linux/include/linux/tick.h
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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
  15#ifdef CONFIG_GENERIC_CLOCKEVENTS
  16extern void __init tick_init(void);
  17/* Should be core only, but ARM BL switcher requires it */
  18extern void tick_suspend_local(void);
  19/* Should be core only, but XEN resume magic and ARM BL switcher require it */
  20extern void tick_resume_local(void);
  21extern void tick_handover_do_timer(void);
  22extern void tick_cleanup_dead_cpu(int cpu);
  23#else /* CONFIG_GENERIC_CLOCKEVENTS */
  24static inline void tick_init(void) { }
  25static inline void tick_suspend_local(void) { }
  26static inline void tick_resume_local(void) { }
  27static inline void tick_handover_do_timer(void) { }
  28static inline void tick_cleanup_dead_cpu(int cpu) { }
  29#endif /* !CONFIG_GENERIC_CLOCKEVENTS */
  30
  31#if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_SUSPEND)
  32extern void tick_freeze(void);
  33extern void tick_unfreeze(void);
  34#else
  35static inline void tick_freeze(void) { }
  36static inline void tick_unfreeze(void) { }
  37#endif
  38
  39#ifdef CONFIG_TICK_ONESHOT
  40extern void tick_irq_enter(void);
  41#  ifndef arch_needs_cpu
  42#   define arch_needs_cpu() (0)
  43#  endif
  44# else
  45static inline void tick_irq_enter(void) { }
  46#endif
  47
  48#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
  49extern void hotplug_cpu__broadcast_tick_pull(int dead_cpu);
  50#else
  51static inline void hotplug_cpu__broadcast_tick_pull(int dead_cpu) { }
  52#endif
  53
  54enum tick_broadcast_mode {
  55        TICK_BROADCAST_OFF,
  56        TICK_BROADCAST_ON,
  57        TICK_BROADCAST_FORCE,
  58};
  59
  60enum tick_broadcast_state {
  61        TICK_BROADCAST_EXIT,
  62        TICK_BROADCAST_ENTER,
  63};
  64
  65#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
  66extern void tick_broadcast_control(enum tick_broadcast_mode mode);
  67#else
  68static inline void tick_broadcast_control(enum tick_broadcast_mode mode) { }
  69#endif /* BROADCAST */
  70
  71#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_HOTPLUG_CPU)
  72extern void tick_offline_cpu(unsigned int cpu);
  73#else
  74static inline void tick_offline_cpu(unsigned int cpu) { }
  75#endif
  76
  77#ifdef CONFIG_GENERIC_CLOCKEVENTS
  78extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state);
  79#else
  80static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state)
  81{
  82        return 0;
  83}
  84#endif
  85
  86static inline void tick_broadcast_enable(void)
  87{
  88        tick_broadcast_control(TICK_BROADCAST_ON);
  89}
  90static inline void tick_broadcast_disable(void)
  91{
  92        tick_broadcast_control(TICK_BROADCAST_OFF);
  93}
  94static inline void tick_broadcast_force(void)
  95{
  96        tick_broadcast_control(TICK_BROADCAST_FORCE);
  97}
  98static inline int tick_broadcast_enter(void)
  99{
 100        return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER);
 101}
 102static inline void tick_broadcast_exit(void)
 103{
 104        tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT);
 105}
 106
 107enum tick_dep_bits {
 108        TICK_DEP_BIT_POSIX_TIMER        = 0,
 109        TICK_DEP_BIT_PERF_EVENTS        = 1,
 110        TICK_DEP_BIT_SCHED              = 2,
 111        TICK_DEP_BIT_CLOCK_UNSTABLE     = 3
 112};
 113
 114#define TICK_DEP_MASK_NONE              0
 115#define TICK_DEP_MASK_POSIX_TIMER       (1 << TICK_DEP_BIT_POSIX_TIMER)
 116#define TICK_DEP_MASK_PERF_EVENTS       (1 << TICK_DEP_BIT_PERF_EVENTS)
 117#define TICK_DEP_MASK_SCHED             (1 << TICK_DEP_BIT_SCHED)
 118#define TICK_DEP_MASK_CLOCK_UNSTABLE    (1 << TICK_DEP_BIT_CLOCK_UNSTABLE)
 119
 120#ifdef CONFIG_NO_HZ_COMMON
 121extern bool tick_nohz_enabled;
 122extern bool tick_nohz_tick_stopped(void);
 123extern bool tick_nohz_tick_stopped_cpu(int cpu);
 124extern void tick_nohz_idle_stop_tick(void);
 125extern void tick_nohz_idle_retain_tick(void);
 126extern void tick_nohz_idle_restart_tick(void);
 127extern void tick_nohz_idle_enter(void);
 128extern void tick_nohz_idle_exit(void);
 129extern void tick_nohz_irq_exit(void);
 130extern bool tick_nohz_idle_got_tick(void);
 131extern ktime_t tick_nohz_get_next_hrtimer(void);
 132extern ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next);
 133extern unsigned long tick_nohz_get_idle_calls(void);
 134extern unsigned long tick_nohz_get_idle_calls_cpu(int cpu);
 135extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
 136extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
 137
 138static inline void tick_nohz_idle_stop_tick_protected(void)
 139{
 140        local_irq_disable();
 141        tick_nohz_idle_stop_tick();
 142        local_irq_enable();
 143}
 144
 145#else /* !CONFIG_NO_HZ_COMMON */
 146#define tick_nohz_enabled (0)
 147static inline int tick_nohz_tick_stopped(void) { return 0; }
 148static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; }
 149static inline void tick_nohz_idle_stop_tick(void) { }
 150static inline void tick_nohz_idle_retain_tick(void) { }
 151static inline void tick_nohz_idle_restart_tick(void) { }
 152static inline void tick_nohz_idle_enter(void) { }
 153static inline void tick_nohz_idle_exit(void) { }
 154static inline bool tick_nohz_idle_got_tick(void) { return false; }
 155static inline ktime_t tick_nohz_get_next_hrtimer(void)
 156{
 157        /* Next wake up is the tick period, assume it starts now */
 158        return ktime_add(ktime_get(), TICK_NSEC);
 159}
 160static inline ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next)
 161{
 162        *delta_next = TICK_NSEC;
 163        return *delta_next;
 164}
 165static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
 166static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
 167
 168static inline void tick_nohz_idle_stop_tick_protected(void) { }
 169#endif /* !CONFIG_NO_HZ_COMMON */
 170
 171#ifdef CONFIG_NO_HZ_FULL
 172extern bool tick_nohz_full_running;
 173extern cpumask_var_t tick_nohz_full_mask;
 174
 175static inline bool tick_nohz_full_enabled(void)
 176{
 177        if (!context_tracking_is_enabled())
 178                return false;
 179
 180        return tick_nohz_full_running;
 181}
 182
 183static inline bool tick_nohz_full_cpu(int cpu)
 184{
 185        if (!tick_nohz_full_enabled())
 186                return false;
 187
 188        return cpumask_test_cpu(cpu, tick_nohz_full_mask);
 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 signal_struct *signal,
 206                                     enum tick_dep_bits bit);
 207extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
 208                                       enum tick_dep_bits bit);
 209
 210/*
 211 * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
 212 * on top of static keys.
 213 */
 214static inline void tick_dep_set(enum tick_dep_bits bit)
 215{
 216        if (tick_nohz_full_enabled())
 217                tick_nohz_dep_set(bit);
 218}
 219
 220static inline void tick_dep_clear(enum tick_dep_bits bit)
 221{
 222        if (tick_nohz_full_enabled())
 223                tick_nohz_dep_clear(bit);
 224}
 225
 226static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
 227{
 228        if (tick_nohz_full_cpu(cpu))
 229                tick_nohz_dep_set_cpu(cpu, bit);
 230}
 231
 232static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
 233{
 234        if (tick_nohz_full_cpu(cpu))
 235                tick_nohz_dep_clear_cpu(cpu, bit);
 236}
 237
 238static inline void tick_dep_set_task(struct task_struct *tsk,
 239                                     enum tick_dep_bits bit)
 240{
 241        if (tick_nohz_full_enabled())
 242                tick_nohz_dep_set_task(tsk, bit);
 243}
 244static inline void tick_dep_clear_task(struct task_struct *tsk,
 245                                       enum tick_dep_bits bit)
 246{
 247        if (tick_nohz_full_enabled())
 248                tick_nohz_dep_clear_task(tsk, bit);
 249}
 250static inline void tick_dep_set_signal(struct signal_struct *signal,
 251                                       enum tick_dep_bits bit)
 252{
 253        if (tick_nohz_full_enabled())
 254                tick_nohz_dep_set_signal(signal, bit);
 255}
 256static inline void tick_dep_clear_signal(struct signal_struct *signal,
 257                                         enum tick_dep_bits bit)
 258{
 259        if (tick_nohz_full_enabled())
 260                tick_nohz_dep_clear_signal(signal, bit);
 261}
 262
 263extern void tick_nohz_full_kick_cpu(int cpu);
 264extern void __tick_nohz_task_switch(void);
 265extern void __init tick_nohz_full_setup(cpumask_var_t cpumask);
 266#else
 267static inline bool tick_nohz_full_enabled(void) { return false; }
 268static inline bool tick_nohz_full_cpu(int cpu) { return false; }
 269static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
 270
 271static inline void tick_dep_set(enum tick_dep_bits bit) { }
 272static inline void tick_dep_clear(enum tick_dep_bits bit) { }
 273static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
 274static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
 275static inline void tick_dep_set_task(struct task_struct *tsk,
 276                                     enum tick_dep_bits bit) { }
 277static inline void tick_dep_clear_task(struct task_struct *tsk,
 278                                       enum tick_dep_bits bit) { }
 279static inline void tick_dep_set_signal(struct signal_struct *signal,
 280                                       enum tick_dep_bits bit) { }
 281static inline void tick_dep_clear_signal(struct signal_struct *signal,
 282                                         enum tick_dep_bits bit) { }
 283
 284static inline void tick_nohz_full_kick_cpu(int cpu) { }
 285static inline void __tick_nohz_task_switch(void) { }
 286static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { }
 287#endif
 288
 289static inline void tick_nohz_task_switch(void)
 290{
 291        if (tick_nohz_full_enabled())
 292                __tick_nohz_task_switch();
 293}
 294
 295#endif
 296