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/prandom.h> 9 #include <linux/sched/affinity.h> 10 #include <linux/sched/autogroup.h> 11 #include <linux/sched/cpufreq.h> 12 #include <linux/sched/deadline.h> 13 #include <linux/sched.h> 14 #include <linux/sched/loadavg.h> 15 #include <linux/sched/mm.h> 16 #include <linux/sched/rseq_api.h> 17 #include <linux/sched/signal.h> 18 #include <linux/sched/smt.h> 19 #include <linux/sched/stat.h> 20 #include <linux/sched/sysctl.h> 21 #include <linux/sched/task_flags.h> 22 #include <linux/sched/task.h> 23 #include <linux/sched/topology.h> 24 #include <linux/atomic.h> 25 #include <linux/bitmap.h> 26 #include <linux/bug.h> 27 #include <linux/capability.h> 28 #include <linux/cgroup_api.h> 29 #include <linux/cgroup.h> 30 #include <linux/context_tracking.h> 31 #include <linux/cpufreq.h> 32 #include <linux/cpumask_api.h> 33 #include <linux/cpuset.h> 34 #include <linux/ctype.h> 35 #include <linux/file.h> 36 #include <linux/fs_api.h> 37 #include <linux/hrtimer_api.h> 38 #include <linux/interrupt.h> 39 #include <linux/irq_work.h> 40 #include <linux/jiffies.h> 41 #include <linux/kref_api.h> 42 #include <linux/kthread.h> 43 #include <linux/ktime_api.h> 44 #include <linux/lockdep_api.h> 45 #include <linux/lockdep.h> 46 #include <linux/memblock.h> 47 #include <linux/memcontrol.h> 48 #include <linux/minmax.h> 49 #include <linux/mm.h> 50 #include <linux/module.h> 51 #include <linux/mutex_api.h> 52 #include <linux/plist.h> 53 #include <linux/poll.h> 54 #include <linux/proc_fs.h> 55 #include <linux/profile.h> 56 #include <linux/psi.h> 57 #include <linux/rcupdate.h> 58 #include <linux/seq_file.h> 59 #include <linux/seqlock.h> 60 #include <linux/softirq.h> 61 #include <linux/spinlock_api.h> 62 #include <linux/static_key.h> 63 #include <linux/stop_machine.h> 64 #include <linux/syscalls_api.h> 65 #include <linux/syscalls.h> 66 #include <linux/tick.h> 67 #include <linux/topology.h> 68 #include <linux/types.h> 69 #include <linux/u64_stats_sync_api.h> 70 #include <linux/uaccess.h> 71 #include <linux/vmstat.h> 72 #include <linux/wait_api.h> 73 #include <linux/wait_bit.h> 74 #include <linux/workqueue_api.h> 75 #include <linux/delayacct.h> 76 #include <linux/mmu_context.h> 77 78 #include <trace/events/power.h> 79 #include <trace/events/sched.h> 80 81 #include "../workqueue_internal.h" 82 83 struct rq; 84 struct cfs_rq; 85 struct rt_rq; 86 struct sched_group; 87 struct cpuidle_state; 88 89 #if defined(CONFIG_PARAVIRT) && !defined(CONFIG_HAVE_PV_STEAL_CLOCK_GEN) 90 # include <asm/paravirt.h> 91 #endif 92 93 #include <asm/barrier.h> 94 95 #include "cpupri.h" 96 #include "cpudeadline.h" 97 98 /* task_struct::on_rq states: */ 99 #define TASK_ON_RQ_QUEUED 1 100 #define TASK_ON_RQ_MIGRATING 2 101 102 extern __read_mostly int scheduler_running; 103 104 extern unsigned long calc_load_update; 105 extern atomic_long_t calc_load_tasks; 106 107 extern void calc_global_load_tick(struct rq *this_rq); 108 extern long calc_load_fold_active(struct rq *this_rq, long adjust); 109 110 extern void call_trace_sched_update_nr_running(struct rq *rq, int count); 111 112 extern int sysctl_sched_rt_period; 113 extern int sysctl_sched_rt_runtime; 114 extern int sched_rr_timeslice; 115 116 /* 117 * Asymmetric CPU capacity bits 118 */ 119 struct asym_cap_data { 120 struct list_head link; 121 struct rcu_head rcu; 122 unsigned long capacity; 123 unsigned long cpus[]; 124 }; 125 126 extern struct list_head asym_cap_list; 127 128 #define cpu_capacity_span(asym_data) to_cpumask((asym_data)->cpus) 129 130 /* 131 * Helpers for converting nanosecond timing to jiffy resolution 132 */ 133 #define NS_TO_JIFFIES(time) ((unsigned long)(time) / (NSEC_PER_SEC/HZ)) 134 135 /* 136 * Increase resolution of nice-level calculations for 64-bit architectures. 137 * The extra resolution improves shares distribution and load balancing of 138 * low-weight task groups (eg. nice +19 on an autogroup), deeper task-group 139 * hierarchies, especially on larger systems. This is not a user-visible change 140 * and does not change the user-interface for setting shares/weights. 141 * 142 * We increase resolution only if we have enough bits to allow this increased 143 * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit 144 * are pretty high and the returns do not justify the increased costs. 145 * 146 * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to 147 * increase coverage and consistency always enable it on 64-bit platforms. 148 */ 149 #ifdef CONFIG_64BIT 150 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT) 151 # define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT) 152 # define scale_load_down(w) \ 153 ({ \ 154 unsigned long __w = (w); \ 155 \ 156 if (__w) \ 157 __w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \ 158 __w; \ 159 }) 160 #else 161 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT) 162 # define scale_load(w) (w) 163 # define scale_load_down(w) (w) 164 #endif 165 166 /* 167 * Task weight (visible to users) and its load (invisible to users) have 168 * independent resolution, but they should be well calibrated. We use 169 * scale_load() and scale_load_down(w) to convert between them. The 170 * following must be true: 171 * 172 * scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD 173 * 174 */ 175 #define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT) 176 177 /* 178 * Single value that decides SCHED_DEADLINE internal math precision. 179 * 10 -> just above 1us 180 * 9 -> just above 0.5us 181 */ 182 #define DL_SCALE 10 183 184 /* 185 * Single value that denotes runtime == period, ie unlimited time. 186 */ 187 #define RUNTIME_INF ((u64)~0ULL) 188 189 static inline int idle_policy(int policy) 190 { 191 return policy == SCHED_IDLE; 192 } 193 194 static inline int normal_policy(int policy) 195 { 196 #ifdef CONFIG_SCHED_CLASS_EXT 197 if (policy == SCHED_EXT) 198 return true; 199 #endif 200 return policy == SCHED_NORMAL; 201 } 202 203 static inline int fair_policy(int policy) 204 { 205 return normal_policy(policy) || policy == SCHED_BATCH; 206 } 207 208 static inline int rt_policy(int policy) 209 { 210 return policy == SCHED_FIFO || policy == SCHED_RR; 211 } 212 213 static inline int dl_policy(int policy) 214 { 215 return policy == SCHED_DEADLINE; 216 } 217 218 static inline bool valid_policy(int policy) 219 { 220 return idle_policy(policy) || fair_policy(policy) || 221 rt_policy(policy) || dl_policy(policy); 222 } 223 224 static inline int task_has_idle_policy(struct task_struct *p) 225 { 226 return idle_policy(p->policy); 227 } 228 229 static inline int task_has_rt_policy(struct task_struct *p) 230 { 231 return rt_policy(p->policy); 232 } 233 234 static inline int task_has_dl_policy(struct task_struct *p) 235 { 236 return dl_policy(p->policy); 237 } 238 239 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT) 240 241 static inline void update_avg(u64 *avg, u64 sample) 242 { 243 s64 diff = sample - *avg; 244 245 *avg += diff / 8; 246 } 247 248 /* 249 * Shifting a value by an exponent greater *or equal* to the size of said value 250 * is UB; cap at size-1. 251 */ 252 #define shr_bound(val, shift) \ 253 (val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1)) 254 255 /* 256 * cgroup weight knobs should use the common MIN, DFL and MAX values which are 257 * 1, 100 and 10000 respectively. While it loses a bit of range on both ends, it 258 * maps pretty well onto the shares value used by scheduler and the round-trip 259 * conversions preserve the original value over the entire range. 260 */ 261 static inline unsigned long sched_weight_from_cgroup(unsigned long cgrp_weight) 262 { 263 return DIV_ROUND_CLOSEST_ULL(cgrp_weight * 1024, CGROUP_WEIGHT_DFL); 264 } 265 266 static inline unsigned long sched_weight_to_cgroup(unsigned long weight) 267 { 268 return clamp_t(unsigned long, 269 DIV_ROUND_CLOSEST_ULL(weight * CGROUP_WEIGHT_DFL, 1024), 270 CGROUP_WEIGHT_MIN, CGROUP_WEIGHT_MAX); 271 } 272 273 /* 274 * !! For sched_setattr_nocheck() (kernel) only !! 275 * 276 * This is actually gross. :( 277 * 278 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE 279 * tasks, but still be able to sleep. We need this on platforms that cannot 280 * atomically change clock frequency. Remove once fast switching will be 281 * available on such platforms. 282 * 283 * SUGOV stands for SchedUtil GOVernor. 284 */ 285 #define SCHED_FLAG_SUGOV 0x10000000 286 287 #define SCHED_DL_FLAGS (SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV) 288 289 static inline bool dl_entity_is_special(const struct sched_dl_entity *dl_se) 290 { 291 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL 292 return unlikely(dl_se->flags & SCHED_FLAG_SUGOV); 293 #else 294 return false; 295 #endif 296 } 297 298 /* 299 * Tells if entity @a should preempt entity @b. 300 */ 301 static inline bool dl_entity_preempt(const struct sched_dl_entity *a, 302 const struct sched_dl_entity *b) 303 { 304 return dl_entity_is_special(a) || 305 dl_time_before(a->deadline, b->deadline); 306 } 307 308 /* 309 * This is the priority-queue data structure of the RT scheduling class: 310 */ 311 struct rt_prio_array { 312 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */ 313 struct list_head queue[MAX_RT_PRIO]; 314 }; 315 316 struct rt_bandwidth { 317 /* nests inside the rq lock: */ 318 raw_spinlock_t rt_runtime_lock; 319 ktime_t rt_period; 320 u64 rt_runtime; 321 struct hrtimer rt_period_timer; 322 unsigned int rt_period_active; 323 }; 324 325 static inline int dl_bandwidth_enabled(void) 326 { 327 return sysctl_sched_rt_runtime >= 0; 328 } 329 330 /* 331 * To keep the bandwidth of -deadline tasks under control 332 * we need some place where: 333 * - store the maximum -deadline bandwidth of each cpu; 334 * - cache the fraction of bandwidth that is currently allocated in 335 * each root domain; 336 * 337 * This is all done in the data structure below. It is similar to the 338 * one used for RT-throttling (rt_bandwidth), with the main difference 339 * that, since here we are only interested in admission control, we 340 * do not decrease any runtime while the group "executes", neither we 341 * need a timer to replenish it. 342 * 343 * With respect to SMP, bandwidth is given on a per root domain basis, 344 * meaning that: 345 * - bw (< 100%) is the deadline bandwidth of each CPU; 346 * - total_bw is the currently allocated bandwidth in each root domain; 347 */ 348 struct dl_bw { 349 raw_spinlock_t lock; 350 u64 bw; 351 u64 total_bw; 352 }; 353 354 extern void init_dl_bw(struct dl_bw *dl_b); 355 extern int sched_dl_global_validate(void); 356 extern void sched_dl_do_global(void); 357 extern int sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr); 358 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr); 359 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr, unsigned int flags); 360 extern bool __checkparam_dl(const struct sched_attr *attr); 361 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr); 362 extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 363 extern int dl_bw_deactivate(int cpu); 364 extern s64 dl_scaled_delta_exec(struct rq *rq, struct sched_dl_entity *dl_se, s64 delta_exec); 365 /* 366 * SCHED_DEADLINE supports servers (nested scheduling) with the following 367 * interface: 368 * 369 * dl_se::rq -- runqueue we belong to. 370 * 371 * dl_se::server_pick() -- nested pick_next_task(); we yield the period if this 372 * returns NULL. 373 * 374 * dl_server_update() -- called from update_curr_common(), propagates runtime 375 * to the server. 376 * 377 * dl_server_start() -- start the server when it has tasks; it will stop 378 * automatically when there are no more tasks, per 379 * dl_se::server_pick() returning NULL. 380 * 381 * dl_server_stop() -- (force) stop the server; use when updating 382 * parameters. 383 * 384 * dl_server_init() -- initializes the server. 385 * 386 * When started the dl_server will (per dl_defer) schedule a timer for its 387 * zero-laxity point -- that is, unlike regular EDF tasks which run ASAP, a 388 * server will run at the very end of its period. 389 * 390 * This is done such that any runtime from the target class can be accounted 391 * against the server -- through dl_server_update() above -- such that when it 392 * becomes time to run, it might already be out of runtime and get deferred 393 * until the next period. In this case dl_server_timer() will alternate 394 * between defer and replenish but never actually enqueue the server. 395 * 396 * Only when the target class does not manage to exhaust the server's runtime 397 * (there's actualy starvation in the given period), will the dl_server get on 398 * the runqueue. Once queued it will pick tasks from the target class and run 399 * them until either its runtime is exhaused, at which point its back to 400 * dl_server_timer, or until there are no more tasks to run, at which point 401 * the dl_server stops itself. 402 * 403 * By stopping at this point the dl_server retains bandwidth, which, if a new 404 * task wakes up imminently (starting the server again), can be used -- 405 * subject to CBS wakeup rules -- without having to wait for the next period. 406 * 407 * Additionally, because of the dl_defer behaviour the start/stop behaviour is 408 * naturally thottled to once per period, avoiding high context switch 409 * workloads from spamming the hrtimer program/cancel paths. 410 */ 411 extern void dl_server_update_idle(struct sched_dl_entity *dl_se, s64 delta_exec); 412 extern void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec); 413 extern void dl_server_start(struct sched_dl_entity *dl_se); 414 extern void dl_server_stop(struct sched_dl_entity *dl_se); 415 extern void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq, 416 dl_server_pick_f pick_task); 417 extern void sched_init_dl_servers(void); 418 419 extern void fair_server_init(struct rq *rq); 420 extern void ext_server_init(struct rq *rq); 421 extern void __dl_server_attach_root(struct sched_dl_entity *dl_se, struct rq *rq); 422 extern int dl_server_apply_params(struct sched_dl_entity *dl_se, 423 u64 runtime, u64 period, bool init); 424 extern int dl_server_attach_bw(struct sched_dl_entity *dl_se); 425 extern void dl_server_detach_bw(struct sched_dl_entity *dl_se); 426 extern int dl_server_swap_bw(struct sched_dl_entity *detach_se, 427 struct sched_dl_entity *attach_se); 428 429 static inline bool dl_server_active(struct sched_dl_entity *dl_se) 430 { 431 return dl_se->dl_server_active; 432 } 433 434 #ifdef CONFIG_CGROUP_SCHED 435 436 extern struct list_head task_groups; 437 438 #ifdef CONFIG_GROUP_SCHED_BANDWIDTH 439 extern const u64 max_bw_quota_period_us; 440 441 /* 442 * default period for group bandwidth. 443 * default: 0.1s, units: microseconds 444 */ 445 static inline u64 default_bw_period_us(void) 446 { 447 return 100000ULL; 448 } 449 #endif /* CONFIG_GROUP_SCHED_BANDWIDTH */ 450 451 struct cfs_bandwidth { 452 #ifdef CONFIG_CFS_BANDWIDTH 453 raw_spinlock_t lock; 454 ktime_t period; 455 u64 quota; 456 u64 runtime; 457 u64 burst; 458 u64 runtime_snap; 459 s64 hierarchical_quota; 460 461 u8 idle; 462 u8 period_active; 463 u8 slack_started; 464 struct hrtimer period_timer; 465 struct hrtimer slack_timer; 466 struct list_head throttled_cfs_rq; 467 468 /* Statistics: */ 469 int nr_periods; 470 int nr_throttled; 471 int nr_burst; 472 u64 throttled_time; 473 u64 burst_time; 474 #endif /* CONFIG_CFS_BANDWIDTH */ 475 }; 476 477 /* Task group related information */ 478 struct task_group { 479 struct cgroup_subsys_state css; 480 481 #ifdef CONFIG_GROUP_SCHED_WEIGHT 482 /* A positive value indicates that this is a SCHED_IDLE group. */ 483 int idle; 484 #endif 485 486 #ifdef CONFIG_FAIR_GROUP_SCHED 487 /* runqueue "owned" by this group on each CPU */ 488 struct cfs_rq __percpu *cfs_rq; 489 unsigned long shares; 490 /* 491 * load_avg can be heavily contended at clock tick time, so put 492 * it in its own cache-line separated from the fields above which 493 * will also be accessed at each tick. 494 */ 495 atomic_long_t load_avg ____cacheline_aligned; 496 atomic_long_t runnable_avg; 497 498 #endif /* CONFIG_FAIR_GROUP_SCHED */ 499 500 #ifdef CONFIG_RT_GROUP_SCHED 501 struct sched_rt_entity **rt_se; 502 struct rt_rq **rt_rq; 503 504 struct rt_bandwidth rt_bandwidth; 505 #endif 506 507 struct scx_task_group scx; 508 509 struct rcu_head rcu; 510 struct list_head list; 511 512 struct task_group *parent; 513 struct list_head siblings; 514 struct list_head children; 515 516 #ifdef CONFIG_SCHED_AUTOGROUP 517 struct autogroup *autogroup; 518 #endif 519 520 struct cfs_bandwidth cfs_bandwidth; 521 522 #ifdef CONFIG_UCLAMP_TASK_GROUP 523 /* The two decimal precision [%] value requested from user-space */ 524 unsigned int uclamp_pct[UCLAMP_CNT]; 525 /* Clamp values requested for a task group */ 526 struct uclamp_se uclamp_req[UCLAMP_CNT]; 527 /* Effective clamp values used for a task group */ 528 struct uclamp_se uclamp[UCLAMP_CNT]; 529 #endif 530 531 }; 532 533 #define ROOT_TASK_GROUP_LOAD NICE_0_LOAD 534 535 typedef int (*tg_visitor)(struct task_group *, void *); 536 537 extern int walk_tg_tree_from(struct task_group *from, 538 tg_visitor down, tg_visitor up, void *data); 539 540 /* 541 * Iterate the full tree, calling @down when first entering a node and @up when 542 * leaving it for the final time. 543 * 544 * Caller must hold rcu_lock or sufficient equivalent. 545 */ 546 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data) 547 { 548 return walk_tg_tree_from(&root_task_group, down, up, data); 549 } 550 551 static inline struct task_group *css_tg(struct cgroup_subsys_state *css) 552 { 553 return css ? container_of(css, struct task_group, css) : NULL; 554 } 555 556 extern int tg_nop(struct task_group *tg, void *data); 557 558 #ifdef CONFIG_FAIR_GROUP_SCHED 559 extern void free_fair_sched_group(struct task_group *tg); 560 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent); 561 extern void online_fair_sched_group(struct task_group *tg); 562 extern void unregister_fair_sched_group(struct task_group *tg); 563 extern void __sched_cgroup_mode_update(int mode); 564 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 565 static inline void free_fair_sched_group(struct task_group *tg) { } 566 static inline int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) 567 { 568 return 1; 569 } 570 static inline void online_fair_sched_group(struct task_group *tg) { } 571 static inline void unregister_fair_sched_group(struct task_group *tg) { } 572 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 573 574 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, 575 struct sched_entity *se, int cpu, 576 struct sched_entity *parent); 577 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b, struct cfs_bandwidth *parent); 578 579 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b); 580 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b); 581 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq); 582 extern bool cfs_task_bw_constrained(struct task_struct *p); 583 584 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, 585 struct sched_rt_entity *rt_se, int cpu, 586 struct sched_rt_entity *parent); 587 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us); 588 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us); 589 extern long sched_group_rt_runtime(struct task_group *tg); 590 extern long sched_group_rt_period(struct task_group *tg); 591 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk); 592 593 extern struct task_group *sched_create_group(struct task_group *parent); 594 extern void sched_online_group(struct task_group *tg, 595 struct task_group *parent); 596 extern void sched_destroy_group(struct task_group *tg); 597 extern void sched_release_group(struct task_group *tg); 598 599 extern void sched_move_task(struct task_struct *tsk, bool for_autogroup); 600 601 #ifdef CONFIG_FAIR_GROUP_SCHED 602 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); 603 604 extern int sched_group_set_idle(struct task_group *tg, long idle); 605 606 extern void set_task_rq_fair(struct sched_entity *se, 607 struct cfs_rq *prev, struct cfs_rq *next); 608 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 609 static inline int sched_group_set_shares(struct task_group *tg, unsigned long shares) { return 0; } 610 static inline int sched_group_set_idle(struct task_group *tg, long idle) { return 0; } 611 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 612 613 #else /* !CONFIG_CGROUP_SCHED: */ 614 615 struct cfs_bandwidth { }; 616 617 static inline bool cfs_task_bw_constrained(struct task_struct *p) { return false; } 618 619 #endif /* !CONFIG_CGROUP_SCHED */ 620 621 /* 622 * A weight of 0 or 1 can cause arithmetics problems. 623 * A weight of a cfs_rq is the sum of weights of which entities 624 * are queued on this cfs_rq, so a weight of a entity should not be 625 * too large, so as the shares value of a task group. 626 * (The default weight is 1024 - so there's no practical 627 * limitation from this.) 628 */ 629 #define MIN_SHARES (1UL << 1) 630 #define MAX_SHARES (1UL << 18) 631 632 extern void unregister_rt_sched_group(struct task_group *tg); 633 extern void free_rt_sched_group(struct task_group *tg); 634 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent); 635 636 /* 637 * u64_u32_load/u64_u32_store 638 * 639 * Use a copy of a u64 value to protect against data race. This is only 640 * applicable for 32-bits architectures. 641 */ 642 #ifdef CONFIG_64BIT 643 # define u64_u32_load_copy(var, copy) var 644 # define u64_u32_store_copy(var, copy, val) (var = val) 645 #else 646 # define u64_u32_load_copy(var, copy) \ 647 ({ \ 648 u64 __val, __val_copy; \ 649 do { \ 650 __val_copy = copy; \ 651 /* \ 652 * paired with u64_u32_store_copy(), ordering access \ 653 * to var and copy. \ 654 */ \ 655 smp_rmb(); \ 656 __val = var; \ 657 } while (__val != __val_copy); \ 658 __val; \ 659 }) 660 # define u64_u32_store_copy(var, copy, val) \ 661 do { \ 662 typeof(val) __val = (val); \ 663 var = __val; \ 664 /* \ 665 * paired with u64_u32_load_copy(), ordering access to var and \ 666 * copy. \ 667 */ \ 668 smp_wmb(); \ 669 copy = __val; \ 670 } while (0) 671 #endif 672 # define u64_u32_load(var) u64_u32_load_copy(var, var##_copy) 673 # define u64_u32_store(var, val) u64_u32_store_copy(var, var##_copy, val) 674 675 struct balance_callback { 676 struct balance_callback *next; 677 void (*func)(struct rq *rq); 678 }; 679 680 /* Fair scheduling SCHED_{NORMAL,BATCH,IDLE} related fields in a runqueue: */ 681 struct cfs_rq { 682 struct load_weight load; 683 unsigned int nr_queued; 684 unsigned int h_nr_queued; /* SCHED_{NORMAL,BATCH,IDLE} */ 685 unsigned int h_nr_runnable; /* SCHED_{NORMAL,BATCH,IDLE} */ 686 unsigned int h_nr_idle; /* SCHED_IDLE */ 687 688 s64 sum_w_vruntime; 689 u64 sum_weight; 690 u64 zero_vruntime; 691 unsigned int sum_shift; 692 693 #ifdef CONFIG_SCHED_CORE 694 unsigned int forceidle_seq; 695 u64 zero_vruntime_fi; 696 #endif 697 698 struct rb_root_cached tasks_timeline; 699 700 /* 701 * 'curr' points to the currently running entity on this cfs_rq. 702 * It is set to NULL otherwise (i.e when none are currently running). 703 */ 704 struct sched_entity *curr; 705 struct sched_entity *next; 706 707 /* 708 * CFS load tracking 709 */ 710 struct sched_entity *h_curr; 711 struct sched_avg avg; 712 #ifndef CONFIG_64BIT 713 u64 last_update_time_copy; 714 #endif 715 struct { 716 raw_spinlock_t lock ____cacheline_aligned; 717 int nr; 718 unsigned long load_avg; 719 unsigned long util_avg; 720 unsigned long runnable_avg; 721 } removed; 722 723 #ifdef CONFIG_FAIR_GROUP_SCHED 724 u64 last_update_tg_load_avg; 725 unsigned long tg_load_avg_contrib; 726 unsigned long tg_runnable_avg_contrib; 727 long propagate; 728 long prop_runnable_sum; 729 730 /* 731 * h_load = weight * f(tg) 732 * 733 * Where f(tg) is the recursive weight fraction assigned to 734 * this group. 735 */ 736 unsigned long h_load; 737 u64 last_h_load_update; 738 struct sched_entity *h_load_next; 739 740 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */ 741 742 /* 743 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in 744 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities 745 * (like users, containers etc.) 746 * 747 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU. 748 * This list is used during load balance. 749 */ 750 int on_list; 751 struct list_head leaf_cfs_rq_list; 752 struct task_group *tg; /* Group that "owns" this runqueue */ 753 754 /* Locally cached copy of our task_group's idle value */ 755 int idle; 756 757 # ifdef CONFIG_CFS_BANDWIDTH 758 int runtime_enabled; 759 s64 runtime_remaining; 760 761 u64 throttled_pelt_idle; 762 # ifndef CONFIG_64BIT 763 u64 throttled_pelt_idle_copy; 764 # endif 765 u64 throttled_clock; 766 u64 throttled_clock_pelt; 767 u64 throttled_clock_pelt_time; 768 u64 throttled_clock_self; 769 u64 throttled_clock_self_time; 770 bool throttled:1; 771 bool pelt_clock_throttled:1; 772 int throttle_count; 773 struct list_head throttled_list; 774 struct list_head throttled_csd_list; 775 struct list_head throttled_limbo_list; 776 # endif /* CONFIG_CFS_BANDWIDTH */ 777 #endif /* CONFIG_FAIR_GROUP_SCHED */ 778 }; 779 780 #ifdef CONFIG_SCHED_CLASS_EXT 781 /* scx_rq->flags, protected by the rq lock */ 782 enum scx_rq_flags { 783 /* 784 * Set while the core has the rq online, see rq_online_scx() and 785 * rq_offline_scx(). A hotplugged cpu starts scheduling before 786 * rq_online_scx(). ops.enqueue() and ops.dispatch() are called for the 787 * cpu only while it is set, see scx_rq_online() and 788 * scx_dispatch_sched(). 789 */ 790 SCX_RQ_ONLINE = 1 << 0, 791 SCX_RQ_CAN_STOP_TICK = 1 << 1, 792 /* 793 * Set while the root considers the cpu online, from its 794 * ops.cpu_online() until its ops.cpu_offline(). ecaps are delivered 795 * only while it is set. %SCX_RQ_ONLINE follows the core's rq state 796 * instead, which changes ahead of the root's view on both edges. 797 */ 798 SCX_RQ_OPS_ONLINE = 1 << 2, 799 SCX_RQ_CLK_VALID = 1 << 5, /* RQ clock is fresh and valid */ 800 SCX_RQ_BAL_CB_PENDING = 1 << 6, /* must queue a cb after dispatching */ 801 SCX_RQ_SUB_IDLE_RENOTIFY = 1 << 7, /* sub-scheds are owed update_idle() */ 802 SCX_RQ_ROOT_IDLE_RENOTIFY = 1 << 8, /* the root is owed update_idle() */ 803 SCX_RQ_PROXY_RETRY = 1 << 9, /* proxy-rejected tasks need retry */ 804 SCX_RQ_PROXY_TICK = 1 << 10, /* proxy execution requires the tick */ 805 SCX_RQ_PROXY_PENDING = 1 << 11, /* blocked donor awaits proxy resolution */ 806 SCX_RQ_PROXY_BLOCKING = 1 << 12, /* donor is being removed for sched change */ 807 808 SCX_RQ_IN_WAKEUP = 1 << 16, 809 SCX_RQ_IN_DISPATCH = 1 << 17, 810 }; 811 812 /* per-rq rescue execution state, see scx_rescue_timerfn() */ 813 struct scx_rq_rescue { 814 struct scx_dispatch_q dsq; /* stranded tasks awaiting rescue */ 815 s64 budget; /* execution token bucket, ns */ 816 u64 clock; /* last budget accrual timestamp */ 817 struct task_struct *curr; /* task being rescued, one at a time */ 818 s64 slice; /* curr's admitted slice */ 819 s64 served; /* curr's served time */ 820 struct timer_list timer; /* paces admission and escalation */ 821 u64 kill_at; /* last ejection, init before any */ 822 }; 823 824 struct scx_rq { 825 struct scx_dispatch_q local_dsq; 826 struct scx_dispatch_q reject_dsq; /* staging for rejected tasks */ 827 #ifdef CONFIG_EXT_SUB_SCHED 828 struct scx_rq_rescue rescue; 829 #endif 830 struct list_head runnable_list; /* runnable tasks on this rq */ 831 struct list_head ddsp_deferred_locals; /* deferred ddsps from enq */ 832 /* both stashed across the activate_task() in move_remote_task_to_local_dsq() */ 833 u64 remote_activate_enq_flags; 834 struct scx_sched *remote_activate_sch; 835 u32 nr_running; 836 u32 cpuperf_target; /* [0, SCHED_CAPACITY_SCALE] */ 837 bool in_select_cpu; 838 bool cpu_released; 839 u32 flags; 840 u32 nr_immed; /* ENQ_IMMED tasks on local_dsq */ 841 #ifdef CONFIG_SCHED_CORE 842 u32 lock_drop_seq; /* nr dispatch lock releases */ 843 #endif 844 u64 clock; /* current per-rq clock -- see scx_bpf_now() */ 845 #ifdef CONFIG_EXT_SUB_SCHED 846 /* sched of the open running session, see scx_cid_sched_update() */ 847 struct scx_sched *sched; 848 struct llist_head ecaps_to_sync; /* pending ecaps syncs */ 849 struct task_struct *sub_dispatch_prev; 850 u32 nr_ecaps_offline; /* marked syncs a down waits for */ 851 #endif 852 bool kick_sync_pending; 853 cpumask_var_t cpus_to_sync; 854 unsigned long kick_sync; 855 856 struct list_head sched_pcpus_to_kick; /* see kick_cpus_irq_workfn() */ 857 858 raw_spinlock_t deferred_reenq_lock; 859 struct list_head deferred_reenq_locals; /* scheds requesting reenq of local DSQ */ 860 struct list_head deferred_reenq_users; /* user DSQs requesting reenq */ 861 struct balance_callback deferred_bal_cb; 862 struct balance_callback kick_sync_bal_cb; 863 #ifdef CONFIG_NO_HZ_FULL 864 struct balance_callback proxy_tick_bal_cb; 865 #endif 866 struct irq_work deferred_irq_work; 867 struct irq_work kick_cpus_irq_work; 868 struct irq_work resched_irq_work; 869 }; 870 #endif /* CONFIG_SCHED_CLASS_EXT */ 871 872 static inline int rt_bandwidth_enabled(void) 873 { 874 return sysctl_sched_rt_runtime >= 0; 875 } 876 877 /* RT IPI pull logic requires IRQ_WORK */ 878 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP) 879 # define HAVE_RT_PUSH_IPI 880 #endif 881 882 /* Real-Time classes' related field in a runqueue: */ 883 struct rt_rq { 884 struct rt_prio_array active; 885 unsigned int rt_nr_running; 886 unsigned int rr_nr_running; 887 struct { 888 int curr; /* highest queued rt task prio */ 889 int next; /* next highest */ 890 } highest_prio; 891 bool overloaded; 892 struct plist_head pushable_tasks; 893 894 int rt_queued; 895 896 #ifdef CONFIG_RT_GROUP_SCHED 897 int rt_throttled; 898 u64 rt_time; /* consumed RT time, goes up in update_curr_rt */ 899 u64 rt_runtime; /* allotted RT time, "slice" from rt_bandwidth, RT sharing/balancing */ 900 /* Nests inside the rq lock: */ 901 raw_spinlock_t rt_runtime_lock; 902 903 unsigned int rt_nr_boosted; 904 905 struct rq *rq; /* this is always top-level rq, cache? */ 906 #endif 907 #ifdef CONFIG_CGROUP_SCHED 908 struct task_group *tg; /* this tg has "this" rt_rq on given CPU for runnable entities */ 909 #endif 910 }; 911 912 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq) 913 { 914 return rt_rq->rt_queued && rt_rq->rt_nr_running; 915 } 916 917 /* Deadline class' related fields in a runqueue */ 918 struct dl_rq { 919 /* runqueue is an rbtree, ordered by deadline */ 920 struct rb_root_cached root; 921 922 unsigned int dl_nr_running; 923 924 /* 925 * Deadline values of the currently executing and the 926 * earliest ready task on this rq. Caching these facilitates 927 * the decision whether or not a ready but not running task 928 * should migrate somewhere else. 929 */ 930 struct { 931 u64 curr; 932 u64 next; 933 } earliest_dl; 934 935 bool overloaded; 936 937 struct sched_dl_entity *curr; 938 /* 939 * Tasks on this rq that can be pushed away. They are kept in 940 * an rb-tree, ordered by tasks' deadlines, with caching 941 * of the leftmost (earliest deadline) element. 942 */ 943 struct rb_root_cached pushable_dl_tasks_root; 944 945 /* 946 * "Active utilization" for this runqueue: increased when a 947 * task wakes up (becomes TASK_RUNNING) and decreased when a 948 * task blocks 949 */ 950 u64 running_bw; 951 952 /* 953 * Utilization of the tasks "assigned" to this runqueue (including 954 * the tasks that are in runqueue and the tasks that executed on this 955 * CPU and blocked). Increased when a task moves to this runqueue, and 956 * decreased when the task moves away (migrates, changes scheduling 957 * policy, or terminates). 958 * This is needed to compute the "inactive utilization" for the 959 * runqueue (inactive utilization = this_bw - running_bw). 960 */ 961 u64 this_bw; 962 u64 extra_bw; 963 964 /* 965 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM 966 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB). 967 */ 968 u64 max_bw; 969 970 /* 971 * Inverse of the fraction of CPU utilization that can be reclaimed 972 * by the GRUB algorithm. 973 */ 974 u64 bw_ratio; 975 }; 976 977 #ifdef CONFIG_FAIR_GROUP_SCHED 978 /* Check whether a task group is root tg */ 979 #define is_root_task_group(tg) ((tg) == &root_task_group) 980 /* An entity is a task if it doesn't "own" a runqueue */ 981 #define entity_is_task(se) (!se->my_q) 982 983 static inline void se_update_runnable(struct sched_entity *se) 984 { 985 if (!entity_is_task(se)) 986 se->runnable_weight = se->my_q->h_nr_runnable; 987 } 988 989 static inline long se_runnable(struct sched_entity *se) 990 { 991 if (se->sched_delayed) 992 return false; 993 994 if (entity_is_task(se)) 995 return !!se->on_rq; 996 else 997 return se->runnable_weight; 998 } 999 1000 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 1001 1002 #define entity_is_task(se) 1 1003 1004 static inline void se_update_runnable(struct sched_entity *se) { } 1005 1006 static inline long se_runnable(struct sched_entity *se) 1007 { 1008 if (se->sched_delayed) 1009 return false; 1010 1011 return !!se->on_rq; 1012 } 1013 1014 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 1015 1016 /* 1017 * XXX we want to get rid of these helpers and use the full load resolution. 1018 */ 1019 static inline long se_weight(struct sched_entity *se) 1020 { 1021 return scale_load_down(se->load.weight); 1022 } 1023 1024 1025 static inline bool sched_asym_prefer(int a, int b) 1026 { 1027 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b); 1028 } 1029 1030 struct perf_domain { 1031 struct em_perf_domain *em_pd; 1032 struct perf_domain *next; 1033 struct rcu_head rcu; 1034 }; 1035 1036 /* 1037 * We add the notion of a root-domain which will be used to define per-domain 1038 * variables. Each exclusive cpuset essentially defines an island domain by 1039 * fully partitioning the member CPUs from any other cpuset. Whenever a new 1040 * exclusive cpuset is created, we also create and attach a new root-domain 1041 * object. 1042 * 1043 */ 1044 struct root_domain { 1045 atomic_t refcount; 1046 atomic_t rto_count; 1047 struct rcu_head rcu; 1048 cpumask_var_t span; 1049 cpumask_var_t online; 1050 1051 /* 1052 * Indicate pullable load on at least one CPU, e.g: 1053 * - More than one runnable task 1054 * - Running task is misfit 1055 */ 1056 bool overloaded; 1057 1058 /* Indicate one or more CPUs over-utilized (tipping point) */ 1059 bool overutilized; 1060 1061 /* 1062 * The bit corresponding to a CPU gets set here if such CPU has more 1063 * than one runnable -deadline task (as it is below for RT tasks). 1064 */ 1065 cpumask_var_t dlo_mask; 1066 atomic_t dlo_count; 1067 struct dl_bw dl_bw; 1068 struct cpudl cpudl; 1069 1070 /* 1071 * Indicate whether a root_domain's dl_bw has been checked or 1072 * updated. It's monotonously increasing value. 1073 * 1074 * Also, some corner cases, like 'wrap around' is dangerous, but given 1075 * that u64 is 'big enough'. So that shouldn't be a concern. 1076 */ 1077 u64 visit_cookie; 1078 1079 #ifdef HAVE_RT_PUSH_IPI 1080 /* 1081 * For IPI pull requests, loop across the rto_mask. 1082 */ 1083 struct irq_work rto_push_work; 1084 raw_spinlock_t rto_lock; 1085 /* These are only updated and read within rto_lock */ 1086 int rto_loop; 1087 int rto_cpu; 1088 /* These atomics are updated outside of a lock */ 1089 atomic_t rto_loop_next; 1090 atomic_t rto_loop_start; 1091 #endif /* HAVE_RT_PUSH_IPI */ 1092 /* 1093 * The "RT overload" flag: it gets set if a CPU has more than 1094 * one runnable RT task. 1095 */ 1096 cpumask_var_t rto_mask; 1097 struct cpupri cpupri; 1098 1099 /* 1100 * NULL-terminated list of performance domains intersecting with the 1101 * CPUs of the rd. Protected by RCU. 1102 */ 1103 struct perf_domain __rcu *pd; 1104 }; 1105 1106 extern void init_defrootdomain(void); 1107 extern int sched_init_domains(const struct cpumask *cpu_map); 1108 extern void rq_attach_root(struct rq *rq, struct root_domain *rd); 1109 extern void sched_get_rd(struct root_domain *rd); 1110 extern void sched_put_rd(struct root_domain *rd); 1111 1112 static inline int get_rd_overloaded(struct root_domain *rd) 1113 { 1114 return READ_ONCE(rd->overloaded); 1115 } 1116 1117 static inline void set_rd_overloaded(struct root_domain *rd, int status) 1118 { 1119 if (get_rd_overloaded(rd) != status) 1120 WRITE_ONCE(rd->overloaded, status); 1121 } 1122 1123 #ifdef HAVE_RT_PUSH_IPI 1124 extern void rto_push_irq_work_func(struct irq_work *work); 1125 #endif 1126 1127 #ifdef CONFIG_UCLAMP_TASK 1128 /* 1129 * struct uclamp_bucket - Utilization clamp bucket 1130 * @value: utilization clamp value for tasks on this clamp bucket 1131 * @tasks: number of RUNNABLE tasks on this clamp bucket 1132 * 1133 * Keep track of how many tasks are RUNNABLE for a given utilization 1134 * clamp value. 1135 */ 1136 struct uclamp_bucket { 1137 unsigned long value : bits_per(SCHED_CAPACITY_SCALE); 1138 unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE); 1139 }; 1140 1141 /* 1142 * struct uclamp_rq - rq's utilization clamp 1143 * @value: currently active clamp values for a rq 1144 * @bucket: utilization clamp buckets affecting a rq 1145 * 1146 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values. 1147 * A clamp value is affecting a rq when there is at least one task RUNNABLE 1148 * (or actually running) with that value. 1149 * 1150 * There are up to UCLAMP_CNT possible different clamp values, currently there 1151 * are only two: minimum utilization and maximum utilization. 1152 * 1153 * All utilization clamping values are MAX aggregated, since: 1154 * - for util_min: we want to run the CPU at least at the max of the minimum 1155 * utilization required by its currently RUNNABLE tasks. 1156 * - for util_max: we want to allow the CPU to run up to the max of the 1157 * maximum utilization allowed by its currently RUNNABLE tasks. 1158 * 1159 * Since on each system we expect only a limited number of different 1160 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track 1161 * the metrics required to compute all the per-rq utilization clamp values. 1162 */ 1163 struct uclamp_rq { 1164 unsigned int value; 1165 struct uclamp_bucket bucket[UCLAMP_BUCKETS]; 1166 }; 1167 1168 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used); 1169 #endif /* CONFIG_UCLAMP_TASK */ 1170 1171 /* 1172 * This is the main, per-CPU runqueue data structure. 1173 * 1174 * Locking rule: those places that want to lock multiple runqueues 1175 * (such as the load balancing or the thread migration code), lock 1176 * acquire operations must be ordered by ascending &runqueue. 1177 */ 1178 struct rq { 1179 /* 1180 * The following members are loaded together, without holding the 1181 * rq->lock, in an extremely hot loop in update_sg_lb_stats() 1182 * (called from pick_next_task()). To reduce cache pollution from 1183 * this operation, they are placed together on this dedicated cache 1184 * line. Even though some of them are frequently modified, they are 1185 * loaded much more frequently than they are stored. 1186 */ 1187 unsigned int nr_running; 1188 #ifdef CONFIG_NUMA_BALANCING 1189 unsigned int nr_numa_running; 1190 unsigned int nr_preferred_running; 1191 #endif 1192 unsigned int ttwu_pending; 1193 unsigned long cpu_capacity; 1194 #ifdef CONFIG_SCHED_PROXY_EXEC 1195 struct task_struct __rcu *donor; /* Scheduling context */ 1196 struct task_struct __rcu *curr; /* Execution context */ 1197 #else 1198 union { 1199 struct task_struct __rcu *donor; /* Scheduler context */ 1200 struct task_struct __rcu *curr; /* Execution context */ 1201 }; 1202 #endif 1203 struct task_struct *idle; 1204 /* padding left here deliberately */ 1205 1206 /* 1207 * The next cacheline holds the (hot) runqueue lock, as well as 1208 * some other less performance-critical fields. 1209 */ 1210 u64 nr_switches ____cacheline_aligned; 1211 1212 /* runqueue lock: */ 1213 raw_spinlock_t __lock; 1214 1215 #ifdef CONFIG_NO_HZ_COMMON 1216 unsigned int nohz_tick_stopped; 1217 atomic_t nohz_flags; 1218 unsigned int has_blocked_load; 1219 unsigned long last_blocked_load_update_tick; 1220 call_single_data_t nohz_csd; 1221 #endif /* CONFIG_NO_HZ_COMMON */ 1222 1223 #ifdef CONFIG_UCLAMP_TASK 1224 /* Utilization clamp values based on CPU's RUNNABLE tasks */ 1225 struct uclamp_rq uclamp[UCLAMP_CNT] ____cacheline_aligned; 1226 unsigned int uclamp_flags; 1227 #define UCLAMP_FLAG_IDLE 0x01 1228 #endif 1229 1230 struct cfs_rq cfs; 1231 struct rt_rq rt; 1232 struct dl_rq dl; 1233 #ifdef CONFIG_SCHED_CLASS_EXT 1234 struct scx_rq scx; 1235 struct sched_dl_entity ext_server; 1236 #endif 1237 #ifdef CONFIG_SCHED_CACHE 1238 raw_spinlock_t cpu_epoch_lock ____cacheline_aligned; 1239 u64 cpu_runtime; 1240 unsigned long cpu_epoch; 1241 unsigned long cpu_epoch_next; 1242 #endif 1243 1244 struct sched_dl_entity fair_server; 1245 1246 #ifdef CONFIG_FAIR_GROUP_SCHED 1247 /* list of leaf cfs_rq on this CPU: */ 1248 struct list_head leaf_cfs_rq_list; 1249 struct list_head *tmp_alone_branch; 1250 #endif /* CONFIG_FAIR_GROUP_SCHED */ 1251 1252 #ifdef CONFIG_NUMA_BALANCING 1253 unsigned int numa_migrate_on; 1254 #endif 1255 1256 #ifdef CONFIG_SCHED_CACHE 1257 unsigned int nr_pref_llc_running; 1258 unsigned int nr_llc_running; 1259 #endif 1260 1261 /* 1262 * This is part of a global counter where only the total sum 1263 * over all CPUs matters. A task can increase this counter on 1264 * one CPU and if it got migrated afterwards it may decrease 1265 * it on another CPU. Always updated under the runqueue lock: 1266 */ 1267 unsigned long nr_uninterruptible; 1268 1269 struct sched_dl_entity *dl_server; 1270 struct task_struct *stop; 1271 const struct sched_class *next_class; 1272 unsigned long next_balance; 1273 struct mm_struct *prev_mm; 1274 1275 /* 1276 * The following fields of clock data are frequently referenced 1277 * and updated together, and should go on their own cache line. 1278 */ 1279 u64 clock_task ____cacheline_aligned; 1280 u64 clock_pelt; 1281 u64 clock; 1282 unsigned long lost_idle_time; 1283 unsigned int clock_update_flags; 1284 u64 clock_pelt_idle; 1285 u64 clock_idle; 1286 1287 #ifndef CONFIG_64BIT 1288 u64 clock_pelt_idle_copy; 1289 u64 clock_idle_copy; 1290 #endif 1291 1292 u64 last_seen_need_resched_ns; 1293 int ticks_without_resched; 1294 1295 #ifdef CONFIG_MEMBARRIER 1296 int membarrier_state; 1297 #endif 1298 1299 struct root_domain *rd; 1300 struct sched_domain __rcu *sd; 1301 1302 struct balance_callback *balance_callback; 1303 1304 unsigned char nohz_idle_balance; 1305 unsigned char idle_balance; 1306 1307 unsigned long misfit_task_load; 1308 1309 /* For active balancing */ 1310 int active_balance; 1311 int push_cpu; 1312 struct cpu_stop_work active_balance_work; 1313 1314 /* CPU of this runqueue: */ 1315 int cpu; 1316 int online; 1317 1318 struct list_head cfs_tasks; 1319 1320 struct sched_avg avg_rt; 1321 struct sched_avg avg_dl; 1322 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 1323 struct sched_avg avg_irq; 1324 #endif 1325 #ifdef CONFIG_SCHED_HW_PRESSURE 1326 struct sched_avg avg_hw; 1327 #endif 1328 u64 idle_stamp; 1329 u64 avg_idle; 1330 1331 /* This is used to determine avg_idle's max value */ 1332 u64 max_idle_balance_cost; 1333 1334 #ifdef CONFIG_HOTPLUG_CPU 1335 struct rcuwait hotplug_wait; 1336 #endif 1337 1338 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 1339 u64 prev_irq_time; 1340 u64 psi_irq_time; 1341 #endif 1342 #ifdef CONFIG_PARAVIRT 1343 u64 prev_steal_time; 1344 #endif 1345 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING 1346 u64 prev_steal_time_rq; 1347 #endif 1348 #ifdef CONFIG_PREFERRED_CPU 1349 bool npc_push_work_pending; 1350 #endif 1351 1352 /* calc_load related fields */ 1353 unsigned long calc_load_update; 1354 long calc_load_active; 1355 1356 #ifdef CONFIG_SCHED_HRTICK 1357 call_single_data_t hrtick_csd; 1358 struct hrtimer hrtick_timer; 1359 ktime_t hrtick_time; 1360 ktime_t hrtick_delay; 1361 unsigned int hrtick_sched; 1362 #endif 1363 1364 #ifdef CONFIG_SCHEDSTATS 1365 /* latency stats */ 1366 struct sched_info rq_sched_info; 1367 unsigned long long rq_cpu_time; 1368 1369 /* sys_sched_yield() stats */ 1370 unsigned int yld_count; 1371 1372 /* schedule() stats */ 1373 unsigned int sched_count; 1374 unsigned int sched_goidle; 1375 1376 /* try_to_wake_up() stats */ 1377 unsigned int ttwu_count; 1378 unsigned int ttwu_local; 1379 #endif 1380 1381 #ifdef CONFIG_CPU_IDLE 1382 /* Must be inspected within a RCU lock section */ 1383 struct cpuidle_state *idle_state; 1384 #endif 1385 1386 unsigned int nr_pinned; 1387 unsigned int push_busy; 1388 struct cpu_stop_work push_work; 1389 1390 #ifdef CONFIG_SCHED_CORE 1391 /* per rq */ 1392 struct rq *core; 1393 struct task_struct *core_pick; 1394 struct sched_dl_entity *core_dl_server; 1395 unsigned int core_enabled; 1396 struct rb_root core_tree; 1397 1398 /* shared state -- careful with sched_core_cpu_deactivate() */ 1399 unsigned int core_task_seq; 1400 unsigned int core_pick_seq; 1401 unsigned long core_cookie; 1402 unsigned int core_forceidle_count; 1403 unsigned int core_forceidle_seq; 1404 unsigned int core_forceidle_occupation; 1405 u64 core_forceidle_start; 1406 unsigned int core_pick_in_flight; 1407 #endif /* CONFIG_SCHED_CORE */ 1408 1409 /* Scratch cpumask to be temporarily used under rq_lock */ 1410 cpumask_var_t scratch_mask; 1411 1412 #ifdef CONFIG_CFS_BANDWIDTH 1413 call_single_data_t cfsb_csd; 1414 struct list_head cfsb_csd_list; 1415 #endif 1416 1417 atomic_t nr_iowait; 1418 } __no_randomize_layout; 1419 1420 #ifdef CONFIG_FAIR_GROUP_SCHED 1421 1422 /* CPU runqueue to which this cfs_rq is attached */ 1423 static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1424 { 1425 return cfs_rq->rq; 1426 } 1427 1428 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 1429 1430 static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1431 { 1432 return container_of(cfs_rq, struct rq, cfs); 1433 } 1434 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 1435 1436 static inline int cpu_of(struct rq *rq) 1437 { 1438 return rq->cpu; 1439 } 1440 1441 #define MDF_PUSH 0x01 1442 1443 static inline bool is_migration_disabled(struct task_struct *p) 1444 { 1445 return p->migration_disabled; 1446 } 1447 1448 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); 1449 DECLARE_PER_CPU(struct rnd_state, sched_rnd_state); 1450 1451 static inline u32 sched_rng(void) 1452 { 1453 return prandom_u32_state(this_cpu_ptr(&sched_rnd_state)); 1454 } 1455 1456 static __always_inline struct rq *__this_rq(void) 1457 { 1458 return this_cpu_ptr(&runqueues); 1459 } 1460 1461 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) 1462 #define this_rq() __this_rq() 1463 #define task_rq(p) cpu_rq(task_cpu(p)) 1464 #define cpu_curr(cpu) (cpu_rq(cpu)->curr) 1465 #define raw_rq() raw_cpu_ptr(&runqueues) 1466 1467 static inline bool idle_rq(struct rq *rq) 1468 { 1469 return rq->curr == rq->idle && !rq->nr_running && !rq->ttwu_pending; 1470 } 1471 1472 /** 1473 * available_idle_cpu - is a given CPU idle for enqueuing work. 1474 * @cpu: the CPU in question. 1475 * 1476 * Return: 1 if the CPU is currently idle. 0 otherwise. 1477 */ 1478 static inline bool available_idle_cpu(int cpu) 1479 { 1480 if (!idle_rq(cpu_rq(cpu))) 1481 return 0; 1482 1483 if (vcpu_is_preempted(cpu)) 1484 return 0; 1485 1486 return 1; 1487 } 1488 1489 #ifdef CONFIG_SCHED_PROXY_EXEC 1490 static inline void rq_set_donor(struct rq *rq, struct task_struct *t) 1491 { 1492 rcu_assign_pointer(rq->donor, t); 1493 } 1494 #else 1495 static inline void rq_set_donor(struct rq *rq, struct task_struct *t) 1496 { 1497 /* Do nothing */ 1498 } 1499 #endif 1500 1501 #ifdef CONFIG_SCHED_CORE 1502 static inline struct cpumask *sched_group_span(struct sched_group *sg); 1503 1504 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled); 1505 1506 static inline bool sched_core_enabled(struct rq *rq) 1507 { 1508 return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled; 1509 } 1510 1511 static inline bool sched_core_disabled(void) 1512 { 1513 return !static_branch_unlikely(&__sched_core_enabled); 1514 } 1515 1516 /* 1517 * Be careful with this function; not for general use. The return value isn't 1518 * stable unless you actually hold a relevant rq->__lock. 1519 */ 1520 static inline raw_spinlock_t *rq_lockp(struct rq *rq) 1521 { 1522 if (sched_core_enabled(rq)) 1523 return &rq->core->__lock; 1524 1525 return &rq->__lock; 1526 } 1527 1528 static inline raw_spinlock_t *__rq_lockp(struct rq *rq) 1529 __returns_ctx_lock(rq_lockp(rq)) /* alias them */ 1530 { 1531 if (rq->core_enabled) 1532 return &rq->core->__lock; 1533 1534 return &rq->__lock; 1535 } 1536 1537 extern bool 1538 cfs_prio_less(const struct task_struct *a, const struct task_struct *b, bool fi); 1539 1540 extern void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi); 1541 1542 /* 1543 * Helpers to check if the CPU's core cookie matches with the task's cookie 1544 * when core scheduling is enabled. 1545 * A special case is that the task's cookie always matches with CPU's core 1546 * cookie if the CPU is in an idle core. 1547 */ 1548 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p) 1549 { 1550 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1551 if (!sched_core_enabled(rq)) 1552 return true; 1553 1554 return rq->core->core_cookie == p->core_cookie; 1555 } 1556 1557 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) 1558 { 1559 bool idle_core = true; 1560 int cpu; 1561 1562 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1563 if (!sched_core_enabled(rq)) 1564 return true; 1565 1566 if (rq->core->core_cookie == p->core_cookie) 1567 return true; 1568 1569 for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) { 1570 if (!available_idle_cpu(cpu)) { 1571 idle_core = false; 1572 break; 1573 } 1574 } 1575 1576 /* 1577 * A CPU in an idle core is always the best choice for tasks with 1578 * cookies. 1579 */ 1580 return idle_core; 1581 } 1582 1583 static inline bool sched_group_cookie_match(struct rq *rq, 1584 struct task_struct *p, 1585 struct sched_group *group) 1586 { 1587 int cpu; 1588 1589 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1590 if (!sched_core_enabled(rq)) 1591 return true; 1592 1593 for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) { 1594 if (sched_core_cookie_match(cpu_rq(cpu), p)) 1595 return true; 1596 } 1597 return false; 1598 } 1599 1600 static inline bool sched_core_enqueued(struct task_struct *p) 1601 { 1602 return !RB_EMPTY_NODE(&p->core_node); 1603 } 1604 1605 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p); 1606 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags); 1607 1608 extern void sched_core_get(void); 1609 extern void sched_core_put(void); 1610 1611 static inline bool task_has_sched_core(struct task_struct *p) 1612 { 1613 if (sched_core_disabled()) 1614 return false; 1615 1616 return !!p->core_cookie; 1617 } 1618 1619 #else /* !CONFIG_SCHED_CORE: */ 1620 1621 static inline bool sched_core_enabled(struct rq *rq) 1622 { 1623 return false; 1624 } 1625 1626 static inline bool sched_core_disabled(void) 1627 { 1628 return true; 1629 } 1630 1631 static inline raw_spinlock_t *rq_lockp(struct rq *rq) 1632 { 1633 return &rq->__lock; 1634 } 1635 1636 static inline raw_spinlock_t *__rq_lockp(struct rq *rq) 1637 __returns_ctx_lock(rq_lockp(rq)) /* alias them */ 1638 { 1639 return &rq->__lock; 1640 } 1641 1642 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p) 1643 { 1644 return true; 1645 } 1646 1647 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) 1648 { 1649 return true; 1650 } 1651 1652 static inline bool sched_group_cookie_match(struct rq *rq, 1653 struct task_struct *p, 1654 struct sched_group *group) 1655 { 1656 return true; 1657 } 1658 1659 static inline bool task_has_sched_core(struct task_struct *p) 1660 { 1661 return false; 1662 } 1663 1664 #endif /* !CONFIG_SCHED_CORE */ 1665 1666 #ifdef CONFIG_RT_GROUP_SCHED 1667 # ifdef CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED 1668 DECLARE_STATIC_KEY_FALSE(rt_group_sched); 1669 static inline bool rt_group_sched_enabled(void) 1670 { 1671 return static_branch_unlikely(&rt_group_sched); 1672 } 1673 # else /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED: */ 1674 DECLARE_STATIC_KEY_TRUE(rt_group_sched); 1675 static inline bool rt_group_sched_enabled(void) 1676 { 1677 return static_branch_likely(&rt_group_sched); 1678 } 1679 # endif /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED */ 1680 #else /* !CONFIG_RT_GROUP_SCHED: */ 1681 # define rt_group_sched_enabled() false 1682 #endif /* !CONFIG_RT_GROUP_SCHED */ 1683 1684 static inline void lockdep_assert_rq_held(struct rq *rq) 1685 __assumes_ctx_lock(__rq_lockp(rq)) 1686 { 1687 lockdep_assert_held(__rq_lockp(rq)); 1688 } 1689 1690 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass) 1691 __acquires(__rq_lockp(rq)); 1692 1693 extern bool raw_spin_rq_trylock(struct rq *rq) 1694 __cond_acquires(true, __rq_lockp(rq)); 1695 1696 static inline void raw_spin_rq_lock(struct rq *rq) 1697 __acquires(__rq_lockp(rq)) 1698 { 1699 raw_spin_rq_lock_nested(rq, 0); 1700 } 1701 1702 static inline void raw_spin_rq_unlock(struct rq *rq) 1703 __releases(__rq_lockp(rq)) 1704 { 1705 raw_spin_unlock(rq_lockp(rq)); 1706 } 1707 1708 static inline void raw_spin_rq_lock_irq(struct rq *rq) 1709 __acquires(__rq_lockp(rq)) 1710 { 1711 local_irq_disable(); 1712 raw_spin_rq_lock(rq); 1713 } 1714 1715 static inline void raw_spin_rq_unlock_irq(struct rq *rq) 1716 __releases(__rq_lockp(rq)) 1717 { 1718 raw_spin_rq_unlock(rq); 1719 local_irq_enable(); 1720 } 1721 1722 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq) 1723 __acquires(__rq_lockp(rq)) 1724 { 1725 unsigned long flags; 1726 1727 local_irq_save(flags); 1728 raw_spin_rq_lock(rq); 1729 1730 return flags; 1731 } 1732 1733 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags) 1734 __releases(__rq_lockp(rq)) 1735 { 1736 raw_spin_rq_unlock(rq); 1737 local_irq_restore(flags); 1738 } 1739 1740 #define raw_spin_rq_lock_irqsave(rq, flags) \ 1741 do { \ 1742 flags = _raw_spin_rq_lock_irqsave(rq); \ 1743 } while (0) 1744 1745 extern void __update_idle_core(struct rq *rq); 1746 1747 static inline void update_idle_core(struct rq *rq) 1748 { 1749 if (sched_smt_active()) 1750 __update_idle_core(rq); 1751 } 1752 1753 #ifdef CONFIG_FAIR_GROUP_SCHED 1754 static inline struct task_struct *task_of(struct sched_entity *se) 1755 { 1756 WARN_ON_ONCE(!entity_is_task(se)); 1757 return container_of(se, struct task_struct, se); 1758 } 1759 1760 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p) 1761 { 1762 return p->se.cfs_rq; 1763 } 1764 1765 /* runqueue on which this entity is (to be) queued */ 1766 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se) 1767 { 1768 return se->cfs_rq; 1769 } 1770 1771 /* runqueue "owned" by this group */ 1772 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) 1773 { 1774 return grp->my_q; 1775 } 1776 1777 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 1778 1779 #define task_of(_se) container_of(_se, struct task_struct, se) 1780 1781 static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p) 1782 { 1783 return &task_rq(p)->cfs; 1784 } 1785 1786 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se) 1787 { 1788 const struct task_struct *p = task_of(se); 1789 struct rq *rq = task_rq(p); 1790 1791 return &rq->cfs; 1792 } 1793 1794 /* runqueue "owned" by this group */ 1795 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) 1796 { 1797 return NULL; 1798 } 1799 1800 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 1801 1802 extern void update_rq_avg_idle(struct rq *rq); 1803 extern void update_rq_clock(struct rq *rq); 1804 1805 /* 1806 * rq::clock_update_flags bits 1807 * 1808 * %RQCF_REQ_SKIP - will request skipping of clock update on the next 1809 * call to __schedule(). This is an optimisation to avoid 1810 * neighbouring rq clock updates. 1811 * 1812 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is 1813 * in effect and calls to update_rq_clock() are being ignored. 1814 * 1815 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been 1816 * made to update_rq_clock() since the last time rq::lock was pinned. 1817 * 1818 * If inside of __schedule(), clock_update_flags will have been 1819 * shifted left (a left shift is a cheap operation for the fast path 1820 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use, 1821 * 1822 * if (rq-clock_update_flags >= RQCF_UPDATED) 1823 * 1824 * to check if %RQCF_UPDATED is set. It'll never be shifted more than 1825 * one position though, because the next rq_unpin_lock() will shift it 1826 * back. 1827 */ 1828 #define RQCF_REQ_SKIP 0x01 1829 #define RQCF_ACT_SKIP 0x02 1830 #define RQCF_UPDATED 0x04 1831 1832 static inline void assert_clock_updated(struct rq *rq) 1833 { 1834 /* 1835 * The only reason for not seeing a clock update since the 1836 * last rq_pin_lock() is if we're currently skipping updates. 1837 */ 1838 WARN_ON_ONCE(rq->clock_update_flags < RQCF_ACT_SKIP); 1839 } 1840 1841 static inline u64 rq_clock(struct rq *rq) 1842 { 1843 lockdep_assert_rq_held(rq); 1844 assert_clock_updated(rq); 1845 1846 return rq->clock; 1847 } 1848 1849 static inline u64 rq_clock_task(struct rq *rq) 1850 { 1851 lockdep_assert_rq_held(rq); 1852 assert_clock_updated(rq); 1853 1854 return rq->clock_task; 1855 } 1856 1857 static inline void rq_clock_skip_update(struct rq *rq) 1858 { 1859 lockdep_assert_rq_held(rq); 1860 rq->clock_update_flags |= RQCF_REQ_SKIP; 1861 } 1862 1863 /* 1864 * See rt task throttling, which is the only time a skip 1865 * request is canceled. 1866 */ 1867 static inline void rq_clock_cancel_skipupdate(struct rq *rq) 1868 { 1869 lockdep_assert_rq_held(rq); 1870 rq->clock_update_flags &= ~RQCF_REQ_SKIP; 1871 } 1872 1873 /* 1874 * During cpu offlining and rq wide unthrottling, we can trigger 1875 * an update_rq_clock() for several cfs and rt runqueues (Typically 1876 * when using list_for_each_entry_*) 1877 * rq_clock_start_loop_update() can be called after updating the clock 1878 * once and before iterating over the list to prevent multiple update. 1879 * After the iterative traversal, we need to call rq_clock_stop_loop_update() 1880 * to clear RQCF_ACT_SKIP of rq->clock_update_flags. 1881 */ 1882 static inline void rq_clock_start_loop_update(struct rq *rq) 1883 { 1884 lockdep_assert_rq_held(rq); 1885 WARN_ON_ONCE(rq->clock_update_flags & RQCF_ACT_SKIP); 1886 rq->clock_update_flags |= RQCF_ACT_SKIP; 1887 } 1888 1889 static inline void rq_clock_stop_loop_update(struct rq *rq) 1890 { 1891 lockdep_assert_rq_held(rq); 1892 rq->clock_update_flags &= ~RQCF_ACT_SKIP; 1893 } 1894 1895 struct rq_flags { 1896 unsigned long flags; 1897 struct pin_cookie cookie; 1898 /* 1899 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the 1900 * current pin context is stashed here in case it needs to be 1901 * restored in rq_repin_lock(). 1902 */ 1903 unsigned int clock_update_flags; 1904 }; 1905 1906 extern struct balance_callback balance_push_callback; 1907 1908 #ifdef CONFIG_SCHED_CLASS_EXT 1909 extern const struct sched_class ext_sched_class; 1910 1911 DECLARE_STATIC_KEY_FALSE(__scx_enabled); /* SCX BPF scheduler loaded */ 1912 DECLARE_STATIC_KEY_FALSE(__scx_switched_all); /* all fair class tasks on SCX */ 1913 1914 #define scx_enabled() static_branch_unlikely(&__scx_enabled) 1915 #define scx_switched_all() static_branch_unlikely(&__scx_switched_all) 1916 1917 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) 1918 { 1919 if (!scx_enabled()) 1920 return; 1921 WRITE_ONCE(rq->scx.clock, clock); 1922 smp_store_release(&rq->scx.flags, rq->scx.flags | SCX_RQ_CLK_VALID); 1923 } 1924 1925 static inline void scx_rq_clock_invalidate(struct rq *rq) 1926 { 1927 if (!scx_enabled()) 1928 return; 1929 WRITE_ONCE(rq->scx.flags, rq->scx.flags & ~SCX_RQ_CLK_VALID); 1930 } 1931 1932 #else /* !CONFIG_SCHED_CLASS_EXT: */ 1933 #define scx_enabled() false 1934 #define scx_switched_all() false 1935 1936 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) {} 1937 static inline void scx_rq_clock_invalidate(struct rq *rq) {} 1938 #endif /* !CONFIG_SCHED_CLASS_EXT */ 1939 1940 static inline void assert_balance_callbacks_empty(struct rq *rq) 1941 { 1942 WARN_ON_ONCE(IS_ENABLED(CONFIG_PROVE_LOCKING) && 1943 rq->balance_callback && 1944 rq->balance_callback != &balance_push_callback); 1945 } 1946 1947 /* 1948 * Lockdep annotation that avoids accidental unlocks; it's like a 1949 * sticky/continuous lockdep_assert_held(). 1950 * 1951 * This avoids code that has access to 'struct rq *rq' (basically everything in 1952 * the scheduler) from accidentally unlocking the rq if they do not also have a 1953 * copy of the (on-stack) 'struct rq_flags rf'. 1954 * 1955 * Also see Documentation/locking/lockdep-design.rst. 1956 */ 1957 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf) 1958 { 1959 rf->cookie = lockdep_pin_lock(__rq_lockp(rq)); 1960 1961 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 1962 rf->clock_update_flags = 0; 1963 assert_balance_callbacks_empty(rq); 1964 } 1965 1966 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf) 1967 { 1968 if (rq->clock_update_flags > RQCF_ACT_SKIP) 1969 rf->clock_update_flags = RQCF_UPDATED; 1970 1971 scx_rq_clock_invalidate(rq); 1972 lockdep_unpin_lock(__rq_lockp(rq), rf->cookie); 1973 } 1974 1975 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf) 1976 { 1977 lockdep_repin_lock(__rq_lockp(rq), rf->cookie); 1978 1979 /* 1980 * Restore the value we stashed in @rf for this pin context. 1981 */ 1982 rq->clock_update_flags |= rf->clock_update_flags; 1983 } 1984 1985 #define __task_rq_lock(...) __acquire_ret(___task_rq_lock(__VA_ARGS__), __rq_lockp(__ret)) 1986 extern struct rq *___task_rq_lock(struct task_struct *p, struct rq_flags *rf) __acquires_ret; 1987 1988 #define task_rq_lock(...) __acquire_ret(_task_rq_lock(__VA_ARGS__), __rq_lockp(__ret)) 1989 extern struct rq *_task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1990 __acquires(&p->pi_lock) __acquires_ret; 1991 1992 static inline void 1993 __task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) 1994 __releases(__rq_lockp(rq)) 1995 { 1996 rq_unpin_lock(rq, rf); 1997 raw_spin_rq_unlock(rq); 1998 } 1999 2000 static inline void 2001 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) 2002 __releases(__rq_lockp(rq), &p->pi_lock) 2003 { 2004 __task_rq_unlock(rq, p, rf); 2005 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); 2006 } 2007 2008 DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct, 2009 _T->rq = task_rq_lock(_T->lock, &_T->rf), 2010 task_rq_unlock(_T->rq, _T->lock, &_T->rf), 2011 struct rq *rq; struct rq_flags rf) 2012 DECLARE_LOCK_GUARD_1_ATTRS(task_rq_lock, __acquires(_T->pi_lock), __releases((*(struct task_struct **)_T)->pi_lock)) 2013 #define class_task_rq_lock_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(task_rq_lock, _T) 2014 2015 DEFINE_LOCK_GUARD_1(__task_rq_lock, struct task_struct, 2016 _T->rq = __task_rq_lock(_T->lock, &_T->rf), 2017 __task_rq_unlock(_T->rq, _T->lock, &_T->rf), 2018 struct rq *rq; struct rq_flags rf) 2019 2020 static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) 2021 __acquires(__rq_lockp(rq)) 2022 { 2023 raw_spin_rq_lock_irqsave(rq, rf->flags); 2024 rq_pin_lock(rq, rf); 2025 } 2026 2027 static inline void rq_lock_irq(struct rq *rq, struct rq_flags *rf) 2028 __acquires(__rq_lockp(rq)) 2029 { 2030 raw_spin_rq_lock_irq(rq); 2031 rq_pin_lock(rq, rf); 2032 } 2033 2034 static inline void rq_lock(struct rq *rq, struct rq_flags *rf) 2035 __acquires(__rq_lockp(rq)) 2036 { 2037 raw_spin_rq_lock(rq); 2038 rq_pin_lock(rq, rf); 2039 } 2040 2041 static inline void rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf) 2042 __releases(__rq_lockp(rq)) 2043 { 2044 rq_unpin_lock(rq, rf); 2045 raw_spin_rq_unlock_irqrestore(rq, rf->flags); 2046 } 2047 2048 static inline void rq_unlock_irq(struct rq *rq, struct rq_flags *rf) 2049 __releases(__rq_lockp(rq)) 2050 { 2051 rq_unpin_lock(rq, rf); 2052 raw_spin_rq_unlock_irq(rq); 2053 } 2054 2055 static inline void rq_unlock(struct rq *rq, struct rq_flags *rf) 2056 __releases(__rq_lockp(rq)) 2057 { 2058 rq_unpin_lock(rq, rf); 2059 raw_spin_rq_unlock(rq); 2060 } 2061 2062 DEFINE_LOCK_GUARD_1(rq_lock, struct rq, 2063 rq_lock(_T->lock, &_T->rf), 2064 rq_unlock(_T->lock, &_T->rf), 2065 struct rq_flags rf) 2066 2067 DECLARE_LOCK_GUARD_1_ATTRS(rq_lock, __acquires(__rq_lockp(_T)), 2068 __releases(__rq_lockp(*(struct rq **)_T))); 2069 #define class_rq_lock_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock, _T) 2070 2071 DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq, 2072 rq_lock_irq(_T->lock, &_T->rf), 2073 rq_unlock_irq(_T->lock, &_T->rf), 2074 struct rq_flags rf) 2075 2076 DECLARE_LOCK_GUARD_1_ATTRS(rq_lock_irq, __acquires(__rq_lockp(_T)), 2077 __releases(__rq_lockp(*(struct rq **)_T))); 2078 #define class_rq_lock_irq_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock_irq, _T) 2079 2080 DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq, 2081 rq_lock_irqsave(_T->lock, &_T->rf), 2082 rq_unlock_irqrestore(_T->lock, &_T->rf), 2083 struct rq_flags rf) 2084 2085 DECLARE_LOCK_GUARD_1_ATTRS(rq_lock_irqsave, __acquires(__rq_lockp(_T)), 2086 __releases(__rq_lockp(*(struct rq **)_T))); 2087 #define class_rq_lock_irqsave_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock_irqsave, _T) 2088 2089 DEFINE_LOCK_GUARD_1(raw_spin_rq_lock_irqsave, struct rq, 2090 raw_spin_rq_lock_irqsave(_T->lock, _T->flags), 2091 raw_spin_rq_unlock_irqrestore(_T->lock, _T->flags), 2092 unsigned long flags) 2093 2094 DECLARE_LOCK_GUARD_1_ATTRS(raw_spin_rq_lock_irqsave, __acquires(__rq_lockp(_T)), 2095 __releases(__rq_lockp(*(struct rq **)_T))); 2096 #define class_raw_spin_rq_lock_irqsave_constructor(_T) \ 2097 WITH_LOCK_GUARD_1_ATTRS(raw_spin_rq_lock_irqsave, _T) 2098 2099 #define this_rq_lock_irq(...) __acquire_ret(_this_rq_lock_irq(__VA_ARGS__), __rq_lockp(__ret)) 2100 static inline struct rq *_this_rq_lock_irq(struct rq_flags *rf) __acquires_ret 2101 { 2102 struct rq *rq; 2103 2104 local_irq_disable(); 2105 rq = this_rq(); 2106 rq_lock(rq, rf); 2107 2108 return rq; 2109 } 2110 2111 #ifdef CONFIG_NUMA 2112 2113 enum numa_topology_type { 2114 NUMA_DIRECT, 2115 NUMA_GLUELESS_MESH, 2116 NUMA_BACKPLANE, 2117 }; 2118 2119 extern enum numa_topology_type sched_numa_topology_type; 2120 extern int sched_max_numa_distance; 2121 extern bool find_numa_distance(int distance); 2122 extern void sched_init_numa(int offline_node); 2123 extern void sched_update_numa(int cpu, bool online); 2124 extern void sched_domains_numa_masks_set(unsigned int cpu); 2125 extern void sched_domains_numa_masks_clear(unsigned int cpu); 2126 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu); 2127 2128 #else /* !CONFIG_NUMA: */ 2129 2130 static inline void sched_init_numa(int offline_node) { } 2131 static inline void sched_update_numa(int cpu, bool online) { } 2132 static inline void sched_domains_numa_masks_set(unsigned int cpu) { } 2133 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { } 2134 2135 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu) 2136 { 2137 return nr_cpu_ids; 2138 } 2139 2140 #endif /* !CONFIG_NUMA */ 2141 2142 #ifdef CONFIG_NUMA_BALANCING 2143 2144 /* The regions in numa_faults array from task_struct */ 2145 enum numa_faults_stats { 2146 NUMA_MEM = 0, 2147 NUMA_CPU, 2148 NUMA_MEMBUF, 2149 NUMA_CPUBUF 2150 }; 2151 2152 extern void sched_setnuma(struct task_struct *p, int node); 2153 extern int migrate_task_to(struct task_struct *p, int cpu); 2154 extern int migrate_swap(struct task_struct *p, struct task_struct *t, 2155 int cpu, int scpu); 2156 extern void init_numa_balancing(u64 clone_flags, struct task_struct *p); 2157 2158 #else /* !CONFIG_NUMA_BALANCING: */ 2159 2160 static inline void 2161 init_numa_balancing(u64 clone_flags, struct task_struct *p) 2162 { 2163 } 2164 2165 #endif /* !CONFIG_NUMA_BALANCING */ 2166 2167 int task_llc(const struct task_struct *p); 2168 2169 static inline void 2170 queue_balance_callback(struct rq *rq, 2171 struct balance_callback *head, 2172 void (*func)(struct rq *rq)) 2173 { 2174 lockdep_assert_rq_held(rq); 2175 2176 /* 2177 * Don't (re)queue an already queued item; nor queue anything when 2178 * balance_push() is active, see the comment with 2179 * balance_push_callback. 2180 */ 2181 if (unlikely(head->next || rq->balance_callback == head || 2182 rq->balance_callback == &balance_push_callback)) 2183 return; 2184 2185 head->func = func; 2186 head->next = rq->balance_callback; 2187 rq->balance_callback = head; 2188 } 2189 2190 #define rcu_dereference_sched_domain(p) \ 2191 rcu_dereference_all_check((p), lockdep_is_held(&sched_domains_mutex)) 2192 2193 /* 2194 * The domain tree (rq->sd) is protected by RCU's quiescent state transition. 2195 * See destroy_sched_domains: call_rcu for details. 2196 * 2197 * The domain tree of any CPU may only be accessed from within 2198 * preempt-disabled sections. 2199 */ 2200 #define for_each_domain(cpu, __sd) \ 2201 for (__sd = rcu_dereference_sched_domain(cpu_rq(cpu)->sd); \ 2202 __sd; __sd = __sd->parent) 2203 2204 /* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */ 2205 #define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) | 2206 static const unsigned int SD_SHARED_CHILD_MASK = 2207 #include <linux/sched/sd_flags.h> 2208 0; 2209 #undef SD_FLAG 2210 2211 /** 2212 * highest_flag_domain - Return highest sched_domain containing flag. 2213 * @cpu: The CPU whose highest level of sched domain is to 2214 * be returned. 2215 * @flag: The flag to check for the highest sched_domain 2216 * for the given CPU. 2217 * 2218 * Returns the highest sched_domain of a CPU which contains @flag. If @flag has 2219 * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag. 2220 */ 2221 static inline struct sched_domain *highest_flag_domain(int cpu, int flag) 2222 { 2223 struct sched_domain *sd, *hsd = NULL; 2224 2225 for_each_domain(cpu, sd) { 2226 if (sd->flags & flag) { 2227 hsd = sd; 2228 continue; 2229 } 2230 2231 /* 2232 * Stop the search if @flag is known to be shared at lower 2233 * levels. It will not be found further up. 2234 */ 2235 if (flag & SD_SHARED_CHILD_MASK) 2236 break; 2237 } 2238 2239 return hsd; 2240 } 2241 2242 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) 2243 { 2244 struct sched_domain *sd; 2245 2246 for_each_domain(cpu, sd) { 2247 if (sd->flags & flag) 2248 break; 2249 } 2250 2251 return sd; 2252 } 2253 2254 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc); 2255 DECLARE_PER_CPU(int, sd_llc_size); 2256 DECLARE_PER_CPU(int, sd_llc_id); 2257 DECLARE_PER_CPU(int, sd_share_id); 2258 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared); 2259 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_balance_shared); 2260 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa); 2261 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing); 2262 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity); 2263 2264 extern struct static_key_false sched_asym_cpucapacity; 2265 extern struct static_key_false sched_cluster_active; 2266 2267 static __always_inline bool sched_asym_cpucap_active(void) 2268 { 2269 return static_branch_unlikely(&sched_asym_cpucapacity); 2270 } 2271 2272 struct sched_group_capacity { 2273 atomic_t ref; 2274 /* 2275 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity 2276 * for a single CPU. 2277 */ 2278 unsigned long capacity; 2279 unsigned long min_capacity; /* Min per-CPU capacity in group */ 2280 unsigned long max_capacity; /* Max per-CPU capacity in group */ 2281 unsigned long next_update; 2282 int imbalance; /* XXX unrelated to capacity but shared group state */ 2283 2284 int id; 2285 2286 unsigned long cpumask[]; /* Balance mask */ 2287 }; 2288 2289 struct sched_group { 2290 struct sched_group *next; /* Must be a circular list */ 2291 atomic_t ref; 2292 2293 unsigned int group_weight; 2294 unsigned int cores; 2295 struct sched_group_capacity *sgc; 2296 int asym_prefer_cpu; /* CPU of highest priority in group */ 2297 int flags; 2298 2299 /* 2300 * The CPUs this group covers. 2301 * 2302 * NOTE: this field is variable length. (Allocated dynamically 2303 * by attaching extra space to the end of the structure, 2304 * depending on how many CPUs the kernel has booted up with) 2305 */ 2306 unsigned long cpumask[]; 2307 }; 2308 2309 static inline struct cpumask *sched_group_span(struct sched_group *sg) 2310 { 2311 return to_cpumask(sg->cpumask); 2312 } 2313 2314 /* 2315 * See build_balance_mask(). 2316 */ 2317 static inline struct cpumask *group_balance_mask(struct sched_group *sg) 2318 { 2319 return to_cpumask(sg->sgc->cpumask); 2320 } 2321 2322 extern int group_balance_cpu(struct sched_group *sg); 2323 2324 extern void update_sched_domain_debugfs(void); 2325 extern void dirty_sched_domain_sysctl(int cpu); 2326 2327 extern int sched_update_scaling(void); 2328 2329 static inline const struct cpumask *task_user_cpus(struct task_struct *p) 2330 { 2331 if (!p->user_cpus_ptr) 2332 return cpu_possible_mask; /* &init_task.cpus_mask */ 2333 return p->user_cpus_ptr; 2334 } 2335 2336 #ifdef CONFIG_CGROUP_SCHED 2337 2338 /* 2339 * Return the group to which this tasks belongs. 2340 * 2341 * We cannot use task_css() and friends because the cgroup subsystem 2342 * changes that value before the cgroup_subsys::attach() method is called, 2343 * therefore we cannot pin it and might observe the wrong value. 2344 * 2345 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup 2346 * core changes this before calling sched_move_task(). 2347 * 2348 * Instead we use a 'copy' which is updated from sched_move_task() while 2349 * holding both task_struct::pi_lock and rq::lock. 2350 */ 2351 static inline struct task_group *task_group(struct task_struct *p) 2352 { 2353 return p->sched_task_group; 2354 } 2355 2356 #ifdef CONFIG_FAIR_GROUP_SCHED 2357 /* 2358 * Defined here to be available before stats.h is included, since 2359 * stats.h has dependencies on things defined later in this file. 2360 */ 2361 struct cfs_tg_state { 2362 struct cfs_rq cfs_rq; 2363 struct sched_entity se; 2364 struct sched_statistics stats; 2365 } __no_randomize_layout; 2366 2367 /* Access a specific CPU's cfs_rq from a task group */ 2368 static inline struct cfs_rq *tg_cfs_rq(struct task_group *tg, int cpu) 2369 { 2370 return per_cpu_ptr(tg->cfs_rq, cpu); 2371 } 2372 2373 static inline struct sched_entity *tg_se(struct task_group *tg, int cpu) 2374 { 2375 struct cfs_tg_state *state; 2376 2377 if (is_root_task_group(tg)) 2378 return NULL; 2379 2380 state = container_of(tg_cfs_rq(tg, cpu), struct cfs_tg_state, cfs_rq); 2381 return &state->se; 2382 } 2383 2384 static inline struct sched_entity *cfs_rq_se(struct cfs_rq *cfs_rq) 2385 { 2386 struct cfs_tg_state *state; 2387 2388 if (is_root_task_group(cfs_rq->tg)) 2389 return NULL; 2390 2391 state = container_of(cfs_rq, struct cfs_tg_state, cfs_rq); 2392 return &state->se; 2393 } 2394 #endif 2395 2396 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ 2397 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) 2398 { 2399 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED) 2400 struct task_group *tg = task_group(p); 2401 #endif 2402 2403 #ifdef CONFIG_FAIR_GROUP_SCHED 2404 set_task_rq_fair(&p->se, p->se.cfs_rq, tg_cfs_rq(tg, cpu)); 2405 p->se.cfs_rq = tg_cfs_rq(tg, cpu); 2406 p->se.parent = tg_se(tg, cpu); 2407 p->se.depth = p->se.parent ? p->se.parent->depth + 1 : 0; 2408 #endif 2409 2410 #ifdef CONFIG_RT_GROUP_SCHED 2411 /* 2412 * p->rt.rt_rq is NULL initially and it is easier to assign 2413 * root_task_group's rt_rq than switching in rt_rq_of_se() 2414 * Clobbers tg(!) 2415 */ 2416 if (!rt_group_sched_enabled()) 2417 tg = &root_task_group; 2418 p->rt.rt_rq = tg->rt_rq[cpu]; 2419 p->rt.parent = tg->rt_se[cpu]; 2420 #endif /* CONFIG_RT_GROUP_SCHED */ 2421 } 2422 2423 #else /* !CONFIG_CGROUP_SCHED: */ 2424 2425 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } 2426 2427 static inline struct task_group *task_group(struct task_struct *p) 2428 { 2429 return NULL; 2430 } 2431 2432 #endif /* !CONFIG_CGROUP_SCHED */ 2433 2434 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) 2435 { 2436 set_task_rq(p, cpu); 2437 #ifdef CONFIG_SMP 2438 /* 2439 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be 2440 * successfully executed on another CPU. We must ensure that updates of 2441 * per-task data have been completed by this moment. 2442 */ 2443 smp_wmb(); 2444 WRITE_ONCE(task_thread_info(p)->cpu, cpu); 2445 p->wake_cpu = cpu; 2446 rseq_sched_set_ids_changed(p); 2447 #endif /* CONFIG_SMP */ 2448 } 2449 2450 /* 2451 * Tunables: 2452 */ 2453 2454 #define SCHED_FEAT(name, enabled) \ 2455 __SCHED_FEAT_##name , 2456 2457 enum { 2458 #include "features.h" 2459 __SCHED_FEAT_NR, 2460 }; 2461 2462 #undef SCHED_FEAT 2463 2464 /* 2465 * To support run-time toggling of sched features, all the translation units 2466 * (but core.c) reference the sysctl_sched_features defined in core.c. 2467 */ 2468 extern __read_mostly unsigned int sysctl_sched_features; 2469 2470 #ifdef CONFIG_JUMP_LABEL 2471 2472 union sched_feat_key { 2473 struct static_key_true key_true; 2474 struct static_key_false key_false; 2475 }; 2476 2477 #define sched_feat_branch_true(key) static_branch_likely(&(key)->key_true) 2478 #define sched_feat_branch_false(key) static_branch_unlikely(&(key)->key_false) 2479 2480 #define SCHED_FEAT(name, enabled) \ 2481 static __always_inline bool \ 2482 static_branch_##name(union sched_feat_key *key) \ 2483 { \ 2484 return sched_feat_branch_##enabled(key); \ 2485 } 2486 2487 #include "features.h" 2488 #undef SCHED_FEAT 2489 2490 extern union sched_feat_key sched_feat_keys[__SCHED_FEAT_NR]; 2491 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x])) 2492 2493 #else /* !CONFIG_JUMP_LABEL: */ 2494 2495 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) 2496 2497 #endif /* !CONFIG_JUMP_LABEL */ 2498 2499 extern struct static_key_false sched_numa_balancing; 2500 extern struct static_key_false sched_schedstats; 2501 2502 static inline u64 global_rt_period(void) 2503 { 2504 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC; 2505 } 2506 2507 static inline u64 global_rt_runtime(void) 2508 { 2509 if (sysctl_sched_rt_runtime < 0) 2510 return RUNTIME_INF; 2511 2512 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC; 2513 } 2514 2515 /* 2516 * Is p the current execution context? 2517 */ 2518 static inline int task_current(struct rq *rq, struct task_struct *p) 2519 { 2520 return rq->curr == p; 2521 } 2522 2523 /* 2524 * Is p the current scheduling context? 2525 * 2526 * Note that it might be the current execution context at the same time if 2527 * rq->curr == rq->donor == p. 2528 */ 2529 static inline int task_current_donor(struct rq *rq, struct task_struct *p) 2530 { 2531 return rq->donor == p; 2532 } 2533 2534 static inline bool task_is_blocked(struct task_struct *p) 2535 { 2536 if (!sched_proxy_exec()) 2537 return false; 2538 2539 return !!p->blocked_on; 2540 } 2541 2542 #ifdef CONFIG_SCHED_PROXY_EXEC 2543 void sched_proxy_block_task(struct rq *rq, struct task_struct *p); 2544 #else 2545 static inline void sched_proxy_block_task(struct rq *rq, struct task_struct *p) {} 2546 #endif 2547 2548 static inline int task_on_cpu(struct rq *rq, struct task_struct *p) 2549 { 2550 return p->on_cpu; 2551 } 2552 2553 static inline int task_on_rq_queued(struct task_struct *p) 2554 { 2555 return READ_ONCE(p->on_rq) == TASK_ON_RQ_QUEUED; 2556 } 2557 2558 static inline int task_on_rq_migrating(struct task_struct *p) 2559 { 2560 return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING; 2561 } 2562 2563 /* Wake flags. The first three directly map to some SD flag value */ 2564 #define WF_EXEC 0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */ 2565 #define WF_FORK 0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */ 2566 #define WF_TTWU 0x08 /* Wakeup; maps to SD_BALANCE_WAKE */ 2567 /* 2568 * Hint that the caller expects the waker to sleep soon. 2569 * Scheduler classes may use it for placement or preemption. 2570 * Callers must not rely on it to prevent migration, 2571 * preserve CPU locality or make the wakee run next. 2572 */ 2573 #define WF_SYNC 0x10 2574 #define WF_MIGRATED 0x20 /* Internal use, task got migrated */ 2575 #define WF_CURRENT_CPU 0x40 /* Prefer to move the wakee to the current CPU. */ 2576 #define WF_RQ_SELECTED 0x80 /* ->select_task_rq() was called */ 2577 #define WF_TTWU_RQ 0x100 /* Wakeup completed through ttwu_runnable() */ 2578 2579 static_assert(WF_EXEC == SD_BALANCE_EXEC); 2580 static_assert(WF_FORK == SD_BALANCE_FORK); 2581 static_assert(WF_TTWU == SD_BALANCE_WAKE); 2582 2583 /* 2584 * To aid in avoiding the subversion of "niceness" due to uneven distribution 2585 * of tasks with abnormal "nice" values across CPUs the contribution that 2586 * each task makes to its run queue's load is weighted according to its 2587 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a 2588 * scaled version of the new time slice allocation that they receive on time 2589 * slice expiry etc. 2590 */ 2591 2592 #define WEIGHT_IDLEPRIO 3 2593 #define WMULT_IDLEPRIO 1431655765 2594 2595 extern const int sched_prio_to_weight[40]; 2596 extern const u32 sched_prio_to_wmult[40]; 2597 2598 /* 2599 * {de,en}queue flags: 2600 * 2601 * SLEEP/WAKEUP - task is no-longer/just-became runnable 2602 * 2603 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks 2604 * are in a known state which allows modification. Such pairs 2605 * should preserve as much state as possible. 2606 * 2607 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location 2608 * in the runqueue. IOW the priority is allowed to change. Callers 2609 * must expect to deal with balance callbacks. 2610 * 2611 * NOCLOCK - skip the update_rq_clock() (avoids double updates) 2612 * 2613 * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE) 2614 * 2615 * DELAYED - de/re-queue a sched_delayed task 2616 * 2617 * CLASS - going to update p->sched_class; makes sched_change call the 2618 * various switch methods. 2619 * 2620 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified) 2621 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline) 2622 * ENQUEUE_MIGRATED - the task was migrated during wakeup 2623 * ENQUEUE_RQ_SELECTED - ->select_task_rq() was called 2624 * 2625 * XXX SAVE/RESTORE in combination with CLASS doesn't really make sense, but 2626 * SCHED_DEADLINE seems to rely on this for now. 2627 */ 2628 2629 #define DEQUEUE_SLEEP 0x0001 /* Matches ENQUEUE_WAKEUP */ 2630 #define DEQUEUE_SAVE 0x0002 /* Matches ENQUEUE_RESTORE */ 2631 #define DEQUEUE_MOVE 0x0004 /* Matches ENQUEUE_MOVE */ 2632 #define DEQUEUE_NOCLOCK 0x0008 /* Matches ENQUEUE_NOCLOCK */ 2633 2634 #define DEQUEUE_MIGRATING 0x0010 /* Matches ENQUEUE_MIGRATING */ 2635 #define DEQUEUE_DELAYED 0x0020 /* Matches ENQUEUE_DELAYED */ 2636 #define DEQUEUE_CLASS 0x0040 /* Matches ENQUEUE_CLASS */ 2637 2638 #define DEQUEUE_SPECIAL 0x00010000 2639 #define DEQUEUE_THROTTLE 0x00020000 2640 2641 #define ENQUEUE_WAKEUP 0x0001 2642 #define ENQUEUE_RESTORE 0x0002 2643 #define ENQUEUE_MOVE 0x0004 2644 #define ENQUEUE_NOCLOCK 0x0008 2645 2646 #define ENQUEUE_MIGRATING 0x0010 2647 #define ENQUEUE_DELAYED 0x0020 2648 #define ENQUEUE_CLASS 0x0040 2649 2650 #define ENQUEUE_HEAD 0x00010000 2651 #define ENQUEUE_REPLENISH 0x00020000 2652 #define ENQUEUE_MIGRATED 0x00040000 2653 #define ENQUEUE_INITIAL 0x00080000 2654 #define ENQUEUE_RQ_SELECTED 0x00100000 2655 #define ENQUEUE_QUEUED 0x00200000 2656 2657 #define RETRY_TASK ((void *)-1UL) 2658 2659 struct affinity_context { 2660 const struct cpumask *new_mask; 2661 struct cpumask *user_mask; 2662 unsigned int flags; 2663 }; 2664 2665 extern s64 update_curr_common(struct rq *rq); 2666 2667 enum snt_e { 2668 SNT_NORMAL, /* set_next_task() */ 2669 SNT_PICK, /* put_prev_set_next_task(): prev != next */ 2670 SNT_REPICK, /* put_prev_set_next_task(): prev == next */ 2671 }; 2672 2673 struct sched_class { 2674 2675 #ifdef CONFIG_UCLAMP_TASK 2676 int uclamp_enabled; 2677 #endif 2678 2679 /* 2680 * move_queued_task/activate_task/enqueue_task: rq->lock 2681 * ttwu_do_activate/activate_task/enqueue_task: rq->lock 2682 * wake_up_new_task/activate_task/enqueue_task: task_rq_lock 2683 * ttwu_runnable/enqueue_task: task_rq_lock 2684 * proxy_task_current: rq->lock 2685 * sched_change_end 2686 */ 2687 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags); 2688 /* 2689 * move_queued_task/deactivate_task/dequeue_task: rq->lock 2690 * __schedule/block_task/dequeue_task: rq->lock 2691 * proxy_task_current: rq->lock 2692 * wait_task_inactive: task_rq_lock 2693 * sched_change_begin 2694 */ 2695 bool (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags); 2696 2697 /* 2698 * do_sched_yield: rq->lock 2699 */ 2700 void (*yield_task) (struct rq *rq); 2701 /* 2702 * yield_to: rq->lock (double) 2703 */ 2704 bool (*yield_to_task)(struct rq *rq, struct task_struct *p); 2705 2706 /* 2707 * move_queued_task: rq->lock 2708 * __migrate_swap_task: rq->lock 2709 * ttwu_do_activate: rq->lock 2710 * ttwu_runnable: task_rq_lock 2711 * wake_up_new_task: task_rq_lock 2712 */ 2713 void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags); 2714 2715 /* 2716 * schedule/pick_next_task/prev_balance: rq->lock 2717 */ 2718 int (*balance)(struct rq *rq, struct rq_flags *rf); 2719 2720 /* 2721 * schedule/pick_next_task: rq->lock 2722 */ 2723 struct task_struct *(*pick_task)(struct rq *rq, struct rq_flags *rf); 2724 2725 /* 2726 * sched_change: 2727 * __schedule: rq->lock 2728 */ 2729 void (*put_prev_task)(struct rq *rq, struct task_struct *p, struct task_struct *next); 2730 void (*set_next_task)(struct rq *rq, struct task_struct *p, enum snt_e type); 2731 2732 /* 2733 * select_task_rq: p->pi_lock 2734 * sched_exec: p->pi_lock 2735 */ 2736 int (*select_task_rq)(struct task_struct *p, int task_cpu, int flags); 2737 2738 /* 2739 * set_task_cpu: p->pi_lock || rq->lock (ttwu like) 2740 */ 2741 void (*migrate_task_rq)(struct task_struct *p, int new_cpu); 2742 2743 /* 2744 * ttwu_do_activate: rq->lock 2745 * wake_up_new_task: task_rq_lock 2746 */ 2747 void (*task_woken)(struct rq *this_rq, struct task_struct *task); 2748 2749 /* 2750 * do_set_cpus_allowed: task_rq_lock + sched_change 2751 */ 2752 void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx); 2753 2754 /* 2755 * sched_set_rq_{on,off}line: rq->lock 2756 */ 2757 void (*rq_online)(struct rq *rq); 2758 void (*rq_offline)(struct rq *rq); 2759 2760 /* 2761 * push_cpu_stop: p->pi_lock && rq->lock 2762 */ 2763 struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq); 2764 2765 /* 2766 * hrtick: rq->lock 2767 * sched_tick: rq->lock 2768 * sched_tick_remote: rq->lock 2769 */ 2770 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued); 2771 /* 2772 * sched_cgroup_fork: p->pi_lock 2773 */ 2774 void (*task_fork)(struct task_struct *p); 2775 /* 2776 * finish_task_switch: no locks 2777 */ 2778 void (*task_dead)(struct task_struct *p); 2779 2780 /* 2781 * sched_change 2782 */ 2783 void (*switching_from)(struct rq *this_rq, struct task_struct *task); 2784 void (*switched_from) (struct rq *this_rq, struct task_struct *task); 2785 void (*switching_to) (struct rq *this_rq, struct task_struct *task); 2786 void (*switched_to) (struct rq *this_rq, struct task_struct *task); 2787 u64 (*get_prio) (struct rq *this_rq, struct task_struct *task); 2788 void (*prio_changed) (struct rq *this_rq, struct task_struct *task, 2789 u64 oldprio); 2790 2791 /* 2792 * set_load_weight: task_rq_lock + sched_change 2793 * __setscheduler_parms: task_rq_lock + sched_change 2794 */ 2795 void (*reweight_task)(struct rq *this_rq, struct task_struct *task, 2796 const struct load_weight *lw); 2797 2798 /* 2799 * sched_rr_get_interval: task_rq_lock 2800 */ 2801 unsigned int (*get_rr_interval)(struct rq *rq, 2802 struct task_struct *task); 2803 2804 /* 2805 * task_sched_runtime: task_rq_lock 2806 */ 2807 void (*update_curr)(struct rq *rq); 2808 2809 #ifdef CONFIG_FAIR_GROUP_SCHED 2810 /* 2811 * sched_change_group: task_rq_lock + sched_change 2812 */ 2813 void (*task_change_group)(struct task_struct *p); 2814 #endif 2815 2816 #ifdef CONFIG_SCHED_CORE 2817 /* 2818 * pick_next_task: rq->lock 2819 * try_steal_cookie: rq->lock (double) 2820 */ 2821 int (*task_is_throttled)(struct task_struct *p, int cpu); 2822 #endif 2823 }; 2824 2825 static inline void put_prev_task(struct rq *rq, struct task_struct *prev) 2826 { 2827 WARN_ON_ONCE(rq->donor != prev); 2828 prev->sched_class->put_prev_task(rq, prev, NULL); 2829 } 2830 2831 static inline void set_next_task(struct rq *rq, struct task_struct *next) 2832 { 2833 next->sched_class->set_next_task(rq, next, SNT_NORMAL); 2834 } 2835 2836 static inline void 2837 __put_prev_set_next_dl_server(struct rq *rq, 2838 struct task_struct *prev, 2839 struct task_struct *next) 2840 { 2841 prev->dl_server = NULL; 2842 next->dl_server = rq->dl_server; 2843 rq->dl_server = NULL; 2844 } 2845 2846 static inline void put_prev_set_next_task(struct rq *rq, 2847 struct task_struct *prev, 2848 struct task_struct *next) 2849 { 2850 WARN_ON_ONCE(rq->donor != prev); 2851 2852 __put_prev_set_next_dl_server(rq, prev, next); 2853 2854 if (next == prev) { 2855 next->sched_class->set_next_task(rq, next, SNT_REPICK); 2856 return; 2857 } 2858 2859 prev->sched_class->put_prev_task(rq, prev, next); 2860 next->sched_class->set_next_task(rq, next, SNT_PICK); 2861 } 2862 2863 /* 2864 * Helper to define a sched_class instance; each one is placed in a separate 2865 * section which is ordered by the linker script: 2866 * 2867 * include/asm-generic/vmlinux.lds.h 2868 * 2869 * *CAREFUL* they are laid out in *REVERSE* order!!! 2870 * 2871 * Also enforce alignment on the instance, not the type, to guarantee layout. 2872 */ 2873 #define DEFINE_SCHED_CLASS(name) \ 2874 const struct sched_class name##_sched_class \ 2875 __aligned(__alignof__(struct sched_class)) \ 2876 __section("__" #name "_sched_class") 2877 2878 /* Defined in include/asm-generic/vmlinux.lds.h */ 2879 extern struct sched_class __sched_class_highest[]; 2880 extern struct sched_class __sched_class_lowest[]; 2881 2882 extern const struct sched_class stop_sched_class; 2883 extern const struct sched_class dl_sched_class; 2884 extern const struct sched_class rt_sched_class; 2885 extern const struct sched_class fair_sched_class; 2886 extern const struct sched_class idle_sched_class; 2887 2888 /* 2889 * Iterate only active classes. SCX can take over all fair tasks or be 2890 * completely disabled. If the former, skip fair. If the latter, skip SCX. 2891 */ 2892 static inline const struct sched_class *next_active_class(const struct sched_class *class) 2893 { 2894 class++; 2895 #ifdef CONFIG_SCHED_CLASS_EXT 2896 if (scx_switched_all() && class == &fair_sched_class) 2897 class++; 2898 if (!scx_enabled() && class == &ext_sched_class) 2899 class++; 2900 #endif 2901 return class; 2902 } 2903 2904 #define for_class_range(class, _from, _to) \ 2905 for (class = (_from); class < (_to); class++) 2906 2907 #define for_each_class(class) \ 2908 for_class_range(class, __sched_class_highest, __sched_class_lowest) 2909 2910 #define for_active_class_range(class, _from, _to) \ 2911 for (class = (_from); class != (_to); class = next_active_class(class)) 2912 2913 #define for_each_active_class(class) \ 2914 for_active_class_range(class, __sched_class_highest, __sched_class_lowest) 2915 2916 #define sched_class_above(_a, _b) ((_a) < (_b)) 2917 2918 static inline void rq_modified_begin(struct rq *rq, const struct sched_class *class) 2919 { 2920 if (sched_class_above(rq->next_class, class)) 2921 rq->next_class = class; 2922 } 2923 2924 static inline bool rq_modified_above(struct rq *rq, const struct sched_class *class) 2925 { 2926 return sched_class_above(rq->next_class, class); 2927 } 2928 2929 static inline bool sched_stop_runnable(struct rq *rq) 2930 { 2931 return rq->stop && task_on_rq_queued(rq->stop); 2932 } 2933 2934 static inline bool sched_dl_runnable(struct rq *rq) 2935 { 2936 return rq->dl.dl_nr_running > 0; 2937 } 2938 2939 static inline bool sched_rt_runnable(struct rq *rq) 2940 { 2941 return rq->rt.rt_queued > 0; 2942 } 2943 2944 static inline bool sched_fair_runnable(struct rq *rq) 2945 { 2946 return rq->cfs.nr_queued > 0; 2947 } 2948 2949 extern struct task_struct *pick_task_fair(struct rq *rq, struct rq_flags *rf); 2950 extern struct task_struct *pick_task_idle(struct rq *rq, struct rq_flags *rf); 2951 2952 #define SCA_CHECK 0x01 2953 #define SCA_MIGRATE_DISABLE 0x02 2954 #define SCA_MIGRATE_ENABLE 0x04 2955 #define SCA_USER 0x08 2956 2957 extern void update_group_capacity(struct sched_domain *sd, int cpu); 2958 2959 extern void sched_balance_trigger(struct rq *rq); 2960 2961 extern int __set_cpus_allowed_ptr(struct task_struct *p, struct affinity_context *ctx); 2962 extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx); 2963 2964 static inline bool task_allowed_on_cpu(struct task_struct *p, int cpu) 2965 { 2966 /* When not in the task's cpumask, no point in looking further. */ 2967 if (!cpumask_test_cpu(cpu, p->cpus_ptr)) 2968 return false; 2969 2970 /* Can @cpu run a user thread? */ 2971 if (!(p->flags & PF_KTHREAD) && !task_cpu_possible(cpu, p)) 2972 return false; 2973 2974 return true; 2975 } 2976 2977 static inline cpumask_t *alloc_user_cpus_ptr(int node) 2978 { 2979 /* 2980 * See set_cpus_allowed_force() above for the rcu_head usage. 2981 */ 2982 int size = max_t(int, cpumask_size(), sizeof(struct rcu_head)); 2983 2984 return kmalloc_node(size, GFP_KERNEL, node); 2985 } 2986 2987 static inline struct task_struct *get_push_task(struct rq *rq) 2988 { 2989 struct task_struct *p = rq->donor; 2990 2991 lockdep_assert_rq_held(rq); 2992 2993 if (rq->push_busy) 2994 return NULL; 2995 2996 if (p->nr_cpus_allowed == 1) 2997 return NULL; 2998 2999 if (p->migration_disabled) 3000 return NULL; 3001 3002 rq->push_busy = true; 3003 return get_task_struct(p); 3004 } 3005 3006 extern int push_cpu_stop(void *arg); 3007 3008 #ifdef CONFIG_CPU_IDLE 3009 3010 static inline void idle_set_state(struct rq *rq, 3011 struct cpuidle_state *idle_state) 3012 { 3013 rq->idle_state = idle_state; 3014 } 3015 3016 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 3017 { 3018 lockdep_assert(rcu_read_lock_any_held()); 3019 3020 return rq->idle_state; 3021 } 3022 3023 #else /* !CONFIG_CPU_IDLE: */ 3024 3025 static inline void idle_set_state(struct rq *rq, 3026 struct cpuidle_state *idle_state) 3027 { 3028 } 3029 3030 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 3031 { 3032 return NULL; 3033 } 3034 3035 #endif /* !CONFIG_CPU_IDLE */ 3036 3037 extern void schedule_idle(void); 3038 asmlinkage void schedule_user(void); 3039 3040 extern void sysrq_sched_debug_show(void); 3041 extern void sched_init_granularity(void); 3042 extern void update_max_interval(void); 3043 3044 extern void init_sched_dl_class(void); 3045 extern void init_sched_rt_class(void); 3046 extern void init_sched_fair_class(void); 3047 3048 extern void resched_curr(struct rq *rq); 3049 extern void resched_curr_lazy(struct rq *rq); 3050 extern void resched_cpu(int cpu); 3051 3052 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime); 3053 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq); 3054 3055 extern void init_dl_entity(struct sched_dl_entity *dl_se); 3056 3057 extern void init_cfs_throttle_work(struct task_struct *p); 3058 3059 #define BW_SHIFT 20 3060 #define BW_UNIT (1 << BW_SHIFT) 3061 #define RATIO_SHIFT 8 3062 #define MAX_BW_BITS (64 - BW_SHIFT) 3063 #define MAX_BW ((1ULL << MAX_BW_BITS) - 1) 3064 3065 extern u64 to_ratio(u64 period, u64 runtime); 3066 3067 extern void init_entity_runnable_average(struct sched_entity *se); 3068 extern void post_init_entity_util_avg(struct task_struct *p); 3069 3070 #ifdef CONFIG_NO_HZ_FULL 3071 extern bool sched_can_stop_tick(struct rq *rq); 3072 extern int __init sched_tick_offload_init(void); 3073 3074 /* 3075 * Tick may be needed by tasks in the runqueue depending on their policy and 3076 * requirements. If tick is needed, lets send the target an IPI to kick it out of 3077 * nohz mode if necessary. 3078 */ 3079 static inline void sched_update_tick_dependency(struct rq *rq) 3080 { 3081 int cpu = cpu_of(rq); 3082 3083 if (!tick_nohz_full_cpu(cpu)) 3084 return; 3085 3086 if (sched_can_stop_tick(rq)) 3087 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED); 3088 else 3089 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED); 3090 } 3091 #else /* !CONFIG_NO_HZ_FULL: */ 3092 static inline int sched_tick_offload_init(void) { return 0; } 3093 static inline void sched_update_tick_dependency(struct rq *rq) { } 3094 #endif /* !CONFIG_NO_HZ_FULL */ 3095 3096 static inline void add_nr_running(struct rq *rq, unsigned count) 3097 { 3098 unsigned prev_nr = rq->nr_running; 3099 3100 rq->nr_running = prev_nr + count; 3101 if (trace_sched_update_nr_running_tp_enabled()) { 3102 call_trace_sched_update_nr_running(rq, count); 3103 } 3104 3105 if (prev_nr < 2 && rq->nr_running >= 2) 3106 set_rd_overloaded(rq->rd, 1); 3107 3108 sched_update_tick_dependency(rq); 3109 } 3110 3111 static inline void sub_nr_running(struct rq *rq, unsigned count) 3112 { 3113 rq->nr_running -= count; 3114 if (trace_sched_update_nr_running_tp_enabled()) { 3115 call_trace_sched_update_nr_running(rq, -count); 3116 } 3117 3118 /* Check if we still need preemption */ 3119 sched_update_tick_dependency(rq); 3120 } 3121 3122 static inline void __block_task(struct rq *rq, struct task_struct *p) 3123 { 3124 if (p->sched_contributes_to_load) 3125 rq->nr_uninterruptible++; 3126 3127 ASSERT_EXCLUSIVE_WRITER(p->on_rq); 3128 3129 /* 3130 * The moment this write goes through, ttwu() can swoop in and migrate 3131 * this task, rendering our rq->__lock ineffective. 3132 * 3133 * __schedule() try_to_wake_up() 3134 * LOCK rq->__lock LOCK p->pi_lock 3135 * pick_next_task() 3136 * pick_next_task_fair() 3137 * pick_next_entity() 3138 * dequeue_entities() 3139 * __block_task() 3140 * RELEASE p->on_rq = 0 if (p->on_rq && ...) 3141 * break; 3142 * 3143 * ACQUIRE (after ctrl-dep) 3144 * 3145 * cpu = select_task_rq(); 3146 * set_task_cpu(p, cpu); 3147 * ttwu_queue() 3148 * ttwu_do_activate() 3149 * LOCK rq->__lock 3150 * activate_task() 3151 * STORE p->on_rq = 1 3152 * UNLOCK rq->__lock 3153 * 3154 * Callers must ensure to not reference @p after this -- we no longer 3155 * own it. 3156 */ 3157 smp_store_release(&p->on_rq, 0); 3158 } 3159 3160 extern void activate_task(struct rq *rq, struct task_struct *p, int flags); 3161 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags); 3162 3163 extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags); 3164 3165 /* 3166 * attach_task() -- attach the task detached by detach_task() to its new rq. 3167 */ 3168 static inline void attach_task(struct rq *rq, struct task_struct *p) 3169 { 3170 lockdep_assert_rq_held(rq); 3171 3172 WARN_ON_ONCE(task_rq(p) != rq); 3173 activate_task(rq, p, ENQUEUE_NOCLOCK); 3174 wakeup_preempt(rq, p, 0); 3175 } 3176 3177 /* 3178 * attach_one_task() -- attaches the task returned from detach_one_task() to 3179 * its new rq. 3180 */ 3181 static inline void attach_one_task(struct rq *rq, struct task_struct *p) 3182 { 3183 guard(rq_lock)(rq); 3184 update_rq_clock(rq); 3185 attach_task(rq, p); 3186 } 3187 3188 /* 3189 * __attach_tasks() - attaches a list of tasks (using se.group_node) to 3190 * the new rq 3191 */ 3192 static inline void __attach_tasks(struct rq *rq, struct list_head *tasks) 3193 { 3194 guard(rq_lock)(rq); 3195 update_rq_clock(rq); 3196 3197 while (!list_empty(tasks)) { 3198 struct task_struct *p; 3199 3200 p = list_first_entry(tasks, struct task_struct, se.group_node); 3201 list_del_init(&p->se.group_node); 3202 3203 attach_task(rq, p); 3204 } 3205 } 3206 3207 #ifdef CONFIG_PREEMPT_RT 3208 # define SCHED_NR_MIGRATE_BREAK 8 3209 #else 3210 # define SCHED_NR_MIGRATE_BREAK 32 3211 #endif 3212 3213 extern __read_mostly unsigned int sysctl_sched_nr_migrate; 3214 extern __read_mostly unsigned int sysctl_sched_migration_cost; 3215 3216 extern unsigned int sysctl_sched_base_slice; 3217 3218 extern int sysctl_resched_latency_warn_ms; 3219 extern int sysctl_resched_latency_warn_once; 3220 3221 extern unsigned int sysctl_sched_tunable_scaling; 3222 3223 extern unsigned int sysctl_numa_balancing_scan_delay; 3224 extern unsigned int sysctl_numa_balancing_scan_period_min; 3225 extern unsigned int sysctl_numa_balancing_scan_period_max; 3226 extern unsigned int sysctl_numa_balancing_scan_size; 3227 extern unsigned int sysctl_numa_balancing_hot_threshold; 3228 3229 #ifdef CONFIG_SCHED_HRTICK 3230 3231 /* 3232 * Use hrtick when: 3233 * - enabled by features 3234 * - hrtimer is actually high res 3235 */ 3236 static inline bool hrtick_enabled(struct rq *rq) 3237 { 3238 return cpu_active(cpu_of(rq)) && hrtimer_highres_enabled(); 3239 } 3240 3241 static inline bool hrtick_enabled_fair(struct rq *rq) 3242 { 3243 return sched_feat(HRTICK) && hrtick_enabled(rq); 3244 } 3245 3246 static inline bool hrtick_enabled_dl(struct rq *rq) 3247 { 3248 return sched_feat(HRTICK_DL) && hrtick_enabled(rq); 3249 } 3250 3251 extern void hrtick_start(struct rq *rq, u64 delay); 3252 static inline bool hrtick_active(struct rq *rq) 3253 { 3254 return hrtimer_active(&rq->hrtick_timer); 3255 } 3256 3257 #else /* !CONFIG_SCHED_HRTICK: */ 3258 static inline bool hrtick_enabled_fair(struct rq *rq) { return false; } 3259 static inline bool hrtick_enabled_dl(struct rq *rq) { return false; } 3260 static inline bool hrtick_enabled(struct rq *rq) { return false; } 3261 #endif /* !CONFIG_SCHED_HRTICK */ 3262 3263 #ifndef arch_scale_freq_tick 3264 static __always_inline void arch_scale_freq_tick(void) { } 3265 #endif 3266 3267 #ifndef arch_scale_freq_capacity 3268 /** 3269 * arch_scale_freq_capacity - get the frequency scale factor of a given CPU. 3270 * @cpu: the CPU in question. 3271 * 3272 * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e. 3273 * 3274 * f_curr 3275 * ------ * SCHED_CAPACITY_SCALE 3276 * f_max 3277 */ 3278 static __always_inline 3279 unsigned long arch_scale_freq_capacity(int cpu) 3280 { 3281 return SCHED_CAPACITY_SCALE; 3282 } 3283 #endif 3284 3285 /* 3286 * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to 3287 * acquire rq lock instead of rq_lock(). So at the end of these two functions 3288 * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of 3289 * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning. 3290 */ 3291 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) 3292 { 3293 rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 3294 rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 3295 } 3296 3297 #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...) \ 3298 __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__) \ 3299 static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2) \ 3300 __no_context_analysis \ 3301 { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t; \ 3302 _lock; return _t; } 3303 #define DECLARE_LOCK_GUARD_2_ATTRS(_name, _lock, _unlock1, _unlock2) \ 3304 static inline class_##_name##_t class_##_name##_constructor(lock_##_name##_t *_T1, \ 3305 lock_##_name##_t *_T2) _lock; \ 3306 static __always_inline void __class_##_name##_cleanup_ctx1(class_##_name##_t **_T1) \ 3307 __no_context_analysis _unlock1 { } \ 3308 static __always_inline void __class_##_name##_cleanup_ctx2(class_##_name##_t **_T2) \ 3309 __no_context_analysis _unlock2 { } 3310 #define WITH_LOCK_GUARD_2_ATTRS(_name, _T1, _T2) \ 3311 class_##_name##_constructor(_T1, _T2), \ 3312 *__UNIQUE_ID(unlock1) __cleanup(__class_##_name##_cleanup_ctx1) = (void *)(_T1),\ 3313 *__UNIQUE_ID(unlock2) __cleanup(__class_##_name##_cleanup_ctx2) = (void *)(_T2) 3314 3315 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2) 3316 { 3317 #ifdef CONFIG_SCHED_CORE 3318 /* 3319 * In order to not have {0,2},{1,3} turn into into an AB-BA, 3320 * order by core-id first and cpu-id second. 3321 * 3322 * Notably: 3323 * 3324 * double_rq_lock(0,3); will take core-0, core-1 lock 3325 * double_rq_lock(1,2); will take core-1, core-0 lock 3326 * 3327 * when only cpu-id is considered. 3328 */ 3329 if (rq1->core->cpu < rq2->core->cpu) 3330 return true; 3331 if (rq1->core->cpu > rq2->core->cpu) 3332 return false; 3333 3334 /* 3335 * __sched_core_flip() relies on SMT having cpu-id lock order. 3336 */ 3337 #endif /* CONFIG_SCHED_CORE */ 3338 return rq1->cpu < rq2->cpu; 3339 } 3340 3341 extern void double_rq_lock(struct rq *rq1, struct rq *rq2) 3342 __acquires(__rq_lockp(rq1), __rq_lockp(rq2)); 3343 3344 #ifdef CONFIG_PREEMPTION 3345 3346 /* 3347 * fair double_lock_balance: Safely acquires both rq->locks in a fair 3348 * way at the expense of forcing extra atomic operations in all 3349 * invocations. This assures that the double_lock is acquired using the 3350 * same underlying policy as the spinlock_t on this architecture, which 3351 * reduces latency compared to the unfair variant below. However, it 3352 * also adds more overhead and therefore may reduce throughput. 3353 */ 3354 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 3355 __must_hold(__rq_lockp(this_rq)) 3356 __acquires(__rq_lockp(busiest)) 3357 { 3358 raw_spin_rq_unlock(this_rq); 3359 double_rq_lock(this_rq, busiest); 3360 3361 return 1; 3362 } 3363 3364 #else /* !CONFIG_PREEMPTION: */ 3365 /* 3366 * Unfair double_lock_balance: Optimizes throughput at the expense of 3367 * latency by eliminating extra atomic operations when the locks are 3368 * already in proper order on entry. This favors lower CPU-ids and will 3369 * grant the double lock to lower CPUs over higher ids under contention, 3370 * regardless of entry order into the function. 3371 */ 3372 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 3373 __must_hold(__rq_lockp(this_rq)) 3374 __acquires(__rq_lockp(busiest)) 3375 { 3376 if (__rq_lockp(this_rq) == __rq_lockp(busiest)) { 3377 __acquire(__rq_lockp(busiest)); /* already held */ 3378 double_rq_clock_clear_update(this_rq, busiest); 3379 return 0; 3380 } 3381 3382 if (likely(raw_spin_rq_trylock(busiest))) { 3383 double_rq_clock_clear_update(this_rq, busiest); 3384 return 0; 3385 } 3386 3387 if (rq_order_less(this_rq, busiest)) { 3388 raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING); 3389 double_rq_clock_clear_update(this_rq, busiest); 3390 return 0; 3391 } 3392 3393 raw_spin_rq_unlock(this_rq); 3394 double_rq_lock(this_rq, busiest); 3395 3396 return 1; 3397 } 3398 3399 #endif /* !CONFIG_PREEMPTION */ 3400 3401 /* 3402 * double_lock_balance - lock the busiest runqueue, this_rq is locked already. 3403 */ 3404 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest) 3405 __must_hold(__rq_lockp(this_rq)) 3406 __acquires(__rq_lockp(busiest)) 3407 { 3408 lockdep_assert_irqs_disabled(); 3409 3410 return _double_lock_balance(this_rq, busiest); 3411 } 3412 3413 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest) 3414 __releases(__rq_lockp(busiest)) 3415 { 3416 if (__rq_lockp(this_rq) != __rq_lockp(busiest)) 3417 raw_spin_rq_unlock(busiest); 3418 else 3419 __release(__rq_lockp(busiest)); /* fake release */ 3420 lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_); 3421 } 3422 3423 static inline void double_lock(spinlock_t *l1, spinlock_t *l2) 3424 __acquires(l1, l2) 3425 { 3426 if (l1 > l2) 3427 swap(l1, l2); 3428 3429 spin_lock(l1); 3430 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 3431 } 3432 3433 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2) 3434 __acquires(l1, l2) 3435 { 3436 if (l1 > l2) 3437 swap(l1, l2); 3438 3439 spin_lock_irq(l1); 3440 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 3441 } 3442 3443 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2) 3444 __acquires(l1, l2) 3445 { 3446 if (l1 > l2) 3447 swap(l1, l2); 3448 3449 raw_spin_lock(l1); 3450 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 3451 } 3452 3453 static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2) 3454 __releases(l1, l2) 3455 { 3456 raw_spin_unlock(l1); 3457 raw_spin_unlock(l2); 3458 } 3459 3460 DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t, 3461 double_raw_lock(_T->lock, _T->lock2), 3462 double_raw_unlock(_T->lock, _T->lock2)) 3463 3464 DECLARE_LOCK_GUARD_2_ATTRS(double_raw_spinlock, 3465 __acquires(_T1, _T2), 3466 __releases(*(raw_spinlock_t **)_T1), 3467 __releases(*(raw_spinlock_t **)_T2)); 3468 #define class_double_raw_spinlock_constructor(_T1, _T2) \ 3469 WITH_LOCK_GUARD_2_ATTRS(double_raw_spinlock, _T1, _T2) 3470 3471 /* 3472 * double_rq_unlock - safely unlock two runqueues 3473 * 3474 * Note this does not restore interrupts like task_rq_unlock, 3475 * you need to do so manually after calling. 3476 */ 3477 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 3478 __releases(__rq_lockp(rq1), __rq_lockp(rq2)) 3479 { 3480 if (__rq_lockp(rq1) != __rq_lockp(rq2)) 3481 raw_spin_rq_unlock(rq2); 3482 else 3483 __release(__rq_lockp(rq2)); /* fake release */ 3484 raw_spin_rq_unlock(rq1); 3485 } 3486 3487 extern void set_rq_online (struct rq *rq); 3488 extern void set_rq_offline(struct rq *rq); 3489 3490 extern bool sched_smp_initialized; 3491 3492 DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq, 3493 double_rq_lock(_T->lock, _T->lock2), 3494 double_rq_unlock(_T->lock, _T->lock2)) 3495 3496 extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq); 3497 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq); 3498 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq); 3499 3500 extern bool sched_debug_verbose; 3501 3502 extern void print_cfs_stats(struct seq_file *m, int cpu); 3503 extern void print_rt_stats(struct seq_file *m, int cpu); 3504 extern void print_dl_stats(struct seq_file *m, int cpu); 3505 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 3506 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq); 3507 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq); 3508 3509 extern void resched_latency_warn(int cpu, u64 latency); 3510 3511 #ifdef CONFIG_NUMA_BALANCING 3512 extern void show_numa_stats(struct task_struct *p, struct seq_file *m); 3513 extern void 3514 print_numa_stats(struct seq_file *m, int node, unsigned long tsf, 3515 unsigned long tpf, unsigned long gsf, unsigned long gpf); 3516 #endif /* CONFIG_NUMA_BALANCING */ 3517 3518 extern void init_cfs_rq(struct cfs_rq *cfs_rq); 3519 extern void init_rt_rq(struct rt_rq *rt_rq); 3520 extern void init_dl_rq(struct dl_rq *dl_rq); 3521 3522 extern void cfs_bandwidth_usage_inc(void); 3523 extern void cfs_bandwidth_usage_dec(void); 3524 3525 #ifdef CONFIG_NO_HZ_COMMON 3526 3527 #define NOHZ_BALANCE_KICK_BIT 0 3528 #define NOHZ_STATS_KICK_BIT 1 3529 #define NOHZ_NEWILB_KICK_BIT 2 3530 #define NOHZ_NEXT_KICK_BIT 3 3531 3532 /* Run sched_balance_domains() */ 3533 #define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT) 3534 /* Update blocked load */ 3535 #define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT) 3536 /* Update blocked load when entering idle */ 3537 #define NOHZ_NEWILB_KICK BIT(NOHZ_NEWILB_KICK_BIT) 3538 /* Update nohz.next_balance */ 3539 #define NOHZ_NEXT_KICK BIT(NOHZ_NEXT_KICK_BIT) 3540 3541 #define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK) 3542 3543 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags) 3544 3545 extern void nohz_balance_exit_idle(struct rq *rq); 3546 #else /* !CONFIG_NO_HZ_COMMON: */ 3547 static inline void nohz_balance_exit_idle(struct rq *rq) { } 3548 #endif /* !CONFIG_NO_HZ_COMMON */ 3549 3550 #ifdef CONFIG_NO_HZ_COMMON 3551 extern void nohz_run_idle_balance(int cpu); 3552 #else 3553 static inline void nohz_run_idle_balance(int cpu) { } 3554 #endif 3555 3556 #include "stats.h" 3557 3558 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS) 3559 3560 extern void __sched_core_account_forceidle(struct rq *rq); 3561 3562 static inline void sched_core_account_forceidle(struct rq *rq) 3563 { 3564 if (schedstat_enabled()) 3565 __sched_core_account_forceidle(rq); 3566 } 3567 3568 extern void __sched_core_tick(struct rq *rq); 3569 3570 static inline void sched_core_tick(struct rq *rq) 3571 { 3572 if (sched_core_enabled(rq) && schedstat_enabled()) 3573 __sched_core_tick(rq); 3574 } 3575 3576 #else /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS): */ 3577 3578 static inline void sched_core_account_forceidle(struct rq *rq) { } 3579 3580 static inline void sched_core_tick(struct rq *rq) { } 3581 3582 #endif /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS) */ 3583 3584 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 3585 3586 struct irqtime { 3587 u64 total; 3588 u64 tick_delta; 3589 u64 irq_start_time; 3590 struct u64_stats_sync sync; 3591 }; 3592 3593 DECLARE_PER_CPU(struct irqtime, cpu_irqtime); 3594 DECLARE_STATIC_KEY_FALSE(sched_clock_irqtime); 3595 3596 static inline int irqtime_enabled(void) 3597 { 3598 return static_branch_likely(&sched_clock_irqtime); 3599 } 3600 3601 /* 3602 * Returns the irqtime minus the softirq time computed by ksoftirqd. 3603 * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime 3604 * and never move forward. 3605 */ 3606 static inline u64 irq_time_read(int cpu) 3607 { 3608 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu); 3609 unsigned int seq; 3610 u64 total; 3611 3612 do { 3613 seq = __u64_stats_fetch_begin(&irqtime->sync); 3614 total = irqtime->total; 3615 } while (__u64_stats_fetch_retry(&irqtime->sync, seq)); 3616 3617 return total; 3618 } 3619 3620 #else /* !CONFIG_IRQ_TIME_ACCOUNTING: */ 3621 3622 static inline int irqtime_enabled(void) 3623 { 3624 return 0; 3625 } 3626 3627 #endif /* !CONFIG_IRQ_TIME_ACCOUNTING */ 3628 3629 #ifdef CONFIG_CPU_FREQ 3630 3631 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data); 3632 3633 /** 3634 * cpufreq_update_util - Take a note about CPU utilization changes. 3635 * @rq: Runqueue to carry out the update for. 3636 * @flags: Update reason flags. 3637 * 3638 * This function is called by the scheduler on the CPU whose utilization is 3639 * being updated. 3640 * 3641 * It can only be called from RCU-sched read-side critical sections. 3642 * 3643 * The way cpufreq is currently arranged requires it to evaluate the CPU 3644 * performance state (frequency/voltage) on a regular basis to prevent it from 3645 * being stuck in a completely inadequate performance level for too long. 3646 * That is not guaranteed to happen if the updates are only triggered from CFS 3647 * and DL, though, because they may not be coming in if only RT tasks are 3648 * active all the time (or there are RT tasks only). 3649 * 3650 * As a workaround for that issue, this function is called periodically by the 3651 * RT sched class to trigger extra cpufreq updates to prevent it from stalling, 3652 * but that really is a band-aid. Going forward it should be replaced with 3653 * solutions targeted more specifically at RT tasks. 3654 */ 3655 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) 3656 { 3657 struct update_util_data *data; 3658 3659 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data, 3660 cpu_of(rq))); 3661 if (data) 3662 data->func(data, rq_clock(rq), flags); 3663 } 3664 #else /* !CONFIG_CPU_FREQ: */ 3665 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) { } 3666 #endif /* !CONFIG_CPU_FREQ */ 3667 3668 #ifdef arch_scale_freq_capacity 3669 # ifndef arch_scale_freq_invariant 3670 # define arch_scale_freq_invariant() true 3671 # endif 3672 #else 3673 # define arch_scale_freq_invariant() false 3674 #endif 3675 3676 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs, 3677 unsigned long *min, 3678 unsigned long *max); 3679 3680 unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual, 3681 unsigned long min, 3682 unsigned long max); 3683 3684 3685 /* 3686 * Verify the fitness of task @p to run on @cpu taking into account the 3687 * CPU original capacity and the runtime/deadline ratio of the task. 3688 * 3689 * The function will return true if the original capacity of @cpu is 3690 * greater than or equal to task's deadline density right shifted by 3691 * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise. 3692 */ 3693 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu) 3694 { 3695 unsigned long cap = arch_scale_cpu_capacity(cpu); 3696 3697 return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT); 3698 } 3699 3700 static inline unsigned long cpu_bw_dl(struct rq *rq) 3701 { 3702 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT; 3703 } 3704 3705 static inline unsigned long cpu_util_dl(struct rq *rq) 3706 { 3707 return READ_ONCE(rq->avg_dl.util_avg); 3708 } 3709 3710 3711 extern unsigned long cpu_util_cfs(int cpu); 3712 extern unsigned long cpu_util_cfs_boost(int cpu); 3713 3714 static inline unsigned long cpu_util_rt(struct rq *rq) 3715 { 3716 return READ_ONCE(rq->avg_rt.util_avg); 3717 } 3718 3719 #ifdef CONFIG_UCLAMP_TASK 3720 3721 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id); 3722 3723 /* 3724 * When uclamp is compiled in, the aggregation at rq level is 'turned off' 3725 * by default in the fast path and only gets turned on once userspace performs 3726 * an operation that requires it. 3727 * 3728 * Returns true if userspace opted-in to use uclamp and aggregation at rq level 3729 * hence is active. 3730 */ 3731 static inline bool uclamp_is_used(void) 3732 { 3733 return static_branch_likely(&sched_uclamp_used); 3734 } 3735 3736 /* 3737 * Enabling static branches would get the cpus_read_lock(), 3738 * check whether uclamp_is_used before enable it to avoid always 3739 * calling cpus_read_lock(). Because we never disable this 3740 * static key once enable it. 3741 */ 3742 static inline void sched_uclamp_enable(void) 3743 { 3744 if (!uclamp_is_used()) 3745 static_branch_enable(&sched_uclamp_used); 3746 } 3747 3748 static inline unsigned long uclamp_rq_get(struct rq *rq, 3749 enum uclamp_id clamp_id) 3750 { 3751 return READ_ONCE(rq->uclamp[clamp_id].value); 3752 } 3753 3754 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, 3755 unsigned int value) 3756 { 3757 WRITE_ONCE(rq->uclamp[clamp_id].value, value); 3758 } 3759 3760 static inline bool uclamp_rq_is_idle(struct rq *rq) 3761 { 3762 return rq->uclamp_flags & UCLAMP_FLAG_IDLE; 3763 } 3764 3765 /* Is the rq being capped/throttled by uclamp_max? */ 3766 static inline bool uclamp_rq_is_capped(struct rq *rq) 3767 { 3768 unsigned long rq_util; 3769 unsigned long max_util; 3770 3771 if (!uclamp_is_used()) 3772 return false; 3773 3774 rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq); 3775 max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value); 3776 3777 return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util; 3778 } 3779 3780 #define for_each_clamp_id(clamp_id) \ 3781 for ((clamp_id) = 0; (clamp_id) < UCLAMP_CNT; (clamp_id)++) 3782 3783 extern unsigned int sysctl_sched_uclamp_util_min_rt_default; 3784 3785 3786 static inline unsigned int uclamp_none(enum uclamp_id clamp_id) 3787 { 3788 if (clamp_id == UCLAMP_MIN) 3789 return 0; 3790 return SCHED_CAPACITY_SCALE; 3791 } 3792 3793 /* Integer rounded range for each bucket */ 3794 #define UCLAMP_BUCKET_DELTA DIV_ROUND_CLOSEST(SCHED_CAPACITY_SCALE, UCLAMP_BUCKETS) 3795 3796 static inline unsigned int uclamp_bucket_id(unsigned int clamp_value) 3797 { 3798 return min_t(unsigned int, clamp_value / UCLAMP_BUCKET_DELTA, UCLAMP_BUCKETS - 1); 3799 } 3800 3801 static inline void 3802 uclamp_se_set(struct uclamp_se *uc_se, unsigned int value, bool user_defined) 3803 { 3804 uc_se->value = value; 3805 uc_se->bucket_id = uclamp_bucket_id(value); 3806 uc_se->user_defined = user_defined; 3807 } 3808 3809 #else /* !CONFIG_UCLAMP_TASK: */ 3810 3811 static inline unsigned long 3812 uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id) 3813 { 3814 if (clamp_id == UCLAMP_MIN) 3815 return 0; 3816 3817 return SCHED_CAPACITY_SCALE; 3818 } 3819 3820 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; } 3821 3822 static inline bool uclamp_is_used(void) 3823 { 3824 return false; 3825 } 3826 3827 static inline void sched_uclamp_enable(void) {} 3828 3829 static inline unsigned long 3830 uclamp_rq_get(struct rq *rq, enum uclamp_id clamp_id) 3831 { 3832 if (clamp_id == UCLAMP_MIN) 3833 return 0; 3834 3835 return SCHED_CAPACITY_SCALE; 3836 } 3837 3838 static inline void 3839 uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, unsigned int value) 3840 { 3841 } 3842 3843 static inline bool uclamp_rq_is_idle(struct rq *rq) 3844 { 3845 return false; 3846 } 3847 3848 #endif /* !CONFIG_UCLAMP_TASK */ 3849 3850 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 3851 3852 static inline unsigned long cpu_util_irq(struct rq *rq) 3853 { 3854 return READ_ONCE(rq->avg_irq.util_avg); 3855 } 3856 3857 static inline 3858 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 3859 { 3860 util *= (max - irq); 3861 util /= max; 3862 3863 return util; 3864 3865 } 3866 3867 #else /* !CONFIG_HAVE_SCHED_AVG_IRQ: */ 3868 3869 static inline unsigned long cpu_util_irq(struct rq *rq) 3870 { 3871 return 0; 3872 } 3873 3874 static inline 3875 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 3876 { 3877 return util; 3878 } 3879 3880 #endif /* !CONFIG_HAVE_SCHED_AVG_IRQ */ 3881 3882 extern void __setparam_fair(struct task_struct *p, const struct sched_attr *attr); 3883 3884 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) 3885 3886 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus))) 3887 3888 DECLARE_STATIC_KEY_FALSE(sched_energy_present); 3889 3890 static inline bool sched_energy_enabled(void) 3891 { 3892 return static_branch_unlikely(&sched_energy_present); 3893 } 3894 3895 #else /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL): */ 3896 3897 #define perf_domain_span(pd) NULL 3898 3899 static inline bool sched_energy_enabled(void) { return false; } 3900 3901 #endif /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */ 3902 3903 #ifdef CONFIG_MEMBARRIER 3904 3905 /* 3906 * The scheduler provides memory barriers required by membarrier between: 3907 * - prior user-space memory accesses and store to rq->membarrier_state, 3908 * - store to rq->membarrier_state and following user-space memory accesses. 3909 * In the same way it provides those guarantees around store to rq->curr. 3910 */ 3911 static inline void membarrier_switch_mm(struct rq *rq, 3912 struct mm_struct *prev_mm, 3913 struct mm_struct *next_mm) 3914 { 3915 int membarrier_state; 3916 3917 if (prev_mm == next_mm) 3918 return; 3919 3920 membarrier_state = atomic_read(&next_mm->membarrier_state); 3921 if (READ_ONCE(rq->membarrier_state) == membarrier_state) 3922 return; 3923 3924 WRITE_ONCE(rq->membarrier_state, membarrier_state); 3925 } 3926 3927 #else /* !CONFIG_MEMBARRIER: */ 3928 3929 static inline void membarrier_switch_mm(struct rq *rq, 3930 struct mm_struct *prev_mm, 3931 struct mm_struct *next_mm) 3932 { 3933 } 3934 3935 #endif /* !CONFIG_MEMBARRIER */ 3936 3937 static inline bool is_per_cpu_kthread(struct task_struct *p) 3938 { 3939 if (!(p->flags & PF_KTHREAD)) 3940 return false; 3941 3942 if (p->nr_cpus_allowed != 1) 3943 return false; 3944 3945 return true; 3946 } 3947 3948 extern void swake_up_all_locked(struct swait_queue_head *q); 3949 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait); 3950 3951 extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags); 3952 3953 #ifdef CONFIG_PREEMPT_DYNAMIC 3954 extern int preempt_dynamic_mode; 3955 extern int sched_dynamic_mode(const char *str); 3956 extern void sched_dynamic_update(int mode); 3957 #endif 3958 extern const char *preempt_modes[]; 3959 3960 #ifdef CONFIG_SCHED_MM_CID 3961 3962 static __always_inline bool cid_on_cpu(unsigned int cid) 3963 { 3964 return cid & MM_CID_ONCPU; 3965 } 3966 3967 static __always_inline bool cid_in_transit(unsigned int cid) 3968 { 3969 return cid & MM_CID_TRANSIT; 3970 } 3971 3972 static __always_inline unsigned int cpu_cid_to_cid(unsigned int cid) 3973 { 3974 return cid & ~MM_CID_ONCPU; 3975 } 3976 3977 static __always_inline unsigned int cid_to_cpu_cid(unsigned int cid) 3978 { 3979 return cid | MM_CID_ONCPU; 3980 } 3981 3982 static __always_inline unsigned int cid_to_transit_cid(unsigned int cid) 3983 { 3984 return cid | MM_CID_TRANSIT; 3985 } 3986 3987 static __always_inline unsigned int cid_from_transit_cid(unsigned int cid) 3988 { 3989 return cid & ~MM_CID_TRANSIT; 3990 } 3991 3992 static __always_inline bool cid_on_task(unsigned int cid) 3993 { 3994 /* True if none of the MM_CID_ONCPU, MM_CID_TRANSIT, MM_CID_UNSET bits is set */ 3995 return cid < MM_CID_TRANSIT; 3996 } 3997 3998 static __always_inline void mm_drop_cid(struct mm_struct *mm, unsigned int cid) 3999 { 4000 clear_bit(cid, mm_cidmask(mm)); 4001 } 4002 4003 static __always_inline void mm_unset_cid_on_task(struct task_struct *t) 4004 { 4005 unsigned int cid = t->mm_cid.cid; 4006 4007 t->mm_cid.cid = MM_CID_UNSET; 4008 if (cid_on_task(cid)) 4009 mm_drop_cid(t->mm, cid); 4010 } 4011 4012 static __always_inline void mm_drop_cid_on_cpu(struct mm_struct *mm, struct mm_cid_pcpu *pcp) 4013 { 4014 /* Clear the ONCPU bit, but do not set UNSET in the per CPU storage */ 4015 if (cid_on_cpu(pcp->cid)) { 4016 pcp->cid = cpu_cid_to_cid(pcp->cid); 4017 mm_drop_cid(mm, pcp->cid); 4018 } 4019 } 4020 4021 static inline unsigned int __mm_get_cid(struct mm_struct *mm, unsigned int max_cids) 4022 { 4023 unsigned int cid = find_first_zero_bit(mm_cidmask(mm), max_cids); 4024 4025 if (cid >= max_cids) 4026 return MM_CID_UNSET; 4027 if (test_and_set_bit(cid, mm_cidmask(mm))) 4028 return MM_CID_UNSET; 4029 return cid; 4030 } 4031 4032 static inline unsigned int mm_get_cid(struct mm_struct *mm) 4033 { 4034 unsigned int cid = __mm_get_cid(mm, READ_ONCE(mm->mm_cid.max_cids)); 4035 4036 while (cid == MM_CID_UNSET) { 4037 cpu_relax(); 4038 cid = __mm_get_cid(mm, num_possible_cpus()); 4039 } 4040 return cid; 4041 } 4042 4043 static inline unsigned int mm_cid_converge(struct mm_struct *mm, unsigned int orig_cid, 4044 unsigned int max_cids) 4045 { 4046 unsigned int new_cid, cid = cpu_cid_to_cid(orig_cid); 4047 4048 /* Is it in the optimal CID space? */ 4049 if (likely(cid < max_cids)) 4050 return orig_cid; 4051 4052 /* Try to find one in the optimal space. Otherwise keep the provided. */ 4053 new_cid = __mm_get_cid(mm, max_cids); 4054 if (new_cid != MM_CID_UNSET) { 4055 mm_drop_cid(mm, cid); 4056 /* Preserve the ONCPU mode of the original CID */ 4057 return new_cid | (orig_cid & MM_CID_ONCPU); 4058 } 4059 return orig_cid; 4060 } 4061 4062 static __always_inline void mm_cid_update_task_cid(struct task_struct *t, unsigned int cid) 4063 { 4064 if (t->mm_cid.cid != cid) { 4065 t->mm_cid.cid = cid; 4066 rseq_sched_set_ids_changed(t); 4067 } 4068 } 4069 4070 static __always_inline void mm_cid_update_pcpu_cid(struct mm_struct *mm, unsigned int cid) 4071 { 4072 __this_cpu_write(mm->mm_cid.pcpu->cid, cid); 4073 } 4074 4075 static __always_inline void mm_cid_from_cpu(struct task_struct *t, unsigned int cpu_cid, 4076 unsigned int mode) 4077 { 4078 unsigned int max_cids, tcid = t->mm_cid.cid; 4079 struct mm_struct *mm = t->mm; 4080 4081 max_cids = READ_ONCE(mm->mm_cid.max_cids); 4082 /* Optimize for the common case where both have the ONCPU bit set */ 4083 if (likely(cid_on_cpu(cpu_cid & tcid))) { 4084 if (likely(cpu_cid_to_cid(cpu_cid) < max_cids)) { 4085 mm_cid_update_task_cid(t, cpu_cid); 4086 return; 4087 } 4088 /* Try to converge into the optimal CID space */ 4089 cpu_cid = mm_cid_converge(mm, cpu_cid, max_cids); 4090 } else { 4091 /* Hand over or drop the task owned CID */ 4092 if (cid_on_task(tcid)) { 4093 if (cid_on_cpu(cpu_cid)) 4094 mm_unset_cid_on_task(t); 4095 else 4096 cpu_cid = cid_to_cpu_cid(tcid); 4097 } 4098 /* Still nothing, allocate a new one */ 4099 if (!cid_on_cpu(cpu_cid)) 4100 cpu_cid = cid_to_cpu_cid(mm_get_cid(mm)); 4101 4102 /* Handle the transition mode flag if required */ 4103 if (mode & MM_CID_TRANSIT) 4104 cpu_cid = cpu_cid_to_cid(cpu_cid) | MM_CID_TRANSIT; 4105 } 4106 mm_cid_update_pcpu_cid(mm, cpu_cid); 4107 mm_cid_update_task_cid(t, cpu_cid); 4108 } 4109 4110 static __always_inline void mm_cid_from_task(struct task_struct *t, unsigned int cpu_cid, 4111 unsigned int mode) 4112 { 4113 unsigned int max_cids, tcid = t->mm_cid.cid; 4114 struct mm_struct *mm = t->mm; 4115 4116 max_cids = READ_ONCE(mm->mm_cid.max_cids); 4117 /* Optimize for the common case, where both have the ONCPU bit clear */ 4118 if (likely(cid_on_task(tcid | cpu_cid))) { 4119 if (likely(tcid < max_cids)) { 4120 mm_cid_update_pcpu_cid(mm, tcid); 4121 return; 4122 } 4123 /* Try to converge into the optimal CID space */ 4124 tcid = mm_cid_converge(mm, tcid, max_cids); 4125 } else { 4126 /* Hand over or drop the CPU owned CID */ 4127 if (cid_on_cpu(cpu_cid)) { 4128 if (cid_on_task(tcid)) 4129 mm_drop_cid_on_cpu(mm, this_cpu_ptr(mm->mm_cid.pcpu)); 4130 else 4131 tcid = cpu_cid_to_cid(cpu_cid); 4132 } 4133 /* Still nothing, allocate a new one */ 4134 if (!cid_on_task(tcid)) 4135 tcid = mm_get_cid(mm); 4136 /* Set the transition mode flag if required */ 4137 tcid |= mode & MM_CID_TRANSIT; 4138 } 4139 mm_cid_update_pcpu_cid(mm, tcid); 4140 mm_cid_update_task_cid(t, tcid); 4141 } 4142 4143 static __always_inline void mm_cid_schedin(struct task_struct *next) 4144 { 4145 struct mm_struct *mm = next->mm; 4146 unsigned int cpu_cid, mode; 4147 4148 if (!next->mm_cid.active) 4149 return; 4150 4151 cpu_cid = __this_cpu_read(mm->mm_cid.pcpu->cid); 4152 mode = READ_ONCE(mm->mm_cid.mode); 4153 if (likely(!cid_on_cpu(mode))) 4154 mm_cid_from_task(next, cpu_cid, mode); 4155 else 4156 mm_cid_from_cpu(next, cpu_cid, mode); 4157 } 4158 4159 static __always_inline void mm_cid_schedout(struct task_struct *prev) 4160 { 4161 struct mm_struct *mm = prev->mm; 4162 unsigned int mode, cid; 4163 4164 /* During mode transitions CIDs are temporary and need to be dropped */ 4165 if (likely(!cid_in_transit(prev->mm_cid.cid))) 4166 return; 4167 4168 mode = READ_ONCE(mm->mm_cid.mode); 4169 cid = cid_from_transit_cid(prev->mm_cid.cid); 4170 4171 /* 4172 * If transition mode is done, transfer ownership when the CID is 4173 * within the convergence range to optimize the next schedule in. 4174 */ 4175 if (!cid_in_transit(mode) && cid < READ_ONCE(mm->mm_cid.max_cids)) { 4176 if (cid_on_cpu(mode)) 4177 cid = cid_to_cpu_cid(cid); 4178 4179 /* Update both so that the next schedule in goes into the fast path */ 4180 mm_cid_update_pcpu_cid(mm, cid); 4181 prev->mm_cid.cid = cid; 4182 } else { 4183 mm_drop_cid(mm, cid); 4184 prev->mm_cid.cid = MM_CID_UNSET; 4185 } 4186 } 4187 4188 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next) 4189 { 4190 mm_cid_schedout(prev); 4191 mm_cid_schedin(next); 4192 } 4193 4194 #else /* !CONFIG_SCHED_MM_CID: */ 4195 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next) { } 4196 #endif /* !CONFIG_SCHED_MM_CID */ 4197 4198 #ifdef CONFIG_SCHED_CACHE 4199 DECLARE_STATIC_KEY_FALSE(sched_cache_present); 4200 DECLARE_STATIC_KEY_FALSE(sched_cache_active); 4201 extern int sysctl_sched_cache_user; 4202 extern unsigned int llc_aggr_tolerance; 4203 extern unsigned int llc_epoch_period; 4204 extern unsigned int llc_epoch_affinity_timeout; 4205 extern unsigned int llc_imb_pct; 4206 extern unsigned int llc_overaggr_pct; 4207 4208 static inline bool sched_cache_enabled(void) 4209 { 4210 return static_branch_unlikely(&sched_cache_active); 4211 } 4212 4213 extern void sched_cache_active_set(void); 4214 4215 #endif 4216 4217 void sched_domains_free_llc_id(int cpu); 4218 4219 extern void init_sched_mm(struct task_struct *p); 4220 4221 extern u64 avg_vruntime(struct cfs_rq *cfs_rq); 4222 extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se); 4223 static inline 4224 void move_queued_task_locked(struct rq *src_rq, struct rq *dst_rq, struct task_struct *task) 4225 { 4226 lockdep_assert_rq_held(src_rq); 4227 lockdep_assert_rq_held(dst_rq); 4228 4229 deactivate_task(src_rq, task, 0); 4230 set_task_cpu(task, dst_rq->cpu); 4231 activate_task(dst_rq, task, 0); 4232 wakeup_preempt(dst_rq, task, 0); 4233 } 4234 4235 static inline 4236 bool task_is_pushable(struct rq *rq, struct task_struct *p, int cpu) 4237 { 4238 if (!task_on_cpu(rq, p) && 4239 cpumask_test_cpu(cpu, &p->cpus_mask)) 4240 return true; 4241 4242 return false; 4243 } 4244 4245 #ifdef CONFIG_RT_MUTEXES 4246 4247 static inline int __rt_effective_prio(struct task_struct *pi_task, int prio) 4248 { 4249 if (pi_task) 4250 prio = min(prio, pi_task->prio); 4251 4252 return prio; 4253 } 4254 4255 static inline int rt_effective_prio(struct task_struct *p, int prio) 4256 { 4257 struct task_struct *pi_task = rt_mutex_get_top_task(p); 4258 4259 return __rt_effective_prio(pi_task, prio); 4260 } 4261 4262 #else /* !CONFIG_RT_MUTEXES: */ 4263 4264 static inline int rt_effective_prio(struct task_struct *p, int prio) 4265 { 4266 return prio; 4267 } 4268 4269 #endif /* !CONFIG_RT_MUTEXES */ 4270 4271 extern int __sched_setscheduler(struct task_struct *p, const struct sched_attr *attr, bool user, bool pi); 4272 extern int __sched_setaffinity(struct task_struct *p, struct affinity_context *ctx); 4273 extern const struct sched_class *__setscheduler_class(int policy, int prio); 4274 extern void set_load_weight(struct task_struct *p, bool update_load); 4275 extern void enqueue_task(struct rq *rq, struct task_struct *p, int flags); 4276 extern bool dequeue_task(struct rq *rq, struct task_struct *p, int flags); 4277 4278 extern struct balance_callback *splice_balance_callbacks(struct rq *rq); 4279 4280 extern void __balance_callbacks(struct rq *rq, struct rq_flags *rf); 4281 extern void balance_callbacks(struct rq *rq, struct balance_callback *head); 4282 4283 /* 4284 * The 'sched_change' pattern is the safe, easy and slow way of changing a 4285 * task's scheduling properties. It dequeues a task, such that the scheduler 4286 * is fully unaware of it; at which point its properties can be modified; 4287 * after which it is enqueued again. 4288 * 4289 * Typically this must be called while holding task_rq_lock, since most/all 4290 * properties are serialized under those locks. There are currently two 4291 * exceptions to this rule in sched/ext which only hold rq->lock: scx_bypass() 4292 * and rq_offline_scx(). 4293 */ 4294 4295 /* 4296 * This structure is a temporary, used to preserve/convey the queueing state 4297 * of the task between sched_change_begin() and sched_change_end(). Ensuring 4298 * the task's queueing state is idempotent across the operation. 4299 */ 4300 struct sched_change_ctx { 4301 u64 prio; 4302 struct task_struct *p; 4303 const struct sched_class *class; 4304 int flags; 4305 bool queued; 4306 bool running; 4307 }; 4308 4309 struct sched_change_ctx *sched_change_begin(struct task_struct *p, unsigned int flags); 4310 void sched_change_end(struct sched_change_ctx *ctx); 4311 4312 DEFINE_CLASS(sched_change, struct sched_change_ctx *, 4313 sched_change_end(_T), 4314 sched_change_begin(p, flags), 4315 struct task_struct *p, unsigned int flags) 4316 4317 DEFINE_CLASS_IS_UNCONDITIONAL(sched_change) 4318 4319 #include "ext/ext.h" 4320 4321 #ifdef CONFIG_PREFERRED_CPU 4322 void sched_push_current_non_preferred_cpu(struct rq *rq); 4323 #else /* !CONFIG_PREFERRED_CPU */ 4324 static inline void sched_push_current_non_preferred_cpu(struct rq *rq) { } 4325 #endif 4326 4327 #endif /* _KERNEL_SCHED_SCHED_H */ 4328