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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#else /* !CONFIG_NO_HZ_COMMON */
144#define tick_nohz_enabled (0)
145static inline int tick_nohz_tick_stopped(void) { return 0; }
146static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; }
147static inline void tick_nohz_idle_stop_tick(void) { }
148static inline void tick_nohz_idle_retain_tick(void) { }
149static inline void tick_nohz_idle_restart_tick(void) { }
150static inline void tick_nohz_idle_enter(void) { }
151static inline void tick_nohz_idle_exit(void) { }
152static inline bool tick_nohz_idle_got_tick(void) { return false; }
153static inline ktime_t tick_nohz_get_next_hrtimer(void)
154{
155 /* Next wake up is the tick period, assume it starts now */
156 return ktime_add(ktime_get(), TICK_NSEC);
157}
158static inline ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next)
159{
160 *delta_next = TICK_NSEC;
161 return *delta_next;
162}
163static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
164static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
165#endif /* !CONFIG_NO_HZ_COMMON */
166
167#ifdef CONFIG_NO_HZ_FULL
168extern bool tick_nohz_full_running;
169extern cpumask_var_t tick_nohz_full_mask;
170
171static inline bool tick_nohz_full_enabled(void)
172{
173 if (!context_tracking_enabled())
174 return false;
175
176 return tick_nohz_full_running;
177}
178
179/*
180 * Check if a CPU is part of the nohz_full subset. Arrange for evaluating
181 * the cpu expression (typically smp_processor_id()) _after_ the static
182 * key.
183 */
184#define tick_nohz_full_cpu(_cpu) ({ \
185 bool __ret = false; \
186 if (tick_nohz_full_enabled()) \
187 __ret = cpumask_test_cpu((_cpu), tick_nohz_full_mask); \
188 __ret; \
189})
190
191static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
192{
193 if (tick_nohz_full_enabled())
194 cpumask_or(mask, mask, tick_nohz_full_mask);
195}
196
197extern void tick_nohz_dep_set(enum tick_dep_bits bit);
198extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
199extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
200extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
201extern void tick_nohz_dep_set_task(struct task_struct *tsk,
202 enum tick_dep_bits bit);
203extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
204 enum tick_dep_bits bit);
205extern void tick_nohz_dep_set_signal(struct task_struct *tsk,
206 enum tick_dep_bits bit);
207extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
208 enum tick_dep_bits bit);
209extern bool tick_nohz_cpu_hotpluggable(unsigned int cpu);
210
211/*
212 * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
213 * on top of static keys.
214 */
215static inline void tick_dep_set(enum tick_dep_bits bit)
216{
217 if (tick_nohz_full_enabled())
218 tick_nohz_dep_set(bit);
219}
220
221static inline void tick_dep_clear(enum tick_dep_bits bit)
222{
223 if (tick_nohz_full_enabled())
224 tick_nohz_dep_clear(bit);
225}
226
227static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
228{
229 if (tick_nohz_full_cpu(cpu))
230 tick_nohz_dep_set_cpu(cpu, bit);
231}
232
233static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
234{
235 if (tick_nohz_full_cpu(cpu))
236 tick_nohz_dep_clear_cpu(cpu, bit);
237}
238
239static inline void tick_dep_set_task(struct task_struct *tsk,
240 enum tick_dep_bits bit)
241{
242 if (tick_nohz_full_enabled())
243 tick_nohz_dep_set_task(tsk, bit);
244}
245static inline void tick_dep_clear_task(struct task_struct *tsk,
246 enum tick_dep_bits bit)
247{
248 if (tick_nohz_full_enabled())
249 tick_nohz_dep_clear_task(tsk, bit);
250}
251static inline void tick_dep_set_signal(struct task_struct *tsk,
252 enum tick_dep_bits bit)
253{
254 if (tick_nohz_full_enabled())
255 tick_nohz_dep_set_signal(tsk, bit);
256}
257static inline void tick_dep_clear_signal(struct signal_struct *signal,
258 enum tick_dep_bits bit)
259{
260 if (tick_nohz_full_enabled())
261 tick_nohz_dep_clear_signal(signal, bit);
262}
263
264extern void tick_nohz_full_kick_cpu(int cpu);
265extern void __tick_nohz_task_switch(void);
266extern void __init tick_nohz_full_setup(cpumask_var_t cpumask);
267#else
268static inline bool tick_nohz_full_enabled(void) { return false; }
269static inline bool tick_nohz_full_cpu(int cpu) { return false; }
270static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
271
272static inline void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
273static inline void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
274static inline bool tick_nohz_cpu_hotpluggable(unsigned int cpu) { return true; }
275
276static inline void tick_dep_set(enum tick_dep_bits bit) { }
277static inline void tick_dep_clear(enum tick_dep_bits bit) { }
278static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
279static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
280static inline void tick_dep_set_task(struct task_struct *tsk,
281 enum tick_dep_bits bit) { }
282static inline void tick_dep_clear_task(struct task_struct *tsk,
283 enum tick_dep_bits bit) { }
284static inline void tick_dep_set_signal(struct task_struct *tsk,
285 enum tick_dep_bits bit) { }
286static inline void tick_dep_clear_signal(struct signal_struct *signal,
287 enum tick_dep_bits bit) { }
288
289static inline void tick_nohz_full_kick_cpu(int cpu) { }
290static inline void __tick_nohz_task_switch(void) { }
291static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { }
292#endif
293
294static inline void tick_nohz_task_switch(void)
295{
296 if (tick_nohz_full_enabled())
297 __tick_nohz_task_switch();
298}
299
300static inline void tick_nohz_user_enter_prepare(void)
301{
302 if (tick_nohz_full_cpu(smp_processor_id()))
303 rcu_nocb_flush_deferred_wakeup();
304}
305
306#endif