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/livepatch_sched.h> 48 #include <linux/uidgid_types.h> 49 #include <linux/tracepoint-defs.h> 50 #include <asm/kmap_size.h> 51 52 /* task_struct member predeclarations (sorted alphabetically): */ 53 struct audit_context; 54 struct bio_list; 55 struct blk_plug; 56 struct bpf_local_storage; 57 struct bpf_run_ctx; 58 struct bpf_net_context; 59 struct capture_control; 60 struct cfs_rq; 61 struct fs_struct; 62 struct futex_pi_state; 63 struct io_context; 64 struct io_uring_task; 65 struct mempolicy; 66 struct nameidata; 67 struct nsproxy; 68 struct perf_event_context; 69 struct perf_ctx_data; 70 struct pid_namespace; 71 struct pipe_inode_info; 72 struct rcu_node; 73 struct reclaim_state; 74 struct robust_list_head; 75 struct root_domain; 76 struct rq; 77 struct sched_attr; 78 struct sched_dl_entity; 79 struct seq_file; 80 struct sighand_struct; 81 struct signal_struct; 82 struct task_delay_info; 83 struct task_group; 84 struct task_struct; 85 struct user_event_mm; 86 87 #include <linux/sched/ext.h> 88 89 /* 90 * Task state bitmask. NOTE! These bits are also 91 * encoded in fs/proc/array.c: get_task_state(). 92 * 93 * We have two separate sets of flags: task->__state 94 * is about runnability, while task->exit_state are 95 * about the task exiting. Confusing, but this way 96 * modifying one set can't modify the other one by 97 * mistake. 98 */ 99 100 /* Used in tsk->__state: */ 101 #define TASK_RUNNING 0x00000000 102 #define TASK_INTERRUPTIBLE 0x00000001 103 #define TASK_UNINTERRUPTIBLE 0x00000002 104 #define __TASK_STOPPED 0x00000004 105 #define __TASK_TRACED 0x00000008 106 /* Used in tsk->exit_state: */ 107 #define EXIT_DEAD 0x00000010 108 #define EXIT_ZOMBIE 0x00000020 109 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD) 110 /* Used in tsk->__state again: */ 111 #define TASK_PARKED 0x00000040 112 #define TASK_DEAD 0x00000080 113 #define TASK_WAKEKILL 0x00000100 114 #define TASK_WAKING 0x00000200 115 #define TASK_NOLOAD 0x00000400 116 #define TASK_NEW 0x00000800 117 #define TASK_RTLOCK_WAIT 0x00001000 118 #define TASK_FREEZABLE 0x00002000 119 #define __TASK_FREEZABLE_UNSAFE (0x00004000 * IS_ENABLED(CONFIG_LOCKDEP)) 120 #define TASK_FROZEN 0x00008000 121 #define TASK_STATE_MAX 0x00010000 122 123 #define TASK_ANY (TASK_STATE_MAX-1) 124 125 /* 126 * DO NOT ADD ANY NEW USERS ! 127 */ 128 #define TASK_FREEZABLE_UNSAFE (TASK_FREEZABLE | __TASK_FREEZABLE_UNSAFE) 129 130 /* Convenience macros for the sake of set_current_state: */ 131 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) 132 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) 133 #define TASK_TRACED __TASK_TRACED 134 135 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD) 136 137 /* Convenience macros for the sake of wake_up(): */ 138 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) 139 140 /* get_task_state(): */ 141 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ 142 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \ 143 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \ 144 TASK_PARKED) 145 146 #define task_is_running(task) (READ_ONCE((task)->__state) == TASK_RUNNING) 147 148 #define task_is_traced(task) ((READ_ONCE(task->jobctl) & JOBCTL_TRACED) != 0) 149 #define task_is_stopped(task) ((READ_ONCE(task->jobctl) & JOBCTL_STOPPED) != 0) 150 #define task_is_stopped_or_traced(task) ((READ_ONCE(task->jobctl) & (JOBCTL_STOPPED | JOBCTL_TRACED)) != 0) 151 152 /* 153 * Special states are those that do not use the normal wait-loop pattern. See 154 * the comment with set_special_state(). 155 */ 156 #define is_special_task_state(state) \ 157 ((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | \ 158 TASK_DEAD | TASK_FROZEN)) 159 160 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 161 # define debug_normal_state_change(state_value) \ 162 do { \ 163 WARN_ON_ONCE(is_special_task_state(state_value)); \ 164 current->task_state_change = _THIS_IP_; \ 165 } while (0) 166 167 # define debug_special_state_change(state_value) \ 168 do { \ 169 WARN_ON_ONCE(!is_special_task_state(state_value)); \ 170 current->task_state_change = _THIS_IP_; \ 171 } while (0) 172 173 # define debug_rtlock_wait_set_state() \ 174 do { \ 175 current->saved_state_change = current->task_state_change;\ 176 current->task_state_change = _THIS_IP_; \ 177 } while (0) 178 179 # define debug_rtlock_wait_restore_state() \ 180 do { \ 181 current->task_state_change = current->saved_state_change;\ 182 } while (0) 183 184 #else 185 # define debug_normal_state_change(cond) do { } while (0) 186 # define debug_special_state_change(cond) do { } while (0) 187 # define debug_rtlock_wait_set_state() do { } while (0) 188 # define debug_rtlock_wait_restore_state() do { } while (0) 189 #endif 190 191 #define trace_set_current_state(state_value) \ 192 do { \ 193 if (tracepoint_enabled(sched_set_state_tp)) \ 194 __trace_set_current_state(state_value); \ 195 } while (0) 196 197 /* 198 * set_current_state() includes a barrier so that the write of current->__state 199 * is correctly serialised wrt the caller's subsequent test of whether to 200 * actually sleep: 201 * 202 * for (;;) { 203 * set_current_state(TASK_UNINTERRUPTIBLE); 204 * if (CONDITION) 205 * break; 206 * 207 * schedule(); 208 * } 209 * __set_current_state(TASK_RUNNING); 210 * 211 * If the caller does not need such serialisation (because, for instance, the 212 * CONDITION test and condition change and wakeup are under the same lock) then 213 * use __set_current_state(). 214 * 215 * The above is typically ordered against the wakeup, which does: 216 * 217 * CONDITION = 1; 218 * wake_up_state(p, TASK_UNINTERRUPTIBLE); 219 * 220 * where wake_up_state()/try_to_wake_up() executes a full memory barrier before 221 * accessing p->__state. 222 * 223 * Wakeup will do: if (@state & p->__state) p->__state = TASK_RUNNING, that is, 224 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a 225 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING). 226 * 227 * However, with slightly different timing the wakeup TASK_RUNNING store can 228 * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not 229 * a problem either because that will result in one extra go around the loop 230 * and our @cond test will save the day. 231 * 232 * Also see the comments of try_to_wake_up(). 233 */ 234 #define __set_current_state(state_value) \ 235 do { \ 236 debug_normal_state_change((state_value)); \ 237 trace_set_current_state(state_value); \ 238 WRITE_ONCE(current->__state, (state_value)); \ 239 } while (0) 240 241 #define set_current_state(state_value) \ 242 do { \ 243 debug_normal_state_change((state_value)); \ 244 trace_set_current_state(state_value); \ 245 smp_store_mb(current->__state, (state_value)); \ 246 } while (0) 247 248 /* 249 * set_special_state() should be used for those states when the blocking task 250 * can not use the regular condition based wait-loop. In that case we must 251 * serialize against wakeups such that any possible in-flight TASK_RUNNING 252 * stores will not collide with our state change. 253 */ 254 #define set_special_state(state_value) \ 255 do { \ 256 unsigned long flags; /* may shadow */ \ 257 \ 258 raw_spin_lock_irqsave(¤t->pi_lock, flags); \ 259 debug_special_state_change((state_value)); \ 260 trace_set_current_state(state_value); \ 261 WRITE_ONCE(current->__state, (state_value)); \ 262 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \ 263 } while (0) 264 265 /* 266 * PREEMPT_RT specific variants for "sleeping" spin/rwlocks 267 * 268 * RT's spin/rwlock substitutions are state preserving. The state of the 269 * task when blocking on the lock is saved in task_struct::saved_state and 270 * restored after the lock has been acquired. These operations are 271 * serialized by task_struct::pi_lock against try_to_wake_up(). Any non RT 272 * lock related wakeups while the task is blocked on the lock are 273 * redirected to operate on task_struct::saved_state to ensure that these 274 * are not dropped. On restore task_struct::saved_state is set to 275 * TASK_RUNNING so any wakeup attempt redirected to saved_state will fail. 276 * 277 * The lock operation looks like this: 278 * 279 * current_save_and_set_rtlock_wait_state(); 280 * for (;;) { 281 * if (try_lock()) 282 * break; 283 * raw_spin_unlock_irq(&lock->wait_lock); 284 * schedule_rtlock(); 285 * raw_spin_lock_irq(&lock->wait_lock); 286 * set_current_state(TASK_RTLOCK_WAIT); 287 * } 288 * current_restore_rtlock_saved_state(); 289 */ 290 #define current_save_and_set_rtlock_wait_state() \ 291 do { \ 292 lockdep_assert_irqs_disabled(); \ 293 raw_spin_lock(¤t->pi_lock); \ 294 current->saved_state = current->__state; \ 295 debug_rtlock_wait_set_state(); \ 296 trace_set_current_state(TASK_RTLOCK_WAIT); \ 297 WRITE_ONCE(current->__state, TASK_RTLOCK_WAIT); \ 298 raw_spin_unlock(¤t->pi_lock); \ 299 } while (0); 300 301 #define current_restore_rtlock_saved_state() \ 302 do { \ 303 lockdep_assert_irqs_disabled(); \ 304 raw_spin_lock(¤t->pi_lock); \ 305 debug_rtlock_wait_restore_state(); \ 306 trace_set_current_state(current->saved_state); \ 307 WRITE_ONCE(current->__state, current->saved_state); \ 308 current->saved_state = TASK_RUNNING; \ 309 raw_spin_unlock(¤t->pi_lock); \ 310 } while (0); 311 312 #define get_current_state() READ_ONCE(current->__state) 313 314 /* 315 * Define the task command name length as enum, then it can be visible to 316 * BPF programs. 317 */ 318 enum { 319 TASK_COMM_LEN = 16, 320 }; 321 322 extern void sched_tick(void); 323 324 #define MAX_SCHEDULE_TIMEOUT LONG_MAX 325 326 extern long schedule_timeout(long timeout); 327 extern long schedule_timeout_interruptible(long timeout); 328 extern long schedule_timeout_killable(long timeout); 329 extern long schedule_timeout_uninterruptible(long timeout); 330 extern long schedule_timeout_idle(long timeout); 331 asmlinkage void schedule(void); 332 extern void schedule_preempt_disabled(void); 333 asmlinkage void preempt_schedule_irq(void); 334 #ifdef CONFIG_PREEMPT_RT 335 extern void schedule_rtlock(void); 336 #endif 337 338 extern int __must_check io_schedule_prepare(void); 339 extern void io_schedule_finish(int token); 340 extern long io_schedule_timeout(long timeout); 341 extern void io_schedule(void); 342 343 /* wrapper function to trace from this header file */ 344 DECLARE_TRACEPOINT(sched_set_state_tp); 345 extern void __trace_set_current_state(int state_value); 346 347 /** 348 * struct prev_cputime - snapshot of system and user cputime 349 * @utime: time spent in user mode 350 * @stime: time spent in system mode 351 * @lock: protects the above two fields 352 * 353 * Stores previous user/system time values such that we can guarantee 354 * monotonicity. 355 */ 356 struct prev_cputime { 357 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE 358 u64 utime; 359 u64 stime; 360 raw_spinlock_t lock; 361 #endif 362 }; 363 364 enum vtime_state { 365 /* Task is sleeping or running in a CPU with VTIME inactive: */ 366 VTIME_INACTIVE = 0, 367 /* Task is idle */ 368 VTIME_IDLE, 369 /* Task runs in kernelspace in a CPU with VTIME active: */ 370 VTIME_SYS, 371 /* Task runs in userspace in a CPU with VTIME active: */ 372 VTIME_USER, 373 /* Task runs as guests in a CPU with VTIME active: */ 374 VTIME_GUEST, 375 }; 376 377 struct vtime { 378 seqcount_t seqcount; 379 unsigned long long starttime; 380 enum vtime_state state; 381 unsigned int cpu; 382 u64 utime; 383 u64 stime; 384 u64 gtime; 385 }; 386 387 /* 388 * Utilization clamp constraints. 389 * @UCLAMP_MIN: Minimum utilization 390 * @UCLAMP_MAX: Maximum utilization 391 * @UCLAMP_CNT: Utilization clamp constraints count 392 */ 393 enum uclamp_id { 394 UCLAMP_MIN = 0, 395 UCLAMP_MAX, 396 UCLAMP_CNT 397 }; 398 399 #ifdef CONFIG_SMP 400 extern struct root_domain def_root_domain; 401 extern struct mutex sched_domains_mutex; 402 extern void sched_domains_mutex_lock(void); 403 extern void sched_domains_mutex_unlock(void); 404 #else 405 static inline void sched_domains_mutex_lock(void) { } 406 static inline void sched_domains_mutex_unlock(void) { } 407 #endif 408 409 struct sched_param { 410 int sched_priority; 411 }; 412 413 struct sched_info { 414 #ifdef CONFIG_SCHED_INFO 415 /* Cumulative counters: */ 416 417 /* # of times we have run on this CPU: */ 418 unsigned long pcount; 419 420 /* Time spent waiting on a runqueue: */ 421 unsigned long long run_delay; 422 423 /* Max time spent waiting on a runqueue: */ 424 unsigned long long max_run_delay; 425 426 /* Min time spent waiting on a runqueue: */ 427 unsigned long long min_run_delay; 428 429 /* Timestamps: */ 430 431 /* When did we last run on a CPU? */ 432 unsigned long long last_arrival; 433 434 /* When were we last queued to run? */ 435 unsigned long long last_queued; 436 437 #endif /* CONFIG_SCHED_INFO */ 438 }; 439 440 /* 441 * Integer metrics need fixed point arithmetic, e.g., sched/fair 442 * has a few: load, load_avg, util_avg, freq, and capacity. 443 * 444 * We define a basic fixed point arithmetic range, and then formalize 445 * all these metrics based on that basic range. 446 */ 447 # define SCHED_FIXEDPOINT_SHIFT 10 448 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT) 449 450 /* Increase resolution of cpu_capacity calculations */ 451 # define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT 452 # define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT) 453 454 struct load_weight { 455 unsigned long weight; 456 u32 inv_weight; 457 }; 458 459 /* 460 * The load/runnable/util_avg accumulates an infinite geometric series 461 * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c). 462 * 463 * [load_avg definition] 464 * 465 * load_avg = runnable% * scale_load_down(load) 466 * 467 * [runnable_avg definition] 468 * 469 * runnable_avg = runnable% * SCHED_CAPACITY_SCALE 470 * 471 * [util_avg definition] 472 * 473 * util_avg = running% * SCHED_CAPACITY_SCALE 474 * 475 * where runnable% is the time ratio that a sched_entity is runnable and 476 * running% the time ratio that a sched_entity is running. 477 * 478 * For cfs_rq, they are the aggregated values of all runnable and blocked 479 * sched_entities. 480 * 481 * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU 482 * capacity scaling. The scaling is done through the rq_clock_pelt that is used 483 * for computing those signals (see update_rq_clock_pelt()) 484 * 485 * N.B., the above ratios (runnable% and running%) themselves are in the 486 * range of [0, 1]. To do fixed point arithmetics, we therefore scale them 487 * to as large a range as necessary. This is for example reflected by 488 * util_avg's SCHED_CAPACITY_SCALE. 489 * 490 * [Overflow issue] 491 * 492 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities 493 * with the highest load (=88761), always runnable on a single cfs_rq, 494 * and should not overflow as the number already hits PID_MAX_LIMIT. 495 * 496 * For all other cases (including 32-bit kernels), struct load_weight's 497 * weight will overflow first before we do, because: 498 * 499 * Max(load_avg) <= Max(load.weight) 500 * 501 * Then it is the load_weight's responsibility to consider overflow 502 * issues. 503 */ 504 struct sched_avg { 505 u64 last_update_time; 506 u64 load_sum; 507 u64 runnable_sum; 508 u32 util_sum; 509 u32 period_contrib; 510 unsigned long load_avg; 511 unsigned long runnable_avg; 512 unsigned long util_avg; 513 unsigned int util_est; 514 } ____cacheline_aligned; 515 516 /* 517 * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg 518 * updates. When a task is dequeued, its util_est should not be updated if its 519 * util_avg has not been updated in the meantime. 520 * This information is mapped into the MSB bit of util_est at dequeue time. 521 * Since max value of util_est for a task is 1024 (PELT util_avg for a task) 522 * it is safe to use MSB. 523 */ 524 #define UTIL_EST_WEIGHT_SHIFT 2 525 #define UTIL_AVG_UNCHANGED 0x80000000 526 527 struct sched_statistics { 528 #ifdef CONFIG_SCHEDSTATS 529 u64 wait_start; 530 u64 wait_max; 531 u64 wait_count; 532 u64 wait_sum; 533 u64 iowait_count; 534 u64 iowait_sum; 535 536 u64 sleep_start; 537 u64 sleep_max; 538 s64 sum_sleep_runtime; 539 540 u64 block_start; 541 u64 block_max; 542 s64 sum_block_runtime; 543 544 s64 exec_max; 545 u64 slice_max; 546 547 u64 nr_migrations_cold; 548 u64 nr_failed_migrations_affine; 549 u64 nr_failed_migrations_running; 550 u64 nr_failed_migrations_hot; 551 u64 nr_forced_migrations; 552 553 u64 nr_wakeups; 554 u64 nr_wakeups_sync; 555 u64 nr_wakeups_migrate; 556 u64 nr_wakeups_local; 557 u64 nr_wakeups_remote; 558 u64 nr_wakeups_affine; 559 u64 nr_wakeups_affine_attempts; 560 u64 nr_wakeups_passive; 561 u64 nr_wakeups_idle; 562 563 #ifdef CONFIG_SCHED_CORE 564 u64 core_forceidle_sum; 565 #endif 566 #endif /* CONFIG_SCHEDSTATS */ 567 } ____cacheline_aligned; 568 569 struct sched_entity { 570 /* For load-balancing: */ 571 struct load_weight load; 572 struct rb_node run_node; 573 u64 deadline; 574 u64 min_vruntime; 575 u64 min_slice; 576 577 struct list_head group_node; 578 unsigned char on_rq; 579 unsigned char sched_delayed; 580 unsigned char rel_deadline; 581 unsigned char custom_slice; 582 /* hole */ 583 584 u64 exec_start; 585 u64 sum_exec_runtime; 586 u64 prev_sum_exec_runtime; 587 u64 vruntime; 588 s64 vlag; 589 u64 slice; 590 591 u64 nr_migrations; 592 593 #ifdef CONFIG_FAIR_GROUP_SCHED 594 int depth; 595 struct sched_entity *parent; 596 /* rq on which this entity is (to be) queued: */ 597 struct cfs_rq *cfs_rq; 598 /* rq "owned" by this entity/group: */ 599 struct cfs_rq *my_q; 600 /* cached value of my_q->h_nr_running */ 601 unsigned long runnable_weight; 602 #endif 603 604 #ifdef CONFIG_SMP 605 /* 606 * Per entity load average tracking. 607 * 608 * Put into separate cache line so it does not 609 * collide with read-mostly values above. 610 */ 611 struct sched_avg avg; 612 #endif 613 }; 614 615 struct sched_rt_entity { 616 struct list_head run_list; 617 unsigned long timeout; 618 unsigned long watchdog_stamp; 619 unsigned int time_slice; 620 unsigned short on_rq; 621 unsigned short on_list; 622 623 struct sched_rt_entity *back; 624 #ifdef CONFIG_RT_GROUP_SCHED 625 struct sched_rt_entity *parent; 626 /* rq on which this entity is (to be) queued: */ 627 struct rt_rq *rt_rq; 628 /* rq "owned" by this entity/group: */ 629 struct rt_rq *my_q; 630 #endif 631 } __randomize_layout; 632 633 typedef bool (*dl_server_has_tasks_f)(struct sched_dl_entity *); 634 typedef struct task_struct *(*dl_server_pick_f)(struct sched_dl_entity *); 635 636 struct sched_dl_entity { 637 struct rb_node rb_node; 638 639 /* 640 * Original scheduling parameters. Copied here from sched_attr 641 * during sched_setattr(), they will remain the same until 642 * the next sched_setattr(). 643 */ 644 u64 dl_runtime; /* Maximum runtime for each instance */ 645 u64 dl_deadline; /* Relative deadline of each instance */ 646 u64 dl_period; /* Separation of two instances (period) */ 647 u64 dl_bw; /* dl_runtime / dl_period */ 648 u64 dl_density; /* dl_runtime / dl_deadline */ 649 650 /* 651 * Actual scheduling parameters. Initialized with the values above, 652 * they are continuously updated during task execution. Note that 653 * the remaining runtime could be < 0 in case we are in overrun. 654 */ 655 s64 runtime; /* Remaining runtime for this instance */ 656 u64 deadline; /* Absolute deadline for this instance */ 657 unsigned int flags; /* Specifying the scheduler behaviour */ 658 659 /* 660 * Some bool flags: 661 * 662 * @dl_throttled tells if we exhausted the runtime. If so, the 663 * task has to wait for a replenishment to be performed at the 664 * next firing of dl_timer. 665 * 666 * @dl_yielded tells if task gave up the CPU before consuming 667 * all its available runtime during the last job. 668 * 669 * @dl_non_contending tells if the task is inactive while still 670 * contributing to the active utilization. In other words, it 671 * indicates if the inactive timer has been armed and its handler 672 * has not been executed yet. This flag is useful to avoid race 673 * conditions between the inactive timer handler and the wakeup 674 * code. 675 * 676 * @dl_overrun tells if the task asked to be informed about runtime 677 * overruns. 678 * 679 * @dl_server tells if this is a server entity. 680 * 681 * @dl_defer tells if this is a deferred or regular server. For 682 * now only defer server exists. 683 * 684 * @dl_defer_armed tells if the deferrable server is waiting 685 * for the replenishment timer to activate it. 686 * 687 * @dl_server_active tells if the dlserver is active(started). 688 * dlserver is started on first cfs enqueue on an idle runqueue 689 * and is stopped when a dequeue results in 0 cfs tasks on the 690 * runqueue. In other words, dlserver is active only when cpu's 691 * runqueue has atleast one cfs task. 692 * 693 * @dl_defer_running tells if the deferrable server is actually 694 * running, skipping the defer phase. 695 */ 696 unsigned int dl_throttled : 1; 697 unsigned int dl_yielded : 1; 698 unsigned int dl_non_contending : 1; 699 unsigned int dl_overrun : 1; 700 unsigned int dl_server : 1; 701 unsigned int dl_server_active : 1; 702 unsigned int dl_defer : 1; 703 unsigned int dl_defer_armed : 1; 704 unsigned int dl_defer_running : 1; 705 706 /* 707 * Bandwidth enforcement timer. Each -deadline task has its 708 * own bandwidth to be enforced, thus we need one timer per task. 709 */ 710 struct hrtimer dl_timer; 711 712 /* 713 * Inactive timer, responsible for decreasing the active utilization 714 * at the "0-lag time". When a -deadline task blocks, it contributes 715 * to GRUB's active utilization until the "0-lag time", hence a 716 * timer is needed to decrease the active utilization at the correct 717 * time. 718 */ 719 struct hrtimer inactive_timer; 720 721 /* 722 * Bits for DL-server functionality. Also see the comment near 723 * dl_server_update(). 724 * 725 * @rq the runqueue this server is for 726 * 727 * @server_has_tasks() returns true if @server_pick return a 728 * runnable task. 729 */ 730 struct rq *rq; 731 dl_server_has_tasks_f server_has_tasks; 732 dl_server_pick_f server_pick_task; 733 734 #ifdef CONFIG_RT_MUTEXES 735 /* 736 * Priority Inheritance. When a DEADLINE scheduling entity is boosted 737 * pi_se points to the donor, otherwise points to the dl_se it belongs 738 * to (the original one/itself). 739 */ 740 struct sched_dl_entity *pi_se; 741 #endif 742 }; 743 744 #ifdef CONFIG_UCLAMP_TASK 745 /* Number of utilization clamp buckets (shorter alias) */ 746 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT 747 748 /* 749 * Utilization clamp for a scheduling entity 750 * @value: clamp value "assigned" to a se 751 * @bucket_id: bucket index corresponding to the "assigned" value 752 * @active: the se is currently refcounted in a rq's bucket 753 * @user_defined: the requested clamp value comes from user-space 754 * 755 * The bucket_id is the index of the clamp bucket matching the clamp value 756 * which is pre-computed and stored to avoid expensive integer divisions from 757 * the fast path. 758 * 759 * The active bit is set whenever a task has got an "effective" value assigned, 760 * which can be different from the clamp value "requested" from user-space. 761 * This allows to know a task is refcounted in the rq's bucket corresponding 762 * to the "effective" bucket_id. 763 * 764 * The user_defined bit is set whenever a task has got a task-specific clamp 765 * value requested from userspace, i.e. the system defaults apply to this task 766 * just as a restriction. This allows to relax default clamps when a less 767 * restrictive task-specific value has been requested, thus allowing to 768 * implement a "nice" semantic. For example, a task running with a 20% 769 * default boost can still drop its own boosting to 0%. 770 */ 771 struct uclamp_se { 772 unsigned int value : bits_per(SCHED_CAPACITY_SCALE); 773 unsigned int bucket_id : bits_per(UCLAMP_BUCKETS); 774 unsigned int active : 1; 775 unsigned int user_defined : 1; 776 }; 777 #endif /* CONFIG_UCLAMP_TASK */ 778 779 union rcu_special { 780 struct { 781 u8 blocked; 782 u8 need_qs; 783 u8 exp_hint; /* Hint for performance. */ 784 u8 need_mb; /* Readers need smp_mb(). */ 785 } b; /* Bits. */ 786 u32 s; /* Set of bits. */ 787 }; 788 789 enum perf_event_task_context { 790 perf_invalid_context = -1, 791 perf_hw_context = 0, 792 perf_sw_context, 793 perf_nr_task_contexts, 794 }; 795 796 /* 797 * Number of contexts where an event can trigger: 798 * task, softirq, hardirq, nmi. 799 */ 800 #define PERF_NR_CONTEXTS 4 801 802 struct wake_q_node { 803 struct wake_q_node *next; 804 }; 805 806 struct kmap_ctrl { 807 #ifdef CONFIG_KMAP_LOCAL 808 int idx; 809 pte_t pteval[KM_MAX_IDX]; 810 #endif 811 }; 812 813 struct task_struct { 814 #ifdef CONFIG_THREAD_INFO_IN_TASK 815 /* 816 * For reasons of header soup (see current_thread_info()), this 817 * must be the first element of task_struct. 818 */ 819 struct thread_info thread_info; 820 #endif 821 unsigned int __state; 822 823 /* saved state for "spinlock sleepers" */ 824 unsigned int saved_state; 825 826 /* 827 * This begins the randomizable portion of task_struct. Only 828 * scheduling-critical items should be added above here. 829 */ 830 randomized_struct_fields_start 831 832 void *stack; 833 refcount_t usage; 834 /* Per task flags (PF_*), defined further below: */ 835 unsigned int flags; 836 unsigned int ptrace; 837 838 #ifdef CONFIG_MEM_ALLOC_PROFILING 839 struct alloc_tag *alloc_tag; 840 #endif 841 842 #ifdef CONFIG_SMP 843 int on_cpu; 844 struct __call_single_node wake_entry; 845 unsigned int wakee_flips; 846 unsigned long wakee_flip_decay_ts; 847 struct task_struct *last_wakee; 848 849 /* 850 * recent_used_cpu is initially set as the last CPU used by a task 851 * that wakes affine another task. Waker/wakee relationships can 852 * push tasks around a CPU where each wakeup moves to the next one. 853 * Tracking a recently used CPU allows a quick search for a recently 854 * used CPU that may be idle. 855 */ 856 int recent_used_cpu; 857 int wake_cpu; 858 #endif 859 int on_rq; 860 861 int prio; 862 int static_prio; 863 int normal_prio; 864 unsigned int rt_priority; 865 866 struct sched_entity se; 867 struct sched_rt_entity rt; 868 struct sched_dl_entity dl; 869 struct sched_dl_entity *dl_server; 870 #ifdef CONFIG_SCHED_CLASS_EXT 871 struct sched_ext_entity scx; 872 #endif 873 const struct sched_class *sched_class; 874 875 #ifdef CONFIG_SCHED_CORE 876 struct rb_node core_node; 877 unsigned long core_cookie; 878 unsigned int core_occupation; 879 #endif 880 881 #ifdef CONFIG_CGROUP_SCHED 882 struct task_group *sched_task_group; 883 #endif 884 885 886 #ifdef CONFIG_UCLAMP_TASK 887 /* 888 * Clamp values requested for a scheduling entity. 889 * Must be updated with task_rq_lock() held. 890 */ 891 struct uclamp_se uclamp_req[UCLAMP_CNT]; 892 /* 893 * Effective clamp values used for a scheduling entity. 894 * Must be updated with task_rq_lock() held. 895 */ 896 struct uclamp_se uclamp[UCLAMP_CNT]; 897 #endif 898 899 struct sched_statistics stats; 900 901 #ifdef CONFIG_PREEMPT_NOTIFIERS 902 /* List of struct preempt_notifier: */ 903 struct hlist_head preempt_notifiers; 904 #endif 905 906 #ifdef CONFIG_BLK_DEV_IO_TRACE 907 unsigned int btrace_seq; 908 #endif 909 910 unsigned int policy; 911 unsigned long max_allowed_capacity; 912 int nr_cpus_allowed; 913 const cpumask_t *cpus_ptr; 914 cpumask_t *user_cpus_ptr; 915 cpumask_t cpus_mask; 916 void *migration_pending; 917 #ifdef CONFIG_SMP 918 unsigned short migration_disabled; 919 #endif 920 unsigned short migration_flags; 921 922 #ifdef CONFIG_PREEMPT_RCU 923 int rcu_read_lock_nesting; 924 union rcu_special rcu_read_unlock_special; 925 struct list_head rcu_node_entry; 926 struct rcu_node *rcu_blocked_node; 927 #endif /* #ifdef CONFIG_PREEMPT_RCU */ 928 929 #ifdef CONFIG_TASKS_RCU 930 unsigned long rcu_tasks_nvcsw; 931 u8 rcu_tasks_holdout; 932 u8 rcu_tasks_idx; 933 int rcu_tasks_idle_cpu; 934 struct list_head rcu_tasks_holdout_list; 935 int rcu_tasks_exit_cpu; 936 struct list_head rcu_tasks_exit_list; 937 #endif /* #ifdef CONFIG_TASKS_RCU */ 938 939 #ifdef CONFIG_TASKS_TRACE_RCU 940 int trc_reader_nesting; 941 int trc_ipi_to_cpu; 942 union rcu_special trc_reader_special; 943 struct list_head trc_holdout_list; 944 struct list_head trc_blkd_node; 945 int trc_blkd_cpu; 946 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */ 947 948 struct sched_info sched_info; 949 950 struct list_head tasks; 951 #ifdef CONFIG_SMP 952 struct plist_node pushable_tasks; 953 struct rb_node pushable_dl_tasks; 954 #endif 955 956 struct mm_struct *mm; 957 struct mm_struct *active_mm; 958 struct address_space *faults_disabled_mapping; 959 960 int exit_state; 961 int exit_code; 962 int exit_signal; 963 /* The signal sent when the parent dies: */ 964 int pdeath_signal; 965 /* JOBCTL_*, siglock protected: */ 966 unsigned long jobctl; 967 968 /* Used for emulating ABI behavior of previous Linux versions: */ 969 unsigned int personality; 970 971 /* Scheduler bits, serialized by scheduler locks: */ 972 unsigned sched_reset_on_fork:1; 973 unsigned sched_contributes_to_load:1; 974 unsigned sched_migrated:1; 975 unsigned sched_task_hot:1; 976 977 /* Force alignment to the next boundary: */ 978 unsigned :0; 979 980 /* Unserialized, strictly 'current' */ 981 982 /* 983 * This field must not be in the scheduler word above due to wakelist 984 * queueing no longer being serialized by p->on_cpu. However: 985 * 986 * p->XXX = X; ttwu() 987 * schedule() if (p->on_rq && ..) // false 988 * smp_mb__after_spinlock(); if (smp_load_acquire(&p->on_cpu) && //true 989 * deactivate_task() ttwu_queue_wakelist()) 990 * p->on_rq = 0; p->sched_remote_wakeup = Y; 991 * 992 * guarantees all stores of 'current' are visible before 993 * ->sched_remote_wakeup gets used, so it can be in this word. 994 */ 995 unsigned sched_remote_wakeup:1; 996 #ifdef CONFIG_RT_MUTEXES 997 unsigned sched_rt_mutex:1; 998 #endif 999 1000 /* Bit to tell TOMOYO we're in execve(): */ 1001 unsigned in_execve:1; 1002 unsigned in_iowait:1; 1003 #ifndef TIF_RESTORE_SIGMASK 1004 unsigned restore_sigmask:1; 1005 #endif 1006 #ifdef CONFIG_MEMCG_V1 1007 unsigned in_user_fault:1; 1008 #endif 1009 #ifdef CONFIG_LRU_GEN 1010 /* whether the LRU algorithm may apply to this access */ 1011 unsigned in_lru_fault:1; 1012 #endif 1013 #ifdef CONFIG_COMPAT_BRK 1014 unsigned brk_randomized:1; 1015 #endif 1016 #ifdef CONFIG_CGROUPS 1017 /* disallow userland-initiated cgroup migration */ 1018 unsigned no_cgroup_migration:1; 1019 /* task is frozen/stopped (used by the cgroup freezer) */ 1020 unsigned frozen:1; 1021 #endif 1022 #ifdef CONFIG_BLK_CGROUP 1023 unsigned use_memdelay:1; 1024 #endif 1025 #ifdef CONFIG_PSI 1026 /* Stalled due to lack of memory */ 1027 unsigned in_memstall:1; 1028 #endif 1029 #ifdef CONFIG_PAGE_OWNER 1030 /* Used by page_owner=on to detect recursion in page tracking. */ 1031 unsigned in_page_owner:1; 1032 #endif 1033 #ifdef CONFIG_EVENTFD 1034 /* Recursion prevention for eventfd_signal() */ 1035 unsigned in_eventfd:1; 1036 #endif 1037 #ifdef CONFIG_ARCH_HAS_CPU_PASID 1038 unsigned pasid_activated:1; 1039 #endif 1040 #ifdef CONFIG_X86_BUS_LOCK_DETECT 1041 unsigned reported_split_lock:1; 1042 #endif 1043 #ifdef CONFIG_TASK_DELAY_ACCT 1044 /* delay due to memory thrashing */ 1045 unsigned in_thrashing:1; 1046 #endif 1047 #ifdef CONFIG_PREEMPT_RT 1048 struct netdev_xmit net_xmit; 1049 #endif 1050 unsigned long atomic_flags; /* Flags requiring atomic access. */ 1051 1052 struct restart_block restart_block; 1053 1054 pid_t pid; 1055 pid_t tgid; 1056 1057 #ifdef CONFIG_STACKPROTECTOR 1058 /* Canary value for the -fstack-protector GCC feature: */ 1059 unsigned long stack_canary; 1060 #endif 1061 /* 1062 * Pointers to the (original) parent process, youngest child, younger sibling, 1063 * older sibling, respectively. (p->father can be replaced with 1064 * p->real_parent->pid) 1065 */ 1066 1067 /* Real parent process: */ 1068 struct task_struct __rcu *real_parent; 1069 1070 /* Recipient of SIGCHLD, wait4() reports: */ 1071 struct task_struct __rcu *parent; 1072 1073 /* 1074 * Children/sibling form the list of natural children: 1075 */ 1076 struct list_head children; 1077 struct list_head sibling; 1078 struct task_struct *group_leader; 1079 1080 /* 1081 * 'ptraced' is the list of tasks this task is using ptrace() on. 1082 * 1083 * This includes both natural children and PTRACE_ATTACH targets. 1084 * 'ptrace_entry' is this task's link on the p->parent->ptraced list. 1085 */ 1086 struct list_head ptraced; 1087 struct list_head ptrace_entry; 1088 1089 /* PID/PID hash table linkage. */ 1090 struct pid *thread_pid; 1091 struct hlist_node pid_links[PIDTYPE_MAX]; 1092 struct list_head thread_node; 1093 1094 struct completion *vfork_done; 1095 1096 /* CLONE_CHILD_SETTID: */ 1097 int __user *set_child_tid; 1098 1099 /* CLONE_CHILD_CLEARTID: */ 1100 int __user *clear_child_tid; 1101 1102 /* PF_KTHREAD | PF_IO_WORKER */ 1103 void *worker_private; 1104 1105 u64 utime; 1106 u64 stime; 1107 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME 1108 u64 utimescaled; 1109 u64 stimescaled; 1110 #endif 1111 u64 gtime; 1112 struct prev_cputime prev_cputime; 1113 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN 1114 struct vtime vtime; 1115 #endif 1116 1117 #ifdef CONFIG_NO_HZ_FULL 1118 atomic_t tick_dep_mask; 1119 #endif 1120 /* Context switch counts: */ 1121 unsigned long nvcsw; 1122 unsigned long nivcsw; 1123 1124 /* Monotonic time in nsecs: */ 1125 u64 start_time; 1126 1127 /* Boot based time in nsecs: */ 1128 u64 start_boottime; 1129 1130 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */ 1131 unsigned long min_flt; 1132 unsigned long maj_flt; 1133 1134 /* Empty if CONFIG_POSIX_CPUTIMERS=n */ 1135 struct posix_cputimers posix_cputimers; 1136 1137 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK 1138 struct posix_cputimers_work posix_cputimers_work; 1139 #endif 1140 1141 /* Process credentials: */ 1142 1143 /* Tracer's credentials at attach: */ 1144 const struct cred __rcu *ptracer_cred; 1145 1146 /* Objective and real subjective task credentials (COW): */ 1147 const struct cred __rcu *real_cred; 1148 1149 /* Effective (overridable) subjective task credentials (COW): */ 1150 const struct cred __rcu *cred; 1151 1152 #ifdef CONFIG_KEYS 1153 /* Cached requested key. */ 1154 struct key *cached_requested_key; 1155 #endif 1156 1157 /* 1158 * executable name, excluding path. 1159 * 1160 * - normally initialized begin_new_exec() 1161 * - set it with set_task_comm() 1162 * - strscpy_pad() to ensure it is always NUL-terminated and 1163 * zero-padded 1164 * - task_lock() to ensure the operation is atomic and the name is 1165 * fully updated. 1166 */ 1167 char comm[TASK_COMM_LEN]; 1168 1169 struct nameidata *nameidata; 1170 1171 #ifdef CONFIG_SYSVIPC 1172 struct sysv_sem sysvsem; 1173 struct sysv_shm sysvshm; 1174 #endif 1175 #ifdef CONFIG_DETECT_HUNG_TASK 1176 unsigned long last_switch_count; 1177 unsigned long last_switch_time; 1178 #endif 1179 /* Filesystem information: */ 1180 struct fs_struct *fs; 1181 1182 /* Open file information: */ 1183 struct files_struct *files; 1184 1185 #ifdef CONFIG_IO_URING 1186 struct io_uring_task *io_uring; 1187 #endif 1188 1189 /* Namespaces: */ 1190 struct nsproxy *nsproxy; 1191 1192 /* Signal handlers: */ 1193 struct signal_struct *signal; 1194 struct sighand_struct __rcu *sighand; 1195 sigset_t blocked; 1196 sigset_t real_blocked; 1197 /* Restored if set_restore_sigmask() was used: */ 1198 sigset_t saved_sigmask; 1199 struct sigpending pending; 1200 unsigned long sas_ss_sp; 1201 size_t sas_ss_size; 1202 unsigned int sas_ss_flags; 1203 1204 struct callback_head *task_works; 1205 1206 #ifdef CONFIG_AUDIT 1207 #ifdef CONFIG_AUDITSYSCALL 1208 struct audit_context *audit_context; 1209 #endif 1210 kuid_t loginuid; 1211 unsigned int sessionid; 1212 #endif 1213 struct seccomp seccomp; 1214 struct syscall_user_dispatch syscall_dispatch; 1215 1216 /* Thread group tracking: */ 1217 u64 parent_exec_id; 1218 u64 self_exec_id; 1219 1220 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */ 1221 spinlock_t alloc_lock; 1222 1223 /* Protection of the PI data structures: */ 1224 raw_spinlock_t pi_lock; 1225 1226 struct wake_q_node wake_q; 1227 1228 #ifdef CONFIG_RT_MUTEXES 1229 /* PI waiters blocked on a rt_mutex held by this task: */ 1230 struct rb_root_cached pi_waiters; 1231 /* Updated under owner's pi_lock and rq lock */ 1232 struct task_struct *pi_top_task; 1233 /* Deadlock detection and priority inheritance handling: */ 1234 struct rt_mutex_waiter *pi_blocked_on; 1235 #endif 1236 1237 #ifdef CONFIG_DEBUG_MUTEXES 1238 /* Mutex deadlock detection: */ 1239 struct mutex_waiter *blocked_on; 1240 #endif 1241 1242 #ifdef CONFIG_DETECT_HUNG_TASK_BLOCKER 1243 struct mutex *blocker_mutex; 1244 #endif 1245 1246 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1247 int non_block_count; 1248 #endif 1249 1250 #ifdef CONFIG_TRACE_IRQFLAGS 1251 struct irqtrace_events irqtrace; 1252 unsigned int hardirq_threaded; 1253 u64 hardirq_chain_key; 1254 int softirqs_enabled; 1255 int softirq_context; 1256 int irq_config; 1257 #endif 1258 #ifdef CONFIG_PREEMPT_RT 1259 int softirq_disable_cnt; 1260 #endif 1261 1262 #ifdef CONFIG_LOCKDEP 1263 # define MAX_LOCK_DEPTH 48UL 1264 u64 curr_chain_key; 1265 int lockdep_depth; 1266 unsigned int lockdep_recursion; 1267 struct held_lock held_locks[MAX_LOCK_DEPTH]; 1268 #endif 1269 1270 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP) 1271 unsigned int in_ubsan; 1272 #endif 1273 1274 /* Journalling filesystem info: */ 1275 void *journal_info; 1276 1277 /* Stacked block device info: */ 1278 struct bio_list *bio_list; 1279 1280 /* Stack plugging: */ 1281 struct blk_plug *plug; 1282 1283 /* VM state: */ 1284 struct reclaim_state *reclaim_state; 1285 1286 struct io_context *io_context; 1287 1288 #ifdef CONFIG_COMPACTION 1289 struct capture_control *capture_control; 1290 #endif 1291 /* Ptrace state: */ 1292 unsigned long ptrace_message; 1293 kernel_siginfo_t *last_siginfo; 1294 1295 struct task_io_accounting ioac; 1296 #ifdef CONFIG_PSI 1297 /* Pressure stall state */ 1298 unsigned int psi_flags; 1299 #endif 1300 #ifdef CONFIG_TASK_XACCT 1301 /* Accumulated RSS usage: */ 1302 u64 acct_rss_mem1; 1303 /* Accumulated virtual memory usage: */ 1304 u64 acct_vm_mem1; 1305 /* stime + utime since last update: */ 1306 u64 acct_timexpd; 1307 #endif 1308 #ifdef CONFIG_CPUSETS 1309 /* Protected by ->alloc_lock: */ 1310 nodemask_t mems_allowed; 1311 /* Sequence number to catch updates: */ 1312 seqcount_spinlock_t mems_allowed_seq; 1313 int cpuset_mem_spread_rotor; 1314 #endif 1315 #ifdef CONFIG_CGROUPS 1316 /* Control Group info protected by css_set_lock: */ 1317 struct css_set __rcu *cgroups; 1318 /* cg_list protected by css_set_lock and tsk->alloc_lock: */ 1319 struct list_head cg_list; 1320 #endif 1321 #ifdef CONFIG_X86_CPU_RESCTRL 1322 u32 closid; 1323 u32 rmid; 1324 #endif 1325 #ifdef CONFIG_FUTEX 1326 struct robust_list_head __user *robust_list; 1327 #ifdef CONFIG_COMPAT 1328 struct compat_robust_list_head __user *compat_robust_list; 1329 #endif 1330 struct list_head pi_state_list; 1331 struct futex_pi_state *pi_state_cache; 1332 struct mutex futex_exit_mutex; 1333 unsigned int futex_state; 1334 #endif 1335 #ifdef CONFIG_PERF_EVENTS 1336 u8 perf_recursion[PERF_NR_CONTEXTS]; 1337 struct perf_event_context *perf_event_ctxp; 1338 struct mutex perf_event_mutex; 1339 struct list_head perf_event_list; 1340 struct perf_ctx_data __rcu *perf_ctx_data; 1341 #endif 1342 #ifdef CONFIG_DEBUG_PREEMPT 1343 unsigned long preempt_disable_ip; 1344 #endif 1345 #ifdef CONFIG_NUMA 1346 /* Protected by alloc_lock: */ 1347 struct mempolicy *mempolicy; 1348 short il_prev; 1349 u8 il_weight; 1350 short pref_node_fork; 1351 #endif 1352 #ifdef CONFIG_NUMA_BALANCING 1353 int numa_scan_seq; 1354 unsigned int numa_scan_period; 1355 unsigned int numa_scan_period_max; 1356 int numa_preferred_nid; 1357 unsigned long numa_migrate_retry; 1358 /* Migration stamp: */ 1359 u64 node_stamp; 1360 u64 last_task_numa_placement; 1361 u64 last_sum_exec_runtime; 1362 struct callback_head numa_work; 1363 1364 /* 1365 * This pointer is only modified for current in syscall and 1366 * pagefault context (and for tasks being destroyed), so it can be read 1367 * from any of the following contexts: 1368 * - RCU read-side critical section 1369 * - current->numa_group from everywhere 1370 * - task's runqueue locked, task not running 1371 */ 1372 struct numa_group __rcu *numa_group; 1373 1374 /* 1375 * numa_faults is an array split into four regions: 1376 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer 1377 * in this precise order. 1378 * 1379 * faults_memory: Exponential decaying average of faults on a per-node 1380 * basis. Scheduling placement decisions are made based on these 1381 * counts. The values remain static for the duration of a PTE scan. 1382 * faults_cpu: Track the nodes the process was running on when a NUMA 1383 * hinting fault was incurred. 1384 * faults_memory_buffer and faults_cpu_buffer: Record faults per node 1385 * during the current scan window. When the scan completes, the counts 1386 * in faults_memory and faults_cpu decay and these values are copied. 1387 */ 1388 unsigned long *numa_faults; 1389 unsigned long total_numa_faults; 1390 1391 /* 1392 * numa_faults_locality tracks if faults recorded during the last 1393 * scan window were remote/local or failed to migrate. The task scan 1394 * period is adapted based on the locality of the faults with different 1395 * weights depending on whether they were shared or private faults 1396 */ 1397 unsigned long numa_faults_locality[3]; 1398 1399 unsigned long numa_pages_migrated; 1400 #endif /* CONFIG_NUMA_BALANCING */ 1401 1402 #ifdef CONFIG_RSEQ 1403 struct rseq __user *rseq; 1404 u32 rseq_len; 1405 u32 rseq_sig; 1406 /* 1407 * RmW on rseq_event_mask must be performed atomically 1408 * with respect to preemption. 1409 */ 1410 unsigned long rseq_event_mask; 1411 # ifdef CONFIG_DEBUG_RSEQ 1412 /* 1413 * This is a place holder to save a copy of the rseq fields for 1414 * validation of read-only fields. The struct rseq has a 1415 * variable-length array at the end, so it cannot be used 1416 * directly. Reserve a size large enough for the known fields. 1417 */ 1418 char rseq_fields[sizeof(struct rseq)]; 1419 # endif 1420 #endif 1421 1422 #ifdef CONFIG_SCHED_MM_CID 1423 int mm_cid; /* Current cid in mm */ 1424 int last_mm_cid; /* Most recent cid in mm */ 1425 int migrate_from_cpu; 1426 int mm_cid_active; /* Whether cid bitmap is active */ 1427 struct callback_head cid_work; 1428 #endif 1429 1430 struct tlbflush_unmap_batch tlb_ubc; 1431 1432 /* Cache last used pipe for splice(): */ 1433 struct pipe_inode_info *splice_pipe; 1434 1435 struct page_frag task_frag; 1436 1437 #ifdef CONFIG_TASK_DELAY_ACCT 1438 struct task_delay_info *delays; 1439 #endif 1440 1441 #ifdef CONFIG_FAULT_INJECTION 1442 int make_it_fail; 1443 unsigned int fail_nth; 1444 #endif 1445 /* 1446 * When (nr_dirtied >= nr_dirtied_pause), it's time to call 1447 * balance_dirty_pages() for a dirty throttling pause: 1448 */ 1449 int nr_dirtied; 1450 int nr_dirtied_pause; 1451 /* Start of a write-and-pause period: */ 1452 unsigned long dirty_paused_when; 1453 1454 #ifdef CONFIG_LATENCYTOP 1455 int latency_record_count; 1456 struct latency_record latency_record[LT_SAVECOUNT]; 1457 #endif 1458 /* 1459 * Time slack values; these are used to round up poll() and 1460 * select() etc timeout values. These are in nanoseconds. 1461 */ 1462 u64 timer_slack_ns; 1463 u64 default_timer_slack_ns; 1464 1465 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) 1466 unsigned int kasan_depth; 1467 #endif 1468 1469 #ifdef CONFIG_KCSAN 1470 struct kcsan_ctx kcsan_ctx; 1471 #ifdef CONFIG_TRACE_IRQFLAGS 1472 struct irqtrace_events kcsan_save_irqtrace; 1473 #endif 1474 #ifdef CONFIG_KCSAN_WEAK_MEMORY 1475 int kcsan_stack_depth; 1476 #endif 1477 #endif 1478 1479 #ifdef CONFIG_KMSAN 1480 struct kmsan_ctx kmsan_ctx; 1481 #endif 1482 1483 #if IS_ENABLED(CONFIG_KUNIT) 1484 struct kunit *kunit_test; 1485 #endif 1486 1487 #ifdef CONFIG_FUNCTION_GRAPH_TRACER 1488 /* Index of current stored address in ret_stack: */ 1489 int curr_ret_stack; 1490 int curr_ret_depth; 1491 1492 /* Stack of return addresses for return function tracing: */ 1493 unsigned long *ret_stack; 1494 1495 /* Timestamp for last schedule: */ 1496 unsigned long long ftrace_timestamp; 1497 unsigned long long ftrace_sleeptime; 1498 1499 /* 1500 * Number of functions that haven't been traced 1501 * because of depth overrun: 1502 */ 1503 atomic_t trace_overrun; 1504 1505 /* Pause tracing: */ 1506 atomic_t tracing_graph_pause; 1507 #endif 1508 1509 #ifdef CONFIG_TRACING 1510 /* Bitmask and counter of trace recursion: */ 1511 unsigned long trace_recursion; 1512 #endif /* CONFIG_TRACING */ 1513 1514 #ifdef CONFIG_KCOV 1515 /* See kernel/kcov.c for more details. */ 1516 1517 /* Coverage collection mode enabled for this task (0 if disabled): */ 1518 unsigned int kcov_mode; 1519 1520 /* Size of the kcov_area: */ 1521 unsigned int kcov_size; 1522 1523 /* Buffer for coverage collection: */ 1524 void *kcov_area; 1525 1526 /* KCOV descriptor wired with this task or NULL: */ 1527 struct kcov *kcov; 1528 1529 /* KCOV common handle for remote coverage collection: */ 1530 u64 kcov_handle; 1531 1532 /* KCOV sequence number: */ 1533 int kcov_sequence; 1534 1535 /* Collect coverage from softirq context: */ 1536 unsigned int kcov_softirq; 1537 #endif 1538 1539 #ifdef CONFIG_MEMCG_V1 1540 struct mem_cgroup *memcg_in_oom; 1541 #endif 1542 1543 #ifdef CONFIG_MEMCG 1544 /* Number of pages to reclaim on returning to userland: */ 1545 unsigned int memcg_nr_pages_over_high; 1546 1547 /* Used by memcontrol for targeted memcg charge: */ 1548 struct mem_cgroup *active_memcg; 1549 1550 /* Cache for current->cgroups->memcg->objcg lookups: */ 1551 struct obj_cgroup *objcg; 1552 #endif 1553 1554 #ifdef CONFIG_BLK_CGROUP 1555 struct gendisk *throttle_disk; 1556 #endif 1557 1558 #ifdef CONFIG_UPROBES 1559 struct uprobe_task *utask; 1560 #endif 1561 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE) 1562 unsigned int sequential_io; 1563 unsigned int sequential_io_avg; 1564 #endif 1565 struct kmap_ctrl kmap_ctrl; 1566 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 1567 unsigned long task_state_change; 1568 # ifdef CONFIG_PREEMPT_RT 1569 unsigned long saved_state_change; 1570 # endif 1571 #endif 1572 struct rcu_head rcu; 1573 refcount_t rcu_users; 1574 int pagefault_disabled; 1575 #ifdef CONFIG_MMU 1576 struct task_struct *oom_reaper_list; 1577 struct timer_list oom_reaper_timer; 1578 #endif 1579 #ifdef CONFIG_VMAP_STACK 1580 struct vm_struct *stack_vm_area; 1581 #endif 1582 #ifdef CONFIG_THREAD_INFO_IN_TASK 1583 /* A live task holds one reference: */ 1584 refcount_t stack_refcount; 1585 #endif 1586 #ifdef CONFIG_LIVEPATCH 1587 int patch_state; 1588 #endif 1589 #ifdef CONFIG_SECURITY 1590 /* Used by LSM modules for access restriction: */ 1591 void *security; 1592 #endif 1593 #ifdef CONFIG_BPF_SYSCALL 1594 /* Used by BPF task local storage */ 1595 struct bpf_local_storage __rcu *bpf_storage; 1596 /* Used for BPF run context */ 1597 struct bpf_run_ctx *bpf_ctx; 1598 #endif 1599 /* Used by BPF for per-TASK xdp storage */ 1600 struct bpf_net_context *bpf_net_context; 1601 1602 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK 1603 unsigned long lowest_stack; 1604 unsigned long prev_lowest_stack; 1605 #endif 1606 1607 #ifdef CONFIG_X86_MCE 1608 void __user *mce_vaddr; 1609 __u64 mce_kflags; 1610 u64 mce_addr; 1611 __u64 mce_ripv : 1, 1612 mce_whole_page : 1, 1613 __mce_reserved : 62; 1614 struct callback_head mce_kill_me; 1615 int mce_count; 1616 #endif 1617 1618 #ifdef CONFIG_KRETPROBES 1619 struct llist_head kretprobe_instances; 1620 #endif 1621 #ifdef CONFIG_RETHOOK 1622 struct llist_head rethooks; 1623 #endif 1624 1625 #ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH 1626 /* 1627 * If L1D flush is supported on mm context switch 1628 * then we use this callback head to queue kill work 1629 * to kill tasks that are not running on SMT disabled 1630 * cores 1631 */ 1632 struct callback_head l1d_flush_kill; 1633 #endif 1634 1635 #ifdef CONFIG_RV 1636 /* 1637 * Per-task RV monitor. Nowadays fixed in RV_PER_TASK_MONITORS. 1638 * If we find justification for more monitors, we can think 1639 * about adding more or developing a dynamic method. So far, 1640 * none of these are justified. 1641 */ 1642 union rv_task_monitor rv[RV_PER_TASK_MONITORS]; 1643 #endif 1644 1645 #ifdef CONFIG_USER_EVENTS 1646 struct user_event_mm *user_event_mm; 1647 #endif 1648 1649 /* 1650 * New fields for task_struct should be added above here, so that 1651 * they are included in the randomized portion of task_struct. 1652 */ 1653 randomized_struct_fields_end 1654 1655 /* CPU-specific state of this task: */ 1656 struct thread_struct thread; 1657 1658 /* 1659 * WARNING: on x86, 'thread_struct' contains a variable-sized 1660 * structure. It *MUST* be at the end of 'task_struct'. 1661 * 1662 * Do not put anything below here! 1663 */ 1664 }; 1665 1666 #define TASK_REPORT_IDLE (TASK_REPORT + 1) 1667 #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1) 1668 1669 static inline unsigned int __task_state_index(unsigned int tsk_state, 1670 unsigned int tsk_exit_state) 1671 { 1672 unsigned int state = (tsk_state | tsk_exit_state) & TASK_REPORT; 1673 1674 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX); 1675 1676 if ((tsk_state & TASK_IDLE) == TASK_IDLE) 1677 state = TASK_REPORT_IDLE; 1678 1679 /* 1680 * We're lying here, but rather than expose a completely new task state 1681 * to userspace, we can make this appear as if the task has gone through 1682 * a regular rt_mutex_lock() call. 1683 * Report frozen tasks as uninterruptible. 1684 */ 1685 if ((tsk_state & TASK_RTLOCK_WAIT) || (tsk_state & TASK_FROZEN)) 1686 state = TASK_UNINTERRUPTIBLE; 1687 1688 return fls(state); 1689 } 1690 1691 static inline unsigned int task_state_index(struct task_struct *tsk) 1692 { 1693 return __task_state_index(READ_ONCE(tsk->__state), tsk->exit_state); 1694 } 1695 1696 static inline char task_index_to_char(unsigned int state) 1697 { 1698 static const char state_char[] = "RSDTtXZPI"; 1699 1700 BUILD_BUG_ON(TASK_REPORT_MAX * 2 != 1 << (sizeof(state_char) - 1)); 1701 1702 return state_char[state]; 1703 } 1704 1705 static inline char task_state_to_char(struct task_struct *tsk) 1706 { 1707 return task_index_to_char(task_state_index(tsk)); 1708 } 1709 1710 extern struct pid *cad_pid; 1711 1712 /* 1713 * Per process flags 1714 */ 1715 #define PF_VCPU 0x00000001 /* I'm a virtual CPU */ 1716 #define PF_IDLE 0x00000002 /* I am an IDLE thread */ 1717 #define PF_EXITING 0x00000004 /* Getting shut down */ 1718 #define PF_POSTCOREDUMP 0x00000008 /* Coredumps should ignore this task */ 1719 #define PF_IO_WORKER 0x00000010 /* Task is an IO worker */ 1720 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */ 1721 #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */ 1722 #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */ 1723 #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */ 1724 #define PF_DUMPCORE 0x00000200 /* Dumped core */ 1725 #define PF_SIGNALED 0x00000400 /* Killed by a signal */ 1726 #define PF_MEMALLOC 0x00000800 /* Allocating memory to free memory. See memalloc_noreclaim_save() */ 1727 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */ 1728 #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */ 1729 #define PF_USER_WORKER 0x00004000 /* Kernel thread cloned from userspace thread */ 1730 #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */ 1731 #define PF_KCOMPACTD 0x00010000 /* I am kcompactd */ 1732 #define PF_KSWAPD 0x00020000 /* I am kswapd */ 1733 #define PF_MEMALLOC_NOFS 0x00040000 /* All allocations inherit GFP_NOFS. See memalloc_nfs_save() */ 1734 #define PF_MEMALLOC_NOIO 0x00080000 /* All allocations inherit GFP_NOIO. See memalloc_noio_save() */ 1735 #define PF_LOCAL_THROTTLE 0x00100000 /* Throttle writes only against the bdi I write to, 1736 * I am cleaning dirty pages from some other bdi. */ 1737 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ 1738 #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */ 1739 #define PF__HOLE__00800000 0x00800000 1740 #define PF__HOLE__01000000 0x01000000 1741 #define PF__HOLE__02000000 0x02000000 1742 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */ 1743 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ 1744 #define PF_MEMALLOC_PIN 0x10000000 /* Allocations constrained to zones which allow long term pinning. 1745 * See memalloc_pin_save() */ 1746 #define PF_BLOCK_TS 0x20000000 /* plug has ts that needs updating */ 1747 #define PF__HOLE__40000000 0x40000000 1748 #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */ 1749 1750 /* 1751 * Only the _current_ task can read/write to tsk->flags, but other 1752 * tasks can access tsk->flags in readonly mode for example 1753 * with tsk_used_math (like during threaded core dumping). 1754 * There is however an exception to this rule during ptrace 1755 * or during fork: the ptracer task is allowed to write to the 1756 * child->flags of its traced child (same goes for fork, the parent 1757 * can write to the child->flags), because we're guaranteed the 1758 * child is not running and in turn not changing child->flags 1759 * at the same time the parent does it. 1760 */ 1761 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0) 1762 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0) 1763 #define clear_used_math() clear_stopped_child_used_math(current) 1764 #define set_used_math() set_stopped_child_used_math(current) 1765 1766 #define conditional_stopped_child_used_math(condition, child) \ 1767 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0) 1768 1769 #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current) 1770 1771 #define copy_to_stopped_child_used_math(child) \ 1772 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0) 1773 1774 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */ 1775 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH) 1776 #define used_math() tsk_used_math(current) 1777 1778 static __always_inline bool is_percpu_thread(void) 1779 { 1780 #ifdef CONFIG_SMP 1781 return (current->flags & PF_NO_SETAFFINITY) && 1782 (current->nr_cpus_allowed == 1); 1783 #else 1784 return true; 1785 #endif 1786 } 1787 1788 /* Per-process atomic flags. */ 1789 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */ 1790 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */ 1791 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */ 1792 #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */ 1793 #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/ 1794 #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */ 1795 #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */ 1796 #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */ 1797 1798 #define TASK_PFA_TEST(name, func) \ 1799 static inline bool task_##func(struct task_struct *p) \ 1800 { return test_bit(PFA_##name, &p->atomic_flags); } 1801 1802 #define TASK_PFA_SET(name, func) \ 1803 static inline void task_set_##func(struct task_struct *p) \ 1804 { set_bit(PFA_##name, &p->atomic_flags); } 1805 1806 #define TASK_PFA_CLEAR(name, func) \ 1807 static inline void task_clear_##func(struct task_struct *p) \ 1808 { clear_bit(PFA_##name, &p->atomic_flags); } 1809 1810 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs) 1811 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs) 1812 1813 TASK_PFA_TEST(SPREAD_PAGE, spread_page) 1814 TASK_PFA_SET(SPREAD_PAGE, spread_page) 1815 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page) 1816 1817 TASK_PFA_TEST(SPREAD_SLAB, spread_slab) 1818 TASK_PFA_SET(SPREAD_SLAB, spread_slab) 1819 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab) 1820 1821 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable) 1822 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable) 1823 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable) 1824 1825 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1826 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1827 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec) 1828 1829 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1830 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable) 1831 1832 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable) 1833 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable) 1834 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable) 1835 1836 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1837 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable) 1838 1839 static inline void 1840 current_restore_flags(unsigned long orig_flags, unsigned long flags) 1841 { 1842 current->flags &= ~flags; 1843 current->flags |= orig_flags & flags; 1844 } 1845 1846 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial); 1847 extern int task_can_attach(struct task_struct *p); 1848 extern int dl_bw_alloc(int cpu, u64 dl_bw); 1849 extern void dl_bw_free(int cpu, u64 dl_bw); 1850 #ifdef CONFIG_SMP 1851 1852 /* do_set_cpus_allowed() - consider using set_cpus_allowed_ptr() instead */ 1853 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask); 1854 1855 /** 1856 * set_cpus_allowed_ptr - set CPU affinity mask of a task 1857 * @p: the task 1858 * @new_mask: CPU affinity mask 1859 * 1860 * Return: zero if successful, or a negative error code 1861 */ 1862 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask); 1863 extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node); 1864 extern void release_user_cpus_ptr(struct task_struct *p); 1865 extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask); 1866 extern void force_compatible_cpus_allowed_ptr(struct task_struct *p); 1867 extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p); 1868 #else 1869 static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) 1870 { 1871 } 1872 static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask) 1873 { 1874 /* Opencoded cpumask_test_cpu(0, new_mask) to avoid dependency on cpumask.h */ 1875 if ((*cpumask_bits(new_mask) & 1) == 0) 1876 return -EINVAL; 1877 return 0; 1878 } 1879 static inline int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node) 1880 { 1881 if (src->user_cpus_ptr) 1882 return -EINVAL; 1883 return 0; 1884 } 1885 static inline void release_user_cpus_ptr(struct task_struct *p) 1886 { 1887 WARN_ON(p->user_cpus_ptr); 1888 } 1889 1890 static inline int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask) 1891 { 1892 return 0; 1893 } 1894 #endif 1895 1896 extern int yield_to(struct task_struct *p, bool preempt); 1897 extern void set_user_nice(struct task_struct *p, long nice); 1898 extern int task_prio(const struct task_struct *p); 1899 1900 /** 1901 * task_nice - return the nice value of a given task. 1902 * @p: the task in question. 1903 * 1904 * Return: The nice value [ -20 ... 0 ... 19 ]. 1905 */ 1906 static inline int task_nice(const struct task_struct *p) 1907 { 1908 return PRIO_TO_NICE((p)->static_prio); 1909 } 1910 1911 extern int can_nice(const struct task_struct *p, const int nice); 1912 extern int task_curr(const struct task_struct *p); 1913 extern int idle_cpu(int cpu); 1914 extern int available_idle_cpu(int cpu); 1915 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *); 1916 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *); 1917 extern void sched_set_fifo(struct task_struct *p); 1918 extern void sched_set_fifo_low(struct task_struct *p); 1919 extern void sched_set_normal(struct task_struct *p, int nice); 1920 extern int sched_setattr(struct task_struct *, const struct sched_attr *); 1921 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *); 1922 extern struct task_struct *idle_task(int cpu); 1923 1924 /** 1925 * is_idle_task - is the specified task an idle task? 1926 * @p: the task in question. 1927 * 1928 * Return: 1 if @p is an idle task. 0 otherwise. 1929 */ 1930 static __always_inline bool is_idle_task(const struct task_struct *p) 1931 { 1932 return !!(p->flags & PF_IDLE); 1933 } 1934 1935 extern struct task_struct *curr_task(int cpu); 1936 extern void ia64_set_curr_task(int cpu, struct task_struct *p); 1937 1938 void yield(void); 1939 1940 union thread_union { 1941 struct task_struct task; 1942 #ifndef CONFIG_THREAD_INFO_IN_TASK 1943 struct thread_info thread_info; 1944 #endif 1945 unsigned long stack[THREAD_SIZE/sizeof(long)]; 1946 }; 1947 1948 #ifndef CONFIG_THREAD_INFO_IN_TASK 1949 extern struct thread_info init_thread_info; 1950 #endif 1951 1952 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)]; 1953 1954 #ifdef CONFIG_THREAD_INFO_IN_TASK 1955 # define task_thread_info(task) (&(task)->thread_info) 1956 #else 1957 # define task_thread_info(task) ((struct thread_info *)(task)->stack) 1958 #endif 1959 1960 /* 1961 * find a task by one of its numerical ids 1962 * 1963 * find_task_by_pid_ns(): 1964 * finds a task by its pid in the specified namespace 1965 * find_task_by_vpid(): 1966 * finds a task by its virtual pid 1967 * 1968 * see also find_vpid() etc in include/linux/pid.h 1969 */ 1970 1971 extern struct task_struct *find_task_by_vpid(pid_t nr); 1972 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns); 1973 1974 /* 1975 * find a task by its virtual pid and get the task struct 1976 */ 1977 extern struct task_struct *find_get_task_by_vpid(pid_t nr); 1978 1979 extern int wake_up_state(struct task_struct *tsk, unsigned int state); 1980 extern int wake_up_process(struct task_struct *tsk); 1981 extern void wake_up_new_task(struct task_struct *tsk); 1982 1983 #ifdef CONFIG_SMP 1984 extern void kick_process(struct task_struct *tsk); 1985 #else 1986 static inline void kick_process(struct task_struct *tsk) { } 1987 #endif 1988 1989 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec); 1990 #define set_task_comm(tsk, from) ({ \ 1991 BUILD_BUG_ON(sizeof(from) != TASK_COMM_LEN); \ 1992 __set_task_comm(tsk, from, false); \ 1993 }) 1994 1995 /* 1996 * - Why not use task_lock()? 1997 * User space can randomly change their names anyway, so locking for readers 1998 * doesn't make sense. For writers, locking is probably necessary, as a race 1999 * condition could lead to long-term mixed results. 2000 * The strscpy_pad() in __set_task_comm() can ensure that the task comm is 2001 * always NUL-terminated and zero-padded. Therefore the race condition between 2002 * reader and writer is not an issue. 2003 * 2004 * - BUILD_BUG_ON() can help prevent the buf from being truncated. 2005 * Since the callers don't perform any return value checks, this safeguard is 2006 * necessary. 2007 */ 2008 #define get_task_comm(buf, tsk) ({ \ 2009 BUILD_BUG_ON(sizeof(buf) < TASK_COMM_LEN); \ 2010 strscpy_pad(buf, (tsk)->comm); \ 2011 buf; \ 2012 }) 2013 2014 #ifdef CONFIG_SMP 2015 static __always_inline void scheduler_ipi(void) 2016 { 2017 /* 2018 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting 2019 * TIF_NEED_RESCHED remotely (for the first time) will also send 2020 * this IPI. 2021 */ 2022 preempt_fold_need_resched(); 2023 } 2024 #else 2025 static inline void scheduler_ipi(void) { } 2026 #endif 2027 2028 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state); 2029 2030 /* 2031 * Set thread flags in other task's structures. 2032 * See asm/thread_info.h for TIF_xxxx flags available: 2033 */ 2034 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag) 2035 { 2036 set_ti_thread_flag(task_thread_info(tsk), flag); 2037 } 2038 2039 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2040 { 2041 clear_ti_thread_flag(task_thread_info(tsk), flag); 2042 } 2043 2044 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag, 2045 bool value) 2046 { 2047 update_ti_thread_flag(task_thread_info(tsk), flag, value); 2048 } 2049 2050 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag) 2051 { 2052 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag); 2053 } 2054 2055 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag) 2056 { 2057 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag); 2058 } 2059 2060 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag) 2061 { 2062 return test_ti_thread_flag(task_thread_info(tsk), flag); 2063 } 2064 2065 static inline void set_tsk_need_resched(struct task_struct *tsk) 2066 { 2067 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED); 2068 } 2069 2070 static inline void clear_tsk_need_resched(struct task_struct *tsk) 2071 { 2072 atomic_long_andnot(_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY, 2073 (atomic_long_t *)&task_thread_info(tsk)->flags); 2074 } 2075 2076 static inline int test_tsk_need_resched(struct task_struct *tsk) 2077 { 2078 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); 2079 } 2080 2081 /* 2082 * cond_resched() and cond_resched_lock(): latency reduction via 2083 * explicit rescheduling in places that are safe. The return 2084 * value indicates whether a reschedule was done in fact. 2085 * cond_resched_lock() will drop the spinlock before scheduling, 2086 */ 2087 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC) 2088 extern int __cond_resched(void); 2089 2090 #if defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL) 2091 2092 void sched_dynamic_klp_enable(void); 2093 void sched_dynamic_klp_disable(void); 2094 2095 DECLARE_STATIC_CALL(cond_resched, __cond_resched); 2096 2097 static __always_inline int _cond_resched(void) 2098 { 2099 return static_call_mod(cond_resched)(); 2100 } 2101 2102 #elif defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY) 2103 2104 extern int dynamic_cond_resched(void); 2105 2106 static __always_inline int _cond_resched(void) 2107 { 2108 return dynamic_cond_resched(); 2109 } 2110 2111 #else /* !CONFIG_PREEMPTION */ 2112 2113 static inline int _cond_resched(void) 2114 { 2115 klp_sched_try_switch(); 2116 return __cond_resched(); 2117 } 2118 2119 #endif /* PREEMPT_DYNAMIC && CONFIG_HAVE_PREEMPT_DYNAMIC_CALL */ 2120 2121 #else /* CONFIG_PREEMPTION && !CONFIG_PREEMPT_DYNAMIC */ 2122 2123 static inline int _cond_resched(void) 2124 { 2125 klp_sched_try_switch(); 2126 return 0; 2127 } 2128 2129 #endif /* !CONFIG_PREEMPTION || CONFIG_PREEMPT_DYNAMIC */ 2130 2131 #define cond_resched() ({ \ 2132 __might_resched(__FILE__, __LINE__, 0); \ 2133 _cond_resched(); \ 2134 }) 2135 2136 extern int __cond_resched_lock(spinlock_t *lock); 2137 extern int __cond_resched_rwlock_read(rwlock_t *lock); 2138 extern int __cond_resched_rwlock_write(rwlock_t *lock); 2139 2140 #define MIGHT_RESCHED_RCU_SHIFT 8 2141 #define MIGHT_RESCHED_PREEMPT_MASK ((1U << MIGHT_RESCHED_RCU_SHIFT) - 1) 2142 2143 #ifndef CONFIG_PREEMPT_RT 2144 /* 2145 * Non RT kernels have an elevated preempt count due to the held lock, 2146 * but are not allowed to be inside a RCU read side critical section 2147 */ 2148 # define PREEMPT_LOCK_RESCHED_OFFSETS PREEMPT_LOCK_OFFSET 2149 #else 2150 /* 2151 * spin/rw_lock() on RT implies rcu_read_lock(). The might_sleep() check in 2152 * cond_resched*lock() has to take that into account because it checks for 2153 * preempt_count() and rcu_preempt_depth(). 2154 */ 2155 # define PREEMPT_LOCK_RESCHED_OFFSETS \ 2156 (PREEMPT_LOCK_OFFSET + (1U << MIGHT_RESCHED_RCU_SHIFT)) 2157 #endif 2158 2159 #define cond_resched_lock(lock) ({ \ 2160 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ 2161 __cond_resched_lock(lock); \ 2162 }) 2163 2164 #define cond_resched_rwlock_read(lock) ({ \ 2165 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ 2166 __cond_resched_rwlock_read(lock); \ 2167 }) 2168 2169 #define cond_resched_rwlock_write(lock) ({ \ 2170 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \ 2171 __cond_resched_rwlock_write(lock); \ 2172 }) 2173 2174 static __always_inline bool need_resched(void) 2175 { 2176 return unlikely(tif_need_resched()); 2177 } 2178 2179 /* 2180 * Wrappers for p->thread_info->cpu access. No-op on UP. 2181 */ 2182 #ifdef CONFIG_SMP 2183 2184 static inline unsigned int task_cpu(const struct task_struct *p) 2185 { 2186 return READ_ONCE(task_thread_info(p)->cpu); 2187 } 2188 2189 extern void set_task_cpu(struct task_struct *p, unsigned int cpu); 2190 2191 #else 2192 2193 static inline unsigned int task_cpu(const struct task_struct *p) 2194 { 2195 return 0; 2196 } 2197 2198 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu) 2199 { 2200 } 2201 2202 #endif /* CONFIG_SMP */ 2203 2204 static inline bool task_is_runnable(struct task_struct *p) 2205 { 2206 return p->on_rq && !p->se.sched_delayed; 2207 } 2208 2209 extern bool sched_task_on_rq(struct task_struct *p); 2210 extern unsigned long get_wchan(struct task_struct *p); 2211 extern struct task_struct *cpu_curr_snapshot(int cpu); 2212 2213 #include <linux/spinlock.h> 2214 2215 /* 2216 * In order to reduce various lock holder preemption latencies provide an 2217 * interface to see if a vCPU is currently running or not. 2218 * 2219 * This allows us to terminate optimistic spin loops and block, analogous to 2220 * the native optimistic spin heuristic of testing if the lock owner task is 2221 * running or not. 2222 */ 2223 #ifndef vcpu_is_preempted 2224 static inline bool vcpu_is_preempted(int cpu) 2225 { 2226 return false; 2227 } 2228 #endif 2229 2230 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask); 2231 extern long sched_getaffinity(pid_t pid, struct cpumask *mask); 2232 2233 #ifndef TASK_SIZE_OF 2234 #define TASK_SIZE_OF(tsk) TASK_SIZE 2235 #endif 2236 2237 #ifdef CONFIG_SMP 2238 static inline bool owner_on_cpu(struct task_struct *owner) 2239 { 2240 /* 2241 * As lock holder preemption issue, we both skip spinning if 2242 * task is not on cpu or its cpu is preempted 2243 */ 2244 return READ_ONCE(owner->on_cpu) && !vcpu_is_preempted(task_cpu(owner)); 2245 } 2246 2247 /* Returns effective CPU energy utilization, as seen by the scheduler */ 2248 unsigned long sched_cpu_util(int cpu); 2249 #endif /* CONFIG_SMP */ 2250 2251 #ifdef CONFIG_SCHED_CORE 2252 extern void sched_core_free(struct task_struct *tsk); 2253 extern void sched_core_fork(struct task_struct *p); 2254 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type, 2255 unsigned long uaddr); 2256 extern int sched_core_idle_cpu(int cpu); 2257 #else 2258 static inline void sched_core_free(struct task_struct *tsk) { } 2259 static inline void sched_core_fork(struct task_struct *p) { } 2260 static inline int sched_core_idle_cpu(int cpu) { return idle_cpu(cpu); } 2261 #endif 2262 2263 extern void sched_set_stop_task(int cpu, struct task_struct *stop); 2264 2265 #ifdef CONFIG_MEM_ALLOC_PROFILING 2266 static __always_inline struct alloc_tag *alloc_tag_save(struct alloc_tag *tag) 2267 { 2268 swap(current->alloc_tag, tag); 2269 return tag; 2270 } 2271 2272 static __always_inline void alloc_tag_restore(struct alloc_tag *tag, struct alloc_tag *old) 2273 { 2274 #ifdef CONFIG_MEM_ALLOC_PROFILING_DEBUG 2275 WARN(current->alloc_tag != tag, "current->alloc_tag was changed:\n"); 2276 #endif 2277 current->alloc_tag = old; 2278 } 2279 #else 2280 #define alloc_tag_save(_tag) NULL 2281 #define alloc_tag_restore(_tag, _old) do {} while (0) 2282 #endif 2283 2284 #endif 2285