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 14 #include <linux/pid.h> 15 #include <linux/sem.h> 16 #include <linux/shm.h> 17 #include <linux/mutex.h> 18 #include <linux/plist.h> 19 #include <linux/hrtimer.h> 20 #include <linux/irqflags.h> 21 #include <linux/seccomp.h> 22 #include <linux/nodemask.h> 23 #include <linux/rcupdate.h> 24 #include <linux/refcount.h> 25 #include <linux/resource.h> 26 #include <linux/latencytop.h> 27 #include <linux/sched/prio.h> 28 #include <linux/sched/types.h> 29 #include <linux/signal_types.h> 30 #include <linux/syscall_user_dispatch.h> 31 #include <linux/mm_types_task.h> 32 #include <linux/task_io_accounting.h> 33 #include <linux/posix-timers.h> 34 #include <linux/rseq.h> 35 #include <linux/seqlock.h> 36 #include <linux/kcsan.h> 37 #include <linux/android_vendor.h> 38 #include <asm/kmap_size.h> 39 #include <linux/android_kabi.h> 40 41 /* task_struct member predeclarations (sorted alphabetically): */ 42 struct audit_context; 43 struct backing_dev_info; 44 struct bio_list; 45 struct blk_plug; 46 struct bpf_local_storage; 47 struct bpf_run_ctx; 48 struct capture_control; 49 struct cfs_rq; 50 struct fs_struct; 51 struct futex_pi_state; 52 struct io_context; 53 struct io_uring_task; 54 struct mempolicy; 55 struct nameidata; 56 struct nsproxy; 57 struct perf_event_context; 58 struct pid_namespace; 59 struct pipe_inode_info; 60 struct rcu_node; 61 struct reclaim_state; 62 struct robust_list_head; 63 struct root_domain; 64 struct rq; 65 struct sched_attr; 66 struct sched_param; 67 struct seq_file; 68 struct sighand_struct; 69 struct signal_struct; 70 struct task_delay_info; 71 struct task_group; 72 73 /* 74 * Task state bitmask. NOTE! These bits are also 75 * encoded in fs/proc/array.c: get_task_state(). 76 * 77 * We have two separate sets of flags: task->state 78 * is about runnability, while task->exit_state are 79 * about the task exiting. Confusing, but this way 80 * modifying one set can't modify the other one by 81 * mistake. 82 */ 83 84 /* Used in tsk->state: */ 85 #define TASK_RUNNING 0x0000 86 #define TASK_INTERRUPTIBLE 0x0001 87 #define TASK_UNINTERRUPTIBLE 0x0002 88 #define __TASK_STOPPED 0x0004 89 #define __TASK_TRACED 0x0008 90 /* Used in tsk->exit_state: */ 91 #define EXIT_DEAD 0x0010 92 #define EXIT_ZOMBIE 0x0020 93 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD) 94 /* Used in tsk->state again: */ 95 #define TASK_PARKED 0x0040 96 #define TASK_DEAD 0x0080 97 #define TASK_WAKEKILL 0x0100 98 #define TASK_WAKING 0x0200 99 #define TASK_NOLOAD 0x0400 100 #define TASK_NEW 0x0800 101 /* RT specific auxilliary flag to mark RT lock waiters */ 102 #define TASK_RTLOCK_WAIT 0x1000 103 #define TASK_STATE_MAX 0x2000 104 105 /* Convenience macros for the sake of set_current_state: */ 106 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 107 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 108 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED) 109 110 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD) 111 112 /* Convenience macros for the sake of wake_up(): */ 113 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 114 115 /* get_task_state(): */ 116 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 117 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 118 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \ 119 TASK_PARKED) 120 121 #define task_is_running(task) (READ_ONCE((task)->__state) == TASK_RUNNING) 122 123 #define task_is_traced(task) ((READ_ONCE(task->__state) & __TASK_TRACED) != 0) 124 125 #define task_is_stopped(task) ((READ_ONCE(task->__state) & __TASK_STOPPED) != 0) 126 127 #define task_is_stopped_or_traced(task) ((READ_ONCE(task->__state) & (__TASK_STOPPED | __TASK_TRACED)) != 0) 128 129 /* 130 * Special states are those that do not use the normal wait-loop pattern. See 131 * the comment with set_special_state(). 132 */ 133 #define is_special_task_state(state) \ 134 ((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD)) 135 136 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 137 # define debug_normal_state_change(state_value) \ 138 do { \ 139 WARN_ON_ONCE(is_special_task_state(state_value)); \ 140 current->task_state_change = _THIS_IP_; \ 141 } while (0) 142 143 # define debug_special_state_change(state_value) \ 144 do { \ 145 WARN_ON_ONCE(!is_special_task_state(state_value)); \ 146 current->task_state_change = _THIS_IP_; \ 147 } while (0) 148 149 # define debug_rtlock_wait_set_state() \ 150 do { \ 151 current->saved_state_change = current->task_state_change;\ 152 current->task_state_change = _THIS_IP_; \ 153 } while (0) 154 155 # define debug_rtlock_wait_restore_state() \ 156 do { \ 157 current->task_state_change = current->saved_state_change;\ 158 } while (0) 159 160 #else 161 # define debug_normal_state_change(cond) do { } while (0) 162 # define debug_special_state_change(cond) do { } while (0) 163 # define debug_rtlock_wait_set_state() do { } while (0) 164 # define debug_rtlock_wait_restore_state() do { } while (0) 165 #endif 166 167 /* 168 * set_current_state() includes a barrier so that the write of current->state 169 * is correctly serialised wrt the caller's subsequent test of whether to 170 * actually sleep: 171 * 172 * for (;;) { 173 * set_current_state(TASK_UNINTERRUPTIBLE); 174 * if (CONDITION) 175 * break; 176 * 177 * schedule(); 178 * } 179 * __set_current_state(TASK_RUNNING); 180 * 181 * If the caller does not need such serialisation (because, for instance, the 182 * CONDITION test and condition change and wakeup are under the same lock) then 183 * use __set_current_state(). 184 * 185 * The above is typically ordered against the wakeup, which does: 186 * 187 * CONDITION = 1; 188 * wake_up_state(p, TASK_UNINTERRUPTIBLE); 189 * 190 * where wake_up_state()/try_to_wake_up() executes a full memory barrier before 191 * accessing p->state. 192 * 193 * Wakeup will do: if (@state & p->state) p->state = TASK_RUNNING, that is, 194 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a 195 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING). 196 * 197 * However, with slightly different timing the wakeup TASK_RUNNING store can 198 * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not 199 * a problem either because that will result in one extra go around the loop 200 * and our @cond test will save the day. 201 * 202 * Also see the comments of try_to_wake_up(). 203 */ 204 #define __set_current_state(state_value) \ 205 do { \ 206 debug_normal_state_change((state_value)); \ 207 WRITE_ONCE(current->__state, (state_value)); \ 208 } while (0) 209 210 #define set_current_state(state_value) \ 211 do { \ 212 debug_normal_state_change((state_value)); \ 213 smp_store_mb(current->__state, (state_value)); \ 214 } while (0) 215 216 /* 217 * set_special_state() should be used for those states when the blocking task 218 * can not use the regular condition based wait-loop. In that case we must 219 * serialize against wakeups such that any possible in-flight TASK_RUNNING 220 * stores will not collide with our state change. 221 */ 222 #define set_special_state(state_value) \ 223 do { \ 224 unsigned long flags; /* may shadow */ \ 225 \ 226 raw_spin_lock_irqsave(¤t->pi_lock, flags); \ 227 debug_special_state_change((state_value)); \ 228 WRITE_ONCE(current->__state, (state_value)); \ 229 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \ 230 } while (0) 231 232 /* 233 * PREEMPT_RT specific variants for "sleeping" spin/rwlocks 234 * 235 * RT's spin/rwlock substitutions are state preserving. The state of the 236 * task when blocking on the lock is saved in task_struct::saved_state and 237 * restored after the lock has been acquired. These operations are 238 * serialized by task_struct::pi_lock against try_to_wake_up(). Any non RT 239 * lock related wakeups while the task is blocked on the lock are 240 * redirected to operate on task_struct::saved_state to ensure that these 241 * are not dropped. On restore task_struct::saved_state is set to 242 * TASK_RUNNING so any wakeup attempt redirected to saved_state will fail. 243 * 244 * The lock operation looks like this: 245 * 246 * current_save_and_set_rtlock_wait_state(); 247 * for (;;) { 248 * if (try_lock()) 249 * break; 250 * raw_spin_unlock_irq(&lock->wait_lock); 251 * schedule_rtlock(); 252 * raw_spin_lock_irq(&lock->wait_lock); 253 * set_current_state(TASK_RTLOCK_WAIT); 254 * } 255 * current_restore_rtlock_saved_state(); 256 */ 257 #define current_save_and_set_rtlock_wait_state() \ 258 do { \ 259 lockdep_assert_irqs_disabled(); \ 260 raw_spin_lock(¤t->pi_lock); \ 261 current->saved_state = current->__state; \ 262 debug_rtlock_wait_set_state(); \ 263 WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT); \ 264 raw_spin_unlock(¤t->pi_lock); \ 265 } while (0); 266 267 #define current_restore_rtlock_saved_state() \ 268 do { \ 269 lockdep_assert_irqs_disabled(); \ 270 raw_spin_lock(¤t->pi_lock); \ 271 debug_rtlock_wait_restore_state(); \ 272 WRITE_ONCE(current->__state, current->saved_state); \ 273 current->saved_state = TASK_RUNNING; \ 274 raw_spin_unlock(¤t->pi_lock); \ 275 } while (0); 276 277 #define get_current_state() READ_ONCE(current->__state) 278 279 /* Task command name length: */ 280 #define TASK_COMM_LEN 16 281 282 extern void scheduler_tick(void); 283 284 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 285 286 extern long schedule_timeout(long timeout); 287 extern long schedule_timeout_interruptible(long timeout); 288 extern long schedule_timeout_killable(long timeout); 289 extern long schedule_timeout_uninterruptible(long timeout); 290 extern long schedule_timeout_idle(long timeout); 291 asmlinkage void schedule(void); 292 extern void schedule_preempt_disabled(void); 293 asmlinkage void preempt_schedule_irq(void); 294 #ifdef CONFIG_PREEMPT_RT 295 extern void schedule_rtlock(void); 296 #endif 297 298 extern int __must_check io_schedule_prepare(void); 299 extern void io_schedule_finish(int token); 300 extern long io_schedule_timeout(long timeout); 301 extern void io_schedule(void); 302 extern struct task_struct *pick_migrate_task(struct rq *rq); 303 extern int select_fallback_rq(int cpu, struct task_struct *p); 304 305 /** 306 * struct prev_cputime - snapshot of system and user cputime 307 * @utime: time spent in user mode 308 * @stime: time spent in system mode 309 * @lock: protects the above two fields 310 * 311 * Stores previous user/system time values such that we can guarantee 312 * monotonicity. 313 */ 314 struct prev_cputime { 315 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 316 u64 utime; 317 u64 stime; 318 raw_spinlock_t lock; 319 #endif 320 }; 321 322 enum vtime_state { 323 /* Task is sleeping or running in a CPU with VTIME inactive: */ 324 VTIME_INACTIVE = 0, 325 /* Task is idle */ 326 VTIME_IDLE, 327 /* Task runs in kernelspace in a CPU with VTIME active: */ 328 VTIME_SYS, 329 /* Task runs in userspace in a CPU with VTIME active: */ 330 VTIME_USER, 331 /* Task runs as guests in a CPU with VTIME active: */ 332 VTIME_GUEST, 333 }; 334 335 struct vtime { 336 seqcount_t seqcount; 337 unsigned long long starttime; 338 enum vtime_state state; 339 unsigned int cpu; 340 u64 utime; 341 u64 stime; 342 u64 gtime; 343 }; 344 345 /* 346 * Utilization clamp constraints. 347 * @UCLAMP_MIN: Minimum utilization 348 * @UCLAMP_MAX: Maximum utilization 349 * @UCLAMP_CNT: Utilization clamp constraints count 350 */ 351 enum uclamp_id { 352 UCLAMP_MIN = 0, 353 UCLAMP_MAX, 354 UCLAMP_CNT 355 }; 356 357 #ifdef CONFIG_SMP 358 extern struct root_domain def_root_domain; 359 extern struct mutex sched_domains_mutex; 360 #endif 361 362 struct sched_info { 363 #ifdef CONFIG_SCHED_INFO 364 /* Cumulative counters: */ 365 366 /* # of times we have run on this CPU: */ 367 unsigned long pcount; 368 369 /* Time spent waiting on a runqueue: */ 370 unsigned long long run_delay; 371 372 /* Timestamps: */ 373 374 /* When did we last run on a CPU? */ 375 unsigned long long last_arrival; 376 377 /* When were we last queued to run? */ 378 unsigned long long last_queued; 379 380 #endif /* CONFIG_SCHED_INFO */ 381 }; 382 383 /* 384 * Integer metrics need fixed point arithmetic, e.g., sched/fair 385 * has a few: load, load_avg, util_avg, freq, and capacity. 386 * 387 * We define a basic fixed point arithmetic range, and then formalize 388 * all these metrics based on that basic range. 389 */ 390 # define SCHED_FIXEDPOINT_SHIFT 10 391 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT) 392 393 /* Increase resolution of cpu_capacity calculations */ 394 # define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT 395 # define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) 396 397 struct load_weight { 398 unsigned long weight; 399 u32 inv_weight; 400 }; 401 402 /** 403 * struct util_est - Estimation utilization of FAIR tasks 404 * @enqueued: instantaneous estimated utilization of a task/cpu 405 * @ewma: the Exponential Weighted Moving Average (EWMA) 406 * utilization of a task 407 * 408 * Support data structure to track an Exponential Weighted Moving Average 409 * (EWMA) of a FAIR task's utilization. New samples are added to the moving 410 * average each time a task completes an activation. Sample's weight is chosen 411 * so that the EWMA will be relatively insensitive to transient changes to the 412 * task's workload. 413 * 414 * The enqueued attribute has a slightly different meaning for tasks and cpus: 415 * - task: the task's util_avg at last task dequeue time 416 * - cfs_rq: the sum of util_est.enqueued for each RUNNABLE task on that CPU 417 * Thus, the util_est.enqueued of a task represents the contribution on the 418 * estimated utilization of the CPU where that task is currently enqueued. 419 * 420 * Only for tasks we track a moving average of the past instantaneous 421 * estimated utilization. This allows to absorb sporadic drops in utilization 422 * of an otherwise almost periodic task. 423 * 424 * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg 425 * updates. When a task is dequeued, its util_est should not be updated if its 426 * util_avg has not been updated in the meantime. 427 * This information is mapped into the MSB bit of util_est.enqueued at dequeue 428 * time. Since max value of util_est.enqueued for a task is 1024 (PELT util_avg 429 * for a task) it is safe to use MSB. 430 */ 431 struct util_est { 432 unsigned int enqueued; 433 unsigned int ewma; 434 #define UTIL_EST_WEIGHT_SHIFT 2 435 #define UTIL_AVG_UNCHANGED 0x80000000 436 } __attribute__((__aligned__(sizeof(u64)))); 437 438 /* 439 * The load/runnable/util_avg accumulates an infinite geometric series 440 * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c). 441 * 442 * [load_avg definition] 443 * 444 * load_avg = runnable% * scale_load_down(load) 445 * 446 * [runnable_avg definition] 447 * 448 * runnable_avg = runnable% * SCHED_CAPACITY_SCALE 449 * 450 * [util_avg definition] 451 * 452 * util_avg = running% * SCHED_CAPACITY_SCALE 453 * 454 * where runnable% is the time ratio that a sched_entity is runnable and 455 * running% the time ratio that a sched_entity is running. 456 * 457 * For cfs_rq, they are the aggregated values of all runnable and blocked 458 * sched_entities. 459 * 460 * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU 461 * capacity scaling. The scaling is done through the rq_clock_pelt that is used 462 * for computing those signals (see update_rq_clock_pelt()) 463 * 464 * N.B., the above ratios (runnable% and running%) themselves are in the 465 * range of [0, 1]. To do fixed point arithmetics, we therefore scale them 466 * to as large a range as necessary. This is for example reflected by 467 * util_avg's SCHED_CAPACITY_SCALE. 468 * 469 * [Overflow issue] 470 * 471 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities 472 * with the highest load (=88761), always runnable on a single cfs_rq, 473 * and should not overflow as the number already hits PID_MAX_LIMIT. 474 * 475 * For all other cases (including 32-bit kernels), struct load_weight's 476 * weight will overflow first before we do, because: 477 * 478 * Max(load_avg) <= Max(load.weight) 479 * 480 * Then it is the load_weight's responsibility to consider overflow 481 * issues. 482 */ 483 struct sched_avg { 484 u64 last_update_time; 485 u64 load_sum; 486 u64 runnable_sum; 487 u32 util_sum; 488 u32 period_contrib; 489 unsigned long load_avg; 490 unsigned long runnable_avg; 491 unsigned long util_avg; 492 struct util_est util_est; 493 } ____cacheline_aligned; 494 495 struct sched_statistics { 496 #ifdef CONFIG_SCHEDSTATS 497 u64 wait_start; 498 u64 wait_max; 499 u64 wait_count; 500 u64 wait_sum; 501 u64 iowait_count; 502 u64 iowait_sum; 503 504 u64 sleep_start; 505 u64 sleep_max; 506 s64 sum_sleep_runtime; 507 508 u64 block_start; 509 u64 block_max; 510 u64 exec_max; 511 u64 slice_max; 512 513 u64 nr_migrations_cold; 514 u64 nr_failed_migrations_affine; 515 u64 nr_failed_migrations_running; 516 u64 nr_failed_migrations_hot; 517 u64 nr_forced_migrations; 518 519 u64 nr_wakeups; 520 u64 nr_wakeups_sync; 521 u64 nr_wakeups_migrate; 522 u64 nr_wakeups_local; 523 u64 nr_wakeups_remote; 524 u64 nr_wakeups_affine; 525 u64 nr_wakeups_affine_attempts; 526 u64 nr_wakeups_passive; 527 u64 nr_wakeups_idle; 528 #endif 529 }; 530 531 struct sched_entity { 532 /* For load-balancing: */ 533 struct load_weight load; 534 struct rb_node run_node; 535 struct list_head group_node; 536 unsigned int on_rq; 537 538 u64 exec_start; 539 u64 sum_exec_runtime; 540 u64 vruntime; 541 u64 prev_sum_exec_runtime; 542 543 u64 nr_migrations; 544 545 struct sched_statistics statistics; 546 547 #ifdef CONFIG_FAIR_GROUP_SCHED 548 int depth; 549 struct sched_entity *parent; 550 /* rq on which this entity is (to be) queued: */ 551 struct cfs_rq *cfs_rq; 552 /* rq "owned" by this entity/group: */ 553 struct cfs_rq *my_q; 554 /* cached value of my_q->h_nr_running */ 555 unsigned long runnable_weight; 556 #endif 557 558 #ifdef CONFIG_SMP 559 /* 560 * Per entity load average tracking. 561 * 562 * Put into separate cache line so it does not 563 * collide with read-mostly values above. 564 */ 565 struct sched_avg avg; 566 #endif 567 568 ANDROID_KABI_RESERVE(1); 569 ANDROID_KABI_RESERVE(2); 570 ANDROID_KABI_RESERVE(3); 571 ANDROID_KABI_RESERVE(4); 572 }; 573 574 struct sched_rt_entity { 575 struct list_head run_list; 576 unsigned long timeout; 577 unsigned long watchdog_stamp; 578 unsigned int time_slice; 579 unsigned short on_rq; 580 unsigned short on_list; 581 582 struct sched_rt_entity *back; 583 #ifdef CONFIG_RT_GROUP_SCHED 584 struct sched_rt_entity *parent; 585 /* rq on which this entity is (to be) queued: */ 586 struct rt_rq *rt_rq; 587 /* rq "owned" by this entity/group: */ 588 struct rt_rq *my_q; 589 #endif 590 591 ANDROID_KABI_RESERVE(1); 592 ANDROID_KABI_RESERVE(2); 593 ANDROID_KABI_RESERVE(3); 594 ANDROID_KABI_RESERVE(4); 595 } __randomize_layout; 596 597 struct sched_dl_entity { 598 struct rb_node rb_node; 599 600 /* 601 * Original scheduling parameters. Copied here from sched_attr 602 * during sched_setattr(), they will remain the same until 603 * the next sched_setattr(). 604 */ 605 u64 dl_runtime; /* Maximum runtime for each instance */ 606 u64 dl_deadline; /* Relative deadline of each instance */ 607 u64 dl_period; /* Separation of two instances (period) */ 608 u64 dl_bw; /* dl_runtime / dl_period */ 609 u64 dl_density; /* dl_runtime / dl_deadline */ 610 611 /* 612 * Actual scheduling parameters. Initialized with the values above, 613 * they are continuously updated during task execution. Note that 614 * the remaining runtime could be < 0 in case we are in overrun. 615 */ 616 s64 runtime; /* Remaining runtime for this instance */ 617 u64 deadline; /* Absolute deadline for this instance */ 618 unsigned int flags; /* Specifying the scheduler behaviour */ 619 620 /* 621 * Some bool flags: 622 * 623 * @dl_throttled tells if we exhausted the runtime. If so, the 624 * task has to wait for a replenishment to be performed at the 625 * next firing of dl_timer. 626 * 627 * @dl_boosted tells if we are boosted due to DI. If so we are 628 * outside bandwidth enforcement mechanism (but only until we 629 * exit the critical section); 630 * 631 * @dl_yielded tells if task gave up the CPU before consuming 632 * all its available runtime during the last job. 633 * 634 * @dl_non_contending tells if the task is inactive while still 635 * contributing to the active utilization. In other words, it 636 * indicates if the inactive timer has been armed and its handler 637 * has not been executed yet. This flag is useful to avoid race 638 * conditions between the inactive timer handler and the wakeup 639 * code. 640 * 641 * @dl_overrun tells if the task asked to be informed about runtime 642 * overruns. 643 */ 644 unsigned int dl_throttled : 1; 645 unsigned int dl_yielded : 1; 646 unsigned int dl_non_contending : 1; 647 unsigned int dl_overrun : 1; 648 649 /* 650 * Bandwidth enforcement timer. Each -deadline task has its 651 * own bandwidth to be enforced, thus we need one timer per task. 652 */ 653 struct hrtimer dl_timer; 654 655 /* 656 * Inactive timer, responsible for decreasing the active utilization 657 * at the "0-lag time". When a -deadline task blocks, it contributes 658 * to GRUB's active utilization until the "0-lag time", hence a 659 * timer is needed to decrease the active utilization at the correct 660 * time. 661 */ 662 struct hrtimer inactive_timer; 663 664 #ifdef CONFIG_RT_MUTEXES 665 /* 666 * Priority Inheritance. When a DEADLINE scheduling entity is boosted 667 * pi_se points to the donor, otherwise points to the dl_se it belongs 668 * to (the original one/itself). 669 */ 670 struct sched_dl_entity *pi_se; 671 #endif 672 }; 673 674 #ifdef CONFIG_UCLAMP_TASK 675 /* Number of utilization clamp buckets (shorter alias) */ 676 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT 677 678 /* 679 * Utilization clamp for a scheduling entity 680 * @value: clamp value "assigned" to a se 681 * @bucket_id: bucket index corresponding to the "assigned" value 682 * @active: the se is currently refcounted in a rq's bucket 683 * @user_defined: the requested clamp value comes from user-space 684 * 685 * The bucket_id is the index of the clamp bucket matching the clamp value 686 * which is pre-computed and stored to avoid expensive integer divisions from 687 * the fast path. 688 * 689 * The active bit is set whenever a task has got an "effective" value assigned, 690 * which can be different from the clamp value "requested" from user-space. 691 * This allows to know a task is refcounted in the rq's bucket corresponding 692 * to the "effective" bucket_id. 693 * 694 * The user_defined bit is set whenever a task has got a task-specific clamp 695 * value requested from userspace, i.e. the system defaults apply to this task 696 * just as a restriction. This allows to relax default clamps when a less 697 * restrictive task-specific value has been requested, thus allowing to 698 * implement a "nice" semantic. For example, a task running with a 20% 699 * default boost can still drop its own boosting to 0%. 700 */ 701 struct uclamp_se { 702 unsigned int value : bits_per(SCHED_CAPACITY_SCALE); 703 unsigned int bucket_id : bits_per(UCLAMP_BUCKETS); 704 unsigned int active : 1; 705 unsigned int user_defined : 1; 706 }; 707 #endif /* CONFIG_UCLAMP_TASK */ 708 709 union rcu_special { 710 struct { 711 u8 blocked; 712 u8 need_qs; 713 u8 exp_hint; /* Hint for performance. */ 714 u8 need_mb; /* Readers need smp_mb(). */ 715 } b; /* Bits. */ 716 u32 s; /* Set of bits. */ 717 }; 718 719 enum perf_event_task_context { 720 perf_invalid_context = -1, 721 perf_hw_context = 0, 722 perf_sw_context, 723 perf_nr_task_contexts, 724 }; 725 726 struct wake_q_node { 727 struct wake_q_node *next; 728 }; 729 730 struct kmap_ctrl { 731 #ifdef CONFIG_KMAP_LOCAL 732 int idx; 733 pte_t pteval[KM_MAX_IDX]; 734 #endif 735 }; 736 737 struct task_struct { 738 #ifdef CONFIG_THREAD_INFO_IN_TASK 739 /* 740 * For reasons of header soup (see current_thread_info()), this 741 * must be the first element of task_struct. 742 */ 743 struct thread_info thread_info; 744 #endif 745 unsigned int __state; 746 747 #ifdef CONFIG_PREEMPT_RT 748 /* saved state for "spinlock sleepers" */ 749 unsigned int saved_state; 750 #endif 751 752 /* 753 * This begins the randomizable portion of task_struct. Only 754 * scheduling-critical items should be added above here. 755 */ 756 randomized_struct_fields_start 757 758 void *stack; 759 refcount_t usage; 760 /* Per task flags (PF_*), defined further below: */ 761 unsigned int flags; 762 unsigned int ptrace; 763 764 #ifdef CONFIG_SMP 765 int on_cpu; 766 struct __call_single_node wake_entry; 767 #ifdef CONFIG_THREAD_INFO_IN_TASK 768 /* Current CPU: */ 769 unsigned int cpu; 770 #endif 771 unsigned int wakee_flips; 772 unsigned long wakee_flip_decay_ts; 773 struct task_struct *last_wakee; 774 775 /* 776 * recent_used_cpu is initially set as the last CPU used by a task 777 * that wakes affine another task. Waker/wakee relationships can 778 * push tasks around a CPU where each wakeup moves to the next one. 779 * Tracking a recently used CPU allows a quick search for a recently 780 * used CPU that may be idle. 781 */ 782 int recent_used_cpu; 783 int wake_cpu; 784 #endif 785 int on_rq; 786 787 int prio; 788 int static_prio; 789 int normal_prio; 790 unsigned int rt_priority; 791 792 const struct sched_class *sched_class; 793 struct sched_entity se; 794 struct sched_rt_entity rt; 795 struct sched_dl_entity dl; 796 797 #ifdef CONFIG_SCHED_CORE 798 struct rb_node core_node; 799 unsigned long core_cookie; 800 unsigned int core_occupation; 801 #endif 802 803 #ifdef CONFIG_CGROUP_SCHED 804 struct task_group *sched_task_group; 805 #endif 806 807 #ifdef CONFIG_UCLAMP_TASK 808 /* 809 * Clamp values requested for a scheduling entity. 810 * Must be updated with task_rq_lock() held. 811 */ 812 struct uclamp_se uclamp_req[UCLAMP_CNT]; 813 /* 814 * Effective clamp values used for a scheduling entity. 815 * Must be updated with task_rq_lock() held. 816 */ 817 struct uclamp_se uclamp[UCLAMP_CNT]; 818 #endif 819 820 #ifdef CONFIG_PREEMPT_NOTIFIERS 821 /* List of struct preempt_notifier: */ 822 struct hlist_head preempt_notifiers; 823 #endif 824 825 #ifdef CONFIG_BLK_DEV_IO_TRACE 826 unsigned int btrace_seq; 827 #endif 828 829 unsigned int policy; 830 int nr_cpus_allowed; 831 const cpumask_t *cpus_ptr; 832 cpumask_t *user_cpus_ptr; 833 cpumask_t cpus_mask; 834 void *migration_pending; 835 #ifdef CONFIG_SMP 836 unsigned short migration_disabled; 837 #endif 838 unsigned short migration_flags; 839 840 #ifdef CONFIG_PREEMPT_RCU 841 int rcu_read_lock_nesting; 842 union rcu_special rcu_read_unlock_special; 843 struct list_head rcu_node_entry; 844 struct rcu_node *rcu_blocked_node; 845 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 846 847 #ifdef CONFIG_TASKS_RCU 848 unsigned long rcu_tasks_nvcsw; 849 u8 rcu_tasks_holdout; 850 u8 rcu_tasks_idx; 851 int rcu_tasks_idle_cpu; 852 struct list_head rcu_tasks_holdout_list; 853 #endif /* #ifdef CONFIG_TASKS_RCU */ 854 855 #ifdef CONFIG_TASKS_TRACE_RCU 856 int trc_reader_nesting; 857 int trc_ipi_to_cpu; 858 union rcu_special trc_reader_special; 859 bool trc_reader_checked; 860 struct list_head trc_holdout_list; 861 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */ 862 863 struct sched_info sched_info; 864 865 struct list_head tasks; 866 #ifdef CONFIG_SMP 867 struct plist_node pushable_tasks; 868 struct rb_node pushable_dl_tasks; 869 #endif 870 871 struct mm_struct *mm; 872 struct mm_struct *active_mm; 873 874 /* Per-thread vma caching: */ 875 struct vmacache vmacache; 876 877 #ifdef SPLIT_RSS_COUNTING 878 struct task_rss_stat rss_stat; 879 #endif 880 int exit_state; 881 int exit_code; 882 int exit_signal; 883 /* The signal sent when the parent dies: */ 884 int pdeath_signal; 885 /* JOBCTL_*, siglock protected: */ 886 unsigned long jobctl; 887 888 /* Used for emulating ABI behavior of previous Linux versions: */ 889 unsigned int personality; 890 891 /* Scheduler bits, serialized by scheduler locks: */ 892 unsigned sched_reset_on_fork:1; 893 unsigned sched_contributes_to_load:1; 894 unsigned sched_migrated:1; 895 #ifdef CONFIG_PSI 896 unsigned sched_psi_wake_requeue:1; 897 #endif 898 899 /* Force alignment to the next boundary: */ 900 unsigned :0; 901 902 /* Unserialized, strictly 'current' */ 903 904 /* 905 * This field must not be in the scheduler word above due to wakelist 906 * queueing no longer being serialized by p->on_cpu. However: 907 * 908 * p->XXX = X; ttwu() 909 * schedule() if (p->on_rq && ..) // false 910 * smp_mb__after_spinlock(); if (smp_load_acquire(&p->on_cpu) && //true 911 * deactivate_task() ttwu_queue_wakelist()) 912 * p->on_rq = 0; p->sched_remote_wakeup = Y; 913 * 914 * guarantees all stores of 'current' are visible before 915 * ->sched_remote_wakeup gets used, so it can be in this word. 916 */ 917 unsigned sched_remote_wakeup:1; 918 919 /* Bit to tell LSMs we're in execve(): */ 920 unsigned in_execve:1; 921 unsigned in_iowait:1; 922 #ifndef TIF_RESTORE_SIGMASK 923 unsigned restore_sigmask:1; 924 #endif 925 #ifdef CONFIG_MEMCG 926 unsigned in_user_fault:1; 927 #endif 928 #ifdef CONFIG_LRU_GEN 929 /* whether the LRU algorithm may apply to this access */ 930 unsigned in_lru_fault:1; 931 #endif 932 #ifdef CONFIG_COMPAT_BRK 933 unsigned brk_randomized:1; 934 #endif 935 #ifdef CONFIG_CGROUPS 936 /* disallow userland-initiated cgroup migration */ 937 unsigned no_cgroup_migration:1; 938 /* task is frozen/stopped (used by the cgroup freezer) */ 939 unsigned frozen:1; 940 #endif 941 #ifdef CONFIG_BLK_CGROUP 942 unsigned use_memdelay:1; 943 #endif 944 #ifdef CONFIG_PSI 945 /* Stalled due to lack of memory */ 946 unsigned in_memstall:1; 947 #endif 948 #ifdef CONFIG_PAGE_OWNER 949 /* Used by page_owner=on to detect recursion in page tracking. */ 950 unsigned in_page_owner:1; 951 #endif 952 #ifdef CONFIG_EVENTFD 953 /* Recursion prevention for eventfd_signal() */ 954 unsigned in_eventfd_signal:1; 955 #endif 956 957 unsigned long atomic_flags; /* Flags requiring atomic access. */ 958 959 struct restart_block restart_block; 960 961 pid_t pid; 962 pid_t tgid; 963 964 #ifdef CONFIG_STACKPROTECTOR 965 /* Canary value for the -fstack-protector GCC feature: */ 966 unsigned long stack_canary; 967 #endif 968 /* 969 * Pointers to the (original) parent process, youngest child, younger sibling, 970 * older sibling, respectively. (p->father can be replaced with 971 * p->real_parent->pid) 972 */ 973 974 /* Real parent process: */ 975 struct task_struct __rcu *real_parent; 976 977 /* Recipient of SIGCHLD, wait4() reports: */ 978 struct task_struct __rcu *parent; 979 980 /* 981 * Children/sibling form the list of natural children: 982 */ 983 struct list_head children; 984 struct list_head sibling; 985 struct task_struct *group_leader; 986 987 /* 988 * 'ptraced' is the list of tasks this task is using ptrace() on. 989 * 990 * This includes both natural children and PTRACE_ATTACH targets. 991 * 'ptrace_entry' is this task's link on the p->parent->ptraced list. 992 */ 993 struct list_head ptraced; 994 struct list_head ptrace_entry; 995 996 /* PID/PID hash table linkage. */ 997 struct pid *thread_pid; 998 struct hlist_node pid_links[PIDTYPE_MAX]; 999 struct list_head thread_group; 1000 struct list_head thread_node; 1001 1002 struct completion *vfork_done; 1003 1004 /* CLONE_CHILD_SETTID: */ 1005 int __user *set_child_tid; 1006 1007 /* CLONE_CHILD_CLEARTID: */ 1008 int __user *clear_child_tid; 1009 1010 /* PF_IO_WORKER */ 1011 void *pf_io_worker; 1012 1013 u64 utime; 1014 u64 stime; 1015 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME 1016 u64 utimescaled; 1017 u64 stimescaled; 1018 #endif 1019 u64 gtime; 1020 #ifdef CONFIG_CPU_FREQ_TIMES 1021 u64 *time_in_state; 1022 unsigned int max_state; 1023 #endif 1024 struct prev_cputime prev_cputime; 1025 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1026 struct vtime vtime; 1027 #endif 1028 1029 #ifdef CONFIG_NO_HZ_FULL 1030 atomic_t tick_dep_mask; 1031 #endif 1032 /* Context switch counts: */ 1033 unsigned long nvcsw; 1034 unsigned long nivcsw; 1035 1036 /* Monotonic time in nsecs: */ 1037 u64 start_time; 1038 1039 /* Boot based time in nsecs: */ 1040 u64 start_boottime; 1041 1042 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */ 1043 unsigned long min_flt; 1044 unsigned long maj_flt; 1045 1046 /* Empty if CONFIG_POSIX_CPUTIMERS=n */ 1047 struct posix_cputimers posix_cputimers; 1048 1049 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK 1050 struct posix_cputimers_work posix_cputimers_work; 1051 #endif 1052 1053 /* Process credentials: */ 1054 1055 /* Tracer's credentials at attach: */ 1056 const struct cred __rcu *ptracer_cred; 1057 1058 /* Objective and real subjective task credentials (COW): */ 1059 const struct cred __rcu *real_cred; 1060 1061 /* Effective (overridable) subjective task credentials (COW): */ 1062 const struct cred __rcu *cred; 1063 1064 #ifdef CONFIG_KEYS 1065 /* Cached requested key. */ 1066 struct key *cached_requested_key; 1067 #endif 1068 1069 /* 1070 * executable name, excluding path. 1071 * 1072 * - normally initialized setup_new_exec() 1073 * - access it with [gs]et_task_comm() 1074 * - lock it with task_lock() 1075 */ 1076 char comm[TASK_COMM_LEN]; 1077 1078 struct nameidata *nameidata; 1079 1080 #ifdef CONFIG_SYSVIPC 1081 struct sysv_sem sysvsem; 1082 struct sysv_shm sysvshm; 1083 #endif 1084 #ifdef CONFIG_DETECT_HUNG_TASK 1085 unsigned long last_switch_count; 1086 unsigned long last_switch_time; 1087 #endif 1088 /* Filesystem information: */ 1089 struct fs_struct *fs; 1090 1091 /* Open file information: */ 1092 struct files_struct *files; 1093 1094 #ifdef CONFIG_IO_URING 1095 struct io_uring_task *io_uring; 1096 #endif 1097 1098 /* Namespaces: */ 1099 struct nsproxy *nsproxy; 1100 1101 /* Signal handlers: */ 1102 struct signal_struct *signal; 1103 struct sighand_struct __rcu *sighand; 1104 sigset_t blocked; 1105 sigset_t real_blocked; 1106 /* Restored if set_restore_sigmask() was used: */ 1107 sigset_t saved_sigmask; 1108 struct sigpending pending; 1109 unsigned long sas_ss_sp; 1110 size_t sas_ss_size; 1111 unsigned int sas_ss_flags; 1112 1113 struct callback_head *task_works; 1114 1115 #ifdef CONFIG_AUDIT 1116 #ifdef CONFIG_AUDITSYSCALL 1117 struct audit_context *audit_context; 1118 #endif 1119 kuid_t loginuid; 1120 unsigned int sessionid; 1121 #endif 1122 struct seccomp seccomp; 1123 struct syscall_user_dispatch syscall_dispatch; 1124 1125 /* Thread group tracking: */ 1126 u64 parent_exec_id; 1127 u64 self_exec_id; 1128 1129 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */ 1130 spinlock_t alloc_lock; 1131 1132 /* Protection of the PI data structures: */ 1133 raw_spinlock_t pi_lock; 1134 1135 struct wake_q_node wake_q; 1136 int wake_q_count; 1137 1138 #ifdef CONFIG_RT_MUTEXES 1139 /* PI waiters blocked on a rt_mutex held by this task: */ 1140 struct rb_root_cached pi_waiters; 1141 /* Updated under owner's pi_lock and rq lock */ 1142 struct task_struct *pi_top_task; 1143 /* Deadlock detection and priority inheritance handling: */ 1144 struct rt_mutex_waiter *pi_blocked_on; 1145 #endif 1146 1147 #ifdef CONFIG_DEBUG_MUTEXES 1148 /* Mutex deadlock detection: */ 1149 struct mutex_waiter *blocked_on; 1150 #endif 1151 1152 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1153 int non_block_count; 1154 #endif 1155 1156 #ifdef CONFIG_TRACE_IRQFLAGS 1157 struct irqtrace_events irqtrace; 1158 unsigned int hardirq_threaded; 1159 u64 hardirq_chain_key; 1160 int softirqs_enabled; 1161 int softirq_context; 1162 int irq_config; 1163 #endif 1164 #ifdef CONFIG_PREEMPT_RT 1165 int softirq_disable_cnt; 1166 #endif 1167 1168 #ifdef CONFIG_LOCKDEP 1169 # define MAX_LOCK_DEPTH 48UL 1170 u64 curr_chain_key; 1171 int lockdep_depth; 1172 unsigned int lockdep_recursion; 1173 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1174 #endif 1175 1176 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP) 1177 unsigned int in_ubsan; 1178 #endif 1179 1180 /* Journalling filesystem info: */ 1181 void *journal_info; 1182 1183 /* Stacked block device info: */ 1184 struct bio_list *bio_list; 1185 1186 #ifdef CONFIG_BLOCK 1187 /* Stack plugging: */ 1188 struct blk_plug *plug; 1189 #endif 1190 1191 /* VM state: */ 1192 struct reclaim_state *reclaim_state; 1193 1194 struct backing_dev_info *backing_dev_info; 1195 1196 struct io_context *io_context; 1197 1198 #ifdef CONFIG_COMPACTION 1199 struct capture_control *capture_control; 1200 #endif 1201 /* Ptrace state: */ 1202 unsigned long ptrace_message; 1203 kernel_siginfo_t *last_siginfo; 1204 1205 struct task_io_accounting ioac; 1206 #ifdef CONFIG_PSI 1207 /* Pressure stall state */ 1208 unsigned int psi_flags; 1209 #endif 1210 #ifdef CONFIG_TASK_XACCT 1211 /* Accumulated RSS usage: */ 1212 u64 acct_rss_mem1; 1213 /* Accumulated virtual memory usage: */ 1214 u64 acct_vm_mem1; 1215 /* stime + utime since last update: */ 1216 u64 acct_timexpd; 1217 #endif 1218 #ifdef CONFIG_CPUSETS 1219 /* Protected by ->alloc_lock: */ 1220 nodemask_t mems_allowed; 1221 /* Sequence number to catch updates: */ 1222 seqcount_spinlock_t mems_allowed_seq; 1223 int cpuset_mem_spread_rotor; 1224 int cpuset_slab_spread_rotor; 1225 #endif 1226 #ifdef CONFIG_CGROUPS 1227 /* Control Group info protected by css_set_lock: */ 1228 struct css_set __rcu *cgroups; 1229 /* cg_list protected by css_set_lock and tsk->alloc_lock: */ 1230 struct list_head cg_list; 1231 #endif 1232 #ifdef CONFIG_X86_CPU_RESCTRL 1233 u32 closid; 1234 u32 rmid; 1235 #endif 1236 #ifdef CONFIG_FUTEX 1237 struct robust_list_head __user *robust_list; 1238 #ifdef CONFIG_COMPAT 1239 struct compat_robust_list_head __user *compat_robust_list; 1240 #endif 1241 struct list_head pi_state_list; 1242 struct futex_pi_state *pi_state_cache; 1243 struct mutex futex_exit_mutex; 1244 unsigned int futex_state; 1245 #endif 1246 #ifdef CONFIG_PERF_EVENTS 1247 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; 1248 struct mutex perf_event_mutex; 1249 struct list_head perf_event_list; 1250 #endif 1251 #ifdef CONFIG_DEBUG_PREEMPT 1252 unsigned long preempt_disable_ip; 1253 #endif 1254 #ifdef CONFIG_NUMA 1255 /* Protected by alloc_lock: */ 1256 struct mempolicy *mempolicy; 1257 short il_prev; 1258 short pref_node_fork; 1259 #endif 1260 #ifdef CONFIG_NUMA_BALANCING 1261 int numa_scan_seq; 1262 unsigned int numa_scan_period; 1263 unsigned int numa_scan_period_max; 1264 int numa_preferred_nid; 1265 unsigned long numa_migrate_retry; 1266 /* Migration stamp: */ 1267 u64 node_stamp; 1268 u64 last_task_numa_placement; 1269 u64 last_sum_exec_runtime; 1270 struct callback_head numa_work; 1271 1272 /* 1273 * This pointer is only modified for current in syscall and 1274 * pagefault context (and for tasks being destroyed), so it can be read 1275 * from any of the following contexts: 1276 * - RCU read-side critical section 1277 * - current->numa_group from everywhere 1278 * - task's runqueue locked, task not running 1279 */ 1280 struct numa_group __rcu *numa_group; 1281 1282 /* 1283 * numa_faults is an array split into four regions: 1284 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer 1285 * in this precise order. 1286 * 1287 * faults_memory: Exponential decaying average of faults on a per-node 1288 * basis. Scheduling placement decisions are made based on these 1289 * counts. The values remain static for the duration of a PTE scan. 1290 * faults_cpu: Track the nodes the process was running on when a NUMA 1291 * hinting fault was incurred. 1292 * faults_memory_buffer and faults_cpu_buffer: Record faults per node 1293 * during the current scan window. When the scan completes, the counts 1294 * in faults_memory and faults_cpu decay and these values are copied. 1295 */ 1296 unsigned long *numa_faults; 1297 unsigned long total_numa_faults; 1298 1299 /* 1300 * numa_faults_locality tracks if faults recorded during the last 1301 * scan window were remote/local or failed to migrate. The task scan 1302 * period is adapted based on the locality of the faults with different 1303 * weights depending on whether they were shared or private faults 1304 */ 1305 unsigned long numa_faults_locality[3]; 1306 1307 unsigned long numa_pages_migrated; 1308 #endif /* CONFIG_NUMA_BALANCING */ 1309 1310 #ifdef CONFIG_RSEQ 1311 struct rseq __user *rseq; 1312 u32 rseq_sig; 1313 /* 1314 * RmW on rseq_event_mask must be performed atomically 1315 * with respect to preemption. 1316 */ 1317 unsigned long rseq_event_mask; 1318 #endif 1319 1320 struct tlbflush_unmap_batch tlb_ubc; 1321 1322 union { 1323 refcount_t rcu_users; 1324 struct rcu_head rcu; 1325 }; 1326 1327 /* Cache last used pipe for splice(): */ 1328 struct pipe_inode_info *splice_pipe; 1329 1330 struct page_frag task_frag; 1331 1332 #ifdef CONFIG_TASK_DELAY_ACCT 1333 struct task_delay_info *delays; 1334 #endif 1335 1336 #ifdef CONFIG_FAULT_INJECTION 1337 int make_it_fail; 1338 unsigned int fail_nth; 1339 #endif 1340 /* 1341 * When (nr_dirtied >= nr_dirtied_pause), it's time to call 1342 * balance_dirty_pages() for a dirty throttling pause: 1343 */ 1344 int nr_dirtied; 1345 int nr_dirtied_pause; 1346 /* Start of a write-and-pause period: */ 1347 unsigned long dirty_paused_when; 1348 1349 #ifdef CONFIG_LATENCYTOP 1350 int latency_record_count; 1351 struct latency_record latency_record[LT_SAVECOUNT]; 1352 #endif 1353 /* 1354 * Time slack values; these are used to round up poll() and 1355 * select() etc timeout values. These are in nanoseconds. 1356 */ 1357 u64 timer_slack_ns; 1358 u64 default_timer_slack_ns; 1359 1360 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) 1361 unsigned int kasan_depth; 1362 #endif 1363 1364 #ifdef CONFIG_KCSAN 1365 struct kcsan_ctx kcsan_ctx; 1366 #ifdef CONFIG_TRACE_IRQFLAGS 1367 struct irqtrace_events kcsan_save_irqtrace; 1368 #endif 1369 #endif 1370 1371 struct kunit *kunit_test; 1372 1373 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1374 /* Index of current stored address in ret_stack: */ 1375 int curr_ret_stack; 1376 int curr_ret_depth; 1377 1378 /* Stack of return addresses for return function tracing: */ 1379 struct ftrace_ret_stack *ret_stack; 1380 1381 /* Timestamp for last schedule: */ 1382 unsigned long long ftrace_timestamp; 1383 1384 /* 1385 * Number of functions that haven't been traced 1386 * because of depth overrun: 1387 */ 1388 atomic_t trace_overrun; 1389 1390 /* Pause tracing: */ 1391 atomic_t tracing_graph_pause; 1392 #endif 1393 1394 #ifdef CONFIG_TRACING 1395 /* State flags for use by tracers: */ 1396 unsigned long trace; 1397 1398 /* Bitmask and counter of trace recursion: */ 1399 unsigned long trace_recursion; 1400 #endif /* CONFIG_TRACING */ 1401 1402 #ifdef CONFIG_KCOV 1403 /* See kernel/kcov.c for more details. */ 1404 1405 /* Coverage collection mode enabled for this task (0 if disabled): */ 1406 unsigned int kcov_mode; 1407 1408 /* Size of the kcov_area: */ 1409 unsigned int kcov_size; 1410 1411 /* Buffer for coverage collection: */ 1412 void *kcov_area; 1413 1414 /* KCOV descriptor wired with this task or NULL: */ 1415 struct kcov *kcov; 1416 1417 /* KCOV common handle for remote coverage collection: */ 1418 u64 kcov_handle; 1419 1420 /* KCOV sequence number: */ 1421 int kcov_sequence; 1422 1423 /* Collect coverage from softirq context: */ 1424 unsigned int kcov_softirq; 1425 #endif 1426 1427 #ifdef CONFIG_MEMCG 1428 struct mem_cgroup *memcg_in_oom; 1429 gfp_t memcg_oom_gfp_mask; 1430 int memcg_oom_order; 1431 1432 /* Number of pages to reclaim on returning to userland: */ 1433 unsigned int memcg_nr_pages_over_high; 1434 1435 /* Used by memcontrol for targeted memcg charge: */ 1436 struct mem_cgroup *active_memcg; 1437 #endif 1438 1439 #ifdef CONFIG_BLK_CGROUP 1440 struct request_queue *throttle_queue; 1441 #endif 1442 1443 #ifdef CONFIG_UPROBES 1444 struct uprobe_task *utask; 1445 #endif 1446 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1447 unsigned int sequential_io; 1448 unsigned int sequential_io_avg; 1449 #endif 1450 struct kmap_ctrl kmap_ctrl; 1451 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1452 unsigned long task_state_change; 1453 # ifdef CONFIG_PREEMPT_RT 1454 unsigned long saved_state_change; 1455 # endif 1456 #endif 1457 int pagefault_disabled; 1458 #ifdef CONFIG_MMU 1459 struct task_struct *oom_reaper_list; 1460 struct timer_list oom_reaper_timer; 1461 #endif 1462 #ifdef CONFIG_VMAP_STACK 1463 struct vm_struct *stack_vm_area; 1464 #endif 1465 #ifdef CONFIG_THREAD_INFO_IN_TASK 1466 /* A live task holds one reference: */ 1467 refcount_t stack_refcount; 1468 #endif 1469 #ifdef CONFIG_LIVEPATCH 1470 int patch_state; 1471 #endif 1472 #ifdef CONFIG_SECURITY 1473 /* Used by LSM modules for access restriction: */ 1474 void *security; 1475 #endif 1476 #ifdef CONFIG_BPF_SYSCALL 1477 /* Used by BPF task local storage */ 1478 struct bpf_local_storage __rcu *bpf_storage; 1479 /* Used for BPF run context */ 1480 struct bpf_run_ctx *bpf_ctx; 1481 #endif 1482 1483 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK 1484 unsigned long lowest_stack; 1485 unsigned long prev_lowest_stack; 1486 #endif 1487 1488 #ifdef CONFIG_X86_MCE 1489 void __user *mce_vaddr; 1490 __u64 mce_kflags; 1491 u64 mce_addr; 1492 __u64 mce_ripv : 1, 1493 mce_whole_page : 1, 1494 __mce_reserved : 62; 1495 struct callback_head mce_kill_me; 1496 int mce_count; 1497 #endif 1498 ANDROID_VENDOR_DATA_ARRAY(1, 64); 1499 ANDROID_OEM_DATA_ARRAY(1, 6); 1500 1501 #ifdef CONFIG_KRETPROBES 1502 struct llist_head kretprobe_instances; 1503 #endif 1504 1505 #ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH 1506 /* 1507 * If L1D flush is supported on mm context switch 1508 * then we use this callback head to queue kill work 1509 * to kill tasks that are not running on SMT disabled 1510 * cores 1511 */ 1512 struct callback_head l1d_flush_kill; 1513 #endif 1514 1515 ANDROID_KABI_RESERVE(1); 1516 ANDROID_KABI_RESERVE(2); 1517 ANDROID_KABI_RESERVE(3); 1518 ANDROID_KABI_RESERVE(4); 1519 ANDROID_KABI_RESERVE(5); 1520 ANDROID_KABI_RESERVE(6); 1521 ANDROID_KABI_RESERVE(7); 1522 ANDROID_KABI_RESERVE(8); 1523 1524 /* 1525 * New fields for task_struct should be added above here, so that 1526 * they are included in the randomized portion of task_struct. 1527 */ 1528 randomized_struct_fields_end 1529 1530 /* CPU-specific state of this task: */ 1531 struct thread_struct thread; 1532 1533 /* 1534 * WARNING: on x86, 'thread_struct' contains a variable-sized 1535 * structure. It *MUST* be at the end of 'task_struct'. 1536 * 1537 * Do not put anything below here! 1538 */ 1539 }; 1540 task_pid(struct task_struct * task)1541 static inline struct pid *task_pid(struct task_struct *task) 1542 { 1543 return task->thread_pid; 1544 } 1545 1546 /* 1547 * the helpers to get the task's different pids as they are seen 1548 * from various namespaces 1549 * 1550 * task_xid_nr() : global id, i.e. the id seen from the init namespace; 1551 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of 1552 * current. 1553 * task_xid_nr_ns() : id seen from the ns specified; 1554 * 1555 * see also pid_nr() etc in include/linux/pid.h 1556 */ 1557 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, struct pid_namespace *ns); 1558 task_pid_nr(struct task_struct * tsk)1559 static inline pid_t task_pid_nr(struct task_struct *tsk) 1560 { 1561 return tsk->pid; 1562 } 1563 task_pid_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1564 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) 1565 { 1566 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); 1567 } 1568 task_pid_vnr(struct task_struct * tsk)1569 static inline pid_t task_pid_vnr(struct task_struct *tsk) 1570 { 1571 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); 1572 } 1573 1574 task_tgid_nr(struct task_struct * tsk)1575 static inline pid_t task_tgid_nr(struct task_struct *tsk) 1576 { 1577 return tsk->tgid; 1578 } 1579 1580 /** 1581 * pid_alive - check that a task structure is not stale 1582 * @p: Task structure to be checked. 1583 * 1584 * Test if a process is not yet dead (at most zombie state) 1585 * If pid_alive fails, then pointers within the task structure 1586 * can be stale and must not be dereferenced. 1587 * 1588 * Return: 1 if the process is alive. 0 otherwise. 1589 */ pid_alive(const struct task_struct * p)1590 static inline int pid_alive(const struct task_struct *p) 1591 { 1592 return p->thread_pid != NULL; 1593 } 1594 task_pgrp_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1595 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) 1596 { 1597 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); 1598 } 1599 task_pgrp_vnr(struct task_struct * tsk)1600 static inline pid_t task_pgrp_vnr(struct task_struct *tsk) 1601 { 1602 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); 1603 } 1604 1605 task_session_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1606 static inline pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) 1607 { 1608 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); 1609 } 1610 task_session_vnr(struct task_struct * tsk)1611 static inline pid_t task_session_vnr(struct task_struct *tsk) 1612 { 1613 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); 1614 } 1615 task_tgid_nr_ns(struct task_struct * tsk,struct pid_namespace * ns)1616 static inline pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) 1617 { 1618 return __task_pid_nr_ns(tsk, PIDTYPE_TGID, ns); 1619 } 1620 task_tgid_vnr(struct task_struct * tsk)1621 static inline pid_t task_tgid_vnr(struct task_struct *tsk) 1622 { 1623 return __task_pid_nr_ns(tsk, PIDTYPE_TGID, NULL); 1624 } 1625 task_ppid_nr_ns(const struct task_struct * tsk,struct pid_namespace * ns)1626 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns) 1627 { 1628 pid_t pid = 0; 1629 1630 rcu_read_lock(); 1631 if (pid_alive(tsk)) 1632 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns); 1633 rcu_read_unlock(); 1634 1635 return pid; 1636 } 1637 task_ppid_nr(const struct task_struct * tsk)1638 static inline pid_t task_ppid_nr(const struct task_struct *tsk) 1639 { 1640 return task_ppid_nr_ns(tsk, &init_pid_ns); 1641 } 1642 1643 /* Obsolete, do not use: */ task_pgrp_nr(struct task_struct * tsk)1644 static inline pid_t task_pgrp_nr(struct task_struct *tsk) 1645 { 1646 return task_pgrp_nr_ns(tsk, &init_pid_ns); 1647 } 1648 1649 #define TASK_REPORT_IDLE (TASK_REPORT + 1) 1650 #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1) 1651 task_state_index(struct task_struct * tsk)1652 static inline unsigned int task_state_index(struct task_struct *tsk) 1653 { 1654 unsigned int tsk_state = READ_ONCE(tsk->__state); 1655 unsigned int state = (tsk_state | tsk->exit_state) & TASK_REPORT; 1656 1657 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX); 1658 1659 if (tsk_state == TASK_IDLE) 1660 state = TASK_REPORT_IDLE; 1661 1662 /* 1663 * We're lying here, but rather than expose a completely new task state 1664 * to userspace, we can make this appear as if the task has gone through 1665 * a regular rt_mutex_lock() call. 1666 */ 1667 if (tsk_state == TASK_RTLOCK_WAIT) 1668 state = TASK_UNINTERRUPTIBLE; 1669 1670 return fls(state); 1671 } 1672 task_index_to_char(unsigned int state)1673 static inline char task_index_to_char(unsigned int state) 1674 { 1675 static const char state_char[] = "RSDTtXZPI"; 1676 1677 BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1); 1678 1679 return state_char[state]; 1680 } 1681 task_state_to_char(struct task_struct * tsk)1682 static inline char task_state_to_char(struct task_struct *tsk) 1683 { 1684 return task_index_to_char(task_state_index(tsk)); 1685 } 1686 1687 /** 1688 * is_global_init - check if a task structure is init. Since init 1689 * is free to have sub-threads we need to check tgid. 1690 * @tsk: Task structure to be checked. 1691 * 1692 * Check if a task structure is the first user space task the kernel created. 1693 * 1694 * Return: 1 if the task structure is init. 0 otherwise. 1695 */ is_global_init(struct task_struct * tsk)1696 static inline int is_global_init(struct task_struct *tsk) 1697 { 1698 return task_tgid_nr(tsk) == 1; 1699 } 1700 1701 extern struct pid *cad_pid; 1702 1703 /* 1704 * Per process flags 1705 */ 1706 #define PF_VCPU 0x00000001 /* I'm a virtual CPU */ 1707 #define PF_IDLE 0x00000002 /* I am an IDLE thread */ 1708 #define PF_EXITING 0x00000004 /* Getting shut down */ 1709 #define PF_IO_WORKER 0x00000010 /* Task is an IO worker */ 1710 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 1711 #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */ 1712 #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */ 1713 #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */ 1714 #define PF_DUMPCORE 0x00000200 /* Dumped core */ 1715 #define PF_SIGNALED 0x00000400 /* Killed by a signal */ 1716 #define PF_MEMALLOC 0x00000800 /* Allocating memory */ 1717 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */ 1718 #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */ 1719 #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */ 1720 #define PF_FROZEN 0x00010000 /* Frozen for system suspend */ 1721 #define PF_KSWAPD 0x00020000 /* I am kswapd */ 1722 #define PF_MEMALLOC_NOFS 0x00040000 /* All allocation requests will inherit GFP_NOFS */ 1723 #define PF_MEMALLOC_NOIO 0x00080000 /* All allocation requests will inherit GFP_NOIO */ 1724 #define PF_LOCAL_THROTTLE 0x00100000 /* Throttle writes only against the bdi I write to, 1725 * I am cleaning dirty pages from some other bdi. */ 1726 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 1727 #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */ 1728 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 1729 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */ 1730 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 1731 #define PF_MEMALLOC_PIN 0x10000000 /* Allocation context constrained to zones which allow long term pinning. */ 1732 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ 1733 #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */ 1734 1735 /* 1736 * Only the _current_ task can read/write to tsk->flags, but other 1737 * tasks can access tsk->flags in readonly mode for example 1738 * with tsk_used_math (like during threaded core dumping). 1739 * There is however an exception to this rule during ptrace 1740 * or during fork: the ptracer task is allowed to write to the 1741 * child->flags of its traced child (same goes for fork, the parent 1742 * can write to the child->flags), because we're guaranteed the 1743 * child is not running and in turn not changing child->flags 1744 * at the same time the parent does it. 1745 */ 1746 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1747 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1748 #define clear_used_math() clear_stopped_child_used_math(current) 1749 #define set_used_math() set_stopped_child_used_math(current) 1750 1751 #define conditional_stopped_child_used_math(condition, child) \ 1752 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1753 1754 #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current) 1755 1756 #define copy_to_stopped_child_used_math(child) \ 1757 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1758 1759 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1760 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1761 #define used_math() tsk_used_math(current) 1762 is_percpu_thread(void)1763 static __always_inline bool is_percpu_thread(void) 1764 { 1765 #ifdef CONFIG_SMP 1766 return (current->flags & PF_NO_SETAFFINITY) && 1767 (current->nr_cpus_allowed == 1); 1768 #else 1769 return true; 1770 #endif 1771 } 1772 1773 /* Per-process atomic flags. */ 1774 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */ 1775 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */ 1776 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */ 1777 #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */ 1778 #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/ 1779 #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */ 1780 #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */ 1781 #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */ 1782 1783 #define TASK_PFA_TEST(name, func) \ 1784 static inline bool task_##func(struct task_struct *p) \ 1785 { return test_bit(PFA_##name, &p->atomic_flags); } 1786 1787 #define TASK_PFA_SET(name, func) \ 1788 static inline void task_set_##func(struct task_struct *p) \ 1789 { set_bit(PFA_##name, &p->atomic_flags); } 1790 1791 #define TASK_PFA_CLEAR(name, func) \ 1792 static inline void task_clear_##func(struct task_struct *p) \ 1793 { clear_bit(PFA_##name, &p->atomic_flags); } 1794 TASK_PFA_TEST(NO_NEW_PRIVS,no_new_privs)1795 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs) 1796 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs) 1797 1798 TASK_PFA_TEST(SPREAD_PAGE, spread_page) 1799 TASK_PFA_SET(SPREAD_PAGE, spread_page) 1800 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page) 1801 1802 TASK_PFA_TEST(SPREAD_SLAB, spread_slab) 1803 TASK_PFA_SET(SPREAD_SLAB, spread_slab) 1804 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab) 1805 1806 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable) 1807 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable) 1808 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable) 1809 1810 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1811 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1812 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1813 1814 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1815 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1816 1817 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable) 1818 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable) 1819 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable) 1820 1821 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1822 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1823 1824 static inline void 1825 current_restore_flags(unsigned long orig_flags, unsigned long flags) 1826 { 1827 current->flags &= ~flags; 1828 current->flags |= orig_flags & flags; 1829 } 1830 1831 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 1832 extern int task_can_attach(struct task_struct *p); 1833 extern int dl_bw_alloc(int cpu, u64 dl_bw); 1834 extern void dl_bw_free(int cpu, u64 dl_bw); 1835 1836 #ifdef CONFIG_RT_SOFTINT_OPTIMIZATION 1837 extern bool cpupri_check_rt(void); 1838 #else cpupri_check_rt(void)1839 static inline bool cpupri_check_rt(void) 1840 { 1841 return false; 1842 } 1843 #endif 1844 1845 #ifdef CONFIG_SMP 1846 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask); 1847 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask); 1848 extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node); 1849 extern void release_user_cpus_ptr(struct task_struct *p); 1850 extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask); 1851 extern void force_compatible_cpus_allowed_ptr(struct task_struct *p); 1852 extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p); 1853 #else do_set_cpus_allowed(struct task_struct * p,const struct cpumask * new_mask)1854 static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) 1855 { 1856 } set_cpus_allowed_ptr(struct task_struct * p,const struct cpumask * new_mask)1857 static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask) 1858 { 1859 if (!cpumask_test_cpu(0, new_mask)) 1860 return -EINVAL; 1861 return 0; 1862 } dup_user_cpus_ptr(struct task_struct * dst,struct task_struct * src,int node)1863 static inline int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node) 1864 { 1865 if (src->user_cpus_ptr) 1866 return -EINVAL; 1867 return 0; 1868 } release_user_cpus_ptr(struct task_struct * p)1869 static inline void release_user_cpus_ptr(struct task_struct *p) 1870 { 1871 WARN_ON(p->user_cpus_ptr); 1872 } 1873 dl_task_check_affinity(struct task_struct * p,const struct cpumask * mask)1874 static inline int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask) 1875 { 1876 return 0; 1877 } 1878 #endif 1879 1880 extern int yield_to(struct task_struct *p, bool preempt); 1881 extern void set_user_nice(struct task_struct *p, long nice); 1882 extern int task_prio(const struct task_struct *p); 1883 1884 /** 1885 * task_nice - return the nice value of a given task. 1886 * @p: the task in question. 1887 * 1888 * Return: The nice value [ -20 ... 0 ... 19 ]. 1889 */ task_nice(const struct task_struct * p)1890 static inline int task_nice(const struct task_struct *p) 1891 { 1892 return PRIO_TO_NICE((p)->static_prio); 1893 } 1894 1895 extern int can_nice(const struct task_struct *p, const int nice); 1896 extern int task_curr(const struct task_struct *p); 1897 extern int idle_cpu(int cpu); 1898 extern int available_idle_cpu(int cpu); 1899 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *); 1900 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *); 1901 extern void sched_set_fifo(struct task_struct *p); 1902 extern void sched_set_fifo_low(struct task_struct *p); 1903 extern void sched_set_normal(struct task_struct *p, int nice); 1904 extern int sched_setattr(struct task_struct *, const struct sched_attr *); 1905 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *); 1906 extern struct task_struct *idle_task(int cpu); 1907 1908 /** 1909 * is_idle_task - is the specified task an idle task? 1910 * @p: the task in question. 1911 * 1912 * Return: 1 if @p is an idle task. 0 otherwise. 1913 */ is_idle_task(const struct task_struct * p)1914 static __always_inline bool is_idle_task(const struct task_struct *p) 1915 { 1916 return !!(p->flags & PF_IDLE); 1917 } 1918 1919 extern struct task_struct *curr_task(int cpu); 1920 extern void ia64_set_curr_task(int cpu, struct task_struct *p); 1921 1922 void yield(void); 1923 1924 union thread_union { 1925 #ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK 1926 struct task_struct task; 1927 #endif 1928 #ifndef CONFIG_THREAD_INFO_IN_TASK 1929 struct thread_info thread_info; 1930 #endif 1931 unsigned long stack[THREAD_SIZE/sizeof(long)]; 1932 }; 1933 1934 #ifndef CONFIG_THREAD_INFO_IN_TASK 1935 extern struct thread_info init_thread_info; 1936 #endif 1937 1938 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)]; 1939 1940 #ifdef CONFIG_THREAD_INFO_IN_TASK task_thread_info(struct task_struct * task)1941 static inline struct thread_info *task_thread_info(struct task_struct *task) 1942 { 1943 return &task->thread_info; 1944 } 1945 #elif !defined(__HAVE_THREAD_FUNCTIONS) 1946 # define task_thread_info(task) ((struct thread_info *)(task)->stack) 1947 #endif 1948 1949 /* 1950 * find a task by one of its numerical ids 1951 * 1952 * find_task_by_pid_ns(): 1953 * finds a task by its pid in the specified namespace 1954 * find_task_by_vpid(): 1955 * finds a task by its virtual pid 1956 * 1957 * see also find_vpid() etc in include/linux/pid.h 1958 */ 1959 1960 extern struct task_struct *find_task_by_vpid(pid_t nr); 1961 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns); 1962 1963 /* 1964 * find a task by its virtual pid and get the task struct 1965 */ 1966 extern struct task_struct *find_get_task_by_vpid(pid_t nr); 1967 1968 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 1969 extern int wake_up_process(struct task_struct *tsk); 1970 extern void wake_up_new_task(struct task_struct *tsk); 1971 1972 #ifdef CONFIG_SMP 1973 extern void kick_process(struct task_struct *tsk); 1974 #else kick_process(struct task_struct * tsk)1975 static inline void kick_process(struct task_struct *tsk) { } 1976 #endif 1977 1978 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); 1979 set_task_comm(struct task_struct * tsk,const char * from)1980 static inline void set_task_comm(struct task_struct *tsk, const char *from) 1981 { 1982 __set_task_comm(tsk, from, false); 1983 } 1984 1985 extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk); 1986 #define get_task_comm(buf, tsk) ({ \ 1987 BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN); \ 1988 __get_task_comm(buf, sizeof(buf), tsk); \ 1989 }) 1990 1991 #ifdef CONFIG_SMP scheduler_ipi(void)1992 static __always_inline void scheduler_ipi(void) 1993 { 1994 /* 1995 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting 1996 * TIF_NEED_RESCHED remotely (for the first time) will also send 1997 * this IPI. 1998 */ 1999 preempt_fold_need_resched(); 2000 } 2001 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state); 2002 #else scheduler_ipi(void)2003 static inline void scheduler_ipi(void) { } wait_task_inactive(struct task_struct * p,unsigned int match_state)2004 static inline unsigned long wait_task_inactive(struct task_struct *p, unsigned int match_state) 2005 { 2006 return 1; 2007 } 2008 #endif 2009 2010 /* 2011 * Set thread flags in other task's structures. 2012 * See asm/thread_info.h for TIF_xxxx flags available: 2013 */ set_tsk_thread_flag(struct task_struct * tsk,int flag)2014 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 2015 { 2016 set_ti_thread_flag(task_thread_info(tsk), flag); 2017 } 2018 clear_tsk_thread_flag(struct task_struct * tsk,int flag)2019 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2020 { 2021 clear_ti_thread_flag(task_thread_info(tsk), flag); 2022 } 2023 update_tsk_thread_flag(struct task_struct * tsk,int flag,bool value)2024 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag, 2025 bool value) 2026 { 2027 update_ti_thread_flag(task_thread_info(tsk), flag, value); 2028 } 2029 test_and_set_tsk_thread_flag(struct task_struct * tsk,int flag)2030 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 2031 { 2032 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 2033 } 2034 test_and_clear_tsk_thread_flag(struct task_struct * tsk,int flag)2035 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2036 { 2037 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 2038 } 2039 test_tsk_thread_flag(struct task_struct * tsk,int flag)2040 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 2041 { 2042 return test_ti_thread_flag(task_thread_info(tsk), flag); 2043 } 2044 set_tsk_need_resched(struct task_struct * tsk)2045 static inline void set_tsk_need_resched(struct task_struct *tsk) 2046 { 2047 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2048 } 2049 clear_tsk_need_resched(struct task_struct * tsk)2050 static inline void clear_tsk_need_resched(struct task_struct *tsk) 2051 { 2052 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2053 } 2054 test_tsk_need_resched(struct task_struct * tsk)2055 static inline int test_tsk_need_resched(struct task_struct *tsk) 2056 { 2057 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 2058 } 2059 2060 /* 2061 * cond_resched() and cond_resched_lock(): latency reduction via 2062 * explicit rescheduling in places that are safe. The return 2063 * value indicates whether a reschedule was done in fact. 2064 * cond_resched_lock() will drop the spinlock before scheduling, 2065 */ 2066 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) 2067 extern int __cond_resched(void); 2068 2069 #ifdef CONFIG_PREEMPT_DYNAMIC 2070 2071 DECLARE_STATIC_CALL(cond_resched, __cond_resched); 2072 _cond_resched(void)2073 static __always_inline int _cond_resched(void) 2074 { 2075 return static_call_mod(cond_resched)(); 2076 } 2077 2078 #else 2079 _cond_resched(void)2080 static inline int _cond_resched(void) 2081 { 2082 return __cond_resched(); 2083 } 2084 2085 #endif /* CONFIG_PREEMPT_DYNAMIC */ 2086 2087 #else 2088 _cond_resched(void)2089 static inline int _cond_resched(void) { return 0; } 2090 2091 #endif /* !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) */ 2092 2093 #define cond_resched() ({ \ 2094 ___might_sleep(__FILE__, __LINE__, 0); \ 2095 _cond_resched(); \ 2096 }) 2097 2098 extern int __cond_resched_lock(spinlock_t *lock); 2099 extern int __cond_resched_rwlock_read(rwlock_t *lock); 2100 extern int __cond_resched_rwlock_write(rwlock_t *lock); 2101 2102 #define cond_resched_lock(lock) ({ \ 2103 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\ 2104 __cond_resched_lock(lock); \ 2105 }) 2106 2107 #define cond_resched_rwlock_read(lock) ({ \ 2108 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \ 2109 __cond_resched_rwlock_read(lock); \ 2110 }) 2111 2112 #define cond_resched_rwlock_write(lock) ({ \ 2113 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \ 2114 __cond_resched_rwlock_write(lock); \ 2115 }) 2116 cond_resched_rcu(void)2117 static inline void cond_resched_rcu(void) 2118 { 2119 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) 2120 rcu_read_unlock(); 2121 cond_resched(); 2122 rcu_read_lock(); 2123 #endif 2124 } 2125 2126 /* 2127 * Does a critical section need to be broken due to another 2128 * task waiting?: (technically does not depend on CONFIG_PREEMPTION, 2129 * but a general need for low latency) 2130 */ spin_needbreak(spinlock_t * lock)2131 static inline int spin_needbreak(spinlock_t *lock) 2132 { 2133 #ifdef CONFIG_PREEMPTION 2134 return spin_is_contended(lock); 2135 #else 2136 return 0; 2137 #endif 2138 } 2139 2140 /* 2141 * Check if a rwlock is contended. 2142 * Returns non-zero if there is another task waiting on the rwlock. 2143 * Returns zero if the lock is not contended or the system / underlying 2144 * rwlock implementation does not support contention detection. 2145 * Technically does not depend on CONFIG_PREEMPTION, but a general need 2146 * for low latency. 2147 */ rwlock_needbreak(rwlock_t * lock)2148 static inline int rwlock_needbreak(rwlock_t *lock) 2149 { 2150 #ifdef CONFIG_PREEMPTION 2151 return rwlock_is_contended(lock); 2152 #else 2153 return 0; 2154 #endif 2155 } 2156 need_resched(void)2157 static __always_inline bool need_resched(void) 2158 { 2159 return unlikely(tif_need_resched()); 2160 } 2161 2162 /* 2163 * Wrappers for p->thread_info->cpu access. No-op on UP. 2164 */ 2165 #ifdef CONFIG_SMP 2166 task_cpu(const struct task_struct * p)2167 static inline unsigned int task_cpu(const struct task_struct *p) 2168 { 2169 #ifdef CONFIG_THREAD_INFO_IN_TASK 2170 return READ_ONCE(p->cpu); 2171 #else 2172 return READ_ONCE(task_thread_info(p)->cpu); 2173 #endif 2174 } 2175 2176 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 2177 2178 #else 2179 task_cpu(const struct task_struct * p)2180 static inline unsigned int task_cpu(const struct task_struct *p) 2181 { 2182 return 0; 2183 } 2184 set_task_cpu(struct task_struct * p,unsigned int cpu)2185 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 2186 { 2187 } 2188 2189 #endif /* CONFIG_SMP */ 2190 2191 extern bool sched_task_on_rq(struct task_struct *p); 2192 2193 /* 2194 * In order to reduce various lock holder preemption latencies provide an 2195 * interface to see if a vCPU is currently running or not. 2196 * 2197 * This allows us to terminate optimistic spin loops and block, analogous to 2198 * the native optimistic spin heuristic of testing if the lock owner task is 2199 * running or not. 2200 */ 2201 #ifndef vcpu_is_preempted vcpu_is_preempted(int cpu)2202 static inline bool vcpu_is_preempted(int cpu) 2203 { 2204 return false; 2205 } 2206 #endif 2207 2208 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 2209 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 2210 2211 #ifndef TASK_SIZE_OF 2212 #define TASK_SIZE_OF(tsk) TASK_SIZE 2213 #endif 2214 2215 #ifdef CONFIG_SMP 2216 /* Returns effective CPU energy utilization, as seen by the scheduler */ 2217 unsigned long sched_cpu_util(int cpu, unsigned long max); 2218 #endif /* CONFIG_SMP */ 2219 2220 #ifdef CONFIG_RSEQ 2221 2222 /* 2223 * Map the event mask on the user-space ABI enum rseq_cs_flags 2224 * for direct mask checks. 2225 */ 2226 enum rseq_event_mask_bits { 2227 RSEQ_EVENT_PREEMPT_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT, 2228 RSEQ_EVENT_SIGNAL_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT, 2229 RSEQ_EVENT_MIGRATE_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT, 2230 }; 2231 2232 enum rseq_event_mask { 2233 RSEQ_EVENT_PREEMPT = (1U << RSEQ_EVENT_PREEMPT_BIT), 2234 RSEQ_EVENT_SIGNAL = (1U << RSEQ_EVENT_SIGNAL_BIT), 2235 RSEQ_EVENT_MIGRATE = (1U << RSEQ_EVENT_MIGRATE_BIT), 2236 }; 2237 rseq_set_notify_resume(struct task_struct * t)2238 static inline void rseq_set_notify_resume(struct task_struct *t) 2239 { 2240 if (t->rseq) 2241 set_tsk_thread_flag(t, TIF_NOTIFY_RESUME); 2242 } 2243 2244 void __rseq_handle_notify_resume(struct ksignal *sig, struct pt_regs *regs); 2245 rseq_handle_notify_resume(struct ksignal * ksig,struct pt_regs * regs)2246 static inline void rseq_handle_notify_resume(struct ksignal *ksig, 2247 struct pt_regs *regs) 2248 { 2249 if (current->rseq) 2250 __rseq_handle_notify_resume(ksig, regs); 2251 } 2252 rseq_signal_deliver(struct ksignal * ksig,struct pt_regs * regs)2253 static inline void rseq_signal_deliver(struct ksignal *ksig, 2254 struct pt_regs *regs) 2255 { 2256 preempt_disable(); 2257 __set_bit(RSEQ_EVENT_SIGNAL_BIT, ¤t->rseq_event_mask); 2258 preempt_enable(); 2259 rseq_handle_notify_resume(ksig, regs); 2260 } 2261 2262 /* rseq_preempt() requires preemption to be disabled. */ rseq_preempt(struct task_struct * t)2263 static inline void rseq_preempt(struct task_struct *t) 2264 { 2265 __set_bit(RSEQ_EVENT_PREEMPT_BIT, &t->rseq_event_mask); 2266 rseq_set_notify_resume(t); 2267 } 2268 2269 /* rseq_migrate() requires preemption to be disabled. */ rseq_migrate(struct task_struct * t)2270 static inline void rseq_migrate(struct task_struct *t) 2271 { 2272 __set_bit(RSEQ_EVENT_MIGRATE_BIT, &t->rseq_event_mask); 2273 rseq_set_notify_resume(t); 2274 } 2275 2276 /* 2277 * If parent process has a registered restartable sequences area, the 2278 * child inherits. Unregister rseq for a clone with CLONE_VM set. 2279 */ rseq_fork(struct task_struct * t,unsigned long clone_flags)2280 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags) 2281 { 2282 if (clone_flags & CLONE_VM) { 2283 t->rseq = NULL; 2284 t->rseq_sig = 0; 2285 t->rseq_event_mask = 0; 2286 } else { 2287 t->rseq = current->rseq; 2288 t->rseq_sig = current->rseq_sig; 2289 t->rseq_event_mask = current->rseq_event_mask; 2290 } 2291 } 2292 rseq_execve(struct task_struct * t)2293 static inline void rseq_execve(struct task_struct *t) 2294 { 2295 t->rseq = NULL; 2296 t->rseq_sig = 0; 2297 t->rseq_event_mask = 0; 2298 } 2299 2300 #else 2301 rseq_set_notify_resume(struct task_struct * t)2302 static inline void rseq_set_notify_resume(struct task_struct *t) 2303 { 2304 } rseq_handle_notify_resume(struct ksignal * ksig,struct pt_regs * regs)2305 static inline void rseq_handle_notify_resume(struct ksignal *ksig, 2306 struct pt_regs *regs) 2307 { 2308 } rseq_signal_deliver(struct ksignal * ksig,struct pt_regs * regs)2309 static inline void rseq_signal_deliver(struct ksignal *ksig, 2310 struct pt_regs *regs) 2311 { 2312 } rseq_preempt(struct task_struct * t)2313 static inline void rseq_preempt(struct task_struct *t) 2314 { 2315 } rseq_migrate(struct task_struct * t)2316 static inline void rseq_migrate(struct task_struct *t) 2317 { 2318 } rseq_fork(struct task_struct * t,unsigned long clone_flags)2319 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags) 2320 { 2321 } rseq_execve(struct task_struct * t)2322 static inline void rseq_execve(struct task_struct *t) 2323 { 2324 } 2325 2326 #endif 2327 2328 #ifdef CONFIG_DEBUG_RSEQ 2329 2330 void rseq_syscall(struct pt_regs *regs); 2331 2332 #else 2333 rseq_syscall(struct pt_regs * regs)2334 static inline void rseq_syscall(struct pt_regs *regs) 2335 { 2336 } 2337 2338 #endif 2339 2340 const struct sched_avg *sched_trace_cfs_rq_avg(struct cfs_rq *cfs_rq); 2341 char *sched_trace_cfs_rq_path(struct cfs_rq *cfs_rq, char *str, int len); 2342 int sched_trace_cfs_rq_cpu(struct cfs_rq *cfs_rq); 2343 2344 const struct sched_avg *sched_trace_rq_avg_rt(struct rq *rq); 2345 const struct sched_avg *sched_trace_rq_avg_dl(struct rq *rq); 2346 const struct sched_avg *sched_trace_rq_avg_irq(struct rq *rq); 2347 2348 int sched_trace_rq_cpu(struct rq *rq); 2349 int sched_trace_rq_cpu_capacity(struct rq *rq); 2350 int sched_trace_rq_nr_running(struct rq *rq); 2351 2352 const struct cpumask *sched_trace_rd_span(struct root_domain *rd); 2353 2354 #ifdef CONFIG_SCHED_CORE 2355 extern void sched_core_free(struct task_struct *tsk); 2356 extern void sched_core_fork(struct task_struct *p); 2357 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type, 2358 unsigned long uaddr); 2359 #else sched_core_free(struct task_struct * tsk)2360 static inline void sched_core_free(struct task_struct *tsk) { } sched_core_fork(struct task_struct * p)2361 static inline void sched_core_fork(struct task_struct *p) { } 2362 #endif 2363 2364 #endif 2365