include/linux/tick.h

   1 /*
   2  * Tick related global functions
   3  */
   4 #ifndef _LINUX_TICK_H
   5 #define _LINUX_TICK_H
   6
   7 #include <linux/clockchips.h>
   8 #include <linux/irqflags.h>
   9 #include <linux/percpu.h>
  10 #include <linux/context_tracking_state.h>
  11 #include <linux/cpumask.h>
  12 #include <linux/sched.h>
  13
  14 #ifdef CONFIG_GENERIC_CLOCKEVENTS
  15 extern void __init tick_init(void);
  16 /* Should be core only, but ARM BL switcher requires it */
  17 extern void tick_suspend_local(void);
  18 /* Should be core only, but XEN resume magic and ARM BL switcher require it */
  19 extern void tick_resume_local(void);
  20 extern void tick_handover_do_timer(void);
  21 extern void tick_cleanup_dead_cpu(int cpu);
  22 #else /* CONFIG_GENERIC_CLOCKEVENTS */
  23 static inline void tick_init(void) { }
  24 static inline void tick_suspend_local(void) { }
  25 static inline void tick_resume_local(void) { }
  26 static inline void tick_handover_do_timer(void) { }
  27 static inline void tick_cleanup_dead_cpu(int cpu) { }
  28 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */
  29
  30 #if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_SUSPEND)
  31 extern void tick_freeze(void);
  32 extern void tick_unfreeze(void);
  33 #else
  34 static inline void tick_freeze(void) { }
  35 static inline void tick_unfreeze(void) { }
  36 #endif
  37
  38 #ifdef CONFIG_TICK_ONESHOT
  39 extern void tick_irq_enter(void);
  40 #  ifndef arch_needs_cpu
  41 #   define arch_needs_cpu() (0)
  42 #  endif
  43 # else
  44 static inline void tick_irq_enter(void) { }
  45 #endif
  46
  47 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
  48 extern void hotplug_cpu__broadcast_tick_pull(int dead_cpu);
  49 #else
  50 static inline void hotplug_cpu__broadcast_tick_pull(int dead_cpu) { }
  51 #endif
  52
  53 enum tick_broadcast_mode {
  54         TICK_BROADCAST_OFF,
  55         TICK_BROADCAST_ON,
  56         TICK_BROADCAST_FORCE,
  57 };
  58
  59 enum tick_broadcast_state {
  60         TICK_BROADCAST_EXIT,
  61         TICK_BROADCAST_ENTER,
  62 };
  63
  64 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
  65 extern void tick_broadcast_control(enum tick_broadcast_mode mode);
  66 #else
  67 static inline void tick_broadcast_control(enum tick_broadcast_mode mode) { }
  68 #endif /* BROADCAST */
  69
  70 #ifdef CONFIG_GENERIC_CLOCKEVENTS
  71 extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state);
  72 #else
  73 static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state)
  74 {
  75         return 0;
  76 }
  77 #endif
  78
  79 static inline void tick_broadcast_enable(void)
  80 {
  81         tick_broadcast_control(TICK_BROADCAST_ON);
  82 }
  83 static inline void tick_broadcast_disable(void)
  84 {
  85         tick_broadcast_control(TICK_BROADCAST_OFF);
  86 }
  87 static inline void tick_broadcast_force(void)
  88 {
  89         tick_broadcast_control(TICK_BROADCAST_FORCE);
  90 }
  91 static inline int tick_broadcast_enter(void)
  92 {
  93         return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER);
  94 }
  95 static inline void tick_broadcast_exit(void)
  96 {
  97         tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT);
  98 }
  99
 100 #ifdef CONFIG_NO_HZ_COMMON
 101 extern int tick_nohz_enabled;
 102 extern int tick_nohz_tick_stopped(void);
 103 extern void tick_nohz_idle_enter(void);
 104 extern void tick_nohz_idle_exit(void);
 105 extern void tick_nohz_irq_exit(void);
 106 extern ktime_t tick_nohz_get_sleep_length(void);
 107 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
 108 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
 109 #else /* !CONFIG_NO_HZ_COMMON */
 110 #define tick_nohz_enabled (0)
 111 static inline int tick_nohz_tick_stopped(void) { return 0; }
 112 static inline void tick_nohz_idle_enter(void) { }
 113 static inline void tick_nohz_idle_exit(void) { }
 114
 115 static inline ktime_t tick_nohz_get_sleep_length(void)
 116 {
 117         ktime_t len = { .tv64 = NSEC_PER_SEC/HZ };
 118
 119         return len;
 120 }
 121 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
 122 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
 123 #endif /* !CONFIG_NO_HZ_COMMON */
 124
 125 #ifdef CONFIG_NO_HZ_FULL
 126 extern bool tick_nohz_full_running;
 127 extern cpumask_var_t tick_nohz_full_mask;
 128 extern cpumask_var_t housekeeping_mask;
 129
 130 static inline bool tick_nohz_full_enabled(void)
 131 {
 132         if (!context_tracking_is_enabled())
 133                 return false;
 134
 135         return tick_nohz_full_running;
 136 }
 137
 138 static inline bool tick_nohz_full_cpu(int cpu)
 139 {
 140         if (!tick_nohz_full_enabled())
 141                 return false;
 142
 143         return cpumask_test_cpu(cpu, tick_nohz_full_mask);
 144 }
 145
 146 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
 147 {
 148         if (tick_nohz_full_enabled())
 149                 cpumask_or(mask, mask, tick_nohz_full_mask);
 150 }
 151
 152 static inline int housekeeping_any_cpu(void)
 153 {
 154         return cpumask_any_and(housekeeping_mask, cpu_online_mask);
 155 }
 156
 157 extern void tick_nohz_full_kick(void);
 158 extern void tick_nohz_full_kick_cpu(int cpu);
 159 extern void tick_nohz_full_kick_all(void);
 160 extern void __tick_nohz_task_switch(void);
 161 #else
 162 static inline int housekeeping_any_cpu(void)
 163 {
 164         return smp_processor_id();
 165 }
 166 static inline bool tick_nohz_full_enabled(void) { return false; }
 167 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
 168 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
 169 static inline void tick_nohz_full_kick_cpu(int cpu) { }
 170 static inline void tick_nohz_full_kick(void) { }
 171 static inline void tick_nohz_full_kick_all(void) { }
 172 static inline void __tick_nohz_task_switch(void) { }
 173 #endif
 174
 175 static inline const struct cpumask *housekeeping_cpumask(void)
 176 {
 177 #ifdef CONFIG_NO_HZ_FULL
 178         if (tick_nohz_full_enabled())
 179                 return housekeeping_mask;
 180 #endif
 181         return cpu_possible_mask;
 182 }
 183
 184 static inline bool is_housekeeping_cpu(int cpu)
 185 {
 186 #ifdef CONFIG_NO_HZ_FULL
 187         if (tick_nohz_full_enabled())
 188                 return cpumask_test_cpu(cpu, housekeeping_mask);
 189 #endif
 190         return true;
 191 }
 192
 193 static inline void housekeeping_affine(struct task_struct *t)
 194 {
 195 #ifdef CONFIG_NO_HZ_FULL
 196         if (tick_nohz_full_enabled())
 197                 set_cpus_allowed_ptr(t, housekeeping_mask);
 198
 199 #endif
 200 }
 201
 202 static inline void tick_nohz_task_switch(void)
 203 {
 204         if (tick_nohz_full_enabled())
 205                 __tick_nohz_task_switch();
 206 }
 207
 208 #endif