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