1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Scheduler internal types and methods: 4 */ 5 #ifndef _KERNEL_SCHED_SCHED_H 6 #define _KERNEL_SCHED_SCHED_H 7 8 #include <linux/prandom.h> 9 #include <linux/sched/affinity.h> 10 #include <linux/sched/autogroup.h> 11 #include <linux/sched/cpufreq.h> 12 #include <linux/sched/deadline.h> 13 #include <linux/sched.h> 14 #include <linux/sched/loadavg.h> 15 #include <linux/sched/mm.h> 16 #include <linux/sched/rseq_api.h> 17 #include <linux/sched/signal.h> 18 #include <linux/sched/smt.h> 19 #include <linux/sched/stat.h> 20 #include <linux/sched/sysctl.h> 21 #include <linux/sched/task_flags.h> 22 #include <linux/sched/task.h> 23 #include <linux/sched/topology.h> 24 #include <linux/atomic.h> 25 #include <linux/bitmap.h> 26 #include <linux/bug.h> 27 #include <linux/capability.h> 28 #include <linux/cgroup_api.h> 29 #include <linux/cgroup.h> 30 #include <linux/context_tracking.h> 31 #include <linux/cpufreq.h> 32 #include <linux/cpumask_api.h> 33 #include <linux/cpuset.h> 34 #include <linux/ctype.h> 35 #include <linux/file.h> 36 #include <linux/fs_api.h> 37 #include <linux/hrtimer_api.h> 38 #include <linux/interrupt.h> 39 #include <linux/irq_work.h> 40 #include <linux/jiffies.h> 41 #include <linux/kref_api.h> 42 #include <linux/kthread.h> 43 #include <linux/ktime_api.h> 44 #include <linux/lockdep_api.h> 45 #include <linux/lockdep.h> 46 #include <linux/memblock.h> 47 #include <linux/memcontrol.h> 48 #include <linux/minmax.h> 49 #include <linux/mm.h> 50 #include <linux/module.h> 51 #include <linux/mutex_api.h> 52 #include <linux/plist.h> 53 #include <linux/poll.h> 54 #include <linux/proc_fs.h> 55 #include <linux/profile.h> 56 #include <linux/psi.h> 57 #include <linux/rcupdate.h> 58 #include <linux/seq_file.h> 59 #include <linux/seqlock.h> 60 #include <linux/softirq.h> 61 #include <linux/spinlock_api.h> 62 #include <linux/static_key.h> 63 #include <linux/stop_machine.h> 64 #include <linux/syscalls_api.h> 65 #include <linux/syscalls.h> 66 #include <linux/tick.h> 67 #include <linux/topology.h> 68 #include <linux/types.h> 69 #include <linux/u64_stats_sync_api.h> 70 #include <linux/uaccess.h> 71 #include <linux/vmstat.h> 72 #include <linux/wait_api.h> 73 #include <linux/wait_bit.h> 74 #include <linux/workqueue_api.h> 75 #include <linux/delayacct.h> 76 #include <linux/mmu_context.h> 77 78 #include <trace/events/power.h> 79 #include <trace/events/sched.h> 80 81 #include "../workqueue_internal.h" 82 83 struct rq; 84 struct cfs_rq; 85 struct rt_rq; 86 struct sched_group; 87 struct cpuidle_state; 88 89 #if defined(CONFIG_PARAVIRT) && !defined(CONFIG_HAVE_PV_STEAL_CLOCK_GEN) 90 # include <asm/paravirt.h> 91 #endif 92 93 #include <asm/barrier.h> 94 95 #include "cpupri.h" 96 #include "cpudeadline.h" 97 98 /* task_struct::on_rq states: */ 99 #define TASK_ON_RQ_QUEUED 1 100 #define TASK_ON_RQ_MIGRATING 2 101 102 extern __read_mostly int scheduler_running; 103 104 extern unsigned long calc_load_update; 105 extern atomic_long_t calc_load_tasks; 106 107 extern void calc_global_load_tick(struct rq *this_rq); 108 extern long calc_load_fold_active(struct rq *this_rq, long adjust); 109 110 extern void call_trace_sched_update_nr_running(struct rq *rq, int count); 111 112 extern int sysctl_sched_rt_period; 113 extern int sysctl_sched_rt_runtime; 114 extern int sched_rr_timeslice; 115 116 /* 117 * Asymmetric CPU capacity bits 118 */ 119 struct asym_cap_data { 120 struct list_head link; 121 struct rcu_head rcu; 122 unsigned long capacity; 123 unsigned long cpus[]; 124 }; 125 126 extern struct list_head asym_cap_list; 127 128 #define cpu_capacity_span(asym_data) to_cpumask((asym_data)->cpus) 129 130 /* 131 * Helpers for converting nanosecond timing to jiffy resolution 132 */ 133 #define NS_TO_JIFFIES(time) ((unsigned long)(time) / (NSEC_PER_SEC/HZ)) 134 135 /* 136 * Increase resolution of nice-level calculations for 64-bit architectures. 137 * The extra resolution improves shares distribution and load balancing of 138 * low-weight task groups (eg. nice +19 on an autogroup), deeper task-group 139 * hierarchies, especially on larger systems. This is not a user-visible change 140 * and does not change the user-interface for setting shares/weights. 141 * 142 * We increase resolution only if we have enough bits to allow this increased 143 * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit 144 * are pretty high and the returns do not justify the increased costs. 145 * 146 * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to 147 * increase coverage and consistency always enable it on 64-bit platforms. 148 */ 149 #ifdef CONFIG_64BIT 150 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT) 151 # define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT) 152 # define scale_load_down(w) \ 153 ({ \ 154 unsigned long __w = (w); \ 155 \ 156 if (__w) \ 157 __w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \ 158 __w; \ 159 }) 160 #else 161 # define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT) 162 # define scale_load(w) (w) 163 # define scale_load_down(w) (w) 164 #endif 165 166 /* 167 * Task weight (visible to users) and its load (invisible to users) have 168 * independent resolution, but they should be well calibrated. We use 169 * scale_load() and scale_load_down(w) to convert between them. The 170 * following must be true: 171 * 172 * scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD 173 * 174 */ 175 #define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT) 176 177 /* 178 * Single value that decides SCHED_DEADLINE internal math precision. 179 * 10 -> just above 1us 180 * 9 -> just above 0.5us 181 */ 182 #define DL_SCALE 10 183 184 /* 185 * Single value that denotes runtime == period, ie unlimited time. 186 */ 187 #define RUNTIME_INF ((u64)~0ULL) 188 189 static inline int idle_policy(int policy) 190 { 191 return policy == SCHED_IDLE; 192 } 193 194 static inline int normal_policy(int policy) 195 { 196 #ifdef CONFIG_SCHED_CLASS_EXT 197 if (policy == SCHED_EXT) 198 return true; 199 #endif 200 return policy == SCHED_NORMAL; 201 } 202 203 static inline int fair_policy(int policy) 204 { 205 return normal_policy(policy) || policy == SCHED_BATCH; 206 } 207 208 static inline int rt_policy(int policy) 209 { 210 return policy == SCHED_FIFO || policy == SCHED_RR; 211 } 212 213 static inline int dl_policy(int policy) 214 { 215 return policy == SCHED_DEADLINE; 216 } 217 218 static inline bool valid_policy(int policy) 219 { 220 return idle_policy(policy) || fair_policy(policy) || 221 rt_policy(policy) || dl_policy(policy); 222 } 223 224 static inline int task_has_idle_policy(struct task_struct *p) 225 { 226 return idle_policy(p->policy); 227 } 228 229 static inline int task_has_rt_policy(struct task_struct *p) 230 { 231 return rt_policy(p->policy); 232 } 233 234 static inline int task_has_dl_policy(struct task_struct *p) 235 { 236 return dl_policy(p->policy); 237 } 238 239 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT) 240 241 static inline void update_avg(u64 *avg, u64 sample) 242 { 243 s64 diff = sample - *avg; 244 245 *avg += diff / 8; 246 } 247 248 /* 249 * Shifting a value by an exponent greater *or equal* to the size of said value 250 * is UB; cap at size-1. 251 */ 252 #define shr_bound(val, shift) \ 253 (val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1)) 254 255 /* 256 * cgroup weight knobs should use the common MIN, DFL and MAX values which are 257 * 1, 100 and 10000 respectively. While it loses a bit of range on both ends, it 258 * maps pretty well onto the shares value used by scheduler and the round-trip 259 * conversions preserve the original value over the entire range. 260 */ 261 static inline unsigned long sched_weight_from_cgroup(unsigned long cgrp_weight) 262 { 263 return DIV_ROUND_CLOSEST_ULL(cgrp_weight * 1024, CGROUP_WEIGHT_DFL); 264 } 265 266 static inline unsigned long sched_weight_to_cgroup(unsigned long weight) 267 { 268 return clamp_t(unsigned long, 269 DIV_ROUND_CLOSEST_ULL(weight * CGROUP_WEIGHT_DFL, 1024), 270 CGROUP_WEIGHT_MIN, CGROUP_WEIGHT_MAX); 271 } 272 273 /* 274 * !! For sched_setattr_nocheck() (kernel) only !! 275 * 276 * This is actually gross. :( 277 * 278 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE 279 * tasks, but still be able to sleep. We need this on platforms that cannot 280 * atomically change clock frequency. Remove once fast switching will be 281 * available on such platforms. 282 * 283 * SUGOV stands for SchedUtil GOVernor. 284 */ 285 #define SCHED_FLAG_SUGOV 0x10000000 286 287 #define SCHED_DL_FLAGS (SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV) 288 289 static inline bool dl_entity_is_special(const struct sched_dl_entity *dl_se) 290 { 291 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL 292 return unlikely(dl_se->flags & SCHED_FLAG_SUGOV); 293 #else 294 return false; 295 #endif 296 } 297 298 /* 299 * Tells if entity @a should preempt entity @b. 300 */ 301 static inline bool dl_entity_preempt(const struct sched_dl_entity *a, 302 const struct sched_dl_entity *b) 303 { 304 return dl_entity_is_special(a) || 305 dl_time_before(a->deadline, b->deadline); 306 } 307 308 /* 309 * This is the priority-queue data structure of the RT scheduling class: 310 */ 311 struct rt_prio_array { 312 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */ 313 struct list_head queue[MAX_RT_PRIO]; 314 }; 315 316 struct rt_bandwidth { 317 /* nests inside the rq lock: */ 318 raw_spinlock_t rt_runtime_lock; 319 ktime_t rt_period; 320 u64 rt_runtime; 321 struct hrtimer rt_period_timer; 322 unsigned int rt_period_active; 323 }; 324 325 static inline int dl_bandwidth_enabled(void) 326 { 327 return sysctl_sched_rt_runtime >= 0; 328 } 329 330 /* 331 * To keep the bandwidth of -deadline tasks under control 332 * we need some place where: 333 * - store the maximum -deadline bandwidth of each cpu; 334 * - cache the fraction of bandwidth that is currently allocated in 335 * each root domain; 336 * 337 * This is all done in the data structure below. It is similar to the 338 * one used for RT-throttling (rt_bandwidth), with the main difference 339 * that, since here we are only interested in admission control, we 340 * do not decrease any runtime while the group "executes", neither we 341 * need a timer to replenish it. 342 * 343 * With respect to SMP, bandwidth is given on a per root domain basis, 344 * meaning that: 345 * - bw (< 100%) is the deadline bandwidth of each CPU; 346 * - total_bw is the currently allocated bandwidth in each root domain; 347 */ 348 struct dl_bw { 349 raw_spinlock_t lock; 350 u64 bw; 351 u64 total_bw; 352 }; 353 354 extern void init_dl_bw(struct dl_bw *dl_b); 355 extern int sched_dl_global_validate(void); 356 extern void sched_dl_do_global(void); 357 extern int sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr); 358 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr); 359 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr, unsigned int flags); 360 extern bool __checkparam_dl(const struct sched_attr *attr); 361 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr); 362 extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 363 extern int dl_bw_deactivate(int cpu); 364 extern s64 dl_scaled_delta_exec(struct rq *rq, struct sched_dl_entity *dl_se, s64 delta_exec); 365 /* 366 * SCHED_DEADLINE supports servers (nested scheduling) with the following 367 * interface: 368 * 369 * dl_se::rq -- runqueue we belong to. 370 * 371 * dl_se::server_pick() -- nested pick_next_task(); we yield the period if this 372 * returns NULL. 373 * 374 * dl_server_update() -- called from update_curr_common(), propagates runtime 375 * to the server. 376 * 377 * dl_server_start() -- start the server when it has tasks; it will stop 378 * automatically when there are no more tasks, per 379 * dl_se::server_pick() returning NULL. 380 * 381 * dl_server_stop() -- (force) stop the server; use when updating 382 * parameters. 383 * 384 * dl_server_init() -- initializes the server. 385 * 386 * When started the dl_server will (per dl_defer) schedule a timer for its 387 * zero-laxity point -- that is, unlike regular EDF tasks which run ASAP, a 388 * server will run at the very end of its period. 389 * 390 * This is done such that any runtime from the target class can be accounted 391 * against the server -- through dl_server_update() above -- such that when it 392 * becomes time to run, it might already be out of runtime and get deferred 393 * until the next period. In this case dl_server_timer() will alternate 394 * between defer and replenish but never actually enqueue the server. 395 * 396 * Only when the target class does not manage to exhaust the server's runtime 397 * (there's actualy starvation in the given period), will the dl_server get on 398 * the runqueue. Once queued it will pick tasks from the target class and run 399 * them until either its runtime is exhaused, at which point its back to 400 * dl_server_timer, or until there are no more tasks to run, at which point 401 * the dl_server stops itself. 402 * 403 * By stopping at this point the dl_server retains bandwidth, which, if a new 404 * task wakes up imminently (starting the server again), can be used -- 405 * subject to CBS wakeup rules -- without having to wait for the next period. 406 * 407 * Additionally, because of the dl_defer behaviour the start/stop behaviour is 408 * naturally thottled to once per period, avoiding high context switch 409 * workloads from spamming the hrtimer program/cancel paths. 410 */ 411 extern void dl_server_update_idle(struct sched_dl_entity *dl_se, s64 delta_exec); 412 extern void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec); 413 extern void dl_server_start(struct sched_dl_entity *dl_se); 414 extern void dl_server_stop(struct sched_dl_entity *dl_se); 415 extern void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq, 416 dl_server_pick_f pick_task); 417 extern void sched_init_dl_servers(void); 418 419 extern void fair_server_init(struct rq *rq); 420 extern void ext_server_init(struct rq *rq); 421 extern void __dl_server_attach_root(struct sched_dl_entity *dl_se, struct rq *rq); 422 extern int dl_server_apply_params(struct sched_dl_entity *dl_se, 423 u64 runtime, u64 period, bool init); 424 425 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 u64 zero_vruntime; 688 unsigned int sum_shift; 689 690 #ifdef CONFIG_SCHED_CORE 691 unsigned int forceidle_seq; 692 u64 zero_vruntime_fi; 693 #endif 694 695 struct rb_root_cached tasks_timeline; 696 697 /* 698 * 'curr' points to the currently running entity on this cfs_rq. 699 * It is set to NULL otherwise (i.e when none are currently running). 700 */ 701 struct sched_entity *curr; 702 struct sched_entity *next; 703 704 /* 705 * CFS load tracking 706 */ 707 struct sched_avg avg; 708 #ifndef CONFIG_64BIT 709 u64 last_update_time_copy; 710 #endif 711 struct { 712 raw_spinlock_t lock ____cacheline_aligned; 713 int nr; 714 unsigned long load_avg; 715 unsigned long util_avg; 716 unsigned long runnable_avg; 717 } removed; 718 719 #ifdef CONFIG_FAIR_GROUP_SCHED 720 u64 last_update_tg_load_avg; 721 unsigned long tg_load_avg_contrib; 722 long propagate; 723 long prop_runnable_sum; 724 725 /* 726 * h_load = weight * f(tg) 727 * 728 * Where f(tg) is the recursive weight fraction assigned to 729 * this group. 730 */ 731 unsigned long h_load; 732 u64 last_h_load_update; 733 struct sched_entity *h_load_next; 734 735 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */ 736 737 /* 738 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in 739 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities 740 * (like users, containers etc.) 741 * 742 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU. 743 * This list is used during load balance. 744 */ 745 int on_list; 746 struct list_head leaf_cfs_rq_list; 747 struct task_group *tg; /* Group that "owns" this runqueue */ 748 749 /* Locally cached copy of our task_group's idle value */ 750 int idle; 751 752 # ifdef CONFIG_CFS_BANDWIDTH 753 int runtime_enabled; 754 s64 runtime_remaining; 755 756 u64 throttled_pelt_idle; 757 # ifndef CONFIG_64BIT 758 u64 throttled_pelt_idle_copy; 759 # endif 760 u64 throttled_clock; 761 u64 throttled_clock_pelt; 762 u64 throttled_clock_pelt_time; 763 u64 throttled_clock_self; 764 u64 throttled_clock_self_time; 765 bool throttled:1; 766 bool pelt_clock_throttled:1; 767 int throttle_count; 768 struct list_head throttled_list; 769 struct list_head throttled_csd_list; 770 struct list_head throttled_limbo_list; 771 # endif /* CONFIG_CFS_BANDWIDTH */ 772 #endif /* CONFIG_FAIR_GROUP_SCHED */ 773 }; 774 775 #ifdef CONFIG_SCHED_CLASS_EXT 776 /* scx_rq->flags, protected by the rq lock */ 777 enum scx_rq_flags { 778 /* 779 * A hotplugged CPU starts scheduling before rq_online_scx(). Track 780 * ops.cpu_on/offline() state so that ops.enqueue/dispatch() are called 781 * only while the BPF scheduler considers the CPU to be online. 782 */ 783 SCX_RQ_ONLINE = 1 << 0, 784 SCX_RQ_CAN_STOP_TICK = 1 << 1, 785 SCX_RQ_BAL_KEEP = 1 << 3, /* balance decided to keep current */ 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 in_select_cpu; 802 bool cpu_released; 803 u32 flags; 804 u32 nr_immed; /* ENQ_IMMED tasks on local_dsq */ 805 u64 clock; /* current per-rq clock -- see scx_bpf_now() */ 806 cpumask_var_t cpus_to_kick; 807 cpumask_var_t cpus_to_kick_if_idle; 808 cpumask_var_t cpus_to_preempt; 809 cpumask_var_t cpus_to_wait; 810 cpumask_var_t cpus_to_sync; 811 bool kick_sync_pending; 812 unsigned long kick_sync; 813 814 struct task_struct *sub_dispatch_prev; 815 816 raw_spinlock_t deferred_reenq_lock; 817 u64 deferred_reenq_locals_seq; 818 struct list_head deferred_reenq_locals; /* scheds requesting reenq of local DSQ */ 819 struct list_head deferred_reenq_users; /* user DSQs requesting reenq */ 820 struct balance_callback deferred_bal_cb; 821 struct balance_callback kick_sync_bal_cb; 822 struct irq_work deferred_irq_work; 823 struct irq_work kick_cpus_irq_work; 824 }; 825 #endif /* CONFIG_SCHED_CLASS_EXT */ 826 827 static inline int rt_bandwidth_enabled(void) 828 { 829 return sysctl_sched_rt_runtime >= 0; 830 } 831 832 /* RT IPI pull logic requires IRQ_WORK */ 833 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP) 834 # define HAVE_RT_PUSH_IPI 835 #endif 836 837 /* Real-Time classes' related field in a runqueue: */ 838 struct rt_rq { 839 struct rt_prio_array active; 840 unsigned int rt_nr_running; 841 unsigned int rr_nr_running; 842 struct { 843 int curr; /* highest queued rt task prio */ 844 int next; /* next highest */ 845 } highest_prio; 846 bool overloaded; 847 struct plist_head pushable_tasks; 848 849 int rt_queued; 850 851 #ifdef CONFIG_RT_GROUP_SCHED 852 int rt_throttled; 853 u64 rt_time; /* consumed RT time, goes up in update_curr_rt */ 854 u64 rt_runtime; /* allotted RT time, "slice" from rt_bandwidth, RT sharing/balancing */ 855 /* Nests inside the rq lock: */ 856 raw_spinlock_t rt_runtime_lock; 857 858 unsigned int rt_nr_boosted; 859 860 struct rq *rq; /* this is always top-level rq, cache? */ 861 #endif 862 #ifdef CONFIG_CGROUP_SCHED 863 struct task_group *tg; /* this tg has "this" rt_rq on given CPU for runnable entities */ 864 #endif 865 }; 866 867 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq) 868 { 869 return rt_rq->rt_queued && rt_rq->rt_nr_running; 870 } 871 872 /* Deadline class' related fields in a runqueue */ 873 struct dl_rq { 874 /* runqueue is an rbtree, ordered by deadline */ 875 struct rb_root_cached root; 876 877 unsigned int dl_nr_running; 878 879 /* 880 * Deadline values of the currently executing and the 881 * earliest ready task on this rq. Caching these facilitates 882 * the decision whether or not a ready but not running task 883 * should migrate somewhere else. 884 */ 885 struct { 886 u64 curr; 887 u64 next; 888 } earliest_dl; 889 890 bool overloaded; 891 892 /* 893 * Tasks on this rq that can be pushed away. They are kept in 894 * an rb-tree, ordered by tasks' deadlines, with caching 895 * of the leftmost (earliest deadline) element. 896 */ 897 struct rb_root_cached pushable_dl_tasks_root; 898 899 /* 900 * "Active utilization" for this runqueue: increased when a 901 * task wakes up (becomes TASK_RUNNING) and decreased when a 902 * task blocks 903 */ 904 u64 running_bw; 905 906 /* 907 * Utilization of the tasks "assigned" to this runqueue (including 908 * the tasks that are in runqueue and the tasks that executed on this 909 * CPU and blocked). Increased when a task moves to this runqueue, and 910 * decreased when the task moves away (migrates, changes scheduling 911 * policy, or terminates). 912 * This is needed to compute the "inactive utilization" for the 913 * runqueue (inactive utilization = this_bw - running_bw). 914 */ 915 u64 this_bw; 916 u64 extra_bw; 917 918 /* 919 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM 920 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB). 921 */ 922 u64 max_bw; 923 924 /* 925 * Inverse of the fraction of CPU utilization that can be reclaimed 926 * by the GRUB algorithm. 927 */ 928 u64 bw_ratio; 929 }; 930 931 #ifdef CONFIG_FAIR_GROUP_SCHED 932 933 /* An entity is a task if it doesn't "own" a runqueue */ 934 #define entity_is_task(se) (!se->my_q) 935 936 static inline void se_update_runnable(struct sched_entity *se) 937 { 938 if (!entity_is_task(se)) 939 se->runnable_weight = se->my_q->h_nr_runnable; 940 } 941 942 static inline long se_runnable(struct sched_entity *se) 943 { 944 if (se->sched_delayed) 945 return false; 946 947 if (entity_is_task(se)) 948 return !!se->on_rq; 949 else 950 return se->runnable_weight; 951 } 952 953 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 954 955 #define entity_is_task(se) 1 956 957 static inline void se_update_runnable(struct sched_entity *se) { } 958 959 static inline long se_runnable(struct sched_entity *se) 960 { 961 if (se->sched_delayed) 962 return false; 963 964 return !!se->on_rq; 965 } 966 967 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 968 969 /* 970 * XXX we want to get rid of these helpers and use the full load resolution. 971 */ 972 static inline long se_weight(struct sched_entity *se) 973 { 974 return scale_load_down(se->load.weight); 975 } 976 977 978 static inline bool sched_asym_prefer(int a, int b) 979 { 980 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b); 981 } 982 983 struct perf_domain { 984 struct em_perf_domain *em_pd; 985 struct perf_domain *next; 986 struct rcu_head rcu; 987 }; 988 989 /* 990 * We add the notion of a root-domain which will be used to define per-domain 991 * variables. Each exclusive cpuset essentially defines an island domain by 992 * fully partitioning the member CPUs from any other cpuset. Whenever a new 993 * exclusive cpuset is created, we also create and attach a new root-domain 994 * object. 995 * 996 */ 997 struct root_domain { 998 atomic_t refcount; 999 atomic_t rto_count; 1000 struct rcu_head rcu; 1001 cpumask_var_t span; 1002 cpumask_var_t online; 1003 1004 /* 1005 * Indicate pullable load on at least one CPU, e.g: 1006 * - More than one runnable task 1007 * - Running task is misfit 1008 */ 1009 bool overloaded; 1010 1011 /* Indicate one or more CPUs over-utilized (tipping point) */ 1012 bool overutilized; 1013 1014 /* 1015 * The bit corresponding to a CPU gets set here if such CPU has more 1016 * than one runnable -deadline task (as it is below for RT tasks). 1017 */ 1018 cpumask_var_t dlo_mask; 1019 atomic_t dlo_count; 1020 struct dl_bw dl_bw; 1021 struct cpudl cpudl; 1022 1023 /* 1024 * Indicate whether a root_domain's dl_bw has been checked or 1025 * updated. It's monotonously increasing value. 1026 * 1027 * Also, some corner cases, like 'wrap around' is dangerous, but given 1028 * that u64 is 'big enough'. So that shouldn't be a concern. 1029 */ 1030 u64 visit_cookie; 1031 1032 #ifdef HAVE_RT_PUSH_IPI 1033 /* 1034 * For IPI pull requests, loop across the rto_mask. 1035 */ 1036 struct irq_work rto_push_work; 1037 raw_spinlock_t rto_lock; 1038 /* These are only updated and read within rto_lock */ 1039 int rto_loop; 1040 int rto_cpu; 1041 /* These atomics are updated outside of a lock */ 1042 atomic_t rto_loop_next; 1043 atomic_t rto_loop_start; 1044 #endif /* HAVE_RT_PUSH_IPI */ 1045 /* 1046 * The "RT overload" flag: it gets set if a CPU has more than 1047 * one runnable RT task. 1048 */ 1049 cpumask_var_t rto_mask; 1050 struct cpupri cpupri; 1051 1052 /* 1053 * NULL-terminated list of performance domains intersecting with the 1054 * CPUs of the rd. Protected by RCU. 1055 */ 1056 struct perf_domain __rcu *pd; 1057 }; 1058 1059 extern void init_defrootdomain(void); 1060 extern int sched_init_domains(const struct cpumask *cpu_map); 1061 extern void rq_attach_root(struct rq *rq, struct root_domain *rd); 1062 extern void sched_get_rd(struct root_domain *rd); 1063 extern void sched_put_rd(struct root_domain *rd); 1064 1065 static inline int get_rd_overloaded(struct root_domain *rd) 1066 { 1067 return READ_ONCE(rd->overloaded); 1068 } 1069 1070 static inline void set_rd_overloaded(struct root_domain *rd, int status) 1071 { 1072 if (get_rd_overloaded(rd) != status) 1073 WRITE_ONCE(rd->overloaded, status); 1074 } 1075 1076 #ifdef HAVE_RT_PUSH_IPI 1077 extern void rto_push_irq_work_func(struct irq_work *work); 1078 #endif 1079 1080 #ifdef CONFIG_UCLAMP_TASK 1081 /* 1082 * struct uclamp_bucket - Utilization clamp bucket 1083 * @value: utilization clamp value for tasks on this clamp bucket 1084 * @tasks: number of RUNNABLE tasks on this clamp bucket 1085 * 1086 * Keep track of how many tasks are RUNNABLE for a given utilization 1087 * clamp value. 1088 */ 1089 struct uclamp_bucket { 1090 unsigned long value : bits_per(SCHED_CAPACITY_SCALE); 1091 unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE); 1092 }; 1093 1094 /* 1095 * struct uclamp_rq - rq's utilization clamp 1096 * @value: currently active clamp values for a rq 1097 * @bucket: utilization clamp buckets affecting a rq 1098 * 1099 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values. 1100 * A clamp value is affecting a rq when there is at least one task RUNNABLE 1101 * (or actually running) with that value. 1102 * 1103 * There are up to UCLAMP_CNT possible different clamp values, currently there 1104 * are only two: minimum utilization and maximum utilization. 1105 * 1106 * All utilization clamping values are MAX aggregated, since: 1107 * - for util_min: we want to run the CPU at least at the max of the minimum 1108 * utilization required by its currently RUNNABLE tasks. 1109 * - for util_max: we want to allow the CPU to run up to the max of the 1110 * maximum utilization allowed by its currently RUNNABLE tasks. 1111 * 1112 * Since on each system we expect only a limited number of different 1113 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track 1114 * the metrics required to compute all the per-rq utilization clamp values. 1115 */ 1116 struct uclamp_rq { 1117 unsigned int value; 1118 struct uclamp_bucket bucket[UCLAMP_BUCKETS]; 1119 }; 1120 1121 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used); 1122 #endif /* CONFIG_UCLAMP_TASK */ 1123 1124 /* 1125 * This is the main, per-CPU runqueue data structure. 1126 * 1127 * Locking rule: those places that want to lock multiple runqueues 1128 * (such as the load balancing or the thread migration code), lock 1129 * acquire operations must be ordered by ascending &runqueue. 1130 */ 1131 struct rq { 1132 /* 1133 * The following members are loaded together, without holding the 1134 * rq->lock, in an extremely hot loop in update_sg_lb_stats() 1135 * (called from pick_next_task()). To reduce cache pollution from 1136 * this operation, they are placed together on this dedicated cache 1137 * line. Even though some of them are frequently modified, they are 1138 * loaded much more frequently than they are stored. 1139 */ 1140 unsigned int nr_running; 1141 #ifdef CONFIG_NUMA_BALANCING 1142 unsigned int nr_numa_running; 1143 unsigned int nr_preferred_running; 1144 #endif 1145 unsigned int ttwu_pending; 1146 unsigned long cpu_capacity; 1147 #ifdef CONFIG_SCHED_PROXY_EXEC 1148 struct task_struct __rcu *donor; /* Scheduling context */ 1149 struct task_struct __rcu *curr; /* Execution context */ 1150 #else 1151 union { 1152 struct task_struct __rcu *donor; /* Scheduler context */ 1153 struct task_struct __rcu *curr; /* Execution context */ 1154 }; 1155 #endif 1156 struct task_struct *idle; 1157 /* padding left here deliberately */ 1158 1159 /* 1160 * The next cacheline holds the (hot) runqueue lock, as well as 1161 * some other less performance-critical fields. 1162 */ 1163 u64 nr_switches ____cacheline_aligned; 1164 1165 /* runqueue lock: */ 1166 raw_spinlock_t __lock; 1167 1168 #ifdef CONFIG_NO_HZ_COMMON 1169 unsigned int nohz_tick_stopped; 1170 atomic_t nohz_flags; 1171 unsigned int has_blocked_load; 1172 unsigned long last_blocked_load_update_tick; 1173 call_single_data_t nohz_csd; 1174 #endif /* CONFIG_NO_HZ_COMMON */ 1175 1176 #ifdef CONFIG_UCLAMP_TASK 1177 /* Utilization clamp values based on CPU's RUNNABLE tasks */ 1178 struct uclamp_rq uclamp[UCLAMP_CNT] ____cacheline_aligned; 1179 unsigned int uclamp_flags; 1180 #define UCLAMP_FLAG_IDLE 0x01 1181 #endif 1182 1183 struct cfs_rq cfs; 1184 struct rt_rq rt; 1185 struct dl_rq dl; 1186 #ifdef CONFIG_SCHED_CLASS_EXT 1187 struct scx_rq scx; 1188 struct sched_dl_entity ext_server; 1189 #endif 1190 1191 struct sched_dl_entity fair_server; 1192 1193 #ifdef CONFIG_FAIR_GROUP_SCHED 1194 /* list of leaf cfs_rq on this CPU: */ 1195 struct list_head leaf_cfs_rq_list; 1196 struct list_head *tmp_alone_branch; 1197 #endif /* CONFIG_FAIR_GROUP_SCHED */ 1198 1199 #ifdef CONFIG_NUMA_BALANCING 1200 unsigned int numa_migrate_on; 1201 #endif 1202 /* 1203 * This is part of a global counter where only the total sum 1204 * over all CPUs matters. A task can increase this counter on 1205 * one CPU and if it got migrated afterwards it may decrease 1206 * it on another CPU. Always updated under the runqueue lock: 1207 */ 1208 unsigned long nr_uninterruptible; 1209 1210 struct sched_dl_entity *dl_server; 1211 struct task_struct *stop; 1212 const struct sched_class *next_class; 1213 unsigned long next_balance; 1214 struct mm_struct *prev_mm; 1215 1216 /* 1217 * The following fields of clock data are frequently referenced 1218 * and updated together, and should go on their own cache line. 1219 */ 1220 u64 clock_task ____cacheline_aligned; 1221 u64 clock_pelt; 1222 u64 clock; 1223 unsigned long lost_idle_time; 1224 unsigned int clock_update_flags; 1225 u64 clock_pelt_idle; 1226 u64 clock_idle; 1227 1228 #ifndef CONFIG_64BIT 1229 u64 clock_pelt_idle_copy; 1230 u64 clock_idle_copy; 1231 #endif 1232 1233 u64 last_seen_need_resched_ns; 1234 int ticks_without_resched; 1235 1236 #ifdef CONFIG_MEMBARRIER 1237 int membarrier_state; 1238 #endif 1239 1240 struct root_domain *rd; 1241 struct sched_domain __rcu *sd; 1242 1243 struct balance_callback *balance_callback; 1244 1245 unsigned char nohz_idle_balance; 1246 unsigned char idle_balance; 1247 1248 unsigned long misfit_task_load; 1249 1250 /* For active balancing */ 1251 int active_balance; 1252 int push_cpu; 1253 struct cpu_stop_work active_balance_work; 1254 1255 /* CPU of this runqueue: */ 1256 int cpu; 1257 int online; 1258 1259 struct list_head cfs_tasks; 1260 1261 struct sched_avg avg_rt; 1262 struct sched_avg avg_dl; 1263 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 1264 struct sched_avg avg_irq; 1265 #endif 1266 #ifdef CONFIG_SCHED_HW_PRESSURE 1267 struct sched_avg avg_hw; 1268 #endif 1269 u64 idle_stamp; 1270 u64 avg_idle; 1271 1272 /* This is used to determine avg_idle's max value */ 1273 u64 max_idle_balance_cost; 1274 1275 #ifdef CONFIG_HOTPLUG_CPU 1276 struct rcuwait hotplug_wait; 1277 #endif 1278 1279 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 1280 u64 prev_irq_time; 1281 u64 psi_irq_time; 1282 #endif 1283 #ifdef CONFIG_PARAVIRT 1284 u64 prev_steal_time; 1285 #endif 1286 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING 1287 u64 prev_steal_time_rq; 1288 #endif 1289 1290 /* calc_load related fields */ 1291 unsigned long calc_load_update; 1292 long calc_load_active; 1293 1294 #ifdef CONFIG_SCHED_HRTICK 1295 call_single_data_t hrtick_csd; 1296 struct hrtimer hrtick_timer; 1297 ktime_t hrtick_time; 1298 ktime_t hrtick_delay; 1299 unsigned int hrtick_sched; 1300 #endif 1301 1302 #ifdef CONFIG_SCHEDSTATS 1303 /* latency stats */ 1304 struct sched_info rq_sched_info; 1305 unsigned long long rq_cpu_time; 1306 1307 /* sys_sched_yield() stats */ 1308 unsigned int yld_count; 1309 1310 /* schedule() stats */ 1311 unsigned int sched_count; 1312 unsigned int sched_goidle; 1313 1314 /* try_to_wake_up() stats */ 1315 unsigned int ttwu_count; 1316 unsigned int ttwu_local; 1317 #endif 1318 1319 #ifdef CONFIG_CPU_IDLE 1320 /* Must be inspected within a RCU lock section */ 1321 struct cpuidle_state *idle_state; 1322 #endif 1323 1324 unsigned int nr_pinned; 1325 unsigned int push_busy; 1326 struct cpu_stop_work push_work; 1327 1328 #ifdef CONFIG_SCHED_CORE 1329 /* per rq */ 1330 struct rq *core; 1331 struct task_struct *core_pick; 1332 struct sched_dl_entity *core_dl_server; 1333 unsigned int core_enabled; 1334 unsigned int core_sched_seq; 1335 struct rb_root core_tree; 1336 1337 /* shared state -- careful with sched_core_cpu_deactivate() */ 1338 unsigned int core_task_seq; 1339 unsigned int core_pick_seq; 1340 unsigned long core_cookie; 1341 unsigned int core_forceidle_count; 1342 unsigned int core_forceidle_seq; 1343 unsigned int core_forceidle_occupation; 1344 u64 core_forceidle_start; 1345 #endif /* CONFIG_SCHED_CORE */ 1346 1347 /* Scratch cpumask to be temporarily used under rq_lock */ 1348 cpumask_var_t scratch_mask; 1349 1350 #ifdef CONFIG_CFS_BANDWIDTH 1351 call_single_data_t cfsb_csd; 1352 struct list_head cfsb_csd_list; 1353 #endif 1354 1355 atomic_t nr_iowait; 1356 } __no_randomize_layout; 1357 1358 #ifdef CONFIG_FAIR_GROUP_SCHED 1359 1360 /* CPU runqueue to which this cfs_rq is attached */ 1361 static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1362 { 1363 return cfs_rq->rq; 1364 } 1365 1366 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 1367 1368 static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1369 { 1370 return container_of(cfs_rq, struct rq, cfs); 1371 } 1372 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 1373 1374 static inline int cpu_of(struct rq *rq) 1375 { 1376 return rq->cpu; 1377 } 1378 1379 #define MDF_PUSH 0x01 1380 1381 static inline bool is_migration_disabled(struct task_struct *p) 1382 { 1383 return p->migration_disabled; 1384 } 1385 1386 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); 1387 DECLARE_PER_CPU(struct rnd_state, sched_rnd_state); 1388 1389 static inline u32 sched_rng(void) 1390 { 1391 return prandom_u32_state(this_cpu_ptr(&sched_rnd_state)); 1392 } 1393 1394 static __always_inline struct rq *__this_rq(void) 1395 { 1396 return this_cpu_ptr(&runqueues); 1397 } 1398 1399 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) 1400 #define this_rq() __this_rq() 1401 #define task_rq(p) cpu_rq(task_cpu(p)) 1402 #define cpu_curr(cpu) (cpu_rq(cpu)->curr) 1403 #define raw_rq() raw_cpu_ptr(&runqueues) 1404 1405 static inline bool idle_rq(struct rq *rq) 1406 { 1407 return rq->curr == rq->idle && !rq->nr_running && !rq->ttwu_pending; 1408 } 1409 1410 /** 1411 * available_idle_cpu - is a given CPU idle for enqueuing work. 1412 * @cpu: the CPU in question. 1413 * 1414 * Return: 1 if the CPU is currently idle. 0 otherwise. 1415 */ 1416 static inline bool available_idle_cpu(int cpu) 1417 { 1418 if (!idle_rq(cpu_rq(cpu))) 1419 return 0; 1420 1421 if (vcpu_is_preempted(cpu)) 1422 return 0; 1423 1424 return 1; 1425 } 1426 1427 #ifdef CONFIG_SCHED_PROXY_EXEC 1428 static inline void rq_set_donor(struct rq *rq, struct task_struct *t) 1429 { 1430 rcu_assign_pointer(rq->donor, t); 1431 } 1432 #else 1433 static inline void rq_set_donor(struct rq *rq, struct task_struct *t) 1434 { 1435 /* Do nothing */ 1436 } 1437 #endif 1438 1439 #ifdef CONFIG_SCHED_CORE 1440 static inline struct cpumask *sched_group_span(struct sched_group *sg); 1441 1442 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled); 1443 1444 static inline bool sched_core_enabled(struct rq *rq) 1445 { 1446 return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled; 1447 } 1448 1449 static inline bool sched_core_disabled(void) 1450 { 1451 return !static_branch_unlikely(&__sched_core_enabled); 1452 } 1453 1454 /* 1455 * Be careful with this function; not for general use. The return value isn't 1456 * stable unless you actually hold a relevant rq->__lock. 1457 */ 1458 static inline raw_spinlock_t *rq_lockp(struct rq *rq) 1459 { 1460 if (sched_core_enabled(rq)) 1461 return &rq->core->__lock; 1462 1463 return &rq->__lock; 1464 } 1465 1466 static inline raw_spinlock_t *__rq_lockp(struct rq *rq) 1467 __returns_ctx_lock(rq_lockp(rq)) /* alias them */ 1468 { 1469 if (rq->core_enabled) 1470 return &rq->core->__lock; 1471 1472 return &rq->__lock; 1473 } 1474 1475 extern bool 1476 cfs_prio_less(const struct task_struct *a, const struct task_struct *b, bool fi); 1477 1478 extern void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi); 1479 1480 /* 1481 * Helpers to check if the CPU's core cookie matches with the task's cookie 1482 * when core scheduling is enabled. 1483 * A special case is that the task's cookie always matches with CPU's core 1484 * cookie if the CPU is in an idle core. 1485 */ 1486 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p) 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 return rq->core->core_cookie == p->core_cookie; 1493 } 1494 1495 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) 1496 { 1497 bool idle_core = true; 1498 int cpu; 1499 1500 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1501 if (!sched_core_enabled(rq)) 1502 return true; 1503 1504 if (rq->core->core_cookie == p->core_cookie) 1505 return true; 1506 1507 for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) { 1508 if (!available_idle_cpu(cpu)) { 1509 idle_core = false; 1510 break; 1511 } 1512 } 1513 1514 /* 1515 * A CPU in an idle core is always the best choice for tasks with 1516 * cookies. 1517 */ 1518 return idle_core; 1519 } 1520 1521 static inline bool sched_group_cookie_match(struct rq *rq, 1522 struct task_struct *p, 1523 struct sched_group *group) 1524 { 1525 int cpu; 1526 1527 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1528 if (!sched_core_enabled(rq)) 1529 return true; 1530 1531 for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) { 1532 if (sched_core_cookie_match(cpu_rq(cpu), p)) 1533 return true; 1534 } 1535 return false; 1536 } 1537 1538 static inline bool sched_core_enqueued(struct task_struct *p) 1539 { 1540 return !RB_EMPTY_NODE(&p->core_node); 1541 } 1542 1543 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p); 1544 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags); 1545 1546 extern void sched_core_get(void); 1547 extern void sched_core_put(void); 1548 1549 #else /* !CONFIG_SCHED_CORE: */ 1550 1551 static inline bool sched_core_enabled(struct rq *rq) 1552 { 1553 return false; 1554 } 1555 1556 static inline bool sched_core_disabled(void) 1557 { 1558 return true; 1559 } 1560 1561 static inline raw_spinlock_t *rq_lockp(struct rq *rq) 1562 { 1563 return &rq->__lock; 1564 } 1565 1566 static inline raw_spinlock_t *__rq_lockp(struct rq *rq) 1567 __returns_ctx_lock(rq_lockp(rq)) /* alias them */ 1568 { 1569 return &rq->__lock; 1570 } 1571 1572 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p) 1573 { 1574 return true; 1575 } 1576 1577 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) 1578 { 1579 return true; 1580 } 1581 1582 static inline bool sched_group_cookie_match(struct rq *rq, 1583 struct task_struct *p, 1584 struct sched_group *group) 1585 { 1586 return true; 1587 } 1588 1589 #endif /* !CONFIG_SCHED_CORE */ 1590 1591 #ifdef CONFIG_RT_GROUP_SCHED 1592 # ifdef CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED 1593 DECLARE_STATIC_KEY_FALSE(rt_group_sched); 1594 static inline bool rt_group_sched_enabled(void) 1595 { 1596 return static_branch_unlikely(&rt_group_sched); 1597 } 1598 # else /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED: */ 1599 DECLARE_STATIC_KEY_TRUE(rt_group_sched); 1600 static inline bool rt_group_sched_enabled(void) 1601 { 1602 return static_branch_likely(&rt_group_sched); 1603 } 1604 # endif /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED */ 1605 #else /* !CONFIG_RT_GROUP_SCHED: */ 1606 # define rt_group_sched_enabled() false 1607 #endif /* !CONFIG_RT_GROUP_SCHED */ 1608 1609 static inline void lockdep_assert_rq_held(struct rq *rq) 1610 __assumes_ctx_lock(__rq_lockp(rq)) 1611 { 1612 lockdep_assert_held(__rq_lockp(rq)); 1613 } 1614 1615 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass) 1616 __acquires(__rq_lockp(rq)); 1617 1618 extern bool raw_spin_rq_trylock(struct rq *rq) 1619 __cond_acquires(true, __rq_lockp(rq)); 1620 1621 static inline void raw_spin_rq_lock(struct rq *rq) 1622 __acquires(__rq_lockp(rq)) 1623 { 1624 raw_spin_rq_lock_nested(rq, 0); 1625 } 1626 1627 static inline void raw_spin_rq_unlock(struct rq *rq) 1628 __releases(__rq_lockp(rq)) 1629 { 1630 raw_spin_unlock(rq_lockp(rq)); 1631 } 1632 1633 static inline void raw_spin_rq_lock_irq(struct rq *rq) 1634 __acquires(__rq_lockp(rq)) 1635 { 1636 local_irq_disable(); 1637 raw_spin_rq_lock(rq); 1638 } 1639 1640 static inline void raw_spin_rq_unlock_irq(struct rq *rq) 1641 __releases(__rq_lockp(rq)) 1642 { 1643 raw_spin_rq_unlock(rq); 1644 local_irq_enable(); 1645 } 1646 1647 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq) 1648 __acquires(__rq_lockp(rq)) 1649 { 1650 unsigned long flags; 1651 1652 local_irq_save(flags); 1653 raw_spin_rq_lock(rq); 1654 1655 return flags; 1656 } 1657 1658 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags) 1659 __releases(__rq_lockp(rq)) 1660 { 1661 raw_spin_rq_unlock(rq); 1662 local_irq_restore(flags); 1663 } 1664 1665 #define raw_spin_rq_lock_irqsave(rq, flags) \ 1666 do { \ 1667 flags = _raw_spin_rq_lock_irqsave(rq); \ 1668 } while (0) 1669 1670 #ifdef CONFIG_SCHED_SMT 1671 extern void __update_idle_core(struct rq *rq); 1672 1673 static inline void update_idle_core(struct rq *rq) 1674 { 1675 if (static_branch_unlikely(&sched_smt_present)) 1676 __update_idle_core(rq); 1677 } 1678 1679 #else /* !CONFIG_SCHED_SMT: */ 1680 static inline void update_idle_core(struct rq *rq) { } 1681 #endif /* !CONFIG_SCHED_SMT */ 1682 1683 #ifdef CONFIG_FAIR_GROUP_SCHED 1684 1685 static inline struct task_struct *task_of(struct sched_entity *se) 1686 { 1687 WARN_ON_ONCE(!entity_is_task(se)); 1688 return container_of(se, struct task_struct, se); 1689 } 1690 1691 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p) 1692 { 1693 return p->se.cfs_rq; 1694 } 1695 1696 /* runqueue on which this entity is (to be) queued */ 1697 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se) 1698 { 1699 return se->cfs_rq; 1700 } 1701 1702 /* runqueue "owned" by this group */ 1703 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) 1704 { 1705 return grp->my_q; 1706 } 1707 1708 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 1709 1710 #define task_of(_se) container_of(_se, struct task_struct, se) 1711 1712 static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p) 1713 { 1714 return &task_rq(p)->cfs; 1715 } 1716 1717 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se) 1718 { 1719 const struct task_struct *p = task_of(se); 1720 struct rq *rq = task_rq(p); 1721 1722 return &rq->cfs; 1723 } 1724 1725 /* runqueue "owned" by this group */ 1726 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) 1727 { 1728 return NULL; 1729 } 1730 1731 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 1732 1733 extern void update_rq_avg_idle(struct rq *rq); 1734 extern void update_rq_clock(struct rq *rq); 1735 1736 /* 1737 * rq::clock_update_flags bits 1738 * 1739 * %RQCF_REQ_SKIP - will request skipping of clock update on the next 1740 * call to __schedule(). This is an optimisation to avoid 1741 * neighbouring rq clock updates. 1742 * 1743 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is 1744 * in effect and calls to update_rq_clock() are being ignored. 1745 * 1746 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been 1747 * made to update_rq_clock() since the last time rq::lock was pinned. 1748 * 1749 * If inside of __schedule(), clock_update_flags will have been 1750 * shifted left (a left shift is a cheap operation for the fast path 1751 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use, 1752 * 1753 * if (rq-clock_update_flags >= RQCF_UPDATED) 1754 * 1755 * to check if %RQCF_UPDATED is set. It'll never be shifted more than 1756 * one position though, because the next rq_unpin_lock() will shift it 1757 * back. 1758 */ 1759 #define RQCF_REQ_SKIP 0x01 1760 #define RQCF_ACT_SKIP 0x02 1761 #define RQCF_UPDATED 0x04 1762 1763 static inline void assert_clock_updated(struct rq *rq) 1764 { 1765 /* 1766 * The only reason for not seeing a clock update since the 1767 * last rq_pin_lock() is if we're currently skipping updates. 1768 */ 1769 WARN_ON_ONCE(rq->clock_update_flags < RQCF_ACT_SKIP); 1770 } 1771 1772 static inline u64 rq_clock(struct rq *rq) 1773 { 1774 lockdep_assert_rq_held(rq); 1775 assert_clock_updated(rq); 1776 1777 return rq->clock; 1778 } 1779 1780 static inline u64 rq_clock_task(struct rq *rq) 1781 { 1782 lockdep_assert_rq_held(rq); 1783 assert_clock_updated(rq); 1784 1785 return rq->clock_task; 1786 } 1787 1788 static inline void rq_clock_skip_update(struct rq *rq) 1789 { 1790 lockdep_assert_rq_held(rq); 1791 rq->clock_update_flags |= RQCF_REQ_SKIP; 1792 } 1793 1794 /* 1795 * See rt task throttling, which is the only time a skip 1796 * request is canceled. 1797 */ 1798 static inline void rq_clock_cancel_skipupdate(struct rq *rq) 1799 { 1800 lockdep_assert_rq_held(rq); 1801 rq->clock_update_flags &= ~RQCF_REQ_SKIP; 1802 } 1803 1804 /* 1805 * During cpu offlining and rq wide unthrottling, we can trigger 1806 * an update_rq_clock() for several cfs and rt runqueues (Typically 1807 * when using list_for_each_entry_*) 1808 * rq_clock_start_loop_update() can be called after updating the clock 1809 * once and before iterating over the list to prevent multiple update. 1810 * After the iterative traversal, we need to call rq_clock_stop_loop_update() 1811 * to clear RQCF_ACT_SKIP of rq->clock_update_flags. 1812 */ 1813 static inline void rq_clock_start_loop_update(struct rq *rq) 1814 { 1815 lockdep_assert_rq_held(rq); 1816 WARN_ON_ONCE(rq->clock_update_flags & RQCF_ACT_SKIP); 1817 rq->clock_update_flags |= RQCF_ACT_SKIP; 1818 } 1819 1820 static inline void rq_clock_stop_loop_update(struct rq *rq) 1821 { 1822 lockdep_assert_rq_held(rq); 1823 rq->clock_update_flags &= ~RQCF_ACT_SKIP; 1824 } 1825 1826 struct rq_flags { 1827 unsigned long flags; 1828 struct pin_cookie cookie; 1829 /* 1830 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the 1831 * current pin context is stashed here in case it needs to be 1832 * restored in rq_repin_lock(). 1833 */ 1834 unsigned int clock_update_flags; 1835 }; 1836 1837 extern struct balance_callback balance_push_callback; 1838 1839 #ifdef CONFIG_SCHED_CLASS_EXT 1840 extern const struct sched_class ext_sched_class; 1841 1842 DECLARE_STATIC_KEY_FALSE(__scx_enabled); /* SCX BPF scheduler loaded */ 1843 DECLARE_STATIC_KEY_FALSE(__scx_switched_all); /* all fair class tasks on SCX */ 1844 1845 #define scx_enabled() static_branch_unlikely(&__scx_enabled) 1846 #define scx_switched_all() static_branch_unlikely(&__scx_switched_all) 1847 1848 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) 1849 { 1850 if (!scx_enabled()) 1851 return; 1852 WRITE_ONCE(rq->scx.clock, clock); 1853 smp_store_release(&rq->scx.flags, rq->scx.flags | SCX_RQ_CLK_VALID); 1854 } 1855 1856 static inline void scx_rq_clock_invalidate(struct rq *rq) 1857 { 1858 if (!scx_enabled()) 1859 return; 1860 WRITE_ONCE(rq->scx.flags, rq->scx.flags & ~SCX_RQ_CLK_VALID); 1861 } 1862 1863 #else /* !CONFIG_SCHED_CLASS_EXT: */ 1864 #define scx_enabled() false 1865 #define scx_switched_all() false 1866 1867 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) {} 1868 static inline void scx_rq_clock_invalidate(struct rq *rq) {} 1869 #endif /* !CONFIG_SCHED_CLASS_EXT */ 1870 1871 static inline void assert_balance_callbacks_empty(struct rq *rq) 1872 { 1873 WARN_ON_ONCE(IS_ENABLED(CONFIG_PROVE_LOCKING) && 1874 rq->balance_callback && 1875 rq->balance_callback != &balance_push_callback); 1876 } 1877 1878 /* 1879 * Lockdep annotation that avoids accidental unlocks; it's like a 1880 * sticky/continuous lockdep_assert_held(). 1881 * 1882 * This avoids code that has access to 'struct rq *rq' (basically everything in 1883 * the scheduler) from accidentally unlocking the rq if they do not also have a 1884 * copy of the (on-stack) 'struct rq_flags rf'. 1885 * 1886 * Also see Documentation/locking/lockdep-design.rst. 1887 */ 1888 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf) 1889 { 1890 rf->cookie = lockdep_pin_lock(__rq_lockp(rq)); 1891 1892 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 1893 rf->clock_update_flags = 0; 1894 assert_balance_callbacks_empty(rq); 1895 } 1896 1897 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf) 1898 { 1899 if (rq->clock_update_flags > RQCF_ACT_SKIP) 1900 rf->clock_update_flags = RQCF_UPDATED; 1901 1902 scx_rq_clock_invalidate(rq); 1903 lockdep_unpin_lock(__rq_lockp(rq), rf->cookie); 1904 } 1905 1906 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf) 1907 { 1908 lockdep_repin_lock(__rq_lockp(rq), rf->cookie); 1909 1910 /* 1911 * Restore the value we stashed in @rf for this pin context. 1912 */ 1913 rq->clock_update_flags |= rf->clock_update_flags; 1914 } 1915 1916 #define __task_rq_lock(...) __acquire_ret(___task_rq_lock(__VA_ARGS__), __rq_lockp(__ret)) 1917 extern struct rq *___task_rq_lock(struct task_struct *p, struct rq_flags *rf) __acquires_ret; 1918 1919 #define task_rq_lock(...) __acquire_ret(_task_rq_lock(__VA_ARGS__), __rq_lockp(__ret)) 1920 extern struct rq *_task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1921 __acquires(&p->pi_lock) __acquires_ret; 1922 1923 static inline void 1924 __task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) 1925 __releases(__rq_lockp(rq)) 1926 { 1927 rq_unpin_lock(rq, rf); 1928 raw_spin_rq_unlock(rq); 1929 } 1930 1931 static inline void 1932 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) 1933 __releases(__rq_lockp(rq), &p->pi_lock) 1934 { 1935 __task_rq_unlock(rq, p, rf); 1936 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); 1937 } 1938 1939 DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct, 1940 _T->rq = task_rq_lock(_T->lock, &_T->rf), 1941 task_rq_unlock(_T->rq, _T->lock, &_T->rf), 1942 struct rq *rq; struct rq_flags rf) 1943 DECLARE_LOCK_GUARD_1_ATTRS(task_rq_lock, __acquires(_T->pi_lock), __releases((*(struct task_struct **)_T)->pi_lock)) 1944 #define class_task_rq_lock_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(task_rq_lock, _T) 1945 1946 DEFINE_LOCK_GUARD_1(__task_rq_lock, struct task_struct, 1947 _T->rq = __task_rq_lock(_T->lock, &_T->rf), 1948 __task_rq_unlock(_T->rq, _T->lock, &_T->rf), 1949 struct rq *rq; struct rq_flags rf) 1950 1951 static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) 1952 __acquires(__rq_lockp(rq)) 1953 { 1954 raw_spin_rq_lock_irqsave(rq, rf->flags); 1955 rq_pin_lock(rq, rf); 1956 } 1957 1958 static inline void rq_lock_irq(struct rq *rq, struct rq_flags *rf) 1959 __acquires(__rq_lockp(rq)) 1960 { 1961 raw_spin_rq_lock_irq(rq); 1962 rq_pin_lock(rq, rf); 1963 } 1964 1965 static inline void rq_lock(struct rq *rq, struct rq_flags *rf) 1966 __acquires(__rq_lockp(rq)) 1967 { 1968 raw_spin_rq_lock(rq); 1969 rq_pin_lock(rq, rf); 1970 } 1971 1972 static inline void rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf) 1973 __releases(__rq_lockp(rq)) 1974 { 1975 rq_unpin_lock(rq, rf); 1976 raw_spin_rq_unlock_irqrestore(rq, rf->flags); 1977 } 1978 1979 static inline void rq_unlock_irq(struct rq *rq, struct rq_flags *rf) 1980 __releases(__rq_lockp(rq)) 1981 { 1982 rq_unpin_lock(rq, rf); 1983 raw_spin_rq_unlock_irq(rq); 1984 } 1985 1986 static inline void rq_unlock(struct rq *rq, struct rq_flags *rf) 1987 __releases(__rq_lockp(rq)) 1988 { 1989 rq_unpin_lock(rq, rf); 1990 raw_spin_rq_unlock(rq); 1991 } 1992 1993 DEFINE_LOCK_GUARD_1(rq_lock, struct rq, 1994 rq_lock(_T->lock, &_T->rf), 1995 rq_unlock(_T->lock, &_T->rf), 1996 struct rq_flags rf) 1997 1998 DECLARE_LOCK_GUARD_1_ATTRS(rq_lock, __acquires(__rq_lockp(_T)), __releases(__rq_lockp(*(struct rq **)_T))); 1999 #define class_rq_lock_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock, _T) 2000 2001 DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq, 2002 rq_lock_irq(_T->lock, &_T->rf), 2003 rq_unlock_irq(_T->lock, &_T->rf), 2004 struct rq_flags rf) 2005 2006 DECLARE_LOCK_GUARD_1_ATTRS(rq_lock_irq, __acquires(__rq_lockp(_T)), __releases(__rq_lockp(*(struct rq **)_T))); 2007 #define class_rq_lock_irq_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock_irq, _T) 2008 2009 DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq, 2010 rq_lock_irqsave(_T->lock, &_T->rf), 2011 rq_unlock_irqrestore(_T->lock, &_T->rf), 2012 struct rq_flags rf) 2013 2014 DECLARE_LOCK_GUARD_1_ATTRS(rq_lock_irqsave, __acquires(__rq_lockp(_T)), __releases(__rq_lockp(*(struct rq **)_T))); 2015 #define class_rq_lock_irqsave_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock_irqsave, _T) 2016 2017 #define this_rq_lock_irq(...) __acquire_ret(_this_rq_lock_irq(__VA_ARGS__), __rq_lockp(__ret)) 2018 static inline struct rq *_this_rq_lock_irq(struct rq_flags *rf) __acquires_ret 2019 { 2020 struct rq *rq; 2021 2022 local_irq_disable(); 2023 rq = this_rq(); 2024 rq_lock(rq, rf); 2025 2026 return rq; 2027 } 2028 2029 #ifdef CONFIG_NUMA 2030 2031 enum numa_topology_type { 2032 NUMA_DIRECT, 2033 NUMA_GLUELESS_MESH, 2034 NUMA_BACKPLANE, 2035 }; 2036 2037 extern enum numa_topology_type sched_numa_topology_type; 2038 extern int sched_max_numa_distance; 2039 extern bool find_numa_distance(int distance); 2040 extern void sched_init_numa(int offline_node); 2041 extern void sched_update_numa(int cpu, bool online); 2042 extern void sched_domains_numa_masks_set(unsigned int cpu); 2043 extern void sched_domains_numa_masks_clear(unsigned int cpu); 2044 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu); 2045 2046 #else /* !CONFIG_NUMA: */ 2047 2048 static inline void sched_init_numa(int offline_node) { } 2049 static inline void sched_update_numa(int cpu, bool online) { } 2050 static inline void sched_domains_numa_masks_set(unsigned int cpu) { } 2051 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { } 2052 2053 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu) 2054 { 2055 return nr_cpu_ids; 2056 } 2057 2058 #endif /* !CONFIG_NUMA */ 2059 2060 #ifdef CONFIG_NUMA_BALANCING 2061 2062 /* The regions in numa_faults array from task_struct */ 2063 enum numa_faults_stats { 2064 NUMA_MEM = 0, 2065 NUMA_CPU, 2066 NUMA_MEMBUF, 2067 NUMA_CPUBUF 2068 }; 2069 2070 extern void sched_setnuma(struct task_struct *p, int node); 2071 extern int migrate_task_to(struct task_struct *p, int cpu); 2072 extern int migrate_swap(struct task_struct *p, struct task_struct *t, 2073 int cpu, int scpu); 2074 extern void init_numa_balancing(u64 clone_flags, struct task_struct *p); 2075 2076 #else /* !CONFIG_NUMA_BALANCING: */ 2077 2078 static inline void 2079 init_numa_balancing(u64 clone_flags, struct task_struct *p) 2080 { 2081 } 2082 2083 #endif /* !CONFIG_NUMA_BALANCING */ 2084 2085 static inline void 2086 queue_balance_callback(struct rq *rq, 2087 struct balance_callback *head, 2088 void (*func)(struct rq *rq)) 2089 { 2090 lockdep_assert_rq_held(rq); 2091 2092 /* 2093 * Don't (re)queue an already queued item; nor queue anything when 2094 * balance_push() is active, see the comment with 2095 * balance_push_callback. 2096 */ 2097 if (unlikely(head->next || rq->balance_callback == &balance_push_callback)) 2098 return; 2099 2100 head->func = func; 2101 head->next = rq->balance_callback; 2102 rq->balance_callback = head; 2103 } 2104 2105 #define rcu_dereference_sched_domain(p) \ 2106 rcu_dereference_all_check((p), lockdep_is_held(&sched_domains_mutex)) 2107 2108 /* 2109 * The domain tree (rq->sd) is protected by RCU's quiescent state transition. 2110 * See destroy_sched_domains: call_rcu for details. 2111 * 2112 * The domain tree of any CPU may only be accessed from within 2113 * preempt-disabled sections. 2114 */ 2115 #define for_each_domain(cpu, __sd) \ 2116 for (__sd = rcu_dereference_sched_domain(cpu_rq(cpu)->sd); \ 2117 __sd; __sd = __sd->parent) 2118 2119 /* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */ 2120 #define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) | 2121 static const unsigned int SD_SHARED_CHILD_MASK = 2122 #include <linux/sched/sd_flags.h> 2123 0; 2124 #undef SD_FLAG 2125 2126 /** 2127 * highest_flag_domain - Return highest sched_domain containing flag. 2128 * @cpu: The CPU whose highest level of sched domain is to 2129 * be returned. 2130 * @flag: The flag to check for the highest sched_domain 2131 * for the given CPU. 2132 * 2133 * Returns the highest sched_domain of a CPU which contains @flag. If @flag has 2134 * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag. 2135 */ 2136 static inline struct sched_domain *highest_flag_domain(int cpu, int flag) 2137 { 2138 struct sched_domain *sd, *hsd = NULL; 2139 2140 for_each_domain(cpu, sd) { 2141 if (sd->flags & flag) { 2142 hsd = sd; 2143 continue; 2144 } 2145 2146 /* 2147 * Stop the search if @flag is known to be shared at lower 2148 * levels. It will not be found further up. 2149 */ 2150 if (flag & SD_SHARED_CHILD_MASK) 2151 break; 2152 } 2153 2154 return hsd; 2155 } 2156 2157 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) 2158 { 2159 struct sched_domain *sd; 2160 2161 for_each_domain(cpu, sd) { 2162 if (sd->flags & flag) 2163 break; 2164 } 2165 2166 return sd; 2167 } 2168 2169 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc); 2170 DECLARE_PER_CPU(int, sd_llc_size); 2171 DECLARE_PER_CPU(int, sd_llc_id); 2172 DECLARE_PER_CPU(int, sd_share_id); 2173 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared); 2174 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa); 2175 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing); 2176 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity); 2177 2178 extern struct static_key_false sched_asym_cpucapacity; 2179 extern struct static_key_false sched_cluster_active; 2180 2181 static __always_inline bool sched_asym_cpucap_active(void) 2182 { 2183 return static_branch_unlikely(&sched_asym_cpucapacity); 2184 } 2185 2186 struct sched_group_capacity { 2187 atomic_t ref; 2188 /* 2189 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity 2190 * for a single CPU. 2191 */ 2192 unsigned long capacity; 2193 unsigned long min_capacity; /* Min per-CPU capacity in group */ 2194 unsigned long max_capacity; /* Max per-CPU capacity in group */ 2195 unsigned long next_update; 2196 int imbalance; /* XXX unrelated to capacity but shared group state */ 2197 2198 int id; 2199 2200 unsigned long cpumask[]; /* Balance mask */ 2201 }; 2202 2203 struct sched_group { 2204 struct sched_group *next; /* Must be a circular list */ 2205 atomic_t ref; 2206 2207 unsigned int group_weight; 2208 unsigned int cores; 2209 struct sched_group_capacity *sgc; 2210 int asym_prefer_cpu; /* CPU of highest priority in group */ 2211 int flags; 2212 2213 /* 2214 * The CPUs this group covers. 2215 * 2216 * NOTE: this field is variable length. (Allocated dynamically 2217 * by attaching extra space to the end of the structure, 2218 * depending on how many CPUs the kernel has booted up with) 2219 */ 2220 unsigned long cpumask[]; 2221 }; 2222 2223 static inline struct cpumask *sched_group_span(struct sched_group *sg) 2224 { 2225 return to_cpumask(sg->cpumask); 2226 } 2227 2228 /* 2229 * See build_balance_mask(). 2230 */ 2231 static inline struct cpumask *group_balance_mask(struct sched_group *sg) 2232 { 2233 return to_cpumask(sg->sgc->cpumask); 2234 } 2235 2236 extern int group_balance_cpu(struct sched_group *sg); 2237 2238 extern void update_sched_domain_debugfs(void); 2239 extern void dirty_sched_domain_sysctl(int cpu); 2240 2241 extern int sched_update_scaling(void); 2242 2243 static inline const struct cpumask *task_user_cpus(struct task_struct *p) 2244 { 2245 if (!p->user_cpus_ptr) 2246 return cpu_possible_mask; /* &init_task.cpus_mask */ 2247 return p->user_cpus_ptr; 2248 } 2249 2250 #ifdef CONFIG_CGROUP_SCHED 2251 2252 /* 2253 * Return the group to which this tasks belongs. 2254 * 2255 * We cannot use task_css() and friends because the cgroup subsystem 2256 * changes that value before the cgroup_subsys::attach() method is called, 2257 * therefore we cannot pin it and might observe the wrong value. 2258 * 2259 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup 2260 * core changes this before calling sched_move_task(). 2261 * 2262 * Instead we use a 'copy' which is updated from sched_move_task() while 2263 * holding both task_struct::pi_lock and rq::lock. 2264 */ 2265 static inline struct task_group *task_group(struct task_struct *p) 2266 { 2267 return p->sched_task_group; 2268 } 2269 2270 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ 2271 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) 2272 { 2273 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED) 2274 struct task_group *tg = task_group(p); 2275 #endif 2276 2277 #ifdef CONFIG_FAIR_GROUP_SCHED 2278 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]); 2279 p->se.cfs_rq = tg->cfs_rq[cpu]; 2280 p->se.parent = tg->se[cpu]; 2281 p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0; 2282 #endif 2283 2284 #ifdef CONFIG_RT_GROUP_SCHED 2285 /* 2286 * p->rt.rt_rq is NULL initially and it is easier to assign 2287 * root_task_group's rt_rq than switching in rt_rq_of_se() 2288 * Clobbers tg(!) 2289 */ 2290 if (!rt_group_sched_enabled()) 2291 tg = &root_task_group; 2292 p->rt.rt_rq = tg->rt_rq[cpu]; 2293 p->rt.parent = tg->rt_se[cpu]; 2294 #endif /* CONFIG_RT_GROUP_SCHED */ 2295 } 2296 2297 #else /* !CONFIG_CGROUP_SCHED: */ 2298 2299 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } 2300 2301 static inline struct task_group *task_group(struct task_struct *p) 2302 { 2303 return NULL; 2304 } 2305 2306 #endif /* !CONFIG_CGROUP_SCHED */ 2307 2308 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) 2309 { 2310 set_task_rq(p, cpu); 2311 #ifdef CONFIG_SMP 2312 /* 2313 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be 2314 * successfully executed on another CPU. We must ensure that updates of 2315 * per-task data have been completed by this moment. 2316 */ 2317 smp_wmb(); 2318 WRITE_ONCE(task_thread_info(p)->cpu, cpu); 2319 p->wake_cpu = cpu; 2320 rseq_sched_set_ids_changed(p); 2321 #endif /* CONFIG_SMP */ 2322 } 2323 2324 /* 2325 * Tunables: 2326 */ 2327 2328 #define SCHED_FEAT(name, enabled) \ 2329 __SCHED_FEAT_##name , 2330 2331 enum { 2332 #include "features.h" 2333 __SCHED_FEAT_NR, 2334 }; 2335 2336 #undef SCHED_FEAT 2337 2338 /* 2339 * To support run-time toggling of sched features, all the translation units 2340 * (but core.c) reference the sysctl_sched_features defined in core.c. 2341 */ 2342 extern __read_mostly unsigned int sysctl_sched_features; 2343 2344 #ifdef CONFIG_JUMP_LABEL 2345 2346 #define SCHED_FEAT(name, enabled) \ 2347 static __always_inline bool static_branch_##name(struct static_key *key) \ 2348 { \ 2349 return static_key_##enabled(key); \ 2350 } 2351 2352 #include "features.h" 2353 #undef SCHED_FEAT 2354 2355 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR]; 2356 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x])) 2357 2358 #else /* !CONFIG_JUMP_LABEL: */ 2359 2360 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) 2361 2362 #endif /* !CONFIG_JUMP_LABEL */ 2363 2364 extern struct static_key_false sched_numa_balancing; 2365 extern struct static_key_false sched_schedstats; 2366 2367 static inline u64 global_rt_period(void) 2368 { 2369 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC; 2370 } 2371 2372 static inline u64 global_rt_runtime(void) 2373 { 2374 if (sysctl_sched_rt_runtime < 0) 2375 return RUNTIME_INF; 2376 2377 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC; 2378 } 2379 2380 /* 2381 * Is p the current execution context? 2382 */ 2383 static inline int task_current(struct rq *rq, struct task_struct *p) 2384 { 2385 return rq->curr == p; 2386 } 2387 2388 /* 2389 * Is p the current scheduling context? 2390 * 2391 * Note that it might be the current execution context at the same time if 2392 * rq->curr == rq->donor == p. 2393 */ 2394 static inline int task_current_donor(struct rq *rq, struct task_struct *p) 2395 { 2396 return rq->donor == p; 2397 } 2398 2399 static inline bool task_is_blocked(struct task_struct *p) 2400 { 2401 if (!sched_proxy_exec()) 2402 return false; 2403 2404 return !!p->blocked_on; 2405 } 2406 2407 static inline int task_on_cpu(struct rq *rq, struct task_struct *p) 2408 { 2409 return p->on_cpu; 2410 } 2411 2412 static inline int task_on_rq_queued(struct task_struct *p) 2413 { 2414 return READ_ONCE(p->on_rq) == TASK_ON_RQ_QUEUED; 2415 } 2416 2417 static inline int task_on_rq_migrating(struct task_struct *p) 2418 { 2419 return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING; 2420 } 2421 2422 /* Wake flags. The first three directly map to some SD flag value */ 2423 #define WF_EXEC 0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */ 2424 #define WF_FORK 0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */ 2425 #define WF_TTWU 0x08 /* Wakeup; maps to SD_BALANCE_WAKE */ 2426 2427 #define WF_SYNC 0x10 /* Waker goes to sleep after wakeup */ 2428 #define WF_MIGRATED 0x20 /* Internal use, task got migrated */ 2429 #define WF_CURRENT_CPU 0x40 /* Prefer to move the wakee to the current CPU. */ 2430 #define WF_RQ_SELECTED 0x80 /* ->select_task_rq() was called */ 2431 2432 static_assert(WF_EXEC == SD_BALANCE_EXEC); 2433 static_assert(WF_FORK == SD_BALANCE_FORK); 2434 static_assert(WF_TTWU == SD_BALANCE_WAKE); 2435 2436 /* 2437 * To aid in avoiding the subversion of "niceness" due to uneven distribution 2438 * of tasks with abnormal "nice" values across CPUs the contribution that 2439 * each task makes to its run queue's load is weighted according to its 2440 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a 2441 * scaled version of the new time slice allocation that they receive on time 2442 * slice expiry etc. 2443 */ 2444 2445 #define WEIGHT_IDLEPRIO 3 2446 #define WMULT_IDLEPRIO 1431655765 2447 2448 extern const int sched_prio_to_weight[40]; 2449 extern const u32 sched_prio_to_wmult[40]; 2450 2451 /* 2452 * {de,en}queue flags: 2453 * 2454 * SLEEP/WAKEUP - task is no-longer/just-became runnable 2455 * 2456 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks 2457 * are in a known state which allows modification. Such pairs 2458 * should preserve as much state as possible. 2459 * 2460 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location 2461 * in the runqueue. IOW the priority is allowed to change. Callers 2462 * must expect to deal with balance callbacks. 2463 * 2464 * NOCLOCK - skip the update_rq_clock() (avoids double updates) 2465 * 2466 * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE) 2467 * 2468 * DELAYED - de/re-queue a sched_delayed task 2469 * 2470 * CLASS - going to update p->sched_class; makes sched_change call the 2471 * various switch methods. 2472 * 2473 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified) 2474 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline) 2475 * ENQUEUE_MIGRATED - the task was migrated during wakeup 2476 * ENQUEUE_RQ_SELECTED - ->select_task_rq() was called 2477 * 2478 * XXX SAVE/RESTORE in combination with CLASS doesn't really make sense, but 2479 * SCHED_DEADLINE seems to rely on this for now. 2480 */ 2481 2482 #define DEQUEUE_SLEEP 0x0001 /* Matches ENQUEUE_WAKEUP */ 2483 #define DEQUEUE_SAVE 0x0002 /* Matches ENQUEUE_RESTORE */ 2484 #define DEQUEUE_MOVE 0x0004 /* Matches ENQUEUE_MOVE */ 2485 #define DEQUEUE_NOCLOCK 0x0008 /* Matches ENQUEUE_NOCLOCK */ 2486 2487 #define DEQUEUE_MIGRATING 0x0010 /* Matches ENQUEUE_MIGRATING */ 2488 #define DEQUEUE_DELAYED 0x0020 /* Matches ENQUEUE_DELAYED */ 2489 #define DEQUEUE_CLASS 0x0040 /* Matches ENQUEUE_CLASS */ 2490 2491 #define DEQUEUE_SPECIAL 0x00010000 2492 #define DEQUEUE_THROTTLE 0x00020000 2493 2494 #define ENQUEUE_WAKEUP 0x0001 2495 #define ENQUEUE_RESTORE 0x0002 2496 #define ENQUEUE_MOVE 0x0004 2497 #define ENQUEUE_NOCLOCK 0x0008 2498 2499 #define ENQUEUE_MIGRATING 0x0010 2500 #define ENQUEUE_DELAYED 0x0020 2501 #define ENQUEUE_CLASS 0x0040 2502 2503 #define ENQUEUE_HEAD 0x00010000 2504 #define ENQUEUE_REPLENISH 0x00020000 2505 #define ENQUEUE_MIGRATED 0x00040000 2506 #define ENQUEUE_INITIAL 0x00080000 2507 #define ENQUEUE_RQ_SELECTED 0x00100000 2508 2509 #define RETRY_TASK ((void *)-1UL) 2510 2511 struct affinity_context { 2512 const struct cpumask *new_mask; 2513 struct cpumask *user_mask; 2514 unsigned int flags; 2515 }; 2516 2517 extern s64 update_curr_common(struct rq *rq); 2518 2519 struct sched_class { 2520 2521 #ifdef CONFIG_UCLAMP_TASK 2522 int uclamp_enabled; 2523 #endif 2524 2525 /* 2526 * move_queued_task/activate_task/enqueue_task: rq->lock 2527 * ttwu_do_activate/activate_task/enqueue_task: rq->lock 2528 * wake_up_new_task/activate_task/enqueue_task: task_rq_lock 2529 * ttwu_runnable/enqueue_task: task_rq_lock 2530 * proxy_task_current: rq->lock 2531 * sched_change_end 2532 */ 2533 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags); 2534 /* 2535 * move_queued_task/deactivate_task/dequeue_task: rq->lock 2536 * __schedule/block_task/dequeue_task: rq->lock 2537 * proxy_task_current: rq->lock 2538 * wait_task_inactive: task_rq_lock 2539 * sched_change_begin 2540 */ 2541 bool (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags); 2542 2543 /* 2544 * do_sched_yield: rq->lock 2545 */ 2546 void (*yield_task) (struct rq *rq); 2547 /* 2548 * yield_to: rq->lock (double) 2549 */ 2550 bool (*yield_to_task)(struct rq *rq, struct task_struct *p); 2551 2552 /* 2553 * move_queued_task: rq->lock 2554 * __migrate_swap_task: rq->lock 2555 * ttwu_do_activate: rq->lock 2556 * ttwu_runnable: task_rq_lock 2557 * wake_up_new_task: task_rq_lock 2558 */ 2559 void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags); 2560 2561 /* 2562 * schedule/pick_next_task/prev_balance: rq->lock 2563 */ 2564 int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf); 2565 2566 /* 2567 * schedule/pick_next_task: rq->lock 2568 */ 2569 struct task_struct *(*pick_task)(struct rq *rq, struct rq_flags *rf); 2570 /* 2571 * Optional! When implemented pick_next_task() should be equivalent to: 2572 * 2573 * next = pick_task(); 2574 * if (next) { 2575 * put_prev_task(prev); 2576 * set_next_task_first(next); 2577 * } 2578 */ 2579 struct task_struct *(*pick_next_task)(struct rq *rq, struct task_struct *prev, 2580 struct rq_flags *rf); 2581 2582 /* 2583 * sched_change: 2584 * __schedule: rq->lock 2585 */ 2586 void (*put_prev_task)(struct rq *rq, struct task_struct *p, struct task_struct *next); 2587 void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first); 2588 2589 /* 2590 * select_task_rq: p->pi_lock 2591 * sched_exec: p->pi_lock 2592 */ 2593 int (*select_task_rq)(struct task_struct *p, int task_cpu, int flags); 2594 2595 /* 2596 * set_task_cpu: p->pi_lock || rq->lock (ttwu like) 2597 */ 2598 void (*migrate_task_rq)(struct task_struct *p, int new_cpu); 2599 2600 /* 2601 * ttwu_do_activate: rq->lock 2602 * wake_up_new_task: task_rq_lock 2603 */ 2604 void (*task_woken)(struct rq *this_rq, struct task_struct *task); 2605 2606 /* 2607 * do_set_cpus_allowed: task_rq_lock + sched_change 2608 */ 2609 void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx); 2610 2611 /* 2612 * sched_set_rq_{on,off}line: rq->lock 2613 */ 2614 void (*rq_online)(struct rq *rq); 2615 void (*rq_offline)(struct rq *rq); 2616 2617 /* 2618 * push_cpu_stop: p->pi_lock && rq->lock 2619 */ 2620 struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq); 2621 2622 /* 2623 * hrtick: rq->lock 2624 * sched_tick: rq->lock 2625 * sched_tick_remote: rq->lock 2626 */ 2627 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued); 2628 /* 2629 * sched_cgroup_fork: p->pi_lock 2630 */ 2631 void (*task_fork)(struct task_struct *p); 2632 /* 2633 * finish_task_switch: no locks 2634 */ 2635 void (*task_dead)(struct task_struct *p); 2636 2637 /* 2638 * sched_change 2639 */ 2640 void (*switching_from)(struct rq *this_rq, struct task_struct *task); 2641 void (*switched_from) (struct rq *this_rq, struct task_struct *task); 2642 void (*switching_to) (struct rq *this_rq, struct task_struct *task); 2643 void (*switched_to) (struct rq *this_rq, struct task_struct *task); 2644 u64 (*get_prio) (struct rq *this_rq, struct task_struct *task); 2645 void (*prio_changed) (struct rq *this_rq, struct task_struct *task, 2646 u64 oldprio); 2647 2648 /* 2649 * set_load_weight: task_rq_lock + sched_change 2650 * __setscheduler_parms: task_rq_lock + sched_change 2651 */ 2652 void (*reweight_task)(struct rq *this_rq, struct task_struct *task, 2653 const struct load_weight *lw); 2654 2655 /* 2656 * sched_rr_get_interval: task_rq_lock 2657 */ 2658 unsigned int (*get_rr_interval)(struct rq *rq, 2659 struct task_struct *task); 2660 2661 /* 2662 * task_sched_runtime: task_rq_lock 2663 */ 2664 void (*update_curr)(struct rq *rq); 2665 2666 #ifdef CONFIG_FAIR_GROUP_SCHED 2667 /* 2668 * sched_change_group: task_rq_lock + sched_change 2669 */ 2670 void (*task_change_group)(struct task_struct *p); 2671 #endif 2672 2673 #ifdef CONFIG_SCHED_CORE 2674 /* 2675 * pick_next_task: rq->lock 2676 * try_steal_cookie: rq->lock (double) 2677 */ 2678 int (*task_is_throttled)(struct task_struct *p, int cpu); 2679 #endif 2680 }; 2681 2682 static inline void put_prev_task(struct rq *rq, struct task_struct *prev) 2683 { 2684 WARN_ON_ONCE(rq->donor != prev); 2685 prev->sched_class->put_prev_task(rq, prev, NULL); 2686 } 2687 2688 static inline void set_next_task(struct rq *rq, struct task_struct *next) 2689 { 2690 next->sched_class->set_next_task(rq, next, false); 2691 } 2692 2693 static inline void 2694 __put_prev_set_next_dl_server(struct rq *rq, 2695 struct task_struct *prev, 2696 struct task_struct *next) 2697 { 2698 prev->dl_server = NULL; 2699 next->dl_server = rq->dl_server; 2700 rq->dl_server = NULL; 2701 } 2702 2703 static inline void put_prev_set_next_task(struct rq *rq, 2704 struct task_struct *prev, 2705 struct task_struct *next) 2706 { 2707 WARN_ON_ONCE(rq->donor != prev); 2708 2709 __put_prev_set_next_dl_server(rq, prev, next); 2710 2711 if (next == prev) 2712 return; 2713 2714 prev->sched_class->put_prev_task(rq, prev, next); 2715 next->sched_class->set_next_task(rq, next, true); 2716 } 2717 2718 /* 2719 * Helper to define a sched_class instance; each one is placed in a separate 2720 * section which is ordered by the linker script: 2721 * 2722 * include/asm-generic/vmlinux.lds.h 2723 * 2724 * *CAREFUL* they are laid out in *REVERSE* order!!! 2725 * 2726 * Also enforce alignment on the instance, not the type, to guarantee layout. 2727 */ 2728 #define DEFINE_SCHED_CLASS(name) \ 2729 const struct sched_class name##_sched_class \ 2730 __aligned(__alignof__(struct sched_class)) \ 2731 __section("__" #name "_sched_class") 2732 2733 /* Defined in include/asm-generic/vmlinux.lds.h */ 2734 extern struct sched_class __sched_class_highest[]; 2735 extern struct sched_class __sched_class_lowest[]; 2736 2737 extern const struct sched_class stop_sched_class; 2738 extern const struct sched_class dl_sched_class; 2739 extern const struct sched_class rt_sched_class; 2740 extern const struct sched_class fair_sched_class; 2741 extern const struct sched_class idle_sched_class; 2742 2743 /* 2744 * Iterate only active classes. SCX can take over all fair tasks or be 2745 * completely disabled. If the former, skip fair. If the latter, skip SCX. 2746 */ 2747 static inline const struct sched_class *next_active_class(const struct sched_class *class) 2748 { 2749 class++; 2750 #ifdef CONFIG_SCHED_CLASS_EXT 2751 if (scx_switched_all() && class == &fair_sched_class) 2752 class++; 2753 if (!scx_enabled() && class == &ext_sched_class) 2754 class++; 2755 #endif 2756 return class; 2757 } 2758 2759 #define for_class_range(class, _from, _to) \ 2760 for (class = (_from); class < (_to); class++) 2761 2762 #define for_each_class(class) \ 2763 for_class_range(class, __sched_class_highest, __sched_class_lowest) 2764 2765 #define for_active_class_range(class, _from, _to) \ 2766 for (class = (_from); class != (_to); class = next_active_class(class)) 2767 2768 #define for_each_active_class(class) \ 2769 for_active_class_range(class, __sched_class_highest, __sched_class_lowest) 2770 2771 #define sched_class_above(_a, _b) ((_a) < (_b)) 2772 2773 static inline void rq_modified_begin(struct rq *rq, const struct sched_class *class) 2774 { 2775 if (sched_class_above(rq->next_class, class)) 2776 rq->next_class = class; 2777 } 2778 2779 static inline bool rq_modified_above(struct rq *rq, const struct sched_class *class) 2780 { 2781 return sched_class_above(rq->next_class, class); 2782 } 2783 2784 static inline bool sched_stop_runnable(struct rq *rq) 2785 { 2786 return rq->stop && task_on_rq_queued(rq->stop); 2787 } 2788 2789 static inline bool sched_dl_runnable(struct rq *rq) 2790 { 2791 return rq->dl.dl_nr_running > 0; 2792 } 2793 2794 static inline bool sched_rt_runnable(struct rq *rq) 2795 { 2796 return rq->rt.rt_queued > 0; 2797 } 2798 2799 static inline bool sched_fair_runnable(struct rq *rq) 2800 { 2801 return rq->cfs.nr_queued > 0; 2802 } 2803 2804 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, 2805 struct rq_flags *rf); 2806 extern struct task_struct *pick_task_idle(struct rq *rq, struct rq_flags *rf); 2807 2808 #define SCA_CHECK 0x01 2809 #define SCA_MIGRATE_DISABLE 0x02 2810 #define SCA_MIGRATE_ENABLE 0x04 2811 #define SCA_USER 0x08 2812 2813 extern void update_group_capacity(struct sched_domain *sd, int cpu); 2814 2815 extern void sched_balance_trigger(struct rq *rq); 2816 2817 extern int __set_cpus_allowed_ptr(struct task_struct *p, struct affinity_context *ctx); 2818 extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx); 2819 2820 static inline bool task_allowed_on_cpu(struct task_struct *p, int cpu) 2821 { 2822 /* When not in the task's cpumask, no point in looking further. */ 2823 if (!cpumask_test_cpu(cpu, p->cpus_ptr)) 2824 return false; 2825 2826 /* Can @cpu run a user thread? */ 2827 if (!(p->flags & PF_KTHREAD) && !task_cpu_possible(cpu, p)) 2828 return false; 2829 2830 return true; 2831 } 2832 2833 static inline cpumask_t *alloc_user_cpus_ptr(int node) 2834 { 2835 /* 2836 * See set_cpus_allowed_force() above for the rcu_head usage. 2837 */ 2838 int size = max_t(int, cpumask_size(), sizeof(struct rcu_head)); 2839 2840 return kmalloc_node(size, GFP_KERNEL, node); 2841 } 2842 2843 static inline struct task_struct *get_push_task(struct rq *rq) 2844 { 2845 struct task_struct *p = rq->donor; 2846 2847 lockdep_assert_rq_held(rq); 2848 2849 if (rq->push_busy) 2850 return NULL; 2851 2852 if (p->nr_cpus_allowed == 1) 2853 return NULL; 2854 2855 if (p->migration_disabled) 2856 return NULL; 2857 2858 rq->push_busy = true; 2859 return get_task_struct(p); 2860 } 2861 2862 extern int push_cpu_stop(void *arg); 2863 2864 #ifdef CONFIG_CPU_IDLE 2865 2866 static inline void idle_set_state(struct rq *rq, 2867 struct cpuidle_state *idle_state) 2868 { 2869 rq->idle_state = idle_state; 2870 } 2871 2872 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 2873 { 2874 lockdep_assert(rcu_read_lock_any_held()); 2875 2876 return rq->idle_state; 2877 } 2878 2879 #else /* !CONFIG_CPU_IDLE: */ 2880 2881 static inline void idle_set_state(struct rq *rq, 2882 struct cpuidle_state *idle_state) 2883 { 2884 } 2885 2886 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 2887 { 2888 return NULL; 2889 } 2890 2891 #endif /* !CONFIG_CPU_IDLE */ 2892 2893 extern void schedule_idle(void); 2894 asmlinkage void schedule_user(void); 2895 2896 extern void sysrq_sched_debug_show(void); 2897 extern void sched_init_granularity(void); 2898 extern void update_max_interval(void); 2899 2900 extern void init_sched_dl_class(void); 2901 extern void init_sched_rt_class(void); 2902 extern void init_sched_fair_class(void); 2903 2904 extern void resched_curr(struct rq *rq); 2905 extern void resched_curr_lazy(struct rq *rq); 2906 extern void resched_cpu(int cpu); 2907 2908 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime); 2909 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq); 2910 2911 extern void init_dl_entity(struct sched_dl_entity *dl_se); 2912 2913 extern void init_cfs_throttle_work(struct task_struct *p); 2914 2915 #define BW_SHIFT 20 2916 #define BW_UNIT (1 << BW_SHIFT) 2917 #define RATIO_SHIFT 8 2918 #define MAX_BW_BITS (64 - BW_SHIFT) 2919 #define MAX_BW ((1ULL << MAX_BW_BITS) - 1) 2920 2921 extern u64 to_ratio(u64 period, u64 runtime); 2922 2923 extern void init_entity_runnable_average(struct sched_entity *se); 2924 extern void post_init_entity_util_avg(struct task_struct *p); 2925 2926 #ifdef CONFIG_NO_HZ_FULL 2927 extern bool sched_can_stop_tick(struct rq *rq); 2928 extern int __init sched_tick_offload_init(void); 2929 2930 /* 2931 * Tick may be needed by tasks in the runqueue depending on their policy and 2932 * requirements. If tick is needed, lets send the target an IPI to kick it out of 2933 * nohz mode if necessary. 2934 */ 2935 static inline void sched_update_tick_dependency(struct rq *rq) 2936 { 2937 int cpu = cpu_of(rq); 2938 2939 if (!tick_nohz_full_cpu(cpu)) 2940 return; 2941 2942 if (sched_can_stop_tick(rq)) 2943 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED); 2944 else 2945 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED); 2946 } 2947 #else /* !CONFIG_NO_HZ_FULL: */ 2948 static inline int sched_tick_offload_init(void) { return 0; } 2949 static inline void sched_update_tick_dependency(struct rq *rq) { } 2950 #endif /* !CONFIG_NO_HZ_FULL */ 2951 2952 static inline void add_nr_running(struct rq *rq, unsigned count) 2953 { 2954 unsigned prev_nr = rq->nr_running; 2955 2956 rq->nr_running = prev_nr + count; 2957 if (trace_sched_update_nr_running_tp_enabled()) { 2958 call_trace_sched_update_nr_running(rq, count); 2959 } 2960 2961 if (prev_nr < 2 && rq->nr_running >= 2) 2962 set_rd_overloaded(rq->rd, 1); 2963 2964 sched_update_tick_dependency(rq); 2965 } 2966 2967 static inline void sub_nr_running(struct rq *rq, unsigned count) 2968 { 2969 rq->nr_running -= count; 2970 if (trace_sched_update_nr_running_tp_enabled()) { 2971 call_trace_sched_update_nr_running(rq, -count); 2972 } 2973 2974 /* Check if we still need preemption */ 2975 sched_update_tick_dependency(rq); 2976 } 2977 2978 static inline void __block_task(struct rq *rq, struct task_struct *p) 2979 { 2980 if (p->sched_contributes_to_load) 2981 rq->nr_uninterruptible++; 2982 2983 if (p->in_iowait) { 2984 atomic_inc(&rq->nr_iowait); 2985 delayacct_blkio_start(); 2986 } 2987 2988 ASSERT_EXCLUSIVE_WRITER(p->on_rq); 2989 2990 /* 2991 * The moment this write goes through, ttwu() can swoop in and migrate 2992 * this task, rendering our rq->__lock ineffective. 2993 * 2994 * __schedule() try_to_wake_up() 2995 * LOCK rq->__lock LOCK p->pi_lock 2996 * pick_next_task() 2997 * pick_next_task_fair() 2998 * pick_next_entity() 2999 * dequeue_entities() 3000 * __block_task() 3001 * RELEASE p->on_rq = 0 if (p->on_rq && ...) 3002 * break; 3003 * 3004 * ACQUIRE (after ctrl-dep) 3005 * 3006 * cpu = select_task_rq(); 3007 * set_task_cpu(p, cpu); 3008 * ttwu_queue() 3009 * ttwu_do_activate() 3010 * LOCK rq->__lock 3011 * activate_task() 3012 * STORE p->on_rq = 1 3013 * UNLOCK rq->__lock 3014 * 3015 * Callers must ensure to not reference @p after this -- we no longer 3016 * own it. 3017 */ 3018 smp_store_release(&p->on_rq, 0); 3019 } 3020 3021 extern void activate_task(struct rq *rq, struct task_struct *p, int flags); 3022 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags); 3023 3024 extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags); 3025 3026 /* 3027 * attach_task() -- attach the task detached by detach_task() to its new rq. 3028 */ 3029 static inline void attach_task(struct rq *rq, struct task_struct *p) 3030 { 3031 lockdep_assert_rq_held(rq); 3032 3033 WARN_ON_ONCE(task_rq(p) != rq); 3034 activate_task(rq, p, ENQUEUE_NOCLOCK); 3035 wakeup_preempt(rq, p, 0); 3036 } 3037 3038 /* 3039 * attach_one_task() -- attaches the task returned from detach_one_task() to 3040 * its new rq. 3041 */ 3042 static inline void attach_one_task(struct rq *rq, struct task_struct *p) 3043 { 3044 guard(rq_lock)(rq); 3045 update_rq_clock(rq); 3046 attach_task(rq, p); 3047 } 3048 3049 #ifdef CONFIG_PREEMPT_RT 3050 # define SCHED_NR_MIGRATE_BREAK 8 3051 #else 3052 # define SCHED_NR_MIGRATE_BREAK 32 3053 #endif 3054 3055 extern __read_mostly unsigned int sysctl_sched_nr_migrate; 3056 extern __read_mostly unsigned int sysctl_sched_migration_cost; 3057 3058 extern unsigned int sysctl_sched_base_slice; 3059 3060 extern int sysctl_resched_latency_warn_ms; 3061 extern int sysctl_resched_latency_warn_once; 3062 3063 extern unsigned int sysctl_sched_tunable_scaling; 3064 3065 extern unsigned int sysctl_numa_balancing_scan_delay; 3066 extern unsigned int sysctl_numa_balancing_scan_period_min; 3067 extern unsigned int sysctl_numa_balancing_scan_period_max; 3068 extern unsigned int sysctl_numa_balancing_scan_size; 3069 extern unsigned int sysctl_numa_balancing_hot_threshold; 3070 3071 #ifdef CONFIG_SCHED_HRTICK 3072 3073 /* 3074 * Use hrtick when: 3075 * - enabled by features 3076 * - hrtimer is actually high res 3077 */ 3078 static inline bool hrtick_enabled(struct rq *rq) 3079 { 3080 return cpu_active(cpu_of(rq)) && hrtimer_highres_enabled(); 3081 } 3082 3083 static inline bool hrtick_enabled_fair(struct rq *rq) 3084 { 3085 return sched_feat(HRTICK) && hrtick_enabled(rq); 3086 } 3087 3088 static inline bool hrtick_enabled_dl(struct rq *rq) 3089 { 3090 return sched_feat(HRTICK_DL) && hrtick_enabled(rq); 3091 } 3092 3093 extern void hrtick_start(struct rq *rq, u64 delay); 3094 static inline bool hrtick_active(struct rq *rq) 3095 { 3096 return hrtimer_active(&rq->hrtick_timer); 3097 } 3098 3099 #else /* !CONFIG_SCHED_HRTICK: */ 3100 static inline bool hrtick_enabled_fair(struct rq *rq) { return false; } 3101 static inline bool hrtick_enabled_dl(struct rq *rq) { return false; } 3102 static inline bool hrtick_enabled(struct rq *rq) { return false; } 3103 #endif /* !CONFIG_SCHED_HRTICK */ 3104 3105 #ifndef arch_scale_freq_tick 3106 static __always_inline void arch_scale_freq_tick(void) { } 3107 #endif 3108 3109 #ifndef arch_scale_freq_capacity 3110 /** 3111 * arch_scale_freq_capacity - get the frequency scale factor of a given CPU. 3112 * @cpu: the CPU in question. 3113 * 3114 * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e. 3115 * 3116 * f_curr 3117 * ------ * SCHED_CAPACITY_SCALE 3118 * f_max 3119 */ 3120 static __always_inline 3121 unsigned long arch_scale_freq_capacity(int cpu) 3122 { 3123 return SCHED_CAPACITY_SCALE; 3124 } 3125 #endif 3126 3127 /* 3128 * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to 3129 * acquire rq lock instead of rq_lock(). So at the end of these two functions 3130 * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of 3131 * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning. 3132 */ 3133 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) 3134 { 3135 rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 3136 rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 3137 } 3138 3139 #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...) \ 3140 __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__) \ 3141 static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2) \ 3142 __no_context_analysis \ 3143 { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t; \ 3144 _lock; return _t; } 3145 #define DECLARE_LOCK_GUARD_2_ATTRS(_name, _lock, _unlock1, _unlock2) \ 3146 static inline class_##_name##_t class_##_name##_constructor(lock_##_name##_t *_T1, \ 3147 lock_##_name##_t *_T2) _lock; \ 3148 static __always_inline void __class_##_name##_cleanup_ctx1(class_##_name##_t **_T1) \ 3149 __no_context_analysis _unlock1 { } \ 3150 static __always_inline void __class_##_name##_cleanup_ctx2(class_##_name##_t **_T2) \ 3151 __no_context_analysis _unlock2 { } 3152 #define WITH_LOCK_GUARD_2_ATTRS(_name, _T1, _T2) \ 3153 class_##_name##_constructor(_T1, _T2), \ 3154 *__UNIQUE_ID(unlock1) __cleanup(__class_##_name##_cleanup_ctx1) = (void *)(_T1),\ 3155 *__UNIQUE_ID(unlock2) __cleanup(__class_##_name##_cleanup_ctx2) = (void *)(_T2) 3156 3157 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2) 3158 { 3159 #ifdef CONFIG_SCHED_CORE 3160 /* 3161 * In order to not have {0,2},{1,3} turn into into an AB-BA, 3162 * order by core-id first and cpu-id second. 3163 * 3164 * Notably: 3165 * 3166 * double_rq_lock(0,3); will take core-0, core-1 lock 3167 * double_rq_lock(1,2); will take core-1, core-0 lock 3168 * 3169 * when only cpu-id is considered. 3170 */ 3171 if (rq1->core->cpu < rq2->core->cpu) 3172 return true; 3173 if (rq1->core->cpu > rq2->core->cpu) 3174 return false; 3175 3176 /* 3177 * __sched_core_flip() relies on SMT having cpu-id lock order. 3178 */ 3179 #endif /* CONFIG_SCHED_CORE */ 3180 return rq1->cpu < rq2->cpu; 3181 } 3182 3183 extern void double_rq_lock(struct rq *rq1, struct rq *rq2) 3184 __acquires(__rq_lockp(rq1), __rq_lockp(rq2)); 3185 3186 #ifdef CONFIG_PREEMPTION 3187 3188 /* 3189 * fair double_lock_balance: Safely acquires both rq->locks in a fair 3190 * way at the expense of forcing extra atomic operations in all 3191 * invocations. This assures that the double_lock is acquired using the 3192 * same underlying policy as the spinlock_t on this architecture, which 3193 * reduces latency compared to the unfair variant below. However, it 3194 * also adds more overhead and therefore may reduce throughput. 3195 */ 3196 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 3197 __must_hold(__rq_lockp(this_rq)) 3198 __acquires(__rq_lockp(busiest)) 3199 { 3200 raw_spin_rq_unlock(this_rq); 3201 double_rq_lock(this_rq, busiest); 3202 3203 return 1; 3204 } 3205 3206 #else /* !CONFIG_PREEMPTION: */ 3207 /* 3208 * Unfair double_lock_balance: Optimizes throughput at the expense of 3209 * latency by eliminating extra atomic operations when the locks are 3210 * already in proper order on entry. This favors lower CPU-ids and will 3211 * grant the double lock to lower CPUs over higher ids under contention, 3212 * regardless of entry order into the function. 3213 */ 3214 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 3215 __must_hold(__rq_lockp(this_rq)) 3216 __acquires(__rq_lockp(busiest)) 3217 { 3218 if (__rq_lockp(this_rq) == __rq_lockp(busiest)) { 3219 __acquire(__rq_lockp(busiest)); /* already held */ 3220 double_rq_clock_clear_update(this_rq, busiest); 3221 return 0; 3222 } 3223 3224 if (likely(raw_spin_rq_trylock(busiest))) { 3225 double_rq_clock_clear_update(this_rq, busiest); 3226 return 0; 3227 } 3228 3229 if (rq_order_less(this_rq, busiest)) { 3230 raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING); 3231 double_rq_clock_clear_update(this_rq, busiest); 3232 return 0; 3233 } 3234 3235 raw_spin_rq_unlock(this_rq); 3236 double_rq_lock(this_rq, busiest); 3237 3238 return 1; 3239 } 3240 3241 #endif /* !CONFIG_PREEMPTION */ 3242 3243 /* 3244 * double_lock_balance - lock the busiest runqueue, this_rq is locked already. 3245 */ 3246 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest) 3247 __must_hold(__rq_lockp(this_rq)) 3248 __acquires(__rq_lockp(busiest)) 3249 { 3250 lockdep_assert_irqs_disabled(); 3251 3252 return _double_lock_balance(this_rq, busiest); 3253 } 3254 3255 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest) 3256 __releases(__rq_lockp(busiest)) 3257 { 3258 if (__rq_lockp(this_rq) != __rq_lockp(busiest)) 3259 raw_spin_rq_unlock(busiest); 3260 else 3261 __release(__rq_lockp(busiest)); /* fake release */ 3262 lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_); 3263 } 3264 3265 static inline void double_lock(spinlock_t *l1, spinlock_t *l2) 3266 __acquires(l1, l2) 3267 { 3268 if (l1 > l2) 3269 swap(l1, l2); 3270 3271 spin_lock(l1); 3272 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 3273 } 3274 3275 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2) 3276 __acquires(l1, l2) 3277 { 3278 if (l1 > l2) 3279 swap(l1, l2); 3280 3281 spin_lock_irq(l1); 3282 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 3283 } 3284 3285 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2) 3286 __acquires(l1, l2) 3287 { 3288 if (l1 > l2) 3289 swap(l1, l2); 3290 3291 raw_spin_lock(l1); 3292 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 3293 } 3294 3295 static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2) 3296 __releases(l1, l2) 3297 { 3298 raw_spin_unlock(l1); 3299 raw_spin_unlock(l2); 3300 } 3301 3302 DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t, 3303 double_raw_lock(_T->lock, _T->lock2), 3304 double_raw_unlock(_T->lock, _T->lock2)) 3305 3306 DECLARE_LOCK_GUARD_2_ATTRS(double_raw_spinlock, 3307 __acquires(_T1, _T2), 3308 __releases(*(raw_spinlock_t **)_T1), 3309 __releases(*(raw_spinlock_t **)_T2)); 3310 #define class_double_raw_spinlock_constructor(_T1, _T2) \ 3311 WITH_LOCK_GUARD_2_ATTRS(double_raw_spinlock, _T1, _T2) 3312 3313 /* 3314 * double_rq_unlock - safely unlock two runqueues 3315 * 3316 * Note this does not restore interrupts like task_rq_unlock, 3317 * you need to do so manually after calling. 3318 */ 3319 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 3320 __releases(__rq_lockp(rq1), __rq_lockp(rq2)) 3321 { 3322 if (__rq_lockp(rq1) != __rq_lockp(rq2)) 3323 raw_spin_rq_unlock(rq2); 3324 else 3325 __release(__rq_lockp(rq2)); /* fake release */ 3326 raw_spin_rq_unlock(rq1); 3327 } 3328 3329 extern void set_rq_online (struct rq *rq); 3330 extern void set_rq_offline(struct rq *rq); 3331 3332 extern bool sched_smp_initialized; 3333 3334 DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq, 3335 double_rq_lock(_T->lock, _T->lock2), 3336 double_rq_unlock(_T->lock, _T->lock2)) 3337 3338 extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq); 3339 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq); 3340 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq); 3341 3342 extern bool sched_debug_verbose; 3343 3344 extern void print_cfs_stats(struct seq_file *m, int cpu); 3345 extern void print_rt_stats(struct seq_file *m, int cpu); 3346 extern void print_dl_stats(struct seq_file *m, int cpu); 3347 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 3348 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq); 3349 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq); 3350 3351 extern void resched_latency_warn(int cpu, u64 latency); 3352 3353 #ifdef CONFIG_NUMA_BALANCING 3354 extern void show_numa_stats(struct task_struct *p, struct seq_file *m); 3355 extern void 3356 print_numa_stats(struct seq_file *m, int node, unsigned long tsf, 3357 unsigned long tpf, unsigned long gsf, unsigned long gpf); 3358 #endif /* CONFIG_NUMA_BALANCING */ 3359 3360 extern void init_cfs_rq(struct cfs_rq *cfs_rq); 3361 extern void init_rt_rq(struct rt_rq *rt_rq); 3362 extern void init_dl_rq(struct dl_rq *dl_rq); 3363 3364 extern void cfs_bandwidth_usage_inc(void); 3365 extern void cfs_bandwidth_usage_dec(void); 3366 3367 #ifdef CONFIG_NO_HZ_COMMON 3368 3369 #define NOHZ_BALANCE_KICK_BIT 0 3370 #define NOHZ_STATS_KICK_BIT 1 3371 #define NOHZ_NEWILB_KICK_BIT 2 3372 #define NOHZ_NEXT_KICK_BIT 3 3373 3374 /* Run sched_balance_domains() */ 3375 #define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT) 3376 /* Update blocked load */ 3377 #define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT) 3378 /* Update blocked load when entering idle */ 3379 #define NOHZ_NEWILB_KICK BIT(NOHZ_NEWILB_KICK_BIT) 3380 /* Update nohz.next_balance */ 3381 #define NOHZ_NEXT_KICK BIT(NOHZ_NEXT_KICK_BIT) 3382 3383 #define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK) 3384 3385 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags) 3386 3387 extern void nohz_balance_exit_idle(struct rq *rq); 3388 #else /* !CONFIG_NO_HZ_COMMON: */ 3389 static inline void nohz_balance_exit_idle(struct rq *rq) { } 3390 #endif /* !CONFIG_NO_HZ_COMMON */ 3391 3392 #ifdef CONFIG_NO_HZ_COMMON 3393 extern void nohz_run_idle_balance(int cpu); 3394 #else 3395 static inline void nohz_run_idle_balance(int cpu) { } 3396 #endif 3397 3398 #include "stats.h" 3399 3400 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS) 3401 3402 extern void __sched_core_account_forceidle(struct rq *rq); 3403 3404 static inline void sched_core_account_forceidle(struct rq *rq) 3405 { 3406 if (schedstat_enabled()) 3407 __sched_core_account_forceidle(rq); 3408 } 3409 3410 extern void __sched_core_tick(struct rq *rq); 3411 3412 static inline void sched_core_tick(struct rq *rq) 3413 { 3414 if (sched_core_enabled(rq) && schedstat_enabled()) 3415 __sched_core_tick(rq); 3416 } 3417 3418 #else /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS): */ 3419 3420 static inline void sched_core_account_forceidle(struct rq *rq) { } 3421 3422 static inline void sched_core_tick(struct rq *rq) { } 3423 3424 #endif /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS) */ 3425 3426 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 3427 3428 struct irqtime { 3429 u64 total; 3430 u64 tick_delta; 3431 u64 irq_start_time; 3432 struct u64_stats_sync sync; 3433 }; 3434 3435 DECLARE_PER_CPU(struct irqtime, cpu_irqtime); 3436 DECLARE_STATIC_KEY_FALSE(sched_clock_irqtime); 3437 3438 static inline int irqtime_enabled(void) 3439 { 3440 return static_branch_likely(&sched_clock_irqtime); 3441 } 3442 3443 /* 3444 * Returns the irqtime minus the softirq time computed by ksoftirqd. 3445 * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime 3446 * and never move forward. 3447 */ 3448 static inline u64 irq_time_read(int cpu) 3449 { 3450 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu); 3451 unsigned int seq; 3452 u64 total; 3453 3454 do { 3455 seq = __u64_stats_fetch_begin(&irqtime->sync); 3456 total = irqtime->total; 3457 } while (__u64_stats_fetch_retry(&irqtime->sync, seq)); 3458 3459 return total; 3460 } 3461 3462 #else /* !CONFIG_IRQ_TIME_ACCOUNTING: */ 3463 3464 static inline int irqtime_enabled(void) 3465 { 3466 return 0; 3467 } 3468 3469 #endif /* !CONFIG_IRQ_TIME_ACCOUNTING */ 3470 3471 #ifdef CONFIG_CPU_FREQ 3472 3473 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data); 3474 3475 /** 3476 * cpufreq_update_util - Take a note about CPU utilization changes. 3477 * @rq: Runqueue to carry out the update for. 3478 * @flags: Update reason flags. 3479 * 3480 * This function is called by the scheduler on the CPU whose utilization is 3481 * being updated. 3482 * 3483 * It can only be called from RCU-sched read-side critical sections. 3484 * 3485 * The way cpufreq is currently arranged requires it to evaluate the CPU 3486 * performance state (frequency/voltage) on a regular basis to prevent it from 3487 * being stuck in a completely inadequate performance level for too long. 3488 * That is not guaranteed to happen if the updates are only triggered from CFS 3489 * and DL, though, because they may not be coming in if only RT tasks are 3490 * active all the time (or there are RT tasks only). 3491 * 3492 * As a workaround for that issue, this function is called periodically by the 3493 * RT sched class to trigger extra cpufreq updates to prevent it from stalling, 3494 * but that really is a band-aid. Going forward it should be replaced with 3495 * solutions targeted more specifically at RT tasks. 3496 */ 3497 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) 3498 { 3499 struct update_util_data *data; 3500 3501 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data, 3502 cpu_of(rq))); 3503 if (data) 3504 data->func(data, rq_clock(rq), flags); 3505 } 3506 #else /* !CONFIG_CPU_FREQ: */ 3507 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) { } 3508 #endif /* !CONFIG_CPU_FREQ */ 3509 3510 #ifdef arch_scale_freq_capacity 3511 # ifndef arch_scale_freq_invariant 3512 # define arch_scale_freq_invariant() true 3513 # endif 3514 #else 3515 # define arch_scale_freq_invariant() false 3516 #endif 3517 3518 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs, 3519 unsigned long *min, 3520 unsigned long *max); 3521 3522 unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual, 3523 unsigned long min, 3524 unsigned long max); 3525 3526 3527 /* 3528 * Verify the fitness of task @p to run on @cpu taking into account the 3529 * CPU original capacity and the runtime/deadline ratio of the task. 3530 * 3531 * The function will return true if the original capacity of @cpu is 3532 * greater than or equal to task's deadline density right shifted by 3533 * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise. 3534 */ 3535 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu) 3536 { 3537 unsigned long cap = arch_scale_cpu_capacity(cpu); 3538 3539 return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT); 3540 } 3541 3542 static inline unsigned long cpu_bw_dl(struct rq *rq) 3543 { 3544 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT; 3545 } 3546 3547 static inline unsigned long cpu_util_dl(struct rq *rq) 3548 { 3549 return READ_ONCE(rq->avg_dl.util_avg); 3550 } 3551 3552 3553 extern unsigned long cpu_util_cfs(int cpu); 3554 extern unsigned long cpu_util_cfs_boost(int cpu); 3555 3556 static inline unsigned long cpu_util_rt(struct rq *rq) 3557 { 3558 return READ_ONCE(rq->avg_rt.util_avg); 3559 } 3560 3561 #ifdef CONFIG_UCLAMP_TASK 3562 3563 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id); 3564 3565 /* 3566 * When uclamp is compiled in, the aggregation at rq level is 'turned off' 3567 * by default in the fast path and only gets turned on once userspace performs 3568 * an operation that requires it. 3569 * 3570 * Returns true if userspace opted-in to use uclamp and aggregation at rq level 3571 * hence is active. 3572 */ 3573 static inline bool uclamp_is_used(void) 3574 { 3575 return static_branch_likely(&sched_uclamp_used); 3576 } 3577 3578 /* 3579 * Enabling static branches would get the cpus_read_lock(), 3580 * check whether uclamp_is_used before enable it to avoid always 3581 * calling cpus_read_lock(). Because we never disable this 3582 * static key once enable it. 3583 */ 3584 static inline void sched_uclamp_enable(void) 3585 { 3586 if (!uclamp_is_used()) 3587 static_branch_enable(&sched_uclamp_used); 3588 } 3589 3590 static inline unsigned long uclamp_rq_get(struct rq *rq, 3591 enum uclamp_id clamp_id) 3592 { 3593 return READ_ONCE(rq->uclamp[clamp_id].value); 3594 } 3595 3596 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, 3597 unsigned int value) 3598 { 3599 WRITE_ONCE(rq->uclamp[clamp_id].value, value); 3600 } 3601 3602 static inline bool uclamp_rq_is_idle(struct rq *rq) 3603 { 3604 return rq->uclamp_flags & UCLAMP_FLAG_IDLE; 3605 } 3606 3607 /* Is the rq being capped/throttled by uclamp_max? */ 3608 static inline bool uclamp_rq_is_capped(struct rq *rq) 3609 { 3610 unsigned long rq_util; 3611 unsigned long max_util; 3612 3613 if (!uclamp_is_used()) 3614 return false; 3615 3616 rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq); 3617 max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value); 3618 3619 return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util; 3620 } 3621 3622 #define for_each_clamp_id(clamp_id) \ 3623 for ((clamp_id) = 0; (clamp_id) < UCLAMP_CNT; (clamp_id)++) 3624 3625 extern unsigned int sysctl_sched_uclamp_util_min_rt_default; 3626 3627 3628 static inline unsigned int uclamp_none(enum uclamp_id clamp_id) 3629 { 3630 if (clamp_id == UCLAMP_MIN) 3631 return 0; 3632 return SCHED_CAPACITY_SCALE; 3633 } 3634 3635 /* Integer rounded range for each bucket */ 3636 #define UCLAMP_BUCKET_DELTA DIV_ROUND_CLOSEST(SCHED_CAPACITY_SCALE, UCLAMP_BUCKETS) 3637 3638 static inline unsigned int uclamp_bucket_id(unsigned int clamp_value) 3639 { 3640 return min_t(unsigned int, clamp_value / UCLAMP_BUCKET_DELTA, UCLAMP_BUCKETS - 1); 3641 } 3642 3643 static inline void 3644 uclamp_se_set(struct uclamp_se *uc_se, unsigned int value, bool user_defined) 3645 { 3646 uc_se->value = value; 3647 uc_se->bucket_id = uclamp_bucket_id(value); 3648 uc_se->user_defined = user_defined; 3649 } 3650 3651 #else /* !CONFIG_UCLAMP_TASK: */ 3652 3653 static inline unsigned long 3654 uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id) 3655 { 3656 if (clamp_id == UCLAMP_MIN) 3657 return 0; 3658 3659 return SCHED_CAPACITY_SCALE; 3660 } 3661 3662 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; } 3663 3664 static inline bool uclamp_is_used(void) 3665 { 3666 return false; 3667 } 3668 3669 static inline void sched_uclamp_enable(void) {} 3670 3671 static inline unsigned long 3672 uclamp_rq_get(struct rq *rq, enum uclamp_id clamp_id) 3673 { 3674 if (clamp_id == UCLAMP_MIN) 3675 return 0; 3676 3677 return SCHED_CAPACITY_SCALE; 3678 } 3679 3680 static inline void 3681 uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, unsigned int value) 3682 { 3683 } 3684 3685 static inline bool uclamp_rq_is_idle(struct rq *rq) 3686 { 3687 return false; 3688 } 3689 3690 #endif /* !CONFIG_UCLAMP_TASK */ 3691 3692 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 3693 3694 static inline unsigned long cpu_util_irq(struct rq *rq) 3695 { 3696 return READ_ONCE(rq->avg_irq.util_avg); 3697 } 3698 3699 static inline 3700 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 3701 { 3702 util *= (max - irq); 3703 util /= max; 3704 3705 return util; 3706 3707 } 3708 3709 #else /* !CONFIG_HAVE_SCHED_AVG_IRQ: */ 3710 3711 static inline unsigned long cpu_util_irq(struct rq *rq) 3712 { 3713 return 0; 3714 } 3715 3716 static inline 3717 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 3718 { 3719 return util; 3720 } 3721 3722 #endif /* !CONFIG_HAVE_SCHED_AVG_IRQ */ 3723 3724 extern void __setparam_fair(struct task_struct *p, const struct sched_attr *attr); 3725 3726 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) 3727 3728 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus))) 3729 3730 DECLARE_STATIC_KEY_FALSE(sched_energy_present); 3731 3732 static inline bool sched_energy_enabled(void) 3733 { 3734 return static_branch_unlikely(&sched_energy_present); 3735 } 3736 3737 #else /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL): */ 3738 3739 #define perf_domain_span(pd) NULL 3740 3741 static inline bool sched_energy_enabled(void) { return false; } 3742 3743 #endif /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */ 3744 3745 #ifdef CONFIG_MEMBARRIER 3746 3747 /* 3748 * The scheduler provides memory barriers required by membarrier between: 3749 * - prior user-space memory accesses and store to rq->membarrier_state, 3750 * - store to rq->membarrier_state and following user-space memory accesses. 3751 * In the same way it provides those guarantees around store to rq->curr. 3752 */ 3753 static inline void membarrier_switch_mm(struct rq *rq, 3754 struct mm_struct *prev_mm, 3755 struct mm_struct *next_mm) 3756 { 3757 int membarrier_state; 3758 3759 if (prev_mm == next_mm) 3760 return; 3761 3762 membarrier_state = atomic_read(&next_mm->membarrier_state); 3763 if (READ_ONCE(rq->membarrier_state) == membarrier_state) 3764 return; 3765 3766 WRITE_ONCE(rq->membarrier_state, membarrier_state); 3767 } 3768 3769 #else /* !CONFIG_MEMBARRIER: */ 3770 3771 static inline void membarrier_switch_mm(struct rq *rq, 3772 struct mm_struct *prev_mm, 3773 struct mm_struct *next_mm) 3774 { 3775 } 3776 3777 #endif /* !CONFIG_MEMBARRIER */ 3778 3779 static inline bool is_per_cpu_kthread(struct task_struct *p) 3780 { 3781 if (!(p->flags & PF_KTHREAD)) 3782 return false; 3783 3784 if (p->nr_cpus_allowed != 1) 3785 return false; 3786 3787 return true; 3788 } 3789 3790 extern void swake_up_all_locked(struct swait_queue_head *q); 3791 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait); 3792 3793 extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags); 3794 3795 #ifdef CONFIG_PREEMPT_DYNAMIC 3796 extern int preempt_dynamic_mode; 3797 extern int sched_dynamic_mode(const char *str); 3798 extern void sched_dynamic_update(int mode); 3799 #endif 3800 extern const char *preempt_modes[]; 3801 3802 #ifdef CONFIG_SCHED_MM_CID 3803 3804 static __always_inline bool cid_on_cpu(unsigned int cid) 3805 { 3806 return cid & MM_CID_ONCPU; 3807 } 3808 3809 static __always_inline bool cid_in_transit(unsigned int cid) 3810 { 3811 return cid & MM_CID_TRANSIT; 3812 } 3813 3814 static __always_inline unsigned int cpu_cid_to_cid(unsigned int cid) 3815 { 3816 return cid & ~MM_CID_ONCPU; 3817 } 3818 3819 static __always_inline unsigned int cid_to_cpu_cid(unsigned int cid) 3820 { 3821 return cid | MM_CID_ONCPU; 3822 } 3823 3824 static __always_inline unsigned int cid_to_transit_cid(unsigned int cid) 3825 { 3826 return cid | MM_CID_TRANSIT; 3827 } 3828 3829 static __always_inline unsigned int cid_from_transit_cid(unsigned int cid) 3830 { 3831 return cid & ~MM_CID_TRANSIT; 3832 } 3833 3834 static __always_inline bool cid_on_task(unsigned int cid) 3835 { 3836 /* True if none of the MM_CID_ONCPU, MM_CID_TRANSIT, MM_CID_UNSET bits is set */ 3837 return cid < MM_CID_TRANSIT; 3838 } 3839 3840 static __always_inline void mm_drop_cid(struct mm_struct *mm, unsigned int cid) 3841 { 3842 clear_bit(cid, mm_cidmask(mm)); 3843 } 3844 3845 static __always_inline void mm_unset_cid_on_task(struct task_struct *t) 3846 { 3847 unsigned int cid = t->mm_cid.cid; 3848 3849 t->mm_cid.cid = MM_CID_UNSET; 3850 if (cid_on_task(cid)) 3851 mm_drop_cid(t->mm, cid); 3852 } 3853 3854 static __always_inline void mm_drop_cid_on_cpu(struct mm_struct *mm, struct mm_cid_pcpu *pcp) 3855 { 3856 /* Clear the ONCPU bit, but do not set UNSET in the per CPU storage */ 3857 if (cid_on_cpu(pcp->cid)) { 3858 pcp->cid = cpu_cid_to_cid(pcp->cid); 3859 mm_drop_cid(mm, pcp->cid); 3860 } 3861 } 3862 3863 static inline unsigned int __mm_get_cid(struct mm_struct *mm, unsigned int max_cids) 3864 { 3865 unsigned int cid = find_first_zero_bit(mm_cidmask(mm), max_cids); 3866 3867 if (cid >= max_cids) 3868 return MM_CID_UNSET; 3869 if (test_and_set_bit(cid, mm_cidmask(mm))) 3870 return MM_CID_UNSET; 3871 return cid; 3872 } 3873 3874 static inline unsigned int mm_get_cid(struct mm_struct *mm) 3875 { 3876 unsigned int cid = __mm_get_cid(mm, READ_ONCE(mm->mm_cid.max_cids)); 3877 3878 while (cid == MM_CID_UNSET) { 3879 cpu_relax(); 3880 cid = __mm_get_cid(mm, num_possible_cpus()); 3881 } 3882 return cid; 3883 } 3884 3885 static inline unsigned int mm_cid_converge(struct mm_struct *mm, unsigned int orig_cid, 3886 unsigned int max_cids) 3887 { 3888 unsigned int new_cid, cid = cpu_cid_to_cid(orig_cid); 3889 3890 /* Is it in the optimal CID space? */ 3891 if (likely(cid < max_cids)) 3892 return orig_cid; 3893 3894 /* Try to find one in the optimal space. Otherwise keep the provided. */ 3895 new_cid = __mm_get_cid(mm, max_cids); 3896 if (new_cid != MM_CID_UNSET) { 3897 mm_drop_cid(mm, cid); 3898 /* Preserve the ONCPU mode of the original CID */ 3899 return new_cid | (orig_cid & MM_CID_ONCPU); 3900 } 3901 return orig_cid; 3902 } 3903 3904 static __always_inline void mm_cid_update_task_cid(struct task_struct *t, unsigned int cid) 3905 { 3906 if (t->mm_cid.cid != cid) { 3907 t->mm_cid.cid = cid; 3908 rseq_sched_set_ids_changed(t); 3909 } 3910 } 3911 3912 static __always_inline void mm_cid_update_pcpu_cid(struct mm_struct *mm, unsigned int cid) 3913 { 3914 __this_cpu_write(mm->mm_cid.pcpu->cid, cid); 3915 } 3916 3917 static __always_inline void mm_cid_from_cpu(struct task_struct *t, unsigned int cpu_cid, 3918 unsigned int mode) 3919 { 3920 unsigned int max_cids, tcid = t->mm_cid.cid; 3921 struct mm_struct *mm = t->mm; 3922 3923 max_cids = READ_ONCE(mm->mm_cid.max_cids); 3924 /* Optimize for the common case where both have the ONCPU bit set */ 3925 if (likely(cid_on_cpu(cpu_cid & tcid))) { 3926 if (likely(cpu_cid_to_cid(cpu_cid) < max_cids)) { 3927 mm_cid_update_task_cid(t, cpu_cid); 3928 return; 3929 } 3930 /* Try to converge into the optimal CID space */ 3931 cpu_cid = mm_cid_converge(mm, cpu_cid, max_cids); 3932 } else { 3933 /* Hand over or drop the task owned CID */ 3934 if (cid_on_task(tcid)) { 3935 if (cid_on_cpu(cpu_cid)) 3936 mm_unset_cid_on_task(t); 3937 else 3938 cpu_cid = cid_to_cpu_cid(tcid); 3939 } 3940 /* Still nothing, allocate a new one */ 3941 if (!cid_on_cpu(cpu_cid)) 3942 cpu_cid = cid_to_cpu_cid(mm_get_cid(mm)); 3943 3944 /* Handle the transition mode flag if required */ 3945 if (mode & MM_CID_TRANSIT) 3946 cpu_cid = cpu_cid_to_cid(cpu_cid) | MM_CID_TRANSIT; 3947 } 3948 mm_cid_update_pcpu_cid(mm, cpu_cid); 3949 mm_cid_update_task_cid(t, cpu_cid); 3950 } 3951 3952 static __always_inline void mm_cid_from_task(struct task_struct *t, unsigned int cpu_cid, 3953 unsigned int mode) 3954 { 3955 unsigned int max_cids, tcid = t->mm_cid.cid; 3956 struct mm_struct *mm = t->mm; 3957 3958 max_cids = READ_ONCE(mm->mm_cid.max_cids); 3959 /* Optimize for the common case, where both have the ONCPU bit clear */ 3960 if (likely(cid_on_task(tcid | cpu_cid))) { 3961 if (likely(tcid < max_cids)) { 3962 mm_cid_update_pcpu_cid(mm, tcid); 3963 return; 3964 } 3965 /* Try to converge into the optimal CID space */ 3966 tcid = mm_cid_converge(mm, tcid, max_cids); 3967 } else { 3968 /* Hand over or drop the CPU owned CID */ 3969 if (cid_on_cpu(cpu_cid)) { 3970 if (cid_on_task(tcid)) 3971 mm_drop_cid_on_cpu(mm, this_cpu_ptr(mm->mm_cid.pcpu)); 3972 else 3973 tcid = cpu_cid_to_cid(cpu_cid); 3974 } 3975 /* Still nothing, allocate a new one */ 3976 if (!cid_on_task(tcid)) 3977 tcid = mm_get_cid(mm); 3978 /* Set the transition mode flag if required */ 3979 tcid |= mode & MM_CID_TRANSIT; 3980 } 3981 mm_cid_update_pcpu_cid(mm, tcid); 3982 mm_cid_update_task_cid(t, tcid); 3983 } 3984 3985 static __always_inline void mm_cid_schedin(struct task_struct *next) 3986 { 3987 struct mm_struct *mm = next->mm; 3988 unsigned int cpu_cid, mode; 3989 3990 if (!next->mm_cid.active) 3991 return; 3992 3993 cpu_cid = __this_cpu_read(mm->mm_cid.pcpu->cid); 3994 mode = READ_ONCE(mm->mm_cid.mode); 3995 if (likely(!cid_on_cpu(mode))) 3996 mm_cid_from_task(next, cpu_cid, mode); 3997 else 3998 mm_cid_from_cpu(next, cpu_cid, mode); 3999 } 4000 4001 static __always_inline void mm_cid_schedout(struct task_struct *prev) 4002 { 4003 struct mm_struct *mm = prev->mm; 4004 unsigned int mode, cid; 4005 4006 /* During mode transitions CIDs are temporary and need to be dropped */ 4007 if (likely(!cid_in_transit(prev->mm_cid.cid))) 4008 return; 4009 4010 mode = READ_ONCE(mm->mm_cid.mode); 4011 cid = cid_from_transit_cid(prev->mm_cid.cid); 4012 4013 /* 4014 * If transition mode is done, transfer ownership when the CID is 4015 * within the convergence range to optimize the next schedule in. 4016 */ 4017 if (!cid_in_transit(mode) && cid < READ_ONCE(mm->mm_cid.max_cids)) { 4018 if (cid_on_cpu(mode)) 4019 cid = cid_to_cpu_cid(cid); 4020 4021 /* Update both so that the next schedule in goes into the fast path */ 4022 mm_cid_update_pcpu_cid(mm, cid); 4023 prev->mm_cid.cid = cid; 4024 } else { 4025 mm_drop_cid(mm, cid); 4026 prev->mm_cid.cid = MM_CID_UNSET; 4027 } 4028 } 4029 4030 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next) 4031 { 4032 mm_cid_schedout(prev); 4033 mm_cid_schedin(next); 4034 } 4035 4036 #else /* !CONFIG_SCHED_MM_CID: */ 4037 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next) { } 4038 #endif /* !CONFIG_SCHED_MM_CID */ 4039 4040 extern u64 avg_vruntime(struct cfs_rq *cfs_rq); 4041 extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se); 4042 static inline 4043 void move_queued_task_locked(struct rq *src_rq, struct rq *dst_rq, struct task_struct *task) 4044 { 4045 lockdep_assert_rq_held(src_rq); 4046 lockdep_assert_rq_held(dst_rq); 4047 4048 deactivate_task(src_rq, task, 0); 4049 set_task_cpu(task, dst_rq->cpu); 4050 activate_task(dst_rq, task, 0); 4051 wakeup_preempt(dst_rq, task, 0); 4052 } 4053 4054 static inline 4055 bool task_is_pushable(struct rq *rq, struct task_struct *p, int cpu) 4056 { 4057 if (!task_on_cpu(rq, p) && 4058 cpumask_test_cpu(cpu, &p->cpus_mask)) 4059 return true; 4060 4061 return false; 4062 } 4063 4064 #ifdef CONFIG_RT_MUTEXES 4065 4066 static inline int __rt_effective_prio(struct task_struct *pi_task, int prio) 4067 { 4068 if (pi_task) 4069 prio = min(prio, pi_task->prio); 4070 4071 return prio; 4072 } 4073 4074 static inline int rt_effective_prio(struct task_struct *p, int prio) 4075 { 4076 struct task_struct *pi_task = rt_mutex_get_top_task(p); 4077 4078 return __rt_effective_prio(pi_task, prio); 4079 } 4080 4081 #else /* !CONFIG_RT_MUTEXES: */ 4082 4083 static inline int rt_effective_prio(struct task_struct *p, int prio) 4084 { 4085 return prio; 4086 } 4087 4088 #endif /* !CONFIG_RT_MUTEXES */ 4089 4090 extern int __sched_setscheduler(struct task_struct *p, const struct sched_attr *attr, bool user, bool pi); 4091 extern int __sched_setaffinity(struct task_struct *p, struct affinity_context *ctx); 4092 extern const struct sched_class *__setscheduler_class(int policy, int prio); 4093 extern void set_load_weight(struct task_struct *p, bool update_load); 4094 extern void enqueue_task(struct rq *rq, struct task_struct *p, int flags); 4095 extern bool dequeue_task(struct rq *rq, struct task_struct *p, int flags); 4096 4097 extern struct balance_callback *splice_balance_callbacks(struct rq *rq); 4098 4099 extern void __balance_callbacks(struct rq *rq, struct rq_flags *rf); 4100 extern void balance_callbacks(struct rq *rq, struct balance_callback *head); 4101 4102 /* 4103 * The 'sched_change' pattern is the safe, easy and slow way of changing a 4104 * task's scheduling properties. It dequeues a task, such that the scheduler 4105 * is fully unaware of it; at which point its properties can be modified; 4106 * after which it is enqueued again. 4107 * 4108 * Typically this must be called while holding task_rq_lock, since most/all 4109 * properties are serialized under those locks. There is currently one 4110 * exception to this rule in sched/ext which only holds rq->lock. 4111 */ 4112 4113 /* 4114 * This structure is a temporary, used to preserve/convey the queueing state 4115 * of the task between sched_change_begin() and sched_change_end(). Ensuring 4116 * the task's queueing state is idempotent across the operation. 4117 */ 4118 struct sched_change_ctx { 4119 u64 prio; 4120 struct task_struct *p; 4121 const struct sched_class *class; 4122 int flags; 4123 bool queued; 4124 bool running; 4125 }; 4126 4127 struct sched_change_ctx *sched_change_begin(struct task_struct *p, unsigned int flags); 4128 void sched_change_end(struct sched_change_ctx *ctx); 4129 4130 DEFINE_CLASS(sched_change, struct sched_change_ctx *, 4131 sched_change_end(_T), 4132 sched_change_begin(p, flags), 4133 struct task_struct *p, unsigned int flags) 4134 4135 DEFINE_CLASS_IS_UNCONDITIONAL(sched_change) 4136 4137 #include "ext.h" 4138 4139 #endif /* _KERNEL_SCHED_SCHED_H */ 4140