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