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#ifdef CONFIG_GENERIC_CLOCKEVENTS
  72extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state);
  73#else
  74static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state)
  75{
  76        return 0;
  77}
  78#endif
  79
  80static inline void tick_broadcast_enable(void)
  81{
  82        tick_broadcast_control(TICK_BROADCAST_ON);
  83}
  84static inline void tick_broadcast_disable(void)
  85{
  86        tick_broadcast_control(TICK_BROADCAST_OFF);
  87}
  88static inline void tick_broadcast_force(void)
  89{
  90        tick_broadcast_control(TICK_BROADCAST_FORCE);
  91}
  92static inline int tick_broadcast_enter(void)
  93{
  94        return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER);
  95}
  96static inline void tick_broadcast_exit(void)
  97{
  98        tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT);
  99}
 100
 101enum tick_dep_bits {
 102        TICK_DEP_BIT_POSIX_TIMER        = 0,
 103        TICK_DEP_BIT_PERF_EVENTS        = 1,
 104        TICK_DEP_BIT_SCHED              = 2,
 105        TICK_DEP_BIT_CLOCK_UNSTABLE     = 3
 106};
 107
 108#define TICK_DEP_MASK_NONE              0
 109#define TICK_DEP_MASK_POSIX_TIMER       (1 << TICK_DEP_BIT_POSIX_TIMER)
 110#define TICK_DEP_MASK_PERF_EVENTS       (1 << TICK_DEP_BIT_PERF_EVENTS)
 111#define TICK_DEP_MASK_SCHED             (1 << TICK_DEP_BIT_SCHED)
 112#define TICK_DEP_MASK_CLOCK_UNSTABLE    (1 << TICK_DEP_BIT_CLOCK_UNSTABLE)
 113
 114#ifdef CONFIG_NO_HZ_COMMON
 115extern bool tick_nohz_enabled;
 116extern bool tick_nohz_tick_stopped(void);
 117extern bool tick_nohz_tick_stopped_cpu(int cpu);
 118extern void tick_nohz_idle_stop_tick(void);
 119extern void tick_nohz_idle_retain_tick(void);
 120extern void tick_nohz_idle_restart_tick(void);
 121extern void tick_nohz_idle_enter(void);
 122extern void tick_nohz_idle_exit(void);
 123extern void tick_nohz_irq_exit(void);
 124extern bool tick_nohz_idle_got_tick(void);
 125extern ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next);
 126extern unsigned long tick_nohz_get_idle_calls(void);
 127extern unsigned long tick_nohz_get_idle_calls_cpu(int cpu);
 128extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
 129extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
 130
 131static inline void tick_nohz_idle_stop_tick_protected(void)
 132{
 133        local_irq_disable();
 134        tick_nohz_idle_stop_tick();
 135        local_irq_enable();
 136}
 137
 138#else /* !CONFIG_NO_HZ_COMMON */
 139#define tick_nohz_enabled (0)
 140static inline int tick_nohz_tick_stopped(void) { return 0; }
 141static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; }
 142static inline void tick_nohz_idle_stop_tick(void) { }
 143static inline void tick_nohz_idle_retain_tick(void) { }
 144static inline void tick_nohz_idle_restart_tick(void) { }
 145static inline void tick_nohz_idle_enter(void) { }
 146static inline void tick_nohz_idle_exit(void) { }
 147static inline bool tick_nohz_idle_got_tick(void) { return false; }
 148
 149static inline ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next)
 150{
 151        *delta_next = TICK_NSEC;
 152        return *delta_next;
 153}
 154static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
 155static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
 156
 157static inline void tick_nohz_idle_stop_tick_protected(void) { }
 158#endif /* !CONFIG_NO_HZ_COMMON */
 159
 160#ifdef CONFIG_NO_HZ_FULL
 161extern bool tick_nohz_full_running;
 162extern cpumask_var_t tick_nohz_full_mask;
 163
 164static inline bool tick_nohz_full_enabled(void)
 165{
 166        if (!context_tracking_is_enabled())
 167                return false;
 168
 169        return tick_nohz_full_running;
 170}
 171
 172static inline bool tick_nohz_full_cpu(int cpu)
 173{
 174        if (!tick_nohz_full_enabled())
 175                return false;
 176
 177        return cpumask_test_cpu(cpu, tick_nohz_full_mask);
 178}
 179
 180static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
 181{
 182        if (tick_nohz_full_enabled())
 183                cpumask_or(mask, mask, tick_nohz_full_mask);
 184}
 185
 186extern void tick_nohz_dep_set(enum tick_dep_bits bit);
 187extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
 188extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
 189extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
 190extern void tick_nohz_dep_set_task(struct task_struct *tsk,
 191                                   enum tick_dep_bits bit);
 192extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
 193                                     enum tick_dep_bits bit);
 194extern void tick_nohz_dep_set_signal(struct signal_struct *signal,
 195                                     enum tick_dep_bits bit);
 196extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
 197                                       enum tick_dep_bits bit);
 198
 199/*
 200 * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
 201 * on top of static keys.
 202 */
 203static inline void tick_dep_set(enum tick_dep_bits bit)
 204{
 205        if (tick_nohz_full_enabled())
 206                tick_nohz_dep_set(bit);
 207}
 208
 209static inline void tick_dep_clear(enum tick_dep_bits bit)
 210{
 211        if (tick_nohz_full_enabled())
 212                tick_nohz_dep_clear(bit);
 213}
 214
 215static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
 216{
 217        if (tick_nohz_full_cpu(cpu))
 218                tick_nohz_dep_set_cpu(cpu, bit);
 219}
 220
 221static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
 222{
 223        if (tick_nohz_full_cpu(cpu))
 224                tick_nohz_dep_clear_cpu(cpu, bit);
 225}
 226
 227static inline void tick_dep_set_task(struct task_struct *tsk,
 228                                     enum tick_dep_bits bit)
 229{
 230        if (tick_nohz_full_enabled())
 231                tick_nohz_dep_set_task(tsk, bit);
 232}
 233static inline void tick_dep_clear_task(struct task_struct *tsk,
 234                                       enum tick_dep_bits bit)
 235{
 236        if (tick_nohz_full_enabled())
 237                tick_nohz_dep_clear_task(tsk, bit);
 238}
 239static inline void tick_dep_set_signal(struct signal_struct *signal,
 240                                       enum tick_dep_bits bit)
 241{
 242        if (tick_nohz_full_enabled())
 243                tick_nohz_dep_set_signal(signal, bit);
 244}
 245static inline void tick_dep_clear_signal(struct signal_struct *signal,
 246                                         enum tick_dep_bits bit)
 247{
 248        if (tick_nohz_full_enabled())
 249                tick_nohz_dep_clear_signal(signal, bit);
 250}
 251
 252extern void tick_nohz_full_kick_cpu(int cpu);
 253extern void __tick_nohz_task_switch(void);
 254extern void __init tick_nohz_full_setup(cpumask_var_t cpumask);
 255#else
 256static inline bool tick_nohz_full_enabled(void) { return false; }
 257static inline bool tick_nohz_full_cpu(int cpu) { return false; }
 258static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
 259
 260static inline void tick_dep_set(enum tick_dep_bits bit) { }
 261static inline void tick_dep_clear(enum tick_dep_bits bit) { }
 262static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
 263static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
 264static inline void tick_dep_set_task(struct task_struct *tsk,
 265                                     enum tick_dep_bits bit) { }
 266static inline void tick_dep_clear_task(struct task_struct *tsk,
 267                                       enum tick_dep_bits bit) { }
 268static inline void tick_dep_set_signal(struct signal_struct *signal,
 269                                       enum tick_dep_bits bit) { }
 270static inline void tick_dep_clear_signal(struct signal_struct *signal,
 271                                         enum tick_dep_bits bit) { }
 272
 273static inline void tick_nohz_full_kick_cpu(int cpu) { }
 274static inline void __tick_nohz_task_switch(void) { }
 275static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { }
 276#endif
 277
 278static inline void tick_nohz_task_switch(void)
 279{
 280        if (tick_nohz_full_enabled())
 281                __tick_nohz_task_switch();
 282}
 283
 284#endif
 285