linux/kernel/sched/sched.h
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   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * Scheduler internal types and methods:
   4 */
   5#include <linux/sched.h>
   6
   7#include <linux/sched/autogroup.h>
   8#include <linux/sched/clock.h>
   9#include <linux/sched/coredump.h>
  10#include <linux/sched/cpufreq.h>
  11#include <linux/sched/cputime.h>
  12#include <linux/sched/deadline.h>
  13#include <linux/sched/debug.h>
  14#include <linux/sched/hotplug.h>
  15#include <linux/sched/idle.h>
  16#include <linux/sched/init.h>
  17#include <linux/sched/isolation.h>
  18#include <linux/sched/jobctl.h>
  19#include <linux/sched/loadavg.h>
  20#include <linux/sched/mm.h>
  21#include <linux/sched/nohz.h>
  22#include <linux/sched/numa_balancing.h>
  23#include <linux/sched/prio.h>
  24#include <linux/sched/rt.h>
  25#include <linux/sched/signal.h>
  26#include <linux/sched/smt.h>
  27#include <linux/sched/stat.h>
  28#include <linux/sched/sysctl.h>
  29#include <linux/sched/task.h>
  30#include <linux/sched/task_stack.h>
  31#include <linux/sched/topology.h>
  32#include <linux/sched/user.h>
  33#include <linux/sched/wake_q.h>
  34#include <linux/sched/xacct.h>
  35
  36#include <uapi/linux/sched/types.h>
  37
  38#include <linux/binfmts.h>
  39#include <linux/blkdev.h>
  40#include <linux/compat.h>
  41#include <linux/context_tracking.h>
  42#include <linux/cpufreq.h>
  43#include <linux/cpuidle.h>
  44#include <linux/cpuset.h>
  45#include <linux/ctype.h>
  46#include <linux/debugfs.h>
  47#include <linux/delayacct.h>
  48#include <linux/energy_model.h>
  49#include <linux/init_task.h>
  50#include <linux/kprobes.h>
  51#include <linux/kthread.h>
  52#include <linux/membarrier.h>
  53#include <linux/migrate.h>
  54#include <linux/mmu_context.h>
  55#include <linux/nmi.h>
  56#include <linux/proc_fs.h>
  57#include <linux/prefetch.h>
  58#include <linux/profile.h>
  59#include <linux/psi.h>
  60#include <linux/rcupdate_wait.h>
  61#include <linux/security.h>
  62#include <linux/stop_machine.h>
  63#include <linux/suspend.h>
  64#include <linux/swait.h>
  65#include <linux/syscalls.h>
  66#include <linux/task_work.h>
  67#include <linux/tsacct_kern.h>
  68
  69#include <asm/tlb.h>
  70
  71#ifdef CONFIG_PARAVIRT
  72# include <asm/paravirt.h>
  73#endif
  74
  75#include "cpupri.h"
  76#include "cpudeadline.h"
  77
  78#ifdef CONFIG_SCHED_DEBUG
  79# define SCHED_WARN_ON(x)       WARN_ONCE(x, #x)
  80#else
  81# define SCHED_WARN_ON(x)       ({ (void)(x), 0; })
  82#endif
  83
  84struct rq;
  85struct cpuidle_state;
  86
  87/* task_struct::on_rq states: */
  88#define TASK_ON_RQ_QUEUED       1
  89#define TASK_ON_RQ_MIGRATING    2
  90
  91extern __read_mostly int scheduler_running;
  92
  93extern unsigned long calc_load_update;
  94extern atomic_long_t calc_load_tasks;
  95
  96extern void calc_global_load_tick(struct rq *this_rq);
  97extern long calc_load_fold_active(struct rq *this_rq, long adjust);
  98
  99/*
 100 * Helpers for converting nanosecond timing to jiffy resolution
 101 */
 102#define NS_TO_JIFFIES(TIME)     ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
 103
 104/*
 105 * Increase resolution of nice-level calculations for 64-bit architectures.
 106 * The extra resolution improves shares distribution and load balancing of
 107 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
 108 * hierarchies, especially on larger systems. This is not a user-visible change
 109 * and does not change the user-interface for setting shares/weights.
 110 *
 111 * We increase resolution only if we have enough bits to allow this increased
 112 * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
 113 * are pretty high and the returns do not justify the increased costs.
 114 *
 115 * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
 116 * increase coverage and consistency always enable it on 64-bit platforms.
 117 */
 118#ifdef CONFIG_64BIT
 119# define NICE_0_LOAD_SHIFT      (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
 120# define scale_load(w)          ((w) << SCHED_FIXEDPOINT_SHIFT)
 121# define scale_load_down(w)     ((w) >> SCHED_FIXEDPOINT_SHIFT)
 122#else
 123# define NICE_0_LOAD_SHIFT      (SCHED_FIXEDPOINT_SHIFT)
 124# define scale_load(w)          (w)
 125# define scale_load_down(w)     (w)
 126#endif
 127
 128/*
 129 * Task weight (visible to users) and its load (invisible to users) have
 130 * independent resolution, but they should be well calibrated. We use
 131 * scale_load() and scale_load_down(w) to convert between them. The
 132 * following must be true:
 133 *
 134 *  scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD
 135 *
 136 */
 137#define NICE_0_LOAD             (1L << NICE_0_LOAD_SHIFT)
 138
 139/*
 140 * Single value that decides SCHED_DEADLINE internal math precision.
 141 * 10 -> just above 1us
 142 * 9  -> just above 0.5us
 143 */
 144#define DL_SCALE                10
 145
 146/*
 147 * Single value that denotes runtime == period, ie unlimited time.
 148 */
 149#define RUNTIME_INF             ((u64)~0ULL)
 150
 151static inline int idle_policy(int policy)
 152{
 153        return policy == SCHED_IDLE;
 154}
 155static inline int fair_policy(int policy)
 156{
 157        return policy == SCHED_NORMAL || policy == SCHED_BATCH;
 158}
 159
 160static inline int rt_policy(int policy)
 161{
 162        return policy == SCHED_FIFO || policy == SCHED_RR;
 163}
 164
 165static inline int dl_policy(int policy)
 166{
 167        return policy == SCHED_DEADLINE;
 168}
 169static inline bool valid_policy(int policy)
 170{
 171        return idle_policy(policy) || fair_policy(policy) ||
 172                rt_policy(policy) || dl_policy(policy);
 173}
 174
 175static inline int task_has_idle_policy(struct task_struct *p)
 176{
 177        return idle_policy(p->policy);
 178}
 179
 180static inline int task_has_rt_policy(struct task_struct *p)
 181{
 182        return rt_policy(p->policy);
 183}
 184
 185static inline int task_has_dl_policy(struct task_struct *p)
 186{
 187        return dl_policy(p->policy);
 188}
 189
 190#define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
 191
 192/*
 193 * !! For sched_setattr_nocheck() (kernel) only !!
 194 *
 195 * This is actually gross. :(
 196 *
 197 * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
 198 * tasks, but still be able to sleep. We need this on platforms that cannot
 199 * atomically change clock frequency. Remove once fast switching will be
 200 * available on such platforms.
 201 *
 202 * SUGOV stands for SchedUtil GOVernor.
 203 */
 204#define SCHED_FLAG_SUGOV        0x10000000
 205
 206static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se)
 207{
 208#ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
 209        return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
 210#else
 211        return false;
 212#endif
 213}
 214
 215/*
 216 * Tells if entity @a should preempt entity @b.
 217 */
 218static inline bool
 219dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
 220{
 221        return dl_entity_is_special(a) ||
 222               dl_time_before(a->deadline, b->deadline);
 223}
 224
 225/*
 226 * This is the priority-queue data structure of the RT scheduling class:
 227 */
 228struct rt_prio_array {
 229        DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
 230        struct list_head queue[MAX_RT_PRIO];
 231};
 232
 233struct rt_bandwidth {
 234        /* nests inside the rq lock: */
 235        raw_spinlock_t          rt_runtime_lock;
 236        ktime_t                 rt_period;
 237        u64                     rt_runtime;
 238        struct hrtimer          rt_period_timer;
 239        unsigned int            rt_period_active;
 240};
 241
 242void __dl_clear_params(struct task_struct *p);
 243
 244/*
 245 * To keep the bandwidth of -deadline tasks and groups under control
 246 * we need some place where:
 247 *  - store the maximum -deadline bandwidth of the system (the group);
 248 *  - cache the fraction of that bandwidth that is currently allocated.
 249 *
 250 * This is all done in the data structure below. It is similar to the
 251 * one used for RT-throttling (rt_bandwidth), with the main difference
 252 * that, since here we are only interested in admission control, we
 253 * do not decrease any runtime while the group "executes", neither we
 254 * need a timer to replenish it.
 255 *
 256 * With respect to SMP, the bandwidth is given on a per-CPU basis,
 257 * meaning that:
 258 *  - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU;
 259 *  - dl_total_bw array contains, in the i-eth element, the currently
 260 *    allocated bandwidth on the i-eth CPU.
 261 * Moreover, groups consume bandwidth on each CPU, while tasks only
 262 * consume bandwidth on the CPU they're running on.
 263 * Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw
 264 * that will be shown the next time the proc or cgroup controls will
 265 * be red. It on its turn can be changed by writing on its own
 266 * control.
 267 */
 268struct dl_bandwidth {
 269        raw_spinlock_t          dl_runtime_lock;
 270        u64                     dl_runtime;
 271        u64                     dl_period;
 272};
 273
 274static inline int dl_bandwidth_enabled(void)
 275{
 276        return sysctl_sched_rt_runtime >= 0;
 277}
 278
 279struct dl_bw {
 280        raw_spinlock_t          lock;
 281        u64                     bw;
 282        u64                     total_bw;
 283};
 284
 285static inline void __dl_update(struct dl_bw *dl_b, s64 bw);
 286
 287static inline
 288void __dl_sub(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
 289{
 290        dl_b->total_bw -= tsk_bw;
 291        __dl_update(dl_b, (s32)tsk_bw / cpus);
 292}
 293
 294static inline
 295void __dl_add(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
 296{
 297        dl_b->total_bw += tsk_bw;
 298        __dl_update(dl_b, -((s32)tsk_bw / cpus));
 299}
 300
 301static inline
 302bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)
 303{
 304        return dl_b->bw != -1 &&
 305               dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw;
 306}
 307
 308extern void dl_change_utilization(struct task_struct *p, u64 new_bw);
 309extern void init_dl_bw(struct dl_bw *dl_b);
 310extern int  sched_dl_global_validate(void);
 311extern void sched_dl_do_global(void);
 312extern int  sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
 313extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
 314extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
 315extern bool __checkparam_dl(const struct sched_attr *attr);
 316extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
 317extern int  dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
 318extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
 319extern bool dl_cpu_busy(unsigned int cpu);
 320
 321#ifdef CONFIG_CGROUP_SCHED
 322
 323#include <linux/cgroup.h>
 324#include <linux/psi.h>
 325
 326struct cfs_rq;
 327struct rt_rq;
 328
 329extern struct list_head task_groups;
 330
 331struct cfs_bandwidth {
 332#ifdef CONFIG_CFS_BANDWIDTH
 333        raw_spinlock_t          lock;
 334        ktime_t                 period;
 335        u64                     quota;
 336        u64                     runtime;
 337        s64                     hierarchical_quota;
 338
 339        u8                      idle;
 340        u8                      period_active;
 341        u8                      distribute_running;
 342        u8                      slack_started;
 343        struct hrtimer          period_timer;
 344        struct hrtimer          slack_timer;
 345        struct list_head        throttled_cfs_rq;
 346
 347        /* Statistics: */
 348        int                     nr_periods;
 349        int                     nr_throttled;
 350        u64                     throttled_time;
 351#endif
 352};
 353
 354/* Task group related information */
 355struct task_group {
 356        struct cgroup_subsys_state css;
 357
 358#ifdef CONFIG_FAIR_GROUP_SCHED
 359        /* schedulable entities of this group on each CPU */
 360        struct sched_entity     **se;
 361        /* runqueue "owned" by this group on each CPU */
 362        struct cfs_rq           **cfs_rq;
 363        unsigned long           shares;
 364
 365#ifdef  CONFIG_SMP
 366        /*
 367         * load_avg can be heavily contended at clock tick time, so put
 368         * it in its own cacheline separated from the fields above which
 369         * will also be accessed at each tick.
 370         */
 371        atomic_long_t           load_avg ____cacheline_aligned;
 372#endif
 373#endif
 374
 375#ifdef CONFIG_RT_GROUP_SCHED
 376        struct sched_rt_entity  **rt_se;
 377        struct rt_rq            **rt_rq;
 378
 379        struct rt_bandwidth     rt_bandwidth;
 380#endif
 381
 382        struct rcu_head         rcu;
 383        struct list_head        list;
 384
 385        struct task_group       *parent;
 386        struct list_head        siblings;
 387        struct list_head        children;
 388
 389#ifdef CONFIG_SCHED_AUTOGROUP
 390        struct autogroup        *autogroup;
 391#endif
 392
 393        struct cfs_bandwidth    cfs_bandwidth;
 394
 395#ifdef CONFIG_UCLAMP_TASK_GROUP
 396        /* The two decimal precision [%] value requested from user-space */
 397        unsigned int            uclamp_pct[UCLAMP_CNT];
 398        /* Clamp values requested for a task group */
 399        struct uclamp_se        uclamp_req[UCLAMP_CNT];
 400        /* Effective clamp values used for a task group */
 401        struct uclamp_se        uclamp[UCLAMP_CNT];
 402#endif
 403
 404};
 405
 406#ifdef CONFIG_FAIR_GROUP_SCHED
 407#define ROOT_TASK_GROUP_LOAD    NICE_0_LOAD
 408
 409/*
 410 * A weight of 0 or 1 can cause arithmetics problems.
 411 * A weight of a cfs_rq is the sum of weights of which entities
 412 * are queued on this cfs_rq, so a weight of a entity should not be
 413 * too large, so as the shares value of a task group.
 414 * (The default weight is 1024 - so there's no practical
 415 *  limitation from this.)
 416 */
 417#define MIN_SHARES              (1UL <<  1)
 418#define MAX_SHARES              (1UL << 18)
 419#endif
 420
 421typedef int (*tg_visitor)(struct task_group *, void *);
 422
 423extern int walk_tg_tree_from(struct task_group *from,
 424                             tg_visitor down, tg_visitor up, void *data);
 425
 426/*
 427 * Iterate the full tree, calling @down when first entering a node and @up when
 428 * leaving it for the final time.
 429 *
 430 * Caller must hold rcu_lock or sufficient equivalent.
 431 */
 432static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
 433{
 434        return walk_tg_tree_from(&root_task_group, down, up, data);
 435}
 436
 437extern int tg_nop(struct task_group *tg, void *data);
 438
 439extern void free_fair_sched_group(struct task_group *tg);
 440extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
 441extern void online_fair_sched_group(struct task_group *tg);
 442extern void unregister_fair_sched_group(struct task_group *tg);
 443extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
 444                        struct sched_entity *se, int cpu,
 445                        struct sched_entity *parent);
 446extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
 447
 448extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
 449extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
 450extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
 451
 452extern void free_rt_sched_group(struct task_group *tg);
 453extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
 454extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
 455                struct sched_rt_entity *rt_se, int cpu,
 456                struct sched_rt_entity *parent);
 457extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
 458extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
 459extern long sched_group_rt_runtime(struct task_group *tg);
 460extern long sched_group_rt_period(struct task_group *tg);
 461extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
 462
 463extern struct task_group *sched_create_group(struct task_group *parent);
 464extern void sched_online_group(struct task_group *tg,
 465                               struct task_group *parent);
 466extern void sched_destroy_group(struct task_group *tg);
 467extern void sched_offline_group(struct task_group *tg);
 468
 469extern void sched_move_task(struct task_struct *tsk);
 470
 471#ifdef CONFIG_FAIR_GROUP_SCHED
 472extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
 473
 474#ifdef CONFIG_SMP
 475extern void set_task_rq_fair(struct sched_entity *se,
 476                             struct cfs_rq *prev, struct cfs_rq *next);
 477#else /* !CONFIG_SMP */
 478static inline void set_task_rq_fair(struct sched_entity *se,
 479                             struct cfs_rq *prev, struct cfs_rq *next) { }
 480#endif /* CONFIG_SMP */
 481#endif /* CONFIG_FAIR_GROUP_SCHED */
 482
 483#else /* CONFIG_CGROUP_SCHED */
 484
 485struct cfs_bandwidth { };
 486
 487#endif  /* CONFIG_CGROUP_SCHED */
 488
 489/* CFS-related fields in a runqueue */
 490struct cfs_rq {
 491        struct load_weight      load;
 492        unsigned long           runnable_weight;
 493        unsigned int            nr_running;
 494        unsigned int            h_nr_running;      /* SCHED_{NORMAL,BATCH,IDLE} */
 495        unsigned int            idle_h_nr_running; /* SCHED_IDLE */
 496
 497        u64                     exec_clock;
 498        u64                     min_vruntime;
 499#ifndef CONFIG_64BIT
 500        u64                     min_vruntime_copy;
 501#endif
 502
 503        struct rb_root_cached   tasks_timeline;
 504
 505        /*
 506         * 'curr' points to currently running entity on this cfs_rq.
 507         * It is set to NULL otherwise (i.e when none are currently running).
 508         */
 509        struct sched_entity     *curr;
 510        struct sched_entity     *next;
 511        struct sched_entity     *last;
 512        struct sched_entity     *skip;
 513
 514#ifdef  CONFIG_SCHED_DEBUG
 515        unsigned int            nr_spread_over;
 516#endif
 517
 518#ifdef CONFIG_SMP
 519        /*
 520         * CFS load tracking
 521         */
 522        struct sched_avg        avg;
 523#ifndef CONFIG_64BIT
 524        u64                     load_last_update_time_copy;
 525#endif
 526        struct {
 527                raw_spinlock_t  lock ____cacheline_aligned;
 528                int             nr;
 529                unsigned long   load_avg;
 530                unsigned long   util_avg;
 531                unsigned long   runnable_sum;
 532        } removed;
 533
 534#ifdef CONFIG_FAIR_GROUP_SCHED
 535        unsigned long           tg_load_avg_contrib;
 536        long                    propagate;
 537        long                    prop_runnable_sum;
 538
 539        /*
 540         *   h_load = weight * f(tg)
 541         *
 542         * Where f(tg) is the recursive weight fraction assigned to
 543         * this group.
 544         */
 545        unsigned long           h_load;
 546        u64                     last_h_load_update;
 547        struct sched_entity     *h_load_next;
 548#endif /* CONFIG_FAIR_GROUP_SCHED */
 549#endif /* CONFIG_SMP */
 550
 551#ifdef CONFIG_FAIR_GROUP_SCHED
 552        struct rq               *rq;    /* CPU runqueue to which this cfs_rq is attached */
 553
 554        /*
 555         * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
 556         * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
 557         * (like users, containers etc.)
 558         *
 559         * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
 560         * This list is used during load balance.
 561         */
 562        int                     on_list;
 563        struct list_head        leaf_cfs_rq_list;
 564        struct task_group       *tg;    /* group that "owns" this runqueue */
 565
 566#ifdef CONFIG_CFS_BANDWIDTH
 567        int                     runtime_enabled;
 568        s64                     runtime_remaining;
 569
 570        u64                     throttled_clock;
 571        u64                     throttled_clock_task;
 572        u64                     throttled_clock_task_time;
 573        int                     throttled;
 574        int                     throttle_count;
 575        struct list_head        throttled_list;
 576#endif /* CONFIG_CFS_BANDWIDTH */
 577#endif /* CONFIG_FAIR_GROUP_SCHED */
 578};
 579
 580static inline int rt_bandwidth_enabled(void)
 581{
 582        return sysctl_sched_rt_runtime >= 0;
 583}
 584
 585/* RT IPI pull logic requires IRQ_WORK */
 586#if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
 587# define HAVE_RT_PUSH_IPI
 588#endif
 589
 590/* Real-Time classes' related field in a runqueue: */
 591struct rt_rq {
 592        struct rt_prio_array    active;
 593        unsigned int            rt_nr_running;
 594        unsigned int            rr_nr_running;
 595#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
 596        struct {
 597                int             curr; /* highest queued rt task prio */
 598#ifdef CONFIG_SMP
 599                int             next; /* next highest */
 600#endif
 601        } highest_prio;
 602#endif
 603#ifdef CONFIG_SMP
 604        unsigned long           rt_nr_migratory;
 605        unsigned long           rt_nr_total;
 606        int                     overloaded;
 607        struct plist_head       pushable_tasks;
 608
 609#endif /* CONFIG_SMP */
 610        int                     rt_queued;
 611
 612        int                     rt_throttled;
 613        u64                     rt_time;
 614        u64                     rt_runtime;
 615        /* Nests inside the rq lock: */
 616        raw_spinlock_t          rt_runtime_lock;
 617
 618#ifdef CONFIG_RT_GROUP_SCHED
 619        unsigned long           rt_nr_boosted;
 620
 621        struct rq               *rq;
 622        struct task_group       *tg;
 623#endif
 624};
 625
 626static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
 627{
 628        return rt_rq->rt_queued && rt_rq->rt_nr_running;
 629}
 630
 631/* Deadline class' related fields in a runqueue */
 632struct dl_rq {
 633        /* runqueue is an rbtree, ordered by deadline */
 634        struct rb_root_cached   root;
 635
 636        unsigned long           dl_nr_running;
 637
 638#ifdef CONFIG_SMP
 639        /*
 640         * Deadline values of the currently executing and the
 641         * earliest ready task on this rq. Caching these facilitates
 642         * the decision whether or not a ready but not running task
 643         * should migrate somewhere else.
 644         */
 645        struct {
 646                u64             curr;
 647                u64             next;
 648        } earliest_dl;
 649
 650        unsigned long           dl_nr_migratory;
 651        int                     overloaded;
 652
 653        /*
 654         * Tasks on this rq that can be pushed away. They are kept in
 655         * an rb-tree, ordered by tasks' deadlines, with caching
 656         * of the leftmost (earliest deadline) element.
 657         */
 658        struct rb_root_cached   pushable_dl_tasks_root;
 659#else
 660        struct dl_bw            dl_bw;
 661#endif
 662        /*
 663         * "Active utilization" for this runqueue: increased when a
 664         * task wakes up (becomes TASK_RUNNING) and decreased when a
 665         * task blocks
 666         */
 667        u64                     running_bw;
 668
 669        /*
 670         * Utilization of the tasks "assigned" to this runqueue (including
 671         * the tasks that are in runqueue and the tasks that executed on this
 672         * CPU and blocked). Increased when a task moves to this runqueue, and
 673         * decreased when the task moves away (migrates, changes scheduling
 674         * policy, or terminates).
 675         * This is needed to compute the "inactive utilization" for the
 676         * runqueue (inactive utilization = this_bw - running_bw).
 677         */
 678        u64                     this_bw;
 679        u64                     extra_bw;
 680
 681        /*
 682         * Inverse of the fraction of CPU utilization that can be reclaimed
 683         * by the GRUB algorithm.
 684         */
 685        u64                     bw_ratio;
 686};
 687
 688#ifdef CONFIG_FAIR_GROUP_SCHED
 689/* An entity is a task if it doesn't "own" a runqueue */
 690#define entity_is_task(se)      (!se->my_q)
 691#else
 692#define entity_is_task(se)      1
 693#endif
 694
 695#ifdef CONFIG_SMP
 696/*
 697 * XXX we want to get rid of these helpers and use the full load resolution.
 698 */
 699static inline long se_weight(struct sched_entity *se)
 700{
 701        return scale_load_down(se->load.weight);
 702}
 703
 704static inline long se_runnable(struct sched_entity *se)
 705{
 706        return scale_load_down(se->runnable_weight);
 707}
 708
 709static inline bool sched_asym_prefer(int a, int b)
 710{
 711        return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
 712}
 713
 714struct perf_domain {
 715        struct em_perf_domain *em_pd;
 716        struct perf_domain *next;
 717        struct rcu_head rcu;
 718};
 719
 720/* Scheduling group status flags */
 721#define SG_OVERLOAD             0x1 /* More than one runnable task on a CPU. */
 722#define SG_OVERUTILIZED         0x2 /* One or more CPUs are over-utilized. */
 723
 724/*
 725 * We add the notion of a root-domain which will be used to define per-domain
 726 * variables. Each exclusive cpuset essentially defines an island domain by
 727 * fully partitioning the member CPUs from any other cpuset. Whenever a new
 728 * exclusive cpuset is created, we also create and attach a new root-domain
 729 * object.
 730 *
 731 */
 732struct root_domain {
 733        atomic_t                refcount;
 734        atomic_t                rto_count;
 735        struct rcu_head         rcu;
 736        cpumask_var_t           span;
 737        cpumask_var_t           online;
 738
 739        /*
 740         * Indicate pullable load on at least one CPU, e.g:
 741         * - More than one runnable task
 742         * - Running task is misfit
 743         */
 744        int                     overload;
 745
 746        /* Indicate one or more cpus over-utilized (tipping point) */
 747        int                     overutilized;
 748
 749        /*
 750         * The bit corresponding to a CPU gets set here if such CPU has more
 751         * than one runnable -deadline task (as it is below for RT tasks).
 752         */
 753        cpumask_var_t           dlo_mask;
 754        atomic_t                dlo_count;
 755        struct dl_bw            dl_bw;
 756        struct cpudl            cpudl;
 757
 758#ifdef HAVE_RT_PUSH_IPI
 759        /*
 760         * For IPI pull requests, loop across the rto_mask.
 761         */
 762        struct irq_work         rto_push_work;
 763        raw_spinlock_t          rto_lock;
 764        /* These are only updated and read within rto_lock */
 765        int                     rto_loop;
 766        int                     rto_cpu;
 767        /* These atomics are updated outside of a lock */
 768        atomic_t                rto_loop_next;
 769        atomic_t                rto_loop_start;
 770#endif
 771        /*
 772         * The "RT overload" flag: it gets set if a CPU has more than
 773         * one runnable RT task.
 774         */
 775        cpumask_var_t           rto_mask;
 776        struct cpupri           cpupri;
 777
 778        unsigned long           max_cpu_capacity;
 779
 780        /*
 781         * NULL-terminated list of performance domains intersecting with the
 782         * CPUs of the rd. Protected by RCU.
 783         */
 784        struct perf_domain __rcu *pd;
 785};
 786
 787extern void init_defrootdomain(void);
 788extern int sched_init_domains(const struct cpumask *cpu_map);
 789extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
 790extern void sched_get_rd(struct root_domain *rd);
 791extern void sched_put_rd(struct root_domain *rd);
 792
 793#ifdef HAVE_RT_PUSH_IPI
 794extern void rto_push_irq_work_func(struct irq_work *work);
 795#endif
 796#endif /* CONFIG_SMP */
 797
 798#ifdef CONFIG_UCLAMP_TASK
 799/*
 800 * struct uclamp_bucket - Utilization clamp bucket
 801 * @value: utilization clamp value for tasks on this clamp bucket
 802 * @tasks: number of RUNNABLE tasks on this clamp bucket
 803 *
 804 * Keep track of how many tasks are RUNNABLE for a given utilization
 805 * clamp value.
 806 */
 807struct uclamp_bucket {
 808        unsigned long value : bits_per(SCHED_CAPACITY_SCALE);
 809        unsigned long tasks : BITS_PER_LONG - bits_per(SCHED_CAPACITY_SCALE);
 810};
 811
 812/*
 813 * struct uclamp_rq - rq's utilization clamp
 814 * @value: currently active clamp values for a rq
 815 * @bucket: utilization clamp buckets affecting a rq
 816 *
 817 * Keep track of RUNNABLE tasks on a rq to aggregate their clamp values.
 818 * A clamp value is affecting a rq when there is at least one task RUNNABLE
 819 * (or actually running) with that value.
 820 *
 821 * There are up to UCLAMP_CNT possible different clamp values, currently there
 822 * are only two: minimum utilization and maximum utilization.
 823 *
 824 * All utilization clamping values are MAX aggregated, since:
 825 * - for util_min: we want to run the CPU at least at the max of the minimum
 826 *   utilization required by its currently RUNNABLE tasks.
 827 * - for util_max: we want to allow the CPU to run up to the max of the
 828 *   maximum utilization allowed by its currently RUNNABLE tasks.
 829 *
 830 * Since on each system we expect only a limited number of different
 831 * utilization clamp values (UCLAMP_BUCKETS), use a simple array to track
 832 * the metrics required to compute all the per-rq utilization clamp values.
 833 */
 834struct uclamp_rq {
 835        unsigned int value;
 836        struct uclamp_bucket bucket[UCLAMP_BUCKETS];
 837};
 838#endif /* CONFIG_UCLAMP_TASK */
 839
 840/*
 841 * This is the main, per-CPU runqueue data structure.
 842 *
 843 * Locking rule: those places that want to lock multiple runqueues
 844 * (such as the load balancing or the thread migration code), lock
 845 * acquire operations must be ordered by ascending &runqueue.
 846 */
 847struct rq {
 848        /* runqueue lock: */
 849        raw_spinlock_t          lock;
 850
 851        /*
 852         * nr_running and cpu_load should be in the same cacheline because
 853         * remote CPUs use both these fields when doing load calculation.
 854         */
 855        unsigned int            nr_running;
 856#ifdef CONFIG_NUMA_BALANCING
 857        unsigned int            nr_numa_running;
 858        unsigned int            nr_preferred_running;
 859        unsigned int            numa_migrate_on;
 860#endif
 861#ifdef CONFIG_NO_HZ_COMMON
 862#ifdef CONFIG_SMP
 863        unsigned long           last_load_update_tick;
 864        unsigned long           last_blocked_load_update_tick;
 865        unsigned int            has_blocked_load;
 866#endif /* CONFIG_SMP */
 867        unsigned int            nohz_tick_stopped;
 868        atomic_t nohz_flags;
 869#endif /* CONFIG_NO_HZ_COMMON */
 870
 871        unsigned long           nr_load_updates;
 872        u64                     nr_switches;
 873
 874#ifdef CONFIG_UCLAMP_TASK
 875        /* Utilization clamp values based on CPU's RUNNABLE tasks */
 876        struct uclamp_rq        uclamp[UCLAMP_CNT] ____cacheline_aligned;
 877        unsigned int            uclamp_flags;
 878#define UCLAMP_FLAG_IDLE 0x01
 879#endif
 880
 881        struct cfs_rq           cfs;
 882        struct rt_rq            rt;
 883        struct dl_rq            dl;
 884
 885#ifdef CONFIG_FAIR_GROUP_SCHED
 886        /* list of leaf cfs_rq on this CPU: */
 887        struct list_head        leaf_cfs_rq_list;
 888        struct list_head        *tmp_alone_branch;
 889#endif /* CONFIG_FAIR_GROUP_SCHED */
 890
 891        /*
 892         * This is part of a global counter where only the total sum
 893         * over all CPUs matters. A task can increase this counter on
 894         * one CPU and if it got migrated afterwards it may decrease
 895         * it on another CPU. Always updated under the runqueue lock:
 896         */
 897        unsigned long           nr_uninterruptible;
 898
 899        struct task_struct      *curr;
 900        struct task_struct      *idle;
 901        struct task_struct      *stop;
 902        unsigned long           next_balance;
 903        struct mm_struct        *prev_mm;
 904
 905        unsigned int            clock_update_flags;
 906        u64                     clock;
 907        /* Ensure that all clocks are in the same cache line */
 908        u64                     clock_task ____cacheline_aligned;
 909        u64                     clock_pelt;
 910        unsigned long           lost_idle_time;
 911
 912        atomic_t                nr_iowait;
 913
 914#ifdef CONFIG_MEMBARRIER
 915        int membarrier_state;
 916#endif
 917
 918#ifdef CONFIG_SMP
 919        struct root_domain              *rd;
 920        struct sched_domain __rcu       *sd;
 921
 922        unsigned long           cpu_capacity;
 923        unsigned long           cpu_capacity_orig;
 924
 925        struct callback_head    *balance_callback;
 926
 927        unsigned char           idle_balance;
 928
 929        unsigned long           misfit_task_load;
 930
 931        /* For active balancing */
 932        int                     active_balance;
 933        int                     push_cpu;
 934        struct cpu_stop_work    active_balance_work;
 935
 936        /* CPU of this runqueue: */
 937        int                     cpu;
 938        int                     online;
 939
 940        struct list_head cfs_tasks;
 941
 942        struct sched_avg        avg_rt;
 943        struct sched_avg        avg_dl;
 944#ifdef CONFIG_HAVE_SCHED_AVG_IRQ
 945        struct sched_avg        avg_irq;
 946#endif
 947        u64                     idle_stamp;
 948        u64                     avg_idle;
 949
 950        /* This is used to determine avg_idle's max value */
 951        u64                     max_idle_balance_cost;
 952#endif
 953
 954#ifdef CONFIG_IRQ_TIME_ACCOUNTING
 955        u64                     prev_irq_time;
 956#endif
 957#ifdef CONFIG_PARAVIRT
 958        u64                     prev_steal_time;
 959#endif
 960#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
 961        u64                     prev_steal_time_rq;
 962#endif
 963
 964        /* calc_load related fields */
 965        unsigned long           calc_load_update;
 966        long                    calc_load_active;
 967
 968#ifdef CONFIG_SCHED_HRTICK
 969#ifdef CONFIG_SMP
 970        int                     hrtick_csd_pending;
 971        call_single_data_t      hrtick_csd;
 972#endif
 973        struct hrtimer          hrtick_timer;
 974#endif
 975
 976#ifdef CONFIG_SCHEDSTATS
 977        /* latency stats */
 978        struct sched_info       rq_sched_info;
 979        unsigned long long      rq_cpu_time;
 980        /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
 981
 982        /* sys_sched_yield() stats */
 983        unsigned int            yld_count;
 984
 985        /* schedule() stats */
 986        unsigned int            sched_count;
 987        unsigned int            sched_goidle;
 988
 989        /* try_to_wake_up() stats */
 990        unsigned int            ttwu_count;
 991        unsigned int            ttwu_local;
 992#endif
 993
 994#ifdef CONFIG_SMP
 995        struct llist_head       wake_list;
 996#endif
 997
 998#ifdef CONFIG_CPU_IDLE
 999        /* Must be inspected within a rcu lock section */
1000        struct cpuidle_state    *idle_state;
1001#endif
1002};
1003
1004#ifdef CONFIG_FAIR_GROUP_SCHED
1005
1006/* CPU runqueue to which this cfs_rq is attached */
1007static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1008{
1009        return cfs_rq->rq;
1010}
1011
1012#else
1013
1014static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
1015{
1016        return container_of(cfs_rq, struct rq, cfs);
1017}
1018#endif
1019
1020static inline int cpu_of(struct rq *rq)
1021{
1022#ifdef CONFIG_SMP
1023        return rq->cpu;
1024#else
1025        return 0;
1026#endif
1027}
1028
1029
1030#ifdef CONFIG_SCHED_SMT
1031extern void __update_idle_core(struct rq *rq);
1032
1033static inline void update_idle_core(struct rq *rq)
1034{
1035        if (static_branch_unlikely(&sched_smt_present))
1036                __update_idle_core(rq);
1037}
1038
1039#else
1040static inline void update_idle_core(struct rq *rq) { }
1041#endif
1042
1043DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
1044
1045#define cpu_rq(cpu)             (&per_cpu(runqueues, (cpu)))
1046#define this_rq()               this_cpu_ptr(&runqueues)
1047#define task_rq(p)              cpu_rq(task_cpu(p))
1048#define cpu_curr(cpu)           (cpu_rq(cpu)->curr)
1049#define raw_rq()                raw_cpu_ptr(&runqueues)
1050
1051extern void update_rq_clock(struct rq *rq);
1052
1053static inline u64 __rq_clock_broken(struct rq *rq)
1054{
1055        return READ_ONCE(rq->clock);
1056}
1057
1058/*
1059 * rq::clock_update_flags bits
1060 *
1061 * %RQCF_REQ_SKIP - will request skipping of clock update on the next
1062 *  call to __schedule(). This is an optimisation to avoid
1063 *  neighbouring rq clock updates.
1064 *
1065 * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
1066 *  in effect and calls to update_rq_clock() are being ignored.
1067 *
1068 * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
1069 *  made to update_rq_clock() since the last time rq::lock was pinned.
1070 *
1071 * If inside of __schedule(), clock_update_flags will have been
1072 * shifted left (a left shift is a cheap operation for the fast path
1073 * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
1074 *
1075 *      if (rq-clock_update_flags >= RQCF_UPDATED)
1076 *
1077 * to check if %RQCF_UPADTED is set. It'll never be shifted more than
1078 * one position though, because the next rq_unpin_lock() will shift it
1079 * back.
1080 */
1081#define RQCF_REQ_SKIP           0x01
1082#define RQCF_ACT_SKIP           0x02
1083#define RQCF_UPDATED            0x04
1084
1085static inline void assert_clock_updated(struct rq *rq)
1086{
1087        /*
1088         * The only reason for not seeing a clock update since the
1089         * last rq_pin_lock() is if we're currently skipping updates.
1090         */
1091        SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
1092}
1093
1094static inline u64 rq_clock(struct rq *rq)
1095{
1096        lockdep_assert_held(&rq->lock);
1097        assert_clock_updated(rq);
1098
1099        return rq->clock;
1100}
1101
1102static inline u64 rq_clock_task(struct rq *rq)
1103{
1104        lockdep_assert_held(&rq->lock);
1105        assert_clock_updated(rq);
1106
1107        return rq->clock_task;
1108}
1109
1110static inline void rq_clock_skip_update(struct rq *rq)
1111{
1112        lockdep_assert_held(&rq->lock);
1113        rq->clock_update_flags |= RQCF_REQ_SKIP;
1114}
1115
1116/*
1117 * See rt task throttling, which is the only time a skip
1118 * request is cancelled.
1119 */
1120static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1121{
1122        lockdep_assert_held(&rq->lock);
1123        rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1124}
1125
1126struct rq_flags {
1127        unsigned long flags;
1128        struct pin_cookie cookie;
1129#ifdef CONFIG_SCHED_DEBUG
1130        /*
1131         * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1132         * current pin context is stashed here in case it needs to be
1133         * restored in rq_repin_lock().
1134         */
1135        unsigned int clock_update_flags;
1136#endif
1137};
1138
1139static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1140{
1141        rf->cookie = lockdep_pin_lock(&rq->lock);
1142
1143#ifdef CONFIG_SCHED_DEBUG
1144        rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1145        rf->clock_update_flags = 0;
1146#endif
1147}
1148
1149static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1150{
1151#ifdef CONFIG_SCHED_DEBUG
1152        if (rq->clock_update_flags > RQCF_ACT_SKIP)
1153                rf->clock_update_flags = RQCF_UPDATED;
1154#endif
1155
1156        lockdep_unpin_lock(&rq->lock, rf->cookie);
1157}
1158
1159static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1160{
1161        lockdep_repin_lock(&rq->lock, rf->cookie);
1162
1163#ifdef CONFIG_SCHED_DEBUG
1164        /*
1165         * Restore the value we stashed in @rf for this pin context.
1166         */
1167        rq->clock_update_flags |= rf->clock_update_flags;
1168#endif
1169}
1170
1171struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1172        __acquires(rq->lock);
1173
1174struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1175        __acquires(p->pi_lock)
1176        __acquires(rq->lock);
1177
1178static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1179        __releases(rq->lock)
1180{
1181        rq_unpin_lock(rq, rf);
1182        raw_spin_unlock(&rq->lock);
1183}
1184
1185static inline void
1186task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1187        __releases(rq->lock)
1188        __releases(p->pi_lock)
1189{
1190        rq_unpin_lock(rq, rf);
1191        raw_spin_unlock(&rq->lock);
1192        raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1193}
1194
1195static inline void
1196rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1197        __acquires(rq->lock)
1198{
1199        raw_spin_lock_irqsave(&rq->lock, rf->flags);
1200        rq_pin_lock(rq, rf);
1201}
1202
1203static inline void
1204rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1205        __acquires(rq->lock)
1206{
1207        raw_spin_lock_irq(&rq->lock);
1208        rq_pin_lock(rq, rf);
1209}
1210
1211static inline void
1212rq_lock(struct rq *rq, struct rq_flags *rf)
1213        __acquires(rq->lock)
1214{
1215        raw_spin_lock(&rq->lock);
1216        rq_pin_lock(rq, rf);
1217}
1218
1219static inline void
1220rq_relock(struct rq *rq, struct rq_flags *rf)
1221        __acquires(rq->lock)
1222{
1223        raw_spin_lock(&rq->lock);
1224        rq_repin_lock(rq, rf);
1225}
1226
1227static inline void
1228rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1229        __releases(rq->lock)
1230{
1231        rq_unpin_lock(rq, rf);
1232        raw_spin_unlock_irqrestore(&rq->lock, rf->flags);
1233}
1234
1235static inline void
1236rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1237        __releases(rq->lock)
1238{
1239        rq_unpin_lock(rq, rf);
1240        raw_spin_unlock_irq(&rq->lock);
1241}
1242
1243static inline void
1244rq_unlock(struct rq *rq, struct rq_flags *rf)
1245        __releases(rq->lock)
1246{
1247        rq_unpin_lock(rq, rf);
1248        raw_spin_unlock(&rq->lock);
1249}
1250
1251static inline struct rq *
1252this_rq_lock_irq(struct rq_flags *rf)
1253        __acquires(rq->lock)
1254{
1255        struct rq *rq;
1256
1257        local_irq_disable();
1258        rq = this_rq();
1259        rq_lock(rq, rf);
1260        return rq;
1261}
1262
1263#ifdef CONFIG_NUMA
1264enum numa_topology_type {
1265        NUMA_DIRECT,
1266        NUMA_GLUELESS_MESH,
1267        NUMA_BACKPLANE,
1268};
1269extern enum numa_topology_type sched_numa_topology_type;
1270extern int sched_max_numa_distance;
1271extern bool find_numa_distance(int distance);
1272extern void sched_init_numa(void);
1273extern void sched_domains_numa_masks_set(unsigned int cpu);
1274extern void sched_domains_numa_masks_clear(unsigned int cpu);
1275extern int sched_numa_find_closest(const struct cpumask *cpus, int cpu);
1276#else
1277static inline void sched_init_numa(void) { }
1278static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
1279static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1280static inline int sched_numa_find_closest(const struct cpumask *cpus, int cpu)
1281{
1282        return nr_cpu_ids;
1283}
1284#endif
1285
1286#ifdef CONFIG_NUMA_BALANCING
1287/* The regions in numa_faults array from task_struct */
1288enum numa_faults_stats {
1289        NUMA_MEM = 0,
1290        NUMA_CPU,
1291        NUMA_MEMBUF,
1292        NUMA_CPUBUF
1293};
1294extern void sched_setnuma(struct task_struct *p, int node);
1295extern int migrate_task_to(struct task_struct *p, int cpu);
1296extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1297                        int cpu, int scpu);
1298extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1299#else
1300static inline void
1301init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1302{
1303}
1304#endif /* CONFIG_NUMA_BALANCING */
1305
1306#ifdef CONFIG_SMP
1307
1308static inline void
1309queue_balance_callback(struct rq *rq,
1310                       struct callback_head *head,
1311                       void (*func)(struct rq *rq))
1312{
1313        lockdep_assert_held(&rq->lock);
1314
1315        if (unlikely(head->next))
1316                return;
1317
1318        head->func = (void (*)(struct callback_head *))func;
1319        head->next = rq->balance_callback;
1320        rq->balance_callback = head;
1321}
1322
1323extern void sched_ttwu_pending(void);
1324
1325#define rcu_dereference_check_sched_domain(p) \
1326        rcu_dereference_check((p), \
1327                              lockdep_is_held(&sched_domains_mutex))
1328
1329/*
1330 * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1331 * See destroy_sched_domains: call_rcu for details.
1332 *
1333 * The domain tree of any CPU may only be accessed from within
1334 * preempt-disabled sections.
1335 */
1336#define for_each_domain(cpu, __sd) \
1337        for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1338                        __sd; __sd = __sd->parent)
1339
1340#define for_each_lower_domain(sd) for (; sd; sd = sd->child)
1341
1342/**
1343 * highest_flag_domain - Return highest sched_domain containing flag.
1344 * @cpu:        The CPU whose highest level of sched domain is to
1345 *              be returned.
1346 * @flag:       The flag to check for the highest sched_domain
1347 *              for the given CPU.
1348 *
1349 * Returns the highest sched_domain of a CPU which contains the given flag.
1350 */
1351static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1352{
1353        struct sched_domain *sd, *hsd = NULL;
1354
1355        for_each_domain(cpu, sd) {
1356                if (!(sd->flags & flag))
1357                        break;
1358                hsd = sd;
1359        }
1360
1361        return hsd;
1362}
1363
1364static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1365{
1366        struct sched_domain *sd;
1367
1368        for_each_domain(cpu, sd) {
1369                if (sd->flags & flag)
1370                        break;
1371        }
1372
1373        return sd;
1374}
1375
1376DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc);
1377DECLARE_PER_CPU(int, sd_llc_size);
1378DECLARE_PER_CPU(int, sd_llc_id);
1379DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared);
1380DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa);
1381DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing);
1382DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity);
1383extern struct static_key_false sched_asym_cpucapacity;
1384
1385struct sched_group_capacity {
1386        atomic_t                ref;
1387        /*
1388         * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1389         * for a single CPU.
1390         */
1391        unsigned long           capacity;
1392        unsigned long           min_capacity;           /* Min per-CPU capacity in group */
1393        unsigned long           max_capacity;           /* Max per-CPU capacity in group */
1394        unsigned long           next_update;
1395        int                     imbalance;              /* XXX unrelated to capacity but shared group state */
1396
1397#ifdef CONFIG_SCHED_DEBUG
1398        int                     id;
1399#endif
1400
1401        unsigned long           cpumask[0];             /* Balance mask */
1402};
1403
1404struct sched_group {
1405        struct sched_group      *next;                  /* Must be a circular list */
1406        atomic_t                ref;
1407
1408        unsigned int            group_weight;
1409        struct sched_group_capacity *sgc;
1410        int                     asym_prefer_cpu;        /* CPU of highest priority in group */
1411
1412        /*
1413         * The CPUs this group covers.
1414         *
1415         * NOTE: this field is variable length. (Allocated dynamically
1416         * by attaching extra space to the end of the structure,
1417         * depending on how many CPUs the kernel has booted up with)
1418         */
1419        unsigned long           cpumask[0];
1420};
1421
1422static inline struct cpumask *sched_group_span(struct sched_group *sg)
1423{
1424        return to_cpumask(sg->cpumask);
1425}
1426
1427/*
1428 * See build_balance_mask().
1429 */
1430static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1431{
1432        return to_cpumask(sg->sgc->cpumask);
1433}
1434
1435/**
1436 * group_first_cpu - Returns the first CPU in the cpumask of a sched_group.
1437 * @group: The group whose first CPU is to be returned.
1438 */
1439static inline unsigned int group_first_cpu(struct sched_group *group)
1440{
1441        return cpumask_first(sched_group_span(group));
1442}
1443
1444extern int group_balance_cpu(struct sched_group *sg);
1445
1446#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
1447void register_sched_domain_sysctl(void);
1448void dirty_sched_domain_sysctl(int cpu);
1449void unregister_sched_domain_sysctl(void);
1450#else
1451static inline void register_sched_domain_sysctl(void)
1452{
1453}
1454static inline void dirty_sched_domain_sysctl(int cpu)
1455{
1456}
1457static inline void unregister_sched_domain_sysctl(void)
1458{
1459}
1460#endif
1461
1462extern int newidle_balance(struct rq *this_rq, struct rq_flags *rf);
1463
1464#else
1465
1466static inline void sched_ttwu_pending(void) { }
1467
1468static inline int newidle_balance(struct rq *this_rq, struct rq_flags *rf) { return 0; }
1469
1470#endif /* CONFIG_SMP */
1471
1472#include "stats.h"
1473#include "autogroup.h"
1474
1475#ifdef CONFIG_CGROUP_SCHED
1476
1477/*
1478 * Return the group to which this tasks belongs.
1479 *
1480 * We cannot use task_css() and friends because the cgroup subsystem
1481 * changes that value before the cgroup_subsys::attach() method is called,
1482 * therefore we cannot pin it and might observe the wrong value.
1483 *
1484 * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
1485 * core changes this before calling sched_move_task().
1486 *
1487 * Instead we use a 'copy' which is updated from sched_move_task() while
1488 * holding both task_struct::pi_lock and rq::lock.
1489 */
1490static inline struct task_group *task_group(struct task_struct *p)
1491{
1492        return p->sched_task_group;
1493}
1494
1495/* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
1496static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
1497{
1498#if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
1499        struct task_group *tg = task_group(p);
1500#endif
1501
1502#ifdef CONFIG_FAIR_GROUP_SCHED
1503        set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
1504        p->se.cfs_rq = tg->cfs_rq[cpu];
1505        p->se.parent = tg->se[cpu];
1506#endif
1507
1508#ifdef CONFIG_RT_GROUP_SCHED
1509        p->rt.rt_rq  = tg->rt_rq[cpu];
1510        p->rt.parent = tg->rt_se[cpu];
1511#endif
1512}
1513
1514#else /* CONFIG_CGROUP_SCHED */
1515
1516static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
1517static inline struct task_group *task_group(struct task_struct *p)
1518{
1519        return NULL;
1520}
1521
1522#endif /* CONFIG_CGROUP_SCHED */
1523
1524static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
1525{
1526        set_task_rq(p, cpu);
1527#ifdef CONFIG_SMP
1528        /*
1529         * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
1530         * successfully executed on another CPU. We must ensure that updates of
1531         * per-task data have been completed by this moment.
1532         */
1533        smp_wmb();
1534#ifdef CONFIG_THREAD_INFO_IN_TASK
1535        WRITE_ONCE(p->cpu, cpu);
1536#else
1537        WRITE_ONCE(task_thread_info(p)->cpu, cpu);
1538#endif
1539        p->wake_cpu = cpu;
1540#endif
1541}
1542
1543/*
1544 * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1545 */
1546#ifdef CONFIG_SCHED_DEBUG
1547# include <linux/static_key.h>
1548# define const_debug __read_mostly
1549#else
1550# define const_debug const
1551#endif
1552
1553#define SCHED_FEAT(name, enabled)       \
1554        __SCHED_FEAT_##name ,
1555
1556enum {
1557#include "features.h"
1558        __SCHED_FEAT_NR,
1559};
1560
1561#undef SCHED_FEAT
1562
1563#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_JUMP_LABEL)
1564
1565/*
1566 * To support run-time toggling of sched features, all the translation units
1567 * (but core.c) reference the sysctl_sched_features defined in core.c.
1568 */
1569extern const_debug unsigned int sysctl_sched_features;
1570
1571#define SCHED_FEAT(name, enabled)                                       \
1572static __always_inline bool static_branch_##name(struct static_key *key) \
1573{                                                                       \
1574        return static_key_##enabled(key);                               \
1575}
1576
1577#include "features.h"
1578#undef SCHED_FEAT
1579
1580extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
1581#define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
1582
1583#else /* !(SCHED_DEBUG && CONFIG_JUMP_LABEL) */
1584
1585/*
1586 * Each translation unit has its own copy of sysctl_sched_features to allow
1587 * constants propagation at compile time and compiler optimization based on
1588 * features default.
1589 */
1590#define SCHED_FEAT(name, enabled)       \
1591        (1UL << __SCHED_FEAT_##name) * enabled |
1592static const_debug __maybe_unused unsigned int sysctl_sched_features =
1593#include "features.h"
1594        0;
1595#undef SCHED_FEAT
1596
1597#define sched_feat(x) !!(sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1598
1599#endif /* SCHED_DEBUG && CONFIG_JUMP_LABEL */
1600
1601extern struct static_key_false sched_numa_balancing;
1602extern struct static_key_false sched_schedstats;
1603
1604static inline u64 global_rt_period(void)
1605{
1606        return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
1607}
1608
1609static inline u64 global_rt_runtime(void)
1610{
1611        if (sysctl_sched_rt_runtime < 0)
1612                return RUNTIME_INF;
1613
1614        return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
1615}
1616
1617static inline int task_current(struct rq *rq, struct task_struct *p)
1618{
1619        return rq->curr == p;
1620}
1621
1622static inline int task_running(struct rq *rq, struct task_struct *p)
1623{
1624#ifdef CONFIG_SMP
1625        return p->on_cpu;
1626#else
1627        return task_current(rq, p);
1628#endif
1629}
1630
1631static inline int task_on_rq_queued(struct task_struct *p)
1632{
1633        return p->on_rq == TASK_ON_RQ_QUEUED;
1634}
1635
1636static inline int task_on_rq_migrating(struct task_struct *p)
1637{
1638        return READ_ONCE(p->on_rq) == TASK_ON_RQ_MIGRATING;
1639}
1640
1641/*
1642 * wake flags
1643 */
1644#define WF_SYNC                 0x01            /* Waker goes to sleep after wakeup */
1645#define WF_FORK                 0x02            /* Child wakeup after fork */
1646#define WF_MIGRATED             0x4             /* Internal use, task got migrated */
1647
1648/*
1649 * To aid in avoiding the subversion of "niceness" due to uneven distribution
1650 * of tasks with abnormal "nice" values across CPUs the contribution that
1651 * each task makes to its run queue's load is weighted according to its
1652 * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
1653 * scaled version of the new time slice allocation that they receive on time
1654 * slice expiry etc.
1655 */
1656
1657#define WEIGHT_IDLEPRIO         3
1658#define WMULT_IDLEPRIO          1431655765
1659
1660extern const int                sched_prio_to_weight[40];
1661extern const u32                sched_prio_to_wmult[40];
1662
1663/*
1664 * {de,en}queue flags:
1665 *
1666 * DEQUEUE_SLEEP  - task is no longer runnable
1667 * ENQUEUE_WAKEUP - task just became runnable
1668 *
1669 * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
1670 *                are in a known state which allows modification. Such pairs
1671 *                should preserve as much state as possible.
1672 *
1673 * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
1674 *        in the runqueue.
1675 *
1676 * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
1677 * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
1678 * ENQUEUE_MIGRATED  - the task was migrated during wakeup
1679 *
1680 */
1681
1682#define DEQUEUE_SLEEP           0x01
1683#define DEQUEUE_SAVE            0x02 /* Matches ENQUEUE_RESTORE */
1684#define DEQUEUE_MOVE            0x04 /* Matches ENQUEUE_MOVE */
1685#define DEQUEUE_NOCLOCK         0x08 /* Matches ENQUEUE_NOCLOCK */
1686
1687#define ENQUEUE_WAKEUP          0x01
1688#define ENQUEUE_RESTORE         0x02
1689#define ENQUEUE_MOVE            0x04
1690#define ENQUEUE_NOCLOCK         0x08
1691
1692#define ENQUEUE_HEAD            0x10
1693#define ENQUEUE_REPLENISH       0x20
1694#ifdef CONFIG_SMP
1695#define ENQUEUE_MIGRATED        0x40
1696#else
1697#define ENQUEUE_MIGRATED        0x00
1698#endif
1699
1700#define RETRY_TASK              ((void *)-1UL)
1701
1702struct sched_class {
1703        const struct sched_class *next;
1704
1705#ifdef CONFIG_UCLAMP_TASK
1706        int uclamp_enabled;
1707#endif
1708
1709        void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1710        void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1711        void (*yield_task)   (struct rq *rq);
1712        bool (*yield_to_task)(struct rq *rq, struct task_struct *p, bool preempt);
1713
1714        void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags);
1715
1716        /*
1717         * Both @prev and @rf are optional and may be NULL, in which case the
1718         * caller must already have invoked put_prev_task(rq, prev, rf).
1719         *
1720         * Otherwise it is the responsibility of the pick_next_task() to call
1721         * put_prev_task() on the @prev task or something equivalent, IFF it
1722         * returns a next task.
1723         *
1724         * In that case (@rf != NULL) it may return RETRY_TASK when it finds a
1725         * higher prio class has runnable tasks.
1726         */
1727        struct task_struct * (*pick_next_task)(struct rq *rq,
1728                                               struct task_struct *prev,
1729                                               struct rq_flags *rf);
1730        void (*put_prev_task)(struct rq *rq, struct task_struct *p);
1731        void (*set_next_task)(struct rq *rq, struct task_struct *p);
1732
1733#ifdef CONFIG_SMP
1734        int (*balance)(struct rq *rq, struct task_struct *prev, struct rq_flags *rf);
1735        int  (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
1736        void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
1737
1738        void (*task_woken)(struct rq *this_rq, struct task_struct *task);
1739
1740        void (*set_cpus_allowed)(struct task_struct *p,
1741                                 const struct cpumask *newmask);
1742
1743        void (*rq_online)(struct rq *rq);
1744        void (*rq_offline)(struct rq *rq);
1745#endif
1746
1747        void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
1748        void (*task_fork)(struct task_struct *p);
1749        void (*task_dead)(struct task_struct *p);
1750
1751        /*
1752         * The switched_from() call is allowed to drop rq->lock, therefore we
1753         * cannot assume the switched_from/switched_to pair is serliazed by
1754         * rq->lock. They are however serialized by p->pi_lock.
1755         */
1756        void (*switched_from)(struct rq *this_rq, struct task_struct *task);
1757        void (*switched_to)  (struct rq *this_rq, struct task_struct *task);
1758        void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1759                              int oldprio);
1760
1761        unsigned int (*get_rr_interval)(struct rq *rq,
1762                                        struct task_struct *task);
1763
1764        void (*update_curr)(struct rq *rq);
1765
1766#define TASK_SET_GROUP          0
1767#define TASK_MOVE_GROUP         1
1768
1769#ifdef CONFIG_FAIR_GROUP_SCHED
1770        void (*task_change_group)(struct task_struct *p, int type);
1771#endif
1772};
1773
1774static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
1775{
1776        WARN_ON_ONCE(rq->curr != prev);
1777        prev->sched_class->put_prev_task(rq, prev);
1778}
1779
1780static inline void set_next_task(struct rq *rq, struct task_struct *next)
1781{
1782        WARN_ON_ONCE(rq->curr != next);
1783        next->sched_class->set_next_task(rq, next);
1784}
1785
1786#ifdef CONFIG_SMP
1787#define sched_class_highest (&stop_sched_class)
1788#else
1789#define sched_class_highest (&dl_sched_class)
1790#endif
1791
1792#define for_class_range(class, _from, _to) \
1793        for (class = (_from); class != (_to); class = class->next)
1794
1795#define for_each_class(class) \
1796        for_class_range(class, sched_class_highest, NULL)
1797
1798extern const struct sched_class stop_sched_class;
1799extern const struct sched_class dl_sched_class;
1800extern const struct sched_class rt_sched_class;
1801extern const struct sched_class fair_sched_class;
1802extern const struct sched_class idle_sched_class;
1803
1804static inline bool sched_stop_runnable(struct rq *rq)
1805{
1806        return rq->stop && task_on_rq_queued(rq->stop);
1807}
1808
1809static inline bool sched_dl_runnable(struct rq *rq)
1810{
1811        return rq->dl.dl_nr_running > 0;
1812}
1813
1814static inline bool sched_rt_runnable(struct rq *rq)
1815{
1816        return rq->rt.rt_queued > 0;
1817}
1818
1819static inline bool sched_fair_runnable(struct rq *rq)
1820{
1821        return rq->cfs.nr_running > 0;
1822}
1823
1824#ifdef CONFIG_SMP
1825
1826extern void update_group_capacity(struct sched_domain *sd, int cpu);
1827
1828extern void trigger_load_balance(struct rq *rq);
1829
1830extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask);
1831
1832#endif
1833
1834#ifdef CONFIG_CPU_IDLE
1835static inline void idle_set_state(struct rq *rq,
1836                                  struct cpuidle_state *idle_state)
1837{
1838        rq->idle_state = idle_state;
1839}
1840
1841static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1842{
1843        SCHED_WARN_ON(!rcu_read_lock_held());
1844
1845        return rq->idle_state;
1846}
1847#else
1848static inline void idle_set_state(struct rq *rq,
1849                                  struct cpuidle_state *idle_state)
1850{
1851}
1852
1853static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1854{
1855        return NULL;
1856}
1857#endif
1858
1859extern void schedule_idle(void);
1860
1861extern void sysrq_sched_debug_show(void);
1862extern void sched_init_granularity(void);
1863extern void update_max_interval(void);
1864
1865extern void init_sched_dl_class(void);
1866extern void init_sched_rt_class(void);
1867extern void init_sched_fair_class(void);
1868
1869extern void reweight_task(struct task_struct *p, int prio);
1870
1871extern void resched_curr(struct rq *rq);
1872extern void resched_cpu(int cpu);
1873
1874extern struct rt_bandwidth def_rt_bandwidth;
1875extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
1876
1877extern struct dl_bandwidth def_dl_bandwidth;
1878extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
1879extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
1880extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
1881extern void init_dl_rq_bw_ratio(struct dl_rq *dl_rq);
1882
1883#define BW_SHIFT                20
1884#define BW_UNIT                 (1 << BW_SHIFT)
1885#define RATIO_SHIFT             8
1886unsigned long to_ratio(u64 period, u64 runtime);
1887
1888extern void init_entity_runnable_average(struct sched_entity *se);
1889extern void post_init_entity_util_avg(struct task_struct *p);
1890
1891#ifdef CONFIG_NO_HZ_FULL
1892extern bool sched_can_stop_tick(struct rq *rq);
1893extern int __init sched_tick_offload_init(void);
1894
1895/*
1896 * Tick may be needed by tasks in the runqueue depending on their policy and
1897 * requirements. If tick is needed, lets send the target an IPI to kick it out of
1898 * nohz mode if necessary.
1899 */
1900static inline void sched_update_tick_dependency(struct rq *rq)
1901{
1902        int cpu;
1903
1904        if (!tick_nohz_full_enabled())
1905                return;
1906
1907        cpu = cpu_of(rq);
1908
1909        if (!tick_nohz_full_cpu(cpu))
1910                return;
1911
1912        if (sched_can_stop_tick(rq))
1913                tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
1914        else
1915                tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
1916}
1917#else
1918static inline int sched_tick_offload_init(void) { return 0; }
1919static inline void sched_update_tick_dependency(struct rq *rq) { }
1920#endif
1921
1922static inline void add_nr_running(struct rq *rq, unsigned count)
1923{
1924        unsigned prev_nr = rq->nr_running;
1925
1926        rq->nr_running = prev_nr + count;
1927
1928#ifdef CONFIG_SMP
1929        if (prev_nr < 2 && rq->nr_running >= 2) {
1930                if (!READ_ONCE(rq->rd->overload))
1931                        WRITE_ONCE(rq->rd->overload, 1);
1932        }
1933#endif
1934
1935        sched_update_tick_dependency(rq);
1936}
1937
1938static inline void sub_nr_running(struct rq *rq, unsigned count)
1939{
1940        rq->nr_running -= count;
1941        /* Check if we still need preemption */
1942        sched_update_tick_dependency(rq);
1943}
1944
1945extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
1946extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
1947
1948extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
1949
1950extern const_debug unsigned int sysctl_sched_nr_migrate;
1951extern const_debug unsigned int sysctl_sched_migration_cost;
1952
1953#ifdef CONFIG_SCHED_HRTICK
1954
1955/*
1956 * Use hrtick when:
1957 *  - enabled by features
1958 *  - hrtimer is actually high res
1959 */
1960static inline int hrtick_enabled(struct rq *rq)
1961{
1962        if (!sched_feat(HRTICK))
1963                return 0;
1964        if (!cpu_active(cpu_of(rq)))
1965                return 0;
1966        return hrtimer_is_hres_active(&rq->hrtick_timer);
1967}
1968
1969void hrtick_start(struct rq *rq, u64 delay);
1970
1971#else
1972
1973static inline int hrtick_enabled(struct rq *rq)
1974{
1975        return 0;
1976}
1977
1978#endif /* CONFIG_SCHED_HRTICK */
1979
1980#ifndef arch_scale_freq_capacity
1981static __always_inline
1982unsigned long arch_scale_freq_capacity(int cpu)
1983{
1984        return SCHED_CAPACITY_SCALE;
1985}
1986#endif
1987
1988#ifdef CONFIG_SMP
1989#ifdef CONFIG_PREEMPTION
1990
1991static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
1992
1993/*
1994 * fair double_lock_balance: Safely acquires both rq->locks in a fair
1995 * way at the expense of forcing extra atomic operations in all
1996 * invocations.  This assures that the double_lock is acquired using the
1997 * same underlying policy as the spinlock_t on this architecture, which
1998 * reduces latency compared to the unfair variant below.  However, it
1999 * also adds more overhead and therefore may reduce throughput.
2000 */
2001static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2002        __releases(this_rq->lock)
2003        __acquires(busiest->lock)
2004        __acquires(this_rq->lock)
2005{
2006        raw_spin_unlock(&this_rq->lock);
2007        double_rq_lock(this_rq, busiest);
2008
2009        return 1;
2010}
2011
2012#else
2013/*
2014 * Unfair double_lock_balance: Optimizes throughput at the expense of
2015 * latency by eliminating extra atomic operations when the locks are
2016 * already in proper order on entry.  This favors lower CPU-ids and will
2017 * grant the double lock to lower CPUs over higher ids under contention,
2018 * regardless of entry order into the function.
2019 */
2020static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
2021        __releases(this_rq->lock)
2022        __acquires(busiest->lock)
2023        __acquires(this_rq->lock)
2024{
2025        int ret = 0;
2026
2027        if (unlikely(!raw_spin_trylock(&busiest->lock))) {
2028                if (busiest < this_rq) {
2029                        raw_spin_unlock(&this_rq->lock);
2030                        raw_spin_lock(&busiest->lock);
2031                        raw_spin_lock_nested(&this_rq->lock,
2032                                              SINGLE_DEPTH_NESTING);
2033                        ret = 1;
2034                } else
2035                        raw_spin_lock_nested(&busiest->lock,
2036                                              SINGLE_DEPTH_NESTING);
2037        }
2038        return ret;
2039}
2040
2041#endif /* CONFIG_PREEMPTION */
2042
2043/*
2044 * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
2045 */
2046static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
2047{
2048        if (unlikely(!irqs_disabled())) {
2049                /* printk() doesn't work well under rq->lock */
2050                raw_spin_unlock(&this_rq->lock);
2051                BUG_ON(1);
2052        }
2053
2054        return _double_lock_balance(this_rq, busiest);
2055}
2056
2057static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
2058        __releases(busiest->lock)
2059{
2060        raw_spin_unlock(&busiest->lock);
2061        lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
2062}
2063
2064static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
2065{
2066        if (l1 > l2)
2067                swap(l1, l2);
2068
2069        spin_lock(l1);
2070        spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2071}
2072
2073static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
2074{
2075        if (l1 > l2)
2076                swap(l1, l2);
2077
2078        spin_lock_irq(l1);
2079        spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2080}
2081
2082static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
2083{
2084        if (l1 > l2)
2085                swap(l1, l2);
2086
2087        raw_spin_lock(l1);
2088        raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
2089}
2090
2091/*
2092 * double_rq_lock - safely lock two runqueues
2093 *
2094 * Note this does not disable interrupts like task_rq_lock,
2095 * you need to do so manually before calling.
2096 */
2097static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2098        __acquires(rq1->lock)
2099        __acquires(rq2->lock)
2100{
2101        BUG_ON(!irqs_disabled());
2102        if (rq1 == rq2) {
2103                raw_spin_lock(&rq1->lock);
2104                __acquire(rq2->lock);   /* Fake it out ;) */
2105        } else {
2106                if (rq1 < rq2) {
2107                        raw_spin_lock(&rq1->lock);
2108                        raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
2109                } else {
2110                        raw_spin_lock(&rq2->lock);
2111                        raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
2112                }
2113        }
2114}
2115
2116/*
2117 * double_rq_unlock - safely unlock two runqueues
2118 *
2119 * Note this does not restore interrupts like task_rq_unlock,
2120 * you need to do so manually after calling.
2121 */
2122static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2123        __releases(rq1->lock)
2124        __releases(rq2->lock)
2125{
2126        raw_spin_unlock(&rq1->lock);
2127        if (rq1 != rq2)
2128                raw_spin_unlock(&rq2->lock);
2129        else
2130                __release(rq2->lock);
2131}
2132
2133extern void set_rq_online (struct rq *rq);
2134extern void set_rq_offline(struct rq *rq);
2135extern bool sched_smp_initialized;
2136
2137#else /* CONFIG_SMP */
2138
2139/*
2140 * double_rq_lock - safely lock two runqueues
2141 *
2142 * Note this does not disable interrupts like task_rq_lock,
2143 * you need to do so manually before calling.
2144 */
2145static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2146        __acquires(rq1->lock)
2147        __acquires(rq2->lock)
2148{
2149        BUG_ON(!irqs_disabled());
2150        BUG_ON(rq1 != rq2);
2151        raw_spin_lock(&rq1->lock);
2152        __acquire(rq2->lock);   /* Fake it out ;) */
2153}
2154
2155/*
2156 * double_rq_unlock - safely unlock two runqueues
2157 *
2158 * Note this does not restore interrupts like task_rq_unlock,
2159 * you need to do so manually after calling.
2160 */
2161static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2162        __releases(rq1->lock)
2163        __releases(rq2->lock)
2164{
2165        BUG_ON(rq1 != rq2);
2166        raw_spin_unlock(&rq1->lock);
2167        __release(rq2->lock);
2168}
2169
2170#endif
2171
2172extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
2173extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
2174
2175#ifdef  CONFIG_SCHED_DEBUG
2176extern bool sched_debug_enabled;
2177
2178extern void print_cfs_stats(struct seq_file *m, int cpu);
2179extern void print_rt_stats(struct seq_file *m, int cpu);
2180extern void print_dl_stats(struct seq_file *m, int cpu);
2181extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
2182extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2183extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
2184#ifdef CONFIG_NUMA_BALANCING
2185extern void
2186show_numa_stats(struct task_struct *p, struct seq_file *m);
2187extern void
2188print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
2189        unsigned long tpf, unsigned long gsf, unsigned long gpf);
2190#endif /* CONFIG_NUMA_BALANCING */
2191#endif /* CONFIG_SCHED_DEBUG */
2192
2193extern void init_cfs_rq(struct cfs_rq *cfs_rq);
2194extern void init_rt_rq(struct rt_rq *rt_rq);
2195extern void init_dl_rq(struct dl_rq *dl_rq);
2196
2197extern void cfs_bandwidth_usage_inc(void);
2198extern void cfs_bandwidth_usage_dec(void);
2199
2200#ifdef CONFIG_NO_HZ_COMMON
2201#define NOHZ_BALANCE_KICK_BIT   0
2202#define NOHZ_STATS_KICK_BIT     1
2203
2204#define NOHZ_BALANCE_KICK       BIT(NOHZ_BALANCE_KICK_BIT)
2205#define NOHZ_STATS_KICK         BIT(NOHZ_STATS_KICK_BIT)
2206
2207#define NOHZ_KICK_MASK  (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK)
2208
2209#define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
2210
2211extern void nohz_balance_exit_idle(struct rq *rq);
2212#else
2213static inline void nohz_balance_exit_idle(struct rq *rq) { }
2214#endif
2215
2216
2217#ifdef CONFIG_SMP
2218static inline
2219void __dl_update(struct dl_bw *dl_b, s64 bw)
2220{
2221        struct root_domain *rd = container_of(dl_b, struct root_domain, dl_bw);
2222        int i;
2223
2224        RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
2225                         "sched RCU must be held");
2226        for_each_cpu_and(i, rd->span, cpu_active_mask) {
2227                struct rq *rq = cpu_rq(i);
2228
2229                rq->dl.extra_bw += bw;
2230        }
2231}
2232#else
2233static inline
2234void __dl_update(struct dl_bw *dl_b, s64 bw)
2235{
2236        struct dl_rq *dl = container_of(dl_b, struct dl_rq, dl_bw);
2237
2238        dl->extra_bw += bw;
2239}
2240#endif
2241
2242
2243#ifdef CONFIG_IRQ_TIME_ACCOUNTING
2244struct irqtime {
2245        u64                     total;
2246        u64                     tick_delta;
2247        u64                     irq_start_time;
2248        struct u64_stats_sync   sync;
2249};
2250
2251DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2252
2253/*
2254 * Returns the irqtime minus the softirq time computed by ksoftirqd.
2255 * Otherwise ksoftirqd's sum_exec_runtime is substracted its own runtime
2256 * and never move forward.
2257 */
2258static inline u64 irq_time_read(int cpu)
2259{
2260        struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2261        unsigned int seq;
2262        u64 total;
2263
2264        do {
2265                seq = __u64_stats_fetch_begin(&irqtime->sync);
2266                total = irqtime->total;
2267        } while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2268
2269        return total;
2270}
2271#endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2272
2273#ifdef CONFIG_CPU_FREQ
2274DECLARE_PER_CPU(struct update_util_data __rcu *, cpufreq_update_util_data);
2275
2276/**
2277 * cpufreq_update_util - Take a note about CPU utilization changes.
2278 * @rq: Runqueue to carry out the update for.
2279 * @flags: Update reason flags.
2280 *
2281 * This function is called by the scheduler on the CPU whose utilization is
2282 * being updated.
2283 *
2284 * It can only be called from RCU-sched read-side critical sections.
2285 *
2286 * The way cpufreq is currently arranged requires it to evaluate the CPU
2287 * performance state (frequency/voltage) on a regular basis to prevent it from
2288 * being stuck in a completely inadequate performance level for too long.
2289 * That is not guaranteed to happen if the updates are only triggered from CFS
2290 * and DL, though, because they may not be coming in if only RT tasks are
2291 * active all the time (or there are RT tasks only).
2292 *
2293 * As a workaround for that issue, this function is called periodically by the
2294 * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
2295 * but that really is a band-aid.  Going forward it should be replaced with
2296 * solutions targeted more specifically at RT tasks.
2297 */
2298static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2299{
2300        struct update_util_data *data;
2301
2302        data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2303                                                  cpu_of(rq)));
2304        if (data)
2305                data->func(data, rq_clock(rq), flags);
2306}
2307#else
2308static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2309#endif /* CONFIG_CPU_FREQ */
2310
2311#ifdef CONFIG_UCLAMP_TASK
2312enum uclamp_id uclamp_eff_value(struct task_struct *p, enum uclamp_id clamp_id);
2313
2314static __always_inline
2315unsigned int uclamp_util_with(struct rq *rq, unsigned int util,
2316                              struct task_struct *p)
2317{
2318        unsigned int min_util = READ_ONCE(rq->uclamp[UCLAMP_MIN].value);
2319        unsigned int max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value);
2320
2321        if (p) {
2322                min_util = max(min_util, uclamp_eff_value(p, UCLAMP_MIN));
2323                max_util = max(max_util, uclamp_eff_value(p, UCLAMP_MAX));
2324        }
2325
2326        /*
2327         * Since CPU's {min,max}_util clamps are MAX aggregated considering
2328         * RUNNABLE tasks with _different_ clamps, we can end up with an
2329         * inversion. Fix it now when the clamps are applied.
2330         */
2331        if (unlikely(min_util >= max_util))
2332                return min_util;
2333
2334        return clamp(util, min_util, max_util);
2335}
2336
2337static inline unsigned int uclamp_util(struct rq *rq, unsigned int util)
2338{
2339        return uclamp_util_with(rq, util, NULL);
2340}
2341#else /* CONFIG_UCLAMP_TASK */
2342static inline unsigned int uclamp_util_with(struct rq *rq, unsigned int util,
2343                                            struct task_struct *p)
2344{
2345        return util;
2346}
2347static inline unsigned int uclamp_util(struct rq *rq, unsigned int util)
2348{
2349        return util;
2350}
2351#endif /* CONFIG_UCLAMP_TASK */
2352
2353#ifdef arch_scale_freq_capacity
2354# ifndef arch_scale_freq_invariant
2355#  define arch_scale_freq_invariant()   true
2356# endif
2357#else
2358# define arch_scale_freq_invariant()    false
2359#endif
2360
2361#ifdef CONFIG_SMP
2362static inline unsigned long capacity_orig_of(int cpu)
2363{
2364        return cpu_rq(cpu)->cpu_capacity_orig;
2365}
2366#endif
2367
2368/**
2369 * enum schedutil_type - CPU utilization type
2370 * @FREQUENCY_UTIL:     Utilization used to select frequency
2371 * @ENERGY_UTIL:        Utilization used during energy calculation
2372 *
2373 * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time
2374 * need to be aggregated differently depending on the usage made of them. This
2375 * enum is used within schedutil_freq_util() to differentiate the types of
2376 * utilization expected by the callers, and adjust the aggregation accordingly.
2377 */
2378enum schedutil_type {
2379        FREQUENCY_UTIL,
2380        ENERGY_UTIL,
2381};
2382
2383#ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
2384
2385unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
2386                                 unsigned long max, enum schedutil_type type,
2387                                 struct task_struct *p);
2388
2389static inline unsigned long cpu_bw_dl(struct rq *rq)
2390{
2391        return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
2392}
2393
2394static inline unsigned long cpu_util_dl(struct rq *rq)
2395{
2396        return READ_ONCE(rq->avg_dl.util_avg);
2397}
2398
2399static inline unsigned long cpu_util_cfs(struct rq *rq)
2400{
2401        unsigned long util = READ_ONCE(rq->cfs.avg.util_avg);
2402
2403        if (sched_feat(UTIL_EST)) {
2404                util = max_t(unsigned long, util,
2405                             READ_ONCE(rq->cfs.avg.util_est.enqueued));
2406        }
2407
2408        return util;
2409}
2410
2411static inline unsigned long cpu_util_rt(struct rq *rq)
2412{
2413        return READ_ONCE(rq->avg_rt.util_avg);
2414}
2415#else /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
2416static inline unsigned long schedutil_cpu_util(int cpu, unsigned long util_cfs,
2417                                 unsigned long max, enum schedutil_type type,
2418                                 struct task_struct *p)
2419{
2420        return 0;
2421}
2422#endif /* CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
2423
2424#ifdef CONFIG_HAVE_SCHED_AVG_IRQ
2425static inline unsigned long cpu_util_irq(struct rq *rq)
2426{
2427        return rq->avg_irq.util_avg;
2428}
2429
2430static inline
2431unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2432{
2433        util *= (max - irq);
2434        util /= max;
2435
2436        return util;
2437
2438}
2439#else
2440static inline unsigned long cpu_util_irq(struct rq *rq)
2441{
2442        return 0;
2443}
2444
2445static inline
2446unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2447{
2448        return util;
2449}
2450#endif
2451
2452#if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
2453
2454#define perf_domain_span(pd) (to_cpumask(((pd)->em_pd->cpus)))
2455
2456DECLARE_STATIC_KEY_FALSE(sched_energy_present);
2457
2458static inline bool sched_energy_enabled(void)
2459{
2460        return static_branch_unlikely(&sched_energy_present);
2461}
2462
2463#else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */
2464
2465#define perf_domain_span(pd) NULL
2466static inline bool sched_energy_enabled(void) { return false; }
2467
2468#endif /* CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL */
2469
2470#ifdef CONFIG_MEMBARRIER
2471/*
2472 * The scheduler provides memory barriers required by membarrier between:
2473 * - prior user-space memory accesses and store to rq->membarrier_state,
2474 * - store to rq->membarrier_state and following user-space memory accesses.
2475 * In the same way it provides those guarantees around store to rq->curr.
2476 */
2477static inline void membarrier_switch_mm(struct rq *rq,
2478                                        struct mm_struct *prev_mm,
2479                                        struct mm_struct *next_mm)
2480{
2481        int membarrier_state;
2482
2483        if (prev_mm == next_mm)
2484                return;
2485
2486        membarrier_state = atomic_read(&next_mm->membarrier_state);
2487        if (READ_ONCE(rq->membarrier_state) == membarrier_state)
2488                return;
2489
2490        WRITE_ONCE(rq->membarrier_state, membarrier_state);
2491}
2492#else
2493static inline void membarrier_switch_mm(struct rq *rq,
2494                                        struct mm_struct *prev_mm,
2495                                        struct mm_struct *next_mm)
2496{
2497}
2498#endif
2499