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 */
tick_init(void)24 static inline void tick_init(void) { }
tick_suspend_local(void)25 static inline void tick_suspend_local(void) { }
tick_resume_local(void)26 static inline void tick_resume_local(void) { }
tick_handover_do_timer(void)27 static inline void tick_handover_do_timer(void) { }
tick_cleanup_dead_cpu(int cpu)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
tick_freeze(void)35 static inline void tick_freeze(void) { }
tick_unfreeze(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
tick_irq_enter(void)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
hotplug_cpu__broadcast_tick_pull(int dead_cpu)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
tick_broadcast_control(enum tick_broadcast_mode mode)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
tick_broadcast_oneshot_control(enum tick_broadcast_state state)74 static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state)
75 {
76 	return 0;
77 }
78 #endif
79 
tick_broadcast_enable(void)80 static inline void tick_broadcast_enable(void)
81 {
82 	tick_broadcast_control(TICK_BROADCAST_ON);
83 }
tick_broadcast_disable(void)84 static inline void tick_broadcast_disable(void)
85 {
86 	tick_broadcast_control(TICK_BROADCAST_OFF);
87 }
tick_broadcast_force(void)88 static inline void tick_broadcast_force(void)
89 {
90 	tick_broadcast_control(TICK_BROADCAST_FORCE);
91 }
tick_broadcast_enter(void)92 static inline int tick_broadcast_enter(void)
93 {
94 	return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER);
95 }
tick_broadcast_exit(void)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 	TICK_DEP_BIT_RCU		= 4
107 };
108 
109 #define TICK_DEP_MASK_NONE		0
110 #define TICK_DEP_MASK_POSIX_TIMER	(1 << TICK_DEP_BIT_POSIX_TIMER)
111 #define TICK_DEP_MASK_PERF_EVENTS	(1 << TICK_DEP_BIT_PERF_EVENTS)
112 #define TICK_DEP_MASK_SCHED		(1 << TICK_DEP_BIT_SCHED)
113 #define TICK_DEP_MASK_CLOCK_UNSTABLE	(1 << TICK_DEP_BIT_CLOCK_UNSTABLE)
114 #define TICK_DEP_MASK_RCU		(1 << TICK_DEP_BIT_RCU)
115 
116 #ifdef CONFIG_NO_HZ_COMMON
117 extern bool tick_nohz_enabled;
118 extern bool tick_nohz_tick_stopped(void);
119 extern bool tick_nohz_tick_stopped_cpu(int cpu);
120 extern void tick_nohz_idle_stop_tick(void);
121 extern void tick_nohz_idle_retain_tick(void);
122 extern void tick_nohz_idle_restart_tick(void);
123 extern void tick_nohz_idle_enter(void);
124 extern void tick_nohz_idle_exit(void);
125 extern void tick_nohz_irq_exit(void);
126 extern bool tick_nohz_idle_got_tick(void);
127 extern ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next);
128 extern unsigned long tick_nohz_get_idle_calls(void);
129 extern unsigned long tick_nohz_get_idle_calls_cpu(int cpu);
130 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
131 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
132 
tick_nohz_idle_stop_tick_protected(void)133 static inline void tick_nohz_idle_stop_tick_protected(void)
134 {
135 	local_irq_disable();
136 	tick_nohz_idle_stop_tick();
137 	local_irq_enable();
138 }
139 
140 #else /* !CONFIG_NO_HZ_COMMON */
141 #define tick_nohz_enabled (0)
tick_nohz_tick_stopped(void)142 static inline int tick_nohz_tick_stopped(void) { return 0; }
tick_nohz_tick_stopped_cpu(int cpu)143 static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; }
tick_nohz_idle_stop_tick(void)144 static inline void tick_nohz_idle_stop_tick(void) { }
tick_nohz_idle_retain_tick(void)145 static inline void tick_nohz_idle_retain_tick(void) { }
tick_nohz_idle_restart_tick(void)146 static inline void tick_nohz_idle_restart_tick(void) { }
tick_nohz_idle_enter(void)147 static inline void tick_nohz_idle_enter(void) { }
tick_nohz_idle_exit(void)148 static inline void tick_nohz_idle_exit(void) { }
tick_nohz_idle_got_tick(void)149 static inline bool tick_nohz_idle_got_tick(void) { return false; }
150 
tick_nohz_get_sleep_length(ktime_t * delta_next)151 static inline ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next)
152 {
153 	*delta_next = TICK_NSEC;
154 	return *delta_next;
155 }
get_cpu_idle_time_us(int cpu,u64 * unused)156 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
get_cpu_iowait_time_us(int cpu,u64 * unused)157 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
158 
tick_nohz_idle_stop_tick_protected(void)159 static inline void tick_nohz_idle_stop_tick_protected(void) { }
160 #endif /* !CONFIG_NO_HZ_COMMON */
161 
162 #ifdef CONFIG_NO_HZ_FULL
163 extern bool tick_nohz_full_running;
164 extern cpumask_var_t tick_nohz_full_mask;
165 
tick_nohz_full_enabled(void)166 static inline bool tick_nohz_full_enabled(void)
167 {
168 	if (!context_tracking_is_enabled())
169 		return false;
170 
171 	return tick_nohz_full_running;
172 }
173 
tick_nohz_full_cpu(int cpu)174 static inline bool tick_nohz_full_cpu(int cpu)
175 {
176 	if (!tick_nohz_full_enabled())
177 		return false;
178 
179 	return cpumask_test_cpu(cpu, tick_nohz_full_mask);
180 }
181 
tick_nohz_full_add_cpus_to(struct cpumask * mask)182 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
183 {
184 	if (tick_nohz_full_enabled())
185 		cpumask_or(mask, mask, tick_nohz_full_mask);
186 }
187 
188 extern void tick_nohz_dep_set(enum tick_dep_bits bit);
189 extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
190 extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
191 extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
192 extern void tick_nohz_dep_set_task(struct task_struct *tsk,
193 				   enum tick_dep_bits bit);
194 extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
195 				     enum tick_dep_bits bit);
196 extern void tick_nohz_dep_set_signal(struct signal_struct *signal,
197 				     enum tick_dep_bits bit);
198 extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
199 				       enum tick_dep_bits bit);
200 extern bool tick_nohz_cpu_hotpluggable(unsigned int cpu);
201 
202 /*
203  * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
204  * on top of static keys.
205  */
tick_dep_set(enum tick_dep_bits bit)206 static inline void tick_dep_set(enum tick_dep_bits bit)
207 {
208 	if (tick_nohz_full_enabled())
209 		tick_nohz_dep_set(bit);
210 }
211 
tick_dep_clear(enum tick_dep_bits bit)212 static inline void tick_dep_clear(enum tick_dep_bits bit)
213 {
214 	if (tick_nohz_full_enabled())
215 		tick_nohz_dep_clear(bit);
216 }
217 
tick_dep_set_cpu(int cpu,enum tick_dep_bits bit)218 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
219 {
220 	if (tick_nohz_full_cpu(cpu))
221 		tick_nohz_dep_set_cpu(cpu, bit);
222 }
223 
tick_dep_clear_cpu(int cpu,enum tick_dep_bits bit)224 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
225 {
226 	if (tick_nohz_full_cpu(cpu))
227 		tick_nohz_dep_clear_cpu(cpu, bit);
228 }
229 
tick_dep_set_task(struct task_struct * tsk,enum tick_dep_bits bit)230 static inline void tick_dep_set_task(struct task_struct *tsk,
231 				     enum tick_dep_bits bit)
232 {
233 	if (tick_nohz_full_enabled())
234 		tick_nohz_dep_set_task(tsk, bit);
235 }
tick_dep_clear_task(struct task_struct * tsk,enum tick_dep_bits bit)236 static inline void tick_dep_clear_task(struct task_struct *tsk,
237 				       enum tick_dep_bits bit)
238 {
239 	if (tick_nohz_full_enabled())
240 		tick_nohz_dep_clear_task(tsk, bit);
241 }
tick_dep_set_signal(struct signal_struct * signal,enum tick_dep_bits bit)242 static inline void tick_dep_set_signal(struct signal_struct *signal,
243 				       enum tick_dep_bits bit)
244 {
245 	if (tick_nohz_full_enabled())
246 		tick_nohz_dep_set_signal(signal, bit);
247 }
tick_dep_clear_signal(struct signal_struct * signal,enum tick_dep_bits bit)248 static inline void tick_dep_clear_signal(struct signal_struct *signal,
249 					 enum tick_dep_bits bit)
250 {
251 	if (tick_nohz_full_enabled())
252 		tick_nohz_dep_clear_signal(signal, bit);
253 }
254 
255 extern void tick_nohz_full_kick_cpu(int cpu);
256 extern void __tick_nohz_task_switch(void);
257 extern void __init tick_nohz_full_setup(cpumask_var_t cpumask);
258 #else
tick_nohz_full_enabled(void)259 static inline bool tick_nohz_full_enabled(void) { return false; }
tick_nohz_full_cpu(int cpu)260 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
tick_nohz_full_add_cpus_to(struct cpumask * mask)261 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
262 
tick_nohz_dep_set_cpu(int cpu,enum tick_dep_bits bit)263 static inline void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
tick_nohz_dep_clear_cpu(int cpu,enum tick_dep_bits bit)264 static inline void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
tick_nohz_cpu_hotpluggable(unsigned int cpu)265 static inline bool tick_nohz_cpu_hotpluggable(unsigned int cpu) { return true; }
266 
tick_dep_set(enum tick_dep_bits bit)267 static inline void tick_dep_set(enum tick_dep_bits bit) { }
tick_dep_clear(enum tick_dep_bits bit)268 static inline void tick_dep_clear(enum tick_dep_bits bit) { }
tick_dep_set_cpu(int cpu,enum tick_dep_bits bit)269 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
tick_dep_clear_cpu(int cpu,enum tick_dep_bits bit)270 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
tick_dep_set_task(struct task_struct * tsk,enum tick_dep_bits bit)271 static inline void tick_dep_set_task(struct task_struct *tsk,
272 				     enum tick_dep_bits bit) { }
tick_dep_clear_task(struct task_struct * tsk,enum tick_dep_bits bit)273 static inline void tick_dep_clear_task(struct task_struct *tsk,
274 				       enum tick_dep_bits bit) { }
tick_dep_set_signal(struct signal_struct * signal,enum tick_dep_bits bit)275 static inline void tick_dep_set_signal(struct signal_struct *signal,
276 				       enum tick_dep_bits bit) { }
tick_dep_clear_signal(struct signal_struct * signal,enum tick_dep_bits bit)277 static inline void tick_dep_clear_signal(struct signal_struct *signal,
278 					 enum tick_dep_bits bit) { }
279 
tick_nohz_full_kick_cpu(int cpu)280 static inline void tick_nohz_full_kick_cpu(int cpu) { }
__tick_nohz_task_switch(void)281 static inline void __tick_nohz_task_switch(void) { }
tick_nohz_full_setup(cpumask_var_t cpumask)282 static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { }
283 #endif
284 
tick_nohz_task_switch(void)285 static inline void tick_nohz_task_switch(void)
286 {
287 	if (tick_nohz_full_enabled())
288 		__tick_nohz_task_switch();
289 }
290 
291 #endif
292