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 bpf_run_ctx; 46 struct capture_control; 47 struct cfs_rq; 48 struct fs_struct; 49 struct futex_pi_state; 50 struct io_context; 51 struct io_uring_task; 52 struct mempolicy; 53 struct nameidata; 54 struct nsproxy; 55 struct perf_event_context; 56 struct pid_namespace; 57 struct pipe_inode_info; 58 struct rcu_node; 59 struct reclaim_state; 60 struct robust_list_head; 61 struct root_domain; 62 struct rq; 63 struct sched_attr; 64 struct sched_param; 65 struct seq_file; 66 struct sighand_struct; 67 struct signal_struct; 68 struct task_delay_info; 69 struct task_group; 70 71 /* 72 * Task state bitmask. NOTE! These bits are also 73 * encoded in fs/proc/array.c: get_task_state(). 74 * 75 * We have two separate sets of flags: task->state 76 * is about runnability, while task->exit_state are 77 * about the task exiting. Confusing, but this way 78 * modifying one set can't modify the other one by 79 * mistake. 80 */ 81 82 /* Used in tsk->state: */ 83 #define TASK_RUNNING 0x0000 84 #define TASK_INTERRUPTIBLE 0x0001 85 #define TASK_UNINTERRUPTIBLE 0x0002 86 #define __TASK_STOPPED 0x0004 87 #define __TASK_TRACED 0x0008 88 /* Used in tsk->exit_state: */ 89 #define EXIT_DEAD 0x0010 90 #define EXIT_ZOMBIE 0x0020 91 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD) 92 /* Used in tsk->state again: */ 93 #define TASK_PARKED 0x0040 94 #define TASK_DEAD 0x0080 95 #define TASK_WAKEKILL 0x0100 96 #define TASK_WAKING 0x0200 97 #define TASK_NOLOAD 0x0400 98 #define TASK_NEW 0x0800 99 #define TASK_STATE_MAX 0x1000 100 101 /* Convenience macros for the sake of set_current_state: */ 102 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 103 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 104 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED) 105 106 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD) 107 108 /* Convenience macros for the sake of wake_up(): */ 109 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 110 111 /* get_task_state(): */ 112 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 113 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 114 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \ 115 TASK_PARKED) 116 117 #define task_is_running(task) (READ_ONCE((task)->__state) == TASK_RUNNING) 118 119 #define task_is_traced(task) ((READ_ONCE(task->__state) & __TASK_TRACED) != 0) 120 121 #define task_is_stopped(task) ((READ_ONCE(task->__state) & __TASK_STOPPED) != 0) 122 123 #define task_is_stopped_or_traced(task) ((READ_ONCE(task->__state) & (__TASK_STOPPED | __TASK_TRACED)) != 0) 124 125 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 126 127 /* 128 * Special states are those that do not use the normal wait-loop pattern. See 129 * the comment with set_special_state(). 130 */ 131 #define is_special_task_state(state) \ 132 ((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD)) 133 134 #define __set_current_state(state_value) \ 135 do { \ 136 WARN_ON_ONCE(is_special_task_state(state_value));\ 137 current->task_state_change = _THIS_IP_; \ 138 WRITE_ONCE(current->__state, (state_value)); \ 139 } while (0) 140 141 #define set_current_state(state_value) \ 142 do { \ 143 WARN_ON_ONCE(is_special_task_state(state_value));\ 144 current->task_state_change = _THIS_IP_; \ 145 smp_store_mb(current->__state, (state_value)); \ 146 } while (0) 147 148 #define set_special_state(state_value) \ 149 do { \ 150 unsigned long flags; /* may shadow */ \ 151 WARN_ON_ONCE(!is_special_task_state(state_value)); \ 152 raw_spin_lock_irqsave(¤t->pi_lock, flags); \ 153 current->task_state_change = _THIS_IP_; \ 154 WRITE_ONCE(current->__state, (state_value)); \ 155 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \ 156 } while (0) 157 #else 158 /* 159 * set_current_state() includes a barrier so that the write of current->state 160 * is correctly serialised wrt the caller's subsequent test of whether to 161 * actually sleep: 162 * 163 * for (;;) { 164 * set_current_state(TASK_UNINTERRUPTIBLE); 165 * if (CONDITION) 166 * break; 167 * 168 * schedule(); 169 * } 170 * __set_current_state(TASK_RUNNING); 171 * 172 * If the caller does not need such serialisation (because, for instance, the 173 * CONDITION test and condition change and wakeup are under the same lock) then 174 * use __set_current_state(). 175 * 176 * The above is typically ordered against the wakeup, which does: 177 * 178 * CONDITION = 1; 179 * wake_up_state(p, TASK_UNINTERRUPTIBLE); 180 * 181 * where wake_up_state()/try_to_wake_up() executes a full memory barrier before 182 * accessing p->state. 183 * 184 * Wakeup will do: if (@state & p->state) p->state = TASK_RUNNING, that is, 185 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a 186 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING). 187 * 188 * However, with slightly different timing the wakeup TASK_RUNNING store can 189 * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not 190 * a problem either because that will result in one extra go around the loop 191 * and our @cond test will save the day. 192 * 193 * Also see the comments of try_to_wake_up(). 194 */ 195 #define __set_current_state(state_value) \ 196 WRITE_ONCE(current->__state, (state_value)) 197 198 #define set_current_state(state_value) \ 199 smp_store_mb(current->__state, (state_value)) 200 201 /* 202 * set_special_state() should be used for those states when the blocking task 203 * can not use the regular condition based wait-loop. In that case we must 204 * serialize against wakeups such that any possible in-flight TASK_RUNNING stores 205 * will not collide with our state change. 206 */ 207 #define set_special_state(state_value) \ 208 do { \ 209 unsigned long flags; /* may shadow */ \ 210 raw_spin_lock_irqsave(¤t->pi_lock, flags); \ 211 WRITE_ONCE(current->__state, (state_value)); \ 212 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \ 213 } while (0) 214 215 #endif 216 217 #define get_current_state() READ_ONCE(current->__state) 218 219 /* Task command name length: */ 220 #define TASK_COMM_LEN 16 221 222 extern void scheduler_tick(void); 223 224 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 225 226 extern long schedule_timeout(long timeout); 227 extern long schedule_timeout_interruptible(long timeout); 228 extern long schedule_timeout_killable(long timeout); 229 extern long schedule_timeout_uninterruptible(long timeout); 230 extern long schedule_timeout_idle(long timeout); 231 asmlinkage void schedule(void); 232 extern void schedule_preempt_disabled(void); 233 asmlinkage void preempt_schedule_irq(void); 234 235 extern int __must_check io_schedule_prepare(void); 236 extern void io_schedule_finish(int token); 237 extern long io_schedule_timeout(long timeout); 238 extern void io_schedule(void); 239 240 /** 241 * struct prev_cputime - snapshot of system and user cputime 242 * @utime: time spent in user mode 243 * @stime: time spent in system mode 244 * @lock: protects the above two fields 245 * 246 * Stores previous user/system time values such that we can guarantee 247 * monotonicity. 248 */ 249 struct prev_cputime { 250 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 251 u64 utime; 252 u64 stime; 253 raw_spinlock_t lock; 254 #endif 255 }; 256 257 enum vtime_state { 258 /* Task is sleeping or running in a CPU with VTIME inactive: */ 259 VTIME_INACTIVE = 0, 260 /* Task is idle */ 261 VTIME_IDLE, 262 /* Task runs in kernelspace in a CPU with VTIME active: */ 263 VTIME_SYS, 264 /* Task runs in userspace in a CPU with VTIME active: */ 265 VTIME_USER, 266 /* Task runs as guests in a CPU with VTIME active: */ 267 VTIME_GUEST, 268 }; 269 270 struct vtime { 271 seqcount_t seqcount; 272 unsigned long long starttime; 273 enum vtime_state state; 274 unsigned int cpu; 275 u64 utime; 276 u64 stime; 277 u64 gtime; 278 }; 279 280 /* 281 * Utilization clamp constraints. 282 * @UCLAMP_MIN: Minimum utilization 283 * @UCLAMP_MAX: Maximum utilization 284 * @UCLAMP_CNT: Utilization clamp constraints count 285 */ 286 enum uclamp_id { 287 UCLAMP_MIN = 0, 288 UCLAMP_MAX, 289 UCLAMP_CNT 290 }; 291 292 #ifdef CONFIG_SMP 293 extern struct root_domain def_root_domain; 294 extern struct mutex sched_domains_mutex; 295 #endif 296 297 struct sched_info { 298 #ifdef CONFIG_SCHED_INFO 299 /* Cumulative counters: */ 300 301 /* # of times we have run on this CPU: */ 302 unsigned long pcount; 303 304 /* Time spent waiting on a runqueue: */ 305 unsigned long long run_delay; 306 307 /* Timestamps: */ 308 309 /* When did we last run on a CPU? */ 310 unsigned long long last_arrival; 311 312 /* When were we last queued to run? */ 313 unsigned long long last_queued; 314 315 #endif /* CONFIG_SCHED_INFO */ 316 }; 317 318 /* 319 * Integer metrics need fixed point arithmetic, e.g., sched/fair 320 * has a few: load, load_avg, util_avg, freq, and capacity. 321 * 322 * We define a basic fixed point arithmetic range, and then formalize 323 * all these metrics based on that basic range. 324 */ 325 # define SCHED_FIXEDPOINT_SHIFT 10 326 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT) 327 328 /* Increase resolution of cpu_capacity calculations */ 329 # define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT 330 # define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) 331 332 struct load_weight { 333 unsigned long weight; 334 u32 inv_weight; 335 }; 336 337 /** 338 * struct util_est - Estimation utilization of FAIR tasks 339 * @enqueued: instantaneous estimated utilization of a task/cpu 340 * @ewma: the Exponential Weighted Moving Average (EWMA) 341 * utilization of a task 342 * 343 * Support data structure to track an Exponential Weighted Moving Average 344 * (EWMA) of a FAIR task's utilization. New samples are added to the moving 345 * average each time a task completes an activation. Sample's weight is chosen 346 * so that the EWMA will be relatively insensitive to transient changes to the 347 * task's workload. 348 * 349 * The enqueued attribute has a slightly different meaning for tasks and cpus: 350 * - task: the task's util_avg at last task dequeue time 351 * - cfs_rq: the sum of util_est.enqueued for each RUNNABLE task on that CPU 352 * Thus, the util_est.enqueued of a task represents the contribution on the 353 * estimated utilization of the CPU where that task is currently enqueued. 354 * 355 * Only for tasks we track a moving average of the past instantaneous 356 * estimated utilization. This allows to absorb sporadic drops in utilization 357 * of an otherwise almost periodic task. 358 * 359 * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg 360 * updates. When a task is dequeued, its util_est should not be updated if its 361 * util_avg has not been updated in the meantime. 362 * This information is mapped into the MSB bit of util_est.enqueued at dequeue 363 * time. Since max value of util_est.enqueued for a task is 1024 (PELT util_avg 364 * for a task) it is safe to use MSB. 365 */ 366 struct util_est { 367 unsigned int enqueued; 368 unsigned int ewma; 369 #define UTIL_EST_WEIGHT_SHIFT 2 370 #define UTIL_AVG_UNCHANGED 0x80000000 371 } __attribute__((__aligned__(sizeof(u64)))); 372 373 /* 374 * The load/runnable/util_avg accumulates an infinite geometric series 375 * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c). 376 * 377 * [load_avg definition] 378 * 379 * load_avg = runnable% * scale_load_down(load) 380 * 381 * [runnable_avg definition] 382 * 383 * runnable_avg = runnable% * SCHED_CAPACITY_SCALE 384 * 385 * [util_avg definition] 386 * 387 * util_avg = running% * SCHED_CAPACITY_SCALE 388 * 389 * where runnable% is the time ratio that a sched_entity is runnable and 390 * running% the time ratio that a sched_entity is running. 391 * 392 * For cfs_rq, they are the aggregated values of all runnable and blocked 393 * sched_entities. 394 * 395 * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU 396 * capacity scaling. The scaling is done through the rq_clock_pelt that is used 397 * for computing those signals (see update_rq_clock_pelt()) 398 * 399 * N.B., the above ratios (runnable% and running%) themselves are in the 400 * range of [0, 1]. To do fixed point arithmetics, we therefore scale them 401 * to as large a range as necessary. This is for example reflected by 402 * util_avg's SCHED_CAPACITY_SCALE. 403 * 404 * [Overflow issue] 405 * 406 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities 407 * with the highest load (=88761), always runnable on a single cfs_rq, 408 * and should not overflow as the number already hits PID_MAX_LIMIT. 409 * 410 * For all other cases (including 32-bit kernels), struct load_weight's 411 * weight will overflow first before we do, because: 412 * 413 * Max(load_avg) <= Max(load.weight) 414 * 415 * Then it is the load_weight's responsibility to consider overflow 416 * issues. 417 */ 418 struct sched_avg { 419 u64 last_update_time; 420 u64 load_sum; 421 u64 runnable_sum; 422 u32 util_sum; 423 u32 period_contrib; 424 unsigned long load_avg; 425 unsigned long runnable_avg; 426 unsigned long util_avg; 427 struct util_est util_est; 428 } ____cacheline_aligned; 429 430 struct sched_statistics { 431 #ifdef CONFIG_SCHEDSTATS 432 u64 wait_start; 433 u64 wait_max; 434 u64 wait_count; 435 u64 wait_sum; 436 u64 iowait_count; 437 u64 iowait_sum; 438 439 u64 sleep_start; 440 u64 sleep_max; 441 s64 sum_sleep_runtime; 442 443 u64 block_start; 444 u64 block_max; 445 u64 exec_max; 446 u64 slice_max; 447 448 u64 nr_migrations_cold; 449 u64 nr_failed_migrations_affine; 450 u64 nr_failed_migrations_running; 451 u64 nr_failed_migrations_hot; 452 u64 nr_forced_migrations; 453 454 u64 nr_wakeups; 455 u64 nr_wakeups_sync; 456 u64 nr_wakeups_migrate; 457 u64 nr_wakeups_local; 458 u64 nr_wakeups_remote; 459 u64 nr_wakeups_affine; 460 u64 nr_wakeups_affine_attempts; 461 u64 nr_wakeups_passive; 462 u64 nr_wakeups_idle; 463 #endif 464 }; 465 466 struct sched_entity { 467 /* For load-balancing: */ 468 struct load_weight load; 469 struct rb_node run_node; 470 struct list_head group_node; 471 unsigned int on_rq; 472 473 u64 exec_start; 474 u64 sum_exec_runtime; 475 u64 vruntime; 476 u64 prev_sum_exec_runtime; 477 478 u64 nr_migrations; 479 480 struct sched_statistics statistics; 481 482 #ifdef CONFIG_FAIR_GROUP_SCHED 483 int depth; 484 struct sched_entity *parent; 485 /* rq on which this entity is (to be) queued: */ 486 struct cfs_rq *cfs_rq; 487 /* rq "owned" by this entity/group: */ 488 struct cfs_rq *my_q; 489 /* cached value of my_q->h_nr_running */ 490 unsigned long runnable_weight; 491 #endif 492 493 #ifdef CONFIG_SMP 494 /* 495 * Per entity load average tracking. 496 * 497 * Put into separate cache line so it does not 498 * collide with read-mostly values above. 499 */ 500 struct sched_avg avg; 501 #endif 502 }; 503 504 struct sched_rt_entity { 505 struct list_head run_list; 506 unsigned long timeout; 507 unsigned long watchdog_stamp; 508 unsigned int time_slice; 509 unsigned short on_rq; 510 unsigned short on_list; 511 512 struct sched_rt_entity *back; 513 #ifdef CONFIG_RT_GROUP_SCHED 514 struct sched_rt_entity *parent; 515 /* rq on which this entity is (to be) queued: */ 516 struct rt_rq *rt_rq; 517 /* rq "owned" by this entity/group: */ 518 struct rt_rq *my_q; 519 #endif 520 } __randomize_layout; 521 522 struct sched_dl_entity { 523 struct rb_node rb_node; 524 525 /* 526 * Original scheduling parameters. Copied here from sched_attr 527 * during sched_setattr(), they will remain the same until 528 * the next sched_setattr(). 529 */ 530 u64 dl_runtime; /* Maximum runtime for each instance */ 531 u64 dl_deadline; /* Relative deadline of each instance */ 532 u64 dl_period; /* Separation of two instances (period) */ 533 u64 dl_bw; /* dl_runtime / dl_period */ 534 u64 dl_density; /* dl_runtime / dl_deadline */ 535 536 /* 537 * Actual scheduling parameters. Initialized with the values above, 538 * they are continuously updated during task execution. Note that 539 * the remaining runtime could be < 0 in case we are in overrun. 540 */ 541 s64 runtime; /* Remaining runtime for this instance */ 542 u64 deadline; /* Absolute deadline for this instance */ 543 unsigned int flags; /* Specifying the scheduler behaviour */ 544 545 /* 546 * Some bool flags: 547 * 548 * @dl_throttled tells if we exhausted the runtime. If so, the 549 * task has to wait for a replenishment to be performed at the 550 * next firing of dl_timer. 551 * 552 * @dl_boosted tells if we are boosted due to DI. If so we are 553 * outside bandwidth enforcement mechanism (but only until we 554 * exit the critical section); 555 * 556 * @dl_yielded tells if task gave up the CPU before consuming 557 * all its available runtime during the last job. 558 * 559 * @dl_non_contending tells if the task is inactive while still 560 * contributing to the active utilization. In other words, it 561 * indicates if the inactive timer has been armed and its handler 562 * has not been executed yet. This flag is useful to avoid race 563 * conditions between the inactive timer handler and the wakeup 564 * code. 565 * 566 * @dl_overrun tells if the task asked to be informed about runtime 567 * overruns. 568 */ 569 unsigned int dl_throttled : 1; 570 unsigned int dl_yielded : 1; 571 unsigned int dl_non_contending : 1; 572 unsigned int dl_overrun : 1; 573 574 /* 575 * Bandwidth enforcement timer. Each -deadline task has its 576 * own bandwidth to be enforced, thus we need one timer per task. 577 */ 578 struct hrtimer dl_timer; 579 580 /* 581 * Inactive timer, responsible for decreasing the active utilization 582 * at the "0-lag time". When a -deadline task blocks, it contributes 583 * to GRUB's active utilization until the "0-lag time", hence a 584 * timer is needed to decrease the active utilization at the correct 585 * time. 586 */ 587 struct hrtimer inactive_timer; 588 589 #ifdef CONFIG_RT_MUTEXES 590 /* 591 * Priority Inheritance. When a DEADLINE scheduling entity is boosted 592 * pi_se points to the donor, otherwise points to the dl_se it belongs 593 * to (the original one/itself). 594 */ 595 struct sched_dl_entity *pi_se; 596 #endif 597 }; 598 599 #ifdef CONFIG_UCLAMP_TASK 600 /* Number of utilization clamp buckets (shorter alias) */ 601 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT 602 603 /* 604 * Utilization clamp for a scheduling entity 605 * @value: clamp value "assigned" to a se 606 * @bucket_id: bucket index corresponding to the "assigned" value 607 * @active: the se is currently refcounted in a rq's bucket 608 * @user_defined: the requested clamp value comes from user-space 609 * 610 * The bucket_id is the index of the clamp bucket matching the clamp value 611 * which is pre-computed and stored to avoid expensive integer divisions from 612 * the fast path. 613 * 614 * The active bit is set whenever a task has got an "effective" value assigned, 615 * which can be different from the clamp value "requested" from user-space. 616 * This allows to know a task is refcounted in the rq's bucket corresponding 617 * to the "effective" bucket_id. 618 * 619 * The user_defined bit is set whenever a task has got a task-specific clamp 620 * value requested from userspace, i.e. the system defaults apply to this task 621 * just as a restriction. This allows to relax default clamps when a less 622 * restrictive task-specific value has been requested, thus allowing to 623 * implement a "nice" semantic. For example, a task running with a 20% 624 * default boost can still drop its own boosting to 0%. 625 */ 626 struct uclamp_se { 627 unsigned int value : bits_per(SCHED_CAPACITY_SCALE); 628 unsigned int bucket_id : bits_per(UCLAMP_BUCKETS); 629 unsigned int active : 1; 630 unsigned int user_defined : 1; 631 }; 632 #endif /* CONFIG_UCLAMP_TASK */ 633 634 union rcu_special { 635 struct { 636 u8 blocked; 637 u8 need_qs; 638 u8 exp_hint; /* Hint for performance. */ 639 u8 need_mb; /* Readers need smp_mb(). */ 640 } b; /* Bits. */ 641 u32 s; /* Set of bits. */ 642 }; 643 644 enum perf_event_task_context { 645 perf_invalid_context = -1, 646 perf_hw_context = 0, 647 perf_sw_context, 648 perf_nr_task_contexts, 649 }; 650 651 struct wake_q_node { 652 struct wake_q_node *next; 653 }; 654 655 struct kmap_ctrl { 656 #ifdef CONFIG_KMAP_LOCAL 657 int idx; 658 pte_t pteval[KM_MAX_IDX]; 659 #endif 660 }; 661 662 struct task_struct { 663 #ifdef CONFIG_THREAD_INFO_IN_TASK 664 /* 665 * For reasons of header soup (see current_thread_info()), this 666 * must be the first element of task_struct. 667 */ 668 struct thread_info thread_info; 669 #endif 670 unsigned int __state; 671 672 /* 673 * This begins the randomizable portion of task_struct. Only 674 * scheduling-critical items should be added above here. 675 */ 676 randomized_struct_fields_start 677 678 void *stack; 679 refcount_t usage; 680 /* Per task flags (PF_*), defined further below: */ 681 unsigned int flags; 682 unsigned int ptrace; 683 684 #ifdef CONFIG_SMP 685 int on_cpu; 686 struct __call_single_node wake_entry; 687 #ifdef CONFIG_THREAD_INFO_IN_TASK 688 /* Current CPU: */ 689 unsigned int cpu; 690 #endif 691 unsigned int wakee_flips; 692 unsigned long wakee_flip_decay_ts; 693 struct task_struct *last_wakee; 694 695 /* 696 * recent_used_cpu is initially set as the last CPU used by a task 697 * that wakes affine another task. Waker/wakee relationships can 698 * push tasks around a CPU where each wakeup moves to the next one. 699 * Tracking a recently used CPU allows a quick search for a recently 700 * used CPU that may be idle. 701 */ 702 int recent_used_cpu; 703 int wake_cpu; 704 #endif 705 int on_rq; 706 707 int prio; 708 int static_prio; 709 int normal_prio; 710 unsigned int rt_priority; 711 712 const struct sched_class *sched_class; 713 struct sched_entity se; 714 struct sched_rt_entity rt; 715 struct sched_dl_entity dl; 716 717 #ifdef CONFIG_SCHED_CORE 718 struct rb_node core_node; 719 unsigned long core_cookie; 720 unsigned int core_occupation; 721 #endif 722 723 #ifdef CONFIG_CGROUP_SCHED 724 struct task_group *sched_task_group; 725 #endif 726 727 #ifdef CONFIG_UCLAMP_TASK 728 /* 729 * Clamp values requested for a scheduling entity. 730 * Must be updated with task_rq_lock() held. 731 */ 732 struct uclamp_se uclamp_req[UCLAMP_CNT]; 733 /* 734 * Effective clamp values used for a scheduling entity. 735 * Must be updated with task_rq_lock() held. 736 */ 737 struct uclamp_se uclamp[UCLAMP_CNT]; 738 #endif 739 740 #ifdef CONFIG_PREEMPT_NOTIFIERS 741 /* List of struct preempt_notifier: */ 742 struct hlist_head preempt_notifiers; 743 #endif 744 745 #ifdef CONFIG_BLK_DEV_IO_TRACE 746 unsigned int btrace_seq; 747 #endif 748 749 unsigned int policy; 750 int nr_cpus_allowed; 751 const cpumask_t *cpus_ptr; 752 cpumask_t cpus_mask; 753 void *migration_pending; 754 #ifdef CONFIG_SMP 755 unsigned short migration_disabled; 756 #endif 757 unsigned short migration_flags; 758 759 #ifdef CONFIG_PREEMPT_RCU 760 int rcu_read_lock_nesting; 761 union rcu_special rcu_read_unlock_special; 762 struct list_head rcu_node_entry; 763 struct rcu_node *rcu_blocked_node; 764 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 765 766 #ifdef CONFIG_TASKS_RCU 767 unsigned long rcu_tasks_nvcsw; 768 u8 rcu_tasks_holdout; 769 u8 rcu_tasks_idx; 770 int rcu_tasks_idle_cpu; 771 struct list_head rcu_tasks_holdout_list; 772 #endif /* #ifdef CONFIG_TASKS_RCU */ 773 774 #ifdef CONFIG_TASKS_TRACE_RCU 775 int trc_reader_nesting; 776 int trc_ipi_to_cpu; 777 union rcu_special trc_reader_special; 778 bool trc_reader_checked; 779 struct list_head trc_holdout_list; 780 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */ 781 782 struct sched_info sched_info; 783 784 struct list_head tasks; 785 #ifdef CONFIG_SMP 786 struct plist_node pushable_tasks; 787 struct rb_node pushable_dl_tasks; 788 #endif 789 790 struct mm_struct *mm; 791 struct mm_struct *active_mm; 792 793 /* Per-thread vma caching: */ 794 struct vmacache vmacache; 795 796 #ifdef SPLIT_RSS_COUNTING 797 struct task_rss_stat rss_stat; 798 #endif 799 int exit_state; 800 int exit_code; 801 int exit_signal; 802 /* The signal sent when the parent dies: */ 803 int pdeath_signal; 804 /* JOBCTL_*, siglock protected: */ 805 unsigned long jobctl; 806 807 /* Used for emulating ABI behavior of previous Linux versions: */ 808 unsigned int personality; 809 810 /* Scheduler bits, serialized by scheduler locks: */ 811 unsigned sched_reset_on_fork:1; 812 unsigned sched_contributes_to_load:1; 813 unsigned sched_migrated:1; 814 #ifdef CONFIG_PSI 815 unsigned sched_psi_wake_requeue:1; 816 #endif 817 818 /* Force alignment to the next boundary: */ 819 unsigned :0; 820 821 /* Unserialized, strictly 'current' */ 822 823 /* 824 * This field must not be in the scheduler word above due to wakelist 825 * queueing no longer being serialized by p->on_cpu. However: 826 * 827 * p->XXX = X; ttwu() 828 * schedule() if (p->on_rq && ..) // false 829 * smp_mb__after_spinlock(); if (smp_load_acquire(&p->on_cpu) && //true 830 * deactivate_task() ttwu_queue_wakelist()) 831 * p->on_rq = 0; p->sched_remote_wakeup = Y; 832 * 833 * guarantees all stores of 'current' are visible before 834 * ->sched_remote_wakeup gets used, so it can be in this word. 835 */ 836 unsigned sched_remote_wakeup:1; 837 838 /* Bit to tell LSMs we're in execve(): */ 839 unsigned in_execve:1; 840 unsigned in_iowait:1; 841 #ifndef TIF_RESTORE_SIGMASK 842 unsigned restore_sigmask:1; 843 #endif 844 #ifdef CONFIG_MEMCG 845 unsigned in_user_fault:1; 846 #endif 847 #ifdef CONFIG_COMPAT_BRK 848 unsigned brk_randomized:1; 849 #endif 850 #ifdef CONFIG_CGROUPS 851 /* disallow userland-initiated cgroup migration */ 852 unsigned no_cgroup_migration:1; 853 /* task is frozen/stopped (used by the cgroup freezer) */ 854 unsigned frozen:1; 855 #endif 856 #ifdef CONFIG_BLK_CGROUP 857 unsigned use_memdelay:1; 858 #endif 859 #ifdef CONFIG_PSI 860 /* Stalled due to lack of memory */ 861 unsigned in_memstall:1; 862 #endif 863 #ifdef CONFIG_PAGE_OWNER 864 /* Used by page_owner=on to detect recursion in page tracking. */ 865 unsigned in_page_owner:1; 866 #endif 867 868 unsigned long atomic_flags; /* Flags requiring atomic access. */ 869 870 struct restart_block restart_block; 871 872 pid_t pid; 873 pid_t tgid; 874 875 #ifdef CONFIG_STACKPROTECTOR 876 /* Canary value for the -fstack-protector GCC feature: */ 877 unsigned long stack_canary; 878 #endif 879 /* 880 * Pointers to the (original) parent process, youngest child, younger sibling, 881 * older sibling, respectively. (p->father can be replaced with 882 * p->real_parent->pid) 883 */ 884 885 /* Real parent process: */ 886 struct task_struct __rcu *real_parent; 887 888 /* Recipient of SIGCHLD, wait4() reports: */ 889 struct task_struct __rcu *parent; 890 891 /* 892 * Children/sibling form the list of natural children: 893 */ 894 struct list_head children; 895 struct list_head sibling; 896 struct task_struct *group_leader; 897 898 /* 899 * 'ptraced' is the list of tasks this task is using ptrace() on. 900 * 901 * This includes both natural children and PTRACE_ATTACH targets. 902 * 'ptrace_entry' is this task's link on the p->parent->ptraced list. 903 */ 904 struct list_head ptraced; 905 struct list_head ptrace_entry; 906 907 /* PID/PID hash table linkage. */ 908 struct pid *thread_pid; 909 struct hlist_node pid_links[PIDTYPE_MAX]; 910 struct list_head thread_group; 911 struct list_head thread_node; 912 913 struct completion *vfork_done; 914 915 /* CLONE_CHILD_SETTID: */ 916 int __user *set_child_tid; 917 918 /* CLONE_CHILD_CLEARTID: */ 919 int __user *clear_child_tid; 920 921 /* PF_IO_WORKER */ 922 void *pf_io_worker; 923 924 u64 utime; 925 u64 stime; 926 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME 927 u64 utimescaled; 928 u64 stimescaled; 929 #endif 930 u64 gtime; 931 struct prev_cputime prev_cputime; 932 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 933 struct vtime vtime; 934 #endif 935 936 #ifdef CONFIG_NO_HZ_FULL 937 atomic_t tick_dep_mask; 938 #endif 939 /* Context switch counts: */ 940 unsigned long nvcsw; 941 unsigned long nivcsw; 942 943 /* Monotonic time in nsecs: */ 944 u64 start_time; 945 946 /* Boot based time in nsecs: */ 947 u64 start_boottime; 948 949 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */ 950 unsigned long min_flt; 951 unsigned long maj_flt; 952 953 /* Empty if CONFIG_POSIX_CPUTIMERS=n */ 954 struct posix_cputimers posix_cputimers; 955 956 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK 957 struct posix_cputimers_work posix_cputimers_work; 958 #endif 959 960 /* Process credentials: */ 961 962 /* Tracer's credentials at attach: */ 963 const struct cred __rcu *ptracer_cred; 964 965 /* Objective and real subjective task credentials (COW): */ 966 const struct cred __rcu *real_cred; 967 968 /* Effective (overridable) subjective task credentials (COW): */ 969 const struct cred __rcu *cred; 970 971 #ifdef CONFIG_KEYS 972 /* Cached requested key. */ 973 struct key *cached_requested_key; 974 #endif 975 976 /* 977 * executable name, excluding path. 978 * 979 * - normally initialized setup_new_exec() 980 * - access it with [gs]et_task_comm() 981 * - lock it with task_lock() 982 */ 983 char comm[TASK_COMM_LEN]; 984 985 struct nameidata *nameidata; 986 987 #ifdef CONFIG_SYSVIPC 988 struct sysv_sem sysvsem; 989 struct sysv_shm sysvshm; 990 #endif 991 #ifdef CONFIG_DETECT_HUNG_TASK 992 unsigned long last_switch_count; 993 unsigned long last_switch_time; 994 #endif 995 /* Filesystem information: */ 996 struct fs_struct *fs; 997 998 /* Open file information: */ 999 struct files_struct *files; 1000 1001 #ifdef CONFIG_IO_URING 1002 struct io_uring_task *io_uring; 1003 #endif 1004 1005 /* Namespaces: */ 1006 struct nsproxy *nsproxy; 1007 1008 /* Signal handlers: */ 1009 struct signal_struct *signal; 1010 struct sighand_struct __rcu *sighand; 1011 sigset_t blocked; 1012 sigset_t real_blocked; 1013 /* Restored if set_restore_sigmask() was used: */ 1014 sigset_t saved_sigmask; 1015 struct sigpending pending; 1016 unsigned long sas_ss_sp; 1017 size_t sas_ss_size; 1018 unsigned int sas_ss_flags; 1019 1020 struct callback_head *task_works; 1021 1022 #ifdef CONFIG_AUDIT 1023 #ifdef CONFIG_AUDITSYSCALL 1024 struct audit_context *audit_context; 1025 #endif 1026 kuid_t loginuid; 1027 unsigned int sessionid; 1028 #endif 1029 struct seccomp seccomp; 1030 struct syscall_user_dispatch syscall_dispatch; 1031 1032 /* Thread group tracking: */ 1033 u64 parent_exec_id; 1034 u64 self_exec_id; 1035 1036 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */ 1037 spinlock_t alloc_lock; 1038 1039 /* Protection of the PI data structures: */ 1040 raw_spinlock_t pi_lock; 1041 1042 struct wake_q_node wake_q; 1043 1044 #ifdef CONFIG_RT_MUTEXES 1045 /* PI waiters blocked on a rt_mutex held by this task: */ 1046 struct rb_root_cached pi_waiters; 1047 /* Updated under owner's pi_lock and rq lock */ 1048 struct task_struct *pi_top_task; 1049 /* Deadlock detection and priority inheritance handling: */ 1050 struct rt_mutex_waiter *pi_blocked_on; 1051 #endif 1052 1053 #ifdef CONFIG_DEBUG_MUTEXES 1054 /* Mutex deadlock detection: */ 1055 struct mutex_waiter *blocked_on; 1056 #endif 1057 1058 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1059 int non_block_count; 1060 #endif 1061 1062 #ifdef CONFIG_TRACE_IRQFLAGS 1063 struct irqtrace_events irqtrace; 1064 unsigned int hardirq_threaded; 1065 u64 hardirq_chain_key; 1066 int softirqs_enabled; 1067 int softirq_context; 1068 int irq_config; 1069 #endif 1070 #ifdef CONFIG_PREEMPT_RT 1071 int softirq_disable_cnt; 1072 #endif 1073 1074 #ifdef CONFIG_LOCKDEP 1075 # define MAX_LOCK_DEPTH 48UL 1076 u64 curr_chain_key; 1077 int lockdep_depth; 1078 unsigned int lockdep_recursion; 1079 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1080 #endif 1081 1082 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP) 1083 unsigned int in_ubsan; 1084 #endif 1085 1086 /* Journalling filesystem info: */ 1087 void *journal_info; 1088 1089 /* Stacked block device info: */ 1090 struct bio_list *bio_list; 1091 1092 #ifdef CONFIG_BLOCK 1093 /* Stack plugging: */ 1094 struct blk_plug *plug; 1095 #endif 1096 1097 /* VM state: */ 1098 struct reclaim_state *reclaim_state; 1099 1100 struct backing_dev_info *backing_dev_info; 1101 1102 struct io_context *io_context; 1103 1104 #ifdef CONFIG_COMPACTION 1105 struct capture_control *capture_control; 1106 #endif 1107 /* Ptrace state: */ 1108 unsigned long ptrace_message; 1109 kernel_siginfo_t *last_siginfo; 1110 1111 struct task_io_accounting ioac; 1112 #ifdef CONFIG_PSI 1113 /* Pressure stall state */ 1114 unsigned int psi_flags; 1115 #endif 1116 #ifdef CONFIG_TASK_XACCT 1117 /* Accumulated RSS usage: */ 1118 u64 acct_rss_mem1; 1119 /* Accumulated virtual memory usage: */ 1120 u64 acct_vm_mem1; 1121 /* stime + utime since last update: */ 1122 u64 acct_timexpd; 1123 #endif 1124 #ifdef CONFIG_CPUSETS 1125 /* Protected by ->alloc_lock: */ 1126 nodemask_t mems_allowed; 1127 /* Sequence number to catch updates: */ 1128 seqcount_spinlock_t mems_allowed_seq; 1129 int cpuset_mem_spread_rotor; 1130 int cpuset_slab_spread_rotor; 1131 #endif 1132 #ifdef CONFIG_CGROUPS 1133 /* Control Group info protected by css_set_lock: */ 1134 struct css_set __rcu *cgroups; 1135 /* cg_list protected by css_set_lock and tsk->alloc_lock: */ 1136 struct list_head cg_list; 1137 #endif 1138 #ifdef CONFIG_X86_CPU_RESCTRL 1139 u32 closid; 1140 u32 rmid; 1141 #endif 1142 #ifdef CONFIG_FUTEX 1143 struct robust_list_head __user *robust_list; 1144 #ifdef CONFIG_COMPAT 1145 struct compat_robust_list_head __user *compat_robust_list; 1146 #endif 1147 struct list_head pi_state_list; 1148 struct futex_pi_state *pi_state_cache; 1149 struct mutex futex_exit_mutex; 1150 unsigned int futex_state; 1151 #endif 1152 #ifdef CONFIG_PERF_EVENTS 1153 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts]; 1154 struct mutex perf_event_mutex; 1155 struct list_head perf_event_list; 1156 #endif 1157 #ifdef CONFIG_DEBUG_PREEMPT 1158 unsigned long preempt_disable_ip; 1159 #endif 1160 #ifdef CONFIG_NUMA 1161 /* Protected by alloc_lock: */ 1162 struct mempolicy *mempolicy; 1163 short il_prev; 1164 short pref_node_fork; 1165 #endif 1166 #ifdef CONFIG_NUMA_BALANCING 1167 int numa_scan_seq; 1168 unsigned int numa_scan_period; 1169 unsigned int numa_scan_period_max; 1170 int numa_preferred_nid; 1171 unsigned long numa_migrate_retry; 1172 /* Migration stamp: */ 1173 u64 node_stamp; 1174 u64 last_task_numa_placement; 1175 u64 last_sum_exec_runtime; 1176 struct callback_head numa_work; 1177 1178 /* 1179 * This pointer is only modified for current in syscall and 1180 * pagefault context (and for tasks being destroyed), so it can be read 1181 * from any of the following contexts: 1182 * - RCU read-side critical section 1183 * - current->numa_group from everywhere 1184 * - task's runqueue locked, task not running 1185 */ 1186 struct numa_group __rcu *numa_group; 1187 1188 /* 1189 * numa_faults is an array split into four regions: 1190 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer 1191 * in this precise order. 1192 * 1193 * faults_memory: Exponential decaying average of faults on a per-node 1194 * basis. Scheduling placement decisions are made based on these 1195 * counts. The values remain static for the duration of a PTE scan. 1196 * faults_cpu: Track the nodes the process was running on when a NUMA 1197 * hinting fault was incurred. 1198 * faults_memory_buffer and faults_cpu_buffer: Record faults per node 1199 * during the current scan window. When the scan completes, the counts 1200 * in faults_memory and faults_cpu decay and these values are copied. 1201 */ 1202 unsigned long *numa_faults; 1203 unsigned long total_numa_faults; 1204 1205 /* 1206 * numa_faults_locality tracks if faults recorded during the last 1207 * scan window were remote/local or failed to migrate. The task scan 1208 * period is adapted based on the locality of the faults with different 1209 * weights depending on whether they were shared or private faults 1210 */ 1211 unsigned long numa_faults_locality[3]; 1212 1213 unsigned long numa_pages_migrated; 1214 #endif /* CONFIG_NUMA_BALANCING */ 1215 1216 #ifdef CONFIG_RSEQ 1217 struct rseq __user *rseq; 1218 u32 rseq_sig; 1219 /* 1220 * RmW on rseq_event_mask must be performed atomically 1221 * with respect to preemption. 1222 */ 1223 unsigned long rseq_event_mask; 1224 #endif 1225 1226 struct tlbflush_unmap_batch tlb_ubc; 1227 1228 union { 1229 refcount_t rcu_users; 1230 struct rcu_head rcu; 1231 }; 1232 1233 /* Cache last used pipe for splice(): */ 1234 struct pipe_inode_info *splice_pipe; 1235 1236 struct page_frag task_frag; 1237 1238 #ifdef CONFIG_TASK_DELAY_ACCT 1239 struct task_delay_info *delays; 1240 #endif 1241 1242 #ifdef CONFIG_FAULT_INJECTION 1243 int make_it_fail; 1244 unsigned int fail_nth; 1245 #endif 1246 /* 1247 * When (nr_dirtied >= nr_dirtied_pause), it's time to call 1248 * balance_dirty_pages() for a dirty throttling pause: 1249 */ 1250 int nr_dirtied; 1251 int nr_dirtied_pause; 1252 /* Start of a write-and-pause period: */ 1253 unsigned long dirty_paused_when; 1254 1255 #ifdef CONFIG_LATENCYTOP 1256 int latency_record_count; 1257 struct latency_record latency_record[LT_SAVECOUNT]; 1258 #endif 1259 /* 1260 * Time slack values; these are used to round up poll() and 1261 * select() etc timeout values. These are in nanoseconds. 1262 */ 1263 u64 timer_slack_ns; 1264 u64 default_timer_slack_ns; 1265 1266 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) 1267 unsigned int kasan_depth; 1268 #endif 1269 1270 #ifdef CONFIG_KCSAN 1271 struct kcsan_ctx kcsan_ctx; 1272 #ifdef CONFIG_TRACE_IRQFLAGS 1273 struct irqtrace_events kcsan_save_irqtrace; 1274 #endif 1275 #endif 1276 1277 #if IS_ENABLED(CONFIG_KUNIT) 1278 struct kunit *kunit_test; 1279 #endif 1280 1281 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1282 /* Index of current stored address in ret_stack: */ 1283 int curr_ret_stack; 1284 int curr_ret_depth; 1285 1286 /* Stack of return addresses for return function tracing: */ 1287 struct ftrace_ret_stack *ret_stack; 1288 1289 /* Timestamp for last schedule: */ 1290 unsigned long long ftrace_timestamp; 1291 1292 /* 1293 * Number of functions that haven't been traced 1294 * because of depth overrun: 1295 */ 1296 atomic_t trace_overrun; 1297 1298 /* Pause tracing: */ 1299 atomic_t tracing_graph_pause; 1300 #endif 1301 1302 #ifdef CONFIG_TRACING 1303 /* State flags for use by tracers: */ 1304 unsigned long trace; 1305 1306 /* Bitmask and counter of trace recursion: */ 1307 unsigned long trace_recursion; 1308 #endif /* CONFIG_TRACING */ 1309 1310 #ifdef CONFIG_KCOV 1311 /* See kernel/kcov.c for more details. */ 1312 1313 /* Coverage collection mode enabled for this task (0 if disabled): */ 1314 unsigned int kcov_mode; 1315 1316 /* Size of the kcov_area: */ 1317 unsigned int kcov_size; 1318 1319 /* Buffer for coverage collection: */ 1320 void *kcov_area; 1321 1322 /* KCOV descriptor wired with this task or NULL: */ 1323 struct kcov *kcov; 1324 1325 /* KCOV common handle for remote coverage collection: */ 1326 u64 kcov_handle; 1327 1328 /* KCOV sequence number: */ 1329 int kcov_sequence; 1330 1331 /* Collect coverage from softirq context: */ 1332 unsigned int kcov_softirq; 1333 #endif 1334 1335 #ifdef CONFIG_MEMCG 1336 struct mem_cgroup *memcg_in_oom; 1337 gfp_t memcg_oom_gfp_mask; 1338 int memcg_oom_order; 1339 1340 /* Number of pages to reclaim on returning to userland: */ 1341 unsigned int memcg_nr_pages_over_high; 1342 1343 /* Used by memcontrol for targeted memcg charge: */ 1344 struct mem_cgroup *active_memcg; 1345 #endif 1346 1347 #ifdef CONFIG_BLK_CGROUP 1348 struct request_queue *throttle_queue; 1349 #endif 1350 1351 #ifdef CONFIG_UPROBES 1352 struct uprobe_task *utask; 1353 #endif 1354 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1355 unsigned int sequential_io; 1356 unsigned int sequential_io_avg; 1357 #endif 1358 struct kmap_ctrl kmap_ctrl; 1359 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1360 unsigned long task_state_change; 1361 #endif 1362 int pagefault_disabled; 1363 #ifdef CONFIG_MMU 1364 struct task_struct *oom_reaper_list; 1365 #endif 1366 #ifdef CONFIG_VMAP_STACK 1367 struct vm_struct *stack_vm_area; 1368 #endif 1369 #ifdef CONFIG_THREAD_INFO_IN_TASK 1370 /* A live task holds one reference: */ 1371 refcount_t stack_refcount; 1372 #endif 1373 #ifdef CONFIG_LIVEPATCH 1374 int patch_state; 1375 #endif 1376 #ifdef CONFIG_SECURITY 1377 /* Used by LSM modules for access restriction: */ 1378 void *security; 1379 #endif 1380 #ifdef CONFIG_BPF_SYSCALL 1381 /* Used by BPF task local storage */ 1382 struct bpf_local_storage __rcu *bpf_storage; 1383 /* Used for BPF run context */ 1384 struct bpf_run_ctx *bpf_ctx; 1385 #endif 1386 1387 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK 1388 unsigned long lowest_stack; 1389 unsigned long prev_lowest_stack; 1390 #endif 1391 1392 #ifdef CONFIG_X86_MCE 1393 void __user *mce_vaddr; 1394 __u64 mce_kflags; 1395 u64 mce_addr; 1396 __u64 mce_ripv : 1, 1397 mce_whole_page : 1, 1398 __mce_reserved : 62; 1399 struct callback_head mce_kill_me; 1400 #endif 1401 1402 #ifdef CONFIG_KRETPROBES 1403 struct llist_head kretprobe_instances; 1404 #endif 1405 1406 /* 1407 * New fields for task_struct should be added above here, so that 1408 * they are included in the randomized portion of task_struct. 1409 */ 1410 randomized_struct_fields_end 1411 1412 /* CPU-specific state of this task: */ 1413 struct thread_struct thread; 1414 1415 /* 1416 * WARNING: on x86, 'thread_struct' contains a variable-sized 1417 * structure. It *MUST* be at the end of 'task_struct'. 1418 * 1419 * Do not put anything below here! 1420 */ 1421 }; 1422 1423 static inline struct pid *task_pid(struct task_struct *task) 1424 { 1425 return task->thread_pid; 1426 } 1427 1428 /* 1429 * the helpers to get the task's different pids as they are seen 1430 * from various namespaces 1431 * 1432 * task_xid_nr() : global id, i.e. the id seen from the init namespace; 1433 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of 1434 * current. 1435 * task_xid_nr_ns() : id seen from the ns specified; 1436 * 1437 * see also pid_nr() etc in include/linux/pid.h 1438 */ 1439 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, struct pid_namespace *ns); 1440 1441 static inline pid_t task_pid_nr(struct task_struct *tsk) 1442 { 1443 return tsk->pid; 1444 } 1445 1446 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) 1447 { 1448 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns); 1449 } 1450 1451 static inline pid_t task_pid_vnr(struct task_struct *tsk) 1452 { 1453 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL); 1454 } 1455 1456 1457 static inline pid_t task_tgid_nr(struct task_struct *tsk) 1458 { 1459 return tsk->tgid; 1460 } 1461 1462 /** 1463 * pid_alive - check that a task structure is not stale 1464 * @p: Task structure to be checked. 1465 * 1466 * Test if a process is not yet dead (at most zombie state) 1467 * If pid_alive fails, then pointers within the task structure 1468 * can be stale and must not be dereferenced. 1469 * 1470 * Return: 1 if the process is alive. 0 otherwise. 1471 */ 1472 static inline int pid_alive(const struct task_struct *p) 1473 { 1474 return p->thread_pid != NULL; 1475 } 1476 1477 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) 1478 { 1479 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns); 1480 } 1481 1482 static inline pid_t task_pgrp_vnr(struct task_struct *tsk) 1483 { 1484 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL); 1485 } 1486 1487 1488 static inline pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) 1489 { 1490 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns); 1491 } 1492 1493 static inline pid_t task_session_vnr(struct task_struct *tsk) 1494 { 1495 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); 1496 } 1497 1498 static inline pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) 1499 { 1500 return __task_pid_nr_ns(tsk, PIDTYPE_TGID, ns); 1501 } 1502 1503 static inline pid_t task_tgid_vnr(struct task_struct *tsk) 1504 { 1505 return __task_pid_nr_ns(tsk, PIDTYPE_TGID, NULL); 1506 } 1507 1508 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns) 1509 { 1510 pid_t pid = 0; 1511 1512 rcu_read_lock(); 1513 if (pid_alive(tsk)) 1514 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns); 1515 rcu_read_unlock(); 1516 1517 return pid; 1518 } 1519 1520 static inline pid_t task_ppid_nr(const struct task_struct *tsk) 1521 { 1522 return task_ppid_nr_ns(tsk, &init_pid_ns); 1523 } 1524 1525 /* Obsolete, do not use: */ 1526 static inline pid_t task_pgrp_nr(struct task_struct *tsk) 1527 { 1528 return task_pgrp_nr_ns(tsk, &init_pid_ns); 1529 } 1530 1531 #define TASK_REPORT_IDLE (TASK_REPORT + 1) 1532 #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1) 1533 1534 static inline unsigned int task_state_index(struct task_struct *tsk) 1535 { 1536 unsigned int tsk_state = READ_ONCE(tsk->__state); 1537 unsigned int state = (tsk_state | tsk->exit_state) & TASK_REPORT; 1538 1539 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX); 1540 1541 if (tsk_state == TASK_IDLE) 1542 state = TASK_REPORT_IDLE; 1543 1544 return fls(state); 1545 } 1546 1547 static inline char task_index_to_char(unsigned int state) 1548 { 1549 static const char state_char[] = "RSDTtXZPI"; 1550 1551 BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1); 1552 1553 return state_char[state]; 1554 } 1555 1556 static inline char task_state_to_char(struct task_struct *tsk) 1557 { 1558 return task_index_to_char(task_state_index(tsk)); 1559 } 1560 1561 /** 1562 * is_global_init - check if a task structure is init. Since init 1563 * is free to have sub-threads we need to check tgid. 1564 * @tsk: Task structure to be checked. 1565 * 1566 * Check if a task structure is the first user space task the kernel created. 1567 * 1568 * Return: 1 if the task structure is init. 0 otherwise. 1569 */ 1570 static inline int is_global_init(struct task_struct *tsk) 1571 { 1572 return task_tgid_nr(tsk) == 1; 1573 } 1574 1575 extern struct pid *cad_pid; 1576 1577 /* 1578 * Per process flags 1579 */ 1580 #define PF_VCPU 0x00000001 /* I'm a virtual CPU */ 1581 #define PF_IDLE 0x00000002 /* I am an IDLE thread */ 1582 #define PF_EXITING 0x00000004 /* Getting shut down */ 1583 #define PF_IO_WORKER 0x00000010 /* Task is an IO worker */ 1584 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 1585 #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */ 1586 #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */ 1587 #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */ 1588 #define PF_DUMPCORE 0x00000200 /* Dumped core */ 1589 #define PF_SIGNALED 0x00000400 /* Killed by a signal */ 1590 #define PF_MEMALLOC 0x00000800 /* Allocating memory */ 1591 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */ 1592 #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */ 1593 #define PF_USED_ASYNC 0x00004000 /* Used async_schedule*(), used by module init */ 1594 #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */ 1595 #define PF_FROZEN 0x00010000 /* Frozen for system suspend */ 1596 #define PF_KSWAPD 0x00020000 /* I am kswapd */ 1597 #define PF_MEMALLOC_NOFS 0x00040000 /* All allocation requests will inherit GFP_NOFS */ 1598 #define PF_MEMALLOC_NOIO 0x00080000 /* All allocation requests will inherit GFP_NOIO */ 1599 #define PF_LOCAL_THROTTLE 0x00100000 /* Throttle writes only against the bdi I write to, 1600 * I am cleaning dirty pages from some other bdi. */ 1601 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 1602 #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */ 1603 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ 1604 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */ 1605 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 1606 #define PF_MEMALLOC_PIN 0x10000000 /* Allocation context constrained to zones which allow long term pinning. */ 1607 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ 1608 #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */ 1609 1610 /* 1611 * Only the _current_ task can read/write to tsk->flags, but other 1612 * tasks can access tsk->flags in readonly mode for example 1613 * with tsk_used_math (like during threaded core dumping). 1614 * There is however an exception to this rule during ptrace 1615 * or during fork: the ptracer task is allowed to write to the 1616 * child->flags of its traced child (same goes for fork, the parent 1617 * can write to the child->flags), because we're guaranteed the 1618 * child is not running and in turn not changing child->flags 1619 * at the same time the parent does it. 1620 */ 1621 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1622 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1623 #define clear_used_math() clear_stopped_child_used_math(current) 1624 #define set_used_math() set_stopped_child_used_math(current) 1625 1626 #define conditional_stopped_child_used_math(condition, child) \ 1627 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1628 1629 #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current) 1630 1631 #define copy_to_stopped_child_used_math(child) \ 1632 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1633 1634 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1635 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1636 #define used_math() tsk_used_math(current) 1637 1638 static inline bool is_percpu_thread(void) 1639 { 1640 #ifdef CONFIG_SMP 1641 return (current->flags & PF_NO_SETAFFINITY) && 1642 (current->nr_cpus_allowed == 1); 1643 #else 1644 return true; 1645 #endif 1646 } 1647 1648 /* Per-process atomic flags. */ 1649 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */ 1650 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */ 1651 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */ 1652 #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */ 1653 #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/ 1654 #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */ 1655 #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */ 1656 #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */ 1657 1658 #define TASK_PFA_TEST(name, func) \ 1659 static inline bool task_##func(struct task_struct *p) \ 1660 { return test_bit(PFA_##name, &p->atomic_flags); } 1661 1662 #define TASK_PFA_SET(name, func) \ 1663 static inline void task_set_##func(struct task_struct *p) \ 1664 { set_bit(PFA_##name, &p->atomic_flags); } 1665 1666 #define TASK_PFA_CLEAR(name, func) \ 1667 static inline void task_clear_##func(struct task_struct *p) \ 1668 { clear_bit(PFA_##name, &p->atomic_flags); } 1669 1670 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs) 1671 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs) 1672 1673 TASK_PFA_TEST(SPREAD_PAGE, spread_page) 1674 TASK_PFA_SET(SPREAD_PAGE, spread_page) 1675 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page) 1676 1677 TASK_PFA_TEST(SPREAD_SLAB, spread_slab) 1678 TASK_PFA_SET(SPREAD_SLAB, spread_slab) 1679 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab) 1680 1681 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable) 1682 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable) 1683 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable) 1684 1685 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1686 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1687 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1688 1689 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1690 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1691 1692 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable) 1693 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable) 1694 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable) 1695 1696 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1697 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1698 1699 static inline void 1700 current_restore_flags(unsigned long orig_flags, unsigned long flags) 1701 { 1702 current->flags &= ~flags; 1703 current->flags |= orig_flags & flags; 1704 } 1705 1706 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 1707 extern int task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed); 1708 #ifdef CONFIG_SMP 1709 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask); 1710 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask); 1711 #else 1712 static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) 1713 { 1714 } 1715 static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask) 1716 { 1717 if (!cpumask_test_cpu(0, new_mask)) 1718 return -EINVAL; 1719 return 0; 1720 } 1721 #endif 1722 1723 extern int yield_to(struct task_struct *p, bool preempt); 1724 extern void set_user_nice(struct task_struct *p, long nice); 1725 extern int task_prio(const struct task_struct *p); 1726 1727 /** 1728 * task_nice - return the nice value of a given task. 1729 * @p: the task in question. 1730 * 1731 * Return: The nice value [ -20 ... 0 ... 19 ]. 1732 */ 1733 static inline int task_nice(const struct task_struct *p) 1734 { 1735 return PRIO_TO_NICE((p)->static_prio); 1736 } 1737 1738 extern int can_nice(const struct task_struct *p, const int nice); 1739 extern int task_curr(const struct task_struct *p); 1740 extern int idle_cpu(int cpu); 1741 extern int available_idle_cpu(int cpu); 1742 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *); 1743 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *); 1744 extern void sched_set_fifo(struct task_struct *p); 1745 extern void sched_set_fifo_low(struct task_struct *p); 1746 extern void sched_set_normal(struct task_struct *p, int nice); 1747 extern int sched_setattr(struct task_struct *, const struct sched_attr *); 1748 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *); 1749 extern struct task_struct *idle_task(int cpu); 1750 1751 /** 1752 * is_idle_task - is the specified task an idle task? 1753 * @p: the task in question. 1754 * 1755 * Return: 1 if @p is an idle task. 0 otherwise. 1756 */ 1757 static __always_inline bool is_idle_task(const struct task_struct *p) 1758 { 1759 return !!(p->flags & PF_IDLE); 1760 } 1761 1762 extern struct task_struct *curr_task(int cpu); 1763 extern void ia64_set_curr_task(int cpu, struct task_struct *p); 1764 1765 void yield(void); 1766 1767 union thread_union { 1768 #ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK 1769 struct task_struct task; 1770 #endif 1771 #ifndef CONFIG_THREAD_INFO_IN_TASK 1772 struct thread_info thread_info; 1773 #endif 1774 unsigned long stack[THREAD_SIZE/sizeof(long)]; 1775 }; 1776 1777 #ifndef CONFIG_THREAD_INFO_IN_TASK 1778 extern struct thread_info init_thread_info; 1779 #endif 1780 1781 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)]; 1782 1783 #ifdef CONFIG_THREAD_INFO_IN_TASK 1784 static inline struct thread_info *task_thread_info(struct task_struct *task) 1785 { 1786 return &task->thread_info; 1787 } 1788 #elif !defined(__HAVE_THREAD_FUNCTIONS) 1789 # define task_thread_info(task) ((struct thread_info *)(task)->stack) 1790 #endif 1791 1792 /* 1793 * find a task by one of its numerical ids 1794 * 1795 * find_task_by_pid_ns(): 1796 * finds a task by its pid in the specified namespace 1797 * find_task_by_vpid(): 1798 * finds a task by its virtual pid 1799 * 1800 * see also find_vpid() etc in include/linux/pid.h 1801 */ 1802 1803 extern struct task_struct *find_task_by_vpid(pid_t nr); 1804 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns); 1805 1806 /* 1807 * find a task by its virtual pid and get the task struct 1808 */ 1809 extern struct task_struct *find_get_task_by_vpid(pid_t nr); 1810 1811 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 1812 extern int wake_up_process(struct task_struct *tsk); 1813 extern void wake_up_new_task(struct task_struct *tsk); 1814 1815 #ifdef CONFIG_SMP 1816 extern void kick_process(struct task_struct *tsk); 1817 #else 1818 static inline void kick_process(struct task_struct *tsk) { } 1819 #endif 1820 1821 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); 1822 1823 static inline void set_task_comm(struct task_struct *tsk, const char *from) 1824 { 1825 __set_task_comm(tsk, from, false); 1826 } 1827 1828 extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk); 1829 #define get_task_comm(buf, tsk) ({ \ 1830 BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN); \ 1831 __get_task_comm(buf, sizeof(buf), tsk); \ 1832 }) 1833 1834 #ifdef CONFIG_SMP 1835 static __always_inline void scheduler_ipi(void) 1836 { 1837 /* 1838 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting 1839 * TIF_NEED_RESCHED remotely (for the first time) will also send 1840 * this IPI. 1841 */ 1842 preempt_fold_need_resched(); 1843 } 1844 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state); 1845 #else 1846 static inline void scheduler_ipi(void) { } 1847 static inline unsigned long wait_task_inactive(struct task_struct *p, unsigned int match_state) 1848 { 1849 return 1; 1850 } 1851 #endif 1852 1853 /* 1854 * Set thread flags in other task's structures. 1855 * See asm/thread_info.h for TIF_xxxx flags available: 1856 */ 1857 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 1858 { 1859 set_ti_thread_flag(task_thread_info(tsk), flag); 1860 } 1861 1862 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 1863 { 1864 clear_ti_thread_flag(task_thread_info(tsk), flag); 1865 } 1866 1867 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag, 1868 bool value) 1869 { 1870 update_ti_thread_flag(task_thread_info(tsk), flag, value); 1871 } 1872 1873 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 1874 { 1875 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 1876 } 1877 1878 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 1879 { 1880 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 1881 } 1882 1883 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 1884 { 1885 return test_ti_thread_flag(task_thread_info(tsk), flag); 1886 } 1887 1888 static inline void set_tsk_need_resched(struct task_struct *tsk) 1889 { 1890 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 1891 } 1892 1893 static inline void clear_tsk_need_resched(struct task_struct *tsk) 1894 { 1895 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 1896 } 1897 1898 static inline int test_tsk_need_resched(struct task_struct *tsk) 1899 { 1900 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 1901 } 1902 1903 /* 1904 * cond_resched() and cond_resched_lock(): latency reduction via 1905 * explicit rescheduling in places that are safe. The return 1906 * value indicates whether a reschedule was done in fact. 1907 * cond_resched_lock() will drop the spinlock before scheduling, 1908 */ 1909 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) 1910 extern int __cond_resched(void); 1911 1912 #ifdef CONFIG_PREEMPT_DYNAMIC 1913 1914 DECLARE_STATIC_CALL(cond_resched, __cond_resched); 1915 1916 static __always_inline int _cond_resched(void) 1917 { 1918 return static_call_mod(cond_resched)(); 1919 } 1920 1921 #else 1922 1923 static inline int _cond_resched(void) 1924 { 1925 return __cond_resched(); 1926 } 1927 1928 #endif /* CONFIG_PREEMPT_DYNAMIC */ 1929 1930 #else 1931 1932 static inline int _cond_resched(void) { return 0; } 1933 1934 #endif /* !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) */ 1935 1936 #define cond_resched() ({ \ 1937 ___might_sleep(__FILE__, __LINE__, 0); \ 1938 _cond_resched(); \ 1939 }) 1940 1941 extern int __cond_resched_lock(spinlock_t *lock); 1942 extern int __cond_resched_rwlock_read(rwlock_t *lock); 1943 extern int __cond_resched_rwlock_write(rwlock_t *lock); 1944 1945 #define cond_resched_lock(lock) ({ \ 1946 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\ 1947 __cond_resched_lock(lock); \ 1948 }) 1949 1950 #define cond_resched_rwlock_read(lock) ({ \ 1951 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \ 1952 __cond_resched_rwlock_read(lock); \ 1953 }) 1954 1955 #define cond_resched_rwlock_write(lock) ({ \ 1956 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \ 1957 __cond_resched_rwlock_write(lock); \ 1958 }) 1959 1960 static inline void cond_resched_rcu(void) 1961 { 1962 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU) 1963 rcu_read_unlock(); 1964 cond_resched(); 1965 rcu_read_lock(); 1966 #endif 1967 } 1968 1969 /* 1970 * Does a critical section need to be broken due to another 1971 * task waiting?: (technically does not depend on CONFIG_PREEMPTION, 1972 * but a general need for low latency) 1973 */ 1974 static inline int spin_needbreak(spinlock_t *lock) 1975 { 1976 #ifdef CONFIG_PREEMPTION 1977 return spin_is_contended(lock); 1978 #else 1979 return 0; 1980 #endif 1981 } 1982 1983 /* 1984 * Check if a rwlock is contended. 1985 * Returns non-zero if there is another task waiting on the rwlock. 1986 * Returns zero if the lock is not contended or the system / underlying 1987 * rwlock implementation does not support contention detection. 1988 * Technically does not depend on CONFIG_PREEMPTION, but a general need 1989 * for low latency. 1990 */ 1991 static inline int rwlock_needbreak(rwlock_t *lock) 1992 { 1993 #ifdef CONFIG_PREEMPTION 1994 return rwlock_is_contended(lock); 1995 #else 1996 return 0; 1997 #endif 1998 } 1999 2000 static __always_inline bool need_resched(void) 2001 { 2002 return unlikely(tif_need_resched()); 2003 } 2004 2005 /* 2006 * Wrappers for p->thread_info->cpu access. No-op on UP. 2007 */ 2008 #ifdef CONFIG_SMP 2009 2010 static inline unsigned int task_cpu(const struct task_struct *p) 2011 { 2012 #ifdef CONFIG_THREAD_INFO_IN_TASK 2013 return READ_ONCE(p->cpu); 2014 #else 2015 return READ_ONCE(task_thread_info(p)->cpu); 2016 #endif 2017 } 2018 2019 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 2020 2021 #else 2022 2023 static inline unsigned int task_cpu(const struct task_struct *p) 2024 { 2025 return 0; 2026 } 2027 2028 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 2029 { 2030 } 2031 2032 #endif /* CONFIG_SMP */ 2033 2034 extern bool sched_task_on_rq(struct task_struct *p); 2035 2036 /* 2037 * In order to reduce various lock holder preemption latencies provide an 2038 * interface to see if a vCPU is currently running or not. 2039 * 2040 * This allows us to terminate optimistic spin loops and block, analogous to 2041 * the native optimistic spin heuristic of testing if the lock owner task is 2042 * running or not. 2043 */ 2044 #ifndef vcpu_is_preempted 2045 static inline bool vcpu_is_preempted(int cpu) 2046 { 2047 return false; 2048 } 2049 #endif 2050 2051 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 2052 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 2053 2054 #ifndef TASK_SIZE_OF 2055 #define TASK_SIZE_OF(tsk) TASK_SIZE 2056 #endif 2057 2058 #ifdef CONFIG_SMP 2059 /* Returns effective CPU energy utilization, as seen by the scheduler */ 2060 unsigned long sched_cpu_util(int cpu, unsigned long max); 2061 #endif /* CONFIG_SMP */ 2062 2063 #ifdef CONFIG_RSEQ 2064 2065 /* 2066 * Map the event mask on the user-space ABI enum rseq_cs_flags 2067 * for direct mask checks. 2068 */ 2069 enum rseq_event_mask_bits { 2070 RSEQ_EVENT_PREEMPT_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT, 2071 RSEQ_EVENT_SIGNAL_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT, 2072 RSEQ_EVENT_MIGRATE_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT, 2073 }; 2074 2075 enum rseq_event_mask { 2076 RSEQ_EVENT_PREEMPT = (1U << RSEQ_EVENT_PREEMPT_BIT), 2077 RSEQ_EVENT_SIGNAL = (1U << RSEQ_EVENT_SIGNAL_BIT), 2078 RSEQ_EVENT_MIGRATE = (1U << RSEQ_EVENT_MIGRATE_BIT), 2079 }; 2080 2081 static inline void rseq_set_notify_resume(struct task_struct *t) 2082 { 2083 if (t->rseq) 2084 set_tsk_thread_flag(t, TIF_NOTIFY_RESUME); 2085 } 2086 2087 void __rseq_handle_notify_resume(struct ksignal *sig, struct pt_regs *regs); 2088 2089 static inline void rseq_handle_notify_resume(struct ksignal *ksig, 2090 struct pt_regs *regs) 2091 { 2092 if (current->rseq) 2093 __rseq_handle_notify_resume(ksig, regs); 2094 } 2095 2096 static inline void rseq_signal_deliver(struct ksignal *ksig, 2097 struct pt_regs *regs) 2098 { 2099 preempt_disable(); 2100 __set_bit(RSEQ_EVENT_SIGNAL_BIT, ¤t->rseq_event_mask); 2101 preempt_enable(); 2102 rseq_handle_notify_resume(ksig, regs); 2103 } 2104 2105 /* rseq_preempt() requires preemption to be disabled. */ 2106 static inline void rseq_preempt(struct task_struct *t) 2107 { 2108 __set_bit(RSEQ_EVENT_PREEMPT_BIT, &t->rseq_event_mask); 2109 rseq_set_notify_resume(t); 2110 } 2111 2112 /* rseq_migrate() requires preemption to be disabled. */ 2113 static inline void rseq_migrate(struct task_struct *t) 2114 { 2115 __set_bit(RSEQ_EVENT_MIGRATE_BIT, &t->rseq_event_mask); 2116 rseq_set_notify_resume(t); 2117 } 2118 2119 /* 2120 * If parent process has a registered restartable sequences area, the 2121 * child inherits. Unregister rseq for a clone with CLONE_VM set. 2122 */ 2123 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags) 2124 { 2125 if (clone_flags & CLONE_VM) { 2126 t->rseq = NULL; 2127 t->rseq_sig = 0; 2128 t->rseq_event_mask = 0; 2129 } else { 2130 t->rseq = current->rseq; 2131 t->rseq_sig = current->rseq_sig; 2132 t->rseq_event_mask = current->rseq_event_mask; 2133 } 2134 } 2135 2136 static inline void rseq_execve(struct task_struct *t) 2137 { 2138 t->rseq = NULL; 2139 t->rseq_sig = 0; 2140 t->rseq_event_mask = 0; 2141 } 2142 2143 #else 2144 2145 static inline void rseq_set_notify_resume(struct task_struct *t) 2146 { 2147 } 2148 static inline void rseq_handle_notify_resume(struct ksignal *ksig, 2149 struct pt_regs *regs) 2150 { 2151 } 2152 static inline void rseq_signal_deliver(struct ksignal *ksig, 2153 struct pt_regs *regs) 2154 { 2155 } 2156 static inline void rseq_preempt(struct task_struct *t) 2157 { 2158 } 2159 static inline void rseq_migrate(struct task_struct *t) 2160 { 2161 } 2162 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags) 2163 { 2164 } 2165 static inline void rseq_execve(struct task_struct *t) 2166 { 2167 } 2168 2169 #endif 2170 2171 #ifdef CONFIG_DEBUG_RSEQ 2172 2173 void rseq_syscall(struct pt_regs *regs); 2174 2175 #else 2176 2177 static inline void rseq_syscall(struct pt_regs *regs) 2178 { 2179 } 2180 2181 #endif 2182 2183 const struct sched_avg *sched_trace_cfs_rq_avg(struct cfs_rq *cfs_rq); 2184 char *sched_trace_cfs_rq_path(struct cfs_rq *cfs_rq, char *str, int len); 2185 int sched_trace_cfs_rq_cpu(struct cfs_rq *cfs_rq); 2186 2187 const struct sched_avg *sched_trace_rq_avg_rt(struct rq *rq); 2188 const struct sched_avg *sched_trace_rq_avg_dl(struct rq *rq); 2189 const struct sched_avg *sched_trace_rq_avg_irq(struct rq *rq); 2190 2191 int sched_trace_rq_cpu(struct rq *rq); 2192 int sched_trace_rq_cpu_capacity(struct rq *rq); 2193 int sched_trace_rq_nr_running(struct rq *rq); 2194 2195 const struct cpumask *sched_trace_rd_span(struct root_domain *rd); 2196 2197 #ifdef CONFIG_SCHED_CORE 2198 extern void sched_core_free(struct task_struct *tsk); 2199 extern void sched_core_fork(struct task_struct *p); 2200 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type, 2201 unsigned long uaddr); 2202 #else 2203 static inline void sched_core_free(struct task_struct *tsk) { } 2204 static inline void sched_core_fork(struct task_struct *p) { } 2205 #endif 2206 2207 #endif 2208