1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Scheduler internal types and methods: 4 */ 5 #include <linux/sched.h> 6 7 #include <linux/sched/autogroup.h> 8 #include <linux/sched/clock.h> 9 #include <linux/sched/coredump.h> 10 #include <linux/sched/cpufreq.h> 11 #include <linux/sched/cputime.h> 12 #include <linux/sched/deadline.h> 13 #include <linux/sched/debug.h> 14 #include <linux/sched/hotplug.h> 15 #include <linux/sched/idle.h> 16 #include <linux/sched/init.h> 17 #include <linux/sched/isolation.h> 18 #include <linux/sched/jobctl.h> 19 #include <linux/sched/loadavg.h> 20 #include <linux/sched/mm.h> 21 #include <linux/sched/nohz.h> 22 #include <linux/sched/numa_balancing.h> 23 #include <linux/sched/prio.h> 24 #include <linux/sched/rt.h> 25 #include <linux/sched/signal.h> 26 #include <linux/sched/stat.h> 27 #include <linux/sched/sysctl.h> 28 #include <linux/sched/task.h> 29 #include <linux/sched/task_stack.h> 30 #include <linux/sched/topology.h> 31 #include <linux/sched/user.h> 32 #include <linux/sched/wake_q.h> 33 #include <linux/sched/xacct.h> 34 35 #include <uapi/linux/sched/types.h> 36 37 #include <linux/binfmts.h> 38 #include <linux/blkdev.h> 39 #include <linux/compat.h> 40 #include <linux/context_tracking.h> 41 #include <linux/cpufreq.h> 42 #include <linux/cpuidle.h> 43 #include <linux/cpuset.h> 44 #include <linux/ctype.h> 45 #include <linux/debugfs.h> 46 #include <linux/delayacct.h> 47 #include <linux/init_task.h> 48 #include <linux/kprobes.h> 49 #include <linux/kthread.h> 50 #include <linux/membarrier.h> 51 #include <linux/migrate.h> 52 #include <linux/mmu_context.h> 53 #include <linux/nmi.h> 54 #include <linux/proc_fs.h> 55 #include <linux/prefetch.h> 56 #include <linux/profile.h> 57 #include <linux/rcupdate_wait.h> 58 #include <linux/security.h> 59 #include <linux/stackprotector.h> 60 #include <linux/stop_machine.h> 61 #include <linux/suspend.h> 62 #include <linux/swait.h> 63 #include <linux/syscalls.h> 64 #include <linux/task_work.h> 65 #include <linux/tsacct_kern.h> 66 67 #include <asm/tlb.h> 68 69 #ifdef CONFIG_PARAVIRT 70 # include <asm/paravirt.h> 71 #endif 72 73 #include "cpupri.h" 74 #include "cpudeadline.h" 75 76 #ifdef CONFIG_SCHED_DEBUG 77 # define SCHED_WARN_ON(x) WARN_ONCE(x, #x) 78 #else 79 # define SCHED_WARN_ON(x) ({ (void)(x), 0; }) 80 #endif 81 82 struct rq; 83 struct cpuidle_state; 84 85 /* task_struct::on_rq states: */ 86 #define TASK_ON_RQ_QUEUED 1 87 #define TASK_ON_RQ_MIGRATING 2 88 89 extern __read_mostly int scheduler_running; 90 91 extern unsigned long calc_load_update; 92 extern atomic_long_t calc_load_tasks; 93 94 extern void calc_global_load_tick(struct rq *this_rq); 95 extern long calc_load_fold_active(struct rq *this_rq, long adjust); 96 97 #ifdef CONFIG_SMP 98 extern void cpu_load_update_active(struct rq *this_rq); 99 #else 100 static inline void cpu_load_update_active(struct rq *this_rq) { } 101 #endif 102 103 /* 104 * Helpers for converting nanosecond timing to jiffy resolution 105 */ 106 #define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ)) 107 108 /* 109 * Increase resolution of nice-level calculations for 64-bit architectures. 110 * The extra resolution improves shares distribution and load balancing of 111 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup 112 * hierarchies, especially on larger systems. This is not a user-visible change 113 * and does not change the user-interface for setting shares/weights. 114 * 115 * We increase resolution only if we have enough bits to allow this increased 116 * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit 117 * are pretty high and the returns do not justify the increased costs. 118 * 119 * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to 120 * increase coverage and consistency always enable it on 64-bit platforms. 121 */ 122 #ifdef CONFIG_64BIT 123 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT) 124 # define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT) 125 # define scale_load_down(w) ((w) >> SCHED_FIXEDPOINT_SHIFT) 126 #else 127 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT) 128 # define scale_load(w) (w) 129 # define scale_load_down(w) (w) 130 #endif 131 132 /* 133 * Task weight (visible to users) and its load (invisible to users) have 134 * independent resolution, but they should be well calibrated. We use 135 * scale_load() and scale_load_down(w) to convert between them. The 136 * following must be true: 137 * 138 * scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD 139 * 140 */ 141 #define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT) 142 143 /* 144 * Single value that decides SCHED_DEADLINE internal math precision. 145 * 10 -> just above 1us 146 * 9 -> just above 0.5us 147 */ 148 #define DL_SCALE 10 149 150 /* 151 * Single value that denotes runtime == period, ie unlimited time. 152 */ 153 #define RUNTIME_INF ((u64)~0ULL) 154 155 static inline int idle_policy(int policy) 156 { 157 return policy == SCHED_IDLE; 158 } 159 static inline int fair_policy(int policy) 160 { 161 return policy == SCHED_NORMAL || policy == SCHED_BATCH; 162 } 163 164 static inline int rt_policy(int policy) 165 { 166 return policy == SCHED_FIFO || policy == SCHED_RR; 167 } 168 169 static inline int dl_policy(int policy) 170 { 171 return policy == SCHED_DEADLINE; 172 } 173 static inline bool valid_policy(int policy) 174 { 175 return idle_policy(policy) || fair_policy(policy) || 176 rt_policy(policy) || dl_policy(policy); 177 } 178 179 static inline int task_has_rt_policy(struct task_struct *p) 180 { 181 return rt_policy(p->policy); 182 } 183 184 static inline int task_has_dl_policy(struct task_struct *p) 185 { 186 return dl_policy(p->policy); 187 } 188 189 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT) 190 191 /* 192 * !! For sched_setattr_nocheck() (kernel) only !! 193 * 194 * This is actually gross. :( 195 * 196 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE 197 * tasks, but still be able to sleep. We need this on platforms that cannot 198 * atomically change clock frequency. Remove once fast switching will be 199 * available on such platforms. 200 * 201 * SUGOV stands for SchedUtil GOVernor. 202 */ 203 #define SCHED_FLAG_SUGOV 0x10000000 204 205 static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se) 206 { 207 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL 208 return unlikely(dl_se->flags & SCHED_FLAG_SUGOV); 209 #else 210 return false; 211 #endif 212 } 213 214 /* 215 * Tells if entity @a should preempt entity @b. 216 */ 217 static inline bool 218 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b) 219 { 220 return dl_entity_is_special(a) || 221 dl_time_before(a->deadline, b->deadline); 222 } 223 224 /* 225 * This is the priority-queue data structure of the RT scheduling class: 226 */ 227 struct rt_prio_array { 228 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */ 229 struct list_head queue[MAX_RT_PRIO]; 230 }; 231 232 struct rt_bandwidth { 233 /* nests inside the rq lock: */ 234 raw_spinlock_t rt_runtime_lock; 235 ktime_t rt_period; 236 u64 rt_runtime; 237 struct hrtimer rt_period_timer; 238 unsigned int rt_period_active; 239 }; 240 241 void __dl_clear_params(struct task_struct *p); 242 243 /* 244 * To keep the bandwidth of -deadline tasks and groups under control 245 * we need some place where: 246 * - store the maximum -deadline bandwidth of the system (the group); 247 * - cache the fraction of that bandwidth that is currently allocated. 248 * 249 * This is all done in the data structure below. It is similar to the 250 * one used for RT-throttling (rt_bandwidth), with the main difference 251 * that, since here we are only interested in admission control, we 252 * do not decrease any runtime while the group "executes", neither we 253 * need a timer to replenish it. 254 * 255 * With respect to SMP, the bandwidth is given on a per-CPU basis, 256 * meaning that: 257 * - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU; 258 * - dl_total_bw array contains, in the i-eth element, the currently 259 * allocated bandwidth on the i-eth CPU. 260 * Moreover, groups consume bandwidth on each CPU, while tasks only 261 * consume bandwidth on the CPU they're running on. 262 * Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw 263 * that will be shown the next time the proc or cgroup controls will 264 * be red. It on its turn can be changed by writing on its own 265 * control. 266 */ 267 struct dl_bandwidth { 268 raw_spinlock_t dl_runtime_lock; 269 u64 dl_runtime; 270 u64 dl_period; 271 }; 272 273 static inline int dl_bandwidth_enabled(void) 274 { 275 return sysctl_sched_rt_runtime >= 0; 276 } 277 278 struct dl_bw { 279 raw_spinlock_t lock; 280 u64 bw; 281 u64 total_bw; 282 }; 283 284 static inline void __dl_update(struct dl_bw *dl_b, s64 bw); 285 286 static inline 287 void __dl_sub(struct dl_bw *dl_b, u64 tsk_bw, int cpus) 288 { 289 dl_b->total_bw -= tsk_bw; 290 __dl_update(dl_b, (s32)tsk_bw / cpus); 291 } 292 293 static inline 294 void __dl_add(struct dl_bw *dl_b, u64 tsk_bw, int cpus) 295 { 296 dl_b->total_bw += tsk_bw; 297 __dl_update(dl_b, -((s32)tsk_bw / cpus)); 298 } 299 300 static inline 301 bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw) 302 { 303 return dl_b->bw != -1 && 304 dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw; 305 } 306 307 extern void dl_change_utilization(struct task_struct *p, u64 new_bw); 308 extern void init_dl_bw(struct dl_bw *dl_b); 309 extern int sched_dl_global_validate(void); 310 extern void sched_dl_do_global(void); 311 extern int sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr); 312 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr); 313 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr); 314 extern bool __checkparam_dl(const struct sched_attr *attr); 315 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr); 316 extern int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed); 317 extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 318 extern bool dl_cpu_busy(unsigned int cpu); 319 320 #ifdef CONFIG_CGROUP_SCHED 321 322 #include <linux/cgroup.h> 323 324 struct cfs_rq; 325 struct rt_rq; 326 327 extern struct list_head task_groups; 328 329 struct cfs_bandwidth { 330 #ifdef CONFIG_CFS_BANDWIDTH 331 raw_spinlock_t lock; 332 ktime_t period; 333 u64 quota; 334 u64 runtime; 335 s64 hierarchical_quota; 336 u64 runtime_expires; 337 338 int idle; 339 int period_active; 340 struct hrtimer period_timer; 341 struct hrtimer slack_timer; 342 struct list_head throttled_cfs_rq; 343 344 /* Statistics: */ 345 int nr_periods; 346 int nr_throttled; 347 u64 throttled_time; 348 #endif 349 }; 350 351 /* Task group related information */ 352 struct task_group { 353 struct cgroup_subsys_state css; 354 355 #ifdef CONFIG_FAIR_GROUP_SCHED 356 /* schedulable entities of this group on each CPU */ 357 struct sched_entity **se; 358 /* runqueue "owned" by this group on each CPU */ 359 struct cfs_rq **cfs_rq; 360 unsigned long shares; 361 362 #ifdef CONFIG_SMP 363 /* 364 * load_avg can be heavily contended at clock tick time, so put 365 * it in its own cacheline separated from the fields above which 366 * will also be accessed at each tick. 367 */ 368 atomic_long_t load_avg ____cacheline_aligned; 369 #endif 370 #endif 371 372 #ifdef CONFIG_RT_GROUP_SCHED 373 struct sched_rt_entity **rt_se; 374 struct rt_rq **rt_rq; 375 376 struct rt_bandwidth rt_bandwidth; 377 #endif 378 379 struct rcu_head rcu; 380 struct list_head list; 381 382 struct task_group *parent; 383 struct list_head siblings; 384 struct list_head children; 385 386 #ifdef CONFIG_SCHED_AUTOGROUP 387 struct autogroup *autogroup; 388 #endif 389 390 struct cfs_bandwidth cfs_bandwidth; 391 }; 392 393 #ifdef CONFIG_FAIR_GROUP_SCHED 394 #define ROOT_TASK_GROUP_LOAD NICE_0_LOAD 395 396 /* 397 * A weight of 0 or 1 can cause arithmetics problems. 398 * A weight of a cfs_rq is the sum of weights of which entities 399 * are queued on this cfs_rq, so a weight of a entity should not be 400 * too large, so as the shares value of a task group. 401 * (The default weight is 1024 - so there's no practical 402 * limitation from this.) 403 */ 404 #define MIN_SHARES (1UL << 1) 405 #define MAX_SHARES (1UL << 18) 406 #endif 407 408 typedef int (*tg_visitor)(struct task_group *, void *); 409 410 extern int walk_tg_tree_from(struct task_group *from, 411 tg_visitor down, tg_visitor up, void *data); 412 413 /* 414 * Iterate the full tree, calling @down when first entering a node and @up when 415 * leaving it for the final time. 416 * 417 * Caller must hold rcu_lock or sufficient equivalent. 418 */ 419 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data) 420 { 421 return walk_tg_tree_from(&root_task_group, down, up, data); 422 } 423 424 extern int tg_nop(struct task_group *tg, void *data); 425 426 extern void free_fair_sched_group(struct task_group *tg); 427 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent); 428 extern void online_fair_sched_group(struct task_group *tg); 429 extern void unregister_fair_sched_group(struct task_group *tg); 430 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, 431 struct sched_entity *se, int cpu, 432 struct sched_entity *parent); 433 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b); 434 435 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b); 436 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b); 437 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq); 438 439 extern void free_rt_sched_group(struct task_group *tg); 440 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent); 441 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, 442 struct sched_rt_entity *rt_se, int cpu, 443 struct sched_rt_entity *parent); 444 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us); 445 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us); 446 extern long sched_group_rt_runtime(struct task_group *tg); 447 extern long sched_group_rt_period(struct task_group *tg); 448 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk); 449 450 extern struct task_group *sched_create_group(struct task_group *parent); 451 extern void sched_online_group(struct task_group *tg, 452 struct task_group *parent); 453 extern void sched_destroy_group(struct task_group *tg); 454 extern void sched_offline_group(struct task_group *tg); 455 456 extern void sched_move_task(struct task_struct *tsk); 457 458 #ifdef CONFIG_FAIR_GROUP_SCHED 459 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); 460 461 #ifdef CONFIG_SMP 462 extern void set_task_rq_fair(struct sched_entity *se, 463 struct cfs_rq *prev, struct cfs_rq *next); 464 #else /* !CONFIG_SMP */ 465 static inline void set_task_rq_fair(struct sched_entity *se, 466 struct cfs_rq *prev, struct cfs_rq *next) { } 467 #endif /* CONFIG_SMP */ 468 #endif /* CONFIG_FAIR_GROUP_SCHED */ 469 470 #else /* CONFIG_CGROUP_SCHED */ 471 472 struct cfs_bandwidth { }; 473 474 #endif /* CONFIG_CGROUP_SCHED */ 475 476 /* CFS-related fields in a runqueue */ 477 struct cfs_rq { 478 struct load_weight load; 479 unsigned long runnable_weight; 480 unsigned int nr_running; 481 unsigned int h_nr_running; 482 483 u64 exec_clock; 484 u64 min_vruntime; 485 #ifndef CONFIG_64BIT 486 u64 min_vruntime_copy; 487 #endif 488 489 struct rb_root_cached tasks_timeline; 490 491 /* 492 * 'curr' points to currently running entity on this cfs_rq. 493 * It is set to NULL otherwise (i.e when none are currently running). 494 */ 495 struct sched_entity *curr; 496 struct sched_entity *next; 497 struct sched_entity *last; 498 struct sched_entity *skip; 499 500 #ifdef CONFIG_SCHED_DEBUG 501 unsigned int nr_spread_over; 502 #endif 503 504 #ifdef CONFIG_SMP 505 /* 506 * CFS load tracking 507 */ 508 struct sched_avg avg; 509 #ifndef CONFIG_64BIT 510 u64 load_last_update_time_copy; 511 #endif 512 struct { 513 raw_spinlock_t lock ____cacheline_aligned; 514 int nr; 515 unsigned long load_avg; 516 unsigned long util_avg; 517 unsigned long runnable_sum; 518 } removed; 519 520 #ifdef CONFIG_FAIR_GROUP_SCHED 521 unsigned long tg_load_avg_contrib; 522 long propagate; 523 long prop_runnable_sum; 524 525 /* 526 * h_load = weight * f(tg) 527 * 528 * Where f(tg) is the recursive weight fraction assigned to 529 * this group. 530 */ 531 unsigned long h_load; 532 u64 last_h_load_update; 533 struct sched_entity *h_load_next; 534 #endif /* CONFIG_FAIR_GROUP_SCHED */ 535 #endif /* CONFIG_SMP */ 536 537 #ifdef CONFIG_FAIR_GROUP_SCHED 538 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */ 539 540 /* 541 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in 542 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities 543 * (like users, containers etc.) 544 * 545 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU. 546 * This list is used during load balance. 547 */ 548 int on_list; 549 struct list_head leaf_cfs_rq_list; 550 struct task_group *tg; /* group that "owns" this runqueue */ 551 552 #ifdef CONFIG_CFS_BANDWIDTH 553 int runtime_enabled; 554 u64 runtime_expires; 555 s64 runtime_remaining; 556 557 u64 throttled_clock; 558 u64 throttled_clock_task; 559 u64 throttled_clock_task_time; 560 int throttled; 561 int throttle_count; 562 struct list_head throttled_list; 563 #endif /* CONFIG_CFS_BANDWIDTH */ 564 #endif /* CONFIG_FAIR_GROUP_SCHED */ 565 }; 566 567 static inline int rt_bandwidth_enabled(void) 568 { 569 return sysctl_sched_rt_runtime >= 0; 570 } 571 572 /* RT IPI pull logic requires IRQ_WORK */ 573 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP) 574 # define HAVE_RT_PUSH_IPI 575 #endif 576 577 /* Real-Time classes' related field in a runqueue: */ 578 struct rt_rq { 579 struct rt_prio_array active; 580 unsigned int rt_nr_running; 581 unsigned int rr_nr_running; 582 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED 583 struct { 584 int curr; /* highest queued rt task prio */ 585 #ifdef CONFIG_SMP 586 int next; /* next highest */ 587 #endif 588 } highest_prio; 589 #endif 590 #ifdef CONFIG_SMP 591 unsigned long rt_nr_migratory; 592 unsigned long rt_nr_total; 593 int overloaded; 594 struct plist_head pushable_tasks; 595 #endif /* CONFIG_SMP */ 596 int rt_queued; 597 598 int rt_throttled; 599 u64 rt_time; 600 u64 rt_runtime; 601 /* Nests inside the rq lock: */ 602 raw_spinlock_t rt_runtime_lock; 603 604 #ifdef CONFIG_RT_GROUP_SCHED 605 unsigned long rt_nr_boosted; 606 607 struct rq *rq; 608 struct task_group *tg; 609 #endif 610 }; 611 612 /* Deadline class' related fields in a runqueue */ 613 struct dl_rq { 614 /* runqueue is an rbtree, ordered by deadline */ 615 struct rb_root_cached root; 616 617 unsigned long dl_nr_running; 618 619 #ifdef CONFIG_SMP 620 /* 621 * Deadline values of the currently executing and the 622 * earliest ready task on this rq. Caching these facilitates 623 * the decision wether or not a ready but not running task 624 * should migrate somewhere else. 625 */ 626 struct { 627 u64 curr; 628 u64 next; 629 } earliest_dl; 630 631 unsigned long dl_nr_migratory; 632 int overloaded; 633 634 /* 635 * Tasks on this rq that can be pushed away. They are kept in 636 * an rb-tree, ordered by tasks' deadlines, with caching 637 * of the leftmost (earliest deadline) element. 638 */ 639 struct rb_root_cached pushable_dl_tasks_root; 640 #else 641 struct dl_bw dl_bw; 642 #endif 643 /* 644 * "Active utilization" for this runqueue: increased when a 645 * task wakes up (becomes TASK_RUNNING) and decreased when a 646 * task blocks 647 */ 648 u64 running_bw; 649 650 /* 651 * Utilization of the tasks "assigned" to this runqueue (including 652 * the tasks that are in runqueue and the tasks that executed on this 653 * CPU and blocked). Increased when a task moves to this runqueue, and 654 * decreased when the task moves away (migrates, changes scheduling 655 * policy, or terminates). 656 * This is needed to compute the "inactive utilization" for the 657 * runqueue (inactive utilization = this_bw - running_bw). 658 */ 659 u64 this_bw; 660 u64 extra_bw; 661 662 /* 663 * Inverse of the fraction of CPU utilization that can be reclaimed 664 * by the GRUB algorithm. 665 */ 666 u64 bw_ratio; 667 }; 668 669 #ifdef CONFIG_SMP 670 671 static inline bool sched_asym_prefer(int a, int b) 672 { 673 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b); 674 } 675 676 /* 677 * We add the notion of a root-domain which will be used to define per-domain 678 * variables. Each exclusive cpuset essentially defines an island domain by 679 * fully partitioning the member CPUs from any other cpuset. Whenever a new 680 * exclusive cpuset is created, we also create and attach a new root-domain 681 * object. 682 * 683 */ 684 struct root_domain { 685 atomic_t refcount; 686 atomic_t rto_count; 687 struct rcu_head rcu; 688 cpumask_var_t span; 689 cpumask_var_t online; 690 691 /* Indicate more than one runnable task for any CPU */ 692 bool overload; 693 694 /* 695 * The bit corresponding to a CPU gets set here if such CPU has more 696 * than one runnable -deadline task (as it is below for RT tasks). 697 */ 698 cpumask_var_t dlo_mask; 699 atomic_t dlo_count; 700 struct dl_bw dl_bw; 701 struct cpudl cpudl; 702 703 #ifdef HAVE_RT_PUSH_IPI 704 /* 705 * For IPI pull requests, loop across the rto_mask. 706 */ 707 struct irq_work rto_push_work; 708 raw_spinlock_t rto_lock; 709 /* These are only updated and read within rto_lock */ 710 int rto_loop; 711 int rto_cpu; 712 /* These atomics are updated outside of a lock */ 713 atomic_t rto_loop_next; 714 atomic_t rto_loop_start; 715 #endif 716 /* 717 * The "RT overload" flag: it gets set if a CPU has more than 718 * one runnable RT task. 719 */ 720 cpumask_var_t rto_mask; 721 struct cpupri cpupri; 722 723 unsigned long max_cpu_capacity; 724 }; 725 726 extern struct root_domain def_root_domain; 727 extern struct mutex sched_domains_mutex; 728 729 extern void init_defrootdomain(void); 730 extern int sched_init_domains(const struct cpumask *cpu_map); 731 extern void rq_attach_root(struct rq *rq, struct root_domain *rd); 732 extern void sched_get_rd(struct root_domain *rd); 733 extern void sched_put_rd(struct root_domain *rd); 734 735 #ifdef HAVE_RT_PUSH_IPI 736 extern void rto_push_irq_work_func(struct irq_work *work); 737 #endif 738 #endif /* CONFIG_SMP */ 739 740 /* 741 * This is the main, per-CPU runqueue data structure. 742 * 743 * Locking rule: those places that want to lock multiple runqueues 744 * (such as the load balancing or the thread migration code), lock 745 * acquire operations must be ordered by ascending &runqueue. 746 */ 747 struct rq { 748 /* runqueue lock: */ 749 raw_spinlock_t lock; 750 751 /* 752 * nr_running and cpu_load should be in the same cacheline because 753 * remote CPUs use both these fields when doing load calculation. 754 */ 755 unsigned int nr_running; 756 #ifdef CONFIG_NUMA_BALANCING 757 unsigned int nr_numa_running; 758 unsigned int nr_preferred_running; 759 #endif 760 #define CPU_LOAD_IDX_MAX 5 761 unsigned long cpu_load[CPU_LOAD_IDX_MAX]; 762 #ifdef CONFIG_NO_HZ_COMMON 763 #ifdef CONFIG_SMP 764 unsigned long last_load_update_tick; 765 unsigned long last_blocked_load_update_tick; 766 unsigned int has_blocked_load; 767 #endif /* CONFIG_SMP */ 768 unsigned int nohz_tick_stopped; 769 atomic_t nohz_flags; 770 #endif /* CONFIG_NO_HZ_COMMON */ 771 772 /* capture load from *all* tasks on this CPU: */ 773 struct load_weight load; 774 unsigned long nr_load_updates; 775 u64 nr_switches; 776 777 struct cfs_rq cfs; 778 struct rt_rq rt; 779 struct dl_rq dl; 780 781 #ifdef CONFIG_FAIR_GROUP_SCHED 782 /* list of leaf cfs_rq on this CPU: */ 783 struct list_head leaf_cfs_rq_list; 784 struct list_head *tmp_alone_branch; 785 #endif /* CONFIG_FAIR_GROUP_SCHED */ 786 787 /* 788 * This is part of a global counter where only the total sum 789 * over all CPUs matters. A task can increase this counter on 790 * one CPU and if it got migrated afterwards it may decrease 791 * it on another CPU. Always updated under the runqueue lock: 792 */ 793 unsigned long nr_uninterruptible; 794 795 struct task_struct *curr; 796 struct task_struct *idle; 797 struct task_struct *stop; 798 unsigned long next_balance; 799 struct mm_struct *prev_mm; 800 801 unsigned int clock_update_flags; 802 u64 clock; 803 u64 clock_task; 804 805 atomic_t nr_iowait; 806 807 #ifdef CONFIG_SMP 808 struct root_domain *rd; 809 struct sched_domain *sd; 810 811 unsigned long cpu_capacity; 812 unsigned long cpu_capacity_orig; 813 814 struct callback_head *balance_callback; 815 816 unsigned char idle_balance; 817 818 /* For active balancing */ 819 int active_balance; 820 int push_cpu; 821 struct cpu_stop_work active_balance_work; 822 823 /* CPU of this runqueue: */ 824 int cpu; 825 int online; 826 827 struct list_head cfs_tasks; 828 829 u64 rt_avg; 830 u64 age_stamp; 831 u64 idle_stamp; 832 u64 avg_idle; 833 834 /* This is used to determine avg_idle's max value */ 835 u64 max_idle_balance_cost; 836 #endif 837 838 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 839 u64 prev_irq_time; 840 #endif 841 #ifdef CONFIG_PARAVIRT 842 u64 prev_steal_time; 843 #endif 844 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING 845 u64 prev_steal_time_rq; 846 #endif 847 848 /* calc_load related fields */ 849 unsigned long calc_load_update; 850 long calc_load_active; 851 852 #ifdef CONFIG_SCHED_HRTICK 853 #ifdef CONFIG_SMP 854 int hrtick_csd_pending; 855 call_single_data_t hrtick_csd; 856 #endif 857 struct hrtimer hrtick_timer; 858 #endif 859 860 #ifdef CONFIG_SCHEDSTATS 861 /* latency stats */ 862 struct sched_info rq_sched_info; 863 unsigned long long rq_cpu_time; 864 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */ 865 866 /* sys_sched_yield() stats */ 867 unsigned int yld_count; 868 869 /* schedule() stats */ 870 unsigned int sched_count; 871 unsigned int sched_goidle; 872 873 /* try_to_wake_up() stats */ 874 unsigned int ttwu_count; 875 unsigned int ttwu_local; 876 #endif 877 878 #ifdef CONFIG_SMP 879 struct llist_head wake_list; 880 #endif 881 882 #ifdef CONFIG_CPU_IDLE 883 /* Must be inspected within a rcu lock section */ 884 struct cpuidle_state *idle_state; 885 #endif 886 }; 887 888 static inline int cpu_of(struct rq *rq) 889 { 890 #ifdef CONFIG_SMP 891 return rq->cpu; 892 #else 893 return 0; 894 #endif 895 } 896 897 898 #ifdef CONFIG_SCHED_SMT 899 900 extern struct static_key_false sched_smt_present; 901 902 extern void __update_idle_core(struct rq *rq); 903 904 static inline void update_idle_core(struct rq *rq) 905 { 906 if (static_branch_unlikely(&sched_smt_present)) 907 __update_idle_core(rq); 908 } 909 910 #else 911 static inline void update_idle_core(struct rq *rq) { } 912 #endif 913 914 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); 915 916 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) 917 #define this_rq() this_cpu_ptr(&runqueues) 918 #define task_rq(p) cpu_rq(task_cpu(p)) 919 #define cpu_curr(cpu) (cpu_rq(cpu)->curr) 920 #define raw_rq() raw_cpu_ptr(&runqueues) 921 922 static inline u64 __rq_clock_broken(struct rq *rq) 923 { 924 return READ_ONCE(rq->clock); 925 } 926 927 /* 928 * rq::clock_update_flags bits 929 * 930 * %RQCF_REQ_SKIP - will request skipping of clock update on the next 931 * call to __schedule(). This is an optimisation to avoid 932 * neighbouring rq clock updates. 933 * 934 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is 935 * in effect and calls to update_rq_clock() are being ignored. 936 * 937 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been 938 * made to update_rq_clock() since the last time rq::lock was pinned. 939 * 940 * If inside of __schedule(), clock_update_flags will have been 941 * shifted left (a left shift is a cheap operation for the fast path 942 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use, 943 * 944 * if (rq-clock_update_flags >= RQCF_UPDATED) 945 * 946 * to check if %RQCF_UPADTED is set. It'll never be shifted more than 947 * one position though, because the next rq_unpin_lock() will shift it 948 * back. 949 */ 950 #define RQCF_REQ_SKIP 0x01 951 #define RQCF_ACT_SKIP 0x02 952 #define RQCF_UPDATED 0x04 953 954 static inline void assert_clock_updated(struct rq *rq) 955 { 956 /* 957 * The only reason for not seeing a clock update since the 958 * last rq_pin_lock() is if we're currently skipping updates. 959 */ 960 SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP); 961 } 962 963 static inline u64 rq_clock(struct rq *rq) 964 { 965 lockdep_assert_held(&rq->lock); 966 assert_clock_updated(rq); 967 968 return rq->clock; 969 } 970 971 static inline u64 rq_clock_task(struct rq *rq) 972 { 973 lockdep_assert_held(&rq->lock); 974 assert_clock_updated(rq); 975 976 return rq->clock_task; 977 } 978 979 static inline void rq_clock_skip_update(struct rq *rq) 980 { 981 lockdep_assert_held(&rq->lock); 982 rq->clock_update_flags |= RQCF_REQ_SKIP; 983 } 984 985 /* 986 * See rt task throttoling, which is the only time a skip 987 * request is cancelled. 988 */ 989 static inline void rq_clock_cancel_skipupdate(struct rq *rq) 990 { 991 lockdep_assert_held(&rq->lock); 992 rq->clock_update_flags &= ~RQCF_REQ_SKIP; 993 } 994 995 struct rq_flags { 996 unsigned long flags; 997 struct pin_cookie cookie; 998 #ifdef CONFIG_SCHED_DEBUG 999 /* 1000 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the 1001 * current pin context is stashed here in case it needs to be 1002 * restored in rq_repin_lock(). 1003 */ 1004 unsigned int clock_update_flags; 1005 #endif 1006 }; 1007 1008 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf) 1009 { 1010 rf->cookie = lockdep_pin_lock(&rq->lock); 1011 1012 #ifdef CONFIG_SCHED_DEBUG 1013 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 1014 rf->clock_update_flags = 0; 1015 #endif 1016 } 1017 1018 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf) 1019 { 1020 #ifdef CONFIG_SCHED_DEBUG 1021 if (rq->clock_update_flags > RQCF_ACT_SKIP) 1022 rf->clock_update_flags = RQCF_UPDATED; 1023 #endif 1024 1025 lockdep_unpin_lock(&rq->lock, rf->cookie); 1026 } 1027 1028 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf) 1029 { 1030 lockdep_repin_lock(&rq->lock, rf->cookie); 1031 1032 #ifdef CONFIG_SCHED_DEBUG 1033 /* 1034 * Restore the value we stashed in @rf for this pin context. 1035 */ 1036 rq->clock_update_flags |= rf->clock_update_flags; 1037 #endif 1038 } 1039 1040 #ifdef CONFIG_NUMA 1041 enum numa_topology_type { 1042 NUMA_DIRECT, 1043 NUMA_GLUELESS_MESH, 1044 NUMA_BACKPLANE, 1045 }; 1046 extern enum numa_topology_type sched_numa_topology_type; 1047 extern int sched_max_numa_distance; 1048 extern bool find_numa_distance(int distance); 1049 #endif 1050 1051 #ifdef CONFIG_NUMA 1052 extern void sched_init_numa(void); 1053 extern void sched_domains_numa_masks_set(unsigned int cpu); 1054 extern void sched_domains_numa_masks_clear(unsigned int cpu); 1055 #else 1056 static inline void sched_init_numa(void) { } 1057 static inline void sched_domains_numa_masks_set(unsigned int cpu) { } 1058 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { } 1059 #endif 1060 1061 #ifdef CONFIG_NUMA_BALANCING 1062 /* The regions in numa_faults array from task_struct */ 1063 enum numa_faults_stats { 1064 NUMA_MEM = 0, 1065 NUMA_CPU, 1066 NUMA_MEMBUF, 1067 NUMA_CPUBUF 1068 }; 1069 extern void sched_setnuma(struct task_struct *p, int node); 1070 extern int migrate_task_to(struct task_struct *p, int cpu); 1071 extern int migrate_swap(struct task_struct *, struct task_struct *); 1072 #endif /* CONFIG_NUMA_BALANCING */ 1073 1074 #ifdef CONFIG_SMP 1075 1076 static inline void 1077 queue_balance_callback(struct rq *rq, 1078 struct callback_head *head, 1079 void (*func)(struct rq *rq)) 1080 { 1081 lockdep_assert_held(&rq->lock); 1082 1083 if (unlikely(head->next)) 1084 return; 1085 1086 head->func = (void (*)(struct callback_head *))func; 1087 head->next = rq->balance_callback; 1088 rq->balance_callback = head; 1089 } 1090 1091 extern void sched_ttwu_pending(void); 1092 1093 #define rcu_dereference_check_sched_domain(p) \ 1094 rcu_dereference_check((p), \ 1095 lockdep_is_held(&sched_domains_mutex)) 1096 1097 /* 1098 * The domain tree (rq->sd) is protected by RCU's quiescent state transition. 1099 * See detach_destroy_domains: synchronize_sched for details. 1100 * 1101 * The domain tree of any CPU may only be accessed from within 1102 * preempt-disabled sections. 1103 */ 1104 #define for_each_domain(cpu, __sd) \ 1105 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \ 1106 __sd; __sd = __sd->parent) 1107 1108 #define for_each_lower_domain(sd) for (; sd; sd = sd->child) 1109 1110 /** 1111 * highest_flag_domain - Return highest sched_domain containing flag. 1112 * @cpu: The CPU whose highest level of sched domain is to 1113 * be returned. 1114 * @flag: The flag to check for the highest sched_domain 1115 * for the given CPU. 1116 * 1117 * Returns the highest sched_domain of a CPU which contains the given flag. 1118 */ 1119 static inline struct sched_domain *highest_flag_domain(int cpu, int flag) 1120 { 1121 struct sched_domain *sd, *hsd = NULL; 1122 1123 for_each_domain(cpu, sd) { 1124 if (!(sd->flags & flag)) 1125 break; 1126 hsd = sd; 1127 } 1128 1129 return hsd; 1130 } 1131 1132 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) 1133 { 1134 struct sched_domain *sd; 1135 1136 for_each_domain(cpu, sd) { 1137 if (sd->flags & flag) 1138 break; 1139 } 1140 1141 return sd; 1142 } 1143 1144 DECLARE_PER_CPU(struct sched_domain *, sd_llc); 1145 DECLARE_PER_CPU(int, sd_llc_size); 1146 DECLARE_PER_CPU(int, sd_llc_id); 1147 DECLARE_PER_CPU(struct sched_domain_shared *, sd_llc_shared); 1148 DECLARE_PER_CPU(struct sched_domain *, sd_numa); 1149 DECLARE_PER_CPU(struct sched_domain *, sd_asym); 1150 1151 struct sched_group_capacity { 1152 atomic_t ref; 1153 /* 1154 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity 1155 * for a single CPU. 1156 */ 1157 unsigned long capacity; 1158 unsigned long min_capacity; /* Min per-CPU capacity in group */ 1159 unsigned long next_update; 1160 int imbalance; /* XXX unrelated to capacity but shared group state */ 1161 1162 #ifdef CONFIG_SCHED_DEBUG 1163 int id; 1164 #endif 1165 1166 unsigned long cpumask[0]; /* Balance mask */ 1167 }; 1168 1169 struct sched_group { 1170 struct sched_group *next; /* Must be a circular list */ 1171 atomic_t ref; 1172 1173 unsigned int group_weight; 1174 struct sched_group_capacity *sgc; 1175 int asym_prefer_cpu; /* CPU of highest priority in group */ 1176 1177 /* 1178 * The CPUs this group covers. 1179 * 1180 * NOTE: this field is variable length. (Allocated dynamically 1181 * by attaching extra space to the end of the structure, 1182 * depending on how many CPUs the kernel has booted up with) 1183 */ 1184 unsigned long cpumask[0]; 1185 }; 1186 1187 static inline struct cpumask *sched_group_span(struct sched_group *sg) 1188 { 1189 return to_cpumask(sg->cpumask); 1190 } 1191 1192 /* 1193 * See build_balance_mask(). 1194 */ 1195 static inline struct cpumask *group_balance_mask(struct sched_group *sg) 1196 { 1197 return to_cpumask(sg->sgc->cpumask); 1198 } 1199 1200 /** 1201 * group_first_cpu - Returns the first CPU in the cpumask of a sched_group. 1202 * @group: The group whose first CPU is to be returned. 1203 */ 1204 static inline unsigned int group_first_cpu(struct sched_group *group) 1205 { 1206 return cpumask_first(sched_group_span(group)); 1207 } 1208 1209 extern int group_balance_cpu(struct sched_group *sg); 1210 1211 #if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL) 1212 void register_sched_domain_sysctl(void); 1213 void dirty_sched_domain_sysctl(int cpu); 1214 void unregister_sched_domain_sysctl(void); 1215 #else 1216 static inline void register_sched_domain_sysctl(void) 1217 { 1218 } 1219 static inline void dirty_sched_domain_sysctl(int cpu) 1220 { 1221 } 1222 static inline void unregister_sched_domain_sysctl(void) 1223 { 1224 } 1225 #endif 1226 1227 #else 1228 1229 static inline void sched_ttwu_pending(void) { } 1230 1231 #endif /* CONFIG_SMP */ 1232 1233 #include "stats.h" 1234 #include "autogroup.h" 1235 1236 #ifdef CONFIG_CGROUP_SCHED 1237 1238 /* 1239 * Return the group to which this tasks belongs. 1240 * 1241 * We cannot use task_css() and friends because the cgroup subsystem 1242 * changes that value before the cgroup_subsys::attach() method is called, 1243 * therefore we cannot pin it and might observe the wrong value. 1244 * 1245 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup 1246 * core changes this before calling sched_move_task(). 1247 * 1248 * Instead we use a 'copy' which is updated from sched_move_task() while 1249 * holding both task_struct::pi_lock and rq::lock. 1250 */ 1251 static inline struct task_group *task_group(struct task_struct *p) 1252 { 1253 return p->sched_task_group; 1254 } 1255 1256 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ 1257 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) 1258 { 1259 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED) 1260 struct task_group *tg = task_group(p); 1261 #endif 1262 1263 #ifdef CONFIG_FAIR_GROUP_SCHED 1264 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]); 1265 p->se.cfs_rq = tg->cfs_rq[cpu]; 1266 p->se.parent = tg->se[cpu]; 1267 #endif 1268 1269 #ifdef CONFIG_RT_GROUP_SCHED 1270 p->rt.rt_rq = tg->rt_rq[cpu]; 1271 p->rt.parent = tg->rt_se[cpu]; 1272 #endif 1273 } 1274 1275 #else /* CONFIG_CGROUP_SCHED */ 1276 1277 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } 1278 static inline struct task_group *task_group(struct task_struct *p) 1279 { 1280 return NULL; 1281 } 1282 1283 #endif /* CONFIG_CGROUP_SCHED */ 1284 1285 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) 1286 { 1287 set_task_rq(p, cpu); 1288 #ifdef CONFIG_SMP 1289 /* 1290 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be 1291 * successfuly executed on another CPU. We must ensure that updates of 1292 * per-task data have been completed by this moment. 1293 */ 1294 smp_wmb(); 1295 #ifdef CONFIG_THREAD_INFO_IN_TASK 1296 p->cpu = cpu; 1297 #else 1298 task_thread_info(p)->cpu = cpu; 1299 #endif 1300 p->wake_cpu = cpu; 1301 #endif 1302 } 1303 1304 /* 1305 * Tunables that become constants when CONFIG_SCHED_DEBUG is off: 1306 */ 1307 #ifdef CONFIG_SCHED_DEBUG 1308 # include <linux/static_key.h> 1309 # define const_debug __read_mostly 1310 #else 1311 # define const_debug const 1312 #endif 1313 1314 #define SCHED_FEAT(name, enabled) \ 1315 __SCHED_FEAT_##name , 1316 1317 enum { 1318 #include "features.h" 1319 __SCHED_FEAT_NR, 1320 }; 1321 1322 #undef SCHED_FEAT 1323 1324 #if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL) 1325 1326 /* 1327 * To support run-time toggling of sched features, all the translation units 1328 * (but core.c) reference the sysctl_sched_features defined in core.c. 1329 */ 1330 extern const_debug unsigned int sysctl_sched_features; 1331 1332 #define SCHED_FEAT(name, enabled) \ 1333 static __always_inline bool static_branch_##name(struct static_key *key) \ 1334 { \ 1335 return static_key_##enabled(key); \ 1336 } 1337 1338 #include "features.h" 1339 #undef SCHED_FEAT 1340 1341 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR]; 1342 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x])) 1343 1344 #else /* !(SCHED_DEBUG && HAVE_JUMP_LABEL) */ 1345 1346 /* 1347 * Each translation unit has its own copy of sysctl_sched_features to allow 1348 * constants propagation at compile time and compiler optimization based on 1349 * features default. 1350 */ 1351 #define SCHED_FEAT(name, enabled) \ 1352 (1UL << __SCHED_FEAT_##name) * enabled | 1353 static const_debug __maybe_unused unsigned int sysctl_sched_features = 1354 #include "features.h" 1355 0; 1356 #undef SCHED_FEAT 1357 1358 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) 1359 1360 #endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */ 1361 1362 extern struct static_key_false sched_numa_balancing; 1363 extern struct static_key_false sched_schedstats; 1364 1365 static inline u64 global_rt_period(void) 1366 { 1367 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC; 1368 } 1369 1370 static inline u64 global_rt_runtime(void) 1371 { 1372 if (sysctl_sched_rt_runtime < 0) 1373 return RUNTIME_INF; 1374 1375 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC; 1376 } 1377 1378 static inline int task_current(struct rq *rq, struct task_struct *p) 1379 { 1380 return rq->curr == p; 1381 } 1382 1383 static inline int task_running(struct rq *rq, struct task_struct *p) 1384 { 1385 #ifdef CONFIG_SMP 1386 return p->on_cpu; 1387 #else 1388 return task_current(rq, p); 1389 #endif 1390 } 1391 1392 static inline int task_on_rq_queued(struct task_struct *p) 1393 { 1394 return p->on_rq == TASK_ON_RQ_QUEUED; 1395 } 1396 1397 static inline int task_on_rq_migrating(struct task_struct *p) 1398 { 1399 return p->on_rq == TASK_ON_RQ_MIGRATING; 1400 } 1401 1402 /* 1403 * wake flags 1404 */ 1405 #define WF_SYNC 0x01 /* Waker goes to sleep after wakeup */ 1406 #define WF_FORK 0x02 /* Child wakeup after fork */ 1407 #define WF_MIGRATED 0x4 /* Internal use, task got migrated */ 1408 1409 /* 1410 * To aid in avoiding the subversion of "niceness" due to uneven distribution 1411 * of tasks with abnormal "nice" values across CPUs the contribution that 1412 * each task makes to its run queue's load is weighted according to its 1413 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a 1414 * scaled version of the new time slice allocation that they receive on time 1415 * slice expiry etc. 1416 */ 1417 1418 #define WEIGHT_IDLEPRIO 3 1419 #define WMULT_IDLEPRIO 1431655765 1420 1421 extern const int sched_prio_to_weight[40]; 1422 extern const u32 sched_prio_to_wmult[40]; 1423 1424 /* 1425 * {de,en}queue flags: 1426 * 1427 * DEQUEUE_SLEEP - task is no longer runnable 1428 * ENQUEUE_WAKEUP - task just became runnable 1429 * 1430 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks 1431 * are in a known state which allows modification. Such pairs 1432 * should preserve as much state as possible. 1433 * 1434 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location 1435 * in the runqueue. 1436 * 1437 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified) 1438 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline) 1439 * ENQUEUE_MIGRATED - the task was migrated during wakeup 1440 * 1441 */ 1442 1443 #define DEQUEUE_SLEEP 0x01 1444 #define DEQUEUE_SAVE 0x02 /* Matches ENQUEUE_RESTORE */ 1445 #define DEQUEUE_MOVE 0x04 /* Matches ENQUEUE_MOVE */ 1446 #define DEQUEUE_NOCLOCK 0x08 /* Matches ENQUEUE_NOCLOCK */ 1447 1448 #define ENQUEUE_WAKEUP 0x01 1449 #define ENQUEUE_RESTORE 0x02 1450 #define ENQUEUE_MOVE 0x04 1451 #define ENQUEUE_NOCLOCK 0x08 1452 1453 #define ENQUEUE_HEAD 0x10 1454 #define ENQUEUE_REPLENISH 0x20 1455 #ifdef CONFIG_SMP 1456 #define ENQUEUE_MIGRATED 0x40 1457 #else 1458 #define ENQUEUE_MIGRATED 0x00 1459 #endif 1460 1461 #define RETRY_TASK ((void *)-1UL) 1462 1463 struct sched_class { 1464 const struct sched_class *next; 1465 1466 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags); 1467 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags); 1468 void (*yield_task) (struct rq *rq); 1469 bool (*yield_to_task)(struct rq *rq, struct task_struct *p, bool preempt); 1470 1471 void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags); 1472 1473 /* 1474 * It is the responsibility of the pick_next_task() method that will 1475 * return the next task to call put_prev_task() on the @prev task or 1476 * something equivalent. 1477 * 1478 * May return RETRY_TASK when it finds a higher prio class has runnable 1479 * tasks. 1480 */ 1481 struct task_struct * (*pick_next_task)(struct rq *rq, 1482 struct task_struct *prev, 1483 struct rq_flags *rf); 1484 void (*put_prev_task)(struct rq *rq, struct task_struct *p); 1485 1486 #ifdef CONFIG_SMP 1487 int (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags); 1488 void (*migrate_task_rq)(struct task_struct *p); 1489 1490 void (*task_woken)(struct rq *this_rq, struct task_struct *task); 1491 1492 void (*set_cpus_allowed)(struct task_struct *p, 1493 const struct cpumask *newmask); 1494 1495 void (*rq_online)(struct rq *rq); 1496 void (*rq_offline)(struct rq *rq); 1497 #endif 1498 1499 void (*set_curr_task)(struct rq *rq); 1500 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued); 1501 void (*task_fork)(struct task_struct *p); 1502 void (*task_dead)(struct task_struct *p); 1503 1504 /* 1505 * The switched_from() call is allowed to drop rq->lock, therefore we 1506 * cannot assume the switched_from/switched_to pair is serliazed by 1507 * rq->lock. They are however serialized by p->pi_lock. 1508 */ 1509 void (*switched_from)(struct rq *this_rq, struct task_struct *task); 1510 void (*switched_to) (struct rq *this_rq, struct task_struct *task); 1511 void (*prio_changed) (struct rq *this_rq, struct task_struct *task, 1512 int oldprio); 1513 1514 unsigned int (*get_rr_interval)(struct rq *rq, 1515 struct task_struct *task); 1516 1517 void (*update_curr)(struct rq *rq); 1518 1519 #define TASK_SET_GROUP 0 1520 #define TASK_MOVE_GROUP 1 1521 1522 #ifdef CONFIG_FAIR_GROUP_SCHED 1523 void (*task_change_group)(struct task_struct *p, int type); 1524 #endif 1525 }; 1526 1527 static inline void put_prev_task(struct rq *rq, struct task_struct *prev) 1528 { 1529 prev->sched_class->put_prev_task(rq, prev); 1530 } 1531 1532 static inline void set_curr_task(struct rq *rq, struct task_struct *curr) 1533 { 1534 curr->sched_class->set_curr_task(rq); 1535 } 1536 1537 #ifdef CONFIG_SMP 1538 #define sched_class_highest (&stop_sched_class) 1539 #else 1540 #define sched_class_highest (&dl_sched_class) 1541 #endif 1542 #define for_each_class(class) \ 1543 for (class = sched_class_highest; class; class = class->next) 1544 1545 extern const struct sched_class stop_sched_class; 1546 extern const struct sched_class dl_sched_class; 1547 extern const struct sched_class rt_sched_class; 1548 extern const struct sched_class fair_sched_class; 1549 extern const struct sched_class idle_sched_class; 1550 1551 1552 #ifdef CONFIG_SMP 1553 1554 extern void update_group_capacity(struct sched_domain *sd, int cpu); 1555 1556 extern void trigger_load_balance(struct rq *rq); 1557 1558 extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask); 1559 1560 #endif 1561 1562 #ifdef CONFIG_CPU_IDLE 1563 static inline void idle_set_state(struct rq *rq, 1564 struct cpuidle_state *idle_state) 1565 { 1566 rq->idle_state = idle_state; 1567 } 1568 1569 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 1570 { 1571 SCHED_WARN_ON(!rcu_read_lock_held()); 1572 1573 return rq->idle_state; 1574 } 1575 #else 1576 static inline void idle_set_state(struct rq *rq, 1577 struct cpuidle_state *idle_state) 1578 { 1579 } 1580 1581 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 1582 { 1583 return NULL; 1584 } 1585 #endif 1586 1587 extern void schedule_idle(void); 1588 1589 extern void sysrq_sched_debug_show(void); 1590 extern void sched_init_granularity(void); 1591 extern void update_max_interval(void); 1592 1593 extern void init_sched_dl_class(void); 1594 extern void init_sched_rt_class(void); 1595 extern void init_sched_fair_class(void); 1596 1597 extern void reweight_task(struct task_struct *p, int prio); 1598 1599 extern void resched_curr(struct rq *rq); 1600 extern void resched_cpu(int cpu); 1601 1602 extern struct rt_bandwidth def_rt_bandwidth; 1603 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime); 1604 1605 extern struct dl_bandwidth def_dl_bandwidth; 1606 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime); 1607 extern void init_dl_task_timer(struct sched_dl_entity *dl_se); 1608 extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se); 1609 extern void init_dl_rq_bw_ratio(struct dl_rq *dl_rq); 1610 1611 #define BW_SHIFT 20 1612 #define BW_UNIT (1 << BW_SHIFT) 1613 #define RATIO_SHIFT 8 1614 unsigned long to_ratio(u64 period, u64 runtime); 1615 1616 extern void init_entity_runnable_average(struct sched_entity *se); 1617 extern void post_init_entity_util_avg(struct sched_entity *se); 1618 1619 #ifdef CONFIG_NO_HZ_FULL 1620 extern bool sched_can_stop_tick(struct rq *rq); 1621 extern int __init sched_tick_offload_init(void); 1622 1623 /* 1624 * Tick may be needed by tasks in the runqueue depending on their policy and 1625 * requirements. If tick is needed, lets send the target an IPI to kick it out of 1626 * nohz mode if necessary. 1627 */ 1628 static inline void sched_update_tick_dependency(struct rq *rq) 1629 { 1630 int cpu; 1631 1632 if (!tick_nohz_full_enabled()) 1633 return; 1634 1635 cpu = cpu_of(rq); 1636 1637 if (!tick_nohz_full_cpu(cpu)) 1638 return; 1639 1640 if (sched_can_stop_tick(rq)) 1641 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED); 1642 else 1643 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED); 1644 } 1645 #else 1646 static inline int sched_tick_offload_init(void) { return 0; } 1647 static inline void sched_update_tick_dependency(struct rq *rq) { } 1648 #endif 1649 1650 static inline void add_nr_running(struct rq *rq, unsigned count) 1651 { 1652 unsigned prev_nr = rq->nr_running; 1653 1654 rq->nr_running = prev_nr + count; 1655 1656 if (prev_nr < 2 && rq->nr_running >= 2) { 1657 #ifdef CONFIG_SMP 1658 if (!rq->rd->overload) 1659 rq->rd->overload = true; 1660 #endif 1661 } 1662 1663 sched_update_tick_dependency(rq); 1664 } 1665 1666 static inline void sub_nr_running(struct rq *rq, unsigned count) 1667 { 1668 rq->nr_running -= count; 1669 /* Check if we still need preemption */ 1670 sched_update_tick_dependency(rq); 1671 } 1672 1673 extern void update_rq_clock(struct rq *rq); 1674 1675 extern void activate_task(struct rq *rq, struct task_struct *p, int flags); 1676 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags); 1677 1678 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags); 1679 1680 extern const_debug unsigned int sysctl_sched_time_avg; 1681 extern const_debug unsigned int sysctl_sched_nr_migrate; 1682 extern const_debug unsigned int sysctl_sched_migration_cost; 1683 1684 static inline u64 sched_avg_period(void) 1685 { 1686 return (u64)sysctl_sched_time_avg * NSEC_PER_MSEC / 2; 1687 } 1688 1689 #ifdef CONFIG_SCHED_HRTICK 1690 1691 /* 1692 * Use hrtick when: 1693 * - enabled by features 1694 * - hrtimer is actually high res 1695 */ 1696 static inline int hrtick_enabled(struct rq *rq) 1697 { 1698 if (!sched_feat(HRTICK)) 1699 return 0; 1700 if (!cpu_active(cpu_of(rq))) 1701 return 0; 1702 return hrtimer_is_hres_active(&rq->hrtick_timer); 1703 } 1704 1705 void hrtick_start(struct rq *rq, u64 delay); 1706 1707 #else 1708 1709 static inline int hrtick_enabled(struct rq *rq) 1710 { 1711 return 0; 1712 } 1713 1714 #endif /* CONFIG_SCHED_HRTICK */ 1715 1716 #ifndef arch_scale_freq_capacity 1717 static __always_inline 1718 unsigned long arch_scale_freq_capacity(int cpu) 1719 { 1720 return SCHED_CAPACITY_SCALE; 1721 } 1722 #endif 1723 1724 #ifdef CONFIG_SMP 1725 extern void sched_avg_update(struct rq *rq); 1726 1727 #ifndef arch_scale_cpu_capacity 1728 static __always_inline 1729 unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu) 1730 { 1731 if (sd && (sd->flags & SD_SHARE_CPUCAPACITY) && (sd->span_weight > 1)) 1732 return sd->smt_gain / sd->span_weight; 1733 1734 return SCHED_CAPACITY_SCALE; 1735 } 1736 #endif 1737 1738 static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) 1739 { 1740 rq->rt_avg += rt_delta * arch_scale_freq_capacity(cpu_of(rq)); 1741 sched_avg_update(rq); 1742 } 1743 #else 1744 #ifndef arch_scale_cpu_capacity 1745 static __always_inline 1746 unsigned long arch_scale_cpu_capacity(void __always_unused *sd, int cpu) 1747 { 1748 return SCHED_CAPACITY_SCALE; 1749 } 1750 #endif 1751 static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { } 1752 static inline void sched_avg_update(struct rq *rq) { } 1753 #endif 1754 1755 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1756 __acquires(rq->lock); 1757 1758 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1759 __acquires(p->pi_lock) 1760 __acquires(rq->lock); 1761 1762 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf) 1763 __releases(rq->lock) 1764 { 1765 rq_unpin_lock(rq, rf); 1766 raw_spin_unlock(&rq->lock); 1767 } 1768 1769 static inline void 1770 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) 1771 __releases(rq->lock) 1772 __releases(p->pi_lock) 1773 { 1774 rq_unpin_lock(rq, rf); 1775 raw_spin_unlock(&rq->lock); 1776 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); 1777 } 1778 1779 static inline void 1780 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) 1781 __acquires(rq->lock) 1782 { 1783 raw_spin_lock_irqsave(&rq->lock, rf->flags); 1784 rq_pin_lock(rq, rf); 1785 } 1786 1787 static inline void 1788 rq_lock_irq(struct rq *rq, struct rq_flags *rf) 1789 __acquires(rq->lock) 1790 { 1791 raw_spin_lock_irq(&rq->lock); 1792 rq_pin_lock(rq, rf); 1793 } 1794 1795 static inline void 1796 rq_lock(struct rq *rq, struct rq_flags *rf) 1797 __acquires(rq->lock) 1798 { 1799 raw_spin_lock(&rq->lock); 1800 rq_pin_lock(rq, rf); 1801 } 1802 1803 static inline void 1804 rq_relock(struct rq *rq, struct rq_flags *rf) 1805 __acquires(rq->lock) 1806 { 1807 raw_spin_lock(&rq->lock); 1808 rq_repin_lock(rq, rf); 1809 } 1810 1811 static inline void 1812 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf) 1813 __releases(rq->lock) 1814 { 1815 rq_unpin_lock(rq, rf); 1816 raw_spin_unlock_irqrestore(&rq->lock, rf->flags); 1817 } 1818 1819 static inline void 1820 rq_unlock_irq(struct rq *rq, struct rq_flags *rf) 1821 __releases(rq->lock) 1822 { 1823 rq_unpin_lock(rq, rf); 1824 raw_spin_unlock_irq(&rq->lock); 1825 } 1826 1827 static inline void 1828 rq_unlock(struct rq *rq, struct rq_flags *rf) 1829 __releases(rq->lock) 1830 { 1831 rq_unpin_lock(rq, rf); 1832 raw_spin_unlock(&rq->lock); 1833 } 1834 1835 #ifdef CONFIG_SMP 1836 #ifdef CONFIG_PREEMPT 1837 1838 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2); 1839 1840 /* 1841 * fair double_lock_balance: Safely acquires both rq->locks in a fair 1842 * way at the expense of forcing extra atomic operations in all 1843 * invocations. This assures that the double_lock is acquired using the 1844 * same underlying policy as the spinlock_t on this architecture, which 1845 * reduces latency compared to the unfair variant below. However, it 1846 * also adds more overhead and therefore may reduce throughput. 1847 */ 1848 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 1849 __releases(this_rq->lock) 1850 __acquires(busiest->lock) 1851 __acquires(this_rq->lock) 1852 { 1853 raw_spin_unlock(&this_rq->lock); 1854 double_rq_lock(this_rq, busiest); 1855 1856 return 1; 1857 } 1858 1859 #else 1860 /* 1861 * Unfair double_lock_balance: Optimizes throughput at the expense of 1862 * latency by eliminating extra atomic operations when the locks are 1863 * already in proper order on entry. This favors lower CPU-ids and will 1864 * grant the double lock to lower CPUs over higher ids under contention, 1865 * regardless of entry order into the function. 1866 */ 1867 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 1868 __releases(this_rq->lock) 1869 __acquires(busiest->lock) 1870 __acquires(this_rq->lock) 1871 { 1872 int ret = 0; 1873 1874 if (unlikely(!raw_spin_trylock(&busiest->lock))) { 1875 if (busiest < this_rq) { 1876 raw_spin_unlock(&this_rq->lock); 1877 raw_spin_lock(&busiest->lock); 1878 raw_spin_lock_nested(&this_rq->lock, 1879 SINGLE_DEPTH_NESTING); 1880 ret = 1; 1881 } else 1882 raw_spin_lock_nested(&busiest->lock, 1883 SINGLE_DEPTH_NESTING); 1884 } 1885 return ret; 1886 } 1887 1888 #endif /* CONFIG_PREEMPT */ 1889 1890 /* 1891 * double_lock_balance - lock the busiest runqueue, this_rq is locked already. 1892 */ 1893 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest) 1894 { 1895 if (unlikely(!irqs_disabled())) { 1896 /* printk() doesn't work well under rq->lock */ 1897 raw_spin_unlock(&this_rq->lock); 1898 BUG_ON(1); 1899 } 1900 1901 return _double_lock_balance(this_rq, busiest); 1902 } 1903 1904 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest) 1905 __releases(busiest->lock) 1906 { 1907 raw_spin_unlock(&busiest->lock); 1908 lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_); 1909 } 1910 1911 static inline void double_lock(spinlock_t *l1, spinlock_t *l2) 1912 { 1913 if (l1 > l2) 1914 swap(l1, l2); 1915 1916 spin_lock(l1); 1917 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 1918 } 1919 1920 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2) 1921 { 1922 if (l1 > l2) 1923 swap(l1, l2); 1924 1925 spin_lock_irq(l1); 1926 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 1927 } 1928 1929 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2) 1930 { 1931 if (l1 > l2) 1932 swap(l1, l2); 1933 1934 raw_spin_lock(l1); 1935 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 1936 } 1937 1938 /* 1939 * double_rq_lock - safely lock two runqueues 1940 * 1941 * Note this does not disable interrupts like task_rq_lock, 1942 * you need to do so manually before calling. 1943 */ 1944 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2) 1945 __acquires(rq1->lock) 1946 __acquires(rq2->lock) 1947 { 1948 BUG_ON(!irqs_disabled()); 1949 if (rq1 == rq2) { 1950 raw_spin_lock(&rq1->lock); 1951 __acquire(rq2->lock); /* Fake it out ;) */ 1952 } else { 1953 if (rq1 < rq2) { 1954 raw_spin_lock(&rq1->lock); 1955 raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING); 1956 } else { 1957 raw_spin_lock(&rq2->lock); 1958 raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING); 1959 } 1960 } 1961 } 1962 1963 /* 1964 * double_rq_unlock - safely unlock two runqueues 1965 * 1966 * Note this does not restore interrupts like task_rq_unlock, 1967 * you need to do so manually after calling. 1968 */ 1969 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 1970 __releases(rq1->lock) 1971 __releases(rq2->lock) 1972 { 1973 raw_spin_unlock(&rq1->lock); 1974 if (rq1 != rq2) 1975 raw_spin_unlock(&rq2->lock); 1976 else 1977 __release(rq2->lock); 1978 } 1979 1980 extern void set_rq_online (struct rq *rq); 1981 extern void set_rq_offline(struct rq *rq); 1982 extern bool sched_smp_initialized; 1983 1984 #else /* CONFIG_SMP */ 1985 1986 /* 1987 * double_rq_lock - safely lock two runqueues 1988 * 1989 * Note this does not disable interrupts like task_rq_lock, 1990 * you need to do so manually before calling. 1991 */ 1992 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2) 1993 __acquires(rq1->lock) 1994 __acquires(rq2->lock) 1995 { 1996 BUG_ON(!irqs_disabled()); 1997 BUG_ON(rq1 != rq2); 1998 raw_spin_lock(&rq1->lock); 1999 __acquire(rq2->lock); /* Fake it out ;) */ 2000 } 2001 2002 /* 2003 * double_rq_unlock - safely unlock two runqueues 2004 * 2005 * Note this does not restore interrupts like task_rq_unlock, 2006 * you need to do so manually after calling. 2007 */ 2008 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 2009 __releases(rq1->lock) 2010 __releases(rq2->lock) 2011 { 2012 BUG_ON(rq1 != rq2); 2013 raw_spin_unlock(&rq1->lock); 2014 __release(rq2->lock); 2015 } 2016 2017 #endif 2018 2019 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq); 2020 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq); 2021 2022 #ifdef CONFIG_SCHED_DEBUG 2023 extern bool sched_debug_enabled; 2024 2025 extern void print_cfs_stats(struct seq_file *m, int cpu); 2026 extern void print_rt_stats(struct seq_file *m, int cpu); 2027 extern void print_dl_stats(struct seq_file *m, int cpu); 2028 extern void 2029 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 2030 #ifdef CONFIG_NUMA_BALANCING 2031 extern void 2032 show_numa_stats(struct task_struct *p, struct seq_file *m); 2033 extern void 2034 print_numa_stats(struct seq_file *m, int node, unsigned long tsf, 2035 unsigned long tpf, unsigned long gsf, unsigned long gpf); 2036 #endif /* CONFIG_NUMA_BALANCING */ 2037 #endif /* CONFIG_SCHED_DEBUG */ 2038 2039 extern void init_cfs_rq(struct cfs_rq *cfs_rq); 2040 extern void init_rt_rq(struct rt_rq *rt_rq); 2041 extern void init_dl_rq(struct dl_rq *dl_rq); 2042 2043 extern void cfs_bandwidth_usage_inc(void); 2044 extern void cfs_bandwidth_usage_dec(void); 2045 2046 #ifdef CONFIG_NO_HZ_COMMON 2047 #define NOHZ_BALANCE_KICK_BIT 0 2048 #define NOHZ_STATS_KICK_BIT 1 2049 2050 #define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT) 2051 #define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT) 2052 2053 #define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK) 2054 2055 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags) 2056 2057 extern void nohz_balance_exit_idle(struct rq *rq); 2058 #else 2059 static inline void nohz_balance_exit_idle(struct rq *rq) { } 2060 #endif 2061 2062 2063 #ifdef CONFIG_SMP 2064 static inline 2065 void __dl_update(struct dl_bw *dl_b, s64 bw) 2066 { 2067 struct root_domain *rd = container_of(dl_b, struct root_domain, dl_bw); 2068 int i; 2069 2070 RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(), 2071 "sched RCU must be held"); 2072 for_each_cpu_and(i, rd->span, cpu_active_mask) { 2073 struct rq *rq = cpu_rq(i); 2074 2075 rq->dl.extra_bw += bw; 2076 } 2077 } 2078 #else 2079 static inline 2080 void __dl_update(struct dl_bw *dl_b, s64 bw) 2081 { 2082 struct dl_rq *dl = container_of(dl_b, struct dl_rq, dl_bw); 2083 2084 dl->extra_bw += bw; 2085 } 2086 #endif 2087 2088 2089 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 2090 struct irqtime { 2091 u64 total; 2092 u64 tick_delta; 2093 u64 irq_start_time; 2094 struct u64_stats_sync sync; 2095 }; 2096 2097 DECLARE_PER_CPU(struct irqtime, cpu_irqtime); 2098 2099 /* 2100 * Returns the irqtime minus the softirq time computed by ksoftirqd. 2101 * Otherwise ksoftirqd's sum_exec_runtime is substracted its own runtime 2102 * and never move forward. 2103 */ 2104 static inline u64 irq_time_read(int cpu) 2105 { 2106 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu); 2107 unsigned int seq; 2108 u64 total; 2109 2110 do { 2111 seq = __u64_stats_fetch_begin(&irqtime->sync); 2112 total = irqtime->total; 2113 } while (__u64_stats_fetch_retry(&irqtime->sync, seq)); 2114 2115 return total; 2116 } 2117 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */ 2118 2119 #ifdef CONFIG_CPU_FREQ 2120 DECLARE_PER_CPU(struct update_util_data *, cpufreq_update_util_data); 2121 2122 /** 2123 * cpufreq_update_util - Take a note about CPU utilization changes. 2124 * @rq: Runqueue to carry out the update for. 2125 * @flags: Update reason flags. 2126 * 2127 * This function is called by the scheduler on the CPU whose utilization is 2128 * being updated. 2129 * 2130 * It can only be called from RCU-sched read-side critical sections. 2131 * 2132 * The way cpufreq is currently arranged requires it to evaluate the CPU 2133 * performance state (frequency/voltage) on a regular basis to prevent it from 2134 * being stuck in a completely inadequate performance level for too long. 2135 * That is not guaranteed to happen if the updates are only triggered from CFS 2136 * and DL, though, because they may not be coming in if only RT tasks are 2137 * active all the time (or there are RT tasks only). 2138 * 2139 * As a workaround for that issue, this function is called periodically by the 2140 * RT sched class to trigger extra cpufreq updates to prevent it from stalling, 2141 * but that really is a band-aid. Going forward it should be replaced with 2142 * solutions targeted more specifically at RT tasks. 2143 */ 2144 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) 2145 { 2146 struct update_util_data *data; 2147 2148 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data, 2149 cpu_of(rq))); 2150 if (data) 2151 data->func(data, rq_clock(rq), flags); 2152 } 2153 #else 2154 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {} 2155 #endif /* CONFIG_CPU_FREQ */ 2156 2157 #ifdef arch_scale_freq_capacity 2158 # ifndef arch_scale_freq_invariant 2159 # define arch_scale_freq_invariant() true 2160 # endif 2161 #else 2162 # define arch_scale_freq_invariant() false 2163 #endif 2164 2165 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL 2166 static inline unsigned long cpu_util_dl(struct rq *rq) 2167 { 2168 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT; 2169 } 2170 2171 static inline unsigned long cpu_util_cfs(struct rq *rq) 2172 { 2173 unsigned long util = READ_ONCE(rq->cfs.avg.util_avg); 2174 2175 if (sched_feat(UTIL_EST)) { 2176 util = max_t(unsigned long, util, 2177 READ_ONCE(rq->cfs.avg.util_est.enqueued)); 2178 } 2179 2180 return util; 2181 } 2182 #endif 2183