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 | #include <linux/static_key.h> |
16 | |
17 | #ifdef CONFIG_GENERIC_CLOCKEVENTS |
18 | extern void __init tick_init(void); |
19 | /* Should be core only, but ARM BL switcher requires it */ |
20 | extern void tick_suspend_local(void); |
21 | /* Should be core only, but XEN resume magic and ARM BL switcher require it */ |
22 | extern void tick_resume_local(void); |
23 | extern void tick_cleanup_dead_cpu(int cpu); |
24 | #else /* CONFIG_GENERIC_CLOCKEVENTS */ |
25 | static inline void tick_init(void) { } |
26 | static inline void tick_suspend_local(void) { } |
27 | static inline void tick_resume_local(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_HOTPLUG_CPU) |
32 | extern int tick_cpu_dying(unsigned int cpu); |
33 | extern void tick_assert_timekeeping_handover(void); |
34 | #else |
35 | #define tick_cpu_dying NULL |
36 | static inline void tick_assert_timekeeping_handover(void) { } |
37 | #endif |
38 | |
39 | #if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_SUSPEND) |
40 | extern void tick_freeze(void); |
41 | extern void tick_unfreeze(void); |
42 | #else |
43 | static inline void tick_freeze(void) { } |
44 | static inline void tick_unfreeze(void) { } |
45 | #endif |
46 | |
47 | #ifdef CONFIG_TICK_ONESHOT |
48 | extern void tick_irq_enter(void); |
49 | # ifndef arch_needs_cpu |
50 | # define arch_needs_cpu() (0) |
51 | # endif |
52 | # else |
53 | static inline void tick_irq_enter(void) { } |
54 | #endif |
55 | |
56 | #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT) |
57 | extern void hotplug_cpu__broadcast_tick_pull(int dead_cpu); |
58 | #else |
59 | static inline void hotplug_cpu__broadcast_tick_pull(int dead_cpu) { } |
60 | #endif |
61 | |
62 | enum tick_broadcast_mode { |
63 | TICK_BROADCAST_OFF, |
64 | TICK_BROADCAST_ON, |
65 | TICK_BROADCAST_FORCE, |
66 | }; |
67 | |
68 | enum tick_broadcast_state { |
69 | TICK_BROADCAST_EXIT, |
70 | TICK_BROADCAST_ENTER, |
71 | }; |
72 | |
73 | extern struct static_key_false arch_needs_tick_broadcast; |
74 | |
75 | #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST |
76 | extern void tick_broadcast_control(enum tick_broadcast_mode mode); |
77 | #else |
78 | static inline void tick_broadcast_control(enum tick_broadcast_mode mode) { } |
79 | #endif /* BROADCAST */ |
80 | |
81 | #ifdef CONFIG_GENERIC_CLOCKEVENTS |
82 | extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state); |
83 | #else |
84 | static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state) |
85 | { |
86 | return 0; |
87 | } |
88 | #endif |
89 | |
90 | static inline void tick_broadcast_enable(void) |
91 | { |
92 | tick_broadcast_control(mode: TICK_BROADCAST_ON); |
93 | } |
94 | static inline void tick_broadcast_disable(void) |
95 | { |
96 | tick_broadcast_control(mode: TICK_BROADCAST_OFF); |
97 | } |
98 | static inline void tick_broadcast_force(void) |
99 | { |
100 | tick_broadcast_control(mode: TICK_BROADCAST_FORCE); |
101 | } |
102 | static inline int tick_broadcast_enter(void) |
103 | { |
104 | return tick_broadcast_oneshot_control(state: TICK_BROADCAST_ENTER); |
105 | } |
106 | static inline void tick_broadcast_exit(void) |
107 | { |
108 | tick_broadcast_oneshot_control(state: TICK_BROADCAST_EXIT); |
109 | } |
110 | |
111 | enum tick_dep_bits { |
112 | TICK_DEP_BIT_POSIX_TIMER = 0, |
113 | TICK_DEP_BIT_PERF_EVENTS = 1, |
114 | TICK_DEP_BIT_SCHED = 2, |
115 | TICK_DEP_BIT_CLOCK_UNSTABLE = 3, |
116 | TICK_DEP_BIT_RCU = 4, |
117 | TICK_DEP_BIT_RCU_EXP = 5 |
118 | }; |
119 | #define TICK_DEP_BIT_MAX TICK_DEP_BIT_RCU_EXP |
120 | |
121 | #define TICK_DEP_MASK_NONE 0 |
122 | #define TICK_DEP_MASK_POSIX_TIMER (1 << TICK_DEP_BIT_POSIX_TIMER) |
123 | #define TICK_DEP_MASK_PERF_EVENTS (1 << TICK_DEP_BIT_PERF_EVENTS) |
124 | #define TICK_DEP_MASK_SCHED (1 << TICK_DEP_BIT_SCHED) |
125 | #define TICK_DEP_MASK_CLOCK_UNSTABLE (1 << TICK_DEP_BIT_CLOCK_UNSTABLE) |
126 | #define TICK_DEP_MASK_RCU (1 << TICK_DEP_BIT_RCU) |
127 | #define TICK_DEP_MASK_RCU_EXP (1 << TICK_DEP_BIT_RCU_EXP) |
128 | |
129 | #ifdef CONFIG_NO_HZ_COMMON |
130 | extern bool tick_nohz_enabled; |
131 | extern bool tick_nohz_tick_stopped(void); |
132 | extern bool tick_nohz_tick_stopped_cpu(int cpu); |
133 | extern void tick_nohz_idle_stop_tick(void); |
134 | extern void tick_nohz_idle_retain_tick(void); |
135 | extern void tick_nohz_idle_restart_tick(void); |
136 | extern void tick_nohz_idle_enter(void); |
137 | extern void tick_nohz_idle_exit(void); |
138 | extern void tick_nohz_irq_exit(void); |
139 | extern bool tick_nohz_idle_got_tick(void); |
140 | extern ktime_t tick_nohz_get_next_hrtimer(void); |
141 | extern ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next); |
142 | extern unsigned long tick_nohz_get_idle_calls(void); |
143 | extern unsigned long tick_nohz_get_idle_calls_cpu(int cpu); |
144 | extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time); |
145 | extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time); |
146 | #else /* !CONFIG_NO_HZ_COMMON */ |
147 | #define tick_nohz_enabled (0) |
148 | static inline int tick_nohz_tick_stopped(void) { return 0; } |
149 | static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; } |
150 | static inline void tick_nohz_idle_stop_tick(void) { } |
151 | static inline void tick_nohz_idle_retain_tick(void) { } |
152 | static inline void tick_nohz_idle_restart_tick(void) { } |
153 | static inline void tick_nohz_idle_enter(void) { } |
154 | static inline void tick_nohz_idle_exit(void) { } |
155 | static inline bool tick_nohz_idle_got_tick(void) { return false; } |
156 | static inline ktime_t tick_nohz_get_next_hrtimer(void) |
157 | { |
158 | /* Next wake up is the tick period, assume it starts now */ |
159 | return ktime_add(ktime_get(), TICK_NSEC); |
160 | } |
161 | static inline ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next) |
162 | { |
163 | *delta_next = TICK_NSEC; |
164 | return *delta_next; |
165 | } |
166 | static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; } |
167 | static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; } |
168 | #endif /* !CONFIG_NO_HZ_COMMON */ |
169 | |
170 | /* |
171 | * Mask of CPUs that are nohz_full. |
172 | * |
173 | * Users should be guarded by CONFIG_NO_HZ_FULL or a tick_nohz_full_cpu() |
174 | * check. |
175 | */ |
176 | extern cpumask_var_t tick_nohz_full_mask; |
177 | |
178 | #ifdef CONFIG_NO_HZ_FULL |
179 | extern bool tick_nohz_full_running; |
180 | |
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 | |
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 | */ |
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 | |
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 | |
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 | |
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 | |
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 | } |
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 | } |
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 | } |
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 |
278 | static inline bool tick_nohz_full_enabled(void) { return false; } |
279 | static inline bool tick_nohz_full_cpu(int cpu) { return false; } |
280 | static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { } |
281 | |
282 | static inline void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit) { } |
283 | static inline void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { } |
284 | static inline bool tick_nohz_cpu_hotpluggable(unsigned int cpu) { return true; } |
285 | |
286 | static inline void tick_dep_set(enum tick_dep_bits bit) { } |
287 | static inline void tick_dep_clear(enum tick_dep_bits bit) { } |
288 | static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { } |
289 | static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { } |
290 | static inline void tick_dep_set_task(struct task_struct *tsk, |
291 | enum tick_dep_bits bit) { } |
292 | static inline void tick_dep_clear_task(struct task_struct *tsk, |
293 | enum tick_dep_bits bit) { } |
294 | static inline void tick_dep_set_signal(struct task_struct *tsk, |
295 | enum tick_dep_bits bit) { } |
296 | static inline void tick_dep_clear_signal(struct signal_struct *signal, |
297 | enum tick_dep_bits bit) { } |
298 | |
299 | static inline void tick_nohz_full_kick_cpu(int cpu) { } |
300 | static inline void __tick_nohz_task_switch(void) { } |
301 | static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { } |
302 | #endif |
303 | |
304 | static inline void tick_nohz_task_switch(void) |
305 | { |
306 | if (tick_nohz_full_enabled()) |
307 | __tick_nohz_task_switch(); |
308 | } |
309 | |
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 | |