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 #include <linux/rcupdate.h>
15
16 #ifdef CONFIG_GENERIC_CLOCKEVENTS
17 extern void __init tick_init(void);
18 /* Should be core only, but ARM BL switcher requires it */
19 extern void tick_suspend_local(void);
20 /* Should be core only, but XEN resume magic and ARM BL switcher require it */
21 extern void tick_resume_local(void);
22 extern void tick_handover_do_timer(void);
23 extern void tick_cleanup_dead_cpu(int cpu);
24 #else /* CONFIG_GENERIC_CLOCKEVENTS */
tick_init(void)25 static inline void tick_init(void) { }
tick_suspend_local(void)26 static inline void tick_suspend_local(void) { }
tick_resume_local(void)27 static inline void tick_resume_local(void) { }
tick_handover_do_timer(void)28 static inline void tick_handover_do_timer(void) { }
tick_cleanup_dead_cpu(int cpu)29 static inline void tick_cleanup_dead_cpu(int cpu) { }
30 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */
31
32 #if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_SUSPEND)
33 extern void tick_freeze(void);
34 extern void tick_unfreeze(void);
35 #else
tick_freeze(void)36 static inline void tick_freeze(void) { }
tick_unfreeze(void)37 static inline void tick_unfreeze(void) { }
38 #endif
39
40 #ifdef CONFIG_TICK_ONESHOT
41 extern void tick_irq_enter(void);
42 # ifndef arch_needs_cpu
43 # define arch_needs_cpu() (0)
44 # endif
45 # else
tick_irq_enter(void)46 static inline void tick_irq_enter(void) { }
47 #endif
48
49 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
50 extern void hotplug_cpu__broadcast_tick_pull(int dead_cpu);
51 #else
hotplug_cpu__broadcast_tick_pull(int dead_cpu)52 static inline void hotplug_cpu__broadcast_tick_pull(int dead_cpu) { }
53 #endif
54
55 enum tick_broadcast_mode {
56 TICK_BROADCAST_OFF,
57 TICK_BROADCAST_ON,
58 TICK_BROADCAST_FORCE,
59 };
60
61 enum tick_broadcast_state {
62 TICK_BROADCAST_EXIT,
63 TICK_BROADCAST_ENTER,
64 };
65
66 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
67 extern void tick_broadcast_control(enum tick_broadcast_mode mode);
68 #else
tick_broadcast_control(enum tick_broadcast_mode mode)69 static inline void tick_broadcast_control(enum tick_broadcast_mode mode) { }
70 #endif /* BROADCAST */
71
72 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_HOTPLUG_CPU)
73 extern void tick_offline_cpu(unsigned int cpu);
74 #else
tick_offline_cpu(unsigned int cpu)75 static inline void tick_offline_cpu(unsigned int cpu) { }
76 #endif
77
78 #ifdef CONFIG_GENERIC_CLOCKEVENTS
79 extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state);
80 #else
tick_broadcast_oneshot_control(enum tick_broadcast_state state)81 static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state)
82 {
83 return 0;
84 }
85 #endif
86
tick_broadcast_enable(void)87 static inline void tick_broadcast_enable(void)
88 {
89 tick_broadcast_control(TICK_BROADCAST_ON);
90 }
tick_broadcast_disable(void)91 static inline void tick_broadcast_disable(void)
92 {
93 tick_broadcast_control(TICK_BROADCAST_OFF);
94 }
tick_broadcast_force(void)95 static inline void tick_broadcast_force(void)
96 {
97 tick_broadcast_control(TICK_BROADCAST_FORCE);
98 }
tick_broadcast_enter(void)99 static inline int tick_broadcast_enter(void)
100 {
101 return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER);
102 }
tick_broadcast_exit(void)103 static inline void tick_broadcast_exit(void)
104 {
105 tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT);
106 }
107
108 enum tick_dep_bits {
109 TICK_DEP_BIT_POSIX_TIMER = 0,
110 TICK_DEP_BIT_PERF_EVENTS = 1,
111 TICK_DEP_BIT_SCHED = 2,
112 TICK_DEP_BIT_CLOCK_UNSTABLE = 3,
113 TICK_DEP_BIT_RCU = 4,
114 TICK_DEP_BIT_RCU_EXP = 5
115 };
116 #define TICK_DEP_BIT_MAX TICK_DEP_BIT_RCU_EXP
117
118 #define TICK_DEP_MASK_NONE 0
119 #define TICK_DEP_MASK_POSIX_TIMER (1 << TICK_DEP_BIT_POSIX_TIMER)
120 #define TICK_DEP_MASK_PERF_EVENTS (1 << TICK_DEP_BIT_PERF_EVENTS)
121 #define TICK_DEP_MASK_SCHED (1 << TICK_DEP_BIT_SCHED)
122 #define TICK_DEP_MASK_CLOCK_UNSTABLE (1 << TICK_DEP_BIT_CLOCK_UNSTABLE)
123 #define TICK_DEP_MASK_RCU (1 << TICK_DEP_BIT_RCU)
124 #define TICK_DEP_MASK_RCU_EXP (1 << TICK_DEP_BIT_RCU_EXP)
125
126 #ifdef CONFIG_NO_HZ_COMMON
127 extern bool tick_nohz_enabled;
128 extern bool tick_nohz_tick_stopped(void);
129 extern bool tick_nohz_tick_stopped_cpu(int cpu);
130 extern void tick_nohz_idle_stop_tick(void);
131 extern void tick_nohz_idle_retain_tick(void);
132 extern void tick_nohz_idle_restart_tick(void);
133 extern void tick_nohz_idle_enter(void);
134 extern void tick_nohz_idle_exit(void);
135 extern void tick_nohz_irq_exit(void);
136 extern bool tick_nohz_idle_got_tick(void);
137 extern ktime_t tick_nohz_get_next_hrtimer(void);
138 extern ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next);
139 extern unsigned long tick_nohz_get_idle_calls(void);
140 extern unsigned long tick_nohz_get_idle_calls_cpu(int cpu);
141 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
142 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
143
tick_nohz_idle_stop_tick_protected(void)144 static inline void tick_nohz_idle_stop_tick_protected(void)
145 {
146 local_irq_disable();
147 tick_nohz_idle_stop_tick();
148 local_irq_enable();
149 }
150
151 #else /* !CONFIG_NO_HZ_COMMON */
152 #define tick_nohz_enabled (0)
tick_nohz_tick_stopped(void)153 static inline int tick_nohz_tick_stopped(void) { return 0; }
tick_nohz_tick_stopped_cpu(int cpu)154 static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; }
tick_nohz_idle_stop_tick(void)155 static inline void tick_nohz_idle_stop_tick(void) { }
tick_nohz_idle_retain_tick(void)156 static inline void tick_nohz_idle_retain_tick(void) { }
tick_nohz_idle_restart_tick(void)157 static inline void tick_nohz_idle_restart_tick(void) { }
tick_nohz_idle_enter(void)158 static inline void tick_nohz_idle_enter(void) { }
tick_nohz_idle_exit(void)159 static inline void tick_nohz_idle_exit(void) { }
tick_nohz_idle_got_tick(void)160 static inline bool tick_nohz_idle_got_tick(void) { return false; }
tick_nohz_get_next_hrtimer(void)161 static inline ktime_t tick_nohz_get_next_hrtimer(void)
162 {
163 /* Next wake up is the tick period, assume it starts now */
164 return ktime_add(ktime_get(), TICK_NSEC);
165 }
tick_nohz_get_sleep_length(ktime_t * delta_next)166 static inline ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next)
167 {
168 *delta_next = TICK_NSEC;
169 return *delta_next;
170 }
get_cpu_idle_time_us(int cpu,u64 * unused)171 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
get_cpu_iowait_time_us(int cpu,u64 * unused)172 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
173
tick_nohz_idle_stop_tick_protected(void)174 static inline void tick_nohz_idle_stop_tick_protected(void) { }
175 #endif /* !CONFIG_NO_HZ_COMMON */
176
177 #ifdef CONFIG_NO_HZ_FULL
178 extern bool tick_nohz_full_running;
179 extern cpumask_var_t tick_nohz_full_mask;
180
tick_nohz_full_enabled(void)181 static inline bool tick_nohz_full_enabled(void)
182 {
183 if (!context_tracking_enabled())
184 return false;
185
186 return tick_nohz_full_running;
187 }
188
189 /*
190 * Check if a CPU is part of the nohz_full subset. Arrange for evaluating
191 * the cpu expression (typically smp_processor_id()) _after_ the static
192 * key.
193 */
194 #define tick_nohz_full_cpu(_cpu) ({ \
195 bool __ret = false; \
196 if (tick_nohz_full_enabled()) \
197 __ret = cpumask_test_cpu((_cpu), tick_nohz_full_mask); \
198 __ret; \
199 })
200
tick_nohz_full_add_cpus_to(struct cpumask * mask)201 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
202 {
203 if (tick_nohz_full_enabled())
204 cpumask_or(mask, mask, tick_nohz_full_mask);
205 }
206
207 extern void tick_nohz_dep_set(enum tick_dep_bits bit);
208 extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
209 extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
210 extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
211 extern void tick_nohz_dep_set_task(struct task_struct *tsk,
212 enum tick_dep_bits bit);
213 extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
214 enum tick_dep_bits bit);
215 extern void tick_nohz_dep_set_signal(struct task_struct *tsk,
216 enum tick_dep_bits bit);
217 extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
218 enum tick_dep_bits bit);
219 extern bool tick_nohz_cpu_hotpluggable(unsigned int cpu);
220
221 /*
222 * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
223 * on top of static keys.
224 */
tick_dep_set(enum tick_dep_bits bit)225 static inline void tick_dep_set(enum tick_dep_bits bit)
226 {
227 if (tick_nohz_full_enabled())
228 tick_nohz_dep_set(bit);
229 }
230
tick_dep_clear(enum tick_dep_bits bit)231 static inline void tick_dep_clear(enum tick_dep_bits bit)
232 {
233 if (tick_nohz_full_enabled())
234 tick_nohz_dep_clear(bit);
235 }
236
tick_dep_set_cpu(int cpu,enum tick_dep_bits bit)237 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
238 {
239 if (tick_nohz_full_cpu(cpu))
240 tick_nohz_dep_set_cpu(cpu, bit);
241 }
242
tick_dep_clear_cpu(int cpu,enum tick_dep_bits bit)243 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
244 {
245 if (tick_nohz_full_cpu(cpu))
246 tick_nohz_dep_clear_cpu(cpu, bit);
247 }
248
tick_dep_set_task(struct task_struct * tsk,enum tick_dep_bits bit)249 static inline void tick_dep_set_task(struct task_struct *tsk,
250 enum tick_dep_bits bit)
251 {
252 if (tick_nohz_full_enabled())
253 tick_nohz_dep_set_task(tsk, bit);
254 }
tick_dep_clear_task(struct task_struct * tsk,enum tick_dep_bits bit)255 static inline void tick_dep_clear_task(struct task_struct *tsk,
256 enum tick_dep_bits bit)
257 {
258 if (tick_nohz_full_enabled())
259 tick_nohz_dep_clear_task(tsk, bit);
260 }
tick_dep_set_signal(struct task_struct * tsk,enum tick_dep_bits bit)261 static inline void tick_dep_set_signal(struct task_struct *tsk,
262 enum tick_dep_bits bit)
263 {
264 if (tick_nohz_full_enabled())
265 tick_nohz_dep_set_signal(tsk, bit);
266 }
tick_dep_clear_signal(struct signal_struct * signal,enum tick_dep_bits bit)267 static inline void tick_dep_clear_signal(struct signal_struct *signal,
268 enum tick_dep_bits bit)
269 {
270 if (tick_nohz_full_enabled())
271 tick_nohz_dep_clear_signal(signal, bit);
272 }
273
274 extern void tick_nohz_full_kick_cpu(int cpu);
275 extern void __tick_nohz_task_switch(void);
276 extern void __init tick_nohz_full_setup(cpumask_var_t cpumask);
277 #else
tick_nohz_full_enabled(void)278 static inline bool tick_nohz_full_enabled(void) { return false; }
tick_nohz_full_cpu(int cpu)279 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
tick_nohz_full_add_cpus_to(struct cpumask * mask)280 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
281
tick_nohz_dep_set_cpu(int cpu,enum tick_dep_bits bit)282 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)283 static inline void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
tick_nohz_cpu_hotpluggable(unsigned int cpu)284 static inline bool tick_nohz_cpu_hotpluggable(unsigned int cpu) { return true; }
285
tick_dep_set(enum tick_dep_bits bit)286 static inline void tick_dep_set(enum tick_dep_bits bit) { }
tick_dep_clear(enum tick_dep_bits bit)287 static inline void tick_dep_clear(enum tick_dep_bits bit) { }
tick_dep_set_cpu(int cpu,enum tick_dep_bits bit)288 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)289 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)290 static inline void tick_dep_set_task(struct task_struct *tsk,
291 enum tick_dep_bits bit) { }
tick_dep_clear_task(struct task_struct * tsk,enum tick_dep_bits bit)292 static inline void tick_dep_clear_task(struct task_struct *tsk,
293 enum tick_dep_bits bit) { }
tick_dep_set_signal(struct task_struct * tsk,enum tick_dep_bits bit)294 static inline void tick_dep_set_signal(struct task_struct *tsk,
295 enum tick_dep_bits bit) { }
tick_dep_clear_signal(struct signal_struct * signal,enum tick_dep_bits bit)296 static inline void tick_dep_clear_signal(struct signal_struct *signal,
297 enum tick_dep_bits bit) { }
298
tick_nohz_full_kick_cpu(int cpu)299 static inline void tick_nohz_full_kick_cpu(int cpu) { }
__tick_nohz_task_switch(void)300 static inline void __tick_nohz_task_switch(void) { }
tick_nohz_full_setup(cpumask_var_t cpumask)301 static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { }
302 #endif
303
tick_nohz_task_switch(void)304 static inline void tick_nohz_task_switch(void)
305 {
306 if (tick_nohz_full_enabled())
307 __tick_nohz_task_switch();
308 }
309
tick_nohz_user_enter_prepare(void)310 static inline void tick_nohz_user_enter_prepare(void)
311 {
312 if (tick_nohz_full_cpu(smp_processor_id()))
313 rcu_nocb_flush_deferred_wakeup();
314 }
315
316 #endif
317