xref: /openbmc/linux/include/linux/tick.h (revision 1c2dd16a)
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 unsigned long tick_nohz_get_idle_calls(void);
121 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
122 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
123 #else /* !CONFIG_NO_HZ_COMMON */
124 #define tick_nohz_enabled (0)
125 static inline int tick_nohz_tick_stopped(void) { return 0; }
126 static inline void tick_nohz_idle_enter(void) { }
127 static inline void tick_nohz_idle_exit(void) { }
128 
129 static inline ktime_t tick_nohz_get_sleep_length(void)
130 {
131 	return NSEC_PER_SEC / HZ;
132 }
133 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
134 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
135 #endif /* !CONFIG_NO_HZ_COMMON */
136 
137 #ifdef CONFIG_NO_HZ_FULL
138 extern bool tick_nohz_full_running;
139 extern cpumask_var_t tick_nohz_full_mask;
140 extern cpumask_var_t housekeeping_mask;
141 
142 static inline bool tick_nohz_full_enabled(void)
143 {
144 	if (!context_tracking_is_enabled())
145 		return false;
146 
147 	return tick_nohz_full_running;
148 }
149 
150 static inline bool tick_nohz_full_cpu(int cpu)
151 {
152 	if (!tick_nohz_full_enabled())
153 		return false;
154 
155 	return cpumask_test_cpu(cpu, tick_nohz_full_mask);
156 }
157 
158 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
159 {
160 	if (tick_nohz_full_enabled())
161 		cpumask_or(mask, mask, tick_nohz_full_mask);
162 }
163 
164 static inline int housekeeping_any_cpu(void)
165 {
166 	return cpumask_any_and(housekeeping_mask, cpu_online_mask);
167 }
168 
169 extern void tick_nohz_dep_set(enum tick_dep_bits bit);
170 extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
171 extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
172 extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
173 extern void tick_nohz_dep_set_task(struct task_struct *tsk,
174 				   enum tick_dep_bits bit);
175 extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
176 				     enum tick_dep_bits bit);
177 extern void tick_nohz_dep_set_signal(struct signal_struct *signal,
178 				     enum tick_dep_bits bit);
179 extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
180 				       enum tick_dep_bits bit);
181 
182 /*
183  * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
184  * on top of static keys.
185  */
186 static inline void tick_dep_set(enum tick_dep_bits bit)
187 {
188 	if (tick_nohz_full_enabled())
189 		tick_nohz_dep_set(bit);
190 }
191 
192 static inline void tick_dep_clear(enum tick_dep_bits bit)
193 {
194 	if (tick_nohz_full_enabled())
195 		tick_nohz_dep_clear(bit);
196 }
197 
198 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
199 {
200 	if (tick_nohz_full_cpu(cpu))
201 		tick_nohz_dep_set_cpu(cpu, bit);
202 }
203 
204 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
205 {
206 	if (tick_nohz_full_cpu(cpu))
207 		tick_nohz_dep_clear_cpu(cpu, bit);
208 }
209 
210 static inline void tick_dep_set_task(struct task_struct *tsk,
211 				     enum tick_dep_bits bit)
212 {
213 	if (tick_nohz_full_enabled())
214 		tick_nohz_dep_set_task(tsk, bit);
215 }
216 static inline void tick_dep_clear_task(struct task_struct *tsk,
217 				       enum tick_dep_bits bit)
218 {
219 	if (tick_nohz_full_enabled())
220 		tick_nohz_dep_clear_task(tsk, bit);
221 }
222 static inline void tick_dep_set_signal(struct signal_struct *signal,
223 				       enum tick_dep_bits bit)
224 {
225 	if (tick_nohz_full_enabled())
226 		tick_nohz_dep_set_signal(signal, bit);
227 }
228 static inline void tick_dep_clear_signal(struct signal_struct *signal,
229 					 enum tick_dep_bits bit)
230 {
231 	if (tick_nohz_full_enabled())
232 		tick_nohz_dep_clear_signal(signal, bit);
233 }
234 
235 extern void tick_nohz_full_kick_cpu(int cpu);
236 extern void __tick_nohz_task_switch(void);
237 #else
238 static inline int housekeeping_any_cpu(void)
239 {
240 	return smp_processor_id();
241 }
242 static inline bool tick_nohz_full_enabled(void) { return false; }
243 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
244 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
245 
246 static inline void tick_dep_set(enum tick_dep_bits bit) { }
247 static inline void tick_dep_clear(enum tick_dep_bits bit) { }
248 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
249 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
250 static inline void tick_dep_set_task(struct task_struct *tsk,
251 				     enum tick_dep_bits bit) { }
252 static inline void tick_dep_clear_task(struct task_struct *tsk,
253 				       enum tick_dep_bits bit) { }
254 static inline void tick_dep_set_signal(struct signal_struct *signal,
255 				       enum tick_dep_bits bit) { }
256 static inline void tick_dep_clear_signal(struct signal_struct *signal,
257 					 enum tick_dep_bits bit) { }
258 
259 static inline void tick_nohz_full_kick_cpu(int cpu) { }
260 static inline void __tick_nohz_task_switch(void) { }
261 #endif
262 
263 static inline const struct cpumask *housekeeping_cpumask(void)
264 {
265 #ifdef CONFIG_NO_HZ_FULL
266 	if (tick_nohz_full_enabled())
267 		return housekeeping_mask;
268 #endif
269 	return cpu_possible_mask;
270 }
271 
272 static inline bool is_housekeeping_cpu(int cpu)
273 {
274 #ifdef CONFIG_NO_HZ_FULL
275 	if (tick_nohz_full_enabled())
276 		return cpumask_test_cpu(cpu, housekeeping_mask);
277 #endif
278 	return true;
279 }
280 
281 static inline void housekeeping_affine(struct task_struct *t)
282 {
283 #ifdef CONFIG_NO_HZ_FULL
284 	if (tick_nohz_full_enabled())
285 		set_cpus_allowed_ptr(t, housekeeping_mask);
286 
287 #endif
288 }
289 
290 static inline void tick_nohz_task_switch(void)
291 {
292 	if (tick_nohz_full_enabled())
293 		__tick_nohz_task_switch();
294 }
295 
296 #endif
297