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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
17extern void __init tick_init(void);
18/* Should be core only, but ARM BL switcher requires it */
19extern void tick_suspend_local(void);
20/* Should be core only, but XEN resume magic and ARM BL switcher require it */
21extern void tick_resume_local(void);
22extern void tick_handover_do_timer(void);
23extern void tick_cleanup_dead_cpu(int cpu);
24#else /* CONFIG_GENERIC_CLOCKEVENTS */
25static inline void tick_init(void) { }
26static inline void tick_suspend_local(void) { }
27static inline void tick_resume_local(void) { }
28static inline void tick_handover_do_timer(void) { }
29static inline void tick_cleanup_dead_cpu(int cpu) { }
30#endif /* !CONFIG_GENERIC_CLOCKEVENTS */
31
32#if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_SUSPEND)
33extern void tick_freeze(void);
34extern void tick_unfreeze(void);
35#else
36static inline void tick_freeze(void) { }
37static inline void tick_unfreeze(void) { }
38#endif
39
40#ifdef CONFIG_TICK_ONESHOT
41extern void tick_irq_enter(void);
42# ifndef arch_needs_cpu
43# define arch_needs_cpu() (0)
44# endif
45# else
46static inline void tick_irq_enter(void) { }
47#endif
48
49#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
50extern void hotplug_cpu__broadcast_tick_pull(int dead_cpu);
51#else
52static inline void hotplug_cpu__broadcast_tick_pull(int dead_cpu) { }
53#endif
54
55enum tick_broadcast_mode {
56 TICK_BROADCAST_OFF,
57 TICK_BROADCAST_ON,
58 TICK_BROADCAST_FORCE,
59};
60
61enum tick_broadcast_state {
62 TICK_BROADCAST_EXIT,
63 TICK_BROADCAST_ENTER,
64};
65
66#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
67extern void tick_broadcast_control(enum tick_broadcast_mode mode);
68#else
69static 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)
73extern void tick_offline_cpu(unsigned int cpu);
74#else
75static inline void tick_offline_cpu(unsigned int cpu) { }
76#endif
77
78#ifdef CONFIG_GENERIC_CLOCKEVENTS
79extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state);
80#else
81static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state)
82{
83 return 0;
84}
85#endif
86
87static inline void tick_broadcast_enable(void)
88{
89 tick_broadcast_control(TICK_BROADCAST_ON);
90}
91static inline void tick_broadcast_disable(void)
92{
93 tick_broadcast_control(TICK_BROADCAST_OFF);
94}
95static inline void tick_broadcast_force(void)
96{
97 tick_broadcast_control(TICK_BROADCAST_FORCE);
98}
99static inline int tick_broadcast_enter(void)
100{
101 return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER);
102}
103static inline void tick_broadcast_exit(void)
104{
105 tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT);
106}
107
108enum 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
127extern bool tick_nohz_enabled;
128extern bool tick_nohz_tick_stopped(void);
129extern bool tick_nohz_tick_stopped_cpu(int cpu);
130extern void tick_nohz_idle_stop_tick(void);
131extern void tick_nohz_idle_retain_tick(void);
132extern void tick_nohz_idle_restart_tick(void);
133extern void tick_nohz_idle_enter(void);
134extern void tick_nohz_idle_exit(void);
135extern void tick_nohz_irq_exit(void);
136extern bool tick_nohz_idle_got_tick(void);
137extern ktime_t tick_nohz_get_next_hrtimer(void);
138extern ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next);
139extern unsigned long tick_nohz_get_idle_calls(void);
140extern unsigned long tick_nohz_get_idle_calls_cpu(int cpu);
141extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
142extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
143
144static 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)
153static inline int tick_nohz_tick_stopped(void) { return 0; }
154static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; }
155static inline void tick_nohz_idle_stop_tick(void) { }
156static inline void tick_nohz_idle_retain_tick(void) { }
157static inline void tick_nohz_idle_restart_tick(void) { }
158static inline void tick_nohz_idle_enter(void) { }
159static inline void tick_nohz_idle_exit(void) { }
160static inline bool tick_nohz_idle_got_tick(void) { return false; }
161static 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}
166static inline ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next)
167{
168 *delta_next = TICK_NSEC;
169 return *delta_next;
170}
171static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
172static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
173
174static inline void tick_nohz_idle_stop_tick_protected(void) { }
175#endif /* !CONFIG_NO_HZ_COMMON */
176
177#ifdef CONFIG_NO_HZ_FULL
178extern bool tick_nohz_full_running;
179extern cpumask_var_t tick_nohz_full_mask;
180
181static 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
189static inline bool tick_nohz_full_cpu(int cpu)
190{
191 if (!tick_nohz_full_enabled())
192 return false;
193
194 return cpumask_test_cpu(cpu, tick_nohz_full_mask);
195}
196
197static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
198{
199 if (tick_nohz_full_enabled())
200 cpumask_or(mask, mask, tick_nohz_full_mask);
201}
202
203extern void tick_nohz_dep_set(enum tick_dep_bits bit);
204extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
205extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
206extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
207extern void tick_nohz_dep_set_task(struct task_struct *tsk,
208 enum tick_dep_bits bit);
209extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
210 enum tick_dep_bits bit);
211extern void tick_nohz_dep_set_signal(struct signal_struct *signal,
212 enum tick_dep_bits bit);
213extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
214 enum tick_dep_bits bit);
215
216/*
217 * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
218 * on top of static keys.
219 */
220static inline void tick_dep_set(enum tick_dep_bits bit)
221{
222 if (tick_nohz_full_enabled())
223 tick_nohz_dep_set(bit);
224}
225
226static inline void tick_dep_clear(enum tick_dep_bits bit)
227{
228 if (tick_nohz_full_enabled())
229 tick_nohz_dep_clear(bit);
230}
231
232static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
233{
234 if (tick_nohz_full_cpu(cpu))
235 tick_nohz_dep_set_cpu(cpu, bit);
236}
237
238static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
239{
240 if (tick_nohz_full_cpu(cpu))
241 tick_nohz_dep_clear_cpu(cpu, bit);
242}
243
244static inline void tick_dep_set_task(struct task_struct *tsk,
245 enum tick_dep_bits bit)
246{
247 if (tick_nohz_full_enabled())
248 tick_nohz_dep_set_task(tsk, bit);
249}
250static inline void tick_dep_clear_task(struct task_struct *tsk,
251 enum tick_dep_bits bit)
252{
253 if (tick_nohz_full_enabled())
254 tick_nohz_dep_clear_task(tsk, bit);
255}
256static inline void tick_dep_set_signal(struct signal_struct *signal,
257 enum tick_dep_bits bit)
258{
259 if (tick_nohz_full_enabled())
260 tick_nohz_dep_set_signal(signal, bit);
261}
262static inline void tick_dep_clear_signal(struct signal_struct *signal,
263 enum tick_dep_bits bit)
264{
265 if (tick_nohz_full_enabled())
266 tick_nohz_dep_clear_signal(signal, bit);
267}
268
269extern void tick_nohz_full_kick_cpu(int cpu);
270extern void __tick_nohz_task_switch(void);
271extern void __init tick_nohz_full_setup(cpumask_var_t cpumask);
272#else
273static inline bool tick_nohz_full_enabled(void) { return false; }
274static inline bool tick_nohz_full_cpu(int cpu) { return false; }
275static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
276
277static inline void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
278static inline void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
279
280static inline void tick_dep_set(enum tick_dep_bits bit) { }
281static inline void tick_dep_clear(enum tick_dep_bits bit) { }
282static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
283static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
284static inline void tick_dep_set_task(struct task_struct *tsk,
285 enum tick_dep_bits bit) { }
286static inline void tick_dep_clear_task(struct task_struct *tsk,
287 enum tick_dep_bits bit) { }
288static inline void tick_dep_set_signal(struct signal_struct *signal,
289 enum tick_dep_bits bit) { }
290static inline void tick_dep_clear_signal(struct signal_struct *signal,
291 enum tick_dep_bits bit) { }
292
293static inline void tick_nohz_full_kick_cpu(int cpu) { }
294static inline void __tick_nohz_task_switch(void) { }
295static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { }
296#endif
297
298static inline void tick_nohz_task_switch(void)
299{
300 if (tick_nohz_full_enabled())
301 __tick_nohz_task_switch();
302}
303
304static inline void tick_nohz_user_enter_prepare(void)
305{
306 if (tick_nohz_full_cpu(smp_processor_id()))
307 rcu_nocb_flush_deferred_wakeup();
308}
309
310#endif