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