tick.h (9975B)
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} 188 189/* 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 201static 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 207extern void tick_nohz_dep_set(enum tick_dep_bits bit); 208extern void tick_nohz_dep_clear(enum tick_dep_bits bit); 209extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit); 210extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit); 211extern void tick_nohz_dep_set_task(struct task_struct *tsk, 212 enum tick_dep_bits bit); 213extern void tick_nohz_dep_clear_task(struct task_struct *tsk, 214 enum tick_dep_bits bit); 215extern void tick_nohz_dep_set_signal(struct task_struct *tsk, 216 enum tick_dep_bits bit); 217extern void tick_nohz_dep_clear_signal(struct signal_struct *signal, 218 enum tick_dep_bits bit); 219 220/* 221 * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases 222 * on top of static keys. 223 */ 224static inline void tick_dep_set(enum tick_dep_bits bit) 225{ 226 if (tick_nohz_full_enabled()) 227 tick_nohz_dep_set(bit); 228} 229 230static inline void tick_dep_clear(enum tick_dep_bits bit) 231{ 232 if (tick_nohz_full_enabled()) 233 tick_nohz_dep_clear(bit); 234} 235 236static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) 237{ 238 if (tick_nohz_full_cpu(cpu)) 239 tick_nohz_dep_set_cpu(cpu, bit); 240} 241 242static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) 243{ 244 if (tick_nohz_full_cpu(cpu)) 245 tick_nohz_dep_clear_cpu(cpu, bit); 246} 247 248static inline void tick_dep_set_task(struct task_struct *tsk, 249 enum tick_dep_bits bit) 250{ 251 if (tick_nohz_full_enabled()) 252 tick_nohz_dep_set_task(tsk, bit); 253} 254static inline void tick_dep_clear_task(struct task_struct *tsk, 255 enum tick_dep_bits bit) 256{ 257 if (tick_nohz_full_enabled()) 258 tick_nohz_dep_clear_task(tsk, bit); 259} 260static inline void tick_dep_set_signal(struct task_struct *tsk, 261 enum tick_dep_bits bit) 262{ 263 if (tick_nohz_full_enabled()) 264 tick_nohz_dep_set_signal(tsk, bit); 265} 266static inline void tick_dep_clear_signal(struct signal_struct *signal, 267 enum tick_dep_bits bit) 268{ 269 if (tick_nohz_full_enabled()) 270 tick_nohz_dep_clear_signal(signal, bit); 271} 272 273extern void tick_nohz_full_kick_cpu(int cpu); 274extern void __tick_nohz_task_switch(void); 275extern void __init tick_nohz_full_setup(cpumask_var_t cpumask); 276#else 277static inline bool tick_nohz_full_enabled(void) { return false; } 278static inline bool tick_nohz_full_cpu(int cpu) { return false; } 279static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { } 280 281static inline void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit) { } 282static inline void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { } 283 284static inline void tick_dep_set(enum tick_dep_bits bit) { } 285static inline void tick_dep_clear(enum tick_dep_bits bit) { } 286static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { } 287static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { } 288static inline void tick_dep_set_task(struct task_struct *tsk, 289 enum tick_dep_bits bit) { } 290static inline void tick_dep_clear_task(struct task_struct *tsk, 291 enum tick_dep_bits bit) { } 292static inline void tick_dep_set_signal(struct task_struct *tsk, 293 enum tick_dep_bits bit) { } 294static inline void tick_dep_clear_signal(struct signal_struct *signal, 295 enum tick_dep_bits bit) { } 296 297static inline void tick_nohz_full_kick_cpu(int cpu) { } 298static inline void __tick_nohz_task_switch(void) { } 299static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { } 300#endif 301 302static inline void tick_nohz_task_switch(void) 303{ 304 if (tick_nohz_full_enabled()) 305 __tick_nohz_task_switch(); 306} 307 308static inline void tick_nohz_user_enter_prepare(void) 309{ 310 if (tick_nohz_full_cpu(smp_processor_id())) 311 rcu_nocb_flush_deferred_wakeup(); 312} 313 314#endif