xref: /openbmc/linux/include/linux/tick.h (revision de3a9980)
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 	TICK_DEP_BIT_RCU_EXP		= 5
114 };
115 #define TICK_DEP_BIT_MAX TICK_DEP_BIT_RCU_EXP
116 
117 #define TICK_DEP_MASK_NONE		0
118 #define TICK_DEP_MASK_POSIX_TIMER	(1 << TICK_DEP_BIT_POSIX_TIMER)
119 #define TICK_DEP_MASK_PERF_EVENTS	(1 << TICK_DEP_BIT_PERF_EVENTS)
120 #define TICK_DEP_MASK_SCHED		(1 << TICK_DEP_BIT_SCHED)
121 #define TICK_DEP_MASK_CLOCK_UNSTABLE	(1 << TICK_DEP_BIT_CLOCK_UNSTABLE)
122 #define TICK_DEP_MASK_RCU		(1 << TICK_DEP_BIT_RCU)
123 #define TICK_DEP_MASK_RCU_EXP		(1 << TICK_DEP_BIT_RCU_EXP)
124 
125 #ifdef CONFIG_NO_HZ_COMMON
126 extern bool tick_nohz_enabled;
127 extern bool tick_nohz_tick_stopped(void);
128 extern bool tick_nohz_tick_stopped_cpu(int cpu);
129 extern void tick_nohz_idle_stop_tick(void);
130 extern void tick_nohz_idle_retain_tick(void);
131 extern void tick_nohz_idle_restart_tick(void);
132 extern void tick_nohz_idle_enter(void);
133 extern void tick_nohz_idle_exit(void);
134 extern void tick_nohz_irq_exit(void);
135 extern bool tick_nohz_idle_got_tick(void);
136 extern ktime_t tick_nohz_get_next_hrtimer(void);
137 extern ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next);
138 extern unsigned long tick_nohz_get_idle_calls(void);
139 extern unsigned long tick_nohz_get_idle_calls_cpu(int cpu);
140 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
141 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
142 
143 static inline void tick_nohz_idle_stop_tick_protected(void)
144 {
145 	local_irq_disable();
146 	tick_nohz_idle_stop_tick();
147 	local_irq_enable();
148 }
149 
150 #else /* !CONFIG_NO_HZ_COMMON */
151 #define tick_nohz_enabled (0)
152 static inline int tick_nohz_tick_stopped(void) { return 0; }
153 static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; }
154 static inline void tick_nohz_idle_stop_tick(void) { }
155 static inline void tick_nohz_idle_retain_tick(void) { }
156 static inline void tick_nohz_idle_restart_tick(void) { }
157 static inline void tick_nohz_idle_enter(void) { }
158 static inline void tick_nohz_idle_exit(void) { }
159 static inline bool tick_nohz_idle_got_tick(void) { return false; }
160 static inline ktime_t tick_nohz_get_next_hrtimer(void)
161 {
162 	/* Next wake up is the tick period, assume it starts now */
163 	return ktime_add(ktime_get(), TICK_NSEC);
164 }
165 static inline ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next)
166 {
167 	*delta_next = TICK_NSEC;
168 	return *delta_next;
169 }
170 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
171 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
172 
173 static inline void tick_nohz_idle_stop_tick_protected(void) { }
174 #endif /* !CONFIG_NO_HZ_COMMON */
175 
176 #ifdef CONFIG_NO_HZ_FULL
177 extern bool tick_nohz_full_running;
178 extern cpumask_var_t tick_nohz_full_mask;
179 
180 static inline bool tick_nohz_full_enabled(void)
181 {
182 	if (!context_tracking_enabled())
183 		return false;
184 
185 	return tick_nohz_full_running;
186 }
187 
188 static inline bool tick_nohz_full_cpu(int cpu)
189 {
190 	if (!tick_nohz_full_enabled())
191 		return false;
192 
193 	return cpumask_test_cpu(cpu, tick_nohz_full_mask);
194 }
195 
196 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
197 {
198 	if (tick_nohz_full_enabled())
199 		cpumask_or(mask, mask, tick_nohz_full_mask);
200 }
201 
202 extern void tick_nohz_dep_set(enum tick_dep_bits bit);
203 extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
204 extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
205 extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
206 extern void tick_nohz_dep_set_task(struct task_struct *tsk,
207 				   enum tick_dep_bits bit);
208 extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
209 				     enum tick_dep_bits bit);
210 extern void tick_nohz_dep_set_signal(struct signal_struct *signal,
211 				     enum tick_dep_bits bit);
212 extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
213 				       enum tick_dep_bits bit);
214 
215 /*
216  * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
217  * on top of static keys.
218  */
219 static inline void tick_dep_set(enum tick_dep_bits bit)
220 {
221 	if (tick_nohz_full_enabled())
222 		tick_nohz_dep_set(bit);
223 }
224 
225 static inline void tick_dep_clear(enum tick_dep_bits bit)
226 {
227 	if (tick_nohz_full_enabled())
228 		tick_nohz_dep_clear(bit);
229 }
230 
231 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
232 {
233 	if (tick_nohz_full_cpu(cpu))
234 		tick_nohz_dep_set_cpu(cpu, bit);
235 }
236 
237 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
238 {
239 	if (tick_nohz_full_cpu(cpu))
240 		tick_nohz_dep_clear_cpu(cpu, bit);
241 }
242 
243 static inline void tick_dep_set_task(struct task_struct *tsk,
244 				     enum tick_dep_bits bit)
245 {
246 	if (tick_nohz_full_enabled())
247 		tick_nohz_dep_set_task(tsk, bit);
248 }
249 static inline void tick_dep_clear_task(struct task_struct *tsk,
250 				       enum tick_dep_bits bit)
251 {
252 	if (tick_nohz_full_enabled())
253 		tick_nohz_dep_clear_task(tsk, bit);
254 }
255 static inline void tick_dep_set_signal(struct signal_struct *signal,
256 				       enum tick_dep_bits bit)
257 {
258 	if (tick_nohz_full_enabled())
259 		tick_nohz_dep_set_signal(signal, bit);
260 }
261 static inline void tick_dep_clear_signal(struct signal_struct *signal,
262 					 enum tick_dep_bits bit)
263 {
264 	if (tick_nohz_full_enabled())
265 		tick_nohz_dep_clear_signal(signal, bit);
266 }
267 
268 extern void tick_nohz_full_kick_cpu(int cpu);
269 extern void __tick_nohz_task_switch(void);
270 extern void __init tick_nohz_full_setup(cpumask_var_t cpumask);
271 #else
272 static inline bool tick_nohz_full_enabled(void) { return false; }
273 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
274 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
275 
276 static inline void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
277 static inline void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
278 
279 static inline void tick_dep_set(enum tick_dep_bits bit) { }
280 static inline void tick_dep_clear(enum tick_dep_bits bit) { }
281 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
282 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
283 static inline void tick_dep_set_task(struct task_struct *tsk,
284 				     enum tick_dep_bits bit) { }
285 static inline void tick_dep_clear_task(struct task_struct *tsk,
286 				       enum tick_dep_bits bit) { }
287 static inline void tick_dep_set_signal(struct signal_struct *signal,
288 				       enum tick_dep_bits bit) { }
289 static inline void tick_dep_clear_signal(struct signal_struct *signal,
290 					 enum tick_dep_bits bit) { }
291 
292 static inline void tick_nohz_full_kick_cpu(int cpu) { }
293 static inline void __tick_nohz_task_switch(void) { }
294 static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { }
295 #endif
296 
297 static inline void tick_nohz_task_switch(void)
298 {
299 	if (tick_nohz_full_enabled())
300 		__tick_nohz_task_switch();
301 }
302 
303 #endif
304