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