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 <linux/rseq_types.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 #include <linux/time64.h> 53 #ifndef COMPILE_OFFSETS 54 #include <generated/rq-offsets.h> 55 #endif 56 57 /* task_struct member predeclarations (sorted alphabetically): */ 58 struct audit_context; 59 struct bio_list; 60 struct blk_plug; 61 struct bpf_local_storage; 62 struct bpf_run_ctx; 63 struct bpf_net_context; 64 struct capture_control; 65 struct cfs_rq; 66 struct fs_struct; 67 struct futex_pi_state; 68 struct io_context; 69 struct io_uring_task; 70 struct mempolicy; 71 struct nameidata; 72 struct nsproxy; 73 struct perf_event_context; 74 struct perf_ctx_data; 75 struct pid_namespace; 76 struct pipe_inode_info; 77 struct rcu_node; 78 struct reclaim_state; 79 struct robust_list_head; 80 struct root_domain; 81 struct rq; 82 struct sched_attr; 83 struct sched_dl_entity; 84 struct seq_file; 85 struct sighand_struct; 86 struct signal_struct; 87 struct task_delay_info; 88 struct task_group; 89 struct task_struct; 90 struct timespec64; 91 struct user_event_mm; 92 93 #include <linux/sched/ext.h> 94 95 /* 96 * Task state bitmask. NOTE! These bits are also 97 * encoded in fs/proc/array.c: get_task_state(). 98 * 99 * We have two separate sets of flags: task->__state 100 * is about runnability, while task->exit_state are 101 * about the task exiting. Confusing, but this way 102 * modifying one set can't modify the other one by 103 * mistake. 104 */ 105 106 /* Used in tsk->__state: */ 107 #define TASK_RUNNING 0x00000000 108 #define TASK_INTERRUPTIBLE 0x00000001 109 #define TASK_UNINTERRUPTIBLE 0x00000002 110 #define __TASK_STOPPED 0x00000004 111 #define __TASK_TRACED 0x00000008 112 /* Used in tsk->exit_state: */ 113 #define EXIT_DEAD 0x00000010 114 #define EXIT_ZOMBIE 0x00000020 115 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD) 116 /* Used in tsk->__state again: */ 117 #define TASK_PARKED 0x00000040 118 #define TASK_DEAD 0x00000080 119 #define TASK_WAKEKILL 0x00000100 120 #define TASK_WAKING 0x00000200 121 #define TASK_NOLOAD 0x00000400 122 #define TASK_NEW 0x00000800 123 #define TASK_RTLOCK_WAIT 0x00001000 124 #define TASK_FREEZABLE 0x00002000 125 #define __TASK_FREEZABLE_UNSAFE (0x00004000 * IS_ENABLED(CONFIG_LOCKDEP)) 126 #define TASK_FROZEN 0x00008000 127 #define TASK_STATE_MAX 0x00010000 128 129 #define TASK_ANY (TASK_STATE_MAX-1) 130 131 /* 132 * DO NOT ADD ANY NEW USERS ! 133 */ 134 #define TASK_FREEZABLE_UNSAFE (TASK_FREEZABLE | __TASK_FREEZABLE_UNSAFE) 135 136 /* Convenience macros for the sake of set_current_state: */ 137 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 138 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 139 #define TASK_TRACED __TASK_TRACED 140 141 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD) 142 143 /* Convenience macros for the sake of wake_up(): */ 144 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 145 146 /* get_task_state(): */ 147 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 148 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 149 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \ 150 TASK_PARKED) 151 152 #define task_is_running(task) (READ_ONCE((task)->__state) == TASK_RUNNING) 153 154 #define task_is_traced(task) ((READ_ONCE(task->jobctl) & JOBCTL_TRACED) != 0) 155 #define task_is_stopped(task) ((READ_ONCE(task->jobctl) & JOBCTL_STOPPED) != 0) 156 #define task_is_stopped_or_traced(task) ((READ_ONCE(task->jobctl) & (JOBCTL_STOPPED | JOBCTL_TRACED)) != 0) 157 158 /* 159 * Special states are those that do not use the normal wait-loop pattern. See 160 * the comment with set_special_state(). 161 */ 162 #define is_special_task_state(state) \ 163 ((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | \ 164 TASK_DEAD | TASK_FROZEN)) 165 166 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 167 # define debug_normal_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_special_state_change(state_value) \ 174 do { \ 175 WARN_ON_ONCE(!is_special_task_state(state_value)); \ 176 current->task_state_change = _THIS_IP_; \ 177 } while (0) 178 179 # define debug_rtlock_wait_set_state() \ 180 do { \ 181 current->saved_state_change = current->task_state_change;\ 182 current->task_state_change = _THIS_IP_; \ 183 } while (0) 184 185 # define debug_rtlock_wait_restore_state() \ 186 do { \ 187 current->task_state_change = current->saved_state_change;\ 188 } while (0) 189 190 #else 191 # define debug_normal_state_change(cond) do { } while (0) 192 # define debug_special_state_change(cond) do { } while (0) 193 # define debug_rtlock_wait_set_state() do { } while (0) 194 # define debug_rtlock_wait_restore_state() do { } while (0) 195 #endif 196 197 #define trace_set_current_state(state_value) \ 198 do { \ 199 if (tracepoint_enabled(sched_set_state_tp)) \ 200 __trace_set_current_state(state_value); \ 201 } while (0) 202 203 /* 204 * set_current_state() includes a barrier so that the write of current->__state 205 * is correctly serialised wrt the caller's subsequent test of whether to 206 * actually sleep: 207 * 208 * for (;;) { 209 * set_current_state(TASK_UNINTERRUPTIBLE); 210 * if (CONDITION) 211 * break; 212 * 213 * schedule(); 214 * } 215 * __set_current_state(TASK_RUNNING); 216 * 217 * If the caller does not need such serialisation (because, for instance, the 218 * CONDITION test and condition change and wakeup are under the same lock) then 219 * use __set_current_state(). 220 * 221 * The above is typically ordered against the wakeup, which does: 222 * 223 * CONDITION = 1; 224 * wake_up_state(p, TASK_UNINTERRUPTIBLE); 225 * 226 * where wake_up_state()/try_to_wake_up() executes a full memory barrier before 227 * accessing p->__state. 228 * 229 * Wakeup will do: if (@state & p->__state) p->__state = TASK_RUNNING, that is, 230 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a 231 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING). 232 * 233 * However, with slightly different timing the wakeup TASK_RUNNING store can 234 * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not 235 * a problem either because that will result in one extra go around the loop 236 * and our @cond test will save the day. 237 * 238 * Also see the comments of try_to_wake_up(). 239 */ 240 #define __set_current_state(state_value) \ 241 do { \ 242 debug_normal_state_change((state_value)); \ 243 trace_set_current_state(state_value); \ 244 WRITE_ONCE(current->__state, (state_value)); \ 245 } while (0) 246 247 #define set_current_state(state_value) \ 248 do { \ 249 debug_normal_state_change((state_value)); \ 250 trace_set_current_state(state_value); \ 251 smp_store_mb(current->__state, (state_value)); \ 252 } while (0) 253 254 /* 255 * set_special_state() should be used for those states when the blocking task 256 * can not use the regular condition based wait-loop. In that case we must 257 * serialize against wakeups such that any possible in-flight TASK_RUNNING 258 * stores will not collide with our state change. 259 */ 260 #define set_special_state(state_value) \ 261 do { \ 262 unsigned long flags; /* may shadow */ \ 263 \ 264 raw_spin_lock_irqsave(¤t->pi_lock, flags); \ 265 debug_special_state_change((state_value)); \ 266 trace_set_current_state(state_value); \ 267 WRITE_ONCE(current->__state, (state_value)); \ 268 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \ 269 } while (0) 270 271 /* 272 * PREEMPT_RT specific variants for "sleeping" spin/rwlocks 273 * 274 * RT's spin/rwlock substitutions are state preserving. The state of the 275 * task when blocking on the lock is saved in task_struct::saved_state and 276 * restored after the lock has been acquired. These operations are 277 * serialized by task_struct::pi_lock against try_to_wake_up(). Any non RT 278 * lock related wakeups while the task is blocked on the lock are 279 * redirected to operate on task_struct::saved_state to ensure that these 280 * are not dropped. On restore task_struct::saved_state is set to 281 * TASK_RUNNING so any wakeup attempt redirected to saved_state will fail. 282 * 283 * The lock operation looks like this: 284 * 285 * current_save_and_set_rtlock_wait_state(); 286 * for (;;) { 287 * if (try_lock()) 288 * break; 289 * raw_spin_unlock_irq(&lock->wait_lock); 290 * schedule_rtlock(); 291 * raw_spin_lock_irq(&lock->wait_lock); 292 * set_current_state(TASK_RTLOCK_WAIT); 293 * } 294 * current_restore_rtlock_saved_state(); 295 */ 296 #define current_save_and_set_rtlock_wait_state() \ 297 do { \ 298 lockdep_assert_irqs_disabled(); \ 299 raw_spin_lock(¤t->pi_lock); \ 300 current->saved_state = current->__state; \ 301 debug_rtlock_wait_set_state(); \ 302 trace_set_current_state(TASK_RTLOCK_WAIT); \ 303 WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT); \ 304 raw_spin_unlock(¤t->pi_lock); \ 305 } while (0); 306 307 #define current_restore_rtlock_saved_state() \ 308 do { \ 309 lockdep_assert_irqs_disabled(); \ 310 raw_spin_lock(¤t->pi_lock); \ 311 debug_rtlock_wait_restore_state(); \ 312 trace_set_current_state(current->saved_state); \ 313 WRITE_ONCE(current->__state, current->saved_state); \ 314 current->saved_state = TASK_RUNNING; \ 315 raw_spin_unlock(¤t->pi_lock); \ 316 } while (0); 317 318 #define get_current_state() READ_ONCE(current->__state) 319 320 /* 321 * Define the task command name length as enum, then it can be visible to 322 * BPF programs. 323 */ 324 enum { 325 TASK_COMM_LEN = 16, 326 }; 327 328 extern void sched_tick(void); 329 330 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 331 332 extern long schedule_timeout(long timeout); 333 extern long schedule_timeout_interruptible(long timeout); 334 extern long schedule_timeout_killable(long timeout); 335 extern long schedule_timeout_uninterruptible(long timeout); 336 extern long schedule_timeout_idle(long timeout); 337 asmlinkage void schedule(void); 338 extern void schedule_preempt_disabled(void); 339 asmlinkage void preempt_schedule_irq(void); 340 #ifdef CONFIG_PREEMPT_RT 341 extern void schedule_rtlock(void); 342 #endif 343 344 extern int __must_check io_schedule_prepare(void); 345 extern void io_schedule_finish(int token); 346 extern long io_schedule_timeout(long timeout); 347 extern void io_schedule(void); 348 349 /* wrapper functions to trace from this header file */ 350 DECLARE_TRACEPOINT(sched_set_state_tp); 351 extern void __trace_set_current_state(int state_value); 352 DECLARE_TRACEPOINT(sched_set_need_resched_tp); 353 extern void __trace_set_need_resched(struct task_struct *curr, int tif); 354 355 /** 356 * struct prev_cputime - snapshot of system and user cputime 357 * @utime: time spent in user mode 358 * @stime: time spent in system mode 359 * @lock: protects the above two fields 360 * 361 * Stores previous user/system time values such that we can guarantee 362 * monotonicity. 363 */ 364 struct prev_cputime { 365 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 366 u64 utime; 367 u64 stime; 368 raw_spinlock_t lock; 369 #endif 370 }; 371 372 enum vtime_state { 373 /* Task is sleeping or running in a CPU with VTIME inactive: */ 374 VTIME_INACTIVE = 0, 375 /* Task is idle */ 376 VTIME_IDLE, 377 /* Task runs in kernelspace in a CPU with VTIME active: */ 378 VTIME_SYS, 379 /* Task runs in userspace in a CPU with VTIME active: */ 380 VTIME_USER, 381 /* Task runs as guests in a CPU with VTIME active: */ 382 VTIME_GUEST, 383 }; 384 385 struct vtime { 386 seqcount_t seqcount; 387 unsigned long long starttime; 388 enum vtime_state state; 389 unsigned int cpu; 390 u64 utime; 391 u64 stime; 392 u64 gtime; 393 }; 394 395 /* 396 * Utilization clamp constraints. 397 * @UCLAMP_MIN: Minimum utilization 398 * @UCLAMP_MAX: Maximum utilization 399 * @UCLAMP_CNT: Utilization clamp constraints count 400 */ 401 enum uclamp_id { 402 UCLAMP_MIN = 0, 403 UCLAMP_MAX, 404 UCLAMP_CNT 405 }; 406 407 extern struct root_domain def_root_domain; 408 extern struct mutex sched_domains_mutex; 409 extern void sched_domains_mutex_lock(void); 410 extern void sched_domains_mutex_unlock(void); 411 412 struct sched_param { 413 int sched_priority; 414 }; 415 416 struct sched_info { 417 #ifdef CONFIG_SCHED_INFO 418 /* Cumulative counters: */ 419 420 /* # of times we have run on this CPU: */ 421 unsigned long pcount; 422 423 /* Time spent waiting on a runqueue: */ 424 unsigned long long run_delay; 425 426 /* Max time spent waiting on a runqueue: */ 427 unsigned long long max_run_delay; 428 429 /* Min time spent waiting on a runqueue: */ 430 unsigned long long min_run_delay; 431 432 /* Timestamps: */ 433 434 /* When did we last run on a CPU? */ 435 unsigned long long last_arrival; 436 437 /* When were we last queued to run? */ 438 unsigned long long last_queued; 439 440 /* Timestamp of max time spent waiting on a runqueue: */ 441 struct timespec64 max_run_delay_ts; 442 443 #endif /* CONFIG_SCHED_INFO */ 444 }; 445 446 /* 447 * Integer metrics need fixed point arithmetic, e.g., sched/fair 448 * has a few: load, load_avg, util_avg, freq, and capacity. 449 * 450 * We define a basic fixed point arithmetic range, and then formalize 451 * all these metrics based on that basic range. 452 */ 453 # define SCHED_FIXEDPOINT_SHIFT 10 454 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT) 455 456 /* Increase resolution of cpu_capacity calculations */ 457 # define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT 458 # define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) 459 460 struct load_weight { 461 unsigned long weight; 462 u32 inv_weight; 463 }; 464 465 /* 466 * The load/runnable/util_avg accumulates an infinite geometric series 467 * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c). 468 * 469 * [load_avg definition] 470 * 471 * load_avg = runnable% * scale_load_down(load) 472 * 473 * [runnable_avg definition] 474 * 475 * runnable_avg = runnable% * SCHED_CAPACITY_SCALE 476 * 477 * [util_avg definition] 478 * 479 * util_avg = running% * SCHED_CAPACITY_SCALE 480 * 481 * where runnable% is the time ratio that a sched_entity is runnable and 482 * running% the time ratio that a sched_entity is running. 483 * 484 * For cfs_rq, they are the aggregated values of all runnable and blocked 485 * sched_entities. 486 * 487 * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU 488 * capacity scaling. The scaling is done through the rq_clock_pelt that is used 489 * for computing those signals (see update_rq_clock_pelt()) 490 * 491 * N.B., the above ratios (runnable% and running%) themselves are in the 492 * range of [0, 1]. To do fixed point arithmetics, we therefore scale them 493 * to as large a range as necessary. This is for example reflected by 494 * util_avg's SCHED_CAPACITY_SCALE. 495 * 496 * [Overflow issue] 497 * 498 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities 499 * with the highest load (=88761), always runnable on a single cfs_rq, 500 * and should not overflow as the number already hits PID_MAX_LIMIT. 501 * 502 * For all other cases (including 32-bit kernels), struct load_weight's 503 * weight will overflow first before we do, because: 504 * 505 * Max(load_avg) <= Max(load.weight) 506 * 507 * Then it is the load_weight's responsibility to consider overflow 508 * issues. 509 */ 510 struct sched_avg { 511 u64 last_update_time; 512 u64 load_sum; 513 u64 runnable_sum; 514 u32 util_sum; 515 u32 period_contrib; 516 unsigned long load_avg; 517 unsigned long runnable_avg; 518 unsigned long util_avg; 519 unsigned int util_est; 520 } ____cacheline_aligned; 521 522 /* 523 * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg 524 * updates. When a task is dequeued, its util_est should not be updated if its 525 * util_avg has not been updated in the meantime. 526 * This information is mapped into the MSB bit of util_est at dequeue time. 527 * Since max value of util_est for a task is 1024 (PELT util_avg for a task) 528 * it is safe to use MSB. 529 */ 530 #define UTIL_EST_WEIGHT_SHIFT 2 531 #define UTIL_AVG_UNCHANGED 0x80000000 532 533 struct sched_statistics { 534 #ifdef CONFIG_SCHEDSTATS 535 u64 wait_start; 536 u64 wait_max; 537 u64 wait_count; 538 u64 wait_sum; 539 u64 iowait_count; 540 u64 iowait_sum; 541 542 u64 sleep_start; 543 u64 sleep_max; 544 s64 sum_sleep_runtime; 545 546 u64 block_start; 547 u64 block_max; 548 s64 sum_block_runtime; 549 550 s64 exec_max; 551 u64 slice_max; 552 553 u64 nr_migrations_cold; 554 u64 nr_failed_migrations_affine; 555 u64 nr_failed_migrations_running; 556 u64 nr_failed_migrations_hot; 557 u64 nr_forced_migrations; 558 559 u64 nr_wakeups; 560 u64 nr_wakeups_sync; 561 u64 nr_wakeups_migrate; 562 u64 nr_wakeups_local; 563 u64 nr_wakeups_remote; 564 u64 nr_wakeups_affine; 565 u64 nr_wakeups_affine_attempts; 566 u64 nr_wakeups_passive; 567 u64 nr_wakeups_idle; 568 569 #ifdef CONFIG_SCHED_CORE 570 u64 core_forceidle_sum; 571 #endif 572 #endif /* CONFIG_SCHEDSTATS */ 573 } ____cacheline_aligned; 574 575 struct sched_entity { 576 /* For load-balancing: */ 577 struct load_weight load; 578 struct rb_node run_node; 579 u64 deadline; 580 u64 min_vruntime; 581 u64 min_slice; 582 u64 max_slice; 583 584 struct list_head group_node; 585 unsigned char on_rq; 586 unsigned char sched_delayed; 587 unsigned char rel_deadline; 588 unsigned char custom_slice; 589 /* hole */ 590 591 u64 exec_start; 592 u64 sum_exec_runtime; 593 u64 prev_sum_exec_runtime; 594 u64 vruntime; 595 /* Approximated virtual lag: */ 596 s64 vlag; 597 /* 'Protected' deadline, to give out minimum quantums: */ 598 u64 vprot; 599 u64 slice; 600 601 u64 nr_migrations; 602 603 #ifdef CONFIG_FAIR_GROUP_SCHED 604 int depth; 605 struct sched_entity *parent; 606 /* rq on which this entity is (to be) queued: */ 607 struct cfs_rq *cfs_rq; 608 /* rq "owned" by this entity/group: */ 609 struct cfs_rq *my_q; 610 /* cached value of my_q->h_nr_running */ 611 unsigned long runnable_weight; 612 #endif 613 614 /* 615 * Per entity load average tracking. 616 * 617 * Put into separate cache line so it does not 618 * collide with read-mostly values above. 619 */ 620 struct sched_avg avg; 621 }; 622 623 struct sched_rt_entity { 624 struct list_head run_list; 625 unsigned long timeout; 626 unsigned long watchdog_stamp; 627 unsigned int time_slice; 628 unsigned short on_rq; 629 unsigned short on_list; 630 631 struct sched_rt_entity *back; 632 #ifdef CONFIG_RT_GROUP_SCHED 633 struct sched_rt_entity *parent; 634 /* rq on which this entity is (to be) queued: */ 635 struct rt_rq *rt_rq; 636 /* rq "owned" by this entity/group: */ 637 struct rt_rq *my_q; 638 #endif 639 } __randomize_layout; 640 641 struct rq_flags; 642 typedef struct task_struct *(*dl_server_pick_f)(struct sched_dl_entity *, struct rq_flags *rf); 643 644 struct sched_dl_entity { 645 struct rb_node rb_node; 646 647 /* 648 * Original scheduling parameters. Copied here from sched_attr 649 * during sched_setattr(), they will remain the same until 650 * the next sched_setattr(). 651 */ 652 u64 dl_runtime; /* Maximum runtime for each instance */ 653 u64 dl_deadline; /* Relative deadline of each instance */ 654 u64 dl_period; /* Separation of two instances (period) */ 655 u64 dl_bw; /* dl_runtime / dl_period */ 656 u64 dl_density; /* dl_runtime / dl_deadline */ 657 658 /* 659 * Actual scheduling parameters. Initialized with the values above, 660 * they are continuously updated during task execution. Note that 661 * the remaining runtime could be < 0 in case we are in overrun. 662 */ 663 s64 runtime; /* Remaining runtime for this instance */ 664 u64 deadline; /* Absolute deadline for this instance */ 665 unsigned int flags; /* Specifying the scheduler behaviour */ 666 667 /* 668 * Some bool flags: 669 * 670 * @dl_throttled tells if we exhausted the runtime. If so, the 671 * task has to wait for a replenishment to be performed at the 672 * next firing of dl_timer. 673 * 674 * @dl_yielded tells if task gave up the CPU before consuming 675 * all its available runtime during the last job. 676 * 677 * @dl_non_contending tells if the task is inactive while still 678 * contributing to the active utilization. In other words, it 679 * indicates if the inactive timer has been armed and its handler 680 * has not been executed yet. This flag is useful to avoid race 681 * conditions between the inactive timer handler and the wakeup 682 * code. 683 * 684 * @dl_overrun tells if the task asked to be informed about runtime 685 * overruns. 686 * 687 * @dl_server tells if this is a server entity. 688 * 689 * @dl_server_active tells if the dlserver is active(started). 690 * dlserver is started on first cfs enqueue on an idle runqueue 691 * and is stopped when a dequeue results in 0 cfs tasks on the 692 * runqueue. In other words, dlserver is active only when cpu's 693 * runqueue has atleast one cfs task. 694 * 695 * @dl_defer tells if this is a deferred or regular server. For 696 * now only defer server exists. 697 * 698 * @dl_defer_armed tells if the deferrable server is waiting 699 * for the replenishment timer to activate it. 700 * 701 * @dl_defer_running tells if the deferrable server is actually 702 * running, skipping the defer phase. 703 * 704 * @dl_defer_idle tracks idle state 705 */ 706 unsigned int dl_throttled : 1; 707 unsigned int dl_yielded : 1; 708 unsigned int dl_non_contending : 1; 709 unsigned int dl_overrun : 1; 710 unsigned int dl_server : 1; 711 unsigned int dl_server_active : 1; 712 unsigned int dl_defer : 1; 713 unsigned int dl_defer_armed : 1; 714 unsigned int dl_defer_running : 1; 715 unsigned int dl_defer_idle : 1; 716 717 /* 718 * Bandwidth enforcement timer. Each -deadline task has its 719 * own bandwidth to be enforced, thus we need one timer per task. 720 */ 721 struct hrtimer dl_timer; 722 723 /* 724 * Inactive timer, responsible for decreasing the active utilization 725 * at the "0-lag time". When a -deadline task blocks, it contributes 726 * to GRUB's active utilization until the "0-lag time", hence a 727 * timer is needed to decrease the active utilization at the correct 728 * time. 729 */ 730 struct hrtimer inactive_timer; 731 732 /* 733 * Bits for DL-server functionality. Also see the comment near 734 * dl_server_update(). 735 * 736 * @rq the runqueue this server is for 737 */ 738 struct rq *rq; 739 dl_server_pick_f server_pick_task; 740 741 #ifdef CONFIG_RT_MUTEXES 742 /* 743 * Priority Inheritance. When a DEADLINE scheduling entity is boosted 744 * pi_se points to the donor, otherwise points to the dl_se it belongs 745 * to (the original one/itself). 746 */ 747 struct sched_dl_entity *pi_se; 748 #endif 749 }; 750 751 #ifdef CONFIG_UCLAMP_TASK 752 /* Number of utilization clamp buckets (shorter alias) */ 753 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT 754 755 /* 756 * Utilization clamp for a scheduling entity 757 * @value: clamp value "assigned" to a se 758 * @bucket_id: bucket index corresponding to the "assigned" value 759 * @active: the se is currently refcounted in a rq's bucket 760 * @user_defined: the requested clamp value comes from user-space 761 * 762 * The bucket_id is the index of the clamp bucket matching the clamp value 763 * which is pre-computed and stored to avoid expensive integer divisions from 764 * the fast path. 765 * 766 * The active bit is set whenever a task has got an "effective" value assigned, 767 * which can be different from the clamp value "requested" from user-space. 768 * This allows to know a task is refcounted in the rq's bucket corresponding 769 * to the "effective" bucket_id. 770 * 771 * The user_defined bit is set whenever a task has got a task-specific clamp 772 * value requested from userspace, i.e. the system defaults apply to this task 773 * just as a restriction. This allows to relax default clamps when a less 774 * restrictive task-specific value has been requested, thus allowing to 775 * implement a "nice" semantic. For example, a task running with a 20% 776 * default boost can still drop its own boosting to 0%. 777 */ 778 struct uclamp_se { 779 unsigned int value : bits_per(SCHED_CAPACITY_SCALE); 780 unsigned int bucket_id : bits_per(UCLAMP_BUCKETS); 781 unsigned int active : 1; 782 unsigned int user_defined : 1; 783 }; 784 #endif /* CONFIG_UCLAMP_TASK */ 785 786 union rcu_special { 787 struct { 788 u8 blocked; 789 u8 need_qs; 790 u8 exp_hint; /* Hint for performance. */ 791 u8 need_mb; /* Readers need smp_mb(). */ 792 } b; /* Bits. */ 793 u32 s; /* Set of bits. */ 794 }; 795 796 enum perf_event_task_context { 797 perf_invalid_context = -1, 798 perf_hw_context = 0, 799 perf_sw_context, 800 perf_nr_task_contexts, 801 }; 802 803 /* 804 * Number of contexts where an event can trigger: 805 * task, softirq, hardirq, nmi. 806 */ 807 #define PERF_NR_CONTEXTS 4 808 809 struct wake_q_node { 810 struct wake_q_node *next; 811 }; 812 813 struct kmap_ctrl { 814 #ifdef CONFIG_KMAP_LOCAL 815 int idx; 816 pte_t pteval[KM_MAX_IDX]; 817 #endif 818 }; 819 820 struct task_struct { 821 #ifdef CONFIG_THREAD_INFO_IN_TASK 822 /* 823 * For reasons of header soup (see current_thread_info()), this 824 * must be the first element of task_struct. 825 */ 826 struct thread_info thread_info; 827 #endif 828 unsigned int __state; 829 830 /* saved state for "spinlock sleepers" */ 831 unsigned int saved_state; 832 833 /* 834 * This begins the randomizable portion of task_struct. Only 835 * scheduling-critical items should be added above here. 836 */ 837 randomized_struct_fields_start 838 839 void *stack; 840 refcount_t usage; 841 /* Per task flags (PF_*), defined further below: */ 842 unsigned int flags; 843 unsigned int ptrace; 844 845 #ifdef CONFIG_MEM_ALLOC_PROFILING 846 struct alloc_tag *alloc_tag; 847 #endif 848 849 int on_cpu; 850 struct __call_single_node wake_entry; 851 unsigned int wakee_flips; 852 unsigned long wakee_flip_decay_ts; 853 struct task_struct *last_wakee; 854 855 /* 856 * recent_used_cpu is initially set as the last CPU used by a task 857 * that wakes affine another task. Waker/wakee relationships can 858 * push tasks around a CPU where each wakeup moves to the next one. 859 * Tracking a recently used CPU allows a quick search for a recently 860 * used CPU that may be idle. 861 */ 862 int recent_used_cpu; 863 int wake_cpu; 864 int on_rq; 865 866 int prio; 867 int static_prio; 868 int normal_prio; 869 unsigned int rt_priority; 870 871 struct sched_entity se; 872 struct sched_rt_entity rt; 873 struct sched_dl_entity dl; 874 struct sched_dl_entity *dl_server; 875 #ifdef CONFIG_SCHED_CLASS_EXT 876 struct sched_ext_entity scx; 877 #endif 878 const struct sched_class *sched_class; 879 880 #ifdef CONFIG_SCHED_CORE 881 struct rb_node core_node; 882 unsigned long core_cookie; 883 unsigned int core_occupation; 884 #endif 885 886 #ifdef CONFIG_CGROUP_SCHED 887 struct task_group *sched_task_group; 888 #ifdef CONFIG_CFS_BANDWIDTH 889 struct callback_head sched_throttle_work; 890 struct list_head throttle_node; 891 bool throttled; 892 #endif 893 #endif 894 895 896 #ifdef CONFIG_UCLAMP_TASK 897 /* 898 * Clamp values requested for a scheduling entity. 899 * Must be updated with task_rq_lock() held. 900 */ 901 struct uclamp_se uclamp_req[UCLAMP_CNT]; 902 /* 903 * Effective clamp values used for a scheduling entity. 904 * Must be updated with task_rq_lock() held. 905 */ 906 struct uclamp_se uclamp[UCLAMP_CNT]; 907 #endif 908 909 struct sched_statistics stats; 910 911 #ifdef CONFIG_PREEMPT_NOTIFIERS 912 /* List of struct preempt_notifier: */ 913 struct hlist_head preempt_notifiers; 914 #endif 915 916 #ifdef CONFIG_BLK_DEV_IO_TRACE 917 unsigned int btrace_seq; 918 #endif 919 920 unsigned int policy; 921 unsigned long max_allowed_capacity; 922 int nr_cpus_allowed; 923 const cpumask_t *cpus_ptr; 924 cpumask_t *user_cpus_ptr; 925 cpumask_t cpus_mask; 926 void *migration_pending; 927 unsigned short migration_disabled; 928 unsigned short migration_flags; 929 930 #ifdef CONFIG_PREEMPT_RCU 931 int rcu_read_lock_nesting; 932 union rcu_special rcu_read_unlock_special; 933 struct list_head rcu_node_entry; 934 struct rcu_node *rcu_blocked_node; 935 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 936 937 #ifdef CONFIG_TASKS_RCU 938 unsigned long rcu_tasks_nvcsw; 939 u8 rcu_tasks_holdout; 940 u8 rcu_tasks_idx; 941 int rcu_tasks_idle_cpu; 942 struct list_head rcu_tasks_holdout_list; 943 int rcu_tasks_exit_cpu; 944 struct list_head rcu_tasks_exit_list; 945 #endif /* #ifdef CONFIG_TASKS_RCU */ 946 947 #ifdef CONFIG_TASKS_TRACE_RCU 948 int trc_reader_nesting; 949 struct srcu_ctr __percpu *trc_reader_scp; 950 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */ 951 952 struct sched_info sched_info; 953 954 struct list_head tasks; 955 struct plist_node pushable_tasks; 956 struct rb_node pushable_dl_tasks; 957 958 struct mm_struct *mm; 959 struct mm_struct *active_mm; 960 961 int exit_state; 962 int exit_code; 963 int exit_signal; 964 /* The signal sent when the parent dies: */ 965 int pdeath_signal; 966 /* JOBCTL_*, siglock protected: */ 967 unsigned long jobctl; 968 969 /* Used for emulating ABI behavior of previous Linux versions: */ 970 unsigned int personality; 971 972 /* Scheduler bits, serialized by scheduler locks: */ 973 unsigned sched_reset_on_fork:1; 974 unsigned sched_contributes_to_load:1; 975 unsigned sched_migrated:1; 976 unsigned sched_task_hot:1; 977 978 /* Force alignment to the next boundary: */ 979 unsigned :0; 980 981 /* Unserialized, strictly 'current' */ 982 983 /* 984 * This field must not be in the scheduler word above due to wakelist 985 * queueing no longer being serialized by p->on_cpu. However: 986 * 987 * p->XXX = X; ttwu() 988 * schedule() if (p->on_rq && ..) // false 989 * smp_mb__after_spinlock(); if (smp_load_acquire(&p->on_cpu) && //true 990 * deactivate_task() ttwu_queue_wakelist()) 991 * p->on_rq = 0; p->sched_remote_wakeup = Y; 992 * 993 * guarantees all stores of 'current' are visible before 994 * ->sched_remote_wakeup gets used, so it can be in this word. 995 */ 996 unsigned sched_remote_wakeup:1; 997 #ifdef CONFIG_RT_MUTEXES 998 unsigned sched_rt_mutex:1; 999 #endif 1000 1001 /* Bit to tell TOMOYO we're in execve(): */ 1002 unsigned in_execve:1; 1003 unsigned in_iowait:1; 1004 #ifndef TIF_RESTORE_SIGMASK 1005 unsigned restore_sigmask:1; 1006 #endif 1007 #ifdef CONFIG_MEMCG_V1 1008 unsigned in_user_fault:1; 1009 #endif 1010 #ifdef CONFIG_LRU_GEN 1011 /* whether the LRU algorithm may apply to this access */ 1012 unsigned in_lru_fault:1; 1013 #endif 1014 #ifdef CONFIG_COMPAT_BRK 1015 unsigned brk_randomized:1; 1016 #endif 1017 #ifdef CONFIG_CGROUPS 1018 /* disallow userland-initiated cgroup migration */ 1019 unsigned no_cgroup_migration:1; 1020 /* task is frozen/stopped (used by the cgroup freezer) */ 1021 unsigned frozen:1; 1022 #endif 1023 #ifdef CONFIG_BLK_CGROUP 1024 unsigned use_memdelay:1; 1025 #endif 1026 #ifdef CONFIG_PSI 1027 /* Stalled due to lack of memory */ 1028 unsigned in_memstall:1; 1029 #endif 1030 #ifdef CONFIG_PAGE_OWNER 1031 /* Used by page_owner=on to detect recursion in page tracking. */ 1032 unsigned in_page_owner:1; 1033 #endif 1034 #ifdef CONFIG_EVENTFD 1035 /* Recursion prevention for eventfd_signal() */ 1036 unsigned in_eventfd:1; 1037 #endif 1038 #ifdef CONFIG_ARCH_HAS_CPU_PASID 1039 unsigned pasid_activated:1; 1040 #endif 1041 #ifdef CONFIG_X86_BUS_LOCK_DETECT 1042 unsigned reported_split_lock:1; 1043 #endif 1044 #ifdef CONFIG_TASK_DELAY_ACCT 1045 /* delay due to memory thrashing */ 1046 unsigned in_thrashing:1; 1047 #endif 1048 unsigned in_nf_duplicate:1; 1049 #ifdef CONFIG_PREEMPT_RT 1050 struct netdev_xmit net_xmit; 1051 #endif 1052 unsigned long atomic_flags; /* Flags requiring atomic access. */ 1053 1054 struct restart_block restart_block; 1055 1056 pid_t pid; 1057 pid_t tgid; 1058 1059 #ifdef CONFIG_STACKPROTECTOR 1060 /* Canary value for the -fstack-protector GCC feature: */ 1061 unsigned long stack_canary; 1062 #endif 1063 /* 1064 * Pointers to the (original) parent process, youngest child, younger sibling, 1065 * older sibling, respectively. (p->father can be replaced with 1066 * p->real_parent->pid) 1067 */ 1068 1069 /* Real parent process: */ 1070 struct task_struct __rcu *real_parent; 1071 1072 /* Recipient of SIGCHLD, wait4() reports: */ 1073 struct task_struct __rcu *parent; 1074 1075 /* 1076 * Children/sibling form the list of natural children: 1077 */ 1078 struct list_head children; 1079 struct list_head sibling; 1080 struct task_struct *group_leader; 1081 1082 /* 1083 * 'ptraced' is the list of tasks this task is using ptrace() on. 1084 * 1085 * This includes both natural children and PTRACE_ATTACH targets. 1086 * 'ptrace_entry' is this task's link on the p->parent->ptraced list. 1087 */ 1088 struct list_head ptraced; 1089 struct list_head ptrace_entry; 1090 1091 /* PID/PID hash table linkage. */ 1092 struct pid *thread_pid; 1093 struct hlist_node pid_links[PIDTYPE_MAX]; 1094 struct list_head thread_node; 1095 1096 struct completion *vfork_done; 1097 1098 /* CLONE_CHILD_SETTID: */ 1099 int __user *set_child_tid; 1100 1101 /* CLONE_CHILD_CLEARTID: */ 1102 int __user *clear_child_tid; 1103 1104 /* PF_KTHREAD | PF_IO_WORKER */ 1105 void *worker_private; 1106 1107 u64 utime; 1108 u64 stime; 1109 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME 1110 u64 utimescaled; 1111 u64 stimescaled; 1112 #endif 1113 u64 gtime; 1114 struct prev_cputime prev_cputime; 1115 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1116 struct vtime vtime; 1117 #endif 1118 1119 #ifdef CONFIG_NO_HZ_FULL 1120 atomic_t tick_dep_mask; 1121 #endif 1122 /* Context switch counts: */ 1123 unsigned long nvcsw; 1124 unsigned long nivcsw; 1125 1126 /* Monotonic time in nsecs: */ 1127 u64 start_time; 1128 1129 /* Boot based time in nsecs: */ 1130 u64 start_boottime; 1131 1132 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */ 1133 unsigned long min_flt; 1134 unsigned long maj_flt; 1135 1136 /* Empty if CONFIG_POSIX_CPUTIMERS=n */ 1137 struct posix_cputimers posix_cputimers; 1138 1139 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK 1140 struct posix_cputimers_work posix_cputimers_work; 1141 #endif 1142 1143 /* Process credentials: */ 1144 1145 /* Tracer's credentials at attach: */ 1146 const struct cred __rcu *ptracer_cred; 1147 1148 /* Objective and real subjective task credentials (COW): */ 1149 const struct cred __rcu *real_cred; 1150 1151 /* Effective (overridable) subjective task credentials (COW): */ 1152 const struct cred __rcu *cred; 1153 1154 #ifdef CONFIG_KEYS 1155 /* Cached requested key. */ 1156 struct key *cached_requested_key; 1157 #endif 1158 1159 /* 1160 * executable name, excluding path. 1161 * 1162 * - normally initialized begin_new_exec() 1163 * - set it with set_task_comm() 1164 * - strscpy_pad() to ensure it is always NUL-terminated and 1165 * zero-padded 1166 * - task_lock() to ensure the operation is atomic and the name is 1167 * fully updated. 1168 */ 1169 char comm[TASK_COMM_LEN]; 1170 1171 struct nameidata *nameidata; 1172 1173 #ifdef CONFIG_SYSVIPC 1174 struct sysv_sem sysvsem; 1175 struct sysv_shm sysvshm; 1176 #endif 1177 #ifdef CONFIG_DETECT_HUNG_TASK 1178 unsigned long last_switch_count; 1179 unsigned long last_switch_time; 1180 #endif 1181 /* Filesystem information: */ 1182 struct fs_struct *fs; 1183 1184 /* Open file information: */ 1185 struct files_struct *files; 1186 1187 #ifdef CONFIG_IO_URING 1188 struct io_uring_task *io_uring; 1189 struct io_restriction *io_uring_restrict; 1190 #endif 1191 1192 /* Namespaces: */ 1193 struct nsproxy *nsproxy; 1194 1195 /* Signal handlers: */ 1196 struct signal_struct *signal; 1197 struct sighand_struct __rcu *sighand; 1198 sigset_t blocked; 1199 sigset_t real_blocked; 1200 /* Restored if set_restore_sigmask() was used: */ 1201 sigset_t saved_sigmask; 1202 struct sigpending pending; 1203 unsigned long sas_ss_sp; 1204 size_t sas_ss_size; 1205 unsigned int sas_ss_flags; 1206 1207 struct callback_head *task_works; 1208 1209 #ifdef CONFIG_AUDIT 1210 #ifdef CONFIG_AUDITSYSCALL 1211 struct audit_context *audit_context; 1212 #endif 1213 kuid_t loginuid; 1214 unsigned int sessionid; 1215 #endif 1216 struct seccomp seccomp; 1217 struct syscall_user_dispatch syscall_dispatch; 1218 1219 /* Thread group tracking: */ 1220 u64 parent_exec_id; 1221 u64 self_exec_id; 1222 1223 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */ 1224 spinlock_t alloc_lock; 1225 1226 /* Protection of the PI data structures: */ 1227 raw_spinlock_t pi_lock; 1228 1229 struct wake_q_node wake_q; 1230 1231 #ifdef CONFIG_RT_MUTEXES 1232 /* PI waiters blocked on a rt_mutex held by this task: */ 1233 struct rb_root_cached pi_waiters; 1234 /* Updated under owner's pi_lock and rq lock */ 1235 struct task_struct *pi_top_task; 1236 /* Deadlock detection and priority inheritance handling: */ 1237 struct rt_mutex_waiter *pi_blocked_on; 1238 #endif 1239 1240 struct mutex *blocked_on; /* lock we're blocked on */ 1241 1242 #ifdef CONFIG_DETECT_HUNG_TASK_BLOCKER 1243 /* 1244 * Encoded lock address causing task block (lower 2 bits = type from 1245 * <linux/hung_task.h>). Accessed via hung_task_*() helpers. 1246 */ 1247 unsigned long blocker; 1248 #endif 1249 1250 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1251 int non_block_count; 1252 #endif 1253 1254 #ifdef CONFIG_TRACE_IRQFLAGS 1255 struct irqtrace_events irqtrace; 1256 unsigned int hardirq_threaded; 1257 u64 hardirq_chain_key; 1258 int softirqs_enabled; 1259 int softirq_context; 1260 int irq_config; 1261 #endif 1262 #ifdef CONFIG_PREEMPT_RT 1263 int softirq_disable_cnt; 1264 #endif 1265 1266 #ifdef CONFIG_LOCKDEP 1267 # define MAX_LOCK_DEPTH 48UL 1268 u64 curr_chain_key; 1269 int lockdep_depth; 1270 unsigned int lockdep_recursion; 1271 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1272 #endif 1273 1274 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP) 1275 unsigned int in_ubsan; 1276 #endif 1277 1278 /* Journalling filesystem info: */ 1279 void *journal_info; 1280 1281 /* Stacked block device info: */ 1282 struct bio_list *bio_list; 1283 1284 /* Stack plugging: */ 1285 struct blk_plug *plug; 1286 1287 /* VM state: */ 1288 struct reclaim_state *reclaim_state; 1289 1290 struct io_context *io_context; 1291 1292 #ifdef CONFIG_COMPACTION 1293 struct capture_control *capture_control; 1294 #endif 1295 /* Ptrace state: */ 1296 unsigned long ptrace_message; 1297 kernel_siginfo_t *last_siginfo; 1298 1299 struct task_io_accounting ioac; 1300 #ifdef CONFIG_PSI 1301 /* Pressure stall state */ 1302 unsigned int psi_flags; 1303 #endif 1304 #ifdef CONFIG_TASK_XACCT 1305 /* Accumulated RSS usage: */ 1306 u64 acct_rss_mem1; 1307 /* Accumulated virtual memory usage: */ 1308 u64 acct_vm_mem1; 1309 /* stime + utime since last update: */ 1310 u64 acct_timexpd; 1311 #endif 1312 #ifdef CONFIG_CPUSETS 1313 /* Protected by ->alloc_lock: */ 1314 nodemask_t mems_allowed; 1315 /* Sequence number to catch updates: */ 1316 seqcount_spinlock_t mems_allowed_seq; 1317 int cpuset_mem_spread_rotor; 1318 #endif 1319 #ifdef CONFIG_CGROUPS 1320 /* Control Group info protected by css_set_lock: */ 1321 struct css_set __rcu *cgroups; 1322 /* cg_list protected by css_set_lock and tsk->alloc_lock: */ 1323 struct list_head cg_list; 1324 #ifdef CONFIG_PREEMPT_RT 1325 struct llist_node cg_dead_lnode; 1326 #endif /* CONFIG_PREEMPT_RT */ 1327 #endif /* CONFIG_CGROUPS */ 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 struct rseq_data rseq; 1410 struct sched_mm_cid mm_cid; 1411 1412 struct tlbflush_unmap_batch tlb_ubc; 1413 1414 /* Cache last used pipe for splice(): */ 1415 struct pipe_inode_info *splice_pipe; 1416 1417 struct page_frag task_frag; 1418 1419 #ifdef CONFIG_ARCH_HAS_LAZY_MMU_MODE 1420 struct lazy_mmu_state lazy_mmu_state; 1421 #endif 1422 1423 #ifdef CONFIG_TASK_DELAY_ACCT 1424 struct task_delay_info *delays; 1425 #endif 1426 1427 #ifdef CONFIG_FAULT_INJECTION 1428 int make_it_fail; 1429 unsigned int fail_nth; 1430 #endif 1431 /* 1432 * When (nr_dirtied >= nr_dirtied_pause), it's time to call 1433 * balance_dirty_pages() for a dirty throttling pause: 1434 */ 1435 int nr_dirtied; 1436 int nr_dirtied_pause; 1437 /* Start of a write-and-pause period: */ 1438 unsigned long dirty_paused_when; 1439 1440 #ifdef CONFIG_LATENCYTOP 1441 int latency_record_count; 1442 struct latency_record latency_record[LT_SAVECOUNT]; 1443 #endif 1444 /* 1445 * Time slack values; these are used to round up poll() and 1446 * select() etc timeout values. These are in nanoseconds. 1447 */ 1448 u64 timer_slack_ns; 1449 u64 default_timer_slack_ns; 1450 1451 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) 1452 unsigned int kasan_depth; 1453 #endif 1454 1455 #ifdef CONFIG_KCSAN 1456 struct kcsan_ctx kcsan_ctx; 1457 #ifdef CONFIG_TRACE_IRQFLAGS 1458 struct irqtrace_events kcsan_save_irqtrace; 1459 #endif 1460 #ifdef CONFIG_KCSAN_WEAK_MEMORY 1461 int kcsan_stack_depth; 1462 #endif 1463 #endif 1464 1465 #ifdef CONFIG_KMSAN 1466 struct kmsan_ctx kmsan_ctx; 1467 #endif 1468 1469 #if IS_ENABLED(CONFIG_KUNIT) 1470 struct kunit *kunit_test; 1471 #endif 1472 1473 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1474 /* Index of current stored address in ret_stack: */ 1475 int curr_ret_stack; 1476 int curr_ret_depth; 1477 1478 /* Stack of return addresses for return function tracing: */ 1479 unsigned long *ret_stack; 1480 1481 /* Timestamp for last schedule: */ 1482 unsigned long long ftrace_timestamp; 1483 unsigned long long ftrace_sleeptime; 1484 1485 /* 1486 * Number of functions that haven't been traced 1487 * because of depth overrun: 1488 */ 1489 atomic_t trace_overrun; 1490 1491 /* Pause tracing: */ 1492 atomic_t tracing_graph_pause; 1493 #endif 1494 1495 #ifdef CONFIG_TRACING 1496 /* Bitmask and counter of trace recursion: */ 1497 unsigned long trace_recursion; 1498 #endif /* CONFIG_TRACING */ 1499 1500 #ifdef CONFIG_KCOV 1501 /* See kernel/kcov.c for more details. */ 1502 1503 /* Coverage collection mode enabled for this task (0 if disabled): */ 1504 unsigned int kcov_mode; 1505 1506 /* Size of the kcov_area: */ 1507 unsigned int kcov_size; 1508 1509 /* Buffer for coverage collection: */ 1510 void *kcov_area; 1511 1512 /* KCOV descriptor wired with this task or NULL: */ 1513 struct kcov *kcov; 1514 1515 /* KCOV common handle for remote coverage collection: */ 1516 u64 kcov_handle; 1517 1518 /* KCOV sequence number: */ 1519 int kcov_sequence; 1520 1521 /* Collect coverage from softirq context: */ 1522 unsigned int kcov_softirq; 1523 #endif 1524 1525 #ifdef CONFIG_MEMCG_V1 1526 struct mem_cgroup *memcg_in_oom; 1527 #endif 1528 1529 #ifdef CONFIG_MEMCG 1530 /* Number of pages to reclaim on returning to userland: */ 1531 unsigned int memcg_nr_pages_over_high; 1532 1533 /* Used by memcontrol for targeted memcg charge: */ 1534 struct mem_cgroup *active_memcg; 1535 1536 /* Cache for current->cgroups->memcg->objcg lookups: */ 1537 struct obj_cgroup *objcg; 1538 #endif 1539 1540 #ifdef CONFIG_BLK_CGROUP 1541 struct gendisk *throttle_disk; 1542 #endif 1543 1544 #ifdef CONFIG_UPROBES 1545 struct uprobe_task *utask; 1546 #endif 1547 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1548 unsigned int sequential_io; 1549 unsigned int sequential_io_avg; 1550 #endif 1551 struct kmap_ctrl kmap_ctrl; 1552 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1553 unsigned long task_state_change; 1554 # ifdef CONFIG_PREEMPT_RT 1555 unsigned long saved_state_change; 1556 # endif 1557 #endif 1558 struct rcu_head rcu; 1559 refcount_t rcu_users; 1560 int pagefault_disabled; 1561 #ifdef CONFIG_MMU 1562 struct task_struct *oom_reaper_list; 1563 struct timer_list oom_reaper_timer; 1564 #endif 1565 #ifdef CONFIG_VMAP_STACK 1566 struct vm_struct *stack_vm_area; 1567 #endif 1568 #ifdef CONFIG_THREAD_INFO_IN_TASK 1569 /* A live task holds one reference: */ 1570 refcount_t stack_refcount; 1571 #endif 1572 #ifdef CONFIG_LIVEPATCH 1573 int patch_state; 1574 #endif 1575 #ifdef CONFIG_SECURITY 1576 /* Used by LSM modules for access restriction: */ 1577 void *security; 1578 #endif 1579 #ifdef CONFIG_BPF_SYSCALL 1580 /* Used by BPF task local storage */ 1581 struct bpf_local_storage __rcu *bpf_storage; 1582 /* Used for BPF run context */ 1583 struct bpf_run_ctx *bpf_ctx; 1584 #endif 1585 /* Used by BPF for per-TASK xdp storage */ 1586 struct bpf_net_context *bpf_net_context; 1587 1588 #ifdef CONFIG_KSTACK_ERASE 1589 unsigned long lowest_stack; 1590 #endif 1591 #ifdef CONFIG_KSTACK_ERASE_METRICS 1592 unsigned long prev_lowest_stack; 1593 #endif 1594 1595 #ifdef CONFIG_X86_MCE 1596 void __user *mce_vaddr; 1597 __u64 mce_kflags; 1598 u64 mce_addr; 1599 __u64 mce_ripv : 1, 1600 mce_whole_page : 1, 1601 __mce_reserved : 62; 1602 struct callback_head mce_kill_me; 1603 int mce_count; 1604 #endif 1605 1606 #ifdef CONFIG_KRETPROBES 1607 struct llist_head kretprobe_instances; 1608 #endif 1609 #ifdef CONFIG_RETHOOK 1610 struct llist_head rethooks; 1611 #endif 1612 1613 #ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH 1614 /* 1615 * If L1D flush is supported on mm context switch 1616 * then we use this callback head to queue kill work 1617 * to kill tasks that are not running on SMT disabled 1618 * cores 1619 */ 1620 struct callback_head l1d_flush_kill; 1621 #endif 1622 1623 #ifdef CONFIG_RV 1624 /* 1625 * Per-task RV monitor, fixed in CONFIG_RV_PER_TASK_MONITORS. 1626 * If memory becomes a concern, we can think about a dynamic method. 1627 */ 1628 union rv_task_monitor rv[CONFIG_RV_PER_TASK_MONITORS]; 1629 #endif 1630 1631 #ifdef CONFIG_USER_EVENTS 1632 struct user_event_mm *user_event_mm; 1633 #endif 1634 1635 #ifdef CONFIG_UNWIND_USER 1636 struct unwind_task_info unwind_info; 1637 #endif 1638 1639 /* CPU-specific state of this task: */ 1640 struct thread_struct thread; 1641 1642 /* 1643 * New fields for task_struct should be added above here, so that 1644 * they are included in the randomized portion of task_struct. 1645 */ 1646 randomized_struct_fields_end 1647 } __attribute__ ((aligned (64))); 1648 1649 #ifdef CONFIG_SCHED_PROXY_EXEC 1650 DECLARE_STATIC_KEY_TRUE(__sched_proxy_exec); 1651 static inline bool sched_proxy_exec(void) 1652 { 1653 return static_branch_likely(&__sched_proxy_exec); 1654 } 1655 #else 1656 static inline bool sched_proxy_exec(void) 1657 { 1658 return false; 1659 } 1660 #endif 1661 1662 #define TASK_REPORT_IDLE (TASK_REPORT + 1) 1663 #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1) 1664 1665 static inline unsigned int __task_state_index(unsigned int tsk_state, 1666 unsigned int tsk_exit_state) 1667 { 1668 unsigned int state = (tsk_state | tsk_exit_state) & TASK_REPORT; 1669 1670 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX); 1671 1672 if ((tsk_state & TASK_IDLE) == TASK_IDLE) 1673 state = TASK_REPORT_IDLE; 1674 1675 /* 1676 * We're lying here, but rather than expose a completely new task state 1677 * to userspace, we can make this appear as if the task has gone through 1678 * a regular rt_mutex_lock() call. 1679 * Report frozen tasks as uninterruptible. 1680 */ 1681 if ((tsk_state & TASK_RTLOCK_WAIT) || (tsk_state & TASK_FROZEN)) 1682 state = TASK_UNINTERRUPTIBLE; 1683 1684 return fls(state); 1685 } 1686 1687 static inline unsigned int task_state_index(struct task_struct *tsk) 1688 { 1689 return __task_state_index(READ_ONCE(tsk->__state), tsk->exit_state); 1690 } 1691 1692 static inline char task_index_to_char(unsigned int state) 1693 { 1694 static const char state_char[] = "RSDTtXZPI"; 1695 1696 BUILD_BUG_ON(TASK_REPORT_MAX * 2 != 1 << (sizeof(state_char) - 1)); 1697 1698 return state_char[state]; 1699 } 1700 1701 static inline char task_state_to_char(struct task_struct *tsk) 1702 { 1703 return task_index_to_char(task_state_index(tsk)); 1704 } 1705 1706 #ifdef CONFIG_ARCH_HAS_LAZY_MMU_MODE 1707 /** 1708 * __task_lazy_mmu_mode_active() - Test the lazy MMU mode state for a task. 1709 * @tsk: The task to check. 1710 * 1711 * Test whether @tsk has its lazy MMU mode state set to active (i.e. enabled 1712 * and not paused). 1713 * 1714 * This function only considers the state saved in task_struct; to test whether 1715 * current actually is in lazy MMU mode, is_lazy_mmu_mode_active() should be 1716 * used instead. 1717 * 1718 * This function is intended for architectures that implement the lazy MMU 1719 * mode; it must not be called from generic code. 1720 */ 1721 static inline bool __task_lazy_mmu_mode_active(struct task_struct *tsk) 1722 { 1723 struct lazy_mmu_state *state = &tsk->lazy_mmu_state; 1724 1725 return state->enable_count > 0 && state->pause_count == 0; 1726 } 1727 1728 /** 1729 * is_lazy_mmu_mode_active() - Test whether we are currently in lazy MMU mode. 1730 * 1731 * Test whether the current context is in lazy MMU mode. This is true if both: 1732 * 1. We are not in interrupt context 1733 * 2. Lazy MMU mode is active for the current task 1734 * 1735 * This function is intended for architectures that implement the lazy MMU 1736 * mode; it must not be called from generic code. 1737 */ 1738 static inline bool is_lazy_mmu_mode_active(void) 1739 { 1740 if (in_interrupt()) 1741 return false; 1742 1743 return __task_lazy_mmu_mode_active(current); 1744 } 1745 #endif 1746 1747 extern struct pid *cad_pid; 1748 1749 /* 1750 * Per process flags 1751 */ 1752 #define PF_VCPU 0x00000001 /* I'm a virtual CPU */ 1753 #define PF_IDLE 0x00000002 /* I am an IDLE thread */ 1754 #define PF_EXITING 0x00000004 /* Getting shut down */ 1755 #define PF_POSTCOREDUMP 0x00000008 /* Coredumps should ignore this task */ 1756 #define PF_IO_WORKER 0x00000010 /* Task is an IO worker */ 1757 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 1758 #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */ 1759 #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */ 1760 #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */ 1761 #define PF_DUMPCORE 0x00000200 /* Dumped core */ 1762 #define PF_SIGNALED 0x00000400 /* Killed by a signal */ 1763 #define PF_MEMALLOC 0x00000800 /* Allocating memory to free memory. See memalloc_noreclaim_save() */ 1764 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */ 1765 #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */ 1766 #define PF_USER_WORKER 0x00004000 /* Kernel thread cloned from userspace thread */ 1767 #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */ 1768 #define PF_KCOMPACTD 0x00010000 /* I am kcompactd */ 1769 #define PF_KSWAPD 0x00020000 /* I am kswapd */ 1770 #define PF_MEMALLOC_NOFS 0x00040000 /* All allocations inherit GFP_NOFS. See memalloc_nfs_save() */ 1771 #define PF_MEMALLOC_NOIO 0x00080000 /* All allocations inherit GFP_NOIO. See memalloc_noio_save() */ 1772 #define PF_LOCAL_THROTTLE 0x00100000 /* Throttle writes only against the bdi I write to, 1773 * I am cleaning dirty pages from some other bdi. */ 1774 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 1775 #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */ 1776 #define PF__HOLE__00800000 0x00800000 1777 #define PF__HOLE__01000000 0x01000000 1778 #define PF__HOLE__02000000 0x02000000 1779 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */ 1780 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 1781 #define PF_MEMALLOC_PIN 0x10000000 /* Allocations constrained to zones which allow long term pinning. 1782 * See memalloc_pin_save() */ 1783 #define PF_BLOCK_TS 0x20000000 /* plug has ts that needs updating */ 1784 #define PF__HOLE__40000000 0x40000000 1785 #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */ 1786 1787 /* 1788 * Only the _current_ task can read/write to tsk->flags, but other 1789 * tasks can access tsk->flags in readonly mode for example 1790 * with tsk_used_math (like during threaded core dumping). 1791 * There is however an exception to this rule during ptrace 1792 * or during fork: the ptracer task is allowed to write to the 1793 * child->flags of its traced child (same goes for fork, the parent 1794 * can write to the child->flags), because we're guaranteed the 1795 * child is not running and in turn not changing child->flags 1796 * at the same time the parent does it. 1797 */ 1798 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1799 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1800 #define clear_used_math() clear_stopped_child_used_math(current) 1801 #define set_used_math() set_stopped_child_used_math(current) 1802 1803 #define conditional_stopped_child_used_math(condition, child) \ 1804 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1805 1806 #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current) 1807 1808 #define copy_to_stopped_child_used_math(child) \ 1809 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1810 1811 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1812 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1813 #define used_math() tsk_used_math(current) 1814 1815 static __always_inline bool is_percpu_thread(void) 1816 { 1817 return (current->flags & PF_NO_SETAFFINITY) && 1818 (current->nr_cpus_allowed == 1); 1819 } 1820 1821 static __always_inline bool is_user_task(struct task_struct *task) 1822 { 1823 return task->mm && !(task->flags & (PF_KTHREAD | PF_USER_WORKER)); 1824 } 1825 1826 /* Per-process atomic flags. */ 1827 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */ 1828 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */ 1829 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */ 1830 #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */ 1831 #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/ 1832 #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */ 1833 #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */ 1834 #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */ 1835 1836 #define TASK_PFA_TEST(name, func) \ 1837 static inline bool task_##func(struct task_struct *p) \ 1838 { return test_bit(PFA_##name, &p->atomic_flags); } 1839 1840 #define TASK_PFA_SET(name, func) \ 1841 static inline void task_set_##func(struct task_struct *p) \ 1842 { set_bit(PFA_##name, &p->atomic_flags); } 1843 1844 #define TASK_PFA_CLEAR(name, func) \ 1845 static inline void task_clear_##func(struct task_struct *p) \ 1846 { clear_bit(PFA_##name, &p->atomic_flags); } 1847 1848 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs) 1849 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs) 1850 1851 TASK_PFA_TEST(SPREAD_PAGE, spread_page) 1852 TASK_PFA_SET(SPREAD_PAGE, spread_page) 1853 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page) 1854 1855 TASK_PFA_TEST(SPREAD_SLAB, spread_slab) 1856 TASK_PFA_SET(SPREAD_SLAB, spread_slab) 1857 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab) 1858 1859 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable) 1860 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable) 1861 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable) 1862 1863 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1864 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1865 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1866 1867 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1868 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1869 1870 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable) 1871 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable) 1872 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable) 1873 1874 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1875 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1876 1877 static inline void 1878 current_restore_flags(unsigned long orig_flags, unsigned long flags) 1879 { 1880 current->flags &= ~flags; 1881 current->flags |= orig_flags & flags; 1882 } 1883 1884 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 1885 extern int task_can_attach(struct task_struct *p); 1886 extern int dl_bw_alloc(int cpu, u64 dl_bw); 1887 extern void dl_bw_free(int cpu, u64 dl_bw); 1888 1889 /* set_cpus_allowed_force() - consider using set_cpus_allowed_ptr() instead */ 1890 extern void set_cpus_allowed_force(struct task_struct *p, const struct cpumask *new_mask); 1891 1892 /** 1893 * set_cpus_allowed_ptr - set CPU affinity mask of a task 1894 * @p: the task 1895 * @new_mask: CPU affinity mask 1896 * 1897 * Return: zero if successful, or a negative error code 1898 */ 1899 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask); 1900 extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node); 1901 extern void release_user_cpus_ptr(struct task_struct *p); 1902 extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask); 1903 extern void force_compatible_cpus_allowed_ptr(struct task_struct *p); 1904 extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p); 1905 1906 extern int yield_to(struct task_struct *p, bool preempt); 1907 extern void set_user_nice(struct task_struct *p, long nice); 1908 extern int task_prio(const struct task_struct *p); 1909 1910 /** 1911 * task_nice - return the nice value of a given task. 1912 * @p: the task in question. 1913 * 1914 * Return: The nice value [ -20 ... 0 ... 19 ]. 1915 */ 1916 static inline int task_nice(const struct task_struct *p) 1917 { 1918 return PRIO_TO_NICE((p)->static_prio); 1919 } 1920 1921 extern int can_nice(const struct task_struct *p, const int nice); 1922 extern int task_curr(const struct task_struct *p); 1923 extern int idle_cpu(int cpu); 1924 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *); 1925 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *); 1926 extern void sched_set_fifo(struct task_struct *p); 1927 extern void sched_set_fifo_low(struct task_struct *p); 1928 extern void sched_set_fifo_secondary(struct task_struct *p); 1929 extern void sched_set_normal(struct task_struct *p, int nice); 1930 extern int sched_setattr(struct task_struct *, const struct sched_attr *); 1931 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *); 1932 extern struct task_struct *idle_task(int cpu); 1933 1934 /** 1935 * is_idle_task - is the specified task an idle task? 1936 * @p: the task in question. 1937 * 1938 * Return: 1 if @p is an idle task. 0 otherwise. 1939 */ 1940 static __always_inline bool is_idle_task(const struct task_struct *p) 1941 { 1942 return !!(p->flags & PF_IDLE); 1943 } 1944 1945 extern struct task_struct *curr_task(int cpu); 1946 extern void ia64_set_curr_task(int cpu, struct task_struct *p); 1947 1948 void yield(void); 1949 1950 union thread_union { 1951 struct task_struct task; 1952 #ifndef CONFIG_THREAD_INFO_IN_TASK 1953 struct thread_info thread_info; 1954 #endif 1955 unsigned long stack[THREAD_SIZE/sizeof(long)]; 1956 }; 1957 1958 #ifndef CONFIG_THREAD_INFO_IN_TASK 1959 extern struct thread_info init_thread_info; 1960 #endif 1961 1962 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)]; 1963 1964 #ifdef CONFIG_THREAD_INFO_IN_TASK 1965 # define task_thread_info(task) (&(task)->thread_info) 1966 #else 1967 # define task_thread_info(task) ((struct thread_info *)(task)->stack) 1968 #endif 1969 1970 /* 1971 * find a task by one of its numerical ids 1972 * 1973 * find_task_by_pid_ns(): 1974 * finds a task by its pid in the specified namespace 1975 * find_task_by_vpid(): 1976 * finds a task by its virtual pid 1977 * 1978 * see also find_vpid() etc in include/linux/pid.h 1979 */ 1980 1981 extern struct task_struct *find_task_by_vpid(pid_t nr); 1982 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns); 1983 1984 /* 1985 * find a task by its virtual pid and get the task struct 1986 */ 1987 extern struct task_struct *find_get_task_by_vpid(pid_t nr); 1988 1989 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 1990 extern int wake_up_process(struct task_struct *tsk); 1991 extern void wake_up_new_task(struct task_struct *tsk); 1992 1993 extern void kick_process(struct task_struct *tsk); 1994 1995 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); 1996 #define set_task_comm(tsk, from) ({ \ 1997 BUILD_BUG_ON(sizeof(from) != TASK_COMM_LEN); \ 1998 __set_task_comm(tsk, from, false); \ 1999 }) 2000 2001 /* 2002 * - Why not use task_lock()? 2003 * User space can randomly change their names anyway, so locking for readers 2004 * doesn't make sense. For writers, locking is probably necessary, as a race 2005 * condition could lead to long-term mixed results. 2006 * The strscpy_pad() in __set_task_comm() can ensure that the task comm is 2007 * always NUL-terminated and zero-padded. Therefore the race condition between 2008 * reader and writer is not an issue. 2009 * 2010 * - BUILD_BUG_ON() can help prevent the buf from being truncated. 2011 * Since the callers don't perform any return value checks, this safeguard is 2012 * necessary. 2013 */ 2014 #define get_task_comm(buf, tsk) ({ \ 2015 BUILD_BUG_ON(sizeof(buf) < TASK_COMM_LEN); \ 2016 strscpy_pad(buf, (tsk)->comm); \ 2017 buf; \ 2018 }) 2019 2020 static __always_inline void scheduler_ipi(void) 2021 { 2022 /* 2023 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting 2024 * TIF_NEED_RESCHED remotely (for the first time) will also send 2025 * this IPI. 2026 */ 2027 preempt_fold_need_resched(); 2028 } 2029 2030 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state); 2031 2032 /* 2033 * Set thread flags in other task's structures. 2034 * See asm/thread_info.h for TIF_xxxx flags available: 2035 */ 2036 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 2037 { 2038 set_ti_thread_flag(task_thread_info(tsk), flag); 2039 } 2040 2041 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2042 { 2043 clear_ti_thread_flag(task_thread_info(tsk), flag); 2044 } 2045 2046 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag, 2047 bool value) 2048 { 2049 update_ti_thread_flag(task_thread_info(tsk), flag, value); 2050 } 2051 2052 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 2053 { 2054 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 2055 } 2056 2057 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2058 { 2059 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 2060 } 2061 2062 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 2063 { 2064 return test_ti_thread_flag(task_thread_info(tsk), flag); 2065 } 2066 2067 static inline void set_tsk_need_resched(struct task_struct *tsk) 2068 { 2069 if (tracepoint_enabled(sched_set_need_resched_tp) && 2070 !test_tsk_thread_flag(tsk, TIF_NEED_RESCHED)) 2071 __trace_set_need_resched(tsk, TIF_NEED_RESCHED); 2072 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2073 } 2074 2075 static inline void clear_tsk_need_resched(struct task_struct *tsk) 2076 { 2077 atomic_long_andnot(_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY, 2078 (atomic_long_t *)&task_thread_info(tsk)->flags); 2079 } 2080 2081 static inline int test_tsk_need_resched(struct task_struct *tsk) 2082 { 2083 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 2084 } 2085 2086 static inline void set_need_resched_current(void) 2087 { 2088 lockdep_assert_irqs_disabled(); 2089 set_tsk_need_resched(current); 2090 set_preempt_need_resched(); 2091 } 2092 2093 /* 2094 * cond_resched() and cond_resched_lock(): latency reduction via 2095 * explicit rescheduling in places that are safe. The return 2096 * value indicates whether a reschedule was done in fact. 2097 * cond_resched_lock() will drop the spinlock before scheduling, 2098 */ 2099 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) 2100 extern int __cond_resched(void); 2101 2102 #if defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL) 2103 2104 DECLARE_STATIC_CALL(cond_resched, __cond_resched); 2105 2106 static __always_inline int _cond_resched(void) 2107 { 2108 return static_call_mod(cond_resched)(); 2109 } 2110 2111 #elif defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY) 2112 2113 extern int dynamic_cond_resched(void); 2114 2115 static __always_inline int _cond_resched(void) 2116 { 2117 return dynamic_cond_resched(); 2118 } 2119 2120 #else /* !CONFIG_PREEMPTION */ 2121 2122 static inline int _cond_resched(void) 2123 { 2124 return __cond_resched(); 2125 } 2126 2127 #endif /* PREEMPT_DYNAMIC && CONFIG_HAVE_PREEMPT_DYNAMIC_CALL */ 2128 2129 #else /* CONFIG_PREEMPTION && !CONFIG_PREEMPT_DYNAMIC */ 2130 2131 static inline int _cond_resched(void) 2132 { 2133 return 0; 2134 } 2135 2136 #endif /* !CONFIG_PREEMPTION || CONFIG_PREEMPT_DYNAMIC */ 2137 2138 #define cond_resched() ({ \ 2139 __might_resched(__FILE__, __LINE__, 0); \ 2140 _cond_resched(); \ 2141 }) 2142 2143 extern int __cond_resched_lock(spinlock_t *lock) __must_hold(lock); 2144 extern int __cond_resched_rwlock_read(rwlock_t *lock) __must_hold_shared(lock); 2145 extern int __cond_resched_rwlock_write(rwlock_t *lock) __must_hold(lock); 2146 2147 #define MIGHT_RESCHED_RCU_SHIFT 8 2148 #define MIGHT_RESCHED_PREEMPT_MASK ((1U << MIGHT_RESCHED_RCU_SHIFT) - 1) 2149 2150 #ifndef CONFIG_PREEMPT_RT 2151 /* 2152 * Non RT kernels have an elevated preempt count due to the held lock, 2153 * but are not allowed to be inside a RCU read side critical section 2154 */ 2155 # define PREEMPT_LOCK_RESCHED_OFFSETS PREEMPT_LOCK_OFFSET 2156 #else 2157 /* 2158 * spin/rw_lock() on RT implies rcu_read_lock(). The might_sleep() check in 2159 * cond_resched*lock() has to take that into account because it checks for 2160 * preempt_count() and rcu_preempt_depth(). 2161 */ 2162 # define PREEMPT_LOCK_RESCHED_OFFSETS \ 2163 (PREEMPT_LOCK_OFFSET + (1U << MIGHT_RESCHED_RCU_SHIFT)) 2164 #endif 2165 2166 #define cond_resched_lock(lock) ({ \ 2167 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ 2168 __cond_resched_lock(lock); \ 2169 }) 2170 2171 #define cond_resched_rwlock_read(lock) ({ \ 2172 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ 2173 __cond_resched_rwlock_read(lock); \ 2174 }) 2175 2176 #define cond_resched_rwlock_write(lock) ({ \ 2177 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ 2178 __cond_resched_rwlock_write(lock); \ 2179 }) 2180 2181 #ifndef CONFIG_PREEMPT_RT 2182 static inline struct mutex *__get_task_blocked_on(struct task_struct *p) 2183 { 2184 struct mutex *m = p->blocked_on; 2185 2186 if (m) 2187 lockdep_assert_held_once(&m->wait_lock); 2188 return m; 2189 } 2190 2191 static inline void __set_task_blocked_on(struct task_struct *p, struct mutex *m) 2192 { 2193 struct mutex *blocked_on = READ_ONCE(p->blocked_on); 2194 2195 WARN_ON_ONCE(!m); 2196 /* The task should only be setting itself as blocked */ 2197 WARN_ON_ONCE(p != current); 2198 /* Currently we serialize blocked_on under the mutex::wait_lock */ 2199 lockdep_assert_held_once(&m->wait_lock); 2200 /* 2201 * Check ensure we don't overwrite existing mutex value 2202 * with a different mutex. Note, setting it to the same 2203 * lock repeatedly is ok. 2204 */ 2205 WARN_ON_ONCE(blocked_on && blocked_on != m); 2206 WRITE_ONCE(p->blocked_on, m); 2207 } 2208 2209 static inline void set_task_blocked_on(struct task_struct *p, struct mutex *m) 2210 { 2211 guard(raw_spinlock_irqsave)(&m->wait_lock); 2212 __set_task_blocked_on(p, m); 2213 } 2214 2215 static inline void __clear_task_blocked_on(struct task_struct *p, struct mutex *m) 2216 { 2217 if (m) { 2218 struct mutex *blocked_on = READ_ONCE(p->blocked_on); 2219 2220 /* Currently we serialize blocked_on under the mutex::wait_lock */ 2221 lockdep_assert_held_once(&m->wait_lock); 2222 /* 2223 * There may be cases where we re-clear already cleared 2224 * blocked_on relationships, but make sure we are not 2225 * clearing the relationship with a different lock. 2226 */ 2227 WARN_ON_ONCE(blocked_on && blocked_on != m); 2228 } 2229 WRITE_ONCE(p->blocked_on, NULL); 2230 } 2231 2232 static inline void clear_task_blocked_on(struct task_struct *p, struct mutex *m) 2233 { 2234 guard(raw_spinlock_irqsave)(&m->wait_lock); 2235 __clear_task_blocked_on(p, m); 2236 } 2237 #else 2238 static inline void __clear_task_blocked_on(struct task_struct *p, struct rt_mutex *m) 2239 { 2240 } 2241 2242 static inline void clear_task_blocked_on(struct task_struct *p, struct rt_mutex *m) 2243 { 2244 } 2245 #endif /* !CONFIG_PREEMPT_RT */ 2246 2247 static __always_inline bool need_resched(void) 2248 { 2249 return unlikely(tif_need_resched()); 2250 } 2251 2252 /* 2253 * Wrappers for p->thread_info->cpu access. No-op on UP. 2254 */ 2255 #ifdef CONFIG_SMP 2256 2257 static inline unsigned int task_cpu(const struct task_struct *p) 2258 { 2259 return READ_ONCE(task_thread_info(p)->cpu); 2260 } 2261 2262 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 2263 2264 #else 2265 2266 static inline unsigned int task_cpu(const struct task_struct *p) 2267 { 2268 return 0; 2269 } 2270 2271 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 2272 { 2273 } 2274 2275 #endif /* CONFIG_SMP */ 2276 2277 static inline bool task_is_runnable(struct task_struct *p) 2278 { 2279 return p->on_rq && !p->se.sched_delayed; 2280 } 2281 2282 extern bool sched_task_on_rq(struct task_struct *p); 2283 extern unsigned long get_wchan(struct task_struct *p); 2284 extern struct task_struct *cpu_curr_snapshot(int cpu); 2285 2286 /* 2287 * In order to reduce various lock holder preemption latencies provide an 2288 * interface to see if a vCPU is currently running or not. 2289 * 2290 * This allows us to terminate optimistic spin loops and block, analogous to 2291 * the native optimistic spin heuristic of testing if the lock owner task is 2292 * running or not. 2293 */ 2294 #ifndef vcpu_is_preempted 2295 static inline bool vcpu_is_preempted(int cpu) 2296 { 2297 return false; 2298 } 2299 #endif 2300 2301 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 2302 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 2303 2304 #ifndef TASK_SIZE_OF 2305 #define TASK_SIZE_OF(tsk) TASK_SIZE 2306 #endif 2307 2308 static inline bool owner_on_cpu(struct task_struct *owner) 2309 { 2310 /* 2311 * As lock holder preemption issue, we both skip spinning if 2312 * task is not on cpu or its cpu is preempted 2313 */ 2314 return READ_ONCE(owner->on_cpu) && !vcpu_is_preempted(task_cpu(owner)); 2315 } 2316 2317 /* Returns effective CPU energy utilization, as seen by the scheduler */ 2318 unsigned long sched_cpu_util(int cpu); 2319 2320 #ifdef CONFIG_SCHED_CORE 2321 extern void sched_core_free(struct task_struct *tsk); 2322 extern void sched_core_fork(struct task_struct *p); 2323 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type, 2324 unsigned long uaddr); 2325 extern int sched_core_idle_cpu(int cpu); 2326 #else 2327 static inline void sched_core_free(struct task_struct *tsk) { } 2328 static inline void sched_core_fork(struct task_struct *p) { } 2329 static inline int sched_core_idle_cpu(int cpu) { return idle_cpu(cpu); } 2330 #endif 2331 2332 extern void sched_set_stop_task(int cpu, struct task_struct *stop); 2333 2334 #ifdef CONFIG_MEM_ALLOC_PROFILING 2335 static __always_inline struct alloc_tag *alloc_tag_save(struct alloc_tag *tag) 2336 { 2337 swap(current->alloc_tag, tag); 2338 return tag; 2339 } 2340 2341 static __always_inline void alloc_tag_restore(struct alloc_tag *tag, struct alloc_tag *old) 2342 { 2343 #ifdef CONFIG_MEM_ALLOC_PROFILING_DEBUG 2344 WARN(current->alloc_tag != tag, "current->alloc_tag was changed:\n"); 2345 #endif 2346 current->alloc_tag = old; 2347 } 2348 #else 2349 #define alloc_tag_save(_tag) NULL 2350 #define alloc_tag_restore(_tag, _old) do {} while (0) 2351 #endif 2352 2353 /* Avoids recursive inclusion hell */ 2354 #ifdef CONFIG_SCHED_MM_CID 2355 void sched_mm_cid_before_execve(struct task_struct *t); 2356 void sched_mm_cid_after_execve(struct task_struct *t); 2357 void sched_mm_cid_exit(struct task_struct *t); 2358 static __always_inline int task_mm_cid(struct task_struct *t) 2359 { 2360 return t->mm_cid.cid & ~(MM_CID_ONCPU | MM_CID_TRANSIT); 2361 } 2362 #else 2363 static inline void sched_mm_cid_before_execve(struct task_struct *t) { } 2364 static inline void sched_mm_cid_after_execve(struct task_struct *t) { } 2365 static inline void sched_mm_cid_exit(struct task_struct *t) { } 2366 static __always_inline int task_mm_cid(struct task_struct *t) 2367 { 2368 /* 2369 * Use the processor id as a fall-back when the mm cid feature is 2370 * disabled. This provides functional per-cpu data structure accesses 2371 * in user-space, althrough it won't provide the memory usage benefits. 2372 */ 2373 return task_cpu(t); 2374 } 2375 #endif 2376 2377 #ifndef MODULE 2378 #ifndef COMPILE_OFFSETS 2379 2380 extern void ___migrate_enable(void); 2381 2382 struct rq; 2383 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); 2384 2385 /* 2386 * The "struct rq" is not available here, so we can't access the 2387 * "runqueues" with this_cpu_ptr(), as the compilation will fail in 2388 * this_cpu_ptr() -> raw_cpu_ptr() -> __verify_pcpu_ptr(): 2389 * typeof((ptr) + 0) 2390 * 2391 * So use arch_raw_cpu_ptr()/PERCPU_PTR() directly here. 2392 */ 2393 #ifdef CONFIG_SMP 2394 #define this_rq_raw() arch_raw_cpu_ptr(&runqueues) 2395 #else 2396 #define this_rq_raw() PERCPU_PTR(&runqueues) 2397 #endif 2398 #define this_rq_pinned() (*(unsigned int *)((void *)this_rq_raw() + RQ_nr_pinned)) 2399 2400 static inline void __migrate_enable(void) 2401 { 2402 struct task_struct *p = current; 2403 2404 #ifdef CONFIG_DEBUG_PREEMPT 2405 /* 2406 * Check both overflow from migrate_disable() and superfluous 2407 * migrate_enable(). 2408 */ 2409 if (WARN_ON_ONCE((s16)p->migration_disabled <= 0)) 2410 return; 2411 #endif 2412 2413 if (p->migration_disabled > 1) { 2414 p->migration_disabled--; 2415 return; 2416 } 2417 2418 /* 2419 * Ensure stop_task runs either before or after this, and that 2420 * __set_cpus_allowed_ptr(SCA_MIGRATE_ENABLE) doesn't schedule(). 2421 */ 2422 guard(preempt)(); 2423 if (unlikely(p->cpus_ptr != &p->cpus_mask)) 2424 ___migrate_enable(); 2425 /* 2426 * Mustn't clear migration_disabled() until cpus_ptr points back at the 2427 * regular cpus_mask, otherwise things that race (eg. 2428 * select_fallback_rq) get confused. 2429 */ 2430 barrier(); 2431 p->migration_disabled = 0; 2432 this_rq_pinned()--; 2433 } 2434 2435 static inline void __migrate_disable(void) 2436 { 2437 struct task_struct *p = current; 2438 2439 if (p->migration_disabled) { 2440 #ifdef CONFIG_DEBUG_PREEMPT 2441 /* 2442 *Warn about overflow half-way through the range. 2443 */ 2444 WARN_ON_ONCE((s16)p->migration_disabled < 0); 2445 #endif 2446 p->migration_disabled++; 2447 return; 2448 } 2449 2450 guard(preempt)(); 2451 this_rq_pinned()++; 2452 p->migration_disabled = 1; 2453 } 2454 #else /* !COMPILE_OFFSETS */ 2455 static inline void __migrate_disable(void) { } 2456 static inline void __migrate_enable(void) { } 2457 #endif /* !COMPILE_OFFSETS */ 2458 2459 /* 2460 * So that it is possible to not export the runqueues variable, define and 2461 * export migrate_enable/migrate_disable in kernel/sched/core.c too, and use 2462 * them for the modules. The macro "INSTANTIATE_EXPORTED_MIGRATE_DISABLE" will 2463 * be defined in kernel/sched/core.c. 2464 */ 2465 #ifndef INSTANTIATE_EXPORTED_MIGRATE_DISABLE 2466 static __always_inline void migrate_disable(void) 2467 { 2468 __migrate_disable(); 2469 } 2470 2471 static __always_inline void migrate_enable(void) 2472 { 2473 __migrate_enable(); 2474 } 2475 #else /* INSTANTIATE_EXPORTED_MIGRATE_DISABLE */ 2476 extern void migrate_disable(void); 2477 extern void migrate_enable(void); 2478 #endif /* INSTANTIATE_EXPORTED_MIGRATE_DISABLE */ 2479 2480 #else /* MODULE */ 2481 extern void migrate_disable(void); 2482 extern void migrate_enable(void); 2483 #endif /* MODULE */ 2484 2485 DEFINE_LOCK_GUARD_0(migrate, migrate_disable(), migrate_enable()) 2486 2487 #endif 2488