1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Scheduler internal types and methods: 4 */ 5 #ifndef _KERNEL_SCHED_SCHED_H 6 #define _KERNEL_SCHED_SCHED_H 7 8 #include <linux/sched/affinity.h> 9 #include <linux/sched/autogroup.h> 10 #include <linux/sched/cpufreq.h> 11 #include <linux/sched/deadline.h> 12 #include <linux/sched.h> 13 #include <linux/sched/loadavg.h> 14 #include <linux/sched/mm.h> 15 #include <linux/sched/rseq_api.h> 16 #include <linux/sched/signal.h> 17 #include <linux/sched/smt.h> 18 #include <linux/sched/stat.h> 19 #include <linux/sched/sysctl.h> 20 #include <linux/sched/task_flags.h> 21 #include <linux/sched/task.h> 22 #include <linux/sched/topology.h> 23 24 #include <linux/atomic.h> 25 #include <linux/bitmap.h> 26 #include <linux/bug.h> 27 #include <linux/capability.h> 28 #include <linux/cgroup_api.h> 29 #include <linux/cgroup.h> 30 #include <linux/context_tracking.h> 31 #include <linux/cpufreq.h> 32 #include <linux/cpumask_api.h> 33 #include <linux/ctype.h> 34 #include <linux/file.h> 35 #include <linux/fs_api.h> 36 #include <linux/hrtimer_api.h> 37 #include <linux/interrupt.h> 38 #include <linux/irq_work.h> 39 #include <linux/jiffies.h> 40 #include <linux/kref_api.h> 41 #include <linux/kthread.h> 42 #include <linux/ktime_api.h> 43 #include <linux/lockdep_api.h> 44 #include <linux/lockdep.h> 45 #include <linux/minmax.h> 46 #include <linux/mm.h> 47 #include <linux/module.h> 48 #include <linux/mutex_api.h> 49 #include <linux/plist.h> 50 #include <linux/poll.h> 51 #include <linux/proc_fs.h> 52 #include <linux/profile.h> 53 #include <linux/psi.h> 54 #include <linux/rcupdate.h> 55 #include <linux/seq_file.h> 56 #include <linux/seqlock.h> 57 #include <linux/softirq.h> 58 #include <linux/spinlock_api.h> 59 #include <linux/static_key.h> 60 #include <linux/stop_machine.h> 61 #include <linux/syscalls_api.h> 62 #include <linux/syscalls.h> 63 #include <linux/tick.h> 64 #include <linux/topology.h> 65 #include <linux/types.h> 66 #include <linux/u64_stats_sync_api.h> 67 #include <linux/uaccess.h> 68 #include <linux/wait_api.h> 69 #include <linux/wait_bit.h> 70 #include <linux/workqueue_api.h> 71 72 #include <trace/events/power.h> 73 #include <trace/events/sched.h> 74 75 #include "../workqueue_internal.h" 76 77 #ifdef CONFIG_CGROUP_SCHED 78 #include <linux/cgroup.h> 79 #include <linux/psi.h> 80 #endif 81 82 #ifdef CONFIG_SCHED_DEBUG 83 # include <linux/static_key.h> 84 #endif 85 86 #ifdef CONFIG_PARAVIRT 87 # include <asm/paravirt.h> 88 # include <asm/paravirt_api_clock.h> 89 #endif 90 91 #include "cpupri.h" 92 #include "cpudeadline.h" 93 94 #ifdef CONFIG_SCHED_DEBUG 95 # define SCHED_WARN_ON(x) WARN_ONCE(x, #x) 96 #else 97 # define SCHED_WARN_ON(x) ({ (void)(x), 0; }) 98 #endif 99 100 struct rq; 101 struct cpuidle_state; 102 103 /* task_struct::on_rq states: */ 104 #define TASK_ON_RQ_QUEUED 1 105 #define TASK_ON_RQ_MIGRATING 2 106 107 extern __read_mostly int scheduler_running; 108 109 extern unsigned long calc_load_update; 110 extern atomic_long_t calc_load_tasks; 111 112 extern unsigned int sysctl_sched_child_runs_first; 113 114 extern void calc_global_load_tick(struct rq *this_rq); 115 extern long calc_load_fold_active(struct rq *this_rq, long adjust); 116 117 extern void call_trace_sched_update_nr_running(struct rq *rq, int count); 118 119 extern unsigned int sysctl_sched_rt_period; 120 extern int sysctl_sched_rt_runtime; 121 extern int sched_rr_timeslice; 122 123 /* 124 * Helpers for converting nanosecond timing to jiffy resolution 125 */ 126 #define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ)) 127 128 /* 129 * Increase resolution of nice-level calculations for 64-bit architectures. 130 * The extra resolution improves shares distribution and load balancing of 131 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup 132 * hierarchies, especially on larger systems. This is not a user-visible change 133 * and does not change the user-interface for setting shares/weights. 134 * 135 * We increase resolution only if we have enough bits to allow this increased 136 * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit 137 * are pretty high and the returns do not justify the increased costs. 138 * 139 * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to 140 * increase coverage and consistency always enable it on 64-bit platforms. 141 */ 142 #ifdef CONFIG_64BIT 143 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT) 144 # define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT) 145 # define scale_load_down(w) \ 146 ({ \ 147 unsigned long __w = (w); \ 148 if (__w) \ 149 __w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \ 150 __w; \ 151 }) 152 #else 153 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT) 154 # define scale_load(w) (w) 155 # define scale_load_down(w) (w) 156 #endif 157 158 /* 159 * Task weight (visible to users) and its load (invisible to users) have 160 * independent resolution, but they should be well calibrated. We use 161 * scale_load() and scale_load_down(w) to convert between them. The 162 * following must be true: 163 * 164 * scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD 165 * 166 */ 167 #define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT) 168 169 /* 170 * Single value that decides SCHED_DEADLINE internal math precision. 171 * 10 -> just above 1us 172 * 9 -> just above 0.5us 173 */ 174 #define DL_SCALE 10 175 176 /* 177 * Single value that denotes runtime == period, ie unlimited time. 178 */ 179 #define RUNTIME_INF ((u64)~0ULL) 180 181 static inline int idle_policy(int policy) 182 { 183 return policy == SCHED_IDLE; 184 } 185 static inline int fair_policy(int policy) 186 { 187 return policy == SCHED_NORMAL || policy == SCHED_BATCH; 188 } 189 190 static inline int rt_policy(int policy) 191 { 192 return policy == SCHED_FIFO || policy == SCHED_RR; 193 } 194 195 static inline int dl_policy(int policy) 196 { 197 return policy == SCHED_DEADLINE; 198 } 199 static inline bool valid_policy(int policy) 200 { 201 return idle_policy(policy) || fair_policy(policy) || 202 rt_policy(policy) || dl_policy(policy); 203 } 204 205 static inline int task_has_idle_policy(struct task_struct *p) 206 { 207 return idle_policy(p->policy); 208 } 209 210 static inline int task_has_rt_policy(struct task_struct *p) 211 { 212 return rt_policy(p->policy); 213 } 214 215 static inline int task_has_dl_policy(struct task_struct *p) 216 { 217 return dl_policy(p->policy); 218 } 219 220 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT) 221 222 static inline void update_avg(u64 *avg, u64 sample) 223 { 224 s64 diff = sample - *avg; 225 *avg += diff / 8; 226 } 227 228 /* 229 * Shifting a value by an exponent greater *or equal* to the size of said value 230 * is UB; cap at size-1. 231 */ 232 #define shr_bound(val, shift) \ 233 (val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1)) 234 235 /* 236 * !! For sched_setattr_nocheck() (kernel) only !! 237 * 238 * This is actually gross. :( 239 * 240 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE 241 * tasks, but still be able to sleep. We need this on platforms that cannot 242 * atomically change clock frequency. Remove once fast switching will be 243 * available on such platforms. 244 * 245 * SUGOV stands for SchedUtil GOVernor. 246 */ 247 #define SCHED_FLAG_SUGOV 0x10000000 248 249 #define SCHED_DL_FLAGS (SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV) 250 251 static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se) 252 { 253 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL 254 return unlikely(dl_se->flags & SCHED_FLAG_SUGOV); 255 #else 256 return false; 257 #endif 258 } 259 260 /* 261 * Tells if entity @a should preempt entity @b. 262 */ 263 static inline bool 264 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b) 265 { 266 return dl_entity_is_special(a) || 267 dl_time_before(a->deadline, b->deadline); 268 } 269 270 /* 271 * This is the priority-queue data structure of the RT scheduling class: 272 */ 273 struct rt_prio_array { 274 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */ 275 struct list_head queue[MAX_RT_PRIO]; 276 }; 277 278 struct rt_bandwidth { 279 /* nests inside the rq lock: */ 280 raw_spinlock_t rt_runtime_lock; 281 ktime_t rt_period; 282 u64 rt_runtime; 283 struct hrtimer rt_period_timer; 284 unsigned int rt_period_active; 285 }; 286 287 void __dl_clear_params(struct task_struct *p); 288 289 struct dl_bandwidth { 290 raw_spinlock_t dl_runtime_lock; 291 u64 dl_runtime; 292 u64 dl_period; 293 }; 294 295 static inline int dl_bandwidth_enabled(void) 296 { 297 return sysctl_sched_rt_runtime >= 0; 298 } 299 300 /* 301 * To keep the bandwidth of -deadline tasks under control 302 * we need some place where: 303 * - store the maximum -deadline bandwidth of each cpu; 304 * - cache the fraction of bandwidth that is currently allocated in 305 * each root domain; 306 * 307 * This is all done in the data structure below. It is similar to the 308 * one used for RT-throttling (rt_bandwidth), with the main difference 309 * that, since here we are only interested in admission control, we 310 * do not decrease any runtime while the group "executes", neither we 311 * need a timer to replenish it. 312 * 313 * With respect to SMP, bandwidth is given on a per root domain basis, 314 * meaning that: 315 * - bw (< 100%) is the deadline bandwidth of each CPU; 316 * - total_bw is the currently allocated bandwidth in each root domain; 317 */ 318 struct dl_bw { 319 raw_spinlock_t lock; 320 u64 bw; 321 u64 total_bw; 322 }; 323 324 /* 325 * Verify the fitness of task @p to run on @cpu taking into account the 326 * CPU original capacity and the runtime/deadline ratio of the task. 327 * 328 * The function will return true if the CPU original capacity of the 329 * @cpu scaled by SCHED_CAPACITY_SCALE >= runtime/deadline ratio of the 330 * task and false otherwise. 331 */ 332 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu) 333 { 334 unsigned long cap = arch_scale_cpu_capacity(cpu); 335 336 return cap_scale(p->dl.dl_deadline, cap) >= p->dl.dl_runtime; 337 } 338 339 extern void init_dl_bw(struct dl_bw *dl_b); 340 extern int sched_dl_global_validate(void); 341 extern void sched_dl_do_global(void); 342 extern int sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr); 343 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr); 344 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr); 345 extern bool __checkparam_dl(const struct sched_attr *attr); 346 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr); 347 extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 348 extern int dl_cpu_busy(int cpu, struct task_struct *p); 349 350 #ifdef CONFIG_CGROUP_SCHED 351 352 struct cfs_rq; 353 struct rt_rq; 354 355 extern struct list_head task_groups; 356 357 struct cfs_bandwidth { 358 #ifdef CONFIG_CFS_BANDWIDTH 359 raw_spinlock_t lock; 360 ktime_t period; 361 u64 quota; 362 u64 runtime; 363 u64 burst; 364 u64 runtime_snap; 365 s64 hierarchical_quota; 366 367 u8 idle; 368 u8 period_active; 369 u8 slack_started; 370 struct hrtimer period_timer; 371 struct hrtimer slack_timer; 372 struct list_head throttled_cfs_rq; 373 374 /* Statistics: */ 375 int nr_periods; 376 int nr_throttled; 377 int nr_burst; 378 u64 throttled_time; 379 u64 burst_time; 380 #endif 381 }; 382 383 /* Task group related information */ 384 struct task_group { 385 struct cgroup_subsys_state css; 386 387 #ifdef CONFIG_FAIR_GROUP_SCHED 388 /* schedulable entities of this group on each CPU */ 389 struct sched_entity **se; 390 /* runqueue "owned" by this group on each CPU */ 391 struct cfs_rq **cfs_rq; 392 unsigned long shares; 393 394 /* A positive value indicates that this is a SCHED_IDLE group. */ 395 int idle; 396 397 #ifdef CONFIG_SMP 398 /* 399 * load_avg can be heavily contended at clock tick time, so put 400 * it in its own cacheline separated from the fields above which 401 * will also be accessed at each tick. 402 */ 403 atomic_long_t load_avg ____cacheline_aligned; 404 #endif 405 #endif 406 407 #ifdef CONFIG_RT_GROUP_SCHED 408 struct sched_rt_entity **rt_se; 409 struct rt_rq **rt_rq; 410 411 struct rt_bandwidth rt_bandwidth; 412 #endif 413 414 struct rcu_head rcu; 415 struct list_head list; 416 417 struct task_group *parent; 418 struct list_head siblings; 419 struct list_head children; 420 421 #ifdef CONFIG_SCHED_AUTOGROUP 422 struct autogroup *autogroup; 423 #endif 424 425 struct cfs_bandwidth cfs_bandwidth; 426 427 #ifdef CONFIG_UCLAMP_TASK_GROUP 428 /* The two decimal precision [%] value requested from user-space */ 429 unsigned int uclamp_pct[UCLAMP_CNT]; 430 /* Clamp values requested for a task group */ 431 struct uclamp_se uclamp_req[UCLAMP_CNT]; 432 /* Effective clamp values used for a task group */ 433 struct uclamp_se uclamp[UCLAMP_CNT]; 434 #endif 435 436 }; 437 438 #ifdef CONFIG_FAIR_GROUP_SCHED 439 #define ROOT_TASK_GROUP_LOAD NICE_0_LOAD 440 441 /* 442 * A weight of 0 or 1 can cause arithmetics problems. 443 * A weight of a cfs_rq is the sum of weights of which entities 444 * are queued on this cfs_rq, so a weight of a entity should not be 445 * too large, so as the shares value of a task group. 446 * (The default weight is 1024 - so there's no practical 447 * limitation from this.) 448 */ 449 #define MIN_SHARES (1UL << 1) 450 #define MAX_SHARES (1UL << 18) 451 #endif 452 453 typedef int (*tg_visitor)(struct task_group *, void *); 454 455 extern int walk_tg_tree_from(struct task_group *from, 456 tg_visitor down, tg_visitor up, void *data); 457 458 /* 459 * Iterate the full tree, calling @down when first entering a node and @up when 460 * leaving it for the final time. 461 * 462 * Caller must hold rcu_lock or sufficient equivalent. 463 */ 464 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data) 465 { 466 return walk_tg_tree_from(&root_task_group, down, up, data); 467 } 468 469 extern int tg_nop(struct task_group *tg, void *data); 470 471 extern void free_fair_sched_group(struct task_group *tg); 472 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent); 473 extern void online_fair_sched_group(struct task_group *tg); 474 extern void unregister_fair_sched_group(struct task_group *tg); 475 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, 476 struct sched_entity *se, int cpu, 477 struct sched_entity *parent); 478 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b); 479 480 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b); 481 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b); 482 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq); 483 484 extern void unregister_rt_sched_group(struct task_group *tg); 485 extern void free_rt_sched_group(struct task_group *tg); 486 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent); 487 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, 488 struct sched_rt_entity *rt_se, int cpu, 489 struct sched_rt_entity *parent); 490 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us); 491 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us); 492 extern long sched_group_rt_runtime(struct task_group *tg); 493 extern long sched_group_rt_period(struct task_group *tg); 494 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk); 495 496 extern struct task_group *sched_create_group(struct task_group *parent); 497 extern void sched_online_group(struct task_group *tg, 498 struct task_group *parent); 499 extern void sched_destroy_group(struct task_group *tg); 500 extern void sched_release_group(struct task_group *tg); 501 502 extern void sched_move_task(struct task_struct *tsk); 503 504 #ifdef CONFIG_FAIR_GROUP_SCHED 505 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); 506 507 extern int sched_group_set_idle(struct task_group *tg, long idle); 508 509 #ifdef CONFIG_SMP 510 extern void set_task_rq_fair(struct sched_entity *se, 511 struct cfs_rq *prev, struct cfs_rq *next); 512 #else /* !CONFIG_SMP */ 513 static inline void set_task_rq_fair(struct sched_entity *se, 514 struct cfs_rq *prev, struct cfs_rq *next) { } 515 #endif /* CONFIG_SMP */ 516 #endif /* CONFIG_FAIR_GROUP_SCHED */ 517 518 #else /* CONFIG_CGROUP_SCHED */ 519 520 struct cfs_bandwidth { }; 521 522 #endif /* CONFIG_CGROUP_SCHED */ 523 524 /* CFS-related fields in a runqueue */ 525 struct cfs_rq { 526 struct load_weight load; 527 unsigned int nr_running; 528 unsigned int h_nr_running; /* SCHED_{NORMAL,BATCH,IDLE} */ 529 unsigned int idle_nr_running; /* SCHED_IDLE */ 530 unsigned int idle_h_nr_running; /* SCHED_IDLE */ 531 532 u64 exec_clock; 533 u64 min_vruntime; 534 #ifdef CONFIG_SCHED_CORE 535 unsigned int forceidle_seq; 536 u64 min_vruntime_fi; 537 #endif 538 539 #ifndef CONFIG_64BIT 540 u64 min_vruntime_copy; 541 #endif 542 543 struct rb_root_cached tasks_timeline; 544 545 /* 546 * 'curr' points to currently running entity on this cfs_rq. 547 * It is set to NULL otherwise (i.e when none are currently running). 548 */ 549 struct sched_entity *curr; 550 struct sched_entity *next; 551 struct sched_entity *last; 552 struct sched_entity *skip; 553 554 #ifdef CONFIG_SCHED_DEBUG 555 unsigned int nr_spread_over; 556 #endif 557 558 #ifdef CONFIG_SMP 559 /* 560 * CFS load tracking 561 */ 562 struct sched_avg avg; 563 #ifndef CONFIG_64BIT 564 u64 load_last_update_time_copy; 565 #endif 566 struct { 567 raw_spinlock_t lock ____cacheline_aligned; 568 int nr; 569 unsigned long load_avg; 570 unsigned long util_avg; 571 unsigned long runnable_avg; 572 } removed; 573 574 #ifdef CONFIG_FAIR_GROUP_SCHED 575 unsigned long tg_load_avg_contrib; 576 long propagate; 577 long prop_runnable_sum; 578 579 /* 580 * h_load = weight * f(tg) 581 * 582 * Where f(tg) is the recursive weight fraction assigned to 583 * this group. 584 */ 585 unsigned long h_load; 586 u64 last_h_load_update; 587 struct sched_entity *h_load_next; 588 #endif /* CONFIG_FAIR_GROUP_SCHED */ 589 #endif /* CONFIG_SMP */ 590 591 #ifdef CONFIG_FAIR_GROUP_SCHED 592 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */ 593 594 /* 595 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in 596 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities 597 * (like users, containers etc.) 598 * 599 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU. 600 * This list is used during load balance. 601 */ 602 int on_list; 603 struct list_head leaf_cfs_rq_list; 604 struct task_group *tg; /* group that "owns" this runqueue */ 605 606 /* Locally cached copy of our task_group's idle value */ 607 int idle; 608 609 #ifdef CONFIG_CFS_BANDWIDTH 610 int runtime_enabled; 611 s64 runtime_remaining; 612 613 u64 throttled_clock; 614 u64 throttled_clock_pelt; 615 u64 throttled_clock_pelt_time; 616 int throttled; 617 int throttle_count; 618 struct list_head throttled_list; 619 #endif /* CONFIG_CFS_BANDWIDTH */ 620 #endif /* CONFIG_FAIR_GROUP_SCHED */ 621 }; 622 623 static inline int rt_bandwidth_enabled(void) 624 { 625 return sysctl_sched_rt_runtime >= 0; 626 } 627 628 /* RT IPI pull logic requires IRQ_WORK */ 629 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP) 630 # define HAVE_RT_PUSH_IPI 631 #endif 632 633 /* Real-Time classes' related field in a runqueue: */ 634 struct rt_rq { 635 struct rt_prio_array active; 636 unsigned int rt_nr_running; 637 unsigned int rr_nr_running; 638 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED 639 struct { 640 int curr; /* highest queued rt task prio */ 641 #ifdef CONFIG_SMP 642 int next; /* next highest */ 643 #endif 644 } highest_prio; 645 #endif 646 #ifdef CONFIG_SMP 647 unsigned int rt_nr_migratory; 648 unsigned int rt_nr_total; 649 int overloaded; 650 struct plist_head pushable_tasks; 651 652 #endif /* CONFIG_SMP */ 653 int rt_queued; 654 655 int rt_throttled; 656 u64 rt_time; 657 u64 rt_runtime; 658 /* Nests inside the rq lock: */ 659 raw_spinlock_t rt_runtime_lock; 660 661 #ifdef CONFIG_RT_GROUP_SCHED 662 unsigned int rt_nr_boosted; 663 664 struct rq *rq; 665 struct task_group *tg; 666 #endif 667 }; 668 669 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq) 670 { 671 return rt_rq->rt_queued && rt_rq->rt_nr_running; 672 } 673 674 /* Deadline class' related fields in a runqueue */ 675 struct dl_rq { 676 /* runqueue is an rbtree, ordered by deadline */ 677 struct rb_root_cached root; 678 679 unsigned int dl_nr_running; 680 681 #ifdef CONFIG_SMP 682 /* 683 * Deadline values of the currently executing and the 684 * earliest ready task on this rq. Caching these facilitates 685 * the decision whether or not a ready but not running task 686 * should migrate somewhere else. 687 */ 688 struct { 689 u64 curr; 690 u64 next; 691 } earliest_dl; 692 693 unsigned int dl_nr_migratory; 694 int overloaded; 695 696 /* 697 * Tasks on this rq that can be pushed away. They are kept in 698 * an rb-tree, ordered by tasks' deadlines, with caching 699 * of the leftmost (earliest deadline) element. 700 */ 701 struct rb_root_cached pushable_dl_tasks_root; 702 #else 703 struct dl_bw dl_bw; 704 #endif 705 /* 706 * "Active utilization" for this runqueue: increased when a 707 * task wakes up (becomes TASK_RUNNING) and decreased when a 708 * task blocks 709 */ 710 u64 running_bw; 711 712 /* 713 * Utilization of the tasks "assigned" to this runqueue (including 714 * the tasks that are in runqueue and the tasks that executed on this 715 * CPU and blocked). Increased when a task moves to this runqueue, and 716 * decreased when the task moves away (migrates, changes scheduling 717 * policy, or terminates). 718 * This is needed to compute the "inactive utilization" for the 719 * runqueue (inactive utilization = this_bw - running_bw). 720 */ 721 u64 this_bw; 722 u64 extra_bw; 723 724 /* 725 * Inverse of the fraction of CPU utilization that can be reclaimed 726 * by the GRUB algorithm. 727 */ 728 u64 bw_ratio; 729 }; 730 731 #ifdef CONFIG_FAIR_GROUP_SCHED 732 /* An entity is a task if it doesn't "own" a runqueue */ 733 #define entity_is_task(se) (!se->my_q) 734 735 static inline void se_update_runnable(struct sched_entity *se) 736 { 737 if (!entity_is_task(se)) 738 se->runnable_weight = se->my_q->h_nr_running; 739 } 740 741 static inline long se_runnable(struct sched_entity *se) 742 { 743 if (entity_is_task(se)) 744 return !!se->on_rq; 745 else 746 return se->runnable_weight; 747 } 748 749 #else 750 #define entity_is_task(se) 1 751 752 static inline void se_update_runnable(struct sched_entity *se) {} 753 754 static inline long se_runnable(struct sched_entity *se) 755 { 756 return !!se->on_rq; 757 } 758 #endif 759 760 #ifdef CONFIG_SMP 761 /* 762 * XXX we want to get rid of these helpers and use the full load resolution. 763 */ 764 static inline long se_weight(struct sched_entity *se) 765 { 766 return scale_load_down(se->load.weight); 767 } 768 769 770 static inline bool sched_asym_prefer(int a, int b) 771 { 772 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b); 773 } 774 775 struct perf_domain { 776 struct em_perf_domain *em_pd; 777 struct perf_domain *next; 778 struct rcu_head rcu; 779 }; 780 781 /* Scheduling group status flags */ 782 #define SG_OVERLOAD 0x1 /* More than one runnable task on a CPU. */ 783 #define SG_OVERUTILIZED 0x2 /* One or more CPUs are over-utilized. */ 784 785 /* 786 * We add the notion of a root-domain which will be used to define per-domain 787 * variables. Each exclusive cpuset essentially defines an island domain by 788 * fully partitioning the member CPUs from any other cpuset. Whenever a new 789 * exclusive cpuset is created, we also create and attach a new root-domain 790 * object. 791 * 792 */ 793 struct root_domain { 794 atomic_t refcount; 795 atomic_t rto_count; 796 struct rcu_head rcu; 797 cpumask_var_t span; 798 cpumask_var_t online; 799 800 /* 801 * Indicate pullable load on at least one CPU, e.g: 802 * - More than one runnable task 803 * - Running task is misfit 804 */ 805 int overload; 806 807 /* Indicate one or more cpus over-utilized (tipping point) */ 808 int overutilized; 809 810 /* 811 * The bit corresponding to a CPU gets set here if such CPU has more 812 * than one runnable -deadline task (as it is below for RT tasks). 813 */ 814 cpumask_var_t dlo_mask; 815 atomic_t dlo_count; 816 struct dl_bw dl_bw; 817 struct cpudl cpudl; 818 819 /* 820 * Indicate whether a root_domain's dl_bw has been checked or 821 * updated. It's monotonously increasing value. 822 * 823 * Also, some corner cases, like 'wrap around' is dangerous, but given 824 * that u64 is 'big enough'. So that shouldn't be a concern. 825 */ 826 u64 visit_gen; 827 828 #ifdef HAVE_RT_PUSH_IPI 829 /* 830 * For IPI pull requests, loop across the rto_mask. 831 */ 832 struct irq_work rto_push_work; 833 raw_spinlock_t rto_lock; 834 /* These are only updated and read within rto_lock */ 835 int rto_loop; 836 int rto_cpu; 837 /* These atomics are updated outside of a lock */ 838 atomic_t rto_loop_next; 839 atomic_t rto_loop_start; 840 #endif 841 /* 842 * The "RT overload" flag: it gets set if a CPU has more than 843 * one runnable RT task. 844 */ 845 cpumask_var_t rto_mask; 846 struct cpupri cpupri; 847 848 unsigned long max_cpu_capacity; 849 850 /* 851 * NULL-terminated list of performance domains intersecting with the 852 * CPUs of the rd. Protected by RCU. 853 */ 854 struct perf_domain __rcu *pd; 855 }; 856 857 extern void init_defrootdomain(void); 858 extern int sched_init_domains(const struct cpumask *cpu_map); 859 extern void rq_attach_root(struct rq *rq, struct root_domain *rd); 860 extern void sched_get_rd(struct root_domain *rd); 861 extern void sched_put_rd(struct root_domain *rd); 862 863 #ifdef HAVE_RT_PUSH_IPI 864 extern void rto_push_irq_work_func(struct irq_work *work); 865 #endif 866 #endif /* CONFIG_SMP */ 867 868 #ifdef CONFIG_UCLAMP_TASK 869 /* 870 * struct uclamp_bucket - Utilization clamp bucket 871 * @value: utilization clamp value for tasks on this clamp bucket 872 * @tasks: number of RUNNABLE tasks on this clamp bucket 873 * 874 * Keep track of how many tasks are RUNNABLE for a given utilization 875 * clamp value. 876 */ 877 struct uclamp_bucket { 878 unsigned long value : bits_per(SCHED_CAPACITY_SCALE); 879 unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE); 880 }; 881 882 /* 883 * struct uclamp_rq - rq's utilization clamp 884 * @value: currently active clamp values for a rq 885 * @bucket: utilization clamp buckets affecting a rq 886 * 887 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values. 888 * A clamp value is affecting a rq when there is at least one task RUNNABLE 889 * (or actually running) with that value. 890 * 891 * There are up to UCLAMP_CNT possible different clamp values, currently there 892 * are only two: minimum utilization and maximum utilization. 893 * 894 * All utilization clamping values are MAX aggregated, since: 895 * - for util_min: we want to run the CPU at least at the max of the minimum 896 * utilization required by its currently RUNNABLE tasks. 897 * - for util_max: we want to allow the CPU to run up to the max of the 898 * maximum utilization allowed by its currently RUNNABLE tasks. 899 * 900 * Since on each system we expect only a limited number of different 901 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track 902 * the metrics required to compute all the per-rq utilization clamp values. 903 */ 904 struct uclamp_rq { 905 unsigned int value; 906 struct uclamp_bucket bucket[UCLAMP_BUCKETS]; 907 }; 908 909 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used); 910 #endif /* CONFIG_UCLAMP_TASK */ 911 912 /* 913 * This is the main, per-CPU runqueue data structure. 914 * 915 * Locking rule: those places that want to lock multiple runqueues 916 * (such as the load balancing or the thread migration code), lock 917 * acquire operations must be ordered by ascending &runqueue. 918 */ 919 struct rq { 920 /* runqueue lock: */ 921 raw_spinlock_t __lock; 922 923 /* 924 * nr_running and cpu_load should be in the same cacheline because 925 * remote CPUs use both these fields when doing load calculation. 926 */ 927 unsigned int nr_running; 928 #ifdef CONFIG_NUMA_BALANCING 929 unsigned int nr_numa_running; 930 unsigned int nr_preferred_running; 931 unsigned int numa_migrate_on; 932 #endif 933 #ifdef CONFIG_NO_HZ_COMMON 934 #ifdef CONFIG_SMP 935 unsigned long last_blocked_load_update_tick; 936 unsigned int has_blocked_load; 937 call_single_data_t nohz_csd; 938 #endif /* CONFIG_SMP */ 939 unsigned int nohz_tick_stopped; 940 atomic_t nohz_flags; 941 #endif /* CONFIG_NO_HZ_COMMON */ 942 943 #ifdef CONFIG_SMP 944 unsigned int ttwu_pending; 945 #endif 946 u64 nr_switches; 947 948 #ifdef CONFIG_UCLAMP_TASK 949 /* Utilization clamp values based on CPU's RUNNABLE tasks */ 950 struct uclamp_rq uclamp[UCLAMP_CNT] ____cacheline_aligned; 951 unsigned int uclamp_flags; 952 #define UCLAMP_FLAG_IDLE 0x01 953 #endif 954 955 struct cfs_rq cfs; 956 struct rt_rq rt; 957 struct dl_rq dl; 958 959 #ifdef CONFIG_FAIR_GROUP_SCHED 960 /* list of leaf cfs_rq on this CPU: */ 961 struct list_head leaf_cfs_rq_list; 962 struct list_head *tmp_alone_branch; 963 #endif /* CONFIG_FAIR_GROUP_SCHED */ 964 965 /* 966 * This is part of a global counter where only the total sum 967 * over all CPUs matters. A task can increase this counter on 968 * one CPU and if it got migrated afterwards it may decrease 969 * it on another CPU. Always updated under the runqueue lock: 970 */ 971 unsigned int nr_uninterruptible; 972 973 struct task_struct __rcu *curr; 974 struct task_struct *idle; 975 struct task_struct *stop; 976 unsigned long next_balance; 977 struct mm_struct *prev_mm; 978 979 unsigned int clock_update_flags; 980 u64 clock; 981 /* Ensure that all clocks are in the same cache line */ 982 u64 clock_task ____cacheline_aligned; 983 u64 clock_pelt; 984 unsigned long lost_idle_time; 985 986 atomic_t nr_iowait; 987 988 #ifdef CONFIG_SCHED_DEBUG 989 u64 last_seen_need_resched_ns; 990 int ticks_without_resched; 991 #endif 992 993 #ifdef CONFIG_MEMBARRIER 994 int membarrier_state; 995 #endif 996 997 #ifdef CONFIG_SMP 998 struct root_domain *rd; 999 struct sched_domain __rcu *sd; 1000 1001 unsigned long cpu_capacity; 1002 unsigned long cpu_capacity_orig; 1003 1004 struct callback_head *balance_callback; 1005 1006 unsigned char nohz_idle_balance; 1007 unsigned char idle_balance; 1008 1009 unsigned long misfit_task_load; 1010 1011 /* For active balancing */ 1012 int active_balance; 1013 int push_cpu; 1014 struct cpu_stop_work active_balance_work; 1015 1016 /* CPU of this runqueue: */ 1017 int cpu; 1018 int online; 1019 1020 struct list_head cfs_tasks; 1021 1022 struct sched_avg avg_rt; 1023 struct sched_avg avg_dl; 1024 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 1025 struct sched_avg avg_irq; 1026 #endif 1027 #ifdef CONFIG_SCHED_THERMAL_PRESSURE 1028 struct sched_avg avg_thermal; 1029 #endif 1030 u64 idle_stamp; 1031 u64 avg_idle; 1032 1033 unsigned long wake_stamp; 1034 u64 wake_avg_idle; 1035 1036 /* This is used to determine avg_idle's max value */ 1037 u64 max_idle_balance_cost; 1038 1039 #ifdef CONFIG_HOTPLUG_CPU 1040 struct rcuwait hotplug_wait; 1041 #endif 1042 #endif /* CONFIG_SMP */ 1043 1044 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 1045 u64 prev_irq_time; 1046 #endif 1047 #ifdef CONFIG_PARAVIRT 1048 u64 prev_steal_time; 1049 #endif 1050 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING 1051 u64 prev_steal_time_rq; 1052 #endif 1053 1054 /* calc_load related fields */ 1055 unsigned long calc_load_update; 1056 long calc_load_active; 1057 1058 #ifdef CONFIG_SCHED_HRTICK 1059 #ifdef CONFIG_SMP 1060 call_single_data_t hrtick_csd; 1061 #endif 1062 struct hrtimer hrtick_timer; 1063 ktime_t hrtick_time; 1064 #endif 1065 1066 #ifdef CONFIG_SCHEDSTATS 1067 /* latency stats */ 1068 struct sched_info rq_sched_info; 1069 unsigned long long rq_cpu_time; 1070 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */ 1071 1072 /* sys_sched_yield() stats */ 1073 unsigned int yld_count; 1074 1075 /* schedule() stats */ 1076 unsigned int sched_count; 1077 unsigned int sched_goidle; 1078 1079 /* try_to_wake_up() stats */ 1080 unsigned int ttwu_count; 1081 unsigned int ttwu_local; 1082 #endif 1083 1084 #ifdef CONFIG_CPU_IDLE 1085 /* Must be inspected within a rcu lock section */ 1086 struct cpuidle_state *idle_state; 1087 #endif 1088 1089 #ifdef CONFIG_SMP 1090 unsigned int nr_pinned; 1091 #endif 1092 unsigned int push_busy; 1093 struct cpu_stop_work push_work; 1094 1095 #ifdef CONFIG_SCHED_CORE 1096 /* per rq */ 1097 struct rq *core; 1098 struct task_struct *core_pick; 1099 unsigned int core_enabled; 1100 unsigned int core_sched_seq; 1101 struct rb_root core_tree; 1102 1103 /* shared state -- careful with sched_core_cpu_deactivate() */ 1104 unsigned int core_task_seq; 1105 unsigned int core_pick_seq; 1106 unsigned long core_cookie; 1107 unsigned int core_forceidle_count; 1108 unsigned int core_forceidle_seq; 1109 unsigned int core_forceidle_occupation; 1110 u64 core_forceidle_start; 1111 #endif 1112 }; 1113 1114 #ifdef CONFIG_FAIR_GROUP_SCHED 1115 1116 /* CPU runqueue to which this cfs_rq is attached */ 1117 static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1118 { 1119 return cfs_rq->rq; 1120 } 1121 1122 #else 1123 1124 static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1125 { 1126 return container_of(cfs_rq, struct rq, cfs); 1127 } 1128 #endif 1129 1130 static inline int cpu_of(struct rq *rq) 1131 { 1132 #ifdef CONFIG_SMP 1133 return rq->cpu; 1134 #else 1135 return 0; 1136 #endif 1137 } 1138 1139 #define MDF_PUSH 0x01 1140 1141 static inline bool is_migration_disabled(struct task_struct *p) 1142 { 1143 #ifdef CONFIG_SMP 1144 return p->migration_disabled; 1145 #else 1146 return false; 1147 #endif 1148 } 1149 1150 struct sched_group; 1151 #ifdef CONFIG_SCHED_CORE 1152 static inline struct cpumask *sched_group_span(struct sched_group *sg); 1153 1154 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled); 1155 1156 static inline bool sched_core_enabled(struct rq *rq) 1157 { 1158 return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled; 1159 } 1160 1161 static inline bool sched_core_disabled(void) 1162 { 1163 return !static_branch_unlikely(&__sched_core_enabled); 1164 } 1165 1166 /* 1167 * Be careful with this function; not for general use. The return value isn't 1168 * stable unless you actually hold a relevant rq->__lock. 1169 */ 1170 static inline raw_spinlock_t *rq_lockp(struct rq *rq) 1171 { 1172 if (sched_core_enabled(rq)) 1173 return &rq->core->__lock; 1174 1175 return &rq->__lock; 1176 } 1177 1178 static inline raw_spinlock_t *__rq_lockp(struct rq *rq) 1179 { 1180 if (rq->core_enabled) 1181 return &rq->core->__lock; 1182 1183 return &rq->__lock; 1184 } 1185 1186 bool cfs_prio_less(struct task_struct *a, struct task_struct *b, bool fi); 1187 1188 /* 1189 * Helpers to check if the CPU's core cookie matches with the task's cookie 1190 * when core scheduling is enabled. 1191 * A special case is that the task's cookie always matches with CPU's core 1192 * cookie if the CPU is in an idle core. 1193 */ 1194 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p) 1195 { 1196 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1197 if (!sched_core_enabled(rq)) 1198 return true; 1199 1200 return rq->core->core_cookie == p->core_cookie; 1201 } 1202 1203 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) 1204 { 1205 bool idle_core = true; 1206 int cpu; 1207 1208 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1209 if (!sched_core_enabled(rq)) 1210 return true; 1211 1212 for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) { 1213 if (!available_idle_cpu(cpu)) { 1214 idle_core = false; 1215 break; 1216 } 1217 } 1218 1219 /* 1220 * A CPU in an idle core is always the best choice for tasks with 1221 * cookies. 1222 */ 1223 return idle_core || rq->core->core_cookie == p->core_cookie; 1224 } 1225 1226 static inline bool sched_group_cookie_match(struct rq *rq, 1227 struct task_struct *p, 1228 struct sched_group *group) 1229 { 1230 int cpu; 1231 1232 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1233 if (!sched_core_enabled(rq)) 1234 return true; 1235 1236 for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) { 1237 if (sched_core_cookie_match(rq, p)) 1238 return true; 1239 } 1240 return false; 1241 } 1242 1243 static inline bool sched_core_enqueued(struct task_struct *p) 1244 { 1245 return !RB_EMPTY_NODE(&p->core_node); 1246 } 1247 1248 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p); 1249 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags); 1250 1251 extern void sched_core_get(void); 1252 extern void sched_core_put(void); 1253 1254 #else /* !CONFIG_SCHED_CORE */ 1255 1256 static inline bool sched_core_enabled(struct rq *rq) 1257 { 1258 return false; 1259 } 1260 1261 static inline bool sched_core_disabled(void) 1262 { 1263 return true; 1264 } 1265 1266 static inline raw_spinlock_t *rq_lockp(struct rq *rq) 1267 { 1268 return &rq->__lock; 1269 } 1270 1271 static inline raw_spinlock_t *__rq_lockp(struct rq *rq) 1272 { 1273 return &rq->__lock; 1274 } 1275 1276 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p) 1277 { 1278 return true; 1279 } 1280 1281 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) 1282 { 1283 return true; 1284 } 1285 1286 static inline bool sched_group_cookie_match(struct rq *rq, 1287 struct task_struct *p, 1288 struct sched_group *group) 1289 { 1290 return true; 1291 } 1292 #endif /* CONFIG_SCHED_CORE */ 1293 1294 static inline void lockdep_assert_rq_held(struct rq *rq) 1295 { 1296 lockdep_assert_held(__rq_lockp(rq)); 1297 } 1298 1299 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass); 1300 extern bool raw_spin_rq_trylock(struct rq *rq); 1301 extern void raw_spin_rq_unlock(struct rq *rq); 1302 1303 static inline void raw_spin_rq_lock(struct rq *rq) 1304 { 1305 raw_spin_rq_lock_nested(rq, 0); 1306 } 1307 1308 static inline void raw_spin_rq_lock_irq(struct rq *rq) 1309 { 1310 local_irq_disable(); 1311 raw_spin_rq_lock(rq); 1312 } 1313 1314 static inline void raw_spin_rq_unlock_irq(struct rq *rq) 1315 { 1316 raw_spin_rq_unlock(rq); 1317 local_irq_enable(); 1318 } 1319 1320 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq) 1321 { 1322 unsigned long flags; 1323 local_irq_save(flags); 1324 raw_spin_rq_lock(rq); 1325 return flags; 1326 } 1327 1328 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags) 1329 { 1330 raw_spin_rq_unlock(rq); 1331 local_irq_restore(flags); 1332 } 1333 1334 #define raw_spin_rq_lock_irqsave(rq, flags) \ 1335 do { \ 1336 flags = _raw_spin_rq_lock_irqsave(rq); \ 1337 } while (0) 1338 1339 #ifdef CONFIG_SCHED_SMT 1340 extern void __update_idle_core(struct rq *rq); 1341 1342 static inline void update_idle_core(struct rq *rq) 1343 { 1344 if (static_branch_unlikely(&sched_smt_present)) 1345 __update_idle_core(rq); 1346 } 1347 1348 #else 1349 static inline void update_idle_core(struct rq *rq) { } 1350 #endif 1351 1352 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); 1353 1354 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) 1355 #define this_rq() this_cpu_ptr(&runqueues) 1356 #define task_rq(p) cpu_rq(task_cpu(p)) 1357 #define cpu_curr(cpu) (cpu_rq(cpu)->curr) 1358 #define raw_rq() raw_cpu_ptr(&runqueues) 1359 1360 #ifdef CONFIG_FAIR_GROUP_SCHED 1361 static inline struct task_struct *task_of(struct sched_entity *se) 1362 { 1363 SCHED_WARN_ON(!entity_is_task(se)); 1364 return container_of(se, struct task_struct, se); 1365 } 1366 1367 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p) 1368 { 1369 return p->se.cfs_rq; 1370 } 1371 1372 /* runqueue on which this entity is (to be) queued */ 1373 static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se) 1374 { 1375 return se->cfs_rq; 1376 } 1377 1378 /* runqueue "owned" by this group */ 1379 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) 1380 { 1381 return grp->my_q; 1382 } 1383 1384 #else 1385 1386 static inline struct task_struct *task_of(struct sched_entity *se) 1387 { 1388 return container_of(se, struct task_struct, se); 1389 } 1390 1391 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p) 1392 { 1393 return &task_rq(p)->cfs; 1394 } 1395 1396 static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se) 1397 { 1398 struct task_struct *p = task_of(se); 1399 struct rq *rq = task_rq(p); 1400 1401 return &rq->cfs; 1402 } 1403 1404 /* runqueue "owned" by this group */ 1405 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) 1406 { 1407 return NULL; 1408 } 1409 #endif 1410 1411 extern void update_rq_clock(struct rq *rq); 1412 1413 /* 1414 * rq::clock_update_flags bits 1415 * 1416 * %RQCF_REQ_SKIP - will request skipping of clock update on the next 1417 * call to __schedule(). This is an optimisation to avoid 1418 * neighbouring rq clock updates. 1419 * 1420 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is 1421 * in effect and calls to update_rq_clock() are being ignored. 1422 * 1423 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been 1424 * made to update_rq_clock() since the last time rq::lock was pinned. 1425 * 1426 * If inside of __schedule(), clock_update_flags will have been 1427 * shifted left (a left shift is a cheap operation for the fast path 1428 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use, 1429 * 1430 * if (rq-clock_update_flags >= RQCF_UPDATED) 1431 * 1432 * to check if %RQCF_UPDATED is set. It'll never be shifted more than 1433 * one position though, because the next rq_unpin_lock() will shift it 1434 * back. 1435 */ 1436 #define RQCF_REQ_SKIP 0x01 1437 #define RQCF_ACT_SKIP 0x02 1438 #define RQCF_UPDATED 0x04 1439 1440 static inline void assert_clock_updated(struct rq *rq) 1441 { 1442 /* 1443 * The only reason for not seeing a clock update since the 1444 * last rq_pin_lock() is if we're currently skipping updates. 1445 */ 1446 SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP); 1447 } 1448 1449 static inline u64 rq_clock(struct rq *rq) 1450 { 1451 lockdep_assert_rq_held(rq); 1452 assert_clock_updated(rq); 1453 1454 return rq->clock; 1455 } 1456 1457 static inline u64 rq_clock_task(struct rq *rq) 1458 { 1459 lockdep_assert_rq_held(rq); 1460 assert_clock_updated(rq); 1461 1462 return rq->clock_task; 1463 } 1464 1465 /** 1466 * By default the decay is the default pelt decay period. 1467 * The decay shift can change the decay period in 1468 * multiples of 32. 1469 * Decay shift Decay period(ms) 1470 * 0 32 1471 * 1 64 1472 * 2 128 1473 * 3 256 1474 * 4 512 1475 */ 1476 extern int sched_thermal_decay_shift; 1477 1478 static inline u64 rq_clock_thermal(struct rq *rq) 1479 { 1480 return rq_clock_task(rq) >> sched_thermal_decay_shift; 1481 } 1482 1483 static inline void rq_clock_skip_update(struct rq *rq) 1484 { 1485 lockdep_assert_rq_held(rq); 1486 rq->clock_update_flags |= RQCF_REQ_SKIP; 1487 } 1488 1489 /* 1490 * See rt task throttling, which is the only time a skip 1491 * request is canceled. 1492 */ 1493 static inline void rq_clock_cancel_skipupdate(struct rq *rq) 1494 { 1495 lockdep_assert_rq_held(rq); 1496 rq->clock_update_flags &= ~RQCF_REQ_SKIP; 1497 } 1498 1499 struct rq_flags { 1500 unsigned long flags; 1501 struct pin_cookie cookie; 1502 #ifdef CONFIG_SCHED_DEBUG 1503 /* 1504 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the 1505 * current pin context is stashed here in case it needs to be 1506 * restored in rq_repin_lock(). 1507 */ 1508 unsigned int clock_update_flags; 1509 #endif 1510 }; 1511 1512 extern struct callback_head balance_push_callback; 1513 1514 /* 1515 * Lockdep annotation that avoids accidental unlocks; it's like a 1516 * sticky/continuous lockdep_assert_held(). 1517 * 1518 * This avoids code that has access to 'struct rq *rq' (basically everything in 1519 * the scheduler) from accidentally unlocking the rq if they do not also have a 1520 * copy of the (on-stack) 'struct rq_flags rf'. 1521 * 1522 * Also see Documentation/locking/lockdep-design.rst. 1523 */ 1524 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf) 1525 { 1526 rf->cookie = lockdep_pin_lock(__rq_lockp(rq)); 1527 1528 #ifdef CONFIG_SCHED_DEBUG 1529 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 1530 rf->clock_update_flags = 0; 1531 #ifdef CONFIG_SMP 1532 SCHED_WARN_ON(rq->balance_callback && rq->balance_callback != &balance_push_callback); 1533 #endif 1534 #endif 1535 } 1536 1537 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf) 1538 { 1539 #ifdef CONFIG_SCHED_DEBUG 1540 if (rq->clock_update_flags > RQCF_ACT_SKIP) 1541 rf->clock_update_flags = RQCF_UPDATED; 1542 #endif 1543 1544 lockdep_unpin_lock(__rq_lockp(rq), rf->cookie); 1545 } 1546 1547 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf) 1548 { 1549 lockdep_repin_lock(__rq_lockp(rq), rf->cookie); 1550 1551 #ifdef CONFIG_SCHED_DEBUG 1552 /* 1553 * Restore the value we stashed in @rf for this pin context. 1554 */ 1555 rq->clock_update_flags |= rf->clock_update_flags; 1556 #endif 1557 } 1558 1559 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1560 __acquires(rq->lock); 1561 1562 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1563 __acquires(p->pi_lock) 1564 __acquires(rq->lock); 1565 1566 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf) 1567 __releases(rq->lock) 1568 { 1569 rq_unpin_lock(rq, rf); 1570 raw_spin_rq_unlock(rq); 1571 } 1572 1573 static inline void 1574 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) 1575 __releases(rq->lock) 1576 __releases(p->pi_lock) 1577 { 1578 rq_unpin_lock(rq, rf); 1579 raw_spin_rq_unlock(rq); 1580 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); 1581 } 1582 1583 static inline void 1584 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) 1585 __acquires(rq->lock) 1586 { 1587 raw_spin_rq_lock_irqsave(rq, rf->flags); 1588 rq_pin_lock(rq, rf); 1589 } 1590 1591 static inline void 1592 rq_lock_irq(struct rq *rq, struct rq_flags *rf) 1593 __acquires(rq->lock) 1594 { 1595 raw_spin_rq_lock_irq(rq); 1596 rq_pin_lock(rq, rf); 1597 } 1598 1599 static inline void 1600 rq_lock(struct rq *rq, struct rq_flags *rf) 1601 __acquires(rq->lock) 1602 { 1603 raw_spin_rq_lock(rq); 1604 rq_pin_lock(rq, rf); 1605 } 1606 1607 static inline void 1608 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf) 1609 __releases(rq->lock) 1610 { 1611 rq_unpin_lock(rq, rf); 1612 raw_spin_rq_unlock_irqrestore(rq, rf->flags); 1613 } 1614 1615 static inline void 1616 rq_unlock_irq(struct rq *rq, struct rq_flags *rf) 1617 __releases(rq->lock) 1618 { 1619 rq_unpin_lock(rq, rf); 1620 raw_spin_rq_unlock_irq(rq); 1621 } 1622 1623 static inline void 1624 rq_unlock(struct rq *rq, struct rq_flags *rf) 1625 __releases(rq->lock) 1626 { 1627 rq_unpin_lock(rq, rf); 1628 raw_spin_rq_unlock(rq); 1629 } 1630 1631 static inline struct rq * 1632 this_rq_lock_irq(struct rq_flags *rf) 1633 __acquires(rq->lock) 1634 { 1635 struct rq *rq; 1636 1637 local_irq_disable(); 1638 rq = this_rq(); 1639 rq_lock(rq, rf); 1640 return rq; 1641 } 1642 1643 #ifdef CONFIG_NUMA 1644 enum numa_topology_type { 1645 NUMA_DIRECT, 1646 NUMA_GLUELESS_MESH, 1647 NUMA_BACKPLANE, 1648 }; 1649 extern enum numa_topology_type sched_numa_topology_type; 1650 extern int sched_max_numa_distance; 1651 extern bool find_numa_distance(int distance); 1652 extern void sched_init_numa(int offline_node); 1653 extern void sched_update_numa(int cpu, bool online); 1654 extern void sched_domains_numa_masks_set(unsigned int cpu); 1655 extern void sched_domains_numa_masks_clear(unsigned int cpu); 1656 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu); 1657 #else 1658 static inline void sched_init_numa(int offline_node) { } 1659 static inline void sched_update_numa(int cpu, bool online) { } 1660 static inline void sched_domains_numa_masks_set(unsigned int cpu) { } 1661 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { } 1662 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu) 1663 { 1664 return nr_cpu_ids; 1665 } 1666 #endif 1667 1668 #ifdef CONFIG_NUMA_BALANCING 1669 /* The regions in numa_faults array from task_struct */ 1670 enum numa_faults_stats { 1671 NUMA_MEM = 0, 1672 NUMA_CPU, 1673 NUMA_MEMBUF, 1674 NUMA_CPUBUF 1675 }; 1676 extern void sched_setnuma(struct task_struct *p, int node); 1677 extern int migrate_task_to(struct task_struct *p, int cpu); 1678 extern int migrate_swap(struct task_struct *p, struct task_struct *t, 1679 int cpu, int scpu); 1680 extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p); 1681 #else 1682 static inline void 1683 init_numa_balancing(unsigned long clone_flags, struct task_struct *p) 1684 { 1685 } 1686 #endif /* CONFIG_NUMA_BALANCING */ 1687 1688 #ifdef CONFIG_SMP 1689 1690 static inline void 1691 queue_balance_callback(struct rq *rq, 1692 struct callback_head *head, 1693 void (*func)(struct rq *rq)) 1694 { 1695 lockdep_assert_rq_held(rq); 1696 1697 /* 1698 * Don't (re)queue an already queued item; nor queue anything when 1699 * balance_push() is active, see the comment with 1700 * balance_push_callback. 1701 */ 1702 if (unlikely(head->next || rq->balance_callback == &balance_push_callback)) 1703 return; 1704 1705 head->func = (void (*)(struct callback_head *))func; 1706 head->next = rq->balance_callback; 1707 rq->balance_callback = head; 1708 } 1709 1710 #define rcu_dereference_check_sched_domain(p) \ 1711 rcu_dereference_check((p), \ 1712 lockdep_is_held(&sched_domains_mutex)) 1713 1714 /* 1715 * The domain tree (rq->sd) is protected by RCU's quiescent state transition. 1716 * See destroy_sched_domains: call_rcu for details. 1717 * 1718 * The domain tree of any CPU may only be accessed from within 1719 * preempt-disabled sections. 1720 */ 1721 #define for_each_domain(cpu, __sd) \ 1722 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \ 1723 __sd; __sd = __sd->parent) 1724 1725 /** 1726 * highest_flag_domain - Return highest sched_domain containing flag. 1727 * @cpu: The CPU whose highest level of sched domain is to 1728 * be returned. 1729 * @flag: The flag to check for the highest sched_domain 1730 * for the given CPU. 1731 * 1732 * Returns the highest sched_domain of a CPU which contains the given flag. 1733 */ 1734 static inline struct sched_domain *highest_flag_domain(int cpu, int flag) 1735 { 1736 struct sched_domain *sd, *hsd = NULL; 1737 1738 for_each_domain(cpu, sd) { 1739 if (!(sd->flags & flag)) 1740 break; 1741 hsd = sd; 1742 } 1743 1744 return hsd; 1745 } 1746 1747 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) 1748 { 1749 struct sched_domain *sd; 1750 1751 for_each_domain(cpu, sd) { 1752 if (sd->flags & flag) 1753 break; 1754 } 1755 1756 return sd; 1757 } 1758 1759 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc); 1760 DECLARE_PER_CPU(int, sd_llc_size); 1761 DECLARE_PER_CPU(int, sd_llc_id); 1762 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared); 1763 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa); 1764 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing); 1765 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity); 1766 extern struct static_key_false sched_asym_cpucapacity; 1767 1768 struct sched_group_capacity { 1769 atomic_t ref; 1770 /* 1771 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity 1772 * for a single CPU. 1773 */ 1774 unsigned long capacity; 1775 unsigned long min_capacity; /* Min per-CPU capacity in group */ 1776 unsigned long max_capacity; /* Max per-CPU capacity in group */ 1777 unsigned long next_update; 1778 int imbalance; /* XXX unrelated to capacity but shared group state */ 1779 1780 #ifdef CONFIG_SCHED_DEBUG 1781 int id; 1782 #endif 1783 1784 unsigned long cpumask[]; /* Balance mask */ 1785 }; 1786 1787 struct sched_group { 1788 struct sched_group *next; /* Must be a circular list */ 1789 atomic_t ref; 1790 1791 unsigned int group_weight; 1792 struct sched_group_capacity *sgc; 1793 int asym_prefer_cpu; /* CPU of highest priority in group */ 1794 int flags; 1795 1796 /* 1797 * The CPUs this group covers. 1798 * 1799 * NOTE: this field is variable length. (Allocated dynamically 1800 * by attaching extra space to the end of the structure, 1801 * depending on how many CPUs the kernel has booted up with) 1802 */ 1803 unsigned long cpumask[]; 1804 }; 1805 1806 static inline struct cpumask *sched_group_span(struct sched_group *sg) 1807 { 1808 return to_cpumask(sg->cpumask); 1809 } 1810 1811 /* 1812 * See build_balance_mask(). 1813 */ 1814 static inline struct cpumask *group_balance_mask(struct sched_group *sg) 1815 { 1816 return to_cpumask(sg->sgc->cpumask); 1817 } 1818 1819 /** 1820 * group_first_cpu - Returns the first CPU in the cpumask of a sched_group. 1821 * @group: The group whose first CPU is to be returned. 1822 */ 1823 static inline unsigned int group_first_cpu(struct sched_group *group) 1824 { 1825 return cpumask_first(sched_group_span(group)); 1826 } 1827 1828 extern int group_balance_cpu(struct sched_group *sg); 1829 1830 #ifdef CONFIG_SCHED_DEBUG 1831 void update_sched_domain_debugfs(void); 1832 void dirty_sched_domain_sysctl(int cpu); 1833 #else 1834 static inline void update_sched_domain_debugfs(void) 1835 { 1836 } 1837 static inline void dirty_sched_domain_sysctl(int cpu) 1838 { 1839 } 1840 #endif 1841 1842 extern int sched_update_scaling(void); 1843 #endif /* CONFIG_SMP */ 1844 1845 #include "stats.h" 1846 1847 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS) 1848 1849 extern void __sched_core_account_forceidle(struct rq *rq); 1850 1851 static inline void sched_core_account_forceidle(struct rq *rq) 1852 { 1853 if (schedstat_enabled()) 1854 __sched_core_account_forceidle(rq); 1855 } 1856 1857 extern void __sched_core_tick(struct rq *rq); 1858 1859 static inline void sched_core_tick(struct rq *rq) 1860 { 1861 if (sched_core_enabled(rq) && schedstat_enabled()) 1862 __sched_core_tick(rq); 1863 } 1864 1865 #else 1866 1867 static inline void sched_core_account_forceidle(struct rq *rq) {} 1868 1869 static inline void sched_core_tick(struct rq *rq) {} 1870 1871 #endif /* CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS */ 1872 1873 #ifdef CONFIG_CGROUP_SCHED 1874 1875 /* 1876 * Return the group to which this tasks belongs. 1877 * 1878 * We cannot use task_css() and friends because the cgroup subsystem 1879 * changes that value before the cgroup_subsys::attach() method is called, 1880 * therefore we cannot pin it and might observe the wrong value. 1881 * 1882 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup 1883 * core changes this before calling sched_move_task(). 1884 * 1885 * Instead we use a 'copy' which is updated from sched_move_task() while 1886 * holding both task_struct::pi_lock and rq::lock. 1887 */ 1888 static inline struct task_group *task_group(struct task_struct *p) 1889 { 1890 return p->sched_task_group; 1891 } 1892 1893 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ 1894 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) 1895 { 1896 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED) 1897 struct task_group *tg = task_group(p); 1898 #endif 1899 1900 #ifdef CONFIG_FAIR_GROUP_SCHED 1901 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]); 1902 p->se.cfs_rq = tg->cfs_rq[cpu]; 1903 p->se.parent = tg->se[cpu]; 1904 #endif 1905 1906 #ifdef CONFIG_RT_GROUP_SCHED 1907 p->rt.rt_rq = tg->rt_rq[cpu]; 1908 p->rt.parent = tg->rt_se[cpu]; 1909 #endif 1910 } 1911 1912 #else /* CONFIG_CGROUP_SCHED */ 1913 1914 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } 1915 static inline struct task_group *task_group(struct task_struct *p) 1916 { 1917 return NULL; 1918 } 1919 1920 #endif /* CONFIG_CGROUP_SCHED */ 1921 1922 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) 1923 { 1924 set_task_rq(p, cpu); 1925 #ifdef CONFIG_SMP 1926 /* 1927 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be 1928 * successfully executed on another CPU. We must ensure that updates of 1929 * per-task data have been completed by this moment. 1930 */ 1931 smp_wmb(); 1932 WRITE_ONCE(task_thread_info(p)->cpu, cpu); 1933 p->wake_cpu = cpu; 1934 #endif 1935 } 1936 1937 /* 1938 * Tunables that become constants when CONFIG_SCHED_DEBUG is off: 1939 */ 1940 #ifdef CONFIG_SCHED_DEBUG 1941 # define const_debug __read_mostly 1942 #else 1943 # define const_debug const 1944 #endif 1945 1946 #define SCHED_FEAT(name, enabled) \ 1947 __SCHED_FEAT_##name , 1948 1949 enum { 1950 #include "features.h" 1951 __SCHED_FEAT_NR, 1952 }; 1953 1954 #undef SCHED_FEAT 1955 1956 #ifdef CONFIG_SCHED_DEBUG 1957 1958 /* 1959 * To support run-time toggling of sched features, all the translation units 1960 * (but core.c) reference the sysctl_sched_features defined in core.c. 1961 */ 1962 extern const_debug unsigned int sysctl_sched_features; 1963 1964 #ifdef CONFIG_JUMP_LABEL 1965 #define SCHED_FEAT(name, enabled) \ 1966 static __always_inline bool static_branch_##name(struct static_key *key) \ 1967 { \ 1968 return static_key_##enabled(key); \ 1969 } 1970 1971 #include "features.h" 1972 #undef SCHED_FEAT 1973 1974 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR]; 1975 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x])) 1976 1977 #else /* !CONFIG_JUMP_LABEL */ 1978 1979 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) 1980 1981 #endif /* CONFIG_JUMP_LABEL */ 1982 1983 #else /* !SCHED_DEBUG */ 1984 1985 /* 1986 * Each translation unit has its own copy of sysctl_sched_features to allow 1987 * constants propagation at compile time and compiler optimization based on 1988 * features default. 1989 */ 1990 #define SCHED_FEAT(name, enabled) \ 1991 (1UL << __SCHED_FEAT_##name) * enabled | 1992 static const_debug __maybe_unused unsigned int sysctl_sched_features = 1993 #include "features.h" 1994 0; 1995 #undef SCHED_FEAT 1996 1997 #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) 1998 1999 #endif /* SCHED_DEBUG */ 2000 2001 extern struct static_key_false sched_numa_balancing; 2002 extern struct static_key_false sched_schedstats; 2003 2004 static inline u64 global_rt_period(void) 2005 { 2006 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC; 2007 } 2008 2009 static inline u64 global_rt_runtime(void) 2010 { 2011 if (sysctl_sched_rt_runtime < 0) 2012 return RUNTIME_INF; 2013 2014 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC; 2015 } 2016 2017 static inline int task_current(struct rq *rq, struct task_struct *p) 2018 { 2019 return rq->curr == p; 2020 } 2021 2022 static inline int task_running(struct rq *rq, struct task_struct *p) 2023 { 2024 #ifdef CONFIG_SMP 2025 return p->on_cpu; 2026 #else 2027 return task_current(rq, p); 2028 #endif 2029 } 2030 2031 static inline int task_on_rq_queued(struct task_struct *p) 2032 { 2033 return p->on_rq == TASK_ON_RQ_QUEUED; 2034 } 2035 2036 static inline int task_on_rq_migrating(struct task_struct *p) 2037 { 2038 return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING; 2039 } 2040 2041 /* Wake flags. The first three directly map to some SD flag value */ 2042 #define WF_EXEC 0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */ 2043 #define WF_FORK 0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */ 2044 #define WF_TTWU 0x08 /* Wakeup; maps to SD_BALANCE_WAKE */ 2045 2046 #define WF_SYNC 0x10 /* Waker goes to sleep after wakeup */ 2047 #define WF_MIGRATED 0x20 /* Internal use, task got migrated */ 2048 #define WF_ON_CPU 0x40 /* Wakee is on_cpu */ 2049 2050 #ifdef CONFIG_SMP 2051 static_assert(WF_EXEC == SD_BALANCE_EXEC); 2052 static_assert(WF_FORK == SD_BALANCE_FORK); 2053 static_assert(WF_TTWU == SD_BALANCE_WAKE); 2054 #endif 2055 2056 /* 2057 * To aid in avoiding the subversion of "niceness" due to uneven distribution 2058 * of tasks with abnormal "nice" values across CPUs the contribution that 2059 * each task makes to its run queue's load is weighted according to its 2060 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a 2061 * scaled version of the new time slice allocation that they receive on time 2062 * slice expiry etc. 2063 */ 2064 2065 #define WEIGHT_IDLEPRIO 3 2066 #define WMULT_IDLEPRIO 1431655765 2067 2068 extern const int sched_prio_to_weight[40]; 2069 extern const u32 sched_prio_to_wmult[40]; 2070 2071 /* 2072 * {de,en}queue flags: 2073 * 2074 * DEQUEUE_SLEEP - task is no longer runnable 2075 * ENQUEUE_WAKEUP - task just became runnable 2076 * 2077 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks 2078 * are in a known state which allows modification. Such pairs 2079 * should preserve as much state as possible. 2080 * 2081 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location 2082 * in the runqueue. 2083 * 2084 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified) 2085 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline) 2086 * ENQUEUE_MIGRATED - the task was migrated during wakeup 2087 * 2088 */ 2089 2090 #define DEQUEUE_SLEEP 0x01 2091 #define DEQUEUE_SAVE 0x02 /* Matches ENQUEUE_RESTORE */ 2092 #define DEQUEUE_MOVE 0x04 /* Matches ENQUEUE_MOVE */ 2093 #define DEQUEUE_NOCLOCK 0x08 /* Matches ENQUEUE_NOCLOCK */ 2094 2095 #define ENQUEUE_WAKEUP 0x01 2096 #define ENQUEUE_RESTORE 0x02 2097 #define ENQUEUE_MOVE 0x04 2098 #define ENQUEUE_NOCLOCK 0x08 2099 2100 #define ENQUEUE_HEAD 0x10 2101 #define ENQUEUE_REPLENISH 0x20 2102 #ifdef CONFIG_SMP 2103 #define ENQUEUE_MIGRATED 0x40 2104 #else 2105 #define ENQUEUE_MIGRATED 0x00 2106 #endif 2107 2108 #define RETRY_TASK ((void *)-1UL) 2109 2110 struct sched_class { 2111 2112 #ifdef CONFIG_UCLAMP_TASK 2113 int uclamp_enabled; 2114 #endif 2115 2116 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags); 2117 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags); 2118 void (*yield_task) (struct rq *rq); 2119 bool (*yield_to_task)(struct rq *rq, struct task_struct *p); 2120 2121 void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags); 2122 2123 struct task_struct *(*pick_next_task)(struct rq *rq); 2124 2125 void (*put_prev_task)(struct rq *rq, struct task_struct *p); 2126 void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first); 2127 2128 #ifdef CONFIG_SMP 2129 int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf); 2130 int (*select_task_rq)(struct task_struct *p, int task_cpu, int flags); 2131 2132 struct task_struct * (*pick_task)(struct rq *rq); 2133 2134 void (*migrate_task_rq)(struct task_struct *p, int new_cpu); 2135 2136 void (*task_woken)(struct rq *this_rq, struct task_struct *task); 2137 2138 void (*set_cpus_allowed)(struct task_struct *p, 2139 const struct cpumask *newmask, 2140 u32 flags); 2141 2142 void (*rq_online)(struct rq *rq); 2143 void (*rq_offline)(struct rq *rq); 2144 2145 struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq); 2146 #endif 2147 2148 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued); 2149 void (*task_fork)(struct task_struct *p); 2150 void (*task_dead)(struct task_struct *p); 2151 2152 /* 2153 * The switched_from() call is allowed to drop rq->lock, therefore we 2154 * cannot assume the switched_from/switched_to pair is serialized by 2155 * rq->lock. They are however serialized by p->pi_lock. 2156 */ 2157 void (*switched_from)(struct rq *this_rq, struct task_struct *task); 2158 void (*switched_to) (struct rq *this_rq, struct task_struct *task); 2159 void (*prio_changed) (struct rq *this_rq, struct task_struct *task, 2160 int oldprio); 2161 2162 unsigned int (*get_rr_interval)(struct rq *rq, 2163 struct task_struct *task); 2164 2165 void (*update_curr)(struct rq *rq); 2166 2167 #define TASK_SET_GROUP 0 2168 #define TASK_MOVE_GROUP 1 2169 2170 #ifdef CONFIG_FAIR_GROUP_SCHED 2171 void (*task_change_group)(struct task_struct *p, int type); 2172 #endif 2173 }; 2174 2175 static inline void put_prev_task(struct rq *rq, struct task_struct *prev) 2176 { 2177 WARN_ON_ONCE(rq->curr != prev); 2178 prev->sched_class->put_prev_task(rq, prev); 2179 } 2180 2181 static inline void set_next_task(struct rq *rq, struct task_struct *next) 2182 { 2183 next->sched_class->set_next_task(rq, next, false); 2184 } 2185 2186 2187 /* 2188 * Helper to define a sched_class instance; each one is placed in a separate 2189 * section which is ordered by the linker script: 2190 * 2191 * include/asm-generic/vmlinux.lds.h 2192 * 2193 * *CAREFUL* they are laid out in *REVERSE* order!!! 2194 * 2195 * Also enforce alignment on the instance, not the type, to guarantee layout. 2196 */ 2197 #define DEFINE_SCHED_CLASS(name) \ 2198 const struct sched_class name##_sched_class \ 2199 __aligned(__alignof__(struct sched_class)) \ 2200 __section("__" #name "_sched_class") 2201 2202 /* Defined in include/asm-generic/vmlinux.lds.h */ 2203 extern struct sched_class __sched_class_highest[]; 2204 extern struct sched_class __sched_class_lowest[]; 2205 2206 #define for_class_range(class, _from, _to) \ 2207 for (class = (_from); class < (_to); class++) 2208 2209 #define for_each_class(class) \ 2210 for_class_range(class, __sched_class_highest, __sched_class_lowest) 2211 2212 #define sched_class_above(_a, _b) ((_a) < (_b)) 2213 2214 extern const struct sched_class stop_sched_class; 2215 extern const struct sched_class dl_sched_class; 2216 extern const struct sched_class rt_sched_class; 2217 extern const struct sched_class fair_sched_class; 2218 extern const struct sched_class idle_sched_class; 2219 2220 static inline bool sched_stop_runnable(struct rq *rq) 2221 { 2222 return rq->stop && task_on_rq_queued(rq->stop); 2223 } 2224 2225 static inline bool sched_dl_runnable(struct rq *rq) 2226 { 2227 return rq->dl.dl_nr_running > 0; 2228 } 2229 2230 static inline bool sched_rt_runnable(struct rq *rq) 2231 { 2232 return rq->rt.rt_queued > 0; 2233 } 2234 2235 static inline bool sched_fair_runnable(struct rq *rq) 2236 { 2237 return rq->cfs.nr_running > 0; 2238 } 2239 2240 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf); 2241 extern struct task_struct *pick_next_task_idle(struct rq *rq); 2242 2243 #define SCA_CHECK 0x01 2244 #define SCA_MIGRATE_DISABLE 0x02 2245 #define SCA_MIGRATE_ENABLE 0x04 2246 #define SCA_USER 0x08 2247 2248 #ifdef CONFIG_SMP 2249 2250 extern void update_group_capacity(struct sched_domain *sd, int cpu); 2251 2252 extern void trigger_load_balance(struct rq *rq); 2253 2254 extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask, u32 flags); 2255 2256 static inline struct task_struct *get_push_task(struct rq *rq) 2257 { 2258 struct task_struct *p = rq->curr; 2259 2260 lockdep_assert_rq_held(rq); 2261 2262 if (rq->push_busy) 2263 return NULL; 2264 2265 if (p->nr_cpus_allowed == 1) 2266 return NULL; 2267 2268 if (p->migration_disabled) 2269 return NULL; 2270 2271 rq->push_busy = true; 2272 return get_task_struct(p); 2273 } 2274 2275 extern int push_cpu_stop(void *arg); 2276 2277 #endif 2278 2279 #ifdef CONFIG_CPU_IDLE 2280 static inline void idle_set_state(struct rq *rq, 2281 struct cpuidle_state *idle_state) 2282 { 2283 rq->idle_state = idle_state; 2284 } 2285 2286 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 2287 { 2288 SCHED_WARN_ON(!rcu_read_lock_held()); 2289 2290 return rq->idle_state; 2291 } 2292 #else 2293 static inline void idle_set_state(struct rq *rq, 2294 struct cpuidle_state *idle_state) 2295 { 2296 } 2297 2298 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 2299 { 2300 return NULL; 2301 } 2302 #endif 2303 2304 extern void schedule_idle(void); 2305 2306 extern void sysrq_sched_debug_show(void); 2307 extern void sched_init_granularity(void); 2308 extern void update_max_interval(void); 2309 2310 extern void init_sched_dl_class(void); 2311 extern void init_sched_rt_class(void); 2312 extern void init_sched_fair_class(void); 2313 2314 extern void reweight_task(struct task_struct *p, int prio); 2315 2316 extern void resched_curr(struct rq *rq); 2317 extern void resched_cpu(int cpu); 2318 2319 extern struct rt_bandwidth def_rt_bandwidth; 2320 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime); 2321 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq); 2322 2323 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime); 2324 extern void init_dl_task_timer(struct sched_dl_entity *dl_se); 2325 extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se); 2326 2327 #define BW_SHIFT 20 2328 #define BW_UNIT (1 << BW_SHIFT) 2329 #define RATIO_SHIFT 8 2330 #define MAX_BW_BITS (64 - BW_SHIFT) 2331 #define MAX_BW ((1ULL << MAX_BW_BITS) - 1) 2332 unsigned long to_ratio(u64 period, u64 runtime); 2333 2334 extern void init_entity_runnable_average(struct sched_entity *se); 2335 extern void post_init_entity_util_avg(struct task_struct *p); 2336 2337 #ifdef CONFIG_NO_HZ_FULL 2338 extern bool sched_can_stop_tick(struct rq *rq); 2339 extern int __init sched_tick_offload_init(void); 2340 2341 /* 2342 * Tick may be needed by tasks in the runqueue depending on their policy and 2343 * requirements. If tick is needed, lets send the target an IPI to kick it out of 2344 * nohz mode if necessary. 2345 */ 2346 static inline void sched_update_tick_dependency(struct rq *rq) 2347 { 2348 int cpu = cpu_of(rq); 2349 2350 if (!tick_nohz_full_cpu(cpu)) 2351 return; 2352 2353 if (sched_can_stop_tick(rq)) 2354 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED); 2355 else 2356 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED); 2357 } 2358 #else 2359 static inline int sched_tick_offload_init(void) { return 0; } 2360 static inline void sched_update_tick_dependency(struct rq *rq) { } 2361 #endif 2362 2363 static inline void add_nr_running(struct rq *rq, unsigned count) 2364 { 2365 unsigned prev_nr = rq->nr_running; 2366 2367 rq->nr_running = prev_nr + count; 2368 if (trace_sched_update_nr_running_tp_enabled()) { 2369 call_trace_sched_update_nr_running(rq, count); 2370 } 2371 2372 #ifdef CONFIG_SMP 2373 if (prev_nr < 2 && rq->nr_running >= 2) { 2374 if (!READ_ONCE(rq->rd->overload)) 2375 WRITE_ONCE(rq->rd->overload, 1); 2376 } 2377 #endif 2378 2379 sched_update_tick_dependency(rq); 2380 } 2381 2382 static inline void sub_nr_running(struct rq *rq, unsigned count) 2383 { 2384 rq->nr_running -= count; 2385 if (trace_sched_update_nr_running_tp_enabled()) { 2386 call_trace_sched_update_nr_running(rq, -count); 2387 } 2388 2389 /* Check if we still need preemption */ 2390 sched_update_tick_dependency(rq); 2391 } 2392 2393 extern void activate_task(struct rq *rq, struct task_struct *p, int flags); 2394 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags); 2395 2396 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags); 2397 2398 extern const_debug unsigned int sysctl_sched_nr_migrate; 2399 extern const_debug unsigned int sysctl_sched_migration_cost; 2400 2401 #ifdef CONFIG_SCHED_DEBUG 2402 extern unsigned int sysctl_sched_latency; 2403 extern unsigned int sysctl_sched_min_granularity; 2404 extern unsigned int sysctl_sched_idle_min_granularity; 2405 extern unsigned int sysctl_sched_wakeup_granularity; 2406 extern int sysctl_resched_latency_warn_ms; 2407 extern int sysctl_resched_latency_warn_once; 2408 2409 extern unsigned int sysctl_sched_tunable_scaling; 2410 2411 extern unsigned int sysctl_numa_balancing_scan_delay; 2412 extern unsigned int sysctl_numa_balancing_scan_period_min; 2413 extern unsigned int sysctl_numa_balancing_scan_period_max; 2414 extern unsigned int sysctl_numa_balancing_scan_size; 2415 #endif 2416 2417 #ifdef CONFIG_SCHED_HRTICK 2418 2419 /* 2420 * Use hrtick when: 2421 * - enabled by features 2422 * - hrtimer is actually high res 2423 */ 2424 static inline int hrtick_enabled(struct rq *rq) 2425 { 2426 if (!cpu_active(cpu_of(rq))) 2427 return 0; 2428 return hrtimer_is_hres_active(&rq->hrtick_timer); 2429 } 2430 2431 static inline int hrtick_enabled_fair(struct rq *rq) 2432 { 2433 if (!sched_feat(HRTICK)) 2434 return 0; 2435 return hrtick_enabled(rq); 2436 } 2437 2438 static inline int hrtick_enabled_dl(struct rq *rq) 2439 { 2440 if (!sched_feat(HRTICK_DL)) 2441 return 0; 2442 return hrtick_enabled(rq); 2443 } 2444 2445 void hrtick_start(struct rq *rq, u64 delay); 2446 2447 #else 2448 2449 static inline int hrtick_enabled_fair(struct rq *rq) 2450 { 2451 return 0; 2452 } 2453 2454 static inline int hrtick_enabled_dl(struct rq *rq) 2455 { 2456 return 0; 2457 } 2458 2459 static inline int hrtick_enabled(struct rq *rq) 2460 { 2461 return 0; 2462 } 2463 2464 #endif /* CONFIG_SCHED_HRTICK */ 2465 2466 #ifndef arch_scale_freq_tick 2467 static __always_inline 2468 void arch_scale_freq_tick(void) 2469 { 2470 } 2471 #endif 2472 2473 #ifndef arch_scale_freq_capacity 2474 /** 2475 * arch_scale_freq_capacity - get the frequency scale factor of a given CPU. 2476 * @cpu: the CPU in question. 2477 * 2478 * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e. 2479 * 2480 * f_curr 2481 * ------ * SCHED_CAPACITY_SCALE 2482 * f_max 2483 */ 2484 static __always_inline 2485 unsigned long arch_scale_freq_capacity(int cpu) 2486 { 2487 return SCHED_CAPACITY_SCALE; 2488 } 2489 #endif 2490 2491 #ifdef CONFIG_SCHED_DEBUG 2492 /* 2493 * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to 2494 * acquire rq lock instead of rq_lock(). So at the end of these two functions 2495 * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of 2496 * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning. 2497 */ 2498 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) 2499 { 2500 rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 2501 /* rq1 == rq2 for !CONFIG_SMP, so just clear RQCF_UPDATED once. */ 2502 #ifdef CONFIG_SMP 2503 rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 2504 #endif 2505 } 2506 #else 2507 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) {} 2508 #endif 2509 2510 #ifdef CONFIG_SMP 2511 2512 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2) 2513 { 2514 #ifdef CONFIG_SCHED_CORE 2515 /* 2516 * In order to not have {0,2},{1,3} turn into into an AB-BA, 2517 * order by core-id first and cpu-id second. 2518 * 2519 * Notably: 2520 * 2521 * double_rq_lock(0,3); will take core-0, core-1 lock 2522 * double_rq_lock(1,2); will take core-1, core-0 lock 2523 * 2524 * when only cpu-id is considered. 2525 */ 2526 if (rq1->core->cpu < rq2->core->cpu) 2527 return true; 2528 if (rq1->core->cpu > rq2->core->cpu) 2529 return false; 2530 2531 /* 2532 * __sched_core_flip() relies on SMT having cpu-id lock order. 2533 */ 2534 #endif 2535 return rq1->cpu < rq2->cpu; 2536 } 2537 2538 extern void double_rq_lock(struct rq *rq1, struct rq *rq2); 2539 2540 #ifdef CONFIG_PREEMPTION 2541 2542 /* 2543 * fair double_lock_balance: Safely acquires both rq->locks in a fair 2544 * way at the expense of forcing extra atomic operations in all 2545 * invocations. This assures that the double_lock is acquired using the 2546 * same underlying policy as the spinlock_t on this architecture, which 2547 * reduces latency compared to the unfair variant below. However, it 2548 * also adds more overhead and therefore may reduce throughput. 2549 */ 2550 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 2551 __releases(this_rq->lock) 2552 __acquires(busiest->lock) 2553 __acquires(this_rq->lock) 2554 { 2555 raw_spin_rq_unlock(this_rq); 2556 double_rq_lock(this_rq, busiest); 2557 2558 return 1; 2559 } 2560 2561 #else 2562 /* 2563 * Unfair double_lock_balance: Optimizes throughput at the expense of 2564 * latency by eliminating extra atomic operations when the locks are 2565 * already in proper order on entry. This favors lower CPU-ids and will 2566 * grant the double lock to lower CPUs over higher ids under contention, 2567 * regardless of entry order into the function. 2568 */ 2569 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 2570 __releases(this_rq->lock) 2571 __acquires(busiest->lock) 2572 __acquires(this_rq->lock) 2573 { 2574 if (__rq_lockp(this_rq) == __rq_lockp(busiest) || 2575 likely(raw_spin_rq_trylock(busiest))) { 2576 double_rq_clock_clear_update(this_rq, busiest); 2577 return 0; 2578 } 2579 2580 if (rq_order_less(this_rq, busiest)) { 2581 raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING); 2582 double_rq_clock_clear_update(this_rq, busiest); 2583 return 0; 2584 } 2585 2586 raw_spin_rq_unlock(this_rq); 2587 double_rq_lock(this_rq, busiest); 2588 2589 return 1; 2590 } 2591 2592 #endif /* CONFIG_PREEMPTION */ 2593 2594 /* 2595 * double_lock_balance - lock the busiest runqueue, this_rq is locked already. 2596 */ 2597 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest) 2598 { 2599 lockdep_assert_irqs_disabled(); 2600 2601 return _double_lock_balance(this_rq, busiest); 2602 } 2603 2604 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest) 2605 __releases(busiest->lock) 2606 { 2607 if (__rq_lockp(this_rq) != __rq_lockp(busiest)) 2608 raw_spin_rq_unlock(busiest); 2609 lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_); 2610 } 2611 2612 static inline void double_lock(spinlock_t *l1, spinlock_t *l2) 2613 { 2614 if (l1 > l2) 2615 swap(l1, l2); 2616 2617 spin_lock(l1); 2618 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 2619 } 2620 2621 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2) 2622 { 2623 if (l1 > l2) 2624 swap(l1, l2); 2625 2626 spin_lock_irq(l1); 2627 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 2628 } 2629 2630 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2) 2631 { 2632 if (l1 > l2) 2633 swap(l1, l2); 2634 2635 raw_spin_lock(l1); 2636 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 2637 } 2638 2639 /* 2640 * double_rq_unlock - safely unlock two runqueues 2641 * 2642 * Note this does not restore interrupts like task_rq_unlock, 2643 * you need to do so manually after calling. 2644 */ 2645 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 2646 __releases(rq1->lock) 2647 __releases(rq2->lock) 2648 { 2649 if (__rq_lockp(rq1) != __rq_lockp(rq2)) 2650 raw_spin_rq_unlock(rq2); 2651 else 2652 __release(rq2->lock); 2653 raw_spin_rq_unlock(rq1); 2654 } 2655 2656 extern void set_rq_online (struct rq *rq); 2657 extern void set_rq_offline(struct rq *rq); 2658 extern bool sched_smp_initialized; 2659 2660 #else /* CONFIG_SMP */ 2661 2662 /* 2663 * double_rq_lock - safely lock two runqueues 2664 * 2665 * Note this does not disable interrupts like task_rq_lock, 2666 * you need to do so manually before calling. 2667 */ 2668 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2) 2669 __acquires(rq1->lock) 2670 __acquires(rq2->lock) 2671 { 2672 BUG_ON(!irqs_disabled()); 2673 BUG_ON(rq1 != rq2); 2674 raw_spin_rq_lock(rq1); 2675 __acquire(rq2->lock); /* Fake it out ;) */ 2676 double_rq_clock_clear_update(rq1, rq2); 2677 } 2678 2679 /* 2680 * double_rq_unlock - safely unlock two runqueues 2681 * 2682 * Note this does not restore interrupts like task_rq_unlock, 2683 * you need to do so manually after calling. 2684 */ 2685 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 2686 __releases(rq1->lock) 2687 __releases(rq2->lock) 2688 { 2689 BUG_ON(rq1 != rq2); 2690 raw_spin_rq_unlock(rq1); 2691 __release(rq2->lock); 2692 } 2693 2694 #endif 2695 2696 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq); 2697 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq); 2698 2699 #ifdef CONFIG_SCHED_DEBUG 2700 extern bool sched_debug_verbose; 2701 2702 extern void print_cfs_stats(struct seq_file *m, int cpu); 2703 extern void print_rt_stats(struct seq_file *m, int cpu); 2704 extern void print_dl_stats(struct seq_file *m, int cpu); 2705 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 2706 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq); 2707 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq); 2708 2709 extern void resched_latency_warn(int cpu, u64 latency); 2710 #ifdef CONFIG_NUMA_BALANCING 2711 extern void 2712 show_numa_stats(struct task_struct *p, struct seq_file *m); 2713 extern void 2714 print_numa_stats(struct seq_file *m, int node, unsigned long tsf, 2715 unsigned long tpf, unsigned long gsf, unsigned long gpf); 2716 #endif /* CONFIG_NUMA_BALANCING */ 2717 #else 2718 static inline void resched_latency_warn(int cpu, u64 latency) {} 2719 #endif /* CONFIG_SCHED_DEBUG */ 2720 2721 extern void init_cfs_rq(struct cfs_rq *cfs_rq); 2722 extern void init_rt_rq(struct rt_rq *rt_rq); 2723 extern void init_dl_rq(struct dl_rq *dl_rq); 2724 2725 extern void cfs_bandwidth_usage_inc(void); 2726 extern void cfs_bandwidth_usage_dec(void); 2727 2728 #ifdef CONFIG_NO_HZ_COMMON 2729 #define NOHZ_BALANCE_KICK_BIT 0 2730 #define NOHZ_STATS_KICK_BIT 1 2731 #define NOHZ_NEWILB_KICK_BIT 2 2732 #define NOHZ_NEXT_KICK_BIT 3 2733 2734 /* Run rebalance_domains() */ 2735 #define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT) 2736 /* Update blocked load */ 2737 #define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT) 2738 /* Update blocked load when entering idle */ 2739 #define NOHZ_NEWILB_KICK BIT(NOHZ_NEWILB_KICK_BIT) 2740 /* Update nohz.next_balance */ 2741 #define NOHZ_NEXT_KICK BIT(NOHZ_NEXT_KICK_BIT) 2742 2743 #define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK) 2744 2745 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags) 2746 2747 extern void nohz_balance_exit_idle(struct rq *rq); 2748 #else 2749 static inline void nohz_balance_exit_idle(struct rq *rq) { } 2750 #endif 2751 2752 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) 2753 extern void nohz_run_idle_balance(int cpu); 2754 #else 2755 static inline void nohz_run_idle_balance(int cpu) { } 2756 #endif 2757 2758 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 2759 struct irqtime { 2760 u64 total; 2761 u64 tick_delta; 2762 u64 irq_start_time; 2763 struct u64_stats_sync sync; 2764 }; 2765 2766 DECLARE_PER_CPU(struct irqtime, cpu_irqtime); 2767 2768 /* 2769 * Returns the irqtime minus the softirq time computed by ksoftirqd. 2770 * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime 2771 * and never move forward. 2772 */ 2773 static inline u64 irq_time_read(int cpu) 2774 { 2775 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu); 2776 unsigned int seq; 2777 u64 total; 2778 2779 do { 2780 seq = __u64_stats_fetch_begin(&irqtime->sync); 2781 total = irqtime->total; 2782 } while (__u64_stats_fetch_retry(&irqtime->sync, seq)); 2783 2784 return total; 2785 } 2786 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */ 2787 2788 #ifdef CONFIG_CPU_FREQ 2789 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data); 2790 2791 /** 2792 * cpufreq_update_util - Take a note about CPU utilization changes. 2793 * @rq: Runqueue to carry out the update for. 2794 * @flags: Update reason flags. 2795 * 2796 * This function is called by the scheduler on the CPU whose utilization is 2797 * being updated. 2798 * 2799 * It can only be called from RCU-sched read-side critical sections. 2800 * 2801 * The way cpufreq is currently arranged requires it to evaluate the CPU 2802 * performance state (frequency/voltage) on a regular basis to prevent it from 2803 * being stuck in a completely inadequate performance level for too long. 2804 * That is not guaranteed to happen if the updates are only triggered from CFS 2805 * and DL, though, because they may not be coming in if only RT tasks are 2806 * active all the time (or there are RT tasks only). 2807 * 2808 * As a workaround for that issue, this function is called periodically by the 2809 * RT sched class to trigger extra cpufreq updates to prevent it from stalling, 2810 * but that really is a band-aid. Going forward it should be replaced with 2811 * solutions targeted more specifically at RT tasks. 2812 */ 2813 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) 2814 { 2815 struct update_util_data *data; 2816 2817 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data, 2818 cpu_of(rq))); 2819 if (data) 2820 data->func(data, rq_clock(rq), flags); 2821 } 2822 #else 2823 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {} 2824 #endif /* CONFIG_CPU_FREQ */ 2825 2826 #ifdef arch_scale_freq_capacity 2827 # ifndef arch_scale_freq_invariant 2828 # define arch_scale_freq_invariant() true 2829 # endif 2830 #else 2831 # define arch_scale_freq_invariant() false 2832 #endif 2833 2834 #ifdef CONFIG_SMP 2835 static inline unsigned long capacity_orig_of(int cpu) 2836 { 2837 return cpu_rq(cpu)->cpu_capacity_orig; 2838 } 2839 2840 /** 2841 * enum cpu_util_type - CPU utilization type 2842 * @FREQUENCY_UTIL: Utilization used to select frequency 2843 * @ENERGY_UTIL: Utilization used during energy calculation 2844 * 2845 * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time 2846 * need to be aggregated differently depending on the usage made of them. This 2847 * enum is used within effective_cpu_util() to differentiate the types of 2848 * utilization expected by the callers, and adjust the aggregation accordingly. 2849 */ 2850 enum cpu_util_type { 2851 FREQUENCY_UTIL, 2852 ENERGY_UTIL, 2853 }; 2854 2855 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs, 2856 unsigned long max, enum cpu_util_type type, 2857 struct task_struct *p); 2858 2859 static inline unsigned long cpu_bw_dl(struct rq *rq) 2860 { 2861 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT; 2862 } 2863 2864 static inline unsigned long cpu_util_dl(struct rq *rq) 2865 { 2866 return READ_ONCE(rq->avg_dl.util_avg); 2867 } 2868 2869 /** 2870 * cpu_util_cfs() - Estimates the amount of CPU capacity used by CFS tasks. 2871 * @cpu: the CPU to get the utilization for. 2872 * 2873 * The unit of the return value must be the same as the one of CPU capacity 2874 * so that CPU utilization can be compared with CPU capacity. 2875 * 2876 * CPU utilization is the sum of running time of runnable tasks plus the 2877 * recent utilization of currently non-runnable tasks on that CPU. 2878 * It represents the amount of CPU capacity currently used by CFS tasks in 2879 * the range [0..max CPU capacity] with max CPU capacity being the CPU 2880 * capacity at f_max. 2881 * 2882 * The estimated CPU utilization is defined as the maximum between CPU 2883 * utilization and sum of the estimated utilization of the currently 2884 * runnable tasks on that CPU. It preserves a utilization "snapshot" of 2885 * previously-executed tasks, which helps better deduce how busy a CPU will 2886 * be when a long-sleeping task wakes up. The contribution to CPU utilization 2887 * of such a task would be significantly decayed at this point of time. 2888 * 2889 * CPU utilization can be higher than the current CPU capacity 2890 * (f_curr/f_max * max CPU capacity) or even the max CPU capacity because 2891 * of rounding errors as well as task migrations or wakeups of new tasks. 2892 * CPU utilization has to be capped to fit into the [0..max CPU capacity] 2893 * range. Otherwise a group of CPUs (CPU0 util = 121% + CPU1 util = 80%) 2894 * could be seen as over-utilized even though CPU1 has 20% of spare CPU 2895 * capacity. CPU utilization is allowed to overshoot current CPU capacity 2896 * though since this is useful for predicting the CPU capacity required 2897 * after task migrations (scheduler-driven DVFS). 2898 * 2899 * Return: (Estimated) utilization for the specified CPU. 2900 */ 2901 static inline unsigned long cpu_util_cfs(int cpu) 2902 { 2903 struct cfs_rq *cfs_rq; 2904 unsigned long util; 2905 2906 cfs_rq = &cpu_rq(cpu)->cfs; 2907 util = READ_ONCE(cfs_rq->avg.util_avg); 2908 2909 if (sched_feat(UTIL_EST)) { 2910 util = max_t(unsigned long, util, 2911 READ_ONCE(cfs_rq->avg.util_est.enqueued)); 2912 } 2913 2914 return min(util, capacity_orig_of(cpu)); 2915 } 2916 2917 static inline unsigned long cpu_util_rt(struct rq *rq) 2918 { 2919 return READ_ONCE(rq->avg_rt.util_avg); 2920 } 2921 #endif 2922 2923 #ifdef CONFIG_UCLAMP_TASK 2924 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id); 2925 2926 /** 2927 * uclamp_rq_util_with - clamp @util with @rq and @p effective uclamp values. 2928 * @rq: The rq to clamp against. Must not be NULL. 2929 * @util: The util value to clamp. 2930 * @p: The task to clamp against. Can be NULL if you want to clamp 2931 * against @rq only. 2932 * 2933 * Clamps the passed @util to the max(@rq, @p) effective uclamp values. 2934 * 2935 * If sched_uclamp_used static key is disabled, then just return the util 2936 * without any clamping since uclamp aggregation at the rq level in the fast 2937 * path is disabled, rendering this operation a NOP. 2938 * 2939 * Use uclamp_eff_value() if you don't care about uclamp values at rq level. It 2940 * will return the correct effective uclamp value of the task even if the 2941 * static key is disabled. 2942 */ 2943 static __always_inline 2944 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util, 2945 struct task_struct *p) 2946 { 2947 unsigned long min_util = 0; 2948 unsigned long max_util = 0; 2949 2950 if (!static_branch_likely(&sched_uclamp_used)) 2951 return util; 2952 2953 if (p) { 2954 min_util = uclamp_eff_value(p, UCLAMP_MIN); 2955 max_util = uclamp_eff_value(p, UCLAMP_MAX); 2956 2957 /* 2958 * Ignore last runnable task's max clamp, as this task will 2959 * reset it. Similarly, no need to read the rq's min clamp. 2960 */ 2961 if (rq->uclamp_flags & UCLAMP_FLAG_IDLE) 2962 goto out; 2963 } 2964 2965 min_util = max_t(unsigned long, min_util, READ_ONCE(rq->uclamp[UCLAMP_MIN].value)); 2966 max_util = max_t(unsigned long, max_util, READ_ONCE(rq->uclamp[UCLAMP_MAX].value)); 2967 out: 2968 /* 2969 * Since CPU's {min,max}_util clamps are MAX aggregated considering 2970 * RUNNABLE tasks with _different_ clamps, we can end up with an 2971 * inversion. Fix it now when the clamps are applied. 2972 */ 2973 if (unlikely(min_util >= max_util)) 2974 return min_util; 2975 2976 return clamp(util, min_util, max_util); 2977 } 2978 2979 /* Is the rq being capped/throttled by uclamp_max? */ 2980 static inline bool uclamp_rq_is_capped(struct rq *rq) 2981 { 2982 unsigned long rq_util; 2983 unsigned long max_util; 2984 2985 if (!static_branch_likely(&sched_uclamp_used)) 2986 return false; 2987 2988 rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq); 2989 max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value); 2990 2991 return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util; 2992 } 2993 2994 /* 2995 * When uclamp is compiled in, the aggregation at rq level is 'turned off' 2996 * by default in the fast path and only gets turned on once userspace performs 2997 * an operation that requires it. 2998 * 2999 * Returns true if userspace opted-in to use uclamp and aggregation at rq level 3000 * hence is active. 3001 */ 3002 static inline bool uclamp_is_used(void) 3003 { 3004 return static_branch_likely(&sched_uclamp_used); 3005 } 3006 #else /* CONFIG_UCLAMP_TASK */ 3007 static inline 3008 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util, 3009 struct task_struct *p) 3010 { 3011 return util; 3012 } 3013 3014 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; } 3015 3016 static inline bool uclamp_is_used(void) 3017 { 3018 return false; 3019 } 3020 #endif /* CONFIG_UCLAMP_TASK */ 3021 3022 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 3023 static inline unsigned long cpu_util_irq(struct rq *rq) 3024 { 3025 return rq->avg_irq.util_avg; 3026 } 3027 3028 static inline 3029 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 3030 { 3031 util *= (max - irq); 3032 util /= max; 3033 3034 return util; 3035 3036 } 3037 #else 3038 static inline unsigned long cpu_util_irq(struct rq *rq) 3039 { 3040 return 0; 3041 } 3042 3043 static inline 3044 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 3045 { 3046 return util; 3047 } 3048 #endif 3049 3050 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) 3051 3052 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus))) 3053 3054 DECLARE_STATIC_KEY_FALSE(sched_energy_present); 3055 3056 static inline bool sched_energy_enabled(void) 3057 { 3058 return static_branch_unlikely(&sched_energy_present); 3059 } 3060 3061 #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */ 3062 3063 #define perf_domain_span(pd) NULL 3064 static inline bool sched_energy_enabled(void) { return false; } 3065 3066 #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */ 3067 3068 #ifdef CONFIG_MEMBARRIER 3069 /* 3070 * The scheduler provides memory barriers required by membarrier between: 3071 * - prior user-space memory accesses and store to rq->membarrier_state, 3072 * - store to rq->membarrier_state and following user-space memory accesses. 3073 * In the same way it provides those guarantees around store to rq->curr. 3074 */ 3075 static inline void membarrier_switch_mm(struct rq *rq, 3076 struct mm_struct *prev_mm, 3077 struct mm_struct *next_mm) 3078 { 3079 int membarrier_state; 3080 3081 if (prev_mm == next_mm) 3082 return; 3083 3084 membarrier_state = atomic_read(&next_mm->membarrier_state); 3085 if (READ_ONCE(rq->membarrier_state) == membarrier_state) 3086 return; 3087 3088 WRITE_ONCE(rq->membarrier_state, membarrier_state); 3089 } 3090 #else 3091 static inline void membarrier_switch_mm(struct rq *rq, 3092 struct mm_struct *prev_mm, 3093 struct mm_struct *next_mm) 3094 { 3095 } 3096 #endif 3097 3098 #ifdef CONFIG_SMP 3099 static inline bool is_per_cpu_kthread(struct task_struct *p) 3100 { 3101 if (!(p->flags & PF_KTHREAD)) 3102 return false; 3103 3104 if (p->nr_cpus_allowed != 1) 3105 return false; 3106 3107 return true; 3108 } 3109 #endif 3110 3111 extern void swake_up_all_locked(struct swait_queue_head *q); 3112 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait); 3113 3114 #ifdef CONFIG_PREEMPT_DYNAMIC 3115 extern int preempt_dynamic_mode; 3116 extern int sched_dynamic_mode(const char *str); 3117 extern void sched_dynamic_update(int mode); 3118 #endif 3119 3120 #endif /* _KERNEL_SCHED_SCHED_H */ 3121