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 enum tick_dep_bits {
 101         TICK_DEP_BIT_POSIX_TIMER        = 0,
 102         TICK_DEP_BIT_PERF_EVENTS        = 1,
 103         TICK_DEP_BIT_SCHED              = 2,
 104         TICK_DEP_BIT_CLOCK_UNSTABLE     = 3
 105 };
 106
 107 #define TICK_DEP_MASK_NONE              0
 108 #define TICK_DEP_MASK_POSIX_TIMER       (1 << TICK_DEP_BIT_POSIX_TIMER)
 109 #define TICK_DEP_MASK_PERF_EVENTS       (1 << TICK_DEP_BIT_PERF_EVENTS)
 110 #define TICK_DEP_MASK_SCHED             (1 << TICK_DEP_BIT_SCHED)
 111 #define TICK_DEP_MASK_CLOCK_UNSTABLE    (1 << TICK_DEP_BIT_CLOCK_UNSTABLE)
 112
 113 #ifdef CONFIG_NO_HZ_COMMON
 114 extern bool tick_nohz_enabled;
 115 extern int tick_nohz_tick_stopped(void);
 116 extern void tick_nohz_idle_enter(void);
 117 extern void tick_nohz_idle_exit(void);
 118 extern void tick_nohz_irq_exit(void);
 119 extern ktime_t tick_nohz_get_sleep_length(void);
 120 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time);
 121 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time);
 122 #else /* !CONFIG_NO_HZ_COMMON */
 123 #define tick_nohz_enabled (0)
 124 static inline int tick_nohz_tick_stopped(void) { return 0; }
 125 static inline void tick_nohz_idle_enter(void) { }
 126 static inline void tick_nohz_idle_exit(void) { }
 127
 128 static inline ktime_t tick_nohz_get_sleep_length(void)
 129 {
 130         ktime_t len = { .tv64 = NSEC_PER_SEC/HZ };
 131
 132         return len;
 133 }
 134 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; }
 135 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; }
 136 #endif /* !CONFIG_NO_HZ_COMMON */
 137
 138 #ifdef CONFIG_NO_HZ_FULL
 139 extern bool tick_nohz_full_running;
 140 extern cpumask_var_t tick_nohz_full_mask;
 141 extern cpumask_var_t housekeeping_mask;
 142
 143 static inline bool tick_nohz_full_enabled(void)
 144 {
 145         if (!context_tracking_is_enabled())
 146                 return false;
 147
 148         return tick_nohz_full_running;
 149 }
 150
 151 static inline bool tick_nohz_full_cpu(int cpu)
 152 {
 153         if (!tick_nohz_full_enabled())
 154                 return false;
 155
 156         return cpumask_test_cpu(cpu, tick_nohz_full_mask);
 157 }
 158
 159 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask)
 160 {
 161         if (tick_nohz_full_enabled())
 162                 cpumask_or(mask, mask, tick_nohz_full_mask);
 163 }
 164
 165 static inline int housekeeping_any_cpu(void)
 166 {
 167         return cpumask_any_and(housekeeping_mask, cpu_online_mask);
 168 }
 169
 170 extern void tick_nohz_dep_set(enum tick_dep_bits bit);
 171 extern void tick_nohz_dep_clear(enum tick_dep_bits bit);
 172 extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit);
 173 extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit);
 174 extern void tick_nohz_dep_set_task(struct task_struct *tsk,
 175                                    enum tick_dep_bits bit);
 176 extern void tick_nohz_dep_clear_task(struct task_struct *tsk,
 177                                      enum tick_dep_bits bit);
 178 extern void tick_nohz_dep_set_signal(struct signal_struct *signal,
 179                                      enum tick_dep_bits bit);
 180 extern void tick_nohz_dep_clear_signal(struct signal_struct *signal,
 181                                        enum tick_dep_bits bit);
 182
 183 /*
 184  * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases
 185  * on top of static keys.
 186  */
 187 static inline void tick_dep_set(enum tick_dep_bits bit)
 188 {
 189         if (tick_nohz_full_enabled())
 190                 tick_nohz_dep_set(bit);
 191 }
 192
 193 static inline void tick_dep_clear(enum tick_dep_bits bit)
 194 {
 195         if (tick_nohz_full_enabled())
 196                 tick_nohz_dep_clear(bit);
 197 }
 198
 199 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit)
 200 {
 201         if (tick_nohz_full_cpu(cpu))
 202                 tick_nohz_dep_set_cpu(cpu, bit);
 203 }
 204
 205 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit)
 206 {
 207         if (tick_nohz_full_cpu(cpu))
 208                 tick_nohz_dep_clear_cpu(cpu, bit);
 209 }
 210
 211 static inline void tick_dep_set_task(struct task_struct *tsk,
 212                                      enum tick_dep_bits bit)
 213 {
 214         if (tick_nohz_full_enabled())
 215                 tick_nohz_dep_set_task(tsk, bit);
 216 }
 217 static inline void tick_dep_clear_task(struct task_struct *tsk,
 218                                        enum tick_dep_bits bit)
 219 {
 220         if (tick_nohz_full_enabled())
 221                 tick_nohz_dep_clear_task(tsk, bit);
 222 }
 223 static inline void tick_dep_set_signal(struct signal_struct *signal,
 224                                        enum tick_dep_bits bit)
 225 {
 226         if (tick_nohz_full_enabled())
 227                 tick_nohz_dep_set_signal(signal, bit);
 228 }
 229 static inline void tick_dep_clear_signal(struct signal_struct *signal,
 230                                          enum tick_dep_bits bit)
 231 {
 232         if (tick_nohz_full_enabled())
 233                 tick_nohz_dep_clear_signal(signal, bit);
 234 }
 235
 236 extern void tick_nohz_full_kick_cpu(int cpu);
 237 extern void __tick_nohz_task_switch(void);
 238 #else
 239 static inline int housekeeping_any_cpu(void)
 240 {
 241         return smp_processor_id();
 242 }
 243 static inline bool tick_nohz_full_enabled(void) { return false; }
 244 static inline bool tick_nohz_full_cpu(int cpu) { return false; }
 245 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { }
 246
 247 static inline void tick_dep_set(enum tick_dep_bits bit) { }
 248 static inline void tick_dep_clear(enum tick_dep_bits bit) { }
 249 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { }
 250 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { }
 251 static inline void tick_dep_set_task(struct task_struct *tsk,
 252                                      enum tick_dep_bits bit) { }
 253 static inline void tick_dep_clear_task(struct task_struct *tsk,
 254                                        enum tick_dep_bits bit) { }
 255 static inline void tick_dep_set_signal(struct signal_struct *signal,
 256                                        enum tick_dep_bits bit) { }
 257 static inline void tick_dep_clear_signal(struct signal_struct *signal,
 258                                          enum tick_dep_bits bit) { }
 259
 260 static inline void tick_nohz_full_kick_cpu(int cpu) { }
 261 static inline void __tick_nohz_task_switch(void) { }
 262 #endif
 263
 264 static inline const struct cpumask *housekeeping_cpumask(void)
 265 {
 266 #ifdef CONFIG_NO_HZ_FULL
 267         if (tick_nohz_full_enabled())
 268                 return housekeeping_mask;
 269 #endif
 270         return cpu_possible_mask;
 271 }
 272
 273 static inline bool is_housekeeping_cpu(int cpu)
 274 {
 275 #ifdef CONFIG_NO_HZ_FULL
 276         if (tick_nohz_full_enabled())
 277                 return cpumask_test_cpu(cpu, housekeeping_mask);
 278 #endif
 279         return true;
 280 }
 281
 282 static inline void housekeeping_affine(struct task_struct *t)
 283 {
 284 #ifdef CONFIG_NO_HZ_FULL
 285         if (tick_nohz_full_enabled())
 286                 set_cpus_allowed_ptr(t, housekeeping_mask);
 287
 288 #endif
 289 }
 290
 291 static inline void tick_nohz_task_switch(void)
 292 {
 293         if (tick_nohz_full_enabled())
 294                 __tick_nohz_task_switch();
 295 }
 296
 297 #endif