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