
21 extern void tick_cleanup_dead_cpu(int cpu);
22 #else /* CONFIG_GENERIC_CLOCKEVENTS */
23 static inline void tick_init(void) { }
24 static inline void tick_suspend_local(void) { }
25 static inline void tick_resume_local(void) { }
26 static inline void tick_handover_do_timer(void) { }
27 static inline void tick_cleanup_dead_cpu(int cpu) { }
28 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */
29 
30 #if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_SUSPEND)
31 extern void tick_freeze(void);
32 extern void tick_unfreeze(void);
33 #else
34 static inline void tick_freeze(void) { }
35 static inline void tick_unfreeze(void) { }
36 #endif
37 
38 #ifdef CONFIG_TICK_ONESHOT
39 extern void tick_irq_enter(void);
40 #  ifndef arch_needs_cpu
41 #   define arch_needs_cpu() (0)
42 #  endif
43 # else
44 static inline void tick_irq_enter(void) { }
45 #endif
46 
47 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
48 extern void hotplug_cpu__broadcast_tick_pull(int dead_cpu);
49 #else
50 static inline void hotplug_cpu__broadcast_tick_pull(int dead_cpu) { }
51 #endif
52 
53 enum tick_broadcast_mode {
54 	TICK_BROADCAST_OFF,
55 	TICK_BROADCAST_ON,
56 	TICK_BROADCAST_FORCE,
57 };
58 
59 enum tick_broadcast_state {
60 	TICK_BROADCAST_EXIT,
61 	TICK_BROADCAST_ENTER,
62 };
63 
64 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
65 extern void tick_broadcast_control(enum tick_broadcast_mode mode);
66 #else
67 static inline void tick_broadcast_control(enum tick_broadcast_mode mode) { }
68 #endif /* BROADCAST */
69 
70 #ifdef CONFIG_GENERIC_CLOCKEVENTS
71 extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state);
72 #else
73 static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state)
74 {
75 	return 0;
76 }
77 #endif
78 
79 static inline void tick_broadcast_enable(void)
80 {
81 	tick_broadcast_control(TICK_BROADCAST_ON);
82 }
83 static inline void tick_broadcast_disable(void)
84 {
85 	tick_broadcast_control(TICK_BROADCAST_OFF);
86 }
87 static inline void tick_broadcast_force(void)
88 {
89 	tick_broadcast_control(TICK_BROADCAST_FORCE);
90 }
91 static inline int tick_broadcast_enter(void)
92 {
93 	return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER);
94 }
95 static inline void tick_broadcast_exit(void)
96 {
97 	tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT);
98 }
99 
100 enum tick_dep_bits {
101 	TICK_DEP_BIT_POSIX_TIMER	= 0,
102 	TICK_DEP_BIT_PERF_EVENTS	= 1,
103 	TICK_DEP_BIT_SCHED		= 2,
104 	TICK_DEP_BIT_CLOCK_UNSTABLE	= 3
105 };
106 
107 #define TICK_DEP_MASK_NONE		0
108 #define TICK_DEP_MASK_POSIX_TIMER	(1 << TICK_DEP_BIT_POSIX_TIMER)
109 #define TICK_DEP_MASK_PERF_EVENTS	(1 << TICK_DEP_BIT_PERF_EVENTS)
110 #define TICK_DEP_MASK_SCHED		(1 << TICK_DEP_BIT_SCHED)
111 #define TICK_DEP_MASK_CLOCK_UNSTABLE	(1 << TICK_DEP_BIT_CLOCK_UNSTABLE)
112 
113 #ifdef CONFIG_NO_HZ_COMMON
114 extern bool tick_nohz_enabled;
115 extern int tick_nohz_tick_stopped(void);
116 extern void tick_nohz_idle_enter(void);
117 extern void tick_nohz_idle_exit(void);
118 extern void tick_nohz_irq_exit(void);
119 extern ktime_t tick_nohz_get_sleep_length(void);
120 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
121 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
122 #else /* !CONFIG_NO_HZ_COMMON */
123 #define tick_nohz_enabled (0)
124 static inline int tick_nohz_tick_stopped(void) { return 0; }
125 static inline void tick_nohz_idle_enter(void) { }
126 static inline void tick_nohz_idle_exit(void) { }
127 
128 static inline ktime_t tick_nohz_get_sleep_length(void)
129 {
130 	return NSEC_PER_SEC / HZ;
131 }
132 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
133 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
134 #endif /* !CONFIG_NO_HZ_COMMON */
135 
136 #ifdef CONFIG_NO_HZ_FULL
137 extern bool tick_nohz_full_running;
138 extern cpumask_var_t tick_nohz_full_mask;
139 extern cpumask_var_t housekeeping_mask;
140 
141 static inline bool tick_nohz_full_enabled(void)
142 {
143 	if (!context_tracking_is_enabled())
144 		return false;
145 
146 	return tick_nohz_full_running;
147 }
148 
149 static inline bool tick_nohz_full_cpu(int cpu)
150 {
151 	if (!tick_nohz_full_enabled())
152 		return false;
153 
154 	return cpumask_test_cpu(cpu, tick_nohz_full_mask);
155 }
156 
157 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
158 {
159 	if (tick_nohz_full_enabled())
160 		cpumask_or(mask, mask, tick_nohz_full_mask);
161 }
162 
163 static inline int housekeeping_any_cpu(void)
164 {
165 	return cpumask_any_and(housekeeping_mask, cpu_online_mask);
166 }
167 
168 extern void tick_nohz_dep_set(enum tick_dep_bits bit);
169 extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
170 extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
171 extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
172 extern void tick_nohz_dep_set_task(struct task_struct *tsk,
173 				   enum tick_dep_bits bit);
174 extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
175 				     enum tick_dep_bits bit);
176 extern void tick_nohz_dep_set_signal(struct signal_struct *signal,
177 				     enum tick_dep_bits bit);
178 extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
179 				       enum tick_dep_bits bit);
180 
181 /*
182  * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
183  * on top of static keys.
184  */
185 static inline void tick_dep_set(enum tick_dep_bits bit)
186 {
187 	if (tick_nohz_full_enabled())
188 		tick_nohz_dep_set(bit);
189 }
190 
191 static inline void tick_dep_clear(enum tick_dep_bits bit)
192 {
193 	if (tick_nohz_full_enabled())
194 		tick_nohz_dep_clear(bit);
195 }
196 
197 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
198 {
199 	if (tick_nohz_full_cpu(cpu))
200 		tick_nohz_dep_set_cpu(cpu, bit);
201 }
202 
203 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
204 {
205 	if (tick_nohz_full_cpu(cpu))
206 		tick_nohz_dep_clear_cpu(cpu, bit);
207 }
208 
209 static inline void tick_dep_set_task(struct task_struct *tsk,
210 				     enum tick_dep_bits bit)
211 {
212 	if (tick_nohz_full_enabled())
213 		tick_nohz_dep_set_task(tsk, bit);
214 }
215 static inline void tick_dep_clear_task(struct task_struct *tsk,
216 				       enum tick_dep_bits bit)
217 {
218 	if (tick_nohz_full_enabled())
219 		tick_nohz_dep_clear_task(tsk, bit);
220 }
221 static inline void tick_dep_set_signal(struct signal_struct *signal,
222 				       enum tick_dep_bits bit)
223 {
224 	if (tick_nohz_full_enabled())
225 		tick_nohz_dep_set_signal(signal, bit);
226 }
227 static inline void tick_dep_clear_signal(struct signal_struct *signal,
228 					 enum tick_dep_bits bit)
229 {
230 	if (tick_nohz_full_enabled())
231 		tick_nohz_dep_clear_signal(signal, bit);
232 }
233 
234 extern void tick_nohz_full_kick_cpu(int cpu);
235 extern void __tick_nohz_task_switch(void);
236 #else
237 static inline int housekeeping_any_cpu(void)
238 {
239 	return smp_processor_id();
240 }
241 static inline bool tick_nohz_full_enabled(void) { return false; }
242 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
243 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
244 
245 static inline void tick_dep_set(enum tick_dep_bits bit) { }
246 static inline void tick_dep_clear(enum tick_dep_bits bit) { }
247 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
248 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
249 static inline void tick_dep_set_task(struct task_struct *tsk,
250 				     enum tick_dep_bits bit) { }
251 static inline void tick_dep_clear_task(struct task_struct *tsk,
252 				       enum tick_dep_bits bit) { }
253 static inline void tick_dep_set_signal(struct signal_struct *signal,
254 				       enum tick_dep_bits bit) { }
255 static inline void tick_dep_clear_signal(struct signal_struct *signal,
256 					 enum tick_dep_bits bit) { }
257 
258 static inline void tick_nohz_full_kick_cpu(int cpu) { }
259 static inline void __tick_nohz_task_switch(void) { }
260 #endif
261 
262 static inline const struct cpumask *housekeeping_cpumask(void)
263 {
264 #ifdef CONFIG_NO_HZ_FULL
265 	if (tick_nohz_full_enabled())
266 		return housekeeping_mask;
267 #endif
268 	return cpu_possible_mask;
269 }
270 
271 static inline bool is_housekeeping_cpu(int cpu)
272 {
273 #ifdef CONFIG_NO_HZ_FULL
274 	if (tick_nohz_full_enabled())
275 		return cpumask_test_cpu(cpu, housekeeping_mask);
276 #endif
277 	return true;
278 }
279 
280 static inline void housekeeping_affine(struct task_struct *t)
281 {
282 #ifdef CONFIG_NO_HZ_FULL
283 	if (tick_nohz_full_enabled())
284 		set_cpus_allowed_ptr(t, housekeeping_mask);
285 
286 #endif
287 }
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