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/sched/affinity.h> 9#include <linux/sched/autogroup.h> 10#include <linux/sched/cpufreq.h> 11#include <linux/sched/deadline.h> 12#include <linux/sched.h> 13#include <linux/sched/loadavg.h> 14#include <linux/sched/mm.h> 15#include <linux/sched/rseq_api.h> 16#include <linux/sched/signal.h> 17#include <linux/sched/smt.h> 18#include <linux/sched/stat.h> 19#include <linux/sched/sysctl.h> 20#include <linux/sched/task_flags.h> 21#include <linux/sched/task.h> 22#include <linux/sched/topology.h> 23 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/ctype.h> 34#include <linux/file.h> 35#include <linux/fs_api.h> 36#include <linux/hrtimer_api.h> 37#include <linux/interrupt.h> 38#include <linux/irq_work.h> 39#include <linux/jiffies.h> 40#include <linux/kref_api.h> 41#include <linux/kthread.h> 42#include <linux/ktime_api.h> 43#include <linux/lockdep_api.h> 44#include <linux/lockdep.h> 45#include <linux/minmax.h> 46#include <linux/mm.h> 47#include <linux/module.h> 48#include <linux/mutex_api.h> 49#include <linux/plist.h> 50#include <linux/poll.h> 51#include <linux/proc_fs.h> 52#include <linux/profile.h> 53#include <linux/psi.h> 54#include <linux/rcupdate.h> 55#include <linux/seq_file.h> 56#include <linux/seqlock.h> 57#include <linux/softirq.h> 58#include <linux/spinlock_api.h> 59#include <linux/static_key.h> 60#include <linux/stop_machine.h> 61#include <linux/syscalls_api.h> 62#include <linux/syscalls.h> 63#include <linux/tick.h> 64#include <linux/topology.h> 65#include <linux/types.h> 66#include <linux/u64_stats_sync_api.h> 67#include <linux/uaccess.h> 68#include <linux/wait_api.h> 69#include <linux/wait_bit.h> 70#include <linux/workqueue_api.h> 71 72#include <trace/events/power.h> 73#include <trace/events/sched.h> 74 75#include "../workqueue_internal.h" 76 77#ifdef CONFIG_PARAVIRT 78# include <asm/paravirt.h> 79# include <asm/paravirt_api_clock.h> 80#endif 81 82#include <asm/barrier.h> 83 84#include "cpupri.h" 85#include "cpudeadline.h" 86 87#ifdef CONFIG_SCHED_DEBUG 88# define SCHED_WARN_ON(x) WARN_ONCE(x, #x) 89#else 90# define SCHED_WARN_ON(x) ({ (void)(x), 0; }) 91#endif 92 93struct rq; 94struct cpuidle_state; 95 96/* task_struct::on_rq states: */ 97#define TASK_ON_RQ_QUEUED 1 98#define TASK_ON_RQ_MIGRATING 2 99 100extern __read_mostly int scheduler_running; 101 102extern unsigned long calc_load_update; 103extern atomic_long_t calc_load_tasks; 104 105extern void calc_global_load_tick(struct rq *this_rq); 106extern long calc_load_fold_active(struct rq *this_rq, long adjust); 107 108extern void call_trace_sched_update_nr_running(struct rq *rq, int count); 109 110extern int sysctl_sched_rt_period; 111extern int sysctl_sched_rt_runtime; 112extern int sched_rr_timeslice; 113 114/* 115 * Helpers for converting nanosecond timing to jiffy resolution 116 */ 117#define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ)) 118 119/* 120 * Increase resolution of nice-level calculations for 64-bit architectures. 121 * The extra resolution improves shares distribution and load balancing of 122 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup 123 * hierarchies, especially on larger systems. This is not a user-visible change 124 * and does not change the user-interface for setting shares/weights. 125 * 126 * We increase resolution only if we have enough bits to allow this increased 127 * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit 128 * are pretty high and the returns do not justify the increased costs. 129 * 130 * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to 131 * increase coverage and consistency always enable it on 64-bit platforms. 132 */ 133#ifdef CONFIG_64BIT 134# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT) 135# define scale_load(w) ((w) << SCHED_FIXEDPOINT_SHIFT) 136# define scale_load_down(w) \ 137({ \ 138 unsigned long __w = (w); \ 139 if (__w) \ 140 __w = max(2UL, __w >> SCHED_FIXEDPOINT_SHIFT); \ 141 __w; \ 142}) 143#else 144# define NICE_0_LOAD_SHIFT (SCHED_FIXEDPOINT_SHIFT) 145# define scale_load(w) (w) 146# define scale_load_down(w) (w) 147#endif 148 149/* 150 * Task weight (visible to users) and its load (invisible to users) have 151 * independent resolution, but they should be well calibrated. We use 152 * scale_load() and scale_load_down(w) to convert between them. The 153 * following must be true: 154 * 155 * scale_load(sched_prio_to_weight[NICE_TO_PRIO(0)-MAX_RT_PRIO]) == NICE_0_LOAD 156 * 157 */ 158#define NICE_0_LOAD (1L << NICE_0_LOAD_SHIFT) 159 160/* 161 * Single value that decides SCHED_DEADLINE internal math precision. 162 * 10 -> just above 1us 163 * 9 -> just above 0.5us 164 */ 165#define DL_SCALE 10 166 167/* 168 * Single value that denotes runtime == period, ie unlimited time. 169 */ 170#define RUNTIME_INF ((u64)~0ULL) 171 172static inline int idle_policy(int policy) 173{ 174 return policy == SCHED_IDLE; 175} 176static inline int fair_policy(int policy) 177{ 178 return policy == SCHED_NORMAL || policy == SCHED_BATCH; 179} 180 181static inline int rt_policy(int policy) 182{ 183 return policy == SCHED_FIFO || policy == SCHED_RR; 184} 185 186static inline int dl_policy(int policy) 187{ 188 return policy == SCHED_DEADLINE; 189} 190static inline bool valid_policy(int policy) 191{ 192 return idle_policy(policy) || fair_policy(policy) || 193 rt_policy(policy) || dl_policy(policy); 194} 195 196static inline int task_has_idle_policy(struct task_struct *p) 197{ 198 return idle_policy(p->policy); 199} 200 201static inline int task_has_rt_policy(struct task_struct *p) 202{ 203 return rt_policy(p->policy); 204} 205 206static inline int task_has_dl_policy(struct task_struct *p) 207{ 208 return dl_policy(p->policy); 209} 210 211#define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT) 212 213static inline void update_avg(u64 *avg, u64 sample) 214{ 215 s64 diff = sample - *avg; 216 *avg += diff / 8; 217} 218 219/* 220 * Shifting a value by an exponent greater *or equal* to the size of said value 221 * is UB; cap at size-1. 222 */ 223#define shr_bound(val, shift) \ 224 (val >> min_t(typeof(shift), shift, BITS_PER_TYPE(typeof(val)) - 1)) 225 226/* 227 * !! For sched_setattr_nocheck() (kernel) only !! 228 * 229 * This is actually gross. :( 230 * 231 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE 232 * tasks, but still be able to sleep. We need this on platforms that cannot 233 * atomically change clock frequency. Remove once fast switching will be 234 * available on such platforms. 235 * 236 * SUGOV stands for SchedUtil GOVernor. 237 */ 238#define SCHED_FLAG_SUGOV 0x10000000 239 240#define SCHED_DL_FLAGS (SCHED_FLAG_RECLAIM | SCHED_FLAG_DL_OVERRUN | SCHED_FLAG_SUGOV) 241 242static inline bool dl_entity_is_special(const struct sched_dl_entity *dl_se) 243{ 244#ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL 245 return unlikely(dl_se->flags & SCHED_FLAG_SUGOV); 246#else 247 return false; 248#endif 249} 250 251/* 252 * Tells if entity @a should preempt entity @b. 253 */ 254static inline bool dl_entity_preempt(const struct sched_dl_entity *a, 255 const struct sched_dl_entity *b) 256{ 257 return dl_entity_is_special(a) || 258 dl_time_before(a->deadline, b->deadline); 259} 260 261/* 262 * This is the priority-queue data structure of the RT scheduling class: 263 */ 264struct rt_prio_array { 265 DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */ 266 struct list_head queue[MAX_RT_PRIO]; 267}; 268 269struct rt_bandwidth { 270 /* nests inside the rq lock: */ 271 raw_spinlock_t rt_runtime_lock; 272 ktime_t rt_period; 273 u64 rt_runtime; 274 struct hrtimer rt_period_timer; 275 unsigned int rt_period_active; 276}; 277 278static inline int dl_bandwidth_enabled(void) 279{ 280 return sysctl_sched_rt_runtime >= 0; 281} 282 283/* 284 * To keep the bandwidth of -deadline tasks under control 285 * we need some place where: 286 * - store the maximum -deadline bandwidth of each cpu; 287 * - cache the fraction of bandwidth that is currently allocated in 288 * each root domain; 289 * 290 * This is all done in the data structure below. It is similar to the 291 * one used for RT-throttling (rt_bandwidth), with the main difference 292 * that, since here we are only interested in admission control, we 293 * do not decrease any runtime while the group "executes", neither we 294 * need a timer to replenish it. 295 * 296 * With respect to SMP, bandwidth is given on a per root domain basis, 297 * meaning that: 298 * - bw (< 100%) is the deadline bandwidth of each CPU; 299 * - total_bw is the currently allocated bandwidth in each root domain; 300 */ 301struct dl_bw { 302 raw_spinlock_t lock; 303 u64 bw; 304 u64 total_bw; 305}; 306 307extern void init_dl_bw(struct dl_bw *dl_b); 308extern int sched_dl_global_validate(void); 309extern void sched_dl_do_global(void); 310extern int sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr); 311extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr); 312extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr); 313extern bool __checkparam_dl(const struct sched_attr *attr); 314extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr); 315extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 316extern int dl_bw_check_overflow(int cpu); 317 318/* 319 * SCHED_DEADLINE supports servers (nested scheduling) with the following 320 * interface: 321 * 322 * dl_se::rq -- runqueue we belong to. 323 * 324 * dl_se::server_has_tasks() -- used on bandwidth enforcement; we 'stop' the 325 * server when it runs out of tasks to run. 326 * 327 * dl_se::server_pick() -- nested pick_next_task(); we yield the period if this 328 * returns NULL. 329 * 330 * dl_server_update() -- called from update_curr_common(), propagates runtime 331 * to the server. 332 * 333 * dl_server_start() 334 * dl_server_stop() -- start/stop the server when it has (no) tasks. 335 * 336 * dl_server_init() -- initializes the server. 337 */ 338extern void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec); 339extern void dl_server_start(struct sched_dl_entity *dl_se); 340extern void dl_server_stop(struct sched_dl_entity *dl_se); 341extern void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq, 342 dl_server_has_tasks_f has_tasks, 343 dl_server_pick_f pick); 344 345#ifdef CONFIG_CGROUP_SCHED 346 347struct cfs_rq; 348struct rt_rq; 349 350extern struct list_head task_groups; 351 352struct cfs_bandwidth { 353#ifdef CONFIG_CFS_BANDWIDTH 354 raw_spinlock_t lock; 355 ktime_t period; 356 u64 quota; 357 u64 runtime; 358 u64 burst; 359 u64 runtime_snap; 360 s64 hierarchical_quota; 361 362 u8 idle; 363 u8 period_active; 364 u8 slack_started; 365 struct hrtimer period_timer; 366 struct hrtimer slack_timer; 367 struct list_head throttled_cfs_rq; 368 369 /* Statistics: */ 370 int nr_periods; 371 int nr_throttled; 372 int nr_burst; 373 u64 throttled_time; 374 u64 burst_time; 375#endif 376}; 377 378/* Task group related information */ 379struct task_group { 380 struct cgroup_subsys_state css; 381 382#ifdef CONFIG_FAIR_GROUP_SCHED 383 /* schedulable entities of this group on each CPU */ 384 struct sched_entity **se; 385 /* runqueue "owned" by this group on each CPU */ 386 struct cfs_rq **cfs_rq; 387 unsigned long shares; 388 389 /* A positive value indicates that this is a SCHED_IDLE group. */ 390 int idle; 391 392#ifdef CONFIG_SMP 393 /* 394 * load_avg can be heavily contended at clock tick time, so put 395 * it in its own cacheline separated from the fields above which 396 * will also be accessed at each tick. 397 */ 398 atomic_long_t load_avg ____cacheline_aligned; 399#endif 400#endif 401 402#ifdef CONFIG_RT_GROUP_SCHED 403 struct sched_rt_entity **rt_se; 404 struct rt_rq **rt_rq; 405 406 struct rt_bandwidth rt_bandwidth; 407#endif 408 409 struct rcu_head rcu; 410 struct list_head list; 411 412 struct task_group *parent; 413 struct list_head siblings; 414 struct list_head children; 415 416#ifdef CONFIG_SCHED_AUTOGROUP 417 struct autogroup *autogroup; 418#endif 419 420 struct cfs_bandwidth cfs_bandwidth; 421 422#ifdef CONFIG_UCLAMP_TASK_GROUP 423 /* The two decimal precision [%] value requested from user-space */ 424 unsigned int uclamp_pct[UCLAMP_CNT]; 425 /* Clamp values requested for a task group */ 426 struct uclamp_se uclamp_req[UCLAMP_CNT]; 427 /* Effective clamp values used for a task group */ 428 struct uclamp_se uclamp[UCLAMP_CNT]; 429#endif 430 431}; 432 433#ifdef CONFIG_FAIR_GROUP_SCHED 434#define ROOT_TASK_GROUP_LOAD NICE_0_LOAD 435 436/* 437 * A weight of 0 or 1 can cause arithmetics problems. 438 * A weight of a cfs_rq is the sum of weights of which entities 439 * are queued on this cfs_rq, so a weight of a entity should not be 440 * too large, so as the shares value of a task group. 441 * (The default weight is 1024 - so there's no practical 442 * limitation from this.) 443 */ 444#define MIN_SHARES (1UL << 1) 445#define MAX_SHARES (1UL << 18) 446#endif 447 448typedef int (*tg_visitor)(struct task_group *, void *); 449 450extern int walk_tg_tree_from(struct task_group *from, 451 tg_visitor down, tg_visitor up, void *data); 452 453/* 454 * Iterate the full tree, calling @down when first entering a node and @up when 455 * leaving it for the final time. 456 * 457 * Caller must hold rcu_lock or sufficient equivalent. 458 */ 459static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data) 460{ 461 return walk_tg_tree_from(&root_task_group, down, up, data); 462} 463 464extern int tg_nop(struct task_group *tg, void *data); 465 466#ifdef CONFIG_FAIR_GROUP_SCHED 467extern void free_fair_sched_group(struct task_group *tg); 468extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent); 469extern void online_fair_sched_group(struct task_group *tg); 470extern void unregister_fair_sched_group(struct task_group *tg); 471#else 472static inline void free_fair_sched_group(struct task_group *tg) { } 473static inline int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent) 474{ 475 return 1; 476} 477static inline void online_fair_sched_group(struct task_group *tg) { } 478static inline void unregister_fair_sched_group(struct task_group *tg) { } 479#endif 480 481extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq, 482 struct sched_entity *se, int cpu, 483 struct sched_entity *parent); 484extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b, struct cfs_bandwidth *parent); 485 486extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b); 487extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b); 488extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq); 489extern bool cfs_task_bw_constrained(struct task_struct *p); 490 491extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq, 492 struct sched_rt_entity *rt_se, int cpu, 493 struct sched_rt_entity *parent); 494extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us); 495extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us); 496extern long sched_group_rt_runtime(struct task_group *tg); 497extern long sched_group_rt_period(struct task_group *tg); 498extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk); 499 500extern struct task_group *sched_create_group(struct task_group *parent); 501extern void sched_online_group(struct task_group *tg, 502 struct task_group *parent); 503extern void sched_destroy_group(struct task_group *tg); 504extern void sched_release_group(struct task_group *tg); 505 506extern void sched_move_task(struct task_struct *tsk); 507 508#ifdef CONFIG_FAIR_GROUP_SCHED 509extern int sched_group_set_shares(struct task_group *tg, unsigned long shares); 510 511extern int sched_group_set_idle(struct task_group *tg, long idle); 512 513#ifdef CONFIG_SMP 514extern void set_task_rq_fair(struct sched_entity *se, 515 struct cfs_rq *prev, struct cfs_rq *next); 516#else /* !CONFIG_SMP */ 517static inline void set_task_rq_fair(struct sched_entity *se, 518 struct cfs_rq *prev, struct cfs_rq *next) { } 519#endif /* CONFIG_SMP */ 520#endif /* CONFIG_FAIR_GROUP_SCHED */ 521 522#else /* CONFIG_CGROUP_SCHED */ 523 524struct cfs_bandwidth { }; 525static inline bool cfs_task_bw_constrained(struct task_struct *p) { return false; } 526 527#endif /* CONFIG_CGROUP_SCHED */ 528 529extern void unregister_rt_sched_group(struct task_group *tg); 530extern void free_rt_sched_group(struct task_group *tg); 531extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent); 532 533/* 534 * u64_u32_load/u64_u32_store 535 * 536 * Use a copy of a u64 value to protect against data race. This is only 537 * applicable for 32-bits architectures. 538 */ 539#ifdef CONFIG_64BIT 540# define u64_u32_load_copy(var, copy) var 541# define u64_u32_store_copy(var, copy, val) (var = val) 542#else 543# define u64_u32_load_copy(var, copy) \ 544({ \ 545 u64 __val, __val_copy; \ 546 do { \ 547 __val_copy = copy; \ 548 /* \ 549 * paired with u64_u32_store_copy(), ordering access \ 550 * to var and copy. \ 551 */ \ 552 smp_rmb(); \ 553 __val = var; \ 554 } while (__val != __val_copy); \ 555 __val; \ 556}) 557# define u64_u32_store_copy(var, copy, val) \ 558do { \ 559 typeof(val) __val = (val); \ 560 var = __val; \ 561 /* \ 562 * paired with u64_u32_load_copy(), ordering access to var and \ 563 * copy. \ 564 */ \ 565 smp_wmb(); \ 566 copy = __val; \ 567} while (0) 568#endif 569# define u64_u32_load(var) u64_u32_load_copy(var, var##_copy) 570# define u64_u32_store(var, val) u64_u32_store_copy(var, var##_copy, val) 571 572/* CFS-related fields in a runqueue */ 573struct cfs_rq { 574 struct load_weight load; 575 unsigned int nr_running; 576 unsigned int h_nr_running; /* SCHED_{NORMAL,BATCH,IDLE} */ 577 unsigned int idle_nr_running; /* SCHED_IDLE */ 578 unsigned int idle_h_nr_running; /* SCHED_IDLE */ 579 580 s64 avg_vruntime; 581 u64 avg_load; 582 583 u64 exec_clock; 584 u64 min_vruntime; 585#ifdef CONFIG_SCHED_CORE 586 unsigned int forceidle_seq; 587 u64 min_vruntime_fi; 588#endif 589 590#ifndef CONFIG_64BIT 591 u64 min_vruntime_copy; 592#endif 593 594 struct rb_root_cached tasks_timeline; 595 596 /* 597 * 'curr' points to currently running entity on this cfs_rq. 598 * It is set to NULL otherwise (i.e when none are currently running). 599 */ 600 struct sched_entity *curr; 601 struct sched_entity *next; 602 603#ifdef CONFIG_SCHED_DEBUG 604 unsigned int nr_spread_over; 605#endif 606 607#ifdef CONFIG_SMP 608 /* 609 * CFS load tracking 610 */ 611 struct sched_avg avg; 612#ifndef CONFIG_64BIT 613 u64 last_update_time_copy; 614#endif 615 struct { 616 raw_spinlock_t lock ____cacheline_aligned; 617 int nr; 618 unsigned long load_avg; 619 unsigned long util_avg; 620 unsigned long runnable_avg; 621 } removed; 622 623#ifdef CONFIG_FAIR_GROUP_SCHED 624 u64 last_update_tg_load_avg; 625 unsigned long tg_load_avg_contrib; 626 long propagate; 627 long prop_runnable_sum; 628 629 /* 630 * h_load = weight * f(tg) 631 * 632 * Where f(tg) is the recursive weight fraction assigned to 633 * this group. 634 */ 635 unsigned long h_load; 636 u64 last_h_load_update; 637 struct sched_entity *h_load_next; 638#endif /* CONFIG_FAIR_GROUP_SCHED */ 639#endif /* CONFIG_SMP */ 640 641#ifdef CONFIG_FAIR_GROUP_SCHED 642 struct rq *rq; /* CPU runqueue to which this cfs_rq is attached */ 643 644 /* 645 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in 646 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities 647 * (like users, containers etc.) 648 * 649 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU. 650 * This list is used during load balance. 651 */ 652 int on_list; 653 struct list_head leaf_cfs_rq_list; 654 struct task_group *tg; /* group that "owns" this runqueue */ 655 656 /* Locally cached copy of our task_group's idle value */ 657 int idle; 658 659#ifdef CONFIG_CFS_BANDWIDTH 660 int runtime_enabled; 661 s64 runtime_remaining; 662 663 u64 throttled_pelt_idle; 664#ifndef CONFIG_64BIT 665 u64 throttled_pelt_idle_copy; 666#endif 667 u64 throttled_clock; 668 u64 throttled_clock_pelt; 669 u64 throttled_clock_pelt_time; 670 u64 throttled_clock_self; 671 u64 throttled_clock_self_time; 672 int throttled; 673 int throttle_count; 674 struct list_head throttled_list; 675 struct list_head throttled_csd_list; 676#endif /* CONFIG_CFS_BANDWIDTH */ 677#endif /* CONFIG_FAIR_GROUP_SCHED */ 678}; 679 680static inline int rt_bandwidth_enabled(void) 681{ 682 return sysctl_sched_rt_runtime >= 0; 683} 684 685/* RT IPI pull logic requires IRQ_WORK */ 686#if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP) 687# define HAVE_RT_PUSH_IPI 688#endif 689 690/* Real-Time classes' related field in a runqueue: */ 691struct rt_rq { 692 struct rt_prio_array active; 693 unsigned int rt_nr_running; 694 unsigned int rr_nr_running; 695#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED 696 struct { 697 int curr; /* highest queued rt task prio */ 698#ifdef CONFIG_SMP 699 int next; /* next highest */ 700#endif 701 } highest_prio; 702#endif 703#ifdef CONFIG_SMP 704 int overloaded; 705 struct plist_head pushable_tasks; 706 707#endif /* CONFIG_SMP */ 708 int rt_queued; 709 710 int rt_throttled; 711 u64 rt_time; 712 u64 rt_runtime; 713 /* Nests inside the rq lock: */ 714 raw_spinlock_t rt_runtime_lock; 715 716#ifdef CONFIG_RT_GROUP_SCHED 717 unsigned int rt_nr_boosted; 718 719 struct rq *rq; 720 struct task_group *tg; 721#endif 722}; 723 724static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq) 725{ 726 return rt_rq->rt_queued && rt_rq->rt_nr_running; 727} 728 729/* Deadline class' related fields in a runqueue */ 730struct dl_rq { 731 /* runqueue is an rbtree, ordered by deadline */ 732 struct rb_root_cached root; 733 734 unsigned int dl_nr_running; 735 736#ifdef CONFIG_SMP 737 /* 738 * Deadline values of the currently executing and the 739 * earliest ready task on this rq. Caching these facilitates 740 * the decision whether or not a ready but not running task 741 * should migrate somewhere else. 742 */ 743 struct { 744 u64 curr; 745 u64 next; 746 } earliest_dl; 747 748 int overloaded; 749 750 /* 751 * Tasks on this rq that can be pushed away. They are kept in 752 * an rb-tree, ordered by tasks' deadlines, with caching 753 * of the leftmost (earliest deadline) element. 754 */ 755 struct rb_root_cached pushable_dl_tasks_root; 756#else 757 struct dl_bw dl_bw; 758#endif 759 /* 760 * "Active utilization" for this runqueue: increased when a 761 * task wakes up (becomes TASK_RUNNING) and decreased when a 762 * task blocks 763 */ 764 u64 running_bw; 765 766 /* 767 * Utilization of the tasks "assigned" to this runqueue (including 768 * the tasks that are in runqueue and the tasks that executed on this 769 * CPU and blocked). Increased when a task moves to this runqueue, and 770 * decreased when the task moves away (migrates, changes scheduling 771 * policy, or terminates). 772 * This is needed to compute the "inactive utilization" for the 773 * runqueue (inactive utilization = this_bw - running_bw). 774 */ 775 u64 this_bw; 776 u64 extra_bw; 777 778 /* 779 * Maximum available bandwidth for reclaiming by SCHED_FLAG_RECLAIM 780 * tasks of this rq. Used in calculation of reclaimable bandwidth(GRUB). 781 */ 782 u64 max_bw; 783 784 /* 785 * Inverse of the fraction of CPU utilization that can be reclaimed 786 * by the GRUB algorithm. 787 */ 788 u64 bw_ratio; 789}; 790 791#ifdef CONFIG_FAIR_GROUP_SCHED 792/* An entity is a task if it doesn't "own" a runqueue */ 793#define entity_is_task(se) (!se->my_q) 794 795static inline void se_update_runnable(struct sched_entity *se) 796{ 797 if (!entity_is_task(se)) 798 se->runnable_weight = se->my_q->h_nr_running; 799} 800 801static inline long se_runnable(struct sched_entity *se) 802{ 803 if (entity_is_task(se)) 804 return !!se->on_rq; 805 else 806 return se->runnable_weight; 807} 808 809#else 810#define entity_is_task(se) 1 811 812static inline void se_update_runnable(struct sched_entity *se) {} 813 814static inline long se_runnable(struct sched_entity *se) 815{ 816 return !!se->on_rq; 817} 818#endif 819 820#ifdef CONFIG_SMP 821/* 822 * XXX we want to get rid of these helpers and use the full load resolution. 823 */ 824static inline long se_weight(struct sched_entity *se) 825{ 826 return scale_load_down(se->load.weight); 827} 828 829 830static inline bool sched_asym_prefer(int a, int b) 831{ 832 return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b); 833} 834 835struct perf_domain { 836 struct em_perf_domain *em_pd; 837 struct perf_domain *next; 838 struct rcu_head rcu; 839}; 840 841/* Scheduling group status flags */ 842#define SG_OVERLOAD 0x1 /* More than one runnable task on a CPU. */ 843#define SG_OVERUTILIZED 0x2 /* One or more CPUs are over-utilized. */ 844 845/* 846 * We add the notion of a root-domain which will be used to define per-domain 847 * variables. Each exclusive cpuset essentially defines an island domain by 848 * fully partitioning the member CPUs from any other cpuset. Whenever a new 849 * exclusive cpuset is created, we also create and attach a new root-domain 850 * object. 851 * 852 */ 853struct root_domain { 854 atomic_t refcount; 855 atomic_t rto_count; 856 struct rcu_head rcu; 857 cpumask_var_t span; 858 cpumask_var_t online; 859 860 /* 861 * Indicate pullable load on at least one CPU, e.g: 862 * - More than one runnable task 863 * - Running task is misfit 864 */ 865 int overload; 866 867 /* Indicate one or more cpus over-utilized (tipping point) */ 868 int overutilized; 869 870 /* 871 * The bit corresponding to a CPU gets set here if such CPU has more 872 * than one runnable -deadline task (as it is below for RT tasks). 873 */ 874 cpumask_var_t dlo_mask; 875 atomic_t dlo_count; 876 struct dl_bw dl_bw; 877 struct cpudl cpudl; 878 879 /* 880 * Indicate whether a root_domain's dl_bw has been checked or 881 * updated. It's monotonously increasing value. 882 * 883 * Also, some corner cases, like 'wrap around' is dangerous, but given 884 * that u64 is 'big enough'. So that shouldn't be a concern. 885 */ 886 u64 visit_gen; 887 888#ifdef HAVE_RT_PUSH_IPI 889 /* 890 * For IPI pull requests, loop across the rto_mask. 891 */ 892 struct irq_work rto_push_work; 893 raw_spinlock_t rto_lock; 894 /* These are only updated and read within rto_lock */ 895 int rto_loop; 896 int rto_cpu; 897 /* These atomics are updated outside of a lock */ 898 atomic_t rto_loop_next; 899 atomic_t rto_loop_start; 900#endif 901 /* 902 * The "RT overload" flag: it gets set if a CPU has more than 903 * one runnable RT task. 904 */ 905 cpumask_var_t rto_mask; 906 struct cpupri cpupri; 907 908 unsigned long max_cpu_capacity; 909 910 /* 911 * NULL-terminated list of performance domains intersecting with the 912 * CPUs of the rd. Protected by RCU. 913 */ 914 struct perf_domain __rcu *pd; 915}; 916 917extern void init_defrootdomain(void); 918extern int sched_init_domains(const struct cpumask *cpu_map); 919extern void rq_attach_root(struct rq *rq, struct root_domain *rd); 920extern void sched_get_rd(struct root_domain *rd); 921extern void sched_put_rd(struct root_domain *rd); 922 923#ifdef HAVE_RT_PUSH_IPI 924extern void rto_push_irq_work_func(struct irq_work *work); 925#endif 926#endif /* CONFIG_SMP */ 927 928#ifdef CONFIG_UCLAMP_TASK 929/* 930 * struct uclamp_bucket - Utilization clamp bucket 931 * @value: utilization clamp value for tasks on this clamp bucket 932 * @tasks: number of RUNNABLE tasks on this clamp bucket 933 * 934 * Keep track of how many tasks are RUNNABLE for a given utilization 935 * clamp value. 936 */ 937struct uclamp_bucket { 938 unsigned long value : bits_per(SCHED_CAPACITY_SCALE); 939 unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE); 940}; 941 942/* 943 * struct uclamp_rq - rq's utilization clamp 944 * @value: currently active clamp values for a rq 945 * @bucket: utilization clamp buckets affecting a rq 946 * 947 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values. 948 * A clamp value is affecting a rq when there is at least one task RUNNABLE 949 * (or actually running) with that value. 950 * 951 * There are up to UCLAMP_CNT possible different clamp values, currently there 952 * are only two: minimum utilization and maximum utilization. 953 * 954 * All utilization clamping values are MAX aggregated, since: 955 * - for util_min: we want to run the CPU at least at the max of the minimum 956 * utilization required by its currently RUNNABLE tasks. 957 * - for util_max: we want to allow the CPU to run up to the max of the 958 * maximum utilization allowed by its currently RUNNABLE tasks. 959 * 960 * Since on each system we expect only a limited number of different 961 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track 962 * the metrics required to compute all the per-rq utilization clamp values. 963 */ 964struct uclamp_rq { 965 unsigned int value; 966 struct uclamp_bucket bucket[UCLAMP_BUCKETS]; 967}; 968 969DECLARE_STATIC_KEY_FALSE(sched_uclamp_used); 970#endif /* CONFIG_UCLAMP_TASK */ 971 972struct rq; 973struct balance_callback { 974 struct balance_callback *next; 975 void (*func)(struct rq *rq); 976}; 977 978/* 979 * This is the main, per-CPU runqueue data structure. 980 * 981 * Locking rule: those places that want to lock multiple runqueues 982 * (such as the load balancing or the thread migration code), lock 983 * acquire operations must be ordered by ascending &runqueue. 984 */ 985struct rq { 986 /* runqueue lock: */ 987 raw_spinlock_t __lock; 988 989 unsigned int nr_running; 990#ifdef CONFIG_NUMA_BALANCING 991 unsigned int nr_numa_running; 992 unsigned int nr_preferred_running; 993 unsigned int numa_migrate_on; 994#endif 995#ifdef CONFIG_NO_HZ_COMMON 996#ifdef CONFIG_SMP 997 unsigned long last_blocked_load_update_tick; 998 unsigned int has_blocked_load; 999 call_single_data_t nohz_csd; 1000#endif /* CONFIG_SMP */ 1001 unsigned int nohz_tick_stopped; 1002 atomic_t nohz_flags; 1003#endif /* CONFIG_NO_HZ_COMMON */ 1004 1005#ifdef CONFIG_SMP 1006 unsigned int ttwu_pending; 1007#endif 1008 u64 nr_switches; 1009 1010#ifdef CONFIG_UCLAMP_TASK 1011 /* Utilization clamp values based on CPU's RUNNABLE tasks */ 1012 struct uclamp_rq uclamp[UCLAMP_CNT] ____cacheline_aligned; 1013 unsigned int uclamp_flags; 1014#define UCLAMP_FLAG_IDLE 0x01 1015#endif 1016 1017 struct cfs_rq cfs; 1018 struct rt_rq rt; 1019 struct dl_rq dl; 1020 1021#ifdef CONFIG_FAIR_GROUP_SCHED 1022 /* list of leaf cfs_rq on this CPU: */ 1023 struct list_head leaf_cfs_rq_list; 1024 struct list_head *tmp_alone_branch; 1025#endif /* CONFIG_FAIR_GROUP_SCHED */ 1026 1027 /* 1028 * This is part of a global counter where only the total sum 1029 * over all CPUs matters. A task can increase this counter on 1030 * one CPU and if it got migrated afterwards it may decrease 1031 * it on another CPU. Always updated under the runqueue lock: 1032 */ 1033 unsigned int nr_uninterruptible; 1034 1035 struct task_struct __rcu *curr; 1036 struct task_struct *idle; 1037 struct task_struct *stop; 1038 unsigned long next_balance; 1039 struct mm_struct *prev_mm; 1040 1041 unsigned int clock_update_flags; 1042 u64 clock; 1043 /* Ensure that all clocks are in the same cache line */ 1044 u64 clock_task ____cacheline_aligned; 1045 u64 clock_pelt; 1046 unsigned long lost_idle_time; 1047 u64 clock_pelt_idle; 1048 u64 clock_idle; 1049#ifndef CONFIG_64BIT 1050 u64 clock_pelt_idle_copy; 1051 u64 clock_idle_copy; 1052#endif 1053 1054 atomic_t nr_iowait; 1055 1056#ifdef CONFIG_SCHED_DEBUG 1057 u64 last_seen_need_resched_ns; 1058 int ticks_without_resched; 1059#endif 1060 1061#ifdef CONFIG_MEMBARRIER 1062 int membarrier_state; 1063#endif 1064 1065#ifdef CONFIG_SMP 1066 struct root_domain *rd; 1067 struct sched_domain __rcu *sd; 1068 1069 unsigned long cpu_capacity; 1070 1071 struct balance_callback *balance_callback; 1072 1073 unsigned char nohz_idle_balance; 1074 unsigned char idle_balance; 1075 1076 unsigned long misfit_task_load; 1077 1078 /* For active balancing */ 1079 int active_balance; 1080 int push_cpu; 1081 struct cpu_stop_work active_balance_work; 1082 1083 /* CPU of this runqueue: */ 1084 int cpu; 1085 int online; 1086 1087 struct list_head cfs_tasks; 1088 1089 struct sched_avg avg_rt; 1090 struct sched_avg avg_dl; 1091#ifdef CONFIG_HAVE_SCHED_AVG_IRQ 1092 struct sched_avg avg_irq; 1093#endif 1094#ifdef CONFIG_SCHED_THERMAL_PRESSURE 1095 struct sched_avg avg_thermal; 1096#endif 1097 u64 idle_stamp; 1098 u64 avg_idle; 1099 1100 /* This is used to determine avg_idle's max value */ 1101 u64 max_idle_balance_cost; 1102 1103#ifdef CONFIG_HOTPLUG_CPU 1104 struct rcuwait hotplug_wait; 1105#endif 1106#endif /* CONFIG_SMP */ 1107 1108#ifdef CONFIG_IRQ_TIME_ACCOUNTING 1109 u64 prev_irq_time; 1110#endif 1111#ifdef CONFIG_PARAVIRT 1112 u64 prev_steal_time; 1113#endif 1114#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING 1115 u64 prev_steal_time_rq; 1116#endif 1117 1118 /* calc_load related fields */ 1119 unsigned long calc_load_update; 1120 long calc_load_active; 1121 1122#ifdef CONFIG_SCHED_HRTICK 1123#ifdef CONFIG_SMP 1124 call_single_data_t hrtick_csd; 1125#endif 1126 struct hrtimer hrtick_timer; 1127 ktime_t hrtick_time; 1128#endif 1129 1130#ifdef CONFIG_SCHEDSTATS 1131 /* latency stats */ 1132 struct sched_info rq_sched_info; 1133 unsigned long long rq_cpu_time; 1134 /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */ 1135 1136 /* sys_sched_yield() stats */ 1137 unsigned int yld_count; 1138 1139 /* schedule() stats */ 1140 unsigned int sched_count; 1141 unsigned int sched_goidle; 1142 1143 /* try_to_wake_up() stats */ 1144 unsigned int ttwu_count; 1145 unsigned int ttwu_local; 1146#endif 1147 1148#ifdef CONFIG_CPU_IDLE 1149 /* Must be inspected within a rcu lock section */ 1150 struct cpuidle_state *idle_state; 1151#endif 1152 1153#ifdef CONFIG_SMP 1154 unsigned int nr_pinned; 1155#endif 1156 unsigned int push_busy; 1157 struct cpu_stop_work push_work; 1158 1159#ifdef CONFIG_SCHED_CORE 1160 /* per rq */ 1161 struct rq *core; 1162 struct task_struct *core_pick; 1163 unsigned int core_enabled; 1164 unsigned int core_sched_seq; 1165 struct rb_root core_tree; 1166 1167 /* shared state -- careful with sched_core_cpu_deactivate() */ 1168 unsigned int core_task_seq; 1169 unsigned int core_pick_seq; 1170 unsigned long core_cookie; 1171 unsigned int core_forceidle_count; 1172 unsigned int core_forceidle_seq; 1173 unsigned int core_forceidle_occupation; 1174 u64 core_forceidle_start; 1175#endif 1176 1177 /* Scratch cpumask to be temporarily used under rq_lock */ 1178 cpumask_var_t scratch_mask; 1179 1180#if defined(CONFIG_CFS_BANDWIDTH) && defined(CONFIG_SMP) 1181 call_single_data_t cfsb_csd; 1182 struct list_head cfsb_csd_list; 1183#endif 1184}; 1185 1186#ifdef CONFIG_FAIR_GROUP_SCHED 1187 1188/* CPU runqueue to which this cfs_rq is attached */ 1189static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1190{ 1191 return cfs_rq->rq; 1192} 1193 1194#else 1195 1196static inline struct rq *rq_of(struct cfs_rq *cfs_rq) 1197{ 1198 return container_of(cfs_rq, struct rq, cfs); 1199} 1200#endif 1201 1202static inline int cpu_of(struct rq *rq) 1203{ 1204#ifdef CONFIG_SMP 1205 return rq->cpu; 1206#else 1207 return 0; 1208#endif 1209} 1210 1211#define MDF_PUSH 0x01 1212 1213static inline bool is_migration_disabled(struct task_struct *p) 1214{ 1215#ifdef CONFIG_SMP 1216 return p->migration_disabled; 1217#else 1218 return false; 1219#endif 1220} 1221 1222DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); 1223 1224#define cpu_rq(cpu) (&per_cpu(runqueues, (cpu))) 1225#define this_rq() this_cpu_ptr(&runqueues) 1226#define task_rq(p) cpu_rq(task_cpu(p)) 1227#define cpu_curr(cpu) (cpu_rq(cpu)->curr) 1228#define raw_rq() raw_cpu_ptr(&runqueues) 1229 1230struct sched_group; 1231#ifdef CONFIG_SCHED_CORE 1232static inline struct cpumask *sched_group_span(struct sched_group *sg); 1233 1234DECLARE_STATIC_KEY_FALSE(__sched_core_enabled); 1235 1236static inline bool sched_core_enabled(struct rq *rq) 1237{ 1238 return static_branch_unlikely(&__sched_core_enabled) && rq->core_enabled; 1239} 1240 1241static inline bool sched_core_disabled(void) 1242{ 1243 return !static_branch_unlikely(&__sched_core_enabled); 1244} 1245 1246/* 1247 * Be careful with this function; not for general use. The return value isn't 1248 * stable unless you actually hold a relevant rq->__lock. 1249 */ 1250static inline raw_spinlock_t *rq_lockp(struct rq *rq) 1251{ 1252 if (sched_core_enabled(rq)) 1253 return &rq->core->__lock; 1254 1255 return &rq->__lock; 1256} 1257 1258static inline raw_spinlock_t *__rq_lockp(struct rq *rq) 1259{ 1260 if (rq->core_enabled) 1261 return &rq->core->__lock; 1262 1263 return &rq->__lock; 1264} 1265 1266bool cfs_prio_less(const struct task_struct *a, const struct task_struct *b, 1267 bool fi); 1268void task_vruntime_update(struct rq *rq, struct task_struct *p, bool in_fi); 1269 1270/* 1271 * Helpers to check if the CPU's core cookie matches with the task's cookie 1272 * when core scheduling is enabled. 1273 * A special case is that the task's cookie always matches with CPU's core 1274 * cookie if the CPU is in an idle core. 1275 */ 1276static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p) 1277{ 1278 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1279 if (!sched_core_enabled(rq)) 1280 return true; 1281 1282 return rq->core->core_cookie == p->core_cookie; 1283} 1284 1285static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) 1286{ 1287 bool idle_core = true; 1288 int cpu; 1289 1290 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1291 if (!sched_core_enabled(rq)) 1292 return true; 1293 1294 for_each_cpu(cpu, cpu_smt_mask(cpu_of(rq))) { 1295 if (!available_idle_cpu(cpu)) { 1296 idle_core = false; 1297 break; 1298 } 1299 } 1300 1301 /* 1302 * A CPU in an idle core is always the best choice for tasks with 1303 * cookies. 1304 */ 1305 return idle_core || rq->core->core_cookie == p->core_cookie; 1306} 1307 1308static inline bool sched_group_cookie_match(struct rq *rq, 1309 struct task_struct *p, 1310 struct sched_group *group) 1311{ 1312 int cpu; 1313 1314 /* Ignore cookie match if core scheduler is not enabled on the CPU. */ 1315 if (!sched_core_enabled(rq)) 1316 return true; 1317 1318 for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) { 1319 if (sched_core_cookie_match(cpu_rq(cpu), p)) 1320 return true; 1321 } 1322 return false; 1323} 1324 1325static inline bool sched_core_enqueued(struct task_struct *p) 1326{ 1327 return !RB_EMPTY_NODE(&p->core_node); 1328} 1329 1330extern void sched_core_enqueue(struct rq *rq, struct task_struct *p); 1331extern void sched_core_dequeue(struct rq *rq, struct task_struct *p, int flags); 1332 1333extern void sched_core_get(void); 1334extern void sched_core_put(void); 1335 1336#else /* !CONFIG_SCHED_CORE */ 1337 1338static inline bool sched_core_enabled(struct rq *rq) 1339{ 1340 return false; 1341} 1342 1343static inline bool sched_core_disabled(void) 1344{ 1345 return true; 1346} 1347 1348static inline raw_spinlock_t *rq_lockp(struct rq *rq) 1349{ 1350 return &rq->__lock; 1351} 1352 1353static inline raw_spinlock_t *__rq_lockp(struct rq *rq) 1354{ 1355 return &rq->__lock; 1356} 1357 1358static inline bool sched_cpu_cookie_match(struct rq *rq, struct task_struct *p) 1359{ 1360 return true; 1361} 1362 1363static inline bool sched_core_cookie_match(struct rq *rq, struct task_struct *p) 1364{ 1365 return true; 1366} 1367 1368static inline bool sched_group_cookie_match(struct rq *rq, 1369 struct task_struct *p, 1370 struct sched_group *group) 1371{ 1372 return true; 1373} 1374#endif /* CONFIG_SCHED_CORE */ 1375 1376static inline void lockdep_assert_rq_held(struct rq *rq) 1377{ 1378 lockdep_assert_held(__rq_lockp(rq)); 1379} 1380 1381extern void raw_spin_rq_lock_nested(struct rq *rq, int subclass); 1382extern bool raw_spin_rq_trylock(struct rq *rq); 1383extern void raw_spin_rq_unlock(struct rq *rq); 1384 1385static inline void raw_spin_rq_lock(struct rq *rq) 1386{ 1387 raw_spin_rq_lock_nested(rq, 0); 1388} 1389 1390static inline void raw_spin_rq_lock_irq(struct rq *rq) 1391{ 1392 local_irq_disable(); 1393 raw_spin_rq_lock(rq); 1394} 1395 1396static inline void raw_spin_rq_unlock_irq(struct rq *rq) 1397{ 1398 raw_spin_rq_unlock(rq); 1399 local_irq_enable(); 1400} 1401 1402static inline unsigned long _raw_spin_rq_lock_irqsave(struct rq *rq) 1403{ 1404 unsigned long flags; 1405 local_irq_save(flags); 1406 raw_spin_rq_lock(rq); 1407 return flags; 1408} 1409 1410static inline void raw_spin_rq_unlock_irqrestore(struct rq *rq, unsigned long flags) 1411{ 1412 raw_spin_rq_unlock(rq); 1413 local_irq_restore(flags); 1414} 1415 1416#define raw_spin_rq_lock_irqsave(rq, flags) \ 1417do { \ 1418 flags = _raw_spin_rq_lock_irqsave(rq); \ 1419} while (0) 1420 1421#ifdef CONFIG_SCHED_SMT 1422extern void __update_idle_core(struct rq *rq); 1423 1424static inline void update_idle_core(struct rq *rq) 1425{ 1426 if (static_branch_unlikely(&sched_smt_present)) 1427 __update_idle_core(rq); 1428} 1429 1430#else 1431static inline void update_idle_core(struct rq *rq) { } 1432#endif 1433 1434#ifdef CONFIG_FAIR_GROUP_SCHED 1435static inline struct task_struct *task_of(struct sched_entity *se) 1436{ 1437 SCHED_WARN_ON(!entity_is_task(se)); 1438 return container_of(se, struct task_struct, se); 1439} 1440 1441static inline struct cfs_rq *task_cfs_rq(struct task_struct *p) 1442{ 1443 return p->se.cfs_rq; 1444} 1445 1446/* runqueue on which this entity is (to be) queued */ 1447static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se) 1448{ 1449 return se->cfs_rq; 1450} 1451 1452/* runqueue "owned" by this group */ 1453static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) 1454{ 1455 return grp->my_q; 1456} 1457 1458#else 1459 1460#define task_of(_se) container_of(_se, struct task_struct, se) 1461 1462static inline struct cfs_rq *task_cfs_rq(const struct task_struct *p) 1463{ 1464 return &task_rq(p)->cfs; 1465} 1466 1467static inline struct cfs_rq *cfs_rq_of(const struct sched_entity *se) 1468{ 1469 const struct task_struct *p = task_of(se); 1470 struct rq *rq = task_rq(p); 1471 1472 return &rq->cfs; 1473} 1474 1475/* runqueue "owned" by this group */ 1476static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp) 1477{ 1478 return NULL; 1479} 1480#endif 1481 1482extern void update_rq_clock(struct rq *rq); 1483 1484/* 1485 * rq::clock_update_flags bits 1486 * 1487 * %RQCF_REQ_SKIP - will request skipping of clock update on the next 1488 * call to __schedule(). This is an optimisation to avoid 1489 * neighbouring rq clock updates. 1490 * 1491 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is 1492 * in effect and calls to update_rq_clock() are being ignored. 1493 * 1494 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been 1495 * made to update_rq_clock() since the last time rq::lock was pinned. 1496 * 1497 * If inside of __schedule(), clock_update_flags will have been 1498 * shifted left (a left shift is a cheap operation for the fast path 1499 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use, 1500 * 1501 * if (rq-clock_update_flags >= RQCF_UPDATED) 1502 * 1503 * to check if %RQCF_UPDATED is set. It'll never be shifted more than 1504 * one position though, because the next rq_unpin_lock() will shift it 1505 * back. 1506 */ 1507#define RQCF_REQ_SKIP 0x01 1508#define RQCF_ACT_SKIP 0x02 1509#define RQCF_UPDATED 0x04 1510 1511static inline void assert_clock_updated(struct rq *rq) 1512{ 1513 /* 1514 * The only reason for not seeing a clock update since the 1515 * last rq_pin_lock() is if we're currently skipping updates. 1516 */ 1517 SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP); 1518} 1519 1520static inline u64 rq_clock(struct rq *rq) 1521{ 1522 lockdep_assert_rq_held(rq); 1523 assert_clock_updated(rq); 1524 1525 return rq->clock; 1526} 1527 1528static inline u64 rq_clock_task(struct rq *rq) 1529{ 1530 lockdep_assert_rq_held(rq); 1531 assert_clock_updated(rq); 1532 1533 return rq->clock_task; 1534} 1535 1536/** 1537 * By default the decay is the default pelt decay period. 1538 * The decay shift can change the decay period in 1539 * multiples of 32. 1540 * Decay shift Decay period(ms) 1541 * 0 32 1542 * 1 64 1543 * 2 128 1544 * 3 256 1545 * 4 512 1546 */ 1547extern int sched_thermal_decay_shift; 1548 1549static inline u64 rq_clock_thermal(struct rq *rq) 1550{ 1551 return rq_clock_task(rq) >> sched_thermal_decay_shift; 1552} 1553 1554static inline void rq_clock_skip_update(struct rq *rq) 1555{ 1556 lockdep_assert_rq_held(rq); 1557 rq->clock_update_flags |= RQCF_REQ_SKIP; 1558} 1559 1560/* 1561 * See rt task throttling, which is the only time a skip 1562 * request is canceled. 1563 */ 1564static inline void rq_clock_cancel_skipupdate(struct rq *rq) 1565{ 1566 lockdep_assert_rq_held(rq); 1567 rq->clock_update_flags &= ~RQCF_REQ_SKIP; 1568} 1569 1570/* 1571 * During cpu offlining and rq wide unthrottling, we can trigger 1572 * an update_rq_clock() for several cfs and rt runqueues (Typically 1573 * when using list_for_each_entry_*) 1574 * rq_clock_start_loop_update() can be called after updating the clock 1575 * once and before iterating over the list to prevent multiple update. 1576 * After the iterative traversal, we need to call rq_clock_stop_loop_update() 1577 * to clear RQCF_ACT_SKIP of rq->clock_update_flags. 1578 */ 1579static inline void rq_clock_start_loop_update(struct rq *rq) 1580{ 1581 lockdep_assert_rq_held(rq); 1582 SCHED_WARN_ON(rq->clock_update_flags & RQCF_ACT_SKIP); 1583 rq->clock_update_flags |= RQCF_ACT_SKIP; 1584} 1585 1586static inline void rq_clock_stop_loop_update(struct rq *rq) 1587{ 1588 lockdep_assert_rq_held(rq); 1589 rq->clock_update_flags &= ~RQCF_ACT_SKIP; 1590} 1591 1592struct rq_flags { 1593 unsigned long flags; 1594 struct pin_cookie cookie; 1595#ifdef CONFIG_SCHED_DEBUG 1596 /* 1597 * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the 1598 * current pin context is stashed here in case it needs to be 1599 * restored in rq_repin_lock(). 1600 */ 1601 unsigned int clock_update_flags; 1602#endif 1603}; 1604 1605extern struct balance_callback balance_push_callback; 1606 1607/* 1608 * Lockdep annotation that avoids accidental unlocks; it's like a 1609 * sticky/continuous lockdep_assert_held(). 1610 * 1611 * This avoids code that has access to 'struct rq *rq' (basically everything in 1612 * the scheduler) from accidentally unlocking the rq if they do not also have a 1613 * copy of the (on-stack) 'struct rq_flags rf'. 1614 * 1615 * Also see Documentation/locking/lockdep-design.rst. 1616 */ 1617static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf) 1618{ 1619 rf->cookie = lockdep_pin_lock(__rq_lockp(rq)); 1620 1621#ifdef CONFIG_SCHED_DEBUG 1622 rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 1623 rf->clock_update_flags = 0; 1624#ifdef CONFIG_SMP 1625 SCHED_WARN_ON(rq->balance_callback && rq->balance_callback != &balance_push_callback); 1626#endif 1627#endif 1628} 1629 1630static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf) 1631{ 1632#ifdef CONFIG_SCHED_DEBUG 1633 if (rq->clock_update_flags > RQCF_ACT_SKIP) 1634 rf->clock_update_flags = RQCF_UPDATED; 1635#endif 1636 1637 lockdep_unpin_lock(__rq_lockp(rq), rf->cookie); 1638} 1639 1640static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf) 1641{ 1642 lockdep_repin_lock(__rq_lockp(rq), rf->cookie); 1643 1644#ifdef CONFIG_SCHED_DEBUG 1645 /* 1646 * Restore the value we stashed in @rf for this pin context. 1647 */ 1648 rq->clock_update_flags |= rf->clock_update_flags; 1649#endif 1650} 1651 1652struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1653 __acquires(rq->lock); 1654 1655struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf) 1656 __acquires(p->pi_lock) 1657 __acquires(rq->lock); 1658 1659static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf) 1660 __releases(rq->lock) 1661{ 1662 rq_unpin_lock(rq, rf); 1663 raw_spin_rq_unlock(rq); 1664} 1665 1666static inline void 1667task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) 1668 __releases(rq->lock) 1669 __releases(p->pi_lock) 1670{ 1671 rq_unpin_lock(rq, rf); 1672 raw_spin_rq_unlock(rq); 1673 raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); 1674} 1675 1676DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct, 1677 _T->rq = task_rq_lock(_T->lock, &_T->rf), 1678 task_rq_unlock(_T->rq, _T->lock, &_T->rf), 1679 struct rq *rq; struct rq_flags rf) 1680 1681static inline void 1682rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) 1683 __acquires(rq->lock) 1684{ 1685 raw_spin_rq_lock_irqsave(rq, rf->flags); 1686 rq_pin_lock(rq, rf); 1687} 1688 1689static inline void 1690rq_lock_irq(struct rq *rq, struct rq_flags *rf) 1691 __acquires(rq->lock) 1692{ 1693 raw_spin_rq_lock_irq(rq); 1694 rq_pin_lock(rq, rf); 1695} 1696 1697static inline void 1698rq_lock(struct rq *rq, struct rq_flags *rf) 1699 __acquires(rq->lock) 1700{ 1701 raw_spin_rq_lock(rq); 1702 rq_pin_lock(rq, rf); 1703} 1704 1705static inline void 1706rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf) 1707 __releases(rq->lock) 1708{ 1709 rq_unpin_lock(rq, rf); 1710 raw_spin_rq_unlock_irqrestore(rq, rf->flags); 1711} 1712 1713static inline void 1714rq_unlock_irq(struct rq *rq, struct rq_flags *rf) 1715 __releases(rq->lock) 1716{ 1717 rq_unpin_lock(rq, rf); 1718 raw_spin_rq_unlock_irq(rq); 1719} 1720 1721static inline void 1722rq_unlock(struct rq *rq, struct rq_flags *rf) 1723 __releases(rq->lock) 1724{ 1725 rq_unpin_lock(rq, rf); 1726 raw_spin_rq_unlock(rq); 1727} 1728 1729DEFINE_LOCK_GUARD_1(rq_lock, struct rq, 1730 rq_lock(_T->lock, &_T->rf), 1731 rq_unlock(_T->lock, &_T->rf), 1732 struct rq_flags rf) 1733 1734DEFINE_LOCK_GUARD_1(rq_lock_irq, struct rq, 1735 rq_lock_irq(_T->lock, &_T->rf), 1736 rq_unlock_irq(_T->lock, &_T->rf), 1737 struct rq_flags rf) 1738 1739DEFINE_LOCK_GUARD_1(rq_lock_irqsave, struct rq, 1740 rq_lock_irqsave(_T->lock, &_T->rf), 1741 rq_unlock_irqrestore(_T->lock, &_T->rf), 1742 struct rq_flags rf) 1743 1744static inline struct rq * 1745this_rq_lock_irq(struct rq_flags *rf) 1746 __acquires(rq->lock) 1747{ 1748 struct rq *rq; 1749 1750 local_irq_disable(); 1751 rq = this_rq(); 1752 rq_lock(rq, rf); 1753 return rq; 1754} 1755 1756#ifdef CONFIG_NUMA 1757enum numa_topology_type { 1758 NUMA_DIRECT, 1759 NUMA_GLUELESS_MESH, 1760 NUMA_BACKPLANE, 1761}; 1762extern enum numa_topology_type sched_numa_topology_type; 1763extern int sched_max_numa_distance; 1764extern bool find_numa_distance(int distance); 1765extern void sched_init_numa(int offline_node); 1766extern void sched_update_numa(int cpu, bool online); 1767extern void sched_domains_numa_masks_set(unsigned int cpu); 1768extern void sched_domains_numa_masks_clear(unsigned int cpu); 1769extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu); 1770#else 1771static inline void sched_init_numa(int offline_node) { } 1772static inline void sched_update_numa(int cpu, bool online) { } 1773static inline void sched_domains_numa_masks_set(unsigned int cpu) { } 1774static inline void sched_domains_numa_masks_clear(unsigned int cpu) { } 1775static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu) 1776{ 1777 return nr_cpu_ids; 1778} 1779#endif 1780 1781#ifdef CONFIG_NUMA_BALANCING 1782/* The regions in numa_faults array from task_struct */ 1783enum numa_faults_stats { 1784 NUMA_MEM = 0, 1785 NUMA_CPU, 1786 NUMA_MEMBUF, 1787 NUMA_CPUBUF 1788}; 1789extern void sched_setnuma(struct task_struct *p, int node); 1790extern int migrate_task_to(struct task_struct *p, int cpu); 1791extern int migrate_swap(struct task_struct *p, struct task_struct *t, 1792 int cpu, int scpu); 1793extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p); 1794#else 1795static inline void 1796init_numa_balancing(unsigned long clone_flags, struct task_struct *p) 1797{ 1798} 1799#endif /* CONFIG_NUMA_BALANCING */ 1800 1801#ifdef CONFIG_SMP 1802 1803static inline void 1804queue_balance_callback(struct rq *rq, 1805 struct balance_callback *head, 1806 void (*func)(struct rq *rq)) 1807{ 1808 lockdep_assert_rq_held(rq); 1809 1810 /* 1811 * Don't (re)queue an already queued item; nor queue anything when 1812 * balance_push() is active, see the comment with 1813 * balance_push_callback. 1814 */ 1815 if (unlikely(head->next || rq->balance_callback == &balance_push_callback)) 1816 return; 1817 1818 head->func = func; 1819 head->next = rq->balance_callback; 1820 rq->balance_callback = head; 1821} 1822 1823#define rcu_dereference_check_sched_domain(p) \ 1824 rcu_dereference_check((p), \ 1825 lockdep_is_held(&sched_domains_mutex)) 1826 1827/* 1828 * The domain tree (rq->sd) is protected by RCU's quiescent state transition. 1829 * See destroy_sched_domains: call_rcu for details. 1830 * 1831 * The domain tree of any CPU may only be accessed from within 1832 * preempt-disabled sections. 1833 */ 1834#define for_each_domain(cpu, __sd) \ 1835 for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \ 1836 __sd; __sd = __sd->parent) 1837 1838/* A mask of all the SD flags that have the SDF_SHARED_CHILD metaflag */ 1839#define SD_FLAG(name, mflags) (name * !!((mflags) & SDF_SHARED_CHILD)) | 1840static const unsigned int SD_SHARED_CHILD_MASK = 1841#include <linux/sched/sd_flags.h> 18420; 1843#undef SD_FLAG 1844 1845/** 1846 * highest_flag_domain - Return highest sched_domain containing flag. 1847 * @cpu: The CPU whose highest level of sched domain is to 1848 * be returned. 1849 * @flag: The flag to check for the highest sched_domain 1850 * for the given CPU. 1851 * 1852 * Returns the highest sched_domain of a CPU which contains @flag. If @flag has 1853 * the SDF_SHARED_CHILD metaflag, all the children domains also have @flag. 1854 */ 1855static inline struct sched_domain *highest_flag_domain(int cpu, int flag) 1856{ 1857 struct sched_domain *sd, *hsd = NULL; 1858 1859 for_each_domain(cpu, sd) { 1860 if (sd->flags & flag) { 1861 hsd = sd; 1862 continue; 1863 } 1864 1865 /* 1866 * Stop the search if @flag is known to be shared at lower 1867 * levels. It will not be found further up. 1868 */ 1869 if (flag & SD_SHARED_CHILD_MASK) 1870 break; 1871 } 1872 1873 return hsd; 1874} 1875 1876static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) 1877{ 1878 struct sched_domain *sd; 1879 1880 for_each_domain(cpu, sd) { 1881 if (sd->flags & flag) 1882 break; 1883 } 1884 1885 return sd; 1886} 1887 1888DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc); 1889DECLARE_PER_CPU(int, sd_llc_size); 1890DECLARE_PER_CPU(int, sd_llc_id); 1891DECLARE_PER_CPU(int, sd_share_id); 1892DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared); 1893DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa); 1894DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing); 1895DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity); 1896extern struct static_key_false sched_asym_cpucapacity; 1897extern struct static_key_false sched_cluster_active; 1898 1899static __always_inline bool sched_asym_cpucap_active(void) 1900{ 1901 return static_branch_unlikely(&sched_asym_cpucapacity); 1902} 1903 1904struct sched_group_capacity { 1905 atomic_t ref; 1906 /* 1907 * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity 1908 * for a single CPU. 1909 */ 1910 unsigned long capacity; 1911 unsigned long min_capacity; /* Min per-CPU capacity in group */ 1912 unsigned long max_capacity; /* Max per-CPU capacity in group */ 1913 unsigned long next_update; 1914 int imbalance; /* XXX unrelated to capacity but shared group state */ 1915 1916#ifdef CONFIG_SCHED_DEBUG 1917 int id; 1918#endif 1919 1920 unsigned long cpumask[]; /* Balance mask */ 1921}; 1922 1923struct sched_group { 1924 struct sched_group *next; /* Must be a circular list */ 1925 atomic_t ref; 1926 1927 unsigned int group_weight; 1928 unsigned int cores; 1929 struct sched_group_capacity *sgc; 1930 int asym_prefer_cpu; /* CPU of highest priority in group */ 1931 int flags; 1932 1933 /* 1934 * The CPUs this group covers. 1935 * 1936 * NOTE: this field is variable length. (Allocated dynamically 1937 * by attaching extra space to the end of the structure, 1938 * depending on how many CPUs the kernel has booted up with) 1939 */ 1940 unsigned long cpumask[]; 1941}; 1942 1943static inline struct cpumask *sched_group_span(struct sched_group *sg) 1944{ 1945 return to_cpumask(sg->cpumask); 1946} 1947 1948/* 1949 * See build_balance_mask(). 1950 */ 1951static inline struct cpumask *group_balance_mask(struct sched_group *sg) 1952{ 1953 return to_cpumask(sg->sgc->cpumask); 1954} 1955 1956extern int group_balance_cpu(struct sched_group *sg); 1957 1958#ifdef CONFIG_SCHED_DEBUG 1959void update_sched_domain_debugfs(void); 1960void dirty_sched_domain_sysctl(int cpu); 1961#else 1962static inline void update_sched_domain_debugfs(void) 1963{ 1964} 1965static inline void dirty_sched_domain_sysctl(int cpu) 1966{ 1967} 1968#endif 1969 1970extern int sched_update_scaling(void); 1971 1972static inline const struct cpumask *task_user_cpus(struct task_struct *p) 1973{ 1974 if (!p->user_cpus_ptr) 1975 return cpu_possible_mask; /* &init_task.cpus_mask */ 1976 return p->user_cpus_ptr; 1977} 1978#endif /* CONFIG_SMP */ 1979 1980#include "stats.h" 1981 1982#if defined(CONFIG_SCHED_CORE) && defined(CONFIG_SCHEDSTATS) 1983 1984extern void __sched_core_account_forceidle(struct rq *rq); 1985 1986static inline void sched_core_account_forceidle(struct rq *rq) 1987{ 1988 if (schedstat_enabled()) 1989 __sched_core_account_forceidle(rq); 1990} 1991 1992extern void __sched_core_tick(struct rq *rq); 1993 1994static inline void sched_core_tick(struct rq *rq) 1995{ 1996 if (sched_core_enabled(rq) && schedstat_enabled()) 1997 __sched_core_tick(rq); 1998} 1999 2000#else 2001 2002static inline void sched_core_account_forceidle(struct rq *rq) {} 2003 2004static inline void sched_core_tick(struct rq *rq) {} 2005 2006#endif /* CONFIG_SCHED_CORE && CONFIG_SCHEDSTATS */ 2007 2008#ifdef CONFIG_CGROUP_SCHED 2009 2010/* 2011 * Return the group to which this tasks belongs. 2012 * 2013 * We cannot use task_css() and friends because the cgroup subsystem 2014 * changes that value before the cgroup_subsys::attach() method is called, 2015 * therefore we cannot pin it and might observe the wrong value. 2016 * 2017 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup 2018 * core changes this before calling sched_move_task(). 2019 * 2020 * Instead we use a 'copy' which is updated from sched_move_task() while 2021 * holding both task_struct::pi_lock and rq::lock. 2022 */ 2023static inline struct task_group *task_group(struct task_struct *p) 2024{ 2025 return p->sched_task_group; 2026} 2027 2028/* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ 2029static inline void set_task_rq(struct task_struct *p, unsigned int cpu) 2030{ 2031#if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED) 2032 struct task_group *tg = task_group(p); 2033#endif 2034 2035#ifdef CONFIG_FAIR_GROUP_SCHED 2036 set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]); 2037 p->se.cfs_rq = tg->cfs_rq[cpu]; 2038 p->se.parent = tg->se[cpu]; 2039 p->se.depth = tg->se[cpu] ? tg->se[cpu]->depth + 1 : 0; 2040#endif 2041 2042#ifdef CONFIG_RT_GROUP_SCHED 2043 p->rt.rt_rq = tg->rt_rq[cpu]; 2044 p->rt.parent = tg->rt_se[cpu]; 2045#endif 2046} 2047 2048#else /* CONFIG_CGROUP_SCHED */ 2049 2050static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } 2051static inline struct task_group *task_group(struct task_struct *p) 2052{ 2053 return NULL; 2054} 2055 2056#endif /* CONFIG_CGROUP_SCHED */ 2057 2058static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) 2059{ 2060 set_task_rq(p, cpu); 2061#ifdef CONFIG_SMP 2062 /* 2063 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be 2064 * successfully executed on another CPU. We must ensure that updates of 2065 * per-task data have been completed by this moment. 2066 */ 2067 smp_wmb(); 2068 WRITE_ONCE(task_thread_info(p)->cpu, cpu); 2069 p->wake_cpu = cpu; 2070#endif 2071} 2072 2073/* 2074 * Tunables that become constants when CONFIG_SCHED_DEBUG is off: 2075 */ 2076#ifdef CONFIG_SCHED_DEBUG 2077# define const_debug __read_mostly 2078#else 2079# define const_debug const 2080#endif 2081 2082#define SCHED_FEAT(name, enabled) \ 2083 __SCHED_FEAT_##name , 2084 2085enum { 2086#include "features.h" 2087 __SCHED_FEAT_NR, 2088}; 2089 2090#undef SCHED_FEAT 2091 2092#ifdef CONFIG_SCHED_DEBUG 2093 2094/* 2095 * To support run-time toggling of sched features, all the translation units 2096 * (but core.c) reference the sysctl_sched_features defined in core.c. 2097 */ 2098extern const_debug unsigned int sysctl_sched_features; 2099 2100#ifdef CONFIG_JUMP_LABEL 2101#define SCHED_FEAT(name, enabled) \ 2102static __always_inline bool static_branch_##name(struct static_key *key) \ 2103{ \ 2104 return static_key_##enabled(key); \ 2105} 2106 2107#include "features.h" 2108#undef SCHED_FEAT 2109 2110extern struct static_key sched_feat_keys[__SCHED_FEAT_NR]; 2111#define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x])) 2112 2113#else /* !CONFIG_JUMP_LABEL */ 2114 2115#define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) 2116 2117#endif /* CONFIG_JUMP_LABEL */ 2118 2119#else /* !SCHED_DEBUG */ 2120 2121/* 2122 * Each translation unit has its own copy of sysctl_sched_features to allow 2123 * constants propagation at compile time and compiler optimization based on 2124 * features default. 2125 */ 2126#define SCHED_FEAT(name, enabled) \ 2127 (1UL << __SCHED_FEAT_##name) * enabled | 2128static const_debug __maybe_unused unsigned int sysctl_sched_features = 2129#include "features.h" 2130 0; 2131#undef SCHED_FEAT 2132 2133#define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) 2134 2135#endif /* SCHED_DEBUG */ 2136 2137extern struct static_key_false sched_numa_balancing; 2138extern struct static_key_false sched_schedstats; 2139 2140static inline u64 global_rt_period(void) 2141{ 2142 return (u64)sysctl_sched_rt_period * NSEC_PER_USEC; 2143} 2144 2145static inline u64 global_rt_runtime(void) 2146{ 2147 if (sysctl_sched_rt_runtime < 0) 2148 return RUNTIME_INF; 2149 2150 return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC; 2151} 2152 2153static inline int task_current(struct rq *rq, struct task_struct *p) 2154{ 2155 return rq->curr == p; 2156} 2157 2158static inline int task_on_cpu(struct rq *rq, struct task_struct *p) 2159{ 2160#ifdef CONFIG_SMP 2161 return p->on_cpu; 2162#else 2163 return task_current(rq, p); 2164#endif 2165} 2166 2167static inline int task_on_rq_queued(struct task_struct *p) 2168{ 2169 return p->on_rq == TASK_ON_RQ_QUEUED; 2170} 2171 2172static inline int task_on_rq_migrating(struct task_struct *p) 2173{ 2174 return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING; 2175} 2176 2177/* Wake flags. The first three directly map to some SD flag value */ 2178#define WF_EXEC 0x02 /* Wakeup after exec; maps to SD_BALANCE_EXEC */ 2179#define WF_FORK 0x04 /* Wakeup after fork; maps to SD_BALANCE_FORK */ 2180#define WF_TTWU 0x08 /* Wakeup; maps to SD_BALANCE_WAKE */ 2181 2182#define WF_SYNC 0x10 /* Waker goes to sleep after wakeup */ 2183#define WF_MIGRATED 0x20 /* Internal use, task got migrated */ 2184#define WF_CURRENT_CPU 0x40 /* Prefer to move the wakee to the current CPU. */ 2185 2186#ifdef CONFIG_SMP 2187static_assert(WF_EXEC == SD_BALANCE_EXEC); 2188static_assert(WF_FORK == SD_BALANCE_FORK); 2189static_assert(WF_TTWU == SD_BALANCE_WAKE); 2190#endif 2191 2192/* 2193 * To aid in avoiding the subversion of "niceness" due to uneven distribution 2194 * of tasks with abnormal "nice" values across CPUs the contribution that 2195 * each task makes to its run queue's load is weighted according to its 2196 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a 2197 * scaled version of the new time slice allocation that they receive on time 2198 * slice expiry etc. 2199 */ 2200 2201#define WEIGHT_IDLEPRIO 3 2202#define WMULT_IDLEPRIO 1431655765 2203 2204extern const int sched_prio_to_weight[40]; 2205extern const u32 sched_prio_to_wmult[40]; 2206 2207/* 2208 * {de,en}queue flags: 2209 * 2210 * DEQUEUE_SLEEP - task is no longer runnable 2211 * ENQUEUE_WAKEUP - task just became runnable 2212 * 2213 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks 2214 * are in a known state which allows modification. Such pairs 2215 * should preserve as much state as possible. 2216 * 2217 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location 2218 * in the runqueue. 2219 * 2220 * NOCLOCK - skip the update_rq_clock() (avoids double updates) 2221 * 2222 * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE) 2223 * 2224 * ENQUEUE_HEAD - place at front of runqueue (tail if not specified) 2225 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline) 2226 * ENQUEUE_MIGRATED - the task was migrated during wakeup 2227 * 2228 */ 2229 2230#define DEQUEUE_SLEEP 0x01 2231#define DEQUEUE_SAVE 0x02 /* Matches ENQUEUE_RESTORE */ 2232#define DEQUEUE_MOVE 0x04 /* Matches ENQUEUE_MOVE */ 2233#define DEQUEUE_NOCLOCK 0x08 /* Matches ENQUEUE_NOCLOCK */ 2234#define DEQUEUE_MIGRATING 0x100 /* Matches ENQUEUE_MIGRATING */ 2235 2236#define ENQUEUE_WAKEUP 0x01 2237#define ENQUEUE_RESTORE 0x02 2238#define ENQUEUE_MOVE 0x04 2239#define ENQUEUE_NOCLOCK 0x08 2240 2241#define ENQUEUE_HEAD 0x10 2242#define ENQUEUE_REPLENISH 0x20 2243#ifdef CONFIG_SMP 2244#define ENQUEUE_MIGRATED 0x40 2245#else 2246#define ENQUEUE_MIGRATED 0x00 2247#endif 2248#define ENQUEUE_INITIAL 0x80 2249#define ENQUEUE_MIGRATING 0x100 2250 2251#define RETRY_TASK ((void *)-1UL) 2252 2253struct affinity_context { 2254 const struct cpumask *new_mask; 2255 struct cpumask *user_mask; 2256 unsigned int flags; 2257}; 2258 2259extern s64 update_curr_common(struct rq *rq); 2260 2261struct sched_class { 2262 2263#ifdef CONFIG_UCLAMP_TASK 2264 int uclamp_enabled; 2265#endif 2266 2267 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags); 2268 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags); 2269 void (*yield_task) (struct rq *rq); 2270 bool (*yield_to_task)(struct rq *rq, struct task_struct *p); 2271 2272 void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags); 2273 2274 struct task_struct *(*pick_next_task)(struct rq *rq); 2275 2276 void (*put_prev_task)(struct rq *rq, struct task_struct *p); 2277 void (*set_next_task)(struct rq *rq, struct task_struct *p, bool first); 2278 2279#ifdef CONFIG_SMP 2280 int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf); 2281 int (*select_task_rq)(struct task_struct *p, int task_cpu, int flags); 2282 2283 struct task_struct * (*pick_task)(struct rq *rq); 2284 2285 void (*migrate_task_rq)(struct task_struct *p, int new_cpu); 2286 2287 void (*task_woken)(struct rq *this_rq, struct task_struct *task); 2288 2289 void (*set_cpus_allowed)(struct task_struct *p, struct affinity_context *ctx); 2290 2291 void (*rq_online)(struct rq *rq); 2292 void (*rq_offline)(struct rq *rq); 2293 2294 struct rq *(*find_lock_rq)(struct task_struct *p, struct rq *rq); 2295#endif 2296 2297 void (*task_tick)(struct rq *rq, struct task_struct *p, int queued); 2298 void (*task_fork)(struct task_struct *p); 2299 void (*task_dead)(struct task_struct *p); 2300 2301 /* 2302 * The switched_from() call is allowed to drop rq->lock, therefore we 2303 * cannot assume the switched_from/switched_to pair is serialized by 2304 * rq->lock. They are however serialized by p->pi_lock. 2305 */ 2306 void (*switched_from)(struct rq *this_rq, struct task_struct *task); 2307 void (*switched_to) (struct rq *this_rq, struct task_struct *task); 2308 void (*prio_changed) (struct rq *this_rq, struct task_struct *task, 2309 int oldprio); 2310 2311 unsigned int (*get_rr_interval)(struct rq *rq, 2312 struct task_struct *task); 2313 2314 void (*update_curr)(struct rq *rq); 2315 2316#ifdef CONFIG_FAIR_GROUP_SCHED 2317 void (*task_change_group)(struct task_struct *p); 2318#endif 2319 2320#ifdef CONFIG_SCHED_CORE 2321 int (*task_is_throttled)(struct task_struct *p, int cpu); 2322#endif 2323}; 2324 2325static inline void put_prev_task(struct rq *rq, struct task_struct *prev) 2326{ 2327 WARN_ON_ONCE(rq->curr != prev); 2328 prev->sched_class->put_prev_task(rq, prev); 2329} 2330 2331static inline void set_next_task(struct rq *rq, struct task_struct *next) 2332{ 2333 next->sched_class->set_next_task(rq, next, false); 2334} 2335 2336 2337/* 2338 * Helper to define a sched_class instance; each one is placed in a separate 2339 * section which is ordered by the linker script: 2340 * 2341 * include/asm-generic/vmlinux.lds.h 2342 * 2343 * *CAREFUL* they are laid out in *REVERSE* order!!! 2344 * 2345 * Also enforce alignment on the instance, not the type, to guarantee layout. 2346 */ 2347#define DEFINE_SCHED_CLASS(name) \ 2348const struct sched_class name##_sched_class \ 2349 __aligned(__alignof__(struct sched_class)) \ 2350 __section("__" #name "_sched_class") 2351 2352/* Defined in include/asm-generic/vmlinux.lds.h */ 2353extern struct sched_class __sched_class_highest[]; 2354extern struct sched_class __sched_class_lowest[]; 2355 2356#define for_class_range(class, _from, _to) \ 2357 for (class = (_from); class < (_to); class++) 2358 2359#define for_each_class(class) \ 2360 for_class_range(class, __sched_class_highest, __sched_class_lowest) 2361 2362#define sched_class_above(_a, _b) ((_a) < (_b)) 2363 2364extern const struct sched_class stop_sched_class; 2365extern const struct sched_class dl_sched_class; 2366extern const struct sched_class rt_sched_class; 2367extern const struct sched_class fair_sched_class; 2368extern const struct sched_class idle_sched_class; 2369 2370static inline bool sched_stop_runnable(struct rq *rq) 2371{ 2372 return rq->stop && task_on_rq_queued(rq->stop); 2373} 2374 2375static inline bool sched_dl_runnable(struct rq *rq) 2376{ 2377 return rq->dl.dl_nr_running > 0; 2378} 2379 2380static inline bool sched_rt_runnable(struct rq *rq) 2381{ 2382 return rq->rt.rt_queued > 0; 2383} 2384 2385static inline bool sched_fair_runnable(struct rq *rq) 2386{ 2387 return rq->cfs.nr_running > 0; 2388} 2389 2390extern struct task_struct *pick_next_task_fair(struct rq *rq, struct task_struct *prev, struct rq_flags *rf); 2391extern struct task_struct *pick_next_task_idle(struct rq *rq); 2392 2393#define SCA_CHECK 0x01 2394#define SCA_MIGRATE_DISABLE 0x02 2395#define SCA_MIGRATE_ENABLE 0x04 2396#define SCA_USER 0x08 2397 2398#ifdef CONFIG_SMP 2399 2400extern void update_group_capacity(struct sched_domain *sd, int cpu); 2401 2402extern void trigger_load_balance(struct rq *rq); 2403 2404extern void set_cpus_allowed_common(struct task_struct *p, struct affinity_context *ctx); 2405 2406static inline struct task_struct *get_push_task(struct rq *rq) 2407{ 2408 struct task_struct *p = rq->curr; 2409 2410 lockdep_assert_rq_held(rq); 2411 2412 if (rq->push_busy) 2413 return NULL; 2414 2415 if (p->nr_cpus_allowed == 1) 2416 return NULL; 2417 2418 if (p->migration_disabled) 2419 return NULL; 2420 2421 rq->push_busy = true; 2422 return get_task_struct(p); 2423} 2424 2425extern int push_cpu_stop(void *arg); 2426 2427#endif 2428 2429#ifdef CONFIG_CPU_IDLE 2430static inline void idle_set_state(struct rq *rq, 2431 struct cpuidle_state *idle_state) 2432{ 2433 rq->idle_state = idle_state; 2434} 2435 2436static inline struct cpuidle_state *idle_get_state(struct rq *rq) 2437{ 2438 SCHED_WARN_ON(!rcu_read_lock_held()); 2439 2440 return rq->idle_state; 2441} 2442#else 2443static inline void idle_set_state(struct rq *rq, 2444 struct cpuidle_state *idle_state) 2445{ 2446} 2447 2448static inline struct cpuidle_state *idle_get_state(struct rq *rq) 2449{ 2450 return NULL; 2451} 2452#endif 2453 2454extern void schedule_idle(void); 2455asmlinkage void schedule_user(void); 2456 2457extern void sysrq_sched_debug_show(void); 2458extern void sched_init_granularity(void); 2459extern void update_max_interval(void); 2460 2461extern void init_sched_dl_class(void); 2462extern void init_sched_rt_class(void); 2463extern void init_sched_fair_class(void); 2464 2465extern void reweight_task(struct task_struct *p, int prio); 2466 2467extern void resched_curr(struct rq *rq); 2468extern void resched_cpu(int cpu); 2469 2470extern struct rt_bandwidth def_rt_bandwidth; 2471extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime); 2472extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq); 2473 2474extern void init_dl_entity(struct sched_dl_entity *dl_se); 2475 2476#define BW_SHIFT 20 2477#define BW_UNIT (1 << BW_SHIFT) 2478#define RATIO_SHIFT 8 2479#define MAX_BW_BITS (64 - BW_SHIFT) 2480#define MAX_BW ((1ULL << MAX_BW_BITS) - 1) 2481unsigned long to_ratio(u64 period, u64 runtime); 2482 2483extern void init_entity_runnable_average(struct sched_entity *se); 2484extern void post_init_entity_util_avg(struct task_struct *p); 2485 2486#ifdef CONFIG_NO_HZ_FULL 2487extern bool sched_can_stop_tick(struct rq *rq); 2488extern int __init sched_tick_offload_init(void); 2489 2490/* 2491 * Tick may be needed by tasks in the runqueue depending on their policy and 2492 * requirements. If tick is needed, lets send the target an IPI to kick it out of 2493 * nohz mode if necessary. 2494 */ 2495static inline void sched_update_tick_dependency(struct rq *rq) 2496{ 2497 int cpu = cpu_of(rq); 2498 2499 if (!tick_nohz_full_cpu(cpu)) 2500 return; 2501 2502 if (sched_can_stop_tick(rq)) 2503 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED); 2504 else 2505 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED); 2506} 2507#else 2508static inline int sched_tick_offload_init(void) { return 0; } 2509static inline void sched_update_tick_dependency(struct rq *rq) { } 2510#endif 2511 2512static inline void add_nr_running(struct rq *rq, unsigned count) 2513{ 2514 unsigned prev_nr = rq->nr_running; 2515 2516 rq->nr_running = prev_nr + count; 2517 if (trace_sched_update_nr_running_tp_enabled()) { 2518 call_trace_sched_update_nr_running(rq, count); 2519 } 2520 2521#ifdef CONFIG_SMP 2522 if (prev_nr < 2 && rq->nr_running >= 2) { 2523 if (!READ_ONCE(rq->rd->overload)) 2524 WRITE_ONCE(rq->rd->overload, 1); 2525 } 2526#endif 2527 2528 sched_update_tick_dependency(rq); 2529} 2530 2531static inline void sub_nr_running(struct rq *rq, unsigned count) 2532{ 2533 rq->nr_running -= count; 2534 if (trace_sched_update_nr_running_tp_enabled()) { 2535 call_trace_sched_update_nr_running(rq, -count); 2536 } 2537 2538 /* Check if we still need preemption */ 2539 sched_update_tick_dependency(rq); 2540} 2541 2542extern void activate_task(struct rq *rq, struct task_struct *p, int flags); 2543extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags); 2544 2545extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags); 2546 2547#ifdef CONFIG_PREEMPT_RT 2548#define SCHED_NR_MIGRATE_BREAK 8 2549#else 2550#define SCHED_NR_MIGRATE_BREAK 32 2551#endif 2552 2553extern const_debug unsigned int sysctl_sched_nr_migrate; 2554extern const_debug unsigned int sysctl_sched_migration_cost; 2555 2556extern unsigned int sysctl_sched_base_slice; 2557 2558#ifdef CONFIG_SCHED_DEBUG 2559extern int sysctl_resched_latency_warn_ms; 2560extern int sysctl_resched_latency_warn_once; 2561 2562extern unsigned int sysctl_sched_tunable_scaling; 2563 2564extern unsigned int sysctl_numa_balancing_scan_delay; 2565extern unsigned int sysctl_numa_balancing_scan_period_min; 2566extern unsigned int sysctl_numa_balancing_scan_period_max; 2567extern unsigned int sysctl_numa_balancing_scan_size; 2568extern unsigned int sysctl_numa_balancing_hot_threshold; 2569#endif 2570 2571#ifdef CONFIG_SCHED_HRTICK 2572 2573/* 2574 * Use hrtick when: 2575 * - enabled by features 2576 * - hrtimer is actually high res 2577 */ 2578static inline int hrtick_enabled(struct rq *rq) 2579{ 2580 if (!cpu_active(cpu_of(rq))) 2581 return 0; 2582 return hrtimer_is_hres_active(&rq->hrtick_timer); 2583} 2584 2585static inline int hrtick_enabled_fair(struct rq *rq) 2586{ 2587 if (!sched_feat(HRTICK)) 2588 return 0; 2589 return hrtick_enabled(rq); 2590} 2591 2592static inline int hrtick_enabled_dl(struct rq *rq) 2593{ 2594 if (!sched_feat(HRTICK_DL)) 2595 return 0; 2596 return hrtick_enabled(rq); 2597} 2598 2599void hrtick_start(struct rq *rq, u64 delay); 2600 2601#else 2602 2603static inline int hrtick_enabled_fair(struct rq *rq) 2604{ 2605 return 0; 2606} 2607 2608static inline int hrtick_enabled_dl(struct rq *rq) 2609{ 2610 return 0; 2611} 2612 2613static inline int hrtick_enabled(struct rq *rq) 2614{ 2615 return 0; 2616} 2617 2618#endif /* CONFIG_SCHED_HRTICK */ 2619 2620#ifndef arch_scale_freq_tick 2621static __always_inline 2622void arch_scale_freq_tick(void) 2623{ 2624} 2625#endif 2626 2627#ifndef arch_scale_freq_capacity 2628/** 2629 * arch_scale_freq_capacity - get the frequency scale factor of a given CPU. 2630 * @cpu: the CPU in question. 2631 * 2632 * Return: the frequency scale factor normalized against SCHED_CAPACITY_SCALE, i.e. 2633 * 2634 * f_curr 2635 * ------ * SCHED_CAPACITY_SCALE 2636 * f_max 2637 */ 2638static __always_inline 2639unsigned long arch_scale_freq_capacity(int cpu) 2640{ 2641 return SCHED_CAPACITY_SCALE; 2642} 2643#endif 2644 2645#ifdef CONFIG_SCHED_DEBUG 2646/* 2647 * In double_lock_balance()/double_rq_lock(), we use raw_spin_rq_lock() to 2648 * acquire rq lock instead of rq_lock(). So at the end of these two functions 2649 * we need to call double_rq_clock_clear_update() to clear RQCF_UPDATED of 2650 * rq->clock_update_flags to avoid the WARN_DOUBLE_CLOCK warning. 2651 */ 2652static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) 2653{ 2654 rq1->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 2655 /* rq1 == rq2 for !CONFIG_SMP, so just clear RQCF_UPDATED once. */ 2656#ifdef CONFIG_SMP 2657 rq2->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP); 2658#endif 2659} 2660#else 2661static inline void double_rq_clock_clear_update(struct rq *rq1, struct rq *rq2) {} 2662#endif 2663 2664#define DEFINE_LOCK_GUARD_2(name, type, _lock, _unlock, ...) \ 2665__DEFINE_UNLOCK_GUARD(name, type, _unlock, type *lock2; __VA_ARGS__) \ 2666static inline class_##name##_t class_##name##_constructor(type *lock, type *lock2) \ 2667{ class_##name##_t _t = { .lock = lock, .lock2 = lock2 }, *_T = &_t; \ 2668 _lock; return _t; } 2669 2670#ifdef CONFIG_SMP 2671 2672static inline bool rq_order_less(struct rq *rq1, struct rq *rq2) 2673{ 2674#ifdef CONFIG_SCHED_CORE 2675 /* 2676 * In order to not have {0,2},{1,3} turn into into an AB-BA, 2677 * order by core-id first and cpu-id second. 2678 * 2679 * Notably: 2680 * 2681 * double_rq_lock(0,3); will take core-0, core-1 lock 2682 * double_rq_lock(1,2); will take core-1, core-0 lock 2683 * 2684 * when only cpu-id is considered. 2685 */ 2686 if (rq1->core->cpu < rq2->core->cpu) 2687 return true; 2688 if (rq1->core->cpu > rq2->core->cpu) 2689 return false; 2690 2691 /* 2692 * __sched_core_flip() relies on SMT having cpu-id lock order. 2693 */ 2694#endif 2695 return rq1->cpu < rq2->cpu; 2696} 2697 2698extern void double_rq_lock(struct rq *rq1, struct rq *rq2); 2699 2700#ifdef CONFIG_PREEMPTION 2701 2702/* 2703 * fair double_lock_balance: Safely acquires both rq->locks in a fair 2704 * way at the expense of forcing extra atomic operations in all 2705 * invocations. This assures that the double_lock is acquired using the 2706 * same underlying policy as the spinlock_t on this architecture, which 2707 * reduces latency compared to the unfair variant below. However, it 2708 * also adds more overhead and therefore may reduce throughput. 2709 */ 2710static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 2711 __releases(this_rq->lock) 2712 __acquires(busiest->lock) 2713 __acquires(this_rq->lock) 2714{ 2715 raw_spin_rq_unlock(this_rq); 2716 double_rq_lock(this_rq, busiest); 2717 2718 return 1; 2719} 2720 2721#else 2722/* 2723 * Unfair double_lock_balance: Optimizes throughput at the expense of 2724 * latency by eliminating extra atomic operations when the locks are 2725 * already in proper order on entry. This favors lower CPU-ids and will 2726 * grant the double lock to lower CPUs over higher ids under contention, 2727 * regardless of entry order into the function. 2728 */ 2729static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest) 2730 __releases(this_rq->lock) 2731 __acquires(busiest->lock) 2732 __acquires(this_rq->lock) 2733{ 2734 if (__rq_lockp(this_rq) == __rq_lockp(busiest) || 2735 likely(raw_spin_rq_trylock(busiest))) { 2736 double_rq_clock_clear_update(this_rq, busiest); 2737 return 0; 2738 } 2739 2740 if (rq_order_less(this_rq, busiest)) { 2741 raw_spin_rq_lock_nested(busiest, SINGLE_DEPTH_NESTING); 2742 double_rq_clock_clear_update(this_rq, busiest); 2743 return 0; 2744 } 2745 2746 raw_spin_rq_unlock(this_rq); 2747 double_rq_lock(this_rq, busiest); 2748 2749 return 1; 2750} 2751 2752#endif /* CONFIG_PREEMPTION */ 2753 2754/* 2755 * double_lock_balance - lock the busiest runqueue, this_rq is locked already. 2756 */ 2757static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest) 2758{ 2759 lockdep_assert_irqs_disabled(); 2760 2761 return _double_lock_balance(this_rq, busiest); 2762} 2763 2764static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest) 2765 __releases(busiest->lock) 2766{ 2767 if (__rq_lockp(this_rq) != __rq_lockp(busiest)) 2768 raw_spin_rq_unlock(busiest); 2769 lock_set_subclass(&__rq_lockp(this_rq)->dep_map, 0, _RET_IP_); 2770} 2771 2772static inline void double_lock(spinlock_t *l1, spinlock_t *l2) 2773{ 2774 if (l1 > l2) 2775 swap(l1, l2); 2776 2777 spin_lock(l1); 2778 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 2779} 2780 2781static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2) 2782{ 2783 if (l1 > l2) 2784 swap(l1, l2); 2785 2786 spin_lock_irq(l1); 2787 spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 2788} 2789 2790static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2) 2791{ 2792 if (l1 > l2) 2793 swap(l1, l2); 2794 2795 raw_spin_lock(l1); 2796 raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING); 2797} 2798 2799static inline void double_raw_unlock(raw_spinlock_t *l1, raw_spinlock_t *l2) 2800{ 2801 raw_spin_unlock(l1); 2802 raw_spin_unlock(l2); 2803} 2804 2805DEFINE_LOCK_GUARD_2(double_raw_spinlock, raw_spinlock_t, 2806 double_raw_lock(_T->lock, _T->lock2), 2807 double_raw_unlock(_T->lock, _T->lock2)) 2808 2809/* 2810 * double_rq_unlock - safely unlock two runqueues 2811 * 2812 * Note this does not restore interrupts like task_rq_unlock, 2813 * you need to do so manually after calling. 2814 */ 2815static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 2816 __releases(rq1->lock) 2817 __releases(rq2->lock) 2818{ 2819 if (__rq_lockp(rq1) != __rq_lockp(rq2)) 2820 raw_spin_rq_unlock(rq2); 2821 else 2822 __release(rq2->lock); 2823 raw_spin_rq_unlock(rq1); 2824} 2825 2826extern void set_rq_online (struct rq *rq); 2827extern void set_rq_offline(struct rq *rq); 2828extern bool sched_smp_initialized; 2829 2830#else /* CONFIG_SMP */ 2831 2832/* 2833 * double_rq_lock - safely lock two runqueues 2834 * 2835 * Note this does not disable interrupts like task_rq_lock, 2836 * you need to do so manually before calling. 2837 */ 2838static inline void double_rq_lock(struct rq *rq1, struct rq *rq2) 2839 __acquires(rq1->lock) 2840 __acquires(rq2->lock) 2841{ 2842 WARN_ON_ONCE(!irqs_disabled()); 2843 WARN_ON_ONCE(rq1 != rq2); 2844 raw_spin_rq_lock(rq1); 2845 __acquire(rq2->lock); /* Fake it out ;) */ 2846 double_rq_clock_clear_update(rq1, rq2); 2847} 2848 2849/* 2850 * double_rq_unlock - safely unlock two runqueues 2851 * 2852 * Note this does not restore interrupts like task_rq_unlock, 2853 * you need to do so manually after calling. 2854 */ 2855static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2) 2856 __releases(rq1->lock) 2857 __releases(rq2->lock) 2858{ 2859 WARN_ON_ONCE(rq1 != rq2); 2860 raw_spin_rq_unlock(rq1); 2861 __release(rq2->lock); 2862} 2863 2864#endif 2865 2866DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq, 2867 double_rq_lock(_T->lock, _T->lock2), 2868 double_rq_unlock(_T->lock, _T->lock2)) 2869 2870extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq); 2871extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq); 2872extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq); 2873 2874#ifdef CONFIG_SCHED_DEBUG 2875extern bool sched_debug_verbose; 2876 2877extern void print_cfs_stats(struct seq_file *m, int cpu); 2878extern void print_rt_stats(struct seq_file *m, int cpu); 2879extern void print_dl_stats(struct seq_file *m, int cpu); 2880extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq); 2881extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq); 2882extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq); 2883 2884extern void resched_latency_warn(int cpu, u64 latency); 2885#ifdef CONFIG_NUMA_BALANCING 2886extern void 2887show_numa_stats(struct task_struct *p, struct seq_file *m); 2888extern void 2889print_numa_stats(struct seq_file *m, int node, unsigned long tsf, 2890 unsigned long tpf, unsigned long gsf, unsigned long gpf); 2891#endif /* CONFIG_NUMA_BALANCING */ 2892#else 2893static inline void resched_latency_warn(int cpu, u64 latency) {} 2894#endif /* CONFIG_SCHED_DEBUG */ 2895 2896extern void init_cfs_rq(struct cfs_rq *cfs_rq); 2897extern void init_rt_rq(struct rt_rq *rt_rq); 2898extern void init_dl_rq(struct dl_rq *dl_rq); 2899 2900extern void cfs_bandwidth_usage_inc(void); 2901extern void cfs_bandwidth_usage_dec(void); 2902 2903#ifdef CONFIG_NO_HZ_COMMON 2904#define NOHZ_BALANCE_KICK_BIT 0 2905#define NOHZ_STATS_KICK_BIT 1 2906#define NOHZ_NEWILB_KICK_BIT 2 2907#define NOHZ_NEXT_KICK_BIT 3 2908 2909/* Run rebalance_domains() */ 2910#define NOHZ_BALANCE_KICK BIT(NOHZ_BALANCE_KICK_BIT) 2911/* Update blocked load */ 2912#define NOHZ_STATS_KICK BIT(NOHZ_STATS_KICK_BIT) 2913/* Update blocked load when entering idle */ 2914#define NOHZ_NEWILB_KICK BIT(NOHZ_NEWILB_KICK_BIT) 2915/* Update nohz.next_balance */ 2916#define NOHZ_NEXT_KICK BIT(NOHZ_NEXT_KICK_BIT) 2917 2918#define NOHZ_KICK_MASK (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK | NOHZ_NEXT_KICK) 2919 2920#define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags) 2921 2922extern void nohz_balance_exit_idle(struct rq *rq); 2923#else 2924static inline void nohz_balance_exit_idle(struct rq *rq) { } 2925#endif 2926 2927#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON) 2928extern void nohz_run_idle_balance(int cpu); 2929#else 2930static inline void nohz_run_idle_balance(int cpu) { } 2931#endif 2932 2933#ifdef CONFIG_IRQ_TIME_ACCOUNTING 2934struct irqtime { 2935 u64 total; 2936 u64 tick_delta; 2937 u64 irq_start_time; 2938 struct u64_stats_sync sync; 2939}; 2940 2941DECLARE_PER_CPU(struct irqtime, cpu_irqtime); 2942 2943/* 2944 * Returns the irqtime minus the softirq time computed by ksoftirqd. 2945 * Otherwise ksoftirqd's sum_exec_runtime is subtracted its own runtime 2946 * and never move forward. 2947 */ 2948static inline u64 irq_time_read(int cpu) 2949{ 2950 struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu); 2951 unsigned int seq; 2952 u64 total; 2953 2954 do { 2955 seq = __u64_stats_fetch_begin(&irqtime->sync); 2956 total = irqtime->total; 2957 } while (__u64_stats_fetch_retry(&irqtime->sync, seq)); 2958 2959 return total; 2960} 2961#endif /* CONFIG_IRQ_TIME_ACCOUNTING */ 2962 2963#ifdef CONFIG_CPU_FREQ 2964DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data); 2965 2966/** 2967 * cpufreq_update_util - Take a note about CPU utilization changes. 2968 * @rq: Runqueue to carry out the update for. 2969 * @flags: Update reason flags. 2970 * 2971 * This function is called by the scheduler on the CPU whose utilization is 2972 * being updated. 2973 * 2974 * It can only be called from RCU-sched read-side critical sections. 2975 * 2976 * The way cpufreq is currently arranged requires it to evaluate the CPU 2977 * performance state (frequency/voltage) on a regular basis to prevent it from 2978 * being stuck in a completely inadequate performance level for too long. 2979 * That is not guaranteed to happen if the updates are only triggered from CFS 2980 * and DL, though, because they may not be coming in if only RT tasks are 2981 * active all the time (or there are RT tasks only). 2982 * 2983 * As a workaround for that issue, this function is called periodically by the 2984 * RT sched class to trigger extra cpufreq updates to prevent it from stalling, 2985 * but that really is a band-aid. Going forward it should be replaced with 2986 * solutions targeted more specifically at RT tasks. 2987 */ 2988static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) 2989{ 2990 struct update_util_data *data; 2991 2992 data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data, 2993 cpu_of(rq))); 2994 if (data) 2995 data->func(data, rq_clock(rq), flags); 2996} 2997#else 2998static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {} 2999#endif /* CONFIG_CPU_FREQ */ 3000 3001#ifdef arch_scale_freq_capacity 3002# ifndef arch_scale_freq_invariant 3003# define arch_scale_freq_invariant() true 3004# endif 3005#else 3006# define arch_scale_freq_invariant() false 3007#endif 3008 3009#ifdef CONFIG_SMP 3010unsigned long effective_cpu_util(int cpu, unsigned long util_cfs, 3011 unsigned long *min, 3012 unsigned long *max); 3013 3014unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual, 3015 unsigned long min, 3016 unsigned long max); 3017 3018 3019/* 3020 * Verify the fitness of task @p to run on @cpu taking into account the 3021 * CPU original capacity and the runtime/deadline ratio of the task. 3022 * 3023 * The function will return true if the original capacity of @cpu is 3024 * greater than or equal to task's deadline density right shifted by 3025 * (BW_SHIFT - SCHED_CAPACITY_SHIFT) and false otherwise. 3026 */ 3027static inline bool dl_task_fits_capacity(struct task_struct *p, int cpu) 3028{ 3029 unsigned long cap = arch_scale_cpu_capacity(cpu); 3030 3031 return cap >= p->dl.dl_density >> (BW_SHIFT - SCHED_CAPACITY_SHIFT); 3032} 3033 3034static inline unsigned long cpu_bw_dl(struct rq *rq) 3035{ 3036 return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT; 3037} 3038 3039static inline unsigned long cpu_util_dl(struct rq *rq) 3040{ 3041 return READ_ONCE(rq->avg_dl.util_avg); 3042} 3043 3044 3045extern unsigned long cpu_util_cfs(int cpu); 3046extern unsigned long cpu_util_cfs_boost(int cpu); 3047 3048static inline unsigned long cpu_util_rt(struct rq *rq) 3049{ 3050 return READ_ONCE(rq->avg_rt.util_avg); 3051} 3052#endif 3053 3054#ifdef CONFIG_UCLAMP_TASK 3055unsigned long uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id); 3056 3057static inline unsigned long uclamp_rq_get(struct rq *rq, 3058 enum uclamp_id clamp_id) 3059{ 3060 return READ_ONCE(rq->uclamp[clamp_id].value); 3061} 3062 3063static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, 3064 unsigned int value) 3065{ 3066 WRITE_ONCE(rq->uclamp[clamp_id].value, value); 3067} 3068 3069static inline bool uclamp_rq_is_idle(struct rq *rq) 3070{ 3071 return rq->uclamp_flags & UCLAMP_FLAG_IDLE; 3072} 3073 3074/* Is the rq being capped/throttled by uclamp_max? */ 3075static inline bool uclamp_rq_is_capped(struct rq *rq) 3076{ 3077 unsigned long rq_util; 3078 unsigned long max_util; 3079 3080 if (!static_branch_likely(&sched_uclamp_used)) 3081 return false; 3082 3083 rq_util = cpu_util_cfs(cpu_of(rq)) + cpu_util_rt(rq); 3084 max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value); 3085 3086 return max_util != SCHED_CAPACITY_SCALE && rq_util >= max_util; 3087} 3088 3089/* 3090 * When uclamp is compiled in, the aggregation at rq level is 'turned off' 3091 * by default in the fast path and only gets turned on once userspace performs 3092 * an operation that requires it. 3093 * 3094 * Returns true if userspace opted-in to use uclamp and aggregation at rq level 3095 * hence is active. 3096 */ 3097static inline bool uclamp_is_used(void) 3098{ 3099 return static_branch_likely(&sched_uclamp_used); 3100} 3101#else /* CONFIG_UCLAMP_TASK */ 3102static inline unsigned long uclamp_eff_value(struct task_struct *p, 3103 enum uclamp_id clamp_id) 3104{ 3105 if (clamp_id == UCLAMP_MIN) 3106 return 0; 3107 3108 return SCHED_CAPACITY_SCALE; 3109} 3110 3111static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; } 3112 3113static inline bool uclamp_is_used(void) 3114{ 3115 return false; 3116} 3117 3118static inline unsigned long uclamp_rq_get(struct rq *rq, 3119 enum uclamp_id clamp_id) 3120{ 3121 if (clamp_id == UCLAMP_MIN) 3122 return 0; 3123 3124 return SCHED_CAPACITY_SCALE; 3125} 3126 3127static inline void uclamp_rq_set(struct rq *rq, enum uclamp_id clamp_id, 3128 unsigned int value) 3129{ 3130} 3131 3132static inline bool uclamp_rq_is_idle(struct rq *rq) 3133{ 3134 return false; 3135} 3136#endif /* CONFIG_UCLAMP_TASK */ 3137 3138#ifdef CONFIG_HAVE_SCHED_AVG_IRQ 3139static inline unsigned long cpu_util_irq(struct rq *rq) 3140{ 3141 return READ_ONCE(rq->avg_irq.util_avg); 3142} 3143 3144static inline 3145unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 3146{ 3147 util *= (max - irq); 3148 util /= max; 3149 3150 return util; 3151 3152} 3153#else 3154static inline unsigned long cpu_util_irq(struct rq *rq) 3155{ 3156 return 0; 3157} 3158 3159static inline 3160unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max) 3161{ 3162 return util; 3163} 3164#endif 3165 3166#if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL) 3167 3168#define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus))) 3169 3170DECLARE_STATIC_KEY_FALSE(sched_energy_present); 3171 3172static inline bool sched_energy_enabled(void) 3173{ 3174 return static_branch_unlikely(&sched_energy_present); 3175} 3176 3177extern struct cpufreq_governor schedutil_gov; 3178 3179#else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */ 3180 3181#define perf_domain_span(pd) NULL 3182static inline bool sched_energy_enabled(void) { return false; } 3183 3184#endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */ 3185 3186#ifdef CONFIG_MEMBARRIER 3187/* 3188 * The scheduler provides memory barriers required by membarrier between: 3189 * - prior user-space memory accesses and store to rq->membarrier_state, 3190 * - store to rq->membarrier_state and following user-space memory accesses. 3191 * In the same way it provides those guarantees around store to rq->curr. 3192 */ 3193static inline void membarrier_switch_mm(struct rq *rq, 3194 struct mm_struct *prev_mm, 3195 struct mm_struct *next_mm) 3196{ 3197 int membarrier_state; 3198 3199 if (prev_mm == next_mm) 3200 return; 3201 3202 membarrier_state = atomic_read(&next_mm->membarrier_state); 3203 if (READ_ONCE(rq->membarrier_state) == membarrier_state) 3204 return; 3205 3206 WRITE_ONCE(rq->membarrier_state, membarrier_state); 3207} 3208#else 3209static inline void membarrier_switch_mm(struct rq *rq, 3210 struct mm_struct *prev_mm, 3211 struct mm_struct *next_mm) 3212{ 3213} 3214#endif 3215 3216#ifdef CONFIG_SMP 3217static inline bool is_per_cpu_kthread(struct task_struct *p) 3218{ 3219 if (!(p->flags & PF_KTHREAD)) 3220 return false; 3221 3222 if (p->nr_cpus_allowed != 1) 3223 return false; 3224 3225 return true; 3226} 3227#endif 3228 3229extern void swake_up_all_locked(struct swait_queue_head *q); 3230extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait); 3231 3232extern int try_to_wake_up(struct task_struct *tsk, unsigned int state, int wake_flags); 3233 3234#ifdef CONFIG_PREEMPT_DYNAMIC 3235extern int preempt_dynamic_mode; 3236extern int sched_dynamic_mode(const char *str); 3237extern void sched_dynamic_update(int mode); 3238#endif 3239 3240#ifdef CONFIG_SCHED_MM_CID 3241 3242#define SCHED_MM_CID_PERIOD_NS (100ULL * 1000000) /* 100ms */ 3243#define MM_CID_SCAN_DELAY 100 /* 100ms */ 3244 3245extern raw_spinlock_t cid_lock; 3246extern int use_cid_lock; 3247 3248extern void sched_mm_cid_migrate_from(struct task_struct *t); 3249extern void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t); 3250extern void task_tick_mm_cid(struct rq *rq, struct task_struct *curr); 3251extern void init_sched_mm_cid(struct task_struct *t); 3252 3253static inline void __mm_cid_put(struct mm_struct *mm, int cid) 3254{ 3255 if (cid < 0) 3256 return; 3257 cpumask_clear_cpu(cid, mm_cidmask(mm)); 3258} 3259 3260/* 3261 * The per-mm/cpu cid can have the MM_CID_LAZY_PUT flag set or transition to 3262 * the MM_CID_UNSET state without holding the rq lock, but the rq lock needs to 3263 * be held to transition to other states. 3264 * 3265 * State transitions synchronized with cmpxchg or try_cmpxchg need to be 3266 * consistent across cpus, which prevents use of this_cpu_cmpxchg. 3267 */ 3268static inline void mm_cid_put_lazy(struct task_struct *t) 3269{ 3270 struct mm_struct *mm = t->mm; 3271 struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid; 3272 int cid; 3273 3274 lockdep_assert_irqs_disabled(); 3275 cid = __this_cpu_read(pcpu_cid->cid); 3276 if (!mm_cid_is_lazy_put(cid) || 3277 !try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET)) 3278 return; 3279 __mm_cid_put(mm, mm_cid_clear_lazy_put(cid)); 3280} 3281 3282static inline int mm_cid_pcpu_unset(struct mm_struct *mm) 3283{ 3284 struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid; 3285 int cid, res; 3286 3287 lockdep_assert_irqs_disabled(); 3288 cid = __this_cpu_read(pcpu_cid->cid); 3289 for (;;) { 3290 if (mm_cid_is_unset(cid)) 3291 return MM_CID_UNSET; 3292 /* 3293 * Attempt transition from valid or lazy-put to unset. 3294 */ 3295 res = cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, cid, MM_CID_UNSET); 3296 if (res == cid) 3297 break; 3298 cid = res; 3299 } 3300 return cid; 3301} 3302 3303static inline void mm_cid_put(struct mm_struct *mm) 3304{ 3305 int cid; 3306 3307 lockdep_assert_irqs_disabled(); 3308 cid = mm_cid_pcpu_unset(mm); 3309 if (cid == MM_CID_UNSET) 3310 return; 3311 __mm_cid_put(mm, mm_cid_clear_lazy_put(cid)); 3312} 3313 3314static inline int __mm_cid_try_get(struct mm_struct *mm) 3315{ 3316 struct cpumask *cpumask; 3317 int cid; 3318 3319 cpumask = mm_cidmask(mm); 3320 /* 3321 * Retry finding first zero bit if the mask is temporarily 3322 * filled. This only happens during concurrent remote-clear 3323 * which owns a cid without holding a rq lock. 3324 */ 3325 for (;;) { 3326 cid = cpumask_first_zero(cpumask); 3327 if (cid < nr_cpu_ids) 3328 break; 3329 cpu_relax(); 3330 } 3331 if (cpumask_test_and_set_cpu(cid, cpumask)) 3332 return -1; 3333 return cid; 3334} 3335 3336/* 3337 * Save a snapshot of the current runqueue time of this cpu 3338 * with the per-cpu cid value, allowing to estimate how recently it was used. 3339 */ 3340static inline void mm_cid_snapshot_time(struct rq *rq, struct mm_struct *mm) 3341{ 3342 struct mm_cid *pcpu_cid = per_cpu_ptr(mm->pcpu_cid, cpu_of(rq)); 3343 3344 lockdep_assert_rq_held(rq); 3345 WRITE_ONCE(pcpu_cid->time, rq->clock); 3346} 3347 3348static inline int __mm_cid_get(struct rq *rq, struct mm_struct *mm) 3349{ 3350 int cid; 3351 3352 /* 3353 * All allocations (even those using the cid_lock) are lock-free. If 3354 * use_cid_lock is set, hold the cid_lock to perform cid allocation to 3355 * guarantee forward progress. 3356 */ 3357 if (!READ_ONCE(use_cid_lock)) { 3358 cid = __mm_cid_try_get(mm); 3359 if (cid >= 0) 3360 goto end; 3361 raw_spin_lock(&cid_lock); 3362 } else { 3363 raw_spin_lock(&cid_lock); 3364 cid = __mm_cid_try_get(mm); 3365 if (cid >= 0) 3366 goto unlock; 3367 } 3368 3369 /* 3370 * cid concurrently allocated. Retry while forcing following 3371 * allocations to use the cid_lock to ensure forward progress. 3372 */ 3373 WRITE_ONCE(use_cid_lock, 1); 3374 /* 3375 * Set use_cid_lock before allocation. Only care about program order 3376 * because this is only required for forward progress. 3377 */ 3378 barrier(); 3379 /* 3380 * Retry until it succeeds. It is guaranteed to eventually succeed once 3381 * all newcoming allocations observe the use_cid_lock flag set. 3382 */ 3383 do { 3384 cid = __mm_cid_try_get(mm); 3385 cpu_relax(); 3386 } while (cid < 0); 3387 /* 3388 * Allocate before clearing use_cid_lock. Only care about 3389 * program order because this is for forward progress. 3390 */ 3391 barrier(); 3392 WRITE_ONCE(use_cid_lock, 0); 3393unlock: 3394 raw_spin_unlock(&cid_lock); 3395end: 3396 mm_cid_snapshot_time(rq, mm); 3397 return cid; 3398} 3399 3400static inline int mm_cid_get(struct rq *rq, struct mm_struct *mm) 3401{ 3402 struct mm_cid __percpu *pcpu_cid = mm->pcpu_cid; 3403 struct cpumask *cpumask; 3404 int cid; 3405 3406 lockdep_assert_rq_held(rq); 3407 cpumask = mm_cidmask(mm); 3408 cid = __this_cpu_read(pcpu_cid->cid); 3409 if (mm_cid_is_valid(cid)) { 3410 mm_cid_snapshot_time(rq, mm); 3411 return cid; 3412 } 3413 if (mm_cid_is_lazy_put(cid)) { 3414 if (try_cmpxchg(&this_cpu_ptr(pcpu_cid)->cid, &cid, MM_CID_UNSET)) 3415 __mm_cid_put(mm, mm_cid_clear_lazy_put(cid)); 3416 } 3417 cid = __mm_cid_get(rq, mm); 3418 __this_cpu_write(pcpu_cid->cid, cid); 3419 return cid; 3420} 3421 3422static inline void switch_mm_cid(struct rq *rq, 3423 struct task_struct *prev, 3424 struct task_struct *next) 3425{ 3426 /* 3427 * Provide a memory barrier between rq->curr store and load of 3428 * {prev,next}->mm->pcpu_cid[cpu] on rq->curr->mm transition. 3429 * 3430 * Should be adapted if context_switch() is modified. 3431 */ 3432 if (!next->mm) { // to kernel 3433 /* 3434 * user -> kernel transition does not guarantee a barrier, but 3435 * we can use the fact that it performs an atomic operation in 3436 * mmgrab(). 3437 */ 3438 if (prev->mm) // from user 3439 smp_mb__after_mmgrab(); 3440 /* 3441 * kernel -> kernel transition does not change rq->curr->mm 3442 * state. It stays NULL. 3443 */ 3444 } else { // to user 3445 /* 3446 * kernel -> user transition does not provide a barrier 3447 * between rq->curr store and load of {prev,next}->mm->pcpu_cid[cpu]. 3448 * Provide it here. 3449 */ 3450 if (!prev->mm) { // from kernel 3451 smp_mb(); 3452 } else { // from user 3453 /* 3454 * user->user transition relies on an implicit 3455 * memory barrier in switch_mm() when 3456 * current->mm changes. If the architecture 3457 * switch_mm() does not have an implicit memory 3458 * barrier, it is emitted here. If current->mm 3459 * is unchanged, no barrier is needed. 3460 */ 3461 smp_mb__after_switch_mm(); 3462 } 3463 } 3464 if (prev->mm_cid_active) { 3465 mm_cid_snapshot_time(rq, prev->mm); 3466 mm_cid_put_lazy(prev); 3467 prev->mm_cid = -1; 3468 } 3469 if (next->mm_cid_active) 3470 next->last_mm_cid = next->mm_cid = mm_cid_get(rq, next->mm); 3471} 3472 3473#else 3474static inline void switch_mm_cid(struct rq *rq, struct task_struct *prev, struct task_struct *next) { } 3475static inline void sched_mm_cid_migrate_from(struct task_struct *t) { } 3476static inline void sched_mm_cid_migrate_to(struct rq *dst_rq, struct task_struct *t) { } 3477static inline void task_tick_mm_cid(struct rq *rq, struct task_struct *curr) { } 3478static inline void init_sched_mm_cid(struct task_struct *t) { } 3479#endif 3480 3481extern u64 avg_vruntime(struct cfs_rq *cfs_rq); 3482extern int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se); 3483 3484#endif /* _KERNEL_SCHED_SCHED_H */ 3485