1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Tick related global functions
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>
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 */
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_handover_do_timer(void) { }
29 static inline void tick_cleanup_dead_cpu(int cpu) { }
30 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */
32 #if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_SUSPEND)
33 extern void tick_freeze(void);
34 extern void tick_unfreeze(void);
36 static inline void tick_freeze(void) { }
37 static inline void tick_unfreeze(void) { }
40 #ifdef CONFIG_TICK_ONESHOT
41 extern void tick_irq_enter(void);
42 # ifndef arch_needs_cpu
43 # define arch_needs_cpu() (0)
46 static inline void tick_irq_enter(void) { }
49 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
50 extern void hotplug_cpu__broadcast_tick_pull(int dead_cpu);
52 static inline void hotplug_cpu__broadcast_tick_pull(int dead_cpu) { }
55 enum tick_broadcast_mode {
61 enum tick_broadcast_state {
66 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
67 extern void tick_broadcast_control(enum tick_broadcast_mode mode);
69 static inline void tick_broadcast_control(enum tick_broadcast_mode mode) { }
70 #endif /* BROADCAST */
72 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_HOTPLUG_CPU)
73 extern void tick_offline_cpu(unsigned int cpu);
75 static inline void tick_offline_cpu(unsigned int cpu) { }
78 #ifdef CONFIG_GENERIC_CLOCKEVENTS
79 extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state);
81 static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state)
87 static inline void tick_broadcast_enable(void)
89 tick_broadcast_control(TICK_BROADCAST_ON);
91 static inline void tick_broadcast_disable(void)
93 tick_broadcast_control(TICK_BROADCAST_OFF);
95 static inline void tick_broadcast_force(void)
97 tick_broadcast_control(TICK_BROADCAST_FORCE);
99 static inline int tick_broadcast_enter(void)
101 return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER);
103 static inline void tick_broadcast_exit(void)
105 tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT);
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
116 #define TICK_DEP_BIT_MAX TICK_DEP_BIT_RCU_EXP
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)
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 #else /* !CONFIG_NO_HZ_COMMON */
144 #define tick_nohz_enabled (0)
145 static inline int tick_nohz_tick_stopped(void) { return 0; }
146 static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; }
147 static inline void tick_nohz_idle_stop_tick(void) { }
148 static inline void tick_nohz_idle_retain_tick(void) { }
149 static inline void tick_nohz_idle_restart_tick(void) { }
150 static inline void tick_nohz_idle_enter(void) { }
151 static inline void tick_nohz_idle_exit(void) { }
152 static inline bool tick_nohz_idle_got_tick(void) { return false; }
153 static inline ktime_t tick_nohz_get_next_hrtimer(void)
155 /* Next wake up is the tick period, assume it starts now */
156 return ktime_add(ktime_get(), TICK_NSEC);
158 static inline ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next)
160 *delta_next = TICK_NSEC;
163 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
164 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
165 #endif /* !CONFIG_NO_HZ_COMMON */
168 * Mask of CPUs that are nohz_full.
170 * Users should be guarded by CONFIG_NO_HZ_FULL or a tick_nohz_full_cpu()
173 extern cpumask_var_t tick_nohz_full_mask;
175 #ifdef CONFIG_NO_HZ_FULL
176 extern bool tick_nohz_full_running;
178 static inline bool tick_nohz_full_enabled(void)
180 if (!context_tracking_enabled())
183 return tick_nohz_full_running;
187 * Check if a CPU is part of the nohz_full subset. Arrange for evaluating
188 * the cpu expression (typically smp_processor_id()) _after_ the static
191 #define tick_nohz_full_cpu(_cpu) ({ \
192 bool __ret = false; \
193 if (tick_nohz_full_enabled()) \
194 __ret = cpumask_test_cpu((_cpu), tick_nohz_full_mask); \
198 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
200 if (tick_nohz_full_enabled())
201 cpumask_or(mask, mask, tick_nohz_full_mask);
204 extern void tick_nohz_dep_set(enum tick_dep_bits bit);
205 extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
206 extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
207 extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
208 extern void tick_nohz_dep_set_task(struct task_struct *tsk,
209 enum tick_dep_bits bit);
210 extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
211 enum tick_dep_bits bit);
212 extern void tick_nohz_dep_set_signal(struct task_struct *tsk,
213 enum tick_dep_bits bit);
214 extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
215 enum tick_dep_bits bit);
216 extern bool tick_nohz_cpu_hotpluggable(unsigned int cpu);
219 * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
220 * on top of static keys.
222 static inline void tick_dep_set(enum tick_dep_bits bit)
224 if (tick_nohz_full_enabled())
225 tick_nohz_dep_set(bit);
228 static inline void tick_dep_clear(enum tick_dep_bits bit)
230 if (tick_nohz_full_enabled())
231 tick_nohz_dep_clear(bit);
234 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
236 if (tick_nohz_full_cpu(cpu))
237 tick_nohz_dep_set_cpu(cpu, bit);
240 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
242 if (tick_nohz_full_cpu(cpu))
243 tick_nohz_dep_clear_cpu(cpu, bit);
246 static inline void tick_dep_set_task(struct task_struct *tsk,
247 enum tick_dep_bits bit)
249 if (tick_nohz_full_enabled())
250 tick_nohz_dep_set_task(tsk, bit);
252 static inline void tick_dep_clear_task(struct task_struct *tsk,
253 enum tick_dep_bits bit)
255 if (tick_nohz_full_enabled())
256 tick_nohz_dep_clear_task(tsk, bit);
258 static inline void tick_dep_set_signal(struct task_struct *tsk,
259 enum tick_dep_bits bit)
261 if (tick_nohz_full_enabled())
262 tick_nohz_dep_set_signal(tsk, bit);
264 static inline void tick_dep_clear_signal(struct signal_struct *signal,
265 enum tick_dep_bits bit)
267 if (tick_nohz_full_enabled())
268 tick_nohz_dep_clear_signal(signal, bit);
271 extern void tick_nohz_full_kick_cpu(int cpu);
272 extern void __tick_nohz_task_switch(void);
273 extern void __init tick_nohz_full_setup(cpumask_var_t cpumask);
275 static inline bool tick_nohz_full_enabled(void) { return false; }
276 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
277 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
279 static inline void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
280 static inline void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
281 static inline bool tick_nohz_cpu_hotpluggable(unsigned int cpu) { return true; }
283 static inline void tick_dep_set(enum tick_dep_bits bit) { }
284 static inline void tick_dep_clear(enum tick_dep_bits bit) { }
285 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
286 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
287 static inline void tick_dep_set_task(struct task_struct *tsk,
288 enum tick_dep_bits bit) { }
289 static inline void tick_dep_clear_task(struct task_struct *tsk,
290 enum tick_dep_bits bit) { }
291 static inline void tick_dep_set_signal(struct task_struct *tsk,
292 enum tick_dep_bits bit) { }
293 static inline void tick_dep_clear_signal(struct signal_struct *signal,
294 enum tick_dep_bits bit) { }
296 static inline void tick_nohz_full_kick_cpu(int cpu) { }
297 static inline void __tick_nohz_task_switch(void) { }
298 static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { }
301 static inline void tick_nohz_task_switch(void)
303 if (tick_nohz_full_enabled())
304 __tick_nohz_task_switch();
307 static inline void tick_nohz_user_enter_prepare(void)
309 if (tick_nohz_full_cpu(smp_processor_id()))
310 rcu_nocb_flush_deferred_wakeup();