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 <linux/unwind_deferred_types.h> 51 #include <asm/kmap_size.h> 52 #ifndef COMPILE_OFFSETS 53 #include <generated/rq-offsets.h> 54 #endif 55 56 /* task_struct member predeclarations (sorted alphabetically): */ 57 struct audit_context; 58 struct bio_list; 59 struct blk_plug; 60 struct bpf_local_storage; 61 struct bpf_run_ctx; 62 struct bpf_net_context; 63 struct capture_control; 64 struct cfs_rq; 65 struct fs_struct; 66 struct futex_pi_state; 67 struct io_context; 68 struct io_uring_task; 69 struct mempolicy; 70 struct nameidata; 71 struct nsproxy; 72 struct perf_event_context; 73 struct perf_ctx_data; 74 struct pid_namespace; 75 struct pipe_inode_info; 76 struct rcu_node; 77 struct reclaim_state; 78 struct robust_list_head; 79 struct root_domain; 80 struct rq; 81 struct sched_attr; 82 struct sched_dl_entity; 83 struct seq_file; 84 struct sighand_struct; 85 struct signal_struct; 86 struct task_delay_info; 87 struct task_group; 88 struct task_struct; 89 struct user_event_mm; 90 91 #include <linux/sched/ext.h> 92 93 /* 94 * Task state bitmask. NOTE! These bits are also 95 * encoded in fs/proc/array.c: get_task_state(). 96 * 97 * We have two separate sets of flags: task->__state 98 * is about runnability, while task->exit_state are 99 * about the task exiting. Confusing, but this way 100 * modifying one set can't modify the other one by 101 * mistake. 102 */ 103 104 /* Used in tsk->__state: */ 105 #define TASK_RUNNING 0x00000000 106 #define TASK_INTERRUPTIBLE 0x00000001 107 #define TASK_UNINTERRUPTIBLE 0x00000002 108 #define __TASK_STOPPED 0x00000004 109 #define __TASK_TRACED 0x00000008 110 /* Used in tsk->exit_state: */ 111 #define EXIT_DEAD 0x00000010 112 #define EXIT_ZOMBIE 0x00000020 113 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD) 114 /* Used in tsk->__state again: */ 115 #define TASK_PARKED 0x00000040 116 #define TASK_DEAD 0x00000080 117 #define TASK_WAKEKILL 0x00000100 118 #define TASK_WAKING 0x00000200 119 #define TASK_NOLOAD 0x00000400 120 #define TASK_NEW 0x00000800 121 #define TASK_RTLOCK_WAIT 0x00001000 122 #define TASK_FREEZABLE 0x00002000 123 #define __TASK_FREEZABLE_UNSAFE (0x00004000 * IS_ENABLED(CONFIG_LOCKDEP)) 124 #define TASK_FROZEN 0x00008000 125 #define TASK_STATE_MAX 0x00010000 126 127 #define TASK_ANY (TASK_STATE_MAX-1) 128 129 /* 130 * DO NOT ADD ANY NEW USERS ! 131 */ 132 #define TASK_FREEZABLE_UNSAFE (TASK_FREEZABLE | __TASK_FREEZABLE_UNSAFE) 133 134 /* Convenience macros for the sake of set_current_state: */ 135 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 136 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 137 #define TASK_TRACED __TASK_TRACED 138 139 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD) 140 141 /* Convenience macros for the sake of wake_up(): */ 142 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 143 144 /* get_task_state(): */ 145 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 146 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 147 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \ 148 TASK_PARKED) 149 150 #define task_is_running(task) (READ_ONCE((task)->__state) == TASK_RUNNING) 151 152 #define task_is_traced(task) ((READ_ONCE(task->jobctl) & JOBCTL_TRACED) != 0) 153 #define task_is_stopped(task) ((READ_ONCE(task->jobctl) & JOBCTL_STOPPED) != 0) 154 #define task_is_stopped_or_traced(task) ((READ_ONCE(task->jobctl) & (JOBCTL_STOPPED | JOBCTL_TRACED)) != 0) 155 156 /* 157 * Special states are those that do not use the normal wait-loop pattern. See 158 * the comment with set_special_state(). 159 */ 160 #define is_special_task_state(state) \ 161 ((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | \ 162 TASK_DEAD | TASK_FROZEN)) 163 164 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 165 # define debug_normal_state_change(state_value) \ 166 do { \ 167 WARN_ON_ONCE(is_special_task_state(state_value)); \ 168 current->task_state_change = _THIS_IP_; \ 169 } while (0) 170 171 # define debug_special_state_change(state_value) \ 172 do { \ 173 WARN_ON_ONCE(!is_special_task_state(state_value)); \ 174 current->task_state_change = _THIS_IP_; \ 175 } while (0) 176 177 # define debug_rtlock_wait_set_state() \ 178 do { \ 179 current->saved_state_change = current->task_state_change;\ 180 current->task_state_change = _THIS_IP_; \ 181 } while (0) 182 183 # define debug_rtlock_wait_restore_state() \ 184 do { \ 185 current->task_state_change = current->saved_state_change;\ 186 } while (0) 187 188 #else 189 # define debug_normal_state_change(cond) do { } while (0) 190 # define debug_special_state_change(cond) do { } while (0) 191 # define debug_rtlock_wait_set_state() do { } while (0) 192 # define debug_rtlock_wait_restore_state() do { } while (0) 193 #endif 194 195 #define trace_set_current_state(state_value) \ 196 do { \ 197 if (tracepoint_enabled(sched_set_state_tp)) \ 198 __trace_set_current_state(state_value); \ 199 } while (0) 200 201 /* 202 * set_current_state() includes a barrier so that the write of current->__state 203 * is correctly serialised wrt the caller's subsequent test of whether to 204 * actually sleep: 205 * 206 * for (;;) { 207 * set_current_state(TASK_UNINTERRUPTIBLE); 208 * if (CONDITION) 209 * break; 210 * 211 * schedule(); 212 * } 213 * __set_current_state(TASK_RUNNING); 214 * 215 * If the caller does not need such serialisation (because, for instance, the 216 * CONDITION test and condition change and wakeup are under the same lock) then 217 * use __set_current_state(). 218 * 219 * The above is typically ordered against the wakeup, which does: 220 * 221 * CONDITION = 1; 222 * wake_up_state(p, TASK_UNINTERRUPTIBLE); 223 * 224 * where wake_up_state()/try_to_wake_up() executes a full memory barrier before 225 * accessing p->__state. 226 * 227 * Wakeup will do: if (@state & p->__state) p->__state = TASK_RUNNING, that is, 228 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a 229 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING). 230 * 231 * However, with slightly different timing the wakeup TASK_RUNNING store can 232 * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not 233 * a problem either because that will result in one extra go around the loop 234 * and our @cond test will save the day. 235 * 236 * Also see the comments of try_to_wake_up(). 237 */ 238 #define __set_current_state(state_value) \ 239 do { \ 240 debug_normal_state_change((state_value)); \ 241 trace_set_current_state(state_value); \ 242 WRITE_ONCE(current->__state, (state_value)); \ 243 } while (0) 244 245 #define set_current_state(state_value) \ 246 do { \ 247 debug_normal_state_change((state_value)); \ 248 trace_set_current_state(state_value); \ 249 smp_store_mb(current->__state, (state_value)); \ 250 } while (0) 251 252 /* 253 * set_special_state() should be used for those states when the blocking task 254 * can not use the regular condition based wait-loop. In that case we must 255 * serialize against wakeups such that any possible in-flight TASK_RUNNING 256 * stores will not collide with our state change. 257 */ 258 #define set_special_state(state_value) \ 259 do { \ 260 unsigned long flags; /* may shadow */ \ 261 \ 262 raw_spin_lock_irqsave(¤t->pi_lock, flags); \ 263 debug_special_state_change((state_value)); \ 264 trace_set_current_state(state_value); \ 265 WRITE_ONCE(current->__state, (state_value)); \ 266 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \ 267 } while (0) 268 269 /* 270 * PREEMPT_RT specific variants for "sleeping" spin/rwlocks 271 * 272 * RT's spin/rwlock substitutions are state preserving. The state of the 273 * task when blocking on the lock is saved in task_struct::saved_state and 274 * restored after the lock has been acquired. These operations are 275 * serialized by task_struct::pi_lock against try_to_wake_up(). Any non RT 276 * lock related wakeups while the task is blocked on the lock are 277 * redirected to operate on task_struct::saved_state to ensure that these 278 * are not dropped. On restore task_struct::saved_state is set to 279 * TASK_RUNNING so any wakeup attempt redirected to saved_state will fail. 280 * 281 * The lock operation looks like this: 282 * 283 * current_save_and_set_rtlock_wait_state(); 284 * for (;;) { 285 * if (try_lock()) 286 * break; 287 * raw_spin_unlock_irq(&lock->wait_lock); 288 * schedule_rtlock(); 289 * raw_spin_lock_irq(&lock->wait_lock); 290 * set_current_state(TASK_RTLOCK_WAIT); 291 * } 292 * current_restore_rtlock_saved_state(); 293 */ 294 #define current_save_and_set_rtlock_wait_state() \ 295 do { \ 296 lockdep_assert_irqs_disabled(); \ 297 raw_spin_lock(¤t->pi_lock); \ 298 current->saved_state = current->__state; \ 299 debug_rtlock_wait_set_state(); \ 300 trace_set_current_state(TASK_RTLOCK_WAIT); \ 301 WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT); \ 302 raw_spin_unlock(¤t->pi_lock); \ 303 } while (0); 304 305 #define current_restore_rtlock_saved_state() \ 306 do { \ 307 lockdep_assert_irqs_disabled(); \ 308 raw_spin_lock(¤t->pi_lock); \ 309 debug_rtlock_wait_restore_state(); \ 310 trace_set_current_state(current->saved_state); \ 311 WRITE_ONCE(current->__state, current->saved_state); \ 312 current->saved_state = TASK_RUNNING; \ 313 raw_spin_unlock(¤t->pi_lock); \ 314 } while (0); 315 316 #define get_current_state() READ_ONCE(current->__state) 317 318 /* 319 * Define the task command name length as enum, then it can be visible to 320 * BPF programs. 321 */ 322 enum { 323 TASK_COMM_LEN = 16, 324 }; 325 326 extern void sched_tick(void); 327 328 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 329 330 extern long schedule_timeout(long timeout); 331 extern long schedule_timeout_interruptible(long timeout); 332 extern long schedule_timeout_killable(long timeout); 333 extern long schedule_timeout_uninterruptible(long timeout); 334 extern long schedule_timeout_idle(long timeout); 335 asmlinkage void schedule(void); 336 extern void schedule_preempt_disabled(void); 337 asmlinkage void preempt_schedule_irq(void); 338 #ifdef CONFIG_PREEMPT_RT 339 extern void schedule_rtlock(void); 340 #endif 341 342 extern int __must_check io_schedule_prepare(void); 343 extern void io_schedule_finish(int token); 344 extern long io_schedule_timeout(long timeout); 345 extern void io_schedule(void); 346 347 /* wrapper functions to trace from this header file */ 348 DECLARE_TRACEPOINT(sched_set_state_tp); 349 extern void __trace_set_current_state(int state_value); 350 DECLARE_TRACEPOINT(sched_set_need_resched_tp); 351 extern void __trace_set_need_resched(struct task_struct *curr, int tif); 352 353 /** 354 * struct prev_cputime - snapshot of system and user cputime 355 * @utime: time spent in user mode 356 * @stime: time spent in system mode 357 * @lock: protects the above two fields 358 * 359 * Stores previous user/system time values such that we can guarantee 360 * monotonicity. 361 */ 362 struct prev_cputime { 363 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 364 u64 utime; 365 u64 stime; 366 raw_spinlock_t lock; 367 #endif 368 }; 369 370 enum vtime_state { 371 /* Task is sleeping or running in a CPU with VTIME inactive: */ 372 VTIME_INACTIVE = 0, 373 /* Task is idle */ 374 VTIME_IDLE, 375 /* Task runs in kernelspace in a CPU with VTIME active: */ 376 VTIME_SYS, 377 /* Task runs in userspace in a CPU with VTIME active: */ 378 VTIME_USER, 379 /* Task runs as guests in a CPU with VTIME active: */ 380 VTIME_GUEST, 381 }; 382 383 struct vtime { 384 seqcount_t seqcount; 385 unsigned long long starttime; 386 enum vtime_state state; 387 unsigned int cpu; 388 u64 utime; 389 u64 stime; 390 u64 gtime; 391 }; 392 393 /* 394 * Utilization clamp constraints. 395 * @UCLAMP_MIN: Minimum utilization 396 * @UCLAMP_MAX: Maximum utilization 397 * @UCLAMP_CNT: Utilization clamp constraints count 398 */ 399 enum uclamp_id { 400 UCLAMP_MIN = 0, 401 UCLAMP_MAX, 402 UCLAMP_CNT 403 }; 404 405 extern struct root_domain def_root_domain; 406 extern struct mutex sched_domains_mutex; 407 extern void sched_domains_mutex_lock(void); 408 extern void sched_domains_mutex_unlock(void); 409 410 struct sched_param { 411 int sched_priority; 412 }; 413 414 struct sched_info { 415 #ifdef CONFIG_SCHED_INFO 416 /* Cumulative counters: */ 417 418 /* # of times we have run on this CPU: */ 419 unsigned long pcount; 420 421 /* Time spent waiting on a runqueue: */ 422 unsigned long long run_delay; 423 424 /* Max time spent waiting on a runqueue: */ 425 unsigned long long max_run_delay; 426 427 /* Min time spent waiting on a runqueue: */ 428 unsigned long long min_run_delay; 429 430 /* Timestamps: */ 431 432 /* When did we last run on a CPU? */ 433 unsigned long long last_arrival; 434 435 /* When were we last queued to run? */ 436 unsigned long long last_queued; 437 438 #endif /* CONFIG_SCHED_INFO */ 439 }; 440 441 /* 442 * Integer metrics need fixed point arithmetic, e.g., sched/fair 443 * has a few: load, load_avg, util_avg, freq, and capacity. 444 * 445 * We define a basic fixed point arithmetic range, and then formalize 446 * all these metrics based on that basic range. 447 */ 448 # define SCHED_FIXEDPOINT_SHIFT 10 449 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT) 450 451 /* Increase resolution of cpu_capacity calculations */ 452 # define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT 453 # define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) 454 455 struct load_weight { 456 unsigned long weight; 457 u32 inv_weight; 458 }; 459 460 /* 461 * The load/runnable/util_avg accumulates an infinite geometric series 462 * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c). 463 * 464 * [load_avg definition] 465 * 466 * load_avg = runnable% * scale_load_down(load) 467 * 468 * [runnable_avg definition] 469 * 470 * runnable_avg = runnable% * SCHED_CAPACITY_SCALE 471 * 472 * [util_avg definition] 473 * 474 * util_avg = running% * SCHED_CAPACITY_SCALE 475 * 476 * where runnable% is the time ratio that a sched_entity is runnable and 477 * running% the time ratio that a sched_entity is running. 478 * 479 * For cfs_rq, they are the aggregated values of all runnable and blocked 480 * sched_entities. 481 * 482 * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU 483 * capacity scaling. The scaling is done through the rq_clock_pelt that is used 484 * for computing those signals (see update_rq_clock_pelt()) 485 * 486 * N.B., the above ratios (runnable% and running%) themselves are in the 487 * range of [0, 1]. To do fixed point arithmetics, we therefore scale them 488 * to as large a range as necessary. This is for example reflected by 489 * util_avg's SCHED_CAPACITY_SCALE. 490 * 491 * [Overflow issue] 492 * 493 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities 494 * with the highest load (=88761), always runnable on a single cfs_rq, 495 * and should not overflow as the number already hits PID_MAX_LIMIT. 496 * 497 * For all other cases (including 32-bit kernels), struct load_weight's 498 * weight will overflow first before we do, because: 499 * 500 * Max(load_avg) <= Max(load.weight) 501 * 502 * Then it is the load_weight's responsibility to consider overflow 503 * issues. 504 */ 505 struct sched_avg { 506 u64 last_update_time; 507 u64 load_sum; 508 u64 runnable_sum; 509 u32 util_sum; 510 u32 period_contrib; 511 unsigned long load_avg; 512 unsigned long runnable_avg; 513 unsigned long util_avg; 514 unsigned int util_est; 515 } ____cacheline_aligned; 516 517 /* 518 * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg 519 * updates. When a task is dequeued, its util_est should not be updated if its 520 * util_avg has not been updated in the meantime. 521 * This information is mapped into the MSB bit of util_est at dequeue time. 522 * Since max value of util_est for a task is 1024 (PELT util_avg for a task) 523 * it is safe to use MSB. 524 */ 525 #define UTIL_EST_WEIGHT_SHIFT 2 526 #define UTIL_AVG_UNCHANGED 0x80000000 527 528 struct sched_statistics { 529 #ifdef CONFIG_SCHEDSTATS 530 u64 wait_start; 531 u64 wait_max; 532 u64 wait_count; 533 u64 wait_sum; 534 u64 iowait_count; 535 u64 iowait_sum; 536 537 u64 sleep_start; 538 u64 sleep_max; 539 s64 sum_sleep_runtime; 540 541 u64 block_start; 542 u64 block_max; 543 s64 sum_block_runtime; 544 545 s64 exec_max; 546 u64 slice_max; 547 548 u64 nr_migrations_cold; 549 u64 nr_failed_migrations_affine; 550 u64 nr_failed_migrations_running; 551 u64 nr_failed_migrations_hot; 552 u64 nr_forced_migrations; 553 554 u64 nr_wakeups; 555 u64 nr_wakeups_sync; 556 u64 nr_wakeups_migrate; 557 u64 nr_wakeups_local; 558 u64 nr_wakeups_remote; 559 u64 nr_wakeups_affine; 560 u64 nr_wakeups_affine_attempts; 561 u64 nr_wakeups_passive; 562 u64 nr_wakeups_idle; 563 564 #ifdef CONFIG_SCHED_CORE 565 u64 core_forceidle_sum; 566 #endif 567 #endif /* CONFIG_SCHEDSTATS */ 568 } ____cacheline_aligned; 569 570 struct sched_entity { 571 /* For load-balancing: */ 572 struct load_weight load; 573 struct rb_node run_node; 574 u64 deadline; 575 u64 min_vruntime; 576 u64 min_slice; 577 578 struct list_head group_node; 579 unsigned char on_rq; 580 unsigned char sched_delayed; 581 unsigned char rel_deadline; 582 unsigned char custom_slice; 583 /* hole */ 584 585 u64 exec_start; 586 u64 sum_exec_runtime; 587 u64 prev_sum_exec_runtime; 588 u64 vruntime; 589 union { 590 /* 591 * When !@on_rq this field is vlag. 592 * When cfs_rq->curr == se (which implies @on_rq) 593 * this field is vprot. See protect_slice(). 594 */ 595 s64 vlag; 596 u64 vprot; 597 }; 598 u64 slice; 599 600 u64 nr_migrations; 601 602 #ifdef CONFIG_FAIR_GROUP_SCHED 603 int depth; 604 struct sched_entity *parent; 605 /* rq on which this entity is (to be) queued: */ 606 struct cfs_rq *cfs_rq; 607 /* rq "owned" by this entity/group: */ 608 struct cfs_rq *my_q; 609 /* cached value of my_q->h_nr_running */ 610 unsigned long runnable_weight; 611 #endif 612 613 /* 614 * Per entity load average tracking. 615 * 616 * Put into separate cache line so it does not 617 * collide with read-mostly values above. 618 */ 619 struct sched_avg avg; 620 }; 621 622 struct sched_rt_entity { 623 struct list_head run_list; 624 unsigned long timeout; 625 unsigned long watchdog_stamp; 626 unsigned int time_slice; 627 unsigned short on_rq; 628 unsigned short on_list; 629 630 struct sched_rt_entity *back; 631 #ifdef CONFIG_RT_GROUP_SCHED 632 struct sched_rt_entity *parent; 633 /* rq on which this entity is (to be) queued: */ 634 struct rt_rq *rt_rq; 635 /* rq "owned" by this entity/group: */ 636 struct rt_rq *my_q; 637 #endif 638 } __randomize_layout; 639 640 typedef bool (*dl_server_has_tasks_f)(struct sched_dl_entity *); 641 typedef struct task_struct *(*dl_server_pick_f)(struct sched_dl_entity *); 642 643 struct sched_dl_entity { 644 struct rb_node rb_node; 645 646 /* 647 * Original scheduling parameters. Copied here from sched_attr 648 * during sched_setattr(), they will remain the same until 649 * the next sched_setattr(). 650 */ 651 u64 dl_runtime; /* Maximum runtime for each instance */ 652 u64 dl_deadline; /* Relative deadline of each instance */ 653 u64 dl_period; /* Separation of two instances (period) */ 654 u64 dl_bw; /* dl_runtime / dl_period */ 655 u64 dl_density; /* dl_runtime / dl_deadline */ 656 657 /* 658 * Actual scheduling parameters. Initialized with the values above, 659 * they are continuously updated during task execution. Note that 660 * the remaining runtime could be < 0 in case we are in overrun. 661 */ 662 s64 runtime; /* Remaining runtime for this instance */ 663 u64 deadline; /* Absolute deadline for this instance */ 664 unsigned int flags; /* Specifying the scheduler behaviour */ 665 666 /* 667 * Some bool flags: 668 * 669 * @dl_throttled tells if we exhausted the runtime. If so, the 670 * task has to wait for a replenishment to be performed at the 671 * next firing of dl_timer. 672 * 673 * @dl_yielded tells if task gave up the CPU before consuming 674 * all its available runtime during the last job. 675 * 676 * @dl_non_contending tells if the task is inactive while still 677 * contributing to the active utilization. In other words, it 678 * indicates if the inactive timer has been armed and its handler 679 * has not been executed yet. This flag is useful to avoid race 680 * conditions between the inactive timer handler and the wakeup 681 * code. 682 * 683 * @dl_overrun tells if the task asked to be informed about runtime 684 * overruns. 685 * 686 * @dl_server tells if this is a server entity. 687 * 688 * @dl_defer tells if this is a deferred or regular server. For 689 * now only defer server exists. 690 * 691 * @dl_defer_armed tells if the deferrable server is waiting 692 * for the replenishment timer to activate it. 693 * 694 * @dl_server_active tells if the dlserver is active(started). 695 * dlserver is started on first cfs enqueue on an idle runqueue 696 * and is stopped when a dequeue results in 0 cfs tasks on the 697 * runqueue. In other words, dlserver is active only when cpu's 698 * runqueue has atleast one cfs task. 699 * 700 * @dl_defer_running tells if the deferrable server is actually 701 * running, skipping the defer phase. 702 */ 703 unsigned int dl_throttled : 1; 704 unsigned int dl_yielded : 1; 705 unsigned int dl_non_contending : 1; 706 unsigned int dl_overrun : 1; 707 unsigned int dl_server : 1; 708 unsigned int dl_server_active : 1; 709 unsigned int dl_defer : 1; 710 unsigned int dl_defer_armed : 1; 711 unsigned int dl_defer_running : 1; 712 713 /* 714 * Bandwidth enforcement timer. Each -deadline task has its 715 * own bandwidth to be enforced, thus we need one timer per task. 716 */ 717 struct hrtimer dl_timer; 718 719 /* 720 * Inactive timer, responsible for decreasing the active utilization 721 * at the "0-lag time". When a -deadline task blocks, it contributes 722 * to GRUB's active utilization until the "0-lag time", hence a 723 * timer is needed to decrease the active utilization at the correct 724 * time. 725 */ 726 struct hrtimer inactive_timer; 727 728 /* 729 * Bits for DL-server functionality. Also see the comment near 730 * dl_server_update(). 731 * 732 * @rq the runqueue this server is for 733 * 734 * @server_has_tasks() returns true if @server_pick return a 735 * runnable task. 736 */ 737 struct rq *rq; 738 dl_server_pick_f server_pick_task; 739 740 #ifdef CONFIG_RT_MUTEXES 741 /* 742 * Priority Inheritance. When a DEADLINE scheduling entity is boosted 743 * pi_se points to the donor, otherwise points to the dl_se it belongs 744 * to (the original one/itself). 745 */ 746 struct sched_dl_entity *pi_se; 747 #endif 748 }; 749 750 #ifdef CONFIG_UCLAMP_TASK 751 /* Number of utilization clamp buckets (shorter alias) */ 752 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT 753 754 /* 755 * Utilization clamp for a scheduling entity 756 * @value: clamp value "assigned" to a se 757 * @bucket_id: bucket index corresponding to the "assigned" value 758 * @active: the se is currently refcounted in a rq's bucket 759 * @user_defined: the requested clamp value comes from user-space 760 * 761 * The bucket_id is the index of the clamp bucket matching the clamp value 762 * which is pre-computed and stored to avoid expensive integer divisions from 763 * the fast path. 764 * 765 * The active bit is set whenever a task has got an "effective" value assigned, 766 * which can be different from the clamp value "requested" from user-space. 767 * This allows to know a task is refcounted in the rq's bucket corresponding 768 * to the "effective" bucket_id. 769 * 770 * The user_defined bit is set whenever a task has got a task-specific clamp 771 * value requested from userspace, i.e. the system defaults apply to this task 772 * just as a restriction. This allows to relax default clamps when a less 773 * restrictive task-specific value has been requested, thus allowing to 774 * implement a "nice" semantic. For example, a task running with a 20% 775 * default boost can still drop its own boosting to 0%. 776 */ 777 struct uclamp_se { 778 unsigned int value : bits_per(SCHED_CAPACITY_SCALE); 779 unsigned int bucket_id : bits_per(UCLAMP_BUCKETS); 780 unsigned int active : 1; 781 unsigned int user_defined : 1; 782 }; 783 #endif /* CONFIG_UCLAMP_TASK */ 784 785 union rcu_special { 786 struct { 787 u8 blocked; 788 u8 need_qs; 789 u8 exp_hint; /* Hint for performance. */ 790 u8 need_mb; /* Readers need smp_mb(). */ 791 } b; /* Bits. */ 792 u32 s; /* Set of bits. */ 793 }; 794 795 enum perf_event_task_context { 796 perf_invalid_context = -1, 797 perf_hw_context = 0, 798 perf_sw_context, 799 perf_nr_task_contexts, 800 }; 801 802 /* 803 * Number of contexts where an event can trigger: 804 * task, softirq, hardirq, nmi. 805 */ 806 #define PERF_NR_CONTEXTS 4 807 808 struct wake_q_node { 809 struct wake_q_node *next; 810 }; 811 812 struct kmap_ctrl { 813 #ifdef CONFIG_KMAP_LOCAL 814 int idx; 815 pte_t pteval[KM_MAX_IDX]; 816 #endif 817 }; 818 819 struct task_struct { 820 #ifdef CONFIG_THREAD_INFO_IN_TASK 821 /* 822 * For reasons of header soup (see current_thread_info()), this 823 * must be the first element of task_struct. 824 */ 825 struct thread_info thread_info; 826 #endif 827 unsigned int __state; 828 829 /* saved state for "spinlock sleepers" */ 830 unsigned int saved_state; 831 832 /* 833 * This begins the randomizable portion of task_struct. Only 834 * scheduling-critical items should be added above here. 835 */ 836 randomized_struct_fields_start 837 838 void *stack; 839 refcount_t usage; 840 /* Per task flags (PF_*), defined further below: */ 841 unsigned int flags; 842 unsigned int ptrace; 843 844 #ifdef CONFIG_MEM_ALLOC_PROFILING 845 struct alloc_tag *alloc_tag; 846 #endif 847 848 int on_cpu; 849 struct __call_single_node wake_entry; 850 unsigned int wakee_flips; 851 unsigned long wakee_flip_decay_ts; 852 struct task_struct *last_wakee; 853 854 /* 855 * recent_used_cpu is initially set as the last CPU used by a task 856 * that wakes affine another task. Waker/wakee relationships can 857 * push tasks around a CPU where each wakeup moves to the next one. 858 * Tracking a recently used CPU allows a quick search for a recently 859 * used CPU that may be idle. 860 */ 861 int recent_used_cpu; 862 int wake_cpu; 863 int on_rq; 864 865 int prio; 866 int static_prio; 867 int normal_prio; 868 unsigned int rt_priority; 869 870 struct sched_entity se; 871 struct sched_rt_entity rt; 872 struct sched_dl_entity dl; 873 struct sched_dl_entity *dl_server; 874 #ifdef CONFIG_SCHED_CLASS_EXT 875 struct sched_ext_entity scx; 876 #endif 877 const struct sched_class *sched_class; 878 879 #ifdef CONFIG_SCHED_CORE 880 struct rb_node core_node; 881 unsigned long core_cookie; 882 unsigned int core_occupation; 883 #endif 884 885 #ifdef CONFIG_CGROUP_SCHED 886 struct task_group *sched_task_group; 887 #ifdef CONFIG_CFS_BANDWIDTH 888 struct callback_head sched_throttle_work; 889 struct list_head throttle_node; 890 bool throttled; 891 #endif 892 #endif 893 894 895 #ifdef CONFIG_UCLAMP_TASK 896 /* 897 * Clamp values requested for a scheduling entity. 898 * Must be updated with task_rq_lock() held. 899 */ 900 struct uclamp_se uclamp_req[UCLAMP_CNT]; 901 /* 902 * Effective clamp values used for a scheduling entity. 903 * Must be updated with task_rq_lock() held. 904 */ 905 struct uclamp_se uclamp[UCLAMP_CNT]; 906 #endif 907 908 struct sched_statistics stats; 909 910 #ifdef CONFIG_PREEMPT_NOTIFIERS 911 /* List of struct preempt_notifier: */ 912 struct hlist_head preempt_notifiers; 913 #endif 914 915 #ifdef CONFIG_BLK_DEV_IO_TRACE 916 unsigned int btrace_seq; 917 #endif 918 919 unsigned int policy; 920 unsigned long max_allowed_capacity; 921 int nr_cpus_allowed; 922 const cpumask_t *cpus_ptr; 923 cpumask_t *user_cpus_ptr; 924 cpumask_t cpus_mask; 925 void *migration_pending; 926 unsigned short migration_disabled; 927 unsigned short migration_flags; 928 929 #ifdef CONFIG_PREEMPT_RCU 930 int rcu_read_lock_nesting; 931 union rcu_special rcu_read_unlock_special; 932 struct list_head rcu_node_entry; 933 struct rcu_node *rcu_blocked_node; 934 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 935 936 #ifdef CONFIG_TASKS_RCU 937 unsigned long rcu_tasks_nvcsw; 938 u8 rcu_tasks_holdout; 939 u8 rcu_tasks_idx; 940 int rcu_tasks_idle_cpu; 941 struct list_head rcu_tasks_holdout_list; 942 int rcu_tasks_exit_cpu; 943 struct list_head rcu_tasks_exit_list; 944 #endif /* #ifdef CONFIG_TASKS_RCU */ 945 946 #ifdef CONFIG_TASKS_TRACE_RCU 947 int trc_reader_nesting; 948 int trc_ipi_to_cpu; 949 union rcu_special trc_reader_special; 950 struct list_head trc_holdout_list; 951 struct list_head trc_blkd_node; 952 int trc_blkd_cpu; 953 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */ 954 955 struct sched_info sched_info; 956 957 struct list_head tasks; 958 struct plist_node pushable_tasks; 959 struct rb_node pushable_dl_tasks; 960 961 struct mm_struct *mm; 962 struct mm_struct *active_mm; 963 struct address_space *faults_disabled_mapping; 964 965 int exit_state; 966 int exit_code; 967 int exit_signal; 968 /* The signal sent when the parent dies: */ 969 int pdeath_signal; 970 /* JOBCTL_*, siglock protected: */ 971 unsigned long jobctl; 972 973 /* Used for emulating ABI behavior of previous Linux versions: */ 974 unsigned int personality; 975 976 /* Scheduler bits, serialized by scheduler locks: */ 977 unsigned sched_reset_on_fork:1; 978 unsigned sched_contributes_to_load:1; 979 unsigned sched_migrated:1; 980 unsigned sched_task_hot:1; 981 982 /* Force alignment to the next boundary: */ 983 unsigned :0; 984 985 /* Unserialized, strictly 'current' */ 986 987 /* 988 * This field must not be in the scheduler word above due to wakelist 989 * queueing no longer being serialized by p->on_cpu. However: 990 * 991 * p->XXX = X; ttwu() 992 * schedule() if (p->on_rq && ..) // false 993 * smp_mb__after_spinlock(); if (smp_load_acquire(&p->on_cpu) && //true 994 * deactivate_task() ttwu_queue_wakelist()) 995 * p->on_rq = 0; p->sched_remote_wakeup = Y; 996 * 997 * guarantees all stores of 'current' are visible before 998 * ->sched_remote_wakeup gets used, so it can be in this word. 999 */ 1000 unsigned sched_remote_wakeup:1; 1001 #ifdef CONFIG_RT_MUTEXES 1002 unsigned sched_rt_mutex:1; 1003 #endif 1004 1005 /* Bit to tell TOMOYO we're in execve(): */ 1006 unsigned in_execve:1; 1007 unsigned in_iowait:1; 1008 #ifndef TIF_RESTORE_SIGMASK 1009 unsigned restore_sigmask:1; 1010 #endif 1011 #ifdef CONFIG_MEMCG_V1 1012 unsigned in_user_fault:1; 1013 #endif 1014 #ifdef CONFIG_LRU_GEN 1015 /* whether the LRU algorithm may apply to this access */ 1016 unsigned in_lru_fault:1; 1017 #endif 1018 #ifdef CONFIG_COMPAT_BRK 1019 unsigned brk_randomized:1; 1020 #endif 1021 #ifdef CONFIG_CGROUPS 1022 /* disallow userland-initiated cgroup migration */ 1023 unsigned no_cgroup_migration:1; 1024 /* task is frozen/stopped (used by the cgroup freezer) */ 1025 unsigned frozen:1; 1026 #endif 1027 #ifdef CONFIG_BLK_CGROUP 1028 unsigned use_memdelay:1; 1029 #endif 1030 #ifdef CONFIG_PSI 1031 /* Stalled due to lack of memory */ 1032 unsigned in_memstall:1; 1033 #endif 1034 #ifdef CONFIG_PAGE_OWNER 1035 /* Used by page_owner=on to detect recursion in page tracking. */ 1036 unsigned in_page_owner:1; 1037 #endif 1038 #ifdef CONFIG_EVENTFD 1039 /* Recursion prevention for eventfd_signal() */ 1040 unsigned in_eventfd:1; 1041 #endif 1042 #ifdef CONFIG_ARCH_HAS_CPU_PASID 1043 unsigned pasid_activated:1; 1044 #endif 1045 #ifdef CONFIG_X86_BUS_LOCK_DETECT 1046 unsigned reported_split_lock:1; 1047 #endif 1048 #ifdef CONFIG_TASK_DELAY_ACCT 1049 /* delay due to memory thrashing */ 1050 unsigned in_thrashing:1; 1051 #endif 1052 unsigned in_nf_duplicate:1; 1053 #ifdef CONFIG_PREEMPT_RT 1054 struct netdev_xmit net_xmit; 1055 #endif 1056 unsigned long atomic_flags; /* Flags requiring atomic access. */ 1057 1058 struct restart_block restart_block; 1059 1060 pid_t pid; 1061 pid_t tgid; 1062 1063 #ifdef CONFIG_STACKPROTECTOR 1064 /* Canary value for the -fstack-protector GCC feature: */ 1065 unsigned long stack_canary; 1066 #endif 1067 /* 1068 * Pointers to the (original) parent process, youngest child, younger sibling, 1069 * older sibling, respectively. (p->father can be replaced with 1070 * p->real_parent->pid) 1071 */ 1072 1073 /* Real parent process: */ 1074 struct task_struct __rcu *real_parent; 1075 1076 /* Recipient of SIGCHLD, wait4() reports: */ 1077 struct task_struct __rcu *parent; 1078 1079 /* 1080 * Children/sibling form the list of natural children: 1081 */ 1082 struct list_head children; 1083 struct list_head sibling; 1084 struct task_struct *group_leader; 1085 1086 /* 1087 * 'ptraced' is the list of tasks this task is using ptrace() on. 1088 * 1089 * This includes both natural children and PTRACE_ATTACH targets. 1090 * 'ptrace_entry' is this task's link on the p->parent->ptraced list. 1091 */ 1092 struct list_head ptraced; 1093 struct list_head ptrace_entry; 1094 1095 /* PID/PID hash table linkage. */ 1096 struct pid *thread_pid; 1097 struct hlist_node pid_links[PIDTYPE_MAX]; 1098 struct list_head thread_node; 1099 1100 struct completion *vfork_done; 1101 1102 /* CLONE_CHILD_SETTID: */ 1103 int __user *set_child_tid; 1104 1105 /* CLONE_CHILD_CLEARTID: */ 1106 int __user *clear_child_tid; 1107 1108 /* PF_KTHREAD | PF_IO_WORKER */ 1109 void *worker_private; 1110 1111 u64 utime; 1112 u64 stime; 1113 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME 1114 u64 utimescaled; 1115 u64 stimescaled; 1116 #endif 1117 u64 gtime; 1118 struct prev_cputime prev_cputime; 1119 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1120 struct vtime vtime; 1121 #endif 1122 1123 #ifdef CONFIG_NO_HZ_FULL 1124 atomic_t tick_dep_mask; 1125 #endif 1126 /* Context switch counts: */ 1127 unsigned long nvcsw; 1128 unsigned long nivcsw; 1129 1130 /* Monotonic time in nsecs: */ 1131 u64 start_time; 1132 1133 /* Boot based time in nsecs: */ 1134 u64 start_boottime; 1135 1136 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */ 1137 unsigned long min_flt; 1138 unsigned long maj_flt; 1139 1140 /* Empty if CONFIG_POSIX_CPUTIMERS=n */ 1141 struct posix_cputimers posix_cputimers; 1142 1143 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK 1144 struct posix_cputimers_work posix_cputimers_work; 1145 #endif 1146 1147 /* Process credentials: */ 1148 1149 /* Tracer's credentials at attach: */ 1150 const struct cred __rcu *ptracer_cred; 1151 1152 /* Objective and real subjective task credentials (COW): */ 1153 const struct cred __rcu *real_cred; 1154 1155 /* Effective (overridable) subjective task credentials (COW): */ 1156 const struct cred __rcu *cred; 1157 1158 #ifdef CONFIG_KEYS 1159 /* Cached requested key. */ 1160 struct key *cached_requested_key; 1161 #endif 1162 1163 /* 1164 * executable name, excluding path. 1165 * 1166 * - normally initialized begin_new_exec() 1167 * - set it with set_task_comm() 1168 * - strscpy_pad() to ensure it is always NUL-terminated and 1169 * zero-padded 1170 * - task_lock() to ensure the operation is atomic and the name is 1171 * fully updated. 1172 */ 1173 char comm[TASK_COMM_LEN]; 1174 1175 struct nameidata *nameidata; 1176 1177 #ifdef CONFIG_SYSVIPC 1178 struct sysv_sem sysvsem; 1179 struct sysv_shm sysvshm; 1180 #endif 1181 #ifdef CONFIG_DETECT_HUNG_TASK 1182 unsigned long last_switch_count; 1183 unsigned long last_switch_time; 1184 #endif 1185 /* Filesystem information: */ 1186 struct fs_struct *fs; 1187 1188 /* Open file information: */ 1189 struct files_struct *files; 1190 1191 #ifdef CONFIG_IO_URING 1192 struct io_uring_task *io_uring; 1193 #endif 1194 1195 /* Namespaces: */ 1196 struct nsproxy *nsproxy; 1197 1198 /* Signal handlers: */ 1199 struct signal_struct *signal; 1200 struct sighand_struct __rcu *sighand; 1201 sigset_t blocked; 1202 sigset_t real_blocked; 1203 /* Restored if set_restore_sigmask() was used: */ 1204 sigset_t saved_sigmask; 1205 struct sigpending pending; 1206 unsigned long sas_ss_sp; 1207 size_t sas_ss_size; 1208 unsigned int sas_ss_flags; 1209 1210 struct callback_head *task_works; 1211 1212 #ifdef CONFIG_AUDIT 1213 #ifdef CONFIG_AUDITSYSCALL 1214 struct audit_context *audit_context; 1215 #endif 1216 kuid_t loginuid; 1217 unsigned int sessionid; 1218 #endif 1219 struct seccomp seccomp; 1220 struct syscall_user_dispatch syscall_dispatch; 1221 1222 /* Thread group tracking: */ 1223 u64 parent_exec_id; 1224 u64 self_exec_id; 1225 1226 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */ 1227 spinlock_t alloc_lock; 1228 1229 /* Protection of the PI data structures: */ 1230 raw_spinlock_t pi_lock; 1231 1232 struct wake_q_node wake_q; 1233 1234 #ifdef CONFIG_RT_MUTEXES 1235 /* PI waiters blocked on a rt_mutex held by this task: */ 1236 struct rb_root_cached pi_waiters; 1237 /* Updated under owner's pi_lock and rq lock */ 1238 struct task_struct *pi_top_task; 1239 /* Deadlock detection and priority inheritance handling: */ 1240 struct rt_mutex_waiter *pi_blocked_on; 1241 #endif 1242 1243 struct mutex *blocked_on; /* lock we're blocked on */ 1244 1245 #ifdef CONFIG_DETECT_HUNG_TASK_BLOCKER 1246 /* 1247 * Encoded lock address causing task block (lower 2 bits = type from 1248 * <linux/hung_task.h>). Accessed via hung_task_*() helpers. 1249 */ 1250 unsigned long blocker; 1251 #endif 1252 1253 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1254 int non_block_count; 1255 #endif 1256 1257 #ifdef CONFIG_TRACE_IRQFLAGS 1258 struct irqtrace_events irqtrace; 1259 unsigned int hardirq_threaded; 1260 u64 hardirq_chain_key; 1261 int softirqs_enabled; 1262 int softirq_context; 1263 int irq_config; 1264 #endif 1265 #ifdef CONFIG_PREEMPT_RT 1266 int softirq_disable_cnt; 1267 #endif 1268 1269 #ifdef CONFIG_LOCKDEP 1270 # define MAX_LOCK_DEPTH 48UL 1271 u64 curr_chain_key; 1272 int lockdep_depth; 1273 unsigned int lockdep_recursion; 1274 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1275 #endif 1276 1277 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP) 1278 unsigned int in_ubsan; 1279 #endif 1280 1281 /* Journalling filesystem info: */ 1282 void *journal_info; 1283 1284 /* Stacked block device info: */ 1285 struct bio_list *bio_list; 1286 1287 /* Stack plugging: */ 1288 struct blk_plug *plug; 1289 1290 /* VM state: */ 1291 struct reclaim_state *reclaim_state; 1292 1293 struct io_context *io_context; 1294 1295 #ifdef CONFIG_COMPACTION 1296 struct capture_control *capture_control; 1297 #endif 1298 /* Ptrace state: */ 1299 unsigned long ptrace_message; 1300 kernel_siginfo_t *last_siginfo; 1301 1302 struct task_io_accounting ioac; 1303 #ifdef CONFIG_PSI 1304 /* Pressure stall state */ 1305 unsigned int psi_flags; 1306 #endif 1307 #ifdef CONFIG_TASK_XACCT 1308 /* Accumulated RSS usage: */ 1309 u64 acct_rss_mem1; 1310 /* Accumulated virtual memory usage: */ 1311 u64 acct_vm_mem1; 1312 /* stime + utime since last update: */ 1313 u64 acct_timexpd; 1314 #endif 1315 #ifdef CONFIG_CPUSETS 1316 /* Protected by ->alloc_lock: */ 1317 nodemask_t mems_allowed; 1318 /* Sequence number to catch updates: */ 1319 seqcount_spinlock_t mems_allowed_seq; 1320 int cpuset_mem_spread_rotor; 1321 #endif 1322 #ifdef CONFIG_CGROUPS 1323 /* Control Group info protected by css_set_lock: */ 1324 struct css_set __rcu *cgroups; 1325 /* cg_list protected by css_set_lock and tsk->alloc_lock: */ 1326 struct list_head cg_list; 1327 #endif 1328 #ifdef CONFIG_X86_CPU_RESCTRL 1329 u32 closid; 1330 u32 rmid; 1331 #endif 1332 #ifdef CONFIG_FUTEX 1333 struct robust_list_head __user *robust_list; 1334 #ifdef CONFIG_COMPAT 1335 struct compat_robust_list_head __user *compat_robust_list; 1336 #endif 1337 struct list_head pi_state_list; 1338 struct futex_pi_state *pi_state_cache; 1339 struct mutex futex_exit_mutex; 1340 unsigned int futex_state; 1341 #endif 1342 #ifdef CONFIG_PERF_EVENTS 1343 u8 perf_recursion[PERF_NR_CONTEXTS]; 1344 struct perf_event_context *perf_event_ctxp; 1345 struct mutex perf_event_mutex; 1346 struct list_head perf_event_list; 1347 struct perf_ctx_data __rcu *perf_ctx_data; 1348 #endif 1349 #ifdef CONFIG_DEBUG_PREEMPT 1350 unsigned long preempt_disable_ip; 1351 #endif 1352 #ifdef CONFIG_NUMA 1353 /* Protected by alloc_lock: */ 1354 struct mempolicy *mempolicy; 1355 short il_prev; 1356 u8 il_weight; 1357 short pref_node_fork; 1358 #endif 1359 #ifdef CONFIG_NUMA_BALANCING 1360 int numa_scan_seq; 1361 unsigned int numa_scan_period; 1362 unsigned int numa_scan_period_max; 1363 int numa_preferred_nid; 1364 unsigned long numa_migrate_retry; 1365 /* Migration stamp: */ 1366 u64 node_stamp; 1367 u64 last_task_numa_placement; 1368 u64 last_sum_exec_runtime; 1369 struct callback_head numa_work; 1370 1371 /* 1372 * This pointer is only modified for current in syscall and 1373 * pagefault context (and for tasks being destroyed), so it can be read 1374 * from any of the following contexts: 1375 * - RCU read-side critical section 1376 * - current->numa_group from everywhere 1377 * - task's runqueue locked, task not running 1378 */ 1379 struct numa_group __rcu *numa_group; 1380 1381 /* 1382 * numa_faults is an array split into four regions: 1383 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer 1384 * in this precise order. 1385 * 1386 * faults_memory: Exponential decaying average of faults on a per-node 1387 * basis. Scheduling placement decisions are made based on these 1388 * counts. The values remain static for the duration of a PTE scan. 1389 * faults_cpu: Track the nodes the process was running on when a NUMA 1390 * hinting fault was incurred. 1391 * faults_memory_buffer and faults_cpu_buffer: Record faults per node 1392 * during the current scan window. When the scan completes, the counts 1393 * in faults_memory and faults_cpu decay and these values are copied. 1394 */ 1395 unsigned long *numa_faults; 1396 unsigned long total_numa_faults; 1397 1398 /* 1399 * numa_faults_locality tracks if faults recorded during the last 1400 * scan window were remote/local or failed to migrate. The task scan 1401 * period is adapted based on the locality of the faults with different 1402 * weights depending on whether they were shared or private faults 1403 */ 1404 unsigned long numa_faults_locality[3]; 1405 1406 unsigned long numa_pages_migrated; 1407 #endif /* CONFIG_NUMA_BALANCING */ 1408 1409 #ifdef CONFIG_RSEQ 1410 struct rseq __user *rseq; 1411 u32 rseq_len; 1412 u32 rseq_sig; 1413 /* 1414 * RmW on rseq_event_mask must be performed atomically 1415 * with respect to preemption. 1416 */ 1417 unsigned long rseq_event_mask; 1418 # ifdef CONFIG_DEBUG_RSEQ 1419 /* 1420 * This is a place holder to save a copy of the rseq fields for 1421 * validation of read-only fields. The struct rseq has a 1422 * variable-length array at the end, so it cannot be used 1423 * directly. Reserve a size large enough for the known fields. 1424 */ 1425 char rseq_fields[sizeof(struct rseq)]; 1426 # endif 1427 #endif 1428 1429 #ifdef CONFIG_SCHED_MM_CID 1430 int mm_cid; /* Current cid in mm */ 1431 int last_mm_cid; /* Most recent cid in mm */ 1432 int migrate_from_cpu; 1433 int mm_cid_active; /* Whether cid bitmap is active */ 1434 struct callback_head cid_work; 1435 #endif 1436 1437 struct tlbflush_unmap_batch tlb_ubc; 1438 1439 /* Cache last used pipe for splice(): */ 1440 struct pipe_inode_info *splice_pipe; 1441 1442 struct page_frag task_frag; 1443 1444 #ifdef CONFIG_TASK_DELAY_ACCT 1445 struct task_delay_info *delays; 1446 #endif 1447 1448 #ifdef CONFIG_FAULT_INJECTION 1449 int make_it_fail; 1450 unsigned int fail_nth; 1451 #endif 1452 /* 1453 * When (nr_dirtied >= nr_dirtied_pause), it's time to call 1454 * balance_dirty_pages() for a dirty throttling pause: 1455 */ 1456 int nr_dirtied; 1457 int nr_dirtied_pause; 1458 /* Start of a write-and-pause period: */ 1459 unsigned long dirty_paused_when; 1460 1461 #ifdef CONFIG_LATENCYTOP 1462 int latency_record_count; 1463 struct latency_record latency_record[LT_SAVECOUNT]; 1464 #endif 1465 /* 1466 * Time slack values; these are used to round up poll() and 1467 * select() etc timeout values. These are in nanoseconds. 1468 */ 1469 u64 timer_slack_ns; 1470 u64 default_timer_slack_ns; 1471 1472 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) 1473 unsigned int kasan_depth; 1474 #endif 1475 1476 #ifdef CONFIG_KCSAN 1477 struct kcsan_ctx kcsan_ctx; 1478 #ifdef CONFIG_TRACE_IRQFLAGS 1479 struct irqtrace_events kcsan_save_irqtrace; 1480 #endif 1481 #ifdef CONFIG_KCSAN_WEAK_MEMORY 1482 int kcsan_stack_depth; 1483 #endif 1484 #endif 1485 1486 #ifdef CONFIG_KMSAN 1487 struct kmsan_ctx kmsan_ctx; 1488 #endif 1489 1490 #if IS_ENABLED(CONFIG_KUNIT) 1491 struct kunit *kunit_test; 1492 #endif 1493 1494 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1495 /* Index of current stored address in ret_stack: */ 1496 int curr_ret_stack; 1497 int curr_ret_depth; 1498 1499 /* Stack of return addresses for return function tracing: */ 1500 unsigned long *ret_stack; 1501 1502 /* Timestamp for last schedule: */ 1503 unsigned long long ftrace_timestamp; 1504 unsigned long long ftrace_sleeptime; 1505 1506 /* 1507 * Number of functions that haven't been traced 1508 * because of depth overrun: 1509 */ 1510 atomic_t trace_overrun; 1511 1512 /* Pause tracing: */ 1513 atomic_t tracing_graph_pause; 1514 #endif 1515 1516 #ifdef CONFIG_TRACING 1517 /* Bitmask and counter of trace recursion: */ 1518 unsigned long trace_recursion; 1519 #endif /* CONFIG_TRACING */ 1520 1521 #ifdef CONFIG_KCOV 1522 /* See kernel/kcov.c for more details. */ 1523 1524 /* Coverage collection mode enabled for this task (0 if disabled): */ 1525 unsigned int kcov_mode; 1526 1527 /* Size of the kcov_area: */ 1528 unsigned int kcov_size; 1529 1530 /* Buffer for coverage collection: */ 1531 void *kcov_area; 1532 1533 /* KCOV descriptor wired with this task or NULL: */ 1534 struct kcov *kcov; 1535 1536 /* KCOV common handle for remote coverage collection: */ 1537 u64 kcov_handle; 1538 1539 /* KCOV sequence number: */ 1540 int kcov_sequence; 1541 1542 /* Collect coverage from softirq context: */ 1543 unsigned int kcov_softirq; 1544 #endif 1545 1546 #ifdef CONFIG_MEMCG_V1 1547 struct mem_cgroup *memcg_in_oom; 1548 #endif 1549 1550 #ifdef CONFIG_MEMCG 1551 /* Number of pages to reclaim on returning to userland: */ 1552 unsigned int memcg_nr_pages_over_high; 1553 1554 /* Used by memcontrol for targeted memcg charge: */ 1555 struct mem_cgroup *active_memcg; 1556 1557 /* Cache for current->cgroups->memcg->objcg lookups: */ 1558 struct obj_cgroup *objcg; 1559 #endif 1560 1561 #ifdef CONFIG_BLK_CGROUP 1562 struct gendisk *throttle_disk; 1563 #endif 1564 1565 #ifdef CONFIG_UPROBES 1566 struct uprobe_task *utask; 1567 #endif 1568 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1569 unsigned int sequential_io; 1570 unsigned int sequential_io_avg; 1571 #endif 1572 struct kmap_ctrl kmap_ctrl; 1573 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1574 unsigned long task_state_change; 1575 # ifdef CONFIG_PREEMPT_RT 1576 unsigned long saved_state_change; 1577 # endif 1578 #endif 1579 struct rcu_head rcu; 1580 refcount_t rcu_users; 1581 int pagefault_disabled; 1582 #ifdef CONFIG_MMU 1583 struct task_struct *oom_reaper_list; 1584 struct timer_list oom_reaper_timer; 1585 #endif 1586 #ifdef CONFIG_VMAP_STACK 1587 struct vm_struct *stack_vm_area; 1588 #endif 1589 #ifdef CONFIG_THREAD_INFO_IN_TASK 1590 /* A live task holds one reference: */ 1591 refcount_t stack_refcount; 1592 #endif 1593 #ifdef CONFIG_LIVEPATCH 1594 int patch_state; 1595 #endif 1596 #ifdef CONFIG_SECURITY 1597 /* Used by LSM modules for access restriction: */ 1598 void *security; 1599 #endif 1600 #ifdef CONFIG_BPF_SYSCALL 1601 /* Used by BPF task local storage */ 1602 struct bpf_local_storage __rcu *bpf_storage; 1603 /* Used for BPF run context */ 1604 struct bpf_run_ctx *bpf_ctx; 1605 #endif 1606 /* Used by BPF for per-TASK xdp storage */ 1607 struct bpf_net_context *bpf_net_context; 1608 1609 #ifdef CONFIG_KSTACK_ERASE 1610 unsigned long lowest_stack; 1611 #endif 1612 #ifdef CONFIG_KSTACK_ERASE_METRICS 1613 unsigned long prev_lowest_stack; 1614 #endif 1615 1616 #ifdef CONFIG_X86_MCE 1617 void __user *mce_vaddr; 1618 __u64 mce_kflags; 1619 u64 mce_addr; 1620 __u64 mce_ripv : 1, 1621 mce_whole_page : 1, 1622 __mce_reserved : 62; 1623 struct callback_head mce_kill_me; 1624 int mce_count; 1625 #endif 1626 1627 #ifdef CONFIG_KRETPROBES 1628 struct llist_head kretprobe_instances; 1629 #endif 1630 #ifdef CONFIG_RETHOOK 1631 struct llist_head rethooks; 1632 #endif 1633 1634 #ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH 1635 /* 1636 * If L1D flush is supported on mm context switch 1637 * then we use this callback head to queue kill work 1638 * to kill tasks that are not running on SMT disabled 1639 * cores 1640 */ 1641 struct callback_head l1d_flush_kill; 1642 #endif 1643 1644 #ifdef CONFIG_RV 1645 /* 1646 * Per-task RV monitor, fixed in CONFIG_RV_PER_TASK_MONITORS. 1647 * If memory becomes a concern, we can think about a dynamic method. 1648 */ 1649 union rv_task_monitor rv[CONFIG_RV_PER_TASK_MONITORS]; 1650 #endif 1651 1652 #ifdef CONFIG_USER_EVENTS 1653 struct user_event_mm *user_event_mm; 1654 #endif 1655 1656 #ifdef CONFIG_UNWIND_USER 1657 struct unwind_task_info unwind_info; 1658 #endif 1659 1660 /* CPU-specific state of this task: */ 1661 struct thread_struct thread; 1662 1663 /* 1664 * New fields for task_struct should be added above here, so that 1665 * they are included in the randomized portion of task_struct. 1666 */ 1667 randomized_struct_fields_end 1668 } __attribute__ ((aligned (64))); 1669 1670 #ifdef CONFIG_SCHED_PROXY_EXEC 1671 DECLARE_STATIC_KEY_TRUE(__sched_proxy_exec); 1672 static inline bool sched_proxy_exec(void) 1673 { 1674 return static_branch_likely(&__sched_proxy_exec); 1675 } 1676 #else 1677 static inline bool sched_proxy_exec(void) 1678 { 1679 return false; 1680 } 1681 #endif 1682 1683 #define TASK_REPORT_IDLE (TASK_REPORT + 1) 1684 #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1) 1685 1686 static inline unsigned int __task_state_index(unsigned int tsk_state, 1687 unsigned int tsk_exit_state) 1688 { 1689 unsigned int state = (tsk_state | tsk_exit_state) & TASK_REPORT; 1690 1691 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX); 1692 1693 if ((tsk_state & TASK_IDLE) == TASK_IDLE) 1694 state = TASK_REPORT_IDLE; 1695 1696 /* 1697 * We're lying here, but rather than expose a completely new task state 1698 * to userspace, we can make this appear as if the task has gone through 1699 * a regular rt_mutex_lock() call. 1700 * Report frozen tasks as uninterruptible. 1701 */ 1702 if ((tsk_state & TASK_RTLOCK_WAIT) || (tsk_state & TASK_FROZEN)) 1703 state = TASK_UNINTERRUPTIBLE; 1704 1705 return fls(state); 1706 } 1707 1708 static inline unsigned int task_state_index(struct task_struct *tsk) 1709 { 1710 return __task_state_index(READ_ONCE(tsk->__state), tsk->exit_state); 1711 } 1712 1713 static inline char task_index_to_char(unsigned int state) 1714 { 1715 static const char state_char[] = "RSDTtXZPI"; 1716 1717 BUILD_BUG_ON(TASK_REPORT_MAX * 2 != 1 << (sizeof(state_char) - 1)); 1718 1719 return state_char[state]; 1720 } 1721 1722 static inline char task_state_to_char(struct task_struct *tsk) 1723 { 1724 return task_index_to_char(task_state_index(tsk)); 1725 } 1726 1727 extern struct pid *cad_pid; 1728 1729 /* 1730 * Per process flags 1731 */ 1732 #define PF_VCPU 0x00000001 /* I'm a virtual CPU */ 1733 #define PF_IDLE 0x00000002 /* I am an IDLE thread */ 1734 #define PF_EXITING 0x00000004 /* Getting shut down */ 1735 #define PF_POSTCOREDUMP 0x00000008 /* Coredumps should ignore this task */ 1736 #define PF_IO_WORKER 0x00000010 /* Task is an IO worker */ 1737 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 1738 #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */ 1739 #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */ 1740 #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */ 1741 #define PF_DUMPCORE 0x00000200 /* Dumped core */ 1742 #define PF_SIGNALED 0x00000400 /* Killed by a signal */ 1743 #define PF_MEMALLOC 0x00000800 /* Allocating memory to free memory. See memalloc_noreclaim_save() */ 1744 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */ 1745 #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */ 1746 #define PF_USER_WORKER 0x00004000 /* Kernel thread cloned from userspace thread */ 1747 #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */ 1748 #define PF_KCOMPACTD 0x00010000 /* I am kcompactd */ 1749 #define PF_KSWAPD 0x00020000 /* I am kswapd */ 1750 #define PF_MEMALLOC_NOFS 0x00040000 /* All allocations inherit GFP_NOFS. See memalloc_nfs_save() */ 1751 #define PF_MEMALLOC_NOIO 0x00080000 /* All allocations inherit GFP_NOIO. See memalloc_noio_save() */ 1752 #define PF_LOCAL_THROTTLE 0x00100000 /* Throttle writes only against the bdi I write to, 1753 * I am cleaning dirty pages from some other bdi. */ 1754 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 1755 #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */ 1756 #define PF__HOLE__00800000 0x00800000 1757 #define PF__HOLE__01000000 0x01000000 1758 #define PF__HOLE__02000000 0x02000000 1759 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */ 1760 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 1761 #define PF_MEMALLOC_PIN 0x10000000 /* Allocations constrained to zones which allow long term pinning. 1762 * See memalloc_pin_save() */ 1763 #define PF_BLOCK_TS 0x20000000 /* plug has ts that needs updating */ 1764 #define PF__HOLE__40000000 0x40000000 1765 #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */ 1766 1767 /* 1768 * Only the _current_ task can read/write to tsk->flags, but other 1769 * tasks can access tsk->flags in readonly mode for example 1770 * with tsk_used_math (like during threaded core dumping). 1771 * There is however an exception to this rule during ptrace 1772 * or during fork: the ptracer task is allowed to write to the 1773 * child->flags of its traced child (same goes for fork, the parent 1774 * can write to the child->flags), because we're guaranteed the 1775 * child is not running and in turn not changing child->flags 1776 * at the same time the parent does it. 1777 */ 1778 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1779 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1780 #define clear_used_math() clear_stopped_child_used_math(current) 1781 #define set_used_math() set_stopped_child_used_math(current) 1782 1783 #define conditional_stopped_child_used_math(condition, child) \ 1784 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1785 1786 #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current) 1787 1788 #define copy_to_stopped_child_used_math(child) \ 1789 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1790 1791 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1792 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1793 #define used_math() tsk_used_math(current) 1794 1795 static __always_inline bool is_percpu_thread(void) 1796 { 1797 return (current->flags & PF_NO_SETAFFINITY) && 1798 (current->nr_cpus_allowed == 1); 1799 } 1800 1801 /* Per-process atomic flags. */ 1802 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */ 1803 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */ 1804 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */ 1805 #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */ 1806 #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/ 1807 #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */ 1808 #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */ 1809 #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */ 1810 1811 #define TASK_PFA_TEST(name, func) \ 1812 static inline bool task_##func(struct task_struct *p) \ 1813 { return test_bit(PFA_##name, &p->atomic_flags); } 1814 1815 #define TASK_PFA_SET(name, func) \ 1816 static inline void task_set_##func(struct task_struct *p) \ 1817 { set_bit(PFA_##name, &p->atomic_flags); } 1818 1819 #define TASK_PFA_CLEAR(name, func) \ 1820 static inline void task_clear_##func(struct task_struct *p) \ 1821 { clear_bit(PFA_##name, &p->atomic_flags); } 1822 1823 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs) 1824 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs) 1825 1826 TASK_PFA_TEST(SPREAD_PAGE, spread_page) 1827 TASK_PFA_SET(SPREAD_PAGE, spread_page) 1828 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page) 1829 1830 TASK_PFA_TEST(SPREAD_SLAB, spread_slab) 1831 TASK_PFA_SET(SPREAD_SLAB, spread_slab) 1832 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab) 1833 1834 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable) 1835 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable) 1836 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable) 1837 1838 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1839 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1840 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1841 1842 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1843 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1844 1845 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable) 1846 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable) 1847 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable) 1848 1849 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1850 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1851 1852 static inline void 1853 current_restore_flags(unsigned long orig_flags, unsigned long flags) 1854 { 1855 current->flags &= ~flags; 1856 current->flags |= orig_flags & flags; 1857 } 1858 1859 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 1860 extern int task_can_attach(struct task_struct *p); 1861 extern int dl_bw_alloc(int cpu, u64 dl_bw); 1862 extern void dl_bw_free(int cpu, u64 dl_bw); 1863 1864 /* do_set_cpus_allowed() - consider using set_cpus_allowed_ptr() instead */ 1865 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask); 1866 1867 /** 1868 * set_cpus_allowed_ptr - set CPU affinity mask of a task 1869 * @p: the task 1870 * @new_mask: CPU affinity mask 1871 * 1872 * Return: zero if successful, or a negative error code 1873 */ 1874 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask); 1875 extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node); 1876 extern void release_user_cpus_ptr(struct task_struct *p); 1877 extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask); 1878 extern void force_compatible_cpus_allowed_ptr(struct task_struct *p); 1879 extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p); 1880 1881 extern int yield_to(struct task_struct *p, bool preempt); 1882 extern void set_user_nice(struct task_struct *p, long nice); 1883 extern int task_prio(const struct task_struct *p); 1884 1885 /** 1886 * task_nice - return the nice value of a given task. 1887 * @p: the task in question. 1888 * 1889 * Return: The nice value [ -20 ... 0 ... 19 ]. 1890 */ 1891 static inline int task_nice(const struct task_struct *p) 1892 { 1893 return PRIO_TO_NICE((p)->static_prio); 1894 } 1895 1896 extern int can_nice(const struct task_struct *p, const int nice); 1897 extern int task_curr(const struct task_struct *p); 1898 extern int idle_cpu(int cpu); 1899 extern int available_idle_cpu(int cpu); 1900 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *); 1901 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *); 1902 extern void sched_set_fifo(struct task_struct *p); 1903 extern void sched_set_fifo_low(struct task_struct *p); 1904 extern void sched_set_normal(struct task_struct *p, int nice); 1905 extern int sched_setattr(struct task_struct *, const struct sched_attr *); 1906 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *); 1907 extern struct task_struct *idle_task(int cpu); 1908 1909 /** 1910 * is_idle_task - is the specified task an idle task? 1911 * @p: the task in question. 1912 * 1913 * Return: 1 if @p is an idle task. 0 otherwise. 1914 */ 1915 static __always_inline bool is_idle_task(const struct task_struct *p) 1916 { 1917 return !!(p->flags & PF_IDLE); 1918 } 1919 1920 extern struct task_struct *curr_task(int cpu); 1921 extern void ia64_set_curr_task(int cpu, struct task_struct *p); 1922 1923 void yield(void); 1924 1925 union thread_union { 1926 struct task_struct task; 1927 #ifndef CONFIG_THREAD_INFO_IN_TASK 1928 struct thread_info thread_info; 1929 #endif 1930 unsigned long stack[THREAD_SIZE/sizeof(long)]; 1931 }; 1932 1933 #ifndef CONFIG_THREAD_INFO_IN_TASK 1934 extern struct thread_info init_thread_info; 1935 #endif 1936 1937 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)]; 1938 1939 #ifdef CONFIG_THREAD_INFO_IN_TASK 1940 # define task_thread_info(task) (&(task)->thread_info) 1941 #else 1942 # define task_thread_info(task) ((struct thread_info *)(task)->stack) 1943 #endif 1944 1945 /* 1946 * find a task by one of its numerical ids 1947 * 1948 * find_task_by_pid_ns(): 1949 * finds a task by its pid in the specified namespace 1950 * find_task_by_vpid(): 1951 * finds a task by its virtual pid 1952 * 1953 * see also find_vpid() etc in include/linux/pid.h 1954 */ 1955 1956 extern struct task_struct *find_task_by_vpid(pid_t nr); 1957 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns); 1958 1959 /* 1960 * find a task by its virtual pid and get the task struct 1961 */ 1962 extern struct task_struct *find_get_task_by_vpid(pid_t nr); 1963 1964 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 1965 extern int wake_up_process(struct task_struct *tsk); 1966 extern void wake_up_new_task(struct task_struct *tsk); 1967 1968 extern void kick_process(struct task_struct *tsk); 1969 1970 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); 1971 #define set_task_comm(tsk, from) ({ \ 1972 BUILD_BUG_ON(sizeof(from) != TASK_COMM_LEN); \ 1973 __set_task_comm(tsk, from, false); \ 1974 }) 1975 1976 /* 1977 * - Why not use task_lock()? 1978 * User space can randomly change their names anyway, so locking for readers 1979 * doesn't make sense. For writers, locking is probably necessary, as a race 1980 * condition could lead to long-term mixed results. 1981 * The strscpy_pad() in __set_task_comm() can ensure that the task comm is 1982 * always NUL-terminated and zero-padded. Therefore the race condition between 1983 * reader and writer is not an issue. 1984 * 1985 * - BUILD_BUG_ON() can help prevent the buf from being truncated. 1986 * Since the callers don't perform any return value checks, this safeguard is 1987 * necessary. 1988 */ 1989 #define get_task_comm(buf, tsk) ({ \ 1990 BUILD_BUG_ON(sizeof(buf) < TASK_COMM_LEN); \ 1991 strscpy_pad(buf, (tsk)->comm); \ 1992 buf; \ 1993 }) 1994 1995 static __always_inline void scheduler_ipi(void) 1996 { 1997 /* 1998 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting 1999 * TIF_NEED_RESCHED remotely (for the first time) will also send 2000 * this IPI. 2001 */ 2002 preempt_fold_need_resched(); 2003 } 2004 2005 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state); 2006 2007 /* 2008 * Set thread flags in other task's structures. 2009 * See asm/thread_info.h for TIF_xxxx flags available: 2010 */ 2011 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 2012 { 2013 set_ti_thread_flag(task_thread_info(tsk), flag); 2014 } 2015 2016 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2017 { 2018 clear_ti_thread_flag(task_thread_info(tsk), flag); 2019 } 2020 2021 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag, 2022 bool value) 2023 { 2024 update_ti_thread_flag(task_thread_info(tsk), flag, value); 2025 } 2026 2027 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 2028 { 2029 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 2030 } 2031 2032 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2033 { 2034 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 2035 } 2036 2037 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 2038 { 2039 return test_ti_thread_flag(task_thread_info(tsk), flag); 2040 } 2041 2042 static inline void set_tsk_need_resched(struct task_struct *tsk) 2043 { 2044 if (tracepoint_enabled(sched_set_need_resched_tp) && 2045 !test_tsk_thread_flag(tsk, TIF_NEED_RESCHED)) 2046 __trace_set_need_resched(tsk, TIF_NEED_RESCHED); 2047 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2048 } 2049 2050 static inline void clear_tsk_need_resched(struct task_struct *tsk) 2051 { 2052 atomic_long_andnot(_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY, 2053 (atomic_long_t *)&task_thread_info(tsk)->flags); 2054 } 2055 2056 static inline int test_tsk_need_resched(struct task_struct *tsk) 2057 { 2058 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 2059 } 2060 2061 /* 2062 * cond_resched() and cond_resched_lock(): latency reduction via 2063 * explicit rescheduling in places that are safe. The return 2064 * value indicates whether a reschedule was done in fact. 2065 * cond_resched_lock() will drop the spinlock before scheduling, 2066 */ 2067 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) 2068 extern int __cond_resched(void); 2069 2070 #if defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL) 2071 2072 DECLARE_STATIC_CALL(cond_resched, __cond_resched); 2073 2074 static __always_inline int _cond_resched(void) 2075 { 2076 return static_call_mod(cond_resched)(); 2077 } 2078 2079 #elif defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY) 2080 2081 extern int dynamic_cond_resched(void); 2082 2083 static __always_inline int _cond_resched(void) 2084 { 2085 return dynamic_cond_resched(); 2086 } 2087 2088 #else /* !CONFIG_PREEMPTION */ 2089 2090 static inline int _cond_resched(void) 2091 { 2092 return __cond_resched(); 2093 } 2094 2095 #endif /* PREEMPT_DYNAMIC && CONFIG_HAVE_PREEMPT_DYNAMIC_CALL */ 2096 2097 #else /* CONFIG_PREEMPTION && !CONFIG_PREEMPT_DYNAMIC */ 2098 2099 static inline int _cond_resched(void) 2100 { 2101 return 0; 2102 } 2103 2104 #endif /* !CONFIG_PREEMPTION || CONFIG_PREEMPT_DYNAMIC */ 2105 2106 #define cond_resched() ({ \ 2107 __might_resched(__FILE__, __LINE__, 0); \ 2108 _cond_resched(); \ 2109 }) 2110 2111 extern int __cond_resched_lock(spinlock_t *lock); 2112 extern int __cond_resched_rwlock_read(rwlock_t *lock); 2113 extern int __cond_resched_rwlock_write(rwlock_t *lock); 2114 2115 #define MIGHT_RESCHED_RCU_SHIFT 8 2116 #define MIGHT_RESCHED_PREEMPT_MASK ((1U << MIGHT_RESCHED_RCU_SHIFT) - 1) 2117 2118 #ifndef CONFIG_PREEMPT_RT 2119 /* 2120 * Non RT kernels have an elevated preempt count due to the held lock, 2121 * but are not allowed to be inside a RCU read side critical section 2122 */ 2123 # define PREEMPT_LOCK_RESCHED_OFFSETS PREEMPT_LOCK_OFFSET 2124 #else 2125 /* 2126 * spin/rw_lock() on RT implies rcu_read_lock(). The might_sleep() check in 2127 * cond_resched*lock() has to take that into account because it checks for 2128 * preempt_count() and rcu_preempt_depth(). 2129 */ 2130 # define PREEMPT_LOCK_RESCHED_OFFSETS \ 2131 (PREEMPT_LOCK_OFFSET + (1U << MIGHT_RESCHED_RCU_SHIFT)) 2132 #endif 2133 2134 #define cond_resched_lock(lock) ({ \ 2135 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ 2136 __cond_resched_lock(lock); \ 2137 }) 2138 2139 #define cond_resched_rwlock_read(lock) ({ \ 2140 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ 2141 __cond_resched_rwlock_read(lock); \ 2142 }) 2143 2144 #define cond_resched_rwlock_write(lock) ({ \ 2145 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ 2146 __cond_resched_rwlock_write(lock); \ 2147 }) 2148 2149 #ifndef CONFIG_PREEMPT_RT 2150 static inline struct mutex *__get_task_blocked_on(struct task_struct *p) 2151 { 2152 struct mutex *m = p->blocked_on; 2153 2154 if (m) 2155 lockdep_assert_held_once(&m->wait_lock); 2156 return m; 2157 } 2158 2159 static inline void __set_task_blocked_on(struct task_struct *p, struct mutex *m) 2160 { 2161 struct mutex *blocked_on = READ_ONCE(p->blocked_on); 2162 2163 WARN_ON_ONCE(!m); 2164 /* The task should only be setting itself as blocked */ 2165 WARN_ON_ONCE(p != current); 2166 /* Currently we serialize blocked_on under the mutex::wait_lock */ 2167 lockdep_assert_held_once(&m->wait_lock); 2168 /* 2169 * Check ensure we don't overwrite existing mutex value 2170 * with a different mutex. Note, setting it to the same 2171 * lock repeatedly is ok. 2172 */ 2173 WARN_ON_ONCE(blocked_on && blocked_on != m); 2174 WRITE_ONCE(p->blocked_on, m); 2175 } 2176 2177 static inline void set_task_blocked_on(struct task_struct *p, struct mutex *m) 2178 { 2179 guard(raw_spinlock_irqsave)(&m->wait_lock); 2180 __set_task_blocked_on(p, m); 2181 } 2182 2183 static inline void __clear_task_blocked_on(struct task_struct *p, struct mutex *m) 2184 { 2185 if (m) { 2186 struct mutex *blocked_on = READ_ONCE(p->blocked_on); 2187 2188 /* Currently we serialize blocked_on under the mutex::wait_lock */ 2189 lockdep_assert_held_once(&m->wait_lock); 2190 /* 2191 * There may be cases where we re-clear already cleared 2192 * blocked_on relationships, but make sure we are not 2193 * clearing the relationship with a different lock. 2194 */ 2195 WARN_ON_ONCE(blocked_on && blocked_on != m); 2196 } 2197 WRITE_ONCE(p->blocked_on, NULL); 2198 } 2199 2200 static inline void clear_task_blocked_on(struct task_struct *p, struct mutex *m) 2201 { 2202 guard(raw_spinlock_irqsave)(&m->wait_lock); 2203 __clear_task_blocked_on(p, m); 2204 } 2205 #else 2206 static inline void __clear_task_blocked_on(struct task_struct *p, struct rt_mutex *m) 2207 { 2208 } 2209 2210 static inline void clear_task_blocked_on(struct task_struct *p, struct rt_mutex *m) 2211 { 2212 } 2213 #endif /* !CONFIG_PREEMPT_RT */ 2214 2215 static __always_inline bool need_resched(void) 2216 { 2217 return unlikely(tif_need_resched()); 2218 } 2219 2220 /* 2221 * Wrappers for p->thread_info->cpu access. No-op on UP. 2222 */ 2223 #ifdef CONFIG_SMP 2224 2225 static inline unsigned int task_cpu(const struct task_struct *p) 2226 { 2227 return READ_ONCE(task_thread_info(p)->cpu); 2228 } 2229 2230 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 2231 2232 #else 2233 2234 static inline unsigned int task_cpu(const struct task_struct *p) 2235 { 2236 return 0; 2237 } 2238 2239 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 2240 { 2241 } 2242 2243 #endif /* CONFIG_SMP */ 2244 2245 static inline bool task_is_runnable(struct task_struct *p) 2246 { 2247 return p->on_rq && !p->se.sched_delayed; 2248 } 2249 2250 extern bool sched_task_on_rq(struct task_struct *p); 2251 extern unsigned long get_wchan(struct task_struct *p); 2252 extern struct task_struct *cpu_curr_snapshot(int cpu); 2253 2254 /* 2255 * In order to reduce various lock holder preemption latencies provide an 2256 * interface to see if a vCPU is currently running or not. 2257 * 2258 * This allows us to terminate optimistic spin loops and block, analogous to 2259 * the native optimistic spin heuristic of testing if the lock owner task is 2260 * running or not. 2261 */ 2262 #ifndef vcpu_is_preempted 2263 static inline bool vcpu_is_preempted(int cpu) 2264 { 2265 return false; 2266 } 2267 #endif 2268 2269 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 2270 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 2271 2272 #ifndef TASK_SIZE_OF 2273 #define TASK_SIZE_OF(tsk) TASK_SIZE 2274 #endif 2275 2276 static inline bool owner_on_cpu(struct task_struct *owner) 2277 { 2278 /* 2279 * As lock holder preemption issue, we both skip spinning if 2280 * task is not on cpu or its cpu is preempted 2281 */ 2282 return READ_ONCE(owner->on_cpu) && !vcpu_is_preempted(task_cpu(owner)); 2283 } 2284 2285 /* Returns effective CPU energy utilization, as seen by the scheduler */ 2286 unsigned long sched_cpu_util(int cpu); 2287 2288 #ifdef CONFIG_SCHED_CORE 2289 extern void sched_core_free(struct task_struct *tsk); 2290 extern void sched_core_fork(struct task_struct *p); 2291 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type, 2292 unsigned long uaddr); 2293 extern int sched_core_idle_cpu(int cpu); 2294 #else 2295 static inline void sched_core_free(struct task_struct *tsk) { } 2296 static inline void sched_core_fork(struct task_struct *p) { } 2297 static inline int sched_core_idle_cpu(int cpu) { return idle_cpu(cpu); } 2298 #endif 2299 2300 extern void sched_set_stop_task(int cpu, struct task_struct *stop); 2301 2302 #ifdef CONFIG_MEM_ALLOC_PROFILING 2303 static __always_inline struct alloc_tag *alloc_tag_save(struct alloc_tag *tag) 2304 { 2305 swap(current->alloc_tag, tag); 2306 return tag; 2307 } 2308 2309 static __always_inline void alloc_tag_restore(struct alloc_tag *tag, struct alloc_tag *old) 2310 { 2311 #ifdef CONFIG_MEM_ALLOC_PROFILING_DEBUG 2312 WARN(current->alloc_tag != tag, "current->alloc_tag was changed:\n"); 2313 #endif 2314 current->alloc_tag = old; 2315 } 2316 #else 2317 #define alloc_tag_save(_tag) NULL 2318 #define alloc_tag_restore(_tag, _old) do {} while (0) 2319 #endif 2320 2321 #ifndef MODULE 2322 #ifndef COMPILE_OFFSETS 2323 2324 extern void ___migrate_enable(void); 2325 2326 struct rq; 2327 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); 2328 2329 /* 2330 * The "struct rq" is not available here, so we can't access the 2331 * "runqueues" with this_cpu_ptr(), as the compilation will fail in 2332 * this_cpu_ptr() -> raw_cpu_ptr() -> __verify_pcpu_ptr(): 2333 * typeof((ptr) + 0) 2334 * 2335 * So use arch_raw_cpu_ptr()/PERCPU_PTR() directly here. 2336 */ 2337 #ifdef CONFIG_SMP 2338 #define this_rq_raw() arch_raw_cpu_ptr(&runqueues) 2339 #else 2340 #define this_rq_raw() PERCPU_PTR(&runqueues) 2341 #endif 2342 #define this_rq_pinned() (*(unsigned int *)((void *)this_rq_raw() + RQ_nr_pinned)) 2343 2344 static inline void __migrate_enable(void) 2345 { 2346 struct task_struct *p = current; 2347 2348 #ifdef CONFIG_DEBUG_PREEMPT 2349 /* 2350 * Check both overflow from migrate_disable() and superfluous 2351 * migrate_enable(). 2352 */ 2353 if (WARN_ON_ONCE((s16)p->migration_disabled <= 0)) 2354 return; 2355 #endif 2356 2357 if (p->migration_disabled > 1) { 2358 p->migration_disabled--; 2359 return; 2360 } 2361 2362 /* 2363 * Ensure stop_task runs either before or after this, and that 2364 * __set_cpus_allowed_ptr(SCA_MIGRATE_ENABLE) doesn't schedule(). 2365 */ 2366 guard(preempt)(); 2367 if (unlikely(p->cpus_ptr != &p->cpus_mask)) 2368 ___migrate_enable(); 2369 /* 2370 * Mustn't clear migration_disabled() until cpus_ptr points back at the 2371 * regular cpus_mask, otherwise things that race (eg. 2372 * select_fallback_rq) get confused. 2373 */ 2374 barrier(); 2375 p->migration_disabled = 0; 2376 this_rq_pinned()--; 2377 } 2378 2379 static inline void __migrate_disable(void) 2380 { 2381 struct task_struct *p = current; 2382 2383 if (p->migration_disabled) { 2384 #ifdef CONFIG_DEBUG_PREEMPT 2385 /* 2386 *Warn about overflow half-way through the range. 2387 */ 2388 WARN_ON_ONCE((s16)p->migration_disabled < 0); 2389 #endif 2390 p->migration_disabled++; 2391 return; 2392 } 2393 2394 guard(preempt)(); 2395 this_rq_pinned()++; 2396 p->migration_disabled = 1; 2397 } 2398 #else /* !COMPILE_OFFSETS */ 2399 static inline void __migrate_disable(void) { } 2400 static inline void __migrate_enable(void) { } 2401 #endif /* !COMPILE_OFFSETS */ 2402 2403 /* 2404 * So that it is possible to not export the runqueues variable, define and 2405 * export migrate_enable/migrate_disable in kernel/sched/core.c too, and use 2406 * them for the modules. The macro "INSTANTIATE_EXPORTED_MIGRATE_DISABLE" will 2407 * be defined in kernel/sched/core.c. 2408 */ 2409 #ifndef INSTANTIATE_EXPORTED_MIGRATE_DISABLE 2410 static inline void migrate_disable(void) 2411 { 2412 __migrate_disable(); 2413 } 2414 2415 static inline void migrate_enable(void) 2416 { 2417 __migrate_enable(); 2418 } 2419 #else /* INSTANTIATE_EXPORTED_MIGRATE_DISABLE */ 2420 extern void migrate_disable(void); 2421 extern void migrate_enable(void); 2422 #endif /* INSTANTIATE_EXPORTED_MIGRATE_DISABLE */ 2423 2424 #else /* MODULE */ 2425 extern void migrate_disable(void); 2426 extern void migrate_enable(void); 2427 #endif /* MODULE */ 2428 2429 DEFINE_LOCK_GUARD_0(migrate, migrate_disable(), migrate_enable()) 2430 2431 #endif 2432