1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Scheduler internal types and methods: 4 */ 5 #include <linux/sched.h> 6 7 #include <linux/sched/autogroup.h> 8 #include <linux/sched/clock.h> 9 #include <linux/sched/coredump.h> 10 #include <linux/sched/cpufreq.h> 11 #include <linux/sched/cputime.h> 12 #include <linux/sched/deadline.h> 13 #include <linux/sched/debug.h> 14 #include <linux/sched/hotplug.h> 15 #include <linux/sched/idle.h> 16 #include <linux/sched/init.h> 17 #include <linux/sched/isolation.h> 18 #include <linux/sched/jobctl.h> 19 #include <linux/sched/loadavg.h> 20 #include <linux/sched/mm.h> 21 #include <linux/sched/nohz.h> 22 #include <linux/sched/numa_balancing.h> 23 #include <linux/sched/prio.h> 24 #include <linux/sched/rt.h> 25 #include <linux/sched/signal.h> 26 #include <linux/sched/stat.h> 27 #include <linux/sched/sysctl.h> 28 #include <linux/sched/task.h> 29 #include <linux/sched/task_stack.h> 30 #include <linux/sched/topology.h> 31 #include <linux/sched/user.h> 32 #include <linux/sched/wake_q.h> 33 #include <linux/sched/xacct.h> 34 35 #include <uapi/linux/sched/types.h> 36 37 #include <linux/binfmts.h> 38 #include <linux/blkdev.h> 39 #include <linux/compat.h> 40 #include <linux/context_tracking.h> 41 #include <linux/cpufreq.h> 42 #include <linux/cpuidle.h> 43 #include <linux/cpuset.h> 44 #include <linux/ctype.h> 45 #include <linux/debugfs.h> 46 #include <linux/delayacct.h> 47 #include <linux/init_task.h> 48 #include <linux/kprobes.h> 49 #include <linux/kthread.h> 50 #include <linux/membarrier.h> 51 #include <linux/migrate.h> 52 #include <linux/mmu_context.h> 53 #include <linux/nmi.h> 54 #include <linux/proc_fs.h> 55 #include <linux/prefetch.h> 56 #include <linux/profile.h> 57 #include <linux/psi.h> 58 #include <linux/rcupdate_wait.h> 59 #include <linux/security.h> 60 #include <linux/stop_machine.h> 61 #include <linux/suspend.h> 62 #include <linux/swait.h> 63 #include <linux/syscalls.h> 64 #include <linux/task_work.h> 65 #include <linux/tsacct_kern.h> 66 67 #include <asm/tlb.h> 68 69 #ifdef CONFIG_PARAVIRT 70 # include <asm/paravirt.h> 71 #endif 72 73 #include "cpupri.h" 74 #include "cpudeadline.h" 75 76 #ifdef CONFIG_SCHED_DEBUG 77 # define SCHED_WARN_ON(x) WARN_ONCE(x, #x) 78 #else 79 # define SCHED_WARN_ON(x) ({ (void)(x), 0; }) 80 #endif 81 82 struct rq; 83 struct cpuidle_state; 84 85 /* task_struct::on_rq states: */ 86 #define TASK_ON_RQ_QUEUED 1 87 #define TASK_ON_RQ_MIGRATING 2 88 89 extern __read_mostly int scheduler_running; 90 91 extern unsigned long calc_load_update; 92 extern atomic_long_t calc_load_tasks; 93 94 extern void calc_global_load_tick(struct rq *this_rq); 95 extern long calc_load_fold_active(struct rq *this_rq, long adjust); 96 97 #ifdef CONFIG_SMP 98 extern void cpu_load_update_active(struct rq *this_rq); 99 #else 100 static inline void cpu_load_update_active(struct rq *this_rq) { } 101 #endif 102 103 /* 104 * Helpers for converting nanosecond timing to jiffy resolution 105 */ 106 #define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ)) 107 108 /* 109 * Increase resolution of nice-level calculations for 64-bit architectures. 110 * The extra resolution improves shares distribution and load balancing of 111 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup 112 * hierarchies, especially on larger systems. This is not a user-visible change 113 * and does not change the user-interface for setting shares/weights. 114 * 115 * We increase resolution only if we have enough bits to allow this increased 116 * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit 117 * are pretty high and the returns do not justify the increased costs. 118 * 119 * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to 120 * increase coverage and consistency always enable it on 64-bit platforms. 121 */ 122 #ifdef CONFIG_64BIT 123 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT) 124 # define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT) 125 # define scale_load_down(w) ((w) >> SCHED_FIXEDPOINT_SHIFT) 126 #else 127 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT) 128 # define scale_load(w) (w) 129 # define scale_load_down(w) (w) 130 #endif 131 132 /* 133 * Task weight (visible to users) and its load (invisible to users) have 134 * independent resolution, but they should be well calibrated. We use 135 * scale_load() and scale_load_down(w) to convert between them. The 136 * following must be true: 137 * 138 * scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD 139 * 140 */ 141 #define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT) 142 143 /* 144 * Single value that decides SCHED_DEADLINE internal math precision. 145 * 10 -> just above 1us 146 * 9 -> just above 0.5us 147 */ 148 #define DL_SCALE 10 149 150 /* 151 * Single value that denotes runtime == period, ie unlimited time. 152 */ 153 #define RUNTIME_INF ((u64)~0ULL) 154 155 static inline int idle_policy(int policy) 156 { 157 return policy == SCHED_IDLE; 158 } 159 static inline int fair_policy(int policy) 160 { 161 return policy == SCHED_NORMAL || policy == SCHED_BATCH; 162 } 163 164 static inline int rt_policy(int policy) 165 { 166 return policy == SCHED_FIFO || policy == SCHED_RR; 167 } 168 169 static inline int dl_policy(int policy) 170 { 171 return policy == SCHED_DEADLINE; 172 } 173 static inline bool valid_policy(int policy) 174 { 175 return idle_policy(policy) || fair_policy(policy) || 176 rt_policy(policy) || dl_policy(policy); 177 } 178 179 static inline int task_has_rt_policy(struct task_struct *p) 180 { 181 return rt_policy(p->policy); 182 } 183 184 static inline int task_has_dl_policy(struct task_struct *p) 185 { 186 return dl_policy(p->policy); 187 } 188 189 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT) 190 191 /* 192 * !! For sched_setattr_nocheck() (kernel) only !! 193 * 194 * This is actually gross. :( 195 * 196 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE 197 * tasks, but still be able to sleep. We need this on platforms that cannot 198 * atomically change clock frequency. Remove once fast switching will be 199 * available on such platforms. 200 * 201 * SUGOV stands for SchedUtil GOVernor. 202 */ 203 #define SCHED_FLAG_SUGOV 0x10000000 204 205 static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se) 206 { 207 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL 208 return unlikely(dl_se->flags & SCHED_FLAG_SUGOV); 209 #else 210 return false; 211 #endif 212 } 213 214 /* 215 * Tells if entity @a should preempt entity @b. 216 */ 217 static inline bool 218 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b) 219 { 220 return dl_entity_is_special(a) || 221 dl_time_before(a->deadline, b->deadline); 222 } 223 224 /* 225 * This is the priority-queue data structure of the RT scheduling class: 226 */ 227 struct rt_prio_array { 228 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */ 229 struct list_head queue[MAX_RT_PRIO]; 230 }; 231 232 struct rt_bandwidth { 233 /* nests inside the rq lock: */ 234 raw_spinlock_t rt_runtime_lock; 235 ktime_t rt_period; 236 u64 rt_runtime; 237 struct hrtimer rt_period_timer; 238 unsigned int rt_period_active; 239 }; 240 241 void __dl_clear_params(struct task_struct *p); 242 243 /* 244 * To keep the bandwidth of -deadline tasks and groups under control 245 * we need some place where: 246 * - store the maximum -deadline bandwidth of the system (the group); 247 * - cache the fraction of that bandwidth that is currently allocated. 248 * 249 * This is all done in the data structure below. It is similar to the 250 * one used for RT-throttling (rt_bandwidth), with the main difference 251 * that, since here we are only interested in admission control, we 252 * do not decrease any runtime while the group "executes", neither we 253 * need a timer to replenish it. 254 * 255 * With respect to SMP, the bandwidth is given on a per-CPU basis, 256 * meaning that: 257 * - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU; 258 * - dl_total_bw array contains, in the i-eth element, the currently 259 * allocated bandwidth on the i-eth CPU. 260 * Moreover, groups consume bandwidth on each CPU, while tasks only 261 * consume bandwidth on the CPU they're running on. 262 * Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw 263 * that will be shown the next time the proc or cgroup controls will 264 * be red. It on its turn can be changed by writing on its own 265 * control. 266 */ 267 struct dl_bandwidth { 268 raw_spinlock_t dl_runtime_lock; 269 u64 dl_runtime; 270 u64 dl_period; 271 }; 272 273 static inline int dl_bandwidth_enabled(void) 274 { 275 return sysctl_sched_rt_runtime >= 0; 276 } 277 278 struct dl_bw { 279 raw_spinlock_t lock; 280 u64 bw; 281 u64 total_bw; 282 }; 283 284 static inline void __dl_update(struct dl_bw *dl_b, s64 bw); 285 286 static inline 287 void __dl_sub(struct dl_bw *dl_b, u64 tsk_bw, int cpus) 288 { 289 dl_b->total_bw -= tsk_bw; 290 __dl_update(dl_b, (s32)tsk_bw / cpus); 291 } 292 293 static inline 294 void __dl_add(struct dl_bw *dl_b, u64 tsk_bw, int cpus) 295 { 296 dl_b->total_bw += tsk_bw; 297 __dl_update(dl_b, -((s32)tsk_bw / cpus)); 298 } 299 300 static inline 301 bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw) 302 { 303 return dl_b->bw != -1 && 304 dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw; 305 } 306 307 extern void dl_change_utilization(struct task_struct *p, u64 new_bw); 308 extern void init_dl_bw(struct dl_bw *dl_b); 309 extern int sched_dl_global_validate(void); 310 extern void sched_dl_do_global(void); 311 extern int sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr); 312 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr); 313 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr); 314 extern bool __checkparam_dl(const struct sched_attr *attr); 315 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr); 316 extern int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed); 317 extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 318 extern bool dl_cpu_busy(unsigned int cpu); 319 320 #ifdef CONFIG_CGROUP_SCHED 321 322 #include <linux/cgroup.h> 323 #include <linux/psi.h> 324 325 struct cfs_rq; 326 struct rt_rq; 327 328 extern struct list_head task_groups; 329 330 struct cfs_bandwidth { 331 #ifdef CONFIG_CFS_BANDWIDTH 332 raw_spinlock_t lock; 333 ktime_t period; 334 u64 quota; 335 u64 runtime; 336 s64 hierarchical_quota; 337 u64 runtime_expires; 338 int expires_seq; 339 340 short idle; 341 short period_active; 342 struct hrtimer period_timer; 343 struct hrtimer slack_timer; 344 struct list_head throttled_cfs_rq; 345 346 /* Statistics: */ 347 int nr_periods; 348 int nr_throttled; 349 u64 throttled_time; 350 351 bool distribute_running; 352 #endif 353 }; 354 355 /* Task group related information */ 356 struct task_group { 357 struct cgroup_subsys_state css; 358 359 #ifdef CONFIG_FAIR_GROUP_SCHED 360 /* schedulable entities of this group on each CPU */ 361 struct sched_entity **se; 362 /* runqueue "owned" by this group on each CPU */ 363 struct cfs_rq **cfs_rq; 364 unsigned long shares; 365 366 #ifdef CONFIG_SMP 367 /* 368 * load_avg can be heavily contended at clock tick time, so put 369 * it in its own cacheline separated from the fields above which 370 * will also be accessed at each tick. 371 */ 372 atomic_long_t load_avg ____cacheline_aligned; 373 #endif 374 #endif 375 376 #ifdef CONFIG_RT_GROUP_SCHED 377 struct sched_rt_entity **rt_se; 378 struct rt_rq **rt_rq; 379 380 struct rt_bandwidth rt_bandwidth; 381 #endif 382 383 struct rcu_head rcu; 384 struct list_head list; 385 386 struct task_group *parent; 387 struct list_head siblings; 388 struct list_head children; 389 390 #ifdef CONFIG_SCHED_AUTOGROUP 391 struct autogroup *autogroup; 392 #endif 393 394 struct cfs_bandwidth cfs_bandwidth; 395 }; 396 397 #ifdef CONFIG_FAIR_GROUP_SCHED 398 #define ROOT_TASK_GROUP_LOAD NICE_0_LOAD 399 400 /* 401 * A weight of 0 or 1 can cause arithmetics problems. 402 * A weight of a cfs_rq is the sum of weights of which entities 403 * are queued on this cfs_rq, so a weight of a entity should not be 404 * too large, so as the shares value of a task group. 405 * (The default weight is 1024 - so there's no practical 406 * limitation from this.) 407 */ 408 #define MIN_SHARES (1UL << 1) 409 #define MAX_SHARES (1UL << 18) 410 #endif 411 412 typedef int (*tg_visitor)(struct task_group *, void *); 413 414 extern int walk_tg_tree_from(struct task_group *from, 415 tg_visitor down, tg_visitor up, void *data); 416 417 /* 418 * Iterate the full tree, calling @down when first entering a node and @up when 419 * leaving it for the final time. 420 * 421 * Caller must hold rcu_lock or sufficient equivalent. 422 */ 423 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data) 424 { 425 return walk_tg_tree_from(&root_task_group, down, up, data); 426 } 427 428 extern int tg_nop(struct task_group *tg, void *data); 429 430 extern void free_fair_sched_group(struct task_group *tg); 431 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent); 432 extern void online_fair_sched_group(struct task_group *tg); 433 extern void unregister_fair_sched_group(struct task_group *tg); 434 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, 435 struct sched_entity *se, int cpu, 436 struct sched_entity *parent); 437 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b); 438 439 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b); 440 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b); 441 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq); 442 443 extern void free_rt_sched_group(struct task_group *tg); 444 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent); 445 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, 446 struct sched_rt_entity *rt_se, int cpu, 447 struct sched_rt_entity *parent); 448 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us); 449 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us); 450 extern long sched_group_rt_runtime(struct task_group *tg); 451 extern long sched_group_rt_period(struct task_group *tg); 452 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk); 453 454 extern struct task_group *sched_create_group(struct task_group *parent); 455 extern void sched_online_group(struct task_group *tg, 456 struct task_group *parent); 457 extern void sched_destroy_group(struct task_group *tg); 458 extern void sched_offline_group(struct task_group *tg); 459 460 extern void sched_move_task(struct task_struct *tsk); 461 462 #ifdef CONFIG_FAIR_GROUP_SCHED 463 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); 464 465 #ifdef CONFIG_SMP 466 extern void set_task_rq_fair(struct sched_entity *se, 467 struct cfs_rq *prev, struct cfs_rq *next); 468 #else /* !CONFIG_SMP */ 469 static inline void set_task_rq_fair(struct sched_entity *se, 470 struct cfs_rq *prev, struct cfs_rq *next) { } 471 #endif /* CONFIG_SMP */ 472 #endif /* CONFIG_FAIR_GROUP_SCHED */ 473 474 #else /* CONFIG_CGROUP_SCHED */ 475 476 struct cfs_bandwidth { }; 477 478 #endif /* CONFIG_CGROUP_SCHED */ 479 480 /* CFS-related fields in a runqueue */ 481 struct cfs_rq { 482 struct load_weight load; 483 unsigned long runnable_weight; 484 unsigned int nr_running; 485 unsigned int h_nr_running; 486 487 u64 exec_clock; 488 u64 min_vruntime; 489 #ifndef CONFIG_64BIT 490 u64 min_vruntime_copy; 491 #endif 492 493 struct rb_root_cached tasks_timeline; 494 495 /* 496 * 'curr' points to currently running entity on this cfs_rq. 497 * It is set to NULL otherwise (i.e when none are currently running). 498 */ 499 struct sched_entity *curr; 500 struct sched_entity *next; 501 struct sched_entity *last; 502 struct sched_entity *skip; 503 504 #ifdef CONFIG_SCHED_DEBUG 505 unsigned int nr_spread_over; 506 #endif 507 508 #ifdef CONFIG_SMP 509 /* 510 * CFS load tracking 511 */ 512 struct sched_avg avg; 513 #ifndef CONFIG_64BIT 514 u64 load_last_update_time_copy; 515 #endif 516 struct { 517 raw_spinlock_t lock ____cacheline_aligned; 518 int nr; 519 unsigned long load_avg; 520 unsigned long util_avg; 521 unsigned long runnable_sum; 522 } removed; 523 524 #ifdef CONFIG_FAIR_GROUP_SCHED 525 unsigned long tg_load_avg_contrib; 526 long propagate; 527 long prop_runnable_sum; 528 529 /* 530 * h_load = weight * f(tg) 531 * 532 * Where f(tg) is the recursive weight fraction assigned to 533 * this group. 534 */ 535 unsigned long h_load; 536 u64 last_h_load_update; 537 struct sched_entity *h_load_next; 538 #endif /* CONFIG_FAIR_GROUP_SCHED */ 539 #endif /* CONFIG_SMP */ 540 541 #ifdef CONFIG_FAIR_GROUP_SCHED 542 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */ 543 544 /* 545 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in 546 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities 547 * (like users, containers etc.) 548 * 549 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU. 550 * This list is used during load balance. 551 */ 552 int on_list; 553 struct list_head leaf_cfs_rq_list; 554 struct task_group *tg; /* group that "owns" this runqueue */ 555 556 #ifdef CONFIG_CFS_BANDWIDTH 557 int runtime_enabled; 558 int expires_seq; 559 u64 runtime_expires; 560 s64 runtime_remaining; 561 562 u64 throttled_clock; 563 u64 throttled_clock_task; 564 u64 throttled_clock_task_time; 565 int throttled; 566 int throttle_count; 567 struct list_head throttled_list; 568 #endif /* CONFIG_CFS_BANDWIDTH */ 569 #endif /* CONFIG_FAIR_GROUP_SCHED */ 570 }; 571 572 static inline int rt_bandwidth_enabled(void) 573 { 574 return sysctl_sched_rt_runtime >= 0; 575 } 576 577 /* RT IPI pull logic requires IRQ_WORK */ 578 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP) 579 # define HAVE_RT_PUSH_IPI 580 #endif 581 582 /* Real-Time classes' related field in a runqueue: */ 583 struct rt_rq { 584 struct rt_prio_array active; 585 unsigned int rt_nr_running; 586 unsigned int rr_nr_running; 587 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED 588 struct { 589 int curr; /* highest queued rt task prio */ 590 #ifdef CONFIG_SMP 591 int next; /* next highest */ 592 #endif 593 } highest_prio; 594 #endif 595 #ifdef CONFIG_SMP 596 unsigned long rt_nr_migratory; 597 unsigned long rt_nr_total; 598 int overloaded; 599 struct plist_head pushable_tasks; 600 601 #endif /* CONFIG_SMP */ 602 int rt_queued; 603 604 int rt_throttled; 605 u64 rt_time; 606 u64 rt_runtime; 607 /* Nests inside the rq lock: */ 608 raw_spinlock_t rt_runtime_lock; 609 610 #ifdef CONFIG_RT_GROUP_SCHED 611 unsigned long rt_nr_boosted; 612 613 struct rq *rq; 614 struct task_group *tg; 615 #endif 616 }; 617 618 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq) 619 { 620 return rt_rq->rt_queued && rt_rq->rt_nr_running; 621 } 622 623 /* Deadline class' related fields in a runqueue */ 624 struct dl_rq { 625 /* runqueue is an rbtree, ordered by deadline */ 626 struct rb_root_cached root; 627 628 unsigned long dl_nr_running; 629 630 #ifdef CONFIG_SMP 631 /* 632 * Deadline values of the currently executing and the 633 * earliest ready task on this rq. Caching these facilitates 634 * the decision wether or not a ready but not running task 635 * should migrate somewhere else. 636 */ 637 struct { 638 u64 curr; 639 u64 next; 640 } earliest_dl; 641 642 unsigned long dl_nr_migratory; 643 int overloaded; 644 645 /* 646 * Tasks on this rq that can be pushed away. They are kept in 647 * an rb-tree, ordered by tasks' deadlines, with caching 648 * of the leftmost (earliest deadline) element. 649 */ 650 struct rb_root_cached pushable_dl_tasks_root; 651 #else 652 struct dl_bw dl_bw; 653 #endif 654 /* 655 * "Active utilization" for this runqueue: increased when a 656 * task wakes up (becomes TASK_RUNNING) and decreased when a 657 * task blocks 658 */ 659 u64 running_bw; 660 661 /* 662 * Utilization of the tasks "assigned" to this runqueue (including 663 * the tasks that are in runqueue and the tasks that executed on this 664 * CPU and blocked). Increased when a task moves to this runqueue, and 665 * decreased when the task moves away (migrates, changes scheduling 666 * policy, or terminates). 667 * This is needed to compute the "inactive utilization" for the 668 * runqueue (inactive utilization = this_bw - running_bw). 669 */ 670 u64 this_bw; 671 u64 extra_bw; 672 673 /* 674 * Inverse of the fraction of CPU utilization that can be reclaimed 675 * by the GRUB algorithm. 676 */ 677 u64 bw_ratio; 678 }; 679 680 #ifdef CONFIG_FAIR_GROUP_SCHED 681 /* An entity is a task if it doesn't "own" a runqueue */ 682 #define entity_is_task(se) (!se->my_q) 683 #else 684 #define entity_is_task(se) 1 685 #endif 686 687 #ifdef CONFIG_SMP 688 /* 689 * XXX we want to get rid of these helpers and use the full load resolution. 690 */ 691 static inline long se_weight(struct sched_entity *se) 692 { 693 return scale_load_down(se->load.weight); 694 } 695 696 static inline long se_runnable(struct sched_entity *se) 697 { 698 return scale_load_down(se->runnable_weight); 699 } 700 701 static inline bool sched_asym_prefer(int a, int b) 702 { 703 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b); 704 } 705 706 /* 707 * We add the notion of a root-domain which will be used to define per-domain 708 * variables. Each exclusive cpuset essentially defines an island domain by 709 * fully partitioning the member CPUs from any other cpuset. Whenever a new 710 * exclusive cpuset is created, we also create and attach a new root-domain 711 * object. 712 * 713 */ 714 struct root_domain { 715 atomic_t refcount; 716 atomic_t rto_count; 717 struct rcu_head rcu; 718 cpumask_var_t span; 719 cpumask_var_t online; 720 721 /* 722 * Indicate pullable load on at least one CPU, e.g: 723 * - More than one runnable task 724 * - Running task is misfit 725 */ 726 int overload; 727 728 /* 729 * The bit corresponding to a CPU gets set here if such CPU has more 730 * than one runnable -deadline task (as it is below for RT tasks). 731 */ 732 cpumask_var_t dlo_mask; 733 atomic_t dlo_count; 734 struct dl_bw dl_bw; 735 struct cpudl cpudl; 736 737 #ifdef HAVE_RT_PUSH_IPI 738 /* 739 * For IPI pull requests, loop across the rto_mask. 740 */ 741 struct irq_work rto_push_work; 742 raw_spinlock_t rto_lock; 743 /* These are only updated and read within rto_lock */ 744 int rto_loop; 745 int rto_cpu; 746 /* These atomics are updated outside of a lock */ 747 atomic_t rto_loop_next; 748 atomic_t rto_loop_start; 749 #endif 750 /* 751 * The "RT overload" flag: it gets set if a CPU has more than 752 * one runnable RT task. 753 */ 754 cpumask_var_t rto_mask; 755 struct cpupri cpupri; 756 757 unsigned long max_cpu_capacity; 758 }; 759 760 extern struct root_domain def_root_domain; 761 extern struct mutex sched_domains_mutex; 762 763 extern void init_defrootdomain(void); 764 extern int sched_init_domains(const struct cpumask *cpu_map); 765 extern void rq_attach_root(struct rq *rq, struct root_domain *rd); 766 extern void sched_get_rd(struct root_domain *rd); 767 extern void sched_put_rd(struct root_domain *rd); 768 769 #ifdef HAVE_RT_PUSH_IPI 770 extern void rto_push_irq_work_func(struct irq_work *work); 771 #endif 772 #endif /* CONFIG_SMP */ 773 774 /* 775 * This is the main, per-CPU runqueue data structure. 776 * 777 * Locking rule: those places that want to lock multiple runqueues 778 * (such as the load balancing or the thread migration code), lock 779 * acquire operations must be ordered by ascending &runqueue. 780 */ 781 struct rq { 782 /* runqueue lock: */ 783 raw_spinlock_t lock; 784 785 /* 786 * nr_running and cpu_load should be in the same cacheline because 787 * remote CPUs use both these fields when doing load calculation. 788 */ 789 unsigned int nr_running; 790 #ifdef CONFIG_NUMA_BALANCING 791 unsigned int nr_numa_running; 792 unsigned int nr_preferred_running; 793 unsigned int numa_migrate_on; 794 #endif 795 #define CPU_LOAD_IDX_MAX 5 796 unsigned long cpu_load[CPU_LOAD_IDX_MAX]; 797 #ifdef CONFIG_NO_HZ_COMMON 798 #ifdef CONFIG_SMP 799 unsigned long last_load_update_tick; 800 unsigned long last_blocked_load_update_tick; 801 unsigned int has_blocked_load; 802 #endif /* CONFIG_SMP */ 803 unsigned int nohz_tick_stopped; 804 atomic_t nohz_flags; 805 #endif /* CONFIG_NO_HZ_COMMON */ 806 807 /* capture load from *all* tasks on this CPU: */ 808 struct load_weight load; 809 unsigned long nr_load_updates; 810 u64 nr_switches; 811 812 struct cfs_rq cfs; 813 struct rt_rq rt; 814 struct dl_rq dl; 815 816 #ifdef CONFIG_FAIR_GROUP_SCHED 817 /* list of leaf cfs_rq on this CPU: */ 818 struct list_head leaf_cfs_rq_list; 819 struct list_head *tmp_alone_branch; 820 #endif /* CONFIG_FAIR_GROUP_SCHED */ 821 822 /* 823 * This is part of a global counter where only the total sum 824 * over all CPUs matters. A task can increase this counter on 825 * one CPU and if it got migrated afterwards it may decrease 826 * it on another CPU. Always updated under the runqueue lock: 827 */ 828 unsigned long nr_uninterruptible; 829 830 struct task_struct *curr; 831 struct task_struct *idle; 832 struct task_struct *stop; 833 unsigned long next_balance; 834 struct mm_struct *prev_mm; 835 836 unsigned int clock_update_flags; 837 u64 clock; 838 u64 clock_task; 839 840 atomic_t nr_iowait; 841 842 #ifdef CONFIG_SMP 843 struct root_domain *rd; 844 struct sched_domain *sd; 845 846 unsigned long cpu_capacity; 847 unsigned long cpu_capacity_orig; 848 849 struct callback_head *balance_callback; 850 851 unsigned char idle_balance; 852 853 unsigned long misfit_task_load; 854 855 /* For active balancing */ 856 int active_balance; 857 int push_cpu; 858 struct cpu_stop_work active_balance_work; 859 860 /* CPU of this runqueue: */ 861 int cpu; 862 int online; 863 864 struct list_head cfs_tasks; 865 866 struct sched_avg avg_rt; 867 struct sched_avg avg_dl; 868 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 869 struct sched_avg avg_irq; 870 #endif 871 u64 idle_stamp; 872 u64 avg_idle; 873 874 /* This is used to determine avg_idle's max value */ 875 u64 max_idle_balance_cost; 876 #endif 877 878 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 879 u64 prev_irq_time; 880 #endif 881 #ifdef CONFIG_PARAVIRT 882 u64 prev_steal_time; 883 #endif 884 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING 885 u64 prev_steal_time_rq; 886 #endif 887 888 /* calc_load related fields */ 889 unsigned long calc_load_update; 890 long calc_load_active; 891 892 #ifdef CONFIG_SCHED_HRTICK 893 #ifdef CONFIG_SMP 894 int hrtick_csd_pending; 895 call_single_data_t hrtick_csd; 896 #endif 897 struct hrtimer hrtick_timer; 898 #endif 899 900 #ifdef CONFIG_SCHEDSTATS 901 /* latency stats */ 902 struct sched_info rq_sched_info; 903 unsigned long long rq_cpu_time; 904 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */ 905 906 /* sys_sched_yield() stats */ 907 unsigned int yld_count; 908 909 /* schedule() stats */ 910 unsigned int sched_count; 911 unsigned int sched_goidle; 912 913 /* try_to_wake_up() stats */ 914 unsigned int ttwu_count; 915 unsigned int ttwu_local; 916 #endif 917 918 #ifdef CONFIG_SMP 919 struct llist_head wake_list; 920 #endif 921 922 #ifdef CONFIG_CPU_IDLE 923 /* Must be inspected within a rcu lock section */ 924 struct cpuidle_state *idle_state; 925 #endif 926 }; 927 928 static inline int cpu_of(struct rq *rq) 929 { 930 #ifdef CONFIG_SMP 931 return rq->cpu; 932 #else 933 return 0; 934 #endif 935 } 936 937 938 #ifdef CONFIG_SCHED_SMT 939 940 extern struct static_key_false sched_smt_present; 941 942 extern void __update_idle_core(struct rq *rq); 943 944 static inline void update_idle_core(struct rq *rq) 945 { 946 if (static_branch_unlikely(&sched_smt_present)) 947 __update_idle_core(rq); 948 } 949 950 #else 951 static inline void update_idle_core(struct rq *rq) { } 952 #endif 953 954 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); 955 956 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) 957 #define this_rq() this_cpu_ptr(&runqueues) 958 #define task_rq(p) cpu_rq(task_cpu(p)) 959 #define cpu_curr(cpu) (cpu_rq(cpu)->curr) 960 #define raw_rq() raw_cpu_ptr(&runqueues) 961 962 extern void update_rq_clock(struct rq *rq); 963 964 static inline u64 __rq_clock_broken(struct rq *rq) 965 { 966 return READ_ONCE(rq->clock); 967 } 968 969 /* 970 * rq::clock_update_flags bits 971 * 972 * %RQCF_REQ_SKIP - will request skipping of clock update on the next 973 * call to __schedule(). This is an optimisation to avoid 974 * neighbouring rq clock updates. 975 * 976 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is 977 * in effect and calls to update_rq_clock() are being ignored. 978 * 979 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been 980 * made to update_rq_clock() since the last time rq::lock was pinned. 981 * 982 * If inside of __schedule(), clock_update_flags will have been 983 * shifted left (a left shift is a cheap operation for the fast path 984 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use, 985 * 986 * if (rq-clock_update_flags >= RQCF_UPDATED) 987 * 988 * to check if %RQCF_UPADTED is set. It'll never be shifted more than 989 * one position though, because the next rq_unpin_lock() will shift it 990 * back. 991 */ 992 #define RQCF_REQ_SKIP 0x01 993 #define RQCF_ACT_SKIP 0x02 994 #define RQCF_UPDATED 0x04 995 996 static inline void assert_clock_updated(struct rq *rq) 997 { 998 /* 999 * The only reason for not seeing a clock update since the 1000 * last rq_pin_lock() is if we're currently skipping updates. 1001 */ 1002 SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP); 1003 } 1004 1005 static inline u64 rq_clock(struct rq *rq) 1006 { 1007 lockdep_assert_held(&rq->lock); 1008 assert_clock_updated(rq); 1009 1010 return rq->clock; 1011 } 1012 1013 static inline u64 rq_clock_task(struct rq *rq) 1014 { 1015 lockdep_assert_held(&rq->lock); 1016 assert_clock_updated(rq); 1017 1018 return rq->clock_task; 1019 } 1020 1021 static inline void rq_clock_skip_update(struct rq *rq) 1022 { 1023 lockdep_assert_held(&rq->lock); 1024 rq->clock_update_flags |= RQCF_REQ_SKIP; 1025 } 1026 1027 /* 1028 * See rt task throttling, which is the only time a skip 1029 * request is cancelled. 1030 */ 1031 static inline void rq_clock_cancel_skipupdate(struct rq *rq) 1032 { 1033 lockdep_assert_held(&rq->lock); 1034 rq->clock_update_flags &= ~RQCF_REQ_SKIP; 1035 } 1036 1037 struct rq_flags { 1038 unsigned long flags; 1039 struct pin_cookie cookie; 1040 #ifdef CONFIG_SCHED_DEBUG 1041 /* 1042 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the 1043 * current pin context is stashed here in case it needs to be 1044 * restored in rq_repin_lock(). 1045 */ 1046 unsigned int clock_update_flags; 1047 #endif 1048 }; 1049 1050 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf) 1051 { 1052 rf->cookie = lockdep_pin_lock(&rq->lock); 1053 1054 #ifdef CONFIG_SCHED_DEBUG 1055 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 1056 rf->clock_update_flags = 0; 1057 #endif 1058 } 1059 1060 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf) 1061 { 1062 #ifdef CONFIG_SCHED_DEBUG 1063 if (rq->clock_update_flags > RQCF_ACT_SKIP) 1064 rf->clock_update_flags = RQCF_UPDATED; 1065 #endif 1066 1067 lockdep_unpin_lock(&rq->lock, rf->cookie); 1068 } 1069 1070 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf) 1071 { 1072 lockdep_repin_lock(&rq->lock, rf->cookie); 1073 1074 #ifdef CONFIG_SCHED_DEBUG 1075 /* 1076 * Restore the value we stashed in @rf for this pin context. 1077 */ 1078 rq->clock_update_flags |= rf->clock_update_flags; 1079 #endif 1080 } 1081 1082 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1083 __acquires(rq->lock); 1084 1085 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1086 __acquires(p->pi_lock) 1087 __acquires(rq->lock); 1088 1089 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf) 1090 __releases(rq->lock) 1091 { 1092 rq_unpin_lock(rq, rf); 1093 raw_spin_unlock(&rq->lock); 1094 } 1095 1096 static inline void 1097 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) 1098 __releases(rq->lock) 1099 __releases(p->pi_lock) 1100 { 1101 rq_unpin_lock(rq, rf); 1102 raw_spin_unlock(&rq->lock); 1103 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); 1104 } 1105 1106 static inline void 1107 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) 1108 __acquires(rq->lock) 1109 { 1110 raw_spin_lock_irqsave(&rq->lock, rf->flags); 1111 rq_pin_lock(rq, rf); 1112 } 1113 1114 static inline void 1115 rq_lock_irq(struct rq *rq, struct rq_flags *rf) 1116 __acquires(rq->lock) 1117 { 1118 raw_spin_lock_irq(&rq->lock); 1119 rq_pin_lock(rq, rf); 1120 } 1121 1122 static inline void 1123 rq_lock(struct rq *rq, struct rq_flags *rf) 1124 __acquires(rq->lock) 1125 { 1126 raw_spin_lock(&rq->lock); 1127 rq_pin_lock(rq, rf); 1128 } 1129 1130 static inline void 1131 rq_relock(struct rq *rq, struct rq_flags *rf) 1132 __acquires(rq->lock) 1133 { 1134 raw_spin_lock(&rq->lock); 1135 rq_repin_lock(rq, rf); 1136 } 1137 1138 static inline void 1139 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf) 1140 __releases(rq->lock) 1141 { 1142 rq_unpin_lock(rq, rf); 1143 raw_spin_unlock_irqrestore(&rq->lock, rf->flags); 1144 } 1145 1146 static inline void 1147 rq_unlock_irq(struct rq *rq, struct rq_flags *rf) 1148 __releases(rq->lock) 1149 { 1150 rq_unpin_lock(rq, rf); 1151 raw_spin_unlock_irq(&rq->lock); 1152 } 1153 1154 static inline void 1155 rq_unlock(struct rq *rq, struct rq_flags *rf) 1156 __releases(rq->lock) 1157 { 1158 rq_unpin_lock(rq, rf); 1159 raw_spin_unlock(&rq->lock); 1160 } 1161 1162 static inline struct rq * 1163 this_rq_lock_irq(struct rq_flags *rf) 1164 __acquires(rq->lock) 1165 { 1166 struct rq *rq; 1167 1168 local_irq_disable(); 1169 rq = this_rq(); 1170 rq_lock(rq, rf); 1171 return rq; 1172 } 1173 1174 #ifdef CONFIG_NUMA 1175 enum numa_topology_type { 1176 NUMA_DIRECT, 1177 NUMA_GLUELESS_MESH, 1178 NUMA_BACKPLANE, 1179 }; 1180 extern enum numa_topology_type sched_numa_topology_type; 1181 extern int sched_max_numa_distance; 1182 extern bool find_numa_distance(int distance); 1183 #endif 1184 1185 #ifdef CONFIG_NUMA 1186 extern void sched_init_numa(void); 1187 extern void sched_domains_numa_masks_set(unsigned int cpu); 1188 extern void sched_domains_numa_masks_clear(unsigned int cpu); 1189 #else 1190 static inline void sched_init_numa(void) { } 1191 static inline void sched_domains_numa_masks_set(unsigned int cpu) { } 1192 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { } 1193 #endif 1194 1195 #ifdef CONFIG_NUMA_BALANCING 1196 /* The regions in numa_faults array from task_struct */ 1197 enum numa_faults_stats { 1198 NUMA_MEM = 0, 1199 NUMA_CPU, 1200 NUMA_MEMBUF, 1201 NUMA_CPUBUF 1202 }; 1203 extern void sched_setnuma(struct task_struct *p, int node); 1204 extern int migrate_task_to(struct task_struct *p, int cpu); 1205 extern int migrate_swap(struct task_struct *p, struct task_struct *t, 1206 int cpu, int scpu); 1207 extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p); 1208 #else 1209 static inline void 1210 init_numa_balancing(unsigned long clone_flags, struct task_struct *p) 1211 { 1212 } 1213 #endif /* CONFIG_NUMA_BALANCING */ 1214 1215 #ifdef CONFIG_SMP 1216 1217 static inline void 1218 queue_balance_callback(struct rq *rq, 1219 struct callback_head *head, 1220 void (*func)(struct rq *rq)) 1221 { 1222 lockdep_assert_held(&rq->lock); 1223 1224 if (unlikely(head->next)) 1225 return; 1226 1227 head->func = (void (*)(struct callback_head *))func; 1228 head->next = rq->balance_callback; 1229 rq->balance_callback = head; 1230 } 1231 1232 extern void sched_ttwu_pending(void); 1233 1234 #define rcu_dereference_check_sched_domain(p) \ 1235 rcu_dereference_check((p), \ 1236 lockdep_is_held(&sched_domains_mutex)) 1237 1238 /* 1239 * The domain tree (rq->sd) is protected by RCU's quiescent state transition. 1240 * See detach_destroy_domains: synchronize_sched for details. 1241 * 1242 * The domain tree of any CPU may only be accessed from within 1243 * preempt-disabled sections. 1244 */ 1245 #define for_each_domain(cpu, __sd) \ 1246 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \ 1247 __sd; __sd = __sd->parent) 1248 1249 #define for_each_lower_domain(sd) for (; sd; sd = sd->child) 1250 1251 /** 1252 * highest_flag_domain - Return highest sched_domain containing flag. 1253 * @cpu: The CPU whose highest level of sched domain is to 1254 * be returned. 1255 * @flag: The flag to check for the highest sched_domain 1256 * for the given CPU. 1257 * 1258 * Returns the highest sched_domain of a CPU which contains the given flag. 1259 */ 1260 static inline struct sched_domain *highest_flag_domain(int cpu, int flag) 1261 { 1262 struct sched_domain *sd, *hsd = NULL; 1263 1264 for_each_domain(cpu, sd) { 1265 if (!(sd->flags & flag)) 1266 break; 1267 hsd = sd; 1268 } 1269 1270 return hsd; 1271 } 1272 1273 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) 1274 { 1275 struct sched_domain *sd; 1276 1277 for_each_domain(cpu, sd) { 1278 if (sd->flags & flag) 1279 break; 1280 } 1281 1282 return sd; 1283 } 1284 1285 DECLARE_PER_CPU(struct sched_domain *, sd_llc); 1286 DECLARE_PER_CPU(int, sd_llc_size); 1287 DECLARE_PER_CPU(int, sd_llc_id); 1288 DECLARE_PER_CPU(struct sched_domain_shared *, sd_llc_shared); 1289 DECLARE_PER_CPU(struct sched_domain *, sd_numa); 1290 DECLARE_PER_CPU(struct sched_domain *, sd_asym); 1291 extern struct static_key_false sched_asym_cpucapacity; 1292 1293 struct sched_group_capacity { 1294 atomic_t ref; 1295 /* 1296 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity 1297 * for a single CPU. 1298 */ 1299 unsigned long capacity; 1300 unsigned long min_capacity; /* Min per-CPU capacity in group */ 1301 unsigned long max_capacity; /* Max per-CPU capacity in group */ 1302 unsigned long next_update; 1303 int imbalance; /* XXX unrelated to capacity but shared group state */ 1304 1305 #ifdef CONFIG_SCHED_DEBUG 1306 int id; 1307 #endif 1308 1309 unsigned long cpumask[0]; /* Balance mask */ 1310 }; 1311 1312 struct sched_group { 1313 struct sched_group *next; /* Must be a circular list */ 1314 atomic_t ref; 1315 1316 unsigned int group_weight; 1317 struct sched_group_capacity *sgc; 1318 int asym_prefer_cpu; /* CPU of highest priority in group */ 1319 1320 /* 1321 * The CPUs this group covers. 1322 * 1323 * NOTE: this field is variable length. (Allocated dynamically 1324 * by attaching extra space to the end of the structure, 1325 * depending on how many CPUs the kernel has booted up with) 1326 */ 1327 unsigned long cpumask[0]; 1328 }; 1329 1330 static inline struct cpumask *sched_group_span(struct sched_group *sg) 1331 { 1332 return to_cpumask(sg->cpumask); 1333 } 1334 1335 /* 1336 * See build_balance_mask(). 1337 */ 1338 static inline struct cpumask *group_balance_mask(struct sched_group *sg) 1339 { 1340 return to_cpumask(sg->sgc->cpumask); 1341 } 1342 1343 /** 1344 * group_first_cpu - Returns the first CPU in the cpumask of a sched_group. 1345 * @group: The group whose first CPU is to be returned. 1346 */ 1347 static inline unsigned int group_first_cpu(struct sched_group *group) 1348 { 1349 return cpumask_first(sched_group_span(group)); 1350 } 1351 1352 extern int group_balance_cpu(struct sched_group *sg); 1353 1354 #if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL) 1355 void register_sched_domain_sysctl(void); 1356 void dirty_sched_domain_sysctl(int cpu); 1357 void unregister_sched_domain_sysctl(void); 1358 #else 1359 static inline void register_sched_domain_sysctl(void) 1360 { 1361 } 1362 static inline void dirty_sched_domain_sysctl(int cpu) 1363 { 1364 } 1365 static inline void unregister_sched_domain_sysctl(void) 1366 { 1367 } 1368 #endif 1369 1370 #else 1371 1372 static inline void sched_ttwu_pending(void) { } 1373 1374 #endif /* CONFIG_SMP */ 1375 1376 #include "stats.h" 1377 #include "autogroup.h" 1378 1379 #ifdef CONFIG_CGROUP_SCHED 1380 1381 /* 1382 * Return the group to which this tasks belongs. 1383 * 1384 * We cannot use task_css() and friends because the cgroup subsystem 1385 * changes that value before the cgroup_subsys::attach() method is called, 1386 * therefore we cannot pin it and might observe the wrong value. 1387 * 1388 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup 1389 * core changes this before calling sched_move_task(). 1390 * 1391 * Instead we use a 'copy' which is updated from sched_move_task() while 1392 * holding both task_struct::pi_lock and rq::lock. 1393 */ 1394 static inline struct task_group *task_group(struct task_struct *p) 1395 { 1396 return p->sched_task_group; 1397 } 1398 1399 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ 1400 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) 1401 { 1402 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED) 1403 struct task_group *tg = task_group(p); 1404 #endif 1405 1406 #ifdef CONFIG_FAIR_GROUP_SCHED 1407 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]); 1408 p->se.cfs_rq = tg->cfs_rq[cpu]; 1409 p->se.parent = tg->se[cpu]; 1410 #endif 1411 1412 #ifdef CONFIG_RT_GROUP_SCHED 1413 p->rt.rt_rq = tg->rt_rq[cpu]; 1414 p->rt.parent = tg->rt_se[cpu]; 1415 #endif 1416 } 1417 1418 #else /* CONFIG_CGROUP_SCHED */ 1419 1420 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } 1421 static inline struct task_group *task_group(struct task_struct *p) 1422 { 1423 return NULL; 1424 } 1425 1426 #endif /* CONFIG_CGROUP_SCHED */ 1427 1428 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) 1429 { 1430 set_task_rq(p, cpu); 1431 #ifdef CONFIG_SMP 1432 /* 1433 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be 1434 * successfuly executed on another CPU. We must ensure that updates of 1435 * per-task data have been completed by this moment. 1436 */ 1437 smp_wmb(); 1438 #ifdef CONFIG_THREAD_INFO_IN_TASK 1439 p->cpu = cpu; 1440 #else 1441 task_thread_info(p)->cpu = cpu; 1442 #endif 1443 p->wake_cpu = cpu; 1444 #endif 1445 } 1446 1447 /* 1448 * Tunables that become constants when CONFIG_SCHED_DEBUG is off: 1449 */ 1450 #ifdef CONFIG_SCHED_DEBUG 1451 # include <linux/static_key.h> 1452 # define const_debug __read_mostly 1453 #else 1454 # define const_debug const 1455 #endif 1456 1457 #define SCHED_FEAT(name, enabled) \ 1458 __SCHED_FEAT_##name , 1459 1460 enum { 1461 #include "features.h" 1462 __SCHED_FEAT_NR, 1463 }; 1464 1465 #undef SCHED_FEAT 1466 1467 #if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL) 1468 1469 /* 1470 * To support run-time toggling of sched features, all the translation units 1471 * (but core.c) reference the sysctl_sched_features defined in core.c. 1472 */ 1473 extern const_debug unsigned int sysctl_sched_features; 1474 1475 #define SCHED_FEAT(name, enabled) \ 1476 static __always_inline bool static_branch_##name(struct static_key *key) \ 1477 { \ 1478 return static_key_##enabled(key); \ 1479 } 1480 1481 #include "features.h" 1482 #undef SCHED_FEAT 1483 1484 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR]; 1485 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x])) 1486 1487 #else /* !(SCHED_DEBUG && HAVE_JUMP_LABEL) */ 1488 1489 /* 1490 * Each translation unit has its own copy of sysctl_sched_features to allow 1491 * constants propagation at compile time and compiler optimization based on 1492 * features default. 1493 */ 1494 #define SCHED_FEAT(name, enabled) \ 1495 (1UL << __SCHED_FEAT_##name) * enabled | 1496 static const_debug __maybe_unused unsigned int sysctl_sched_features = 1497 #include "features.h" 1498 0; 1499 #undef SCHED_FEAT 1500 1501 #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) 1502 1503 #endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */ 1504 1505 extern struct static_key_false sched_numa_balancing; 1506 extern struct static_key_false sched_schedstats; 1507 1508 static inline u64 global_rt_period(void) 1509 { 1510 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC; 1511 } 1512 1513 static inline u64 global_rt_runtime(void) 1514 { 1515 if (sysctl_sched_rt_runtime < 0) 1516 return RUNTIME_INF; 1517 1518 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC; 1519 } 1520 1521 static inline int task_current(struct rq *rq, struct task_struct *p) 1522 { 1523 return rq->curr == p; 1524 } 1525 1526 static inline int task_running(struct rq *rq, struct task_struct *p) 1527 { 1528 #ifdef CONFIG_SMP 1529 return p->on_cpu; 1530 #else 1531 return task_current(rq, p); 1532 #endif 1533 } 1534 1535 static inline int task_on_rq_queued(struct task_struct *p) 1536 { 1537 return p->on_rq == TASK_ON_RQ_QUEUED; 1538 } 1539 1540 static inline int task_on_rq_migrating(struct task_struct *p) 1541 { 1542 return p->on_rq == TASK_ON_RQ_MIGRATING; 1543 } 1544 1545 /* 1546 * wake flags 1547 */ 1548 #define WF_SYNC 0x01 /* Waker goes to sleep after wakeup */ 1549 #define WF_FORK 0x02 /* Child wakeup after fork */ 1550 #define WF_MIGRATED 0x4 /* Internal use, task got migrated */ 1551 1552 /* 1553 * To aid in avoiding the subversion of "niceness" due to uneven distribution 1554 * of tasks with abnormal "nice" values across CPUs the contribution that 1555 * each task makes to its run queue's load is weighted according to its 1556 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a 1557 * scaled version of the new time slice allocation that they receive on time 1558 * slice expiry etc. 1559 */ 1560 1561 #define WEIGHT_IDLEPRIO 3 1562 #define WMULT_IDLEPRIO 1431655765 1563 1564 extern const int sched_prio_to_weight[40]; 1565 extern const u32 sched_prio_to_wmult[40]; 1566 1567 /* 1568 * {de,en}queue flags: 1569 * 1570 * DEQUEUE_SLEEP - task is no longer runnable 1571 * ENQUEUE_WAKEUP - task just became runnable 1572 * 1573 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks 1574 * are in a known state which allows modification. Such pairs 1575 * should preserve as much state as possible. 1576 * 1577 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location 1578 * in the runqueue. 1579 * 1580 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified) 1581 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline) 1582 * ENQUEUE_MIGRATED - the task was migrated during wakeup 1583 * 1584 */ 1585 1586 #define DEQUEUE_SLEEP 0x01 1587 #define DEQUEUE_SAVE 0x02 /* Matches ENQUEUE_RESTORE */ 1588 #define DEQUEUE_MOVE 0x04 /* Matches ENQUEUE_MOVE */ 1589 #define DEQUEUE_NOCLOCK 0x08 /* Matches ENQUEUE_NOCLOCK */ 1590 1591 #define ENQUEUE_WAKEUP 0x01 1592 #define ENQUEUE_RESTORE 0x02 1593 #define ENQUEUE_MOVE 0x04 1594 #define ENQUEUE_NOCLOCK 0x08 1595 1596 #define ENQUEUE_HEAD 0x10 1597 #define ENQUEUE_REPLENISH 0x20 1598 #ifdef CONFIG_SMP 1599 #define ENQUEUE_MIGRATED 0x40 1600 #else 1601 #define ENQUEUE_MIGRATED 0x00 1602 #endif 1603 1604 #define RETRY_TASK ((void *)-1UL) 1605 1606 struct sched_class { 1607 const struct sched_class *next; 1608 1609 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags); 1610 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags); 1611 void (*yield_task) (struct rq *rq); 1612 bool (*yield_to_task)(struct rq *rq, struct task_struct *p, bool preempt); 1613 1614 void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags); 1615 1616 /* 1617 * It is the responsibility of the pick_next_task() method that will 1618 * return the next task to call put_prev_task() on the @prev task or 1619 * something equivalent. 1620 * 1621 * May return RETRY_TASK when it finds a higher prio class has runnable 1622 * tasks. 1623 */ 1624 struct task_struct * (*pick_next_task)(struct rq *rq, 1625 struct task_struct *prev, 1626 struct rq_flags *rf); 1627 void (*put_prev_task)(struct rq *rq, struct task_struct *p); 1628 1629 #ifdef CONFIG_SMP 1630 int (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags); 1631 void (*migrate_task_rq)(struct task_struct *p, int new_cpu); 1632 1633 void (*task_woken)(struct rq *this_rq, struct task_struct *task); 1634 1635 void (*set_cpus_allowed)(struct task_struct *p, 1636 const struct cpumask *newmask); 1637 1638 void (*rq_online)(struct rq *rq); 1639 void (*rq_offline)(struct rq *rq); 1640 #endif 1641 1642 void (*set_curr_task)(struct rq *rq); 1643 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued); 1644 void (*task_fork)(struct task_struct *p); 1645 void (*task_dead)(struct task_struct *p); 1646 1647 /* 1648 * The switched_from() call is allowed to drop rq->lock, therefore we 1649 * cannot assume the switched_from/switched_to pair is serliazed by 1650 * rq->lock. They are however serialized by p->pi_lock. 1651 */ 1652 void (*switched_from)(struct rq *this_rq, struct task_struct *task); 1653 void (*switched_to) (struct rq *this_rq, struct task_struct *task); 1654 void (*prio_changed) (struct rq *this_rq, struct task_struct *task, 1655 int oldprio); 1656 1657 unsigned int (*get_rr_interval)(struct rq *rq, 1658 struct task_struct *task); 1659 1660 void (*update_curr)(struct rq *rq); 1661 1662 #define TASK_SET_GROUP 0 1663 #define TASK_MOVE_GROUP 1 1664 1665 #ifdef CONFIG_FAIR_GROUP_SCHED 1666 void (*task_change_group)(struct task_struct *p, int type); 1667 #endif 1668 }; 1669 1670 static inline void put_prev_task(struct rq *rq, struct task_struct *prev) 1671 { 1672 prev->sched_class->put_prev_task(rq, prev); 1673 } 1674 1675 static inline void set_curr_task(struct rq *rq, struct task_struct *curr) 1676 { 1677 curr->sched_class->set_curr_task(rq); 1678 } 1679 1680 #ifdef CONFIG_SMP 1681 #define sched_class_highest (&stop_sched_class) 1682 #else 1683 #define sched_class_highest (&dl_sched_class) 1684 #endif 1685 #define for_each_class(class) \ 1686 for (class = sched_class_highest; class; class = class->next) 1687 1688 extern const struct sched_class stop_sched_class; 1689 extern const struct sched_class dl_sched_class; 1690 extern const struct sched_class rt_sched_class; 1691 extern const struct sched_class fair_sched_class; 1692 extern const struct sched_class idle_sched_class; 1693 1694 1695 #ifdef CONFIG_SMP 1696 1697 extern void update_group_capacity(struct sched_domain *sd, int cpu); 1698 1699 extern void trigger_load_balance(struct rq *rq); 1700 1701 extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask); 1702 1703 #endif 1704 1705 #ifdef CONFIG_CPU_IDLE 1706 static inline void idle_set_state(struct rq *rq, 1707 struct cpuidle_state *idle_state) 1708 { 1709 rq->idle_state = idle_state; 1710 } 1711 1712 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 1713 { 1714 SCHED_WARN_ON(!rcu_read_lock_held()); 1715 1716 return rq->idle_state; 1717 } 1718 #else 1719 static inline void idle_set_state(struct rq *rq, 1720 struct cpuidle_state *idle_state) 1721 { 1722 } 1723 1724 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 1725 { 1726 return NULL; 1727 } 1728 #endif 1729 1730 extern void schedule_idle(void); 1731 1732 extern void sysrq_sched_debug_show(void); 1733 extern void sched_init_granularity(void); 1734 extern void update_max_interval(void); 1735 1736 extern void init_sched_dl_class(void); 1737 extern void init_sched_rt_class(void); 1738 extern void init_sched_fair_class(void); 1739 1740 extern void reweight_task(struct task_struct *p, int prio); 1741 1742 extern void resched_curr(struct rq *rq); 1743 extern void resched_cpu(int cpu); 1744 1745 extern struct rt_bandwidth def_rt_bandwidth; 1746 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime); 1747 1748 extern struct dl_bandwidth def_dl_bandwidth; 1749 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime); 1750 extern void init_dl_task_timer(struct sched_dl_entity *dl_se); 1751 extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se); 1752 extern void init_dl_rq_bw_ratio(struct dl_rq *dl_rq); 1753 1754 #define BW_SHIFT 20 1755 #define BW_UNIT (1 << BW_SHIFT) 1756 #define RATIO_SHIFT 8 1757 unsigned long to_ratio(u64 period, u64 runtime); 1758 1759 extern void init_entity_runnable_average(struct sched_entity *se); 1760 extern void post_init_entity_util_avg(struct sched_entity *se); 1761 1762 #ifdef CONFIG_NO_HZ_FULL 1763 extern bool sched_can_stop_tick(struct rq *rq); 1764 extern int __init sched_tick_offload_init(void); 1765 1766 /* 1767 * Tick may be needed by tasks in the runqueue depending on their policy and 1768 * requirements. If tick is needed, lets send the target an IPI to kick it out of 1769 * nohz mode if necessary. 1770 */ 1771 static inline void sched_update_tick_dependency(struct rq *rq) 1772 { 1773 int cpu; 1774 1775 if (!tick_nohz_full_enabled()) 1776 return; 1777 1778 cpu = cpu_of(rq); 1779 1780 if (!tick_nohz_full_cpu(cpu)) 1781 return; 1782 1783 if (sched_can_stop_tick(rq)) 1784 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED); 1785 else 1786 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED); 1787 } 1788 #else 1789 static inline int sched_tick_offload_init(void) { return 0; } 1790 static inline void sched_update_tick_dependency(struct rq *rq) { } 1791 #endif 1792 1793 static inline void add_nr_running(struct rq *rq, unsigned count) 1794 { 1795 unsigned prev_nr = rq->nr_running; 1796 1797 rq->nr_running = prev_nr + count; 1798 1799 if (prev_nr < 2 && rq->nr_running >= 2) { 1800 #ifdef CONFIG_SMP 1801 if (!READ_ONCE(rq->rd->overload)) 1802 WRITE_ONCE(rq->rd->overload, 1); 1803 #endif 1804 } 1805 1806 sched_update_tick_dependency(rq); 1807 } 1808 1809 static inline void sub_nr_running(struct rq *rq, unsigned count) 1810 { 1811 rq->nr_running -= count; 1812 /* Check if we still need preemption */ 1813 sched_update_tick_dependency(rq); 1814 } 1815 1816 extern void activate_task(struct rq *rq, struct task_struct *p, int flags); 1817 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags); 1818 1819 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags); 1820 1821 extern const_debug unsigned int sysctl_sched_nr_migrate; 1822 extern const_debug unsigned int sysctl_sched_migration_cost; 1823 1824 #ifdef CONFIG_SCHED_HRTICK 1825 1826 /* 1827 * Use hrtick when: 1828 * - enabled by features 1829 * - hrtimer is actually high res 1830 */ 1831 static inline int hrtick_enabled(struct rq *rq) 1832 { 1833 if (!sched_feat(HRTICK)) 1834 return 0; 1835 if (!cpu_active(cpu_of(rq))) 1836 return 0; 1837 return hrtimer_is_hres_active(&rq->hrtick_timer); 1838 } 1839 1840 void hrtick_start(struct rq *rq, u64 delay); 1841 1842 #else 1843 1844 static inline int hrtick_enabled(struct rq *rq) 1845 { 1846 return 0; 1847 } 1848 1849 #endif /* CONFIG_SCHED_HRTICK */ 1850 1851 #ifndef arch_scale_freq_capacity 1852 static __always_inline 1853 unsigned long arch_scale_freq_capacity(int cpu) 1854 { 1855 return SCHED_CAPACITY_SCALE; 1856 } 1857 #endif 1858 1859 #ifdef CONFIG_SMP 1860 #ifndef arch_scale_cpu_capacity 1861 static __always_inline 1862 unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu) 1863 { 1864 if (sd && (sd->flags & SD_SHARE_CPUCAPACITY) && (sd->span_weight > 1)) 1865 return sd->smt_gain / sd->span_weight; 1866 1867 return SCHED_CAPACITY_SCALE; 1868 } 1869 #endif 1870 #else 1871 #ifndef arch_scale_cpu_capacity 1872 static __always_inline 1873 unsigned long arch_scale_cpu_capacity(void __always_unused *sd, int cpu) 1874 { 1875 return SCHED_CAPACITY_SCALE; 1876 } 1877 #endif 1878 #endif 1879 1880 #ifdef CONFIG_SMP 1881 #ifdef CONFIG_PREEMPT 1882 1883 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2); 1884 1885 /* 1886 * fair double_lock_balance: Safely acquires both rq->locks in a fair 1887 * way at the expense of forcing extra atomic operations in all 1888 * invocations. This assures that the double_lock is acquired using the 1889 * same underlying policy as the spinlock_t on this architecture, which 1890 * reduces latency compared to the unfair variant below. However, it 1891 * also adds more overhead and therefore may reduce throughput. 1892 */ 1893 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 1894 __releases(this_rq->lock) 1895 __acquires(busiest->lock) 1896 __acquires(this_rq->lock) 1897 { 1898 raw_spin_unlock(&this_rq->lock); 1899 double_rq_lock(this_rq, busiest); 1900 1901 return 1; 1902 } 1903 1904 #else 1905 /* 1906 * Unfair double_lock_balance: Optimizes throughput at the expense of 1907 * latency by eliminating extra atomic operations when the locks are 1908 * already in proper order on entry. This favors lower CPU-ids and will 1909 * grant the double lock to lower CPUs over higher ids under contention, 1910 * regardless of entry order into the function. 1911 */ 1912 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 1913 __releases(this_rq->lock) 1914 __acquires(busiest->lock) 1915 __acquires(this_rq->lock) 1916 { 1917 int ret = 0; 1918 1919 if (unlikely(!raw_spin_trylock(&busiest->lock))) { 1920 if (busiest < this_rq) { 1921 raw_spin_unlock(&this_rq->lock); 1922 raw_spin_lock(&busiest->lock); 1923 raw_spin_lock_nested(&this_rq->lock, 1924 SINGLE_DEPTH_NESTING); 1925 ret = 1; 1926 } else 1927 raw_spin_lock_nested(&busiest->lock, 1928 SINGLE_DEPTH_NESTING); 1929 } 1930 return ret; 1931 } 1932 1933 #endif /* CONFIG_PREEMPT */ 1934 1935 /* 1936 * double_lock_balance - lock the busiest runqueue, this_rq is locked already. 1937 */ 1938 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest) 1939 { 1940 if (unlikely(!irqs_disabled())) { 1941 /* printk() doesn't work well under rq->lock */ 1942 raw_spin_unlock(&this_rq->lock); 1943 BUG_ON(1); 1944 } 1945 1946 return _double_lock_balance(this_rq, busiest); 1947 } 1948 1949 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest) 1950 __releases(busiest->lock) 1951 { 1952 raw_spin_unlock(&busiest->lock); 1953 lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_); 1954 } 1955 1956 static inline void double_lock(spinlock_t *l1, spinlock_t *l2) 1957 { 1958 if (l1 > l2) 1959 swap(l1, l2); 1960 1961 spin_lock(l1); 1962 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 1963 } 1964 1965 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2) 1966 { 1967 if (l1 > l2) 1968 swap(l1, l2); 1969 1970 spin_lock_irq(l1); 1971 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 1972 } 1973 1974 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2) 1975 { 1976 if (l1 > l2) 1977 swap(l1, l2); 1978 1979 raw_spin_lock(l1); 1980 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 1981 } 1982 1983 /* 1984 * double_rq_lock - safely lock two runqueues 1985 * 1986 * Note this does not disable interrupts like task_rq_lock, 1987 * you need to do so manually before calling. 1988 */ 1989 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2) 1990 __acquires(rq1->lock) 1991 __acquires(rq2->lock) 1992 { 1993 BUG_ON(!irqs_disabled()); 1994 if (rq1 == rq2) { 1995 raw_spin_lock(&rq1->lock); 1996 __acquire(rq2->lock); /* Fake it out ;) */ 1997 } else { 1998 if (rq1 < rq2) { 1999 raw_spin_lock(&rq1->lock); 2000 raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING); 2001 } else { 2002 raw_spin_lock(&rq2->lock); 2003 raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING); 2004 } 2005 } 2006 } 2007 2008 /* 2009 * double_rq_unlock - safely unlock two runqueues 2010 * 2011 * Note this does not restore interrupts like task_rq_unlock, 2012 * you need to do so manually after calling. 2013 */ 2014 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 2015 __releases(rq1->lock) 2016 __releases(rq2->lock) 2017 { 2018 raw_spin_unlock(&rq1->lock); 2019 if (rq1 != rq2) 2020 raw_spin_unlock(&rq2->lock); 2021 else 2022 __release(rq2->lock); 2023 } 2024 2025 extern void set_rq_online (struct rq *rq); 2026 extern void set_rq_offline(struct rq *rq); 2027 extern bool sched_smp_initialized; 2028 2029 #else /* CONFIG_SMP */ 2030 2031 /* 2032 * double_rq_lock - safely lock two runqueues 2033 * 2034 * Note this does not disable interrupts like task_rq_lock, 2035 * you need to do so manually before calling. 2036 */ 2037 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2) 2038 __acquires(rq1->lock) 2039 __acquires(rq2->lock) 2040 { 2041 BUG_ON(!irqs_disabled()); 2042 BUG_ON(rq1 != rq2); 2043 raw_spin_lock(&rq1->lock); 2044 __acquire(rq2->lock); /* Fake it out ;) */ 2045 } 2046 2047 /* 2048 * double_rq_unlock - safely unlock two runqueues 2049 * 2050 * Note this does not restore interrupts like task_rq_unlock, 2051 * you need to do so manually after calling. 2052 */ 2053 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 2054 __releases(rq1->lock) 2055 __releases(rq2->lock) 2056 { 2057 BUG_ON(rq1 != rq2); 2058 raw_spin_unlock(&rq1->lock); 2059 __release(rq2->lock); 2060 } 2061 2062 #endif 2063 2064 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq); 2065 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq); 2066 2067 #ifdef CONFIG_SCHED_DEBUG 2068 extern bool sched_debug_enabled; 2069 2070 extern void print_cfs_stats(struct seq_file *m, int cpu); 2071 extern void print_rt_stats(struct seq_file *m, int cpu); 2072 extern void print_dl_stats(struct seq_file *m, int cpu); 2073 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 2074 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq); 2075 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq); 2076 #ifdef CONFIG_NUMA_BALANCING 2077 extern void 2078 show_numa_stats(struct task_struct *p, struct seq_file *m); 2079 extern void 2080 print_numa_stats(struct seq_file *m, int node, unsigned long tsf, 2081 unsigned long tpf, unsigned long gsf, unsigned long gpf); 2082 #endif /* CONFIG_NUMA_BALANCING */ 2083 #endif /* CONFIG_SCHED_DEBUG */ 2084 2085 extern void init_cfs_rq(struct cfs_rq *cfs_rq); 2086 extern void init_rt_rq(struct rt_rq *rt_rq); 2087 extern void init_dl_rq(struct dl_rq *dl_rq); 2088 2089 extern void cfs_bandwidth_usage_inc(void); 2090 extern void cfs_bandwidth_usage_dec(void); 2091 2092 #ifdef CONFIG_NO_HZ_COMMON 2093 #define NOHZ_BALANCE_KICK_BIT 0 2094 #define NOHZ_STATS_KICK_BIT 1 2095 2096 #define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT) 2097 #define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT) 2098 2099 #define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK) 2100 2101 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags) 2102 2103 extern void nohz_balance_exit_idle(struct rq *rq); 2104 #else 2105 static inline void nohz_balance_exit_idle(struct rq *rq) { } 2106 #endif 2107 2108 2109 #ifdef CONFIG_SMP 2110 static inline 2111 void __dl_update(struct dl_bw *dl_b, s64 bw) 2112 { 2113 struct root_domain *rd = container_of(dl_b, struct root_domain, dl_bw); 2114 int i; 2115 2116 RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(), 2117 "sched RCU must be held"); 2118 for_each_cpu_and(i, rd->span, cpu_active_mask) { 2119 struct rq *rq = cpu_rq(i); 2120 2121 rq->dl.extra_bw += bw; 2122 } 2123 } 2124 #else 2125 static inline 2126 void __dl_update(struct dl_bw *dl_b, s64 bw) 2127 { 2128 struct dl_rq *dl = container_of(dl_b, struct dl_rq, dl_bw); 2129 2130 dl->extra_bw += bw; 2131 } 2132 #endif 2133 2134 2135 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 2136 struct irqtime { 2137 u64 total; 2138 u64 tick_delta; 2139 u64 irq_start_time; 2140 struct u64_stats_sync sync; 2141 }; 2142 2143 DECLARE_PER_CPU(struct irqtime, cpu_irqtime); 2144 2145 /* 2146 * Returns the irqtime minus the softirq time computed by ksoftirqd. 2147 * Otherwise ksoftirqd's sum_exec_runtime is substracted its own runtime 2148 * and never move forward. 2149 */ 2150 static inline u64 irq_time_read(int cpu) 2151 { 2152 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu); 2153 unsigned int seq; 2154 u64 total; 2155 2156 do { 2157 seq = __u64_stats_fetch_begin(&irqtime->sync); 2158 total = irqtime->total; 2159 } while (__u64_stats_fetch_retry(&irqtime->sync, seq)); 2160 2161 return total; 2162 } 2163 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */ 2164 2165 #ifdef CONFIG_CPU_FREQ 2166 DECLARE_PER_CPU(struct update_util_data *, cpufreq_update_util_data); 2167 2168 /** 2169 * cpufreq_update_util - Take a note about CPU utilization changes. 2170 * @rq: Runqueue to carry out the update for. 2171 * @flags: Update reason flags. 2172 * 2173 * This function is called by the scheduler on the CPU whose utilization is 2174 * being updated. 2175 * 2176 * It can only be called from RCU-sched read-side critical sections. 2177 * 2178 * The way cpufreq is currently arranged requires it to evaluate the CPU 2179 * performance state (frequency/voltage) on a regular basis to prevent it from 2180 * being stuck in a completely inadequate performance level for too long. 2181 * That is not guaranteed to happen if the updates are only triggered from CFS 2182 * and DL, though, because they may not be coming in if only RT tasks are 2183 * active all the time (or there are RT tasks only). 2184 * 2185 * As a workaround for that issue, this function is called periodically by the 2186 * RT sched class to trigger extra cpufreq updates to prevent it from stalling, 2187 * but that really is a band-aid. Going forward it should be replaced with 2188 * solutions targeted more specifically at RT tasks. 2189 */ 2190 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) 2191 { 2192 struct update_util_data *data; 2193 2194 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data, 2195 cpu_of(rq))); 2196 if (data) 2197 data->func(data, rq_clock(rq), flags); 2198 } 2199 #else 2200 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {} 2201 #endif /* CONFIG_CPU_FREQ */ 2202 2203 #ifdef arch_scale_freq_capacity 2204 # ifndef arch_scale_freq_invariant 2205 # define arch_scale_freq_invariant() true 2206 # endif 2207 #else 2208 # define arch_scale_freq_invariant() false 2209 #endif 2210 2211 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL 2212 static inline unsigned long cpu_bw_dl(struct rq *rq) 2213 { 2214 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT; 2215 } 2216 2217 static inline unsigned long cpu_util_dl(struct rq *rq) 2218 { 2219 return READ_ONCE(rq->avg_dl.util_avg); 2220 } 2221 2222 static inline unsigned long cpu_util_cfs(struct rq *rq) 2223 { 2224 unsigned long util = READ_ONCE(rq->cfs.avg.util_avg); 2225 2226 if (sched_feat(UTIL_EST)) { 2227 util = max_t(unsigned long, util, 2228 READ_ONCE(rq->cfs.avg.util_est.enqueued)); 2229 } 2230 2231 return util; 2232 } 2233 2234 static inline unsigned long cpu_util_rt(struct rq *rq) 2235 { 2236 return READ_ONCE(rq->avg_rt.util_avg); 2237 } 2238 #endif 2239 2240 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 2241 static inline unsigned long cpu_util_irq(struct rq *rq) 2242 { 2243 return rq->avg_irq.util_avg; 2244 } 2245 2246 static inline 2247 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 2248 { 2249 util *= (max - irq); 2250 util /= max; 2251 2252 return util; 2253 2254 } 2255 #else 2256 static inline unsigned long cpu_util_irq(struct rq *rq) 2257 { 2258 return 0; 2259 } 2260 2261 static inline 2262 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 2263 { 2264 return util; 2265 } 2266 #endif 2267