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_BYPASSING = 1 << 4, 787 SCX_RQ_CLK_VALID = 1 << 5, /* RQ clock is fresh and valid */ 788 SCX_RQ_BAL_CB_PENDING = 1 << 6, /* must queue a cb after dispatching */ 789 790 SCX_RQ_IN_WAKEUP = 1 << 16, 791 SCX_RQ_IN_BALANCE = 1 << 17, 792 }; 793 794 struct scx_rq { 795 struct scx_dispatch_q local_dsq; 796 struct list_head runnable_list; /* runnable tasks on this rq */ 797 struct list_head ddsp_deferred_locals; /* deferred ddsps from enq */ 798 unsigned long ops_qseq; 799 u64 extra_enq_flags; /* see move_task_to_local_dsq() */ 800 u32 nr_running; 801 u32 cpuperf_target; /* [0, SCHED_CAPACITY_SCALE] */ 802 bool cpu_released; 803 u32 flags; 804 u64 clock; /* current per-rq clock -- see scx_bpf_now() */ 805 cpumask_var_t cpus_to_kick; 806 cpumask_var_t cpus_to_kick_if_idle; 807 cpumask_var_t cpus_to_preempt; 808 cpumask_var_t cpus_to_wait; 809 cpumask_var_t cpus_to_sync; 810 bool kick_sync_pending; 811 unsigned long kick_sync; 812 local_t reenq_local_deferred; 813 struct balance_callback deferred_bal_cb; 814 struct balance_callback kick_sync_bal_cb; 815 struct irq_work deferred_irq_work; 816 struct irq_work kick_cpus_irq_work; 817 struct scx_dispatch_q bypass_dsq; 818 }; 819 #endif /* CONFIG_SCHED_CLASS_EXT */ 820 821 static inline int rt_bandwidth_enabled(void) 822 { 823 return sysctl_sched_rt_runtime >= 0; 824 } 825 826 /* RT IPI pull logic requires IRQ_WORK */ 827 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP) 828 # define HAVE_RT_PUSH_IPI 829 #endif 830 831 /* Real-Time classes' related field in a runqueue: */ 832 struct rt_rq { 833 struct rt_prio_array active; 834 unsigned int rt_nr_running; 835 unsigned int rr_nr_running; 836 struct { 837 int curr; /* highest queued rt task prio */ 838 int next; /* next highest */ 839 } highest_prio; 840 bool overloaded; 841 struct plist_head pushable_tasks; 842 843 int rt_queued; 844 845 #ifdef CONFIG_RT_GROUP_SCHED 846 int rt_throttled; 847 u64 rt_time; /* consumed RT time, goes up in update_curr_rt */ 848 u64 rt_runtime; /* allotted RT time, "slice" from rt_bandwidth, RT sharing/balancing */ 849 /* Nests inside the rq lock: */ 850 raw_spinlock_t rt_runtime_lock; 851 852 unsigned int rt_nr_boosted; 853 854 struct rq *rq; /* this is always top-level rq, cache? */ 855 #endif 856 #ifdef CONFIG_CGROUP_SCHED 857 struct task_group *tg; /* this tg has "this" rt_rq on given CPU for runnable entities */ 858 #endif 859 }; 860 861 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq) 862 { 863 return rt_rq->rt_queued && rt_rq->rt_nr_running; 864 } 865 866 /* Deadline class' related fields in a runqueue */ 867 struct dl_rq { 868 /* runqueue is an rbtree, ordered by deadline */ 869 struct rb_root_cached root; 870 871 unsigned int dl_nr_running; 872 873 /* 874 * Deadline values of the currently executing and the 875 * earliest ready task on this rq. Caching these facilitates 876 * the decision whether or not a ready but not running task 877 * should migrate somewhere else. 878 */ 879 struct { 880 u64 curr; 881 u64 next; 882 } earliest_dl; 883 884 bool overloaded; 885 886 /* 887 * Tasks on this rq that can be pushed away. They are kept in 888 * an rb-tree, ordered by tasks' deadlines, with caching 889 * of the leftmost (earliest deadline) element. 890 */ 891 struct rb_root_cached pushable_dl_tasks_root; 892 893 /* 894 * "Active utilization" for this runqueue: increased when a 895 * task wakes up (becomes TASK_RUNNING) and decreased when a 896 * task blocks 897 */ 898 u64 running_bw; 899 900 /* 901 * Utilization of the tasks "assigned" to this runqueue (including 902 * the tasks that are in runqueue and the tasks that executed on this 903 * CPU and blocked). Increased when a task moves to this runqueue, and 904 * decreased when the task moves away (migrates, changes scheduling 905 * policy, or terminates). 906 * This is needed to compute the "inactive utilization" for the 907 * runqueue (inactive utilization = this_bw - running_bw). 908 */ 909 u64 this_bw; 910 u64 extra_bw; 911 912 /* 913 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM 914 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB). 915 */ 916 u64 max_bw; 917 918 /* 919 * Inverse of the fraction of CPU utilization that can be reclaimed 920 * by the GRUB algorithm. 921 */ 922 u64 bw_ratio; 923 }; 924 925 #ifdef CONFIG_FAIR_GROUP_SCHED 926 927 /* An entity is a task if it doesn't "own" a runqueue */ 928 #define entity_is_task(se) (!se->my_q) 929 930 static inline void se_update_runnable(struct sched_entity *se) 931 { 932 if (!entity_is_task(se)) 933 se->runnable_weight = se->my_q->h_nr_runnable; 934 } 935 936 static inline long se_runnable(struct sched_entity *se) 937 { 938 if (se->sched_delayed) 939 return false; 940 941 if (entity_is_task(se)) 942 return !!se->on_rq; 943 else 944 return se->runnable_weight; 945 } 946 947 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 948 949 #define entity_is_task(se) 1 950 951 static inline void se_update_runnable(struct sched_entity *se) { } 952 953 static inline long se_runnable(struct sched_entity *se) 954 { 955 if (se->sched_delayed) 956 return false; 957 958 return !!se->on_rq; 959 } 960 961 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 962 963 /* 964 * XXX we want to get rid of these helpers and use the full load resolution. 965 */ 966 static inline long se_weight(struct sched_entity *se) 967 { 968 return scale_load_down(se->load.weight); 969 } 970 971 972 static inline bool sched_asym_prefer(int a, int b) 973 { 974 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b); 975 } 976 977 struct perf_domain { 978 struct em_perf_domain *em_pd; 979 struct perf_domain *next; 980 struct rcu_head rcu; 981 }; 982 983 /* 984 * We add the notion of a root-domain which will be used to define per-domain 985 * variables. Each exclusive cpuset essentially defines an island domain by 986 * fully partitioning the member CPUs from any other cpuset. Whenever a new 987 * exclusive cpuset is created, we also create and attach a new root-domain 988 * object. 989 * 990 */ 991 struct root_domain { 992 atomic_t refcount; 993 atomic_t rto_count; 994 struct rcu_head rcu; 995 cpumask_var_t span; 996 cpumask_var_t online; 997 998 /* 999 * Indicate pullable load on at least one CPU, e.g: 1000 * - More than one runnable task 1001 * - Running task is misfit 1002 */ 1003 bool overloaded; 1004 1005 /* Indicate one or more CPUs over-utilized (tipping point) */ 1006 bool overutilized; 1007 1008 /* 1009 * The bit corresponding to a CPU gets set here if such CPU has more 1010 * than one runnable -deadline task (as it is below for RT tasks). 1011 */ 1012 cpumask_var_t dlo_mask; 1013 atomic_t dlo_count; 1014 struct dl_bw dl_bw; 1015 struct cpudl cpudl; 1016 1017 /* 1018 * Indicate whether a root_domain's dl_bw has been checked or 1019 * updated. It's monotonously increasing value. 1020 * 1021 * Also, some corner cases, like 'wrap around' is dangerous, but given 1022 * that u64 is 'big enough'. So that shouldn't be a concern. 1023 */ 1024 u64 visit_cookie; 1025 1026 #ifdef HAVE_RT_PUSH_IPI 1027 /* 1028 * For IPI pull requests, loop across the rto_mask. 1029 */ 1030 struct irq_work rto_push_work; 1031 raw_spinlock_t rto_lock; 1032 /* These are only updated and read within rto_lock */ 1033 int rto_loop; 1034 int rto_cpu; 1035 /* These atomics are updated outside of a lock */ 1036 atomic_t rto_loop_next; 1037 atomic_t rto_loop_start; 1038 #endif /* HAVE_RT_PUSH_IPI */ 1039 /* 1040 * The "RT overload" flag: it gets set if a CPU has more than 1041 * one runnable RT task. 1042 */ 1043 cpumask_var_t rto_mask; 1044 struct cpupri cpupri; 1045 1046 /* 1047 * NULL-terminated list of performance domains intersecting with the 1048 * CPUs of the rd. Protected by RCU. 1049 */ 1050 struct perf_domain __rcu *pd; 1051 }; 1052 1053 extern void init_defrootdomain(void); 1054 extern int sched_init_domains(const struct cpumask *cpu_map); 1055 extern void rq_attach_root(struct rq *rq, struct root_domain *rd); 1056 extern void sched_get_rd(struct root_domain *rd); 1057 extern void sched_put_rd(struct root_domain *rd); 1058 1059 static inline int get_rd_overloaded(struct root_domain *rd) 1060 { 1061 return READ_ONCE(rd->overloaded); 1062 } 1063 1064 static inline void set_rd_overloaded(struct root_domain *rd, int status) 1065 { 1066 if (get_rd_overloaded(rd) != status) 1067 WRITE_ONCE(rd->overloaded, status); 1068 } 1069 1070 #ifdef HAVE_RT_PUSH_IPI 1071 extern void rto_push_irq_work_func(struct irq_work *work); 1072 #endif 1073 1074 #ifdef CONFIG_UCLAMP_TASK 1075 /* 1076 * struct uclamp_bucket - Utilization clamp bucket 1077 * @value: utilization clamp value for tasks on this clamp bucket 1078 * @tasks: number of RUNNABLE tasks on this clamp bucket 1079 * 1080 * Keep track of how many tasks are RUNNABLE for a given utilization 1081 * clamp value. 1082 */ 1083 struct uclamp_bucket { 1084 unsigned long value : bits_per(SCHED_CAPACITY_SCALE); 1085 unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE); 1086 }; 1087 1088 /* 1089 * struct uclamp_rq - rq's utilization clamp 1090 * @value: currently active clamp values for a rq 1091 * @bucket: utilization clamp buckets affecting a rq 1092 * 1093 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values. 1094 * A clamp value is affecting a rq when there is at least one task RUNNABLE 1095 * (or actually running) with that value. 1096 * 1097 * There are up to UCLAMP_CNT possible different clamp values, currently there 1098 * are only two: minimum utilization and maximum utilization. 1099 * 1100 * All utilization clamping values are MAX aggregated, since: 1101 * - for util_min: we want to run the CPU at least at the max of the minimum 1102 * utilization required by its currently RUNNABLE tasks. 1103 * - for util_max: we want to allow the CPU to run up to the max of the 1104 * maximum utilization allowed by its currently RUNNABLE tasks. 1105 * 1106 * Since on each system we expect only a limited number of different 1107 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track 1108 * the metrics required to compute all the per-rq utilization clamp values. 1109 */ 1110 struct uclamp_rq { 1111 unsigned int value; 1112 struct uclamp_bucket bucket[UCLAMP_BUCKETS]; 1113 }; 1114 1115 DECLARE_STATIC_KEY_FALSE(sched_uclamp_used); 1116 #endif /* CONFIG_UCLAMP_TASK */ 1117 1118 /* 1119 * This is the main, per-CPU runqueue data structure. 1120 * 1121 * Locking rule: those places that want to lock multiple runqueues 1122 * (such as the load balancing or the thread migration code), lock 1123 * acquire operations must be ordered by ascending &runqueue. 1124 */ 1125 struct rq { 1126 /* 1127 * The following members are loaded together, without holding the 1128 * rq->lock, in an extremely hot loop in update_sg_lb_stats() 1129 * (called from pick_next_task()). To reduce cache pollution from 1130 * this operation, they are placed together on this dedicated cache 1131 * line. Even though some of them are frequently modified, they are 1132 * loaded much more frequently than they are stored. 1133 */ 1134 unsigned int nr_running; 1135 #ifdef CONFIG_NUMA_BALANCING 1136 unsigned int nr_numa_running; 1137 unsigned int nr_preferred_running; 1138 #endif 1139 unsigned int ttwu_pending; 1140 unsigned long cpu_capacity; 1141 #ifdef CONFIG_SCHED_PROXY_EXEC 1142 struct task_struct __rcu *donor; /* Scheduling context */ 1143 struct task_struct __rcu *curr; /* Execution context */ 1144 #else 1145 union { 1146 struct task_struct __rcu *donor; /* Scheduler context */ 1147 struct task_struct __rcu *curr; /* Execution context */ 1148 }; 1149 #endif 1150 struct task_struct *idle; 1151 /* padding left here deliberately */ 1152 1153 /* 1154 * The next cacheline holds the (hot) runqueue lock, as well as 1155 * some other less performance-critical fields. 1156 */ 1157 u64 nr_switches ____cacheline_aligned; 1158 1159 /* runqueue lock: */ 1160 raw_spinlock_t __lock; 1161 1162 #ifdef CONFIG_NO_HZ_COMMON 1163 unsigned int nohz_tick_stopped; 1164 atomic_t nohz_flags; 1165 unsigned int has_blocked_load; 1166 unsigned long last_blocked_load_update_tick; 1167 call_single_data_t nohz_csd; 1168 #endif /* CONFIG_NO_HZ_COMMON */ 1169 1170 #ifdef CONFIG_UCLAMP_TASK 1171 /* Utilization clamp values based on CPU's RUNNABLE tasks */ 1172 struct uclamp_rq uclamp[UCLAMP_CNT] ____cacheline_aligned; 1173 unsigned int uclamp_flags; 1174 #define UCLAMP_FLAG_IDLE 0x01 1175 #endif 1176 1177 struct cfs_rq cfs; 1178 struct rt_rq rt; 1179 struct dl_rq dl; 1180 #ifdef CONFIG_SCHED_CLASS_EXT 1181 struct scx_rq scx; 1182 struct sched_dl_entity ext_server; 1183 #endif 1184 1185 struct sched_dl_entity fair_server; 1186 1187 #ifdef CONFIG_FAIR_GROUP_SCHED 1188 /* list of leaf cfs_rq on this CPU: */ 1189 struct list_head leaf_cfs_rq_list; 1190 struct list_head *tmp_alone_branch; 1191 #endif /* CONFIG_FAIR_GROUP_SCHED */ 1192 1193 #ifdef CONFIG_NUMA_BALANCING 1194 unsigned int numa_migrate_on; 1195 #endif 1196 /* 1197 * This is part of a global counter where only the total sum 1198 * over all CPUs matters. A task can increase this counter on 1199 * one CPU and if it got migrated afterwards it may decrease 1200 * it on another CPU. Always updated under the runqueue lock: 1201 */ 1202 unsigned long nr_uninterruptible; 1203 1204 struct sched_dl_entity *dl_server; 1205 struct task_struct *stop; 1206 const struct sched_class *next_class; 1207 unsigned long next_balance; 1208 struct mm_struct *prev_mm; 1209 1210 /* 1211 * The following fields of clock data are frequently referenced 1212 * and updated together, and should go on their own cache line. 1213 */ 1214 u64 clock_task ____cacheline_aligned; 1215 u64 clock_pelt; 1216 u64 clock; 1217 unsigned long lost_idle_time; 1218 unsigned int clock_update_flags; 1219 u64 clock_pelt_idle; 1220 u64 clock_idle; 1221 1222 #ifndef CONFIG_64BIT 1223 u64 clock_pelt_idle_copy; 1224 u64 clock_idle_copy; 1225 #endif 1226 1227 u64 last_seen_need_resched_ns; 1228 int ticks_without_resched; 1229 1230 #ifdef CONFIG_MEMBARRIER 1231 int membarrier_state; 1232 #endif 1233 1234 struct root_domain *rd; 1235 struct sched_domain __rcu *sd; 1236 1237 struct balance_callback *balance_callback; 1238 1239 unsigned char nohz_idle_balance; 1240 unsigned char idle_balance; 1241 1242 unsigned long misfit_task_load; 1243 1244 /* For active balancing */ 1245 int active_balance; 1246 int push_cpu; 1247 struct cpu_stop_work active_balance_work; 1248 1249 /* CPU of this runqueue: */ 1250 int cpu; 1251 int online; 1252 1253 struct list_head cfs_tasks; 1254 1255 struct sched_avg avg_rt; 1256 struct sched_avg avg_dl; 1257 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 1258 struct sched_avg avg_irq; 1259 #endif 1260 #ifdef CONFIG_SCHED_HW_PRESSURE 1261 struct sched_avg avg_hw; 1262 #endif 1263 u64 idle_stamp; 1264 u64 avg_idle; 1265 1266 /* This is used to determine avg_idle's max value */ 1267 u64 max_idle_balance_cost; 1268 1269 #ifdef CONFIG_HOTPLUG_CPU 1270 struct rcuwait hotplug_wait; 1271 #endif 1272 1273 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 1274 u64 prev_irq_time; 1275 u64 psi_irq_time; 1276 #endif 1277 #ifdef CONFIG_PARAVIRT 1278 u64 prev_steal_time; 1279 #endif 1280 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING 1281 u64 prev_steal_time_rq; 1282 #endif 1283 1284 /* calc_load related fields */ 1285 unsigned long calc_load_update; 1286 long calc_load_active; 1287 1288 #ifdef CONFIG_SCHED_HRTICK 1289 call_single_data_t hrtick_csd; 1290 struct hrtimer hrtick_timer; 1291 ktime_t hrtick_time; 1292 ktime_t hrtick_delay; 1293 unsigned int hrtick_sched; 1294 #endif 1295 1296 #ifdef CONFIG_SCHEDSTATS 1297 /* latency stats */ 1298 struct sched_info rq_sched_info; 1299 unsigned long long rq_cpu_time; 1300 1301 /* sys_sched_yield() stats */ 1302 unsigned int yld_count; 1303 1304 /* schedule() stats */ 1305 unsigned int sched_count; 1306 unsigned int sched_goidle; 1307 1308 /* try_to_wake_up() stats */ 1309 unsigned int ttwu_count; 1310 unsigned int ttwu_local; 1311 #endif 1312 1313 #ifdef CONFIG_CPU_IDLE 1314 /* Must be inspected within a RCU lock section */ 1315 struct cpuidle_state *idle_state; 1316 #endif 1317 1318 unsigned int nr_pinned; 1319 unsigned int push_busy; 1320 struct cpu_stop_work push_work; 1321 1322 #ifdef CONFIG_SCHED_CORE 1323 /* per rq */ 1324 struct rq *core; 1325 struct task_struct *core_pick; 1326 struct sched_dl_entity *core_dl_server; 1327 unsigned int core_enabled; 1328 unsigned int core_sched_seq; 1329 struct rb_root core_tree; 1330 1331 /* shared state -- careful with sched_core_cpu_deactivate() */ 1332 unsigned int core_task_seq; 1333 unsigned int core_pick_seq; 1334 unsigned long core_cookie; 1335 unsigned int core_forceidle_count; 1336 unsigned int core_forceidle_seq; 1337 unsigned int core_forceidle_occupation; 1338 u64 core_forceidle_start; 1339 #endif /* CONFIG_SCHED_CORE */ 1340 1341 /* Scratch cpumask to be temporarily used under rq_lock */ 1342 cpumask_var_t scratch_mask; 1343 1344 #ifdef CONFIG_CFS_BANDWIDTH 1345 call_single_data_t cfsb_csd; 1346 struct list_head cfsb_csd_list; 1347 #endif 1348 1349 atomic_t nr_iowait; 1350 } __no_randomize_layout; 1351 1352 #ifdef CONFIG_FAIR_GROUP_SCHED 1353 1354 /* CPU runqueue to which this cfs_rq is attached */ 1355 static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1356 { 1357 return cfs_rq->rq; 1358 } 1359 1360 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 1361 1362 static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1363 { 1364 return container_of(cfs_rq, struct rq, cfs); 1365 } 1366 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 1367 1368 static inline int cpu_of(struct rq *rq) 1369 { 1370 return rq->cpu; 1371 } 1372 1373 #define MDF_PUSH 0x01 1374 1375 static inline bool is_migration_disabled(struct task_struct *p) 1376 { 1377 return p->migration_disabled; 1378 } 1379 1380 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); 1381 DECLARE_PER_CPU(struct rnd_state, sched_rnd_state); 1382 1383 static inline u32 sched_rng(void) 1384 { 1385 return prandom_u32_state(this_cpu_ptr(&sched_rnd_state)); 1386 } 1387 1388 static __always_inline struct rq *__this_rq(void) 1389 { 1390 return this_cpu_ptr(&runqueues); 1391 } 1392 1393 #define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) 1394 #define this_rq() __this_rq() 1395 #define task_rq(p) cpu_rq(task_cpu(p)) 1396 #define cpu_curr(cpu) (cpu_rq(cpu)->curr) 1397 #define raw_rq() raw_cpu_ptr(&runqueues) 1398 1399 static inline bool idle_rq(struct rq *rq) 1400 { 1401 return rq->curr == rq->idle && !rq->nr_running && !rq->ttwu_pending; 1402 } 1403 1404 /** 1405 * available_idle_cpu - is a given CPU idle for enqueuing work. 1406 * @cpu: the CPU in question. 1407 * 1408 * Return: 1 if the CPU is currently idle. 0 otherwise. 1409 */ 1410 static inline bool available_idle_cpu(int cpu) 1411 { 1412 if (!idle_rq(cpu_rq(cpu))) 1413 return 0; 1414 1415 if (vcpu_is_preempted(cpu)) 1416 return 0; 1417 1418 return 1; 1419 } 1420 1421 #ifdef CONFIG_SCHED_PROXY_EXEC 1422 static inline void rq_set_donor(struct rq *rq, struct task_struct *t) 1423 { 1424 rcu_assign_pointer(rq->donor, t); 1425 } 1426 #else 1427 static inline void rq_set_donor(struct rq *rq, struct task_struct *t) 1428 { 1429 /* Do nothing */ 1430 } 1431 #endif 1432 1433 #ifdef CONFIG_SCHED_CORE 1434 static inline struct cpumask *sched_group_span(struct sched_group *sg); 1435 1436 DECLARE_STATIC_KEY_FALSE(__sched_core_enabled); 1437 1438 static inline bool sched_core_enabled(struct rq *rq) 1439 { 1440 return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled; 1441 } 1442 1443 static inline bool sched_core_disabled(void) 1444 { 1445 return !static_branch_unlikely(&__sched_core_enabled); 1446 } 1447 1448 /* 1449 * Be careful with this function; not for general use. The return value isn't 1450 * stable unless you actually hold a relevant rq->__lock. 1451 */ 1452 static inline raw_spinlock_t *rq_lockp(struct rq *rq) 1453 { 1454 if (sched_core_enabled(rq)) 1455 return &rq->core->__lock; 1456 1457 return &rq->__lock; 1458 } 1459 1460 static inline raw_spinlock_t *__rq_lockp(struct rq *rq) 1461 __returns_ctx_lock(rq_lockp(rq)) /* alias them */ 1462 { 1463 if (rq->core_enabled) 1464 return &rq->core->__lock; 1465 1466 return &rq->__lock; 1467 } 1468 1469 extern bool 1470 cfs_prio_less(const struct task_struct *a, const struct task_struct *b, bool fi); 1471 1472 extern void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi); 1473 1474 /* 1475 * Helpers to check if the CPU's core cookie matches with the task's cookie 1476 * when core scheduling is enabled. 1477 * A special case is that the task's cookie always matches with CPU's core 1478 * cookie if the CPU is in an idle core. 1479 */ 1480 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p) 1481 { 1482 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1483 if (!sched_core_enabled(rq)) 1484 return true; 1485 1486 return rq->core->core_cookie == p->core_cookie; 1487 } 1488 1489 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) 1490 { 1491 bool idle_core = true; 1492 int cpu; 1493 1494 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1495 if (!sched_core_enabled(rq)) 1496 return true; 1497 1498 if (rq->core->core_cookie == p->core_cookie) 1499 return true; 1500 1501 for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) { 1502 if (!available_idle_cpu(cpu)) { 1503 idle_core = false; 1504 break; 1505 } 1506 } 1507 1508 /* 1509 * A CPU in an idle core is always the best choice for tasks with 1510 * cookies. 1511 */ 1512 return idle_core; 1513 } 1514 1515 static inline bool sched_group_cookie_match(struct rq *rq, 1516 struct task_struct *p, 1517 struct sched_group *group) 1518 { 1519 int cpu; 1520 1521 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1522 if (!sched_core_enabled(rq)) 1523 return true; 1524 1525 for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) { 1526 if (sched_core_cookie_match(cpu_rq(cpu), p)) 1527 return true; 1528 } 1529 return false; 1530 } 1531 1532 static inline bool sched_core_enqueued(struct task_struct *p) 1533 { 1534 return !RB_EMPTY_NODE(&p->core_node); 1535 } 1536 1537 extern void sched_core_enqueue(struct rq *rq, struct task_struct *p); 1538 extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags); 1539 1540 extern void sched_core_get(void); 1541 extern void sched_core_put(void); 1542 1543 #else /* !CONFIG_SCHED_CORE: */ 1544 1545 static inline bool sched_core_enabled(struct rq *rq) 1546 { 1547 return false; 1548 } 1549 1550 static inline bool sched_core_disabled(void) 1551 { 1552 return true; 1553 } 1554 1555 static inline raw_spinlock_t *rq_lockp(struct rq *rq) 1556 { 1557 return &rq->__lock; 1558 } 1559 1560 static inline raw_spinlock_t *__rq_lockp(struct rq *rq) 1561 __returns_ctx_lock(rq_lockp(rq)) /* alias them */ 1562 { 1563 return &rq->__lock; 1564 } 1565 1566 static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p) 1567 { 1568 return true; 1569 } 1570 1571 static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) 1572 { 1573 return true; 1574 } 1575 1576 static inline bool sched_group_cookie_match(struct rq *rq, 1577 struct task_struct *p, 1578 struct sched_group *group) 1579 { 1580 return true; 1581 } 1582 1583 #endif /* !CONFIG_SCHED_CORE */ 1584 1585 #ifdef CONFIG_RT_GROUP_SCHED 1586 # ifdef CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED 1587 DECLARE_STATIC_KEY_FALSE(rt_group_sched); 1588 static inline bool rt_group_sched_enabled(void) 1589 { 1590 return static_branch_unlikely(&rt_group_sched); 1591 } 1592 # else /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED: */ 1593 DECLARE_STATIC_KEY_TRUE(rt_group_sched); 1594 static inline bool rt_group_sched_enabled(void) 1595 { 1596 return static_branch_likely(&rt_group_sched); 1597 } 1598 # endif /* !CONFIG_RT_GROUP_SCHED_DEFAULT_DISABLED */ 1599 #else /* !CONFIG_RT_GROUP_SCHED: */ 1600 # define rt_group_sched_enabled() false 1601 #endif /* !CONFIG_RT_GROUP_SCHED */ 1602 1603 static inline void lockdep_assert_rq_held(struct rq *rq) 1604 __assumes_ctx_lock(__rq_lockp(rq)) 1605 { 1606 lockdep_assert_held(__rq_lockp(rq)); 1607 } 1608 1609 extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass) 1610 __acquires(__rq_lockp(rq)); 1611 1612 extern bool raw_spin_rq_trylock(struct rq *rq) 1613 __cond_acquires(true, __rq_lockp(rq)); 1614 1615 static inline void raw_spin_rq_lock(struct rq *rq) 1616 __acquires(__rq_lockp(rq)) 1617 { 1618 raw_spin_rq_lock_nested(rq, 0); 1619 } 1620 1621 static inline void raw_spin_rq_unlock(struct rq *rq) 1622 __releases(__rq_lockp(rq)) 1623 { 1624 raw_spin_unlock(rq_lockp(rq)); 1625 } 1626 1627 static inline void raw_spin_rq_lock_irq(struct rq *rq) 1628 __acquires(__rq_lockp(rq)) 1629 { 1630 local_irq_disable(); 1631 raw_spin_rq_lock(rq); 1632 } 1633 1634 static inline void raw_spin_rq_unlock_irq(struct rq *rq) 1635 __releases(__rq_lockp(rq)) 1636 { 1637 raw_spin_rq_unlock(rq); 1638 local_irq_enable(); 1639 } 1640 1641 static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq) 1642 __acquires(__rq_lockp(rq)) 1643 { 1644 unsigned long flags; 1645 1646 local_irq_save(flags); 1647 raw_spin_rq_lock(rq); 1648 1649 return flags; 1650 } 1651 1652 static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags) 1653 __releases(__rq_lockp(rq)) 1654 { 1655 raw_spin_rq_unlock(rq); 1656 local_irq_restore(flags); 1657 } 1658 1659 #define raw_spin_rq_lock_irqsave(rq, flags) \ 1660 do { \ 1661 flags = _raw_spin_rq_lock_irqsave(rq); \ 1662 } while (0) 1663 1664 #ifdef CONFIG_SCHED_SMT 1665 extern void __update_idle_core(struct rq *rq); 1666 1667 static inline void update_idle_core(struct rq *rq) 1668 { 1669 if (static_branch_unlikely(&sched_smt_present)) 1670 __update_idle_core(rq); 1671 } 1672 1673 #else /* !CONFIG_SCHED_SMT: */ 1674 static inline void update_idle_core(struct rq *rq) { } 1675 #endif /* !CONFIG_SCHED_SMT */ 1676 1677 #ifdef CONFIG_FAIR_GROUP_SCHED 1678 1679 static inline struct task_struct *task_of(struct sched_entity *se) 1680 { 1681 WARN_ON_ONCE(!entity_is_task(se)); 1682 return container_of(se, struct task_struct, se); 1683 } 1684 1685 static inline struct cfs_rq *task_cfs_rq(struct task_struct *p) 1686 { 1687 return p->se.cfs_rq; 1688 } 1689 1690 /* runqueue on which this entity is (to be) queued */ 1691 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se) 1692 { 1693 return se->cfs_rq; 1694 } 1695 1696 /* runqueue "owned" by this group */ 1697 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) 1698 { 1699 return grp->my_q; 1700 } 1701 1702 #else /* !CONFIG_FAIR_GROUP_SCHED: */ 1703 1704 #define task_of(_se) container_of(_se, struct task_struct, se) 1705 1706 static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p) 1707 { 1708 return &task_rq(p)->cfs; 1709 } 1710 1711 static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se) 1712 { 1713 const struct task_struct *p = task_of(se); 1714 struct rq *rq = task_rq(p); 1715 1716 return &rq->cfs; 1717 } 1718 1719 /* runqueue "owned" by this group */ 1720 static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) 1721 { 1722 return NULL; 1723 } 1724 1725 #endif /* !CONFIG_FAIR_GROUP_SCHED */ 1726 1727 extern void update_rq_avg_idle(struct rq *rq); 1728 extern void update_rq_clock(struct rq *rq); 1729 1730 /* 1731 * rq::clock_update_flags bits 1732 * 1733 * %RQCF_REQ_SKIP - will request skipping of clock update on the next 1734 * call to __schedule(). This is an optimisation to avoid 1735 * neighbouring rq clock updates. 1736 * 1737 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is 1738 * in effect and calls to update_rq_clock() are being ignored. 1739 * 1740 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been 1741 * made to update_rq_clock() since the last time rq::lock was pinned. 1742 * 1743 * If inside of __schedule(), clock_update_flags will have been 1744 * shifted left (a left shift is a cheap operation for the fast path 1745 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use, 1746 * 1747 * if (rq-clock_update_flags >= RQCF_UPDATED) 1748 * 1749 * to check if %RQCF_UPDATED is set. It'll never be shifted more than 1750 * one position though, because the next rq_unpin_lock() will shift it 1751 * back. 1752 */ 1753 #define RQCF_REQ_SKIP 0x01 1754 #define RQCF_ACT_SKIP 0x02 1755 #define RQCF_UPDATED 0x04 1756 1757 static inline void assert_clock_updated(struct rq *rq) 1758 { 1759 /* 1760 * The only reason for not seeing a clock update since the 1761 * last rq_pin_lock() is if we're currently skipping updates. 1762 */ 1763 WARN_ON_ONCE(rq->clock_update_flags < RQCF_ACT_SKIP); 1764 } 1765 1766 static inline u64 rq_clock(struct rq *rq) 1767 { 1768 lockdep_assert_rq_held(rq); 1769 assert_clock_updated(rq); 1770 1771 return rq->clock; 1772 } 1773 1774 static inline u64 rq_clock_task(struct rq *rq) 1775 { 1776 lockdep_assert_rq_held(rq); 1777 assert_clock_updated(rq); 1778 1779 return rq->clock_task; 1780 } 1781 1782 static inline void rq_clock_skip_update(struct rq *rq) 1783 { 1784 lockdep_assert_rq_held(rq); 1785 rq->clock_update_flags |= RQCF_REQ_SKIP; 1786 } 1787 1788 /* 1789 * See rt task throttling, which is the only time a skip 1790 * request is canceled. 1791 */ 1792 static inline void rq_clock_cancel_skipupdate(struct rq *rq) 1793 { 1794 lockdep_assert_rq_held(rq); 1795 rq->clock_update_flags &= ~RQCF_REQ_SKIP; 1796 } 1797 1798 /* 1799 * During cpu offlining and rq wide unthrottling, we can trigger 1800 * an update_rq_clock() for several cfs and rt runqueues (Typically 1801 * when using list_for_each_entry_*) 1802 * rq_clock_start_loop_update() can be called after updating the clock 1803 * once and before iterating over the list to prevent multiple update. 1804 * After the iterative traversal, we need to call rq_clock_stop_loop_update() 1805 * to clear RQCF_ACT_SKIP of rq->clock_update_flags. 1806 */ 1807 static inline void rq_clock_start_loop_update(struct rq *rq) 1808 { 1809 lockdep_assert_rq_held(rq); 1810 WARN_ON_ONCE(rq->clock_update_flags & RQCF_ACT_SKIP); 1811 rq->clock_update_flags |= RQCF_ACT_SKIP; 1812 } 1813 1814 static inline void rq_clock_stop_loop_update(struct rq *rq) 1815 { 1816 lockdep_assert_rq_held(rq); 1817 rq->clock_update_flags &= ~RQCF_ACT_SKIP; 1818 } 1819 1820 struct rq_flags { 1821 unsigned long flags; 1822 struct pin_cookie cookie; 1823 /* 1824 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the 1825 * current pin context is stashed here in case it needs to be 1826 * restored in rq_repin_lock(). 1827 */ 1828 unsigned int clock_update_flags; 1829 }; 1830 1831 extern struct balance_callback balance_push_callback; 1832 1833 #ifdef CONFIG_SCHED_CLASS_EXT 1834 extern const struct sched_class ext_sched_class; 1835 1836 DECLARE_STATIC_KEY_FALSE(__scx_enabled); /* SCX BPF scheduler loaded */ 1837 DECLARE_STATIC_KEY_FALSE(__scx_switched_all); /* all fair class tasks on SCX */ 1838 1839 #define scx_enabled() static_branch_unlikely(&__scx_enabled) 1840 #define scx_switched_all() static_branch_unlikely(&__scx_switched_all) 1841 1842 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) 1843 { 1844 if (!scx_enabled()) 1845 return; 1846 WRITE_ONCE(rq->scx.clock, clock); 1847 smp_store_release(&rq->scx.flags, rq->scx.flags | SCX_RQ_CLK_VALID); 1848 } 1849 1850 static inline void scx_rq_clock_invalidate(struct rq *rq) 1851 { 1852 if (!scx_enabled()) 1853 return; 1854 WRITE_ONCE(rq->scx.flags, rq->scx.flags & ~SCX_RQ_CLK_VALID); 1855 } 1856 1857 #else /* !CONFIG_SCHED_CLASS_EXT: */ 1858 #define scx_enabled() false 1859 #define scx_switched_all() false 1860 1861 static inline void scx_rq_clock_update(struct rq *rq, u64 clock) {} 1862 static inline void scx_rq_clock_invalidate(struct rq *rq) {} 1863 #endif /* !CONFIG_SCHED_CLASS_EXT */ 1864 1865 static inline void assert_balance_callbacks_empty(struct rq *rq) 1866 { 1867 WARN_ON_ONCE(IS_ENABLED(CONFIG_PROVE_LOCKING) && 1868 rq->balance_callback && 1869 rq->balance_callback != &balance_push_callback); 1870 } 1871 1872 /* 1873 * Lockdep annotation that avoids accidental unlocks; it's like a 1874 * sticky/continuous lockdep_assert_held(). 1875 * 1876 * This avoids code that has access to 'struct rq *rq' (basically everything in 1877 * the scheduler) from accidentally unlocking the rq if they do not also have a 1878 * copy of the (on-stack) 'struct rq_flags rf'. 1879 * 1880 * Also see Documentation/locking/lockdep-design.rst. 1881 */ 1882 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf) 1883 { 1884 rf->cookie = lockdep_pin_lock(__rq_lockp(rq)); 1885 1886 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 1887 rf->clock_update_flags = 0; 1888 assert_balance_callbacks_empty(rq); 1889 } 1890 1891 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf) 1892 { 1893 if (rq->clock_update_flags > RQCF_ACT_SKIP) 1894 rf->clock_update_flags = RQCF_UPDATED; 1895 1896 scx_rq_clock_invalidate(rq); 1897 lockdep_unpin_lock(__rq_lockp(rq), rf->cookie); 1898 } 1899 1900 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf) 1901 { 1902 lockdep_repin_lock(__rq_lockp(rq), rf->cookie); 1903 1904 /* 1905 * Restore the value we stashed in @rf for this pin context. 1906 */ 1907 rq->clock_update_flags |= rf->clock_update_flags; 1908 } 1909 1910 #define __task_rq_lock(...) __acquire_ret(___task_rq_lock(__VA_ARGS__), __rq_lockp(__ret)) 1911 extern struct rq *___task_rq_lock(struct task_struct *p, struct rq_flags *rf) __acquires_ret; 1912 1913 #define task_rq_lock(...) __acquire_ret(_task_rq_lock(__VA_ARGS__), __rq_lockp(__ret)) 1914 extern struct rq *_task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1915 __acquires(&p->pi_lock) __acquires_ret; 1916 1917 static inline void 1918 __task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) 1919 __releases(__rq_lockp(rq)) 1920 { 1921 rq_unpin_lock(rq, rf); 1922 raw_spin_rq_unlock(rq); 1923 } 1924 1925 static inline void 1926 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) 1927 __releases(__rq_lockp(rq), &p->pi_lock) 1928 { 1929 __task_rq_unlock(rq, p, rf); 1930 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); 1931 } 1932 1933 DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct, 1934 _T->rq = task_rq_lock(_T->lock, &_T->rf), 1935 task_rq_unlock(_T->rq, _T->lock, &_T->rf), 1936 struct rq *rq; struct rq_flags rf) 1937 DECLARE_LOCK_GUARD_1_ATTRS(task_rq_lock, __acquires(_T->pi_lock), __releases((*(struct task_struct **)_T)->pi_lock)) 1938 #define class_task_rq_lock_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(task_rq_lock, _T) 1939 1940 DEFINE_LOCK_GUARD_1(__task_rq_lock, struct task_struct, 1941 _T->rq = __task_rq_lock(_T->lock, &_T->rf), 1942 __task_rq_unlock(_T->rq, _T->lock, &_T->rf), 1943 struct rq *rq; struct rq_flags rf) 1944 1945 static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) 1946 __acquires(__rq_lockp(rq)) 1947 { 1948 raw_spin_rq_lock_irqsave(rq, rf->flags); 1949 rq_pin_lock(rq, rf); 1950 } 1951 1952 static inline void rq_lock_irq(struct rq *rq, struct rq_flags *rf) 1953 __acquires(__rq_lockp(rq)) 1954 { 1955 raw_spin_rq_lock_irq(rq); 1956 rq_pin_lock(rq, rf); 1957 } 1958 1959 static inline void rq_lock(struct rq *rq, struct rq_flags *rf) 1960 __acquires(__rq_lockp(rq)) 1961 { 1962 raw_spin_rq_lock(rq); 1963 rq_pin_lock(rq, rf); 1964 } 1965 1966 static inline void rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf) 1967 __releases(__rq_lockp(rq)) 1968 { 1969 rq_unpin_lock(rq, rf); 1970 raw_spin_rq_unlock_irqrestore(rq, rf->flags); 1971 } 1972 1973 static inline void rq_unlock_irq(struct rq *rq, struct rq_flags *rf) 1974 __releases(__rq_lockp(rq)) 1975 { 1976 rq_unpin_lock(rq, rf); 1977 raw_spin_rq_unlock_irq(rq); 1978 } 1979 1980 static inline void rq_unlock(struct rq *rq, struct rq_flags *rf) 1981 __releases(__rq_lockp(rq)) 1982 { 1983 rq_unpin_lock(rq, rf); 1984 raw_spin_rq_unlock(rq); 1985 } 1986 1987 DEFINE_LOCK_GUARD_1(rq_lock, struct rq, 1988 rq_lock(_T->lock, &_T->rf), 1989 rq_unlock(_T->lock, &_T->rf), 1990 struct rq_flags rf) 1991 1992 DECLARE_LOCK_GUARD_1_ATTRS(rq_lock, __acquires(__rq_lockp(_T)), __releases(__rq_lockp(*(struct rq **)_T))); 1993 #define class_rq_lock_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock, _T) 1994 1995 DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq, 1996 rq_lock_irq(_T->lock, &_T->rf), 1997 rq_unlock_irq(_T->lock, &_T->rf), 1998 struct rq_flags rf) 1999 2000 DECLARE_LOCK_GUARD_1_ATTRS(rq_lock_irq, __acquires(__rq_lockp(_T)), __releases(__rq_lockp(*(struct rq **)_T))); 2001 #define class_rq_lock_irq_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock_irq, _T) 2002 2003 DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq, 2004 rq_lock_irqsave(_T->lock, &_T->rf), 2005 rq_unlock_irqrestore(_T->lock, &_T->rf), 2006 struct rq_flags rf) 2007 2008 DECLARE_LOCK_GUARD_1_ATTRS(rq_lock_irqsave, __acquires(__rq_lockp(_T)), __releases(__rq_lockp(*(struct rq **)_T))); 2009 #define class_rq_lock_irqsave_constructor(_T) WITH_LOCK_GUARD_1_ATTRS(rq_lock_irqsave, _T) 2010 2011 #define this_rq_lock_irq(...) __acquire_ret(_this_rq_lock_irq(__VA_ARGS__), __rq_lockp(__ret)) 2012 static inline struct rq *_this_rq_lock_irq(struct rq_flags *rf) __acquires_ret 2013 { 2014 struct rq *rq; 2015 2016 local_irq_disable(); 2017 rq = this_rq(); 2018 rq_lock(rq, rf); 2019 2020 return rq; 2021 } 2022 2023 #ifdef CONFIG_NUMA 2024 2025 enum numa_topology_type { 2026 NUMA_DIRECT, 2027 NUMA_GLUELESS_MESH, 2028 NUMA_BACKPLANE, 2029 }; 2030 2031 extern enum numa_topology_type sched_numa_topology_type; 2032 extern int sched_max_numa_distance; 2033 extern bool find_numa_distance(int distance); 2034 extern void sched_init_numa(int offline_node); 2035 extern void sched_update_numa(int cpu, bool online); 2036 extern void sched_domains_numa_masks_set(unsigned int cpu); 2037 extern void sched_domains_numa_masks_clear(unsigned int cpu); 2038 extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu); 2039 2040 #else /* !CONFIG_NUMA: */ 2041 2042 static inline void sched_init_numa(int offline_node) { } 2043 static inline void sched_update_numa(int cpu, bool online) { } 2044 static inline void sched_domains_numa_masks_set(unsigned int cpu) { } 2045 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { } 2046 2047 static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu) 2048 { 2049 return nr_cpu_ids; 2050 } 2051 2052 #endif /* !CONFIG_NUMA */ 2053 2054 #ifdef CONFIG_NUMA_BALANCING 2055 2056 /* The regions in numa_faults array from task_struct */ 2057 enum numa_faults_stats { 2058 NUMA_MEM = 0, 2059 NUMA_CPU, 2060 NUMA_MEMBUF, 2061 NUMA_CPUBUF 2062 }; 2063 2064 extern void sched_setnuma(struct task_struct *p, int node); 2065 extern int migrate_task_to(struct task_struct *p, int cpu); 2066 extern int migrate_swap(struct task_struct *p, struct task_struct *t, 2067 int cpu, int scpu); 2068 extern void init_numa_balancing(u64 clone_flags, struct task_struct *p); 2069 2070 #else /* !CONFIG_NUMA_BALANCING: */ 2071 2072 static inline void 2073 init_numa_balancing(u64 clone_flags, struct task_struct *p) 2074 { 2075 } 2076 2077 #endif /* !CONFIG_NUMA_BALANCING */ 2078 2079 static inline void 2080 queue_balance_callback(struct rq *rq, 2081 struct balance_callback *head, 2082 void (*func)(struct rq *rq)) 2083 { 2084 lockdep_assert_rq_held(rq); 2085 2086 /* 2087 * Don't (re)queue an already queued item; nor queue anything when 2088 * balance_push() is active, see the comment with 2089 * balance_push_callback. 2090 */ 2091 if (unlikely(head->next || rq->balance_callback == &balance_push_callback)) 2092 return; 2093 2094 head->func = func; 2095 head->next = rq->balance_callback; 2096 rq->balance_callback = head; 2097 } 2098 2099 #define rcu_dereference_sched_domain(p) \ 2100 rcu_dereference_all_check((p), lockdep_is_held(&sched_domains_mutex)) 2101 2102 /* 2103 * The domain tree (rq->sd) is protected by RCU's quiescent state transition. 2104 * See destroy_sched_domains: call_rcu for details. 2105 * 2106 * The domain tree of any CPU may only be accessed from within 2107 * preempt-disabled sections. 2108 */ 2109 #define for_each_domain(cpu, __sd) \ 2110 for (__sd = rcu_dereference_sched_domain(cpu_rq(cpu)->sd); \ 2111 __sd; __sd = __sd->parent) 2112 2113 /* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */ 2114 #define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) | 2115 static const unsigned int SD_SHARED_CHILD_MASK = 2116 #include <linux/sched/sd_flags.h> 2117 0; 2118 #undef SD_FLAG 2119 2120 /** 2121 * highest_flag_domain - Return highest sched_domain containing flag. 2122 * @cpu: The CPU whose highest level of sched domain is to 2123 * be returned. 2124 * @flag: The flag to check for the highest sched_domain 2125 * for the given CPU. 2126 * 2127 * Returns the highest sched_domain of a CPU which contains @flag. If @flag has 2128 * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag. 2129 */ 2130 static inline struct sched_domain *highest_flag_domain(int cpu, int flag) 2131 { 2132 struct sched_domain *sd, *hsd = NULL; 2133 2134 for_each_domain(cpu, sd) { 2135 if (sd->flags & flag) { 2136 hsd = sd; 2137 continue; 2138 } 2139 2140 /* 2141 * Stop the search if @flag is known to be shared at lower 2142 * levels. It will not be found further up. 2143 */ 2144 if (flag & SD_SHARED_CHILD_MASK) 2145 break; 2146 } 2147 2148 return hsd; 2149 } 2150 2151 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) 2152 { 2153 struct sched_domain *sd; 2154 2155 for_each_domain(cpu, sd) { 2156 if (sd->flags & flag) 2157 break; 2158 } 2159 2160 return sd; 2161 } 2162 2163 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc); 2164 DECLARE_PER_CPU(int, sd_llc_size); 2165 DECLARE_PER_CPU(int, sd_llc_id); 2166 DECLARE_PER_CPU(int, sd_share_id); 2167 DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared); 2168 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa); 2169 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing); 2170 DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity); 2171 2172 extern struct static_key_false sched_asym_cpucapacity; 2173 extern struct static_key_false sched_cluster_active; 2174 2175 static __always_inline bool sched_asym_cpucap_active(void) 2176 { 2177 return static_branch_unlikely(&sched_asym_cpucapacity); 2178 } 2179 2180 struct sched_group_capacity { 2181 atomic_t ref; 2182 /* 2183 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity 2184 * for a single CPU. 2185 */ 2186 unsigned long capacity; 2187 unsigned long min_capacity; /* Min per-CPU capacity in group */ 2188 unsigned long max_capacity; /* Max per-CPU capacity in group */ 2189 unsigned long next_update; 2190 int imbalance; /* XXX unrelated to capacity but shared group state */ 2191 2192 int id; 2193 2194 unsigned long cpumask[]; /* Balance mask */ 2195 }; 2196 2197 struct sched_group { 2198 struct sched_group *next; /* Must be a circular list */ 2199 atomic_t ref; 2200 2201 unsigned int group_weight; 2202 unsigned int cores; 2203 struct sched_group_capacity *sgc; 2204 int asym_prefer_cpu; /* CPU of highest priority in group */ 2205 int flags; 2206 2207 /* 2208 * The CPUs this group covers. 2209 * 2210 * NOTE: this field is variable length. (Allocated dynamically 2211 * by attaching extra space to the end of the structure, 2212 * depending on how many CPUs the kernel has booted up with) 2213 */ 2214 unsigned long cpumask[]; 2215 }; 2216 2217 static inline struct cpumask *sched_group_span(struct sched_group *sg) 2218 { 2219 return to_cpumask(sg->cpumask); 2220 } 2221 2222 /* 2223 * See build_balance_mask(). 2224 */ 2225 static inline struct cpumask *group_balance_mask(struct sched_group *sg) 2226 { 2227 return to_cpumask(sg->sgc->cpumask); 2228 } 2229 2230 extern int group_balance_cpu(struct sched_group *sg); 2231 2232 extern void update_sched_domain_debugfs(void); 2233 extern void dirty_sched_domain_sysctl(int cpu); 2234 2235 extern int sched_update_scaling(void); 2236 2237 static inline const struct cpumask *task_user_cpus(struct task_struct *p) 2238 { 2239 if (!p->user_cpus_ptr) 2240 return cpu_possible_mask; /* &init_task.cpus_mask */ 2241 return p->user_cpus_ptr; 2242 } 2243 2244 #ifdef CONFIG_CGROUP_SCHED 2245 2246 /* 2247 * Return the group to which this tasks belongs. 2248 * 2249 * We cannot use task_css() and friends because the cgroup subsystem 2250 * changes that value before the cgroup_subsys::attach() method is called, 2251 * therefore we cannot pin it and might observe the wrong value. 2252 * 2253 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup 2254 * core changes this before calling sched_move_task(). 2255 * 2256 * Instead we use a 'copy' which is updated from sched_move_task() while 2257 * holding both task_struct::pi_lock and rq::lock. 2258 */ 2259 static inline struct task_group *task_group(struct task_struct *p) 2260 { 2261 return p->sched_task_group; 2262 } 2263 2264 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ 2265 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) 2266 { 2267 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED) 2268 struct task_group *tg = task_group(p); 2269 #endif 2270 2271 #ifdef CONFIG_FAIR_GROUP_SCHED 2272 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]); 2273 p->se.cfs_rq = tg->cfs_rq[cpu]; 2274 p->se.parent = tg->se[cpu]; 2275 p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0; 2276 #endif 2277 2278 #ifdef CONFIG_RT_GROUP_SCHED 2279 /* 2280 * p->rt.rt_rq is NULL initially and it is easier to assign 2281 * root_task_group's rt_rq than switching in rt_rq_of_se() 2282 * Clobbers tg(!) 2283 */ 2284 if (!rt_group_sched_enabled()) 2285 tg = &root_task_group; 2286 p->rt.rt_rq = tg->rt_rq[cpu]; 2287 p->rt.parent = tg->rt_se[cpu]; 2288 #endif /* CONFIG_RT_GROUP_SCHED */ 2289 } 2290 2291 #else /* !CONFIG_CGROUP_SCHED: */ 2292 2293 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } 2294 2295 static inline struct task_group *task_group(struct task_struct *p) 2296 { 2297 return NULL; 2298 } 2299 2300 #endif /* !CONFIG_CGROUP_SCHED */ 2301 2302 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) 2303 { 2304 set_task_rq(p, cpu); 2305 #ifdef CONFIG_SMP 2306 /* 2307 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be 2308 * successfully executed on another CPU. We must ensure that updates of 2309 * per-task data have been completed by this moment. 2310 */ 2311 smp_wmb(); 2312 WRITE_ONCE(task_thread_info(p)->cpu, cpu); 2313 p->wake_cpu = cpu; 2314 rseq_sched_set_ids_changed(p); 2315 #endif /* CONFIG_SMP */ 2316 } 2317 2318 /* 2319 * Tunables: 2320 */ 2321 2322 #define SCHED_FEAT(name, enabled) \ 2323 __SCHED_FEAT_##name , 2324 2325 enum { 2326 #include "features.h" 2327 __SCHED_FEAT_NR, 2328 }; 2329 2330 #undef SCHED_FEAT 2331 2332 /* 2333 * To support run-time toggling of sched features, all the translation units 2334 * (but core.c) reference the sysctl_sched_features defined in core.c. 2335 */ 2336 extern __read_mostly unsigned int sysctl_sched_features; 2337 2338 #ifdef CONFIG_JUMP_LABEL 2339 2340 #define SCHED_FEAT(name, enabled) \ 2341 static __always_inline bool static_branch_##name(struct static_key *key) \ 2342 { \ 2343 return static_key_##enabled(key); \ 2344 } 2345 2346 #include "features.h" 2347 #undef SCHED_FEAT 2348 2349 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR]; 2350 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x])) 2351 2352 #else /* !CONFIG_JUMP_LABEL: */ 2353 2354 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) 2355 2356 #endif /* !CONFIG_JUMP_LABEL */ 2357 2358 extern struct static_key_false sched_numa_balancing; 2359 extern struct static_key_false sched_schedstats; 2360 2361 static inline u64 global_rt_period(void) 2362 { 2363 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC; 2364 } 2365 2366 static inline u64 global_rt_runtime(void) 2367 { 2368 if (sysctl_sched_rt_runtime < 0) 2369 return RUNTIME_INF; 2370 2371 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC; 2372 } 2373 2374 /* 2375 * Is p the current execution context? 2376 */ 2377 static inline int task_current(struct rq *rq, struct task_struct *p) 2378 { 2379 return rq->curr == p; 2380 } 2381 2382 /* 2383 * Is p the current scheduling context? 2384 * 2385 * Note that it might be the current execution context at the same time if 2386 * rq->curr == rq->donor == p. 2387 */ 2388 static inline int task_current_donor(struct rq *rq, struct task_struct *p) 2389 { 2390 return rq->donor == p; 2391 } 2392 2393 static inline bool task_is_blocked(struct task_struct *p) 2394 { 2395 if (!sched_proxy_exec()) 2396 return false; 2397 2398 return !!p->blocked_on; 2399 } 2400 2401 static inline int task_on_cpu(struct rq *rq, struct task_struct *p) 2402 { 2403 return p->on_cpu; 2404 } 2405 2406 static inline int task_on_rq_queued(struct task_struct *p) 2407 { 2408 return READ_ONCE(p->on_rq) == TASK_ON_RQ_QUEUED; 2409 } 2410 2411 static inline int task_on_rq_migrating(struct task_struct *p) 2412 { 2413 return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING; 2414 } 2415 2416 /* Wake flags. The first three directly map to some SD flag value */ 2417 #define WF_EXEC 0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */ 2418 #define WF_FORK 0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */ 2419 #define WF_TTWU 0x08 /* Wakeup; maps to SD_BALANCE_WAKE */ 2420 2421 #define WF_SYNC 0x10 /* Waker goes to sleep after wakeup */ 2422 #define WF_MIGRATED 0x20 /* Internal use, task got migrated */ 2423 #define WF_CURRENT_CPU 0x40 /* Prefer to move the wakee to the current CPU. */ 2424 #define WF_RQ_SELECTED 0x80 /* ->select_task_rq() was called */ 2425 2426 static_assert(WF_EXEC == SD_BALANCE_EXEC); 2427 static_assert(WF_FORK == SD_BALANCE_FORK); 2428 static_assert(WF_TTWU == SD_BALANCE_WAKE); 2429 2430 /* 2431 * To aid in avoiding the subversion of "niceness" due to uneven distribution 2432 * of tasks with abnormal "nice" values across CPUs the contribution that 2433 * each task makes to its run queue's load is weighted according to its 2434 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a 2435 * scaled version of the new time slice allocation that they receive on time 2436 * slice expiry etc. 2437 */ 2438 2439 #define WEIGHT_IDLEPRIO 3 2440 #define WMULT_IDLEPRIO 1431655765 2441 2442 extern const int sched_prio_to_weight[40]; 2443 extern const u32 sched_prio_to_wmult[40]; 2444 2445 /* 2446 * {de,en}queue flags: 2447 * 2448 * SLEEP/WAKEUP - task is no-longer/just-became runnable 2449 * 2450 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks 2451 * are in a known state which allows modification. Such pairs 2452 * should preserve as much state as possible. 2453 * 2454 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location 2455 * in the runqueue. IOW the priority is allowed to change. Callers 2456 * must expect to deal with balance callbacks. 2457 * 2458 * NOCLOCK - skip the update_rq_clock() (avoids double updates) 2459 * 2460 * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE) 2461 * 2462 * DELAYED - de/re-queue a sched_delayed task 2463 * 2464 * CLASS - going to update p->sched_class; makes sched_change call the 2465 * various switch methods. 2466 * 2467 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified) 2468 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline) 2469 * ENQUEUE_MIGRATED - the task was migrated during wakeup 2470 * ENQUEUE_RQ_SELECTED - ->select_task_rq() was called 2471 * 2472 * XXX SAVE/RESTORE in combination with CLASS doesn't really make sense, but 2473 * SCHED_DEADLINE seems to rely on this for now. 2474 */ 2475 2476 #define DEQUEUE_SLEEP 0x0001 /* Matches ENQUEUE_WAKEUP */ 2477 #define DEQUEUE_SAVE 0x0002 /* Matches ENQUEUE_RESTORE */ 2478 #define DEQUEUE_MOVE 0x0004 /* Matches ENQUEUE_MOVE */ 2479 #define DEQUEUE_NOCLOCK 0x0008 /* Matches ENQUEUE_NOCLOCK */ 2480 2481 #define DEQUEUE_MIGRATING 0x0010 /* Matches ENQUEUE_MIGRATING */ 2482 #define DEQUEUE_DELAYED 0x0020 /* Matches ENQUEUE_DELAYED */ 2483 #define DEQUEUE_CLASS 0x0040 /* Matches ENQUEUE_CLASS */ 2484 2485 #define DEQUEUE_SPECIAL 0x00010000 2486 #define DEQUEUE_THROTTLE 0x00020000 2487 2488 #define ENQUEUE_WAKEUP 0x0001 2489 #define ENQUEUE_RESTORE 0x0002 2490 #define ENQUEUE_MOVE 0x0004 2491 #define ENQUEUE_NOCLOCK 0x0008 2492 2493 #define ENQUEUE_MIGRATING 0x0010 2494 #define ENQUEUE_DELAYED 0x0020 2495 #define ENQUEUE_CLASS 0x0040 2496 2497 #define ENQUEUE_HEAD 0x00010000 2498 #define ENQUEUE_REPLENISH 0x00020000 2499 #define ENQUEUE_MIGRATED 0x00040000 2500 #define ENQUEUE_INITIAL 0x00080000 2501 #define ENQUEUE_RQ_SELECTED 0x00100000 2502 2503 #define RETRY_TASK ((void *)-1UL) 2504 2505 struct affinity_context { 2506 const struct cpumask *new_mask; 2507 struct cpumask *user_mask; 2508 unsigned int flags; 2509 }; 2510 2511 extern s64 update_curr_common(struct rq *rq); 2512 2513 struct sched_class { 2514 2515 #ifdef CONFIG_UCLAMP_TASK 2516 int uclamp_enabled; 2517 #endif 2518 2519 /* 2520 * move_queued_task/activate_task/enqueue_task: rq->lock 2521 * ttwu_do_activate/activate_task/enqueue_task: rq->lock 2522 * wake_up_new_task/activate_task/enqueue_task: task_rq_lock 2523 * ttwu_runnable/enqueue_task: task_rq_lock 2524 * proxy_task_current: rq->lock 2525 * sched_change_end 2526 */ 2527 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags); 2528 /* 2529 * move_queued_task/deactivate_task/dequeue_task: rq->lock 2530 * __schedule/block_task/dequeue_task: rq->lock 2531 * proxy_task_current: rq->lock 2532 * wait_task_inactive: task_rq_lock 2533 * sched_change_begin 2534 */ 2535 bool (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags); 2536 2537 /* 2538 * do_sched_yield: rq->lock 2539 */ 2540 void (*yield_task) (struct rq *rq); 2541 /* 2542 * yield_to: rq->lock (double) 2543 */ 2544 bool (*yield_to_task)(struct rq *rq, struct task_struct *p); 2545 2546 /* 2547 * move_queued_task: rq->lock 2548 * __migrate_swap_task: rq->lock 2549 * ttwu_do_activate: rq->lock 2550 * ttwu_runnable: task_rq_lock 2551 * wake_up_new_task: task_rq_lock 2552 */ 2553 void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags); 2554 2555 /* 2556 * schedule/pick_next_task/prev_balance: rq->lock 2557 */ 2558 int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf); 2559 2560 /* 2561 * schedule/pick_next_task: rq->lock 2562 */ 2563 struct task_struct *(*pick_task)(struct rq *rq, struct rq_flags *rf); 2564 /* 2565 * Optional! When implemented pick_next_task() should be equivalent to: 2566 * 2567 * next = pick_task(); 2568 * if (next) { 2569 * put_prev_task(prev); 2570 * set_next_task_first(next); 2571 * } 2572 */ 2573 struct task_struct *(*pick_next_task)(struct rq *rq, struct task_struct *prev, 2574 struct rq_flags *rf); 2575 2576 /* 2577 * sched_change: 2578 * __schedule: rq->lock 2579 */ 2580 void (*put_prev_task)(struct rq *rq, struct task_struct *p, struct task_struct *next); 2581 void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first); 2582 2583 /* 2584 * select_task_rq: p->pi_lock 2585 * sched_exec: p->pi_lock 2586 */ 2587 int (*select_task_rq)(struct task_struct *p, int task_cpu, int flags); 2588 2589 /* 2590 * set_task_cpu: p->pi_lock || rq->lock (ttwu like) 2591 */ 2592 void (*migrate_task_rq)(struct task_struct *p, int new_cpu); 2593 2594 /* 2595 * ttwu_do_activate: rq->lock 2596 * wake_up_new_task: task_rq_lock 2597 */ 2598 void (*task_woken)(struct rq *this_rq, struct task_struct *task); 2599 2600 /* 2601 * do_set_cpus_allowed: task_rq_lock + sched_change 2602 */ 2603 void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx); 2604 2605 /* 2606 * sched_set_rq_{on,off}line: rq->lock 2607 */ 2608 void (*rq_online)(struct rq *rq); 2609 void (*rq_offline)(struct rq *rq); 2610 2611 /* 2612 * push_cpu_stop: p->pi_lock && rq->lock 2613 */ 2614 struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq); 2615 2616 /* 2617 * hrtick: rq->lock 2618 * sched_tick: rq->lock 2619 * sched_tick_remote: rq->lock 2620 */ 2621 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued); 2622 /* 2623 * sched_cgroup_fork: p->pi_lock 2624 */ 2625 void (*task_fork)(struct task_struct *p); 2626 /* 2627 * finish_task_switch: no locks 2628 */ 2629 void (*task_dead)(struct task_struct *p); 2630 2631 /* 2632 * sched_change 2633 */ 2634 void (*switching_from)(struct rq *this_rq, struct task_struct *task); 2635 void (*switched_from) (struct rq *this_rq, struct task_struct *task); 2636 void (*switching_to) (struct rq *this_rq, struct task_struct *task); 2637 void (*switched_to) (struct rq *this_rq, struct task_struct *task); 2638 u64 (*get_prio) (struct rq *this_rq, struct task_struct *task); 2639 void (*prio_changed) (struct rq *this_rq, struct task_struct *task, 2640 u64 oldprio); 2641 2642 /* 2643 * set_load_weight: task_rq_lock + sched_change 2644 * __setscheduler_parms: task_rq_lock + sched_change 2645 */ 2646 void (*reweight_task)(struct rq *this_rq, struct task_struct *task, 2647 const struct load_weight *lw); 2648 2649 /* 2650 * sched_rr_get_interval: task_rq_lock 2651 */ 2652 unsigned int (*get_rr_interval)(struct rq *rq, 2653 struct task_struct *task); 2654 2655 /* 2656 * task_sched_runtime: task_rq_lock 2657 */ 2658 void (*update_curr)(struct rq *rq); 2659 2660 #ifdef CONFIG_FAIR_GROUP_SCHED 2661 /* 2662 * sched_change_group: task_rq_lock + sched_change 2663 */ 2664 void (*task_change_group)(struct task_struct *p); 2665 #endif 2666 2667 #ifdef CONFIG_SCHED_CORE 2668 /* 2669 * pick_next_task: rq->lock 2670 * try_steal_cookie: rq->lock (double) 2671 */ 2672 int (*task_is_throttled)(struct task_struct *p, int cpu); 2673 #endif 2674 }; 2675 2676 static inline void put_prev_task(struct rq *rq, struct task_struct *prev) 2677 { 2678 WARN_ON_ONCE(rq->donor != prev); 2679 prev->sched_class->put_prev_task(rq, prev, NULL); 2680 } 2681 2682 static inline void set_next_task(struct rq *rq, struct task_struct *next) 2683 { 2684 next->sched_class->set_next_task(rq, next, false); 2685 } 2686 2687 static inline void 2688 __put_prev_set_next_dl_server(struct rq *rq, 2689 struct task_struct *prev, 2690 struct task_struct *next) 2691 { 2692 prev->dl_server = NULL; 2693 next->dl_server = rq->dl_server; 2694 rq->dl_server = NULL; 2695 } 2696 2697 static inline void put_prev_set_next_task(struct rq *rq, 2698 struct task_struct *prev, 2699 struct task_struct *next) 2700 { 2701 WARN_ON_ONCE(rq->donor != prev); 2702 2703 __put_prev_set_next_dl_server(rq, prev, next); 2704 2705 if (next == prev) 2706 return; 2707 2708 prev->sched_class->put_prev_task(rq, prev, next); 2709 next->sched_class->set_next_task(rq, next, true); 2710 } 2711 2712 /* 2713 * Helper to define a sched_class instance; each one is placed in a separate 2714 * section which is ordered by the linker script: 2715 * 2716 * include/asm-generic/vmlinux.lds.h 2717 * 2718 * *CAREFUL* they are laid out in *REVERSE* order!!! 2719 * 2720 * Also enforce alignment on the instance, not the type, to guarantee layout. 2721 */ 2722 #define DEFINE_SCHED_CLASS(name) \ 2723 const struct sched_class name##_sched_class \ 2724 __aligned(__alignof__(struct sched_class)) \ 2725 __section("__" #name "_sched_class") 2726 2727 /* Defined in include/asm-generic/vmlinux.lds.h */ 2728 extern struct sched_class __sched_class_highest[]; 2729 extern struct sched_class __sched_class_lowest[]; 2730 2731 extern const struct sched_class stop_sched_class; 2732 extern const struct sched_class dl_sched_class; 2733 extern const struct sched_class rt_sched_class; 2734 extern const struct sched_class fair_sched_class; 2735 extern const struct sched_class idle_sched_class; 2736 2737 /* 2738 * Iterate only active classes. SCX can take over all fair tasks or be 2739 * completely disabled. If the former, skip fair. If the latter, skip SCX. 2740 */ 2741 static inline const struct sched_class *next_active_class(const struct sched_class *class) 2742 { 2743 class++; 2744 #ifdef CONFIG_SCHED_CLASS_EXT 2745 if (scx_switched_all() && class == &fair_sched_class) 2746 class++; 2747 if (!scx_enabled() && class == &ext_sched_class) 2748 class++; 2749 #endif 2750 return class; 2751 } 2752 2753 #define for_class_range(class, _from, _to) \ 2754 for (class = (_from); class < (_to); class++) 2755 2756 #define for_each_class(class) \ 2757 for_class_range(class, __sched_class_highest, __sched_class_lowest) 2758 2759 #define for_active_class_range(class, _from, _to) \ 2760 for (class = (_from); class != (_to); class = next_active_class(class)) 2761 2762 #define for_each_active_class(class) \ 2763 for_active_class_range(class, __sched_class_highest, __sched_class_lowest) 2764 2765 #define sched_class_above(_a, _b) ((_a) < (_b)) 2766 2767 static inline void rq_modified_begin(struct rq *rq, const struct sched_class *class) 2768 { 2769 if (sched_class_above(rq->next_class, class)) 2770 rq->next_class = class; 2771 } 2772 2773 static inline bool rq_modified_above(struct rq *rq, const struct sched_class *class) 2774 { 2775 return sched_class_above(rq->next_class, class); 2776 } 2777 2778 static inline bool sched_stop_runnable(struct rq *rq) 2779 { 2780 return rq->stop && task_on_rq_queued(rq->stop); 2781 } 2782 2783 static inline bool sched_dl_runnable(struct rq *rq) 2784 { 2785 return rq->dl.dl_nr_running > 0; 2786 } 2787 2788 static inline bool sched_rt_runnable(struct rq *rq) 2789 { 2790 return rq->rt.rt_queued > 0; 2791 } 2792 2793 static inline bool sched_fair_runnable(struct rq *rq) 2794 { 2795 return rq->cfs.nr_queued > 0; 2796 } 2797 2798 extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, 2799 struct rq_flags *rf); 2800 extern struct task_struct *pick_task_idle(struct rq *rq, struct rq_flags *rf); 2801 2802 #define SCA_CHECK 0x01 2803 #define SCA_MIGRATE_DISABLE 0x02 2804 #define SCA_MIGRATE_ENABLE 0x04 2805 #define SCA_USER 0x08 2806 2807 extern void update_group_capacity(struct sched_domain *sd, int cpu); 2808 2809 extern void sched_balance_trigger(struct rq *rq); 2810 2811 extern int __set_cpus_allowed_ptr(struct task_struct *p, struct affinity_context *ctx); 2812 extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx); 2813 2814 static inline bool task_allowed_on_cpu(struct task_struct *p, int cpu) 2815 { 2816 /* When not in the task's cpumask, no point in looking further. */ 2817 if (!cpumask_test_cpu(cpu, p->cpus_ptr)) 2818 return false; 2819 2820 /* Can @cpu run a user thread? */ 2821 if (!(p->flags & PF_KTHREAD) && !task_cpu_possible(cpu, p)) 2822 return false; 2823 2824 return true; 2825 } 2826 2827 static inline cpumask_t *alloc_user_cpus_ptr(int node) 2828 { 2829 /* 2830 * See set_cpus_allowed_force() above for the rcu_head usage. 2831 */ 2832 int size = max_t(int, cpumask_size(), sizeof(struct rcu_head)); 2833 2834 return kmalloc_node(size, GFP_KERNEL, node); 2835 } 2836 2837 static inline struct task_struct *get_push_task(struct rq *rq) 2838 { 2839 struct task_struct *p = rq->donor; 2840 2841 lockdep_assert_rq_held(rq); 2842 2843 if (rq->push_busy) 2844 return NULL; 2845 2846 if (p->nr_cpus_allowed == 1) 2847 return NULL; 2848 2849 if (p->migration_disabled) 2850 return NULL; 2851 2852 rq->push_busy = true; 2853 return get_task_struct(p); 2854 } 2855 2856 extern int push_cpu_stop(void *arg); 2857 2858 #ifdef CONFIG_CPU_IDLE 2859 2860 static inline void idle_set_state(struct rq *rq, 2861 struct cpuidle_state *idle_state) 2862 { 2863 rq->idle_state = idle_state; 2864 } 2865 2866 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 2867 { 2868 lockdep_assert(rcu_read_lock_any_held()); 2869 2870 return rq->idle_state; 2871 } 2872 2873 #else /* !CONFIG_CPU_IDLE: */ 2874 2875 static inline void idle_set_state(struct rq *rq, 2876 struct cpuidle_state *idle_state) 2877 { 2878 } 2879 2880 static inline struct cpuidle_state *idle_get_state(struct rq *rq) 2881 { 2882 return NULL; 2883 } 2884 2885 #endif /* !CONFIG_CPU_IDLE */ 2886 2887 extern void schedule_idle(void); 2888 asmlinkage void schedule_user(void); 2889 2890 extern void sysrq_sched_debug_show(void); 2891 extern void sched_init_granularity(void); 2892 extern void update_max_interval(void); 2893 2894 extern void init_sched_dl_class(void); 2895 extern void init_sched_rt_class(void); 2896 extern void init_sched_fair_class(void); 2897 2898 extern void resched_curr(struct rq *rq); 2899 extern void resched_curr_lazy(struct rq *rq); 2900 extern void resched_cpu(int cpu); 2901 2902 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime); 2903 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq); 2904 2905 extern void init_dl_entity(struct sched_dl_entity *dl_se); 2906 2907 extern void init_cfs_throttle_work(struct task_struct *p); 2908 2909 #define BW_SHIFT 20 2910 #define BW_UNIT (1 << BW_SHIFT) 2911 #define RATIO_SHIFT 8 2912 #define MAX_BW_BITS (64 - BW_SHIFT) 2913 #define MAX_BW ((1ULL << MAX_BW_BITS) - 1) 2914 2915 extern u64 to_ratio(u64 period, u64 runtime); 2916 2917 extern void init_entity_runnable_average(struct sched_entity *se); 2918 extern void post_init_entity_util_avg(struct task_struct *p); 2919 2920 #ifdef CONFIG_NO_HZ_FULL 2921 extern bool sched_can_stop_tick(struct rq *rq); 2922 extern int __init sched_tick_offload_init(void); 2923 2924 /* 2925 * Tick may be needed by tasks in the runqueue depending on their policy and 2926 * requirements. If tick is needed, lets send the target an IPI to kick it out of 2927 * nohz mode if necessary. 2928 */ 2929 static inline void sched_update_tick_dependency(struct rq *rq) 2930 { 2931 int cpu = cpu_of(rq); 2932 2933 if (!tick_nohz_full_cpu(cpu)) 2934 return; 2935 2936 if (sched_can_stop_tick(rq)) 2937 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED); 2938 else 2939 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED); 2940 } 2941 #else /* !CONFIG_NO_HZ_FULL: */ 2942 static inline int sched_tick_offload_init(void) { return 0; } 2943 static inline void sched_update_tick_dependency(struct rq *rq) { } 2944 #endif /* !CONFIG_NO_HZ_FULL */ 2945 2946 static inline void add_nr_running(struct rq *rq, unsigned count) 2947 { 2948 unsigned prev_nr = rq->nr_running; 2949 2950 rq->nr_running = prev_nr + count; 2951 if (trace_sched_update_nr_running_tp_enabled()) { 2952 call_trace_sched_update_nr_running(rq, count); 2953 } 2954 2955 if (prev_nr < 2 && rq->nr_running >= 2) 2956 set_rd_overloaded(rq->rd, 1); 2957 2958 sched_update_tick_dependency(rq); 2959 } 2960 2961 static inline void sub_nr_running(struct rq *rq, unsigned count) 2962 { 2963 rq->nr_running -= count; 2964 if (trace_sched_update_nr_running_tp_enabled()) { 2965 call_trace_sched_update_nr_running(rq, -count); 2966 } 2967 2968 /* Check if we still need preemption */ 2969 sched_update_tick_dependency(rq); 2970 } 2971 2972 static inline void __block_task(struct rq *rq, struct task_struct *p) 2973 { 2974 if (p->sched_contributes_to_load) 2975 rq->nr_uninterruptible++; 2976 2977 if (p->in_iowait) { 2978 atomic_inc(&rq->nr_iowait); 2979 delayacct_blkio_start(); 2980 } 2981 2982 ASSERT_EXCLUSIVE_WRITER(p->on_rq); 2983 2984 /* 2985 * The moment this write goes through, ttwu() can swoop in and migrate 2986 * this task, rendering our rq->__lock ineffective. 2987 * 2988 * __schedule() try_to_wake_up() 2989 * LOCK rq->__lock LOCK p->pi_lock 2990 * pick_next_task() 2991 * pick_next_task_fair() 2992 * pick_next_entity() 2993 * dequeue_entities() 2994 * __block_task() 2995 * RELEASE p->on_rq = 0 if (p->on_rq && ...) 2996 * break; 2997 * 2998 * ACQUIRE (after ctrl-dep) 2999 * 3000 * cpu = select_task_rq(); 3001 * set_task_cpu(p, cpu); 3002 * ttwu_queue() 3003 * ttwu_do_activate() 3004 * LOCK rq->__lock 3005 * activate_task() 3006 * STORE p->on_rq = 1 3007 * UNLOCK rq->__lock 3008 * 3009 * Callers must ensure to not reference @p after this -- we no longer 3010 * own it. 3011 */ 3012 smp_store_release(&p->on_rq, 0); 3013 } 3014 3015 extern void activate_task(struct rq *rq, struct task_struct *p, int flags); 3016 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags); 3017 3018 extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags); 3019 3020 /* 3021 * attach_task() -- attach the task detached by detach_task() to its new rq. 3022 */ 3023 static inline void attach_task(struct rq *rq, struct task_struct *p) 3024 { 3025 lockdep_assert_rq_held(rq); 3026 3027 WARN_ON_ONCE(task_rq(p) != rq); 3028 activate_task(rq, p, ENQUEUE_NOCLOCK); 3029 wakeup_preempt(rq, p, 0); 3030 } 3031 3032 /* 3033 * attach_one_task() -- attaches the task returned from detach_one_task() to 3034 * its new rq. 3035 */ 3036 static inline void attach_one_task(struct rq *rq, struct task_struct *p) 3037 { 3038 guard(rq_lock)(rq); 3039 update_rq_clock(rq); 3040 attach_task(rq, p); 3041 } 3042 3043 #ifdef CONFIG_PREEMPT_RT 3044 # define SCHED_NR_MIGRATE_BREAK 8 3045 #else 3046 # define SCHED_NR_MIGRATE_BREAK 32 3047 #endif 3048 3049 extern __read_mostly unsigned int sysctl_sched_nr_migrate; 3050 extern __read_mostly unsigned int sysctl_sched_migration_cost; 3051 3052 extern unsigned int sysctl_sched_base_slice; 3053 3054 extern int sysctl_resched_latency_warn_ms; 3055 extern int sysctl_resched_latency_warn_once; 3056 3057 extern unsigned int sysctl_sched_tunable_scaling; 3058 3059 extern unsigned int sysctl_numa_balancing_scan_delay; 3060 extern unsigned int sysctl_numa_balancing_scan_period_min; 3061 extern unsigned int sysctl_numa_balancing_scan_period_max; 3062 extern unsigned int sysctl_numa_balancing_scan_size; 3063 extern unsigned int sysctl_numa_balancing_hot_threshold; 3064 3065 #ifdef CONFIG_SCHED_HRTICK 3066 3067 /* 3068 * Use hrtick when: 3069 * - enabled by features 3070 * - hrtimer is actually high res 3071 */ 3072 static inline bool hrtick_enabled(struct rq *rq) 3073 { 3074 return cpu_active(cpu_of(rq)) && hrtimer_highres_enabled(); 3075 } 3076 3077 static inline bool hrtick_enabled_fair(struct rq *rq) 3078 { 3079 return sched_feat(HRTICK) && hrtick_enabled(rq); 3080 } 3081 3082 static inline bool hrtick_enabled_dl(struct rq *rq) 3083 { 3084 return sched_feat(HRTICK_DL) && hrtick_enabled(rq); 3085 } 3086 3087 extern void hrtick_start(struct rq *rq, u64 delay); 3088 static inline bool hrtick_active(struct rq *rq) 3089 { 3090 return hrtimer_active(&rq->hrtick_timer); 3091 } 3092 3093 #else /* !CONFIG_SCHED_HRTICK: */ 3094 static inline bool hrtick_enabled_fair(struct rq *rq) { return false; } 3095 static inline bool hrtick_enabled_dl(struct rq *rq) { return false; } 3096 static inline bool hrtick_enabled(struct rq *rq) { return false; } 3097 #endif /* !CONFIG_SCHED_HRTICK */ 3098 3099 #ifndef arch_scale_freq_tick 3100 static __always_inline void arch_scale_freq_tick(void) { } 3101 #endif 3102 3103 #ifndef arch_scale_freq_capacity 3104 /** 3105 * arch_scale_freq_capacity - get the frequency scale factor of a given CPU. 3106 * @cpu: the CPU in question. 3107 * 3108 * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e. 3109 * 3110 * f_curr 3111 * ------ * SCHED_CAPACITY_SCALE 3112 * f_max 3113 */ 3114 static __always_inline 3115 unsigned long arch_scale_freq_capacity(int cpu) 3116 { 3117 return SCHED_CAPACITY_SCALE; 3118 } 3119 #endif 3120 3121 /* 3122 * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to 3123 * acquire rq lock instead of rq_lock(). So at the end of these two functions 3124 * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of 3125 * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning. 3126 */ 3127 static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) 3128 { 3129 rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 3130 rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 3131 } 3132 3133 #define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...) \ 3134 __DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__) \ 3135 static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2) \ 3136 __no_context_analysis \ 3137 { class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t; \ 3138 _lock; return _t; } 3139 #define DECLARE_LOCK_GUARD_2_ATTRS(_name, _lock, _unlock1, _unlock2) \ 3140 static inline class_##_name##_t class_##_name##_constructor(lock_##_name##_t *_T1, \ 3141 lock_##_name##_t *_T2) _lock; \ 3142 static __always_inline void __class_##_name##_cleanup_ctx1(class_##_name##_t **_T1) \ 3143 __no_context_analysis _unlock1 { } \ 3144 static __always_inline void __class_##_name##_cleanup_ctx2(class_##_name##_t **_T2) \ 3145 __no_context_analysis _unlock2 { } 3146 #define WITH_LOCK_GUARD_2_ATTRS(_name, _T1, _T2) \ 3147 class_##_name##_constructor(_T1, _T2), \ 3148 *__UNIQUE_ID(unlock1) __cleanup(__class_##_name##_cleanup_ctx1) = (void *)(_T1),\ 3149 *__UNIQUE_ID(unlock2) __cleanup(__class_##_name##_cleanup_ctx2) = (void *)(_T2) 3150 3151 static inline bool rq_order_less(struct rq *rq1, struct rq *rq2) 3152 { 3153 #ifdef CONFIG_SCHED_CORE 3154 /* 3155 * In order to not have {0,2},{1,3} turn into into an AB-BA, 3156 * order by core-id first and cpu-id second. 3157 * 3158 * Notably: 3159 * 3160 * double_rq_lock(0,3); will take core-0, core-1 lock 3161 * double_rq_lock(1,2); will take core-1, core-0 lock 3162 * 3163 * when only cpu-id is considered. 3164 */ 3165 if (rq1->core->cpu < rq2->core->cpu) 3166 return true; 3167 if (rq1->core->cpu > rq2->core->cpu) 3168 return false; 3169 3170 /* 3171 * __sched_core_flip() relies on SMT having cpu-id lock order. 3172 */ 3173 #endif /* CONFIG_SCHED_CORE */ 3174 return rq1->cpu < rq2->cpu; 3175 } 3176 3177 extern void double_rq_lock(struct rq *rq1, struct rq *rq2) 3178 __acquires(__rq_lockp(rq1), __rq_lockp(rq2)); 3179 3180 #ifdef CONFIG_PREEMPTION 3181 3182 /* 3183 * fair double_lock_balance: Safely acquires both rq->locks in a fair 3184 * way at the expense of forcing extra atomic operations in all 3185 * invocations. This assures that the double_lock is acquired using the 3186 * same underlying policy as the spinlock_t on this architecture, which 3187 * reduces latency compared to the unfair variant below. However, it 3188 * also adds more overhead and therefore may reduce throughput. 3189 */ 3190 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 3191 __must_hold(__rq_lockp(this_rq)) 3192 __acquires(__rq_lockp(busiest)) 3193 { 3194 raw_spin_rq_unlock(this_rq); 3195 double_rq_lock(this_rq, busiest); 3196 3197 return 1; 3198 } 3199 3200 #else /* !CONFIG_PREEMPTION: */ 3201 /* 3202 * Unfair double_lock_balance: Optimizes throughput at the expense of 3203 * latency by eliminating extra atomic operations when the locks are 3204 * already in proper order on entry. This favors lower CPU-ids and will 3205 * grant the double lock to lower CPUs over higher ids under contention, 3206 * regardless of entry order into the function. 3207 */ 3208 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 3209 __must_hold(__rq_lockp(this_rq)) 3210 __acquires(__rq_lockp(busiest)) 3211 { 3212 if (__rq_lockp(this_rq) == __rq_lockp(busiest)) { 3213 __acquire(__rq_lockp(busiest)); /* already held */ 3214 double_rq_clock_clear_update(this_rq, busiest); 3215 return 0; 3216 } 3217 3218 if (likely(raw_spin_rq_trylock(busiest))) { 3219 double_rq_clock_clear_update(this_rq, busiest); 3220 return 0; 3221 } 3222 3223 if (rq_order_less(this_rq, busiest)) { 3224 raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING); 3225 double_rq_clock_clear_update(this_rq, busiest); 3226 return 0; 3227 } 3228 3229 raw_spin_rq_unlock(this_rq); 3230 double_rq_lock(this_rq, busiest); 3231 3232 return 1; 3233 } 3234 3235 #endif /* !CONFIG_PREEMPTION */ 3236 3237 /* 3238 * double_lock_balance - lock the busiest runqueue, this_rq is locked already. 3239 */ 3240 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest) 3241 __must_hold(__rq_lockp(this_rq)) 3242 __acquires(__rq_lockp(busiest)) 3243 { 3244 lockdep_assert_irqs_disabled(); 3245 3246 return _double_lock_balance(this_rq, busiest); 3247 } 3248 3249 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest) 3250 __releases(__rq_lockp(busiest)) 3251 { 3252 if (__rq_lockp(this_rq) != __rq_lockp(busiest)) 3253 raw_spin_rq_unlock(busiest); 3254 else 3255 __release(__rq_lockp(busiest)); /* fake release */ 3256 lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_); 3257 } 3258 3259 static inline void double_lock(spinlock_t *l1, spinlock_t *l2) 3260 __acquires(l1, l2) 3261 { 3262 if (l1 > l2) 3263 swap(l1, l2); 3264 3265 spin_lock(l1); 3266 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 3267 } 3268 3269 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2) 3270 __acquires(l1, l2) 3271 { 3272 if (l1 > l2) 3273 swap(l1, l2); 3274 3275 spin_lock_irq(l1); 3276 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 3277 } 3278 3279 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2) 3280 __acquires(l1, l2) 3281 { 3282 if (l1 > l2) 3283 swap(l1, l2); 3284 3285 raw_spin_lock(l1); 3286 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 3287 } 3288 3289 static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2) 3290 __releases(l1, l2) 3291 { 3292 raw_spin_unlock(l1); 3293 raw_spin_unlock(l2); 3294 } 3295 3296 DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t, 3297 double_raw_lock(_T->lock, _T->lock2), 3298 double_raw_unlock(_T->lock, _T->lock2)) 3299 3300 DECLARE_LOCK_GUARD_2_ATTRS(double_raw_spinlock, 3301 __acquires(_T1, _T2), 3302 __releases(*(raw_spinlock_t **)_T1), 3303 __releases(*(raw_spinlock_t **)_T2)); 3304 #define class_double_raw_spinlock_constructor(_T1, _T2) \ 3305 WITH_LOCK_GUARD_2_ATTRS(double_raw_spinlock, _T1, _T2) 3306 3307 /* 3308 * double_rq_unlock - safely unlock two runqueues 3309 * 3310 * Note this does not restore interrupts like task_rq_unlock, 3311 * you need to do so manually after calling. 3312 */ 3313 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 3314 __releases(__rq_lockp(rq1), __rq_lockp(rq2)) 3315 { 3316 if (__rq_lockp(rq1) != __rq_lockp(rq2)) 3317 raw_spin_rq_unlock(rq2); 3318 else 3319 __release(__rq_lockp(rq2)); /* fake release */ 3320 raw_spin_rq_unlock(rq1); 3321 } 3322 3323 extern void set_rq_online (struct rq *rq); 3324 extern void set_rq_offline(struct rq *rq); 3325 3326 extern bool sched_smp_initialized; 3327 3328 DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq, 3329 double_rq_lock(_T->lock, _T->lock2), 3330 double_rq_unlock(_T->lock, _T->lock2)) 3331 3332 extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq); 3333 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq); 3334 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq); 3335 3336 extern bool sched_debug_verbose; 3337 3338 extern void print_cfs_stats(struct seq_file *m, int cpu); 3339 extern void print_rt_stats(struct seq_file *m, int cpu); 3340 extern void print_dl_stats(struct seq_file *m, int cpu); 3341 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 3342 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq); 3343 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq); 3344 3345 extern void resched_latency_warn(int cpu, u64 latency); 3346 3347 #ifdef CONFIG_NUMA_BALANCING 3348 extern void show_numa_stats(struct task_struct *p, struct seq_file *m); 3349 extern void 3350 print_numa_stats(struct seq_file *m, int node, unsigned long tsf, 3351 unsigned long tpf, unsigned long gsf, unsigned long gpf); 3352 #endif /* CONFIG_NUMA_BALANCING */ 3353 3354 extern void init_cfs_rq(struct cfs_rq *cfs_rq); 3355 extern void init_rt_rq(struct rt_rq *rt_rq); 3356 extern void init_dl_rq(struct dl_rq *dl_rq); 3357 3358 extern void cfs_bandwidth_usage_inc(void); 3359 extern void cfs_bandwidth_usage_dec(void); 3360 3361 #ifdef CONFIG_NO_HZ_COMMON 3362 3363 #define NOHZ_BALANCE_KICK_BIT 0 3364 #define NOHZ_STATS_KICK_BIT 1 3365 #define NOHZ_NEWILB_KICK_BIT 2 3366 #define NOHZ_NEXT_KICK_BIT 3 3367 3368 /* Run sched_balance_domains() */ 3369 #define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT) 3370 /* Update blocked load */ 3371 #define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT) 3372 /* Update blocked load when entering idle */ 3373 #define NOHZ_NEWILB_KICK BIT(NOHZ_NEWILB_KICK_BIT) 3374 /* Update nohz.next_balance */ 3375 #define NOHZ_NEXT_KICK BIT(NOHZ_NEXT_KICK_BIT) 3376 3377 #define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK) 3378 3379 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags) 3380 3381 extern void nohz_balance_exit_idle(struct rq *rq); 3382 #else /* !CONFIG_NO_HZ_COMMON: */ 3383 static inline void nohz_balance_exit_idle(struct rq *rq) { } 3384 #endif /* !CONFIG_NO_HZ_COMMON */ 3385 3386 #ifdef CONFIG_NO_HZ_COMMON 3387 extern void nohz_run_idle_balance(int cpu); 3388 #else 3389 static inline void nohz_run_idle_balance(int cpu) { } 3390 #endif 3391 3392 #include "stats.h" 3393 3394 #if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS) 3395 3396 extern void __sched_core_account_forceidle(struct rq *rq); 3397 3398 static inline void sched_core_account_forceidle(struct rq *rq) 3399 { 3400 if (schedstat_enabled()) 3401 __sched_core_account_forceidle(rq); 3402 } 3403 3404 extern void __sched_core_tick(struct rq *rq); 3405 3406 static inline void sched_core_tick(struct rq *rq) 3407 { 3408 if (sched_core_enabled(rq) && schedstat_enabled()) 3409 __sched_core_tick(rq); 3410 } 3411 3412 #else /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS): */ 3413 3414 static inline void sched_core_account_forceidle(struct rq *rq) { } 3415 3416 static inline void sched_core_tick(struct rq *rq) { } 3417 3418 #endif /* !(CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS) */ 3419 3420 #ifdef CONFIG_IRQ_TIME_ACCOUNTING 3421 3422 struct irqtime { 3423 u64 total; 3424 u64 tick_delta; 3425 u64 irq_start_time; 3426 struct u64_stats_sync sync; 3427 }; 3428 3429 DECLARE_PER_CPU(struct irqtime, cpu_irqtime); 3430 DECLARE_STATIC_KEY_FALSE(sched_clock_irqtime); 3431 3432 static inline int irqtime_enabled(void) 3433 { 3434 return static_branch_likely(&sched_clock_irqtime); 3435 } 3436 3437 /* 3438 * Returns the irqtime minus the softirq time computed by ksoftirqd. 3439 * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime 3440 * and never move forward. 3441 */ 3442 static inline u64 irq_time_read(int cpu) 3443 { 3444 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu); 3445 unsigned int seq; 3446 u64 total; 3447 3448 do { 3449 seq = __u64_stats_fetch_begin(&irqtime->sync); 3450 total = irqtime->total; 3451 } while (__u64_stats_fetch_retry(&irqtime->sync, seq)); 3452 3453 return total; 3454 } 3455 3456 #else /* !CONFIG_IRQ_TIME_ACCOUNTING: */ 3457 3458 static inline int irqtime_enabled(void) 3459 { 3460 return 0; 3461 } 3462 3463 #endif /* !CONFIG_IRQ_TIME_ACCOUNTING */ 3464 3465 #ifdef CONFIG_CPU_FREQ 3466 3467 DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data); 3468 3469 /** 3470 * cpufreq_update_util - Take a note about CPU utilization changes. 3471 * @rq: Runqueue to carry out the update for. 3472 * @flags: Update reason flags. 3473 * 3474 * This function is called by the scheduler on the CPU whose utilization is 3475 * being updated. 3476 * 3477 * It can only be called from RCU-sched read-side critical sections. 3478 * 3479 * The way cpufreq is currently arranged requires it to evaluate the CPU 3480 * performance state (frequency/voltage) on a regular basis to prevent it from 3481 * being stuck in a completely inadequate performance level for too long. 3482 * That is not guaranteed to happen if the updates are only triggered from CFS 3483 * and DL, though, because they may not be coming in if only RT tasks are 3484 * active all the time (or there are RT tasks only). 3485 * 3486 * As a workaround for that issue, this function is called periodically by the 3487 * RT sched class to trigger extra cpufreq updates to prevent it from stalling, 3488 * but that really is a band-aid. Going forward it should be replaced with 3489 * solutions targeted more specifically at RT tasks. 3490 */ 3491 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) 3492 { 3493 struct update_util_data *data; 3494 3495 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data, 3496 cpu_of(rq))); 3497 if (data) 3498 data->func(data, rq_clock(rq), flags); 3499 } 3500 #else /* !CONFIG_CPU_FREQ: */ 3501 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) { } 3502 #endif /* !CONFIG_CPU_FREQ */ 3503 3504 #ifdef arch_scale_freq_capacity 3505 # ifndef arch_scale_freq_invariant 3506 # define arch_scale_freq_invariant() true 3507 # endif 3508 #else 3509 # define arch_scale_freq_invariant() false 3510 #endif 3511 3512 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs, 3513 unsigned long *min, 3514 unsigned long *max); 3515 3516 unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual, 3517 unsigned long min, 3518 unsigned long max); 3519 3520 3521 /* 3522 * Verify the fitness of task @p to run on @cpu taking into account the 3523 * CPU original capacity and the runtime/deadline ratio of the task. 3524 * 3525 * The function will return true if the original capacity of @cpu is 3526 * greater than or equal to task's deadline density right shifted by 3527 * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise. 3528 */ 3529 static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu) 3530 { 3531 unsigned long cap = arch_scale_cpu_capacity(cpu); 3532 3533 return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT); 3534 } 3535 3536 static inline unsigned long cpu_bw_dl(struct rq *rq) 3537 { 3538 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT; 3539 } 3540 3541 static inline unsigned long cpu_util_dl(struct rq *rq) 3542 { 3543 return READ_ONCE(rq->avg_dl.util_avg); 3544 } 3545 3546 3547 extern unsigned long cpu_util_cfs(int cpu); 3548 extern unsigned long cpu_util_cfs_boost(int cpu); 3549 3550 static inline unsigned long cpu_util_rt(struct rq *rq) 3551 { 3552 return READ_ONCE(rq->avg_rt.util_avg); 3553 } 3554 3555 #ifdef CONFIG_UCLAMP_TASK 3556 3557 unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id); 3558 3559 /* 3560 * When uclamp is compiled in, the aggregation at rq level is 'turned off' 3561 * by default in the fast path and only gets turned on once userspace performs 3562 * an operation that requires it. 3563 * 3564 * Returns true if userspace opted-in to use uclamp and aggregation at rq level 3565 * hence is active. 3566 */ 3567 static inline bool uclamp_is_used(void) 3568 { 3569 return static_branch_likely(&sched_uclamp_used); 3570 } 3571 3572 /* 3573 * Enabling static branches would get the cpus_read_lock(), 3574 * check whether uclamp_is_used before enable it to avoid always 3575 * calling cpus_read_lock(). Because we never disable this 3576 * static key once enable it. 3577 */ 3578 static inline void sched_uclamp_enable(void) 3579 { 3580 if (!uclamp_is_used()) 3581 static_branch_enable(&sched_uclamp_used); 3582 } 3583 3584 static inline unsigned long uclamp_rq_get(struct rq *rq, 3585 enum uclamp_id clamp_id) 3586 { 3587 return READ_ONCE(rq->uclamp[clamp_id].value); 3588 } 3589 3590 static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, 3591 unsigned int value) 3592 { 3593 WRITE_ONCE(rq->uclamp[clamp_id].value, value); 3594 } 3595 3596 static inline bool uclamp_rq_is_idle(struct rq *rq) 3597 { 3598 return rq->uclamp_flags & UCLAMP_FLAG_IDLE; 3599 } 3600 3601 /* Is the rq being capped/throttled by uclamp_max? */ 3602 static inline bool uclamp_rq_is_capped(struct rq *rq) 3603 { 3604 unsigned long rq_util; 3605 unsigned long max_util; 3606 3607 if (!uclamp_is_used()) 3608 return false; 3609 3610 rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq); 3611 max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value); 3612 3613 return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util; 3614 } 3615 3616 #define for_each_clamp_id(clamp_id) \ 3617 for ((clamp_id) = 0; (clamp_id) < UCLAMP_CNT; (clamp_id)++) 3618 3619 extern unsigned int sysctl_sched_uclamp_util_min_rt_default; 3620 3621 3622 static inline unsigned int uclamp_none(enum uclamp_id clamp_id) 3623 { 3624 if (clamp_id == UCLAMP_MIN) 3625 return 0; 3626 return SCHED_CAPACITY_SCALE; 3627 } 3628 3629 /* Integer rounded range for each bucket */ 3630 #define UCLAMP_BUCKET_DELTA DIV_ROUND_CLOSEST(SCHED_CAPACITY_SCALE, UCLAMP_BUCKETS) 3631 3632 static inline unsigned int uclamp_bucket_id(unsigned int clamp_value) 3633 { 3634 return min_t(unsigned int, clamp_value / UCLAMP_BUCKET_DELTA, UCLAMP_BUCKETS - 1); 3635 } 3636 3637 static inline void 3638 uclamp_se_set(struct uclamp_se *uc_se, unsigned int value, bool user_defined) 3639 { 3640 uc_se->value = value; 3641 uc_se->bucket_id = uclamp_bucket_id(value); 3642 uc_se->user_defined = user_defined; 3643 } 3644 3645 #else /* !CONFIG_UCLAMP_TASK: */ 3646 3647 static inline unsigned long 3648 uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id) 3649 { 3650 if (clamp_id == UCLAMP_MIN) 3651 return 0; 3652 3653 return SCHED_CAPACITY_SCALE; 3654 } 3655 3656 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; } 3657 3658 static inline bool uclamp_is_used(void) 3659 { 3660 return false; 3661 } 3662 3663 static inline void sched_uclamp_enable(void) {} 3664 3665 static inline unsigned long 3666 uclamp_rq_get(struct rq *rq, enum uclamp_id clamp_id) 3667 { 3668 if (clamp_id == UCLAMP_MIN) 3669 return 0; 3670 3671 return SCHED_CAPACITY_SCALE; 3672 } 3673 3674 static inline void 3675 uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, unsigned int value) 3676 { 3677 } 3678 3679 static inline bool uclamp_rq_is_idle(struct rq *rq) 3680 { 3681 return false; 3682 } 3683 3684 #endif /* !CONFIG_UCLAMP_TASK */ 3685 3686 #ifdef CONFIG_HAVE_SCHED_AVG_IRQ 3687 3688 static inline unsigned long cpu_util_irq(struct rq *rq) 3689 { 3690 return READ_ONCE(rq->avg_irq.util_avg); 3691 } 3692 3693 static inline 3694 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 3695 { 3696 util *= (max - irq); 3697 util /= max; 3698 3699 return util; 3700 3701 } 3702 3703 #else /* !CONFIG_HAVE_SCHED_AVG_IRQ: */ 3704 3705 static inline unsigned long cpu_util_irq(struct rq *rq) 3706 { 3707 return 0; 3708 } 3709 3710 static inline 3711 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 3712 { 3713 return util; 3714 } 3715 3716 #endif /* !CONFIG_HAVE_SCHED_AVG_IRQ */ 3717 3718 extern void __setparam_fair(struct task_struct *p, const struct sched_attr *attr); 3719 3720 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) 3721 3722 #define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus))) 3723 3724 DECLARE_STATIC_KEY_FALSE(sched_energy_present); 3725 3726 static inline bool sched_energy_enabled(void) 3727 { 3728 return static_branch_unlikely(&sched_energy_present); 3729 } 3730 3731 #else /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL): */ 3732 3733 #define perf_domain_span(pd) NULL 3734 3735 static inline bool sched_energy_enabled(void) { return false; } 3736 3737 #endif /* !(CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */ 3738 3739 #ifdef CONFIG_MEMBARRIER 3740 3741 /* 3742 * The scheduler provides memory barriers required by membarrier between: 3743 * - prior user-space memory accesses and store to rq->membarrier_state, 3744 * - store to rq->membarrier_state and following user-space memory accesses. 3745 * In the same way it provides those guarantees around store to rq->curr. 3746 */ 3747 static inline void membarrier_switch_mm(struct rq *rq, 3748 struct mm_struct *prev_mm, 3749 struct mm_struct *next_mm) 3750 { 3751 int membarrier_state; 3752 3753 if (prev_mm == next_mm) 3754 return; 3755 3756 membarrier_state = atomic_read(&next_mm->membarrier_state); 3757 if (READ_ONCE(rq->membarrier_state) == membarrier_state) 3758 return; 3759 3760 WRITE_ONCE(rq->membarrier_state, membarrier_state); 3761 } 3762 3763 #else /* !CONFIG_MEMBARRIER: */ 3764 3765 static inline void membarrier_switch_mm(struct rq *rq, 3766 struct mm_struct *prev_mm, 3767 struct mm_struct *next_mm) 3768 { 3769 } 3770 3771 #endif /* !CONFIG_MEMBARRIER */ 3772 3773 static inline bool is_per_cpu_kthread(struct task_struct *p) 3774 { 3775 if (!(p->flags & PF_KTHREAD)) 3776 return false; 3777 3778 if (p->nr_cpus_allowed != 1) 3779 return false; 3780 3781 return true; 3782 } 3783 3784 extern void swake_up_all_locked(struct swait_queue_head *q); 3785 extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait); 3786 3787 extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags); 3788 3789 #ifdef CONFIG_PREEMPT_DYNAMIC 3790 extern int preempt_dynamic_mode; 3791 extern int sched_dynamic_mode(const char *str); 3792 extern void sched_dynamic_update(int mode); 3793 #endif 3794 extern const char *preempt_modes[]; 3795 3796 #ifdef CONFIG_SCHED_MM_CID 3797 3798 static __always_inline bool cid_on_cpu(unsigned int cid) 3799 { 3800 return cid & MM_CID_ONCPU; 3801 } 3802 3803 static __always_inline bool cid_in_transit(unsigned int cid) 3804 { 3805 return cid & MM_CID_TRANSIT; 3806 } 3807 3808 static __always_inline unsigned int cpu_cid_to_cid(unsigned int cid) 3809 { 3810 return cid & ~MM_CID_ONCPU; 3811 } 3812 3813 static __always_inline unsigned int cid_to_cpu_cid(unsigned int cid) 3814 { 3815 return cid | MM_CID_ONCPU; 3816 } 3817 3818 static __always_inline unsigned int cid_to_transit_cid(unsigned int cid) 3819 { 3820 return cid | MM_CID_TRANSIT; 3821 } 3822 3823 static __always_inline unsigned int cid_from_transit_cid(unsigned int cid) 3824 { 3825 return cid & ~MM_CID_TRANSIT; 3826 } 3827 3828 static __always_inline bool cid_on_task(unsigned int cid) 3829 { 3830 /* True if none of the MM_CID_ONCPU, MM_CID_TRANSIT, MM_CID_UNSET bits is set */ 3831 return cid < MM_CID_TRANSIT; 3832 } 3833 3834 static __always_inline void mm_drop_cid(struct mm_struct *mm, unsigned int cid) 3835 { 3836 clear_bit(cid, mm_cidmask(mm)); 3837 } 3838 3839 static __always_inline void mm_unset_cid_on_task(struct task_struct *t) 3840 { 3841 unsigned int cid = t->mm_cid.cid; 3842 3843 t->mm_cid.cid = MM_CID_UNSET; 3844 if (cid_on_task(cid)) 3845 mm_drop_cid(t->mm, cid); 3846 } 3847 3848 static __always_inline void mm_drop_cid_on_cpu(struct mm_struct *mm, struct mm_cid_pcpu *pcp) 3849 { 3850 /* Clear the ONCPU bit, but do not set UNSET in the per CPU storage */ 3851 if (cid_on_cpu(pcp->cid)) { 3852 pcp->cid = cpu_cid_to_cid(pcp->cid); 3853 mm_drop_cid(mm, pcp->cid); 3854 } 3855 } 3856 3857 static inline unsigned int __mm_get_cid(struct mm_struct *mm, unsigned int max_cids) 3858 { 3859 unsigned int cid = find_first_zero_bit(mm_cidmask(mm), max_cids); 3860 3861 if (cid >= max_cids) 3862 return MM_CID_UNSET; 3863 if (test_and_set_bit(cid, mm_cidmask(mm))) 3864 return MM_CID_UNSET; 3865 return cid; 3866 } 3867 3868 static inline unsigned int mm_get_cid(struct mm_struct *mm) 3869 { 3870 unsigned int cid = __mm_get_cid(mm, READ_ONCE(mm->mm_cid.max_cids)); 3871 3872 while (cid == MM_CID_UNSET) { 3873 cpu_relax(); 3874 cid = __mm_get_cid(mm, num_possible_cpus()); 3875 } 3876 return cid; 3877 } 3878 3879 static inline unsigned int mm_cid_converge(struct mm_struct *mm, unsigned int orig_cid, 3880 unsigned int max_cids) 3881 { 3882 unsigned int new_cid, cid = cpu_cid_to_cid(orig_cid); 3883 3884 /* Is it in the optimal CID space? */ 3885 if (likely(cid < max_cids)) 3886 return orig_cid; 3887 3888 /* Try to find one in the optimal space. Otherwise keep the provided. */ 3889 new_cid = __mm_get_cid(mm, max_cids); 3890 if (new_cid != MM_CID_UNSET) { 3891 mm_drop_cid(mm, cid); 3892 /* Preserve the ONCPU mode of the original CID */ 3893 return new_cid | (orig_cid & MM_CID_ONCPU); 3894 } 3895 return orig_cid; 3896 } 3897 3898 static __always_inline void mm_cid_update_task_cid(struct task_struct *t, unsigned int cid) 3899 { 3900 if (t->mm_cid.cid != cid) { 3901 t->mm_cid.cid = cid; 3902 rseq_sched_set_ids_changed(t); 3903 } 3904 } 3905 3906 static __always_inline void mm_cid_update_pcpu_cid(struct mm_struct *mm, unsigned int cid) 3907 { 3908 __this_cpu_write(mm->mm_cid.pcpu->cid, cid); 3909 } 3910 3911 static __always_inline void mm_cid_from_cpu(struct task_struct *t, unsigned int cpu_cid, 3912 unsigned int mode) 3913 { 3914 unsigned int max_cids, tcid = t->mm_cid.cid; 3915 struct mm_struct *mm = t->mm; 3916 3917 max_cids = READ_ONCE(mm->mm_cid.max_cids); 3918 /* Optimize for the common case where both have the ONCPU bit set */ 3919 if (likely(cid_on_cpu(cpu_cid & tcid))) { 3920 if (likely(cpu_cid_to_cid(cpu_cid) < max_cids)) { 3921 mm_cid_update_task_cid(t, cpu_cid); 3922 return; 3923 } 3924 /* Try to converge into the optimal CID space */ 3925 cpu_cid = mm_cid_converge(mm, cpu_cid, max_cids); 3926 } else { 3927 /* Hand over or drop the task owned CID */ 3928 if (cid_on_task(tcid)) { 3929 if (cid_on_cpu(cpu_cid)) 3930 mm_unset_cid_on_task(t); 3931 else 3932 cpu_cid = cid_to_cpu_cid(tcid); 3933 } 3934 /* Still nothing, allocate a new one */ 3935 if (!cid_on_cpu(cpu_cid)) 3936 cpu_cid = cid_to_cpu_cid(mm_get_cid(mm)); 3937 3938 /* Handle the transition mode flag if required */ 3939 if (mode & MM_CID_TRANSIT) 3940 cpu_cid = cpu_cid_to_cid(cpu_cid) | MM_CID_TRANSIT; 3941 } 3942 mm_cid_update_pcpu_cid(mm, cpu_cid); 3943 mm_cid_update_task_cid(t, cpu_cid); 3944 } 3945 3946 static __always_inline void mm_cid_from_task(struct task_struct *t, unsigned int cpu_cid, 3947 unsigned int mode) 3948 { 3949 unsigned int max_cids, tcid = t->mm_cid.cid; 3950 struct mm_struct *mm = t->mm; 3951 3952 max_cids = READ_ONCE(mm->mm_cid.max_cids); 3953 /* Optimize for the common case, where both have the ONCPU bit clear */ 3954 if (likely(cid_on_task(tcid | cpu_cid))) { 3955 if (likely(tcid < max_cids)) { 3956 mm_cid_update_pcpu_cid(mm, tcid); 3957 return; 3958 } 3959 /* Try to converge into the optimal CID space */ 3960 tcid = mm_cid_converge(mm, tcid, max_cids); 3961 } else { 3962 /* Hand over or drop the CPU owned CID */ 3963 if (cid_on_cpu(cpu_cid)) { 3964 if (cid_on_task(tcid)) 3965 mm_drop_cid_on_cpu(mm, this_cpu_ptr(mm->mm_cid.pcpu)); 3966 else 3967 tcid = cpu_cid_to_cid(cpu_cid); 3968 } 3969 /* Still nothing, allocate a new one */ 3970 if (!cid_on_task(tcid)) 3971 tcid = mm_get_cid(mm); 3972 /* Set the transition mode flag if required */ 3973 tcid |= mode & MM_CID_TRANSIT; 3974 } 3975 mm_cid_update_pcpu_cid(mm, tcid); 3976 mm_cid_update_task_cid(t, tcid); 3977 } 3978 3979 static __always_inline void mm_cid_schedin(struct task_struct *next) 3980 { 3981 struct mm_struct *mm = next->mm; 3982 unsigned int cpu_cid, mode; 3983 3984 if (!next->mm_cid.active) 3985 return; 3986 3987 cpu_cid = __this_cpu_read(mm->mm_cid.pcpu->cid); 3988 mode = READ_ONCE(mm->mm_cid.mode); 3989 if (likely(!cid_on_cpu(mode))) 3990 mm_cid_from_task(next, cpu_cid, mode); 3991 else 3992 mm_cid_from_cpu(next, cpu_cid, mode); 3993 } 3994 3995 static __always_inline void mm_cid_schedout(struct task_struct *prev) 3996 { 3997 struct mm_struct *mm = prev->mm; 3998 unsigned int mode, cid; 3999 4000 /* During mode transitions CIDs are temporary and need to be dropped */ 4001 if (likely(!cid_in_transit(prev->mm_cid.cid))) 4002 return; 4003 4004 mode = READ_ONCE(mm->mm_cid.mode); 4005 cid = cid_from_transit_cid(prev->mm_cid.cid); 4006 4007 /* 4008 * If transition mode is done, transfer ownership when the CID is 4009 * within the convergence range to optimize the next schedule in. 4010 */ 4011 if (!cid_in_transit(mode) && cid < READ_ONCE(mm->mm_cid.max_cids)) { 4012 if (cid_on_cpu(mode)) 4013 cid = cid_to_cpu_cid(cid); 4014 4015 /* Update both so that the next schedule in goes into the fast path */ 4016 mm_cid_update_pcpu_cid(mm, cid); 4017 prev->mm_cid.cid = cid; 4018 } else { 4019 mm_drop_cid(mm, cid); 4020 prev->mm_cid.cid = MM_CID_UNSET; 4021 } 4022 } 4023 4024 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next) 4025 { 4026 mm_cid_schedout(prev); 4027 mm_cid_schedin(next); 4028 } 4029 4030 #else /* !CONFIG_SCHED_MM_CID: */ 4031 static inline void mm_cid_switch_to(struct task_struct *prev, struct task_struct *next) { } 4032 #endif /* !CONFIG_SCHED_MM_CID */ 4033 4034 extern u64 avg_vruntime(struct cfs_rq *cfs_rq); 4035 extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se); 4036 static inline 4037 void move_queued_task_locked(struct rq *src_rq, struct rq *dst_rq, struct task_struct *task) 4038 { 4039 lockdep_assert_rq_held(src_rq); 4040 lockdep_assert_rq_held(dst_rq); 4041 4042 deactivate_task(src_rq, task, 0); 4043 set_task_cpu(task, dst_rq->cpu); 4044 activate_task(dst_rq, task, 0); 4045 wakeup_preempt(dst_rq, task, 0); 4046 } 4047 4048 static inline 4049 bool task_is_pushable(struct rq *rq, struct task_struct *p, int cpu) 4050 { 4051 if (!task_on_cpu(rq, p) && 4052 cpumask_test_cpu(cpu, &p->cpus_mask)) 4053 return true; 4054 4055 return false; 4056 } 4057 4058 #ifdef CONFIG_RT_MUTEXES 4059 4060 static inline int __rt_effective_prio(struct task_struct *pi_task, int prio) 4061 { 4062 if (pi_task) 4063 prio = min(prio, pi_task->prio); 4064 4065 return prio; 4066 } 4067 4068 static inline int rt_effective_prio(struct task_struct *p, int prio) 4069 { 4070 struct task_struct *pi_task = rt_mutex_get_top_task(p); 4071 4072 return __rt_effective_prio(pi_task, prio); 4073 } 4074 4075 #else /* !CONFIG_RT_MUTEXES: */ 4076 4077 static inline int rt_effective_prio(struct task_struct *p, int prio) 4078 { 4079 return prio; 4080 } 4081 4082 #endif /* !CONFIG_RT_MUTEXES */ 4083 4084 extern int __sched_setscheduler(struct task_struct *p, const struct sched_attr *attr, bool user, bool pi); 4085 extern int __sched_setaffinity(struct task_struct *p, struct affinity_context *ctx); 4086 extern const struct sched_class *__setscheduler_class(int policy, int prio); 4087 extern void set_load_weight(struct task_struct *p, bool update_load); 4088 extern void enqueue_task(struct rq *rq, struct task_struct *p, int flags); 4089 extern bool dequeue_task(struct rq *rq, struct task_struct *p, int flags); 4090 4091 extern struct balance_callback *splice_balance_callbacks(struct rq *rq); 4092 4093 extern void __balance_callbacks(struct rq *rq, struct rq_flags *rf); 4094 extern void balance_callbacks(struct rq *rq, struct balance_callback *head); 4095 4096 /* 4097 * The 'sched_change' pattern is the safe, easy and slow way of changing a 4098 * task's scheduling properties. It dequeues a task, such that the scheduler 4099 * is fully unaware of it; at which point its properties can be modified; 4100 * after which it is enqueued again. 4101 * 4102 * Typically this must be called while holding task_rq_lock, since most/all 4103 * properties are serialized under those locks. There is currently one 4104 * exception to this rule in sched/ext which only holds rq->lock. 4105 */ 4106 4107 /* 4108 * This structure is a temporary, used to preserve/convey the queueing state 4109 * of the task between sched_change_begin() and sched_change_end(). Ensuring 4110 * the task's queueing state is idempotent across the operation. 4111 */ 4112 struct sched_change_ctx { 4113 u64 prio; 4114 struct task_struct *p; 4115 const struct sched_class *class; 4116 int flags; 4117 bool queued; 4118 bool running; 4119 }; 4120 4121 struct sched_change_ctx *sched_change_begin(struct task_struct *p, unsigned int flags); 4122 void sched_change_end(struct sched_change_ctx *ctx); 4123 4124 DEFINE_CLASS(sched_change, struct sched_change_ctx *, 4125 sched_change_end(_T), 4126 sched_change_begin(p, flags), 4127 struct task_struct *p, unsigned int flags) 4128 4129 DEFINE_CLASS_IS_UNCONDITIONAL(sched_change) 4130 4131 #include "ext.h" 4132 4133 #endif /* _KERNEL_SCHED_SCHED_H */ 4134