1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Scheduler internal types and methods: 4 */ 5 #ifndef _KERNEL_SCHED_SCHED_H 6 #define _KERNEL_SCHED_SCHED_H 7 8 #include <linux/sched/affinity.h> 9 #include <linux/sched/autogroup.h> 10 #include <linux/sched/cpufreq.h> 11 #include <linux/sched/deadline.h> 12 #include <linux/sched.h> 13 #include <linux/sched/loadavg.h> 14 #include <linux/sched/mm.h> 15 #include <linux/sched/rseq_api.h> 16 #include <linux/sched/signal.h> 17 #include <linux/sched/smt.h> 18 #include <linux/sched/stat.h> 19 #include <linux/sched/sysctl.h> 20 #include <linux/sched/task_flags.h> 21 #include <linux/sched/task.h> 22 #include <linux/sched/topology.h> 23 #include <linux/atomic.h> 24 #include <linux/bitmap.h> 25 #include <linux/bug.h> 26 #include <linux/capability.h> 27 #include <linux/cgroup_api.h> 28 #include <linux/cgroup.h> 29 #include <linux/context_tracking.h> 30 #include <linux/cpufreq.h> 31 #include <linux/cpumask_api.h> 32 #include <linux/ctype.h> 33 #include <linux/file.h> 34 #include <linux/fs_api.h> 35 #include <linux/hrtimer_api.h> 36 #include <linux/interrupt.h> 37 #include <linux/irq_work.h> 38 #include <linux/jiffies.h> 39 #include <linux/kref_api.h> 40 #include <linux/kthread.h> 41 #include <linux/ktime_api.h> 42 #include <linux/lockdep_api.h> 43 #include <linux/lockdep.h> 44 #include <linux/minmax.h> 45 #include <linux/mm.h> 46 #include <linux/module.h> 47 #include <linux/mutex_api.h> 48 #include <linux/plist.h> 49 #include <linux/poll.h> 50 #include <linux/proc_fs.h> 51 #include <linux/profile.h> 52 #include <linux/psi.h> 53 #include <linux/rcupdate.h> 54 #include <linux/seq_file.h> 55 #include <linux/seqlock.h> 56 #include <linux/softirq.h> 57 #include <linux/spinlock_api.h> 58 #include <linux/static_key.h> 59 #include <linux/stop_machine.h> 60 #include <linux/syscalls_api.h> 61 #include <linux/syscalls.h> 62 #include <linux/tick.h> 63 #include <linux/topology.h> 64 #include <linux/types.h> 65 #include <linux/u64_stats_sync_api.h> 66 #include <linux/uaccess.h> 67 #include <linux/wait_api.h> 68 #include <linux/wait_bit.h> 69 #include <linux/workqueue_api.h> 70 #include <linux/delayacct.h> 71 #include <linux/mmu_context.h> 72 73 #include <trace/events/power.h> 74 #include <trace/events/sched.h> 75 76 #include "../workqueue_internal.h" 77 78 struct rq; 79 struct cfs_rq; 80 struct rt_rq; 81 struct sched_group; 82 struct cpuidle_state; 83 84 #ifdef CONFIG_PARAVIRT 85 # include <asm/paravirt.h> 86 # include <asm/paravirt_api_clock.h> 87 #endif 88 89 #include <asm/barrier.h> 90 91 #include "cpupri.h" 92 #include "cpudeadline.h" 93 94 /* task_struct::on_rq states: */ 95 #define TASK_ON_RQ_QUEUED 1 96 #define TASK_ON_RQ_MIGRATING 2 97 98 extern __read_mostly int scheduler_running; 99 100 extern unsigned long calc_load_update; 101 extern atomic_long_t calc_load_tasks; 102 103 extern void calc_global_load_tick(struct rq *this_rq); 104 extern long calc_load_fold_active(struct rq *this_rq, long adjust); 105 106 extern void call_trace_sched_update_nr_running(struct rq *rq, int count); 107 108 extern int sysctl_sched_rt_period; 109 extern int sysctl_sched_rt_runtime; 110 extern int sched_rr_timeslice; 111 112 /* 113 * Asymmetric CPU capacity bits 114 */ 115 struct asym_cap_data { 116 struct list_head link; 117 struct rcu_head rcu; 118 unsigned long capacity; 119 unsigned long cpus[]; 120 }; 121 122 extern struct list_head asym_cap_list; 123 124 #define cpu_capacity_span(asym_data) to_cpumask((asym_data)->cpus) 125 126 /* 127 * Helpers for converting nanosecond timing to jiffy resolution 128 */ 129 #define NS_TO_JIFFIES(time) ((unsigned long)(time) / (NSEC_PER_SEC/HZ)) 130 131 /* 132 * Increase resolution of nice-level calculations for 64-bit architectures. 133 * The extra resolution improves shares distribution and load balancing of 134 * low-weight task groups (eg. nice +19 on an autogroup), deeper task-group 135 * hierarchies, especially on larger systems. This is not a user-visible change 136 * and does not change the user-interface for setting shares/weights. 137 * 138 * We increase resolution only if we have enough bits to allow this increased 139 * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit 140 * are pretty high and the returns do not justify the increased costs. 141 * 142 * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to 143 * increase coverage and consistency always enable it on 64-bit platforms. 144 */ 145 #ifdef CONFIG_64BIT 146 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT) 147 # define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT) 148 # define scale_load_down(w) \ 149 ({ \ 150 unsigned long __w = (w); \ 151 \ 152 if (__w) \ 153 __w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \ 154 __w; \ 155 }) 156 #else 157 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT) 158 # define scale_load(w) (w) 159 # define scale_load_down(w) (w) 160 #endif 161 162 /* 163 * Task weight (visible to users) and its load (invisible to users) have 164 * independent resolution, but they should be well calibrated. We use 165 * scale_load() and scale_load_down(w) to convert between them. The 166 * following must be true: 167 * 168 * scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD 169 * 170 */ 171 #define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT) 172 173 /* 174 * Single value that decides SCHED_DEADLINE internal math precision. 175 * 10 -> just above 1us 176 * 9 -> just above 0.5us 177 */ 178 #define DL_SCALE 10 179 180 /* 181 * Single value that denotes runtime == period, ie unlimited time. 182 */ 183 #define RUNTIME_INF ((u64)~0ULL) 184 185 static inline int idle_policy(int policy) 186 { 187 return policy == SCHED_IDLE; 188 } 189 190 static inline int normal_policy(int policy) 191 { 192 #ifdef CONFIG_SCHED_CLASS_EXT 193 if (policy == SCHED_EXT) 194 return true; 195 #endif 196 return policy == SCHED_NORMAL; 197 } 198 199 static inline int fair_policy(int policy) 200 { 201 return normal_policy(policy) || policy == SCHED_BATCH; 202 } 203 204 static inline int rt_policy(int policy) 205 { 206 return policy == SCHED_FIFO || policy == SCHED_RR; 207 } 208 209 static inline int dl_policy(int policy) 210 { 211 return policy == SCHED_DEADLINE; 212 } 213 214 static inline bool valid_policy(int policy) 215 { 216 return idle_policy(policy) || fair_policy(policy) || 217 rt_policy(policy) || dl_policy(policy); 218 } 219 220 static inline int task_has_idle_policy(struct task_struct *p) 221 { 222 return idle_policy(p->policy); 223 } 224 225 static inline int task_has_rt_policy(struct task_struct *p) 226 { 227 return rt_policy(p->policy); 228 } 229 230 static inline int task_has_dl_policy(struct task_struct *p) 231 { 232 return dl_policy(p->policy); 233 } 234 235 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT) 236 237 static inline void update_avg(u64 *avg, u64 sample) 238 { 239 s64 diff = sample - *avg; 240 241 *avg += diff / 8; 242 } 243 244 /* 245 * Shifting a value by an exponent greater *or equal* to the size of said value 246 * is UB; cap at size-1. 247 */ 248 #define shr_bound(val, shift) \ 249 (val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1)) 250 251 /* 252 * cgroup weight knobs should use the common MIN, DFL and MAX values which are 253 * 1, 100 and 10000 respectively. While it loses a bit of range on both ends, it 254 * maps pretty well onto the shares value used by scheduler and the round-trip 255 * conversions preserve the original value over the entire range. 256 */ 257 static inline unsigned long sched_weight_from_cgroup(unsigned long cgrp_weight) 258 { 259 return DIV_ROUND_CLOSEST_ULL(cgrp_weight * 1024, CGROUP_WEIGHT_DFL); 260 } 261 262 static inline unsigned long sched_weight_to_cgroup(unsigned long weight) 263 { 264 return clamp_t(unsigned long, 265 DIV_ROUND_CLOSEST_ULL(weight * CGROUP_WEIGHT_DFL, 1024), 266 CGROUP_WEIGHT_MIN, CGROUP_WEIGHT_MAX); 267 } 268 269 /* 270 * !! For sched_setattr_nocheck() (kernel) only !! 271 * 272 * This is actually gross. :( 273 * 274 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE 275 * tasks, but still be able to sleep. We need this on platforms that cannot 276 * atomically change clock frequency. Remove once fast switching will be 277 * available on such platforms. 278 * 279 * SUGOV stands for SchedUtil GOVernor. 280 */ 281 #define SCHED_FLAG_SUGOV 0x10000000 282 283 #define SCHED_DL_FLAGS (SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV) 284 285 static inline bool dl_entity_is_special(const struct sched_dl_entity *dl_se) 286 { 287 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL 288 return unlikely(dl_se->flags & SCHED_FLAG_SUGOV); 289 #else 290 return false; 291 #endif 292 } 293 294 /* 295 * Tells if entity @a should preempt entity @b. 296 */ 297 static inline bool dl_entity_preempt(const struct sched_dl_entity *a, 298 const struct sched_dl_entity *b) 299 { 300 return dl_entity_is_special(a) || 301 dl_time_before(a->deadline, b->deadline); 302 } 303 304 /* 305 * This is the priority-queue data structure of the RT scheduling class: 306 */ 307 struct rt_prio_array { 308 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */ 309 struct list_head queue[MAX_RT_PRIO]; 310 }; 311 312 struct rt_bandwidth { 313 /* nests inside the rq lock: */ 314 raw_spinlock_t rt_runtime_lock; 315 ktime_t rt_period; 316 u64 rt_runtime; 317 struct hrtimer rt_period_timer; 318 unsigned int rt_period_active; 319 }; 320 321 static inline int dl_bandwidth_enabled(void) 322 { 323 return sysctl_sched_rt_runtime >= 0; 324 } 325 326 /* 327 * To keep the bandwidth of -deadline tasks under control 328 * we need some place where: 329 * - store the maximum -deadline bandwidth of each cpu; 330 * - cache the fraction of bandwidth that is currently allocated in 331 * each root domain; 332 * 333 * This is all done in the data structure below. It is similar to the 334 * one used for RT-throttling (rt_bandwidth), with the main difference 335 * that, since here we are only interested in admission control, we 336 * do not decrease any runtime while the group "executes", neither we 337 * need a timer to replenish it. 338 * 339 * With respect to SMP, bandwidth is given on a per root domain basis, 340 * meaning that: 341 * - bw (< 100%) is the deadline bandwidth of each CPU; 342 * - total_bw is the currently allocated bandwidth in each root domain; 343 */ 344 struct dl_bw { 345 raw_spinlock_t lock; 346 u64 bw; 347 u64 total_bw; 348 }; 349 350 extern void init_dl_bw(struct dl_bw *dl_b); 351 extern int sched_dl_global_validate(void); 352 extern void sched_dl_do_global(void); 353 extern int sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr); 354 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr); 355 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr); 356 extern bool __checkparam_dl(const struct sched_attr *attr); 357 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr); 358 extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 359 extern int dl_bw_deactivate(int cpu); 360 extern s64 dl_scaled_delta_exec(struct rq *rq, struct sched_dl_entity *dl_se, s64 delta_exec); 361 /* 362 * SCHED_DEADLINE supports servers (nested scheduling) with the following 363 * interface: 364 * 365 * dl_se::rq -- runqueue we belong to. 366 * 367 * dl_se::server_pick() -- nested pick_next_task(); we yield the period if this 368 * returns NULL. 369 * 370 * dl_server_update() -- called from update_curr_common(), propagates runtime 371 * to the server. 372 * 373 * dl_server_start() -- start the server when it has tasks; it will stop 374 * automatically when there are no more tasks, per 375 * dl_se::server_pick() returning NULL. 376 * 377 * dl_server_stop() -- (force) stop the server; use when updating 378 * parameters. 379 * 380 * dl_server_init() -- initializes the server. 381 * 382 * When started the dl_server will (per dl_defer) schedule a timer for its 383 * zero-laxity point -- that is, unlike regular EDF tasks which run ASAP, a 384 * server will run at the very end of its period. 385 * 386 * This is done such that any runtime from the target class can be accounted 387 * against the server -- through dl_server_update() above -- such that when it 388 * becomes time to run, it might already be out of runtime and get deferred 389 * until the next period. In this case dl_server_timer() will alternate 390 * between defer and replenish but never actually enqueue the server. 391 * 392 * Only when the target class does not manage to exhaust the server's runtime 393 * (there's actualy starvation in the given period), will the dl_server get on 394 * the runqueue. Once queued it will pick tasks from the target class and run 395 * them until either its runtime is exhaused, at which point its back to 396 * dl_server_timer, or until there are no more tasks to run, at which point 397 * the dl_server stops itself. 398 * 399 * By stopping at this point the dl_server retains bandwidth, which, if a new 400 * task wakes up imminently (starting the server again), can be used -- 401 * subject to CBS wakeup rules -- without having to wait for the next period. 402 * 403 * Additionally, because of the dl_defer behaviour the start/stop behaviour is 404 * naturally thottled to once per period, avoiding high context switch 405 * workloads from spamming the hrtimer program/cancel paths. 406 */ 407 extern void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec); 408 extern void dl_server_start(struct sched_dl_entity *dl_se); 409 extern void dl_server_stop(struct sched_dl_entity *dl_se); 410 extern void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq, 411 dl_server_pick_f pick_task); 412 extern void sched_init_dl_servers(void); 413 414 extern void dl_server_update_idle_time(struct rq *rq, 415 struct task_struct *p); 416 extern void fair_server_init(struct rq *rq); 417 extern void __dl_server_attach_root(struct sched_dl_entity *dl_se, struct rq *rq); 418 extern int dl_server_apply_params(struct sched_dl_entity *dl_se, 419 u64 runtime, u64 period, bool init); 420 421 static inline bool dl_server_active(struct sched_dl_entity *dl_se) 422 { 423 return dl_se->dl_server_active; 424 } 425 426 #ifdef CONFIG_CGROUP_SCHED 427 428 extern struct list_head task_groups; 429 430 #ifdef CONFIG_GROUP_SCHED_BANDWIDTH 431 extern const u64 max_bw_quota_period_us; 432 433 /* 434 * default period for group bandwidth. 435 * default: 0.1s, units: microseconds 436 */ 437 static inline u64 default_bw_period_us(void) 438 { 439 return 100000ULL; 440 } 441 #endif /* CONFIG_GROUP_SCHED_BANDWIDTH */ 442 443 struct cfs_bandwidth { 444 #ifdef CONFIG_CFS_BANDWIDTH 445 raw_spinlock_t lock; 446 ktime_t period; 447 u64 quota; 448 u64 runtime; 449 u64 burst; 450 u64 runtime_snap; 451 s64 hierarchical_quota; 452 453 u8 idle; 454 u8 period_active; 455 u8 slack_started; 456 struct hrtimer period_timer; 457 struct hrtimer slack_timer; 458 struct list_head throttled_cfs_rq; 459 460 /* Statistics: */ 461 int nr_periods; 462 int nr_throttled; 463 int nr_burst; 464 u64 throttled_time; 465 u64 burst_time; 466 #endif /* CONFIG_CFS_BANDWIDTH */ 467 }; 468 469 /* Task group related information */ 470 struct task_group { 471 struct cgroup_subsys_state css; 472 473 #ifdef CONFIG_GROUP_SCHED_WEIGHT 474 /* A positive value indicates that this is a SCHED_IDLE group. */ 475 int idle; 476 #endif 477 478 #ifdef CONFIG_FAIR_GROUP_SCHED 479 /* schedulable entities of this group on each CPU */ 480 struct sched_entity **se; 481 /* runqueue "owned" by this group on each CPU */ 482 struct cfs_rq **cfs_rq; 483 unsigned long shares; 484 /* 485 * load_avg can be heavily contended at clock tick time, so put 486 * it in its own cache-line separated from the fields above which 487 * will also be accessed at each tick. 488 */ 489 atomic_long_t load_avg ____cacheline_aligned; 490 #endif /* CONFIG_FAIR_GROUP_SCHED */ 491 492 #ifdef CONFIG_RT_GROUP_SCHED 493 struct sched_rt_entity **rt_se; 494 struct rt_rq **rt_rq; 495 496 struct rt_bandwidth rt_bandwidth; 497 #endif 498 499 struct scx_task_group scx; 500 501 struct rcu_head rcu; 502 struct list_head list; 503 504 struct task_group *parent; 505 struct list_head siblings; 506 struct list_head children; 507 508 #ifdef CONFIG_SCHED_AUTOGROUP 509 struct autogroup *autogroup; 510 #endif 511 512 struct cfs_bandwidth cfs_bandwidth; 513 514 #ifdef CONFIG_UCLAMP_TASK_GROUP 515 /* The two decimal precision [%] value requested from user-space */ 516 unsigned int uclamp_pct[UCLAMP_CNT]; 517 /* Clamp values requested for a task group */ 518 struct uclamp_se uclamp_req[UCLAMP_CNT]; 519 /* Effective clamp values used for a task group */ 520 struct uclamp_se uclamp[UCLAMP_CNT]; 521 #endif 522 523 }; 524 525 #ifdef CONFIG_GROUP_SCHED_WEIGHT 526 #define ROOT_TASK_GROUP_LOAD NICE_0_LOAD 527 528 /* 529 * A weight of 0 or 1 can cause arithmetics problems. 530 * A weight of a cfs_rq is the sum of weights of which entities 531 * are queued on this cfs_rq, so a weight of a entity should not be 532 * too large, so as the shares value of a task group. 533 * (The default weight is 1024 - so there's no practical 534 * limitation from this.) 535 */ 536 #define MIN_SHARES (1UL << 1) 537 #define MAX_SHARES (1UL << 18) 538 #endif 539 540 typedef int (*tg_visitor)(struct task_group *, void *); 541 542 extern int walk_tg_tree_from(struct task_group *from, 543 tg_visitor down, tg_visitor up, void *data); 544 545 /* 546 * Iterate the full tree, calling @down when first entering a node and @up when 547 * leaving it for the final time. 548 * 549 * Caller must hold rcu_lock or sufficient equivalent. 550 */ 551 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data) 552 { 553 return walk_tg_tree_from(&root_task_group, down, up, data); 554 } 555 556 static inline struct task_group *css_tg(struct cgroup_subsys_state *css) 557 { 558 return css ? container_of(css, struct task_group, css) : NULL; 559 } 560 561 extern int tg_nop(struct task_group *tg, void *data); 562 563 #ifdef CONFIG_FAIR_GROUP_SCHED 564 extern void free_fair_sched_group(struct task_group *tg); 565 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent); 566 extern void online_fair_sched_group(struct task_group *tg); 567 extern void unregister_fair_sched_group(struct task_group *tg); 568 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 569 static inline void free_fair_sched_group(struct task_group *tg) { } 570 static inline int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) 571 { 572 return 1; 573 } 574 static inline void online_fair_sched_group(struct task_group *tg) { } 575 static inline void unregister_fair_sched_group(struct task_group *tg) { } 576 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 577 578 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, 579 struct sched_entity *se, int cpu, 580 struct sched_entity *parent); 581 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b, struct cfs_bandwidth *parent); 582 583 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b); 584 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b); 585 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq); 586 extern bool cfs_task_bw_constrained(struct task_struct *p); 587 588 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, 589 struct sched_rt_entity *rt_se, int cpu, 590 struct sched_rt_entity *parent); 591 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us); 592 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us); 593 extern long sched_group_rt_runtime(struct task_group *tg); 594 extern long sched_group_rt_period(struct task_group *tg); 595 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk); 596 597 extern struct task_group *sched_create_group(struct task_group *parent); 598 extern void sched_online_group(struct task_group *tg, 599 struct task_group *parent); 600 extern void sched_destroy_group(struct task_group *tg); 601 extern void sched_release_group(struct task_group *tg); 602 603 extern void sched_move_task(struct task_struct *tsk, bool for_autogroup); 604 605 #ifdef CONFIG_FAIR_GROUP_SCHED 606 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); 607 608 extern int sched_group_set_idle(struct task_group *tg, long idle); 609 610 extern void set_task_rq_fair(struct sched_entity *se, 611 struct cfs_rq *prev, struct cfs_rq *next); 612 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 613 static inline int sched_group_set_shares(struct task_group *tg, unsigned long shares) { return 0; } 614 static inline int sched_group_set_idle(struct task_group *tg, long idle) { return 0; } 615 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 616 617 #else /* !CONFIG_CGROUP_SCHED: */ 618 619 struct cfs_bandwidth { }; 620 621 static inline bool cfs_task_bw_constrained(struct task_struct *p) { return false; } 622 623 #endif /* !CONFIG_CGROUP_SCHED */ 624 625 extern void unregister_rt_sched_group(struct task_group *tg); 626 extern void free_rt_sched_group(struct task_group *tg); 627 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent); 628 629 /* 630 * u64_u32_load/u64_u32_store 631 * 632 * Use a copy of a u64 value to protect against data race. This is only 633 * applicable for 32-bits architectures. 634 */ 635 #ifdef CONFIG_64BIT 636 # define u64_u32_load_copy(var, copy) var 637 # define u64_u32_store_copy(var, copy, val) (var = val) 638 #else 639 # define u64_u32_load_copy(var, copy) \ 640 ({ \ 641 u64 __val, __val_copy; \ 642 do { \ 643 __val_copy = copy; \ 644 /* \ 645 * paired with u64_u32_store_copy(), ordering access \ 646 * to var and copy. \ 647 */ \ 648 smp_rmb(); \ 649 __val = var; \ 650 } while (__val != __val_copy); \ 651 __val; \ 652 }) 653 # define u64_u32_store_copy(var, copy, val) \ 654 do { \ 655 typeof(val) __val = (val); \ 656 var = __val; \ 657 /* \ 658 * paired with u64_u32_load_copy(), ordering access to var and \ 659 * copy. \ 660 */ \ 661 smp_wmb(); \ 662 copy = __val; \ 663 } while (0) 664 #endif 665 # define u64_u32_load(var) u64_u32_load_copy(var, var##_copy) 666 # define u64_u32_store(var, val) u64_u32_store_copy(var, var##_copy, val) 667 668 struct balance_callback { 669 struct balance_callback *next; 670 void (*func)(struct rq *rq); 671 }; 672 673 /* CFS-related fields in a runqueue */ 674 struct cfs_rq { 675 struct load_weight load; 676 unsigned int nr_queued; 677 unsigned int h_nr_queued; /* SCHED_{NORMAL,BATCH,IDLE} */ 678 unsigned int h_nr_runnable; /* SCHED_{NORMAL,BATCH,IDLE} */ 679 unsigned int h_nr_idle; /* SCHED_IDLE */ 680 681 s64 avg_vruntime; 682 u64 avg_load; 683 684 u64 min_vruntime; 685 #ifdef CONFIG_SCHED_CORE 686 unsigned int forceidle_seq; 687 u64 min_vruntime_fi; 688 #endif 689 690 struct rb_root_cached tasks_timeline; 691 692 /* 693 * 'curr' points to currently running entity on this cfs_rq. 694 * It is set to NULL otherwise (i.e when none are currently running). 695 */ 696 struct sched_entity *curr; 697 struct sched_entity *next; 698 699 /* 700 * CFS load tracking 701 */ 702 struct sched_avg avg; 703 #ifndef CONFIG_64BIT 704 u64 last_update_time_copy; 705 #endif 706 struct { 707 raw_spinlock_t lock ____cacheline_aligned; 708 int nr; 709 unsigned long load_avg; 710 unsigned long util_avg; 711 unsigned long runnable_avg; 712 } removed; 713 714 #ifdef CONFIG_FAIR_GROUP_SCHED 715 u64 last_update_tg_load_avg; 716 unsigned long tg_load_avg_contrib; 717 long propagate; 718 long prop_runnable_sum; 719 720 /* 721 * h_load = weight * f(tg) 722 * 723 * Where f(tg) is the recursive weight fraction assigned to 724 * this group. 725 */ 726 unsigned long h_load; 727 u64 last_h_load_update; 728 struct sched_entity *h_load_next; 729 #endif /* CONFIG_FAIR_GROUP_SCHED */ 730 731 #ifdef CONFIG_FAIR_GROUP_SCHED 732 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */ 733 734 /* 735 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in 736 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities 737 * (like users, containers etc.) 738 * 739 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU. 740 * This list is used during load balance. 741 */ 742 int on_list; 743 struct list_head leaf_cfs_rq_list; 744 struct task_group *tg; /* group that "owns" this runqueue */ 745 746 /* Locally cached copy of our task_group's idle value */ 747 int idle; 748 749 #ifdef CONFIG_CFS_BANDWIDTH 750 int runtime_enabled; 751 s64 runtime_remaining; 752 753 u64 throttled_pelt_idle; 754 #ifndef CONFIG_64BIT 755 u64 throttled_pelt_idle_copy; 756 #endif 757 u64 throttled_clock; 758 u64 throttled_clock_pelt; 759 u64 throttled_clock_pelt_time; 760 u64 throttled_clock_self; 761 u64 throttled_clock_self_time; 762 bool throttled:1; 763 bool pelt_clock_throttled:1; 764 int throttle_count; 765 struct list_head throttled_list; 766 struct list_head throttled_csd_list; 767 struct list_head throttled_limbo_list; 768 #endif /* CONFIG_CFS_BANDWIDTH */ 769 #endif /* CONFIG_FAIR_GROUP_SCHED */ 770 }; 771 772 #ifdef CONFIG_SCHED_CLASS_EXT 773 /* scx_rq->flags, protected by the rq lock */ 774 enum scx_rq_flags { 775 /* 776 * A hotplugged CPU starts scheduling before rq_online_scx(). Track 777 * ops.cpu_on/offline() state so that ops.enqueue/dispatch() are called 778 * only while the BPF scheduler considers the CPU to be online. 779 */ 780 SCX_RQ_ONLINE = 1 << 0, 781 SCX_RQ_CAN_STOP_TICK = 1 << 1, 782 SCX_RQ_BAL_KEEP = 1 << 3, /* balance decided to keep current */ 783 SCX_RQ_BYPASSING = 1 << 4, 784 SCX_RQ_CLK_VALID = 1 << 5, /* RQ clock is fresh and valid */ 785 SCX_RQ_BAL_CB_PENDING = 1 << 6, /* must queue a cb after dispatching */ 786 787 SCX_RQ_IN_WAKEUP = 1 << 16, 788 SCX_RQ_IN_BALANCE = 1 << 17, 789 }; 790 791 struct scx_rq { 792 struct scx_dispatch_q local_dsq; 793 struct list_head runnable_list; /* runnable tasks on this rq */ 794 struct list_head ddsp_deferred_locals; /* deferred ddsps from enq */ 795 unsigned long ops_qseq; 796 u64 extra_enq_flags; /* see move_task_to_local_dsq() */ 797 u32 nr_running; 798 u32 cpuperf_target; /* [0, SCHED_CAPACITY_SCALE] */ 799 bool cpu_released; 800 u32 flags; 801 u64 clock; /* current per-rq clock -- see scx_bpf_now() */ 802 cpumask_var_t cpus_to_kick; 803 cpumask_var_t cpus_to_kick_if_idle; 804 cpumask_var_t cpus_to_preempt; 805 cpumask_var_t cpus_to_wait; 806 unsigned long pnt_seq; 807 struct balance_callback deferred_bal_cb; 808 struct irq_work deferred_irq_work; 809 struct irq_work kick_cpus_irq_work; 810 }; 811 #endif /* CONFIG_SCHED_CLASS_EXT */ 812 813 static inline int rt_bandwidth_enabled(void) 814 { 815 return sysctl_sched_rt_runtime >= 0; 816 } 817 818 /* RT IPI pull logic requires IRQ_WORK */ 819 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP) 820 # define HAVE_RT_PUSH_IPI 821 #endif 822 823 /* Real-Time classes' related field in a runqueue: */ 824 struct rt_rq { 825 struct rt_prio_array active; 826 unsigned int rt_nr_running; 827 unsigned int rr_nr_running; 828 struct { 829 int curr; /* highest queued rt task prio */ 830 int next; /* next highest */ 831 } highest_prio; 832 bool overloaded; 833 struct plist_head pushable_tasks; 834 835 int rt_queued; 836 837 #ifdef CONFIG_RT_GROUP_SCHED 838 int rt_throttled; 839 u64 rt_time; /* consumed RT time, goes up in update_curr_rt */ 840 u64 rt_runtime; /* allotted RT time, "slice" from rt_bandwidth, RT sharing/balancing */ 841 /* Nests inside the rq lock: */ 842 raw_spinlock_t rt_runtime_lock; 843 844 unsigned int rt_nr_boosted; 845 846 struct rq *rq; /* this is always top-level rq, cache? */ 847 #endif 848 #ifdef CONFIG_CGROUP_SCHED 849 struct task_group *tg; /* this tg has "this" rt_rq on given CPU for runnable entities */ 850 #endif 851 }; 852 853 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq) 854 { 855 return rt_rq->rt_queued && rt_rq->rt_nr_running; 856 } 857 858 /* Deadline class' related fields in a runqueue */ 859 struct dl_rq { 860 /* runqueue is an rbtree, ordered by deadline */ 861 struct rb_root_cached root; 862 863 unsigned int dl_nr_running; 864 865 /* 866 * Deadline values of the currently executing and the 867 * earliest ready task on this rq. Caching these facilitates 868 * the decision whether or not a ready but not running task 869 * should migrate somewhere else. 870 */ 871 struct { 872 u64 curr; 873 u64 next; 874 } earliest_dl; 875 876 bool overloaded; 877 878 /* 879 * Tasks on this rq that can be pushed away. They are kept in 880 * an rb-tree, ordered by tasks' deadlines, with caching 881 * of the leftmost (earliest deadline) element. 882 */ 883 struct rb_root_cached pushable_dl_tasks_root; 884 885 /* 886 * "Active utilization" for this runqueue: increased when a 887 * task wakes up (becomes TASK_RUNNING) and decreased when a 888 * task blocks 889 */ 890 u64 running_bw; 891 892 /* 893 * Utilization of the tasks "assigned" to this runqueue (including 894 * the tasks that are in runqueue and the tasks that executed on this 895 * CPU and blocked). Increased when a task moves to this runqueue, and 896 * decreased when the task moves away (migrates, changes scheduling 897 * policy, or terminates). 898 * This is needed to compute the "inactive utilization" for the 899 * runqueue (inactive utilization = this_bw - running_bw). 900 */ 901 u64 this_bw; 902 u64 extra_bw; 903 904 /* 905 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM 906 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB). 907 */ 908 u64 max_bw; 909 910 /* 911 * Inverse of the fraction of CPU utilization that can be reclaimed 912 * by the GRUB algorithm. 913 */ 914 u64 bw_ratio; 915 }; 916 917 #ifdef CONFIG_FAIR_GROUP_SCHED 918 919 /* An entity is a task if it doesn't "own" a runqueue */ 920 #define entity_is_task(se) (!se->my_q) 921 922 static inline void se_update_runnable(struct sched_entity *se) 923 { 924 if (!entity_is_task(se)) 925 se->runnable_weight = se->my_q->h_nr_runnable; 926 } 927 928 static inline long se_runnable(struct sched_entity *se) 929 { 930 if (se->sched_delayed) 931 return false; 932 933 if (entity_is_task(se)) 934 return !!se->on_rq; 935 else 936 return se->runnable_weight; 937 } 938 939 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 940 941 #define entity_is_task(se) 1 942 943 static inline void se_update_runnable(struct sched_entity *se) { } 944 945 static inline long se_runnable(struct sched_entity *se) 946 { 947 if (se->sched_delayed) 948 return false; 949 950 return !!se->on_rq; 951 } 952 953 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 954 955 /* 956 * XXX we want to get rid of these helpers and use the full load resolution. 957 */ 958 static inline long se_weight(struct sched_entity *se) 959 { 960 return scale_load_down(se->load.weight); 961 } 962 963 964 static inline bool sched_asym_prefer(int a, int b) 965 { 966 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b); 967 } 968 969 struct perf_domain { 970 struct em_perf_domain *em_pd; 971 struct perf_domain *next; 972 struct rcu_head rcu; 973 }; 974 975 /* 976 * We add the notion of a root-domain which will be used to define per-domain 977 * variables. Each exclusive cpuset essentially defines an island domain by 978 * fully partitioning the member CPUs from any other cpuset. Whenever a new 979 * exclusive cpuset is created, we also create and attach a new root-domain 980 * object. 981 * 982 */ 983 struct root_domain { 984 atomic_t refcount; 985 atomic_t rto_count; 986 struct rcu_head rcu; 987 cpumask_var_t span; 988 cpumask_var_t online; 989 990 /* 991 * Indicate pullable load on at least one CPU, e.g: 992 * - More than one runnable task 993 * - Running task is misfit 994 */ 995 bool overloaded; 996 997 /* Indicate one or more CPUs over-utilized (tipping point) */ 998 bool overutilized; 999 1000 /* 1001 * The bit corresponding to a CPU gets set here if such CPU has more 1002 * than one runnable -deadline task (as it is below for RT tasks). 1003 */ 1004 cpumask_var_t dlo_mask; 1005 atomic_t dlo_count; 1006 struct dl_bw dl_bw; 1007 struct cpudl cpudl; 1008 1009 /* 1010 * Indicate whether a root_domain's dl_bw has been checked or 1011 * updated. It's monotonously increasing value. 1012 * 1013 * Also, some corner cases, like 'wrap around' is dangerous, but given 1014 * that u64 is 'big enough'. So that shouldn't be a concern. 1015 */ 1016 u64 visit_cookie; 1017 1018 #ifdef HAVE_RT_PUSH_IPI 1019 /* 1020 * For IPI pull requests, loop across the rto_mask. 1021 */ 1022 struct irq_work rto_push_work; 1023 raw_spinlock_t rto_lock; 1024 /* These are only updated and read within rto_lock */ 1025 int rto_loop; 1026 int rto_cpu; 1027 /* These atomics are updated outside of a lock */ 1028 atomic_t rto_loop_next; 1029 atomic_t rto_loop_start; 1030 #endif /* HAVE_RT_PUSH_IPI */ 1031 /* 1032 * The "RT overload" flag: it gets set if a CPU has more than 1033 * one runnable RT task. 1034 */ 1035 cpumask_var_t rto_mask; 1036 struct cpupri cpupri; 1037 1038 /* 1039 * NULL-terminated list of performance domains intersecting with the 1040 * CPUs of the rd. Protected by RCU. 1041 */ 1042 struct perf_domain __rcu *pd; 1043 }; 1044 1045 extern void init_defrootdomain(void); 1046 extern int sched_init_domains(const struct cpumask *cpu_map); 1047 extern void rq_attach_root(struct rq *rq, struct root_domain *rd); 1048 extern void sched_get_rd(struct root_domain *rd); 1049 extern void sched_put_rd(struct root_domain *rd); 1050 1051 static inline int get_rd_overloaded(struct root_domain *rd) 1052 { 1053 return READ_ONCE(rd->overloaded); 1054 } 1055 1056 static inline void set_rd_overloaded(struct root_domain *rd, int status) 1057 { 1058 if (get_rd_overloaded(rd) != status) 1059 WRITE_ONCE(rd->overloaded, status); 1060 } 1061 1062 #ifdef HAVE_RT_PUSH_IPI 1063 extern void rto_push_irq_work_func(struct irq_work *work); 1064 #endif 1065 1066 #ifdef CONFIG_UCLAMP_TASK 1067 /* 1068 * struct uclamp_bucket - Utilization clamp bucket 1069 * @value: utilization clamp value for tasks on this clamp bucket 1070 * @tasks: number of RUNNABLE tasks on this clamp bucket 1071 * 1072 * Keep track of how many tasks are RUNNABLE for a given utilization 1073 * clamp value. 1074 */ 1075 struct uclamp_bucket { 1076 unsigned long value : bits_per(SCHED_CAPACITY_SCALE); 1077 unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE); 1078 }; 1079 1080 /* 1081 * struct uclamp_rq - rq's utilization clamp 1082 * @value: currently active clamp values for a rq 1083 * @bucket: utilization clamp buckets affecting a rq 1084 * 1085 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values. 1086 * A clamp value is affecting a rq when there is at least one task RUNNABLE 1087 * (or actually running) with that value. 1088 * 1089 * There are up to UCLAMP_CNT possible different clamp values, currently there 1090 * are only two: minimum utilization and maximum utilization. 1091 * 1092 * All utilization clamping values are MAX aggregated, since: 1093 * - for util_min: we want to run the CPU at least at the max of the minimum 1094 * utilization required by its currently RUNNABLE tasks. 1095 * - for util_max: we want to allow the CPU to run up to the max of the 1096 * maximum utilization allowed by its currently RUNNABLE tasks. 1097 * 1098 * Since on each system we expect only a limited number of different 1099 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track 1100 * the metrics required to compute all the per-rq utilization clamp values. 1101 */ 1102 struct uclamp_rq { 1103 unsigned int value; 1104 struct uclamp_bucket bucket[UCLAMP_BUCKETS]; 1105 }; 1106 1107 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used); 1108 #endif /* CONFIG_UCLAMP_TASK */ 1109 1110 /* 1111 * This is the main, per-CPU runqueue data structure. 1112 * 1113 * Locking rule: those places that want to lock multiple runqueues 1114 * (such as the load balancing or the thread migration code), lock 1115 * acquire operations must be ordered by ascending &runqueue. 1116 */ 1117 struct rq { 1118 /* runqueue lock: */ 1119 raw_spinlock_t __lock; 1120 1121 /* Per class runqueue modification mask; bits in class order. */ 1122 unsigned int queue_mask; 1123 unsigned int nr_running; 1124 #ifdef CONFIG_NUMA_BALANCING 1125 unsigned int nr_numa_running; 1126 unsigned int nr_preferred_running; 1127 unsigned int numa_migrate_on; 1128 #endif 1129 #ifdef CONFIG_NO_HZ_COMMON 1130 unsigned long last_blocked_load_update_tick; 1131 unsigned int has_blocked_load; 1132 call_single_data_t nohz_csd; 1133 unsigned int nohz_tick_stopped; 1134 atomic_t nohz_flags; 1135 #endif /* CONFIG_NO_HZ_COMMON */ 1136 1137 unsigned int ttwu_pending; 1138 u64 nr_switches; 1139 1140 #ifdef CONFIG_UCLAMP_TASK 1141 /* Utilization clamp values based on CPU's RUNNABLE tasks */ 1142 struct uclamp_rq uclamp[UCLAMP_CNT] ____cacheline_aligned; 1143 unsigned int uclamp_flags; 1144 #define UCLAMP_FLAG_IDLE 0x01 1145 #endif 1146 1147 struct cfs_rq cfs; 1148 struct rt_rq rt; 1149 struct dl_rq dl; 1150 #ifdef CONFIG_SCHED_CLASS_EXT 1151 struct scx_rq scx; 1152 #endif 1153 1154 struct sched_dl_entity fair_server; 1155 1156 #ifdef CONFIG_FAIR_GROUP_SCHED 1157 /* list of leaf cfs_rq on this CPU: */ 1158 struct list_head leaf_cfs_rq_list; 1159 struct list_head *tmp_alone_branch; 1160 #endif /* CONFIG_FAIR_GROUP_SCHED */ 1161 1162 /* 1163 * This is part of a global counter where only the total sum 1164 * over all CPUs matters. A task can increase this counter on 1165 * one CPU and if it got migrated afterwards it may decrease 1166 * it on another CPU. Always updated under the runqueue lock: 1167 */ 1168 unsigned long nr_uninterruptible; 1169 1170 #ifdef CONFIG_SCHED_PROXY_EXEC 1171 struct task_struct __rcu *donor; /* Scheduling context */ 1172 struct task_struct __rcu *curr; /* Execution context */ 1173 #else 1174 union { 1175 struct task_struct __rcu *donor; /* Scheduler context */ 1176 struct task_struct __rcu *curr; /* Execution context */ 1177 }; 1178 #endif 1179 struct sched_dl_entity *dl_server; 1180 struct task_struct *idle; 1181 struct task_struct *stop; 1182 unsigned long next_balance; 1183 struct mm_struct *prev_mm; 1184 1185 unsigned int clock_update_flags; 1186 u64 clock; 1187 /* Ensure that all clocks are in the same cache line */ 1188 u64 clock_task ____cacheline_aligned; 1189 u64 clock_pelt; 1190 unsigned long lost_idle_time; 1191 u64 clock_pelt_idle; 1192 u64 clock_idle; 1193 #ifndef CONFIG_64BIT 1194 u64 clock_pelt_idle_copy; 1195 u64 clock_idle_copy; 1196 #endif 1197 1198 atomic_t nr_iowait; 1199 1200 u64 last_seen_need_resched_ns; 1201 int ticks_without_resched; 1202 1203 #ifdef CONFIG_MEMBARRIER 1204 int membarrier_state; 1205 #endif 1206 1207 struct root_domain *rd; 1208 struct sched_domain __rcu *sd; 1209 1210 unsigned long cpu_capacity; 1211 1212 struct balance_callback *balance_callback; 1213 1214 unsigned char nohz_idle_balance; 1215 unsigned char idle_balance; 1216 1217 unsigned long misfit_task_load; 1218 1219 /* For active balancing */ 1220 int active_balance; 1221 int push_cpu; 1222 struct cpu_stop_work active_balance_work; 1223 1224 /* CPU of this runqueue: */ 1225 int cpu; 1226 int online; 1227 1228 struct list_head cfs_tasks; 1229 1230 struct sched_avg avg_rt; 1231 struct sched_avg avg_dl; 1232 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 1233 struct sched_avg avg_irq; 1234 #endif 1235 #ifdef CONFIG_SCHED_HW_PRESSURE 1236 struct sched_avg avg_hw; 1237 #endif 1238 u64 idle_stamp; 1239 u64 avg_idle; 1240 1241 /* This is used to determine avg_idle's max value */ 1242 u64 max_idle_balance_cost; 1243 1244 #ifdef CONFIG_HOTPLUG_CPU 1245 struct rcuwait hotplug_wait; 1246 #endif 1247 1248 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 1249 u64 prev_irq_time; 1250 u64 psi_irq_time; 1251 #endif 1252 #ifdef CONFIG_PARAVIRT 1253 u64 prev_steal_time; 1254 #endif 1255 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING 1256 u64 prev_steal_time_rq; 1257 #endif 1258 1259 /* calc_load related fields */ 1260 unsigned long calc_load_update; 1261 long calc_load_active; 1262 1263 #ifdef CONFIG_SCHED_HRTICK 1264 call_single_data_t hrtick_csd; 1265 struct hrtimer hrtick_timer; 1266 ktime_t hrtick_time; 1267 #endif 1268 1269 #ifdef CONFIG_SCHEDSTATS 1270 /* latency stats */ 1271 struct sched_info rq_sched_info; 1272 unsigned long long rq_cpu_time; 1273 1274 /* sys_sched_yield() stats */ 1275 unsigned int yld_count; 1276 1277 /* schedule() stats */ 1278 unsigned int sched_count; 1279 unsigned int sched_goidle; 1280 1281 /* try_to_wake_up() stats */ 1282 unsigned int ttwu_count; 1283 unsigned int ttwu_local; 1284 #endif 1285 1286 #ifdef CONFIG_CPU_IDLE 1287 /* Must be inspected within a RCU lock section */ 1288 struct cpuidle_state *idle_state; 1289 #endif 1290 1291 unsigned int nr_pinned; 1292 unsigned int push_busy; 1293 struct cpu_stop_work push_work; 1294 1295 #ifdef CONFIG_SCHED_CORE 1296 /* per rq */ 1297 struct rq *core; 1298 struct task_struct *core_pick; 1299 struct sched_dl_entity *core_dl_server; 1300 unsigned int core_enabled; 1301 unsigned int core_sched_seq; 1302 struct rb_root core_tree; 1303 1304 /* shared state -- careful with sched_core_cpu_deactivate() */ 1305 unsigned int core_task_seq; 1306 unsigned int core_pick_seq; 1307 unsigned long core_cookie; 1308 unsigned int core_forceidle_count; 1309 unsigned int core_forceidle_seq; 1310 unsigned int core_forceidle_occupation; 1311 u64 core_forceidle_start; 1312 #endif /* CONFIG_SCHED_CORE */ 1313 1314 /* Scratch cpumask to be temporarily used under rq_lock */ 1315 cpumask_var_t scratch_mask; 1316 1317 #ifdef CONFIG_CFS_BANDWIDTH 1318 call_single_data_t cfsb_csd; 1319 struct list_head cfsb_csd_list; 1320 #endif 1321 }; 1322 1323 #ifdef CONFIG_FAIR_GROUP_SCHED 1324 1325 /* CPU runqueue to which this cfs_rq is attached */ 1326 static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1327 { 1328 return cfs_rq->rq; 1329 } 1330 1331 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 1332 1333 static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1334 { 1335 return container_of(cfs_rq, struct rq, cfs); 1336 } 1337 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 1338 1339 static inline int cpu_of(struct rq *rq) 1340 { 1341 return rq->cpu; 1342 } 1343 1344 #define MDF_PUSH 0x01 1345 1346 static inline bool is_migration_disabled(struct task_struct *p) 1347 { 1348 return p->migration_disabled; 1349 } 1350 1351 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); 1352 1353 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) 1354 #define this_rq() this_cpu_ptr(&runqueues) 1355 #define task_rq(p) cpu_rq(task_cpu(p)) 1356 #define cpu_curr(cpu) (cpu_rq(cpu)->curr) 1357 #define raw_rq() raw_cpu_ptr(&runqueues) 1358 1359 #ifdef CONFIG_SCHED_PROXY_EXEC 1360 static inline void rq_set_donor(struct rq *rq, struct task_struct *t) 1361 { 1362 rcu_assign_pointer(rq->donor, t); 1363 } 1364 #else 1365 static inline void rq_set_donor(struct rq *rq, struct task_struct *t) 1366 { 1367 /* Do nothing */ 1368 } 1369 #endif 1370 1371 #ifdef CONFIG_SCHED_CORE 1372 static inline struct cpumask *sched_group_span(struct sched_group *sg); 1373 1374 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled); 1375 1376 static inline bool sched_core_enabled(struct rq *rq) 1377 { 1378 return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled; 1379 } 1380 1381 static inline bool sched_core_disabled(void) 1382 { 1383 return !static_branch_unlikely(&__sched_core_enabled); 1384 } 1385 1386 /* 1387 * Be careful with this function; not for general use. The return value isn't 1388 * stable unless you actually hold a relevant rq->__lock. 1389 */ 1390 static inline raw_spinlock_t *rq_lockp(struct rq *rq) 1391 { 1392 if (sched_core_enabled(rq)) 1393 return &rq->core->__lock; 1394 1395 return &rq->__lock; 1396 } 1397 1398 static inline raw_spinlock_t *__rq_lockp(struct rq *rq) 1399 { 1400 if (rq->core_enabled) 1401 return &rq->core->__lock; 1402 1403 return &rq->__lock; 1404 } 1405 1406 extern bool 1407 cfs_prio_less(const struct task_struct *a, const struct task_struct *b, bool fi); 1408 1409 extern void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi); 1410 1411 /* 1412 * Helpers to check if the CPU's core cookie matches with the task's cookie 1413 * when core scheduling is enabled. 1414 * A special case is that the task's cookie always matches with CPU's core 1415 * cookie if the CPU is in an idle core. 1416 */ 1417 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p) 1418 { 1419 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1420 if (!sched_core_enabled(rq)) 1421 return true; 1422 1423 return rq->core->core_cookie == p->core_cookie; 1424 } 1425 1426 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) 1427 { 1428 bool idle_core = true; 1429 int cpu; 1430 1431 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1432 if (!sched_core_enabled(rq)) 1433 return true; 1434 1435 for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) { 1436 if (!available_idle_cpu(cpu)) { 1437 idle_core = false; 1438 break; 1439 } 1440 } 1441 1442 /* 1443 * A CPU in an idle core is always the best choice for tasks with 1444 * cookies. 1445 */ 1446 return idle_core || rq->core->core_cookie == p->core_cookie; 1447 } 1448 1449 static inline bool sched_group_cookie_match(struct rq *rq, 1450 struct task_struct *p, 1451 struct sched_group *group) 1452 { 1453 int cpu; 1454 1455 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1456 if (!sched_core_enabled(rq)) 1457 return true; 1458 1459 for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) { 1460 if (sched_core_cookie_match(cpu_rq(cpu), p)) 1461 return true; 1462 } 1463 return false; 1464 } 1465 1466 static inline bool sched_core_enqueued(struct task_struct *p) 1467 { 1468 return !RB_EMPTY_NODE(&p->core_node); 1469 } 1470 1471 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p); 1472 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags); 1473 1474 extern void sched_core_get(void); 1475 extern void sched_core_put(void); 1476 1477 #else /* !CONFIG_SCHED_CORE: */ 1478 1479 static inline bool sched_core_enabled(struct rq *rq) 1480 { 1481 return false; 1482 } 1483 1484 static inline bool sched_core_disabled(void) 1485 { 1486 return true; 1487 } 1488 1489 static inline raw_spinlock_t *rq_lockp(struct rq *rq) 1490 { 1491 return &rq->__lock; 1492 } 1493 1494 static inline raw_spinlock_t *__rq_lockp(struct rq *rq) 1495 { 1496 return &rq->__lock; 1497 } 1498 1499 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p) 1500 { 1501 return true; 1502 } 1503 1504 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) 1505 { 1506 return true; 1507 } 1508 1509 static inline bool sched_group_cookie_match(struct rq *rq, 1510 struct task_struct *p, 1511 struct sched_group *group) 1512 { 1513 return true; 1514 } 1515 1516 #endif /* !CONFIG_SCHED_CORE */ 1517 1518 #ifdef CONFIG_RT_GROUP_SCHED 1519 # ifdef CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED 1520 DECLARE_STATIC_KEY_FALSE(rt_group_sched); 1521 static inline bool rt_group_sched_enabled(void) 1522 { 1523 return static_branch_unlikely(&rt_group_sched); 1524 } 1525 # else /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED: */ 1526 DECLARE_STATIC_KEY_TRUE(rt_group_sched); 1527 static inline bool rt_group_sched_enabled(void) 1528 { 1529 return static_branch_likely(&rt_group_sched); 1530 } 1531 # endif /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED */ 1532 #else /* !CONFIG_RT_GROUP_SCHED: */ 1533 # define rt_group_sched_enabled() false 1534 #endif /* !CONFIG_RT_GROUP_SCHED */ 1535 1536 static inline void lockdep_assert_rq_held(struct rq *rq) 1537 { 1538 lockdep_assert_held(__rq_lockp(rq)); 1539 } 1540 1541 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass); 1542 extern bool raw_spin_rq_trylock(struct rq *rq); 1543 extern void raw_spin_rq_unlock(struct rq *rq); 1544 1545 static inline void raw_spin_rq_lock(struct rq *rq) 1546 { 1547 raw_spin_rq_lock_nested(rq, 0); 1548 } 1549 1550 static inline void raw_spin_rq_lock_irq(struct rq *rq) 1551 { 1552 local_irq_disable(); 1553 raw_spin_rq_lock(rq); 1554 } 1555 1556 static inline void raw_spin_rq_unlock_irq(struct rq *rq) 1557 { 1558 raw_spin_rq_unlock(rq); 1559 local_irq_enable(); 1560 } 1561 1562 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq) 1563 { 1564 unsigned long flags; 1565 1566 local_irq_save(flags); 1567 raw_spin_rq_lock(rq); 1568 1569 return flags; 1570 } 1571 1572 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags) 1573 { 1574 raw_spin_rq_unlock(rq); 1575 local_irq_restore(flags); 1576 } 1577 1578 #define raw_spin_rq_lock_irqsave(rq, flags) \ 1579 do { \ 1580 flags = _raw_spin_rq_lock_irqsave(rq); \ 1581 } while (0) 1582 1583 #ifdef CONFIG_SCHED_SMT 1584 extern void __update_idle_core(struct rq *rq); 1585 1586 static inline void update_idle_core(struct rq *rq) 1587 { 1588 if (static_branch_unlikely(&sched_smt_present)) 1589 __update_idle_core(rq); 1590 } 1591 1592 #else /* !CONFIG_SCHED_SMT: */ 1593 static inline void update_idle_core(struct rq *rq) { } 1594 #endif /* !CONFIG_SCHED_SMT */ 1595 1596 #ifdef CONFIG_FAIR_GROUP_SCHED 1597 1598 static inline struct task_struct *task_of(struct sched_entity *se) 1599 { 1600 WARN_ON_ONCE(!entity_is_task(se)); 1601 return container_of(se, struct task_struct, se); 1602 } 1603 1604 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p) 1605 { 1606 return p->se.cfs_rq; 1607 } 1608 1609 /* runqueue on which this entity is (to be) queued */ 1610 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se) 1611 { 1612 return se->cfs_rq; 1613 } 1614 1615 /* runqueue "owned" by this group */ 1616 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) 1617 { 1618 return grp->my_q; 1619 } 1620 1621 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 1622 1623 #define task_of(_se) container_of(_se, struct task_struct, se) 1624 1625 static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p) 1626 { 1627 return &task_rq(p)->cfs; 1628 } 1629 1630 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se) 1631 { 1632 const struct task_struct *p = task_of(se); 1633 struct rq *rq = task_rq(p); 1634 1635 return &rq->cfs; 1636 } 1637 1638 /* runqueue "owned" by this group */ 1639 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) 1640 { 1641 return NULL; 1642 } 1643 1644 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 1645 1646 extern void update_rq_clock(struct rq *rq); 1647 1648 /* 1649 * rq::clock_update_flags bits 1650 * 1651 * %RQCF_REQ_SKIP - will request skipping of clock update on the next 1652 * call to __schedule(). This is an optimisation to avoid 1653 * neighbouring rq clock updates. 1654 * 1655 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is 1656 * in effect and calls to update_rq_clock() are being ignored. 1657 * 1658 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been 1659 * made to update_rq_clock() since the last time rq::lock was pinned. 1660 * 1661 * If inside of __schedule(), clock_update_flags will have been 1662 * shifted left (a left shift is a cheap operation for the fast path 1663 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use, 1664 * 1665 * if (rq-clock_update_flags >= RQCF_UPDATED) 1666 * 1667 * to check if %RQCF_UPDATED is set. It'll never be shifted more than 1668 * one position though, because the next rq_unpin_lock() will shift it 1669 * back. 1670 */ 1671 #define RQCF_REQ_SKIP 0x01 1672 #define RQCF_ACT_SKIP 0x02 1673 #define RQCF_UPDATED 0x04 1674 1675 static inline void assert_clock_updated(struct rq *rq) 1676 { 1677 /* 1678 * The only reason for not seeing a clock update since the 1679 * last rq_pin_lock() is if we're currently skipping updates. 1680 */ 1681 WARN_ON_ONCE(rq->clock_update_flags < RQCF_ACT_SKIP); 1682 } 1683 1684 static inline u64 rq_clock(struct rq *rq) 1685 { 1686 lockdep_assert_rq_held(rq); 1687 assert_clock_updated(rq); 1688 1689 return rq->clock; 1690 } 1691 1692 static inline u64 rq_clock_task(struct rq *rq) 1693 { 1694 lockdep_assert_rq_held(rq); 1695 assert_clock_updated(rq); 1696 1697 return rq->clock_task; 1698 } 1699 1700 static inline void rq_clock_skip_update(struct rq *rq) 1701 { 1702 lockdep_assert_rq_held(rq); 1703 rq->clock_update_flags |= RQCF_REQ_SKIP; 1704 } 1705 1706 /* 1707 * See rt task throttling, which is the only time a skip 1708 * request is canceled. 1709 */ 1710 static inline void rq_clock_cancel_skipupdate(struct rq *rq) 1711 { 1712 lockdep_assert_rq_held(rq); 1713 rq->clock_update_flags &= ~RQCF_REQ_SKIP; 1714 } 1715 1716 /* 1717 * During cpu offlining and rq wide unthrottling, we can trigger 1718 * an update_rq_clock() for several cfs and rt runqueues (Typically 1719 * when using list_for_each_entry_*) 1720 * rq_clock_start_loop_update() can be called after updating the clock 1721 * once and before iterating over the list to prevent multiple update. 1722 * After the iterative traversal, we need to call rq_clock_stop_loop_update() 1723 * to clear RQCF_ACT_SKIP of rq->clock_update_flags. 1724 */ 1725 static inline void rq_clock_start_loop_update(struct rq *rq) 1726 { 1727 lockdep_assert_rq_held(rq); 1728 WARN_ON_ONCE(rq->clock_update_flags & RQCF_ACT_SKIP); 1729 rq->clock_update_flags |= RQCF_ACT_SKIP; 1730 } 1731 1732 static inline void rq_clock_stop_loop_update(struct rq *rq) 1733 { 1734 lockdep_assert_rq_held(rq); 1735 rq->clock_update_flags &= ~RQCF_ACT_SKIP; 1736 } 1737 1738 struct rq_flags { 1739 unsigned long flags; 1740 struct pin_cookie cookie; 1741 /* 1742 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the 1743 * current pin context is stashed here in case it needs to be 1744 * restored in rq_repin_lock(). 1745 */ 1746 unsigned int clock_update_flags; 1747 }; 1748 1749 extern struct balance_callback balance_push_callback; 1750 1751 #ifdef CONFIG_SCHED_CLASS_EXT 1752 extern const struct sched_class ext_sched_class; 1753 1754 DECLARE_STATIC_KEY_FALSE(__scx_enabled); /* SCX BPF scheduler loaded */ 1755 DECLARE_STATIC_KEY_FALSE(__scx_switched_all); /* all fair class tasks on SCX */ 1756 1757 #define scx_enabled() static_branch_unlikely(&__scx_enabled) 1758 #define scx_switched_all() static_branch_unlikely(&__scx_switched_all) 1759 1760 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) 1761 { 1762 if (!scx_enabled()) 1763 return; 1764 WRITE_ONCE(rq->scx.clock, clock); 1765 smp_store_release(&rq->scx.flags, rq->scx.flags | SCX_RQ_CLK_VALID); 1766 } 1767 1768 static inline void scx_rq_clock_invalidate(struct rq *rq) 1769 { 1770 if (!scx_enabled()) 1771 return; 1772 WRITE_ONCE(rq->scx.flags, rq->scx.flags & ~SCX_RQ_CLK_VALID); 1773 } 1774 1775 #else /* !CONFIG_SCHED_CLASS_EXT: */ 1776 #define scx_enabled() false 1777 #define scx_switched_all() false 1778 1779 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) {} 1780 static inline void scx_rq_clock_invalidate(struct rq *rq) {} 1781 #endif /* !CONFIG_SCHED_CLASS_EXT */ 1782 1783 /* 1784 * Lockdep annotation that avoids accidental unlocks; it's like a 1785 * sticky/continuous lockdep_assert_held(). 1786 * 1787 * This avoids code that has access to 'struct rq *rq' (basically everything in 1788 * the scheduler) from accidentally unlocking the rq if they do not also have a 1789 * copy of the (on-stack) 'struct rq_flags rf'. 1790 * 1791 * Also see Documentation/locking/lockdep-design.rst. 1792 */ 1793 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf) 1794 { 1795 rf->cookie = lockdep_pin_lock(__rq_lockp(rq)); 1796 1797 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 1798 rf->clock_update_flags = 0; 1799 WARN_ON_ONCE(rq->balance_callback && rq->balance_callback != &balance_push_callback); 1800 } 1801 1802 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf) 1803 { 1804 if (rq->clock_update_flags > RQCF_ACT_SKIP) 1805 rf->clock_update_flags = RQCF_UPDATED; 1806 1807 scx_rq_clock_invalidate(rq); 1808 lockdep_unpin_lock(__rq_lockp(rq), rf->cookie); 1809 } 1810 1811 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf) 1812 { 1813 lockdep_repin_lock(__rq_lockp(rq), rf->cookie); 1814 1815 /* 1816 * Restore the value we stashed in @rf for this pin context. 1817 */ 1818 rq->clock_update_flags |= rf->clock_update_flags; 1819 } 1820 1821 extern 1822 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1823 __acquires(rq->lock); 1824 1825 extern 1826 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1827 __acquires(p->pi_lock) 1828 __acquires(rq->lock); 1829 1830 static inline void 1831 __task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) 1832 __releases(rq->lock) 1833 { 1834 rq_unpin_lock(rq, rf); 1835 raw_spin_rq_unlock(rq); 1836 } 1837 1838 static inline void 1839 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) 1840 __releases(rq->lock) 1841 __releases(p->pi_lock) 1842 { 1843 __task_rq_unlock(rq, p, rf); 1844 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); 1845 } 1846 1847 DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct, 1848 _T->rq = task_rq_lock(_T->lock, &_T->rf), 1849 task_rq_unlock(_T->rq, _T->lock, &_T->rf), 1850 struct rq *rq; struct rq_flags rf) 1851 1852 DEFINE_LOCK_GUARD_1(__task_rq_lock, struct task_struct, 1853 _T->rq = __task_rq_lock(_T->lock, &_T->rf), 1854 __task_rq_unlock(_T->rq, _T->lock, &_T->rf), 1855 struct rq *rq; struct rq_flags rf) 1856 1857 static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) 1858 __acquires(rq->lock) 1859 { 1860 raw_spin_rq_lock_irqsave(rq, rf->flags); 1861 rq_pin_lock(rq, rf); 1862 } 1863 1864 static inline void rq_lock_irq(struct rq *rq, struct rq_flags *rf) 1865 __acquires(rq->lock) 1866 { 1867 raw_spin_rq_lock_irq(rq); 1868 rq_pin_lock(rq, rf); 1869 } 1870 1871 static inline void rq_lock(struct rq *rq, struct rq_flags *rf) 1872 __acquires(rq->lock) 1873 { 1874 raw_spin_rq_lock(rq); 1875 rq_pin_lock(rq, rf); 1876 } 1877 1878 static inline void rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf) 1879 __releases(rq->lock) 1880 { 1881 rq_unpin_lock(rq, rf); 1882 raw_spin_rq_unlock_irqrestore(rq, rf->flags); 1883 } 1884 1885 static inline void rq_unlock_irq(struct rq *rq, struct rq_flags *rf) 1886 __releases(rq->lock) 1887 { 1888 rq_unpin_lock(rq, rf); 1889 raw_spin_rq_unlock_irq(rq); 1890 } 1891 1892 static inline void rq_unlock(struct rq *rq, struct rq_flags *rf) 1893 __releases(rq->lock) 1894 { 1895 rq_unpin_lock(rq, rf); 1896 raw_spin_rq_unlock(rq); 1897 } 1898 1899 DEFINE_LOCK_GUARD_1(rq_lock, struct rq, 1900 rq_lock(_T->lock, &_T->rf), 1901 rq_unlock(_T->lock, &_T->rf), 1902 struct rq_flags rf) 1903 1904 DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq, 1905 rq_lock_irq(_T->lock, &_T->rf), 1906 rq_unlock_irq(_T->lock, &_T->rf), 1907 struct rq_flags rf) 1908 1909 DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq, 1910 rq_lock_irqsave(_T->lock, &_T->rf), 1911 rq_unlock_irqrestore(_T->lock, &_T->rf), 1912 struct rq_flags rf) 1913 1914 static inline struct rq *this_rq_lock_irq(struct rq_flags *rf) 1915 __acquires(rq->lock) 1916 { 1917 struct rq *rq; 1918 1919 local_irq_disable(); 1920 rq = this_rq(); 1921 rq_lock(rq, rf); 1922 1923 return rq; 1924 } 1925 1926 #ifdef CONFIG_NUMA 1927 1928 enum numa_topology_type { 1929 NUMA_DIRECT, 1930 NUMA_GLUELESS_MESH, 1931 NUMA_BACKPLANE, 1932 }; 1933 1934 extern enum numa_topology_type sched_numa_topology_type; 1935 extern int sched_max_numa_distance; 1936 extern bool find_numa_distance(int distance); 1937 extern void sched_init_numa(int offline_node); 1938 extern void sched_update_numa(int cpu, bool online); 1939 extern void sched_domains_numa_masks_set(unsigned int cpu); 1940 extern void sched_domains_numa_masks_clear(unsigned int cpu); 1941 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu); 1942 1943 #else /* !CONFIG_NUMA: */ 1944 1945 static inline void sched_init_numa(int offline_node) { } 1946 static inline void sched_update_numa(int cpu, bool online) { } 1947 static inline void sched_domains_numa_masks_set(unsigned int cpu) { } 1948 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { } 1949 1950 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu) 1951 { 1952 return nr_cpu_ids; 1953 } 1954 1955 #endif /* !CONFIG_NUMA */ 1956 1957 #ifdef CONFIG_NUMA_BALANCING 1958 1959 /* The regions in numa_faults array from task_struct */ 1960 enum numa_faults_stats { 1961 NUMA_MEM = 0, 1962 NUMA_CPU, 1963 NUMA_MEMBUF, 1964 NUMA_CPUBUF 1965 }; 1966 1967 extern void sched_setnuma(struct task_struct *p, int node); 1968 extern int migrate_task_to(struct task_struct *p, int cpu); 1969 extern int migrate_swap(struct task_struct *p, struct task_struct *t, 1970 int cpu, int scpu); 1971 extern void init_numa_balancing(u64 clone_flags, struct task_struct *p); 1972 1973 #else /* !CONFIG_NUMA_BALANCING: */ 1974 1975 static inline void 1976 init_numa_balancing(u64 clone_flags, struct task_struct *p) 1977 { 1978 } 1979 1980 #endif /* !CONFIG_NUMA_BALANCING */ 1981 1982 static inline void 1983 queue_balance_callback(struct rq *rq, 1984 struct balance_callback *head, 1985 void (*func)(struct rq *rq)) 1986 { 1987 lockdep_assert_rq_held(rq); 1988 1989 /* 1990 * Don't (re)queue an already queued item; nor queue anything when 1991 * balance_push() is active, see the comment with 1992 * balance_push_callback. 1993 */ 1994 if (unlikely(head->next || rq->balance_callback == &balance_push_callback)) 1995 return; 1996 1997 head->func = func; 1998 head->next = rq->balance_callback; 1999 rq->balance_callback = head; 2000 } 2001 2002 #define rcu_dereference_check_sched_domain(p) \ 2003 rcu_dereference_check((p), lockdep_is_held(&sched_domains_mutex)) 2004 2005 /* 2006 * The domain tree (rq->sd) is protected by RCU's quiescent state transition. 2007 * See destroy_sched_domains: call_rcu for details. 2008 * 2009 * The domain tree of any CPU may only be accessed from within 2010 * preempt-disabled sections. 2011 */ 2012 #define for_each_domain(cpu, __sd) \ 2013 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \ 2014 __sd; __sd = __sd->parent) 2015 2016 /* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */ 2017 #define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) | 2018 static const unsigned int SD_SHARED_CHILD_MASK = 2019 #include <linux/sched/sd_flags.h> 2020 0; 2021 #undef SD_FLAG 2022 2023 /** 2024 * highest_flag_domain - Return highest sched_domain containing flag. 2025 * @cpu: The CPU whose highest level of sched domain is to 2026 * be returned. 2027 * @flag: The flag to check for the highest sched_domain 2028 * for the given CPU. 2029 * 2030 * Returns the highest sched_domain of a CPU which contains @flag. If @flag has 2031 * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag. 2032 */ 2033 static inline struct sched_domain *highest_flag_domain(int cpu, int flag) 2034 { 2035 struct sched_domain *sd, *hsd = NULL; 2036 2037 for_each_domain(cpu, sd) { 2038 if (sd->flags & flag) { 2039 hsd = sd; 2040 continue; 2041 } 2042 2043 /* 2044 * Stop the search if @flag is known to be shared at lower 2045 * levels. It will not be found further up. 2046 */ 2047 if (flag & SD_SHARED_CHILD_MASK) 2048 break; 2049 } 2050 2051 return hsd; 2052 } 2053 2054 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) 2055 { 2056 struct sched_domain *sd; 2057 2058 for_each_domain(cpu, sd) { 2059 if (sd->flags & flag) 2060 break; 2061 } 2062 2063 return sd; 2064 } 2065 2066 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc); 2067 DECLARE_PER_CPU(int, sd_llc_size); 2068 DECLARE_PER_CPU(int, sd_llc_id); 2069 DECLARE_PER_CPU(int, sd_share_id); 2070 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared); 2071 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa); 2072 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing); 2073 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity); 2074 2075 extern struct static_key_false sched_asym_cpucapacity; 2076 extern struct static_key_false sched_cluster_active; 2077 2078 static __always_inline bool sched_asym_cpucap_active(void) 2079 { 2080 return static_branch_unlikely(&sched_asym_cpucapacity); 2081 } 2082 2083 struct sched_group_capacity { 2084 atomic_t ref; 2085 /* 2086 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity 2087 * for a single CPU. 2088 */ 2089 unsigned long capacity; 2090 unsigned long min_capacity; /* Min per-CPU capacity in group */ 2091 unsigned long max_capacity; /* Max per-CPU capacity in group */ 2092 unsigned long next_update; 2093 int imbalance; /* XXX unrelated to capacity but shared group state */ 2094 2095 int id; 2096 2097 unsigned long cpumask[]; /* Balance mask */ 2098 }; 2099 2100 struct sched_group { 2101 struct sched_group *next; /* Must be a circular list */ 2102 atomic_t ref; 2103 2104 unsigned int group_weight; 2105 unsigned int cores; 2106 struct sched_group_capacity *sgc; 2107 int asym_prefer_cpu; /* CPU of highest priority in group */ 2108 int flags; 2109 2110 /* 2111 * The CPUs this group covers. 2112 * 2113 * NOTE: this field is variable length. (Allocated dynamically 2114 * by attaching extra space to the end of the structure, 2115 * depending on how many CPUs the kernel has booted up with) 2116 */ 2117 unsigned long cpumask[]; 2118 }; 2119 2120 static inline struct cpumask *sched_group_span(struct sched_group *sg) 2121 { 2122 return to_cpumask(sg->cpumask); 2123 } 2124 2125 /* 2126 * See build_balance_mask(). 2127 */ 2128 static inline struct cpumask *group_balance_mask(struct sched_group *sg) 2129 { 2130 return to_cpumask(sg->sgc->cpumask); 2131 } 2132 2133 extern int group_balance_cpu(struct sched_group *sg); 2134 2135 extern void update_sched_domain_debugfs(void); 2136 extern void dirty_sched_domain_sysctl(int cpu); 2137 2138 extern int sched_update_scaling(void); 2139 2140 static inline const struct cpumask *task_user_cpus(struct task_struct *p) 2141 { 2142 if (!p->user_cpus_ptr) 2143 return cpu_possible_mask; /* &init_task.cpus_mask */ 2144 return p->user_cpus_ptr; 2145 } 2146 2147 #ifdef CONFIG_CGROUP_SCHED 2148 2149 /* 2150 * Return the group to which this tasks belongs. 2151 * 2152 * We cannot use task_css() and friends because the cgroup subsystem 2153 * changes that value before the cgroup_subsys::attach() method is called, 2154 * therefore we cannot pin it and might observe the wrong value. 2155 * 2156 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup 2157 * core changes this before calling sched_move_task(). 2158 * 2159 * Instead we use a 'copy' which is updated from sched_move_task() while 2160 * holding both task_struct::pi_lock and rq::lock. 2161 */ 2162 static inline struct task_group *task_group(struct task_struct *p) 2163 { 2164 return p->sched_task_group; 2165 } 2166 2167 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ 2168 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) 2169 { 2170 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED) 2171 struct task_group *tg = task_group(p); 2172 #endif 2173 2174 #ifdef CONFIG_FAIR_GROUP_SCHED 2175 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]); 2176 p->se.cfs_rq = tg->cfs_rq[cpu]; 2177 p->se.parent = tg->se[cpu]; 2178 p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0; 2179 #endif 2180 2181 #ifdef CONFIG_RT_GROUP_SCHED 2182 /* 2183 * p->rt.rt_rq is NULL initially and it is easier to assign 2184 * root_task_group's rt_rq than switching in rt_rq_of_se() 2185 * Clobbers tg(!) 2186 */ 2187 if (!rt_group_sched_enabled()) 2188 tg = &root_task_group; 2189 p->rt.rt_rq = tg->rt_rq[cpu]; 2190 p->rt.parent = tg->rt_se[cpu]; 2191 #endif /* CONFIG_RT_GROUP_SCHED */ 2192 } 2193 2194 #else /* !CONFIG_CGROUP_SCHED: */ 2195 2196 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } 2197 2198 static inline struct task_group *task_group(struct task_struct *p) 2199 { 2200 return NULL; 2201 } 2202 2203 #endif /* !CONFIG_CGROUP_SCHED */ 2204 2205 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) 2206 { 2207 set_task_rq(p, cpu); 2208 #ifdef CONFIG_SMP 2209 /* 2210 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be 2211 * successfully executed on another CPU. We must ensure that updates of 2212 * per-task data have been completed by this moment. 2213 */ 2214 smp_wmb(); 2215 WRITE_ONCE(task_thread_info(p)->cpu, cpu); 2216 p->wake_cpu = cpu; 2217 #endif /* CONFIG_SMP */ 2218 } 2219 2220 /* 2221 * Tunables: 2222 */ 2223 2224 #define SCHED_FEAT(name, enabled) \ 2225 __SCHED_FEAT_##name , 2226 2227 enum { 2228 #include "features.h" 2229 __SCHED_FEAT_NR, 2230 }; 2231 2232 #undef SCHED_FEAT 2233 2234 /* 2235 * To support run-time toggling of sched features, all the translation units 2236 * (but core.c) reference the sysctl_sched_features defined in core.c. 2237 */ 2238 extern __read_mostly unsigned int sysctl_sched_features; 2239 2240 #ifdef CONFIG_JUMP_LABEL 2241 2242 #define SCHED_FEAT(name, enabled) \ 2243 static __always_inline bool static_branch_##name(struct static_key *key) \ 2244 { \ 2245 return static_key_##enabled(key); \ 2246 } 2247 2248 #include "features.h" 2249 #undef SCHED_FEAT 2250 2251 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR]; 2252 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x])) 2253 2254 #else /* !CONFIG_JUMP_LABEL: */ 2255 2256 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) 2257 2258 #endif /* !CONFIG_JUMP_LABEL */ 2259 2260 extern struct static_key_false sched_numa_balancing; 2261 extern struct static_key_false sched_schedstats; 2262 2263 static inline u64 global_rt_period(void) 2264 { 2265 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC; 2266 } 2267 2268 static inline u64 global_rt_runtime(void) 2269 { 2270 if (sysctl_sched_rt_runtime < 0) 2271 return RUNTIME_INF; 2272 2273 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC; 2274 } 2275 2276 /* 2277 * Is p the current execution context? 2278 */ 2279 static inline int task_current(struct rq *rq, struct task_struct *p) 2280 { 2281 return rq->curr == p; 2282 } 2283 2284 /* 2285 * Is p the current scheduling context? 2286 * 2287 * Note that it might be the current execution context at the same time if 2288 * rq->curr == rq->donor == p. 2289 */ 2290 static inline int task_current_donor(struct rq *rq, struct task_struct *p) 2291 { 2292 return rq->donor == p; 2293 } 2294 2295 static inline bool task_is_blocked(struct task_struct *p) 2296 { 2297 if (!sched_proxy_exec()) 2298 return false; 2299 2300 return !!p->blocked_on; 2301 } 2302 2303 static inline int task_on_cpu(struct rq *rq, struct task_struct *p) 2304 { 2305 return p->on_cpu; 2306 } 2307 2308 static inline int task_on_rq_queued(struct task_struct *p) 2309 { 2310 return READ_ONCE(p->on_rq) == TASK_ON_RQ_QUEUED; 2311 } 2312 2313 static inline int task_on_rq_migrating(struct task_struct *p) 2314 { 2315 return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING; 2316 } 2317 2318 /* Wake flags. The first three directly map to some SD flag value */ 2319 #define WF_EXEC 0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */ 2320 #define WF_FORK 0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */ 2321 #define WF_TTWU 0x08 /* Wakeup; maps to SD_BALANCE_WAKE */ 2322 2323 #define WF_SYNC 0x10 /* Waker goes to sleep after wakeup */ 2324 #define WF_MIGRATED 0x20 /* Internal use, task got migrated */ 2325 #define WF_CURRENT_CPU 0x40 /* Prefer to move the wakee to the current CPU. */ 2326 #define WF_RQ_SELECTED 0x80 /* ->select_task_rq() was called */ 2327 2328 static_assert(WF_EXEC == SD_BALANCE_EXEC); 2329 static_assert(WF_FORK == SD_BALANCE_FORK); 2330 static_assert(WF_TTWU == SD_BALANCE_WAKE); 2331 2332 /* 2333 * To aid in avoiding the subversion of "niceness" due to uneven distribution 2334 * of tasks with abnormal "nice" values across CPUs the contribution that 2335 * each task makes to its run queue's load is weighted according to its 2336 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a 2337 * scaled version of the new time slice allocation that they receive on time 2338 * slice expiry etc. 2339 */ 2340 2341 #define WEIGHT_IDLEPRIO 3 2342 #define WMULT_IDLEPRIO 1431655765 2343 2344 extern const int sched_prio_to_weight[40]; 2345 extern const u32 sched_prio_to_wmult[40]; 2346 2347 /* 2348 * {de,en}queue flags: 2349 * 2350 * SLEEP/WAKEUP - task is no-longer/just-became runnable 2351 * 2352 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks 2353 * are in a known state which allows modification. Such pairs 2354 * should preserve as much state as possible. 2355 * 2356 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location 2357 * in the runqueue. 2358 * 2359 * NOCLOCK - skip the update_rq_clock() (avoids double updates) 2360 * 2361 * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE) 2362 * 2363 * DELAYED - de/re-queue a sched_delayed task 2364 * 2365 * CLASS - going to update p->sched_class; makes sched_change call the 2366 * various switch methods. 2367 * 2368 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified) 2369 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline) 2370 * ENQUEUE_MIGRATED - the task was migrated during wakeup 2371 * ENQUEUE_RQ_SELECTED - ->select_task_rq() was called 2372 * 2373 * XXX SAVE/RESTORE in combination with CLASS doesn't really make sense, but 2374 * SCHED_DEADLINE seems to rely on this for now. 2375 */ 2376 2377 #define DEQUEUE_SLEEP 0x0001 /* Matches ENQUEUE_WAKEUP */ 2378 #define DEQUEUE_SAVE 0x0002 /* Matches ENQUEUE_RESTORE */ 2379 #define DEQUEUE_MOVE 0x0004 /* Matches ENQUEUE_MOVE */ 2380 #define DEQUEUE_NOCLOCK 0x0008 /* Matches ENQUEUE_NOCLOCK */ 2381 2382 #define DEQUEUE_MIGRATING 0x0010 /* Matches ENQUEUE_MIGRATING */ 2383 #define DEQUEUE_DELAYED 0x0020 /* Matches ENQUEUE_DELAYED */ 2384 #define DEQUEUE_CLASS 0x0040 /* Matches ENQUEUE_CLASS */ 2385 2386 #define DEQUEUE_SPECIAL 0x00010000 2387 #define DEQUEUE_THROTTLE 0x00020000 2388 2389 #define ENQUEUE_WAKEUP 0x0001 2390 #define ENQUEUE_RESTORE 0x0002 2391 #define ENQUEUE_MOVE 0x0004 2392 #define ENQUEUE_NOCLOCK 0x0008 2393 2394 #define ENQUEUE_MIGRATING 0x0010 2395 #define ENQUEUE_DELAYED 0x0020 2396 #define ENQUEUE_CLASS 0x0040 2397 2398 #define ENQUEUE_HEAD 0x00010000 2399 #define ENQUEUE_REPLENISH 0x00020000 2400 #define ENQUEUE_MIGRATED 0x00040000 2401 #define ENQUEUE_INITIAL 0x00080000 2402 #define ENQUEUE_RQ_SELECTED 0x00100000 2403 2404 #define RETRY_TASK ((void *)-1UL) 2405 2406 struct affinity_context { 2407 const struct cpumask *new_mask; 2408 struct cpumask *user_mask; 2409 unsigned int flags; 2410 }; 2411 2412 extern s64 update_curr_common(struct rq *rq); 2413 2414 struct sched_class { 2415 2416 #ifdef CONFIG_UCLAMP_TASK 2417 int uclamp_enabled; 2418 #endif 2419 /* 2420 * idle: 0 2421 * ext: 1 2422 * fair: 2 2423 * rt: 4 2424 * dl: 8 2425 * stop: 16 2426 */ 2427 unsigned int queue_mask; 2428 2429 /* 2430 * move_queued_task/activate_task/enqueue_task: rq->lock 2431 * ttwu_do_activate/activate_task/enqueue_task: rq->lock 2432 * wake_up_new_task/activate_task/enqueue_task: task_rq_lock 2433 * ttwu_runnable/enqueue_task: task_rq_lock 2434 * proxy_task_current: rq->lock 2435 * sched_change_end 2436 */ 2437 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags); 2438 /* 2439 * move_queued_task/deactivate_task/dequeue_task: rq->lock 2440 * __schedule/block_task/dequeue_task: rq->lock 2441 * proxy_task_current: rq->lock 2442 * wait_task_inactive: task_rq_lock 2443 * sched_change_begin 2444 */ 2445 bool (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags); 2446 2447 /* 2448 * do_sched_yield: rq->lock 2449 */ 2450 void (*yield_task) (struct rq *rq); 2451 /* 2452 * yield_to: rq->lock (double) 2453 */ 2454 bool (*yield_to_task)(struct rq *rq, struct task_struct *p); 2455 2456 /* 2457 * move_queued_task: rq->lock 2458 * __migrate_swap_task: rq->lock 2459 * ttwu_do_activate: rq->lock 2460 * ttwu_runnable: task_rq_lock 2461 * wake_up_new_task: task_rq_lock 2462 */ 2463 void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags); 2464 2465 /* 2466 * schedule/pick_next_task/prev_balance: rq->lock 2467 */ 2468 int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf); 2469 2470 /* 2471 * schedule/pick_next_task: rq->lock 2472 */ 2473 struct task_struct *(*pick_task)(struct rq *rq, struct rq_flags *rf); 2474 /* 2475 * Optional! When implemented pick_next_task() should be equivalent to: 2476 * 2477 * next = pick_task(); 2478 * if (next) { 2479 * put_prev_task(prev); 2480 * set_next_task_first(next); 2481 * } 2482 */ 2483 struct task_struct *(*pick_next_task)(struct rq *rq, struct task_struct *prev, 2484 struct rq_flags *rf); 2485 2486 /* 2487 * sched_change: 2488 * __schedule: rq->lock 2489 */ 2490 void (*put_prev_task)(struct rq *rq, struct task_struct *p, struct task_struct *next); 2491 void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first); 2492 2493 /* 2494 * select_task_rq: p->pi_lock 2495 * sched_exec: p->pi_lock 2496 */ 2497 int (*select_task_rq)(struct task_struct *p, int task_cpu, int flags); 2498 2499 /* 2500 * set_task_cpu: p->pi_lock || rq->lock (ttwu like) 2501 */ 2502 void (*migrate_task_rq)(struct task_struct *p, int new_cpu); 2503 2504 /* 2505 * ttwu_do_activate: rq->lock 2506 * wake_up_new_task: task_rq_lock 2507 */ 2508 void (*task_woken)(struct rq *this_rq, struct task_struct *task); 2509 2510 /* 2511 * do_set_cpus_allowed: task_rq_lock + sched_change 2512 */ 2513 void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx); 2514 2515 /* 2516 * sched_set_rq_{on,off}line: rq->lock 2517 */ 2518 void (*rq_online)(struct rq *rq); 2519 void (*rq_offline)(struct rq *rq); 2520 2521 /* 2522 * push_cpu_stop: p->pi_lock && rq->lock 2523 */ 2524 struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq); 2525 2526 /* 2527 * hrtick: rq->lock 2528 * sched_tick: rq->lock 2529 * sched_tick_remote: rq->lock 2530 */ 2531 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued); 2532 /* 2533 * sched_cgroup_fork: p->pi_lock 2534 */ 2535 void (*task_fork)(struct task_struct *p); 2536 /* 2537 * finish_task_switch: no locks 2538 */ 2539 void (*task_dead)(struct task_struct *p); 2540 2541 /* 2542 * sched_change 2543 */ 2544 void (*switching_from)(struct rq *this_rq, struct task_struct *task); 2545 void (*switched_from) (struct rq *this_rq, struct task_struct *task); 2546 void (*switching_to) (struct rq *this_rq, struct task_struct *task); 2547 void (*switched_to) (struct rq *this_rq, struct task_struct *task); 2548 u64 (*get_prio) (struct rq *this_rq, struct task_struct *task); 2549 void (*prio_changed) (struct rq *this_rq, struct task_struct *task, 2550 u64 oldprio); 2551 2552 /* 2553 * set_load_weight: task_rq_lock + sched_change 2554 * __setscheduler_parms: task_rq_lock + sched_change 2555 */ 2556 void (*reweight_task)(struct rq *this_rq, struct task_struct *task, 2557 const struct load_weight *lw); 2558 2559 /* 2560 * sched_rr_get_interval: task_rq_lock 2561 */ 2562 unsigned int (*get_rr_interval)(struct rq *rq, 2563 struct task_struct *task); 2564 2565 /* 2566 * task_sched_runtime: task_rq_lock 2567 */ 2568 void (*update_curr)(struct rq *rq); 2569 2570 #ifdef CONFIG_FAIR_GROUP_SCHED 2571 /* 2572 * sched_change_group: task_rq_lock + sched_change 2573 */ 2574 void (*task_change_group)(struct task_struct *p); 2575 #endif 2576 2577 #ifdef CONFIG_SCHED_CORE 2578 /* 2579 * pick_next_task: rq->lock 2580 * try_steal_cookie: rq->lock (double) 2581 */ 2582 int (*task_is_throttled)(struct task_struct *p, int cpu); 2583 #endif 2584 }; 2585 2586 /* 2587 * Does not nest; only used around sched_class::pick_task() rq-lock-breaks. 2588 */ 2589 static inline void rq_modified_clear(struct rq *rq) 2590 { 2591 rq->queue_mask = 0; 2592 } 2593 2594 static inline bool rq_modified_above(struct rq *rq, const struct sched_class * class) 2595 { 2596 unsigned int mask = class->queue_mask; 2597 return rq->queue_mask & ~((mask << 1) - 1); 2598 } 2599 2600 static inline void put_prev_task(struct rq *rq, struct task_struct *prev) 2601 { 2602 WARN_ON_ONCE(rq->donor != prev); 2603 prev->sched_class->put_prev_task(rq, prev, NULL); 2604 } 2605 2606 static inline void set_next_task(struct rq *rq, struct task_struct *next) 2607 { 2608 next->sched_class->set_next_task(rq, next, false); 2609 } 2610 2611 static inline void 2612 __put_prev_set_next_dl_server(struct rq *rq, 2613 struct task_struct *prev, 2614 struct task_struct *next) 2615 { 2616 prev->dl_server = NULL; 2617 next->dl_server = rq->dl_server; 2618 rq->dl_server = NULL; 2619 } 2620 2621 static inline void put_prev_set_next_task(struct rq *rq, 2622 struct task_struct *prev, 2623 struct task_struct *next) 2624 { 2625 WARN_ON_ONCE(rq->donor != prev); 2626 2627 __put_prev_set_next_dl_server(rq, prev, next); 2628 2629 if (next == prev) 2630 return; 2631 2632 prev->sched_class->put_prev_task(rq, prev, next); 2633 next->sched_class->set_next_task(rq, next, true); 2634 } 2635 2636 /* 2637 * Helper to define a sched_class instance; each one is placed in a separate 2638 * section which is ordered by the linker script: 2639 * 2640 * include/asm-generic/vmlinux.lds.h 2641 * 2642 * *CAREFUL* they are laid out in *REVERSE* order!!! 2643 * 2644 * Also enforce alignment on the instance, not the type, to guarantee layout. 2645 */ 2646 #define DEFINE_SCHED_CLASS(name) \ 2647 const struct sched_class name##_sched_class \ 2648 __aligned(__alignof__(struct sched_class)) \ 2649 __section("__" #name "_sched_class") 2650 2651 /* Defined in include/asm-generic/vmlinux.lds.h */ 2652 extern struct sched_class __sched_class_highest[]; 2653 extern struct sched_class __sched_class_lowest[]; 2654 2655 extern const struct sched_class stop_sched_class; 2656 extern const struct sched_class dl_sched_class; 2657 extern const struct sched_class rt_sched_class; 2658 extern const struct sched_class fair_sched_class; 2659 extern const struct sched_class idle_sched_class; 2660 2661 /* 2662 * Iterate only active classes. SCX can take over all fair tasks or be 2663 * completely disabled. If the former, skip fair. If the latter, skip SCX. 2664 */ 2665 static inline const struct sched_class *next_active_class(const struct sched_class *class) 2666 { 2667 class++; 2668 #ifdef CONFIG_SCHED_CLASS_EXT 2669 if (scx_switched_all() && class == &fair_sched_class) 2670 class++; 2671 if (!scx_enabled() && class == &ext_sched_class) 2672 class++; 2673 #endif 2674 return class; 2675 } 2676 2677 #define for_class_range(class, _from, _to) \ 2678 for (class = (_from); class < (_to); class++) 2679 2680 #define for_each_class(class) \ 2681 for_class_range(class, __sched_class_highest, __sched_class_lowest) 2682 2683 #define for_active_class_range(class, _from, _to) \ 2684 for (class = (_from); class != (_to); class = next_active_class(class)) 2685 2686 #define for_each_active_class(class) \ 2687 for_active_class_range(class, __sched_class_highest, __sched_class_lowest) 2688 2689 #define sched_class_above(_a, _b) ((_a) < (_b)) 2690 2691 static inline bool sched_stop_runnable(struct rq *rq) 2692 { 2693 return rq->stop && task_on_rq_queued(rq->stop); 2694 } 2695 2696 static inline bool sched_dl_runnable(struct rq *rq) 2697 { 2698 return rq->dl.dl_nr_running > 0; 2699 } 2700 2701 static inline bool sched_rt_runnable(struct rq *rq) 2702 { 2703 return rq->rt.rt_queued > 0; 2704 } 2705 2706 static inline bool sched_fair_runnable(struct rq *rq) 2707 { 2708 return rq->cfs.nr_queued > 0; 2709 } 2710 2711 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, 2712 struct rq_flags *rf); 2713 extern struct task_struct *pick_task_idle(struct rq *rq, struct rq_flags *rf); 2714 2715 #define SCA_CHECK 0x01 2716 #define SCA_MIGRATE_DISABLE 0x02 2717 #define SCA_MIGRATE_ENABLE 0x04 2718 #define SCA_USER 0x08 2719 2720 extern void update_group_capacity(struct sched_domain *sd, int cpu); 2721 2722 extern void sched_balance_trigger(struct rq *rq); 2723 2724 extern int __set_cpus_allowed_ptr(struct task_struct *p, struct affinity_context *ctx); 2725 extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx); 2726 2727 static inline bool task_allowed_on_cpu(struct task_struct *p, int cpu) 2728 { 2729 /* When not in the task's cpumask, no point in looking further. */ 2730 if (!cpumask_test_cpu(cpu, p->cpus_ptr)) 2731 return false; 2732 2733 /* Can @cpu run a user thread? */ 2734 if (!(p->flags & PF_KTHREAD) && !task_cpu_possible(cpu, p)) 2735 return false; 2736 2737 return true; 2738 } 2739 2740 static inline cpumask_t *alloc_user_cpus_ptr(int node) 2741 { 2742 /* 2743 * See set_cpus_allowed_force() above for the rcu_head usage. 2744 */ 2745 int size = max_t(int, cpumask_size(), sizeof(struct rcu_head)); 2746 2747 return kmalloc_node(size, GFP_KERNEL, node); 2748 } 2749 2750 static inline struct task_struct *get_push_task(struct rq *rq) 2751 { 2752 struct task_struct *p = rq->donor; 2753 2754 lockdep_assert_rq_held(rq); 2755 2756 if (rq->push_busy) 2757 return NULL; 2758 2759 if (p->nr_cpus_allowed == 1) 2760 return NULL; 2761 2762 if (p->migration_disabled) 2763 return NULL; 2764 2765 rq->push_busy = true; 2766 return get_task_struct(p); 2767 } 2768 2769 extern int push_cpu_stop(void *arg); 2770 2771 #ifdef CONFIG_CPU_IDLE 2772 2773 static inline void idle_set_state(struct rq *rq, 2774 struct cpuidle_state *idle_state) 2775 { 2776 rq->idle_state = idle_state; 2777 } 2778 2779 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 2780 { 2781 WARN_ON_ONCE(!rcu_read_lock_held()); 2782 2783 return rq->idle_state; 2784 } 2785 2786 #else /* !CONFIG_CPU_IDLE: */ 2787 2788 static inline void idle_set_state(struct rq *rq, 2789 struct cpuidle_state *idle_state) 2790 { 2791 } 2792 2793 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 2794 { 2795 return NULL; 2796 } 2797 2798 #endif /* !CONFIG_CPU_IDLE */ 2799 2800 extern void schedule_idle(void); 2801 asmlinkage void schedule_user(void); 2802 2803 extern void sysrq_sched_debug_show(void); 2804 extern void sched_init_granularity(void); 2805 extern void update_max_interval(void); 2806 2807 extern void init_sched_dl_class(void); 2808 extern void init_sched_rt_class(void); 2809 extern void init_sched_fair_class(void); 2810 2811 extern void resched_curr(struct rq *rq); 2812 extern void resched_curr_lazy(struct rq *rq); 2813 extern void resched_cpu(int cpu); 2814 2815 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime); 2816 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq); 2817 2818 extern void init_dl_entity(struct sched_dl_entity *dl_se); 2819 2820 extern void init_cfs_throttle_work(struct task_struct *p); 2821 2822 #define BW_SHIFT 20 2823 #define BW_UNIT (1 << BW_SHIFT) 2824 #define RATIO_SHIFT 8 2825 #define MAX_BW_BITS (64 - BW_SHIFT) 2826 #define MAX_BW ((1ULL << MAX_BW_BITS) - 1) 2827 2828 extern unsigned long to_ratio(u64 period, u64 runtime); 2829 2830 extern void init_entity_runnable_average(struct sched_entity *se); 2831 extern void post_init_entity_util_avg(struct task_struct *p); 2832 2833 #ifdef CONFIG_NO_HZ_FULL 2834 extern bool sched_can_stop_tick(struct rq *rq); 2835 extern int __init sched_tick_offload_init(void); 2836 2837 /* 2838 * Tick may be needed by tasks in the runqueue depending on their policy and 2839 * requirements. If tick is needed, lets send the target an IPI to kick it out of 2840 * nohz mode if necessary. 2841 */ 2842 static inline void sched_update_tick_dependency(struct rq *rq) 2843 { 2844 int cpu = cpu_of(rq); 2845 2846 if (!tick_nohz_full_cpu(cpu)) 2847 return; 2848 2849 if (sched_can_stop_tick(rq)) 2850 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED); 2851 else 2852 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED); 2853 } 2854 #else /* !CONFIG_NO_HZ_FULL: */ 2855 static inline int sched_tick_offload_init(void) { return 0; } 2856 static inline void sched_update_tick_dependency(struct rq *rq) { } 2857 #endif /* !CONFIG_NO_HZ_FULL */ 2858 2859 static inline void add_nr_running(struct rq *rq, unsigned count) 2860 { 2861 unsigned prev_nr = rq->nr_running; 2862 2863 rq->nr_running = prev_nr + count; 2864 if (trace_sched_update_nr_running_tp_enabled()) { 2865 call_trace_sched_update_nr_running(rq, count); 2866 } 2867 2868 if (prev_nr < 2 && rq->nr_running >= 2) 2869 set_rd_overloaded(rq->rd, 1); 2870 2871 sched_update_tick_dependency(rq); 2872 } 2873 2874 static inline void sub_nr_running(struct rq *rq, unsigned count) 2875 { 2876 rq->nr_running -= count; 2877 if (trace_sched_update_nr_running_tp_enabled()) { 2878 call_trace_sched_update_nr_running(rq, -count); 2879 } 2880 2881 /* Check if we still need preemption */ 2882 sched_update_tick_dependency(rq); 2883 } 2884 2885 static inline void __block_task(struct rq *rq, struct task_struct *p) 2886 { 2887 if (p->sched_contributes_to_load) 2888 rq->nr_uninterruptible++; 2889 2890 if (p->in_iowait) { 2891 atomic_inc(&rq->nr_iowait); 2892 delayacct_blkio_start(); 2893 } 2894 2895 ASSERT_EXCLUSIVE_WRITER(p->on_rq); 2896 2897 /* 2898 * The moment this write goes through, ttwu() can swoop in and migrate 2899 * this task, rendering our rq->__lock ineffective. 2900 * 2901 * __schedule() try_to_wake_up() 2902 * LOCK rq->__lock LOCK p->pi_lock 2903 * pick_next_task() 2904 * pick_next_task_fair() 2905 * pick_next_entity() 2906 * dequeue_entities() 2907 * __block_task() 2908 * RELEASE p->on_rq = 0 if (p->on_rq && ...) 2909 * break; 2910 * 2911 * ACQUIRE (after ctrl-dep) 2912 * 2913 * cpu = select_task_rq(); 2914 * set_task_cpu(p, cpu); 2915 * ttwu_queue() 2916 * ttwu_do_activate() 2917 * LOCK rq->__lock 2918 * activate_task() 2919 * STORE p->on_rq = 1 2920 * UNLOCK rq->__lock 2921 * 2922 * Callers must ensure to not reference @p after this -- we no longer 2923 * own it. 2924 */ 2925 smp_store_release(&p->on_rq, 0); 2926 } 2927 2928 extern void activate_task(struct rq *rq, struct task_struct *p, int flags); 2929 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags); 2930 2931 extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags); 2932 2933 #ifdef CONFIG_PREEMPT_RT 2934 # define SCHED_NR_MIGRATE_BREAK 8 2935 #else 2936 # define SCHED_NR_MIGRATE_BREAK 32 2937 #endif 2938 2939 extern __read_mostly unsigned int sysctl_sched_nr_migrate; 2940 extern __read_mostly unsigned int sysctl_sched_migration_cost; 2941 2942 extern unsigned int sysctl_sched_base_slice; 2943 2944 extern int sysctl_resched_latency_warn_ms; 2945 extern int sysctl_resched_latency_warn_once; 2946 2947 extern unsigned int sysctl_sched_tunable_scaling; 2948 2949 extern unsigned int sysctl_numa_balancing_scan_delay; 2950 extern unsigned int sysctl_numa_balancing_scan_period_min; 2951 extern unsigned int sysctl_numa_balancing_scan_period_max; 2952 extern unsigned int sysctl_numa_balancing_scan_size; 2953 extern unsigned int sysctl_numa_balancing_hot_threshold; 2954 2955 #ifdef CONFIG_SCHED_HRTICK 2956 2957 /* 2958 * Use hrtick when: 2959 * - enabled by features 2960 * - hrtimer is actually high res 2961 */ 2962 static inline int hrtick_enabled(struct rq *rq) 2963 { 2964 if (!cpu_active(cpu_of(rq))) 2965 return 0; 2966 return hrtimer_is_hres_active(&rq->hrtick_timer); 2967 } 2968 2969 static inline int hrtick_enabled_fair(struct rq *rq) 2970 { 2971 if (!sched_feat(HRTICK)) 2972 return 0; 2973 return hrtick_enabled(rq); 2974 } 2975 2976 static inline int hrtick_enabled_dl(struct rq *rq) 2977 { 2978 if (!sched_feat(HRTICK_DL)) 2979 return 0; 2980 return hrtick_enabled(rq); 2981 } 2982 2983 extern void hrtick_start(struct rq *rq, u64 delay); 2984 2985 #else /* !CONFIG_SCHED_HRTICK: */ 2986 2987 static inline int hrtick_enabled_fair(struct rq *rq) 2988 { 2989 return 0; 2990 } 2991 2992 static inline int hrtick_enabled_dl(struct rq *rq) 2993 { 2994 return 0; 2995 } 2996 2997 static inline int hrtick_enabled(struct rq *rq) 2998 { 2999 return 0; 3000 } 3001 3002 #endif /* !CONFIG_SCHED_HRTICK */ 3003 3004 #ifndef arch_scale_freq_tick 3005 static __always_inline void arch_scale_freq_tick(void) { } 3006 #endif 3007 3008 #ifndef arch_scale_freq_capacity 3009 /** 3010 * arch_scale_freq_capacity - get the frequency scale factor of a given CPU. 3011 * @cpu: the CPU in question. 3012 * 3013 * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e. 3014 * 3015 * f_curr 3016 * ------ * SCHED_CAPACITY_SCALE 3017 * f_max 3018 */ 3019 static __always_inline 3020 unsigned long arch_scale_freq_capacity(int cpu) 3021 { 3022 return SCHED_CAPACITY_SCALE; 3023 } 3024 #endif 3025 3026 /* 3027 * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to 3028 * acquire rq lock instead of rq_lock(). So at the end of these two functions 3029 * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of 3030 * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning. 3031 */ 3032 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) 3033 { 3034 rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 3035 rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 3036 } 3037 3038 #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...) \ 3039 __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__) \ 3040 static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2) \ 3041 { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t; \ 3042 _lock; return _t; } 3043 3044 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2) 3045 { 3046 #ifdef CONFIG_SCHED_CORE 3047 /* 3048 * In order to not have {0,2},{1,3} turn into into an AB-BA, 3049 * order by core-id first and cpu-id second. 3050 * 3051 * Notably: 3052 * 3053 * double_rq_lock(0,3); will take core-0, core-1 lock 3054 * double_rq_lock(1,2); will take core-1, core-0 lock 3055 * 3056 * when only cpu-id is considered. 3057 */ 3058 if (rq1->core->cpu < rq2->core->cpu) 3059 return true; 3060 if (rq1->core->cpu > rq2->core->cpu) 3061 return false; 3062 3063 /* 3064 * __sched_core_flip() relies on SMT having cpu-id lock order. 3065 */ 3066 #endif /* CONFIG_SCHED_CORE */ 3067 return rq1->cpu < rq2->cpu; 3068 } 3069 3070 extern void double_rq_lock(struct rq *rq1, struct rq *rq2); 3071 3072 #ifdef CONFIG_PREEMPTION 3073 3074 /* 3075 * fair double_lock_balance: Safely acquires both rq->locks in a fair 3076 * way at the expense of forcing extra atomic operations in all 3077 * invocations. This assures that the double_lock is acquired using the 3078 * same underlying policy as the spinlock_t on this architecture, which 3079 * reduces latency compared to the unfair variant below. However, it 3080 * also adds more overhead and therefore may reduce throughput. 3081 */ 3082 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 3083 __releases(this_rq->lock) 3084 __acquires(busiest->lock) 3085 __acquires(this_rq->lock) 3086 { 3087 raw_spin_rq_unlock(this_rq); 3088 double_rq_lock(this_rq, busiest); 3089 3090 return 1; 3091 } 3092 3093 #else /* !CONFIG_PREEMPTION: */ 3094 /* 3095 * Unfair double_lock_balance: Optimizes throughput at the expense of 3096 * latency by eliminating extra atomic operations when the locks are 3097 * already in proper order on entry. This favors lower CPU-ids and will 3098 * grant the double lock to lower CPUs over higher ids under contention, 3099 * regardless of entry order into the function. 3100 */ 3101 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 3102 __releases(this_rq->lock) 3103 __acquires(busiest->lock) 3104 __acquires(this_rq->lock) 3105 { 3106 if (__rq_lockp(this_rq) == __rq_lockp(busiest) || 3107 likely(raw_spin_rq_trylock(busiest))) { 3108 double_rq_clock_clear_update(this_rq, busiest); 3109 return 0; 3110 } 3111 3112 if (rq_order_less(this_rq, busiest)) { 3113 raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING); 3114 double_rq_clock_clear_update(this_rq, busiest); 3115 return 0; 3116 } 3117 3118 raw_spin_rq_unlock(this_rq); 3119 double_rq_lock(this_rq, busiest); 3120 3121 return 1; 3122 } 3123 3124 #endif /* !CONFIG_PREEMPTION */ 3125 3126 /* 3127 * double_lock_balance - lock the busiest runqueue, this_rq is locked already. 3128 */ 3129 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest) 3130 { 3131 lockdep_assert_irqs_disabled(); 3132 3133 return _double_lock_balance(this_rq, busiest); 3134 } 3135 3136 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest) 3137 __releases(busiest->lock) 3138 { 3139 if (__rq_lockp(this_rq) != __rq_lockp(busiest)) 3140 raw_spin_rq_unlock(busiest); 3141 lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_); 3142 } 3143 3144 static inline void double_lock(spinlock_t *l1, spinlock_t *l2) 3145 { 3146 if (l1 > l2) 3147 swap(l1, l2); 3148 3149 spin_lock(l1); 3150 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 3151 } 3152 3153 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2) 3154 { 3155 if (l1 > l2) 3156 swap(l1, l2); 3157 3158 spin_lock_irq(l1); 3159 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 3160 } 3161 3162 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2) 3163 { 3164 if (l1 > l2) 3165 swap(l1, l2); 3166 3167 raw_spin_lock(l1); 3168 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 3169 } 3170 3171 static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2) 3172 { 3173 raw_spin_unlock(l1); 3174 raw_spin_unlock(l2); 3175 } 3176 3177 DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t, 3178 double_raw_lock(_T->lock, _T->lock2), 3179 double_raw_unlock(_T->lock, _T->lock2)) 3180 3181 /* 3182 * double_rq_unlock - safely unlock two runqueues 3183 * 3184 * Note this does not restore interrupts like task_rq_unlock, 3185 * you need to do so manually after calling. 3186 */ 3187 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 3188 __releases(rq1->lock) 3189 __releases(rq2->lock) 3190 { 3191 if (__rq_lockp(rq1) != __rq_lockp(rq2)) 3192 raw_spin_rq_unlock(rq2); 3193 else 3194 __release(rq2->lock); 3195 raw_spin_rq_unlock(rq1); 3196 } 3197 3198 extern void set_rq_online (struct rq *rq); 3199 extern void set_rq_offline(struct rq *rq); 3200 3201 extern bool sched_smp_initialized; 3202 3203 DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq, 3204 double_rq_lock(_T->lock, _T->lock2), 3205 double_rq_unlock(_T->lock, _T->lock2)) 3206 3207 extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq); 3208 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq); 3209 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq); 3210 3211 extern bool sched_debug_verbose; 3212 3213 extern void print_cfs_stats(struct seq_file *m, int cpu); 3214 extern void print_rt_stats(struct seq_file *m, int cpu); 3215 extern void print_dl_stats(struct seq_file *m, int cpu); 3216 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 3217 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq); 3218 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq); 3219 3220 extern void resched_latency_warn(int cpu, u64 latency); 3221 3222 #ifdef CONFIG_NUMA_BALANCING 3223 extern void show_numa_stats(struct task_struct *p, struct seq_file *m); 3224 extern void 3225 print_numa_stats(struct seq_file *m, int node, unsigned long tsf, 3226 unsigned long tpf, unsigned long gsf, unsigned long gpf); 3227 #endif /* CONFIG_NUMA_BALANCING */ 3228 3229 extern void init_cfs_rq(struct cfs_rq *cfs_rq); 3230 extern void init_rt_rq(struct rt_rq *rt_rq); 3231 extern void init_dl_rq(struct dl_rq *dl_rq); 3232 3233 extern void cfs_bandwidth_usage_inc(void); 3234 extern void cfs_bandwidth_usage_dec(void); 3235 3236 #ifdef CONFIG_NO_HZ_COMMON 3237 3238 #define NOHZ_BALANCE_KICK_BIT 0 3239 #define NOHZ_STATS_KICK_BIT 1 3240 #define NOHZ_NEWILB_KICK_BIT 2 3241 #define NOHZ_NEXT_KICK_BIT 3 3242 3243 /* Run sched_balance_domains() */ 3244 #define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT) 3245 /* Update blocked load */ 3246 #define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT) 3247 /* Update blocked load when entering idle */ 3248 #define NOHZ_NEWILB_KICK BIT(NOHZ_NEWILB_KICK_BIT) 3249 /* Update nohz.next_balance */ 3250 #define NOHZ_NEXT_KICK BIT(NOHZ_NEXT_KICK_BIT) 3251 3252 #define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK) 3253 3254 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags) 3255 3256 extern void nohz_balance_exit_idle(struct rq *rq); 3257 #else /* !CONFIG_NO_HZ_COMMON: */ 3258 static inline void nohz_balance_exit_idle(struct rq *rq) { } 3259 #endif /* !CONFIG_NO_HZ_COMMON */ 3260 3261 #ifdef CONFIG_NO_HZ_COMMON 3262 extern void nohz_run_idle_balance(int cpu); 3263 #else 3264 static inline void nohz_run_idle_balance(int cpu) { } 3265 #endif 3266 3267 #include "stats.h" 3268 3269 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS) 3270 3271 extern void __sched_core_account_forceidle(struct rq *rq); 3272 3273 static inline void sched_core_account_forceidle(struct rq *rq) 3274 { 3275 if (schedstat_enabled()) 3276 __sched_core_account_forceidle(rq); 3277 } 3278 3279 extern void __sched_core_tick(struct rq *rq); 3280 3281 static inline void sched_core_tick(struct rq *rq) 3282 { 3283 if (sched_core_enabled(rq) && schedstat_enabled()) 3284 __sched_core_tick(rq); 3285 } 3286 3287 #else /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS): */ 3288 3289 static inline void sched_core_account_forceidle(struct rq *rq) { } 3290 3291 static inline void sched_core_tick(struct rq *rq) { } 3292 3293 #endif /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS) */ 3294 3295 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 3296 3297 struct irqtime { 3298 u64 total; 3299 u64 tick_delta; 3300 u64 irq_start_time; 3301 struct u64_stats_sync sync; 3302 }; 3303 3304 DECLARE_PER_CPU(struct irqtime, cpu_irqtime); 3305 extern int sched_clock_irqtime; 3306 3307 static inline int irqtime_enabled(void) 3308 { 3309 return sched_clock_irqtime; 3310 } 3311 3312 /* 3313 * Returns the irqtime minus the softirq time computed by ksoftirqd. 3314 * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime 3315 * and never move forward. 3316 */ 3317 static inline u64 irq_time_read(int cpu) 3318 { 3319 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu); 3320 unsigned int seq; 3321 u64 total; 3322 3323 do { 3324 seq = __u64_stats_fetch_begin(&irqtime->sync); 3325 total = irqtime->total; 3326 } while (__u64_stats_fetch_retry(&irqtime->sync, seq)); 3327 3328 return total; 3329 } 3330 3331 #else /* !CONFIG_IRQ_TIME_ACCOUNTING: */ 3332 3333 static inline int irqtime_enabled(void) 3334 { 3335 return 0; 3336 } 3337 3338 #endif /* !CONFIG_IRQ_TIME_ACCOUNTING */ 3339 3340 #ifdef CONFIG_CPU_FREQ 3341 3342 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data); 3343 3344 /** 3345 * cpufreq_update_util - Take a note about CPU utilization changes. 3346 * @rq: Runqueue to carry out the update for. 3347 * @flags: Update reason flags. 3348 * 3349 * This function is called by the scheduler on the CPU whose utilization is 3350 * being updated. 3351 * 3352 * It can only be called from RCU-sched read-side critical sections. 3353 * 3354 * The way cpufreq is currently arranged requires it to evaluate the CPU 3355 * performance state (frequency/voltage) on a regular basis to prevent it from 3356 * being stuck in a completely inadequate performance level for too long. 3357 * That is not guaranteed to happen if the updates are only triggered from CFS 3358 * and DL, though, because they may not be coming in if only RT tasks are 3359 * active all the time (or there are RT tasks only). 3360 * 3361 * As a workaround for that issue, this function is called periodically by the 3362 * RT sched class to trigger extra cpufreq updates to prevent it from stalling, 3363 * but that really is a band-aid. Going forward it should be replaced with 3364 * solutions targeted more specifically at RT tasks. 3365 */ 3366 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) 3367 { 3368 struct update_util_data *data; 3369 3370 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data, 3371 cpu_of(rq))); 3372 if (data) 3373 data->func(data, rq_clock(rq), flags); 3374 } 3375 #else /* !CONFIG_CPU_FREQ: */ 3376 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) { } 3377 #endif /* !CONFIG_CPU_FREQ */ 3378 3379 #ifdef arch_scale_freq_capacity 3380 # ifndef arch_scale_freq_invariant 3381 # define arch_scale_freq_invariant() true 3382 # endif 3383 #else 3384 # define arch_scale_freq_invariant() false 3385 #endif 3386 3387 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs, 3388 unsigned long *min, 3389 unsigned long *max); 3390 3391 unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual, 3392 unsigned long min, 3393 unsigned long max); 3394 3395 3396 /* 3397 * Verify the fitness of task @p to run on @cpu taking into account the 3398 * CPU original capacity and the runtime/deadline ratio of the task. 3399 * 3400 * The function will return true if the original capacity of @cpu is 3401 * greater than or equal to task's deadline density right shifted by 3402 * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise. 3403 */ 3404 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu) 3405 { 3406 unsigned long cap = arch_scale_cpu_capacity(cpu); 3407 3408 return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT); 3409 } 3410 3411 static inline unsigned long cpu_bw_dl(struct rq *rq) 3412 { 3413 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT; 3414 } 3415 3416 static inline unsigned long cpu_util_dl(struct rq *rq) 3417 { 3418 return READ_ONCE(rq->avg_dl.util_avg); 3419 } 3420 3421 3422 extern unsigned long cpu_util_cfs(int cpu); 3423 extern unsigned long cpu_util_cfs_boost(int cpu); 3424 3425 static inline unsigned long cpu_util_rt(struct rq *rq) 3426 { 3427 return READ_ONCE(rq->avg_rt.util_avg); 3428 } 3429 3430 #ifdef CONFIG_UCLAMP_TASK 3431 3432 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id); 3433 3434 /* 3435 * When uclamp is compiled in, the aggregation at rq level is 'turned off' 3436 * by default in the fast path and only gets turned on once userspace performs 3437 * an operation that requires it. 3438 * 3439 * Returns true if userspace opted-in to use uclamp and aggregation at rq level 3440 * hence is active. 3441 */ 3442 static inline bool uclamp_is_used(void) 3443 { 3444 return static_branch_likely(&sched_uclamp_used); 3445 } 3446 3447 /* 3448 * Enabling static branches would get the cpus_read_lock(), 3449 * check whether uclamp_is_used before enable it to avoid always 3450 * calling cpus_read_lock(). Because we never disable this 3451 * static key once enable it. 3452 */ 3453 static inline void sched_uclamp_enable(void) 3454 { 3455 if (!uclamp_is_used()) 3456 static_branch_enable(&sched_uclamp_used); 3457 } 3458 3459 static inline unsigned long uclamp_rq_get(struct rq *rq, 3460 enum uclamp_id clamp_id) 3461 { 3462 return READ_ONCE(rq->uclamp[clamp_id].value); 3463 } 3464 3465 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, 3466 unsigned int value) 3467 { 3468 WRITE_ONCE(rq->uclamp[clamp_id].value, value); 3469 } 3470 3471 static inline bool uclamp_rq_is_idle(struct rq *rq) 3472 { 3473 return rq->uclamp_flags & UCLAMP_FLAG_IDLE; 3474 } 3475 3476 /* Is the rq being capped/throttled by uclamp_max? */ 3477 static inline bool uclamp_rq_is_capped(struct rq *rq) 3478 { 3479 unsigned long rq_util; 3480 unsigned long max_util; 3481 3482 if (!uclamp_is_used()) 3483 return false; 3484 3485 rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq); 3486 max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value); 3487 3488 return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util; 3489 } 3490 3491 #define for_each_clamp_id(clamp_id) \ 3492 for ((clamp_id) = 0; (clamp_id) < UCLAMP_CNT; (clamp_id)++) 3493 3494 extern unsigned int sysctl_sched_uclamp_util_min_rt_default; 3495 3496 3497 static inline unsigned int uclamp_none(enum uclamp_id clamp_id) 3498 { 3499 if (clamp_id == UCLAMP_MIN) 3500 return 0; 3501 return SCHED_CAPACITY_SCALE; 3502 } 3503 3504 /* Integer rounded range for each bucket */ 3505 #define UCLAMP_BUCKET_DELTA DIV_ROUND_CLOSEST(SCHED_CAPACITY_SCALE, UCLAMP_BUCKETS) 3506 3507 static inline unsigned int uclamp_bucket_id(unsigned int clamp_value) 3508 { 3509 return min_t(unsigned int, clamp_value / UCLAMP_BUCKET_DELTA, UCLAMP_BUCKETS - 1); 3510 } 3511 3512 static inline void 3513 uclamp_se_set(struct uclamp_se *uc_se, unsigned int value, bool user_defined) 3514 { 3515 uc_se->value = value; 3516 uc_se->bucket_id = uclamp_bucket_id(value); 3517 uc_se->user_defined = user_defined; 3518 } 3519 3520 #else /* !CONFIG_UCLAMP_TASK: */ 3521 3522 static inline unsigned long 3523 uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id) 3524 { 3525 if (clamp_id == UCLAMP_MIN) 3526 return 0; 3527 3528 return SCHED_CAPACITY_SCALE; 3529 } 3530 3531 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; } 3532 3533 static inline bool uclamp_is_used(void) 3534 { 3535 return false; 3536 } 3537 3538 static inline void sched_uclamp_enable(void) {} 3539 3540 static inline unsigned long 3541 uclamp_rq_get(struct rq *rq, enum uclamp_id clamp_id) 3542 { 3543 if (clamp_id == UCLAMP_MIN) 3544 return 0; 3545 3546 return SCHED_CAPACITY_SCALE; 3547 } 3548 3549 static inline void 3550 uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, unsigned int value) 3551 { 3552 } 3553 3554 static inline bool uclamp_rq_is_idle(struct rq *rq) 3555 { 3556 return false; 3557 } 3558 3559 #endif /* !CONFIG_UCLAMP_TASK */ 3560 3561 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 3562 3563 static inline unsigned long cpu_util_irq(struct rq *rq) 3564 { 3565 return READ_ONCE(rq->avg_irq.util_avg); 3566 } 3567 3568 static inline 3569 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 3570 { 3571 util *= (max - irq); 3572 util /= max; 3573 3574 return util; 3575 3576 } 3577 3578 #else /* !CONFIG_HAVE_SCHED_AVG_IRQ: */ 3579 3580 static inline unsigned long cpu_util_irq(struct rq *rq) 3581 { 3582 return 0; 3583 } 3584 3585 static inline 3586 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 3587 { 3588 return util; 3589 } 3590 3591 #endif /* !CONFIG_HAVE_SCHED_AVG_IRQ */ 3592 3593 extern void __setparam_fair(struct task_struct *p, const struct sched_attr *attr); 3594 3595 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) 3596 3597 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus))) 3598 3599 DECLARE_STATIC_KEY_FALSE(sched_energy_present); 3600 3601 static inline bool sched_energy_enabled(void) 3602 { 3603 return static_branch_unlikely(&sched_energy_present); 3604 } 3605 3606 #else /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL): */ 3607 3608 #define perf_domain_span(pd) NULL 3609 3610 static inline bool sched_energy_enabled(void) { return false; } 3611 3612 #endif /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */ 3613 3614 #ifdef CONFIG_MEMBARRIER 3615 3616 /* 3617 * The scheduler provides memory barriers required by membarrier between: 3618 * - prior user-space memory accesses and store to rq->membarrier_state, 3619 * - store to rq->membarrier_state and following user-space memory accesses. 3620 * In the same way it provides those guarantees around store to rq->curr. 3621 */ 3622 static inline void membarrier_switch_mm(struct rq *rq, 3623 struct mm_struct *prev_mm, 3624 struct mm_struct *next_mm) 3625 { 3626 int membarrier_state; 3627 3628 if (prev_mm == next_mm) 3629 return; 3630 3631 membarrier_state = atomic_read(&next_mm->membarrier_state); 3632 if (READ_ONCE(rq->membarrier_state) == membarrier_state) 3633 return; 3634 3635 WRITE_ONCE(rq->membarrier_state, membarrier_state); 3636 } 3637 3638 #else /* !CONFIG_MEMBARRIER: */ 3639 3640 static inline void membarrier_switch_mm(struct rq *rq, 3641 struct mm_struct *prev_mm, 3642 struct mm_struct *next_mm) 3643 { 3644 } 3645 3646 #endif /* !CONFIG_MEMBARRIER */ 3647 3648 static inline bool is_per_cpu_kthread(struct task_struct *p) 3649 { 3650 if (!(p->flags & PF_KTHREAD)) 3651 return false; 3652 3653 if (p->nr_cpus_allowed != 1) 3654 return false; 3655 3656 return true; 3657 } 3658 3659 extern void swake_up_all_locked(struct swait_queue_head *q); 3660 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait); 3661 3662 extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags); 3663 3664 #ifdef CONFIG_PREEMPT_DYNAMIC 3665 extern int preempt_dynamic_mode; 3666 extern int sched_dynamic_mode(const char *str); 3667 extern void sched_dynamic_update(int mode); 3668 #endif 3669 extern const char *preempt_modes[]; 3670 3671 #ifdef CONFIG_SCHED_MM_CID 3672 3673 #define SCHED_MM_CID_PERIOD_NS (100ULL * 1000000) /* 100ms */ 3674 #define MM_CID_SCAN_DELAY 100 /* 100ms */ 3675 3676 extern raw_spinlock_t cid_lock; 3677 extern int use_cid_lock; 3678 3679 extern void sched_mm_cid_migrate_from(struct task_struct *t); 3680 extern void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t); 3681 extern void task_tick_mm_cid(struct rq *rq, struct task_struct *curr); 3682 extern void init_sched_mm_cid(struct task_struct *t); 3683 3684 static inline void __mm_cid_put(struct mm_struct *mm, int cid) 3685 { 3686 if (cid < 0) 3687 return; 3688 cpumask_clear_cpu(cid, mm_cidmask(mm)); 3689 } 3690 3691 /* 3692 * The per-mm/cpu cid can have the MM_CID_LAZY_PUT flag set or transition to 3693 * the MM_CID_UNSET state without holding the rq lock, but the rq lock needs to 3694 * be held to transition to other states. 3695 * 3696 * State transitions synchronized with cmpxchg or try_cmpxchg need to be 3697 * consistent across CPUs, which prevents use of this_cpu_cmpxchg. 3698 */ 3699 static inline void mm_cid_put_lazy(struct task_struct *t) 3700 { 3701 struct mm_struct *mm = t->mm; 3702 struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid; 3703 int cid; 3704 3705 lockdep_assert_irqs_disabled(); 3706 cid = __this_cpu_read(pcpu_cid->cid); 3707 if (!mm_cid_is_lazy_put(cid) || 3708 !try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET)) 3709 return; 3710 __mm_cid_put(mm, mm_cid_clear_lazy_put(cid)); 3711 } 3712 3713 static inline int mm_cid_pcpu_unset(struct mm_struct *mm) 3714 { 3715 struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid; 3716 int cid, res; 3717 3718 lockdep_assert_irqs_disabled(); 3719 cid = __this_cpu_read(pcpu_cid->cid); 3720 for (;;) { 3721 if (mm_cid_is_unset(cid)) 3722 return MM_CID_UNSET; 3723 /* 3724 * Attempt transition from valid or lazy-put to unset. 3725 */ 3726 res = cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, cid, MM_CID_UNSET); 3727 if (res == cid) 3728 break; 3729 cid = res; 3730 } 3731 return cid; 3732 } 3733 3734 static inline void mm_cid_put(struct mm_struct *mm) 3735 { 3736 int cid; 3737 3738 lockdep_assert_irqs_disabled(); 3739 cid = mm_cid_pcpu_unset(mm); 3740 if (cid == MM_CID_UNSET) 3741 return; 3742 __mm_cid_put(mm, mm_cid_clear_lazy_put(cid)); 3743 } 3744 3745 static inline int __mm_cid_try_get(struct task_struct *t, struct mm_struct *mm) 3746 { 3747 struct cpumask *cidmask = mm_cidmask(mm); 3748 struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid; 3749 int cid, max_nr_cid, allowed_max_nr_cid; 3750 3751 /* 3752 * After shrinking the number of threads or reducing the number 3753 * of allowed cpus, reduce the value of max_nr_cid so expansion 3754 * of cid allocation will preserve cache locality if the number 3755 * of threads or allowed cpus increase again. 3756 */ 3757 max_nr_cid = atomic_read(&mm->max_nr_cid); 3758 while ((allowed_max_nr_cid = min_t(int, READ_ONCE(mm->nr_cpus_allowed), 3759 atomic_read(&mm->mm_users))), 3760 max_nr_cid > allowed_max_nr_cid) { 3761 /* atomic_try_cmpxchg loads previous mm->max_nr_cid into max_nr_cid. */ 3762 if (atomic_try_cmpxchg(&mm->max_nr_cid, &max_nr_cid, allowed_max_nr_cid)) { 3763 max_nr_cid = allowed_max_nr_cid; 3764 break; 3765 } 3766 } 3767 /* Try to re-use recent cid. This improves cache locality. */ 3768 cid = __this_cpu_read(pcpu_cid->recent_cid); 3769 if (!mm_cid_is_unset(cid) && cid < max_nr_cid && 3770 !cpumask_test_and_set_cpu(cid, cidmask)) 3771 return cid; 3772 /* 3773 * Expand cid allocation if the maximum number of concurrency 3774 * IDs allocated (max_nr_cid) is below the number cpus allowed 3775 * and number of threads. Expanding cid allocation as much as 3776 * possible improves cache locality. 3777 */ 3778 cid = max_nr_cid; 3779 while (cid < READ_ONCE(mm->nr_cpus_allowed) && cid < atomic_read(&mm->mm_users)) { 3780 /* atomic_try_cmpxchg loads previous mm->max_nr_cid into cid. */ 3781 if (!atomic_try_cmpxchg(&mm->max_nr_cid, &cid, cid + 1)) 3782 continue; 3783 if (!cpumask_test_and_set_cpu(cid, cidmask)) 3784 return cid; 3785 } 3786 /* 3787 * Find the first available concurrency id. 3788 * Retry finding first zero bit if the mask is temporarily 3789 * filled. This only happens during concurrent remote-clear 3790 * which owns a cid without holding a rq lock. 3791 */ 3792 for (;;) { 3793 cid = cpumask_first_zero(cidmask); 3794 if (cid < READ_ONCE(mm->nr_cpus_allowed)) 3795 break; 3796 cpu_relax(); 3797 } 3798 if (cpumask_test_and_set_cpu(cid, cidmask)) 3799 return -1; 3800 3801 return cid; 3802 } 3803 3804 /* 3805 * Save a snapshot of the current runqueue time of this cpu 3806 * with the per-cpu cid value, allowing to estimate how recently it was used. 3807 */ 3808 static inline void mm_cid_snapshot_time(struct rq *rq, struct mm_struct *mm) 3809 { 3810 struct mm_cid *pcpu_cid = per_cpu_ptr(mm->pcpu_cid, cpu_of(rq)); 3811 3812 lockdep_assert_rq_held(rq); 3813 WRITE_ONCE(pcpu_cid->time, rq->clock); 3814 } 3815 3816 static inline int __mm_cid_get(struct rq *rq, struct task_struct *t, 3817 struct mm_struct *mm) 3818 { 3819 int cid; 3820 3821 /* 3822 * All allocations (even those using the cid_lock) are lock-free. If 3823 * use_cid_lock is set, hold the cid_lock to perform cid allocation to 3824 * guarantee forward progress. 3825 */ 3826 if (!READ_ONCE(use_cid_lock)) { 3827 cid = __mm_cid_try_get(t, mm); 3828 if (cid >= 0) 3829 goto end; 3830 raw_spin_lock(&cid_lock); 3831 } else { 3832 raw_spin_lock(&cid_lock); 3833 cid = __mm_cid_try_get(t, mm); 3834 if (cid >= 0) 3835 goto unlock; 3836 } 3837 3838 /* 3839 * cid concurrently allocated. Retry while forcing following 3840 * allocations to use the cid_lock to ensure forward progress. 3841 */ 3842 WRITE_ONCE(use_cid_lock, 1); 3843 /* 3844 * Set use_cid_lock before allocation. Only care about program order 3845 * because this is only required for forward progress. 3846 */ 3847 barrier(); 3848 /* 3849 * Retry until it succeeds. It is guaranteed to eventually succeed once 3850 * all newcoming allocations observe the use_cid_lock flag set. 3851 */ 3852 do { 3853 cid = __mm_cid_try_get(t, mm); 3854 cpu_relax(); 3855 } while (cid < 0); 3856 /* 3857 * Allocate before clearing use_cid_lock. Only care about 3858 * program order because this is for forward progress. 3859 */ 3860 barrier(); 3861 WRITE_ONCE(use_cid_lock, 0); 3862 unlock: 3863 raw_spin_unlock(&cid_lock); 3864 end: 3865 mm_cid_snapshot_time(rq, mm); 3866 3867 return cid; 3868 } 3869 3870 static inline int mm_cid_get(struct rq *rq, struct task_struct *t, 3871 struct mm_struct *mm) 3872 { 3873 struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid; 3874 struct cpumask *cpumask; 3875 int cid; 3876 3877 lockdep_assert_rq_held(rq); 3878 cpumask = mm_cidmask(mm); 3879 cid = __this_cpu_read(pcpu_cid->cid); 3880 if (mm_cid_is_valid(cid)) { 3881 mm_cid_snapshot_time(rq, mm); 3882 return cid; 3883 } 3884 if (mm_cid_is_lazy_put(cid)) { 3885 if (try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET)) 3886 __mm_cid_put(mm, mm_cid_clear_lazy_put(cid)); 3887 } 3888 cid = __mm_cid_get(rq, t, mm); 3889 __this_cpu_write(pcpu_cid->cid, cid); 3890 __this_cpu_write(pcpu_cid->recent_cid, cid); 3891 3892 return cid; 3893 } 3894 3895 static inline void switch_mm_cid(struct rq *rq, 3896 struct task_struct *prev, 3897 struct task_struct *next) 3898 { 3899 /* 3900 * Provide a memory barrier between rq->curr store and load of 3901 * {prev,next}->mm->pcpu_cid[cpu] on rq->curr->mm transition. 3902 * 3903 * Should be adapted if context_switch() is modified. 3904 */ 3905 if (!next->mm) { // to kernel 3906 /* 3907 * user -> kernel transition does not guarantee a barrier, but 3908 * we can use the fact that it performs an atomic operation in 3909 * mmgrab(). 3910 */ 3911 if (prev->mm) // from user 3912 smp_mb__after_mmgrab(); 3913 /* 3914 * kernel -> kernel transition does not change rq->curr->mm 3915 * state. It stays NULL. 3916 */ 3917 } else { // to user 3918 /* 3919 * kernel -> user transition does not provide a barrier 3920 * between rq->curr store and load of {prev,next}->mm->pcpu_cid[cpu]. 3921 * Provide it here. 3922 */ 3923 if (!prev->mm) { // from kernel 3924 smp_mb(); 3925 } else { // from user 3926 /* 3927 * user->user transition relies on an implicit 3928 * memory barrier in switch_mm() when 3929 * current->mm changes. If the architecture 3930 * switch_mm() does not have an implicit memory 3931 * barrier, it is emitted here. If current->mm 3932 * is unchanged, no barrier is needed. 3933 */ 3934 smp_mb__after_switch_mm(); 3935 } 3936 } 3937 if (prev->mm_cid_active) { 3938 mm_cid_snapshot_time(rq, prev->mm); 3939 mm_cid_put_lazy(prev); 3940 prev->mm_cid = -1; 3941 } 3942 if (next->mm_cid_active) 3943 next->last_mm_cid = next->mm_cid = mm_cid_get(rq, next, next->mm); 3944 } 3945 3946 #else /* !CONFIG_SCHED_MM_CID: */ 3947 static inline void switch_mm_cid(struct rq *rq, struct task_struct *prev, struct task_struct *next) { } 3948 static inline void sched_mm_cid_migrate_from(struct task_struct *t) { } 3949 static inline void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t) { } 3950 static inline void task_tick_mm_cid(struct rq *rq, struct task_struct *curr) { } 3951 static inline void init_sched_mm_cid(struct task_struct *t) { } 3952 #endif /* !CONFIG_SCHED_MM_CID */ 3953 3954 extern u64 avg_vruntime(struct cfs_rq *cfs_rq); 3955 extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se); 3956 static inline 3957 void move_queued_task_locked(struct rq *src_rq, struct rq *dst_rq, struct task_struct *task) 3958 { 3959 lockdep_assert_rq_held(src_rq); 3960 lockdep_assert_rq_held(dst_rq); 3961 3962 deactivate_task(src_rq, task, 0); 3963 set_task_cpu(task, dst_rq->cpu); 3964 activate_task(dst_rq, task, 0); 3965 } 3966 3967 static inline 3968 bool task_is_pushable(struct rq *rq, struct task_struct *p, int cpu) 3969 { 3970 if (!task_on_cpu(rq, p) && 3971 cpumask_test_cpu(cpu, &p->cpus_mask)) 3972 return true; 3973 3974 return false; 3975 } 3976 3977 #ifdef CONFIG_RT_MUTEXES 3978 3979 static inline int __rt_effective_prio(struct task_struct *pi_task, int prio) 3980 { 3981 if (pi_task) 3982 prio = min(prio, pi_task->prio); 3983 3984 return prio; 3985 } 3986 3987 static inline int rt_effective_prio(struct task_struct *p, int prio) 3988 { 3989 struct task_struct *pi_task = rt_mutex_get_top_task(p); 3990 3991 return __rt_effective_prio(pi_task, prio); 3992 } 3993 3994 #else /* !CONFIG_RT_MUTEXES: */ 3995 3996 static inline int rt_effective_prio(struct task_struct *p, int prio) 3997 { 3998 return prio; 3999 } 4000 4001 #endif /* !CONFIG_RT_MUTEXES */ 4002 4003 extern int __sched_setscheduler(struct task_struct *p, const struct sched_attr *attr, bool user, bool pi); 4004 extern int __sched_setaffinity(struct task_struct *p, struct affinity_context *ctx); 4005 extern const struct sched_class *__setscheduler_class(int policy, int prio); 4006 extern void set_load_weight(struct task_struct *p, bool update_load); 4007 extern void enqueue_task(struct rq *rq, struct task_struct *p, int flags); 4008 extern bool dequeue_task(struct rq *rq, struct task_struct *p, int flags); 4009 4010 extern struct balance_callback *splice_balance_callbacks(struct rq *rq); 4011 extern void balance_callbacks(struct rq *rq, struct balance_callback *head); 4012 4013 /* 4014 * The 'sched_change' pattern is the safe, easy and slow way of changing a 4015 * task's scheduling properties. It dequeues a task, such that the scheduler 4016 * is fully unaware of it; at which point its properties can be modified; 4017 * after which it is enqueued again. 4018 * 4019 * Typically this must be called while holding task_rq_lock, since most/all 4020 * properties are serialized under those locks. There is currently one 4021 * exception to this rule in sched/ext which only holds rq->lock. 4022 */ 4023 4024 /* 4025 * This structure is a temporary, used to preserve/convey the queueing state 4026 * of the task between sched_change_begin() and sched_change_end(). Ensuring 4027 * the task's queueing state is idempotent across the operation. 4028 */ 4029 struct sched_change_ctx { 4030 u64 prio; 4031 struct task_struct *p; 4032 int flags; 4033 bool queued; 4034 bool running; 4035 }; 4036 4037 struct sched_change_ctx *sched_change_begin(struct task_struct *p, unsigned int flags); 4038 void sched_change_end(struct sched_change_ctx *ctx); 4039 4040 DEFINE_CLASS(sched_change, struct sched_change_ctx *, 4041 sched_change_end(_T), 4042 sched_change_begin(p, flags), 4043 struct task_struct *p, unsigned int flags) 4044 4045 DEFINE_CLASS_IS_UNCONDITIONAL(sched_change) 4046 4047 #include "ext.h" 4048 4049 #endif /* _KERNEL_SCHED_SCHED_H */ 4050