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 /* Timestamps: */
402
403 /* When did we last run on a CPU? */
404 unsigned long long last_arrival;
405
406 /* When were we last queued to run? */
407 unsigned long long last_queued;
408
409 #endif /* CONFIG_SCHED_INFO */
410 };
411
412 /*
413 * Integer metrics need fixed point arithmetic, e.g., sched/fair
414 * has a few: load, load_avg, util_avg, freq, and capacity.
415 *
416 * We define a basic fixed point arithmetic range, and then formalize
417 * all these metrics based on that basic range.
418 */
419 # define SCHED_FIXEDPOINT_SHIFT 10
420 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT)
421
422 /* Increase resolution of cpu_capacity calculations */
423 # define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT
424 # define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT)
425
426 struct load_weight {
427 unsigned long weight;
428 u32 inv_weight;
429 };
430
431 /*
432 * The load/runnable/util_avg accumulates an infinite geometric series
433 * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c).
434 *
435 * [load_avg definition]
436 *
437 * load_avg = runnable% * scale_load_down(load)
438 *
439 * [runnable_avg definition]
440 *
441 * runnable_avg = runnable% * SCHED_CAPACITY_SCALE
442 *
443 * [util_avg definition]
444 *
445 * util_avg = running% * SCHED_CAPACITY_SCALE
446 *
447 * where runnable% is the time ratio that a sched_entity is runnable and
448 * running% the time ratio that a sched_entity is running.
449 *
450 * For cfs_rq, they are the aggregated values of all runnable and blocked
451 * sched_entities.
452 *
453 * The load/runnable/util_avg doesn't directly factor frequency scaling and CPU
454 * capacity scaling. The scaling is done through the rq_clock_pelt that is used
455 * for computing those signals (see update_rq_clock_pelt())
456 *
457 * N.B., the above ratios (runnable% and running%) themselves are in the
458 * range of [0, 1]. To do fixed point arithmetics, we therefore scale them
459 * to as large a range as necessary. This is for example reflected by
460 * util_avg's SCHED_CAPACITY_SCALE.
461 *
462 * [Overflow issue]
463 *
464 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
465 * with the highest load (=88761), always runnable on a single cfs_rq,
466 * and should not overflow as the number already hits PID_MAX_LIMIT.
467 *
468 * For all other cases (including 32-bit kernels), struct load_weight's
469 * weight will overflow first before we do, because:
470 *
471 * Max(load_avg) <= Max(load.weight)
472 *
473 * Then it is the load_weight's responsibility to consider overflow
474 * issues.
475 */
476 struct sched_avg {
477 u64 last_update_time;
478 u64 load_sum;
479 u64 runnable_sum;
480 u32 util_sum;
481 u32 period_contrib;
482 unsigned long load_avg;
483 unsigned long runnable_avg;
484 unsigned long util_avg;
485 unsigned int util_est;
486 } ____cacheline_aligned;
487
488 /*
489 * The UTIL_AVG_UNCHANGED flag is used to synchronize util_est with util_avg
490 * updates. When a task is dequeued, its util_est should not be updated if its
491 * util_avg has not been updated in the meantime.
492 * This information is mapped into the MSB bit of util_est at dequeue time.
493 * Since max value of util_est for a task is 1024 (PELT util_avg for a task)
494 * it is safe to use MSB.
495 */
496 #define UTIL_EST_WEIGHT_SHIFT 2
497 #define UTIL_AVG_UNCHANGED 0x80000000
498
499 struct sched_statistics {
500 #ifdef CONFIG_SCHEDSTATS
501 u64 wait_start;
502 u64 wait_max;
503 u64 wait_count;
504 u64 wait_sum;
505 u64 iowait_count;
506 u64 iowait_sum;
507
508 u64 sleep_start;
509 u64 sleep_max;
510 s64 sum_sleep_runtime;
511
512 u64 block_start;
513 u64 block_max;
514 s64 sum_block_runtime;
515
516 s64 exec_max;
517 u64 slice_max;
518
519 u64 nr_migrations_cold;
520 u64 nr_failed_migrations_affine;
521 u64 nr_failed_migrations_running;
522 u64 nr_failed_migrations_hot;
523 u64 nr_forced_migrations;
524
525 u64 nr_wakeups;
526 u64 nr_wakeups_sync;
527 u64 nr_wakeups_migrate;
528 u64 nr_wakeups_local;
529 u64 nr_wakeups_remote;
530 u64 nr_wakeups_affine;
531 u64 nr_wakeups_affine_attempts;
532 u64 nr_wakeups_passive;
533 u64 nr_wakeups_idle;
534
535 #ifdef CONFIG_SCHED_CORE
536 u64 core_forceidle_sum;
537 #endif
538 #endif /* CONFIG_SCHEDSTATS */
539 } ____cacheline_aligned;
540
541 struct sched_entity {
542 /* For load-balancing: */
543 struct load_weight load;
544 struct rb_node run_node;
545 u64 deadline;
546 u64 min_vruntime;
547 u64 min_slice;
548
549 struct list_head group_node;
550 unsigned char on_rq;
551 unsigned char sched_delayed;
552 unsigned char rel_deadline;
553 unsigned char custom_slice;
554 /* hole */
555
556 u64 exec_start;
557 u64 sum_exec_runtime;
558 u64 prev_sum_exec_runtime;
559 u64 vruntime;
560 s64 vlag;
561 u64 slice;
562
563 u64 nr_migrations;
564
565 #ifdef CONFIG_FAIR_GROUP_SCHED
566 int depth;
567 struct sched_entity *parent;
568 /* rq on which this entity is (to be) queued: */
569 struct cfs_rq *cfs_rq;
570 /* rq "owned" by this entity/group: */
571 struct cfs_rq *my_q;
572 /* cached value of my_q->h_nr_running */
573 unsigned long runnable_weight;
574 #endif
575
576 #ifdef CONFIG_SMP
577 /*
578 * Per entity load average tracking.
579 *
580 * Put into separate cache line so it does not
581 * collide with read-mostly values above.
582 */
583 struct sched_avg avg;
584 #endif
585 };
586
587 struct sched_rt_entity {
588 struct list_head run_list;
589 unsigned long timeout;
590 unsigned long watchdog_stamp;
591 unsigned int time_slice;
592 unsigned short on_rq;
593 unsigned short on_list;
594
595 struct sched_rt_entity *back;
596 #ifdef CONFIG_RT_GROUP_SCHED
597 struct sched_rt_entity *parent;
598 /* rq on which this entity is (to be) queued: */
599 struct rt_rq *rt_rq;
600 /* rq "owned" by this entity/group: */
601 struct rt_rq *my_q;
602 #endif
603 } __randomize_layout;
604
605 typedef bool (*dl_server_has_tasks_f)(struct sched_dl_entity *);
606 typedef struct task_struct *(*dl_server_pick_f)(struct sched_dl_entity *);
607
608 struct sched_dl_entity {
609 struct rb_node rb_node;
610
611 /*
612 * Original scheduling parameters. Copied here from sched_attr
613 * during sched_setattr(), they will remain the same until
614 * the next sched_setattr().
615 */
616 u64 dl_runtime; /* Maximum runtime for each instance */
617 u64 dl_deadline; /* Relative deadline of each instance */
618 u64 dl_period; /* Separation of two instances (period) */
619 u64 dl_bw; /* dl_runtime / dl_period */
620 u64 dl_density; /* dl_runtime / dl_deadline */
621
622 /*
623 * Actual scheduling parameters. Initialized with the values above,
624 * they are continuously updated during task execution. Note that
625 * the remaining runtime could be < 0 in case we are in overrun.
626 */
627 s64 runtime; /* Remaining runtime for this instance */
628 u64 deadline; /* Absolute deadline for this instance */
629 unsigned int flags; /* Specifying the scheduler behaviour */
630
631 /*
632 * Some bool flags:
633 *
634 * @dl_throttled tells if we exhausted the runtime. If so, the
635 * task has to wait for a replenishment to be performed at the
636 * next firing of dl_timer.
637 *
638 * @dl_yielded tells if task gave up the CPU before consuming
639 * all its available runtime during the last job.
640 *
641 * @dl_non_contending tells if the task is inactive while still
642 * contributing to the active utilization. In other words, it
643 * indicates if the inactive timer has been armed and its handler
644 * has not been executed yet. This flag is useful to avoid race
645 * conditions between the inactive timer handler and the wakeup
646 * code.
647 *
648 * @dl_overrun tells if the task asked to be informed about runtime
649 * overruns.
650 *
651 * @dl_server tells if this is a server entity.
652 *
653 * @dl_defer tells if this is a deferred or regular server. For
654 * now only defer server exists.
655 *
656 * @dl_defer_armed tells if the deferrable server is waiting
657 * for the replenishment timer to activate it.
658 *
659 * @dl_server_active tells if the dlserver is active(started).
660 * dlserver is started on first cfs enqueue on an idle runqueue
661 * and is stopped when a dequeue results in 0 cfs tasks on the
662 * runqueue. In other words, dlserver is active only when cpu's
663 * runqueue has atleast one cfs task.
664 *
665 * @dl_defer_running tells if the deferrable server is actually
666 * running, skipping the defer phase.
667 */
668 unsigned int dl_throttled : 1;
669 unsigned int dl_yielded : 1;
670 unsigned int dl_non_contending : 1;
671 unsigned int dl_overrun : 1;
672 unsigned int dl_server : 1;
673 unsigned int dl_server_active : 1;
674 unsigned int dl_defer : 1;
675 unsigned int dl_defer_armed : 1;
676 unsigned int dl_defer_running : 1;
677
678 /*
679 * Bandwidth enforcement timer. Each -deadline task has its
680 * own bandwidth to be enforced, thus we need one timer per task.
681 */
682 struct hrtimer dl_timer;
683
684 /*
685 * Inactive timer, responsible for decreasing the active utilization
686 * at the "0-lag time". When a -deadline task blocks, it contributes
687 * to GRUB's active utilization until the "0-lag time", hence a
688 * timer is needed to decrease the active utilization at the correct
689 * time.
690 */
691 struct hrtimer inactive_timer;
692
693 /*
694 * Bits for DL-server functionality. Also see the comment near
695 * dl_server_update().
696 *
697 * @rq the runqueue this server is for
698 *
699 * @server_has_tasks() returns true if @server_pick return a
700 * runnable task.
701 */
702 struct rq *rq;
703 dl_server_has_tasks_f server_has_tasks;
704 dl_server_pick_f server_pick_task;
705
706 #ifdef CONFIG_RT_MUTEXES
707 /*
708 * Priority Inheritance. When a DEADLINE scheduling entity is boosted
709 * pi_se points to the donor, otherwise points to the dl_se it belongs
710 * to (the original one/itself).
711 */
712 struct sched_dl_entity *pi_se;
713 #endif
714 };
715
716 #ifdef CONFIG_UCLAMP_TASK
717 /* Number of utilization clamp buckets (shorter alias) */
718 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT
719
720 /*
721 * Utilization clamp for a scheduling entity
722 * @value: clamp value "assigned" to a se
723 * @bucket_id: bucket index corresponding to the "assigned" value
724 * @active: the se is currently refcounted in a rq's bucket
725 * @user_defined: the requested clamp value comes from user-space
726 *
727 * The bucket_id is the index of the clamp bucket matching the clamp value
728 * which is pre-computed and stored to avoid expensive integer divisions from
729 * the fast path.
730 *
731 * The active bit is set whenever a task has got an "effective" value assigned,
732 * which can be different from the clamp value "requested" from user-space.
733 * This allows to know a task is refcounted in the rq's bucket corresponding
734 * to the "effective" bucket_id.
735 *
736 * The user_defined bit is set whenever a task has got a task-specific clamp
737 * value requested from userspace, i.e. the system defaults apply to this task
738 * just as a restriction. This allows to relax default clamps when a less
739 * restrictive task-specific value has been requested, thus allowing to
740 * implement a "nice" semantic. For example, a task running with a 20%
741 * default boost can still drop its own boosting to 0%.
742 */
743 struct uclamp_se {
744 unsigned int value : bits_per(SCHED_CAPACITY_SCALE);
745 unsigned int bucket_id : bits_per(UCLAMP_BUCKETS);
746 unsigned int active : 1;
747 unsigned int user_defined : 1;
748 };
749 #endif /* CONFIG_UCLAMP_TASK */
750
751 union rcu_special {
752 struct {
753 u8 blocked;
754 u8 need_qs;
755 u8 exp_hint; /* Hint for performance. */
756 u8 need_mb; /* Readers need smp_mb(). */
757 } b; /* Bits. */
758 u32 s; /* Set of bits. */
759 };
760
761 enum perf_event_task_context {
762 perf_invalid_context = -1,
763 perf_hw_context = 0,
764 perf_sw_context,
765 perf_nr_task_contexts,
766 };
767
768 /*
769 * Number of contexts where an event can trigger:
770 * task, softirq, hardirq, nmi.
771 */
772 #define PERF_NR_CONTEXTS 4
773
774 struct wake_q_node {
775 struct wake_q_node *next;
776 };
777
778 struct kmap_ctrl {
779 #ifdef CONFIG_KMAP_LOCAL
780 int idx;
781 pte_t pteval[KM_MAX_IDX];
782 #endif
783 };
784
785 struct task_struct {
786 #ifdef CONFIG_THREAD_INFO_IN_TASK
787 /*
788 * For reasons of header soup (see current_thread_info()), this
789 * must be the first element of task_struct.
790 */
791 struct thread_info thread_info;
792 #endif
793 unsigned int __state;
794
795 /* saved state for "spinlock sleepers" */
796 unsigned int saved_state;
797
798 /*
799 * This begins the randomizable portion of task_struct. Only
800 * scheduling-critical items should be added above here.
801 */
802 randomized_struct_fields_start
803
804 void *stack;
805 refcount_t usage;
806 /* Per task flags (PF_*), defined further below: */
807 unsigned int flags;
808 unsigned int ptrace;
809
810 #ifdef CONFIG_MEM_ALLOC_PROFILING
811 struct alloc_tag *alloc_tag;
812 #endif
813
814 #ifdef CONFIG_SMP
815 int on_cpu;
816 struct __call_single_node wake_entry;
817 unsigned int wakee_flips;
818 unsigned long wakee_flip_decay_ts;
819 struct task_struct *last_wakee;
820
821 /*
822 * recent_used_cpu is initially set as the last CPU used by a task
823 * that wakes affine another task. Waker/wakee relationships can
824 * push tasks around a CPU where each wakeup moves to the next one.
825 * Tracking a recently used CPU allows a quick search for a recently
826 * used CPU that may be idle.
827 */
828 int recent_used_cpu;
829 int wake_cpu;
830 #endif
831 int on_rq;
832
833 int prio;
834 int static_prio;
835 int normal_prio;
836 unsigned int rt_priority;
837
838 struct sched_entity se;
839 struct sched_rt_entity rt;
840 struct sched_dl_entity dl;
841 struct sched_dl_entity *dl_server;
842 #ifdef CONFIG_SCHED_CLASS_EXT
843 struct sched_ext_entity scx;
844 #endif
845 const struct sched_class *sched_class;
846
847 #ifdef CONFIG_SCHED_CORE
848 struct rb_node core_node;
849 unsigned long core_cookie;
850 unsigned int core_occupation;
851 #endif
852
853 #ifdef CONFIG_CGROUP_SCHED
854 struct task_group *sched_task_group;
855 #endif
856
857
858 #ifdef CONFIG_UCLAMP_TASK
859 /*
860 * Clamp values requested for a scheduling entity.
861 * Must be updated with task_rq_lock() held.
862 */
863 struct uclamp_se uclamp_req[UCLAMP_CNT];
864 /*
865 * Effective clamp values used for a scheduling entity.
866 * Must be updated with task_rq_lock() held.
867 */
868 struct uclamp_se uclamp[UCLAMP_CNT];
869 #endif
870
871 struct sched_statistics stats;
872
873 #ifdef CONFIG_PREEMPT_NOTIFIERS
874 /* List of struct preempt_notifier: */
875 struct hlist_head preempt_notifiers;
876 #endif
877
878 #ifdef CONFIG_BLK_DEV_IO_TRACE
879 unsigned int btrace_seq;
880 #endif
881
882 unsigned int policy;
883 unsigned long max_allowed_capacity;
884 int nr_cpus_allowed;
885 const cpumask_t *cpus_ptr;
886 cpumask_t *user_cpus_ptr;
887 cpumask_t cpus_mask;
888 void *migration_pending;
889 #ifdef CONFIG_SMP
890 unsigned short migration_disabled;
891 #endif
892 unsigned short migration_flags;
893
894 #ifdef CONFIG_PREEMPT_RCU
895 int rcu_read_lock_nesting;
896 union rcu_special rcu_read_unlock_special;
897 struct list_head rcu_node_entry;
898 struct rcu_node *rcu_blocked_node;
899 #endif /* #ifdef CONFIG_PREEMPT_RCU */
900
901 #ifdef CONFIG_TASKS_RCU
902 unsigned long rcu_tasks_nvcsw;
903 u8 rcu_tasks_holdout;
904 u8 rcu_tasks_idx;
905 int rcu_tasks_idle_cpu;
906 struct list_head rcu_tasks_holdout_list;
907 int rcu_tasks_exit_cpu;
908 struct list_head rcu_tasks_exit_list;
909 #endif /* #ifdef CONFIG_TASKS_RCU */
910
911 #ifdef CONFIG_TASKS_TRACE_RCU
912 int trc_reader_nesting;
913 int trc_ipi_to_cpu;
914 union rcu_special trc_reader_special;
915 struct list_head trc_holdout_list;
916 struct list_head trc_blkd_node;
917 int trc_blkd_cpu;
918 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */
919
920 struct sched_info sched_info;
921
922 struct list_head tasks;
923 #ifdef CONFIG_SMP
924 struct plist_node pushable_tasks;
925 struct rb_node pushable_dl_tasks;
926 #endif
927
928 struct mm_struct *mm;
929 struct mm_struct *active_mm;
930 struct address_space *faults_disabled_mapping;
931
932 int exit_state;
933 int exit_code;
934 int exit_signal;
935 /* The signal sent when the parent dies: */
936 int pdeath_signal;
937 /* JOBCTL_*, siglock protected: */
938 unsigned long jobctl;
939
940 /* Used for emulating ABI behavior of previous Linux versions: */
941 unsigned int personality;
942
943 /* Scheduler bits, serialized by scheduler locks: */
944 unsigned sched_reset_on_fork:1;
945 unsigned sched_contributes_to_load:1;
946 unsigned sched_migrated:1;
947
948 /* Force alignment to the next boundary: */
949 unsigned :0;
950
951 /* Unserialized, strictly 'current' */
952
953 /*
954 * This field must not be in the scheduler word above due to wakelist
955 * queueing no longer being serialized by p->on_cpu. However:
956 *
957 * p->XXX = X; ttwu()
958 * schedule() if (p->on_rq && ..) // false
959 * smp_mb__after_spinlock(); if (smp_load_acquire(&p->on_cpu) && //true
960 * deactivate_task() ttwu_queue_wakelist())
961 * p->on_rq = 0; p->sched_remote_wakeup = Y;
962 *
963 * guarantees all stores of 'current' are visible before
964 * ->sched_remote_wakeup gets used, so it can be in this word.
965 */
966 unsigned sched_remote_wakeup:1;
967 #ifdef CONFIG_RT_MUTEXES
968 unsigned sched_rt_mutex:1;
969 #endif
970
971 /* Bit to tell TOMOYO we're in execve(): */
972 unsigned in_execve:1;
973 unsigned in_iowait:1;
974 #ifndef TIF_RESTORE_SIGMASK
975 unsigned restore_sigmask:1;
976 #endif
977 #ifdef CONFIG_MEMCG_V1
978 unsigned in_user_fault:1;
979 #endif
980 #ifdef CONFIG_LRU_GEN
981 /* whether the LRU algorithm may apply to this access */
982 unsigned in_lru_fault:1;
983 #endif
984 #ifdef CONFIG_COMPAT_BRK
985 unsigned brk_randomized:1;
986 #endif
987 #ifdef CONFIG_CGROUPS
988 /* disallow userland-initiated cgroup migration */
989 unsigned no_cgroup_migration:1;
990 /* task is frozen/stopped (used by the cgroup freezer) */
991 unsigned frozen:1;
992 #endif
993 #ifdef CONFIG_BLK_CGROUP
994 unsigned use_memdelay:1;
995 #endif
996 #ifdef CONFIG_PSI
997 /* Stalled due to lack of memory */
998 unsigned in_memstall:1;
999 #endif
1000 #ifdef CONFIG_PAGE_OWNER
1001 /* Used by page_owner=on to detect recursion in page tracking. */
1002 unsigned in_page_owner:1;
1003 #endif
1004 #ifdef CONFIG_EVENTFD
1005 /* Recursion prevention for eventfd_signal() */
1006 unsigned in_eventfd:1;
1007 #endif
1008 #ifdef CONFIG_ARCH_HAS_CPU_PASID
1009 unsigned pasid_activated:1;
1010 #endif
1011 #ifdef CONFIG_X86_BUS_LOCK_DETECT
1012 unsigned reported_split_lock:1;
1013 #endif
1014 #ifdef CONFIG_TASK_DELAY_ACCT
1015 /* delay due to memory thrashing */
1016 unsigned in_thrashing:1;
1017 #endif
1018 #ifdef CONFIG_PREEMPT_RT
1019 struct netdev_xmit net_xmit;
1020 #endif
1021 unsigned long atomic_flags; /* Flags requiring atomic access. */
1022
1023 struct restart_block restart_block;
1024
1025 pid_t pid;
1026 pid_t tgid;
1027
1028 #ifdef CONFIG_STACKPROTECTOR
1029 /* Canary value for the -fstack-protector GCC feature: */
1030 unsigned long stack_canary;
1031 #endif
1032 /*
1033 * Pointers to the (original) parent process, youngest child, younger sibling,
1034 * older sibling, respectively. (p->father can be replaced with
1035 * p->real_parent->pid)
1036 */
1037
1038 /* Real parent process: */
1039 struct task_struct __rcu *real_parent;
1040
1041 /* Recipient of SIGCHLD, wait4() reports: */
1042 struct task_struct __rcu *parent;
1043
1044 /*
1045 * Children/sibling form the list of natural children:
1046 */
1047 struct list_head children;
1048 struct list_head sibling;
1049 struct task_struct *group_leader;
1050
1051 /*
1052 * 'ptraced' is the list of tasks this task is using ptrace() on.
1053 *
1054 * This includes both natural children and PTRACE_ATTACH targets.
1055 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
1056 */
1057 struct list_head ptraced;
1058 struct list_head ptrace_entry;
1059
1060 /* PID/PID hash table linkage. */
1061 struct pid *thread_pid;
1062 struct hlist_node pid_links[PIDTYPE_MAX];
1063 struct list_head thread_node;
1064
1065 struct completion *vfork_done;
1066
1067 /* CLONE_CHILD_SETTID: */
1068 int __user *set_child_tid;
1069
1070 /* CLONE_CHILD_CLEARTID: */
1071 int __user *clear_child_tid;
1072
1073 /* PF_KTHREAD | PF_IO_WORKER */
1074 void *worker_private;
1075
1076 u64 utime;
1077 u64 stime;
1078 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
1079 u64 utimescaled;
1080 u64 stimescaled;
1081 #endif
1082 u64 gtime;
1083 struct prev_cputime prev_cputime;
1084 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1085 struct vtime vtime;
1086 #endif
1087
1088 #ifdef CONFIG_NO_HZ_FULL
1089 atomic_t tick_dep_mask;
1090 #endif
1091 /* Context switch counts: */
1092 unsigned long nvcsw;
1093 unsigned long nivcsw;
1094
1095 /* Monotonic time in nsecs: */
1096 u64 start_time;
1097
1098 /* Boot based time in nsecs: */
1099 u64 start_boottime;
1100
1101 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
1102 unsigned long min_flt;
1103 unsigned long maj_flt;
1104
1105 /* Empty if CONFIG_POSIX_CPUTIMERS=n */
1106 struct posix_cputimers posix_cputimers;
1107
1108 #ifdef CONFIG_POSIX_CPU_TIMERS_TASK_WORK
1109 struct posix_cputimers_work posix_cputimers_work;
1110 #endif
1111
1112 /* Process credentials: */
1113
1114 /* Tracer's credentials at attach: */
1115 const struct cred __rcu *ptracer_cred;
1116
1117 /* Objective and real subjective task credentials (COW): */
1118 const struct cred __rcu *real_cred;
1119
1120 /* Effective (overridable) subjective task credentials (COW): */
1121 const struct cred __rcu *cred;
1122
1123 #ifdef CONFIG_KEYS
1124 /* Cached requested key. */
1125 struct key *cached_requested_key;
1126 #endif
1127
1128 /*
1129 * executable name, excluding path.
1130 *
1131 * - normally initialized begin_new_exec()
1132 * - set it with set_task_comm()
1133 * - strscpy_pad() to ensure it is always NUL-terminated and
1134 * zero-padded
1135 * - task_lock() to ensure the operation is atomic and the name is
1136 * fully updated.
1137 */
1138 char comm[TASK_COMM_LEN];
1139
1140 struct nameidata *nameidata;
1141
1142 #ifdef CONFIG_SYSVIPC
1143 struct sysv_sem sysvsem;
1144 struct sysv_shm sysvshm;
1145 #endif
1146 #ifdef CONFIG_DETECT_HUNG_TASK
1147 unsigned long last_switch_count;
1148 unsigned long last_switch_time;
1149 #endif
1150 /* Filesystem information: */
1151 struct fs_struct *fs;
1152
1153 /* Open file information: */
1154 struct files_struct *files;
1155
1156 #ifdef CONFIG_IO_URING
1157 struct io_uring_task *io_uring;
1158 #endif
1159
1160 /* Namespaces: */
1161 struct nsproxy *nsproxy;
1162
1163 /* Signal handlers: */
1164 struct signal_struct *signal;
1165 struct sighand_struct __rcu *sighand;
1166 sigset_t blocked;
1167 sigset_t real_blocked;
1168 /* Restored if set_restore_sigmask() was used: */
1169 sigset_t saved_sigmask;
1170 struct sigpending pending;
1171 unsigned long sas_ss_sp;
1172 size_t sas_ss_size;
1173 unsigned int sas_ss_flags;
1174
1175 struct callback_head *task_works;
1176
1177 #ifdef CONFIG_AUDIT
1178 #ifdef CONFIG_AUDITSYSCALL
1179 struct audit_context *audit_context;
1180 #endif
1181 kuid_t loginuid;
1182 unsigned int sessionid;
1183 #endif
1184 struct seccomp seccomp;
1185 struct syscall_user_dispatch syscall_dispatch;
1186
1187 /* Thread group tracking: */
1188 u64 parent_exec_id;
1189 u64 self_exec_id;
1190
1191 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
1192 spinlock_t alloc_lock;
1193
1194 /* Protection of the PI data structures: */
1195 raw_spinlock_t pi_lock;
1196
1197 struct wake_q_node wake_q;
1198
1199 #ifdef CONFIG_RT_MUTEXES
1200 /* PI waiters blocked on a rt_mutex held by this task: */
1201 struct rb_root_cached pi_waiters;
1202 /* Updated under owner's pi_lock and rq lock */
1203 struct task_struct *pi_top_task;
1204 /* Deadlock detection and priority inheritance handling: */
1205 struct rt_mutex_waiter *pi_blocked_on;
1206 #endif
1207
1208 #ifdef CONFIG_DEBUG_MUTEXES
1209 /* Mutex deadlock detection: */
1210 struct mutex_waiter *blocked_on;
1211 #endif
1212
1213 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1214 int non_block_count;
1215 #endif
1216
1217 #ifdef CONFIG_TRACE_IRQFLAGS
1218 struct irqtrace_events irqtrace;
1219 unsigned int hardirq_threaded;
1220 u64 hardirq_chain_key;
1221 int softirqs_enabled;
1222 int softirq_context;
1223 int irq_config;
1224 #endif
1225 #ifdef CONFIG_PREEMPT_RT
1226 int softirq_disable_cnt;
1227 #endif
1228
1229 #ifdef CONFIG_LOCKDEP
1230 # define MAX_LOCK_DEPTH 48UL
1231 u64 curr_chain_key;
1232 int lockdep_depth;
1233 unsigned int lockdep_recursion;
1234 struct held_lock held_locks[MAX_LOCK_DEPTH];
1235 #endif
1236
1237 #if defined(CONFIG_UBSAN) && !defined(CONFIG_UBSAN_TRAP)
1238 unsigned int in_ubsan;
1239 #endif
1240
1241 /* Journalling filesystem info: */
1242 void *journal_info;
1243
1244 /* Stacked block device info: */
1245 struct bio_list *bio_list;
1246
1247 /* Stack plugging: */
1248 struct blk_plug *plug;
1249
1250 /* VM state: */
1251 struct reclaim_state *reclaim_state;
1252
1253 struct io_context *io_context;
1254
1255 #ifdef CONFIG_COMPACTION
1256 struct capture_control *capture_control;
1257 #endif
1258 /* Ptrace state: */
1259 unsigned long ptrace_message;
1260 kernel_siginfo_t *last_siginfo;
1261
1262 struct task_io_accounting ioac;
1263 #ifdef CONFIG_PSI
1264 /* Pressure stall state */
1265 unsigned int psi_flags;
1266 #endif
1267 #ifdef CONFIG_TASK_XACCT
1268 /* Accumulated RSS usage: */
1269 u64 acct_rss_mem1;
1270 /* Accumulated virtual memory usage: */
1271 u64 acct_vm_mem1;
1272 /* stime + utime since last update: */
1273 u64 acct_timexpd;
1274 #endif
1275 #ifdef CONFIG_CPUSETS
1276 /* Protected by ->alloc_lock: */
1277 nodemask_t mems_allowed;
1278 /* Sequence number to catch updates: */
1279 seqcount_spinlock_t mems_allowed_seq;
1280 int cpuset_mem_spread_rotor;
1281 #endif
1282 #ifdef CONFIG_CGROUPS
1283 /* Control Group info protected by css_set_lock: */
1284 struct css_set __rcu *cgroups;
1285 /* cg_list protected by css_set_lock and tsk->alloc_lock: */
1286 struct list_head cg_list;
1287 #endif
1288 #ifdef CONFIG_X86_CPU_RESCTRL
1289 u32 closid;
1290 u32 rmid;
1291 #endif
1292 #ifdef CONFIG_FUTEX
1293 struct robust_list_head __user *robust_list;
1294 #ifdef CONFIG_COMPAT
1295 struct compat_robust_list_head __user *compat_robust_list;
1296 #endif
1297 struct list_head pi_state_list;
1298 struct futex_pi_state *pi_state_cache;
1299 struct mutex futex_exit_mutex;
1300 unsigned int futex_state;
1301 #endif
1302 #ifdef CONFIG_PERF_EVENTS
1303 u8 perf_recursion[PERF_NR_CONTEXTS];
1304 struct perf_event_context *perf_event_ctxp;
1305 struct mutex perf_event_mutex;
1306 struct list_head perf_event_list;
1307 #endif
1308 #ifdef CONFIG_DEBUG_PREEMPT
1309 unsigned long preempt_disable_ip;
1310 #endif
1311 #ifdef CONFIG_NUMA
1312 /* Protected by alloc_lock: */
1313 struct mempolicy *mempolicy;
1314 short il_prev;
1315 u8 il_weight;
1316 short pref_node_fork;
1317 #endif
1318 #ifdef CONFIG_NUMA_BALANCING
1319 int numa_scan_seq;
1320 unsigned int numa_scan_period;
1321 unsigned int numa_scan_period_max;
1322 int numa_preferred_nid;
1323 unsigned long numa_migrate_retry;
1324 /* Migration stamp: */
1325 u64 node_stamp;
1326 u64 last_task_numa_placement;
1327 u64 last_sum_exec_runtime;
1328 struct callback_head numa_work;
1329
1330 /*
1331 * This pointer is only modified for current in syscall and
1332 * pagefault context (and for tasks being destroyed), so it can be read
1333 * from any of the following contexts:
1334 * - RCU read-side critical section
1335 * - current->numa_group from everywhere
1336 * - task's runqueue locked, task not running
1337 */
1338 struct numa_group __rcu *numa_group;
1339
1340 /*
1341 * numa_faults is an array split into four regions:
1342 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1343 * in this precise order.
1344 *
1345 * faults_memory: Exponential decaying average of faults on a per-node
1346 * basis. Scheduling placement decisions are made based on these
1347 * counts. The values remain static for the duration of a PTE scan.
1348 * faults_cpu: Track the nodes the process was running on when a NUMA
1349 * hinting fault was incurred.
1350 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1351 * during the current scan window. When the scan completes, the counts
1352 * in faults_memory and faults_cpu decay and these values are copied.
1353 */
1354 unsigned long *numa_faults;
1355 unsigned long total_numa_faults;
1356
1357 /*
1358 * numa_faults_locality tracks if faults recorded during the last
1359 * scan window were remote/local or failed to migrate. The task scan
1360 * period is adapted based on the locality of the faults with different
1361 * weights depending on whether they were shared or private faults
1362 */
1363 unsigned long numa_faults_locality[3];
1364
1365 unsigned long numa_pages_migrated;
1366 #endif /* CONFIG_NUMA_BALANCING */
1367
1368 #ifdef CONFIG_RSEQ
1369 struct rseq __user *rseq;
1370 u32 rseq_len;
1371 u32 rseq_sig;
1372 /*
1373 * RmW on rseq_event_mask must be performed atomically
1374 * with respect to preemption.
1375 */
1376 unsigned long rseq_event_mask;
1377 #endif
1378
1379 #ifdef CONFIG_SCHED_MM_CID
1380 int mm_cid; /* Current cid in mm */
1381 int last_mm_cid; /* Most recent cid in mm */
1382 int migrate_from_cpu;
1383 int mm_cid_active; /* Whether cid bitmap is active */
1384 struct callback_head cid_work;
1385 #endif
1386
1387 struct tlbflush_unmap_batch tlb_ubc;
1388
1389 /* Cache last used pipe for splice(): */
1390 struct pipe_inode_info *splice_pipe;
1391
1392 struct page_frag task_frag;
1393
1394 #ifdef CONFIG_TASK_DELAY_ACCT
1395 struct task_delay_info *delays;
1396 #endif
1397
1398 #ifdef CONFIG_FAULT_INJECTION
1399 int make_it_fail;
1400 unsigned int fail_nth;
1401 #endif
1402 /*
1403 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1404 * balance_dirty_pages() for a dirty throttling pause:
1405 */
1406 int nr_dirtied;
1407 int nr_dirtied_pause;
1408 /* Start of a write-and-pause period: */
1409 unsigned long dirty_paused_when;
1410
1411 #ifdef CONFIG_LATENCYTOP
1412 int latency_record_count;
1413 struct latency_record latency_record[LT_SAVECOUNT];
1414 #endif
1415 /*
1416 * Time slack values; these are used to round up poll() and
1417 * select() etc timeout values. These are in nanoseconds.
1418 */
1419 u64 timer_slack_ns;
1420 u64 default_timer_slack_ns;
1421
1422 #if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
1423 unsigned int kasan_depth;
1424 #endif
1425
1426 #ifdef CONFIG_KCSAN
1427 struct kcsan_ctx kcsan_ctx;
1428 #ifdef CONFIG_TRACE_IRQFLAGS
1429 struct irqtrace_events kcsan_save_irqtrace;
1430 #endif
1431 #ifdef CONFIG_KCSAN_WEAK_MEMORY
1432 int kcsan_stack_depth;
1433 #endif
1434 #endif
1435
1436 #ifdef CONFIG_KMSAN
1437 struct kmsan_ctx kmsan_ctx;
1438 #endif
1439
1440 #if IS_ENABLED(CONFIG_KUNIT)
1441 struct kunit *kunit_test;
1442 #endif
1443
1444 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1445 /* Index of current stored address in ret_stack: */
1446 int curr_ret_stack;
1447 int curr_ret_depth;
1448
1449 /* Stack of return addresses for return function tracing: */
1450 unsigned long *ret_stack;
1451
1452 /* Timestamp for last schedule: */
1453 unsigned long long ftrace_timestamp;
1454 unsigned long long ftrace_sleeptime;
1455
1456 /*
1457 * Number of functions that haven't been traced
1458 * because of depth overrun:
1459 */
1460 atomic_t trace_overrun;
1461
1462 /* Pause tracing: */
1463 atomic_t tracing_graph_pause;
1464 #endif
1465
1466 #ifdef CONFIG_TRACING
1467 /* Bitmask and counter of trace recursion: */
1468 unsigned long trace_recursion;
1469 #endif /* CONFIG_TRACING */
1470
1471 #ifdef CONFIG_KCOV
1472 /* See kernel/kcov.c for more details. */
1473
1474 /* Coverage collection mode enabled for this task (0 if disabled): */
1475 unsigned int kcov_mode;
1476
1477 /* Size of the kcov_area: */
1478 unsigned int kcov_size;
1479
1480 /* Buffer for coverage collection: */
1481 void *kcov_area;
1482
1483 /* KCOV descriptor wired with this task or NULL: */
1484 struct kcov *kcov;
1485
1486 /* KCOV common handle for remote coverage collection: */
1487 u64 kcov_handle;
1488
1489 /* KCOV sequence number: */
1490 int kcov_sequence;
1491
1492 /* Collect coverage from softirq context: */
1493 unsigned int kcov_softirq;
1494 #endif
1495
1496 #ifdef CONFIG_MEMCG_V1
1497 struct mem_cgroup *memcg_in_oom;
1498 #endif
1499
1500 #ifdef CONFIG_MEMCG
1501 /* Number of pages to reclaim on returning to userland: */
1502 unsigned int memcg_nr_pages_over_high;
1503
1504 /* Used by memcontrol for targeted memcg charge: */
1505 struct mem_cgroup *active_memcg;
1506
1507 /* Cache for current->cgroups->memcg->objcg lookups: */
1508 struct obj_cgroup *objcg;
1509 #endif
1510
1511 #ifdef CONFIG_BLK_CGROUP
1512 struct gendisk *throttle_disk;
1513 #endif
1514
1515 #ifdef CONFIG_UPROBES
1516 struct uprobe_task *utask;
1517 #endif
1518 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1519 unsigned int sequential_io;
1520 unsigned int sequential_io_avg;
1521 #endif
1522 struct kmap_ctrl kmap_ctrl;
1523 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1524 unsigned long task_state_change;
1525 # ifdef CONFIG_PREEMPT_RT
1526 unsigned long saved_state_change;
1527 # endif
1528 #endif
1529 struct rcu_head rcu;
1530 refcount_t rcu_users;
1531 int pagefault_disabled;
1532 #ifdef CONFIG_MMU
1533 struct task_struct *oom_reaper_list;
1534 struct timer_list oom_reaper_timer;
1535 #endif
1536 #ifdef CONFIG_VMAP_STACK
1537 struct vm_struct *stack_vm_area;
1538 #endif
1539 #ifdef CONFIG_THREAD_INFO_IN_TASK
1540 /* A live task holds one reference: */
1541 refcount_t stack_refcount;
1542 #endif
1543 #ifdef CONFIG_LIVEPATCH
1544 int patch_state;
1545 #endif
1546 #ifdef CONFIG_SECURITY
1547 /* Used by LSM modules for access restriction: */
1548 void *security;
1549 #endif
1550 #ifdef CONFIG_BPF_SYSCALL
1551 /* Used by BPF task local storage */
1552 struct bpf_local_storage __rcu *bpf_storage;
1553 /* Used for BPF run context */
1554 struct bpf_run_ctx *bpf_ctx;
1555 #endif
1556 /* Used by BPF for per-TASK xdp storage */
1557 struct bpf_net_context *bpf_net_context;
1558
1559 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK
1560 unsigned long lowest_stack;
1561 unsigned long prev_lowest_stack;
1562 #endif
1563
1564 #ifdef CONFIG_X86_MCE
1565 void __user *mce_vaddr;
1566 __u64 mce_kflags;
1567 u64 mce_addr;
1568 __u64 mce_ripv : 1,
1569 mce_whole_page : 1,
1570 __mce_reserved : 62;
1571 struct callback_head mce_kill_me;
1572 int mce_count;
1573 #endif
1574
1575 #ifdef CONFIG_KRETPROBES
1576 struct llist_head kretprobe_instances;
1577 #endif
1578 #ifdef CONFIG_RETHOOK
1579 struct llist_head rethooks;
1580 #endif
1581
1582 #ifdef CONFIG_ARCH_HAS_PARANOID_L1D_FLUSH
1583 /*
1584 * If L1D flush is supported on mm context switch
1585 * then we use this callback head to queue kill work
1586 * to kill tasks that are not running on SMT disabled
1587 * cores
1588 */
1589 struct callback_head l1d_flush_kill;
1590 #endif
1591
1592 #ifdef CONFIG_RV
1593 /*
1594 * Per-task RV monitor. Nowadays fixed in RV_PER_TASK_MONITORS.
1595 * If we find justification for more monitors, we can think
1596 * about adding more or developing a dynamic method. So far,
1597 * none of these are justified.
1598 */
1599 union rv_task_monitor rv[RV_PER_TASK_MONITORS];
1600 #endif
1601
1602 #ifdef CONFIG_USER_EVENTS
1603 struct user_event_mm *user_event_mm;
1604 #endif
1605
1606 /*
1607 * New fields for task_struct should be added above here, so that
1608 * they are included in the randomized portion of task_struct.
1609 */
1610 randomized_struct_fields_end
1611
1612 /* CPU-specific state of this task: */
1613 struct thread_struct thread;
1614
1615 /*
1616 * WARNING: on x86, 'thread_struct' contains a variable-sized
1617 * structure. It *MUST* be at the end of 'task_struct'.
1618 *
1619 * Do not put anything below here!
1620 */
1621 };
1622
1623 #define TASK_REPORT_IDLE (TASK_REPORT + 1)
1624 #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1)
1625
__task_state_index(unsigned int tsk_state,unsigned int tsk_exit_state)1626 static inline unsigned int __task_state_index(unsigned int tsk_state,
1627 unsigned int tsk_exit_state)
1628 {
1629 unsigned int state = (tsk_state | tsk_exit_state) & TASK_REPORT;
1630
1631 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
1632
1633 if ((tsk_state & TASK_IDLE) == TASK_IDLE)
1634 state = TASK_REPORT_IDLE;
1635
1636 /*
1637 * We're lying here, but rather than expose a completely new task state
1638 * to userspace, we can make this appear as if the task has gone through
1639 * a regular rt_mutex_lock() call.
1640 */
1641 if (tsk_state & TASK_RTLOCK_WAIT)
1642 state = TASK_UNINTERRUPTIBLE;
1643
1644 return fls(state);
1645 }
1646
task_state_index(struct task_struct * tsk)1647 static inline unsigned int task_state_index(struct task_struct *tsk)
1648 {
1649 return __task_state_index(READ_ONCE(tsk->__state), tsk->exit_state);
1650 }
1651
task_index_to_char(unsigned int state)1652 static inline char task_index_to_char(unsigned int state)
1653 {
1654 static const char state_char[] = "RSDTtXZPI";
1655
1656 BUILD_BUG_ON(TASK_REPORT_MAX * 2 != 1 << (sizeof(state_char) - 1));
1657
1658 return state_char[state];
1659 }
1660
task_state_to_char(struct task_struct * tsk)1661 static inline char task_state_to_char(struct task_struct *tsk)
1662 {
1663 return task_index_to_char(task_state_index(tsk));
1664 }
1665
1666 extern struct pid *cad_pid;
1667
1668 /*
1669 * Per process flags
1670 */
1671 #define PF_VCPU 0x00000001 /* I'm a virtual CPU */
1672 #define PF_IDLE 0x00000002 /* I am an IDLE thread */
1673 #define PF_EXITING 0x00000004 /* Getting shut down */
1674 #define PF_POSTCOREDUMP 0x00000008 /* Coredumps should ignore this task */
1675 #define PF_IO_WORKER 0x00000010 /* Task is an IO worker */
1676 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */
1677 #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */
1678 #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */
1679 #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */
1680 #define PF_DUMPCORE 0x00000200 /* Dumped core */
1681 #define PF_SIGNALED 0x00000400 /* Killed by a signal */
1682 #define PF_MEMALLOC 0x00000800 /* Allocating memory to free memory. See memalloc_noreclaim_save() */
1683 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */
1684 #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */
1685 #define PF_USER_WORKER 0x00004000 /* Kernel thread cloned from userspace thread */
1686 #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */
1687 #define PF__HOLE__00010000 0x00010000
1688 #define PF_KSWAPD 0x00020000 /* I am kswapd */
1689 #define PF_MEMALLOC_NOFS 0x00040000 /* All allocations inherit GFP_NOFS. See memalloc_nfs_save() */
1690 #define PF_MEMALLOC_NOIO 0x00080000 /* All allocations inherit GFP_NOIO. See memalloc_noio_save() */
1691 #define PF_LOCAL_THROTTLE 0x00100000 /* Throttle writes only against the bdi I write to,
1692 * I am cleaning dirty pages from some other bdi. */
1693 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */
1694 #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */
1695 #define PF__HOLE__00800000 0x00800000
1696 #define PF__HOLE__01000000 0x01000000
1697 #define PF__HOLE__02000000 0x02000000
1698 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */
1699 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
1700 #define PF_MEMALLOC_PIN 0x10000000 /* Allocations constrained to zones which allow long term pinning.
1701 * See memalloc_pin_save() */
1702 #define PF_BLOCK_TS 0x20000000 /* plug has ts that needs updating */
1703 #define PF__HOLE__40000000 0x40000000
1704 #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */
1705
1706 /*
1707 * Only the _current_ task can read/write to tsk->flags, but other
1708 * tasks can access tsk->flags in readonly mode for example
1709 * with tsk_used_math (like during threaded core dumping).
1710 * There is however an exception to this rule during ptrace
1711 * or during fork: the ptracer task is allowed to write to the
1712 * child->flags of its traced child (same goes for fork, the parent
1713 * can write to the child->flags), because we're guaranteed the
1714 * child is not running and in turn not changing child->flags
1715 * at the same time the parent does it.
1716 */
1717 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1718 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1719 #define clear_used_math() clear_stopped_child_used_math(current)
1720 #define set_used_math() set_stopped_child_used_math(current)
1721
1722 #define conditional_stopped_child_used_math(condition, child) \
1723 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1724
1725 #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current)
1726
1727 #define copy_to_stopped_child_used_math(child) \
1728 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1729
1730 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1731 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1732 #define used_math() tsk_used_math(current)
1733
is_percpu_thread(void)1734 static __always_inline bool is_percpu_thread(void)
1735 {
1736 #ifdef CONFIG_SMP
1737 return (current->flags & PF_NO_SETAFFINITY) &&
1738 (current->nr_cpus_allowed == 1);
1739 #else
1740 return true;
1741 #endif
1742 }
1743
1744 /* Per-process atomic flags. */
1745 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */
1746 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */
1747 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */
1748 #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */
1749 #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/
1750 #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */
1751 #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */
1752 #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */
1753
1754 #define TASK_PFA_TEST(name, func) \
1755 static inline bool task_##func(struct task_struct *p) \
1756 { return test_bit(PFA_##name, &p->atomic_flags); }
1757
1758 #define TASK_PFA_SET(name, func) \
1759 static inline void task_set_##func(struct task_struct *p) \
1760 { set_bit(PFA_##name, &p->atomic_flags); }
1761
1762 #define TASK_PFA_CLEAR(name, func) \
1763 static inline void task_clear_##func(struct task_struct *p) \
1764 { clear_bit(PFA_##name, &p->atomic_flags); }
1765
TASK_PFA_TEST(NO_NEW_PRIVS,no_new_privs)1766 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1767 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1768
1769 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1770 TASK_PFA_SET(SPREAD_PAGE, spread_page)
1771 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1772
1773 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1774 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1775 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1776
1777 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable)
1778 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable)
1779 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable)
1780
1781 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1782 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1783 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1784
1785 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1786 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1787
1788 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable)
1789 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable)
1790 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable)
1791
1792 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1793 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1794
1795 static inline void
1796 current_restore_flags(unsigned long orig_flags, unsigned long flags)
1797 {
1798 current->flags &= ~flags;
1799 current->flags |= orig_flags & flags;
1800 }
1801
1802 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
1803 extern int task_can_attach(struct task_struct *p);
1804 extern int dl_bw_alloc(int cpu, u64 dl_bw);
1805 extern void dl_bw_free(int cpu, u64 dl_bw);
1806 #ifdef CONFIG_SMP
1807
1808 /* do_set_cpus_allowed() - consider using set_cpus_allowed_ptr() instead */
1809 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask);
1810
1811 /**
1812 * set_cpus_allowed_ptr - set CPU affinity mask of a task
1813 * @p: the task
1814 * @new_mask: CPU affinity mask
1815 *
1816 * Return: zero if successful, or a negative error code
1817 */
1818 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
1819 extern int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node);
1820 extern void release_user_cpus_ptr(struct task_struct *p);
1821 extern int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask);
1822 extern void force_compatible_cpus_allowed_ptr(struct task_struct *p);
1823 extern void relax_compatible_cpus_allowed_ptr(struct task_struct *p);
1824 #else
do_set_cpus_allowed(struct task_struct * p,const struct cpumask * new_mask)1825 static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
1826 {
1827 }
set_cpus_allowed_ptr(struct task_struct * p,const struct cpumask * new_mask)1828 static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
1829 {
1830 /* Opencoded cpumask_test_cpu(0, new_mask) to avoid dependency on cpumask.h */
1831 if ((*cpumask_bits(new_mask) & 1) == 0)
1832 return -EINVAL;
1833 return 0;
1834 }
dup_user_cpus_ptr(struct task_struct * dst,struct task_struct * src,int node)1835 static inline int dup_user_cpus_ptr(struct task_struct *dst, struct task_struct *src, int node)
1836 {
1837 if (src->user_cpus_ptr)
1838 return -EINVAL;
1839 return 0;
1840 }
release_user_cpus_ptr(struct task_struct * p)1841 static inline void release_user_cpus_ptr(struct task_struct *p)
1842 {
1843 WARN_ON(p->user_cpus_ptr);
1844 }
1845
dl_task_check_affinity(struct task_struct * p,const struct cpumask * mask)1846 static inline int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask)
1847 {
1848 return 0;
1849 }
1850 #endif
1851
1852 extern int yield_to(struct task_struct *p, bool preempt);
1853 extern void set_user_nice(struct task_struct *p, long nice);
1854 extern int task_prio(const struct task_struct *p);
1855
1856 /**
1857 * task_nice - return the nice value of a given task.
1858 * @p: the task in question.
1859 *
1860 * Return: The nice value [ -20 ... 0 ... 19 ].
1861 */
task_nice(const struct task_struct * p)1862 static inline int task_nice(const struct task_struct *p)
1863 {
1864 return PRIO_TO_NICE((p)->static_prio);
1865 }
1866
1867 extern int can_nice(const struct task_struct *p, const int nice);
1868 extern int task_curr(const struct task_struct *p);
1869 extern int idle_cpu(int cpu);
1870 extern int available_idle_cpu(int cpu);
1871 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
1872 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
1873 extern void sched_set_fifo(struct task_struct *p);
1874 extern void sched_set_fifo_low(struct task_struct *p);
1875 extern void sched_set_normal(struct task_struct *p, int nice);
1876 extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1877 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
1878 extern struct task_struct *idle_task(int cpu);
1879
1880 /**
1881 * is_idle_task - is the specified task an idle task?
1882 * @p: the task in question.
1883 *
1884 * Return: 1 if @p is an idle task. 0 otherwise.
1885 */
is_idle_task(const struct task_struct * p)1886 static __always_inline bool is_idle_task(const struct task_struct *p)
1887 {
1888 return !!(p->flags & PF_IDLE);
1889 }
1890
1891 extern struct task_struct *curr_task(int cpu);
1892 extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1893
1894 void yield(void);
1895
1896 union thread_union {
1897 struct task_struct task;
1898 #ifndef CONFIG_THREAD_INFO_IN_TASK
1899 struct thread_info thread_info;
1900 #endif
1901 unsigned long stack[THREAD_SIZE/sizeof(long)];
1902 };
1903
1904 #ifndef CONFIG_THREAD_INFO_IN_TASK
1905 extern struct thread_info init_thread_info;
1906 #endif
1907
1908 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
1909
1910 #ifdef CONFIG_THREAD_INFO_IN_TASK
1911 # define task_thread_info(task) (&(task)->thread_info)
1912 #else
1913 # define task_thread_info(task) ((struct thread_info *)(task)->stack)
1914 #endif
1915
1916 /*
1917 * find a task by one of its numerical ids
1918 *
1919 * find_task_by_pid_ns():
1920 * finds a task by its pid in the specified namespace
1921 * find_task_by_vpid():
1922 * finds a task by its virtual pid
1923 *
1924 * see also find_vpid() etc in include/linux/pid.h
1925 */
1926
1927 extern struct task_struct *find_task_by_vpid(pid_t nr);
1928 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
1929
1930 /*
1931 * find a task by its virtual pid and get the task struct
1932 */
1933 extern struct task_struct *find_get_task_by_vpid(pid_t nr);
1934
1935 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1936 extern int wake_up_process(struct task_struct *tsk);
1937 extern void wake_up_new_task(struct task_struct *tsk);
1938
1939 #ifdef CONFIG_SMP
1940 extern void kick_process(struct task_struct *tsk);
1941 #else
kick_process(struct task_struct * tsk)1942 static inline void kick_process(struct task_struct *tsk) { }
1943 #endif
1944
1945 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
1946
set_task_comm(struct task_struct * tsk,const char * from)1947 static inline void set_task_comm(struct task_struct *tsk, const char *from)
1948 {
1949 __set_task_comm(tsk, from, false);
1950 }
1951
1952 /*
1953 * - Why not use task_lock()?
1954 * User space can randomly change their names anyway, so locking for readers
1955 * doesn't make sense. For writers, locking is probably necessary, as a race
1956 * condition could lead to long-term mixed results.
1957 * The strscpy_pad() in __set_task_comm() can ensure that the task comm is
1958 * always NUL-terminated and zero-padded. Therefore the race condition between
1959 * reader and writer is not an issue.
1960 *
1961 * - BUILD_BUG_ON() can help prevent the buf from being truncated.
1962 * Since the callers don't perform any return value checks, this safeguard is
1963 * necessary.
1964 */
1965 #define get_task_comm(buf, tsk) ({ \
1966 BUILD_BUG_ON(sizeof(buf) < TASK_COMM_LEN); \
1967 strscpy_pad(buf, (tsk)->comm); \
1968 buf; \
1969 })
1970
1971 #ifdef CONFIG_SMP
scheduler_ipi(void)1972 static __always_inline void scheduler_ipi(void)
1973 {
1974 /*
1975 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
1976 * TIF_NEED_RESCHED remotely (for the first time) will also send
1977 * this IPI.
1978 */
1979 preempt_fold_need_resched();
1980 }
1981 #else
scheduler_ipi(void)1982 static inline void scheduler_ipi(void) { }
1983 #endif
1984
1985 extern unsigned long wait_task_inactive(struct task_struct *, unsigned int match_state);
1986
1987 /*
1988 * Set thread flags in other task's structures.
1989 * See asm/thread_info.h for TIF_xxxx flags available:
1990 */
set_tsk_thread_flag(struct task_struct * tsk,int flag)1991 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1992 {
1993 set_ti_thread_flag(task_thread_info(tsk), flag);
1994 }
1995
clear_tsk_thread_flag(struct task_struct * tsk,int flag)1996 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1997 {
1998 clear_ti_thread_flag(task_thread_info(tsk), flag);
1999 }
2000
update_tsk_thread_flag(struct task_struct * tsk,int flag,bool value)2001 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag,
2002 bool value)
2003 {
2004 update_ti_thread_flag(task_thread_info(tsk), flag, value);
2005 }
2006
test_and_set_tsk_thread_flag(struct task_struct * tsk,int flag)2007 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2008 {
2009 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2010 }
2011
test_and_clear_tsk_thread_flag(struct task_struct * tsk,int flag)2012 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2013 {
2014 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2015 }
2016
test_tsk_thread_flag(struct task_struct * tsk,int flag)2017 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2018 {
2019 return test_ti_thread_flag(task_thread_info(tsk), flag);
2020 }
2021
set_tsk_need_resched(struct task_struct * tsk)2022 static inline void set_tsk_need_resched(struct task_struct *tsk)
2023 {
2024 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2025 }
2026
clear_tsk_need_resched(struct task_struct * tsk)2027 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2028 {
2029 atomic_long_andnot(_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY,
2030 (atomic_long_t *)&task_thread_info(tsk)->flags);
2031 }
2032
test_tsk_need_resched(struct task_struct * tsk)2033 static inline int test_tsk_need_resched(struct task_struct *tsk)
2034 {
2035 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2036 }
2037
2038 /*
2039 * cond_resched() and cond_resched_lock(): latency reduction via
2040 * explicit rescheduling in places that are safe. The return
2041 * value indicates whether a reschedule was done in fact.
2042 * cond_resched_lock() will drop the spinlock before scheduling,
2043 */
2044 #if !defined(CONFIG_PREEMPTION) || defined(CONFIG_PREEMPT_DYNAMIC)
2045 extern int __cond_resched(void);
2046
2047 #if defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_CALL)
2048
2049 void sched_dynamic_klp_enable(void);
2050 void sched_dynamic_klp_disable(void);
2051
2052 DECLARE_STATIC_CALL(cond_resched, __cond_resched);
2053
_cond_resched(void)2054 static __always_inline int _cond_resched(void)
2055 {
2056 return static_call_mod(cond_resched)();
2057 }
2058
2059 #elif defined(CONFIG_PREEMPT_DYNAMIC) && defined(CONFIG_HAVE_PREEMPT_DYNAMIC_KEY)
2060
2061 extern int dynamic_cond_resched(void);
2062
_cond_resched(void)2063 static __always_inline int _cond_resched(void)
2064 {
2065 return dynamic_cond_resched();
2066 }
2067
2068 #else /* !CONFIG_PREEMPTION */
2069
_cond_resched(void)2070 static inline int _cond_resched(void)
2071 {
2072 klp_sched_try_switch();
2073 return __cond_resched();
2074 }
2075
2076 #endif /* PREEMPT_DYNAMIC && CONFIG_HAVE_PREEMPT_DYNAMIC_CALL */
2077
2078 #else /* CONFIG_PREEMPTION && !CONFIG_PREEMPT_DYNAMIC */
2079
_cond_resched(void)2080 static inline int _cond_resched(void)
2081 {
2082 klp_sched_try_switch();
2083 return 0;
2084 }
2085
2086 #endif /* !CONFIG_PREEMPTION || CONFIG_PREEMPT_DYNAMIC */
2087
2088 #define cond_resched() ({ \
2089 __might_resched(__FILE__, __LINE__, 0); \
2090 _cond_resched(); \
2091 })
2092
2093 extern int __cond_resched_lock(spinlock_t *lock);
2094 extern int __cond_resched_rwlock_read(rwlock_t *lock);
2095 extern int __cond_resched_rwlock_write(rwlock_t *lock);
2096
2097 #define MIGHT_RESCHED_RCU_SHIFT 8
2098 #define MIGHT_RESCHED_PREEMPT_MASK ((1U << MIGHT_RESCHED_RCU_SHIFT) - 1)
2099
2100 #ifndef CONFIG_PREEMPT_RT
2101 /*
2102 * Non RT kernels have an elevated preempt count due to the held lock,
2103 * but are not allowed to be inside a RCU read side critical section
2104 */
2105 # define PREEMPT_LOCK_RESCHED_OFFSETS PREEMPT_LOCK_OFFSET
2106 #else
2107 /*
2108 * spin/rw_lock() on RT implies rcu_read_lock(). The might_sleep() check in
2109 * cond_resched*lock() has to take that into account because it checks for
2110 * preempt_count() and rcu_preempt_depth().
2111 */
2112 # define PREEMPT_LOCK_RESCHED_OFFSETS \
2113 (PREEMPT_LOCK_OFFSET + (1U << MIGHT_RESCHED_RCU_SHIFT))
2114 #endif
2115
2116 #define cond_resched_lock(lock) ({ \
2117 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \
2118 __cond_resched_lock(lock); \
2119 })
2120
2121 #define cond_resched_rwlock_read(lock) ({ \
2122 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \
2123 __cond_resched_rwlock_read(lock); \
2124 })
2125
2126 #define cond_resched_rwlock_write(lock) ({ \
2127 __might_resched(__FILE__, __LINE__, PREEMPT_LOCK_RESCHED_OFFSETS); \
2128 __cond_resched_rwlock_write(lock); \
2129 })
2130
need_resched(void)2131 static __always_inline bool need_resched(void)
2132 {
2133 return unlikely(tif_need_resched());
2134 }
2135
2136 /*
2137 * Wrappers for p->thread_info->cpu access. No-op on UP.
2138 */
2139 #ifdef CONFIG_SMP
2140
task_cpu(const struct task_struct * p)2141 static inline unsigned int task_cpu(const struct task_struct *p)
2142 {
2143 return READ_ONCE(task_thread_info(p)->cpu);
2144 }
2145
2146 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2147
2148 #else
2149
task_cpu(const struct task_struct * p)2150 static inline unsigned int task_cpu(const struct task_struct *p)
2151 {
2152 return 0;
2153 }
2154
set_task_cpu(struct task_struct * p,unsigned int cpu)2155 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2156 {
2157 }
2158
2159 #endif /* CONFIG_SMP */
2160
task_is_runnable(struct task_struct * p)2161 static inline bool task_is_runnable(struct task_struct *p)
2162 {
2163 return p->on_rq && !p->se.sched_delayed;
2164 }
2165
2166 extern bool sched_task_on_rq(struct task_struct *p);
2167 extern unsigned long get_wchan(struct task_struct *p);
2168 extern struct task_struct *cpu_curr_snapshot(int cpu);
2169
2170 #include <linux/spinlock.h>
2171
2172 /*
2173 * In order to reduce various lock holder preemption latencies provide an
2174 * interface to see if a vCPU is currently running or not.
2175 *
2176 * This allows us to terminate optimistic spin loops and block, analogous to
2177 * the native optimistic spin heuristic of testing if the lock owner task is
2178 * running or not.
2179 */
2180 #ifndef vcpu_is_preempted
vcpu_is_preempted(int cpu)2181 static inline bool vcpu_is_preempted(int cpu)
2182 {
2183 return false;
2184 }
2185 #endif
2186
2187 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2188 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2189
2190 #ifndef TASK_SIZE_OF
2191 #define TASK_SIZE_OF(tsk) TASK_SIZE
2192 #endif
2193
2194 #ifdef CONFIG_SMP
owner_on_cpu(struct task_struct * owner)2195 static inline bool owner_on_cpu(struct task_struct *owner)
2196 {
2197 /*
2198 * As lock holder preemption issue, we both skip spinning if
2199 * task is not on cpu or its cpu is preempted
2200 */
2201 return READ_ONCE(owner->on_cpu) && !vcpu_is_preempted(task_cpu(owner));
2202 }
2203
2204 /* Returns effective CPU energy utilization, as seen by the scheduler */
2205 unsigned long sched_cpu_util(int cpu);
2206 #endif /* CONFIG_SMP */
2207
2208 #ifdef CONFIG_SCHED_CORE
2209 extern void sched_core_free(struct task_struct *tsk);
2210 extern void sched_core_fork(struct task_struct *p);
2211 extern int sched_core_share_pid(unsigned int cmd, pid_t pid, enum pid_type type,
2212 unsigned long uaddr);
2213 extern int sched_core_idle_cpu(int cpu);
2214 #else
sched_core_free(struct task_struct * tsk)2215 static inline void sched_core_free(struct task_struct *tsk) { }
sched_core_fork(struct task_struct * p)2216 static inline void sched_core_fork(struct task_struct *p) { }
sched_core_idle_cpu(int cpu)2217 static inline int sched_core_idle_cpu(int cpu) { return idle_cpu(cpu); }
2218 #endif
2219
2220 extern void sched_set_stop_task(int cpu, struct task_struct *stop);
2221
2222 #ifdef CONFIG_MEM_ALLOC_PROFILING
alloc_tag_save(struct alloc_tag * tag)2223 static __always_inline struct alloc_tag *alloc_tag_save(struct alloc_tag *tag)
2224 {
2225 swap(current->alloc_tag, tag);
2226 return tag;
2227 }
2228
alloc_tag_restore(struct alloc_tag * tag,struct alloc_tag * old)2229 static __always_inline void alloc_tag_restore(struct alloc_tag *tag, struct alloc_tag *old)
2230 {
2231 #ifdef CONFIG_MEM_ALLOC_PROFILING_DEBUG
2232 WARN(current->alloc_tag != tag, "current->alloc_tag was changed:\n");
2233 #endif
2234 current->alloc_tag = old;
2235 }
2236 #else
2237 #define alloc_tag_save(_tag) NULL
2238 #define alloc_tag_restore(_tag, _old) do {} while (0)
2239 #endif
2240
2241 #endif
2242