1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_SCHED_H 3 #define _LINUX_SCHED_H 4 5 /* 6 * Define 'struct task_struct' and provide the main scheduler 7 * APIs (schedule(), wakeup variants, etc.) 8 */ 9 10 #include <uapi/linux/sched.h> 11 12 #include <asm/current.h> 13 #include <asm/processor.h> 14 #include <linux/thread_info.h> 15 #include <linux/preempt.h> 16 #include <linux/cpumask_types.h> 17 18 #include <linux/cache.h> 19 #include <linux/irqflags_types.h> 20 #include <linux/smp_types.h> 21 #include <linux/pid_types.h> 22 #include <linux/sem_types.h> 23 #include <linux/shm.h> 24 #include <linux/kmsan_types.h> 25 #include <linux/mutex_types.h> 26 #include <linux/plist_types.h> 27 #include <linux/hrtimer_types.h> 28 #include <linux/timer_types.h> 29 #include <linux/seccomp_types.h> 30 #include <linux/nodemask_types.h> 31 #include <linux/refcount_types.h> 32 #include <linux/resource.h> 33 #include <linux/latencytop.h> 34 #include <linux/sched/prio.h> 35 #include <linux/sched/types.h> 36 #include <linux/signal_types.h> 37 #include <linux/spinlock.h> 38 #include <linux/syscall_user_dispatch_types.h> 39 #include <linux/mm_types_task.h> 40 #include <linux/netdevice_xmit.h> 41 #include <linux/task_io_accounting.h> 42 #include <linux/posix-timers_types.h> 43 #include <linux/restart_block.h> 44 #include <uapi/linux/rseq.h> 45 #include <linux/seqlock_types.h> 46 #include <linux/kcsan.h> 47 #include <linux/rv.h> 48 #include <linux/uidgid_types.h> 49 #include <linux/tracepoint-defs.h> 50 #include <asm/kmap_size.h> 51 52 /* task_struct member predeclarations (sorted alphabetically): */ 53 struct audit_context; 54 struct bio_list; 55 struct blk_plug; 56 struct bpf_local_storage; 57 struct bpf_run_ctx; 58 struct bpf_net_context; 59 struct capture_control; 60 struct cfs_rq; 61 struct fs_struct; 62 struct futex_pi_state; 63 struct io_context; 64 struct io_uring_task; 65 struct mempolicy; 66 struct nameidata; 67 struct nsproxy; 68 struct perf_event_context; 69 struct perf_ctx_data; 70 struct pid_namespace; 71 struct pipe_inode_info; 72 struct rcu_node; 73 struct reclaim_state; 74 struct robust_list_head; 75 struct root_domain; 76 struct rq; 77 struct sched_attr; 78 struct sched_dl_entity; 79 struct seq_file; 80 struct sighand_struct; 81 struct signal_struct; 82 struct task_delay_info; 83 struct task_group; 84 struct task_struct; 85 struct user_event_mm; 86 87 #include <linux/sched/ext.h> 88 89 /* 90 * Task state bitmask. NOTE! These bits are also 91 * encoded in fs/proc/array.c: get_task_state(). 92 * 93 * We have two separate sets of flags: task->__state 94 * is about runnability, while task->exit_state are 95 * about the task exiting. Confusing, but this way 96 * modifying one set can't modify the other one by 97 * mistake. 98 */ 99 100 /* Used in tsk->__state: */ 101 #define TASK_RUNNING 0x00000000 102 #define TASK_INTERRUPTIBLE 0x00000001 103 #define TASK_UNINTERRUPTIBLE 0x00000002 104 #define __TASK_STOPPED 0x00000004 105 #define __TASK_TRACED 0x00000008 106 /* Used in tsk->exit_state: */ 107 #define EXIT_DEAD 0x00000010 108 #define EXIT_ZOMBIE 0x00000020 109 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD) 110 /* Used in tsk->__state again: */ 111 #define TASK_PARKED 0x00000040 112 #define TASK_DEAD 0x00000080 113 #define TASK_WAKEKILL 0x00000100 114 #define TASK_WAKING 0x00000200 115 #define TASK_NOLOAD 0x00000400 116 #define TASK_NEW 0x00000800 117 #define TASK_RTLOCK_WAIT 0x00001000 118 #define TASK_FREEZABLE 0x00002000 119 #define __TASK_FREEZABLE_UNSAFE (0x00004000 * IS_ENABLED(CONFIG_LOCKDEP)) 120 #define TASK_FROZEN 0x00008000 121 #define TASK_STATE_MAX 0x00010000 122 123 #define TASK_ANY (TASK_STATE_MAX-1) 124 125 /* 126 * DO NOT ADD ANY NEW USERS ! 127 */ 128 #define TASK_FREEZABLE_UNSAFE (TASK_FREEZABLE | __TASK_FREEZABLE_UNSAFE) 129 130 /* Convenience macros for the sake of set_current_state: */ 131 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 132 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 133 #define TASK_TRACED __TASK_TRACED 134 135 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD) 136 137 /* Convenience macros for the sake of wake_up(): */ 138 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 139 140 /* get_task_state(): */ 141 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 142 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 143 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \ 144 TASK_PARKED) 145 146 #define task_is_running(task) (READ_ONCE((task)->__state) == TASK_RUNNING) 147 148 #define task_is_traced(task) ((READ_ONCE(task->jobctl) & JOBCTL_TRACED) != 0) 149 #define task_is_stopped(task) ((READ_ONCE(task->jobctl) & JOBCTL_STOPPED) != 0) 150 #define task_is_stopped_or_traced(task) ((READ_ONCE(task->jobctl) & (JOBCTL_STOPPED | JOBCTL_TRACED)) != 0) 151 152 /* 153 * Special states are those that do not use the normal wait-loop pattern. See 154 * the comment with set_special_state(). 155 */ 156 #define is_special_task_state(state) \ 157 ((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | \ 158 TASK_DEAD | TASK_FROZEN)) 159 160 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 161 # define debug_normal_state_change(state_value) \ 162 do { \ 163 WARN_ON_ONCE(is_special_task_state(state_value)); \ 164 current->task_state_change = _THIS_IP_; \ 165 } while (0) 166 167 # define debug_special_state_change(state_value) \ 168 do { \ 169 WARN_ON_ONCE(!is_special_task_state(state_value)); \ 170 current->task_state_change = _THIS_IP_; \ 171 } while (0) 172 173 # define debug_rtlock_wait_set_state() \ 174 do { \ 175 current->saved_state_change = current->task_state_change;\ 176 current->task_state_change = _THIS_IP_; \ 177 } while (0) 178 179 # define debug_rtlock_wait_restore_state() \ 180 do { \ 181 current->task_state_change = current->saved_state_change;\ 182 } while (0) 183 184 #else 185 # define debug_normal_state_change(cond) do { } while (0) 186 # define debug_special_state_change(cond) do { } while (0) 187 # define debug_rtlock_wait_set_state() do { } while (0) 188 # define debug_rtlock_wait_restore_state() do { } while (0) 189 #endif 190 191 #define trace_set_current_state(state_value) \ 192 do { \ 193 if (tracepoint_enabled(sched_set_state_tp)) \ 194 __trace_set_current_state(state_value); \ 195 } while (0) 196 197 /* 198 * set_current_state() includes a barrier so that the write of current->__state 199 * is correctly serialised wrt the caller's subsequent test of whether to 200 * actually sleep: 201 * 202 * for (;;) { 203 * set_current_state(TASK_UNINTERRUPTIBLE); 204 * if (CONDITION) 205 * break; 206 * 207 * schedule(); 208 * } 209 * __set_current_state(TASK_RUNNING); 210 * 211 * If the caller does not need such serialisation (because, for instance, the 212 * CONDITION test and condition change and wakeup are under the same lock) then 213 * use __set_current_state(). 214 * 215 * The above is typically ordered against the wakeup, which does: 216 * 217 * CONDITION = 1; 218 * wake_up_state(p, TASK_UNINTERRUPTIBLE); 219 * 220 * where wake_up_state()/try_to_wake_up() executes a full memory barrier before 221 * accessing p->__state. 222 * 223 * Wakeup will do: if (@state & p->__state) p->__state = TASK_RUNNING, that is, 224 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a 225 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING). 226 * 227 * However, with slightly different timing the wakeup TASK_RUNNING store can 228 * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not 229 * a problem either because that will result in one extra go around the loop 230 * and our @cond test will save the day. 231 * 232 * Also see the comments of try_to_wake_up(). 233 */ 234 #define __set_current_state(state_value) \ 235 do { \ 236 debug_normal_state_change((state_value)); \ 237 trace_set_current_state(state_value); \ 238 WRITE_ONCE(current->__state, (state_value)); \ 239 } while (0) 240 241 #define set_current_state(state_value) \ 242 do { \ 243 debug_normal_state_change((state_value)); \ 244 trace_set_current_state(state_value); \ 245 smp_store_mb(current->__state, (state_value)); \ 246 } while (0) 247 248 /* 249 * set_special_state() should be used for those states when the blocking task 250 * can not use the regular condition based wait-loop. In that case we must 251 * serialize against wakeups such that any possible in-flight TASK_RUNNING 252 * stores will not collide with our state change. 253 */ 254 #define set_special_state(state_value) \ 255 do { \ 256 unsigned long flags; /* may shadow */ \ 257 \ 258 raw_spin_lock_irqsave(¤t->pi_lock, flags); \ 259 debug_special_state_change((state_value)); \ 260 trace_set_current_state(state_value); \ 261 WRITE_ONCE(current->__state, (state_value)); \ 262 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \ 263 } while (0) 264 265 /* 266 * PREEMPT_RT specific variants for "sleeping" spin/rwlocks 267 * 268 * RT's spin/rwlock substitutions are state preserving. The state of the 269 * task when blocking on the lock is saved in task_struct::saved_state and 270 * restored after the lock has been acquired. These operations are 271 * serialized by task_struct::pi_lock against try_to_wake_up(). Any non RT 272 * lock related wakeups while the task is blocked on the lock are 273 * redirected to operate on task_struct::saved_state to ensure that these 274 * are not dropped. On restore task_struct::saved_state is set to 275 * TASK_RUNNING so any wakeup attempt redirected to saved_state will fail. 276 * 277 * The lock operation looks like this: 278 * 279 * current_save_and_set_rtlock_wait_state(); 280 * for (;;) { 281 * if (try_lock()) 282 * break; 283 * raw_spin_unlock_irq(&lock->wait_lock); 284 * schedule_rtlock(); 285 * raw_spin_lock_irq(&lock->wait_lock); 286 * set_current_state(TASK_RTLOCK_WAIT); 287 * } 288 * current_restore_rtlock_saved_state(); 289 */ 290 #define current_save_and_set_rtlock_wait_state() \ 291 do { \ 292 lockdep_assert_irqs_disabled(); \ 293 raw_spin_lock(¤t->pi_lock); \ 294 current->saved_state = current->__state; \ 295 debug_rtlock_wait_set_state(); \ 296 trace_set_current_state(TASK_RTLOCK_WAIT); \ 297 WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT); \ 298 raw_spin_unlock(¤t->pi_lock); \ 299 } while (0); 300 301 #define current_restore_rtlock_saved_state() \ 302 do { \ 303 lockdep_assert_irqs_disabled(); \ 304 raw_spin_lock(¤t->pi_lock); \ 305 debug_rtlock_wait_restore_state(); \ 306 trace_set_current_state(current->saved_state); \ 307 WRITE_ONCE(current->__state, current->saved_state); \ 308 current->saved_state = TASK_RUNNING; \ 309 raw_spin_unlock(¤t->pi_lock); \ 310 } while (0); 311 312 #define get_current_state() READ_ONCE(current->__state) 313 314 /* 315 * Define the task command name length as enum, then it can be visible to 316 * BPF programs. 317 */ 318 enum { 319 TASK_COMM_LEN = 16, 320 }; 321 322 extern void sched_tick(void); 323 324 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 325 326 extern long schedule_timeout(long timeout); 327 extern long schedule_timeout_interruptible(long timeout); 328 extern long schedule_timeout_killable(long timeout); 329 extern long schedule_timeout_uninterruptible(long timeout); 330 extern long schedule_timeout_idle(long timeout); 331 asmlinkage void schedule(void); 332 extern void schedule_preempt_disabled(void); 333 asmlinkage void preempt_schedule_irq(void); 334 #ifdef CONFIG_PREEMPT_RT 335 extern void schedule_rtlock(void); 336 #endif 337 338 extern int __must_check io_schedule_prepare(void); 339 extern void io_schedule_finish(int token); 340 extern long io_schedule_timeout(long timeout); 341 extern void io_schedule(void); 342 343 /* wrapper function to trace from this header file */ 344 DECLARE_TRACEPOINT(sched_set_state_tp); 345 extern void __trace_set_current_state(int state_value); 346 347 /** 348 * struct prev_cputime - snapshot of system and user cputime 349 * @utime: time spent in user mode 350 * @stime: time spent in system mode 351 * @lock: protects the above two fields 352 * 353 * Stores previous user/system time values such that we can guarantee 354 * monotonicity. 355 */ 356 struct prev_cputime { 357 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 358 u64 utime; 359 u64 stime; 360 raw_spinlock_t lock; 361 #endif 362 }; 363 364 enum vtime_state { 365 /* Task is sleeping or running in a CPU with VTIME inactive: */ 366 VTIME_INACTIVE = 0, 367 /* Task is idle */ 368 VTIME_IDLE, 369 /* Task runs in kernelspace in a CPU with VTIME active: */ 370 VTIME_SYS, 371 /* Task runs in userspace in a CPU with VTIME active: */ 372 VTIME_USER, 373 /* Task runs as guests in a CPU with VTIME active: */ 374 VTIME_GUEST, 375 }; 376 377 struct vtime { 378 seqcount_t seqcount; 379 unsigned long long starttime; 380 enum vtime_state state; 381 unsigned int cpu; 382 u64 utime; 383 u64 stime; 384 u64 gtime; 385 }; 386 387 /* 388 * Utilization clamp constraints. 389 * @UCLAMP_MIN: Minimum utilization 390 * @UCLAMP_MAX: Maximum utilization 391 * @UCLAMP_CNT: Utilization clamp constraints count 392 */ 393 enum uclamp_id { 394 UCLAMP_MIN = 0, 395 UCLAMP_MAX, 396 UCLAMP_CNT 397 }; 398 399 extern struct root_domain def_root_domain; 400 extern struct mutex sched_domains_mutex; 401 extern void sched_domains_mutex_lock(void); 402 extern void sched_domains_mutex_unlock(void); 403 404 struct sched_param { 405 int sched_priority; 406 }; 407 408 struct sched_info { 409 #ifdef CONFIG_SCHED_INFO 410 /* Cumulative counters: */ 411 412 /* # of times we have run on this CPU: */ 413 unsigned long pcount; 414 415 /* Time spent waiting on a runqueue: */ 416 unsigned long long run_delay; 417 418 /* Max time spent waiting on a runqueue: */ 419 unsigned long long max_run_delay; 420 421 /* Min time spent waiting on a runqueue: */ 422 unsigned long long min_run_delay; 423 424 /* Timestamps: */ 425 426 /* When did we last run on a CPU? */ 427 unsigned long long last_arrival; 428 429 /* When were we last queued to run? */ 430 unsigned long long last_queued; 431 432 #endif /* CONFIG_SCHED_INFO */ 433 }; 434 435 /* 436 * Integer metrics need fixed point arithmetic, e.g., sched/fair 437 * has a few: load, load_avg, util_avg, freq, and capacity. 438 * 439 * We define a basic fixed point arithmetic range, and then formalize 440 * all these metrics based on that basic range. 441 */ 442 # define SCHED_FIXEDPOINT_SHIFT 10 443 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT) 444 445 /* Increase resolution of cpu_capacity calculations */ 446 # define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT 447 # define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) 448 449 struct load_weight { 450 unsigned long weight; 451 u32 inv_weight; 452 }; 453 454 /* 455 * The load/runnable/util_avg accumulates an infinite geometric series 456 * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c). 457 * 458 * [load_avg definition] 459 * 460 * load_avg = runnable% * scale_load_down(load) 461 * 462 * [runnable_avg definition] 463 * 464 * runnable_avg = runnable% * SCHED_CAPACITY_SCALE 465 * 466 * [util_avg definition] 467 * 468 * util_avg = running% * SCHED_CAPACITY_SCALE 469 * 470 * where runnable% is the time ratio that a sched_entity is runnable and 471 * running% the time ratio that a sched_entity is running. 472 * 473 * For cfs_rq, they are the aggregated values of all runnable and blocked 474 * sched_entities. 475 * 476 * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU 477 * capacity scaling. The scaling is done through the rq_clock_pelt that is used 478 * for computing those signals (see update_rq_clock_pelt()) 479 * 480 * N.B., the above ratios (runnable% and running%) themselves are in the 481 * range of [0, 1]. To do fixed point arithmetics, we therefore scale them 482 * to as large a range as necessary. This is for example reflected by 483 * util_avg's SCHED_CAPACITY_SCALE. 484 * 485 * [Overflow issue] 486 * 487 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities 488 * with the highest load (=88761), always runnable on a single cfs_rq, 489 * and should not overflow as the number already hits PID_MAX_LIMIT. 490 * 491 * For all other cases (including 32-bit kernels), struct load_weight's 492 * weight will overflow first before we do, because: 493 * 494 * Max(load_avg) <= Max(load.weight) 495 * 496 * Then it is the load_weight's responsibility to consider overflow 497 * issues. 498 */ 499 struct sched_avg { 500 u64 last_update_time; 501 u64 load_sum; 502 u64 runnable_sum; 503 u32 util_sum; 504 u32 period_contrib; 505 unsigned long load_avg; 506 unsigned long runnable_avg; 507 unsigned long util_avg; 508 unsigned int util_est; 509 } ____cacheline_aligned; 510 511 /* 512 * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg 513 * updates. When a task is dequeued, its util_est should not be updated if its 514 * util_avg has not been updated in the meantime. 515 * This information is mapped into the MSB bit of util_est at dequeue time. 516 * Since max value of util_est for a task is 1024 (PELT util_avg for a task) 517 * it is safe to use MSB. 518 */ 519 #define UTIL_EST_WEIGHT_SHIFT 2 520 #define UTIL_AVG_UNCHANGED 0x80000000 521 522 struct sched_statistics { 523 #ifdef CONFIG_SCHEDSTATS 524 u64 wait_start; 525 u64 wait_max; 526 u64 wait_count; 527 u64 wait_sum; 528 u64 iowait_count; 529 u64 iowait_sum; 530 531 u64 sleep_start; 532 u64 sleep_max; 533 s64 sum_sleep_runtime; 534 535 u64 block_start; 536 u64 block_max; 537 s64 sum_block_runtime; 538 539 s64 exec_max; 540 u64 slice_max; 541 542 u64 nr_migrations_cold; 543 u64 nr_failed_migrations_affine; 544 u64 nr_failed_migrations_running; 545 u64 nr_failed_migrations_hot; 546 u64 nr_forced_migrations; 547 548 u64 nr_wakeups; 549 u64 nr_wakeups_sync; 550 u64 nr_wakeups_migrate; 551 u64 nr_wakeups_local; 552 u64 nr_wakeups_remote; 553 u64 nr_wakeups_affine; 554 u64 nr_wakeups_affine_attempts; 555 u64 nr_wakeups_passive; 556 u64 nr_wakeups_idle; 557 558 #ifdef CONFIG_SCHED_CORE 559 u64 core_forceidle_sum; 560 #endif 561 #endif /* CONFIG_SCHEDSTATS */ 562 } ____cacheline_aligned; 563 564 struct sched_entity { 565 /* For load-balancing: */ 566 struct load_weight load; 567 struct rb_node run_node; 568 u64 deadline; 569 u64 min_vruntime; 570 u64 min_slice; 571 572 struct list_head group_node; 573 unsigned char on_rq; 574 unsigned char sched_delayed; 575 unsigned char rel_deadline; 576 unsigned char custom_slice; 577 /* hole */ 578 579 u64 exec_start; 580 u64 sum_exec_runtime; 581 u64 prev_sum_exec_runtime; 582 u64 vruntime; 583 union { 584 /* 585 * When !@on_rq this field is vlag. 586 * When cfs_rq->curr == se (which implies @on_rq) 587 * this field is vprot. See protect_slice(). 588 */ 589 s64 vlag; 590 u64 vprot; 591 }; 592 u64 slice; 593 594 u64 nr_migrations; 595 596 #ifdef CONFIG_FAIR_GROUP_SCHED 597 int depth; 598 struct sched_entity *parent; 599 /* rq on which this entity is (to be) queued: */ 600 struct cfs_rq *cfs_rq; 601 /* rq "owned" by this entity/group: */ 602 struct cfs_rq *my_q; 603 /* cached value of my_q->h_nr_running */ 604 unsigned long runnable_weight; 605 #endif 606 607 /* 608 * Per entity load average tracking. 609 * 610 * Put into separate cache line so it does not 611 * collide with read-mostly values above. 612 */ 613 struct sched_avg avg; 614 }; 615 616 struct sched_rt_entity { 617 struct list_head run_list; 618 unsigned long timeout; 619 unsigned long watchdog_stamp; 620 unsigned int time_slice; 621 unsigned short on_rq; 622 unsigned short on_list; 623 624 struct sched_rt_entity *back; 625 #ifdef CONFIG_RT_GROUP_SCHED 626 struct sched_rt_entity *parent; 627 /* rq on which this entity is (to be) queued: */ 628 struct rt_rq *rt_rq; 629 /* rq "owned" by this entity/group: */ 630 struct rt_rq *my_q; 631 #endif 632 } __randomize_layout; 633 634 typedef bool (*dl_server_has_tasks_f)(struct sched_dl_entity *); 635 typedef struct task_struct *(*dl_server_pick_f)(struct sched_dl_entity *); 636 637 struct sched_dl_entity { 638 struct rb_node rb_node; 639 640 /* 641 * Original scheduling parameters. Copied here from sched_attr 642 * during sched_setattr(), they will remain the same until 643 * the next sched_setattr(). 644 */ 645 u64 dl_runtime; /* Maximum runtime for each instance */ 646 u64 dl_deadline; /* Relative deadline of each instance */ 647 u64 dl_period; /* Separation of two instances (period) */ 648 u64 dl_bw; /* dl_runtime / dl_period */ 649 u64 dl_density; /* dl_runtime / dl_deadline */ 650 651 /* 652 * Actual scheduling parameters. Initialized with the values above, 653 * they are continuously updated during task execution. Note that 654 * the remaining runtime could be < 0 in case we are in overrun. 655 */ 656 s64 runtime; /* Remaining runtime for this instance */ 657 u64 deadline; /* Absolute deadline for this instance */ 658 unsigned int flags; /* Specifying the scheduler behaviour */ 659 660 /* 661 * Some bool flags: 662 * 663 * @dl_throttled tells if we exhausted the runtime. If so, the 664 * task has to wait for a replenishment to be performed at the 665 * next firing of dl_timer. 666 * 667 * @dl_yielded tells if task gave up the CPU before consuming 668 * all its available runtime during the last job. 669 * 670 * @dl_non_contending tells if the task is inactive while still 671 * contributing to the active utilization. In other words, it 672 * indicates if the inactive timer has been armed and its handler 673 * has not been executed yet. This flag is useful to avoid race 674 * conditions between the inactive timer handler and the wakeup 675 * code. 676 * 677 * @dl_overrun tells if the task asked to be informed about runtime 678 * overruns. 679 * 680 * @dl_server tells if this is a server entity. 681 * 682 * @dl_defer tells if this is a deferred or regular server. For 683 * now only defer server exists. 684 * 685 * @dl_defer_armed tells if the deferrable server is waiting 686 * for the replenishment timer to activate it. 687 * 688 * @dl_server_active tells if the dlserver is active(started). 689 * dlserver is started on first cfs enqueue on an idle runqueue 690 * and is stopped when a dequeue results in 0 cfs tasks on the 691 * runqueue. In other words, dlserver is active only when cpu's 692 * runqueue has atleast one cfs task. 693 * 694 * @dl_defer_running tells if the deferrable server is actually 695 * running, skipping the defer phase. 696 */ 697 unsigned int dl_throttled : 1; 698 unsigned int dl_yielded : 1; 699 unsigned int dl_non_contending : 1; 700 unsigned int dl_overrun : 1; 701 unsigned int dl_server : 1; 702 unsigned int dl_server_active : 1; 703 unsigned int dl_defer : 1; 704 unsigned int dl_defer_armed : 1; 705 unsigned int dl_defer_running : 1; 706 unsigned int dl_server_idle : 1; 707 708 /* 709 * Bandwidth enforcement timer. Each -deadline task has its 710 * own bandwidth to be enforced, thus we need one timer per task. 711 */ 712 struct hrtimer dl_timer; 713 714 /* 715 * Inactive timer, responsible for decreasing the active utilization 716 * at the "0-lag time". When a -deadline task blocks, it contributes 717 * to GRUB's active utilization until the "0-lag time", hence a 718 * timer is needed to decrease the active utilization at the correct 719 * time. 720 */ 721 struct hrtimer inactive_timer; 722 723 /* 724 * Bits for DL-server functionality. Also see the comment near 725 * dl_server_update(). 726 * 727 * @rq the runqueue this server is for 728 * 729 * @server_has_tasks() returns true if @server_pick return a 730 * runnable task. 731 */ 732 struct rq *rq; 733 dl_server_has_tasks_f server_has_tasks; 734 dl_server_pick_f server_pick_task; 735 736 #ifdef CONFIG_RT_MUTEXES 737 /* 738 * Priority Inheritance. When a DEADLINE scheduling entity is boosted 739 * pi_se points to the donor, otherwise points to the dl_se it belongs 740 * to (the original one/itself). 741 */ 742 struct sched_dl_entity *pi_se; 743 #endif 744 }; 745 746 #ifdef CONFIG_UCLAMP_TASK 747 /* Number of utilization clamp buckets (shorter alias) */ 748 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT 749 750 /* 751 * Utilization clamp for a scheduling entity 752 * @value: clamp value "assigned" to a se 753 * @bucket_id: bucket index corresponding to the "assigned" value 754 * @active: the se is currently refcounted in a rq's bucket 755 * @user_defined: the requested clamp value comes from user-space 756 * 757 * The bucket_id is the index of the clamp bucket matching the clamp value 758 * which is pre-computed and stored to avoid expensive integer divisions from 759 * the fast path. 760 * 761 * The active bit is set whenever a task has got an "effective" value assigned, 762 * which can be different from the clamp value "requested" from user-space. 763 * This allows to know a task is refcounted in the rq's bucket corresponding 764 * to the "effective" bucket_id. 765 * 766 * The user_defined bit is set whenever a task has got a task-specific clamp 767 * value requested from userspace, i.e. the system defaults apply to this task 768 * just as a restriction. This allows to relax default clamps when a less 769 * restrictive task-specific value has been requested, thus allowing to 770 * implement a "nice" semantic. For example, a task running with a 20% 771 * default boost can still drop its own boosting to 0%. 772 */ 773 struct uclamp_se { 774 unsigned int value : bits_per(SCHED_CAPACITY_SCALE); 775 unsigned int bucket_id : bits_per(UCLAMP_BUCKETS); 776 unsigned int active : 1; 777 unsigned int user_defined : 1; 778 }; 779 #endif /* CONFIG_UCLAMP_TASK */ 780 781 union rcu_special { 782 struct { 783 u8 blocked; 784 u8 need_qs; 785 u8 exp_hint; /* Hint for performance. */ 786 u8 need_mb; /* Readers need smp_mb(). */ 787 } b; /* Bits. */ 788 u32 s; /* Set of bits. */ 789 }; 790 791 enum perf_event_task_context { 792 perf_invalid_context = -1, 793 perf_hw_context = 0, 794 perf_sw_context, 795 perf_nr_task_contexts, 796 }; 797 798 /* 799 * Number of contexts where an event can trigger: 800 * task, softirq, hardirq, nmi. 801 */ 802 #define PERF_NR_CONTEXTS 4 803 804 struct wake_q_node { 805 struct wake_q_node *next; 806 }; 807 808 struct kmap_ctrl { 809 #ifdef CONFIG_KMAP_LOCAL 810 int idx; 811 pte_t pteval[KM_MAX_IDX]; 812 #endif 813 }; 814 815 struct task_struct { 816 #ifdef CONFIG_THREAD_INFO_IN_TASK 817 /* 818 * For reasons of header soup (see current_thread_info()), this 819 * must be the first element of task_struct. 820 */ 821 struct thread_info thread_info; 822 #endif 823 unsigned int __state; 824 825 /* saved state for "spinlock sleepers" */ 826 unsigned int saved_state; 827 828 /* 829 * This begins the randomizable portion of task_struct. Only 830 * scheduling-critical items should be added above here. 831 */ 832 randomized_struct_fields_start 833 834 void *stack; 835 refcount_t usage; 836 /* Per task flags (PF_*), defined further below: */ 837 unsigned int flags; 838 unsigned int ptrace; 839 840 #ifdef CONFIG_MEM_ALLOC_PROFILING 841 struct alloc_tag *alloc_tag; 842 #endif 843 844 int on_cpu; 845 struct __call_single_node wake_entry; 846 unsigned int wakee_flips; 847 unsigned long wakee_flip_decay_ts; 848 struct task_struct *last_wakee; 849 850 /* 851 * recent_used_cpu is initially set as the last CPU used by a task 852 * that wakes affine another task. Waker/wakee relationships can 853 * push tasks around a CPU where each wakeup moves to the next one. 854 * Tracking a recently used CPU allows a quick search for a recently 855 * used CPU that may be idle. 856 */ 857 int recent_used_cpu; 858 int wake_cpu; 859 int on_rq; 860 861 int prio; 862 int static_prio; 863 int normal_prio; 864 unsigned int rt_priority; 865 866 struct sched_entity se; 867 struct sched_rt_entity rt; 868 struct sched_dl_entity dl; 869 struct sched_dl_entity *dl_server; 870 #ifdef CONFIG_SCHED_CLASS_EXT 871 struct sched_ext_entity scx; 872 #endif 873 const struct sched_class *sched_class; 874 875 #ifdef CONFIG_SCHED_CORE 876 struct rb_node core_node; 877 unsigned long core_cookie; 878 unsigned int core_occupation; 879 #endif 880 881 #ifdef CONFIG_CGROUP_SCHED 882 struct task_group *sched_task_group; 883 #endif 884 885 886 #ifdef CONFIG_UCLAMP_TASK 887 /* 888 * Clamp values requested for a scheduling entity. 889 * Must be updated with task_rq_lock() held. 890 */ 891 struct uclamp_se uclamp_req[UCLAMP_CNT]; 892 /* 893 * Effective clamp values used for a scheduling entity. 894 * Must be updated with task_rq_lock() held. 895 */ 896 struct uclamp_se uclamp[UCLAMP_CNT]; 897 #endif 898 899 struct sched_statistics stats; 900 901 #ifdef CONFIG_PREEMPT_NOTIFIERS 902 /* List of struct preempt_notifier: */ 903 struct hlist_head preempt_notifiers; 904 #endif 905 906 #ifdef CONFIG_BLK_DEV_IO_TRACE 907 unsigned int btrace_seq; 908 #endif 909 910 unsigned int policy; 911 unsigned long max_allowed_capacity; 912 int nr_cpus_allowed; 913 const cpumask_t *cpus_ptr; 914 cpumask_t *user_cpus_ptr; 915 cpumask_t cpus_mask; 916 void *migration_pending; 917 unsigned short migration_disabled; 918 unsigned short migration_flags; 919 920 #ifdef CONFIG_PREEMPT_RCU 921 int rcu_read_lock_nesting; 922 union rcu_special rcu_read_unlock_special; 923 struct list_head rcu_node_entry; 924 struct rcu_node *rcu_blocked_node; 925 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 926 927 #ifdef CONFIG_TASKS_RCU 928 unsigned long rcu_tasks_nvcsw; 929 u8 rcu_tasks_holdout; 930 u8 rcu_tasks_idx; 931 int rcu_tasks_idle_cpu; 932 struct list_head rcu_tasks_holdout_list; 933 int rcu_tasks_exit_cpu; 934 struct list_head rcu_tasks_exit_list; 935 #endif /* #ifdef CONFIG_TASKS_RCU */ 936 937 #ifdef CONFIG_TASKS_TRACE_RCU 938 int trc_reader_nesting; 939 int trc_ipi_to_cpu; 940 union rcu_special trc_reader_special; 941 struct list_head trc_holdout_list; 942 struct list_head trc_blkd_node; 943 int trc_blkd_cpu; 944 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */ 945 946 struct sched_info sched_info; 947 948 struct list_head tasks; 949 struct plist_node pushable_tasks; 950 struct rb_node pushable_dl_tasks; 951 952 struct mm_struct *mm; 953 struct mm_struct *active_mm; 954 struct address_space *faults_disabled_mapping; 955 956 int exit_state; 957 int exit_code; 958 int exit_signal; 959 /* The signal sent when the parent dies: */ 960 int pdeath_signal; 961 /* JOBCTL_*, siglock protected: */ 962 unsigned long jobctl; 963 964 /* Used for emulating ABI behavior of previous Linux versions: */ 965 unsigned int personality; 966 967 /* Scheduler bits, serialized by scheduler locks: */ 968 unsigned sched_reset_on_fork:1; 969 unsigned sched_contributes_to_load:1; 970 unsigned sched_migrated:1; 971 unsigned sched_task_hot:1; 972 973 /* Force alignment to the next boundary: */ 974 unsigned :0; 975 976 /* Unserialized, strictly 'current' */ 977 978 /* 979 * This field must not be in the scheduler word above due to wakelist 980 * queueing no longer being serialized by p->on_cpu. However: 981 * 982 * p->XXX = X; ttwu() 983 * schedule() if (p->on_rq && ..) // false 984 * smp_mb__after_spinlock(); if (smp_load_acquire(&p->on_cpu) && //true 985 * deactivate_task() ttwu_queue_wakelist()) 986 * p->on_rq = 0; p->sched_remote_wakeup = Y; 987 * 988 * guarantees all stores of 'current' are visible before 989 * ->sched_remote_wakeup gets used, so it can be in this word. 990 */ 991 unsigned sched_remote_wakeup:1; 992 #ifdef CONFIG_RT_MUTEXES 993 unsigned sched_rt_mutex:1; 994 #endif 995 996 /* Bit to tell TOMOYO we're in execve(): */ 997 unsigned in_execve:1; 998 unsigned in_iowait:1; 999 #ifndef TIF_RESTORE_SIGMASK 1000 unsigned restore_sigmask:1; 1001 #endif 1002 #ifdef CONFIG_MEMCG_V1 1003 unsigned in_user_fault:1; 1004 #endif 1005 #ifdef CONFIG_LRU_GEN 1006 /* whether the LRU algorithm may apply to this access */ 1007 unsigned in_lru_fault:1; 1008 #endif 1009 #ifdef CONFIG_COMPAT_BRK 1010 unsigned brk_randomized:1; 1011 #endif 1012 #ifdef CONFIG_CGROUPS 1013 /* disallow userland-initiated cgroup migration */ 1014 unsigned no_cgroup_migration:1; 1015 /* task is frozen/stopped (used by the cgroup freezer) */ 1016 unsigned frozen:1; 1017 #endif 1018 #ifdef CONFIG_BLK_CGROUP 1019 unsigned use_memdelay:1; 1020 #endif 1021 #ifdef CONFIG_PSI 1022 /* Stalled due to lack of memory */ 1023 unsigned in_memstall:1; 1024 #endif 1025 #ifdef CONFIG_PAGE_OWNER 1026 /* Used by page_owner=on to detect recursion in page tracking. */ 1027 unsigned in_page_owner:1; 1028 #endif 1029 #ifdef CONFIG_EVENTFD 1030 /* Recursion prevention for eventfd_signal() */ 1031 unsigned in_eventfd:1; 1032 #endif 1033 #ifdef CONFIG_ARCH_HAS_CPU_PASID 1034 unsigned pasid_activated:1; 1035 #endif 1036 #ifdef CONFIG_X86_BUS_LOCK_DETECT 1037 unsigned reported_split_lock:1; 1038 #endif 1039 #ifdef CONFIG_TASK_DELAY_ACCT 1040 /* delay due to memory thrashing */ 1041 unsigned in_thrashing:1; 1042 #endif 1043 unsigned in_nf_duplicate:1; 1044 #ifdef CONFIG_PREEMPT_RT 1045 struct netdev_xmit net_xmit; 1046 #endif 1047 unsigned long atomic_flags; /* Flags requiring atomic access. */ 1048 1049 struct restart_block restart_block; 1050 1051 pid_t pid; 1052 pid_t tgid; 1053 1054 #ifdef CONFIG_STACKPROTECTOR 1055 /* Canary value for the -fstack-protector GCC feature: */ 1056 unsigned long stack_canary; 1057 #endif 1058 /* 1059 * Pointers to the (original) parent process, youngest child, younger sibling, 1060 * older sibling, respectively. (p->father can be replaced with 1061 * p->real_parent->pid) 1062 */ 1063 1064 /* Real parent process: */ 1065 struct task_struct __rcu *real_parent; 1066 1067 /* Recipient of SIGCHLD, wait4() reports: */ 1068 struct task_struct __rcu *parent; 1069 1070 /* 1071 * Children/sibling form the list of natural children: 1072 */ 1073 struct list_head children; 1074 struct list_head sibling; 1075 struct task_struct *group_leader; 1076 1077 /* 1078 * 'ptraced' is the list of tasks this task is using ptrace() on. 1079 * 1080 * This includes both natural children and PTRACE_ATTACH targets. 1081 * 'ptrace_entry' is this task's link on the p->parent->ptraced list. 1082 */ 1083 struct list_head ptraced; 1084 struct list_head ptrace_entry; 1085 1086 /* PID/PID hash table linkage. */ 1087 struct pid *thread_pid; 1088 struct hlist_node pid_links[PIDTYPE_MAX]; 1089 struct list_head thread_node; 1090 1091 struct completion *vfork_done; 1092 1093 /* CLONE_CHILD_SETTID: */ 1094 int __user *set_child_tid; 1095 1096 /* CLONE_CHILD_CLEARTID: */ 1097 int __user *clear_child_tid; 1098 1099 /* PF_KTHREAD | PF_IO_WORKER */ 1100 void *worker_private; 1101 1102 u64 utime; 1103 u64 stime; 1104 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME 1105 u64 utimescaled; 1106 u64 stimescaled; 1107 #endif 1108 u64 gtime; 1109 struct prev_cputime prev_cputime; 1110 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1111 struct vtime vtime; 1112 #endif 1113 1114 #ifdef CONFIG_NO_HZ_FULL 1115 atomic_t tick_dep_mask; 1116 #endif 1117 /* Context switch counts: */ 1118 unsigned long nvcsw; 1119 unsigned long nivcsw; 1120 1121 /* Monotonic time in nsecs: */ 1122 u64 start_time; 1123 1124 /* Boot based time in nsecs: */ 1125 u64 start_boottime; 1126 1127 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */ 1128 unsigned long min_flt; 1129 unsigned long maj_flt; 1130 1131 /* Empty if CONFIG_POSIX_CPUTIMERS=n */ 1132 struct posix_cputimers posix_cputimers; 1133 1134 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK 1135 struct posix_cputimers_work posix_cputimers_work; 1136 #endif 1137 1138 /* Process credentials: */ 1139 1140 /* Tracer's credentials at attach: */ 1141 const struct cred __rcu *ptracer_cred; 1142 1143 /* Objective and real subjective task credentials (COW): */ 1144 const struct cred __rcu *real_cred; 1145 1146 /* Effective (overridable) subjective task credentials (COW): */ 1147 const struct cred __rcu *cred; 1148 1149 #ifdef CONFIG_KEYS 1150 /* Cached requested key. */ 1151 struct key *cached_requested_key; 1152 #endif 1153 1154 /* 1155 * executable name, excluding path. 1156 * 1157 * - normally initialized begin_new_exec() 1158 * - set it with set_task_comm() 1159 * - strscpy_pad() to ensure it is always NUL-terminated and 1160 * zero-padded 1161 * - task_lock() to ensure the operation is atomic and the name is 1162 * fully updated. 1163 */ 1164 char comm[TASK_COMM_LEN]; 1165 1166 struct nameidata *nameidata; 1167 1168 #ifdef CONFIG_SYSVIPC 1169 struct sysv_sem sysvsem; 1170 struct sysv_shm sysvshm; 1171 #endif 1172 #ifdef CONFIG_DETECT_HUNG_TASK 1173 unsigned long last_switch_count; 1174 unsigned long last_switch_time; 1175 #endif 1176 /* Filesystem information: */ 1177 struct fs_struct *fs; 1178 1179 /* Open file information: */ 1180 struct files_struct *files; 1181 1182 #ifdef CONFIG_IO_URING 1183 struct io_uring_task *io_uring; 1184 #endif 1185 1186 /* Namespaces: */ 1187 struct nsproxy *nsproxy; 1188 1189 /* Signal handlers: */ 1190 struct signal_struct *signal; 1191 struct sighand_struct __rcu *sighand; 1192 sigset_t blocked; 1193 sigset_t real_blocked; 1194 /* Restored if set_restore_sigmask() was used: */ 1195 sigset_t saved_sigmask; 1196 struct sigpending pending; 1197 unsigned long sas_ss_sp; 1198 size_t sas_ss_size; 1199 unsigned int sas_ss_flags; 1200 1201 struct callback_head *task_works; 1202 1203 #ifdef CONFIG_AUDIT 1204 #ifdef CONFIG_AUDITSYSCALL 1205 struct audit_context *audit_context; 1206 #endif 1207 kuid_t loginuid; 1208 unsigned int sessionid; 1209 #endif 1210 struct seccomp seccomp; 1211 struct syscall_user_dispatch syscall_dispatch; 1212 1213 /* Thread group tracking: */ 1214 u64 parent_exec_id; 1215 u64 self_exec_id; 1216 1217 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */ 1218 spinlock_t alloc_lock; 1219 1220 /* Protection of the PI data structures: */ 1221 raw_spinlock_t pi_lock; 1222 1223 struct wake_q_node wake_q; 1224 1225 #ifdef CONFIG_RT_MUTEXES 1226 /* PI waiters blocked on a rt_mutex held by this task: */ 1227 struct rb_root_cached pi_waiters; 1228 /* Updated under owner's pi_lock and rq lock */ 1229 struct task_struct *pi_top_task; 1230 /* Deadlock detection and priority inheritance handling: */ 1231 struct rt_mutex_waiter *pi_blocked_on; 1232 #endif 1233 1234 struct mutex *blocked_on; /* lock we're blocked on */ 1235 1236 #ifdef CONFIG_DETECT_HUNG_TASK_BLOCKER 1237 /* 1238 * Encoded lock address causing task block (lower 2 bits = type from 1239 * <linux/hung_task.h>). Accessed via hung_task_*() helpers. 1240 */ 1241 unsigned long blocker; 1242 #endif 1243 1244 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1245 int non_block_count; 1246 #endif 1247 1248 #ifdef CONFIG_TRACE_IRQFLAGS 1249 struct irqtrace_events irqtrace; 1250 unsigned int hardirq_threaded; 1251 u64 hardirq_chain_key; 1252 int softirqs_enabled; 1253 int softirq_context; 1254 int irq_config; 1255 #endif 1256 #ifdef CONFIG_PREEMPT_RT 1257 int softirq_disable_cnt; 1258 #endif 1259 1260 #ifdef CONFIG_LOCKDEP 1261 # define MAX_LOCK_DEPTH 48UL 1262 u64 curr_chain_key; 1263 int lockdep_depth; 1264 unsigned int lockdep_recursion; 1265 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1266 #endif 1267 1268 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP) 1269 unsigned int in_ubsan; 1270 #endif 1271 1272 /* Journalling filesystem info: */ 1273 void *journal_info; 1274 1275 /* Stacked block device info: */ 1276 struct bio_list *bio_list; 1277 1278 /* Stack plugging: */ 1279 struct blk_plug *plug; 1280 1281 /* VM state: */ 1282 struct reclaim_state *reclaim_state; 1283 1284 struct io_context *io_context; 1285 1286 #ifdef CONFIG_COMPACTION 1287 struct capture_control *capture_control; 1288 #endif 1289 /* Ptrace state: */ 1290 unsigned long ptrace_message; 1291 kernel_siginfo_t *last_siginfo; 1292 1293 struct task_io_accounting ioac; 1294 #ifdef CONFIG_PSI 1295 /* Pressure stall state */ 1296 unsigned int psi_flags; 1297 #endif 1298 #ifdef CONFIG_TASK_XACCT 1299 /* Accumulated RSS usage: */ 1300 u64 acct_rss_mem1; 1301 /* Accumulated virtual memory usage: */ 1302 u64 acct_vm_mem1; 1303 /* stime + utime since last update: */ 1304 u64 acct_timexpd; 1305 #endif 1306 #ifdef CONFIG_CPUSETS 1307 /* Protected by ->alloc_lock: */ 1308 nodemask_t mems_allowed; 1309 /* Sequence number to catch updates: */ 1310 seqcount_spinlock_t mems_allowed_seq; 1311 int cpuset_mem_spread_rotor; 1312 #endif 1313 #ifdef CONFIG_CGROUPS 1314 /* Control Group info protected by css_set_lock: */ 1315 struct css_set __rcu *cgroups; 1316 /* cg_list protected by css_set_lock and tsk->alloc_lock: */ 1317 struct list_head cg_list; 1318 #endif 1319 #ifdef CONFIG_X86_CPU_RESCTRL 1320 u32 closid; 1321 u32 rmid; 1322 #endif 1323 #ifdef CONFIG_FUTEX 1324 struct robust_list_head __user *robust_list; 1325 #ifdef CONFIG_COMPAT 1326 struct compat_robust_list_head __user *compat_robust_list; 1327 #endif 1328 struct list_head pi_state_list; 1329 struct futex_pi_state *pi_state_cache; 1330 struct mutex futex_exit_mutex; 1331 unsigned int futex_state; 1332 #endif 1333 #ifdef CONFIG_PERF_EVENTS 1334 u8 perf_recursion[PERF_NR_CONTEXTS]; 1335 struct perf_event_context *perf_event_ctxp; 1336 struct mutex perf_event_mutex; 1337 struct list_head perf_event_list; 1338 struct perf_ctx_data __rcu *perf_ctx_data; 1339 #endif 1340 #ifdef CONFIG_DEBUG_PREEMPT 1341 unsigned long preempt_disable_ip; 1342 #endif 1343 #ifdef CONFIG_NUMA 1344 /* Protected by alloc_lock: */ 1345 struct mempolicy *mempolicy; 1346 short il_prev; 1347 u8 il_weight; 1348 short pref_node_fork; 1349 #endif 1350 #ifdef CONFIG_NUMA_BALANCING 1351 int numa_scan_seq; 1352 unsigned int numa_scan_period; 1353 unsigned int numa_scan_period_max; 1354 int numa_preferred_nid; 1355 unsigned long numa_migrate_retry; 1356 /* Migration stamp: */ 1357 u64 node_stamp; 1358 u64 last_task_numa_placement; 1359 u64 last_sum_exec_runtime; 1360 struct callback_head numa_work; 1361 1362 /* 1363 * This pointer is only modified for current in syscall and 1364 * pagefault context (and for tasks being destroyed), so it can be read 1365 * from any of the following contexts: 1366 * - RCU read-side critical section 1367 * - current->numa_group from everywhere 1368 * - task's runqueue locked, task not running 1369 */ 1370 struct numa_group __rcu *numa_group; 1371 1372 /* 1373 * numa_faults is an array split into four regions: 1374 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer 1375 * in this precise order. 1376 * 1377 * faults_memory: Exponential decaying average of faults on a per-node 1378 * basis. Scheduling placement decisions are made based on these 1379 * counts. The values remain static for the duration of a PTE scan. 1380 * faults_cpu: Track the nodes the process was running on when a NUMA 1381 * hinting fault was incurred. 1382 * faults_memory_buffer and faults_cpu_buffer: Record faults per node 1383 * during the current scan window. When the scan completes, the counts 1384 * in faults_memory and faults_cpu decay and these values are copied. 1385 */ 1386 unsigned long *numa_faults; 1387 unsigned long total_numa_faults; 1388 1389 /* 1390 * numa_faults_locality tracks if faults recorded during the last 1391 * scan window were remote/local or failed to migrate. The task scan 1392 * period is adapted based on the locality of the faults with different 1393 * weights depending on whether they were shared or private faults 1394 */ 1395 unsigned long numa_faults_locality[3]; 1396 1397 unsigned long numa_pages_migrated; 1398 #endif /* CONFIG_NUMA_BALANCING */ 1399 1400 #ifdef CONFIG_RSEQ 1401 struct rseq __user *rseq; 1402 u32 rseq_len; 1403 u32 rseq_sig; 1404 /* 1405 * RmW on rseq_event_mask must be performed atomically 1406 * with respect to preemption. 1407 */ 1408 unsigned long rseq_event_mask; 1409 # ifdef CONFIG_DEBUG_RSEQ 1410 /* 1411 * This is a place holder to save a copy of the rseq fields for 1412 * validation of read-only fields. The struct rseq has a 1413 * variable-length array at the end, so it cannot be used 1414 * directly. Reserve a size large enough for the known fields. 1415 */ 1416 char rseq_fields[sizeof(struct rseq)]; 1417 # endif 1418 #endif 1419 1420 #ifdef CONFIG_SCHED_MM_CID 1421 int mm_cid; /* Current cid in mm */ 1422 int last_mm_cid; /* Most recent cid in mm */ 1423 int migrate_from_cpu; 1424 int mm_cid_active; /* Whether cid bitmap is active */ 1425 struct callback_head cid_work; 1426 #endif 1427 1428 struct tlbflush_unmap_batch tlb_ubc; 1429 1430 /* Cache last used pipe for splice(): */ 1431 struct pipe_inode_info *splice_pipe; 1432 1433 struct page_frag task_frag; 1434 1435 #ifdef CONFIG_TASK_DELAY_ACCT 1436 struct task_delay_info *delays; 1437 #endif 1438 1439 #ifdef CONFIG_FAULT_INJECTION 1440 int make_it_fail; 1441 unsigned int fail_nth; 1442 #endif 1443 /* 1444 * When (nr_dirtied >= nr_dirtied_pause), it's time to call 1445 * balance_dirty_pages() for a dirty throttling pause: 1446 */ 1447 int nr_dirtied; 1448 int nr_dirtied_pause; 1449 /* Start of a write-and-pause period: */ 1450 unsigned long dirty_paused_when; 1451 1452 #ifdef CONFIG_LATENCYTOP 1453 int latency_record_count; 1454 struct latency_record latency_record[LT_SAVECOUNT]; 1455 #endif 1456 /* 1457 * Time slack values; these are used to round up poll() and 1458 * select() etc timeout values. These are in nanoseconds. 1459 */ 1460 u64 timer_slack_ns; 1461 u64 default_timer_slack_ns; 1462 1463 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) 1464 unsigned int kasan_depth; 1465 #endif 1466 1467 #ifdef CONFIG_KCSAN 1468 struct kcsan_ctx kcsan_ctx; 1469 #ifdef CONFIG_TRACE_IRQFLAGS 1470 struct irqtrace_events kcsan_save_irqtrace; 1471 #endif 1472 #ifdef CONFIG_KCSAN_WEAK_MEMORY 1473 int kcsan_stack_depth; 1474 #endif 1475 #endif 1476 1477 #ifdef CONFIG_KMSAN 1478 struct kmsan_ctx kmsan_ctx; 1479 #endif 1480 1481 #if IS_ENABLED(CONFIG_KUNIT) 1482 struct kunit *kunit_test; 1483 #endif 1484 1485 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1486 /* Index of current stored address in ret_stack: */ 1487 int curr_ret_stack; 1488 int curr_ret_depth; 1489 1490 /* Stack of return addresses for return function tracing: */ 1491 unsigned long *ret_stack; 1492 1493 /* Timestamp for last schedule: */ 1494 unsigned long long ftrace_timestamp; 1495 unsigned long long ftrace_sleeptime; 1496 1497 /* 1498 * Number of functions that haven't been traced 1499 * because of depth overrun: 1500 */ 1501 atomic_t trace_overrun; 1502 1503 /* Pause tracing: */ 1504 atomic_t tracing_graph_pause; 1505 #endif 1506 1507 #ifdef CONFIG_TRACING 1508 /* Bitmask and counter of trace recursion: */ 1509 unsigned long trace_recursion; 1510 #endif /* CONFIG_TRACING */ 1511 1512 #ifdef CONFIG_KCOV 1513 /* See kernel/kcov.c for more details. */ 1514 1515 /* Coverage collection mode enabled for this task (0 if disabled): */ 1516 unsigned int kcov_mode; 1517 1518 /* Size of the kcov_area: */ 1519 unsigned int kcov_size; 1520 1521 /* Buffer for coverage collection: */ 1522 void *kcov_area; 1523 1524 /* KCOV descriptor wired with this task or NULL: */ 1525 struct kcov *kcov; 1526 1527 /* KCOV common handle for remote coverage collection: */ 1528 u64 kcov_handle; 1529 1530 /* KCOV sequence number: */ 1531 int kcov_sequence; 1532 1533 /* Collect coverage from softirq context: */ 1534 unsigned int kcov_softirq; 1535 #endif 1536 1537 #ifdef CONFIG_MEMCG_V1 1538 struct mem_cgroup *memcg_in_oom; 1539 #endif 1540 1541 #ifdef CONFIG_MEMCG 1542 /* Number of pages to reclaim on returning to userland: */ 1543 unsigned int memcg_nr_pages_over_high; 1544 1545 /* Used by memcontrol for targeted memcg charge: */ 1546 struct mem_cgroup *active_memcg; 1547 1548 /* Cache for current->cgroups->memcg->objcg lookups: */ 1549 struct obj_cgroup *objcg; 1550 #endif 1551 1552 #ifdef CONFIG_BLK_CGROUP 1553 struct gendisk *throttle_disk; 1554 #endif 1555 1556 #ifdef CONFIG_UPROBES 1557 struct uprobe_task *utask; 1558 #endif 1559 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1560 unsigned int sequential_io; 1561 unsigned int sequential_io_avg; 1562 #endif 1563 struct kmap_ctrl kmap_ctrl; 1564 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1565 unsigned long task_state_change; 1566 # ifdef CONFIG_PREEMPT_RT 1567 unsigned long saved_state_change; 1568 # endif 1569 #endif 1570 struct rcu_head rcu; 1571 refcount_t rcu_users; 1572 int pagefault_disabled; 1573 #ifdef CONFIG_MMU 1574 struct task_struct *oom_reaper_list; 1575 struct timer_list oom_reaper_timer; 1576 #endif 1577 #ifdef CONFIG_VMAP_STACK 1578 struct vm_struct *stack_vm_area; 1579 #endif 1580 #ifdef CONFIG_THREAD_INFO_IN_TASK 1581 /* A live task holds one reference: */ 1582 refcount_t stack_refcount; 1583 #endif 1584 #ifdef CONFIG_LIVEPATCH 1585 int patch_state; 1586 #endif 1587 #ifdef CONFIG_SECURITY 1588 /* Used by LSM modules for access restriction: */ 1589 void *security; 1590 #endif 1591 #ifdef CONFIG_BPF_SYSCALL 1592 /* Used by BPF task local storage */ 1593 struct bpf_local_storage __rcu *bpf_storage; 1594 /* Used for BPF run context */ 1595 struct bpf_run_ctx *bpf_ctx; 1596 #endif 1597 /* Used by BPF for per-TASK xdp storage */ 1598 struct bpf_net_context *bpf_net_context; 1599 1600 #ifdef CONFIG_KSTACK_ERASE 1601 unsigned long lowest_stack; 1602 #endif 1603 #ifdef CONFIG_KSTACK_ERASE_METRICS 1604 unsigned long prev_lowest_stack; 1605 #endif 1606 1607 #ifdef CONFIG_X86_MCE 1608 void __user *mce_vaddr; 1609 __u64 mce_kflags; 1610 u64 mce_addr; 1611 __u64 mce_ripv : 1, 1612 mce_whole_page : 1, 1613 __mce_reserved : 62; 1614 struct callback_head mce_kill_me; 1615 int mce_count; 1616 #endif 1617 1618 #ifdef CONFIG_KRETPROBES 1619 struct llist_head kretprobe_instances; 1620 #endif 1621 #ifdef CONFIG_RETHOOK 1622 struct llist_head rethooks; 1623 #endif 1624 1625 #ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH 1626 /* 1627 * If L1D flush is supported on mm context switch 1628 * then we use this callback head to queue kill work 1629 * to kill tasks that are not running on SMT disabled 1630 * cores 1631 */ 1632 struct callback_head l1d_flush_kill; 1633 #endif 1634 1635 #ifdef CONFIG_RV 1636 /* 1637 * Per-task RV monitor. Nowadays fixed in RV_PER_TASK_MONITORS. 1638 * If we find justification for more monitors, we can think 1639 * about adding more or developing a dynamic method. So far, 1640 * none of these are justified. 1641 */ 1642 union rv_task_monitor rv[RV_PER_TASK_MONITORS]; 1643 #endif 1644 1645 #ifdef CONFIG_USER_EVENTS 1646 struct user_event_mm *user_event_mm; 1647 #endif 1648 1649 /* CPU-specific state of this task: */ 1650 struct thread_struct thread; 1651 1652 /* 1653 * New fields for task_struct should be added above here, so that 1654 * they are included in the randomized portion of task_struct. 1655 */ 1656 randomized_struct_fields_end 1657 } __attribute__ ((aligned (64))); 1658 1659 #ifdef CONFIG_SCHED_PROXY_EXEC 1660 DECLARE_STATIC_KEY_TRUE(__sched_proxy_exec); 1661 static inline bool sched_proxy_exec(void) 1662 { 1663 return static_branch_likely(&__sched_proxy_exec); 1664 } 1665 #else 1666 static inline bool sched_proxy_exec(void) 1667 { 1668 return false; 1669 } 1670 #endif 1671 1672 #define TASK_REPORT_IDLE (TASK_REPORT + 1) 1673 #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1) 1674 1675 static inline unsigned int __task_state_index(unsigned int tsk_state, 1676 unsigned int tsk_exit_state) 1677 { 1678 unsigned int state = (tsk_state | tsk_exit_state) & TASK_REPORT; 1679 1680 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX); 1681 1682 if ((tsk_state & TASK_IDLE) == TASK_IDLE) 1683 state = TASK_REPORT_IDLE; 1684 1685 /* 1686 * We're lying here, but rather than expose a completely new task state 1687 * to userspace, we can make this appear as if the task has gone through 1688 * a regular rt_mutex_lock() call. 1689 * Report frozen tasks as uninterruptible. 1690 */ 1691 if ((tsk_state & TASK_RTLOCK_WAIT) || (tsk_state & TASK_FROZEN)) 1692 state = TASK_UNINTERRUPTIBLE; 1693 1694 return fls(state); 1695 } 1696 1697 static inline unsigned int task_state_index(struct task_struct *tsk) 1698 { 1699 return __task_state_index(READ_ONCE(tsk->__state), tsk->exit_state); 1700 } 1701 1702 static inline char task_index_to_char(unsigned int state) 1703 { 1704 static const char state_char[] = "RSDTtXZPI"; 1705 1706 BUILD_BUG_ON(TASK_REPORT_MAX * 2 != 1 << (sizeof(state_char) - 1)); 1707 1708 return state_char[state]; 1709 } 1710 1711 static inline char task_state_to_char(struct task_struct *tsk) 1712 { 1713 return task_index_to_char(task_state_index(tsk)); 1714 } 1715 1716 extern struct pid *cad_pid; 1717 1718 /* 1719 * Per process flags 1720 */ 1721 #define PF_VCPU 0x00000001 /* I'm a virtual CPU */ 1722 #define PF_IDLE 0x00000002 /* I am an IDLE thread */ 1723 #define PF_EXITING 0x00000004 /* Getting shut down */ 1724 #define PF_POSTCOREDUMP 0x00000008 /* Coredumps should ignore this task */ 1725 #define PF_IO_WORKER 0x00000010 /* Task is an IO worker */ 1726 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 1727 #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */ 1728 #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */ 1729 #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */ 1730 #define PF_DUMPCORE 0x00000200 /* Dumped core */ 1731 #define PF_SIGNALED 0x00000400 /* Killed by a signal */ 1732 #define PF_MEMALLOC 0x00000800 /* Allocating memory to free memory. See memalloc_noreclaim_save() */ 1733 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */ 1734 #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */ 1735 #define PF_USER_WORKER 0x00004000 /* Kernel thread cloned from userspace thread */ 1736 #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */ 1737 #define PF_KCOMPACTD 0x00010000 /* I am kcompactd */ 1738 #define PF_KSWAPD 0x00020000 /* I am kswapd */ 1739 #define PF_MEMALLOC_NOFS 0x00040000 /* All allocations inherit GFP_NOFS. See memalloc_nfs_save() */ 1740 #define PF_MEMALLOC_NOIO 0x00080000 /* All allocations inherit GFP_NOIO. See memalloc_noio_save() */ 1741 #define PF_LOCAL_THROTTLE 0x00100000 /* Throttle writes only against the bdi I write to, 1742 * I am cleaning dirty pages from some other bdi. */ 1743 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 1744 #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */ 1745 #define PF__HOLE__00800000 0x00800000 1746 #define PF__HOLE__01000000 0x01000000 1747 #define PF__HOLE__02000000 0x02000000 1748 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */ 1749 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 1750 #define PF_MEMALLOC_PIN 0x10000000 /* Allocations constrained to zones which allow long term pinning. 1751 * See memalloc_pin_save() */ 1752 #define PF_BLOCK_TS 0x20000000 /* plug has ts that needs updating */ 1753 #define PF__HOLE__40000000 0x40000000 1754 #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */ 1755 1756 /* 1757 * Only the _current_ task can read/write to tsk->flags, but other 1758 * tasks can access tsk->flags in readonly mode for example 1759 * with tsk_used_math (like during threaded core dumping). 1760 * There is however an exception to this rule during ptrace 1761 * or during fork: the ptracer task is allowed to write to the 1762 * child->flags of its traced child (same goes for fork, the parent 1763 * can write to the child->flags), because we're guaranteed the 1764 * child is not running and in turn not changing child->flags 1765 * at the same time the parent does it. 1766 */ 1767 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1768 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1769 #define clear_used_math() clear_stopped_child_used_math(current) 1770 #define set_used_math() set_stopped_child_used_math(current) 1771 1772 #define conditional_stopped_child_used_math(condition, child) \ 1773 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1774 1775 #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current) 1776 1777 #define copy_to_stopped_child_used_math(child) \ 1778 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1779 1780 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1781 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1782 #define used_math() tsk_used_math(current) 1783 1784 static __always_inline bool is_percpu_thread(void) 1785 { 1786 return (current->flags & PF_NO_SETAFFINITY) && 1787 (current->nr_cpus_allowed == 1); 1788 } 1789 1790 /* Per-process atomic flags. */ 1791 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */ 1792 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */ 1793 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */ 1794 #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */ 1795 #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/ 1796 #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */ 1797 #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */ 1798 #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */ 1799 1800 #define TASK_PFA_TEST(name, func) \ 1801 static inline bool task_##func(struct task_struct *p) \ 1802 { return test_bit(PFA_##name, &p->atomic_flags); } 1803 1804 #define TASK_PFA_SET(name, func) \ 1805 static inline void task_set_##func(struct task_struct *p) \ 1806 { set_bit(PFA_##name, &p->atomic_flags); } 1807 1808 #define TASK_PFA_CLEAR(name, func) \ 1809 static inline void task_clear_##func(struct task_struct *p) \ 1810 { clear_bit(PFA_##name, &p->atomic_flags); } 1811 1812 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs) 1813 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs) 1814 1815 TASK_PFA_TEST(SPREAD_PAGE, spread_page) 1816 TASK_PFA_SET(SPREAD_PAGE, spread_page) 1817 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page) 1818 1819 TASK_PFA_TEST(SPREAD_SLAB, spread_slab) 1820 TASK_PFA_SET(SPREAD_SLAB, spread_slab) 1821 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab) 1822 1823 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable) 1824 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable) 1825 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable) 1826 1827 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1828 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1829 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1830 1831 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1832 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1833 1834 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable) 1835 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable) 1836 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable) 1837 1838 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1839 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1840 1841 static inline void 1842 current_restore_flags(unsigned long orig_flags, unsigned long flags) 1843 { 1844 current->flags &= ~flags; 1845 current->flags |= orig_flags & flags; 1846 } 1847 1848 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 1849 extern int task_can_attach(struct task_struct *p); 1850 extern int dl_bw_alloc(int cpu, u64 dl_bw); 1851 extern void dl_bw_free(int cpu, u64 dl_bw); 1852 1853 /* do_set_cpus_allowed() - consider using set_cpus_allowed_ptr() instead */ 1854 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask); 1855 1856 /** 1857 * set_cpus_allowed_ptr - set CPU affinity mask of a task 1858 * @p: the task 1859 * @new_mask: CPU affinity mask 1860 * 1861 * Return: zero if successful, or a negative error code 1862 */ 1863 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask); 1864 extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node); 1865 extern void release_user_cpus_ptr(struct task_struct *p); 1866 extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask); 1867 extern void force_compatible_cpus_allowed_ptr(struct task_struct *p); 1868 extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p); 1869 1870 extern int yield_to(struct task_struct *p, bool preempt); 1871 extern void set_user_nice(struct task_struct *p, long nice); 1872 extern int task_prio(const struct task_struct *p); 1873 1874 /** 1875 * task_nice - return the nice value of a given task. 1876 * @p: the task in question. 1877 * 1878 * Return: The nice value [ -20 ... 0 ... 19 ]. 1879 */ 1880 static inline int task_nice(const struct task_struct *p) 1881 { 1882 return PRIO_TO_NICE((p)->static_prio); 1883 } 1884 1885 extern int can_nice(const struct task_struct *p, const int nice); 1886 extern int task_curr(const struct task_struct *p); 1887 extern int idle_cpu(int cpu); 1888 extern int available_idle_cpu(int cpu); 1889 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *); 1890 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *); 1891 extern void sched_set_fifo(struct task_struct *p); 1892 extern void sched_set_fifo_low(struct task_struct *p); 1893 extern void sched_set_normal(struct task_struct *p, int nice); 1894 extern int sched_setattr(struct task_struct *, const struct sched_attr *); 1895 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *); 1896 extern struct task_struct *idle_task(int cpu); 1897 1898 /** 1899 * is_idle_task - is the specified task an idle task? 1900 * @p: the task in question. 1901 * 1902 * Return: 1 if @p is an idle task. 0 otherwise. 1903 */ 1904 static __always_inline bool is_idle_task(const struct task_struct *p) 1905 { 1906 return !!(p->flags & PF_IDLE); 1907 } 1908 1909 extern struct task_struct *curr_task(int cpu); 1910 extern void ia64_set_curr_task(int cpu, struct task_struct *p); 1911 1912 void yield(void); 1913 1914 union thread_union { 1915 struct task_struct task; 1916 #ifndef CONFIG_THREAD_INFO_IN_TASK 1917 struct thread_info thread_info; 1918 #endif 1919 unsigned long stack[THREAD_SIZE/sizeof(long)]; 1920 }; 1921 1922 #ifndef CONFIG_THREAD_INFO_IN_TASK 1923 extern struct thread_info init_thread_info; 1924 #endif 1925 1926 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)]; 1927 1928 #ifdef CONFIG_THREAD_INFO_IN_TASK 1929 # define task_thread_info(task) (&(task)->thread_info) 1930 #else 1931 # define task_thread_info(task) ((struct thread_info *)(task)->stack) 1932 #endif 1933 1934 /* 1935 * find a task by one of its numerical ids 1936 * 1937 * find_task_by_pid_ns(): 1938 * finds a task by its pid in the specified namespace 1939 * find_task_by_vpid(): 1940 * finds a task by its virtual pid 1941 * 1942 * see also find_vpid() etc in include/linux/pid.h 1943 */ 1944 1945 extern struct task_struct *find_task_by_vpid(pid_t nr); 1946 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns); 1947 1948 /* 1949 * find a task by its virtual pid and get the task struct 1950 */ 1951 extern struct task_struct *find_get_task_by_vpid(pid_t nr); 1952 1953 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 1954 extern int wake_up_process(struct task_struct *tsk); 1955 extern void wake_up_new_task(struct task_struct *tsk); 1956 1957 extern void kick_process(struct task_struct *tsk); 1958 1959 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); 1960 #define set_task_comm(tsk, from) ({ \ 1961 BUILD_BUG_ON(sizeof(from) != TASK_COMM_LEN); \ 1962 __set_task_comm(tsk, from, false); \ 1963 }) 1964 1965 /* 1966 * - Why not use task_lock()? 1967 * User space can randomly change their names anyway, so locking for readers 1968 * doesn't make sense. For writers, locking is probably necessary, as a race 1969 * condition could lead to long-term mixed results. 1970 * The strscpy_pad() in __set_task_comm() can ensure that the task comm is 1971 * always NUL-terminated and zero-padded. Therefore the race condition between 1972 * reader and writer is not an issue. 1973 * 1974 * - BUILD_BUG_ON() can help prevent the buf from being truncated. 1975 * Since the callers don't perform any return value checks, this safeguard is 1976 * necessary. 1977 */ 1978 #define get_task_comm(buf, tsk) ({ \ 1979 BUILD_BUG_ON(sizeof(buf) < TASK_COMM_LEN); \ 1980 strscpy_pad(buf, (tsk)->comm); \ 1981 buf; \ 1982 }) 1983 1984 static __always_inline void scheduler_ipi(void) 1985 { 1986 /* 1987 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting 1988 * TIF_NEED_RESCHED remotely (for the first time) will also send 1989 * this IPI. 1990 */ 1991 preempt_fold_need_resched(); 1992 } 1993 1994 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state); 1995 1996 /* 1997 * Set thread flags in other task's structures. 1998 * See asm/thread_info.h for TIF_xxxx flags available: 1999 */ 2000 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 2001 { 2002 set_ti_thread_flag(task_thread_info(tsk), flag); 2003 } 2004 2005 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2006 { 2007 clear_ti_thread_flag(task_thread_info(tsk), flag); 2008 } 2009 2010 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag, 2011 bool value) 2012 { 2013 update_ti_thread_flag(task_thread_info(tsk), flag, value); 2014 } 2015 2016 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 2017 { 2018 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 2019 } 2020 2021 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2022 { 2023 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 2024 } 2025 2026 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 2027 { 2028 return test_ti_thread_flag(task_thread_info(tsk), flag); 2029 } 2030 2031 static inline void set_tsk_need_resched(struct task_struct *tsk) 2032 { 2033 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2034 } 2035 2036 static inline void clear_tsk_need_resched(struct task_struct *tsk) 2037 { 2038 atomic_long_andnot(_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY, 2039 (atomic_long_t *)&task_thread_info(tsk)->flags); 2040 } 2041 2042 static inline int test_tsk_need_resched(struct task_struct *tsk) 2043 { 2044 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 2045 } 2046 2047 /* 2048 * cond_resched() and cond_resched_lock(): latency reduction via 2049 * explicit rescheduling in places that are safe. The return 2050 * value indicates whether a reschedule was done in fact. 2051 * cond_resched_lock() will drop the spinlock before scheduling, 2052 */ 2053 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) 2054 extern int __cond_resched(void); 2055 2056 #if defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL) 2057 2058 DECLARE_STATIC_CALL(cond_resched, __cond_resched); 2059 2060 static __always_inline int _cond_resched(void) 2061 { 2062 return static_call_mod(cond_resched)(); 2063 } 2064 2065 #elif defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY) 2066 2067 extern int dynamic_cond_resched(void); 2068 2069 static __always_inline int _cond_resched(void) 2070 { 2071 return dynamic_cond_resched(); 2072 } 2073 2074 #else /* !CONFIG_PREEMPTION */ 2075 2076 static inline int _cond_resched(void) 2077 { 2078 return __cond_resched(); 2079 } 2080 2081 #endif /* PREEMPT_DYNAMIC && CONFIG_HAVE_PREEMPT_DYNAMIC_CALL */ 2082 2083 #else /* CONFIG_PREEMPTION && !CONFIG_PREEMPT_DYNAMIC */ 2084 2085 static inline int _cond_resched(void) 2086 { 2087 return 0; 2088 } 2089 2090 #endif /* !CONFIG_PREEMPTION || CONFIG_PREEMPT_DYNAMIC */ 2091 2092 #define cond_resched() ({ \ 2093 __might_resched(__FILE__, __LINE__, 0); \ 2094 _cond_resched(); \ 2095 }) 2096 2097 extern int __cond_resched_lock(spinlock_t *lock); 2098 extern int __cond_resched_rwlock_read(rwlock_t *lock); 2099 extern int __cond_resched_rwlock_write(rwlock_t *lock); 2100 2101 #define MIGHT_RESCHED_RCU_SHIFT 8 2102 #define MIGHT_RESCHED_PREEMPT_MASK ((1U << MIGHT_RESCHED_RCU_SHIFT) - 1) 2103 2104 #ifndef CONFIG_PREEMPT_RT 2105 /* 2106 * Non RT kernels have an elevated preempt count due to the held lock, 2107 * but are not allowed to be inside a RCU read side critical section 2108 */ 2109 # define PREEMPT_LOCK_RESCHED_OFFSETS PREEMPT_LOCK_OFFSET 2110 #else 2111 /* 2112 * spin/rw_lock() on RT implies rcu_read_lock(). The might_sleep() check in 2113 * cond_resched*lock() has to take that into account because it checks for 2114 * preempt_count() and rcu_preempt_depth(). 2115 */ 2116 # define PREEMPT_LOCK_RESCHED_OFFSETS \ 2117 (PREEMPT_LOCK_OFFSET + (1U << MIGHT_RESCHED_RCU_SHIFT)) 2118 #endif 2119 2120 #define cond_resched_lock(lock) ({ \ 2121 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ 2122 __cond_resched_lock(lock); \ 2123 }) 2124 2125 #define cond_resched_rwlock_read(lock) ({ \ 2126 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ 2127 __cond_resched_rwlock_read(lock); \ 2128 }) 2129 2130 #define cond_resched_rwlock_write(lock) ({ \ 2131 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ 2132 __cond_resched_rwlock_write(lock); \ 2133 }) 2134 2135 #ifndef CONFIG_PREEMPT_RT 2136 static inline struct mutex *__get_task_blocked_on(struct task_struct *p) 2137 { 2138 struct mutex *m = p->blocked_on; 2139 2140 if (m) 2141 lockdep_assert_held_once(&m->wait_lock); 2142 return m; 2143 } 2144 2145 static inline void __set_task_blocked_on(struct task_struct *p, struct mutex *m) 2146 { 2147 WARN_ON_ONCE(!m); 2148 /* The task should only be setting itself as blocked */ 2149 WARN_ON_ONCE(p != current); 2150 /* Currently we serialize blocked_on under the mutex::wait_lock */ 2151 lockdep_assert_held_once(&m->wait_lock); 2152 /* 2153 * Check ensure we don't overwrite existing mutex value 2154 * with a different mutex. Note, setting it to the same 2155 * lock repeatedly is ok. 2156 */ 2157 WARN_ON_ONCE(p->blocked_on && p->blocked_on != m); 2158 p->blocked_on = m; 2159 } 2160 2161 static inline void set_task_blocked_on(struct task_struct *p, struct mutex *m) 2162 { 2163 guard(raw_spinlock_irqsave)(&m->wait_lock); 2164 __set_task_blocked_on(p, m); 2165 } 2166 2167 static inline void __clear_task_blocked_on(struct task_struct *p, struct mutex *m) 2168 { 2169 WARN_ON_ONCE(!m); 2170 /* Currently we serialize blocked_on under the mutex::wait_lock */ 2171 lockdep_assert_held_once(&m->wait_lock); 2172 /* 2173 * There may be cases where we re-clear already cleared 2174 * blocked_on relationships, but make sure we are not 2175 * clearing the relationship with a different lock. 2176 */ 2177 WARN_ON_ONCE(m && p->blocked_on && p->blocked_on != m); 2178 p->blocked_on = NULL; 2179 } 2180 2181 static inline void clear_task_blocked_on(struct task_struct *p, struct mutex *m) 2182 { 2183 guard(raw_spinlock_irqsave)(&m->wait_lock); 2184 __clear_task_blocked_on(p, m); 2185 } 2186 #else 2187 static inline void __clear_task_blocked_on(struct task_struct *p, struct rt_mutex *m) 2188 { 2189 } 2190 2191 static inline void clear_task_blocked_on(struct task_struct *p, struct rt_mutex *m) 2192 { 2193 } 2194 #endif /* !CONFIG_PREEMPT_RT */ 2195 2196 static __always_inline bool need_resched(void) 2197 { 2198 return unlikely(tif_need_resched()); 2199 } 2200 2201 /* 2202 * Wrappers for p->thread_info->cpu access. No-op on UP. 2203 */ 2204 #ifdef CONFIG_SMP 2205 2206 static inline unsigned int task_cpu(const struct task_struct *p) 2207 { 2208 return READ_ONCE(task_thread_info(p)->cpu); 2209 } 2210 2211 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 2212 2213 #else 2214 2215 static inline unsigned int task_cpu(const struct task_struct *p) 2216 { 2217 return 0; 2218 } 2219 2220 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 2221 { 2222 } 2223 2224 #endif /* CONFIG_SMP */ 2225 2226 static inline bool task_is_runnable(struct task_struct *p) 2227 { 2228 return p->on_rq && !p->se.sched_delayed; 2229 } 2230 2231 extern bool sched_task_on_rq(struct task_struct *p); 2232 extern unsigned long get_wchan(struct task_struct *p); 2233 extern struct task_struct *cpu_curr_snapshot(int cpu); 2234 2235 /* 2236 * In order to reduce various lock holder preemption latencies provide an 2237 * interface to see if a vCPU is currently running or not. 2238 * 2239 * This allows us to terminate optimistic spin loops and block, analogous to 2240 * the native optimistic spin heuristic of testing if the lock owner task is 2241 * running or not. 2242 */ 2243 #ifndef vcpu_is_preempted 2244 static inline bool vcpu_is_preempted(int cpu) 2245 { 2246 return false; 2247 } 2248 #endif 2249 2250 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 2251 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 2252 2253 #ifndef TASK_SIZE_OF 2254 #define TASK_SIZE_OF(tsk) TASK_SIZE 2255 #endif 2256 2257 static inline bool owner_on_cpu(struct task_struct *owner) 2258 { 2259 /* 2260 * As lock holder preemption issue, we both skip spinning if 2261 * task is not on cpu or its cpu is preempted 2262 */ 2263 return READ_ONCE(owner->on_cpu) && !vcpu_is_preempted(task_cpu(owner)); 2264 } 2265 2266 /* Returns effective CPU energy utilization, as seen by the scheduler */ 2267 unsigned long sched_cpu_util(int cpu); 2268 2269 #ifdef CONFIG_SCHED_CORE 2270 extern void sched_core_free(struct task_struct *tsk); 2271 extern void sched_core_fork(struct task_struct *p); 2272 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type, 2273 unsigned long uaddr); 2274 extern int sched_core_idle_cpu(int cpu); 2275 #else 2276 static inline void sched_core_free(struct task_struct *tsk) { } 2277 static inline void sched_core_fork(struct task_struct *p) { } 2278 static inline int sched_core_idle_cpu(int cpu) { return idle_cpu(cpu); } 2279 #endif 2280 2281 extern void sched_set_stop_task(int cpu, struct task_struct *stop); 2282 2283 #ifdef CONFIG_MEM_ALLOC_PROFILING 2284 static __always_inline struct alloc_tag *alloc_tag_save(struct alloc_tag *tag) 2285 { 2286 swap(current->alloc_tag, tag); 2287 return tag; 2288 } 2289 2290 static __always_inline void alloc_tag_restore(struct alloc_tag *tag, struct alloc_tag *old) 2291 { 2292 #ifdef CONFIG_MEM_ALLOC_PROFILING_DEBUG 2293 WARN(current->alloc_tag != tag, "current->alloc_tag was changed:\n"); 2294 #endif 2295 current->alloc_tag = old; 2296 } 2297 #else 2298 #define alloc_tag_save(_tag) NULL 2299 #define alloc_tag_restore(_tag, _old) do {} while (0) 2300 #endif 2301 2302 #endif 2303