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/smt.h> 27 #include <linux/sched/stat.h> 28 #include <linux/sched/sysctl.h> 29 #include <linux/sched/task.h> 30 #include <linux/sched/task_stack.h> 31 #include <linux/sched/topology.h> 32 #include <linux/sched/user.h> 33 #include <linux/sched/wake_q.h> 34 #include <linux/sched/xacct.h> 35 36 #include <uapi/linux/sched/types.h> 37 38 #include <linux/binfmts.h> 39 #include <linux/blkdev.h> 40 #include <linux/compat.h> 41 #include <linux/context_tracking.h> 42 #include <linux/cpufreq.h> 43 #include <linux/cpuidle.h> 44 #include <linux/cpuset.h> 45 #include <linux/ctype.h> 46 #include <linux/debugfs.h> 47 #include <linux/delayacct.h> 48 #include <linux/energy_model.h> 49 #include <linux/init_task.h> 50 #include <linux/kprobes.h> 51 #include <linux/kthread.h> 52 #include <linux/membarrier.h> 53 #include <linux/migrate.h> 54 #include <linux/mmu_context.h> 55 #include <linux/nmi.h> 56 #include <linux/proc_fs.h> 57 #include <linux/prefetch.h> 58 #include <linux/profile.h> 59 #include <linux/psi.h> 60 #include <linux/rcupdate_wait.h> 61 #include <linux/security.h> 62 #include <linux/stop_machine.h> 63 #include <linux/suspend.h> 64 #include <linux/swait.h> 65 #include <linux/syscalls.h> 66 #include <linux/task_work.h> 67 #include <linux/tsacct_kern.h> 68 69 #include <asm/tlb.h> 70 71 #ifdef CONFIG_PARAVIRT 72 # include <asm/paravirt.h> 73 #endif 74 75 #include "cpupri.h" 76 #include "cpudeadline.h" 77 78 #include <trace/events/sched.h> 79 80 #ifdef CONFIG_SCHED_DEBUG 81 # define SCHED_WARN_ON(x) WARN_ONCE(x, #x) 82 #else 83 # define SCHED_WARN_ON(x) ({ (void)(x), 0; }) 84 #endif 85 86 struct rq; 87 struct cpuidle_state; 88 89 /* task_struct::on_rq states: */ 90 #define TASK_ON_RQ_QUEUED 1 91 #define TASK_ON_RQ_MIGRATING 2 92 93 extern __read_mostly int scheduler_running; 94 95 extern unsigned long calc_load_update; 96 extern atomic_long_t calc_load_tasks; 97 98 extern void calc_global_load_tick(struct rq *this_rq); 99 extern long calc_load_fold_active(struct rq *this_rq, long adjust); 100 101 extern void call_trace_sched_update_nr_running(struct rq *rq, int count); 102 /* 103 * Helpers for converting nanosecond timing to jiffy resolution 104 */ 105 #define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ)) 106 107 /* 108 * Increase resolution of nice-level calculations for 64-bit architectures. 109 * The extra resolution improves shares distribution and load balancing of 110 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup 111 * hierarchies, especially on larger systems. This is not a user-visible change 112 * and does not change the user-interface for setting shares/weights. 113 * 114 * We increase resolution only if we have enough bits to allow this increased 115 * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit 116 * are pretty high and the returns do not justify the increased costs. 117 * 118 * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to 119 * increase coverage and consistency always enable it on 64-bit platforms. 120 */ 121 #ifdef CONFIG_64BIT 122 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT) 123 # define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT) 124 # define scale_load_down(w) \ 125 ({ \ 126 unsigned long __w = (w); \ 127 if (__w) \ 128 __w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \ 129 __w; \ 130 }) 131 #else 132 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT) 133 # define scale_load(w) (w) 134 # define scale_load_down(w) (w) 135 #endif 136 137 /* 138 * Task weight (visible to users) and its load (invisible to users) have 139 * independent resolution, but they should be well calibrated. We use 140 * scale_load() and scale_load_down(w) to convert between them. The 141 * following must be true: 142 * 143 * scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD 144 * 145 */ 146 #define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT) 147 148 /* 149 * Single value that decides SCHED_DEADLINE internal math precision. 150 * 10 -> just above 1us 151 * 9 -> just above 0.5us 152 */ 153 #define DL_SCALE 10 154 155 /* 156 * Single value that denotes runtime == period, ie unlimited time. 157 */ 158 #define RUNTIME_INF ((u64)~0ULL) 159 160 static inline int idle_policy(int policy) 161 { 162 return policy == SCHED_IDLE; 163 } 164 static inline int fair_policy(int policy) 165 { 166 return policy == SCHED_NORMAL || policy == SCHED_BATCH; 167 } 168 169 static inline int rt_policy(int policy) 170 { 171 return policy == SCHED_FIFO || policy == SCHED_RR; 172 } 173 174 static inline int dl_policy(int policy) 175 { 176 return policy == SCHED_DEADLINE; 177 } 178 static inline bool valid_policy(int policy) 179 { 180 return idle_policy(policy) || fair_policy(policy) || 181 rt_policy(policy) || dl_policy(policy); 182 } 183 184 static inline int task_has_idle_policy(struct task_struct *p) 185 { 186 return idle_policy(p->policy); 187 } 188 189 static inline int task_has_rt_policy(struct task_struct *p) 190 { 191 return rt_policy(p->policy); 192 } 193 194 static inline int task_has_dl_policy(struct task_struct *p) 195 { 196 return dl_policy(p->policy); 197 } 198 199 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT) 200 201 static inline void update_avg(u64 *avg, u64 sample) 202 { 203 s64 diff = sample - *avg; 204 *avg += diff / 8; 205 } 206 207 /* 208 * !! For sched_setattr_nocheck() (kernel) only !! 209 * 210 * This is actually gross. :( 211 * 212 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE 213 * tasks, but still be able to sleep. We need this on platforms that cannot 214 * atomically change clock frequency. Remove once fast switching will be 215 * available on such platforms. 216 * 217 * SUGOV stands for SchedUtil GOVernor. 218 */ 219 #define SCHED_FLAG_SUGOV 0x10000000 220 221 static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se) 222 { 223 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL 224 return unlikely(dl_se->flags & SCHED_FLAG_SUGOV); 225 #else 226 return false; 227 #endif 228 } 229 230 /* 231 * Tells if entity @a should preempt entity @b. 232 */ 233 static inline bool 234 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b) 235 { 236 return dl_entity_is_special(a) || 237 dl_time_before(a->deadline, b->deadline); 238 } 239 240 /* 241 * This is the priority-queue data structure of the RT scheduling class: 242 */ 243 struct rt_prio_array { 244 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */ 245 struct list_head queue[MAX_RT_PRIO]; 246 }; 247 248 struct rt_bandwidth { 249 /* nests inside the rq lock: */ 250 raw_spinlock_t rt_runtime_lock; 251 ktime_t rt_period; 252 u64 rt_runtime; 253 struct hrtimer rt_period_timer; 254 unsigned int rt_period_active; 255 }; 256 257 void __dl_clear_params(struct task_struct *p); 258 259 struct dl_bandwidth { 260 raw_spinlock_t dl_runtime_lock; 261 u64 dl_runtime; 262 u64 dl_period; 263 }; 264 265 static inline int dl_bandwidth_enabled(void) 266 { 267 return sysctl_sched_rt_runtime >= 0; 268 } 269 270 /* 271 * To keep the bandwidth of -deadline tasks under control 272 * we need some place where: 273 * - store the maximum -deadline bandwidth of each cpu; 274 * - cache the fraction of bandwidth that is currently allocated in 275 * each root domain; 276 * 277 * This is all done in the data structure below. It is similar to the 278 * one used for RT-throttling (rt_bandwidth), with the main difference 279 * that, since here we are only interested in admission control, we 280 * do not decrease any runtime while the group "executes", neither we 281 * need a timer to replenish it. 282 * 283 * With respect to SMP, bandwidth is given on a per root domain basis, 284 * meaning that: 285 * - bw (< 100%) is the deadline bandwidth of each CPU; 286 * - total_bw is the currently allocated bandwidth in each root domain; 287 */ 288 struct dl_bw { 289 raw_spinlock_t lock; 290 u64 bw; 291 u64 total_bw; 292 }; 293 294 static inline void __dl_update(struct dl_bw *dl_b, s64 bw); 295 296 static inline 297 void __dl_sub(struct dl_bw *dl_b, u64 tsk_bw, int cpus) 298 { 299 dl_b->total_bw -= tsk_bw; 300 __dl_update(dl_b, (s32)tsk_bw / cpus); 301 } 302 303 static inline 304 void __dl_add(struct dl_bw *dl_b, u64 tsk_bw, int cpus) 305 { 306 dl_b->total_bw += tsk_bw; 307 __dl_update(dl_b, -((s32)tsk_bw / cpus)); 308 } 309 310 static inline bool __dl_overflow(struct dl_bw *dl_b, unsigned long cap, 311 u64 old_bw, u64 new_bw) 312 { 313 return dl_b->bw != -1 && 314 cap_scale(dl_b->bw, cap) < dl_b->total_bw - old_bw + new_bw; 315 } 316 317 /* 318 * Verify the fitness of task @p to run on @cpu taking into account the 319 * CPU original capacity and the runtime/deadline ratio of the task. 320 * 321 * The function will return true if the CPU original capacity of the 322 * @cpu scaled by SCHED_CAPACITY_SCALE >= runtime/deadline ratio of the 323 * task and false otherwise. 324 */ 325 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu) 326 { 327 unsigned long cap = arch_scale_cpu_capacity(cpu); 328 329 return cap_scale(p->dl.dl_deadline, cap) >= p->dl.dl_runtime; 330 } 331 332 extern void init_dl_bw(struct dl_bw *dl_b); 333 extern int sched_dl_global_validate(void); 334 extern void sched_dl_do_global(void); 335 extern int sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr); 336 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr); 337 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr); 338 extern bool __checkparam_dl(const struct sched_attr *attr); 339 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr); 340 extern int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed); 341 extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 342 extern bool dl_cpu_busy(unsigned int cpu); 343 344 #ifdef CONFIG_CGROUP_SCHED 345 346 #include <linux/cgroup.h> 347 #include <linux/psi.h> 348 349 struct cfs_rq; 350 struct rt_rq; 351 352 extern struct list_head task_groups; 353 354 struct cfs_bandwidth { 355 #ifdef CONFIG_CFS_BANDWIDTH 356 raw_spinlock_t lock; 357 ktime_t period; 358 u64 quota; 359 u64 runtime; 360 s64 hierarchical_quota; 361 362 u8 idle; 363 u8 period_active; 364 u8 slack_started; 365 struct hrtimer period_timer; 366 struct hrtimer slack_timer; 367 struct list_head throttled_cfs_rq; 368 369 /* Statistics: */ 370 int nr_periods; 371 int nr_throttled; 372 u64 throttled_time; 373 #endif 374 }; 375 376 /* Task group related information */ 377 struct task_group { 378 struct cgroup_subsys_state css; 379 380 #ifdef CONFIG_FAIR_GROUP_SCHED 381 /* schedulable entities of this group on each CPU */ 382 struct sched_entity **se; 383 /* runqueue "owned" by this group on each CPU */ 384 struct cfs_rq **cfs_rq; 385 unsigned long shares; 386 387 #ifdef CONFIG_SMP 388 /* 389 * load_avg can be heavily contended at clock tick time, so put 390 * it in its own cacheline separated from the fields above which 391 * will also be accessed at each tick. 392 */ 393 atomic_long_t load_avg ____cacheline_aligned; 394 #endif 395 #endif 396 397 #ifdef CONFIG_RT_GROUP_SCHED 398 struct sched_rt_entity **rt_se; 399 struct rt_rq **rt_rq; 400 401 struct rt_bandwidth rt_bandwidth; 402 #endif 403 404 struct rcu_head rcu; 405 struct list_head list; 406 407 struct task_group *parent; 408 struct list_head siblings; 409 struct list_head children; 410 411 #ifdef CONFIG_SCHED_AUTOGROUP 412 struct autogroup *autogroup; 413 #endif 414 415 struct cfs_bandwidth cfs_bandwidth; 416 417 #ifdef CONFIG_UCLAMP_TASK_GROUP 418 /* The two decimal precision [%] value requested from user-space */ 419 unsigned int uclamp_pct[UCLAMP_CNT]; 420 /* Clamp values requested for a task group */ 421 struct uclamp_se uclamp_req[UCLAMP_CNT]; 422 /* Effective clamp values used for a task group */ 423 struct uclamp_se uclamp[UCLAMP_CNT]; 424 #endif 425 426 }; 427 428 #ifdef CONFIG_FAIR_GROUP_SCHED 429 #define ROOT_TASK_GROUP_LOAD NICE_0_LOAD 430 431 /* 432 * A weight of 0 or 1 can cause arithmetics problems. 433 * A weight of a cfs_rq is the sum of weights of which entities 434 * are queued on this cfs_rq, so a weight of a entity should not be 435 * too large, so as the shares value of a task group. 436 * (The default weight is 1024 - so there's no practical 437 * limitation from this.) 438 */ 439 #define MIN_SHARES (1UL << 1) 440 #define MAX_SHARES (1UL << 18) 441 #endif 442 443 typedef int (*tg_visitor)(struct task_group *, void *); 444 445 extern int walk_tg_tree_from(struct task_group *from, 446 tg_visitor down, tg_visitor up, void *data); 447 448 /* 449 * Iterate the full tree, calling @down when first entering a node and @up when 450 * leaving it for the final time. 451 * 452 * Caller must hold rcu_lock or sufficient equivalent. 453 */ 454 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data) 455 { 456 return walk_tg_tree_from(&root_task_group, down, up, data); 457 } 458 459 extern int tg_nop(struct task_group *tg, void *data); 460 461 extern void free_fair_sched_group(struct task_group *tg); 462 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent); 463 extern void online_fair_sched_group(struct task_group *tg); 464 extern void unregister_fair_sched_group(struct task_group *tg); 465 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, 466 struct sched_entity *se, int cpu, 467 struct sched_entity *parent); 468 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b); 469 470 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b); 471 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b); 472 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq); 473 474 extern void free_rt_sched_group(struct task_group *tg); 475 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent); 476 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, 477 struct sched_rt_entity *rt_se, int cpu, 478 struct sched_rt_entity *parent); 479 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us); 480 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us); 481 extern long sched_group_rt_runtime(struct task_group *tg); 482 extern long sched_group_rt_period(struct task_group *tg); 483 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk); 484 485 extern struct task_group *sched_create_group(struct task_group *parent); 486 extern void sched_online_group(struct task_group *tg, 487 struct task_group *parent); 488 extern void sched_destroy_group(struct task_group *tg); 489 extern void sched_offline_group(struct task_group *tg); 490 491 extern void sched_move_task(struct task_struct *tsk); 492 493 #ifdef CONFIG_FAIR_GROUP_SCHED 494 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); 495 496 #ifdef CONFIG_SMP 497 extern void set_task_rq_fair(struct sched_entity *se, 498 struct cfs_rq *prev, struct cfs_rq *next); 499 #else /* !CONFIG_SMP */ 500 static inline void set_task_rq_fair(struct sched_entity *se, 501 struct cfs_rq *prev, struct cfs_rq *next) { } 502 #endif /* CONFIG_SMP */ 503 #endif /* CONFIG_FAIR_GROUP_SCHED */ 504 505 #else /* CONFIG_CGROUP_SCHED */ 506 507 struct cfs_bandwidth { }; 508 509 #endif /* CONFIG_CGROUP_SCHED */ 510 511 /* CFS-related fields in a runqueue */ 512 struct cfs_rq { 513 struct load_weight load; 514 unsigned int nr_running; 515 unsigned int h_nr_running; /* SCHED_{NORMAL,BATCH,IDLE} */ 516 unsigned int idle_h_nr_running; /* SCHED_IDLE */ 517 518 u64 exec_clock; 519 u64 min_vruntime; 520 #ifndef CONFIG_64BIT 521 u64 min_vruntime_copy; 522 #endif 523 524 struct rb_root_cached tasks_timeline; 525 526 /* 527 * 'curr' points to currently running entity on this cfs_rq. 528 * It is set to NULL otherwise (i.e when none are currently running). 529 */ 530 struct sched_entity *curr; 531 struct sched_entity *next; 532 struct sched_entity *last; 533 struct sched_entity *skip; 534 535 #ifdef CONFIG_SCHED_DEBUG 536 unsigned int nr_spread_over; 537 #endif 538 539 #ifdef CONFIG_SMP 540 /* 541 * CFS load tracking 542 */ 543 struct sched_avg avg; 544 #ifndef CONFIG_64BIT 545 u64 load_last_update_time_copy; 546 #endif 547 struct { 548 raw_spinlock_t lock ____cacheline_aligned; 549 int nr; 550 unsigned long load_avg; 551 unsigned long util_avg; 552 unsigned long runnable_avg; 553 } removed; 554 555 #ifdef CONFIG_FAIR_GROUP_SCHED 556 unsigned long tg_load_avg_contrib; 557 long propagate; 558 long prop_runnable_sum; 559 560 /* 561 * h_load = weight * f(tg) 562 * 563 * Where f(tg) is the recursive weight fraction assigned to 564 * this group. 565 */ 566 unsigned long h_load; 567 u64 last_h_load_update; 568 struct sched_entity *h_load_next; 569 #endif /* CONFIG_FAIR_GROUP_SCHED */ 570 #endif /* CONFIG_SMP */ 571 572 #ifdef CONFIG_FAIR_GROUP_SCHED 573 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */ 574 575 /* 576 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in 577 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities 578 * (like users, containers etc.) 579 * 580 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU. 581 * This list is used during load balance. 582 */ 583 int on_list; 584 struct list_head leaf_cfs_rq_list; 585 struct task_group *tg; /* group that "owns" this runqueue */ 586 587 #ifdef CONFIG_CFS_BANDWIDTH 588 int runtime_enabled; 589 s64 runtime_remaining; 590 591 u64 throttled_clock; 592 u64 throttled_clock_task; 593 u64 throttled_clock_task_time; 594 int throttled; 595 int throttle_count; 596 struct list_head throttled_list; 597 #endif /* CONFIG_CFS_BANDWIDTH */ 598 #endif /* CONFIG_FAIR_GROUP_SCHED */ 599 }; 600 601 static inline int rt_bandwidth_enabled(void) 602 { 603 return sysctl_sched_rt_runtime >= 0; 604 } 605 606 /* RT IPI pull logic requires IRQ_WORK */ 607 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP) 608 # define HAVE_RT_PUSH_IPI 609 #endif 610 611 /* Real-Time classes' related field in a runqueue: */ 612 struct rt_rq { 613 struct rt_prio_array active; 614 unsigned int rt_nr_running; 615 unsigned int rr_nr_running; 616 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED 617 struct { 618 int curr; /* highest queued rt task prio */ 619 #ifdef CONFIG_SMP 620 int next; /* next highest */ 621 #endif 622 } highest_prio; 623 #endif 624 #ifdef CONFIG_SMP 625 unsigned long rt_nr_migratory; 626 unsigned long rt_nr_total; 627 int overloaded; 628 struct plist_head pushable_tasks; 629 630 #endif /* CONFIG_SMP */ 631 int rt_queued; 632 633 int rt_throttled; 634 u64 rt_time; 635 u64 rt_runtime; 636 /* Nests inside the rq lock: */ 637 raw_spinlock_t rt_runtime_lock; 638 639 #ifdef CONFIG_RT_GROUP_SCHED 640 unsigned long rt_nr_boosted; 641 642 struct rq *rq; 643 struct task_group *tg; 644 #endif 645 }; 646 647 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq) 648 { 649 return rt_rq->rt_queued && rt_rq->rt_nr_running; 650 } 651 652 /* Deadline class' related fields in a runqueue */ 653 struct dl_rq { 654 /* runqueue is an rbtree, ordered by deadline */ 655 struct rb_root_cached root; 656 657 unsigned long dl_nr_running; 658 659 #ifdef CONFIG_SMP 660 /* 661 * Deadline values of the currently executing and the 662 * earliest ready task on this rq. Caching these facilitates 663 * the decision whether or not a ready but not running task 664 * should migrate somewhere else. 665 */ 666 struct { 667 u64 curr; 668 u64 next; 669 } earliest_dl; 670 671 unsigned long dl_nr_migratory; 672 int overloaded; 673 674 /* 675 * Tasks on this rq that can be pushed away. They are kept in 676 * an rb-tree, ordered by tasks' deadlines, with caching 677 * of the leftmost (earliest deadline) element. 678 */ 679 struct rb_root_cached pushable_dl_tasks_root; 680 #else 681 struct dl_bw dl_bw; 682 #endif 683 /* 684 * "Active utilization" for this runqueue: increased when a 685 * task wakes up (becomes TASK_RUNNING) and decreased when a 686 * task blocks 687 */ 688 u64 running_bw; 689 690 /* 691 * Utilization of the tasks "assigned" to this runqueue (including 692 * the tasks that are in runqueue and the tasks that executed on this 693 * CPU and blocked). Increased when a task moves to this runqueue, and 694 * decreased when the task moves away (migrates, changes scheduling 695 * policy, or terminates). 696 * This is needed to compute the "inactive utilization" for the 697 * runqueue (inactive utilization = this_bw - running_bw). 698 */ 699 u64 this_bw; 700 u64 extra_bw; 701 702 /* 703 * Inverse of the fraction of CPU utilization that can be reclaimed 704 * by the GRUB algorithm. 705 */ 706 u64 bw_ratio; 707 }; 708 709 #ifdef CONFIG_FAIR_GROUP_SCHED 710 /* An entity is a task if it doesn't "own" a runqueue */ 711 #define entity_is_task(se) (!se->my_q) 712 713 static inline void se_update_runnable(struct sched_entity *se) 714 { 715 if (!entity_is_task(se)) 716 se->runnable_weight = se->my_q->h_nr_running; 717 } 718 719 static inline long se_runnable(struct sched_entity *se) 720 { 721 if (entity_is_task(se)) 722 return !!se->on_rq; 723 else 724 return se->runnable_weight; 725 } 726 727 #else 728 #define entity_is_task(se) 1 729 730 static inline void se_update_runnable(struct sched_entity *se) {} 731 732 static inline long se_runnable(struct sched_entity *se) 733 { 734 return !!se->on_rq; 735 } 736 #endif 737 738 #ifdef CONFIG_SMP 739 /* 740 * XXX we want to get rid of these helpers and use the full load resolution. 741 */ 742 static inline long se_weight(struct sched_entity *se) 743 { 744 return scale_load_down(se->load.weight); 745 } 746 747 748 static inline bool sched_asym_prefer(int a, int b) 749 { 750 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b); 751 } 752 753 struct perf_domain { 754 struct em_perf_domain *em_pd; 755 struct perf_domain *next; 756 struct rcu_head rcu; 757 }; 758 759 /* Scheduling group status flags */ 760 #define SG_OVERLOAD 0x1 /* More than one runnable task on a CPU. */ 761 #define SG_OVERUTILIZED 0x2 /* One or more CPUs are over-utilized. */ 762 763 /* 764 * We add the notion of a root-domain which will be used to define per-domain 765 * variables. Each exclusive cpuset essentially defines an island domain by 766 * fully partitioning the member CPUs from any other cpuset. Whenever a new 767 * exclusive cpuset is created, we also create and attach a new root-domain 768 * object. 769 * 770 */ 771 struct root_domain { 772 atomic_t refcount; 773 atomic_t rto_count; 774 struct rcu_head rcu; 775 cpumask_var_t span; 776 cpumask_var_t online; 777 778 /* 779 * Indicate pullable load on at least one CPU, e.g: 780 * - More than one runnable task 781 * - Running task is misfit 782 */ 783 int overload; 784 785 /* Indicate one or more cpus over-utilized (tipping point) */ 786 int overutilized; 787 788 /* 789 * The bit corresponding to a CPU gets set here if such CPU has more 790 * than one runnable -deadline task (as it is below for RT tasks). 791 */ 792 cpumask_var_t dlo_mask; 793 atomic_t dlo_count; 794 struct dl_bw dl_bw; 795 struct cpudl cpudl; 796 797 /* 798 * Indicate whether a root_domain's dl_bw has been checked or 799 * updated. It's monotonously increasing value. 800 * 801 * Also, some corner cases, like 'wrap around' is dangerous, but given 802 * that u64 is 'big enough'. So that shouldn't be a concern. 803 */ 804 u64 visit_gen; 805 806 #ifdef HAVE_RT_PUSH_IPI 807 /* 808 * For IPI pull requests, loop across the rto_mask. 809 */ 810 struct irq_work rto_push_work; 811 raw_spinlock_t rto_lock; 812 /* These are only updated and read within rto_lock */ 813 int rto_loop; 814 int rto_cpu; 815 /* These atomics are updated outside of a lock */ 816 atomic_t rto_loop_next; 817 atomic_t rto_loop_start; 818 #endif 819 /* 820 * The "RT overload" flag: it gets set if a CPU has more than 821 * one runnable RT task. 822 */ 823 cpumask_var_t rto_mask; 824 struct cpupri cpupri; 825 826 unsigned long max_cpu_capacity; 827 828 /* 829 * NULL-terminated list of performance domains intersecting with the 830 * CPUs of the rd. Protected by RCU. 831 */ 832 struct perf_domain __rcu *pd; 833 }; 834 835 extern void init_defrootdomain(void); 836 extern int sched_init_domains(const struct cpumask *cpu_map); 837 extern void rq_attach_root(struct rq *rq, struct root_domain *rd); 838 extern void sched_get_rd(struct root_domain *rd); 839 extern void sched_put_rd(struct root_domain *rd); 840 841 #ifdef HAVE_RT_PUSH_IPI 842 extern void rto_push_irq_work_func(struct irq_work *work); 843 #endif 844 #endif /* CONFIG_SMP */ 845 846 #ifdef CONFIG_UCLAMP_TASK 847 /* 848 * struct uclamp_bucket - Utilization clamp bucket 849 * @value: utilization clamp value for tasks on this clamp bucket 850 * @tasks: number of RUNNABLE tasks on this clamp bucket 851 * 852 * Keep track of how many tasks are RUNNABLE for a given utilization 853 * clamp value. 854 */ 855 struct uclamp_bucket { 856 unsigned long value : bits_per(SCHED_CAPACITY_SCALE); 857 unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE); 858 }; 859 860 /* 861 * struct uclamp_rq - rq's utilization clamp 862 * @value: currently active clamp values for a rq 863 * @bucket: utilization clamp buckets affecting a rq 864 * 865 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values. 866 * A clamp value is affecting a rq when there is at least one task RUNNABLE 867 * (or actually running) with that value. 868 * 869 * There are up to UCLAMP_CNT possible different clamp values, currently there 870 * are only two: minimum utilization and maximum utilization. 871 * 872 * All utilization clamping values are MAX aggregated, since: 873 * - for util_min: we want to run the CPU at least at the max of the minimum 874 * utilization required by its currently RUNNABLE tasks. 875 * - for util_max: we want to allow the CPU to run up to the max of the 876 * maximum utilization allowed by its currently RUNNABLE tasks. 877 * 878 * Since on each system we expect only a limited number of different 879 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track 880 * the metrics required to compute all the per-rq utilization clamp values. 881 */ 882 struct uclamp_rq { 883 unsigned int value; 884 struct uclamp_bucket bucket[UCLAMP_BUCKETS]; 885 }; 886 887 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used); 888 #endif /* CONFIG_UCLAMP_TASK */ 889 890 /* 891 * This is the main, per-CPU runqueue data structure. 892 * 893 * Locking rule: those places that want to lock multiple runqueues 894 * (such as the load balancing or the thread migration code), lock 895 * acquire operations must be ordered by ascending &runqueue. 896 */ 897 struct rq { 898 /* runqueue lock: */ 899 raw_spinlock_t lock; 900 901 /* 902 * nr_running and cpu_load should be in the same cacheline because 903 * remote CPUs use both these fields when doing load calculation. 904 */ 905 unsigned int nr_running; 906 #ifdef CONFIG_NUMA_BALANCING 907 unsigned int nr_numa_running; 908 unsigned int nr_preferred_running; 909 unsigned int numa_migrate_on; 910 #endif 911 #ifdef CONFIG_NO_HZ_COMMON 912 #ifdef CONFIG_SMP 913 unsigned long last_blocked_load_update_tick; 914 unsigned int has_blocked_load; 915 call_single_data_t nohz_csd; 916 #endif /* CONFIG_SMP */ 917 unsigned int nohz_tick_stopped; 918 atomic_t nohz_flags; 919 #endif /* CONFIG_NO_HZ_COMMON */ 920 921 #ifdef CONFIG_SMP 922 unsigned int ttwu_pending; 923 #endif 924 u64 nr_switches; 925 926 #ifdef CONFIG_UCLAMP_TASK 927 /* Utilization clamp values based on CPU's RUNNABLE tasks */ 928 struct uclamp_rq uclamp[UCLAMP_CNT] ____cacheline_aligned; 929 unsigned int uclamp_flags; 930 #define UCLAMP_FLAG_IDLE 0x01 931 #endif 932 933 struct cfs_rq cfs; 934 struct rt_rq rt; 935 struct dl_rq dl; 936 937 #ifdef CONFIG_FAIR_GROUP_SCHED 938 /* list of leaf cfs_rq on this CPU: */ 939 struct list_head leaf_cfs_rq_list; 940 struct list_head *tmp_alone_branch; 941 #endif /* CONFIG_FAIR_GROUP_SCHED */ 942 943 /* 944 * This is part of a global counter where only the total sum 945 * over all CPUs matters. A task can increase this counter on 946 * one CPU and if it got migrated afterwards it may decrease 947 * it on another CPU. Always updated under the runqueue lock: 948 */ 949 unsigned long nr_uninterruptible; 950 951 struct task_struct __rcu *curr; 952 struct task_struct *idle; 953 struct task_struct *stop; 954 unsigned long next_balance; 955 struct mm_struct *prev_mm; 956 957 unsigned int clock_update_flags; 958 u64 clock; 959 /* Ensure that all clocks are in the same cache line */ 960 u64 clock_task ____cacheline_aligned; 961 u64 clock_pelt; 962 unsigned long lost_idle_time; 963 964 atomic_t nr_iowait; 965 966 #ifdef CONFIG_MEMBARRIER 967 int membarrier_state; 968 #endif 969 970 #ifdef CONFIG_SMP 971 struct root_domain *rd; 972 struct sched_domain __rcu *sd; 973 974 unsigned long cpu_capacity; 975 unsigned long cpu_capacity_orig; 976 977 struct callback_head *balance_callback; 978 979 unsigned char nohz_idle_balance; 980 unsigned char idle_balance; 981 982 unsigned long misfit_task_load; 983 984 /* For active balancing */ 985 int active_balance; 986 int push_cpu; 987 struct cpu_stop_work active_balance_work; 988 989 /* CPU of this runqueue: */ 990 int cpu; 991 int online; 992 993 struct list_head cfs_tasks; 994 995 struct sched_avg avg_rt; 996 struct sched_avg avg_dl; 997 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 998 struct sched_avg avg_irq; 999 #endif 1000 #ifdef CONFIG_SCHED_THERMAL_PRESSURE 1001 struct sched_avg avg_thermal; 1002 #endif 1003 u64 idle_stamp; 1004 u64 avg_idle; 1005 1006 /* This is used to determine avg_idle's max value */ 1007 u64 max_idle_balance_cost; 1008 1009 #ifdef CONFIG_HOTPLUG_CPU 1010 struct rcuwait hotplug_wait; 1011 #endif 1012 #endif /* CONFIG_SMP */ 1013 1014 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 1015 u64 prev_irq_time; 1016 #endif 1017 #ifdef CONFIG_PARAVIRT 1018 u64 prev_steal_time; 1019 #endif 1020 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING 1021 u64 prev_steal_time_rq; 1022 #endif 1023 1024 /* calc_load related fields */ 1025 unsigned long calc_load_update; 1026 long calc_load_active; 1027 1028 #ifdef CONFIG_SCHED_HRTICK 1029 #ifdef CONFIG_SMP 1030 call_single_data_t hrtick_csd; 1031 #endif 1032 struct hrtimer hrtick_timer; 1033 #endif 1034 1035 #ifdef CONFIG_SCHEDSTATS 1036 /* latency stats */ 1037 struct sched_info rq_sched_info; 1038 unsigned long long rq_cpu_time; 1039 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */ 1040 1041 /* sys_sched_yield() stats */ 1042 unsigned int yld_count; 1043 1044 /* schedule() stats */ 1045 unsigned int sched_count; 1046 unsigned int sched_goidle; 1047 1048 /* try_to_wake_up() stats */ 1049 unsigned int ttwu_count; 1050 unsigned int ttwu_local; 1051 #endif 1052 1053 #ifdef CONFIG_CPU_IDLE 1054 /* Must be inspected within a rcu lock section */ 1055 struct cpuidle_state *idle_state; 1056 #endif 1057 1058 #ifdef CONFIG_SMP 1059 unsigned int nr_pinned; 1060 #endif 1061 unsigned int push_busy; 1062 struct cpu_stop_work push_work; 1063 }; 1064 1065 #ifdef CONFIG_FAIR_GROUP_SCHED 1066 1067 /* CPU runqueue to which this cfs_rq is attached */ 1068 static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1069 { 1070 return cfs_rq->rq; 1071 } 1072 1073 #else 1074 1075 static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1076 { 1077 return container_of(cfs_rq, struct rq, cfs); 1078 } 1079 #endif 1080 1081 static inline int cpu_of(struct rq *rq) 1082 { 1083 #ifdef CONFIG_SMP 1084 return rq->cpu; 1085 #else 1086 return 0; 1087 #endif 1088 } 1089 1090 #define MDF_PUSH 0x01 1091 1092 static inline bool is_migration_disabled(struct task_struct *p) 1093 { 1094 #ifdef CONFIG_SMP 1095 return p->migration_disabled; 1096 #else 1097 return false; 1098 #endif 1099 } 1100 1101 #ifdef CONFIG_SCHED_SMT 1102 extern void __update_idle_core(struct rq *rq); 1103 1104 static inline void update_idle_core(struct rq *rq) 1105 { 1106 if (static_branch_unlikely(&sched_smt_present)) 1107 __update_idle_core(rq); 1108 } 1109 1110 #else 1111 static inline void update_idle_core(struct rq *rq) { } 1112 #endif 1113 1114 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); 1115 1116 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) 1117 #define this_rq() this_cpu_ptr(&runqueues) 1118 #define task_rq(p) cpu_rq(task_cpu(p)) 1119 #define cpu_curr(cpu) (cpu_rq(cpu)->curr) 1120 #define raw_rq() raw_cpu_ptr(&runqueues) 1121 1122 extern void update_rq_clock(struct rq *rq); 1123 1124 static inline u64 __rq_clock_broken(struct rq *rq) 1125 { 1126 return READ_ONCE(rq->clock); 1127 } 1128 1129 /* 1130 * rq::clock_update_flags bits 1131 * 1132 * %RQCF_REQ_SKIP - will request skipping of clock update on the next 1133 * call to __schedule(). This is an optimisation to avoid 1134 * neighbouring rq clock updates. 1135 * 1136 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is 1137 * in effect and calls to update_rq_clock() are being ignored. 1138 * 1139 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been 1140 * made to update_rq_clock() since the last time rq::lock was pinned. 1141 * 1142 * If inside of __schedule(), clock_update_flags will have been 1143 * shifted left (a left shift is a cheap operation for the fast path 1144 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use, 1145 * 1146 * if (rq-clock_update_flags >= RQCF_UPDATED) 1147 * 1148 * to check if %RQCF_UPADTED is set. It'll never be shifted more than 1149 * one position though, because the next rq_unpin_lock() will shift it 1150 * back. 1151 */ 1152 #define RQCF_REQ_SKIP 0x01 1153 #define RQCF_ACT_SKIP 0x02 1154 #define RQCF_UPDATED 0x04 1155 1156 static inline void assert_clock_updated(struct rq *rq) 1157 { 1158 /* 1159 * The only reason for not seeing a clock update since the 1160 * last rq_pin_lock() is if we're currently skipping updates. 1161 */ 1162 SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP); 1163 } 1164 1165 static inline u64 rq_clock(struct rq *rq) 1166 { 1167 lockdep_assert_held(&rq->lock); 1168 assert_clock_updated(rq); 1169 1170 return rq->clock; 1171 } 1172 1173 static inline u64 rq_clock_task(struct rq *rq) 1174 { 1175 lockdep_assert_held(&rq->lock); 1176 assert_clock_updated(rq); 1177 1178 return rq->clock_task; 1179 } 1180 1181 /** 1182 * By default the decay is the default pelt decay period. 1183 * The decay shift can change the decay period in 1184 * multiples of 32. 1185 * Decay shift Decay period(ms) 1186 * 0 32 1187 * 1 64 1188 * 2 128 1189 * 3 256 1190 * 4 512 1191 */ 1192 extern int sched_thermal_decay_shift; 1193 1194 static inline u64 rq_clock_thermal(struct rq *rq) 1195 { 1196 return rq_clock_task(rq) >> sched_thermal_decay_shift; 1197 } 1198 1199 static inline void rq_clock_skip_update(struct rq *rq) 1200 { 1201 lockdep_assert_held(&rq->lock); 1202 rq->clock_update_flags |= RQCF_REQ_SKIP; 1203 } 1204 1205 /* 1206 * See rt task throttling, which is the only time a skip 1207 * request is cancelled. 1208 */ 1209 static inline void rq_clock_cancel_skipupdate(struct rq *rq) 1210 { 1211 lockdep_assert_held(&rq->lock); 1212 rq->clock_update_flags &= ~RQCF_REQ_SKIP; 1213 } 1214 1215 struct rq_flags { 1216 unsigned long flags; 1217 struct pin_cookie cookie; 1218 #ifdef CONFIG_SCHED_DEBUG 1219 /* 1220 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the 1221 * current pin context is stashed here in case it needs to be 1222 * restored in rq_repin_lock(). 1223 */ 1224 unsigned int clock_update_flags; 1225 #endif 1226 }; 1227 1228 extern struct callback_head balance_push_callback; 1229 1230 /* 1231 * Lockdep annotation that avoids accidental unlocks; it's like a 1232 * sticky/continuous lockdep_assert_held(). 1233 * 1234 * This avoids code that has access to 'struct rq *rq' (basically everything in 1235 * the scheduler) from accidentally unlocking the rq if they do not also have a 1236 * copy of the (on-stack) 'struct rq_flags rf'. 1237 * 1238 * Also see Documentation/locking/lockdep-design.rst. 1239 */ 1240 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf) 1241 { 1242 rf->cookie = lockdep_pin_lock(&rq->lock); 1243 1244 #ifdef CONFIG_SCHED_DEBUG 1245 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 1246 rf->clock_update_flags = 0; 1247 #ifdef CONFIG_SMP 1248 SCHED_WARN_ON(rq->balance_callback && rq->balance_callback != &balance_push_callback); 1249 #endif 1250 #endif 1251 } 1252 1253 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf) 1254 { 1255 #ifdef CONFIG_SCHED_DEBUG 1256 if (rq->clock_update_flags > RQCF_ACT_SKIP) 1257 rf->clock_update_flags = RQCF_UPDATED; 1258 #endif 1259 1260 lockdep_unpin_lock(&rq->lock, rf->cookie); 1261 } 1262 1263 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf) 1264 { 1265 lockdep_repin_lock(&rq->lock, rf->cookie); 1266 1267 #ifdef CONFIG_SCHED_DEBUG 1268 /* 1269 * Restore the value we stashed in @rf for this pin context. 1270 */ 1271 rq->clock_update_flags |= rf->clock_update_flags; 1272 #endif 1273 } 1274 1275 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1276 __acquires(rq->lock); 1277 1278 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1279 __acquires(p->pi_lock) 1280 __acquires(rq->lock); 1281 1282 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf) 1283 __releases(rq->lock) 1284 { 1285 rq_unpin_lock(rq, rf); 1286 raw_spin_unlock(&rq->lock); 1287 } 1288 1289 static inline void 1290 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) 1291 __releases(rq->lock) 1292 __releases(p->pi_lock) 1293 { 1294 rq_unpin_lock(rq, rf); 1295 raw_spin_unlock(&rq->lock); 1296 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); 1297 } 1298 1299 static inline void 1300 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) 1301 __acquires(rq->lock) 1302 { 1303 raw_spin_lock_irqsave(&rq->lock, rf->flags); 1304 rq_pin_lock(rq, rf); 1305 } 1306 1307 static inline void 1308 rq_lock_irq(struct rq *rq, struct rq_flags *rf) 1309 __acquires(rq->lock) 1310 { 1311 raw_spin_lock_irq(&rq->lock); 1312 rq_pin_lock(rq, rf); 1313 } 1314 1315 static inline void 1316 rq_lock(struct rq *rq, struct rq_flags *rf) 1317 __acquires(rq->lock) 1318 { 1319 raw_spin_lock(&rq->lock); 1320 rq_pin_lock(rq, rf); 1321 } 1322 1323 static inline void 1324 rq_relock(struct rq *rq, struct rq_flags *rf) 1325 __acquires(rq->lock) 1326 { 1327 raw_spin_lock(&rq->lock); 1328 rq_repin_lock(rq, rf); 1329 } 1330 1331 static inline void 1332 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf) 1333 __releases(rq->lock) 1334 { 1335 rq_unpin_lock(rq, rf); 1336 raw_spin_unlock_irqrestore(&rq->lock, rf->flags); 1337 } 1338 1339 static inline void 1340 rq_unlock_irq(struct rq *rq, struct rq_flags *rf) 1341 __releases(rq->lock) 1342 { 1343 rq_unpin_lock(rq, rf); 1344 raw_spin_unlock_irq(&rq->lock); 1345 } 1346 1347 static inline void 1348 rq_unlock(struct rq *rq, struct rq_flags *rf) 1349 __releases(rq->lock) 1350 { 1351 rq_unpin_lock(rq, rf); 1352 raw_spin_unlock(&rq->lock); 1353 } 1354 1355 static inline struct rq * 1356 this_rq_lock_irq(struct rq_flags *rf) 1357 __acquires(rq->lock) 1358 { 1359 struct rq *rq; 1360 1361 local_irq_disable(); 1362 rq = this_rq(); 1363 rq_lock(rq, rf); 1364 return rq; 1365 } 1366 1367 #ifdef CONFIG_NUMA 1368 enum numa_topology_type { 1369 NUMA_DIRECT, 1370 NUMA_GLUELESS_MESH, 1371 NUMA_BACKPLANE, 1372 }; 1373 extern enum numa_topology_type sched_numa_topology_type; 1374 extern int sched_max_numa_distance; 1375 extern bool find_numa_distance(int distance); 1376 extern void sched_init_numa(void); 1377 extern void sched_domains_numa_masks_set(unsigned int cpu); 1378 extern void sched_domains_numa_masks_clear(unsigned int cpu); 1379 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu); 1380 #else 1381 static inline void sched_init_numa(void) { } 1382 static inline void sched_domains_numa_masks_set(unsigned int cpu) { } 1383 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { } 1384 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu) 1385 { 1386 return nr_cpu_ids; 1387 } 1388 #endif 1389 1390 #ifdef CONFIG_NUMA_BALANCING 1391 /* The regions in numa_faults array from task_struct */ 1392 enum numa_faults_stats { 1393 NUMA_MEM = 0, 1394 NUMA_CPU, 1395 NUMA_MEMBUF, 1396 NUMA_CPUBUF 1397 }; 1398 extern void sched_setnuma(struct task_struct *p, int node); 1399 extern int migrate_task_to(struct task_struct *p, int cpu); 1400 extern int migrate_swap(struct task_struct *p, struct task_struct *t, 1401 int cpu, int scpu); 1402 extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p); 1403 #else 1404 static inline void 1405 init_numa_balancing(unsigned long clone_flags, struct task_struct *p) 1406 { 1407 } 1408 #endif /* CONFIG_NUMA_BALANCING */ 1409 1410 #ifdef CONFIG_SMP 1411 1412 static inline void 1413 queue_balance_callback(struct rq *rq, 1414 struct callback_head *head, 1415 void (*func)(struct rq *rq)) 1416 { 1417 lockdep_assert_held(&rq->lock); 1418 1419 if (unlikely(head->next || rq->balance_callback == &balance_push_callback)) 1420 return; 1421 1422 head->func = (void (*)(struct callback_head *))func; 1423 head->next = rq->balance_callback; 1424 rq->balance_callback = head; 1425 } 1426 1427 #define rcu_dereference_check_sched_domain(p) \ 1428 rcu_dereference_check((p), \ 1429 lockdep_is_held(&sched_domains_mutex)) 1430 1431 /* 1432 * The domain tree (rq->sd) is protected by RCU's quiescent state transition. 1433 * See destroy_sched_domains: call_rcu for details. 1434 * 1435 * The domain tree of any CPU may only be accessed from within 1436 * preempt-disabled sections. 1437 */ 1438 #define for_each_domain(cpu, __sd) \ 1439 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \ 1440 __sd; __sd = __sd->parent) 1441 1442 /** 1443 * highest_flag_domain - Return highest sched_domain containing flag. 1444 * @cpu: The CPU whose highest level of sched domain is to 1445 * be returned. 1446 * @flag: The flag to check for the highest sched_domain 1447 * for the given CPU. 1448 * 1449 * Returns the highest sched_domain of a CPU which contains the given flag. 1450 */ 1451 static inline struct sched_domain *highest_flag_domain(int cpu, int flag) 1452 { 1453 struct sched_domain *sd, *hsd = NULL; 1454 1455 for_each_domain(cpu, sd) { 1456 if (!(sd->flags & flag)) 1457 break; 1458 hsd = sd; 1459 } 1460 1461 return hsd; 1462 } 1463 1464 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) 1465 { 1466 struct sched_domain *sd; 1467 1468 for_each_domain(cpu, sd) { 1469 if (sd->flags & flag) 1470 break; 1471 } 1472 1473 return sd; 1474 } 1475 1476 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc); 1477 DECLARE_PER_CPU(int, sd_llc_size); 1478 DECLARE_PER_CPU(int, sd_llc_id); 1479 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared); 1480 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa); 1481 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing); 1482 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity); 1483 extern struct static_key_false sched_asym_cpucapacity; 1484 1485 struct sched_group_capacity { 1486 atomic_t ref; 1487 /* 1488 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity 1489 * for a single CPU. 1490 */ 1491 unsigned long capacity; 1492 unsigned long min_capacity; /* Min per-CPU capacity in group */ 1493 unsigned long max_capacity; /* Max per-CPU capacity in group */ 1494 unsigned long next_update; 1495 int imbalance; /* XXX unrelated to capacity but shared group state */ 1496 1497 #ifdef CONFIG_SCHED_DEBUG 1498 int id; 1499 #endif 1500 1501 unsigned long cpumask[]; /* Balance mask */ 1502 }; 1503 1504 struct sched_group { 1505 struct sched_group *next; /* Must be a circular list */ 1506 atomic_t ref; 1507 1508 unsigned int group_weight; 1509 struct sched_group_capacity *sgc; 1510 int asym_prefer_cpu; /* CPU of highest priority in group */ 1511 1512 /* 1513 * The CPUs this group covers. 1514 * 1515 * NOTE: this field is variable length. (Allocated dynamically 1516 * by attaching extra space to the end of the structure, 1517 * depending on how many CPUs the kernel has booted up with) 1518 */ 1519 unsigned long cpumask[]; 1520 }; 1521 1522 static inline struct cpumask *sched_group_span(struct sched_group *sg) 1523 { 1524 return to_cpumask(sg->cpumask); 1525 } 1526 1527 /* 1528 * See build_balance_mask(). 1529 */ 1530 static inline struct cpumask *group_balance_mask(struct sched_group *sg) 1531 { 1532 return to_cpumask(sg->sgc->cpumask); 1533 } 1534 1535 /** 1536 * group_first_cpu - Returns the first CPU in the cpumask of a sched_group. 1537 * @group: The group whose first CPU is to be returned. 1538 */ 1539 static inline unsigned int group_first_cpu(struct sched_group *group) 1540 { 1541 return cpumask_first(sched_group_span(group)); 1542 } 1543 1544 extern int group_balance_cpu(struct sched_group *sg); 1545 1546 #if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL) 1547 void register_sched_domain_sysctl(void); 1548 void dirty_sched_domain_sysctl(int cpu); 1549 void unregister_sched_domain_sysctl(void); 1550 #else 1551 static inline void register_sched_domain_sysctl(void) 1552 { 1553 } 1554 static inline void dirty_sched_domain_sysctl(int cpu) 1555 { 1556 } 1557 static inline void unregister_sched_domain_sysctl(void) 1558 { 1559 } 1560 #endif 1561 1562 extern void flush_smp_call_function_from_idle(void); 1563 1564 #else /* !CONFIG_SMP: */ 1565 static inline void flush_smp_call_function_from_idle(void) { } 1566 #endif 1567 1568 #include "stats.h" 1569 #include "autogroup.h" 1570 1571 #ifdef CONFIG_CGROUP_SCHED 1572 1573 /* 1574 * Return the group to which this tasks belongs. 1575 * 1576 * We cannot use task_css() and friends because the cgroup subsystem 1577 * changes that value before the cgroup_subsys::attach() method is called, 1578 * therefore we cannot pin it and might observe the wrong value. 1579 * 1580 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup 1581 * core changes this before calling sched_move_task(). 1582 * 1583 * Instead we use a 'copy' which is updated from sched_move_task() while 1584 * holding both task_struct::pi_lock and rq::lock. 1585 */ 1586 static inline struct task_group *task_group(struct task_struct *p) 1587 { 1588 return p->sched_task_group; 1589 } 1590 1591 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ 1592 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) 1593 { 1594 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED) 1595 struct task_group *tg = task_group(p); 1596 #endif 1597 1598 #ifdef CONFIG_FAIR_GROUP_SCHED 1599 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]); 1600 p->se.cfs_rq = tg->cfs_rq[cpu]; 1601 p->se.parent = tg->se[cpu]; 1602 #endif 1603 1604 #ifdef CONFIG_RT_GROUP_SCHED 1605 p->rt.rt_rq = tg->rt_rq[cpu]; 1606 p->rt.parent = tg->rt_se[cpu]; 1607 #endif 1608 } 1609 1610 #else /* CONFIG_CGROUP_SCHED */ 1611 1612 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } 1613 static inline struct task_group *task_group(struct task_struct *p) 1614 { 1615 return NULL; 1616 } 1617 1618 #endif /* CONFIG_CGROUP_SCHED */ 1619 1620 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) 1621 { 1622 set_task_rq(p, cpu); 1623 #ifdef CONFIG_SMP 1624 /* 1625 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be 1626 * successfully executed on another CPU. We must ensure that updates of 1627 * per-task data have been completed by this moment. 1628 */ 1629 smp_wmb(); 1630 #ifdef CONFIG_THREAD_INFO_IN_TASK 1631 WRITE_ONCE(p->cpu, cpu); 1632 #else 1633 WRITE_ONCE(task_thread_info(p)->cpu, cpu); 1634 #endif 1635 p->wake_cpu = cpu; 1636 #endif 1637 } 1638 1639 /* 1640 * Tunables that become constants when CONFIG_SCHED_DEBUG is off: 1641 */ 1642 #ifdef CONFIG_SCHED_DEBUG 1643 # include <linux/static_key.h> 1644 # define const_debug __read_mostly 1645 #else 1646 # define const_debug const 1647 #endif 1648 1649 #define SCHED_FEAT(name, enabled) \ 1650 __SCHED_FEAT_##name , 1651 1652 enum { 1653 #include "features.h" 1654 __SCHED_FEAT_NR, 1655 }; 1656 1657 #undef SCHED_FEAT 1658 1659 #ifdef CONFIG_SCHED_DEBUG 1660 1661 /* 1662 * To support run-time toggling of sched features, all the translation units 1663 * (but core.c) reference the sysctl_sched_features defined in core.c. 1664 */ 1665 extern const_debug unsigned int sysctl_sched_features; 1666 1667 #ifdef CONFIG_JUMP_LABEL 1668 #define SCHED_FEAT(name, enabled) \ 1669 static __always_inline bool static_branch_##name(struct static_key *key) \ 1670 { \ 1671 return static_key_##enabled(key); \ 1672 } 1673 1674 #include "features.h" 1675 #undef SCHED_FEAT 1676 1677 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR]; 1678 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x])) 1679 1680 #else /* !CONFIG_JUMP_LABEL */ 1681 1682 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) 1683 1684 #endif /* CONFIG_JUMP_LABEL */ 1685 1686 #else /* !SCHED_DEBUG */ 1687 1688 /* 1689 * Each translation unit has its own copy of sysctl_sched_features to allow 1690 * constants propagation at compile time and compiler optimization based on 1691 * features default. 1692 */ 1693 #define SCHED_FEAT(name, enabled) \ 1694 (1UL << __SCHED_FEAT_##name) * enabled | 1695 static const_debug __maybe_unused unsigned int sysctl_sched_features = 1696 #include "features.h" 1697 0; 1698 #undef SCHED_FEAT 1699 1700 #define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) 1701 1702 #endif /* SCHED_DEBUG */ 1703 1704 extern struct static_key_false sched_numa_balancing; 1705 extern struct static_key_false sched_schedstats; 1706 1707 static inline u64 global_rt_period(void) 1708 { 1709 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC; 1710 } 1711 1712 static inline u64 global_rt_runtime(void) 1713 { 1714 if (sysctl_sched_rt_runtime < 0) 1715 return RUNTIME_INF; 1716 1717 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC; 1718 } 1719 1720 static inline int task_current(struct rq *rq, struct task_struct *p) 1721 { 1722 return rq->curr == p; 1723 } 1724 1725 static inline int task_running(struct rq *rq, struct task_struct *p) 1726 { 1727 #ifdef CONFIG_SMP 1728 return p->on_cpu; 1729 #else 1730 return task_current(rq, p); 1731 #endif 1732 } 1733 1734 static inline int task_on_rq_queued(struct task_struct *p) 1735 { 1736 return p->on_rq == TASK_ON_RQ_QUEUED; 1737 } 1738 1739 static inline int task_on_rq_migrating(struct task_struct *p) 1740 { 1741 return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING; 1742 } 1743 1744 /* Wake flags. The first three directly map to some SD flag value */ 1745 #define WF_EXEC 0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */ 1746 #define WF_FORK 0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */ 1747 #define WF_TTWU 0x08 /* Wakeup; maps to SD_BALANCE_WAKE */ 1748 1749 #define WF_SYNC 0x10 /* Waker goes to sleep after wakeup */ 1750 #define WF_MIGRATED 0x20 /* Internal use, task got migrated */ 1751 #define WF_ON_CPU 0x40 /* Wakee is on_cpu */ 1752 1753 #ifdef CONFIG_SMP 1754 static_assert(WF_EXEC == SD_BALANCE_EXEC); 1755 static_assert(WF_FORK == SD_BALANCE_FORK); 1756 static_assert(WF_TTWU == SD_BALANCE_WAKE); 1757 #endif 1758 1759 /* 1760 * To aid in avoiding the subversion of "niceness" due to uneven distribution 1761 * of tasks with abnormal "nice" values across CPUs the contribution that 1762 * each task makes to its run queue's load is weighted according to its 1763 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a 1764 * scaled version of the new time slice allocation that they receive on time 1765 * slice expiry etc. 1766 */ 1767 1768 #define WEIGHT_IDLEPRIO 3 1769 #define WMULT_IDLEPRIO 1431655765 1770 1771 extern const int sched_prio_to_weight[40]; 1772 extern const u32 sched_prio_to_wmult[40]; 1773 1774 /* 1775 * {de,en}queue flags: 1776 * 1777 * DEQUEUE_SLEEP - task is no longer runnable 1778 * ENQUEUE_WAKEUP - task just became runnable 1779 * 1780 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks 1781 * are in a known state which allows modification. Such pairs 1782 * should preserve as much state as possible. 1783 * 1784 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location 1785 * in the runqueue. 1786 * 1787 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified) 1788 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline) 1789 * ENQUEUE_MIGRATED - the task was migrated during wakeup 1790 * 1791 */ 1792 1793 #define DEQUEUE_SLEEP 0x01 1794 #define DEQUEUE_SAVE 0x02 /* Matches ENQUEUE_RESTORE */ 1795 #define DEQUEUE_MOVE 0x04 /* Matches ENQUEUE_MOVE */ 1796 #define DEQUEUE_NOCLOCK 0x08 /* Matches ENQUEUE_NOCLOCK */ 1797 1798 #define ENQUEUE_WAKEUP 0x01 1799 #define ENQUEUE_RESTORE 0x02 1800 #define ENQUEUE_MOVE 0x04 1801 #define ENQUEUE_NOCLOCK 0x08 1802 1803 #define ENQUEUE_HEAD 0x10 1804 #define ENQUEUE_REPLENISH 0x20 1805 #ifdef CONFIG_SMP 1806 #define ENQUEUE_MIGRATED 0x40 1807 #else 1808 #define ENQUEUE_MIGRATED 0x00 1809 #endif 1810 1811 #define RETRY_TASK ((void *)-1UL) 1812 1813 struct sched_class { 1814 1815 #ifdef CONFIG_UCLAMP_TASK 1816 int uclamp_enabled; 1817 #endif 1818 1819 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags); 1820 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags); 1821 void (*yield_task) (struct rq *rq); 1822 bool (*yield_to_task)(struct rq *rq, struct task_struct *p); 1823 1824 void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags); 1825 1826 struct task_struct *(*pick_next_task)(struct rq *rq); 1827 1828 void (*put_prev_task)(struct rq *rq, struct task_struct *p); 1829 void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first); 1830 1831 #ifdef CONFIG_SMP 1832 int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf); 1833 int (*select_task_rq)(struct task_struct *p, int task_cpu, int flags); 1834 void (*migrate_task_rq)(struct task_struct *p, int new_cpu); 1835 1836 void (*task_woken)(struct rq *this_rq, struct task_struct *task); 1837 1838 void (*set_cpus_allowed)(struct task_struct *p, 1839 const struct cpumask *newmask, 1840 u32 flags); 1841 1842 void (*rq_online)(struct rq *rq); 1843 void (*rq_offline)(struct rq *rq); 1844 1845 struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq); 1846 #endif 1847 1848 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued); 1849 void (*task_fork)(struct task_struct *p); 1850 void (*task_dead)(struct task_struct *p); 1851 1852 /* 1853 * The switched_from() call is allowed to drop rq->lock, therefore we 1854 * cannot assume the switched_from/switched_to pair is serliazed by 1855 * rq->lock. They are however serialized by p->pi_lock. 1856 */ 1857 void (*switched_from)(struct rq *this_rq, struct task_struct *task); 1858 void (*switched_to) (struct rq *this_rq, struct task_struct *task); 1859 void (*prio_changed) (struct rq *this_rq, struct task_struct *task, 1860 int oldprio); 1861 1862 unsigned int (*get_rr_interval)(struct rq *rq, 1863 struct task_struct *task); 1864 1865 void (*update_curr)(struct rq *rq); 1866 1867 #define TASK_SET_GROUP 0 1868 #define TASK_MOVE_GROUP 1 1869 1870 #ifdef CONFIG_FAIR_GROUP_SCHED 1871 void (*task_change_group)(struct task_struct *p, int type); 1872 #endif 1873 }; 1874 1875 static inline void put_prev_task(struct rq *rq, struct task_struct *prev) 1876 { 1877 WARN_ON_ONCE(rq->curr != prev); 1878 prev->sched_class->put_prev_task(rq, prev); 1879 } 1880 1881 static inline void set_next_task(struct rq *rq, struct task_struct *next) 1882 { 1883 WARN_ON_ONCE(rq->curr != next); 1884 next->sched_class->set_next_task(rq, next, false); 1885 } 1886 1887 1888 /* 1889 * Helper to define a sched_class instance; each one is placed in a separate 1890 * section which is ordered by the linker script: 1891 * 1892 * include/asm-generic/vmlinux.lds.h 1893 * 1894 * Also enforce alignment on the instance, not the type, to guarantee layout. 1895 */ 1896 #define DEFINE_SCHED_CLASS(name) \ 1897 const struct sched_class name##_sched_class \ 1898 __aligned(__alignof__(struct sched_class)) \ 1899 __section("__" #name "_sched_class") 1900 1901 /* Defined in include/asm-generic/vmlinux.lds.h */ 1902 extern struct sched_class __begin_sched_classes[]; 1903 extern struct sched_class __end_sched_classes[]; 1904 1905 #define sched_class_highest (__end_sched_classes - 1) 1906 #define sched_class_lowest (__begin_sched_classes - 1) 1907 1908 #define for_class_range(class, _from, _to) \ 1909 for (class = (_from); class != (_to); class--) 1910 1911 #define for_each_class(class) \ 1912 for_class_range(class, sched_class_highest, sched_class_lowest) 1913 1914 extern const struct sched_class stop_sched_class; 1915 extern const struct sched_class dl_sched_class; 1916 extern const struct sched_class rt_sched_class; 1917 extern const struct sched_class fair_sched_class; 1918 extern const struct sched_class idle_sched_class; 1919 1920 static inline bool sched_stop_runnable(struct rq *rq) 1921 { 1922 return rq->stop && task_on_rq_queued(rq->stop); 1923 } 1924 1925 static inline bool sched_dl_runnable(struct rq *rq) 1926 { 1927 return rq->dl.dl_nr_running > 0; 1928 } 1929 1930 static inline bool sched_rt_runnable(struct rq *rq) 1931 { 1932 return rq->rt.rt_queued > 0; 1933 } 1934 1935 static inline bool sched_fair_runnable(struct rq *rq) 1936 { 1937 return rq->cfs.nr_running > 0; 1938 } 1939 1940 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf); 1941 extern struct task_struct *pick_next_task_idle(struct rq *rq); 1942 1943 #define SCA_CHECK 0x01 1944 #define SCA_MIGRATE_DISABLE 0x02 1945 #define SCA_MIGRATE_ENABLE 0x04 1946 1947 #ifdef CONFIG_SMP 1948 1949 extern void update_group_capacity(struct sched_domain *sd, int cpu); 1950 1951 extern void trigger_load_balance(struct rq *rq); 1952 1953 extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask, u32 flags); 1954 1955 static inline struct task_struct *get_push_task(struct rq *rq) 1956 { 1957 struct task_struct *p = rq->curr; 1958 1959 lockdep_assert_held(&rq->lock); 1960 1961 if (rq->push_busy) 1962 return NULL; 1963 1964 if (p->nr_cpus_allowed == 1) 1965 return NULL; 1966 1967 rq->push_busy = true; 1968 return get_task_struct(p); 1969 } 1970 1971 extern int push_cpu_stop(void *arg); 1972 1973 #endif 1974 1975 #ifdef CONFIG_CPU_IDLE 1976 static inline void idle_set_state(struct rq *rq, 1977 struct cpuidle_state *idle_state) 1978 { 1979 rq->idle_state = idle_state; 1980 } 1981 1982 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 1983 { 1984 SCHED_WARN_ON(!rcu_read_lock_held()); 1985 1986 return rq->idle_state; 1987 } 1988 #else 1989 static inline void idle_set_state(struct rq *rq, 1990 struct cpuidle_state *idle_state) 1991 { 1992 } 1993 1994 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 1995 { 1996 return NULL; 1997 } 1998 #endif 1999 2000 extern void schedule_idle(void); 2001 2002 extern void sysrq_sched_debug_show(void); 2003 extern void sched_init_granularity(void); 2004 extern void update_max_interval(void); 2005 2006 extern void init_sched_dl_class(void); 2007 extern void init_sched_rt_class(void); 2008 extern void init_sched_fair_class(void); 2009 2010 extern void reweight_task(struct task_struct *p, int prio); 2011 2012 extern void resched_curr(struct rq *rq); 2013 extern void resched_cpu(int cpu); 2014 2015 extern struct rt_bandwidth def_rt_bandwidth; 2016 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime); 2017 2018 extern struct dl_bandwidth def_dl_bandwidth; 2019 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime); 2020 extern void init_dl_task_timer(struct sched_dl_entity *dl_se); 2021 extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se); 2022 2023 #define BW_SHIFT 20 2024 #define BW_UNIT (1 << BW_SHIFT) 2025 #define RATIO_SHIFT 8 2026 #define MAX_BW_BITS (64 - BW_SHIFT) 2027 #define MAX_BW ((1ULL << MAX_BW_BITS) - 1) 2028 unsigned long to_ratio(u64 period, u64 runtime); 2029 2030 extern void init_entity_runnable_average(struct sched_entity *se); 2031 extern void post_init_entity_util_avg(struct task_struct *p); 2032 2033 #ifdef CONFIG_NO_HZ_FULL 2034 extern bool sched_can_stop_tick(struct rq *rq); 2035 extern int __init sched_tick_offload_init(void); 2036 2037 /* 2038 * Tick may be needed by tasks in the runqueue depending on their policy and 2039 * requirements. If tick is needed, lets send the target an IPI to kick it out of 2040 * nohz mode if necessary. 2041 */ 2042 static inline void sched_update_tick_dependency(struct rq *rq) 2043 { 2044 int cpu = cpu_of(rq); 2045 2046 if (!tick_nohz_full_cpu(cpu)) 2047 return; 2048 2049 if (sched_can_stop_tick(rq)) 2050 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED); 2051 else 2052 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED); 2053 } 2054 #else 2055 static inline int sched_tick_offload_init(void) { return 0; } 2056 static inline void sched_update_tick_dependency(struct rq *rq) { } 2057 #endif 2058 2059 static inline void add_nr_running(struct rq *rq, unsigned count) 2060 { 2061 unsigned prev_nr = rq->nr_running; 2062 2063 rq->nr_running = prev_nr + count; 2064 if (trace_sched_update_nr_running_tp_enabled()) { 2065 call_trace_sched_update_nr_running(rq, count); 2066 } 2067 2068 #ifdef CONFIG_SMP 2069 if (prev_nr < 2 && rq->nr_running >= 2) { 2070 if (!READ_ONCE(rq->rd->overload)) 2071 WRITE_ONCE(rq->rd->overload, 1); 2072 } 2073 #endif 2074 2075 sched_update_tick_dependency(rq); 2076 } 2077 2078 static inline void sub_nr_running(struct rq *rq, unsigned count) 2079 { 2080 rq->nr_running -= count; 2081 if (trace_sched_update_nr_running_tp_enabled()) { 2082 call_trace_sched_update_nr_running(rq, -count); 2083 } 2084 2085 /* Check if we still need preemption */ 2086 sched_update_tick_dependency(rq); 2087 } 2088 2089 extern void activate_task(struct rq *rq, struct task_struct *p, int flags); 2090 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags); 2091 2092 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags); 2093 2094 extern const_debug unsigned int sysctl_sched_nr_migrate; 2095 extern const_debug unsigned int sysctl_sched_migration_cost; 2096 2097 #ifdef CONFIG_SCHED_HRTICK 2098 2099 /* 2100 * Use hrtick when: 2101 * - enabled by features 2102 * - hrtimer is actually high res 2103 */ 2104 static inline int hrtick_enabled(struct rq *rq) 2105 { 2106 if (!sched_feat(HRTICK)) 2107 return 0; 2108 if (!cpu_active(cpu_of(rq))) 2109 return 0; 2110 return hrtimer_is_hres_active(&rq->hrtick_timer); 2111 } 2112 2113 void hrtick_start(struct rq *rq, u64 delay); 2114 2115 #else 2116 2117 static inline int hrtick_enabled(struct rq *rq) 2118 { 2119 return 0; 2120 } 2121 2122 #endif /* CONFIG_SCHED_HRTICK */ 2123 2124 #ifndef arch_scale_freq_tick 2125 static __always_inline 2126 void arch_scale_freq_tick(void) 2127 { 2128 } 2129 #endif 2130 2131 #ifndef arch_scale_freq_capacity 2132 /** 2133 * arch_scale_freq_capacity - get the frequency scale factor of a given CPU. 2134 * @cpu: the CPU in question. 2135 * 2136 * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e. 2137 * 2138 * f_curr 2139 * ------ * SCHED_CAPACITY_SCALE 2140 * f_max 2141 */ 2142 static __always_inline 2143 unsigned long arch_scale_freq_capacity(int cpu) 2144 { 2145 return SCHED_CAPACITY_SCALE; 2146 } 2147 #endif 2148 2149 #ifdef CONFIG_SMP 2150 #ifdef CONFIG_PREEMPTION 2151 2152 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2); 2153 2154 /* 2155 * fair double_lock_balance: Safely acquires both rq->locks in a fair 2156 * way at the expense of forcing extra atomic operations in all 2157 * invocations. This assures that the double_lock is acquired using the 2158 * same underlying policy as the spinlock_t on this architecture, which 2159 * reduces latency compared to the unfair variant below. However, it 2160 * also adds more overhead and therefore may reduce throughput. 2161 */ 2162 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 2163 __releases(this_rq->lock) 2164 __acquires(busiest->lock) 2165 __acquires(this_rq->lock) 2166 { 2167 raw_spin_unlock(&this_rq->lock); 2168 double_rq_lock(this_rq, busiest); 2169 2170 return 1; 2171 } 2172 2173 #else 2174 /* 2175 * Unfair double_lock_balance: Optimizes throughput at the expense of 2176 * latency by eliminating extra atomic operations when the locks are 2177 * already in proper order on entry. This favors lower CPU-ids and will 2178 * grant the double lock to lower CPUs over higher ids under contention, 2179 * regardless of entry order into the function. 2180 */ 2181 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 2182 __releases(this_rq->lock) 2183 __acquires(busiest->lock) 2184 __acquires(this_rq->lock) 2185 { 2186 int ret = 0; 2187 2188 if (unlikely(!raw_spin_trylock(&busiest->lock))) { 2189 if (busiest < this_rq) { 2190 raw_spin_unlock(&this_rq->lock); 2191 raw_spin_lock(&busiest->lock); 2192 raw_spin_lock_nested(&this_rq->lock, 2193 SINGLE_DEPTH_NESTING); 2194 ret = 1; 2195 } else 2196 raw_spin_lock_nested(&busiest->lock, 2197 SINGLE_DEPTH_NESTING); 2198 } 2199 return ret; 2200 } 2201 2202 #endif /* CONFIG_PREEMPTION */ 2203 2204 /* 2205 * double_lock_balance - lock the busiest runqueue, this_rq is locked already. 2206 */ 2207 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest) 2208 { 2209 if (unlikely(!irqs_disabled())) { 2210 /* printk() doesn't work well under rq->lock */ 2211 raw_spin_unlock(&this_rq->lock); 2212 BUG_ON(1); 2213 } 2214 2215 return _double_lock_balance(this_rq, busiest); 2216 } 2217 2218 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest) 2219 __releases(busiest->lock) 2220 { 2221 raw_spin_unlock(&busiest->lock); 2222 lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_); 2223 } 2224 2225 static inline void double_lock(spinlock_t *l1, spinlock_t *l2) 2226 { 2227 if (l1 > l2) 2228 swap(l1, l2); 2229 2230 spin_lock(l1); 2231 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 2232 } 2233 2234 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2) 2235 { 2236 if (l1 > l2) 2237 swap(l1, l2); 2238 2239 spin_lock_irq(l1); 2240 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 2241 } 2242 2243 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2) 2244 { 2245 if (l1 > l2) 2246 swap(l1, l2); 2247 2248 raw_spin_lock(l1); 2249 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 2250 } 2251 2252 /* 2253 * double_rq_lock - safely lock two runqueues 2254 * 2255 * Note this does not disable interrupts like task_rq_lock, 2256 * you need to do so manually before calling. 2257 */ 2258 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2) 2259 __acquires(rq1->lock) 2260 __acquires(rq2->lock) 2261 { 2262 BUG_ON(!irqs_disabled()); 2263 if (rq1 == rq2) { 2264 raw_spin_lock(&rq1->lock); 2265 __acquire(rq2->lock); /* Fake it out ;) */ 2266 } else { 2267 if (rq1 < rq2) { 2268 raw_spin_lock(&rq1->lock); 2269 raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING); 2270 } else { 2271 raw_spin_lock(&rq2->lock); 2272 raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING); 2273 } 2274 } 2275 } 2276 2277 /* 2278 * double_rq_unlock - safely unlock two runqueues 2279 * 2280 * Note this does not restore interrupts like task_rq_unlock, 2281 * you need to do so manually after calling. 2282 */ 2283 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 2284 __releases(rq1->lock) 2285 __releases(rq2->lock) 2286 { 2287 raw_spin_unlock(&rq1->lock); 2288 if (rq1 != rq2) 2289 raw_spin_unlock(&rq2->lock); 2290 else 2291 __release(rq2->lock); 2292 } 2293 2294 extern void set_rq_online (struct rq *rq); 2295 extern void set_rq_offline(struct rq *rq); 2296 extern bool sched_smp_initialized; 2297 2298 #else /* CONFIG_SMP */ 2299 2300 /* 2301 * double_rq_lock - safely lock two runqueues 2302 * 2303 * Note this does not disable interrupts like task_rq_lock, 2304 * you need to do so manually before calling. 2305 */ 2306 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2) 2307 __acquires(rq1->lock) 2308 __acquires(rq2->lock) 2309 { 2310 BUG_ON(!irqs_disabled()); 2311 BUG_ON(rq1 != rq2); 2312 raw_spin_lock(&rq1->lock); 2313 __acquire(rq2->lock); /* Fake it out ;) */ 2314 } 2315 2316 /* 2317 * double_rq_unlock - safely unlock two runqueues 2318 * 2319 * Note this does not restore interrupts like task_rq_unlock, 2320 * you need to do so manually after calling. 2321 */ 2322 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 2323 __releases(rq1->lock) 2324 __releases(rq2->lock) 2325 { 2326 BUG_ON(rq1 != rq2); 2327 raw_spin_unlock(&rq1->lock); 2328 __release(rq2->lock); 2329 } 2330 2331 #endif 2332 2333 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq); 2334 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq); 2335 2336 #ifdef CONFIG_SCHED_DEBUG 2337 extern bool sched_debug_enabled; 2338 2339 extern void print_cfs_stats(struct seq_file *m, int cpu); 2340 extern void print_rt_stats(struct seq_file *m, int cpu); 2341 extern void print_dl_stats(struct seq_file *m, int cpu); 2342 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 2343 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq); 2344 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq); 2345 #ifdef CONFIG_NUMA_BALANCING 2346 extern void 2347 show_numa_stats(struct task_struct *p, struct seq_file *m); 2348 extern void 2349 print_numa_stats(struct seq_file *m, int node, unsigned long tsf, 2350 unsigned long tpf, unsigned long gsf, unsigned long gpf); 2351 #endif /* CONFIG_NUMA_BALANCING */ 2352 #endif /* CONFIG_SCHED_DEBUG */ 2353 2354 extern void init_cfs_rq(struct cfs_rq *cfs_rq); 2355 extern void init_rt_rq(struct rt_rq *rt_rq); 2356 extern void init_dl_rq(struct dl_rq *dl_rq); 2357 2358 extern void cfs_bandwidth_usage_inc(void); 2359 extern void cfs_bandwidth_usage_dec(void); 2360 2361 #ifdef CONFIG_NO_HZ_COMMON 2362 #define NOHZ_BALANCE_KICK_BIT 0 2363 #define NOHZ_STATS_KICK_BIT 1 2364 2365 #define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT) 2366 #define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT) 2367 2368 #define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK) 2369 2370 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags) 2371 2372 extern void nohz_balance_exit_idle(struct rq *rq); 2373 #else 2374 static inline void nohz_balance_exit_idle(struct rq *rq) { } 2375 #endif 2376 2377 2378 #ifdef CONFIG_SMP 2379 static inline 2380 void __dl_update(struct dl_bw *dl_b, s64 bw) 2381 { 2382 struct root_domain *rd = container_of(dl_b, struct root_domain, dl_bw); 2383 int i; 2384 2385 RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(), 2386 "sched RCU must be held"); 2387 for_each_cpu_and(i, rd->span, cpu_active_mask) { 2388 struct rq *rq = cpu_rq(i); 2389 2390 rq->dl.extra_bw += bw; 2391 } 2392 } 2393 #else 2394 static inline 2395 void __dl_update(struct dl_bw *dl_b, s64 bw) 2396 { 2397 struct dl_rq *dl = container_of(dl_b, struct dl_rq, dl_bw); 2398 2399 dl->extra_bw += bw; 2400 } 2401 #endif 2402 2403 2404 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 2405 struct irqtime { 2406 u64 total; 2407 u64 tick_delta; 2408 u64 irq_start_time; 2409 struct u64_stats_sync sync; 2410 }; 2411 2412 DECLARE_PER_CPU(struct irqtime, cpu_irqtime); 2413 2414 /* 2415 * Returns the irqtime minus the softirq time computed by ksoftirqd. 2416 * Otherwise ksoftirqd's sum_exec_runtime is substracted its own runtime 2417 * and never move forward. 2418 */ 2419 static inline u64 irq_time_read(int cpu) 2420 { 2421 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu); 2422 unsigned int seq; 2423 u64 total; 2424 2425 do { 2426 seq = __u64_stats_fetch_begin(&irqtime->sync); 2427 total = irqtime->total; 2428 } while (__u64_stats_fetch_retry(&irqtime->sync, seq)); 2429 2430 return total; 2431 } 2432 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */ 2433 2434 #ifdef CONFIG_CPU_FREQ 2435 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data); 2436 2437 /** 2438 * cpufreq_update_util - Take a note about CPU utilization changes. 2439 * @rq: Runqueue to carry out the update for. 2440 * @flags: Update reason flags. 2441 * 2442 * This function is called by the scheduler on the CPU whose utilization is 2443 * being updated. 2444 * 2445 * It can only be called from RCU-sched read-side critical sections. 2446 * 2447 * The way cpufreq is currently arranged requires it to evaluate the CPU 2448 * performance state (frequency/voltage) on a regular basis to prevent it from 2449 * being stuck in a completely inadequate performance level for too long. 2450 * That is not guaranteed to happen if the updates are only triggered from CFS 2451 * and DL, though, because they may not be coming in if only RT tasks are 2452 * active all the time (or there are RT tasks only). 2453 * 2454 * As a workaround for that issue, this function is called periodically by the 2455 * RT sched class to trigger extra cpufreq updates to prevent it from stalling, 2456 * but that really is a band-aid. Going forward it should be replaced with 2457 * solutions targeted more specifically at RT tasks. 2458 */ 2459 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) 2460 { 2461 struct update_util_data *data; 2462 2463 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data, 2464 cpu_of(rq))); 2465 if (data) 2466 data->func(data, rq_clock(rq), flags); 2467 } 2468 #else 2469 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {} 2470 #endif /* CONFIG_CPU_FREQ */ 2471 2472 #ifdef CONFIG_UCLAMP_TASK 2473 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id); 2474 2475 /** 2476 * uclamp_rq_util_with - clamp @util with @rq and @p effective uclamp values. 2477 * @rq: The rq to clamp against. Must not be NULL. 2478 * @util: The util value to clamp. 2479 * @p: The task to clamp against. Can be NULL if you want to clamp 2480 * against @rq only. 2481 * 2482 * Clamps the passed @util to the max(@rq, @p) effective uclamp values. 2483 * 2484 * If sched_uclamp_used static key is disabled, then just return the util 2485 * without any clamping since uclamp aggregation at the rq level in the fast 2486 * path is disabled, rendering this operation a NOP. 2487 * 2488 * Use uclamp_eff_value() if you don't care about uclamp values at rq level. It 2489 * will return the correct effective uclamp value of the task even if the 2490 * static key is disabled. 2491 */ 2492 static __always_inline 2493 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util, 2494 struct task_struct *p) 2495 { 2496 unsigned long min_util; 2497 unsigned long max_util; 2498 2499 if (!static_branch_likely(&sched_uclamp_used)) 2500 return util; 2501 2502 min_util = READ_ONCE(rq->uclamp[UCLAMP_MIN].value); 2503 max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value); 2504 2505 if (p) { 2506 min_util = max(min_util, uclamp_eff_value(p, UCLAMP_MIN)); 2507 max_util = max(max_util, uclamp_eff_value(p, UCLAMP_MAX)); 2508 } 2509 2510 /* 2511 * Since CPU's {min,max}_util clamps are MAX aggregated considering 2512 * RUNNABLE tasks with _different_ clamps, we can end up with an 2513 * inversion. Fix it now when the clamps are applied. 2514 */ 2515 if (unlikely(min_util >= max_util)) 2516 return min_util; 2517 2518 return clamp(util, min_util, max_util); 2519 } 2520 2521 /* 2522 * When uclamp is compiled in, the aggregation at rq level is 'turned off' 2523 * by default in the fast path and only gets turned on once userspace performs 2524 * an operation that requires it. 2525 * 2526 * Returns true if userspace opted-in to use uclamp and aggregation at rq level 2527 * hence is active. 2528 */ 2529 static inline bool uclamp_is_used(void) 2530 { 2531 return static_branch_likely(&sched_uclamp_used); 2532 } 2533 #else /* CONFIG_UCLAMP_TASK */ 2534 static inline 2535 unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util, 2536 struct task_struct *p) 2537 { 2538 return util; 2539 } 2540 2541 static inline bool uclamp_is_used(void) 2542 { 2543 return false; 2544 } 2545 #endif /* CONFIG_UCLAMP_TASK */ 2546 2547 #ifdef arch_scale_freq_capacity 2548 # ifndef arch_scale_freq_invariant 2549 # define arch_scale_freq_invariant() true 2550 # endif 2551 #else 2552 # define arch_scale_freq_invariant() false 2553 #endif 2554 2555 #ifdef CONFIG_SMP 2556 static inline unsigned long capacity_orig_of(int cpu) 2557 { 2558 return cpu_rq(cpu)->cpu_capacity_orig; 2559 } 2560 #endif 2561 2562 /** 2563 * enum schedutil_type - CPU utilization type 2564 * @FREQUENCY_UTIL: Utilization used to select frequency 2565 * @ENERGY_UTIL: Utilization used during energy calculation 2566 * 2567 * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time 2568 * need to be aggregated differently depending on the usage made of them. This 2569 * enum is used within schedutil_freq_util() to differentiate the types of 2570 * utilization expected by the callers, and adjust the aggregation accordingly. 2571 */ 2572 enum schedutil_type { 2573 FREQUENCY_UTIL, 2574 ENERGY_UTIL, 2575 }; 2576 2577 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL 2578 2579 unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs, 2580 unsigned long max, enum schedutil_type type, 2581 struct task_struct *p); 2582 2583 static inline unsigned long cpu_bw_dl(struct rq *rq) 2584 { 2585 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT; 2586 } 2587 2588 static inline unsigned long cpu_util_dl(struct rq *rq) 2589 { 2590 return READ_ONCE(rq->avg_dl.util_avg); 2591 } 2592 2593 static inline unsigned long cpu_util_cfs(struct rq *rq) 2594 { 2595 unsigned long util = READ_ONCE(rq->cfs.avg.util_avg); 2596 2597 if (sched_feat(UTIL_EST)) { 2598 util = max_t(unsigned long, util, 2599 READ_ONCE(rq->cfs.avg.util_est.enqueued)); 2600 } 2601 2602 return util; 2603 } 2604 2605 static inline unsigned long cpu_util_rt(struct rq *rq) 2606 { 2607 return READ_ONCE(rq->avg_rt.util_avg); 2608 } 2609 #else /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */ 2610 static inline unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs, 2611 unsigned long max, enum schedutil_type type, 2612 struct task_struct *p) 2613 { 2614 return 0; 2615 } 2616 #endif /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */ 2617 2618 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 2619 static inline unsigned long cpu_util_irq(struct rq *rq) 2620 { 2621 return rq->avg_irq.util_avg; 2622 } 2623 2624 static inline 2625 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 2626 { 2627 util *= (max - irq); 2628 util /= max; 2629 2630 return util; 2631 2632 } 2633 #else 2634 static inline unsigned long cpu_util_irq(struct rq *rq) 2635 { 2636 return 0; 2637 } 2638 2639 static inline 2640 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 2641 { 2642 return util; 2643 } 2644 #endif 2645 2646 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) 2647 2648 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus))) 2649 2650 DECLARE_STATIC_KEY_FALSE(sched_energy_present); 2651 2652 static inline bool sched_energy_enabled(void) 2653 { 2654 return static_branch_unlikely(&sched_energy_present); 2655 } 2656 2657 #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */ 2658 2659 #define perf_domain_span(pd) NULL 2660 static inline bool sched_energy_enabled(void) { return false; } 2661 2662 #endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */ 2663 2664 #ifdef CONFIG_MEMBARRIER 2665 /* 2666 * The scheduler provides memory barriers required by membarrier between: 2667 * - prior user-space memory accesses and store to rq->membarrier_state, 2668 * - store to rq->membarrier_state and following user-space memory accesses. 2669 * In the same way it provides those guarantees around store to rq->curr. 2670 */ 2671 static inline void membarrier_switch_mm(struct rq *rq, 2672 struct mm_struct *prev_mm, 2673 struct mm_struct *next_mm) 2674 { 2675 int membarrier_state; 2676 2677 if (prev_mm == next_mm) 2678 return; 2679 2680 membarrier_state = atomic_read(&next_mm->membarrier_state); 2681 if (READ_ONCE(rq->membarrier_state) == membarrier_state) 2682 return; 2683 2684 WRITE_ONCE(rq->membarrier_state, membarrier_state); 2685 } 2686 #else 2687 static inline void membarrier_switch_mm(struct rq *rq, 2688 struct mm_struct *prev_mm, 2689 struct mm_struct *next_mm) 2690 { 2691 } 2692 #endif 2693 2694 #ifdef CONFIG_SMP 2695 static inline bool is_per_cpu_kthread(struct task_struct *p) 2696 { 2697 if (!(p->flags & PF_KTHREAD)) 2698 return false; 2699 2700 if (p->nr_cpus_allowed != 1) 2701 return false; 2702 2703 return true; 2704 } 2705 #endif 2706 2707 void swake_up_all_locked(struct swait_queue_head *q); 2708 void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait); 2709