xref: /openbmc/linux/include/linux/tick.h (revision b240b419db5d624ce7a5a397d6f62a1a686009ec)
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 bool tick_nohz_tick_stopped(void);
117 extern bool tick_nohz_tick_stopped_cpu(int cpu);
118 extern void tick_nohz_idle_enter(void);
119 extern void tick_nohz_idle_exit(void);
120 extern void tick_nohz_irq_exit(void);
121 extern ktime_t tick_nohz_get_sleep_length(void);
122 extern unsigned long tick_nohz_get_idle_calls(void);
123 extern unsigned long tick_nohz_get_idle_calls_cpu(int cpu);
124 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
125 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
126 #else /* !CONFIG_NO_HZ_COMMON */
127 #define tick_nohz_enabled (0)
128 static inline int tick_nohz_tick_stopped(void) { return 0; }
129 static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; }
130 static inline void tick_nohz_idle_enter(void) { }
131 static inline void tick_nohz_idle_exit(void) { }
132 
133 static inline ktime_t tick_nohz_get_sleep_length(void)
134 {
135 	return NSEC_PER_SEC / HZ;
136 }
137 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
138 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
139 #endif /* !CONFIG_NO_HZ_COMMON */
140 
141 #ifdef CONFIG_NO_HZ_FULL
142 extern bool tick_nohz_full_running;
143 extern cpumask_var_t tick_nohz_full_mask;
144 
145 static inline bool tick_nohz_full_enabled(void)
146 {
147 	if (!context_tracking_is_enabled())
148 		return false;
149 
150 	return tick_nohz_full_running;
151 }
152 
153 static inline bool tick_nohz_full_cpu(int cpu)
154 {
155 	if (!tick_nohz_full_enabled())
156 		return false;
157 
158 	return cpumask_test_cpu(cpu, tick_nohz_full_mask);
159 }
160 
161 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
162 {
163 	if (tick_nohz_full_enabled())
164 		cpumask_or(mask, mask, tick_nohz_full_mask);
165 }
166 
167 extern void tick_nohz_dep_set(enum tick_dep_bits bit);
168 extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
169 extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
170 extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
171 extern void tick_nohz_dep_set_task(struct task_struct *tsk,
172 				   enum tick_dep_bits bit);
173 extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
174 				     enum tick_dep_bits bit);
175 extern void tick_nohz_dep_set_signal(struct signal_struct *signal,
176 				     enum tick_dep_bits bit);
177 extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
178 				       enum tick_dep_bits bit);
179 
180 /*
181  * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
182  * on top of static keys.
183  */
184 static inline void tick_dep_set(enum tick_dep_bits bit)
185 {
186 	if (tick_nohz_full_enabled())
187 		tick_nohz_dep_set(bit);
188 }
189 
190 static inline void tick_dep_clear(enum tick_dep_bits bit)
191 {
192 	if (tick_nohz_full_enabled())
193 		tick_nohz_dep_clear(bit);
194 }
195 
196 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
197 {
198 	if (tick_nohz_full_cpu(cpu))
199 		tick_nohz_dep_set_cpu(cpu, bit);
200 }
201 
202 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
203 {
204 	if (tick_nohz_full_cpu(cpu))
205 		tick_nohz_dep_clear_cpu(cpu, bit);
206 }
207 
208 static inline void tick_dep_set_task(struct task_struct *tsk,
209 				     enum tick_dep_bits bit)
210 {
211 	if (tick_nohz_full_enabled())
212 		tick_nohz_dep_set_task(tsk, bit);
213 }
214 static inline void tick_dep_clear_task(struct task_struct *tsk,
215 				       enum tick_dep_bits bit)
216 {
217 	if (tick_nohz_full_enabled())
218 		tick_nohz_dep_clear_task(tsk, bit);
219 }
220 static inline void tick_dep_set_signal(struct signal_struct *signal,
221 				       enum tick_dep_bits bit)
222 {
223 	if (tick_nohz_full_enabled())
224 		tick_nohz_dep_set_signal(signal, bit);
225 }
226 static inline void tick_dep_clear_signal(struct signal_struct *signal,
227 					 enum tick_dep_bits bit)
228 {
229 	if (tick_nohz_full_enabled())
230 		tick_nohz_dep_clear_signal(signal, bit);
231 }
232 
233 extern void tick_nohz_full_kick_cpu(int cpu);
234 extern void __tick_nohz_task_switch(void);
235 extern void __init tick_nohz_full_setup(cpumask_var_t cpumask);
236 #else
237 static inline bool tick_nohz_full_enabled(void) { return false; }
238 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
239 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
240 
241 static inline void tick_dep_set(enum tick_dep_bits bit) { }
242 static inline void tick_dep_clear(enum tick_dep_bits bit) { }
243 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
244 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
245 static inline void tick_dep_set_task(struct task_struct *tsk,
246 				     enum tick_dep_bits bit) { }
247 static inline void tick_dep_clear_task(struct task_struct *tsk,
248 				       enum tick_dep_bits bit) { }
249 static inline void tick_dep_set_signal(struct signal_struct *signal,
250 				       enum tick_dep_bits bit) { }
251 static inline void tick_dep_clear_signal(struct signal_struct *signal,
252 					 enum tick_dep_bits bit) { }
253 
254 static inline void tick_nohz_full_kick_cpu(int cpu) { }
255 static inline void __tick_nohz_task_switch(void) { }
256 static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { }
257 #endif
258 
259 static inline void tick_nohz_task_switch(void)
260 {
261 	if (tick_nohz_full_enabled())
262 		__tick_nohz_task_switch();
263 }
264 
265 #endif
266