1 2 #include <linux/sched.h> 3 #include <linux/sched/sysctl.h> 4 #include <linux/sched/rt.h> 5 #include <linux/mutex.h> 6 #include <linux/spinlock.h> 7 #include <linux/stop_machine.h> 8 #include <linux/tick.h> 9 #include <linux/slab.h> 10 11 #include "cpupri.h" 12 #include "cpuacct.h" 13 14 struct rq; 15 16 extern __read_mostly int scheduler_running; 17 18 extern unsigned long calc_load_update; 19 extern atomic_long_t calc_load_tasks; 20 21 extern long calc_load_fold_active(struct rq *this_rq); 22 extern void update_cpu_load_active(struct rq *this_rq); 23 24 /* 25 * Convert user-nice values [ -20 ... 0 ... 19 ] 26 * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ], 27 * and back. 28 */ 29 #define NICE_TO_PRIO(nice) (MAX_RT_PRIO + (nice) + 20) 30 #define PRIO_TO_NICE(prio) ((prio) - MAX_RT_PRIO - 20) 31 #define TASK_NICE(p) PRIO_TO_NICE((p)->static_prio) 32 33 /* 34 * 'User priority' is the nice value converted to something we 35 * can work with better when scaling various scheduler parameters, 36 * it's a [ 0 ... 39 ] range. 37 */ 38 #define USER_PRIO(p) ((p)-MAX_RT_PRIO) 39 #define TASK_USER_PRIO(p) USER_PRIO((p)->static_prio) 40 #define MAX_USER_PRIO (USER_PRIO(MAX_PRIO)) 41 42 /* 43 * Helpers for converting nanosecond timing to jiffy resolution 44 */ 45 #define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ)) 46 47 /* 48 * Increase resolution of nice-level calculations for 64-bit architectures. 49 * The extra resolution improves shares distribution and load balancing of 50 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup 51 * hierarchies, especially on larger systems. This is not a user-visible change 52 * and does not change the user-interface for setting shares/weights. 53 * 54 * We increase resolution only if we have enough bits to allow this increased 55 * resolution (i.e. BITS_PER_LONG > 32). The costs for increasing resolution 56 * when BITS_PER_LONG <= 32 are pretty high and the returns do not justify the 57 * increased costs. 58 */ 59 #if 0 /* BITS_PER_LONG > 32 -- currently broken: it increases power usage under light load */ 60 # define SCHED_LOAD_RESOLUTION 10 61 # define scale_load(w) ((w) << SCHED_LOAD_RESOLUTION) 62 # define scale_load_down(w) ((w) >> SCHED_LOAD_RESOLUTION) 63 #else 64 # define SCHED_LOAD_RESOLUTION 0 65 # define scale_load(w) (w) 66 # define scale_load_down(w) (w) 67 #endif 68 69 #define SCHED_LOAD_SHIFT (10 + SCHED_LOAD_RESOLUTION) 70 #define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT) 71 72 #define NICE_0_LOAD SCHED_LOAD_SCALE 73 #define NICE_0_SHIFT SCHED_LOAD_SHIFT 74 75 /* 76 * These are the 'tuning knobs' of the scheduler: 77 */ 78 79 /* 80 * single value that denotes runtime == period, ie unlimited time. 81 */ 82 #define RUNTIME_INF ((u64)~0ULL) 83 84 static inline int rt_policy(int policy) 85 { 86 if (policy == SCHED_FIFO || policy == SCHED_RR) 87 return 1; 88 return 0; 89 } 90 91 static inline int task_has_rt_policy(struct task_struct *p) 92 { 93 return rt_policy(p->policy); 94 } 95 96 /* 97 * This is the priority-queue data structure of the RT scheduling class: 98 */ 99 struct rt_prio_array { 100 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */ 101 struct list_head queue[MAX_RT_PRIO]; 102 }; 103 104 struct rt_bandwidth { 105 /* nests inside the rq lock: */ 106 raw_spinlock_t rt_runtime_lock; 107 ktime_t rt_period; 108 u64 rt_runtime; 109 struct hrtimer rt_period_timer; 110 }; 111 112 extern struct mutex sched_domains_mutex; 113 114 #ifdef CONFIG_CGROUP_SCHED 115 116 #include <linux/cgroup.h> 117 118 struct cfs_rq; 119 struct rt_rq; 120 121 extern struct list_head task_groups; 122 123 struct cfs_bandwidth { 124 #ifdef CONFIG_CFS_BANDWIDTH 125 raw_spinlock_t lock; 126 ktime_t period; 127 u64 quota, runtime; 128 s64 hierarchal_quota; 129 u64 runtime_expires; 130 131 int idle, timer_active; 132 struct hrtimer period_timer, slack_timer; 133 struct list_head throttled_cfs_rq; 134 135 /* statistics */ 136 int nr_periods, nr_throttled; 137 u64 throttled_time; 138 #endif 139 }; 140 141 /* task group related information */ 142 struct task_group { 143 struct cgroup_subsys_state css; 144 145 #ifdef CONFIG_FAIR_GROUP_SCHED 146 /* schedulable entities of this group on each cpu */ 147 struct sched_entity **se; 148 /* runqueue "owned" by this group on each cpu */ 149 struct cfs_rq **cfs_rq; 150 unsigned long shares; 151 152 #ifdef CONFIG_SMP 153 atomic_long_t load_avg; 154 atomic_t runnable_avg; 155 #endif 156 #endif 157 158 #ifdef CONFIG_RT_GROUP_SCHED 159 struct sched_rt_entity **rt_se; 160 struct rt_rq **rt_rq; 161 162 struct rt_bandwidth rt_bandwidth; 163 #endif 164 165 struct rcu_head rcu; 166 struct list_head list; 167 168 struct task_group *parent; 169 struct list_head siblings; 170 struct list_head children; 171 172 #ifdef CONFIG_SCHED_AUTOGROUP 173 struct autogroup *autogroup; 174 #endif 175 176 struct cfs_bandwidth cfs_bandwidth; 177 }; 178 179 #ifdef CONFIG_FAIR_GROUP_SCHED 180 #define ROOT_TASK_GROUP_LOAD NICE_0_LOAD 181 182 /* 183 * A weight of 0 or 1 can cause arithmetics problems. 184 * A weight of a cfs_rq is the sum of weights of which entities 185 * are queued on this cfs_rq, so a weight of a entity should not be 186 * too large, so as the shares value of a task group. 187 * (The default weight is 1024 - so there's no practical 188 * limitation from this.) 189 */ 190 #define MIN_SHARES (1UL << 1) 191 #define MAX_SHARES (1UL << 18) 192 #endif 193 194 typedef int (*tg_visitor)(struct task_group *, void *); 195 196 extern int walk_tg_tree_from(struct task_group *from, 197 tg_visitor down, tg_visitor up, void *data); 198 199 /* 200 * Iterate the full tree, calling @down when first entering a node and @up when 201 * leaving it for the final time. 202 * 203 * Caller must hold rcu_lock or sufficient equivalent. 204 */ 205 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data) 206 { 207 return walk_tg_tree_from(&root_task_group, down, up, data); 208 } 209 210 extern int tg_nop(struct task_group *tg, void *data); 211 212 extern void free_fair_sched_group(struct task_group *tg); 213 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent); 214 extern void unregister_fair_sched_group(struct task_group *tg, int cpu); 215 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, 216 struct sched_entity *se, int cpu, 217 struct sched_entity *parent); 218 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b); 219 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); 220 221 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b); 222 extern void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b); 223 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq); 224 225 extern void free_rt_sched_group(struct task_group *tg); 226 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent); 227 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, 228 struct sched_rt_entity *rt_se, int cpu, 229 struct sched_rt_entity *parent); 230 231 extern struct task_group *sched_create_group(struct task_group *parent); 232 extern void sched_online_group(struct task_group *tg, 233 struct task_group *parent); 234 extern void sched_destroy_group(struct task_group *tg); 235 extern void sched_offline_group(struct task_group *tg); 236 237 extern void sched_move_task(struct task_struct *tsk); 238 239 #ifdef CONFIG_FAIR_GROUP_SCHED 240 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); 241 #endif 242 243 #else /* CONFIG_CGROUP_SCHED */ 244 245 struct cfs_bandwidth { }; 246 247 #endif /* CONFIG_CGROUP_SCHED */ 248 249 /* CFS-related fields in a runqueue */ 250 struct cfs_rq { 251 struct load_weight load; 252 unsigned int nr_running, h_nr_running; 253 254 u64 exec_clock; 255 u64 min_vruntime; 256 #ifndef CONFIG_64BIT 257 u64 min_vruntime_copy; 258 #endif 259 260 struct rb_root tasks_timeline; 261 struct rb_node *rb_leftmost; 262 263 /* 264 * 'curr' points to currently running entity on this cfs_rq. 265 * It is set to NULL otherwise (i.e when none are currently running). 266 */ 267 struct sched_entity *curr, *next, *last, *skip; 268 269 #ifdef CONFIG_SCHED_DEBUG 270 unsigned int nr_spread_over; 271 #endif 272 273 #ifdef CONFIG_SMP 274 /* 275 * CFS Load tracking 276 * Under CFS, load is tracked on a per-entity basis and aggregated up. 277 * This allows for the description of both thread and group usage (in 278 * the FAIR_GROUP_SCHED case). 279 */ 280 unsigned long runnable_load_avg, blocked_load_avg; 281 atomic64_t decay_counter; 282 u64 last_decay; 283 atomic_long_t removed_load; 284 285 #ifdef CONFIG_FAIR_GROUP_SCHED 286 /* Required to track per-cpu representation of a task_group */ 287 u32 tg_runnable_contrib; 288 unsigned long tg_load_contrib; 289 290 /* 291 * h_load = weight * f(tg) 292 * 293 * Where f(tg) is the recursive weight fraction assigned to 294 * this group. 295 */ 296 unsigned long h_load; 297 u64 last_h_load_update; 298 struct sched_entity *h_load_next; 299 #endif /* CONFIG_FAIR_GROUP_SCHED */ 300 #endif /* CONFIG_SMP */ 301 302 #ifdef CONFIG_FAIR_GROUP_SCHED 303 struct rq *rq; /* cpu runqueue to which this cfs_rq is attached */ 304 305 /* 306 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in 307 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities 308 * (like users, containers etc.) 309 * 310 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This 311 * list is used during load balance. 312 */ 313 int on_list; 314 struct list_head leaf_cfs_rq_list; 315 struct task_group *tg; /* group that "owns" this runqueue */ 316 317 #ifdef CONFIG_CFS_BANDWIDTH 318 int runtime_enabled; 319 u64 runtime_expires; 320 s64 runtime_remaining; 321 322 u64 throttled_clock, throttled_clock_task; 323 u64 throttled_clock_task_time; 324 int throttled, throttle_count; 325 struct list_head throttled_list; 326 #endif /* CONFIG_CFS_BANDWIDTH */ 327 #endif /* CONFIG_FAIR_GROUP_SCHED */ 328 }; 329 330 static inline int rt_bandwidth_enabled(void) 331 { 332 return sysctl_sched_rt_runtime >= 0; 333 } 334 335 /* Real-Time classes' related field in a runqueue: */ 336 struct rt_rq { 337 struct rt_prio_array active; 338 unsigned int rt_nr_running; 339 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED 340 struct { 341 int curr; /* highest queued rt task prio */ 342 #ifdef CONFIG_SMP 343 int next; /* next highest */ 344 #endif 345 } highest_prio; 346 #endif 347 #ifdef CONFIG_SMP 348 unsigned long rt_nr_migratory; 349 unsigned long rt_nr_total; 350 int overloaded; 351 struct plist_head pushable_tasks; 352 #endif 353 int rt_throttled; 354 u64 rt_time; 355 u64 rt_runtime; 356 /* Nests inside the rq lock: */ 357 raw_spinlock_t rt_runtime_lock; 358 359 #ifdef CONFIG_RT_GROUP_SCHED 360 unsigned long rt_nr_boosted; 361 362 struct rq *rq; 363 struct task_group *tg; 364 #endif 365 }; 366 367 #ifdef CONFIG_SMP 368 369 /* 370 * We add the notion of a root-domain which will be used to define per-domain 371 * variables. Each exclusive cpuset essentially defines an island domain by 372 * fully partitioning the member cpus from any other cpuset. Whenever a new 373 * exclusive cpuset is created, we also create and attach a new root-domain 374 * object. 375 * 376 */ 377 struct root_domain { 378 atomic_t refcount; 379 atomic_t rto_count; 380 struct rcu_head rcu; 381 cpumask_var_t span; 382 cpumask_var_t online; 383 384 /* 385 * The "RT overload" flag: it gets set if a CPU has more than 386 * one runnable RT task. 387 */ 388 cpumask_var_t rto_mask; 389 struct cpupri cpupri; 390 }; 391 392 extern struct root_domain def_root_domain; 393 394 #endif /* CONFIG_SMP */ 395 396 /* 397 * This is the main, per-CPU runqueue data structure. 398 * 399 * Locking rule: those places that want to lock multiple runqueues 400 * (such as the load balancing or the thread migration code), lock 401 * acquire operations must be ordered by ascending &runqueue. 402 */ 403 struct rq { 404 /* runqueue lock: */ 405 raw_spinlock_t lock; 406 407 /* 408 * nr_running and cpu_load should be in the same cacheline because 409 * remote CPUs use both these fields when doing load calculation. 410 */ 411 unsigned int nr_running; 412 #ifdef CONFIG_NUMA_BALANCING 413 unsigned int nr_numa_running; 414 unsigned int nr_preferred_running; 415 #endif 416 #define CPU_LOAD_IDX_MAX 5 417 unsigned long cpu_load[CPU_LOAD_IDX_MAX]; 418 unsigned long last_load_update_tick; 419 #ifdef CONFIG_NO_HZ_COMMON 420 u64 nohz_stamp; 421 unsigned long nohz_flags; 422 #endif 423 #ifdef CONFIG_NO_HZ_FULL 424 unsigned long last_sched_tick; 425 #endif 426 int skip_clock_update; 427 428 /* capture load from *all* tasks on this cpu: */ 429 struct load_weight load; 430 unsigned long nr_load_updates; 431 u64 nr_switches; 432 433 struct cfs_rq cfs; 434 struct rt_rq rt; 435 436 #ifdef CONFIG_FAIR_GROUP_SCHED 437 /* list of leaf cfs_rq on this cpu: */ 438 struct list_head leaf_cfs_rq_list; 439 #endif /* CONFIG_FAIR_GROUP_SCHED */ 440 441 #ifdef CONFIG_RT_GROUP_SCHED 442 struct list_head leaf_rt_rq_list; 443 #endif 444 445 /* 446 * This is part of a global counter where only the total sum 447 * over all CPUs matters. A task can increase this counter on 448 * one CPU and if it got migrated afterwards it may decrease 449 * it on another CPU. Always updated under the runqueue lock: 450 */ 451 unsigned long nr_uninterruptible; 452 453 struct task_struct *curr, *idle, *stop; 454 unsigned long next_balance; 455 struct mm_struct *prev_mm; 456 457 u64 clock; 458 u64 clock_task; 459 460 atomic_t nr_iowait; 461 462 #ifdef CONFIG_SMP 463 struct root_domain *rd; 464 struct sched_domain *sd; 465 466 unsigned long cpu_power; 467 468 unsigned char idle_balance; 469 /* For active balancing */ 470 int post_schedule; 471 int active_balance; 472 int push_cpu; 473 struct cpu_stop_work active_balance_work; 474 /* cpu of this runqueue: */ 475 int cpu; 476 int online; 477 478 struct list_head cfs_tasks; 479 480 u64 rt_avg; 481 u64 age_stamp; 482 u64 idle_stamp; 483 u64 avg_idle; 484 485 /* This is used to determine avg_idle's max value */ 486 u64 max_idle_balance_cost; 487 #endif 488 489 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 490 u64 prev_irq_time; 491 #endif 492 #ifdef CONFIG_PARAVIRT 493 u64 prev_steal_time; 494 #endif 495 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING 496 u64 prev_steal_time_rq; 497 #endif 498 499 /* calc_load related fields */ 500 unsigned long calc_load_update; 501 long calc_load_active; 502 503 #ifdef CONFIG_SCHED_HRTICK 504 #ifdef CONFIG_SMP 505 int hrtick_csd_pending; 506 struct call_single_data hrtick_csd; 507 #endif 508 struct hrtimer hrtick_timer; 509 #endif 510 511 #ifdef CONFIG_SCHEDSTATS 512 /* latency stats */ 513 struct sched_info rq_sched_info; 514 unsigned long long rq_cpu_time; 515 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */ 516 517 /* sys_sched_yield() stats */ 518 unsigned int yld_count; 519 520 /* schedule() stats */ 521 unsigned int sched_count; 522 unsigned int sched_goidle; 523 524 /* try_to_wake_up() stats */ 525 unsigned int ttwu_count; 526 unsigned int ttwu_local; 527 #endif 528 529 #ifdef CONFIG_SMP 530 struct llist_head wake_list; 531 #endif 532 533 struct sched_avg avg; 534 }; 535 536 static inline int cpu_of(struct rq *rq) 537 { 538 #ifdef CONFIG_SMP 539 return rq->cpu; 540 #else 541 return 0; 542 #endif 543 } 544 545 DECLARE_PER_CPU(struct rq, runqueues); 546 547 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) 548 #define this_rq() (&__get_cpu_var(runqueues)) 549 #define task_rq(p) cpu_rq(task_cpu(p)) 550 #define cpu_curr(cpu) (cpu_rq(cpu)->curr) 551 #define raw_rq() (&__raw_get_cpu_var(runqueues)) 552 553 static inline u64 rq_clock(struct rq *rq) 554 { 555 return rq->clock; 556 } 557 558 static inline u64 rq_clock_task(struct rq *rq) 559 { 560 return rq->clock_task; 561 } 562 563 #ifdef CONFIG_NUMA_BALANCING 564 extern void sched_setnuma(struct task_struct *p, int node); 565 extern int migrate_task_to(struct task_struct *p, int cpu); 566 extern int migrate_swap(struct task_struct *, struct task_struct *); 567 #endif /* CONFIG_NUMA_BALANCING */ 568 569 #ifdef CONFIG_SMP 570 571 #define rcu_dereference_check_sched_domain(p) \ 572 rcu_dereference_check((p), \ 573 lockdep_is_held(&sched_domains_mutex)) 574 575 /* 576 * The domain tree (rq->sd) is protected by RCU's quiescent state transition. 577 * See detach_destroy_domains: synchronize_sched for details. 578 * 579 * The domain tree of any CPU may only be accessed from within 580 * preempt-disabled sections. 581 */ 582 #define for_each_domain(cpu, __sd) \ 583 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \ 584 __sd; __sd = __sd->parent) 585 586 #define for_each_lower_domain(sd) for (; sd; sd = sd->child) 587 588 /** 589 * highest_flag_domain - Return highest sched_domain containing flag. 590 * @cpu: The cpu whose highest level of sched domain is to 591 * be returned. 592 * @flag: The flag to check for the highest sched_domain 593 * for the given cpu. 594 * 595 * Returns the highest sched_domain of a cpu which contains the given flag. 596 */ 597 static inline struct sched_domain *highest_flag_domain(int cpu, int flag) 598 { 599 struct sched_domain *sd, *hsd = NULL; 600 601 for_each_domain(cpu, sd) { 602 if (!(sd->flags & flag)) 603 break; 604 hsd = sd; 605 } 606 607 return hsd; 608 } 609 610 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) 611 { 612 struct sched_domain *sd; 613 614 for_each_domain(cpu, sd) { 615 if (sd->flags & flag) 616 break; 617 } 618 619 return sd; 620 } 621 622 DECLARE_PER_CPU(struct sched_domain *, sd_llc); 623 DECLARE_PER_CPU(int, sd_llc_size); 624 DECLARE_PER_CPU(int, sd_llc_id); 625 DECLARE_PER_CPU(struct sched_domain *, sd_numa); 626 DECLARE_PER_CPU(struct sched_domain *, sd_busy); 627 DECLARE_PER_CPU(struct sched_domain *, sd_asym); 628 629 struct sched_group_power { 630 atomic_t ref; 631 /* 632 * CPU power of this group, SCHED_LOAD_SCALE being max power for a 633 * single CPU. 634 */ 635 unsigned int power, power_orig; 636 unsigned long next_update; 637 int imbalance; /* XXX unrelated to power but shared group state */ 638 /* 639 * Number of busy cpus in this group. 640 */ 641 atomic_t nr_busy_cpus; 642 643 unsigned long cpumask[0]; /* iteration mask */ 644 }; 645 646 struct sched_group { 647 struct sched_group *next; /* Must be a circular list */ 648 atomic_t ref; 649 650 unsigned int group_weight; 651 struct sched_group_power *sgp; 652 653 /* 654 * The CPUs this group covers. 655 * 656 * NOTE: this field is variable length. (Allocated dynamically 657 * by attaching extra space to the end of the structure, 658 * depending on how many CPUs the kernel has booted up with) 659 */ 660 unsigned long cpumask[0]; 661 }; 662 663 static inline struct cpumask *sched_group_cpus(struct sched_group *sg) 664 { 665 return to_cpumask(sg->cpumask); 666 } 667 668 /* 669 * cpumask masking which cpus in the group are allowed to iterate up the domain 670 * tree. 671 */ 672 static inline struct cpumask *sched_group_mask(struct sched_group *sg) 673 { 674 return to_cpumask(sg->sgp->cpumask); 675 } 676 677 /** 678 * group_first_cpu - Returns the first cpu in the cpumask of a sched_group. 679 * @group: The group whose first cpu is to be returned. 680 */ 681 static inline unsigned int group_first_cpu(struct sched_group *group) 682 { 683 return cpumask_first(sched_group_cpus(group)); 684 } 685 686 extern int group_balance_cpu(struct sched_group *sg); 687 688 #endif /* CONFIG_SMP */ 689 690 #include "stats.h" 691 #include "auto_group.h" 692 693 #ifdef CONFIG_CGROUP_SCHED 694 695 /* 696 * Return the group to which this tasks belongs. 697 * 698 * We cannot use task_css() and friends because the cgroup subsystem 699 * changes that value before the cgroup_subsys::attach() method is called, 700 * therefore we cannot pin it and might observe the wrong value. 701 * 702 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup 703 * core changes this before calling sched_move_task(). 704 * 705 * Instead we use a 'copy' which is updated from sched_move_task() while 706 * holding both task_struct::pi_lock and rq::lock. 707 */ 708 static inline struct task_group *task_group(struct task_struct *p) 709 { 710 return p->sched_task_group; 711 } 712 713 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ 714 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) 715 { 716 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED) 717 struct task_group *tg = task_group(p); 718 #endif 719 720 #ifdef CONFIG_FAIR_GROUP_SCHED 721 p->se.cfs_rq = tg->cfs_rq[cpu]; 722 p->se.parent = tg->se[cpu]; 723 #endif 724 725 #ifdef CONFIG_RT_GROUP_SCHED 726 p->rt.rt_rq = tg->rt_rq[cpu]; 727 p->rt.parent = tg->rt_se[cpu]; 728 #endif 729 } 730 731 #else /* CONFIG_CGROUP_SCHED */ 732 733 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } 734 static inline struct task_group *task_group(struct task_struct *p) 735 { 736 return NULL; 737 } 738 739 #endif /* CONFIG_CGROUP_SCHED */ 740 741 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) 742 { 743 set_task_rq(p, cpu); 744 #ifdef CONFIG_SMP 745 /* 746 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be 747 * successfuly executed on another CPU. We must ensure that updates of 748 * per-task data have been completed by this moment. 749 */ 750 smp_wmb(); 751 task_thread_info(p)->cpu = cpu; 752 p->wake_cpu = cpu; 753 #endif 754 } 755 756 /* 757 * Tunables that become constants when CONFIG_SCHED_DEBUG is off: 758 */ 759 #ifdef CONFIG_SCHED_DEBUG 760 # include <linux/static_key.h> 761 # define const_debug __read_mostly 762 #else 763 # define const_debug const 764 #endif 765 766 extern const_debug unsigned int sysctl_sched_features; 767 768 #define SCHED_FEAT(name, enabled) \ 769 __SCHED_FEAT_##name , 770 771 enum { 772 #include "features.h" 773 __SCHED_FEAT_NR, 774 }; 775 776 #undef SCHED_FEAT 777 778 #if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL) 779 static __always_inline bool static_branch__true(struct static_key *key) 780 { 781 return static_key_true(key); /* Not out of line branch. */ 782 } 783 784 static __always_inline bool static_branch__false(struct static_key *key) 785 { 786 return static_key_false(key); /* Out of line branch. */ 787 } 788 789 #define SCHED_FEAT(name, enabled) \ 790 static __always_inline bool static_branch_##name(struct static_key *key) \ 791 { \ 792 return static_branch__##enabled(key); \ 793 } 794 795 #include "features.h" 796 797 #undef SCHED_FEAT 798 799 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR]; 800 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x])) 801 #else /* !(SCHED_DEBUG && HAVE_JUMP_LABEL) */ 802 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) 803 #endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */ 804 805 #ifdef CONFIG_NUMA_BALANCING 806 #define sched_feat_numa(x) sched_feat(x) 807 #ifdef CONFIG_SCHED_DEBUG 808 #define numabalancing_enabled sched_feat_numa(NUMA) 809 #else 810 extern bool numabalancing_enabled; 811 #endif /* CONFIG_SCHED_DEBUG */ 812 #else 813 #define sched_feat_numa(x) (0) 814 #define numabalancing_enabled (0) 815 #endif /* CONFIG_NUMA_BALANCING */ 816 817 static inline u64 global_rt_period(void) 818 { 819 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC; 820 } 821 822 static inline u64 global_rt_runtime(void) 823 { 824 if (sysctl_sched_rt_runtime < 0) 825 return RUNTIME_INF; 826 827 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC; 828 } 829 830 831 832 static inline int task_current(struct rq *rq, struct task_struct *p) 833 { 834 return rq->curr == p; 835 } 836 837 static inline int task_running(struct rq *rq, struct task_struct *p) 838 { 839 #ifdef CONFIG_SMP 840 return p->on_cpu; 841 #else 842 return task_current(rq, p); 843 #endif 844 } 845 846 847 #ifndef prepare_arch_switch 848 # define prepare_arch_switch(next) do { } while (0) 849 #endif 850 #ifndef finish_arch_switch 851 # define finish_arch_switch(prev) do { } while (0) 852 #endif 853 #ifndef finish_arch_post_lock_switch 854 # define finish_arch_post_lock_switch() do { } while (0) 855 #endif 856 857 #ifndef __ARCH_WANT_UNLOCKED_CTXSW 858 static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) 859 { 860 #ifdef CONFIG_SMP 861 /* 862 * We can optimise this out completely for !SMP, because the 863 * SMP rebalancing from interrupt is the only thing that cares 864 * here. 865 */ 866 next->on_cpu = 1; 867 #endif 868 } 869 870 static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) 871 { 872 #ifdef CONFIG_SMP 873 /* 874 * After ->on_cpu is cleared, the task can be moved to a different CPU. 875 * We must ensure this doesn't happen until the switch is completely 876 * finished. 877 */ 878 smp_wmb(); 879 prev->on_cpu = 0; 880 #endif 881 #ifdef CONFIG_DEBUG_SPINLOCK 882 /* this is a valid case when another task releases the spinlock */ 883 rq->lock.owner = current; 884 #endif 885 /* 886 * If we are tracking spinlock dependencies then we have to 887 * fix up the runqueue lock - which gets 'carried over' from 888 * prev into current: 889 */ 890 spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_); 891 892 raw_spin_unlock_irq(&rq->lock); 893 } 894 895 #else /* __ARCH_WANT_UNLOCKED_CTXSW */ 896 static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) 897 { 898 #ifdef CONFIG_SMP 899 /* 900 * We can optimise this out completely for !SMP, because the 901 * SMP rebalancing from interrupt is the only thing that cares 902 * here. 903 */ 904 next->on_cpu = 1; 905 #endif 906 raw_spin_unlock(&rq->lock); 907 } 908 909 static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) 910 { 911 #ifdef CONFIG_SMP 912 /* 913 * After ->on_cpu is cleared, the task can be moved to a different CPU. 914 * We must ensure this doesn't happen until the switch is completely 915 * finished. 916 */ 917 smp_wmb(); 918 prev->on_cpu = 0; 919 #endif 920 local_irq_enable(); 921 } 922 #endif /* __ARCH_WANT_UNLOCKED_CTXSW */ 923 924 /* 925 * wake flags 926 */ 927 #define WF_SYNC 0x01 /* waker goes to sleep after wakeup */ 928 #define WF_FORK 0x02 /* child wakeup after fork */ 929 #define WF_MIGRATED 0x4 /* internal use, task got migrated */ 930 931 /* 932 * To aid in avoiding the subversion of "niceness" due to uneven distribution 933 * of tasks with abnormal "nice" values across CPUs the contribution that 934 * each task makes to its run queue's load is weighted according to its 935 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a 936 * scaled version of the new time slice allocation that they receive on time 937 * slice expiry etc. 938 */ 939 940 #define WEIGHT_IDLEPRIO 3 941 #define WMULT_IDLEPRIO 1431655765 942 943 /* 944 * Nice levels are multiplicative, with a gentle 10% change for every 945 * nice level changed. I.e. when a CPU-bound task goes from nice 0 to 946 * nice 1, it will get ~10% less CPU time than another CPU-bound task 947 * that remained on nice 0. 948 * 949 * The "10% effect" is relative and cumulative: from _any_ nice level, 950 * if you go up 1 level, it's -10% CPU usage, if you go down 1 level 951 * it's +10% CPU usage. (to achieve that we use a multiplier of 1.25. 952 * If a task goes up by ~10% and another task goes down by ~10% then 953 * the relative distance between them is ~25%.) 954 */ 955 static const int prio_to_weight[40] = { 956 /* -20 */ 88761, 71755, 56483, 46273, 36291, 957 /* -15 */ 29154, 23254, 18705, 14949, 11916, 958 /* -10 */ 9548, 7620, 6100, 4904, 3906, 959 /* -5 */ 3121, 2501, 1991, 1586, 1277, 960 /* 0 */ 1024, 820, 655, 526, 423, 961 /* 5 */ 335, 272, 215, 172, 137, 962 /* 10 */ 110, 87, 70, 56, 45, 963 /* 15 */ 36, 29, 23, 18, 15, 964 }; 965 966 /* 967 * Inverse (2^32/x) values of the prio_to_weight[] array, precalculated. 968 * 969 * In cases where the weight does not change often, we can use the 970 * precalculated inverse to speed up arithmetics by turning divisions 971 * into multiplications: 972 */ 973 static const u32 prio_to_wmult[40] = { 974 /* -20 */ 48388, 59856, 76040, 92818, 118348, 975 /* -15 */ 147320, 184698, 229616, 287308, 360437, 976 /* -10 */ 449829, 563644, 704093, 875809, 1099582, 977 /* -5 */ 1376151, 1717300, 2157191, 2708050, 3363326, 978 /* 0 */ 4194304, 5237765, 6557202, 8165337, 10153587, 979 /* 5 */ 12820798, 15790321, 19976592, 24970740, 31350126, 980 /* 10 */ 39045157, 49367440, 61356676, 76695844, 95443717, 981 /* 15 */ 119304647, 148102320, 186737708, 238609294, 286331153, 982 }; 983 984 #define ENQUEUE_WAKEUP 1 985 #define ENQUEUE_HEAD 2 986 #ifdef CONFIG_SMP 987 #define ENQUEUE_WAKING 4 /* sched_class::task_waking was called */ 988 #else 989 #define ENQUEUE_WAKING 0 990 #endif 991 992 #define DEQUEUE_SLEEP 1 993 994 struct sched_class { 995 const struct sched_class *next; 996 997 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags); 998 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags); 999 void (*yield_task) (struct rq *rq); 1000 bool (*yield_to_task) (struct rq *rq, struct task_struct *p, bool preempt); 1001 1002 void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags); 1003 1004 struct task_struct * (*pick_next_task) (struct rq *rq); 1005 void (*put_prev_task) (struct rq *rq, struct task_struct *p); 1006 1007 #ifdef CONFIG_SMP 1008 int (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags); 1009 void (*migrate_task_rq)(struct task_struct *p, int next_cpu); 1010 1011 void (*pre_schedule) (struct rq *this_rq, struct task_struct *task); 1012 void (*post_schedule) (struct rq *this_rq); 1013 void (*task_waking) (struct task_struct *task); 1014 void (*task_woken) (struct rq *this_rq, struct task_struct *task); 1015 1016 void (*set_cpus_allowed)(struct task_struct *p, 1017 const struct cpumask *newmask); 1018 1019 void (*rq_online)(struct rq *rq); 1020 void (*rq_offline)(struct rq *rq); 1021 #endif 1022 1023 void (*set_curr_task) (struct rq *rq); 1024 void (*task_tick) (struct rq *rq, struct task_struct *p, int queued); 1025 void (*task_fork) (struct task_struct *p); 1026 1027 void (*switched_from) (struct rq *this_rq, struct task_struct *task); 1028 void (*switched_to) (struct rq *this_rq, struct task_struct *task); 1029 void (*prio_changed) (struct rq *this_rq, struct task_struct *task, 1030 int oldprio); 1031 1032 unsigned int (*get_rr_interval) (struct rq *rq, 1033 struct task_struct *task); 1034 1035 #ifdef CONFIG_FAIR_GROUP_SCHED 1036 void (*task_move_group) (struct task_struct *p, int on_rq); 1037 #endif 1038 }; 1039 1040 #define sched_class_highest (&stop_sched_class) 1041 #define for_each_class(class) \ 1042 for (class = sched_class_highest; class; class = class->next) 1043 1044 extern const struct sched_class stop_sched_class; 1045 extern const struct sched_class rt_sched_class; 1046 extern const struct sched_class fair_sched_class; 1047 extern const struct sched_class idle_sched_class; 1048 1049 1050 #ifdef CONFIG_SMP 1051 1052 extern void update_group_power(struct sched_domain *sd, int cpu); 1053 1054 extern void trigger_load_balance(struct rq *rq, int cpu); 1055 extern void idle_balance(int this_cpu, struct rq *this_rq); 1056 1057 extern void idle_enter_fair(struct rq *this_rq); 1058 extern void idle_exit_fair(struct rq *this_rq); 1059 1060 #else /* CONFIG_SMP */ 1061 1062 static inline void idle_balance(int cpu, struct rq *rq) 1063 { 1064 } 1065 1066 #endif 1067 1068 extern void sysrq_sched_debug_show(void); 1069 extern void sched_init_granularity(void); 1070 extern void update_max_interval(void); 1071 extern void init_sched_rt_class(void); 1072 extern void init_sched_fair_class(void); 1073 1074 extern void resched_task(struct task_struct *p); 1075 extern void resched_cpu(int cpu); 1076 1077 extern struct rt_bandwidth def_rt_bandwidth; 1078 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime); 1079 1080 extern void update_idle_cpu_load(struct rq *this_rq); 1081 1082 extern void init_task_runnable_average(struct task_struct *p); 1083 1084 #ifdef CONFIG_PARAVIRT 1085 static inline u64 steal_ticks(u64 steal) 1086 { 1087 if (unlikely(steal > NSEC_PER_SEC)) 1088 return div_u64(steal, TICK_NSEC); 1089 1090 return __iter_div_u64_rem(steal, TICK_NSEC, &steal); 1091 } 1092 #endif 1093 1094 static inline void inc_nr_running(struct rq *rq) 1095 { 1096 rq->nr_running++; 1097 1098 #ifdef CONFIG_NO_HZ_FULL 1099 if (rq->nr_running == 2) { 1100 if (tick_nohz_full_cpu(rq->cpu)) { 1101 /* Order rq->nr_running write against the IPI */ 1102 smp_wmb(); 1103 smp_send_reschedule(rq->cpu); 1104 } 1105 } 1106 #endif 1107 } 1108 1109 static inline void dec_nr_running(struct rq *rq) 1110 { 1111 rq->nr_running--; 1112 } 1113 1114 static inline void rq_last_tick_reset(struct rq *rq) 1115 { 1116 #ifdef CONFIG_NO_HZ_FULL 1117 rq->last_sched_tick = jiffies; 1118 #endif 1119 } 1120 1121 extern void update_rq_clock(struct rq *rq); 1122 1123 extern void activate_task(struct rq *rq, struct task_struct *p, int flags); 1124 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags); 1125 1126 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags); 1127 1128 extern const_debug unsigned int sysctl_sched_time_avg; 1129 extern const_debug unsigned int sysctl_sched_nr_migrate; 1130 extern const_debug unsigned int sysctl_sched_migration_cost; 1131 1132 static inline u64 sched_avg_period(void) 1133 { 1134 return (u64)sysctl_sched_time_avg * NSEC_PER_MSEC / 2; 1135 } 1136 1137 #ifdef CONFIG_SCHED_HRTICK 1138 1139 /* 1140 * Use hrtick when: 1141 * - enabled by features 1142 * - hrtimer is actually high res 1143 */ 1144 static inline int hrtick_enabled(struct rq *rq) 1145 { 1146 if (!sched_feat(HRTICK)) 1147 return 0; 1148 if (!cpu_active(cpu_of(rq))) 1149 return 0; 1150 return hrtimer_is_hres_active(&rq->hrtick_timer); 1151 } 1152 1153 void hrtick_start(struct rq *rq, u64 delay); 1154 1155 #else 1156 1157 static inline int hrtick_enabled(struct rq *rq) 1158 { 1159 return 0; 1160 } 1161 1162 #endif /* CONFIG_SCHED_HRTICK */ 1163 1164 #ifdef CONFIG_SMP 1165 extern void sched_avg_update(struct rq *rq); 1166 static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) 1167 { 1168 rq->rt_avg += rt_delta; 1169 sched_avg_update(rq); 1170 } 1171 #else 1172 static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { } 1173 static inline void sched_avg_update(struct rq *rq) { } 1174 #endif 1175 1176 extern void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period); 1177 1178 #ifdef CONFIG_SMP 1179 #ifdef CONFIG_PREEMPT 1180 1181 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2); 1182 1183 /* 1184 * fair double_lock_balance: Safely acquires both rq->locks in a fair 1185 * way at the expense of forcing extra atomic operations in all 1186 * invocations. This assures that the double_lock is acquired using the 1187 * same underlying policy as the spinlock_t on this architecture, which 1188 * reduces latency compared to the unfair variant below. However, it 1189 * also adds more overhead and therefore may reduce throughput. 1190 */ 1191 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 1192 __releases(this_rq->lock) 1193 __acquires(busiest->lock) 1194 __acquires(this_rq->lock) 1195 { 1196 raw_spin_unlock(&this_rq->lock); 1197 double_rq_lock(this_rq, busiest); 1198 1199 return 1; 1200 } 1201 1202 #else 1203 /* 1204 * Unfair double_lock_balance: Optimizes throughput at the expense of 1205 * latency by eliminating extra atomic operations when the locks are 1206 * already in proper order on entry. This favors lower cpu-ids and will 1207 * grant the double lock to lower cpus over higher ids under contention, 1208 * regardless of entry order into the function. 1209 */ 1210 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 1211 __releases(this_rq->lock) 1212 __acquires(busiest->lock) 1213 __acquires(this_rq->lock) 1214 { 1215 int ret = 0; 1216 1217 if (unlikely(!raw_spin_trylock(&busiest->lock))) { 1218 if (busiest < this_rq) { 1219 raw_spin_unlock(&this_rq->lock); 1220 raw_spin_lock(&busiest->lock); 1221 raw_spin_lock_nested(&this_rq->lock, 1222 SINGLE_DEPTH_NESTING); 1223 ret = 1; 1224 } else 1225 raw_spin_lock_nested(&busiest->lock, 1226 SINGLE_DEPTH_NESTING); 1227 } 1228 return ret; 1229 } 1230 1231 #endif /* CONFIG_PREEMPT */ 1232 1233 /* 1234 * double_lock_balance - lock the busiest runqueue, this_rq is locked already. 1235 */ 1236 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest) 1237 { 1238 if (unlikely(!irqs_disabled())) { 1239 /* printk() doesn't work good under rq->lock */ 1240 raw_spin_unlock(&this_rq->lock); 1241 BUG_ON(1); 1242 } 1243 1244 return _double_lock_balance(this_rq, busiest); 1245 } 1246 1247 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest) 1248 __releases(busiest->lock) 1249 { 1250 raw_spin_unlock(&busiest->lock); 1251 lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_); 1252 } 1253 1254 static inline void double_lock(spinlock_t *l1, spinlock_t *l2) 1255 { 1256 if (l1 > l2) 1257 swap(l1, l2); 1258 1259 spin_lock(l1); 1260 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 1261 } 1262 1263 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2) 1264 { 1265 if (l1 > l2) 1266 swap(l1, l2); 1267 1268 raw_spin_lock(l1); 1269 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 1270 } 1271 1272 /* 1273 * double_rq_lock - safely lock two runqueues 1274 * 1275 * Note this does not disable interrupts like task_rq_lock, 1276 * you need to do so manually before calling. 1277 */ 1278 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2) 1279 __acquires(rq1->lock) 1280 __acquires(rq2->lock) 1281 { 1282 BUG_ON(!irqs_disabled()); 1283 if (rq1 == rq2) { 1284 raw_spin_lock(&rq1->lock); 1285 __acquire(rq2->lock); /* Fake it out ;) */ 1286 } else { 1287 if (rq1 < rq2) { 1288 raw_spin_lock(&rq1->lock); 1289 raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING); 1290 } else { 1291 raw_spin_lock(&rq2->lock); 1292 raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING); 1293 } 1294 } 1295 } 1296 1297 /* 1298 * double_rq_unlock - safely unlock two runqueues 1299 * 1300 * Note this does not restore interrupts like task_rq_unlock, 1301 * you need to do so manually after calling. 1302 */ 1303 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 1304 __releases(rq1->lock) 1305 __releases(rq2->lock) 1306 { 1307 raw_spin_unlock(&rq1->lock); 1308 if (rq1 != rq2) 1309 raw_spin_unlock(&rq2->lock); 1310 else 1311 __release(rq2->lock); 1312 } 1313 1314 #else /* CONFIG_SMP */ 1315 1316 /* 1317 * double_rq_lock - safely lock two runqueues 1318 * 1319 * Note this does not disable interrupts like task_rq_lock, 1320 * you need to do so manually before calling. 1321 */ 1322 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2) 1323 __acquires(rq1->lock) 1324 __acquires(rq2->lock) 1325 { 1326 BUG_ON(!irqs_disabled()); 1327 BUG_ON(rq1 != rq2); 1328 raw_spin_lock(&rq1->lock); 1329 __acquire(rq2->lock); /* Fake it out ;) */ 1330 } 1331 1332 /* 1333 * double_rq_unlock - safely unlock two runqueues 1334 * 1335 * Note this does not restore interrupts like task_rq_unlock, 1336 * you need to do so manually after calling. 1337 */ 1338 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 1339 __releases(rq1->lock) 1340 __releases(rq2->lock) 1341 { 1342 BUG_ON(rq1 != rq2); 1343 raw_spin_unlock(&rq1->lock); 1344 __release(rq2->lock); 1345 } 1346 1347 #endif 1348 1349 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq); 1350 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq); 1351 extern void print_cfs_stats(struct seq_file *m, int cpu); 1352 extern void print_rt_stats(struct seq_file *m, int cpu); 1353 1354 extern void init_cfs_rq(struct cfs_rq *cfs_rq); 1355 extern void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq); 1356 1357 extern void cfs_bandwidth_usage_inc(void); 1358 extern void cfs_bandwidth_usage_dec(void); 1359 1360 #ifdef CONFIG_NO_HZ_COMMON 1361 enum rq_nohz_flag_bits { 1362 NOHZ_TICK_STOPPED, 1363 NOHZ_BALANCE_KICK, 1364 }; 1365 1366 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags) 1367 #endif 1368 1369 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 1370 1371 DECLARE_PER_CPU(u64, cpu_hardirq_time); 1372 DECLARE_PER_CPU(u64, cpu_softirq_time); 1373 1374 #ifndef CONFIG_64BIT 1375 DECLARE_PER_CPU(seqcount_t, irq_time_seq); 1376 1377 static inline void irq_time_write_begin(void) 1378 { 1379 __this_cpu_inc(irq_time_seq.sequence); 1380 smp_wmb(); 1381 } 1382 1383 static inline void irq_time_write_end(void) 1384 { 1385 smp_wmb(); 1386 __this_cpu_inc(irq_time_seq.sequence); 1387 } 1388 1389 static inline u64 irq_time_read(int cpu) 1390 { 1391 u64 irq_time; 1392 unsigned seq; 1393 1394 do { 1395 seq = read_seqcount_begin(&per_cpu(irq_time_seq, cpu)); 1396 irq_time = per_cpu(cpu_softirq_time, cpu) + 1397 per_cpu(cpu_hardirq_time, cpu); 1398 } while (read_seqcount_retry(&per_cpu(irq_time_seq, cpu), seq)); 1399 1400 return irq_time; 1401 } 1402 #else /* CONFIG_64BIT */ 1403 static inline void irq_time_write_begin(void) 1404 { 1405 } 1406 1407 static inline void irq_time_write_end(void) 1408 { 1409 } 1410 1411 static inline u64 irq_time_read(int cpu) 1412 { 1413 return per_cpu(cpu_softirq_time, cpu) + per_cpu(cpu_hardirq_time, cpu); 1414 } 1415 #endif /* CONFIG_64BIT */ 1416 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */ 1417