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 17 extern void __init tick_init(void); 18 /* Should be core only, but ARM BL switcher requires it */ 19 extern void tick_suspend_local(void); 20 /* Should be core only, but XEN resume magic and ARM BL switcher require it */ 21 extern void tick_resume_local(void); 22 extern void tick_handover_do_timer(void); 23 extern void tick_cleanup_dead_cpu(int cpu); 24 #else /* CONFIG_GENERIC_CLOCKEVENTS */ 25 static inline void tick_init(void) { } 26 static inline void tick_suspend_local(void) { } 27 static inline void tick_resume_local(void) { } 28 static inline void tick_handover_do_timer(void) { } 29 static inline void tick_cleanup_dead_cpu(int cpu) { } 30 #endif /* !CONFIG_GENERIC_CLOCKEVENTS */ 31 32 #if defined(CONFIG_GENERIC_CLOCKEVENTS) && defined(CONFIG_SUSPEND) 33 extern void tick_freeze(void); 34 extern void tick_unfreeze(void); 35 #else 36 static inline void tick_freeze(void) { } 37 static inline void tick_unfreeze(void) { } 38 #endif 39 40 #ifdef CONFIG_TICK_ONESHOT 41 extern void tick_irq_enter(void); 42 # ifndef arch_needs_cpu 43 # define arch_needs_cpu() (0) 44 # endif 45 # else 46 static inline void tick_irq_enter(void) { } 47 #endif 48 49 #if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT) 50 extern void hotplug_cpu__broadcast_tick_pull(int dead_cpu); 51 #else 52 static inline void hotplug_cpu__broadcast_tick_pull(int dead_cpu) { } 53 #endif 54 55 enum tick_broadcast_mode { 56 TICK_BROADCAST_OFF, 57 TICK_BROADCAST_ON, 58 TICK_BROADCAST_FORCE, 59 }; 60 61 enum tick_broadcast_state { 62 TICK_BROADCAST_EXIT, 63 TICK_BROADCAST_ENTER, 64 }; 65 66 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST 67 extern void tick_broadcast_control(enum tick_broadcast_mode mode); 68 #else 69 static 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) 73 extern void tick_offline_cpu(unsigned int cpu); 74 #else 75 static inline void tick_offline_cpu(unsigned int cpu) { } 76 #endif 77 78 #ifdef CONFIG_GENERIC_CLOCKEVENTS 79 extern int tick_broadcast_oneshot_control(enum tick_broadcast_state state); 80 #else 81 static inline int tick_broadcast_oneshot_control(enum tick_broadcast_state state) 82 { 83 return 0; 84 } 85 #endif 86 87 static inline void tick_broadcast_enable(void) 88 { 89 tick_broadcast_control(TICK_BROADCAST_ON); 90 } 91 static inline void tick_broadcast_disable(void) 92 { 93 tick_broadcast_control(TICK_BROADCAST_OFF); 94 } 95 static inline void tick_broadcast_force(void) 96 { 97 tick_broadcast_control(TICK_BROADCAST_FORCE); 98 } 99 static inline int tick_broadcast_enter(void) 100 { 101 return tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER); 102 } 103 static inline void tick_broadcast_exit(void) 104 { 105 tick_broadcast_oneshot_control(TICK_BROADCAST_EXIT); 106 } 107 108 enum 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 127 extern bool tick_nohz_enabled; 128 extern bool tick_nohz_tick_stopped(void); 129 extern bool tick_nohz_tick_stopped_cpu(int cpu); 130 extern void tick_nohz_idle_stop_tick(void); 131 extern void tick_nohz_idle_retain_tick(void); 132 extern void tick_nohz_idle_restart_tick(void); 133 extern void tick_nohz_idle_enter(void); 134 extern void tick_nohz_idle_exit(void); 135 extern void tick_nohz_irq_exit(void); 136 extern bool tick_nohz_idle_got_tick(void); 137 extern ktime_t tick_nohz_get_next_hrtimer(void); 138 extern ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next); 139 extern unsigned long tick_nohz_get_idle_calls(void); 140 extern unsigned long tick_nohz_get_idle_calls_cpu(int cpu); 141 extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time); 142 extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time); 143 144 static 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) 153 static inline int tick_nohz_tick_stopped(void) { return 0; } 154 static inline int tick_nohz_tick_stopped_cpu(int cpu) { return 0; } 155 static inline void tick_nohz_idle_stop_tick(void) { } 156 static inline void tick_nohz_idle_retain_tick(void) { } 157 static inline void tick_nohz_idle_restart_tick(void) { } 158 static inline void tick_nohz_idle_enter(void) { } 159 static inline void tick_nohz_idle_exit(void) { } 160 static inline bool tick_nohz_idle_got_tick(void) { return false; } 161 static 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 } 166 static inline ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next) 167 { 168 *delta_next = TICK_NSEC; 169 return *delta_next; 170 } 171 static inline u64 get_cpu_idle_time_us(int cpu, u64 *unused) { return -1; } 172 static inline u64 get_cpu_iowait_time_us(int cpu, u64 *unused) { return -1; } 173 174 static inline void tick_nohz_idle_stop_tick_protected(void) { } 175 #endif /* !CONFIG_NO_HZ_COMMON */ 176 177 #ifdef CONFIG_NO_HZ_FULL 178 extern bool tick_nohz_full_running; 179 extern cpumask_var_t tick_nohz_full_mask; 180 181 static 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 }) 200 201 static 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 } 206 207 extern void tick_nohz_dep_set(enum tick_dep_bits bit); 208 extern void tick_nohz_dep_clear(enum tick_dep_bits bit); 209 extern void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit); 210 extern void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit); 211 extern void tick_nohz_dep_set_task(struct task_struct *tsk, 212 enum tick_dep_bits bit); 213 extern void tick_nohz_dep_clear_task(struct task_struct *tsk, 214 enum tick_dep_bits bit); 215 extern void tick_nohz_dep_set_signal(struct task_struct *tsk, 216 enum tick_dep_bits bit); 217 extern void tick_nohz_dep_clear_signal(struct signal_struct *signal, 218 enum tick_dep_bits bit); 219 extern bool tick_nohz_cpu_hotpluggable(unsigned int cpu); 220 221 /* 222 * The below are tick_nohz_[set,clear]_dep() wrappers that optimize off-cases 223 * on top of static keys. 224 */ 225 static inline void tick_dep_set(enum tick_dep_bits bit) 226 { 227 if (tick_nohz_full_enabled()) 228 tick_nohz_dep_set(bit); 229 } 230 231 static inline void tick_dep_clear(enum tick_dep_bits bit) 232 { 233 if (tick_nohz_full_enabled()) 234 tick_nohz_dep_clear(bit); 235 } 236 237 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) 238 { 239 if (tick_nohz_full_cpu(cpu)) 240 tick_nohz_dep_set_cpu(cpu, bit); 241 } 242 243 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) 244 { 245 if (tick_nohz_full_cpu(cpu)) 246 tick_nohz_dep_clear_cpu(cpu, bit); 247 } 248 249 static inline void tick_dep_set_task(struct task_struct *tsk, 250 enum tick_dep_bits bit) 251 { 252 if (tick_nohz_full_enabled()) 253 tick_nohz_dep_set_task(tsk, bit); 254 } 255 static inline void tick_dep_clear_task(struct task_struct *tsk, 256 enum tick_dep_bits bit) 257 { 258 if (tick_nohz_full_enabled()) 259 tick_nohz_dep_clear_task(tsk, bit); 260 } 261 static inline void tick_dep_set_signal(struct task_struct *tsk, 262 enum tick_dep_bits bit) 263 { 264 if (tick_nohz_full_enabled()) 265 tick_nohz_dep_set_signal(tsk, bit); 266 } 267 static inline void tick_dep_clear_signal(struct signal_struct *signal, 268 enum tick_dep_bits bit) 269 { 270 if (tick_nohz_full_enabled()) 271 tick_nohz_dep_clear_signal(signal, bit); 272 } 273 274 extern void tick_nohz_full_kick_cpu(int cpu); 275 extern void __tick_nohz_task_switch(void); 276 extern void __init tick_nohz_full_setup(cpumask_var_t cpumask); 277 #else 278 static inline bool tick_nohz_full_enabled(void) { return false; } 279 static inline bool tick_nohz_full_cpu(int cpu) { return false; } 280 static inline void tick_nohz_full_add_cpus_to(struct cpumask *mask) { } 281 282 static inline void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit) { } 283 static inline void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { } 284 static inline bool tick_nohz_cpu_hotpluggable(unsigned int cpu) { return true; } 285 286 static inline void tick_dep_set(enum tick_dep_bits bit) { } 287 static inline void tick_dep_clear(enum tick_dep_bits bit) { } 288 static inline void tick_dep_set_cpu(int cpu, enum tick_dep_bits bit) { } 289 static inline void tick_dep_clear_cpu(int cpu, enum tick_dep_bits bit) { } 290 static inline void tick_dep_set_task(struct task_struct *tsk, 291 enum tick_dep_bits bit) { } 292 static inline void tick_dep_clear_task(struct task_struct *tsk, 293 enum tick_dep_bits bit) { } 294 static inline void tick_dep_set_signal(struct task_struct *tsk, 295 enum tick_dep_bits bit) { } 296 static inline void tick_dep_clear_signal(struct signal_struct *signal, 297 enum tick_dep_bits bit) { } 298 299 static inline void tick_nohz_full_kick_cpu(int cpu) { } 300 static inline void __tick_nohz_task_switch(void) { } 301 static inline void tick_nohz_full_setup(cpumask_var_t cpumask) { } 302 #endif 303 304 static inline void tick_nohz_task_switch(void) 305 { 306 if (tick_nohz_full_enabled()) 307 __tick_nohz_task_switch(); 308 } 309 310 static inline void tick_nohz_user_enter_prepare(void) 311 { 312 if (tick_nohz_full_cpu(smp_processor_id())) 313 rcu_nocb_flush_deferred_wakeup(); 314 } 315 316 #endif 317