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); 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); 424 425 static inline bool dl_server_active(struct sched_dl_entity *dl_se) 426 { 427 return dl_se->dl_server_active; 428 } 429 430 #ifdef CONFIG_CGROUP_SCHED 431 432 extern struct list_head task_groups; 433 434 #ifdef CONFIG_GROUP_SCHED_BANDWIDTH 435 extern const u64 max_bw_quota_period_us; 436 437 /* 438 * default period for group bandwidth. 439 * default: 0.1s, units: microseconds 440 */ 441 static inline u64 default_bw_period_us(void) 442 { 443 return 100000ULL; 444 } 445 #endif /* CONFIG_GROUP_SCHED_BANDWIDTH */ 446 447 struct cfs_bandwidth { 448 #ifdef CONFIG_CFS_BANDWIDTH 449 raw_spinlock_t lock; 450 ktime_t period; 451 u64 quota; 452 u64 runtime; 453 u64 burst; 454 u64 runtime_snap; 455 s64 hierarchical_quota; 456 457 u8 idle; 458 u8 period_active; 459 u8 slack_started; 460 struct hrtimer period_timer; 461 struct hrtimer slack_timer; 462 struct list_head throttled_cfs_rq; 463 464 /* Statistics: */ 465 int nr_periods; 466 int nr_throttled; 467 int nr_burst; 468 u64 throttled_time; 469 u64 burst_time; 470 #endif /* CONFIG_CFS_BANDWIDTH */ 471 }; 472 473 /* Task group related information */ 474 struct task_group { 475 struct cgroup_subsys_state css; 476 477 #ifdef CONFIG_GROUP_SCHED_WEIGHT 478 /* A positive value indicates that this is a SCHED_IDLE group. */ 479 int idle; 480 #endif 481 482 #ifdef CONFIG_FAIR_GROUP_SCHED 483 /* schedulable entities of this group on each CPU */ 484 struct sched_entity **se; 485 /* runqueue "owned" by this group on each CPU */ 486 struct cfs_rq **cfs_rq; 487 unsigned long shares; 488 /* 489 * load_avg can be heavily contended at clock tick time, so put 490 * it in its own cache-line separated from the fields above which 491 * will also be accessed at each tick. 492 */ 493 atomic_long_t load_avg ____cacheline_aligned; 494 #endif /* CONFIG_FAIR_GROUP_SCHED */ 495 496 #ifdef CONFIG_RT_GROUP_SCHED 497 struct sched_rt_entity **rt_se; 498 struct rt_rq **rt_rq; 499 500 struct rt_bandwidth rt_bandwidth; 501 #endif 502 503 struct scx_task_group scx; 504 505 struct rcu_head rcu; 506 struct list_head list; 507 508 struct task_group *parent; 509 struct list_head siblings; 510 struct list_head children; 511 512 #ifdef CONFIG_SCHED_AUTOGROUP 513 struct autogroup *autogroup; 514 #endif 515 516 struct cfs_bandwidth cfs_bandwidth; 517 518 #ifdef CONFIG_UCLAMP_TASK_GROUP 519 /* The two decimal precision [%] value requested from user-space */ 520 unsigned int uclamp_pct[UCLAMP_CNT]; 521 /* Clamp values requested for a task group */ 522 struct uclamp_se uclamp_req[UCLAMP_CNT]; 523 /* Effective clamp values used for a task group */ 524 struct uclamp_se uclamp[UCLAMP_CNT]; 525 #endif 526 527 }; 528 529 #ifdef CONFIG_GROUP_SCHED_WEIGHT 530 #define ROOT_TASK_GROUP_LOAD NICE_0_LOAD 531 532 /* 533 * A weight of 0 or 1 can cause arithmetics problems. 534 * A weight of a cfs_rq is the sum of weights of which entities 535 * are queued on this cfs_rq, so a weight of a entity should not be 536 * too large, so as the shares value of a task group. 537 * (The default weight is 1024 - so there's no practical 538 * limitation from this.) 539 */ 540 #define MIN_SHARES (1UL << 1) 541 #define MAX_SHARES (1UL << 18) 542 #endif 543 544 typedef int (*tg_visitor)(struct task_group *, void *); 545 546 extern int walk_tg_tree_from(struct task_group *from, 547 tg_visitor down, tg_visitor up, void *data); 548 549 /* 550 * Iterate the full tree, calling @down when first entering a node and @up when 551 * leaving it for the final time. 552 * 553 * Caller must hold rcu_lock or sufficient equivalent. 554 */ 555 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data) 556 { 557 return walk_tg_tree_from(&root_task_group, down, up, data); 558 } 559 560 static inline struct task_group *css_tg(struct cgroup_subsys_state *css) 561 { 562 return css ? container_of(css, struct task_group, css) : NULL; 563 } 564 565 extern int tg_nop(struct task_group *tg, void *data); 566 567 #ifdef CONFIG_FAIR_GROUP_SCHED 568 extern void free_fair_sched_group(struct task_group *tg); 569 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent); 570 extern void online_fair_sched_group(struct task_group *tg); 571 extern void unregister_fair_sched_group(struct task_group *tg); 572 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 573 static inline void free_fair_sched_group(struct task_group *tg) { } 574 static inline int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) 575 { 576 return 1; 577 } 578 static inline void online_fair_sched_group(struct task_group *tg) { } 579 static inline void unregister_fair_sched_group(struct task_group *tg) { } 580 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 581 582 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, 583 struct sched_entity *se, int cpu, 584 struct sched_entity *parent); 585 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b, struct cfs_bandwidth *parent); 586 587 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b); 588 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b); 589 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq); 590 extern bool cfs_task_bw_constrained(struct task_struct *p); 591 592 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, 593 struct sched_rt_entity *rt_se, int cpu, 594 struct sched_rt_entity *parent); 595 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us); 596 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us); 597 extern long sched_group_rt_runtime(struct task_group *tg); 598 extern long sched_group_rt_period(struct task_group *tg); 599 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk); 600 601 extern struct task_group *sched_create_group(struct task_group *parent); 602 extern void sched_online_group(struct task_group *tg, 603 struct task_group *parent); 604 extern void sched_destroy_group(struct task_group *tg); 605 extern void sched_release_group(struct task_group *tg); 606 607 extern void sched_move_task(struct task_struct *tsk, bool for_autogroup); 608 609 #ifdef CONFIG_FAIR_GROUP_SCHED 610 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); 611 612 extern int sched_group_set_idle(struct task_group *tg, long idle); 613 614 extern void set_task_rq_fair(struct sched_entity *se, 615 struct cfs_rq *prev, struct cfs_rq *next); 616 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 617 static inline int sched_group_set_shares(struct task_group *tg, unsigned long shares) { return 0; } 618 static inline int sched_group_set_idle(struct task_group *tg, long idle) { return 0; } 619 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 620 621 #else /* !CONFIG_CGROUP_SCHED: */ 622 623 struct cfs_bandwidth { }; 624 625 static inline bool cfs_task_bw_constrained(struct task_struct *p) { return false; } 626 627 #endif /* !CONFIG_CGROUP_SCHED */ 628 629 extern void unregister_rt_sched_group(struct task_group *tg); 630 extern void free_rt_sched_group(struct task_group *tg); 631 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent); 632 633 /* 634 * u64_u32_load/u64_u32_store 635 * 636 * Use a copy of a u64 value to protect against data race. This is only 637 * applicable for 32-bits architectures. 638 */ 639 #ifdef CONFIG_64BIT 640 # define u64_u32_load_copy(var, copy) var 641 # define u64_u32_store_copy(var, copy, val) (var = val) 642 #else 643 # define u64_u32_load_copy(var, copy) \ 644 ({ \ 645 u64 __val, __val_copy; \ 646 do { \ 647 __val_copy = copy; \ 648 /* \ 649 * paired with u64_u32_store_copy(), ordering access \ 650 * to var and copy. \ 651 */ \ 652 smp_rmb(); \ 653 __val = var; \ 654 } while (__val != __val_copy); \ 655 __val; \ 656 }) 657 # define u64_u32_store_copy(var, copy, val) \ 658 do { \ 659 typeof(val) __val = (val); \ 660 var = __val; \ 661 /* \ 662 * paired with u64_u32_load_copy(), ordering access to var and \ 663 * copy. \ 664 */ \ 665 smp_wmb(); \ 666 copy = __val; \ 667 } while (0) 668 #endif 669 # define u64_u32_load(var) u64_u32_load_copy(var, var##_copy) 670 # define u64_u32_store(var, val) u64_u32_store_copy(var, var##_copy, val) 671 672 struct balance_callback { 673 struct balance_callback *next; 674 void (*func)(struct rq *rq); 675 }; 676 677 /* Fair scheduling SCHED_{NORMAL,BATCH,IDLE} related fields in a runqueue: */ 678 struct cfs_rq { 679 struct load_weight load; 680 unsigned int nr_queued; 681 unsigned int h_nr_queued; /* SCHED_{NORMAL,BATCH,IDLE} */ 682 unsigned int h_nr_runnable; /* SCHED_{NORMAL,BATCH,IDLE} */ 683 unsigned int h_nr_idle; /* SCHED_IDLE */ 684 685 s64 sum_w_vruntime; 686 u64 sum_weight; 687 688 u64 zero_vruntime; 689 #ifdef CONFIG_SCHED_CORE 690 unsigned int forceidle_seq; 691 u64 zero_vruntime_fi; 692 #endif 693 694 struct rb_root_cached tasks_timeline; 695 696 /* 697 * 'curr' points to the currently running entity on this cfs_rq. 698 * It is set to NULL otherwise (i.e when none are currently running). 699 */ 700 struct sched_entity *curr; 701 struct sched_entity *next; 702 703 /* 704 * CFS load tracking 705 */ 706 struct sched_avg avg; 707 #ifndef CONFIG_64BIT 708 u64 last_update_time_copy; 709 #endif 710 struct { 711 raw_spinlock_t lock ____cacheline_aligned; 712 int nr; 713 unsigned long load_avg; 714 unsigned long util_avg; 715 unsigned long runnable_avg; 716 } removed; 717 718 #ifdef CONFIG_FAIR_GROUP_SCHED 719 u64 last_update_tg_load_avg; 720 unsigned long tg_load_avg_contrib; 721 long propagate; 722 long prop_runnable_sum; 723 724 /* 725 * h_load = weight * f(tg) 726 * 727 * Where f(tg) is the recursive weight fraction assigned to 728 * this group. 729 */ 730 unsigned long h_load; 731 u64 last_h_load_update; 732 struct sched_entity *h_load_next; 733 734 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */ 735 736 /* 737 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in 738 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities 739 * (like users, containers etc.) 740 * 741 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU. 742 * This list is used during load balance. 743 */ 744 int on_list; 745 struct list_head leaf_cfs_rq_list; 746 struct task_group *tg; /* Group that "owns" this runqueue */ 747 748 /* Locally cached copy of our task_group's idle value */ 749 int idle; 750 751 # ifdef CONFIG_CFS_BANDWIDTH 752 int runtime_enabled; 753 s64 runtime_remaining; 754 755 u64 throttled_pelt_idle; 756 # ifndef CONFIG_64BIT 757 u64 throttled_pelt_idle_copy; 758 # endif 759 u64 throttled_clock; 760 u64 throttled_clock_pelt; 761 u64 throttled_clock_pelt_time; 762 u64 throttled_clock_self; 763 u64 throttled_clock_self_time; 764 bool throttled:1; 765 bool pelt_clock_throttled:1; 766 int throttle_count; 767 struct list_head throttled_list; 768 struct list_head throttled_csd_list; 769 struct list_head throttled_limbo_list; 770 # endif /* CONFIG_CFS_BANDWIDTH */ 771 #endif /* CONFIG_FAIR_GROUP_SCHED */ 772 }; 773 774 #ifdef CONFIG_SCHED_CLASS_EXT 775 /* scx_rq->flags, protected by the rq lock */ 776 enum scx_rq_flags { 777 /* 778 * A hotplugged CPU starts scheduling before rq_online_scx(). Track 779 * ops.cpu_on/offline() state so that ops.enqueue/dispatch() are called 780 * only while the BPF scheduler considers the CPU to be online. 781 */ 782 SCX_RQ_ONLINE = 1 << 0, 783 SCX_RQ_CAN_STOP_TICK = 1 << 1, 784 SCX_RQ_BAL_KEEP = 1 << 3, /* balance decided to keep current */ 785 SCX_RQ_BYPASSING = 1 << 4, 786 SCX_RQ_CLK_VALID = 1 << 5, /* RQ clock is fresh and valid */ 787 SCX_RQ_BAL_CB_PENDING = 1 << 6, /* must queue a cb after dispatching */ 788 789 SCX_RQ_IN_WAKEUP = 1 << 16, 790 SCX_RQ_IN_BALANCE = 1 << 17, 791 }; 792 793 struct scx_rq { 794 struct scx_dispatch_q local_dsq; 795 struct list_head runnable_list; /* runnable tasks on this rq */ 796 struct list_head ddsp_deferred_locals; /* deferred ddsps from enq */ 797 unsigned long ops_qseq; 798 u64 extra_enq_flags; /* see move_task_to_local_dsq() */ 799 u32 nr_running; 800 u32 cpuperf_target; /* [0, SCHED_CAPACITY_SCALE] */ 801 bool cpu_released; 802 u32 flags; 803 u64 clock; /* current per-rq clock -- see scx_bpf_now() */ 804 cpumask_var_t cpus_to_kick; 805 cpumask_var_t cpus_to_kick_if_idle; 806 cpumask_var_t cpus_to_preempt; 807 cpumask_var_t cpus_to_wait; 808 cpumask_var_t cpus_to_sync; 809 bool kick_sync_pending; 810 unsigned long kick_sync; 811 local_t reenq_local_deferred; 812 struct balance_callback deferred_bal_cb; 813 struct balance_callback kick_sync_bal_cb; 814 struct irq_work deferred_irq_work; 815 struct irq_work kick_cpus_irq_work; 816 struct scx_dispatch_q bypass_dsq; 817 }; 818 #endif /* CONFIG_SCHED_CLASS_EXT */ 819 820 static inline int rt_bandwidth_enabled(void) 821 { 822 return sysctl_sched_rt_runtime >= 0; 823 } 824 825 /* RT IPI pull logic requires IRQ_WORK */ 826 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP) 827 # define HAVE_RT_PUSH_IPI 828 #endif 829 830 /* Real-Time classes' related field in a runqueue: */ 831 struct rt_rq { 832 struct rt_prio_array active; 833 unsigned int rt_nr_running; 834 unsigned int rr_nr_running; 835 struct { 836 int curr; /* highest queued rt task prio */ 837 int next; /* next highest */ 838 } highest_prio; 839 bool overloaded; 840 struct plist_head pushable_tasks; 841 842 int rt_queued; 843 844 #ifdef CONFIG_RT_GROUP_SCHED 845 int rt_throttled; 846 u64 rt_time; /* consumed RT time, goes up in update_curr_rt */ 847 u64 rt_runtime; /* allotted RT time, "slice" from rt_bandwidth, RT sharing/balancing */ 848 /* Nests inside the rq lock: */ 849 raw_spinlock_t rt_runtime_lock; 850 851 unsigned int rt_nr_boosted; 852 853 struct rq *rq; /* this is always top-level rq, cache? */ 854 #endif 855 #ifdef CONFIG_CGROUP_SCHED 856 struct task_group *tg; /* this tg has "this" rt_rq on given CPU for runnable entities */ 857 #endif 858 }; 859 860 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq) 861 { 862 return rt_rq->rt_queued && rt_rq->rt_nr_running; 863 } 864 865 /* Deadline class' related fields in a runqueue */ 866 struct dl_rq { 867 /* runqueue is an rbtree, ordered by deadline */ 868 struct rb_root_cached root; 869 870 unsigned int dl_nr_running; 871 872 /* 873 * Deadline values of the currently executing and the 874 * earliest ready task on this rq. Caching these facilitates 875 * the decision whether or not a ready but not running task 876 * should migrate somewhere else. 877 */ 878 struct { 879 u64 curr; 880 u64 next; 881 } earliest_dl; 882 883 bool overloaded; 884 885 /* 886 * Tasks on this rq that can be pushed away. They are kept in 887 * an rb-tree, ordered by tasks' deadlines, with caching 888 * of the leftmost (earliest deadline) element. 889 */ 890 struct rb_root_cached pushable_dl_tasks_root; 891 892 /* 893 * "Active utilization" for this runqueue: increased when a 894 * task wakes up (becomes TASK_RUNNING) and decreased when a 895 * task blocks 896 */ 897 u64 running_bw; 898 899 /* 900 * Utilization of the tasks "assigned" to this runqueue (including 901 * the tasks that are in runqueue and the tasks that executed on this 902 * CPU and blocked). Increased when a task moves to this runqueue, and 903 * decreased when the task moves away (migrates, changes scheduling 904 * policy, or terminates). 905 * This is needed to compute the "inactive utilization" for the 906 * runqueue (inactive utilization = this_bw - running_bw). 907 */ 908 u64 this_bw; 909 u64 extra_bw; 910 911 /* 912 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM 913 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB). 914 */ 915 u64 max_bw; 916 917 /* 918 * Inverse of the fraction of CPU utilization that can be reclaimed 919 * by the GRUB algorithm. 920 */ 921 u64 bw_ratio; 922 }; 923 924 #ifdef CONFIG_FAIR_GROUP_SCHED 925 926 /* An entity is a task if it doesn't "own" a runqueue */ 927 #define entity_is_task(se) (!se->my_q) 928 929 static inline void se_update_runnable(struct sched_entity *se) 930 { 931 if (!entity_is_task(se)) 932 se->runnable_weight = se->my_q->h_nr_runnable; 933 } 934 935 static inline long se_runnable(struct sched_entity *se) 936 { 937 if (se->sched_delayed) 938 return false; 939 940 if (entity_is_task(se)) 941 return !!se->on_rq; 942 else 943 return se->runnable_weight; 944 } 945 946 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 947 948 #define entity_is_task(se) 1 949 950 static inline void se_update_runnable(struct sched_entity *se) { } 951 952 static inline long se_runnable(struct sched_entity *se) 953 { 954 if (se->sched_delayed) 955 return false; 956 957 return !!se->on_rq; 958 } 959 960 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 961 962 /* 963 * XXX we want to get rid of these helpers and use the full load resolution. 964 */ 965 static inline long se_weight(struct sched_entity *se) 966 { 967 return scale_load_down(se->load.weight); 968 } 969 970 971 static inline bool sched_asym_prefer(int a, int b) 972 { 973 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b); 974 } 975 976 struct perf_domain { 977 struct em_perf_domain *em_pd; 978 struct perf_domain *next; 979 struct rcu_head rcu; 980 }; 981 982 /* 983 * We add the notion of a root-domain which will be used to define per-domain 984 * variables. Each exclusive cpuset essentially defines an island domain by 985 * fully partitioning the member CPUs from any other cpuset. Whenever a new 986 * exclusive cpuset is created, we also create and attach a new root-domain 987 * object. 988 * 989 */ 990 struct root_domain { 991 atomic_t refcount; 992 atomic_t rto_count; 993 struct rcu_head rcu; 994 cpumask_var_t span; 995 cpumask_var_t online; 996 997 /* 998 * Indicate pullable load on at least one CPU, e.g: 999 * - More than one runnable task 1000 * - Running task is misfit 1001 */ 1002 bool overloaded; 1003 1004 /* Indicate one or more CPUs over-utilized (tipping point) */ 1005 bool overutilized; 1006 1007 /* 1008 * The bit corresponding to a CPU gets set here if such CPU has more 1009 * than one runnable -deadline task (as it is below for RT tasks). 1010 */ 1011 cpumask_var_t dlo_mask; 1012 atomic_t dlo_count; 1013 struct dl_bw dl_bw; 1014 struct cpudl cpudl; 1015 1016 /* 1017 * Indicate whether a root_domain's dl_bw has been checked or 1018 * updated. It's monotonously increasing value. 1019 * 1020 * Also, some corner cases, like 'wrap around' is dangerous, but given 1021 * that u64 is 'big enough'. So that shouldn't be a concern. 1022 */ 1023 u64 visit_cookie; 1024 1025 #ifdef HAVE_RT_PUSH_IPI 1026 /* 1027 * For IPI pull requests, loop across the rto_mask. 1028 */ 1029 struct irq_work rto_push_work; 1030 raw_spinlock_t rto_lock; 1031 /* These are only updated and read within rto_lock */ 1032 int rto_loop; 1033 int rto_cpu; 1034 /* These atomics are updated outside of a lock */ 1035 atomic_t rto_loop_next; 1036 atomic_t rto_loop_start; 1037 #endif /* HAVE_RT_PUSH_IPI */ 1038 /* 1039 * The "RT overload" flag: it gets set if a CPU has more than 1040 * one runnable RT task. 1041 */ 1042 cpumask_var_t rto_mask; 1043 struct cpupri cpupri; 1044 1045 /* 1046 * NULL-terminated list of performance domains intersecting with the 1047 * CPUs of the rd. Protected by RCU. 1048 */ 1049 struct perf_domain __rcu *pd; 1050 }; 1051 1052 extern void init_defrootdomain(void); 1053 extern int sched_init_domains(const struct cpumask *cpu_map); 1054 extern void rq_attach_root(struct rq *rq, struct root_domain *rd); 1055 extern void sched_get_rd(struct root_domain *rd); 1056 extern void sched_put_rd(struct root_domain *rd); 1057 1058 static inline int get_rd_overloaded(struct root_domain *rd) 1059 { 1060 return READ_ONCE(rd->overloaded); 1061 } 1062 1063 static inline void set_rd_overloaded(struct root_domain *rd, int status) 1064 { 1065 if (get_rd_overloaded(rd) != status) 1066 WRITE_ONCE(rd->overloaded, status); 1067 } 1068 1069 #ifdef HAVE_RT_PUSH_IPI 1070 extern void rto_push_irq_work_func(struct irq_work *work); 1071 #endif 1072 1073 #ifdef CONFIG_UCLAMP_TASK 1074 /* 1075 * struct uclamp_bucket - Utilization clamp bucket 1076 * @value: utilization clamp value for tasks on this clamp bucket 1077 * @tasks: number of RUNNABLE tasks on this clamp bucket 1078 * 1079 * Keep track of how many tasks are RUNNABLE for a given utilization 1080 * clamp value. 1081 */ 1082 struct uclamp_bucket { 1083 unsigned long value : bits_per(SCHED_CAPACITY_SCALE); 1084 unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE); 1085 }; 1086 1087 /* 1088 * struct uclamp_rq - rq's utilization clamp 1089 * @value: currently active clamp values for a rq 1090 * @bucket: utilization clamp buckets affecting a rq 1091 * 1092 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values. 1093 * A clamp value is affecting a rq when there is at least one task RUNNABLE 1094 * (or actually running) with that value. 1095 * 1096 * There are up to UCLAMP_CNT possible different clamp values, currently there 1097 * are only two: minimum utilization and maximum utilization. 1098 * 1099 * All utilization clamping values are MAX aggregated, since: 1100 * - for util_min: we want to run the CPU at least at the max of the minimum 1101 * utilization required by its currently RUNNABLE tasks. 1102 * - for util_max: we want to allow the CPU to run up to the max of the 1103 * maximum utilization allowed by its currently RUNNABLE tasks. 1104 * 1105 * Since on each system we expect only a limited number of different 1106 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track 1107 * the metrics required to compute all the per-rq utilization clamp values. 1108 */ 1109 struct uclamp_rq { 1110 unsigned int value; 1111 struct uclamp_bucket bucket[UCLAMP_BUCKETS]; 1112 }; 1113 1114 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used); 1115 #endif /* CONFIG_UCLAMP_TASK */ 1116 1117 /* 1118 * This is the main, per-CPU runqueue data structure. 1119 * 1120 * Locking rule: those places that want to lock multiple runqueues 1121 * (such as the load balancing or the thread migration code), lock 1122 * acquire operations must be ordered by ascending &runqueue. 1123 */ 1124 struct rq { 1125 /* 1126 * The following members are loaded together, without holding the 1127 * rq->lock, in an extremely hot loop in update_sg_lb_stats() 1128 * (called from pick_next_task()). To reduce cache pollution from 1129 * this operation, they are placed together on this dedicated cache 1130 * line. Even though some of them are frequently modified, they are 1131 * loaded much more frequently than they are stored. 1132 */ 1133 unsigned int nr_running; 1134 #ifdef CONFIG_NUMA_BALANCING 1135 unsigned int nr_numa_running; 1136 unsigned int nr_preferred_running; 1137 #endif 1138 unsigned int ttwu_pending; 1139 unsigned long cpu_capacity; 1140 #ifdef CONFIG_SCHED_PROXY_EXEC 1141 struct task_struct __rcu *donor; /* Scheduling context */ 1142 struct task_struct __rcu *curr; /* Execution context */ 1143 #else 1144 union { 1145 struct task_struct __rcu *donor; /* Scheduler context */ 1146 struct task_struct __rcu *curr; /* Execution context */ 1147 }; 1148 #endif 1149 struct task_struct *idle; 1150 /* padding left here deliberately */ 1151 1152 /* 1153 * The next cacheline holds the (hot) runqueue lock, as well as 1154 * some other less performance-critical fields. 1155 */ 1156 u64 nr_switches ____cacheline_aligned; 1157 1158 /* runqueue lock: */ 1159 raw_spinlock_t __lock; 1160 1161 #ifdef CONFIG_NO_HZ_COMMON 1162 unsigned int nohz_tick_stopped; 1163 atomic_t nohz_flags; 1164 unsigned int has_blocked_load; 1165 unsigned long last_blocked_load_update_tick; 1166 call_single_data_t nohz_csd; 1167 #endif /* CONFIG_NO_HZ_COMMON */ 1168 1169 #ifdef CONFIG_UCLAMP_TASK 1170 /* Utilization clamp values based on CPU's RUNNABLE tasks */ 1171 struct uclamp_rq uclamp[UCLAMP_CNT] ____cacheline_aligned; 1172 unsigned int uclamp_flags; 1173 #define UCLAMP_FLAG_IDLE 0x01 1174 #endif 1175 1176 struct cfs_rq cfs; 1177 struct rt_rq rt; 1178 struct dl_rq dl; 1179 #ifdef CONFIG_SCHED_CLASS_EXT 1180 struct scx_rq scx; 1181 struct sched_dl_entity ext_server; 1182 #endif 1183 1184 struct sched_dl_entity fair_server; 1185 1186 #ifdef CONFIG_FAIR_GROUP_SCHED 1187 /* list of leaf cfs_rq on this CPU: */ 1188 struct list_head leaf_cfs_rq_list; 1189 struct list_head *tmp_alone_branch; 1190 #endif /* CONFIG_FAIR_GROUP_SCHED */ 1191 1192 #ifdef CONFIG_NUMA_BALANCING 1193 unsigned int numa_migrate_on; 1194 #endif 1195 /* 1196 * This is part of a global counter where only the total sum 1197 * over all CPUs matters. A task can increase this counter on 1198 * one CPU and if it got migrated afterwards it may decrease 1199 * it on another CPU. Always updated under the runqueue lock: 1200 */ 1201 unsigned long nr_uninterruptible; 1202 1203 struct sched_dl_entity *dl_server; 1204 struct task_struct *stop; 1205 const struct sched_class *next_class; 1206 unsigned long next_balance; 1207 struct mm_struct *prev_mm; 1208 1209 /* 1210 * The following fields of clock data are frequently referenced 1211 * and updated together, and should go on their own cache line. 1212 */ 1213 u64 clock_task ____cacheline_aligned; 1214 u64 clock_pelt; 1215 u64 clock; 1216 unsigned long lost_idle_time; 1217 unsigned int clock_update_flags; 1218 u64 clock_pelt_idle; 1219 u64 clock_idle; 1220 1221 #ifndef CONFIG_64BIT 1222 u64 clock_pelt_idle_copy; 1223 u64 clock_idle_copy; 1224 #endif 1225 1226 u64 last_seen_need_resched_ns; 1227 int ticks_without_resched; 1228 1229 #ifdef CONFIG_MEMBARRIER 1230 int membarrier_state; 1231 #endif 1232 1233 struct root_domain *rd; 1234 struct sched_domain __rcu *sd; 1235 1236 struct balance_callback *balance_callback; 1237 1238 unsigned char nohz_idle_balance; 1239 unsigned char idle_balance; 1240 1241 unsigned long misfit_task_load; 1242 1243 /* For active balancing */ 1244 int active_balance; 1245 int push_cpu; 1246 struct cpu_stop_work active_balance_work; 1247 1248 /* CPU of this runqueue: */ 1249 int cpu; 1250 int online; 1251 1252 struct list_head cfs_tasks; 1253 1254 struct sched_avg avg_rt; 1255 struct sched_avg avg_dl; 1256 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 1257 struct sched_avg avg_irq; 1258 #endif 1259 #ifdef CONFIG_SCHED_HW_PRESSURE 1260 struct sched_avg avg_hw; 1261 #endif 1262 u64 idle_stamp; 1263 u64 avg_idle; 1264 1265 /* This is used to determine avg_idle's max value */ 1266 u64 max_idle_balance_cost; 1267 1268 #ifdef CONFIG_HOTPLUG_CPU 1269 struct rcuwait hotplug_wait; 1270 #endif 1271 1272 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 1273 u64 prev_irq_time; 1274 u64 psi_irq_time; 1275 #endif 1276 #ifdef CONFIG_PARAVIRT 1277 u64 prev_steal_time; 1278 #endif 1279 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING 1280 u64 prev_steal_time_rq; 1281 #endif 1282 1283 /* calc_load related fields */ 1284 unsigned long calc_load_update; 1285 long calc_load_active; 1286 1287 #ifdef CONFIG_SCHED_HRTICK 1288 call_single_data_t hrtick_csd; 1289 struct hrtimer hrtick_timer; 1290 ktime_t hrtick_time; 1291 #endif 1292 1293 #ifdef CONFIG_SCHEDSTATS 1294 /* latency stats */ 1295 struct sched_info rq_sched_info; 1296 unsigned long long rq_cpu_time; 1297 1298 /* sys_sched_yield() stats */ 1299 unsigned int yld_count; 1300 1301 /* schedule() stats */ 1302 unsigned int sched_count; 1303 unsigned int sched_goidle; 1304 1305 /* try_to_wake_up() stats */ 1306 unsigned int ttwu_count; 1307 unsigned int ttwu_local; 1308 #endif 1309 1310 #ifdef CONFIG_CPU_IDLE 1311 /* Must be inspected within a RCU lock section */ 1312 struct cpuidle_state *idle_state; 1313 #endif 1314 1315 unsigned int nr_pinned; 1316 unsigned int push_busy; 1317 struct cpu_stop_work push_work; 1318 1319 #ifdef CONFIG_SCHED_CORE 1320 /* per rq */ 1321 struct rq *core; 1322 struct task_struct *core_pick; 1323 struct sched_dl_entity *core_dl_server; 1324 unsigned int core_enabled; 1325 unsigned int core_sched_seq; 1326 struct rb_root core_tree; 1327 1328 /* shared state -- careful with sched_core_cpu_deactivate() */ 1329 unsigned int core_task_seq; 1330 unsigned int core_pick_seq; 1331 unsigned long core_cookie; 1332 unsigned int core_forceidle_count; 1333 unsigned int core_forceidle_seq; 1334 unsigned int core_forceidle_occupation; 1335 u64 core_forceidle_start; 1336 #endif /* CONFIG_SCHED_CORE */ 1337 1338 /* Scratch cpumask to be temporarily used under rq_lock */ 1339 cpumask_var_t scratch_mask; 1340 1341 #ifdef CONFIG_CFS_BANDWIDTH 1342 call_single_data_t cfsb_csd; 1343 struct list_head cfsb_csd_list; 1344 #endif 1345 1346 atomic_t nr_iowait; 1347 } __no_randomize_layout; 1348 1349 #ifdef CONFIG_FAIR_GROUP_SCHED 1350 1351 /* CPU runqueue to which this cfs_rq is attached */ 1352 static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1353 { 1354 return cfs_rq->rq; 1355 } 1356 1357 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 1358 1359 static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1360 { 1361 return container_of(cfs_rq, struct rq, cfs); 1362 } 1363 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 1364 1365 static inline int cpu_of(struct rq *rq) 1366 { 1367 return rq->cpu; 1368 } 1369 1370 #define MDF_PUSH 0x01 1371 1372 static inline bool is_migration_disabled(struct task_struct *p) 1373 { 1374 return p->migration_disabled; 1375 } 1376 1377 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); 1378 DECLARE_PER_CPU(struct rnd_state, sched_rnd_state); 1379 1380 static inline u32 sched_rng(void) 1381 { 1382 return prandom_u32_state(this_cpu_ptr(&sched_rnd_state)); 1383 } 1384 1385 static __always_inline struct rq *__this_rq(void) 1386 { 1387 return this_cpu_ptr(&runqueues); 1388 } 1389 1390 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) 1391 #define this_rq() __this_rq() 1392 #define task_rq(p) cpu_rq(task_cpu(p)) 1393 #define cpu_curr(cpu) (cpu_rq(cpu)->curr) 1394 #define raw_rq() raw_cpu_ptr(&runqueues) 1395 1396 static inline bool idle_rq(struct rq *rq) 1397 { 1398 return rq->curr == rq->idle && !rq->nr_running && !rq->ttwu_pending; 1399 } 1400 1401 /** 1402 * available_idle_cpu - is a given CPU idle for enqueuing work. 1403 * @cpu: the CPU in question. 1404 * 1405 * Return: 1 if the CPU is currently idle. 0 otherwise. 1406 */ 1407 static inline bool available_idle_cpu(int cpu) 1408 { 1409 if (!idle_rq(cpu_rq(cpu))) 1410 return 0; 1411 1412 if (vcpu_is_preempted(cpu)) 1413 return 0; 1414 1415 return 1; 1416 } 1417 1418 #ifdef CONFIG_SCHED_PROXY_EXEC 1419 static inline void rq_set_donor(struct rq *rq, struct task_struct *t) 1420 { 1421 rcu_assign_pointer(rq->donor, t); 1422 } 1423 #else 1424 static inline void rq_set_donor(struct rq *rq, struct task_struct *t) 1425 { 1426 /* Do nothing */ 1427 } 1428 #endif 1429 1430 #ifdef CONFIG_SCHED_CORE 1431 static inline struct cpumask *sched_group_span(struct sched_group *sg); 1432 1433 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled); 1434 1435 static inline bool sched_core_enabled(struct rq *rq) 1436 { 1437 return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled; 1438 } 1439 1440 static inline bool sched_core_disabled(void) 1441 { 1442 return !static_branch_unlikely(&__sched_core_enabled); 1443 } 1444 1445 /* 1446 * Be careful with this function; not for general use. The return value isn't 1447 * stable unless you actually hold a relevant rq->__lock. 1448 */ 1449 static inline raw_spinlock_t *rq_lockp(struct rq *rq) 1450 { 1451 if (sched_core_enabled(rq)) 1452 return &rq->core->__lock; 1453 1454 return &rq->__lock; 1455 } 1456 1457 static inline raw_spinlock_t *__rq_lockp(struct rq *rq) 1458 __returns_ctx_lock(rq_lockp(rq)) /* alias them */ 1459 { 1460 if (rq->core_enabled) 1461 return &rq->core->__lock; 1462 1463 return &rq->__lock; 1464 } 1465 1466 extern bool 1467 cfs_prio_less(const struct task_struct *a, const struct task_struct *b, bool fi); 1468 1469 extern void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi); 1470 1471 /* 1472 * Helpers to check if the CPU's core cookie matches with the task's cookie 1473 * when core scheduling is enabled. 1474 * A special case is that the task's cookie always matches with CPU's core 1475 * cookie if the CPU is in an idle core. 1476 */ 1477 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p) 1478 { 1479 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1480 if (!sched_core_enabled(rq)) 1481 return true; 1482 1483 return rq->core->core_cookie == p->core_cookie; 1484 } 1485 1486 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) 1487 { 1488 bool idle_core = true; 1489 int cpu; 1490 1491 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1492 if (!sched_core_enabled(rq)) 1493 return true; 1494 1495 if (rq->core->core_cookie == p->core_cookie) 1496 return true; 1497 1498 for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) { 1499 if (!available_idle_cpu(cpu)) { 1500 idle_core = false; 1501 break; 1502 } 1503 } 1504 1505 /* 1506 * A CPU in an idle core is always the best choice for tasks with 1507 * cookies. 1508 */ 1509 return idle_core; 1510 } 1511 1512 static inline bool sched_group_cookie_match(struct rq *rq, 1513 struct task_struct *p, 1514 struct sched_group *group) 1515 { 1516 int cpu; 1517 1518 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1519 if (!sched_core_enabled(rq)) 1520 return true; 1521 1522 for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) { 1523 if (sched_core_cookie_match(cpu_rq(cpu), p)) 1524 return true; 1525 } 1526 return false; 1527 } 1528 1529 static inline bool sched_core_enqueued(struct task_struct *p) 1530 { 1531 return !RB_EMPTY_NODE(&p->core_node); 1532 } 1533 1534 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p); 1535 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags); 1536 1537 extern void sched_core_get(void); 1538 extern void sched_core_put(void); 1539 1540 #else /* !CONFIG_SCHED_CORE: */ 1541 1542 static inline bool sched_core_enabled(struct rq *rq) 1543 { 1544 return false; 1545 } 1546 1547 static inline bool sched_core_disabled(void) 1548 { 1549 return true; 1550 } 1551 1552 static inline raw_spinlock_t *rq_lockp(struct rq *rq) 1553 { 1554 return &rq->__lock; 1555 } 1556 1557 static inline raw_spinlock_t *__rq_lockp(struct rq *rq) 1558 __returns_ctx_lock(rq_lockp(rq)) /* alias them */ 1559 { 1560 return &rq->__lock; 1561 } 1562 1563 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p) 1564 { 1565 return true; 1566 } 1567 1568 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) 1569 { 1570 return true; 1571 } 1572 1573 static inline bool sched_group_cookie_match(struct rq *rq, 1574 struct task_struct *p, 1575 struct sched_group *group) 1576 { 1577 return true; 1578 } 1579 1580 #endif /* !CONFIG_SCHED_CORE */ 1581 1582 #ifdef CONFIG_RT_GROUP_SCHED 1583 # ifdef CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED 1584 DECLARE_STATIC_KEY_FALSE(rt_group_sched); 1585 static inline bool rt_group_sched_enabled(void) 1586 { 1587 return static_branch_unlikely(&rt_group_sched); 1588 } 1589 # else /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED: */ 1590 DECLARE_STATIC_KEY_TRUE(rt_group_sched); 1591 static inline bool rt_group_sched_enabled(void) 1592 { 1593 return static_branch_likely(&rt_group_sched); 1594 } 1595 # endif /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED */ 1596 #else /* !CONFIG_RT_GROUP_SCHED: */ 1597 # define rt_group_sched_enabled() false 1598 #endif /* !CONFIG_RT_GROUP_SCHED */ 1599 1600 static inline void lockdep_assert_rq_held(struct rq *rq) 1601 __assumes_ctx_lock(__rq_lockp(rq)) 1602 { 1603 lockdep_assert_held(__rq_lockp(rq)); 1604 } 1605 1606 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass) 1607 __acquires(__rq_lockp(rq)); 1608 1609 extern bool raw_spin_rq_trylock(struct rq *rq) 1610 __cond_acquires(true, __rq_lockp(rq)); 1611 1612 extern void raw_spin_rq_unlock(struct rq *rq) 1613 __releases(__rq_lockp(rq)); 1614 1615 static inline void raw_spin_rq_lock(struct rq *rq) 1616 __acquires(__rq_lockp(rq)) 1617 { 1618 raw_spin_rq_lock_nested(rq, 0); 1619 } 1620 1621 static inline void raw_spin_rq_lock_irq(struct rq *rq) 1622 __acquires(__rq_lockp(rq)) 1623 { 1624 local_irq_disable(); 1625 raw_spin_rq_lock(rq); 1626 } 1627 1628 static inline void raw_spin_rq_unlock_irq(struct rq *rq) 1629 __releases(__rq_lockp(rq)) 1630 { 1631 raw_spin_rq_unlock(rq); 1632 local_irq_enable(); 1633 } 1634 1635 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq) 1636 __acquires(__rq_lockp(rq)) 1637 { 1638 unsigned long flags; 1639 1640 local_irq_save(flags); 1641 raw_spin_rq_lock(rq); 1642 1643 return flags; 1644 } 1645 1646 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags) 1647 __releases(__rq_lockp(rq)) 1648 { 1649 raw_spin_rq_unlock(rq); 1650 local_irq_restore(flags); 1651 } 1652 1653 #define raw_spin_rq_lock_irqsave(rq, flags) \ 1654 do { \ 1655 flags = _raw_spin_rq_lock_irqsave(rq); \ 1656 } while (0) 1657 1658 #ifdef CONFIG_SCHED_SMT 1659 extern void __update_idle_core(struct rq *rq); 1660 1661 static inline void update_idle_core(struct rq *rq) 1662 { 1663 if (static_branch_unlikely(&sched_smt_present)) 1664 __update_idle_core(rq); 1665 } 1666 1667 #else /* !CONFIG_SCHED_SMT: */ 1668 static inline void update_idle_core(struct rq *rq) { } 1669 #endif /* !CONFIG_SCHED_SMT */ 1670 1671 #ifdef CONFIG_FAIR_GROUP_SCHED 1672 1673 static inline struct task_struct *task_of(struct sched_entity *se) 1674 { 1675 WARN_ON_ONCE(!entity_is_task(se)); 1676 return container_of(se, struct task_struct, se); 1677 } 1678 1679 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p) 1680 { 1681 return p->se.cfs_rq; 1682 } 1683 1684 /* runqueue on which this entity is (to be) queued */ 1685 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se) 1686 { 1687 return se->cfs_rq; 1688 } 1689 1690 /* runqueue "owned" by this group */ 1691 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) 1692 { 1693 return grp->my_q; 1694 } 1695 1696 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 1697 1698 #define task_of(_se) container_of(_se, struct task_struct, se) 1699 1700 static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p) 1701 { 1702 return &task_rq(p)->cfs; 1703 } 1704 1705 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se) 1706 { 1707 const struct task_struct *p = task_of(se); 1708 struct rq *rq = task_rq(p); 1709 1710 return &rq->cfs; 1711 } 1712 1713 /* runqueue "owned" by this group */ 1714 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) 1715 { 1716 return NULL; 1717 } 1718 1719 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 1720 1721 extern void update_rq_avg_idle(struct rq *rq); 1722 extern void update_rq_clock(struct rq *rq); 1723 1724 /* 1725 * rq::clock_update_flags bits 1726 * 1727 * %RQCF_REQ_SKIP - will request skipping of clock update on the next 1728 * call to __schedule(). This is an optimisation to avoid 1729 * neighbouring rq clock updates. 1730 * 1731 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is 1732 * in effect and calls to update_rq_clock() are being ignored. 1733 * 1734 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been 1735 * made to update_rq_clock() since the last time rq::lock was pinned. 1736 * 1737 * If inside of __schedule(), clock_update_flags will have been 1738 * shifted left (a left shift is a cheap operation for the fast path 1739 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use, 1740 * 1741 * if (rq-clock_update_flags >= RQCF_UPDATED) 1742 * 1743 * to check if %RQCF_UPDATED is set. It'll never be shifted more than 1744 * one position though, because the next rq_unpin_lock() will shift it 1745 * back. 1746 */ 1747 #define RQCF_REQ_SKIP 0x01 1748 #define RQCF_ACT_SKIP 0x02 1749 #define RQCF_UPDATED 0x04 1750 1751 static inline void assert_clock_updated(struct rq *rq) 1752 { 1753 /* 1754 * The only reason for not seeing a clock update since the 1755 * last rq_pin_lock() is if we're currently skipping updates. 1756 */ 1757 WARN_ON_ONCE(rq->clock_update_flags < RQCF_ACT_SKIP); 1758 } 1759 1760 static inline u64 rq_clock(struct rq *rq) 1761 { 1762 lockdep_assert_rq_held(rq); 1763 assert_clock_updated(rq); 1764 1765 return rq->clock; 1766 } 1767 1768 static inline u64 rq_clock_task(struct rq *rq) 1769 { 1770 lockdep_assert_rq_held(rq); 1771 assert_clock_updated(rq); 1772 1773 return rq->clock_task; 1774 } 1775 1776 static inline void rq_clock_skip_update(struct rq *rq) 1777 { 1778 lockdep_assert_rq_held(rq); 1779 rq->clock_update_flags |= RQCF_REQ_SKIP; 1780 } 1781 1782 /* 1783 * See rt task throttling, which is the only time a skip 1784 * request is canceled. 1785 */ 1786 static inline void rq_clock_cancel_skipupdate(struct rq *rq) 1787 { 1788 lockdep_assert_rq_held(rq); 1789 rq->clock_update_flags &= ~RQCF_REQ_SKIP; 1790 } 1791 1792 /* 1793 * During cpu offlining and rq wide unthrottling, we can trigger 1794 * an update_rq_clock() for several cfs and rt runqueues (Typically 1795 * when using list_for_each_entry_*) 1796 * rq_clock_start_loop_update() can be called after updating the clock 1797 * once and before iterating over the list to prevent multiple update. 1798 * After the iterative traversal, we need to call rq_clock_stop_loop_update() 1799 * to clear RQCF_ACT_SKIP of rq->clock_update_flags. 1800 */ 1801 static inline void rq_clock_start_loop_update(struct rq *rq) 1802 { 1803 lockdep_assert_rq_held(rq); 1804 WARN_ON_ONCE(rq->clock_update_flags & RQCF_ACT_SKIP); 1805 rq->clock_update_flags |= RQCF_ACT_SKIP; 1806 } 1807 1808 static inline void rq_clock_stop_loop_update(struct rq *rq) 1809 { 1810 lockdep_assert_rq_held(rq); 1811 rq->clock_update_flags &= ~RQCF_ACT_SKIP; 1812 } 1813 1814 struct rq_flags { 1815 unsigned long flags; 1816 struct pin_cookie cookie; 1817 /* 1818 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the 1819 * current pin context is stashed here in case it needs to be 1820 * restored in rq_repin_lock(). 1821 */ 1822 unsigned int clock_update_flags; 1823 }; 1824 1825 extern struct balance_callback balance_push_callback; 1826 1827 #ifdef CONFIG_SCHED_CLASS_EXT 1828 extern const struct sched_class ext_sched_class; 1829 1830 DECLARE_STATIC_KEY_FALSE(__scx_enabled); /* SCX BPF scheduler loaded */ 1831 DECLARE_STATIC_KEY_FALSE(__scx_switched_all); /* all fair class tasks on SCX */ 1832 1833 #define scx_enabled() static_branch_unlikely(&__scx_enabled) 1834 #define scx_switched_all() static_branch_unlikely(&__scx_switched_all) 1835 1836 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) 1837 { 1838 if (!scx_enabled()) 1839 return; 1840 WRITE_ONCE(rq->scx.clock, clock); 1841 smp_store_release(&rq->scx.flags, rq->scx.flags | SCX_RQ_CLK_VALID); 1842 } 1843 1844 static inline void scx_rq_clock_invalidate(struct rq *rq) 1845 { 1846 if (!scx_enabled()) 1847 return; 1848 WRITE_ONCE(rq->scx.flags, rq->scx.flags & ~SCX_RQ_CLK_VALID); 1849 } 1850 1851 #else /* !CONFIG_SCHED_CLASS_EXT: */ 1852 #define scx_enabled() false 1853 #define scx_switched_all() false 1854 1855 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) {} 1856 static inline void scx_rq_clock_invalidate(struct rq *rq) {} 1857 #endif /* !CONFIG_SCHED_CLASS_EXT */ 1858 1859 /* 1860 * Lockdep annotation that avoids accidental unlocks; it's like a 1861 * sticky/continuous lockdep_assert_held(). 1862 * 1863 * This avoids code that has access to 'struct rq *rq' (basically everything in 1864 * the scheduler) from accidentally unlocking the rq if they do not also have a 1865 * copy of the (on-stack) 'struct rq_flags rf'. 1866 * 1867 * Also see Documentation/locking/lockdep-design.rst. 1868 */ 1869 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf) 1870 { 1871 rf->cookie = lockdep_pin_lock(__rq_lockp(rq)); 1872 1873 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 1874 rf->clock_update_flags = 0; 1875 WARN_ON_ONCE(rq->balance_callback && rq->balance_callback != &balance_push_callback); 1876 } 1877 1878 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf) 1879 { 1880 if (rq->clock_update_flags > RQCF_ACT_SKIP) 1881 rf->clock_update_flags = RQCF_UPDATED; 1882 1883 scx_rq_clock_invalidate(rq); 1884 lockdep_unpin_lock(__rq_lockp(rq), rf->cookie); 1885 } 1886 1887 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf) 1888 { 1889 lockdep_repin_lock(__rq_lockp(rq), rf->cookie); 1890 1891 /* 1892 * Restore the value we stashed in @rf for this pin context. 1893 */ 1894 rq->clock_update_flags |= rf->clock_update_flags; 1895 } 1896 1897 #define __task_rq_lock(...) __acquire_ret(___task_rq_lock(__VA_ARGS__), __rq_lockp(__ret)) 1898 extern struct rq *___task_rq_lock(struct task_struct *p, struct rq_flags *rf) __acquires_ret; 1899 1900 #define task_rq_lock(...) __acquire_ret(_task_rq_lock(__VA_ARGS__), __rq_lockp(__ret)) 1901 extern struct rq *_task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1902 __acquires(&p->pi_lock) __acquires_ret; 1903 1904 static inline void 1905 __task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) 1906 __releases(__rq_lockp(rq)) 1907 { 1908 rq_unpin_lock(rq, rf); 1909 raw_spin_rq_unlock(rq); 1910 } 1911 1912 static inline void 1913 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) 1914 __releases(__rq_lockp(rq), &p->pi_lock) 1915 { 1916 __task_rq_unlock(rq, p, rf); 1917 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); 1918 } 1919 1920 DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct, 1921 _T->rq = task_rq_lock(_T->lock, &_T->rf), 1922 task_rq_unlock(_T->rq, _T->lock, &_T->rf), 1923 struct rq *rq; struct rq_flags rf) 1924 DECLARE_LOCK_GUARD_1_ATTRS(task_rq_lock, __acquires(_T->pi_lock), __releases((*(struct task_struct **)_T)->pi_lock)) 1925 #define class_task_rq_lock_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(task_rq_lock, _T) 1926 1927 DEFINE_LOCK_GUARD_1(__task_rq_lock, struct task_struct, 1928 _T->rq = __task_rq_lock(_T->lock, &_T->rf), 1929 __task_rq_unlock(_T->rq, _T->lock, &_T->rf), 1930 struct rq *rq; struct rq_flags rf) 1931 1932 static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) 1933 __acquires(__rq_lockp(rq)) 1934 { 1935 raw_spin_rq_lock_irqsave(rq, rf->flags); 1936 rq_pin_lock(rq, rf); 1937 } 1938 1939 static inline void rq_lock_irq(struct rq *rq, struct rq_flags *rf) 1940 __acquires(__rq_lockp(rq)) 1941 { 1942 raw_spin_rq_lock_irq(rq); 1943 rq_pin_lock(rq, rf); 1944 } 1945 1946 static inline void rq_lock(struct rq *rq, struct rq_flags *rf) 1947 __acquires(__rq_lockp(rq)) 1948 { 1949 raw_spin_rq_lock(rq); 1950 rq_pin_lock(rq, rf); 1951 } 1952 1953 static inline void rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf) 1954 __releases(__rq_lockp(rq)) 1955 { 1956 rq_unpin_lock(rq, rf); 1957 raw_spin_rq_unlock_irqrestore(rq, rf->flags); 1958 } 1959 1960 static inline void rq_unlock_irq(struct rq *rq, struct rq_flags *rf) 1961 __releases(__rq_lockp(rq)) 1962 { 1963 rq_unpin_lock(rq, rf); 1964 raw_spin_rq_unlock_irq(rq); 1965 } 1966 1967 static inline void rq_unlock(struct rq *rq, struct rq_flags *rf) 1968 __releases(__rq_lockp(rq)) 1969 { 1970 rq_unpin_lock(rq, rf); 1971 raw_spin_rq_unlock(rq); 1972 } 1973 1974 DEFINE_LOCK_GUARD_1(rq_lock, struct rq, 1975 rq_lock(_T->lock, &_T->rf), 1976 rq_unlock(_T->lock, &_T->rf), 1977 struct rq_flags rf) 1978 1979 DECLARE_LOCK_GUARD_1_ATTRS(rq_lock, __acquires(__rq_lockp(_T)), __releases(__rq_lockp(*(struct rq **)_T))); 1980 #define class_rq_lock_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock, _T) 1981 1982 DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq, 1983 rq_lock_irq(_T->lock, &_T->rf), 1984 rq_unlock_irq(_T->lock, &_T->rf), 1985 struct rq_flags rf) 1986 1987 DECLARE_LOCK_GUARD_1_ATTRS(rq_lock_irq, __acquires(__rq_lockp(_T)), __releases(__rq_lockp(*(struct rq **)_T))); 1988 #define class_rq_lock_irq_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock_irq, _T) 1989 1990 DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq, 1991 rq_lock_irqsave(_T->lock, &_T->rf), 1992 rq_unlock_irqrestore(_T->lock, &_T->rf), 1993 struct rq_flags rf) 1994 1995 DECLARE_LOCK_GUARD_1_ATTRS(rq_lock_irqsave, __acquires(__rq_lockp(_T)), __releases(__rq_lockp(*(struct rq **)_T))); 1996 #define class_rq_lock_irqsave_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock_irqsave, _T) 1997 1998 #define this_rq_lock_irq(...) __acquire_ret(_this_rq_lock_irq(__VA_ARGS__), __rq_lockp(__ret)) 1999 static inline struct rq *_this_rq_lock_irq(struct rq_flags *rf) __acquires_ret 2000 { 2001 struct rq *rq; 2002 2003 local_irq_disable(); 2004 rq = this_rq(); 2005 rq_lock(rq, rf); 2006 2007 return rq; 2008 } 2009 2010 #ifdef CONFIG_NUMA 2011 2012 enum numa_topology_type { 2013 NUMA_DIRECT, 2014 NUMA_GLUELESS_MESH, 2015 NUMA_BACKPLANE, 2016 }; 2017 2018 extern enum numa_topology_type sched_numa_topology_type; 2019 extern int sched_max_numa_distance; 2020 extern bool find_numa_distance(int distance); 2021 extern void sched_init_numa(int offline_node); 2022 extern void sched_update_numa(int cpu, bool online); 2023 extern void sched_domains_numa_masks_set(unsigned int cpu); 2024 extern void sched_domains_numa_masks_clear(unsigned int cpu); 2025 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu); 2026 2027 #else /* !CONFIG_NUMA: */ 2028 2029 static inline void sched_init_numa(int offline_node) { } 2030 static inline void sched_update_numa(int cpu, bool online) { } 2031 static inline void sched_domains_numa_masks_set(unsigned int cpu) { } 2032 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { } 2033 2034 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu) 2035 { 2036 return nr_cpu_ids; 2037 } 2038 2039 #endif /* !CONFIG_NUMA */ 2040 2041 #ifdef CONFIG_NUMA_BALANCING 2042 2043 /* The regions in numa_faults array from task_struct */ 2044 enum numa_faults_stats { 2045 NUMA_MEM = 0, 2046 NUMA_CPU, 2047 NUMA_MEMBUF, 2048 NUMA_CPUBUF 2049 }; 2050 2051 extern void sched_setnuma(struct task_struct *p, int node); 2052 extern int migrate_task_to(struct task_struct *p, int cpu); 2053 extern int migrate_swap(struct task_struct *p, struct task_struct *t, 2054 int cpu, int scpu); 2055 extern void init_numa_balancing(u64 clone_flags, struct task_struct *p); 2056 2057 #else /* !CONFIG_NUMA_BALANCING: */ 2058 2059 static inline void 2060 init_numa_balancing(u64 clone_flags, struct task_struct *p) 2061 { 2062 } 2063 2064 #endif /* !CONFIG_NUMA_BALANCING */ 2065 2066 static inline void 2067 queue_balance_callback(struct rq *rq, 2068 struct balance_callback *head, 2069 void (*func)(struct rq *rq)) 2070 { 2071 lockdep_assert_rq_held(rq); 2072 2073 /* 2074 * Don't (re)queue an already queued item; nor queue anything when 2075 * balance_push() is active, see the comment with 2076 * balance_push_callback. 2077 */ 2078 if (unlikely(head->next || rq->balance_callback == &balance_push_callback)) 2079 return; 2080 2081 head->func = func; 2082 head->next = rq->balance_callback; 2083 rq->balance_callback = head; 2084 } 2085 2086 #define rcu_dereference_sched_domain(p) \ 2087 rcu_dereference_all_check((p), lockdep_is_held(&sched_domains_mutex)) 2088 2089 /* 2090 * The domain tree (rq->sd) is protected by RCU's quiescent state transition. 2091 * See destroy_sched_domains: call_rcu for details. 2092 * 2093 * The domain tree of any CPU may only be accessed from within 2094 * preempt-disabled sections. 2095 */ 2096 #define for_each_domain(cpu, __sd) \ 2097 for (__sd = rcu_dereference_sched_domain(cpu_rq(cpu)->sd); \ 2098 __sd; __sd = __sd->parent) 2099 2100 /* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */ 2101 #define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) | 2102 static const unsigned int SD_SHARED_CHILD_MASK = 2103 #include <linux/sched/sd_flags.h> 2104 0; 2105 #undef SD_FLAG 2106 2107 /** 2108 * highest_flag_domain - Return highest sched_domain containing flag. 2109 * @cpu: The CPU whose highest level of sched domain is to 2110 * be returned. 2111 * @flag: The flag to check for the highest sched_domain 2112 * for the given CPU. 2113 * 2114 * Returns the highest sched_domain of a CPU which contains @flag. If @flag has 2115 * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag. 2116 */ 2117 static inline struct sched_domain *highest_flag_domain(int cpu, int flag) 2118 { 2119 struct sched_domain *sd, *hsd = NULL; 2120 2121 for_each_domain(cpu, sd) { 2122 if (sd->flags & flag) { 2123 hsd = sd; 2124 continue; 2125 } 2126 2127 /* 2128 * Stop the search if @flag is known to be shared at lower 2129 * levels. It will not be found further up. 2130 */ 2131 if (flag & SD_SHARED_CHILD_MASK) 2132 break; 2133 } 2134 2135 return hsd; 2136 } 2137 2138 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) 2139 { 2140 struct sched_domain *sd; 2141 2142 for_each_domain(cpu, sd) { 2143 if (sd->flags & flag) 2144 break; 2145 } 2146 2147 return sd; 2148 } 2149 2150 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc); 2151 DECLARE_PER_CPU(int, sd_llc_size); 2152 DECLARE_PER_CPU(int, sd_llc_id); 2153 DECLARE_PER_CPU(int, sd_share_id); 2154 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared); 2155 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa); 2156 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing); 2157 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity); 2158 2159 extern struct static_key_false sched_asym_cpucapacity; 2160 extern struct static_key_false sched_cluster_active; 2161 2162 static __always_inline bool sched_asym_cpucap_active(void) 2163 { 2164 return static_branch_unlikely(&sched_asym_cpucapacity); 2165 } 2166 2167 struct sched_group_capacity { 2168 atomic_t ref; 2169 /* 2170 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity 2171 * for a single CPU. 2172 */ 2173 unsigned long capacity; 2174 unsigned long min_capacity; /* Min per-CPU capacity in group */ 2175 unsigned long max_capacity; /* Max per-CPU capacity in group */ 2176 unsigned long next_update; 2177 int imbalance; /* XXX unrelated to capacity but shared group state */ 2178 2179 int id; 2180 2181 unsigned long cpumask[]; /* Balance mask */ 2182 }; 2183 2184 struct sched_group { 2185 struct sched_group *next; /* Must be a circular list */ 2186 atomic_t ref; 2187 2188 unsigned int group_weight; 2189 unsigned int cores; 2190 struct sched_group_capacity *sgc; 2191 int asym_prefer_cpu; /* CPU of highest priority in group */ 2192 int flags; 2193 2194 /* 2195 * The CPUs this group covers. 2196 * 2197 * NOTE: this field is variable length. (Allocated dynamically 2198 * by attaching extra space to the end of the structure, 2199 * depending on how many CPUs the kernel has booted up with) 2200 */ 2201 unsigned long cpumask[]; 2202 }; 2203 2204 static inline struct cpumask *sched_group_span(struct sched_group *sg) 2205 { 2206 return to_cpumask(sg->cpumask); 2207 } 2208 2209 /* 2210 * See build_balance_mask(). 2211 */ 2212 static inline struct cpumask *group_balance_mask(struct sched_group *sg) 2213 { 2214 return to_cpumask(sg->sgc->cpumask); 2215 } 2216 2217 extern int group_balance_cpu(struct sched_group *sg); 2218 2219 extern void update_sched_domain_debugfs(void); 2220 extern void dirty_sched_domain_sysctl(int cpu); 2221 2222 extern int sched_update_scaling(void); 2223 2224 static inline const struct cpumask *task_user_cpus(struct task_struct *p) 2225 { 2226 if (!p->user_cpus_ptr) 2227 return cpu_possible_mask; /* &init_task.cpus_mask */ 2228 return p->user_cpus_ptr; 2229 } 2230 2231 #ifdef CONFIG_CGROUP_SCHED 2232 2233 /* 2234 * Return the group to which this tasks belongs. 2235 * 2236 * We cannot use task_css() and friends because the cgroup subsystem 2237 * changes that value before the cgroup_subsys::attach() method is called, 2238 * therefore we cannot pin it and might observe the wrong value. 2239 * 2240 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup 2241 * core changes this before calling sched_move_task(). 2242 * 2243 * Instead we use a 'copy' which is updated from sched_move_task() while 2244 * holding both task_struct::pi_lock and rq::lock. 2245 */ 2246 static inline struct task_group *task_group(struct task_struct *p) 2247 { 2248 return p->sched_task_group; 2249 } 2250 2251 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ 2252 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) 2253 { 2254 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED) 2255 struct task_group *tg = task_group(p); 2256 #endif 2257 2258 #ifdef CONFIG_FAIR_GROUP_SCHED 2259 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]); 2260 p->se.cfs_rq = tg->cfs_rq[cpu]; 2261 p->se.parent = tg->se[cpu]; 2262 p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0; 2263 #endif 2264 2265 #ifdef CONFIG_RT_GROUP_SCHED 2266 /* 2267 * p->rt.rt_rq is NULL initially and it is easier to assign 2268 * root_task_group's rt_rq than switching in rt_rq_of_se() 2269 * Clobbers tg(!) 2270 */ 2271 if (!rt_group_sched_enabled()) 2272 tg = &root_task_group; 2273 p->rt.rt_rq = tg->rt_rq[cpu]; 2274 p->rt.parent = tg->rt_se[cpu]; 2275 #endif /* CONFIG_RT_GROUP_SCHED */ 2276 } 2277 2278 #else /* !CONFIG_CGROUP_SCHED: */ 2279 2280 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } 2281 2282 static inline struct task_group *task_group(struct task_struct *p) 2283 { 2284 return NULL; 2285 } 2286 2287 #endif /* !CONFIG_CGROUP_SCHED */ 2288 2289 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) 2290 { 2291 set_task_rq(p, cpu); 2292 #ifdef CONFIG_SMP 2293 /* 2294 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be 2295 * successfully executed on another CPU. We must ensure that updates of 2296 * per-task data have been completed by this moment. 2297 */ 2298 smp_wmb(); 2299 WRITE_ONCE(task_thread_info(p)->cpu, cpu); 2300 p->wake_cpu = cpu; 2301 rseq_sched_set_ids_changed(p); 2302 #endif /* CONFIG_SMP */ 2303 } 2304 2305 /* 2306 * Tunables: 2307 */ 2308 2309 #define SCHED_FEAT(name, enabled) \ 2310 __SCHED_FEAT_##name , 2311 2312 enum { 2313 #include "features.h" 2314 __SCHED_FEAT_NR, 2315 }; 2316 2317 #undef SCHED_FEAT 2318 2319 /* 2320 * To support run-time toggling of sched features, all the translation units 2321 * (but core.c) reference the sysctl_sched_features defined in core.c. 2322 */ 2323 extern __read_mostly unsigned int sysctl_sched_features; 2324 2325 #ifdef CONFIG_JUMP_LABEL 2326 2327 #define SCHED_FEAT(name, enabled) \ 2328 static __always_inline bool static_branch_##name(struct static_key *key) \ 2329 { \ 2330 return static_key_##enabled(key); \ 2331 } 2332 2333 #include "features.h" 2334 #undef SCHED_FEAT 2335 2336 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR]; 2337 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x])) 2338 2339 #else /* !CONFIG_JUMP_LABEL: */ 2340 2341 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) 2342 2343 #endif /* !CONFIG_JUMP_LABEL */ 2344 2345 extern struct static_key_false sched_numa_balancing; 2346 extern struct static_key_false sched_schedstats; 2347 2348 static inline u64 global_rt_period(void) 2349 { 2350 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC; 2351 } 2352 2353 static inline u64 global_rt_runtime(void) 2354 { 2355 if (sysctl_sched_rt_runtime < 0) 2356 return RUNTIME_INF; 2357 2358 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC; 2359 } 2360 2361 /* 2362 * Is p the current execution context? 2363 */ 2364 static inline int task_current(struct rq *rq, struct task_struct *p) 2365 { 2366 return rq->curr == p; 2367 } 2368 2369 /* 2370 * Is p the current scheduling context? 2371 * 2372 * Note that it might be the current execution context at the same time if 2373 * rq->curr == rq->donor == p. 2374 */ 2375 static inline int task_current_donor(struct rq *rq, struct task_struct *p) 2376 { 2377 return rq->donor == p; 2378 } 2379 2380 static inline bool task_is_blocked(struct task_struct *p) 2381 { 2382 if (!sched_proxy_exec()) 2383 return false; 2384 2385 return !!p->blocked_on; 2386 } 2387 2388 static inline int task_on_cpu(struct rq *rq, struct task_struct *p) 2389 { 2390 return p->on_cpu; 2391 } 2392 2393 static inline int task_on_rq_queued(struct task_struct *p) 2394 { 2395 return READ_ONCE(p->on_rq) == TASK_ON_RQ_QUEUED; 2396 } 2397 2398 static inline int task_on_rq_migrating(struct task_struct *p) 2399 { 2400 return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING; 2401 } 2402 2403 /* Wake flags. The first three directly map to some SD flag value */ 2404 #define WF_EXEC 0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */ 2405 #define WF_FORK 0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */ 2406 #define WF_TTWU 0x08 /* Wakeup; maps to SD_BALANCE_WAKE */ 2407 2408 #define WF_SYNC 0x10 /* Waker goes to sleep after wakeup */ 2409 #define WF_MIGRATED 0x20 /* Internal use, task got migrated */ 2410 #define WF_CURRENT_CPU 0x40 /* Prefer to move the wakee to the current CPU. */ 2411 #define WF_RQ_SELECTED 0x80 /* ->select_task_rq() was called */ 2412 2413 static_assert(WF_EXEC == SD_BALANCE_EXEC); 2414 static_assert(WF_FORK == SD_BALANCE_FORK); 2415 static_assert(WF_TTWU == SD_BALANCE_WAKE); 2416 2417 /* 2418 * To aid in avoiding the subversion of "niceness" due to uneven distribution 2419 * of tasks with abnormal "nice" values across CPUs the contribution that 2420 * each task makes to its run queue's load is weighted according to its 2421 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a 2422 * scaled version of the new time slice allocation that they receive on time 2423 * slice expiry etc. 2424 */ 2425 2426 #define WEIGHT_IDLEPRIO 3 2427 #define WMULT_IDLEPRIO 1431655765 2428 2429 extern const int sched_prio_to_weight[40]; 2430 extern const u32 sched_prio_to_wmult[40]; 2431 2432 /* 2433 * {de,en}queue flags: 2434 * 2435 * SLEEP/WAKEUP - task is no-longer/just-became runnable 2436 * 2437 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks 2438 * are in a known state which allows modification. Such pairs 2439 * should preserve as much state as possible. 2440 * 2441 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location 2442 * in the runqueue. IOW the priority is allowed to change. Callers 2443 * must expect to deal with balance callbacks. 2444 * 2445 * NOCLOCK - skip the update_rq_clock() (avoids double updates) 2446 * 2447 * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE) 2448 * 2449 * DELAYED - de/re-queue a sched_delayed task 2450 * 2451 * CLASS - going to update p->sched_class; makes sched_change call the 2452 * various switch methods. 2453 * 2454 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified) 2455 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline) 2456 * ENQUEUE_MIGRATED - the task was migrated during wakeup 2457 * ENQUEUE_RQ_SELECTED - ->select_task_rq() was called 2458 * 2459 * XXX SAVE/RESTORE in combination with CLASS doesn't really make sense, but 2460 * SCHED_DEADLINE seems to rely on this for now. 2461 */ 2462 2463 #define DEQUEUE_SLEEP 0x0001 /* Matches ENQUEUE_WAKEUP */ 2464 #define DEQUEUE_SAVE 0x0002 /* Matches ENQUEUE_RESTORE */ 2465 #define DEQUEUE_MOVE 0x0004 /* Matches ENQUEUE_MOVE */ 2466 #define DEQUEUE_NOCLOCK 0x0008 /* Matches ENQUEUE_NOCLOCK */ 2467 2468 #define DEQUEUE_MIGRATING 0x0010 /* Matches ENQUEUE_MIGRATING */ 2469 #define DEQUEUE_DELAYED 0x0020 /* Matches ENQUEUE_DELAYED */ 2470 #define DEQUEUE_CLASS 0x0040 /* Matches ENQUEUE_CLASS */ 2471 2472 #define DEQUEUE_SPECIAL 0x00010000 2473 #define DEQUEUE_THROTTLE 0x00020000 2474 2475 #define ENQUEUE_WAKEUP 0x0001 2476 #define ENQUEUE_RESTORE 0x0002 2477 #define ENQUEUE_MOVE 0x0004 2478 #define ENQUEUE_NOCLOCK 0x0008 2479 2480 #define ENQUEUE_MIGRATING 0x0010 2481 #define ENQUEUE_DELAYED 0x0020 2482 #define ENQUEUE_CLASS 0x0040 2483 2484 #define ENQUEUE_HEAD 0x00010000 2485 #define ENQUEUE_REPLENISH 0x00020000 2486 #define ENQUEUE_MIGRATED 0x00040000 2487 #define ENQUEUE_INITIAL 0x00080000 2488 #define ENQUEUE_RQ_SELECTED 0x00100000 2489 2490 #define RETRY_TASK ((void *)-1UL) 2491 2492 struct affinity_context { 2493 const struct cpumask *new_mask; 2494 struct cpumask *user_mask; 2495 unsigned int flags; 2496 }; 2497 2498 extern s64 update_curr_common(struct rq *rq); 2499 2500 struct sched_class { 2501 2502 #ifdef CONFIG_UCLAMP_TASK 2503 int uclamp_enabled; 2504 #endif 2505 2506 /* 2507 * move_queued_task/activate_task/enqueue_task: rq->lock 2508 * ttwu_do_activate/activate_task/enqueue_task: rq->lock 2509 * wake_up_new_task/activate_task/enqueue_task: task_rq_lock 2510 * ttwu_runnable/enqueue_task: task_rq_lock 2511 * proxy_task_current: rq->lock 2512 * sched_change_end 2513 */ 2514 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags); 2515 /* 2516 * move_queued_task/deactivate_task/dequeue_task: rq->lock 2517 * __schedule/block_task/dequeue_task: rq->lock 2518 * proxy_task_current: rq->lock 2519 * wait_task_inactive: task_rq_lock 2520 * sched_change_begin 2521 */ 2522 bool (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags); 2523 2524 /* 2525 * do_sched_yield: rq->lock 2526 */ 2527 void (*yield_task) (struct rq *rq); 2528 /* 2529 * yield_to: rq->lock (double) 2530 */ 2531 bool (*yield_to_task)(struct rq *rq, struct task_struct *p); 2532 2533 /* 2534 * move_queued_task: rq->lock 2535 * __migrate_swap_task: rq->lock 2536 * ttwu_do_activate: rq->lock 2537 * ttwu_runnable: task_rq_lock 2538 * wake_up_new_task: task_rq_lock 2539 */ 2540 void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags); 2541 2542 /* 2543 * schedule/pick_next_task/prev_balance: rq->lock 2544 */ 2545 int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf); 2546 2547 /* 2548 * schedule/pick_next_task: rq->lock 2549 */ 2550 struct task_struct *(*pick_task)(struct rq *rq, struct rq_flags *rf); 2551 /* 2552 * Optional! When implemented pick_next_task() should be equivalent to: 2553 * 2554 * next = pick_task(); 2555 * if (next) { 2556 * put_prev_task(prev); 2557 * set_next_task_first(next); 2558 * } 2559 */ 2560 struct task_struct *(*pick_next_task)(struct rq *rq, struct task_struct *prev, 2561 struct rq_flags *rf); 2562 2563 /* 2564 * sched_change: 2565 * __schedule: rq->lock 2566 */ 2567 void (*put_prev_task)(struct rq *rq, struct task_struct *p, struct task_struct *next); 2568 void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first); 2569 2570 /* 2571 * select_task_rq: p->pi_lock 2572 * sched_exec: p->pi_lock 2573 */ 2574 int (*select_task_rq)(struct task_struct *p, int task_cpu, int flags); 2575 2576 /* 2577 * set_task_cpu: p->pi_lock || rq->lock (ttwu like) 2578 */ 2579 void (*migrate_task_rq)(struct task_struct *p, int new_cpu); 2580 2581 /* 2582 * ttwu_do_activate: rq->lock 2583 * wake_up_new_task: task_rq_lock 2584 */ 2585 void (*task_woken)(struct rq *this_rq, struct task_struct *task); 2586 2587 /* 2588 * do_set_cpus_allowed: task_rq_lock + sched_change 2589 */ 2590 void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx); 2591 2592 /* 2593 * sched_set_rq_{on,off}line: rq->lock 2594 */ 2595 void (*rq_online)(struct rq *rq); 2596 void (*rq_offline)(struct rq *rq); 2597 2598 /* 2599 * push_cpu_stop: p->pi_lock && rq->lock 2600 */ 2601 struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq); 2602 2603 /* 2604 * hrtick: rq->lock 2605 * sched_tick: rq->lock 2606 * sched_tick_remote: rq->lock 2607 */ 2608 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued); 2609 /* 2610 * sched_cgroup_fork: p->pi_lock 2611 */ 2612 void (*task_fork)(struct task_struct *p); 2613 /* 2614 * finish_task_switch: no locks 2615 */ 2616 void (*task_dead)(struct task_struct *p); 2617 2618 /* 2619 * sched_change 2620 */ 2621 void (*switching_from)(struct rq *this_rq, struct task_struct *task); 2622 void (*switched_from) (struct rq *this_rq, struct task_struct *task); 2623 void (*switching_to) (struct rq *this_rq, struct task_struct *task); 2624 void (*switched_to) (struct rq *this_rq, struct task_struct *task); 2625 u64 (*get_prio) (struct rq *this_rq, struct task_struct *task); 2626 void (*prio_changed) (struct rq *this_rq, struct task_struct *task, 2627 u64 oldprio); 2628 2629 /* 2630 * set_load_weight: task_rq_lock + sched_change 2631 * __setscheduler_parms: task_rq_lock + sched_change 2632 */ 2633 void (*reweight_task)(struct rq *this_rq, struct task_struct *task, 2634 const struct load_weight *lw); 2635 2636 /* 2637 * sched_rr_get_interval: task_rq_lock 2638 */ 2639 unsigned int (*get_rr_interval)(struct rq *rq, 2640 struct task_struct *task); 2641 2642 /* 2643 * task_sched_runtime: task_rq_lock 2644 */ 2645 void (*update_curr)(struct rq *rq); 2646 2647 #ifdef CONFIG_FAIR_GROUP_SCHED 2648 /* 2649 * sched_change_group: task_rq_lock + sched_change 2650 */ 2651 void (*task_change_group)(struct task_struct *p); 2652 #endif 2653 2654 #ifdef CONFIG_SCHED_CORE 2655 /* 2656 * pick_next_task: rq->lock 2657 * try_steal_cookie: rq->lock (double) 2658 */ 2659 int (*task_is_throttled)(struct task_struct *p, int cpu); 2660 #endif 2661 }; 2662 2663 static inline void put_prev_task(struct rq *rq, struct task_struct *prev) 2664 { 2665 WARN_ON_ONCE(rq->donor != prev); 2666 prev->sched_class->put_prev_task(rq, prev, NULL); 2667 } 2668 2669 static inline void set_next_task(struct rq *rq, struct task_struct *next) 2670 { 2671 next->sched_class->set_next_task(rq, next, false); 2672 } 2673 2674 static inline void 2675 __put_prev_set_next_dl_server(struct rq *rq, 2676 struct task_struct *prev, 2677 struct task_struct *next) 2678 { 2679 prev->dl_server = NULL; 2680 next->dl_server = rq->dl_server; 2681 rq->dl_server = NULL; 2682 } 2683 2684 static inline void put_prev_set_next_task(struct rq *rq, 2685 struct task_struct *prev, 2686 struct task_struct *next) 2687 { 2688 WARN_ON_ONCE(rq->donor != prev); 2689 2690 __put_prev_set_next_dl_server(rq, prev, next); 2691 2692 if (next == prev) 2693 return; 2694 2695 prev->sched_class->put_prev_task(rq, prev, next); 2696 next->sched_class->set_next_task(rq, next, true); 2697 } 2698 2699 /* 2700 * Helper to define a sched_class instance; each one is placed in a separate 2701 * section which is ordered by the linker script: 2702 * 2703 * include/asm-generic/vmlinux.lds.h 2704 * 2705 * *CAREFUL* they are laid out in *REVERSE* order!!! 2706 * 2707 * Also enforce alignment on the instance, not the type, to guarantee layout. 2708 */ 2709 #define DEFINE_SCHED_CLASS(name) \ 2710 const struct sched_class name##_sched_class \ 2711 __aligned(__alignof__(struct sched_class)) \ 2712 __section("__" #name "_sched_class") 2713 2714 /* Defined in include/asm-generic/vmlinux.lds.h */ 2715 extern struct sched_class __sched_class_highest[]; 2716 extern struct sched_class __sched_class_lowest[]; 2717 2718 extern const struct sched_class stop_sched_class; 2719 extern const struct sched_class dl_sched_class; 2720 extern const struct sched_class rt_sched_class; 2721 extern const struct sched_class fair_sched_class; 2722 extern const struct sched_class idle_sched_class; 2723 2724 /* 2725 * Iterate only active classes. SCX can take over all fair tasks or be 2726 * completely disabled. If the former, skip fair. If the latter, skip SCX. 2727 */ 2728 static inline const struct sched_class *next_active_class(const struct sched_class *class) 2729 { 2730 class++; 2731 #ifdef CONFIG_SCHED_CLASS_EXT 2732 if (scx_switched_all() && class == &fair_sched_class) 2733 class++; 2734 if (!scx_enabled() && class == &ext_sched_class) 2735 class++; 2736 #endif 2737 return class; 2738 } 2739 2740 #define for_class_range(class, _from, _to) \ 2741 for (class = (_from); class < (_to); class++) 2742 2743 #define for_each_class(class) \ 2744 for_class_range(class, __sched_class_highest, __sched_class_lowest) 2745 2746 #define for_active_class_range(class, _from, _to) \ 2747 for (class = (_from); class != (_to); class = next_active_class(class)) 2748 2749 #define for_each_active_class(class) \ 2750 for_active_class_range(class, __sched_class_highest, __sched_class_lowest) 2751 2752 #define sched_class_above(_a, _b) ((_a) < (_b)) 2753 2754 static inline void rq_modified_begin(struct rq *rq, const struct sched_class *class) 2755 { 2756 if (sched_class_above(rq->next_class, class)) 2757 rq->next_class = class; 2758 } 2759 2760 static inline bool rq_modified_above(struct rq *rq, const struct sched_class *class) 2761 { 2762 return sched_class_above(rq->next_class, class); 2763 } 2764 2765 static inline bool sched_stop_runnable(struct rq *rq) 2766 { 2767 return rq->stop && task_on_rq_queued(rq->stop); 2768 } 2769 2770 static inline bool sched_dl_runnable(struct rq *rq) 2771 { 2772 return rq->dl.dl_nr_running > 0; 2773 } 2774 2775 static inline bool sched_rt_runnable(struct rq *rq) 2776 { 2777 return rq->rt.rt_queued > 0; 2778 } 2779 2780 static inline bool sched_fair_runnable(struct rq *rq) 2781 { 2782 return rq->cfs.nr_queued > 0; 2783 } 2784 2785 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, 2786 struct rq_flags *rf); 2787 extern struct task_struct *pick_task_idle(struct rq *rq, struct rq_flags *rf); 2788 2789 #define SCA_CHECK 0x01 2790 #define SCA_MIGRATE_DISABLE 0x02 2791 #define SCA_MIGRATE_ENABLE 0x04 2792 #define SCA_USER 0x08 2793 2794 extern void update_group_capacity(struct sched_domain *sd, int cpu); 2795 2796 extern void sched_balance_trigger(struct rq *rq); 2797 2798 extern int __set_cpus_allowed_ptr(struct task_struct *p, struct affinity_context *ctx); 2799 extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx); 2800 2801 static inline bool task_allowed_on_cpu(struct task_struct *p, int cpu) 2802 { 2803 /* When not in the task's cpumask, no point in looking further. */ 2804 if (!cpumask_test_cpu(cpu, p->cpus_ptr)) 2805 return false; 2806 2807 /* Can @cpu run a user thread? */ 2808 if (!(p->flags & PF_KTHREAD) && !task_cpu_possible(cpu, p)) 2809 return false; 2810 2811 return true; 2812 } 2813 2814 static inline cpumask_t *alloc_user_cpus_ptr(int node) 2815 { 2816 /* 2817 * See set_cpus_allowed_force() above for the rcu_head usage. 2818 */ 2819 int size = max_t(int, cpumask_size(), sizeof(struct rcu_head)); 2820 2821 return kmalloc_node(size, GFP_KERNEL, node); 2822 } 2823 2824 static inline struct task_struct *get_push_task(struct rq *rq) 2825 { 2826 struct task_struct *p = rq->donor; 2827 2828 lockdep_assert_rq_held(rq); 2829 2830 if (rq->push_busy) 2831 return NULL; 2832 2833 if (p->nr_cpus_allowed == 1) 2834 return NULL; 2835 2836 if (p->migration_disabled) 2837 return NULL; 2838 2839 rq->push_busy = true; 2840 return get_task_struct(p); 2841 } 2842 2843 extern int push_cpu_stop(void *arg); 2844 2845 #ifdef CONFIG_CPU_IDLE 2846 2847 static inline void idle_set_state(struct rq *rq, 2848 struct cpuidle_state *idle_state) 2849 { 2850 rq->idle_state = idle_state; 2851 } 2852 2853 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 2854 { 2855 WARN_ON_ONCE(!rcu_read_lock_held()); 2856 2857 return rq->idle_state; 2858 } 2859 2860 #else /* !CONFIG_CPU_IDLE: */ 2861 2862 static inline void idle_set_state(struct rq *rq, 2863 struct cpuidle_state *idle_state) 2864 { 2865 } 2866 2867 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 2868 { 2869 return NULL; 2870 } 2871 2872 #endif /* !CONFIG_CPU_IDLE */ 2873 2874 extern void schedule_idle(void); 2875 asmlinkage void schedule_user(void); 2876 2877 extern void sysrq_sched_debug_show(void); 2878 extern void sched_init_granularity(void); 2879 extern void update_max_interval(void); 2880 2881 extern void init_sched_dl_class(void); 2882 extern void init_sched_rt_class(void); 2883 extern void init_sched_fair_class(void); 2884 2885 extern void resched_curr(struct rq *rq); 2886 extern void resched_curr_lazy(struct rq *rq); 2887 extern void resched_cpu(int cpu); 2888 2889 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime); 2890 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq); 2891 2892 extern void init_dl_entity(struct sched_dl_entity *dl_se); 2893 2894 extern void init_cfs_throttle_work(struct task_struct *p); 2895 2896 #define BW_SHIFT 20 2897 #define BW_UNIT (1 << BW_SHIFT) 2898 #define RATIO_SHIFT 8 2899 #define MAX_BW_BITS (64 - BW_SHIFT) 2900 #define MAX_BW ((1ULL << MAX_BW_BITS) - 1) 2901 2902 extern unsigned long to_ratio(u64 period, u64 runtime); 2903 2904 extern void init_entity_runnable_average(struct sched_entity *se); 2905 extern void post_init_entity_util_avg(struct task_struct *p); 2906 2907 #ifdef CONFIG_NO_HZ_FULL 2908 extern bool sched_can_stop_tick(struct rq *rq); 2909 extern int __init sched_tick_offload_init(void); 2910 2911 /* 2912 * Tick may be needed by tasks in the runqueue depending on their policy and 2913 * requirements. If tick is needed, lets send the target an IPI to kick it out of 2914 * nohz mode if necessary. 2915 */ 2916 static inline void sched_update_tick_dependency(struct rq *rq) 2917 { 2918 int cpu = cpu_of(rq); 2919 2920 if (!tick_nohz_full_cpu(cpu)) 2921 return; 2922 2923 if (sched_can_stop_tick(rq)) 2924 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED); 2925 else 2926 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED); 2927 } 2928 #else /* !CONFIG_NO_HZ_FULL: */ 2929 static inline int sched_tick_offload_init(void) { return 0; } 2930 static inline void sched_update_tick_dependency(struct rq *rq) { } 2931 #endif /* !CONFIG_NO_HZ_FULL */ 2932 2933 static inline void add_nr_running(struct rq *rq, unsigned count) 2934 { 2935 unsigned prev_nr = rq->nr_running; 2936 2937 rq->nr_running = prev_nr + count; 2938 if (trace_sched_update_nr_running_tp_enabled()) { 2939 call_trace_sched_update_nr_running(rq, count); 2940 } 2941 2942 if (prev_nr < 2 && rq->nr_running >= 2) 2943 set_rd_overloaded(rq->rd, 1); 2944 2945 sched_update_tick_dependency(rq); 2946 } 2947 2948 static inline void sub_nr_running(struct rq *rq, unsigned count) 2949 { 2950 rq->nr_running -= count; 2951 if (trace_sched_update_nr_running_tp_enabled()) { 2952 call_trace_sched_update_nr_running(rq, -count); 2953 } 2954 2955 /* Check if we still need preemption */ 2956 sched_update_tick_dependency(rq); 2957 } 2958 2959 static inline void __block_task(struct rq *rq, struct task_struct *p) 2960 { 2961 if (p->sched_contributes_to_load) 2962 rq->nr_uninterruptible++; 2963 2964 if (p->in_iowait) { 2965 atomic_inc(&rq->nr_iowait); 2966 delayacct_blkio_start(); 2967 } 2968 2969 ASSERT_EXCLUSIVE_WRITER(p->on_rq); 2970 2971 /* 2972 * The moment this write goes through, ttwu() can swoop in and migrate 2973 * this task, rendering our rq->__lock ineffective. 2974 * 2975 * __schedule() try_to_wake_up() 2976 * LOCK rq->__lock LOCK p->pi_lock 2977 * pick_next_task() 2978 * pick_next_task_fair() 2979 * pick_next_entity() 2980 * dequeue_entities() 2981 * __block_task() 2982 * RELEASE p->on_rq = 0 if (p->on_rq && ...) 2983 * break; 2984 * 2985 * ACQUIRE (after ctrl-dep) 2986 * 2987 * cpu = select_task_rq(); 2988 * set_task_cpu(p, cpu); 2989 * ttwu_queue() 2990 * ttwu_do_activate() 2991 * LOCK rq->__lock 2992 * activate_task() 2993 * STORE p->on_rq = 1 2994 * UNLOCK rq->__lock 2995 * 2996 * Callers must ensure to not reference @p after this -- we no longer 2997 * own it. 2998 */ 2999 smp_store_release(&p->on_rq, 0); 3000 } 3001 3002 extern void activate_task(struct rq *rq, struct task_struct *p, int flags); 3003 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags); 3004 3005 extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags); 3006 3007 #ifdef CONFIG_PREEMPT_RT 3008 # define SCHED_NR_MIGRATE_BREAK 8 3009 #else 3010 # define SCHED_NR_MIGRATE_BREAK 32 3011 #endif 3012 3013 extern __read_mostly unsigned int sysctl_sched_nr_migrate; 3014 extern __read_mostly unsigned int sysctl_sched_migration_cost; 3015 3016 extern unsigned int sysctl_sched_base_slice; 3017 3018 extern int sysctl_resched_latency_warn_ms; 3019 extern int sysctl_resched_latency_warn_once; 3020 3021 extern unsigned int sysctl_sched_tunable_scaling; 3022 3023 extern unsigned int sysctl_numa_balancing_scan_delay; 3024 extern unsigned int sysctl_numa_balancing_scan_period_min; 3025 extern unsigned int sysctl_numa_balancing_scan_period_max; 3026 extern unsigned int sysctl_numa_balancing_scan_size; 3027 extern unsigned int sysctl_numa_balancing_hot_threshold; 3028 3029 #ifdef CONFIG_SCHED_HRTICK 3030 3031 /* 3032 * Use hrtick when: 3033 * - enabled by features 3034 * - hrtimer is actually high res 3035 */ 3036 static inline int hrtick_enabled(struct rq *rq) 3037 { 3038 if (!cpu_active(cpu_of(rq))) 3039 return 0; 3040 return hrtimer_is_hres_active(&rq->hrtick_timer); 3041 } 3042 3043 static inline int hrtick_enabled_fair(struct rq *rq) 3044 { 3045 if (!sched_feat(HRTICK)) 3046 return 0; 3047 return hrtick_enabled(rq); 3048 } 3049 3050 static inline int hrtick_enabled_dl(struct rq *rq) 3051 { 3052 if (!sched_feat(HRTICK_DL)) 3053 return 0; 3054 return hrtick_enabled(rq); 3055 } 3056 3057 extern void hrtick_start(struct rq *rq, u64 delay); 3058 3059 #else /* !CONFIG_SCHED_HRTICK: */ 3060 3061 static inline int hrtick_enabled_fair(struct rq *rq) 3062 { 3063 return 0; 3064 } 3065 3066 static inline int hrtick_enabled_dl(struct rq *rq) 3067 { 3068 return 0; 3069 } 3070 3071 static inline int hrtick_enabled(struct rq *rq) 3072 { 3073 return 0; 3074 } 3075 3076 #endif /* !CONFIG_SCHED_HRTICK */ 3077 3078 #ifndef arch_scale_freq_tick 3079 static __always_inline void arch_scale_freq_tick(void) { } 3080 #endif 3081 3082 #ifndef arch_scale_freq_capacity 3083 /** 3084 * arch_scale_freq_capacity - get the frequency scale factor of a given CPU. 3085 * @cpu: the CPU in question. 3086 * 3087 * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e. 3088 * 3089 * f_curr 3090 * ------ * SCHED_CAPACITY_SCALE 3091 * f_max 3092 */ 3093 static __always_inline 3094 unsigned long arch_scale_freq_capacity(int cpu) 3095 { 3096 return SCHED_CAPACITY_SCALE; 3097 } 3098 #endif 3099 3100 /* 3101 * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to 3102 * acquire rq lock instead of rq_lock(). So at the end of these two functions 3103 * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of 3104 * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning. 3105 */ 3106 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) 3107 { 3108 rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 3109 rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 3110 } 3111 3112 #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...) \ 3113 __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__) \ 3114 static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2) \ 3115 __no_context_analysis \ 3116 { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t; \ 3117 _lock; return _t; } 3118 #define DECLARE_LOCK_GUARD_2_ATTRS(_name, _lock, _unlock1, _unlock2) \ 3119 static inline class_##_name##_t class_##_name##_constructor(lock_##_name##_t *_T1, \ 3120 lock_##_name##_t *_T2) _lock; \ 3121 static __always_inline void __class_##_name##_cleanup_ctx1(class_##_name##_t **_T1) \ 3122 __no_context_analysis _unlock1 { } \ 3123 static __always_inline void __class_##_name##_cleanup_ctx2(class_##_name##_t **_T2) \ 3124 __no_context_analysis _unlock2 { } 3125 #define WITH_LOCK_GUARD_2_ATTRS(_name, _T1, _T2) \ 3126 class_##_name##_constructor(_T1, _T2), \ 3127 *__UNIQUE_ID(unlock1) __cleanup(__class_##_name##_cleanup_ctx1) = (void *)(_T1),\ 3128 *__UNIQUE_ID(unlock2) __cleanup(__class_##_name##_cleanup_ctx2) = (void *)(_T2) 3129 3130 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2) 3131 { 3132 #ifdef CONFIG_SCHED_CORE 3133 /* 3134 * In order to not have {0,2},{1,3} turn into into an AB-BA, 3135 * order by core-id first and cpu-id second. 3136 * 3137 * Notably: 3138 * 3139 * double_rq_lock(0,3); will take core-0, core-1 lock 3140 * double_rq_lock(1,2); will take core-1, core-0 lock 3141 * 3142 * when only cpu-id is considered. 3143 */ 3144 if (rq1->core->cpu < rq2->core->cpu) 3145 return true; 3146 if (rq1->core->cpu > rq2->core->cpu) 3147 return false; 3148 3149 /* 3150 * __sched_core_flip() relies on SMT having cpu-id lock order. 3151 */ 3152 #endif /* CONFIG_SCHED_CORE */ 3153 return rq1->cpu < rq2->cpu; 3154 } 3155 3156 extern void double_rq_lock(struct rq *rq1, struct rq *rq2) 3157 __acquires(__rq_lockp(rq1), __rq_lockp(rq2)); 3158 3159 #ifdef CONFIG_PREEMPTION 3160 3161 /* 3162 * fair double_lock_balance: Safely acquires both rq->locks in a fair 3163 * way at the expense of forcing extra atomic operations in all 3164 * invocations. This assures that the double_lock is acquired using the 3165 * same underlying policy as the spinlock_t on this architecture, which 3166 * reduces latency compared to the unfair variant below. However, it 3167 * also adds more overhead and therefore may reduce throughput. 3168 */ 3169 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 3170 __must_hold(__rq_lockp(this_rq)) 3171 __acquires(__rq_lockp(busiest)) 3172 { 3173 raw_spin_rq_unlock(this_rq); 3174 double_rq_lock(this_rq, busiest); 3175 3176 return 1; 3177 } 3178 3179 #else /* !CONFIG_PREEMPTION: */ 3180 /* 3181 * Unfair double_lock_balance: Optimizes throughput at the expense of 3182 * latency by eliminating extra atomic operations when the locks are 3183 * already in proper order on entry. This favors lower CPU-ids and will 3184 * grant the double lock to lower CPUs over higher ids under contention, 3185 * regardless of entry order into the function. 3186 */ 3187 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 3188 __must_hold(__rq_lockp(this_rq)) 3189 __acquires(__rq_lockp(busiest)) 3190 { 3191 if (__rq_lockp(this_rq) == __rq_lockp(busiest)) { 3192 __acquire(__rq_lockp(busiest)); /* already held */ 3193 double_rq_clock_clear_update(this_rq, busiest); 3194 return 0; 3195 } 3196 3197 if (likely(raw_spin_rq_trylock(busiest))) { 3198 double_rq_clock_clear_update(this_rq, busiest); 3199 return 0; 3200 } 3201 3202 if (rq_order_less(this_rq, busiest)) { 3203 raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING); 3204 double_rq_clock_clear_update(this_rq, busiest); 3205 return 0; 3206 } 3207 3208 raw_spin_rq_unlock(this_rq); 3209 double_rq_lock(this_rq, busiest); 3210 3211 return 1; 3212 } 3213 3214 #endif /* !CONFIG_PREEMPTION */ 3215 3216 /* 3217 * double_lock_balance - lock the busiest runqueue, this_rq is locked already. 3218 */ 3219 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest) 3220 __must_hold(__rq_lockp(this_rq)) 3221 __acquires(__rq_lockp(busiest)) 3222 { 3223 lockdep_assert_irqs_disabled(); 3224 3225 return _double_lock_balance(this_rq, busiest); 3226 } 3227 3228 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest) 3229 __releases(__rq_lockp(busiest)) 3230 { 3231 if (__rq_lockp(this_rq) != __rq_lockp(busiest)) 3232 raw_spin_rq_unlock(busiest); 3233 else 3234 __release(__rq_lockp(busiest)); /* fake release */ 3235 lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_); 3236 } 3237 3238 static inline void double_lock(spinlock_t *l1, spinlock_t *l2) 3239 __acquires(l1, l2) 3240 { 3241 if (l1 > l2) 3242 swap(l1, l2); 3243 3244 spin_lock(l1); 3245 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 3246 } 3247 3248 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2) 3249 __acquires(l1, l2) 3250 { 3251 if (l1 > l2) 3252 swap(l1, l2); 3253 3254 spin_lock_irq(l1); 3255 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 3256 } 3257 3258 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2) 3259 __acquires(l1, l2) 3260 { 3261 if (l1 > l2) 3262 swap(l1, l2); 3263 3264 raw_spin_lock(l1); 3265 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 3266 } 3267 3268 static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2) 3269 __releases(l1, l2) 3270 { 3271 raw_spin_unlock(l1); 3272 raw_spin_unlock(l2); 3273 } 3274 3275 DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t, 3276 double_raw_lock(_T->lock, _T->lock2), 3277 double_raw_unlock(_T->lock, _T->lock2)) 3278 3279 DECLARE_LOCK_GUARD_2_ATTRS(double_raw_spinlock, 3280 __acquires(_T1, _T2), 3281 __releases(*(raw_spinlock_t **)_T1), 3282 __releases(*(raw_spinlock_t **)_T2)); 3283 #define class_double_raw_spinlock_constructor(_T1, _T2) \ 3284 WITH_LOCK_GUARD_2_ATTRS(double_raw_spinlock, _T1, _T2) 3285 3286 /* 3287 * double_rq_unlock - safely unlock two runqueues 3288 * 3289 * Note this does not restore interrupts like task_rq_unlock, 3290 * you need to do so manually after calling. 3291 */ 3292 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 3293 __releases(__rq_lockp(rq1), __rq_lockp(rq2)) 3294 { 3295 if (__rq_lockp(rq1) != __rq_lockp(rq2)) 3296 raw_spin_rq_unlock(rq2); 3297 else 3298 __release(__rq_lockp(rq2)); /* fake release */ 3299 raw_spin_rq_unlock(rq1); 3300 } 3301 3302 extern void set_rq_online (struct rq *rq); 3303 extern void set_rq_offline(struct rq *rq); 3304 3305 extern bool sched_smp_initialized; 3306 3307 DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq, 3308 double_rq_lock(_T->lock, _T->lock2), 3309 double_rq_unlock(_T->lock, _T->lock2)) 3310 3311 extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq); 3312 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq); 3313 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq); 3314 3315 extern bool sched_debug_verbose; 3316 3317 extern void print_cfs_stats(struct seq_file *m, int cpu); 3318 extern void print_rt_stats(struct seq_file *m, int cpu); 3319 extern void print_dl_stats(struct seq_file *m, int cpu); 3320 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 3321 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq); 3322 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq); 3323 3324 extern void resched_latency_warn(int cpu, u64 latency); 3325 3326 #ifdef CONFIG_NUMA_BALANCING 3327 extern void show_numa_stats(struct task_struct *p, struct seq_file *m); 3328 extern void 3329 print_numa_stats(struct seq_file *m, int node, unsigned long tsf, 3330 unsigned long tpf, unsigned long gsf, unsigned long gpf); 3331 #endif /* CONFIG_NUMA_BALANCING */ 3332 3333 extern void init_cfs_rq(struct cfs_rq *cfs_rq); 3334 extern void init_rt_rq(struct rt_rq *rt_rq); 3335 extern void init_dl_rq(struct dl_rq *dl_rq); 3336 3337 extern void cfs_bandwidth_usage_inc(void); 3338 extern void cfs_bandwidth_usage_dec(void); 3339 3340 #ifdef CONFIG_NO_HZ_COMMON 3341 3342 #define NOHZ_BALANCE_KICK_BIT 0 3343 #define NOHZ_STATS_KICK_BIT 1 3344 #define NOHZ_NEWILB_KICK_BIT 2 3345 #define NOHZ_NEXT_KICK_BIT 3 3346 3347 /* Run sched_balance_domains() */ 3348 #define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT) 3349 /* Update blocked load */ 3350 #define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT) 3351 /* Update blocked load when entering idle */ 3352 #define NOHZ_NEWILB_KICK BIT(NOHZ_NEWILB_KICK_BIT) 3353 /* Update nohz.next_balance */ 3354 #define NOHZ_NEXT_KICK BIT(NOHZ_NEXT_KICK_BIT) 3355 3356 #define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK) 3357 3358 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags) 3359 3360 extern void nohz_balance_exit_idle(struct rq *rq); 3361 #else /* !CONFIG_NO_HZ_COMMON: */ 3362 static inline void nohz_balance_exit_idle(struct rq *rq) { } 3363 #endif /* !CONFIG_NO_HZ_COMMON */ 3364 3365 #ifdef CONFIG_NO_HZ_COMMON 3366 extern void nohz_run_idle_balance(int cpu); 3367 #else 3368 static inline void nohz_run_idle_balance(int cpu) { } 3369 #endif 3370 3371 #include "stats.h" 3372 3373 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS) 3374 3375 extern void __sched_core_account_forceidle(struct rq *rq); 3376 3377 static inline void sched_core_account_forceidle(struct rq *rq) 3378 { 3379 if (schedstat_enabled()) 3380 __sched_core_account_forceidle(rq); 3381 } 3382 3383 extern void __sched_core_tick(struct rq *rq); 3384 3385 static inline void sched_core_tick(struct rq *rq) 3386 { 3387 if (sched_core_enabled(rq) && schedstat_enabled()) 3388 __sched_core_tick(rq); 3389 } 3390 3391 #else /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS): */ 3392 3393 static inline void sched_core_account_forceidle(struct rq *rq) { } 3394 3395 static inline void sched_core_tick(struct rq *rq) { } 3396 3397 #endif /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS) */ 3398 3399 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 3400 3401 struct irqtime { 3402 u64 total; 3403 u64 tick_delta; 3404 u64 irq_start_time; 3405 struct u64_stats_sync sync; 3406 }; 3407 3408 DECLARE_PER_CPU(struct irqtime, cpu_irqtime); 3409 DECLARE_STATIC_KEY_FALSE(sched_clock_irqtime); 3410 3411 static inline int irqtime_enabled(void) 3412 { 3413 return static_branch_likely(&sched_clock_irqtime); 3414 } 3415 3416 /* 3417 * Returns the irqtime minus the softirq time computed by ksoftirqd. 3418 * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime 3419 * and never move forward. 3420 */ 3421 static inline u64 irq_time_read(int cpu) 3422 { 3423 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu); 3424 unsigned int seq; 3425 u64 total; 3426 3427 do { 3428 seq = __u64_stats_fetch_begin(&irqtime->sync); 3429 total = irqtime->total; 3430 } while (__u64_stats_fetch_retry(&irqtime->sync, seq)); 3431 3432 return total; 3433 } 3434 3435 #else /* !CONFIG_IRQ_TIME_ACCOUNTING: */ 3436 3437 static inline int irqtime_enabled(void) 3438 { 3439 return 0; 3440 } 3441 3442 #endif /* !CONFIG_IRQ_TIME_ACCOUNTING */ 3443 3444 #ifdef CONFIG_CPU_FREQ 3445 3446 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data); 3447 3448 /** 3449 * cpufreq_update_util - Take a note about CPU utilization changes. 3450 * @rq: Runqueue to carry out the update for. 3451 * @flags: Update reason flags. 3452 * 3453 * This function is called by the scheduler on the CPU whose utilization is 3454 * being updated. 3455 * 3456 * It can only be called from RCU-sched read-side critical sections. 3457 * 3458 * The way cpufreq is currently arranged requires it to evaluate the CPU 3459 * performance state (frequency/voltage) on a regular basis to prevent it from 3460 * being stuck in a completely inadequate performance level for too long. 3461 * That is not guaranteed to happen if the updates are only triggered from CFS 3462 * and DL, though, because they may not be coming in if only RT tasks are 3463 * active all the time (or there are RT tasks only). 3464 * 3465 * As a workaround for that issue, this function is called periodically by the 3466 * RT sched class to trigger extra cpufreq updates to prevent it from stalling, 3467 * but that really is a band-aid. Going forward it should be replaced with 3468 * solutions targeted more specifically at RT tasks. 3469 */ 3470 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) 3471 { 3472 struct update_util_data *data; 3473 3474 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data, 3475 cpu_of(rq))); 3476 if (data) 3477 data->func(data, rq_clock(rq), flags); 3478 } 3479 #else /* !CONFIG_CPU_FREQ: */ 3480 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) { } 3481 #endif /* !CONFIG_CPU_FREQ */ 3482 3483 #ifdef arch_scale_freq_capacity 3484 # ifndef arch_scale_freq_invariant 3485 # define arch_scale_freq_invariant() true 3486 # endif 3487 #else 3488 # define arch_scale_freq_invariant() false 3489 #endif 3490 3491 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs, 3492 unsigned long *min, 3493 unsigned long *max); 3494 3495 unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual, 3496 unsigned long min, 3497 unsigned long max); 3498 3499 3500 /* 3501 * Verify the fitness of task @p to run on @cpu taking into account the 3502 * CPU original capacity and the runtime/deadline ratio of the task. 3503 * 3504 * The function will return true if the original capacity of @cpu is 3505 * greater than or equal to task's deadline density right shifted by 3506 * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise. 3507 */ 3508 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu) 3509 { 3510 unsigned long cap = arch_scale_cpu_capacity(cpu); 3511 3512 return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT); 3513 } 3514 3515 static inline unsigned long cpu_bw_dl(struct rq *rq) 3516 { 3517 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT; 3518 } 3519 3520 static inline unsigned long cpu_util_dl(struct rq *rq) 3521 { 3522 return READ_ONCE(rq->avg_dl.util_avg); 3523 } 3524 3525 3526 extern unsigned long cpu_util_cfs(int cpu); 3527 extern unsigned long cpu_util_cfs_boost(int cpu); 3528 3529 static inline unsigned long cpu_util_rt(struct rq *rq) 3530 { 3531 return READ_ONCE(rq->avg_rt.util_avg); 3532 } 3533 3534 #ifdef CONFIG_UCLAMP_TASK 3535 3536 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id); 3537 3538 /* 3539 * When uclamp is compiled in, the aggregation at rq level is 'turned off' 3540 * by default in the fast path and only gets turned on once userspace performs 3541 * an operation that requires it. 3542 * 3543 * Returns true if userspace opted-in to use uclamp and aggregation at rq level 3544 * hence is active. 3545 */ 3546 static inline bool uclamp_is_used(void) 3547 { 3548 return static_branch_likely(&sched_uclamp_used); 3549 } 3550 3551 /* 3552 * Enabling static branches would get the cpus_read_lock(), 3553 * check whether uclamp_is_used before enable it to avoid always 3554 * calling cpus_read_lock(). Because we never disable this 3555 * static key once enable it. 3556 */ 3557 static inline void sched_uclamp_enable(void) 3558 { 3559 if (!uclamp_is_used()) 3560 static_branch_enable(&sched_uclamp_used); 3561 } 3562 3563 static inline unsigned long uclamp_rq_get(struct rq *rq, 3564 enum uclamp_id clamp_id) 3565 { 3566 return READ_ONCE(rq->uclamp[clamp_id].value); 3567 } 3568 3569 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, 3570 unsigned int value) 3571 { 3572 WRITE_ONCE(rq->uclamp[clamp_id].value, value); 3573 } 3574 3575 static inline bool uclamp_rq_is_idle(struct rq *rq) 3576 { 3577 return rq->uclamp_flags & UCLAMP_FLAG_IDLE; 3578 } 3579 3580 /* Is the rq being capped/throttled by uclamp_max? */ 3581 static inline bool uclamp_rq_is_capped(struct rq *rq) 3582 { 3583 unsigned long rq_util; 3584 unsigned long max_util; 3585 3586 if (!uclamp_is_used()) 3587 return false; 3588 3589 rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq); 3590 max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value); 3591 3592 return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util; 3593 } 3594 3595 #define for_each_clamp_id(clamp_id) \ 3596 for ((clamp_id) = 0; (clamp_id) < UCLAMP_CNT; (clamp_id)++) 3597 3598 extern unsigned int sysctl_sched_uclamp_util_min_rt_default; 3599 3600 3601 static inline unsigned int uclamp_none(enum uclamp_id clamp_id) 3602 { 3603 if (clamp_id == UCLAMP_MIN) 3604 return 0; 3605 return SCHED_CAPACITY_SCALE; 3606 } 3607 3608 /* Integer rounded range for each bucket */ 3609 #define UCLAMP_BUCKET_DELTA DIV_ROUND_CLOSEST(SCHED_CAPACITY_SCALE, UCLAMP_BUCKETS) 3610 3611 static inline unsigned int uclamp_bucket_id(unsigned int clamp_value) 3612 { 3613 return min_t(unsigned int, clamp_value / UCLAMP_BUCKET_DELTA, UCLAMP_BUCKETS - 1); 3614 } 3615 3616 static inline void 3617 uclamp_se_set(struct uclamp_se *uc_se, unsigned int value, bool user_defined) 3618 { 3619 uc_se->value = value; 3620 uc_se->bucket_id = uclamp_bucket_id(value); 3621 uc_se->user_defined = user_defined; 3622 } 3623 3624 #else /* !CONFIG_UCLAMP_TASK: */ 3625 3626 static inline unsigned long 3627 uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id) 3628 { 3629 if (clamp_id == UCLAMP_MIN) 3630 return 0; 3631 3632 return SCHED_CAPACITY_SCALE; 3633 } 3634 3635 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; } 3636 3637 static inline bool uclamp_is_used(void) 3638 { 3639 return false; 3640 } 3641 3642 static inline void sched_uclamp_enable(void) {} 3643 3644 static inline unsigned long 3645 uclamp_rq_get(struct rq *rq, enum uclamp_id clamp_id) 3646 { 3647 if (clamp_id == UCLAMP_MIN) 3648 return 0; 3649 3650 return SCHED_CAPACITY_SCALE; 3651 } 3652 3653 static inline void 3654 uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, unsigned int value) 3655 { 3656 } 3657 3658 static inline bool uclamp_rq_is_idle(struct rq *rq) 3659 { 3660 return false; 3661 } 3662 3663 #endif /* !CONFIG_UCLAMP_TASK */ 3664 3665 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 3666 3667 static inline unsigned long cpu_util_irq(struct rq *rq) 3668 { 3669 return READ_ONCE(rq->avg_irq.util_avg); 3670 } 3671 3672 static inline 3673 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 3674 { 3675 util *= (max - irq); 3676 util /= max; 3677 3678 return util; 3679 3680 } 3681 3682 #else /* !CONFIG_HAVE_SCHED_AVG_IRQ: */ 3683 3684 static inline unsigned long cpu_util_irq(struct rq *rq) 3685 { 3686 return 0; 3687 } 3688 3689 static inline 3690 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 3691 { 3692 return util; 3693 } 3694 3695 #endif /* !CONFIG_HAVE_SCHED_AVG_IRQ */ 3696 3697 extern void __setparam_fair(struct task_struct *p, const struct sched_attr *attr); 3698 3699 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) 3700 3701 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus))) 3702 3703 DECLARE_STATIC_KEY_FALSE(sched_energy_present); 3704 3705 static inline bool sched_energy_enabled(void) 3706 { 3707 return static_branch_unlikely(&sched_energy_present); 3708 } 3709 3710 #else /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL): */ 3711 3712 #define perf_domain_span(pd) NULL 3713 3714 static inline bool sched_energy_enabled(void) { return false; } 3715 3716 #endif /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */ 3717 3718 #ifdef CONFIG_MEMBARRIER 3719 3720 /* 3721 * The scheduler provides memory barriers required by membarrier between: 3722 * - prior user-space memory accesses and store to rq->membarrier_state, 3723 * - store to rq->membarrier_state and following user-space memory accesses. 3724 * In the same way it provides those guarantees around store to rq->curr. 3725 */ 3726 static inline void membarrier_switch_mm(struct rq *rq, 3727 struct mm_struct *prev_mm, 3728 struct mm_struct *next_mm) 3729 { 3730 int membarrier_state; 3731 3732 if (prev_mm == next_mm) 3733 return; 3734 3735 membarrier_state = atomic_read(&next_mm->membarrier_state); 3736 if (READ_ONCE(rq->membarrier_state) == membarrier_state) 3737 return; 3738 3739 WRITE_ONCE(rq->membarrier_state, membarrier_state); 3740 } 3741 3742 #else /* !CONFIG_MEMBARRIER: */ 3743 3744 static inline void membarrier_switch_mm(struct rq *rq, 3745 struct mm_struct *prev_mm, 3746 struct mm_struct *next_mm) 3747 { 3748 } 3749 3750 #endif /* !CONFIG_MEMBARRIER */ 3751 3752 static inline bool is_per_cpu_kthread(struct task_struct *p) 3753 { 3754 if (!(p->flags & PF_KTHREAD)) 3755 return false; 3756 3757 if (p->nr_cpus_allowed != 1) 3758 return false; 3759 3760 return true; 3761 } 3762 3763 extern void swake_up_all_locked(struct swait_queue_head *q); 3764 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait); 3765 3766 extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags); 3767 3768 #ifdef CONFIG_PREEMPT_DYNAMIC 3769 extern int preempt_dynamic_mode; 3770 extern int sched_dynamic_mode(const char *str); 3771 extern void sched_dynamic_update(int mode); 3772 #endif 3773 extern const char *preempt_modes[]; 3774 3775 #ifdef CONFIG_SCHED_MM_CID 3776 3777 static __always_inline bool cid_on_cpu(unsigned int cid) 3778 { 3779 return cid & MM_CID_ONCPU; 3780 } 3781 3782 static __always_inline bool cid_in_transit(unsigned int cid) 3783 { 3784 return cid & MM_CID_TRANSIT; 3785 } 3786 3787 static __always_inline unsigned int cpu_cid_to_cid(unsigned int cid) 3788 { 3789 return cid & ~MM_CID_ONCPU; 3790 } 3791 3792 static __always_inline unsigned int cid_to_cpu_cid(unsigned int cid) 3793 { 3794 return cid | MM_CID_ONCPU; 3795 } 3796 3797 static __always_inline unsigned int cid_to_transit_cid(unsigned int cid) 3798 { 3799 return cid | MM_CID_TRANSIT; 3800 } 3801 3802 static __always_inline unsigned int cid_from_transit_cid(unsigned int cid) 3803 { 3804 return cid & ~MM_CID_TRANSIT; 3805 } 3806 3807 static __always_inline bool cid_on_task(unsigned int cid) 3808 { 3809 /* True if none of the MM_CID_ONCPU, MM_CID_TRANSIT, MM_CID_UNSET bits is set */ 3810 return cid < MM_CID_TRANSIT; 3811 } 3812 3813 static __always_inline void mm_drop_cid(struct mm_struct *mm, unsigned int cid) 3814 { 3815 clear_bit(cid, mm_cidmask(mm)); 3816 } 3817 3818 static __always_inline void mm_unset_cid_on_task(struct task_struct *t) 3819 { 3820 unsigned int cid = t->mm_cid.cid; 3821 3822 t->mm_cid.cid = MM_CID_UNSET; 3823 if (cid_on_task(cid)) 3824 mm_drop_cid(t->mm, cid); 3825 } 3826 3827 static __always_inline void mm_drop_cid_on_cpu(struct mm_struct *mm, struct mm_cid_pcpu *pcp) 3828 { 3829 /* Clear the ONCPU bit, but do not set UNSET in the per CPU storage */ 3830 if (cid_on_cpu(pcp->cid)) { 3831 pcp->cid = cpu_cid_to_cid(pcp->cid); 3832 mm_drop_cid(mm, pcp->cid); 3833 } 3834 } 3835 3836 static inline unsigned int __mm_get_cid(struct mm_struct *mm, unsigned int max_cids) 3837 { 3838 unsigned int cid = find_first_zero_bit(mm_cidmask(mm), max_cids); 3839 3840 if (cid >= max_cids) 3841 return MM_CID_UNSET; 3842 if (test_and_set_bit(cid, mm_cidmask(mm))) 3843 return MM_CID_UNSET; 3844 return cid; 3845 } 3846 3847 static inline unsigned int mm_get_cid(struct mm_struct *mm) 3848 { 3849 unsigned int cid = __mm_get_cid(mm, READ_ONCE(mm->mm_cid.max_cids)); 3850 3851 while (cid == MM_CID_UNSET) { 3852 cpu_relax(); 3853 cid = __mm_get_cid(mm, num_possible_cpus()); 3854 } 3855 return cid; 3856 } 3857 3858 static inline unsigned int mm_cid_converge(struct mm_struct *mm, unsigned int orig_cid, 3859 unsigned int max_cids) 3860 { 3861 unsigned int new_cid, cid = cpu_cid_to_cid(orig_cid); 3862 3863 /* Is it in the optimal CID space? */ 3864 if (likely(cid < max_cids)) 3865 return orig_cid; 3866 3867 /* Try to find one in the optimal space. Otherwise keep the provided. */ 3868 new_cid = __mm_get_cid(mm, max_cids); 3869 if (new_cid != MM_CID_UNSET) { 3870 mm_drop_cid(mm, cid); 3871 /* Preserve the ONCPU mode of the original CID */ 3872 return new_cid | (orig_cid & MM_CID_ONCPU); 3873 } 3874 return orig_cid; 3875 } 3876 3877 static __always_inline void mm_cid_update_task_cid(struct task_struct *t, unsigned int cid) 3878 { 3879 if (t->mm_cid.cid != cid) { 3880 t->mm_cid.cid = cid; 3881 rseq_sched_set_ids_changed(t); 3882 } 3883 } 3884 3885 static __always_inline void mm_cid_update_pcpu_cid(struct mm_struct *mm, unsigned int cid) 3886 { 3887 __this_cpu_write(mm->mm_cid.pcpu->cid, cid); 3888 } 3889 3890 static __always_inline void mm_cid_from_cpu(struct task_struct *t, unsigned int cpu_cid, 3891 unsigned int mode) 3892 { 3893 unsigned int max_cids, tcid = t->mm_cid.cid; 3894 struct mm_struct *mm = t->mm; 3895 3896 max_cids = READ_ONCE(mm->mm_cid.max_cids); 3897 /* Optimize for the common case where both have the ONCPU bit set */ 3898 if (likely(cid_on_cpu(cpu_cid & tcid))) { 3899 if (likely(cpu_cid_to_cid(cpu_cid) < max_cids)) { 3900 mm_cid_update_task_cid(t, cpu_cid); 3901 return; 3902 } 3903 /* Try to converge into the optimal CID space */ 3904 cpu_cid = mm_cid_converge(mm, cpu_cid, max_cids); 3905 } else { 3906 /* Hand over or drop the task owned CID */ 3907 if (cid_on_task(tcid)) { 3908 if (cid_on_cpu(cpu_cid)) 3909 mm_unset_cid_on_task(t); 3910 else 3911 cpu_cid = cid_to_cpu_cid(tcid); 3912 } 3913 /* Still nothing, allocate a new one */ 3914 if (!cid_on_cpu(cpu_cid)) 3915 cpu_cid = cid_to_cpu_cid(mm_get_cid(mm)); 3916 3917 /* Handle the transition mode flag if required */ 3918 if (mode & MM_CID_TRANSIT) 3919 cpu_cid = cpu_cid_to_cid(cpu_cid) | MM_CID_TRANSIT; 3920 } 3921 mm_cid_update_pcpu_cid(mm, cpu_cid); 3922 mm_cid_update_task_cid(t, cpu_cid); 3923 } 3924 3925 static __always_inline void mm_cid_from_task(struct task_struct *t, unsigned int cpu_cid, 3926 unsigned int mode) 3927 { 3928 unsigned int max_cids, tcid = t->mm_cid.cid; 3929 struct mm_struct *mm = t->mm; 3930 3931 max_cids = READ_ONCE(mm->mm_cid.max_cids); 3932 /* Optimize for the common case, where both have the ONCPU bit clear */ 3933 if (likely(cid_on_task(tcid | cpu_cid))) { 3934 if (likely(tcid < max_cids)) { 3935 mm_cid_update_pcpu_cid(mm, tcid); 3936 return; 3937 } 3938 /* Try to converge into the optimal CID space */ 3939 tcid = mm_cid_converge(mm, tcid, max_cids); 3940 } else { 3941 /* Hand over or drop the CPU owned CID */ 3942 if (cid_on_cpu(cpu_cid)) { 3943 if (cid_on_task(tcid)) 3944 mm_drop_cid_on_cpu(mm, this_cpu_ptr(mm->mm_cid.pcpu)); 3945 else 3946 tcid = cpu_cid_to_cid(cpu_cid); 3947 } 3948 /* Still nothing, allocate a new one */ 3949 if (!cid_on_task(tcid)) 3950 tcid = mm_get_cid(mm); 3951 /* Set the transition mode flag if required */ 3952 tcid |= mode & MM_CID_TRANSIT; 3953 } 3954 mm_cid_update_pcpu_cid(mm, tcid); 3955 mm_cid_update_task_cid(t, tcid); 3956 } 3957 3958 static __always_inline void mm_cid_schedin(struct task_struct *next) 3959 { 3960 struct mm_struct *mm = next->mm; 3961 unsigned int cpu_cid, mode; 3962 3963 if (!next->mm_cid.active) 3964 return; 3965 3966 cpu_cid = __this_cpu_read(mm->mm_cid.pcpu->cid); 3967 mode = READ_ONCE(mm->mm_cid.mode); 3968 if (likely(!cid_on_cpu(mode))) 3969 mm_cid_from_task(next, cpu_cid, mode); 3970 else 3971 mm_cid_from_cpu(next, cpu_cid, mode); 3972 } 3973 3974 static __always_inline void mm_cid_schedout(struct task_struct *prev) 3975 { 3976 struct mm_struct *mm = prev->mm; 3977 unsigned int mode, cid; 3978 3979 /* During mode transitions CIDs are temporary and need to be dropped */ 3980 if (likely(!cid_in_transit(prev->mm_cid.cid))) 3981 return; 3982 3983 mode = READ_ONCE(mm->mm_cid.mode); 3984 cid = cid_from_transit_cid(prev->mm_cid.cid); 3985 3986 /* 3987 * If transition mode is done, transfer ownership when the CID is 3988 * within the convergence range to optimize the next schedule in. 3989 */ 3990 if (!cid_in_transit(mode) && cid < READ_ONCE(mm->mm_cid.max_cids)) { 3991 if (cid_on_cpu(mode)) 3992 cid = cid_to_cpu_cid(cid); 3993 3994 /* Update both so that the next schedule in goes into the fast path */ 3995 mm_cid_update_pcpu_cid(mm, cid); 3996 prev->mm_cid.cid = cid; 3997 } else { 3998 mm_drop_cid(mm, cid); 3999 prev->mm_cid.cid = MM_CID_UNSET; 4000 } 4001 } 4002 4003 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next) 4004 { 4005 mm_cid_schedout(prev); 4006 mm_cid_schedin(next); 4007 } 4008 4009 #else /* !CONFIG_SCHED_MM_CID: */ 4010 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next) { } 4011 #endif /* !CONFIG_SCHED_MM_CID */ 4012 4013 extern u64 avg_vruntime(struct cfs_rq *cfs_rq); 4014 extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se); 4015 static inline 4016 void move_queued_task_locked(struct rq *src_rq, struct rq *dst_rq, struct task_struct *task) 4017 { 4018 lockdep_assert_rq_held(src_rq); 4019 lockdep_assert_rq_held(dst_rq); 4020 4021 deactivate_task(src_rq, task, 0); 4022 set_task_cpu(task, dst_rq->cpu); 4023 activate_task(dst_rq, task, 0); 4024 wakeup_preempt(dst_rq, task, 0); 4025 } 4026 4027 static inline 4028 bool task_is_pushable(struct rq *rq, struct task_struct *p, int cpu) 4029 { 4030 if (!task_on_cpu(rq, p) && 4031 cpumask_test_cpu(cpu, &p->cpus_mask)) 4032 return true; 4033 4034 return false; 4035 } 4036 4037 #ifdef CONFIG_RT_MUTEXES 4038 4039 static inline int __rt_effective_prio(struct task_struct *pi_task, int prio) 4040 { 4041 if (pi_task) 4042 prio = min(prio, pi_task->prio); 4043 4044 return prio; 4045 } 4046 4047 static inline int rt_effective_prio(struct task_struct *p, int prio) 4048 { 4049 struct task_struct *pi_task = rt_mutex_get_top_task(p); 4050 4051 return __rt_effective_prio(pi_task, prio); 4052 } 4053 4054 #else /* !CONFIG_RT_MUTEXES: */ 4055 4056 static inline int rt_effective_prio(struct task_struct *p, int prio) 4057 { 4058 return prio; 4059 } 4060 4061 #endif /* !CONFIG_RT_MUTEXES */ 4062 4063 extern int __sched_setscheduler(struct task_struct *p, const struct sched_attr *attr, bool user, bool pi); 4064 extern int __sched_setaffinity(struct task_struct *p, struct affinity_context *ctx); 4065 extern const struct sched_class *__setscheduler_class(int policy, int prio); 4066 extern void set_load_weight(struct task_struct *p, bool update_load); 4067 extern void enqueue_task(struct rq *rq, struct task_struct *p, int flags); 4068 extern bool dequeue_task(struct rq *rq, struct task_struct *p, int flags); 4069 4070 extern struct balance_callback *splice_balance_callbacks(struct rq *rq); 4071 4072 extern void __balance_callbacks(struct rq *rq, struct rq_flags *rf); 4073 extern void balance_callbacks(struct rq *rq, struct balance_callback *head); 4074 4075 /* 4076 * The 'sched_change' pattern is the safe, easy and slow way of changing a 4077 * task's scheduling properties. It dequeues a task, such that the scheduler 4078 * is fully unaware of it; at which point its properties can be modified; 4079 * after which it is enqueued again. 4080 * 4081 * Typically this must be called while holding task_rq_lock, since most/all 4082 * properties are serialized under those locks. There is currently one 4083 * exception to this rule in sched/ext which only holds rq->lock. 4084 */ 4085 4086 /* 4087 * This structure is a temporary, used to preserve/convey the queueing state 4088 * of the task between sched_change_begin() and sched_change_end(). Ensuring 4089 * the task's queueing state is idempotent across the operation. 4090 */ 4091 struct sched_change_ctx { 4092 u64 prio; 4093 struct task_struct *p; 4094 const struct sched_class *class; 4095 int flags; 4096 bool queued; 4097 bool running; 4098 }; 4099 4100 struct sched_change_ctx *sched_change_begin(struct task_struct *p, unsigned int flags); 4101 void sched_change_end(struct sched_change_ctx *ctx); 4102 4103 DEFINE_CLASS(sched_change, struct sched_change_ctx *, 4104 sched_change_end(_T), 4105 sched_change_begin(p, flags), 4106 struct task_struct *p, unsigned int flags) 4107 4108 DEFINE_CLASS_IS_UNCONDITIONAL(sched_change) 4109 4110 #include "ext.h" 4111 4112 #endif /* _KERNEL_SCHED_SCHED_H */ 4113