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 <asm/kmap_size.h> 38 39 /* task_struct member predeclarations (sorted alphabetically): */ 40 struct audit_context; 41 struct backing_dev_info; 42 struct bio_list; 43 struct blk_plug; 44 struct bpf_local_storage; 45 struct capture_control; 46 struct cfs_rq; 47 struct fs_struct; 48 struct futex_pi_state; 49 struct io_context; 50 struct io_uring_task; 51 struct mempolicy; 52 struct nameidata; 53 struct nsproxy; 54 struct perf_event_context; 55 struct pid_namespace; 56 struct pipe_inode_info; 57 struct rcu_node; 58 struct reclaim_state; 59 struct robust_list_head; 60 struct root_domain; 61 struct rq; 62 struct sched_attr; 63 struct sched_param; 64 struct seq_file; 65 struct sighand_struct; 66 struct signal_struct; 67 struct task_delay_info; 68 struct task_group; 69 70 /* 71 * Task state bitmask. NOTE! These bits are also 72 * encoded in fs/proc/array.c: get_task_state(). 73 * 74 * We have two separate sets of flags: task->state 75 * is about runnability, while task->exit_state are 76 * about the task exiting. Confusing, but this way 77 * modifying one set can't modify the other one by 78 * mistake. 79 */ 80 81 /* Used in tsk->state: */ 82 #define TASK_RUNNING 0x0000 83 #define TASK_INTERRUPTIBLE 0x0001 84 #define TASK_UNINTERRUPTIBLE 0x0002 85 #define __TASK_STOPPED 0x0004 86 #define __TASK_TRACED 0x0008 87 /* Used in tsk->exit_state: */ 88 #define EXIT_DEAD 0x0010 89 #define EXIT_ZOMBIE 0x0020 90 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD) 91 /* Used in tsk->state again: */ 92 #define TASK_PARKED 0x0040 93 #define TASK_DEAD 0x0080 94 #define TASK_WAKEKILL 0x0100 95 #define TASK_WAKING 0x0200 96 #define TASK_NOLOAD 0x0400 97 #define TASK_NEW 0x0800 98 #define TASK_STATE_MAX 0x1000 99 100 /* Convenience macros for the sake of set_current_state: */ 101 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 102 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 103 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED) 104 105 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD) 106 107 /* Convenience macros for the sake of wake_up(): */ 108 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 109 110 /* get_task_state(): */ 111 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 112 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 113 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \ 114 TASK_PARKED) 115 116 #define task_is_running(task) (READ_ONCE((task)->__state) == TASK_RUNNING) 117 118 #define task_is_traced(task) ((READ_ONCE(task->__state) & __TASK_TRACED) != 0) 119 120 #define task_is_stopped(task) ((READ_ONCE(task->__state) & __TASK_STOPPED) != 0) 121 122 #define task_is_stopped_or_traced(task) ((READ_ONCE(task->__state) & (__TASK_STOPPED | __TASK_TRACED)) != 0) 123 124 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 125 126 /* 127 * Special states are those that do not use the normal wait-loop pattern. See 128 * the comment with set_special_state(). 129 */ 130 #define is_special_task_state(state) \ 131 ((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD)) 132 133 #define __set_current_state(state_value) \ 134 do { \ 135 WARN_ON_ONCE(is_special_task_state(state_value));\ 136 current->task_state_change = _THIS_IP_; \ 137 WRITE_ONCE(current->__state, (state_value)); \ 138 } while (0) 139 140 #define set_current_state(state_value) \ 141 do { \ 142 WARN_ON_ONCE(is_special_task_state(state_value));\ 143 current->task_state_change = _THIS_IP_; \ 144 smp_store_mb(current->__state, (state_value)); \ 145 } while (0) 146 147 #define set_special_state(state_value) \ 148 do { \ 149 unsigned long flags; /* may shadow */ \ 150 WARN_ON_ONCE(!is_special_task_state(state_value)); \ 151 raw_spin_lock_irqsave(¤t->pi_lock, flags); \ 152 current->task_state_change = _THIS_IP_; \ 153 WRITE_ONCE(current->__state, (state_value)); \ 154 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \ 155 } while (0) 156 #else 157 /* 158 * set_current_state() includes a barrier so that the write of current->state 159 * is correctly serialised wrt the caller's subsequent test of whether to 160 * actually sleep: 161 * 162 * for (;;) { 163 * set_current_state(TASK_UNINTERRUPTIBLE); 164 * if (CONDITION) 165 * break; 166 * 167 * schedule(); 168 * } 169 * __set_current_state(TASK_RUNNING); 170 * 171 * If the caller does not need such serialisation (because, for instance, the 172 * CONDITION test and condition change and wakeup are under the same lock) then 173 * use __set_current_state(). 174 * 175 * The above is typically ordered against the wakeup, which does: 176 * 177 * CONDITION = 1; 178 * wake_up_state(p, TASK_UNINTERRUPTIBLE); 179 * 180 * where wake_up_state()/try_to_wake_up() executes a full memory barrier before 181 * accessing p->state. 182 * 183 * Wakeup will do: if (@state & p->state) p->state = TASK_RUNNING, that is, 184 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a 185 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING). 186 * 187 * However, with slightly different timing the wakeup TASK_RUNNING store can 188 * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not 189 * a problem either because that will result in one extra go around the loop 190 * and our @cond test will save the day. 191 * 192 * Also see the comments of try_to_wake_up(). 193 */ 194 #define __set_current_state(state_value) \ 195 WRITE_ONCE(current->__state, (state_value)) 196 197 #define set_current_state(state_value) \ 198 smp_store_mb(current->__state, (state_value)) 199 200 /* 201 * set_special_state() should be used for those states when the blocking task 202 * can not use the regular condition based wait-loop. In that case we must 203 * serialize against wakeups such that any possible in-flight TASK_RUNNING stores 204 * will not collide with our state change. 205 */ 206 #define set_special_state(state_value) \ 207 do { \ 208 unsigned long flags; /* may shadow */ \ 209 raw_spin_lock_irqsave(¤t->pi_lock, flags); \ 210 WRITE_ONCE(current->__state, (state_value)); \ 211 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \ 212 } while (0) 213 214 #endif 215 216 #define get_current_state() READ_ONCE(current->__state) 217 218 /* Task command name length: */ 219 #define TASK_COMM_LEN 16 220 221 extern void scheduler_tick(void); 222 223 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 224 225 extern long schedule_timeout(long timeout); 226 extern long schedule_timeout_interruptible(long timeout); 227 extern long schedule_timeout_killable(long timeout); 228 extern long schedule_timeout_uninterruptible(long timeout); 229 extern long schedule_timeout_idle(long timeout); 230 asmlinkage void schedule(void); 231 extern void schedule_preempt_disabled(void); 232 asmlinkage void preempt_schedule_irq(void); 233 234 extern int __must_check io_schedule_prepare(void); 235 extern void io_schedule_finish(int token); 236 extern long io_schedule_timeout(long timeout); 237 extern void io_schedule(void); 238 239 /** 240 * struct prev_cputime - snapshot of system and user cputime 241 * @utime: time spent in user mode 242 * @stime: time spent in system mode 243 * @lock: protects the above two fields 244 * 245 * Stores previous user/system time values such that we can guarantee 246 * monotonicity. 247 */ 248 struct prev_cputime { 249 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 250 u64 utime; 251 u64 stime; 252 raw_spinlock_t lock; 253 #endif 254 }; 255 256 enum vtime_state { 257 /* Task is sleeping or running in a CPU with VTIME inactive: */ 258 VTIME_INACTIVE = 0, 259 /* Task is idle */ 260 VTIME_IDLE, 261 /* Task runs in kernelspace in a CPU with VTIME active: */ 262 VTIME_SYS, 263 /* Task runs in userspace in a CPU with VTIME active: */ 264 VTIME_USER, 265 /* Task runs as guests in a CPU with VTIME active: */ 266 VTIME_GUEST, 267 }; 268 269 struct vtime { 270 seqcount_t seqcount; 271 unsigned long long starttime; 272 enum vtime_state state; 273 unsigned int cpu; 274 u64 utime; 275 u64 stime; 276 u64 gtime; 277 }; 278 279 /* 280 * Utilization clamp constraints. 281 * @UCLAMP_MIN: Minimum utilization 282 * @UCLAMP_MAX: Maximum utilization 283 * @UCLAMP_CNT: Utilization clamp constraints count 284 */ 285 enum uclamp_id { 286 UCLAMP_MIN = 0, 287 UCLAMP_MAX, 288 UCLAMP_CNT 289 }; 290 291 #ifdef CONFIG_SMP 292 extern struct root_domain def_root_domain; 293 extern struct mutex sched_domains_mutex; 294 #endif 295 296 struct sched_info { 297 #ifdef CONFIG_SCHED_INFO 298 /* Cumulative counters: */ 299 300 /* # of times we have run on this CPU: */ 301 unsigned long pcount; 302 303 /* Time spent waiting on a runqueue: */ 304 unsigned long long run_delay; 305 306 /* Timestamps: */ 307 308 /* When did we last run on a CPU? */ 309 unsigned long long last_arrival; 310 311 /* When were we last queued to run? */ 312 unsigned long long last_queued; 313 314 #endif /* CONFIG_SCHED_INFO */ 315 }; 316 317 /* 318 * Integer metrics need fixed point arithmetic, e.g., sched/fair 319 * has a few: load, load_avg, util_avg, freq, and capacity. 320 * 321 * We define a basic fixed point arithmetic range, and then formalize 322 * all these metrics based on that basic range. 323 */ 324 # define SCHED_FIXEDPOINT_SHIFT 10 325 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT) 326 327 /* Increase resolution of cpu_capacity calculations */ 328 # define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT 329 # define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) 330 331 struct load_weight { 332 unsigned long weight; 333 u32 inv_weight; 334 }; 335 336 /** 337 * struct util_est - Estimation utilization of FAIR tasks 338 * @enqueued: instantaneous estimated utilization of a task/cpu 339 * @ewma: the Exponential Weighted Moving Average (EWMA) 340 * utilization of a task 341 * 342 * Support data structure to track an Exponential Weighted Moving Average 343 * (EWMA) of a FAIR task's utilization. New samples are added to the moving 344 * average each time a task completes an activation. Sample's weight is chosen 345 * so that the EWMA will be relatively insensitive to transient changes to the 346 * task's workload. 347 * 348 * The enqueued attribute has a slightly different meaning for tasks and cpus: 349 * - task: the task's util_avg at last task dequeue time 350 * - cfs_rq: the sum of util_est.enqueued for each RUNNABLE task on that CPU 351 * Thus, the util_est.enqueued of a task represents the contribution on the 352 * estimated utilization of the CPU where that task is currently enqueued. 353 * 354 * Only for tasks we track a moving average of the past instantaneous 355 * estimated utilization. This allows to absorb sporadic drops in utilization 356 * of an otherwise almost periodic task. 357 * 358 * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg 359 * updates. When a task is dequeued, its util_est should not be updated if its 360 * util_avg has not been updated in the meantime. 361 * This information is mapped into the MSB bit of util_est.enqueued at dequeue 362 * time. Since max value of util_est.enqueued for a task is 1024 (PELT util_avg 363 * for a task) it is safe to use MSB. 364 */ 365 struct util_est { 366 unsigned int enqueued; 367 unsigned int ewma; 368 #define UTIL_EST_WEIGHT_SHIFT 2 369 #define UTIL_AVG_UNCHANGED 0x80000000 370 } __attribute__((__aligned__(sizeof(u64)))); 371 372 /* 373 * The load/runnable/util_avg accumulates an infinite geometric series 374 * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c). 375 * 376 * [load_avg definition] 377 * 378 * load_avg = runnable% * scale_load_down(load) 379 * 380 * [runnable_avg definition] 381 * 382 * runnable_avg = runnable% * SCHED_CAPACITY_SCALE 383 * 384 * [util_avg definition] 385 * 386 * util_avg = running% * SCHED_CAPACITY_SCALE 387 * 388 * where runnable% is the time ratio that a sched_entity is runnable and 389 * running% the time ratio that a sched_entity is running. 390 * 391 * For cfs_rq, they are the aggregated values of all runnable and blocked 392 * sched_entities. 393 * 394 * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU 395 * capacity scaling. The scaling is done through the rq_clock_pelt that is used 396 * for computing those signals (see update_rq_clock_pelt()) 397 * 398 * N.B., the above ratios (runnable% and running%) themselves are in the 399 * range of [0, 1]. To do fixed point arithmetics, we therefore scale them 400 * to as large a range as necessary. This is for example reflected by 401 * util_avg's SCHED_CAPACITY_SCALE. 402 * 403 * [Overflow issue] 404 * 405 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities 406 * with the highest load (=88761), always runnable on a single cfs_rq, 407 * and should not overflow as the number already hits PID_MAX_LIMIT. 408 * 409 * For all other cases (including 32-bit kernels), struct load_weight's 410 * weight will overflow first before we do, because: 411 * 412 * Max(load_avg) <= Max(load.weight) 413 * 414 * Then it is the load_weight's responsibility to consider overflow 415 * issues. 416 */ 417 struct sched_avg { 418 u64 last_update_time; 419 u64 load_sum; 420 u64 runnable_sum; 421 u32 util_sum; 422 u32 period_contrib; 423 unsigned long load_avg; 424 unsigned long runnable_avg; 425 unsigned long util_avg; 426 struct util_est util_est; 427 } ____cacheline_aligned; 428 429 struct sched_statistics { 430 #ifdef CONFIG_SCHEDSTATS 431 u64 wait_start; 432 u64 wait_max; 433 u64 wait_count; 434 u64 wait_sum; 435 u64 iowait_count; 436 u64 iowait_sum; 437 438 u64 sleep_start; 439 u64 sleep_max; 440 s64 sum_sleep_runtime; 441 442 u64 block_start; 443 u64 block_max; 444 u64 exec_max; 445 u64 slice_max; 446 447 u64 nr_migrations_cold; 448 u64 nr_failed_migrations_affine; 449 u64 nr_failed_migrations_running; 450 u64 nr_failed_migrations_hot; 451 u64 nr_forced_migrations; 452 453 u64 nr_wakeups; 454 u64 nr_wakeups_sync; 455 u64 nr_wakeups_migrate; 456 u64 nr_wakeups_local; 457 u64 nr_wakeups_remote; 458 u64 nr_wakeups_affine; 459 u64 nr_wakeups_affine_attempts; 460 u64 nr_wakeups_passive; 461 u64 nr_wakeups_idle; 462 #endif 463 }; 464 465 struct sched_entity { 466 /* For load-balancing: */ 467 struct load_weight load; 468 struct rb_node run_node; 469 struct list_head group_node; 470 unsigned int on_rq; 471 472 u64 exec_start; 473 u64 sum_exec_runtime; 474 u64 vruntime; 475 u64 prev_sum_exec_runtime; 476 477 u64 nr_migrations; 478 479 struct sched_statistics statistics; 480 481 #ifdef CONFIG_FAIR_GROUP_SCHED 482 int depth; 483 struct sched_entity *parent; 484 /* rq on which this entity is (to be) queued: */ 485 struct cfs_rq *cfs_rq; 486 /* rq "owned" by this entity/group: */ 487 struct cfs_rq *my_q; 488 /* cached value of my_q->h_nr_running */ 489 unsigned long runnable_weight; 490 #endif 491 492 #ifdef CONFIG_SMP 493 /* 494 * Per entity load average tracking. 495 * 496 * Put into separate cache line so it does not 497 * collide with read-mostly values above. 498 */ 499 struct sched_avg avg; 500 #endif 501 }; 502 503 struct sched_rt_entity { 504 struct list_head run_list; 505 unsigned long timeout; 506 unsigned long watchdog_stamp; 507 unsigned int time_slice; 508 unsigned short on_rq; 509 unsigned short on_list; 510 511 struct sched_rt_entity *back; 512 #ifdef CONFIG_RT_GROUP_SCHED 513 struct sched_rt_entity *parent; 514 /* rq on which this entity is (to be) queued: */ 515 struct rt_rq *rt_rq; 516 /* rq "owned" by this entity/group: */ 517 struct rt_rq *my_q; 518 #endif 519 } __randomize_layout; 520 521 struct sched_dl_entity { 522 struct rb_node rb_node; 523 524 /* 525 * Original scheduling parameters. Copied here from sched_attr 526 * during sched_setattr(), they will remain the same until 527 * the next sched_setattr(). 528 */ 529 u64 dl_runtime; /* Maximum runtime for each instance */ 530 u64 dl_deadline; /* Relative deadline of each instance */ 531 u64 dl_period; /* Separation of two instances (period) */ 532 u64 dl_bw; /* dl_runtime / dl_period */ 533 u64 dl_density; /* dl_runtime / dl_deadline */ 534 535 /* 536 * Actual scheduling parameters. Initialized with the values above, 537 * they are continuously updated during task execution. Note that 538 * the remaining runtime could be < 0 in case we are in overrun. 539 */ 540 s64 runtime; /* Remaining runtime for this instance */ 541 u64 deadline; /* Absolute deadline for this instance */ 542 unsigned int flags; /* Specifying the scheduler behaviour */ 543 544 /* 545 * Some bool flags: 546 * 547 * @dl_throttled tells if we exhausted the runtime. If so, the 548 * task has to wait for a replenishment to be performed at the 549 * next firing of dl_timer. 550 * 551 * @dl_boosted tells if we are boosted due to DI. If so we are 552 * outside bandwidth enforcement mechanism (but only until we 553 * exit the critical section); 554 * 555 * @dl_yielded tells if task gave up the CPU before consuming 556 * all its available runtime during the last job. 557 * 558 * @dl_non_contending tells if the task is inactive while still 559 * contributing to the active utilization. In other words, it 560 * indicates if the inactive timer has been armed and its handler 561 * has not been executed yet. This flag is useful to avoid race 562 * conditions between the inactive timer handler and the wakeup 563 * code. 564 * 565 * @dl_overrun tells if the task asked to be informed about runtime 566 * overruns. 567 */ 568 unsigned int dl_throttled : 1; 569 unsigned int dl_yielded : 1; 570 unsigned int dl_non_contending : 1; 571 unsigned int dl_overrun : 1; 572 573 /* 574 * Bandwidth enforcement timer. Each -deadline task has its 575 * own bandwidth to be enforced, thus we need one timer per task. 576 */ 577 struct hrtimer dl_timer; 578 579 /* 580 * Inactive timer, responsible for decreasing the active utilization 581 * at the "0-lag time". When a -deadline task blocks, it contributes 582 * to GRUB's active utilization until the "0-lag time", hence a 583 * timer is needed to decrease the active utilization at the correct 584 * time. 585 */ 586 struct hrtimer inactive_timer; 587 588 #ifdef CONFIG_RT_MUTEXES 589 /* 590 * Priority Inheritance. When a DEADLINE scheduling entity is boosted 591 * pi_se points to the donor, otherwise points to the dl_se it belongs 592 * to (the original one/itself). 593 */ 594 struct sched_dl_entity *pi_se; 595 #endif 596 }; 597 598 #ifdef CONFIG_UCLAMP_TASK 599 /* Number of utilization clamp buckets (shorter alias) */ 600 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT 601 602 /* 603 * Utilization clamp for a scheduling entity 604 * @value: clamp value "assigned" to a se 605 * @bucket_id: bucket index corresponding to the "assigned" value 606 * @active: the se is currently refcounted in a rq's bucket 607 * @user_defined: the requested clamp value comes from user-space 608 * 609 * The bucket_id is the index of the clamp bucket matching the clamp value 610 * which is pre-computed and stored to avoid expensive integer divisions from 611 * the fast path. 612 * 613 * The active bit is set whenever a task has got an "effective" value assigned, 614 * which can be different from the clamp value "requested" from user-space. 615 * This allows to know a task is refcounted in the rq's bucket corresponding 616 * to the "effective" bucket_id. 617 * 618 * The user_defined bit is set whenever a task has got a task-specific clamp 619 * value requested from userspace, i.e. the system defaults apply to this task 620 * just as a restriction. This allows to relax default clamps when a less 621 * restrictive task-specific value has been requested, thus allowing to 622 * implement a "nice" semantic. For example, a task running with a 20% 623 * default boost can still drop its own boosting to 0%. 624 */ 625 struct uclamp_se { 626 unsigned int value : bits_per(SCHED_CAPACITY_SCALE); 627 unsigned int bucket_id : bits_per(UCLAMP_BUCKETS); 628 unsigned int active : 1; 629 unsigned int user_defined : 1; 630 }; 631 #endif /* CONFIG_UCLAMP_TASK */ 632 633 union rcu_special { 634 struct { 635 u8 blocked; 636 u8 need_qs; 637 u8 exp_hint; /* Hint for performance. */ 638 u8 need_mb; /* Readers need smp_mb(). */ 639 } b; /* Bits. */ 640 u32 s; /* Set of bits. */ 641 }; 642 643 enum perf_event_task_context { 644 perf_invalid_context = -1, 645 perf_hw_context = 0, 646 perf_sw_context, 647 perf_nr_task_contexts, 648 }; 649 650 struct wake_q_node { 651 struct wake_q_node *next; 652 }; 653 654 struct kmap_ctrl { 655 #ifdef CONFIG_KMAP_LOCAL 656 int idx; 657 pte_t pteval[KM_MAX_IDX]; 658 #endif 659 }; 660 661 struct task_struct { 662 #ifdef CONFIG_THREAD_INFO_IN_TASK 663 /* 664 * For reasons of header soup (see current_thread_info()), this 665 * must be the first element of task_struct. 666 */ 667 struct thread_info thread_info; 668 #endif 669 unsigned int __state; 670 671 /* 672 * This begins the randomizable portion of task_struct. Only 673 * scheduling-critical items should be added above here. 674 */ 675 randomized_struct_fields_start 676 677 void *stack; 678 refcount_t usage; 679 /* Per task flags (PF_*), defined further below: */ 680 unsigned int flags; 681 unsigned int ptrace; 682 683 #ifdef CONFIG_SMP 684 int on_cpu; 685 struct __call_single_node wake_entry; 686 #ifdef CONFIG_THREAD_INFO_IN_TASK 687 /* Current CPU: */ 688 unsigned int cpu; 689 #endif 690 unsigned int wakee_flips; 691 unsigned long wakee_flip_decay_ts; 692 struct task_struct *last_wakee; 693 694 /* 695 * recent_used_cpu is initially set as the last CPU used by a task 696 * that wakes affine another task. Waker/wakee relationships can 697 * push tasks around a CPU where each wakeup moves to the next one. 698 * Tracking a recently used CPU allows a quick search for a recently 699 * used CPU that may be idle. 700 */ 701 int recent_used_cpu; 702 int wake_cpu; 703 #endif 704 int on_rq; 705 706 int prio; 707 int static_prio; 708 int normal_prio; 709 unsigned int rt_priority; 710 711 const struct sched_class *sched_class; 712 struct sched_entity se; 713 struct sched_rt_entity rt; 714 struct sched_dl_entity dl; 715 716 #ifdef CONFIG_SCHED_CORE 717 struct rb_node core_node; 718 unsigned long core_cookie; 719 unsigned int core_occupation; 720 #endif 721 722 #ifdef CONFIG_CGROUP_SCHED 723 struct task_group *sched_task_group; 724 #endif 725 726 #ifdef CONFIG_UCLAMP_TASK 727 /* 728 * Clamp values requested for a scheduling entity. 729 * Must be updated with task_rq_lock() held. 730 */ 731 struct uclamp_se uclamp_req[UCLAMP_CNT]; 732 /* 733 * Effective clamp values used for a scheduling entity. 734 * Must be updated with task_rq_lock() held. 735 */ 736 struct uclamp_se uclamp[UCLAMP_CNT]; 737 #endif 738 739 #ifdef CONFIG_PREEMPT_NOTIFIERS 740 /* List of struct preempt_notifier: */ 741 struct hlist_head preempt_notifiers; 742 #endif 743 744 #ifdef CONFIG_BLK_DEV_IO_TRACE 745 unsigned int btrace_seq; 746 #endif 747 748 unsigned int policy; 749 int nr_cpus_allowed; 750 const cpumask_t *cpus_ptr; 751 cpumask_t cpus_mask; 752 void *migration_pending; 753 #ifdef CONFIG_SMP 754 unsigned short migration_disabled; 755 #endif 756 unsigned short migration_flags; 757 758 #ifdef CONFIG_PREEMPT_RCU 759 int rcu_read_lock_nesting; 760 union rcu_special rcu_read_unlock_special; 761 struct list_head rcu_node_entry; 762 struct rcu_node *rcu_blocked_node; 763 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 764 765 #ifdef CONFIG_TASKS_RCU 766 unsigned long rcu_tasks_nvcsw; 767 u8 rcu_tasks_holdout; 768 u8 rcu_tasks_idx; 769 int rcu_tasks_idle_cpu; 770 struct list_head rcu_tasks_holdout_list; 771 #endif /* #ifdef CONFIG_TASKS_RCU */ 772 773 #ifdef CONFIG_TASKS_TRACE_RCU 774 int trc_reader_nesting; 775 int trc_ipi_to_cpu; 776 union rcu_special trc_reader_special; 777 bool trc_reader_checked; 778 struct list_head trc_holdout_list; 779 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */ 780 781 struct sched_info sched_info; 782 783 struct list_head tasks; 784 #ifdef CONFIG_SMP 785 struct plist_node pushable_tasks; 786 struct rb_node pushable_dl_tasks; 787 #endif 788 789 struct mm_struct *mm; 790 struct mm_struct *active_mm; 791 792 /* Per-thread vma caching: */ 793 struct vmacache vmacache; 794 795 #ifdef SPLIT_RSS_COUNTING 796 struct task_rss_stat rss_stat; 797 #endif 798 int exit_state; 799 int exit_code; 800 int exit_signal; 801 /* The signal sent when the parent dies: */ 802 int pdeath_signal; 803 /* JOBCTL_*, siglock protected: */ 804 unsigned long jobctl; 805 806 /* Used for emulating ABI behavior of previous Linux versions: */ 807 unsigned int personality; 808 809 /* Scheduler bits, serialized by scheduler locks: */ 810 unsigned sched_reset_on_fork:1; 811 unsigned sched_contributes_to_load:1; 812 unsigned sched_migrated:1; 813 #ifdef CONFIG_PSI 814 unsigned sched_psi_wake_requeue:1; 815 #endif 816 817 /* Force alignment to the next boundary: */ 818 unsigned :0; 819 820 /* Unserialized, strictly 'current' */ 821 822 /* 823 * This field must not be in the scheduler word above due to wakelist 824 * queueing no longer being serialized by p->on_cpu. However: 825 * 826 * p->XXX = X; ttwu() 827 * schedule() if (p->on_rq && ..) // false 828 * smp_mb__after_spinlock(); if (smp_load_acquire(&p->on_cpu) && //true 829 * deactivate_task() ttwu_queue_wakelist()) 830 * p->on_rq = 0; p->sched_remote_wakeup = Y; 831 * 832 * guarantees all stores of 'current' are visible before 833 * ->sched_remote_wakeup gets used, so it can be in this word. 834 */ 835 unsigned sched_remote_wakeup:1; 836 837 /* Bit to tell LSMs we're in execve(): */ 838 unsigned in_execve:1; 839 unsigned in_iowait:1; 840 #ifndef TIF_RESTORE_SIGMASK 841 unsigned restore_sigmask:1; 842 #endif 843 #ifdef CONFIG_MEMCG 844 unsigned in_user_fault:1; 845 #endif 846 #ifdef CONFIG_COMPAT_BRK 847 unsigned brk_randomized:1; 848 #endif 849 #ifdef CONFIG_CGROUPS 850 /* disallow userland-initiated cgroup migration */ 851 unsigned no_cgroup_migration:1; 852 /* task is frozen/stopped (used by the cgroup freezer) */ 853 unsigned frozen:1; 854 #endif 855 #ifdef CONFIG_BLK_CGROUP 856 unsigned use_memdelay:1; 857 #endif 858 #ifdef CONFIG_PSI 859 /* Stalled due to lack of memory */ 860 unsigned in_memstall:1; 861 #endif 862 #ifdef CONFIG_PAGE_OWNER 863 /* Used by page_owner=on to detect recursion in page tracking. */ 864 unsigned in_page_owner:1; 865 #endif 866 867 unsigned long atomic_flags; /* Flags requiring atomic access. */ 868 869 struct restart_block restart_block; 870 871 pid_t pid; 872 pid_t tgid; 873 874 #ifdef CONFIG_STACKPROTECTOR 875 /* Canary value for the -fstack-protector GCC feature: */ 876 unsigned long stack_canary; 877 #endif 878 /* 879 * Pointers to the (original) parent process, youngest child, younger sibling, 880 * older sibling, respectively. (p->father can be replaced with 881 * p->real_parent->pid) 882 */ 883 884 /* Real parent process: */ 885 struct task_struct __rcu *real_parent; 886 887 /* Recipient of SIGCHLD, wait4() reports: */ 888 struct task_struct __rcu *parent; 889 890 /* 891 * Children/sibling form the list of natural children: 892 */ 893 struct list_head children; 894 struct list_head sibling; 895 struct task_struct *group_leader; 896 897 /* 898 * 'ptraced' is the list of tasks this task is using ptrace() on. 899 * 900 * This includes both natural children and PTRACE_ATTACH targets. 901 * 'ptrace_entry' is this task's link on the p->parent->ptraced list. 902 */ 903 struct list_head ptraced; 904 struct list_head ptrace_entry; 905 906 /* PID/PID hash table linkage. */ 907 struct pid *thread_pid; 908 struct hlist_node pid_links[PIDTYPE_MAX]; 909 struct list_head thread_group; 910 struct list_head thread_node; 911 912 struct completion *vfork_done; 913 914 /* CLONE_CHILD_SETTID: */ 915 int __user *set_child_tid; 916 917 /* CLONE_CHILD_CLEARTID: */ 918 int __user *clear_child_tid; 919 920 /* PF_IO_WORKER */ 921 void *pf_io_worker; 922 923 u64 utime; 924 u64 stime; 925 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME 926 u64 utimescaled; 927 u64 stimescaled; 928 #endif 929 u64 gtime; 930 struct prev_cputime prev_cputime; 931 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 932 struct vtime vtime; 933 #endif 934 935 #ifdef CONFIG_NO_HZ_FULL 936 atomic_t tick_dep_mask; 937 #endif 938 /* Context switch counts: */ 939 unsigned long nvcsw; 940 unsigned long nivcsw; 941 942 /* Monotonic time in nsecs: */ 943 u64 start_time; 944 945 /* Boot based time in nsecs: */ 946 u64 start_boottime; 947 948 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */ 949 unsigned long min_flt; 950 unsigned long maj_flt; 951 952 /* Empty if CONFIG_POSIX_CPUTIMERS=n */ 953 struct posix_cputimers posix_cputimers; 954 955 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK 956 struct posix_cputimers_work posix_cputimers_work; 957 #endif 958 959 /* Process credentials: */ 960 961 /* Tracer's credentials at attach: */ 962 const struct cred __rcu *ptracer_cred; 963 964 /* Objective and real subjective task credentials (COW): */ 965 const struct cred __rcu *real_cred; 966 967 /* Effective (overridable) subjective task credentials (COW): */ 968 const struct cred __rcu *cred; 969 970 #ifdef CONFIG_KEYS 971 /* Cached requested key. */ 972 struct key *cached_requested_key; 973 #endif 974 975 /* 976 * executable name, excluding path. 977 * 978 * - normally initialized setup_new_exec() 979 * - access it with [gs]et_task_comm() 980 * - lock it with task_lock() 981 */ 982 char comm[TASK_COMM_LEN]; 983 984 struct nameidata *nameidata; 985 986 #ifdef CONFIG_SYSVIPC 987 struct sysv_sem sysvsem; 988 struct sysv_shm sysvshm; 989 #endif 990 #ifdef CONFIG_DETECT_HUNG_TASK 991 unsigned long last_switch_count; 992 unsigned long last_switch_time; 993 #endif 994 /* Filesystem information: */ 995 struct fs_struct *fs; 996 997 /* Open file information: */ 998 struct files_struct *files; 999 1000 #ifdef CONFIG_IO_URING 1001 struct io_uring_task *io_uring; 1002 #endif 1003 1004 /* Namespaces: */ 1005 struct nsproxy *nsproxy; 1006 1007 /* Signal handlers: */ 1008 struct signal_struct *signal; 1009 struct sighand_struct __rcu *sighand; 1010 sigset_t blocked; 1011 sigset_t real_blocked; 1012 /* Restored if set_restore_sigmask() was used: */ 1013 sigset_t saved_sigmask; 1014 struct sigpending pending; 1015 unsigned long sas_ss_sp; 1016 size_t sas_ss_size; 1017 unsigned int sas_ss_flags; 1018 1019 struct callback_head *task_works; 1020 1021 #ifdef CONFIG_AUDIT 1022 #ifdef CONFIG_AUDITSYSCALL 1023 struct audit_context *audit_context; 1024 #endif 1025 kuid_t loginuid; 1026 unsigned int sessionid; 1027 #endif 1028 struct seccomp seccomp; 1029 struct syscall_user_dispatch syscall_dispatch; 1030 1031 /* Thread group tracking: */ 1032 u64 parent_exec_id; 1033 u64 self_exec_id; 1034 1035 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */ 1036 spinlock_t alloc_lock; 1037 1038 /* Protection of the PI data structures: */ 1039 raw_spinlock_t pi_lock; 1040 1041 struct wake_q_node wake_q; 1042 1043 #ifdef CONFIG_RT_MUTEXES 1044 /* PI waiters blocked on a rt_mutex held by this task: */ 1045 struct rb_root_cached pi_waiters; 1046 /* Updated under owner's pi_lock and rq lock */ 1047 struct task_struct *pi_top_task; 1048 /* Deadlock detection and priority inheritance handling: */ 1049 struct rt_mutex_waiter *pi_blocked_on; 1050 #endif 1051 1052 #ifdef CONFIG_DEBUG_MUTEXES 1053 /* Mutex deadlock detection: */ 1054 struct mutex_waiter *blocked_on; 1055 #endif 1056 1057 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1058 int non_block_count; 1059 #endif 1060 1061 #ifdef CONFIG_TRACE_IRQFLAGS 1062 struct irqtrace_events irqtrace; 1063 unsigned int hardirq_threaded; 1064 u64 hardirq_chain_key; 1065 int softirqs_enabled; 1066 int softirq_context; 1067 int irq_config; 1068 #endif 1069 #ifdef CONFIG_PREEMPT_RT 1070 int softirq_disable_cnt; 1071 #endif 1072 1073 #ifdef CONFIG_LOCKDEP 1074 # define MAX_LOCK_DEPTH 48UL 1075 u64 curr_chain_key; 1076 int lockdep_depth; 1077 unsigned int lockdep_recursion; 1078 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1079 #endif 1080 1081 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP) 1082 unsigned int in_ubsan; 1083 #endif 1084 1085 /* Journalling filesystem info: */ 1086 void *journal_info; 1087 1088 /* Stacked block device info: */ 1089 struct bio_list *bio_list; 1090 1091 #ifdef CONFIG_BLOCK 1092 /* Stack plugging: */ 1093 struct blk_plug *plug; 1094 #endif 1095 1096 /* VM state: */ 1097 struct reclaim_state *reclaim_state; 1098 1099 struct backing_dev_info *backing_dev_info; 1100 1101 struct io_context *io_context; 1102 1103 #ifdef CONFIG_COMPACTION 1104 struct capture_control *capture_control; 1105 #endif 1106 /* Ptrace state: */ 1107 unsigned long ptrace_message; 1108 kernel_siginfo_t *last_siginfo; 1109 1110 struct task_io_accounting ioac; 1111 #ifdef CONFIG_PSI 1112 /* Pressure stall state */ 1113 unsigned int psi_flags; 1114 #endif 1115 #ifdef CONFIG_TASK_XACCT 1116 /* Accumulated RSS usage: */ 1117 u64 acct_rss_mem1; 1118 /* Accumulated virtual memory usage: */ 1119 u64 acct_vm_mem1; 1120 /* stime + utime since last update: */ 1121 u64 acct_timexpd; 1122 #endif 1123 #ifdef CONFIG_CPUSETS 1124 /* Protected by ->alloc_lock: */ 1125 nodemask_t mems_allowed; 1126 /* Sequence number to catch updates: */ 1127 seqcount_spinlock_t mems_allowed_seq; 1128 int cpuset_mem_spread_rotor; 1129 int cpuset_slab_spread_rotor; 1130 #endif 1131 #ifdef CONFIG_CGROUPS 1132 /* Control Group info protected by css_set_lock: */ 1133 struct css_set __rcu *cgroups; 1134 /* cg_list protected by css_set_lock and tsk->alloc_lock: */ 1135 struct list_head cg_list; 1136 #endif 1137 #ifdef CONFIG_X86_CPU_RESCTRL 1138 u32 closid; 1139 u32 rmid; 1140 #endif 1141 #ifdef CONFIG_FUTEX 1142 struct robust_list_head __user *robust_list; 1143 #ifdef CONFIG_COMPAT 1144 struct compat_robust_list_head __user *compat_robust_list; 1145 #endif 1146 struct list_head pi_state_list; 1147 struct futex_pi_state *pi_state_cache; 1148 struct mutex futex_exit_mutex; 1149 unsigned int futex_state; 1150 #endif 1151 #ifdef CONFIG_PERF_EVENTS 1152 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; 1153 struct mutex perf_event_mutex; 1154 struct list_head perf_event_list; 1155 #endif 1156 #ifdef CONFIG_DEBUG_PREEMPT 1157 unsigned long preempt_disable_ip; 1158 #endif 1159 #ifdef CONFIG_NUMA 1160 /* Protected by alloc_lock: */ 1161 struct mempolicy *mempolicy; 1162 short il_prev; 1163 short pref_node_fork; 1164 #endif 1165 #ifdef CONFIG_NUMA_BALANCING 1166 int numa_scan_seq; 1167 unsigned int numa_scan_period; 1168 unsigned int numa_scan_period_max; 1169 int numa_preferred_nid; 1170 unsigned long numa_migrate_retry; 1171 /* Migration stamp: */ 1172 u64 node_stamp; 1173 u64 last_task_numa_placement; 1174 u64 last_sum_exec_runtime; 1175 struct callback_head numa_work; 1176 1177 /* 1178 * This pointer is only modified for current in syscall and 1179 * pagefault context (and for tasks being destroyed), so it can be read 1180 * from any of the following contexts: 1181 * - RCU read-side critical section 1182 * - current->numa_group from everywhere 1183 * - task's runqueue locked, task not running 1184 */ 1185 struct numa_group __rcu *numa_group; 1186 1187 /* 1188 * numa_faults is an array split into four regions: 1189 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer 1190 * in this precise order. 1191 * 1192 * faults_memory: Exponential decaying average of faults on a per-node 1193 * basis. Scheduling placement decisions are made based on these 1194 * counts. The values remain static for the duration of a PTE scan. 1195 * faults_cpu: Track the nodes the process was running on when a NUMA 1196 * hinting fault was incurred. 1197 * faults_memory_buffer and faults_cpu_buffer: Record faults per node 1198 * during the current scan window. When the scan completes, the counts 1199 * in faults_memory and faults_cpu decay and these values are copied. 1200 */ 1201 unsigned long *numa_faults; 1202 unsigned long total_numa_faults; 1203 1204 /* 1205 * numa_faults_locality tracks if faults recorded during the last 1206 * scan window were remote/local or failed to migrate. The task scan 1207 * period is adapted based on the locality of the faults with different 1208 * weights depending on whether they were shared or private faults 1209 */ 1210 unsigned long numa_faults_locality[3]; 1211 1212 unsigned long numa_pages_migrated; 1213 #endif /* CONFIG_NUMA_BALANCING */ 1214 1215 #ifdef CONFIG_RSEQ 1216 struct rseq __user *rseq; 1217 u32 rseq_sig; 1218 /* 1219 * RmW on rseq_event_mask must be performed atomically 1220 * with respect to preemption. 1221 */ 1222 unsigned long rseq_event_mask; 1223 #endif 1224 1225 struct tlbflush_unmap_batch tlb_ubc; 1226 1227 union { 1228 refcount_t rcu_users; 1229 struct rcu_head rcu; 1230 }; 1231 1232 /* Cache last used pipe for splice(): */ 1233 struct pipe_inode_info *splice_pipe; 1234 1235 struct page_frag task_frag; 1236 1237 #ifdef CONFIG_TASK_DELAY_ACCT 1238 struct task_delay_info *delays; 1239 #endif 1240 1241 #ifdef CONFIG_FAULT_INJECTION 1242 int make_it_fail; 1243 unsigned int fail_nth; 1244 #endif 1245 /* 1246 * When (nr_dirtied >= nr_dirtied_pause), it's time to call 1247 * balance_dirty_pages() for a dirty throttling pause: 1248 */ 1249 int nr_dirtied; 1250 int nr_dirtied_pause; 1251 /* Start of a write-and-pause period: */ 1252 unsigned long dirty_paused_when; 1253 1254 #ifdef CONFIG_LATENCYTOP 1255 int latency_record_count; 1256 struct latency_record latency_record[LT_SAVECOUNT]; 1257 #endif 1258 /* 1259 * Time slack values; these are used to round up poll() and 1260 * select() etc timeout values. These are in nanoseconds. 1261 */ 1262 u64 timer_slack_ns; 1263 u64 default_timer_slack_ns; 1264 1265 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) 1266 unsigned int kasan_depth; 1267 #endif 1268 1269 #ifdef CONFIG_KCSAN 1270 struct kcsan_ctx kcsan_ctx; 1271 #ifdef CONFIG_TRACE_IRQFLAGS 1272 struct irqtrace_events kcsan_save_irqtrace; 1273 #endif 1274 #endif 1275 1276 #if IS_ENABLED(CONFIG_KUNIT) 1277 struct kunit *kunit_test; 1278 #endif 1279 1280 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1281 /* Index of current stored address in ret_stack: */ 1282 int curr_ret_stack; 1283 int curr_ret_depth; 1284 1285 /* Stack of return addresses for return function tracing: */ 1286 struct ftrace_ret_stack *ret_stack; 1287 1288 /* Timestamp for last schedule: */ 1289 unsigned long long ftrace_timestamp; 1290 1291 /* 1292 * Number of functions that haven't been traced 1293 * because of depth overrun: 1294 */ 1295 atomic_t trace_overrun; 1296 1297 /* Pause tracing: */ 1298 atomic_t tracing_graph_pause; 1299 #endif 1300 1301 #ifdef CONFIG_TRACING 1302 /* State flags for use by tracers: */ 1303 unsigned long trace; 1304 1305 /* Bitmask and counter of trace recursion: */ 1306 unsigned long trace_recursion; 1307 #endif /* CONFIG_TRACING */ 1308 1309 #ifdef CONFIG_KCOV 1310 /* See kernel/kcov.c for more details. */ 1311 1312 /* Coverage collection mode enabled for this task (0 if disabled): */ 1313 unsigned int kcov_mode; 1314 1315 /* Size of the kcov_area: */ 1316 unsigned int kcov_size; 1317 1318 /* Buffer for coverage collection: */ 1319 void *kcov_area; 1320 1321 /* KCOV descriptor wired with this task or NULL: */ 1322 struct kcov *kcov; 1323 1324 /* KCOV common handle for remote coverage collection: */ 1325 u64 kcov_handle; 1326 1327 /* KCOV sequence number: */ 1328 int kcov_sequence; 1329 1330 /* Collect coverage from softirq context: */ 1331 unsigned int kcov_softirq; 1332 #endif 1333 1334 #ifdef CONFIG_MEMCG 1335 struct mem_cgroup *memcg_in_oom; 1336 gfp_t memcg_oom_gfp_mask; 1337 int memcg_oom_order; 1338 1339 /* Number of pages to reclaim on returning to userland: */ 1340 unsigned int memcg_nr_pages_over_high; 1341 1342 /* Used by memcontrol for targeted memcg charge: */ 1343 struct mem_cgroup *active_memcg; 1344 #endif 1345 1346 #ifdef CONFIG_BLK_CGROUP 1347 struct request_queue *throttle_queue; 1348 #endif 1349 1350 #ifdef CONFIG_UPROBES 1351 struct uprobe_task *utask; 1352 #endif 1353 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1354 unsigned int sequential_io; 1355 unsigned int sequential_io_avg; 1356 #endif 1357 struct kmap_ctrl kmap_ctrl; 1358 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1359 unsigned long task_state_change; 1360 #endif 1361 int pagefault_disabled; 1362 #ifdef CONFIG_MMU 1363 struct task_struct *oom_reaper_list; 1364 #endif 1365 #ifdef CONFIG_VMAP_STACK 1366 struct vm_struct *stack_vm_area; 1367 #endif 1368 #ifdef CONFIG_THREAD_INFO_IN_TASK 1369 /* A live task holds one reference: */ 1370 refcount_t stack_refcount; 1371 #endif 1372 #ifdef CONFIG_LIVEPATCH 1373 int patch_state; 1374 #endif 1375 #ifdef CONFIG_SECURITY 1376 /* Used by LSM modules for access restriction: */ 1377 void *security; 1378 #endif 1379 #ifdef CONFIG_BPF_SYSCALL 1380 /* Used by BPF task local storage */ 1381 struct bpf_local_storage __rcu *bpf_storage; 1382 #endif 1383 1384 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK 1385 unsigned long lowest_stack; 1386 unsigned long prev_lowest_stack; 1387 #endif 1388 1389 #ifdef CONFIG_X86_MCE 1390 void __user *mce_vaddr; 1391 __u64 mce_kflags; 1392 u64 mce_addr; 1393 __u64 mce_ripv : 1, 1394 mce_whole_page : 1, 1395 __mce_reserved : 62; 1396 struct callback_head mce_kill_me; 1397 #endif 1398 1399 #ifdef CONFIG_KRETPROBES 1400 struct llist_head kretprobe_instances; 1401 #endif 1402 1403 /* 1404 * New fields for task_struct should be added above here, so that 1405 * they are included in the randomized portion of task_struct. 1406 */ 1407 randomized_struct_fields_end 1408 1409 /* CPU-specific state of this task: */ 1410 struct thread_struct thread; 1411 1412 /* 1413 * WARNING: on x86, 'thread_struct' contains a variable-sized 1414 * structure. It *MUST* be at the end of 'task_struct'. 1415 * 1416 * Do not put anything below here! 1417 */ 1418 }; 1419 1420 static inline struct pid *task_pid(struct task_struct *task) 1421 { 1422 return task->thread_pid; 1423 } 1424 1425 /* 1426 * the helpers to get the task's different pids as they are seen 1427 * from various namespaces 1428 * 1429 * task_xid_nr() : global id, i.e. the id seen from the init namespace; 1430 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of 1431 * current. 1432 * task_xid_nr_ns() : id seen from the ns specified; 1433 * 1434 * see also pid_nr() etc in include/linux/pid.h 1435 */ 1436 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, struct pid_namespace *ns); 1437 1438 static inline pid_t task_pid_nr(struct task_struct *tsk) 1439 { 1440 return tsk->pid; 1441 } 1442 1443 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) 1444 { 1445 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); 1446 } 1447 1448 static inline pid_t task_pid_vnr(struct task_struct *tsk) 1449 { 1450 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); 1451 } 1452 1453 1454 static inline pid_t task_tgid_nr(struct task_struct *tsk) 1455 { 1456 return tsk->tgid; 1457 } 1458 1459 /** 1460 * pid_alive - check that a task structure is not stale 1461 * @p: Task structure to be checked. 1462 * 1463 * Test if a process is not yet dead (at most zombie state) 1464 * If pid_alive fails, then pointers within the task structure 1465 * can be stale and must not be dereferenced. 1466 * 1467 * Return: 1 if the process is alive. 0 otherwise. 1468 */ 1469 static inline int pid_alive(const struct task_struct *p) 1470 { 1471 return p->thread_pid != NULL; 1472 } 1473 1474 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) 1475 { 1476 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); 1477 } 1478 1479 static inline pid_t task_pgrp_vnr(struct task_struct *tsk) 1480 { 1481 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); 1482 } 1483 1484 1485 static inline pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) 1486 { 1487 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); 1488 } 1489 1490 static inline pid_t task_session_vnr(struct task_struct *tsk) 1491 { 1492 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); 1493 } 1494 1495 static inline pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) 1496 { 1497 return __task_pid_nr_ns(tsk, PIDTYPE_TGID, ns); 1498 } 1499 1500 static inline pid_t task_tgid_vnr(struct task_struct *tsk) 1501 { 1502 return __task_pid_nr_ns(tsk, PIDTYPE_TGID, NULL); 1503 } 1504 1505 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns) 1506 { 1507 pid_t pid = 0; 1508 1509 rcu_read_lock(); 1510 if (pid_alive(tsk)) 1511 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns); 1512 rcu_read_unlock(); 1513 1514 return pid; 1515 } 1516 1517 static inline pid_t task_ppid_nr(const struct task_struct *tsk) 1518 { 1519 return task_ppid_nr_ns(tsk, &init_pid_ns); 1520 } 1521 1522 /* Obsolete, do not use: */ 1523 static inline pid_t task_pgrp_nr(struct task_struct *tsk) 1524 { 1525 return task_pgrp_nr_ns(tsk, &init_pid_ns); 1526 } 1527 1528 #define TASK_REPORT_IDLE (TASK_REPORT + 1) 1529 #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1) 1530 1531 static inline unsigned int task_state_index(struct task_struct *tsk) 1532 { 1533 unsigned int tsk_state = READ_ONCE(tsk->__state); 1534 unsigned int state = (tsk_state | tsk->exit_state) & TASK_REPORT; 1535 1536 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX); 1537 1538 if (tsk_state == TASK_IDLE) 1539 state = TASK_REPORT_IDLE; 1540 1541 return fls(state); 1542 } 1543 1544 static inline char task_index_to_char(unsigned int state) 1545 { 1546 static const char state_char[] = "RSDTtXZPI"; 1547 1548 BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1); 1549 1550 return state_char[state]; 1551 } 1552 1553 static inline char task_state_to_char(struct task_struct *tsk) 1554 { 1555 return task_index_to_char(task_state_index(tsk)); 1556 } 1557 1558 /** 1559 * is_global_init - check if a task structure is init. Since init 1560 * is free to have sub-threads we need to check tgid. 1561 * @tsk: Task structure to be checked. 1562 * 1563 * Check if a task structure is the first user space task the kernel created. 1564 * 1565 * Return: 1 if the task structure is init. 0 otherwise. 1566 */ 1567 static inline int is_global_init(struct task_struct *tsk) 1568 { 1569 return task_tgid_nr(tsk) == 1; 1570 } 1571 1572 extern struct pid *cad_pid; 1573 1574 /* 1575 * Per process flags 1576 */ 1577 #define PF_VCPU 0x00000001 /* I'm a virtual CPU */ 1578 #define PF_IDLE 0x00000002 /* I am an IDLE thread */ 1579 #define PF_EXITING 0x00000004 /* Getting shut down */ 1580 #define PF_IO_WORKER 0x00000010 /* Task is an IO worker */ 1581 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 1582 #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */ 1583 #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */ 1584 #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */ 1585 #define PF_DUMPCORE 0x00000200 /* Dumped core */ 1586 #define PF_SIGNALED 0x00000400 /* Killed by a signal */ 1587 #define PF_MEMALLOC 0x00000800 /* Allocating memory */ 1588 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */ 1589 #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */ 1590 #define PF_USED_ASYNC 0x00004000 /* Used async_schedule*(), used by module init */ 1591 #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */ 1592 #define PF_FROZEN 0x00010000 /* Frozen for system suspend */ 1593 #define PF_KSWAPD 0x00020000 /* I am kswapd */ 1594 #define PF_MEMALLOC_NOFS 0x00040000 /* All allocation requests will inherit GFP_NOFS */ 1595 #define PF_MEMALLOC_NOIO 0x00080000 /* All allocation requests will inherit GFP_NOIO */ 1596 #define PF_LOCAL_THROTTLE 0x00100000 /* Throttle writes only against the bdi I write to, 1597 * I am cleaning dirty pages from some other bdi. */ 1598 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 1599 #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */ 1600 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 1601 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */ 1602 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 1603 #define PF_MEMALLOC_PIN 0x10000000 /* Allocation context constrained to zones which allow long term pinning. */ 1604 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ 1605 #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */ 1606 1607 /* 1608 * Only the _current_ task can read/write to tsk->flags, but other 1609 * tasks can access tsk->flags in readonly mode for example 1610 * with tsk_used_math (like during threaded core dumping). 1611 * There is however an exception to this rule during ptrace 1612 * or during fork: the ptracer task is allowed to write to the 1613 * child->flags of its traced child (same goes for fork, the parent 1614 * can write to the child->flags), because we're guaranteed the 1615 * child is not running and in turn not changing child->flags 1616 * at the same time the parent does it. 1617 */ 1618 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1619 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1620 #define clear_used_math() clear_stopped_child_used_math(current) 1621 #define set_used_math() set_stopped_child_used_math(current) 1622 1623 #define conditional_stopped_child_used_math(condition, child) \ 1624 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1625 1626 #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current) 1627 1628 #define copy_to_stopped_child_used_math(child) \ 1629 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1630 1631 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1632 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1633 #define used_math() tsk_used_math(current) 1634 1635 static inline bool is_percpu_thread(void) 1636 { 1637 #ifdef CONFIG_SMP 1638 return (current->flags & PF_NO_SETAFFINITY) && 1639 (current->nr_cpus_allowed == 1); 1640 #else 1641 return true; 1642 #endif 1643 } 1644 1645 /* Per-process atomic flags. */ 1646 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */ 1647 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */ 1648 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */ 1649 #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */ 1650 #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/ 1651 #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */ 1652 #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */ 1653 #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */ 1654 1655 #define TASK_PFA_TEST(name, func) \ 1656 static inline bool task_##func(struct task_struct *p) \ 1657 { return test_bit(PFA_##name, &p->atomic_flags); } 1658 1659 #define TASK_PFA_SET(name, func) \ 1660 static inline void task_set_##func(struct task_struct *p) \ 1661 { set_bit(PFA_##name, &p->atomic_flags); } 1662 1663 #define TASK_PFA_CLEAR(name, func) \ 1664 static inline void task_clear_##func(struct task_struct *p) \ 1665 { clear_bit(PFA_##name, &p->atomic_flags); } 1666 1667 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs) 1668 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs) 1669 1670 TASK_PFA_TEST(SPREAD_PAGE, spread_page) 1671 TASK_PFA_SET(SPREAD_PAGE, spread_page) 1672 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page) 1673 1674 TASK_PFA_TEST(SPREAD_SLAB, spread_slab) 1675 TASK_PFA_SET(SPREAD_SLAB, spread_slab) 1676 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab) 1677 1678 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable) 1679 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable) 1680 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable) 1681 1682 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1683 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1684 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1685 1686 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1687 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1688 1689 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable) 1690 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable) 1691 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable) 1692 1693 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1694 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1695 1696 static inline void 1697 current_restore_flags(unsigned long orig_flags, unsigned long flags) 1698 { 1699 current->flags &= ~flags; 1700 current->flags |= orig_flags & flags; 1701 } 1702 1703 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 1704 extern int task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed); 1705 #ifdef CONFIG_SMP 1706 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask); 1707 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask); 1708 #else 1709 static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) 1710 { 1711 } 1712 static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask) 1713 { 1714 if (!cpumask_test_cpu(0, new_mask)) 1715 return -EINVAL; 1716 return 0; 1717 } 1718 #endif 1719 1720 extern int yield_to(struct task_struct *p, bool preempt); 1721 extern void set_user_nice(struct task_struct *p, long nice); 1722 extern int task_prio(const struct task_struct *p); 1723 1724 /** 1725 * task_nice - return the nice value of a given task. 1726 * @p: the task in question. 1727 * 1728 * Return: The nice value [ -20 ... 0 ... 19 ]. 1729 */ 1730 static inline int task_nice(const struct task_struct *p) 1731 { 1732 return PRIO_TO_NICE((p)->static_prio); 1733 } 1734 1735 extern int can_nice(const struct task_struct *p, const int nice); 1736 extern int task_curr(const struct task_struct *p); 1737 extern int idle_cpu(int cpu); 1738 extern int available_idle_cpu(int cpu); 1739 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *); 1740 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *); 1741 extern void sched_set_fifo(struct task_struct *p); 1742 extern void sched_set_fifo_low(struct task_struct *p); 1743 extern void sched_set_normal(struct task_struct *p, int nice); 1744 extern int sched_setattr(struct task_struct *, const struct sched_attr *); 1745 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *); 1746 extern struct task_struct *idle_task(int cpu); 1747 1748 /** 1749 * is_idle_task - is the specified task an idle task? 1750 * @p: the task in question. 1751 * 1752 * Return: 1 if @p is an idle task. 0 otherwise. 1753 */ 1754 static __always_inline bool is_idle_task(const struct task_struct *p) 1755 { 1756 return !!(p->flags & PF_IDLE); 1757 } 1758 1759 extern struct task_struct *curr_task(int cpu); 1760 extern void ia64_set_curr_task(int cpu, struct task_struct *p); 1761 1762 void yield(void); 1763 1764 union thread_union { 1765 #ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK 1766 struct task_struct task; 1767 #endif 1768 #ifndef CONFIG_THREAD_INFO_IN_TASK 1769 struct thread_info thread_info; 1770 #endif 1771 unsigned long stack[THREAD_SIZE/sizeof(long)]; 1772 }; 1773 1774 #ifndef CONFIG_THREAD_INFO_IN_TASK 1775 extern struct thread_info init_thread_info; 1776 #endif 1777 1778 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)]; 1779 1780 #ifdef CONFIG_THREAD_INFO_IN_TASK 1781 static inline struct thread_info *task_thread_info(struct task_struct *task) 1782 { 1783 return &task->thread_info; 1784 } 1785 #elif !defined(__HAVE_THREAD_FUNCTIONS) 1786 # define task_thread_info(task) ((struct thread_info *)(task)->stack) 1787 #endif 1788 1789 /* 1790 * find a task by one of its numerical ids 1791 * 1792 * find_task_by_pid_ns(): 1793 * finds a task by its pid in the specified namespace 1794 * find_task_by_vpid(): 1795 * finds a task by its virtual pid 1796 * 1797 * see also find_vpid() etc in include/linux/pid.h 1798 */ 1799 1800 extern struct task_struct *find_task_by_vpid(pid_t nr); 1801 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns); 1802 1803 /* 1804 * find a task by its virtual pid and get the task struct 1805 */ 1806 extern struct task_struct *find_get_task_by_vpid(pid_t nr); 1807 1808 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 1809 extern int wake_up_process(struct task_struct *tsk); 1810 extern void wake_up_new_task(struct task_struct *tsk); 1811 1812 #ifdef CONFIG_SMP 1813 extern void kick_process(struct task_struct *tsk); 1814 #else 1815 static inline void kick_process(struct task_struct *tsk) { } 1816 #endif 1817 1818 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); 1819 1820 static inline void set_task_comm(struct task_struct *tsk, const char *from) 1821 { 1822 __set_task_comm(tsk, from, false); 1823 } 1824 1825 extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk); 1826 #define get_task_comm(buf, tsk) ({ \ 1827 BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN); \ 1828 __get_task_comm(buf, sizeof(buf), tsk); \ 1829 }) 1830 1831 #ifdef CONFIG_SMP 1832 static __always_inline void scheduler_ipi(void) 1833 { 1834 /* 1835 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting 1836 * TIF_NEED_RESCHED remotely (for the first time) will also send 1837 * this IPI. 1838 */ 1839 preempt_fold_need_resched(); 1840 } 1841 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state); 1842 #else 1843 static inline void scheduler_ipi(void) { } 1844 static inline unsigned long wait_task_inactive(struct task_struct *p, unsigned int match_state) 1845 { 1846 return 1; 1847 } 1848 #endif 1849 1850 /* 1851 * Set thread flags in other task's structures. 1852 * See asm/thread_info.h for TIF_xxxx flags available: 1853 */ 1854 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 1855 { 1856 set_ti_thread_flag(task_thread_info(tsk), flag); 1857 } 1858 1859 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 1860 { 1861 clear_ti_thread_flag(task_thread_info(tsk), flag); 1862 } 1863 1864 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag, 1865 bool value) 1866 { 1867 update_ti_thread_flag(task_thread_info(tsk), flag, value); 1868 } 1869 1870 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 1871 { 1872 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 1873 } 1874 1875 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 1876 { 1877 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 1878 } 1879 1880 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 1881 { 1882 return test_ti_thread_flag(task_thread_info(tsk), flag); 1883 } 1884 1885 static inline void set_tsk_need_resched(struct task_struct *tsk) 1886 { 1887 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 1888 } 1889 1890 static inline void clear_tsk_need_resched(struct task_struct *tsk) 1891 { 1892 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 1893 } 1894 1895 static inline int test_tsk_need_resched(struct task_struct *tsk) 1896 { 1897 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 1898 } 1899 1900 /* 1901 * cond_resched() and cond_resched_lock(): latency reduction via 1902 * explicit rescheduling in places that are safe. The return 1903 * value indicates whether a reschedule was done in fact. 1904 * cond_resched_lock() will drop the spinlock before scheduling, 1905 */ 1906 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) 1907 extern int __cond_resched(void); 1908 1909 #ifdef CONFIG_PREEMPT_DYNAMIC 1910 1911 DECLARE_STATIC_CALL(cond_resched, __cond_resched); 1912 1913 static __always_inline int _cond_resched(void) 1914 { 1915 return static_call_mod(cond_resched)(); 1916 } 1917 1918 #else 1919 1920 static inline int _cond_resched(void) 1921 { 1922 return __cond_resched(); 1923 } 1924 1925 #endif /* CONFIG_PREEMPT_DYNAMIC */ 1926 1927 #else 1928 1929 static inline int _cond_resched(void) { return 0; } 1930 1931 #endif /* !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) */ 1932 1933 #define cond_resched() ({ \ 1934 ___might_sleep(__FILE__, __LINE__, 0); \ 1935 _cond_resched(); \ 1936 }) 1937 1938 extern int __cond_resched_lock(spinlock_t *lock); 1939 extern int __cond_resched_rwlock_read(rwlock_t *lock); 1940 extern int __cond_resched_rwlock_write(rwlock_t *lock); 1941 1942 #define cond_resched_lock(lock) ({ \ 1943 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\ 1944 __cond_resched_lock(lock); \ 1945 }) 1946 1947 #define cond_resched_rwlock_read(lock) ({ \ 1948 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \ 1949 __cond_resched_rwlock_read(lock); \ 1950 }) 1951 1952 #define cond_resched_rwlock_write(lock) ({ \ 1953 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \ 1954 __cond_resched_rwlock_write(lock); \ 1955 }) 1956 1957 static inline void cond_resched_rcu(void) 1958 { 1959 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) 1960 rcu_read_unlock(); 1961 cond_resched(); 1962 rcu_read_lock(); 1963 #endif 1964 } 1965 1966 /* 1967 * Does a critical section need to be broken due to another 1968 * task waiting?: (technically does not depend on CONFIG_PREEMPTION, 1969 * but a general need for low latency) 1970 */ 1971 static inline int spin_needbreak(spinlock_t *lock) 1972 { 1973 #ifdef CONFIG_PREEMPTION 1974 return spin_is_contended(lock); 1975 #else 1976 return 0; 1977 #endif 1978 } 1979 1980 /* 1981 * Check if a rwlock is contended. 1982 * Returns non-zero if there is another task waiting on the rwlock. 1983 * Returns zero if the lock is not contended or the system / underlying 1984 * rwlock implementation does not support contention detection. 1985 * Technically does not depend on CONFIG_PREEMPTION, but a general need 1986 * for low latency. 1987 */ 1988 static inline int rwlock_needbreak(rwlock_t *lock) 1989 { 1990 #ifdef CONFIG_PREEMPTION 1991 return rwlock_is_contended(lock); 1992 #else 1993 return 0; 1994 #endif 1995 } 1996 1997 static __always_inline bool need_resched(void) 1998 { 1999 return unlikely(tif_need_resched()); 2000 } 2001 2002 /* 2003 * Wrappers for p->thread_info->cpu access. No-op on UP. 2004 */ 2005 #ifdef CONFIG_SMP 2006 2007 static inline unsigned int task_cpu(const struct task_struct *p) 2008 { 2009 #ifdef CONFIG_THREAD_INFO_IN_TASK 2010 return READ_ONCE(p->cpu); 2011 #else 2012 return READ_ONCE(task_thread_info(p)->cpu); 2013 #endif 2014 } 2015 2016 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 2017 2018 #else 2019 2020 static inline unsigned int task_cpu(const struct task_struct *p) 2021 { 2022 return 0; 2023 } 2024 2025 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 2026 { 2027 } 2028 2029 #endif /* CONFIG_SMP */ 2030 2031 extern bool sched_task_on_rq(struct task_struct *p); 2032 2033 /* 2034 * In order to reduce various lock holder preemption latencies provide an 2035 * interface to see if a vCPU is currently running or not. 2036 * 2037 * This allows us to terminate optimistic spin loops and block, analogous to 2038 * the native optimistic spin heuristic of testing if the lock owner task is 2039 * running or not. 2040 */ 2041 #ifndef vcpu_is_preempted 2042 static inline bool vcpu_is_preempted(int cpu) 2043 { 2044 return false; 2045 } 2046 #endif 2047 2048 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 2049 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 2050 2051 #ifndef TASK_SIZE_OF 2052 #define TASK_SIZE_OF(tsk) TASK_SIZE 2053 #endif 2054 2055 #ifdef CONFIG_SMP 2056 /* Returns effective CPU energy utilization, as seen by the scheduler */ 2057 unsigned long sched_cpu_util(int cpu, unsigned long max); 2058 #endif /* CONFIG_SMP */ 2059 2060 #ifdef CONFIG_RSEQ 2061 2062 /* 2063 * Map the event mask on the user-space ABI enum rseq_cs_flags 2064 * for direct mask checks. 2065 */ 2066 enum rseq_event_mask_bits { 2067 RSEQ_EVENT_PREEMPT_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT, 2068 RSEQ_EVENT_SIGNAL_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT, 2069 RSEQ_EVENT_MIGRATE_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT, 2070 }; 2071 2072 enum rseq_event_mask { 2073 RSEQ_EVENT_PREEMPT = (1U << RSEQ_EVENT_PREEMPT_BIT), 2074 RSEQ_EVENT_SIGNAL = (1U << RSEQ_EVENT_SIGNAL_BIT), 2075 RSEQ_EVENT_MIGRATE = (1U << RSEQ_EVENT_MIGRATE_BIT), 2076 }; 2077 2078 static inline void rseq_set_notify_resume(struct task_struct *t) 2079 { 2080 if (t->rseq) 2081 set_tsk_thread_flag(t, TIF_NOTIFY_RESUME); 2082 } 2083 2084 void __rseq_handle_notify_resume(struct ksignal *sig, struct pt_regs *regs); 2085 2086 static inline void rseq_handle_notify_resume(struct ksignal *ksig, 2087 struct pt_regs *regs) 2088 { 2089 if (current->rseq) 2090 __rseq_handle_notify_resume(ksig, regs); 2091 } 2092 2093 static inline void rseq_signal_deliver(struct ksignal *ksig, 2094 struct pt_regs *regs) 2095 { 2096 preempt_disable(); 2097 __set_bit(RSEQ_EVENT_SIGNAL_BIT, ¤t->rseq_event_mask); 2098 preempt_enable(); 2099 rseq_handle_notify_resume(ksig, regs); 2100 } 2101 2102 /* rseq_preempt() requires preemption to be disabled. */ 2103 static inline void rseq_preempt(struct task_struct *t) 2104 { 2105 __set_bit(RSEQ_EVENT_PREEMPT_BIT, &t->rseq_event_mask); 2106 rseq_set_notify_resume(t); 2107 } 2108 2109 /* rseq_migrate() requires preemption to be disabled. */ 2110 static inline void rseq_migrate(struct task_struct *t) 2111 { 2112 __set_bit(RSEQ_EVENT_MIGRATE_BIT, &t->rseq_event_mask); 2113 rseq_set_notify_resume(t); 2114 } 2115 2116 /* 2117 * If parent process has a registered restartable sequences area, the 2118 * child inherits. Unregister rseq for a clone with CLONE_VM set. 2119 */ 2120 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags) 2121 { 2122 if (clone_flags & CLONE_VM) { 2123 t->rseq = NULL; 2124 t->rseq_sig = 0; 2125 t->rseq_event_mask = 0; 2126 } else { 2127 t->rseq = current->rseq; 2128 t->rseq_sig = current->rseq_sig; 2129 t->rseq_event_mask = current->rseq_event_mask; 2130 } 2131 } 2132 2133 static inline void rseq_execve(struct task_struct *t) 2134 { 2135 t->rseq = NULL; 2136 t->rseq_sig = 0; 2137 t->rseq_event_mask = 0; 2138 } 2139 2140 #else 2141 2142 static inline void rseq_set_notify_resume(struct task_struct *t) 2143 { 2144 } 2145 static inline void rseq_handle_notify_resume(struct ksignal *ksig, 2146 struct pt_regs *regs) 2147 { 2148 } 2149 static inline void rseq_signal_deliver(struct ksignal *ksig, 2150 struct pt_regs *regs) 2151 { 2152 } 2153 static inline void rseq_preempt(struct task_struct *t) 2154 { 2155 } 2156 static inline void rseq_migrate(struct task_struct *t) 2157 { 2158 } 2159 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags) 2160 { 2161 } 2162 static inline void rseq_execve(struct task_struct *t) 2163 { 2164 } 2165 2166 #endif 2167 2168 #ifdef CONFIG_DEBUG_RSEQ 2169 2170 void rseq_syscall(struct pt_regs *regs); 2171 2172 #else 2173 2174 static inline void rseq_syscall(struct pt_regs *regs) 2175 { 2176 } 2177 2178 #endif 2179 2180 const struct sched_avg *sched_trace_cfs_rq_avg(struct cfs_rq *cfs_rq); 2181 char *sched_trace_cfs_rq_path(struct cfs_rq *cfs_rq, char *str, int len); 2182 int sched_trace_cfs_rq_cpu(struct cfs_rq *cfs_rq); 2183 2184 const struct sched_avg *sched_trace_rq_avg_rt(struct rq *rq); 2185 const struct sched_avg *sched_trace_rq_avg_dl(struct rq *rq); 2186 const struct sched_avg *sched_trace_rq_avg_irq(struct rq *rq); 2187 2188 int sched_trace_rq_cpu(struct rq *rq); 2189 int sched_trace_rq_cpu_capacity(struct rq *rq); 2190 int sched_trace_rq_nr_running(struct rq *rq); 2191 2192 const struct cpumask *sched_trace_rd_span(struct root_domain *rd); 2193 2194 #ifdef CONFIG_SCHED_CORE 2195 extern void sched_core_free(struct task_struct *tsk); 2196 extern void sched_core_fork(struct task_struct *p); 2197 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type, 2198 unsigned long uaddr); 2199 #else 2200 static inline void sched_core_free(struct task_struct *tsk) { } 2201 static inline void sched_core_fork(struct task_struct *p) { } 2202 #endif 2203 2204 #endif 2205