1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_SCHED_H 3 #define _LINUX_SCHED_H 4 5 /* 6 * Define 'struct task_struct' and provide the main scheduler 7 * APIs (schedule(), wakeup variants, etc.) 8 */ 9 10 #include <uapi/linux/sched.h> 11 12 #include <asm/current.h> 13 #include <asm/processor.h> 14 #include <linux/thread_info.h> 15 #include <linux/preempt.h> 16 #include <linux/cpumask_types.h> 17 18 #include <linux/cache.h> 19 #include <linux/irqflags_types.h> 20 #include <linux/smp_types.h> 21 #include <linux/pid_types.h> 22 #include <linux/sem_types.h> 23 #include <linux/shm.h> 24 #include <linux/kmsan_types.h> 25 #include <linux/mutex_types.h> 26 #include <linux/plist_types.h> 27 #include <linux/hrtimer_types.h> 28 #include <linux/timer_types.h> 29 #include <linux/seccomp_types.h> 30 #include <linux/nodemask_types.h> 31 #include <linux/refcount_types.h> 32 #include <linux/resource.h> 33 #include <linux/latencytop.h> 34 #include <linux/sched/prio.h> 35 #include <linux/sched/types.h> 36 #include <linux/signal_types.h> 37 #include <linux/syscall_user_dispatch_types.h> 38 #include <linux/mm_types_task.h> 39 #include <linux/netdevice_xmit.h> 40 #include <linux/task_io_accounting.h> 41 #include <linux/posix-timers_types.h> 42 #include <linux/restart_block.h> 43 #include <uapi/linux/rseq.h> 44 #include <linux/seqlock_types.h> 45 #include <linux/kcsan.h> 46 #include <linux/rv.h> 47 #include <linux/uidgid_types.h> 48 #include <linux/tracepoint-defs.h> 49 #include <asm/kmap_size.h> 50 51 /* task_struct member predeclarations (sorted alphabetically): */ 52 struct audit_context; 53 struct bio_list; 54 struct blk_plug; 55 struct bpf_local_storage; 56 struct bpf_run_ctx; 57 struct bpf_net_context; 58 struct capture_control; 59 struct cfs_rq; 60 struct fs_struct; 61 struct futex_pi_state; 62 struct io_context; 63 struct io_uring_task; 64 struct mempolicy; 65 struct nameidata; 66 struct nsproxy; 67 struct perf_event_context; 68 struct perf_ctx_data; 69 struct pid_namespace; 70 struct pipe_inode_info; 71 struct rcu_node; 72 struct reclaim_state; 73 struct robust_list_head; 74 struct root_domain; 75 struct rq; 76 struct sched_attr; 77 struct sched_dl_entity; 78 struct seq_file; 79 struct sighand_struct; 80 struct signal_struct; 81 struct task_delay_info; 82 struct task_group; 83 struct task_struct; 84 struct user_event_mm; 85 86 #include <linux/sched/ext.h> 87 88 /* 89 * Task state bitmask. NOTE! These bits are also 90 * encoded in fs/proc/array.c: get_task_state(). 91 * 92 * We have two separate sets of flags: task->__state 93 * is about runnability, while task->exit_state are 94 * about the task exiting. Confusing, but this way 95 * modifying one set can't modify the other one by 96 * mistake. 97 */ 98 99 /* Used in tsk->__state: */ 100 #define TASK_RUNNING 0x00000000 101 #define TASK_INTERRUPTIBLE 0x00000001 102 #define TASK_UNINTERRUPTIBLE 0x00000002 103 #define __TASK_STOPPED 0x00000004 104 #define __TASK_TRACED 0x00000008 105 /* Used in tsk->exit_state: */ 106 #define EXIT_DEAD 0x00000010 107 #define EXIT_ZOMBIE 0x00000020 108 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD) 109 /* Used in tsk->__state again: */ 110 #define TASK_PARKED 0x00000040 111 #define TASK_DEAD 0x00000080 112 #define TASK_WAKEKILL 0x00000100 113 #define TASK_WAKING 0x00000200 114 #define TASK_NOLOAD 0x00000400 115 #define TASK_NEW 0x00000800 116 #define TASK_RTLOCK_WAIT 0x00001000 117 #define TASK_FREEZABLE 0x00002000 118 #define __TASK_FREEZABLE_UNSAFE (0x00004000 * IS_ENABLED(CONFIG_LOCKDEP)) 119 #define TASK_FROZEN 0x00008000 120 #define TASK_STATE_MAX 0x00010000 121 122 #define TASK_ANY (TASK_STATE_MAX-1) 123 124 /* 125 * DO NOT ADD ANY NEW USERS ! 126 */ 127 #define TASK_FREEZABLE_UNSAFE (TASK_FREEZABLE | __TASK_FREEZABLE_UNSAFE) 128 129 /* Convenience macros for the sake of set_current_state: */ 130 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 131 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 132 #define TASK_TRACED __TASK_TRACED 133 134 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD) 135 136 /* Convenience macros for the sake of wake_up(): */ 137 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 138 139 /* get_task_state(): */ 140 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 141 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 142 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \ 143 TASK_PARKED) 144 145 #define task_is_running(task) (READ_ONCE((task)->__state) == TASK_RUNNING) 146 147 #define task_is_traced(task) ((READ_ONCE(task->jobctl) & JOBCTL_TRACED) != 0) 148 #define task_is_stopped(task) ((READ_ONCE(task->jobctl) & JOBCTL_STOPPED) != 0) 149 #define task_is_stopped_or_traced(task) ((READ_ONCE(task->jobctl) & (JOBCTL_STOPPED | JOBCTL_TRACED)) != 0) 150 151 /* 152 * Special states are those that do not use the normal wait-loop pattern. See 153 * the comment with set_special_state(). 154 */ 155 #define is_special_task_state(state) \ 156 ((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | \ 157 TASK_DEAD | TASK_FROZEN)) 158 159 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 160 # define debug_normal_state_change(state_value) \ 161 do { \ 162 WARN_ON_ONCE(is_special_task_state(state_value)); \ 163 current->task_state_change = _THIS_IP_; \ 164 } while (0) 165 166 # define debug_special_state_change(state_value) \ 167 do { \ 168 WARN_ON_ONCE(!is_special_task_state(state_value)); \ 169 current->task_state_change = _THIS_IP_; \ 170 } while (0) 171 172 # define debug_rtlock_wait_set_state() \ 173 do { \ 174 current->saved_state_change = current->task_state_change;\ 175 current->task_state_change = _THIS_IP_; \ 176 } while (0) 177 178 # define debug_rtlock_wait_restore_state() \ 179 do { \ 180 current->task_state_change = current->saved_state_change;\ 181 } while (0) 182 183 #else 184 # define debug_normal_state_change(cond) do { } while (0) 185 # define debug_special_state_change(cond) do { } while (0) 186 # define debug_rtlock_wait_set_state() do { } while (0) 187 # define debug_rtlock_wait_restore_state() do { } while (0) 188 #endif 189 190 #define trace_set_current_state(state_value) \ 191 do { \ 192 if (tracepoint_enabled(sched_set_state_tp)) \ 193 __trace_set_current_state(state_value); \ 194 } while (0) 195 196 /* 197 * set_current_state() includes a barrier so that the write of current->__state 198 * is correctly serialised wrt the caller's subsequent test of whether to 199 * actually sleep: 200 * 201 * for (;;) { 202 * set_current_state(TASK_UNINTERRUPTIBLE); 203 * if (CONDITION) 204 * break; 205 * 206 * schedule(); 207 * } 208 * __set_current_state(TASK_RUNNING); 209 * 210 * If the caller does not need such serialisation (because, for instance, the 211 * CONDITION test and condition change and wakeup are under the same lock) then 212 * use __set_current_state(). 213 * 214 * The above is typically ordered against the wakeup, which does: 215 * 216 * CONDITION = 1; 217 * wake_up_state(p, TASK_UNINTERRUPTIBLE); 218 * 219 * where wake_up_state()/try_to_wake_up() executes a full memory barrier before 220 * accessing p->__state. 221 * 222 * Wakeup will do: if (@state & p->__state) p->__state = TASK_RUNNING, that is, 223 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a 224 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING). 225 * 226 * However, with slightly different timing the wakeup TASK_RUNNING store can 227 * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not 228 * a problem either because that will result in one extra go around the loop 229 * and our @cond test will save the day. 230 * 231 * Also see the comments of try_to_wake_up(). 232 */ 233 #define __set_current_state(state_value) \ 234 do { \ 235 debug_normal_state_change((state_value)); \ 236 trace_set_current_state(state_value); \ 237 WRITE_ONCE(current->__state, (state_value)); \ 238 } while (0) 239 240 #define set_current_state(state_value) \ 241 do { \ 242 debug_normal_state_change((state_value)); \ 243 trace_set_current_state(state_value); \ 244 smp_store_mb(current->__state, (state_value)); \ 245 } while (0) 246 247 /* 248 * set_special_state() should be used for those states when the blocking task 249 * can not use the regular condition based wait-loop. In that case we must 250 * serialize against wakeups such that any possible in-flight TASK_RUNNING 251 * stores will not collide with our state change. 252 */ 253 #define set_special_state(state_value) \ 254 do { \ 255 unsigned long flags; /* may shadow */ \ 256 \ 257 raw_spin_lock_irqsave(¤t->pi_lock, flags); \ 258 debug_special_state_change((state_value)); \ 259 trace_set_current_state(state_value); \ 260 WRITE_ONCE(current->__state, (state_value)); \ 261 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \ 262 } while (0) 263 264 /* 265 * PREEMPT_RT specific variants for "sleeping" spin/rwlocks 266 * 267 * RT's spin/rwlock substitutions are state preserving. The state of the 268 * task when blocking on the lock is saved in task_struct::saved_state and 269 * restored after the lock has been acquired. These operations are 270 * serialized by task_struct::pi_lock against try_to_wake_up(). Any non RT 271 * lock related wakeups while the task is blocked on the lock are 272 * redirected to operate on task_struct::saved_state to ensure that these 273 * are not dropped. On restore task_struct::saved_state is set to 274 * TASK_RUNNING so any wakeup attempt redirected to saved_state will fail. 275 * 276 * The lock operation looks like this: 277 * 278 * current_save_and_set_rtlock_wait_state(); 279 * for (;;) { 280 * if (try_lock()) 281 * break; 282 * raw_spin_unlock_irq(&lock->wait_lock); 283 * schedule_rtlock(); 284 * raw_spin_lock_irq(&lock->wait_lock); 285 * set_current_state(TASK_RTLOCK_WAIT); 286 * } 287 * current_restore_rtlock_saved_state(); 288 */ 289 #define current_save_and_set_rtlock_wait_state() \ 290 do { \ 291 lockdep_assert_irqs_disabled(); \ 292 raw_spin_lock(¤t->pi_lock); \ 293 current->saved_state = current->__state; \ 294 debug_rtlock_wait_set_state(); \ 295 trace_set_current_state(TASK_RTLOCK_WAIT); \ 296 WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT); \ 297 raw_spin_unlock(¤t->pi_lock); \ 298 } while (0); 299 300 #define current_restore_rtlock_saved_state() \ 301 do { \ 302 lockdep_assert_irqs_disabled(); \ 303 raw_spin_lock(¤t->pi_lock); \ 304 debug_rtlock_wait_restore_state(); \ 305 trace_set_current_state(current->saved_state); \ 306 WRITE_ONCE(current->__state, current->saved_state); \ 307 current->saved_state = TASK_RUNNING; \ 308 raw_spin_unlock(¤t->pi_lock); \ 309 } while (0); 310 311 #define get_current_state() READ_ONCE(current->__state) 312 313 /* 314 * Define the task command name length as enum, then it can be visible to 315 * BPF programs. 316 */ 317 enum { 318 TASK_COMM_LEN = 16, 319 }; 320 321 extern void sched_tick(void); 322 323 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 324 325 extern long schedule_timeout(long timeout); 326 extern long schedule_timeout_interruptible(long timeout); 327 extern long schedule_timeout_killable(long timeout); 328 extern long schedule_timeout_uninterruptible(long timeout); 329 extern long schedule_timeout_idle(long timeout); 330 asmlinkage void schedule(void); 331 extern void schedule_preempt_disabled(void); 332 asmlinkage void preempt_schedule_irq(void); 333 #ifdef CONFIG_PREEMPT_RT 334 extern void schedule_rtlock(void); 335 #endif 336 337 extern int __must_check io_schedule_prepare(void); 338 extern void io_schedule_finish(int token); 339 extern long io_schedule_timeout(long timeout); 340 extern void io_schedule(void); 341 342 /* wrapper function to trace from this header file */ 343 DECLARE_TRACEPOINT(sched_set_state_tp); 344 extern void __trace_set_current_state(int state_value); 345 346 /** 347 * struct prev_cputime - snapshot of system and user cputime 348 * @utime: time spent in user mode 349 * @stime: time spent in system mode 350 * @lock: protects the above two fields 351 * 352 * Stores previous user/system time values such that we can guarantee 353 * monotonicity. 354 */ 355 struct prev_cputime { 356 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 357 u64 utime; 358 u64 stime; 359 raw_spinlock_t lock; 360 #endif 361 }; 362 363 enum vtime_state { 364 /* Task is sleeping or running in a CPU with VTIME inactive: */ 365 VTIME_INACTIVE = 0, 366 /* Task is idle */ 367 VTIME_IDLE, 368 /* Task runs in kernelspace in a CPU with VTIME active: */ 369 VTIME_SYS, 370 /* Task runs in userspace in a CPU with VTIME active: */ 371 VTIME_USER, 372 /* Task runs as guests in a CPU with VTIME active: */ 373 VTIME_GUEST, 374 }; 375 376 struct vtime { 377 seqcount_t seqcount; 378 unsigned long long starttime; 379 enum vtime_state state; 380 unsigned int cpu; 381 u64 utime; 382 u64 stime; 383 u64 gtime; 384 }; 385 386 /* 387 * Utilization clamp constraints. 388 * @UCLAMP_MIN: Minimum utilization 389 * @UCLAMP_MAX: Maximum utilization 390 * @UCLAMP_CNT: Utilization clamp constraints count 391 */ 392 enum uclamp_id { 393 UCLAMP_MIN = 0, 394 UCLAMP_MAX, 395 UCLAMP_CNT 396 }; 397 398 #ifdef CONFIG_SMP 399 extern struct root_domain def_root_domain; 400 extern struct mutex sched_domains_mutex; 401 extern void sched_domains_mutex_lock(void); 402 extern void sched_domains_mutex_unlock(void); 403 #else 404 static inline void sched_domains_mutex_lock(void) { } 405 static inline void sched_domains_mutex_unlock(void) { } 406 #endif 407 408 struct sched_param { 409 int sched_priority; 410 }; 411 412 struct sched_info { 413 #ifdef CONFIG_SCHED_INFO 414 /* Cumulative counters: */ 415 416 /* # of times we have run on this CPU: */ 417 unsigned long pcount; 418 419 /* Time spent waiting on a runqueue: */ 420 unsigned long long run_delay; 421 422 /* Max time spent waiting on a runqueue: */ 423 unsigned long long max_run_delay; 424 425 /* Min time spent waiting on a runqueue: */ 426 unsigned long long min_run_delay; 427 428 /* Timestamps: */ 429 430 /* When did we last run on a CPU? */ 431 unsigned long long last_arrival; 432 433 /* When were we last queued to run? */ 434 unsigned long long last_queued; 435 436 #endif /* CONFIG_SCHED_INFO */ 437 }; 438 439 /* 440 * Integer metrics need fixed point arithmetic, e.g., sched/fair 441 * has a few: load, load_avg, util_avg, freq, and capacity. 442 * 443 * We define a basic fixed point arithmetic range, and then formalize 444 * all these metrics based on that basic range. 445 */ 446 # define SCHED_FIXEDPOINT_SHIFT 10 447 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT) 448 449 /* Increase resolution of cpu_capacity calculations */ 450 # define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT 451 # define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) 452 453 struct load_weight { 454 unsigned long weight; 455 u32 inv_weight; 456 }; 457 458 /* 459 * The load/runnable/util_avg accumulates an infinite geometric series 460 * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c). 461 * 462 * [load_avg definition] 463 * 464 * load_avg = runnable% * scale_load_down(load) 465 * 466 * [runnable_avg definition] 467 * 468 * runnable_avg = runnable% * SCHED_CAPACITY_SCALE 469 * 470 * [util_avg definition] 471 * 472 * util_avg = running% * SCHED_CAPACITY_SCALE 473 * 474 * where runnable% is the time ratio that a sched_entity is runnable and 475 * running% the time ratio that a sched_entity is running. 476 * 477 * For cfs_rq, they are the aggregated values of all runnable and blocked 478 * sched_entities. 479 * 480 * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU 481 * capacity scaling. The scaling is done through the rq_clock_pelt that is used 482 * for computing those signals (see update_rq_clock_pelt()) 483 * 484 * N.B., the above ratios (runnable% and running%) themselves are in the 485 * range of [0, 1]. To do fixed point arithmetics, we therefore scale them 486 * to as large a range as necessary. This is for example reflected by 487 * util_avg's SCHED_CAPACITY_SCALE. 488 * 489 * [Overflow issue] 490 * 491 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities 492 * with the highest load (=88761), always runnable on a single cfs_rq, 493 * and should not overflow as the number already hits PID_MAX_LIMIT. 494 * 495 * For all other cases (including 32-bit kernels), struct load_weight's 496 * weight will overflow first before we do, because: 497 * 498 * Max(load_avg) <= Max(load.weight) 499 * 500 * Then it is the load_weight's responsibility to consider overflow 501 * issues. 502 */ 503 struct sched_avg { 504 u64 last_update_time; 505 u64 load_sum; 506 u64 runnable_sum; 507 u32 util_sum; 508 u32 period_contrib; 509 unsigned long load_avg; 510 unsigned long runnable_avg; 511 unsigned long util_avg; 512 unsigned int util_est; 513 } ____cacheline_aligned; 514 515 /* 516 * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg 517 * updates. When a task is dequeued, its util_est should not be updated if its 518 * util_avg has not been updated in the meantime. 519 * This information is mapped into the MSB bit of util_est at dequeue time. 520 * Since max value of util_est for a task is 1024 (PELT util_avg for a task) 521 * it is safe to use MSB. 522 */ 523 #define UTIL_EST_WEIGHT_SHIFT 2 524 #define UTIL_AVG_UNCHANGED 0x80000000 525 526 struct sched_statistics { 527 #ifdef CONFIG_SCHEDSTATS 528 u64 wait_start; 529 u64 wait_max; 530 u64 wait_count; 531 u64 wait_sum; 532 u64 iowait_count; 533 u64 iowait_sum; 534 535 u64 sleep_start; 536 u64 sleep_max; 537 s64 sum_sleep_runtime; 538 539 u64 block_start; 540 u64 block_max; 541 s64 sum_block_runtime; 542 543 s64 exec_max; 544 u64 slice_max; 545 546 u64 nr_migrations_cold; 547 u64 nr_failed_migrations_affine; 548 u64 nr_failed_migrations_running; 549 u64 nr_failed_migrations_hot; 550 u64 nr_forced_migrations; 551 #ifdef CONFIG_NUMA_BALANCING 552 u64 numa_task_migrated; 553 u64 numa_task_swapped; 554 #endif 555 556 u64 nr_wakeups; 557 u64 nr_wakeups_sync; 558 u64 nr_wakeups_migrate; 559 u64 nr_wakeups_local; 560 u64 nr_wakeups_remote; 561 u64 nr_wakeups_affine; 562 u64 nr_wakeups_affine_attempts; 563 u64 nr_wakeups_passive; 564 u64 nr_wakeups_idle; 565 566 #ifdef CONFIG_SCHED_CORE 567 u64 core_forceidle_sum; 568 #endif 569 #endif /* CONFIG_SCHEDSTATS */ 570 } ____cacheline_aligned; 571 572 struct sched_entity { 573 /* For load-balancing: */ 574 struct load_weight load; 575 struct rb_node run_node; 576 u64 deadline; 577 u64 min_vruntime; 578 u64 min_slice; 579 580 struct list_head group_node; 581 unsigned char on_rq; 582 unsigned char sched_delayed; 583 unsigned char rel_deadline; 584 unsigned char custom_slice; 585 /* hole */ 586 587 u64 exec_start; 588 u64 sum_exec_runtime; 589 u64 prev_sum_exec_runtime; 590 u64 vruntime; 591 s64 vlag; 592 u64 slice; 593 594 u64 nr_migrations; 595 596 #ifdef CONFIG_FAIR_GROUP_SCHED 597 int depth; 598 struct sched_entity *parent; 599 /* rq on which this entity is (to be) queued: */ 600 struct cfs_rq *cfs_rq; 601 /* rq "owned" by this entity/group: */ 602 struct cfs_rq *my_q; 603 /* cached value of my_q->h_nr_running */ 604 unsigned long runnable_weight; 605 #endif 606 607 #ifdef CONFIG_SMP 608 /* 609 * Per entity load average tracking. 610 * 611 * Put into separate cache line so it does not 612 * collide with read-mostly values above. 613 */ 614 struct sched_avg avg; 615 #endif 616 }; 617 618 struct sched_rt_entity { 619 struct list_head run_list; 620 unsigned long timeout; 621 unsigned long watchdog_stamp; 622 unsigned int time_slice; 623 unsigned short on_rq; 624 unsigned short on_list; 625 626 struct sched_rt_entity *back; 627 #ifdef CONFIG_RT_GROUP_SCHED 628 struct sched_rt_entity *parent; 629 /* rq on which this entity is (to be) queued: */ 630 struct rt_rq *rt_rq; 631 /* rq "owned" by this entity/group: */ 632 struct rt_rq *my_q; 633 #endif 634 } __randomize_layout; 635 636 typedef bool (*dl_server_has_tasks_f)(struct sched_dl_entity *); 637 typedef struct task_struct *(*dl_server_pick_f)(struct sched_dl_entity *); 638 639 struct sched_dl_entity { 640 struct rb_node rb_node; 641 642 /* 643 * Original scheduling parameters. Copied here from sched_attr 644 * during sched_setattr(), they will remain the same until 645 * the next sched_setattr(). 646 */ 647 u64 dl_runtime; /* Maximum runtime for each instance */ 648 u64 dl_deadline; /* Relative deadline of each instance */ 649 u64 dl_period; /* Separation of two instances (period) */ 650 u64 dl_bw; /* dl_runtime / dl_period */ 651 u64 dl_density; /* dl_runtime / dl_deadline */ 652 653 /* 654 * Actual scheduling parameters. Initialized with the values above, 655 * they are continuously updated during task execution. Note that 656 * the remaining runtime could be < 0 in case we are in overrun. 657 */ 658 s64 runtime; /* Remaining runtime for this instance */ 659 u64 deadline; /* Absolute deadline for this instance */ 660 unsigned int flags; /* Specifying the scheduler behaviour */ 661 662 /* 663 * Some bool flags: 664 * 665 * @dl_throttled tells if we exhausted the runtime. If so, the 666 * task has to wait for a replenishment to be performed at the 667 * next firing of dl_timer. 668 * 669 * @dl_yielded tells if task gave up the CPU before consuming 670 * all its available runtime during the last job. 671 * 672 * @dl_non_contending tells if the task is inactive while still 673 * contributing to the active utilization. In other words, it 674 * indicates if the inactive timer has been armed and its handler 675 * has not been executed yet. This flag is useful to avoid race 676 * conditions between the inactive timer handler and the wakeup 677 * code. 678 * 679 * @dl_overrun tells if the task asked to be informed about runtime 680 * overruns. 681 * 682 * @dl_server tells if this is a server entity. 683 * 684 * @dl_defer tells if this is a deferred or regular server. For 685 * now only defer server exists. 686 * 687 * @dl_defer_armed tells if the deferrable server is waiting 688 * for the replenishment timer to activate it. 689 * 690 * @dl_server_active tells if the dlserver is active(started). 691 * dlserver is started on first cfs enqueue on an idle runqueue 692 * and is stopped when a dequeue results in 0 cfs tasks on the 693 * runqueue. In other words, dlserver is active only when cpu's 694 * runqueue has atleast one cfs task. 695 * 696 * @dl_defer_running tells if the deferrable server is actually 697 * running, skipping the defer phase. 698 */ 699 unsigned int dl_throttled : 1; 700 unsigned int dl_yielded : 1; 701 unsigned int dl_non_contending : 1; 702 unsigned int dl_overrun : 1; 703 unsigned int dl_server : 1; 704 unsigned int dl_server_active : 1; 705 unsigned int dl_defer : 1; 706 unsigned int dl_defer_armed : 1; 707 unsigned int dl_defer_running : 1; 708 709 /* 710 * Bandwidth enforcement timer. Each -deadline task has its 711 * own bandwidth to be enforced, thus we need one timer per task. 712 */ 713 struct hrtimer dl_timer; 714 715 /* 716 * Inactive timer, responsible for decreasing the active utilization 717 * at the "0-lag time". When a -deadline task blocks, it contributes 718 * to GRUB's active utilization until the "0-lag time", hence a 719 * timer is needed to decrease the active utilization at the correct 720 * time. 721 */ 722 struct hrtimer inactive_timer; 723 724 /* 725 * Bits for DL-server functionality. Also see the comment near 726 * dl_server_update(). 727 * 728 * @rq the runqueue this server is for 729 * 730 * @server_has_tasks() returns true if @server_pick return a 731 * runnable task. 732 */ 733 struct rq *rq; 734 dl_server_has_tasks_f server_has_tasks; 735 dl_server_pick_f server_pick_task; 736 737 #ifdef CONFIG_RT_MUTEXES 738 /* 739 * Priority Inheritance. When a DEADLINE scheduling entity is boosted 740 * pi_se points to the donor, otherwise points to the dl_se it belongs 741 * to (the original one/itself). 742 */ 743 struct sched_dl_entity *pi_se; 744 #endif 745 }; 746 747 #ifdef CONFIG_UCLAMP_TASK 748 /* Number of utilization clamp buckets (shorter alias) */ 749 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT 750 751 /* 752 * Utilization clamp for a scheduling entity 753 * @value: clamp value "assigned" to a se 754 * @bucket_id: bucket index corresponding to the "assigned" value 755 * @active: the se is currently refcounted in a rq's bucket 756 * @user_defined: the requested clamp value comes from user-space 757 * 758 * The bucket_id is the index of the clamp bucket matching the clamp value 759 * which is pre-computed and stored to avoid expensive integer divisions from 760 * the fast path. 761 * 762 * The active bit is set whenever a task has got an "effective" value assigned, 763 * which can be different from the clamp value "requested" from user-space. 764 * This allows to know a task is refcounted in the rq's bucket corresponding 765 * to the "effective" bucket_id. 766 * 767 * The user_defined bit is set whenever a task has got a task-specific clamp 768 * value requested from userspace, i.e. the system defaults apply to this task 769 * just as a restriction. This allows to relax default clamps when a less 770 * restrictive task-specific value has been requested, thus allowing to 771 * implement a "nice" semantic. For example, a task running with a 20% 772 * default boost can still drop its own boosting to 0%. 773 */ 774 struct uclamp_se { 775 unsigned int value : bits_per(SCHED_CAPACITY_SCALE); 776 unsigned int bucket_id : bits_per(UCLAMP_BUCKETS); 777 unsigned int active : 1; 778 unsigned int user_defined : 1; 779 }; 780 #endif /* CONFIG_UCLAMP_TASK */ 781 782 union rcu_special { 783 struct { 784 u8 blocked; 785 u8 need_qs; 786 u8 exp_hint; /* Hint for performance. */ 787 u8 need_mb; /* Readers need smp_mb(). */ 788 } b; /* Bits. */ 789 u32 s; /* Set of bits. */ 790 }; 791 792 enum perf_event_task_context { 793 perf_invalid_context = -1, 794 perf_hw_context = 0, 795 perf_sw_context, 796 perf_nr_task_contexts, 797 }; 798 799 /* 800 * Number of contexts where an event can trigger: 801 * task, softirq, hardirq, nmi. 802 */ 803 #define PERF_NR_CONTEXTS 4 804 805 struct wake_q_node { 806 struct wake_q_node *next; 807 }; 808 809 struct kmap_ctrl { 810 #ifdef CONFIG_KMAP_LOCAL 811 int idx; 812 pte_t pteval[KM_MAX_IDX]; 813 #endif 814 }; 815 816 struct task_struct { 817 #ifdef CONFIG_THREAD_INFO_IN_TASK 818 /* 819 * For reasons of header soup (see current_thread_info()), this 820 * must be the first element of task_struct. 821 */ 822 struct thread_info thread_info; 823 #endif 824 unsigned int __state; 825 826 /* saved state for "spinlock sleepers" */ 827 unsigned int saved_state; 828 829 /* 830 * This begins the randomizable portion of task_struct. Only 831 * scheduling-critical items should be added above here. 832 */ 833 randomized_struct_fields_start 834 835 void *stack; 836 refcount_t usage; 837 /* Per task flags (PF_*), defined further below: */ 838 unsigned int flags; 839 unsigned int ptrace; 840 841 #ifdef CONFIG_MEM_ALLOC_PROFILING 842 struct alloc_tag *alloc_tag; 843 #endif 844 845 #ifdef CONFIG_SMP 846 int on_cpu; 847 struct __call_single_node wake_entry; 848 unsigned int wakee_flips; 849 unsigned long wakee_flip_decay_ts; 850 struct task_struct *last_wakee; 851 852 /* 853 * recent_used_cpu is initially set as the last CPU used by a task 854 * that wakes affine another task. Waker/wakee relationships can 855 * push tasks around a CPU where each wakeup moves to the next one. 856 * Tracking a recently used CPU allows a quick search for a recently 857 * used CPU that may be idle. 858 */ 859 int recent_used_cpu; 860 int wake_cpu; 861 #endif 862 int on_rq; 863 864 int prio; 865 int static_prio; 866 int normal_prio; 867 unsigned int rt_priority; 868 869 struct sched_entity se; 870 struct sched_rt_entity rt; 871 struct sched_dl_entity dl; 872 struct sched_dl_entity *dl_server; 873 #ifdef CONFIG_SCHED_CLASS_EXT 874 struct sched_ext_entity scx; 875 #endif 876 const struct sched_class *sched_class; 877 878 #ifdef CONFIG_SCHED_CORE 879 struct rb_node core_node; 880 unsigned long core_cookie; 881 unsigned int core_occupation; 882 #endif 883 884 #ifdef CONFIG_CGROUP_SCHED 885 struct task_group *sched_task_group; 886 #endif 887 888 889 #ifdef CONFIG_UCLAMP_TASK 890 /* 891 * Clamp values requested for a scheduling entity. 892 * Must be updated with task_rq_lock() held. 893 */ 894 struct uclamp_se uclamp_req[UCLAMP_CNT]; 895 /* 896 * Effective clamp values used for a scheduling entity. 897 * Must be updated with task_rq_lock() held. 898 */ 899 struct uclamp_se uclamp[UCLAMP_CNT]; 900 #endif 901 902 struct sched_statistics stats; 903 904 #ifdef CONFIG_PREEMPT_NOTIFIERS 905 /* List of struct preempt_notifier: */ 906 struct hlist_head preempt_notifiers; 907 #endif 908 909 #ifdef CONFIG_BLK_DEV_IO_TRACE 910 unsigned int btrace_seq; 911 #endif 912 913 unsigned int policy; 914 unsigned long max_allowed_capacity; 915 int nr_cpus_allowed; 916 const cpumask_t *cpus_ptr; 917 cpumask_t *user_cpus_ptr; 918 cpumask_t cpus_mask; 919 void *migration_pending; 920 #ifdef CONFIG_SMP 921 unsigned short migration_disabled; 922 #endif 923 unsigned short migration_flags; 924 925 #ifdef CONFIG_PREEMPT_RCU 926 int rcu_read_lock_nesting; 927 union rcu_special rcu_read_unlock_special; 928 struct list_head rcu_node_entry; 929 struct rcu_node *rcu_blocked_node; 930 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 931 932 #ifdef CONFIG_TASKS_RCU 933 unsigned long rcu_tasks_nvcsw; 934 u8 rcu_tasks_holdout; 935 u8 rcu_tasks_idx; 936 int rcu_tasks_idle_cpu; 937 struct list_head rcu_tasks_holdout_list; 938 int rcu_tasks_exit_cpu; 939 struct list_head rcu_tasks_exit_list; 940 #endif /* #ifdef CONFIG_TASKS_RCU */ 941 942 #ifdef CONFIG_TASKS_TRACE_RCU 943 int trc_reader_nesting; 944 int trc_ipi_to_cpu; 945 union rcu_special trc_reader_special; 946 struct list_head trc_holdout_list; 947 struct list_head trc_blkd_node; 948 int trc_blkd_cpu; 949 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */ 950 951 struct sched_info sched_info; 952 953 struct list_head tasks; 954 #ifdef CONFIG_SMP 955 struct plist_node pushable_tasks; 956 struct rb_node pushable_dl_tasks; 957 #endif 958 959 struct mm_struct *mm; 960 struct mm_struct *active_mm; 961 struct address_space *faults_disabled_mapping; 962 963 int exit_state; 964 int exit_code; 965 int exit_signal; 966 /* The signal sent when the parent dies: */ 967 int pdeath_signal; 968 /* JOBCTL_*, siglock protected: */ 969 unsigned long jobctl; 970 971 /* Used for emulating ABI behavior of previous Linux versions: */ 972 unsigned int personality; 973 974 /* Scheduler bits, serialized by scheduler locks: */ 975 unsigned sched_reset_on_fork:1; 976 unsigned sched_contributes_to_load:1; 977 unsigned sched_migrated:1; 978 unsigned sched_task_hot:1; 979 980 /* Force alignment to the next boundary: */ 981 unsigned :0; 982 983 /* Unserialized, strictly 'current' */ 984 985 /* 986 * This field must not be in the scheduler word above due to wakelist 987 * queueing no longer being serialized by p->on_cpu. However: 988 * 989 * p->XXX = X; ttwu() 990 * schedule() if (p->on_rq && ..) // false 991 * smp_mb__after_spinlock(); if (smp_load_acquire(&p->on_cpu) && //true 992 * deactivate_task() ttwu_queue_wakelist()) 993 * p->on_rq = 0; p->sched_remote_wakeup = Y; 994 * 995 * guarantees all stores of 'current' are visible before 996 * ->sched_remote_wakeup gets used, so it can be in this word. 997 */ 998 unsigned sched_remote_wakeup:1; 999 #ifdef CONFIG_RT_MUTEXES 1000 unsigned sched_rt_mutex:1; 1001 #endif 1002 1003 /* Bit to tell TOMOYO we're in execve(): */ 1004 unsigned in_execve:1; 1005 unsigned in_iowait:1; 1006 #ifndef TIF_RESTORE_SIGMASK 1007 unsigned restore_sigmask:1; 1008 #endif 1009 #ifdef CONFIG_MEMCG_V1 1010 unsigned in_user_fault:1; 1011 #endif 1012 #ifdef CONFIG_LRU_GEN 1013 /* whether the LRU algorithm may apply to this access */ 1014 unsigned in_lru_fault:1; 1015 #endif 1016 #ifdef CONFIG_COMPAT_BRK 1017 unsigned brk_randomized:1; 1018 #endif 1019 #ifdef CONFIG_CGROUPS 1020 /* disallow userland-initiated cgroup migration */ 1021 unsigned no_cgroup_migration:1; 1022 /* task is frozen/stopped (used by the cgroup freezer) */ 1023 unsigned frozen:1; 1024 #endif 1025 #ifdef CONFIG_BLK_CGROUP 1026 unsigned use_memdelay:1; 1027 #endif 1028 #ifdef CONFIG_PSI 1029 /* Stalled due to lack of memory */ 1030 unsigned in_memstall:1; 1031 #endif 1032 #ifdef CONFIG_PAGE_OWNER 1033 /* Used by page_owner=on to detect recursion in page tracking. */ 1034 unsigned in_page_owner:1; 1035 #endif 1036 #ifdef CONFIG_EVENTFD 1037 /* Recursion prevention for eventfd_signal() */ 1038 unsigned in_eventfd:1; 1039 #endif 1040 #ifdef CONFIG_ARCH_HAS_CPU_PASID 1041 unsigned pasid_activated:1; 1042 #endif 1043 #ifdef CONFIG_X86_BUS_LOCK_DETECT 1044 unsigned reported_split_lock:1; 1045 #endif 1046 #ifdef CONFIG_TASK_DELAY_ACCT 1047 /* delay due to memory thrashing */ 1048 unsigned in_thrashing:1; 1049 #endif 1050 unsigned in_nf_duplicate:1; 1051 #ifdef CONFIG_PREEMPT_RT 1052 struct netdev_xmit net_xmit; 1053 #endif 1054 unsigned long atomic_flags; /* Flags requiring atomic access. */ 1055 1056 struct restart_block restart_block; 1057 1058 pid_t pid; 1059 pid_t tgid; 1060 1061 #ifdef CONFIG_STACKPROTECTOR 1062 /* Canary value for the -fstack-protector GCC feature: */ 1063 unsigned long stack_canary; 1064 #endif 1065 /* 1066 * Pointers to the (original) parent process, youngest child, younger sibling, 1067 * older sibling, respectively. (p->father can be replaced with 1068 * p->real_parent->pid) 1069 */ 1070 1071 /* Real parent process: */ 1072 struct task_struct __rcu *real_parent; 1073 1074 /* Recipient of SIGCHLD, wait4() reports: */ 1075 struct task_struct __rcu *parent; 1076 1077 /* 1078 * Children/sibling form the list of natural children: 1079 */ 1080 struct list_head children; 1081 struct list_head sibling; 1082 struct task_struct *group_leader; 1083 1084 /* 1085 * 'ptraced' is the list of tasks this task is using ptrace() on. 1086 * 1087 * This includes both natural children and PTRACE_ATTACH targets. 1088 * 'ptrace_entry' is this task's link on the p->parent->ptraced list. 1089 */ 1090 struct list_head ptraced; 1091 struct list_head ptrace_entry; 1092 1093 /* PID/PID hash table linkage. */ 1094 struct pid *thread_pid; 1095 struct hlist_node pid_links[PIDTYPE_MAX]; 1096 struct list_head thread_node; 1097 1098 struct completion *vfork_done; 1099 1100 /* CLONE_CHILD_SETTID: */ 1101 int __user *set_child_tid; 1102 1103 /* CLONE_CHILD_CLEARTID: */ 1104 int __user *clear_child_tid; 1105 1106 /* PF_KTHREAD | PF_IO_WORKER */ 1107 void *worker_private; 1108 1109 u64 utime; 1110 u64 stime; 1111 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME 1112 u64 utimescaled; 1113 u64 stimescaled; 1114 #endif 1115 u64 gtime; 1116 struct prev_cputime prev_cputime; 1117 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1118 struct vtime vtime; 1119 #endif 1120 1121 #ifdef CONFIG_NO_HZ_FULL 1122 atomic_t tick_dep_mask; 1123 #endif 1124 /* Context switch counts: */ 1125 unsigned long nvcsw; 1126 unsigned long nivcsw; 1127 1128 /* Monotonic time in nsecs: */ 1129 u64 start_time; 1130 1131 /* Boot based time in nsecs: */ 1132 u64 start_boottime; 1133 1134 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */ 1135 unsigned long min_flt; 1136 unsigned long maj_flt; 1137 1138 /* Empty if CONFIG_POSIX_CPUTIMERS=n */ 1139 struct posix_cputimers posix_cputimers; 1140 1141 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK 1142 struct posix_cputimers_work posix_cputimers_work; 1143 #endif 1144 1145 /* Process credentials: */ 1146 1147 /* Tracer's credentials at attach: */ 1148 const struct cred __rcu *ptracer_cred; 1149 1150 /* Objective and real subjective task credentials (COW): */ 1151 const struct cred __rcu *real_cred; 1152 1153 /* Effective (overridable) subjective task credentials (COW): */ 1154 const struct cred __rcu *cred; 1155 1156 #ifdef CONFIG_KEYS 1157 /* Cached requested key. */ 1158 struct key *cached_requested_key; 1159 #endif 1160 1161 /* 1162 * executable name, excluding path. 1163 * 1164 * - normally initialized begin_new_exec() 1165 * - set it with set_task_comm() 1166 * - strscpy_pad() to ensure it is always NUL-terminated and 1167 * zero-padded 1168 * - task_lock() to ensure the operation is atomic and the name is 1169 * fully updated. 1170 */ 1171 char comm[TASK_COMM_LEN]; 1172 1173 struct nameidata *nameidata; 1174 1175 #ifdef CONFIG_SYSVIPC 1176 struct sysv_sem sysvsem; 1177 struct sysv_shm sysvshm; 1178 #endif 1179 #ifdef CONFIG_DETECT_HUNG_TASK 1180 unsigned long last_switch_count; 1181 unsigned long last_switch_time; 1182 #endif 1183 /* Filesystem information: */ 1184 struct fs_struct *fs; 1185 1186 /* Open file information: */ 1187 struct files_struct *files; 1188 1189 #ifdef CONFIG_IO_URING 1190 struct io_uring_task *io_uring; 1191 #endif 1192 1193 /* Namespaces: */ 1194 struct nsproxy *nsproxy; 1195 1196 /* Signal handlers: */ 1197 struct signal_struct *signal; 1198 struct sighand_struct __rcu *sighand; 1199 sigset_t blocked; 1200 sigset_t real_blocked; 1201 /* Restored if set_restore_sigmask() was used: */ 1202 sigset_t saved_sigmask; 1203 struct sigpending pending; 1204 unsigned long sas_ss_sp; 1205 size_t sas_ss_size; 1206 unsigned int sas_ss_flags; 1207 1208 struct callback_head *task_works; 1209 1210 #ifdef CONFIG_AUDIT 1211 #ifdef CONFIG_AUDITSYSCALL 1212 struct audit_context *audit_context; 1213 #endif 1214 kuid_t loginuid; 1215 unsigned int sessionid; 1216 #endif 1217 struct seccomp seccomp; 1218 struct syscall_user_dispatch syscall_dispatch; 1219 1220 /* Thread group tracking: */ 1221 u64 parent_exec_id; 1222 u64 self_exec_id; 1223 1224 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */ 1225 spinlock_t alloc_lock; 1226 1227 /* Protection of the PI data structures: */ 1228 raw_spinlock_t pi_lock; 1229 1230 struct wake_q_node wake_q; 1231 1232 #ifdef CONFIG_RT_MUTEXES 1233 /* PI waiters blocked on a rt_mutex held by this task: */ 1234 struct rb_root_cached pi_waiters; 1235 /* Updated under owner's pi_lock and rq lock */ 1236 struct task_struct *pi_top_task; 1237 /* Deadlock detection and priority inheritance handling: */ 1238 struct rt_mutex_waiter *pi_blocked_on; 1239 #endif 1240 1241 #ifdef CONFIG_DEBUG_MUTEXES 1242 /* Mutex deadlock detection: */ 1243 struct mutex_waiter *blocked_on; 1244 #endif 1245 1246 #ifdef CONFIG_DETECT_HUNG_TASK_BLOCKER 1247 /* 1248 * Encoded lock address causing task block (lower 2 bits = type from 1249 * <linux/hung_task.h>). Accessed via hung_task_*() helpers. 1250 */ 1251 unsigned long blocker; 1252 #endif 1253 1254 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1255 int non_block_count; 1256 #endif 1257 1258 #ifdef CONFIG_TRACE_IRQFLAGS 1259 struct irqtrace_events irqtrace; 1260 unsigned int hardirq_threaded; 1261 u64 hardirq_chain_key; 1262 int softirqs_enabled; 1263 int softirq_context; 1264 int irq_config; 1265 #endif 1266 #ifdef CONFIG_PREEMPT_RT 1267 int softirq_disable_cnt; 1268 #endif 1269 1270 #ifdef CONFIG_LOCKDEP 1271 # define MAX_LOCK_DEPTH 48UL 1272 u64 curr_chain_key; 1273 int lockdep_depth; 1274 unsigned int lockdep_recursion; 1275 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1276 #endif 1277 1278 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP) 1279 unsigned int in_ubsan; 1280 #endif 1281 1282 /* Journalling filesystem info: */ 1283 void *journal_info; 1284 1285 /* Stacked block device info: */ 1286 struct bio_list *bio_list; 1287 1288 /* Stack plugging: */ 1289 struct blk_plug *plug; 1290 1291 /* VM state: */ 1292 struct reclaim_state *reclaim_state; 1293 1294 struct io_context *io_context; 1295 1296 #ifdef CONFIG_COMPACTION 1297 struct capture_control *capture_control; 1298 #endif 1299 /* Ptrace state: */ 1300 unsigned long ptrace_message; 1301 kernel_siginfo_t *last_siginfo; 1302 1303 struct task_io_accounting ioac; 1304 #ifdef CONFIG_PSI 1305 /* Pressure stall state */ 1306 unsigned int psi_flags; 1307 #endif 1308 #ifdef CONFIG_TASK_XACCT 1309 /* Accumulated RSS usage: */ 1310 u64 acct_rss_mem1; 1311 /* Accumulated virtual memory usage: */ 1312 u64 acct_vm_mem1; 1313 /* stime + utime since last update: */ 1314 u64 acct_timexpd; 1315 #endif 1316 #ifdef CONFIG_CPUSETS 1317 /* Protected by ->alloc_lock: */ 1318 nodemask_t mems_allowed; 1319 /* Sequence number to catch updates: */ 1320 seqcount_spinlock_t mems_allowed_seq; 1321 int cpuset_mem_spread_rotor; 1322 #endif 1323 #ifdef CONFIG_CGROUPS 1324 /* Control Group info protected by css_set_lock: */ 1325 struct css_set __rcu *cgroups; 1326 /* cg_list protected by css_set_lock and tsk->alloc_lock: */ 1327 struct list_head cg_list; 1328 #endif 1329 #ifdef CONFIG_X86_CPU_RESCTRL 1330 u32 closid; 1331 u32 rmid; 1332 #endif 1333 #ifdef CONFIG_FUTEX 1334 struct robust_list_head __user *robust_list; 1335 #ifdef CONFIG_COMPAT 1336 struct compat_robust_list_head __user *compat_robust_list; 1337 #endif 1338 struct list_head pi_state_list; 1339 struct futex_pi_state *pi_state_cache; 1340 struct mutex futex_exit_mutex; 1341 unsigned int futex_state; 1342 #endif 1343 #ifdef CONFIG_PERF_EVENTS 1344 u8 perf_recursion[PERF_NR_CONTEXTS]; 1345 struct perf_event_context *perf_event_ctxp; 1346 struct mutex perf_event_mutex; 1347 struct list_head perf_event_list; 1348 struct perf_ctx_data __rcu *perf_ctx_data; 1349 #endif 1350 #ifdef CONFIG_DEBUG_PREEMPT 1351 unsigned long preempt_disable_ip; 1352 #endif 1353 #ifdef CONFIG_NUMA 1354 /* Protected by alloc_lock: */ 1355 struct mempolicy *mempolicy; 1356 short il_prev; 1357 u8 il_weight; 1358 short pref_node_fork; 1359 #endif 1360 #ifdef CONFIG_NUMA_BALANCING 1361 int numa_scan_seq; 1362 unsigned int numa_scan_period; 1363 unsigned int numa_scan_period_max; 1364 int numa_preferred_nid; 1365 unsigned long numa_migrate_retry; 1366 /* Migration stamp: */ 1367 u64 node_stamp; 1368 u64 last_task_numa_placement; 1369 u64 last_sum_exec_runtime; 1370 struct callback_head numa_work; 1371 1372 /* 1373 * This pointer is only modified for current in syscall and 1374 * pagefault context (and for tasks being destroyed), so it can be read 1375 * from any of the following contexts: 1376 * - RCU read-side critical section 1377 * - current->numa_group from everywhere 1378 * - task's runqueue locked, task not running 1379 */ 1380 struct numa_group __rcu *numa_group; 1381 1382 /* 1383 * numa_faults is an array split into four regions: 1384 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer 1385 * in this precise order. 1386 * 1387 * faults_memory: Exponential decaying average of faults on a per-node 1388 * basis. Scheduling placement decisions are made based on these 1389 * counts. The values remain static for the duration of a PTE scan. 1390 * faults_cpu: Track the nodes the process was running on when a NUMA 1391 * hinting fault was incurred. 1392 * faults_memory_buffer and faults_cpu_buffer: Record faults per node 1393 * during the current scan window. When the scan completes, the counts 1394 * in faults_memory and faults_cpu decay and these values are copied. 1395 */ 1396 unsigned long *numa_faults; 1397 unsigned long total_numa_faults; 1398 1399 /* 1400 * numa_faults_locality tracks if faults recorded during the last 1401 * scan window were remote/local or failed to migrate. The task scan 1402 * period is adapted based on the locality of the faults with different 1403 * weights depending on whether they were shared or private faults 1404 */ 1405 unsigned long numa_faults_locality[3]; 1406 1407 unsigned long numa_pages_migrated; 1408 #endif /* CONFIG_NUMA_BALANCING */ 1409 1410 #ifdef CONFIG_RSEQ 1411 struct rseq __user *rseq; 1412 u32 rseq_len; 1413 u32 rseq_sig; 1414 /* 1415 * RmW on rseq_event_mask must be performed atomically 1416 * with respect to preemption. 1417 */ 1418 unsigned long rseq_event_mask; 1419 # ifdef CONFIG_DEBUG_RSEQ 1420 /* 1421 * This is a place holder to save a copy of the rseq fields for 1422 * validation of read-only fields. The struct rseq has a 1423 * variable-length array at the end, so it cannot be used 1424 * directly. Reserve a size large enough for the known fields. 1425 */ 1426 char rseq_fields[sizeof(struct rseq)]; 1427 # endif 1428 #endif 1429 1430 #ifdef CONFIG_SCHED_MM_CID 1431 int mm_cid; /* Current cid in mm */ 1432 int last_mm_cid; /* Most recent cid in mm */ 1433 int migrate_from_cpu; 1434 int mm_cid_active; /* Whether cid bitmap is active */ 1435 struct callback_head cid_work; 1436 #endif 1437 1438 struct tlbflush_unmap_batch tlb_ubc; 1439 1440 /* Cache last used pipe for splice(): */ 1441 struct pipe_inode_info *splice_pipe; 1442 1443 struct page_frag task_frag; 1444 1445 #ifdef CONFIG_TASK_DELAY_ACCT 1446 struct task_delay_info *delays; 1447 #endif 1448 1449 #ifdef CONFIG_FAULT_INJECTION 1450 int make_it_fail; 1451 unsigned int fail_nth; 1452 #endif 1453 /* 1454 * When (nr_dirtied >= nr_dirtied_pause), it's time to call 1455 * balance_dirty_pages() for a dirty throttling pause: 1456 */ 1457 int nr_dirtied; 1458 int nr_dirtied_pause; 1459 /* Start of a write-and-pause period: */ 1460 unsigned long dirty_paused_when; 1461 1462 #ifdef CONFIG_LATENCYTOP 1463 int latency_record_count; 1464 struct latency_record latency_record[LT_SAVECOUNT]; 1465 #endif 1466 /* 1467 * Time slack values; these are used to round up poll() and 1468 * select() etc timeout values. These are in nanoseconds. 1469 */ 1470 u64 timer_slack_ns; 1471 u64 default_timer_slack_ns; 1472 1473 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) 1474 unsigned int kasan_depth; 1475 #endif 1476 1477 #ifdef CONFIG_KCSAN 1478 struct kcsan_ctx kcsan_ctx; 1479 #ifdef CONFIG_TRACE_IRQFLAGS 1480 struct irqtrace_events kcsan_save_irqtrace; 1481 #endif 1482 #ifdef CONFIG_KCSAN_WEAK_MEMORY 1483 int kcsan_stack_depth; 1484 #endif 1485 #endif 1486 1487 #ifdef CONFIG_KMSAN 1488 struct kmsan_ctx kmsan_ctx; 1489 #endif 1490 1491 #if IS_ENABLED(CONFIG_KUNIT) 1492 struct kunit *kunit_test; 1493 #endif 1494 1495 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1496 /* Index of current stored address in ret_stack: */ 1497 int curr_ret_stack; 1498 int curr_ret_depth; 1499 1500 /* Stack of return addresses for return function tracing: */ 1501 unsigned long *ret_stack; 1502 1503 /* Timestamp for last schedule: */ 1504 unsigned long long ftrace_timestamp; 1505 unsigned long long ftrace_sleeptime; 1506 1507 /* 1508 * Number of functions that haven't been traced 1509 * because of depth overrun: 1510 */ 1511 atomic_t trace_overrun; 1512 1513 /* Pause tracing: */ 1514 atomic_t tracing_graph_pause; 1515 #endif 1516 1517 #ifdef CONFIG_TRACING 1518 /* Bitmask and counter of trace recursion: */ 1519 unsigned long trace_recursion; 1520 #endif /* CONFIG_TRACING */ 1521 1522 #ifdef CONFIG_KCOV 1523 /* See kernel/kcov.c for more details. */ 1524 1525 /* Coverage collection mode enabled for this task (0 if disabled): */ 1526 unsigned int kcov_mode; 1527 1528 /* Size of the kcov_area: */ 1529 unsigned int kcov_size; 1530 1531 /* Buffer for coverage collection: */ 1532 void *kcov_area; 1533 1534 /* KCOV descriptor wired with this task or NULL: */ 1535 struct kcov *kcov; 1536 1537 /* KCOV common handle for remote coverage collection: */ 1538 u64 kcov_handle; 1539 1540 /* KCOV sequence number: */ 1541 int kcov_sequence; 1542 1543 /* Collect coverage from softirq context: */ 1544 unsigned int kcov_softirq; 1545 #endif 1546 1547 #ifdef CONFIG_MEMCG_V1 1548 struct mem_cgroup *memcg_in_oom; 1549 #endif 1550 1551 #ifdef CONFIG_MEMCG 1552 /* Number of pages to reclaim on returning to userland: */ 1553 unsigned int memcg_nr_pages_over_high; 1554 1555 /* Used by memcontrol for targeted memcg charge: */ 1556 struct mem_cgroup *active_memcg; 1557 1558 /* Cache for current->cgroups->memcg->objcg lookups: */ 1559 struct obj_cgroup *objcg; 1560 #endif 1561 1562 #ifdef CONFIG_BLK_CGROUP 1563 struct gendisk *throttle_disk; 1564 #endif 1565 1566 #ifdef CONFIG_UPROBES 1567 struct uprobe_task *utask; 1568 #endif 1569 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1570 unsigned int sequential_io; 1571 unsigned int sequential_io_avg; 1572 #endif 1573 struct kmap_ctrl kmap_ctrl; 1574 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1575 unsigned long task_state_change; 1576 # ifdef CONFIG_PREEMPT_RT 1577 unsigned long saved_state_change; 1578 # endif 1579 #endif 1580 struct rcu_head rcu; 1581 refcount_t rcu_users; 1582 int pagefault_disabled; 1583 #ifdef CONFIG_MMU 1584 struct task_struct *oom_reaper_list; 1585 struct timer_list oom_reaper_timer; 1586 #endif 1587 #ifdef CONFIG_VMAP_STACK 1588 struct vm_struct *stack_vm_area; 1589 #endif 1590 #ifdef CONFIG_THREAD_INFO_IN_TASK 1591 /* A live task holds one reference: */ 1592 refcount_t stack_refcount; 1593 #endif 1594 #ifdef CONFIG_LIVEPATCH 1595 int patch_state; 1596 #endif 1597 #ifdef CONFIG_SECURITY 1598 /* Used by LSM modules for access restriction: */ 1599 void *security; 1600 #endif 1601 #ifdef CONFIG_BPF_SYSCALL 1602 /* Used by BPF task local storage */ 1603 struct bpf_local_storage __rcu *bpf_storage; 1604 /* Used for BPF run context */ 1605 struct bpf_run_ctx *bpf_ctx; 1606 #endif 1607 /* Used by BPF for per-TASK xdp storage */ 1608 struct bpf_net_context *bpf_net_context; 1609 1610 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK 1611 unsigned long lowest_stack; 1612 unsigned long prev_lowest_stack; 1613 #endif 1614 1615 #ifdef CONFIG_X86_MCE 1616 void __user *mce_vaddr; 1617 __u64 mce_kflags; 1618 u64 mce_addr; 1619 __u64 mce_ripv : 1, 1620 mce_whole_page : 1, 1621 __mce_reserved : 62; 1622 struct callback_head mce_kill_me; 1623 int mce_count; 1624 #endif 1625 1626 #ifdef CONFIG_KRETPROBES 1627 struct llist_head kretprobe_instances; 1628 #endif 1629 #ifdef CONFIG_RETHOOK 1630 struct llist_head rethooks; 1631 #endif 1632 1633 #ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH 1634 /* 1635 * If L1D flush is supported on mm context switch 1636 * then we use this callback head to queue kill work 1637 * to kill tasks that are not running on SMT disabled 1638 * cores 1639 */ 1640 struct callback_head l1d_flush_kill; 1641 #endif 1642 1643 #ifdef CONFIG_RV 1644 /* 1645 * Per-task RV monitor. Nowadays fixed in RV_PER_TASK_MONITORS. 1646 * If we find justification for more monitors, we can think 1647 * about adding more or developing a dynamic method. So far, 1648 * none of these are justified. 1649 */ 1650 union rv_task_monitor rv[RV_PER_TASK_MONITORS]; 1651 #endif 1652 1653 #ifdef CONFIG_USER_EVENTS 1654 struct user_event_mm *user_event_mm; 1655 #endif 1656 1657 /* CPU-specific state of this task: */ 1658 struct thread_struct thread; 1659 1660 /* 1661 * New fields for task_struct should be added above here, so that 1662 * they are included in the randomized portion of task_struct. 1663 */ 1664 randomized_struct_fields_end 1665 } __attribute__ ((aligned (64))); 1666 1667 #define TASK_REPORT_IDLE (TASK_REPORT + 1) 1668 #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1) 1669 1670 static inline unsigned int __task_state_index(unsigned int tsk_state, 1671 unsigned int tsk_exit_state) 1672 { 1673 unsigned int state = (tsk_state | tsk_exit_state) & TASK_REPORT; 1674 1675 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX); 1676 1677 if ((tsk_state & TASK_IDLE) == TASK_IDLE) 1678 state = TASK_REPORT_IDLE; 1679 1680 /* 1681 * We're lying here, but rather than expose a completely new task state 1682 * to userspace, we can make this appear as if the task has gone through 1683 * a regular rt_mutex_lock() call. 1684 * Report frozen tasks as uninterruptible. 1685 */ 1686 if ((tsk_state & TASK_RTLOCK_WAIT) || (tsk_state & TASK_FROZEN)) 1687 state = TASK_UNINTERRUPTIBLE; 1688 1689 return fls(state); 1690 } 1691 1692 static inline unsigned int task_state_index(struct task_struct *tsk) 1693 { 1694 return __task_state_index(READ_ONCE(tsk->__state), tsk->exit_state); 1695 } 1696 1697 static inline char task_index_to_char(unsigned int state) 1698 { 1699 static const char state_char[] = "RSDTtXZPI"; 1700 1701 BUILD_BUG_ON(TASK_REPORT_MAX * 2 != 1 << (sizeof(state_char) - 1)); 1702 1703 return state_char[state]; 1704 } 1705 1706 static inline char task_state_to_char(struct task_struct *tsk) 1707 { 1708 return task_index_to_char(task_state_index(tsk)); 1709 } 1710 1711 extern struct pid *cad_pid; 1712 1713 /* 1714 * Per process flags 1715 */ 1716 #define PF_VCPU 0x00000001 /* I'm a virtual CPU */ 1717 #define PF_IDLE 0x00000002 /* I am an IDLE thread */ 1718 #define PF_EXITING 0x00000004 /* Getting shut down */ 1719 #define PF_POSTCOREDUMP 0x00000008 /* Coredumps should ignore this task */ 1720 #define PF_IO_WORKER 0x00000010 /* Task is an IO worker */ 1721 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 1722 #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */ 1723 #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */ 1724 #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */ 1725 #define PF_DUMPCORE 0x00000200 /* Dumped core */ 1726 #define PF_SIGNALED 0x00000400 /* Killed by a signal */ 1727 #define PF_MEMALLOC 0x00000800 /* Allocating memory to free memory. See memalloc_noreclaim_save() */ 1728 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */ 1729 #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */ 1730 #define PF_USER_WORKER 0x00004000 /* Kernel thread cloned from userspace thread */ 1731 #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */ 1732 #define PF_KCOMPACTD 0x00010000 /* I am kcompactd */ 1733 #define PF_KSWAPD 0x00020000 /* I am kswapd */ 1734 #define PF_MEMALLOC_NOFS 0x00040000 /* All allocations inherit GFP_NOFS. See memalloc_nfs_save() */ 1735 #define PF_MEMALLOC_NOIO 0x00080000 /* All allocations inherit GFP_NOIO. See memalloc_noio_save() */ 1736 #define PF_LOCAL_THROTTLE 0x00100000 /* Throttle writes only against the bdi I write to, 1737 * I am cleaning dirty pages from some other bdi. */ 1738 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 1739 #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */ 1740 #define PF__HOLE__00800000 0x00800000 1741 #define PF__HOLE__01000000 0x01000000 1742 #define PF__HOLE__02000000 0x02000000 1743 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */ 1744 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 1745 #define PF_MEMALLOC_PIN 0x10000000 /* Allocations constrained to zones which allow long term pinning. 1746 * See memalloc_pin_save() */ 1747 #define PF_BLOCK_TS 0x20000000 /* plug has ts that needs updating */ 1748 #define PF__HOLE__40000000 0x40000000 1749 #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */ 1750 1751 /* 1752 * Only the _current_ task can read/write to tsk->flags, but other 1753 * tasks can access tsk->flags in readonly mode for example 1754 * with tsk_used_math (like during threaded core dumping). 1755 * There is however an exception to this rule during ptrace 1756 * or during fork: the ptracer task is allowed to write to the 1757 * child->flags of its traced child (same goes for fork, the parent 1758 * can write to the child->flags), because we're guaranteed the 1759 * child is not running and in turn not changing child->flags 1760 * at the same time the parent does it. 1761 */ 1762 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1763 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1764 #define clear_used_math() clear_stopped_child_used_math(current) 1765 #define set_used_math() set_stopped_child_used_math(current) 1766 1767 #define conditional_stopped_child_used_math(condition, child) \ 1768 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1769 1770 #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current) 1771 1772 #define copy_to_stopped_child_used_math(child) \ 1773 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1774 1775 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1776 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1777 #define used_math() tsk_used_math(current) 1778 1779 static __always_inline bool is_percpu_thread(void) 1780 { 1781 #ifdef CONFIG_SMP 1782 return (current->flags & PF_NO_SETAFFINITY) && 1783 (current->nr_cpus_allowed == 1); 1784 #else 1785 return true; 1786 #endif 1787 } 1788 1789 /* Per-process atomic flags. */ 1790 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */ 1791 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */ 1792 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */ 1793 #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */ 1794 #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/ 1795 #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */ 1796 #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */ 1797 #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */ 1798 1799 #define TASK_PFA_TEST(name, func) \ 1800 static inline bool task_##func(struct task_struct *p) \ 1801 { return test_bit(PFA_##name, &p->atomic_flags); } 1802 1803 #define TASK_PFA_SET(name, func) \ 1804 static inline void task_set_##func(struct task_struct *p) \ 1805 { set_bit(PFA_##name, &p->atomic_flags); } 1806 1807 #define TASK_PFA_CLEAR(name, func) \ 1808 static inline void task_clear_##func(struct task_struct *p) \ 1809 { clear_bit(PFA_##name, &p->atomic_flags); } 1810 1811 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs) 1812 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs) 1813 1814 TASK_PFA_TEST(SPREAD_PAGE, spread_page) 1815 TASK_PFA_SET(SPREAD_PAGE, spread_page) 1816 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page) 1817 1818 TASK_PFA_TEST(SPREAD_SLAB, spread_slab) 1819 TASK_PFA_SET(SPREAD_SLAB, spread_slab) 1820 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab) 1821 1822 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable) 1823 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable) 1824 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable) 1825 1826 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1827 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1828 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1829 1830 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1831 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1832 1833 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable) 1834 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable) 1835 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable) 1836 1837 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1838 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1839 1840 static inline void 1841 current_restore_flags(unsigned long orig_flags, unsigned long flags) 1842 { 1843 current->flags &= ~flags; 1844 current->flags |= orig_flags & flags; 1845 } 1846 1847 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 1848 extern int task_can_attach(struct task_struct *p); 1849 extern int dl_bw_alloc(int cpu, u64 dl_bw); 1850 extern void dl_bw_free(int cpu, u64 dl_bw); 1851 #ifdef CONFIG_SMP 1852 1853 /* do_set_cpus_allowed() - consider using set_cpus_allowed_ptr() instead */ 1854 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask); 1855 1856 /** 1857 * set_cpus_allowed_ptr - set CPU affinity mask of a task 1858 * @p: the task 1859 * @new_mask: CPU affinity mask 1860 * 1861 * Return: zero if successful, or a negative error code 1862 */ 1863 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask); 1864 extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node); 1865 extern void release_user_cpus_ptr(struct task_struct *p); 1866 extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask); 1867 extern void force_compatible_cpus_allowed_ptr(struct task_struct *p); 1868 extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p); 1869 #else 1870 static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) 1871 { 1872 } 1873 static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask) 1874 { 1875 /* Opencoded cpumask_test_cpu(0, new_mask) to avoid dependency on cpumask.h */ 1876 if ((*cpumask_bits(new_mask) & 1) == 0) 1877 return -EINVAL; 1878 return 0; 1879 } 1880 static inline int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node) 1881 { 1882 if (src->user_cpus_ptr) 1883 return -EINVAL; 1884 return 0; 1885 } 1886 static inline void release_user_cpus_ptr(struct task_struct *p) 1887 { 1888 WARN_ON(p->user_cpus_ptr); 1889 } 1890 1891 static inline int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask) 1892 { 1893 return 0; 1894 } 1895 #endif 1896 1897 extern int yield_to(struct task_struct *p, bool preempt); 1898 extern void set_user_nice(struct task_struct *p, long nice); 1899 extern int task_prio(const struct task_struct *p); 1900 1901 /** 1902 * task_nice - return the nice value of a given task. 1903 * @p: the task in question. 1904 * 1905 * Return: The nice value [ -20 ... 0 ... 19 ]. 1906 */ 1907 static inline int task_nice(const struct task_struct *p) 1908 { 1909 return PRIO_TO_NICE((p)->static_prio); 1910 } 1911 1912 extern int can_nice(const struct task_struct *p, const int nice); 1913 extern int task_curr(const struct task_struct *p); 1914 extern int idle_cpu(int cpu); 1915 extern int available_idle_cpu(int cpu); 1916 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *); 1917 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *); 1918 extern void sched_set_fifo(struct task_struct *p); 1919 extern void sched_set_fifo_low(struct task_struct *p); 1920 extern void sched_set_normal(struct task_struct *p, int nice); 1921 extern int sched_setattr(struct task_struct *, const struct sched_attr *); 1922 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *); 1923 extern struct task_struct *idle_task(int cpu); 1924 1925 /** 1926 * is_idle_task - is the specified task an idle task? 1927 * @p: the task in question. 1928 * 1929 * Return: 1 if @p is an idle task. 0 otherwise. 1930 */ 1931 static __always_inline bool is_idle_task(const struct task_struct *p) 1932 { 1933 return !!(p->flags & PF_IDLE); 1934 } 1935 1936 extern struct task_struct *curr_task(int cpu); 1937 extern void ia64_set_curr_task(int cpu, struct task_struct *p); 1938 1939 void yield(void); 1940 1941 union thread_union { 1942 struct task_struct task; 1943 #ifndef CONFIG_THREAD_INFO_IN_TASK 1944 struct thread_info thread_info; 1945 #endif 1946 unsigned long stack[THREAD_SIZE/sizeof(long)]; 1947 }; 1948 1949 #ifndef CONFIG_THREAD_INFO_IN_TASK 1950 extern struct thread_info init_thread_info; 1951 #endif 1952 1953 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)]; 1954 1955 #ifdef CONFIG_THREAD_INFO_IN_TASK 1956 # define task_thread_info(task) (&(task)->thread_info) 1957 #else 1958 # define task_thread_info(task) ((struct thread_info *)(task)->stack) 1959 #endif 1960 1961 /* 1962 * find a task by one of its numerical ids 1963 * 1964 * find_task_by_pid_ns(): 1965 * finds a task by its pid in the specified namespace 1966 * find_task_by_vpid(): 1967 * finds a task by its virtual pid 1968 * 1969 * see also find_vpid() etc in include/linux/pid.h 1970 */ 1971 1972 extern struct task_struct *find_task_by_vpid(pid_t nr); 1973 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns); 1974 1975 /* 1976 * find a task by its virtual pid and get the task struct 1977 */ 1978 extern struct task_struct *find_get_task_by_vpid(pid_t nr); 1979 1980 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 1981 extern int wake_up_process(struct task_struct *tsk); 1982 extern void wake_up_new_task(struct task_struct *tsk); 1983 1984 #ifdef CONFIG_SMP 1985 extern void kick_process(struct task_struct *tsk); 1986 #else 1987 static inline void kick_process(struct task_struct *tsk) { } 1988 #endif 1989 1990 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); 1991 #define set_task_comm(tsk, from) ({ \ 1992 BUILD_BUG_ON(sizeof(from) != TASK_COMM_LEN); \ 1993 __set_task_comm(tsk, from, false); \ 1994 }) 1995 1996 /* 1997 * - Why not use task_lock()? 1998 * User space can randomly change their names anyway, so locking for readers 1999 * doesn't make sense. For writers, locking is probably necessary, as a race 2000 * condition could lead to long-term mixed results. 2001 * The strscpy_pad() in __set_task_comm() can ensure that the task comm is 2002 * always NUL-terminated and zero-padded. Therefore the race condition between 2003 * reader and writer is not an issue. 2004 * 2005 * - BUILD_BUG_ON() can help prevent the buf from being truncated. 2006 * Since the callers don't perform any return value checks, this safeguard is 2007 * necessary. 2008 */ 2009 #define get_task_comm(buf, tsk) ({ \ 2010 BUILD_BUG_ON(sizeof(buf) < TASK_COMM_LEN); \ 2011 strscpy_pad(buf, (tsk)->comm); \ 2012 buf; \ 2013 }) 2014 2015 #ifdef CONFIG_SMP 2016 static __always_inline void scheduler_ipi(void) 2017 { 2018 /* 2019 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting 2020 * TIF_NEED_RESCHED remotely (for the first time) will also send 2021 * this IPI. 2022 */ 2023 preempt_fold_need_resched(); 2024 } 2025 #else 2026 static inline void scheduler_ipi(void) { } 2027 #endif 2028 2029 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state); 2030 2031 /* 2032 * Set thread flags in other task's structures. 2033 * See asm/thread_info.h for TIF_xxxx flags available: 2034 */ 2035 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 2036 { 2037 set_ti_thread_flag(task_thread_info(tsk), flag); 2038 } 2039 2040 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2041 { 2042 clear_ti_thread_flag(task_thread_info(tsk), flag); 2043 } 2044 2045 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag, 2046 bool value) 2047 { 2048 update_ti_thread_flag(task_thread_info(tsk), flag, value); 2049 } 2050 2051 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 2052 { 2053 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 2054 } 2055 2056 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2057 { 2058 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 2059 } 2060 2061 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 2062 { 2063 return test_ti_thread_flag(task_thread_info(tsk), flag); 2064 } 2065 2066 static inline void set_tsk_need_resched(struct task_struct *tsk) 2067 { 2068 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2069 } 2070 2071 static inline void clear_tsk_need_resched(struct task_struct *tsk) 2072 { 2073 atomic_long_andnot(_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY, 2074 (atomic_long_t *)&task_thread_info(tsk)->flags); 2075 } 2076 2077 static inline int test_tsk_need_resched(struct task_struct *tsk) 2078 { 2079 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 2080 } 2081 2082 /* 2083 * cond_resched() and cond_resched_lock(): latency reduction via 2084 * explicit rescheduling in places that are safe. The return 2085 * value indicates whether a reschedule was done in fact. 2086 * cond_resched_lock() will drop the spinlock before scheduling, 2087 */ 2088 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) 2089 extern int __cond_resched(void); 2090 2091 #if defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL) 2092 2093 DECLARE_STATIC_CALL(cond_resched, __cond_resched); 2094 2095 static __always_inline int _cond_resched(void) 2096 { 2097 return static_call_mod(cond_resched)(); 2098 } 2099 2100 #elif defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY) 2101 2102 extern int dynamic_cond_resched(void); 2103 2104 static __always_inline int _cond_resched(void) 2105 { 2106 return dynamic_cond_resched(); 2107 } 2108 2109 #else /* !CONFIG_PREEMPTION */ 2110 2111 static inline int _cond_resched(void) 2112 { 2113 return __cond_resched(); 2114 } 2115 2116 #endif /* PREEMPT_DYNAMIC && CONFIG_HAVE_PREEMPT_DYNAMIC_CALL */ 2117 2118 #else /* CONFIG_PREEMPTION && !CONFIG_PREEMPT_DYNAMIC */ 2119 2120 static inline int _cond_resched(void) 2121 { 2122 return 0; 2123 } 2124 2125 #endif /* !CONFIG_PREEMPTION || CONFIG_PREEMPT_DYNAMIC */ 2126 2127 #define cond_resched() ({ \ 2128 __might_resched(__FILE__, __LINE__, 0); \ 2129 _cond_resched(); \ 2130 }) 2131 2132 extern int __cond_resched_lock(spinlock_t *lock); 2133 extern int __cond_resched_rwlock_read(rwlock_t *lock); 2134 extern int __cond_resched_rwlock_write(rwlock_t *lock); 2135 2136 #define MIGHT_RESCHED_RCU_SHIFT 8 2137 #define MIGHT_RESCHED_PREEMPT_MASK ((1U << MIGHT_RESCHED_RCU_SHIFT) - 1) 2138 2139 #ifndef CONFIG_PREEMPT_RT 2140 /* 2141 * Non RT kernels have an elevated preempt count due to the held lock, 2142 * but are not allowed to be inside a RCU read side critical section 2143 */ 2144 # define PREEMPT_LOCK_RESCHED_OFFSETS PREEMPT_LOCK_OFFSET 2145 #else 2146 /* 2147 * spin/rw_lock() on RT implies rcu_read_lock(). The might_sleep() check in 2148 * cond_resched*lock() has to take that into account because it checks for 2149 * preempt_count() and rcu_preempt_depth(). 2150 */ 2151 # define PREEMPT_LOCK_RESCHED_OFFSETS \ 2152 (PREEMPT_LOCK_OFFSET + (1U << MIGHT_RESCHED_RCU_SHIFT)) 2153 #endif 2154 2155 #define cond_resched_lock(lock) ({ \ 2156 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ 2157 __cond_resched_lock(lock); \ 2158 }) 2159 2160 #define cond_resched_rwlock_read(lock) ({ \ 2161 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ 2162 __cond_resched_rwlock_read(lock); \ 2163 }) 2164 2165 #define cond_resched_rwlock_write(lock) ({ \ 2166 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ 2167 __cond_resched_rwlock_write(lock); \ 2168 }) 2169 2170 static __always_inline bool need_resched(void) 2171 { 2172 return unlikely(tif_need_resched()); 2173 } 2174 2175 /* 2176 * Wrappers for p->thread_info->cpu access. No-op on UP. 2177 */ 2178 #ifdef CONFIG_SMP 2179 2180 static inline unsigned int task_cpu(const struct task_struct *p) 2181 { 2182 return READ_ONCE(task_thread_info(p)->cpu); 2183 } 2184 2185 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 2186 2187 #else 2188 2189 static inline unsigned int task_cpu(const struct task_struct *p) 2190 { 2191 return 0; 2192 } 2193 2194 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 2195 { 2196 } 2197 2198 #endif /* CONFIG_SMP */ 2199 2200 static inline bool task_is_runnable(struct task_struct *p) 2201 { 2202 return p->on_rq && !p->se.sched_delayed; 2203 } 2204 2205 extern bool sched_task_on_rq(struct task_struct *p); 2206 extern unsigned long get_wchan(struct task_struct *p); 2207 extern struct task_struct *cpu_curr_snapshot(int cpu); 2208 2209 #include <linux/spinlock.h> 2210 2211 /* 2212 * In order to reduce various lock holder preemption latencies provide an 2213 * interface to see if a vCPU is currently running or not. 2214 * 2215 * This allows us to terminate optimistic spin loops and block, analogous to 2216 * the native optimistic spin heuristic of testing if the lock owner task is 2217 * running or not. 2218 */ 2219 #ifndef vcpu_is_preempted 2220 static inline bool vcpu_is_preempted(int cpu) 2221 { 2222 return false; 2223 } 2224 #endif 2225 2226 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 2227 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 2228 2229 #ifndef TASK_SIZE_OF 2230 #define TASK_SIZE_OF(tsk) TASK_SIZE 2231 #endif 2232 2233 #ifdef CONFIG_SMP 2234 static inline bool owner_on_cpu(struct task_struct *owner) 2235 { 2236 /* 2237 * As lock holder preemption issue, we both skip spinning if 2238 * task is not on cpu or its cpu is preempted 2239 */ 2240 return READ_ONCE(owner->on_cpu) && !vcpu_is_preempted(task_cpu(owner)); 2241 } 2242 2243 /* Returns effective CPU energy utilization, as seen by the scheduler */ 2244 unsigned long sched_cpu_util(int cpu); 2245 #endif /* CONFIG_SMP */ 2246 2247 #ifdef CONFIG_SCHED_CORE 2248 extern void sched_core_free(struct task_struct *tsk); 2249 extern void sched_core_fork(struct task_struct *p); 2250 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type, 2251 unsigned long uaddr); 2252 extern int sched_core_idle_cpu(int cpu); 2253 #else 2254 static inline void sched_core_free(struct task_struct *tsk) { } 2255 static inline void sched_core_fork(struct task_struct *p) { } 2256 static inline int sched_core_idle_cpu(int cpu) { return idle_cpu(cpu); } 2257 #endif 2258 2259 extern void sched_set_stop_task(int cpu, struct task_struct *stop); 2260 2261 #ifdef CONFIG_MEM_ALLOC_PROFILING 2262 static __always_inline struct alloc_tag *alloc_tag_save(struct alloc_tag *tag) 2263 { 2264 swap(current->alloc_tag, tag); 2265 return tag; 2266 } 2267 2268 static __always_inline void alloc_tag_restore(struct alloc_tag *tag, struct alloc_tag *old) 2269 { 2270 #ifdef CONFIG_MEM_ALLOC_PROFILING_DEBUG 2271 WARN(current->alloc_tag != tag, "current->alloc_tag was changed:\n"); 2272 #endif 2273 current->alloc_tag = old; 2274 } 2275 #else 2276 #define alloc_tag_save(_tag) NULL 2277 #define alloc_tag_restore(_tag, _old) do {} while (0) 2278 #endif 2279 2280 #endif 2281