1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_SCHED_H
3#define _LINUX_SCHED_H
4
5/*
6 * Define 'struct task_struct' and provide the main scheduler
7 * APIs (schedule(), wakeup variants, etc.)
8 */
9
10#include <uapi/linux/sched.h>
11
12#include <asm/current.h>
13
14#include <linux/pid.h>
15#include <linux/sem.h>
16#include <linux/shm.h>
17#include <linux/kcov.h>
18#include <linux/mutex.h>
19#include <linux/plist.h>
20#include <linux/hrtimer.h>
21#include <linux/seccomp.h>
22#include <linux/nodemask.h>
23#include <linux/rcupdate.h>
24#include <linux/resource.h>
25#include <linux/latencytop.h>
26#include <linux/sched/prio.h>
27#include <linux/signal_types.h>
28#include <linux/mm_types_task.h>
29#include <linux/task_io_accounting.h>
30
31/* task_struct member predeclarations (sorted alphabetically): */
32struct audit_context;
33struct backing_dev_info;
34struct bio_list;
35struct blk_plug;
36struct cfs_rq;
37struct fs_struct;
38struct futex_pi_state;
39struct io_context;
40struct mempolicy;
41struct nameidata;
42struct nsproxy;
43struct perf_event_context;
44struct pid_namespace;
45struct pipe_inode_info;
46struct rcu_node;
47struct reclaim_state;
48struct robust_list_head;
49struct sched_attr;
50struct sched_param;
51struct seq_file;
52struct sighand_struct;
53struct signal_struct;
54struct task_delay_info;
55struct task_group;
56
57/*
58 * Task state bitmask. NOTE! These bits are also
59 * encoded in fs/proc/array.c: get_task_state().
60 *
61 * We have two separate sets of flags: task->state
62 * is about runnability, while task->exit_state are
63 * about the task exiting. Confusing, but this way
64 * modifying one set can't modify the other one by
65 * mistake.
66 */
67
68/* Used in tsk->state: */
69#define TASK_RUNNING 0x0000
70#define TASK_INTERRUPTIBLE 0x0001
71#define TASK_UNINTERRUPTIBLE 0x0002
72#define __TASK_STOPPED 0x0004
73#define __TASK_TRACED 0x0008
74/* Used in tsk->exit_state: */
75#define EXIT_DEAD 0x0010
76#define EXIT_ZOMBIE 0x0020
77#define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD)
78/* Used in tsk->state again: */
79#define TASK_PARKED 0x0040
80#define TASK_DEAD 0x0080
81#define TASK_WAKEKILL 0x0100
82#define TASK_WAKING 0x0200
83#define TASK_NOLOAD 0x0400
84#define TASK_NEW 0x0800
85#define TASK_STATE_MAX 0x1000
86
87/* Convenience macros for the sake of set_current_state: */
88#define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
89#define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
90#define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED)
91
92#define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
93
94/* Convenience macros for the sake of wake_up(): */
95#define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
96#define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
97
98/* get_task_state(): */
99#define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \
100 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
101 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
102 TASK_PARKED)
103
104#define task_is_traced(task) ((task->state & __TASK_TRACED) != 0)
105
106#define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0)
107
108#define task_is_stopped_or_traced(task) ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
109
110#define task_contributes_to_load(task) ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
111 (task->flags & PF_FROZEN) == 0 && \
112 (task->state & TASK_NOLOAD) == 0)
113
114#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
115
116#define __set_current_state(state_value) \
117 do { \
118 current->task_state_change = _THIS_IP_; \
119 current->state = (state_value); \
120 } while (0)
121#define set_current_state(state_value) \
122 do { \
123 current->task_state_change = _THIS_IP_; \
124 smp_store_mb(current->state, (state_value)); \
125 } while (0)
126
127#else
128/*
129 * set_current_state() includes a barrier so that the write of current->state
130 * is correctly serialised wrt the caller's subsequent test of whether to
131 * actually sleep:
132 *
133 * for (;;) {
134 * set_current_state(TASK_UNINTERRUPTIBLE);
135 * if (!need_sleep)
136 * break;
137 *
138 * schedule();
139 * }
140 * __set_current_state(TASK_RUNNING);
141 *
142 * If the caller does not need such serialisation (because, for instance, the
143 * condition test and condition change and wakeup are under the same lock) then
144 * use __set_current_state().
145 *
146 * The above is typically ordered against the wakeup, which does:
147 *
148 * need_sleep = false;
149 * wake_up_state(p, TASK_UNINTERRUPTIBLE);
150 *
151 * Where wake_up_state() (and all other wakeup primitives) imply enough
152 * barriers to order the store of the variable against wakeup.
153 *
154 * Wakeup will do: if (@state & p->state) p->state = TASK_RUNNING, that is,
155 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
156 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING).
157 *
158 * This is obviously fine, since they both store the exact same value.
159 *
160 * Also see the comments of try_to_wake_up().
161 */
162#define __set_current_state(state_value) do { current->state = (state_value); } while (0)
163#define set_current_state(state_value) smp_store_mb(current->state, (state_value))
164#endif
165
166/* Task command name length: */
167#define TASK_COMM_LEN 16
168
169extern void scheduler_tick(void);
170
171#define MAX_SCHEDULE_TIMEOUT LONG_MAX
172
173extern long schedule_timeout(long timeout);
174extern long schedule_timeout_interruptible(long timeout);
175extern long schedule_timeout_killable(long timeout);
176extern long schedule_timeout_uninterruptible(long timeout);
177extern long schedule_timeout_idle(long timeout);
178asmlinkage void schedule(void);
179extern void schedule_preempt_disabled(void);
180
181extern int __must_check io_schedule_prepare(void);
182extern void io_schedule_finish(int token);
183extern long io_schedule_timeout(long timeout);
184extern void io_schedule(void);
185
186/**
187 * struct prev_cputime - snapshot of system and user cputime
188 * @utime: time spent in user mode
189 * @stime: time spent in system mode
190 * @lock: protects the above two fields
191 *
192 * Stores previous user/system time values such that we can guarantee
193 * monotonicity.
194 */
195struct prev_cputime {
196#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
197 u64 utime;
198 u64 stime;
199 raw_spinlock_t lock;
200#endif
201};
202
203/**
204 * struct task_cputime - collected CPU time counts
205 * @utime: time spent in user mode, in nanoseconds
206 * @stime: time spent in kernel mode, in nanoseconds
207 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds
208 *
209 * This structure groups together three kinds of CPU time that are tracked for
210 * threads and thread groups. Most things considering CPU time want to group
211 * these counts together and treat all three of them in parallel.
212 */
213struct task_cputime {
214 u64 utime;
215 u64 stime;
216 unsigned long long sum_exec_runtime;
217};
218
219/* Alternate field names when used on cache expirations: */
220#define virt_exp utime
221#define prof_exp stime
222#define sched_exp sum_exec_runtime
223
224enum vtime_state {
225 /* Task is sleeping or running in a CPU with VTIME inactive: */
226 VTIME_INACTIVE = 0,
227 /* Task runs in userspace in a CPU with VTIME active: */
228 VTIME_USER,
229 /* Task runs in kernelspace in a CPU with VTIME active: */
230 VTIME_SYS,
231};
232
233struct vtime {
234 seqcount_t seqcount;
235 unsigned long long starttime;
236 enum vtime_state state;
237 u64 utime;
238 u64 stime;
239 u64 gtime;
240};
241
242struct sched_info {
243#ifdef CONFIG_SCHED_INFO
244 /* Cumulative counters: */
245
246 /* # of times we have run on this CPU: */
247 unsigned long pcount;
248
249 /* Time spent waiting on a runqueue: */
250 unsigned long long run_delay;
251
252 /* Timestamps: */
253
254 /* When did we last run on a CPU? */
255 unsigned long long last_arrival;
256
257 /* When were we last queued to run? */
258 unsigned long long last_queued;
259
260#endif /* CONFIG_SCHED_INFO */
261};
262
263/*
264 * Integer metrics need fixed point arithmetic, e.g., sched/fair
265 * has a few: load, load_avg, util_avg, freq, and capacity.
266 *
267 * We define a basic fixed point arithmetic range, and then formalize
268 * all these metrics based on that basic range.
269 */
270# define SCHED_FIXEDPOINT_SHIFT 10
271# define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT)
272
273struct load_weight {
274 unsigned long weight;
275 u32 inv_weight;
276};
277
278/*
279 * The load_avg/util_avg accumulates an infinite geometric series
280 * (see __update_load_avg() in kernel/sched/fair.c).
281 *
282 * [load_avg definition]
283 *
284 * load_avg = runnable% * scale_load_down(load)
285 *
286 * where runnable% is the time ratio that a sched_entity is runnable.
287 * For cfs_rq, it is the aggregated load_avg of all runnable and
288 * blocked sched_entities.
289 *
290 * load_avg may also take frequency scaling into account:
291 *
292 * load_avg = runnable% * scale_load_down(load) * freq%
293 *
294 * where freq% is the CPU frequency normalized to the highest frequency.
295 *
296 * [util_avg definition]
297 *
298 * util_avg = running% * SCHED_CAPACITY_SCALE
299 *
300 * where running% is the time ratio that a sched_entity is running on
301 * a CPU. For cfs_rq, it is the aggregated util_avg of all runnable
302 * and blocked sched_entities.
303 *
304 * util_avg may also factor frequency scaling and CPU capacity scaling:
305 *
306 * util_avg = running% * SCHED_CAPACITY_SCALE * freq% * capacity%
307 *
308 * where freq% is the same as above, and capacity% is the CPU capacity
309 * normalized to the greatest capacity (due to uarch differences, etc).
310 *
311 * N.B., the above ratios (runnable%, running%, freq%, and capacity%)
312 * themselves are in the range of [0, 1]. To do fixed point arithmetics,
313 * we therefore scale them to as large a range as necessary. This is for
314 * example reflected by util_avg's SCHED_CAPACITY_SCALE.
315 *
316 * [Overflow issue]
317 *
318 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
319 * with the highest load (=88761), always runnable on a single cfs_rq,
320 * and should not overflow as the number already hits PID_MAX_LIMIT.
321 *
322 * For all other cases (including 32-bit kernels), struct load_weight's
323 * weight will overflow first before we do, because:
324 *
325 * Max(load_avg) <= Max(load.weight)
326 *
327 * Then it is the load_weight's responsibility to consider overflow
328 * issues.
329 */
330struct sched_avg {
331 u64 last_update_time;
332 u64 load_sum;
333 u64 runnable_load_sum;
334 u32 util_sum;
335 u32 period_contrib;
336 unsigned long load_avg;
337 unsigned long runnable_load_avg;
338 unsigned long util_avg;
339};
340
341struct sched_statistics {
342#ifdef CONFIG_SCHEDSTATS
343 u64 wait_start;
344 u64 wait_max;
345 u64 wait_count;
346 u64 wait_sum;
347 u64 iowait_count;
348 u64 iowait_sum;
349
350 u64 sleep_start;
351 u64 sleep_max;
352 s64 sum_sleep_runtime;
353
354 u64 block_start;
355 u64 block_max;
356 u64 exec_max;
357 u64 slice_max;
358
359 u64 nr_migrations_cold;
360 u64 nr_failed_migrations_affine;
361 u64 nr_failed_migrations_running;
362 u64 nr_failed_migrations_hot;
363 u64 nr_forced_migrations;
364
365 u64 nr_wakeups;
366 u64 nr_wakeups_sync;
367 u64 nr_wakeups_migrate;
368 u64 nr_wakeups_local;
369 u64 nr_wakeups_remote;
370 u64 nr_wakeups_affine;
371 u64 nr_wakeups_affine_attempts;
372 u64 nr_wakeups_passive;
373 u64 nr_wakeups_idle;
374#endif
375};
376
377struct sched_entity {
378 /* For load-balancing: */
379 struct load_weight load;
380 unsigned long runnable_weight;
381 struct rb_node run_node;
382 struct list_head group_node;
383 unsigned int on_rq;
384
385 u64 exec_start;
386 u64 sum_exec_runtime;
387 u64 vruntime;
388 u64 prev_sum_exec_runtime;
389
390 u64 nr_migrations;
391
392 struct sched_statistics statistics;
393
394#ifdef CONFIG_FAIR_GROUP_SCHED
395 int depth;
396 struct sched_entity *parent;
397 /* rq on which this entity is (to be) queued: */
398 struct cfs_rq *cfs_rq;
399 /* rq "owned" by this entity/group: */
400 struct cfs_rq *my_q;
401#endif
402
403#ifdef CONFIG_SMP
404 /*
405 * Per entity load average tracking.
406 *
407 * Put into separate cache line so it does not
408 * collide with read-mostly values above.
409 */
410 struct sched_avg avg ____cacheline_aligned_in_smp;
411#endif
412};
413
414struct sched_rt_entity {
415 struct list_head run_list;
416 unsigned long timeout;
417 unsigned long watchdog_stamp;
418 unsigned int time_slice;
419 unsigned short on_rq;
420 unsigned short on_list;
421
422 struct sched_rt_entity *back;
423#ifdef CONFIG_RT_GROUP_SCHED
424 struct sched_rt_entity *parent;
425 /* rq on which this entity is (to be) queued: */
426 struct rt_rq *rt_rq;
427 /* rq "owned" by this entity/group: */
428 struct rt_rq *my_q;
429#endif
430} __randomize_layout;
431
432struct sched_dl_entity {
433 struct rb_node rb_node;
434
435 /*
436 * Original scheduling parameters. Copied here from sched_attr
437 * during sched_setattr(), they will remain the same until
438 * the next sched_setattr().
439 */
440 u64 dl_runtime; /* Maximum runtime for each instance */
441 u64 dl_deadline; /* Relative deadline of each instance */
442 u64 dl_period; /* Separation of two instances (period) */
443 u64 dl_bw; /* dl_runtime / dl_period */
444 u64 dl_density; /* dl_runtime / dl_deadline */
445
446 /*
447 * Actual scheduling parameters. Initialized with the values above,
448 * they are continously updated during task execution. Note that
449 * the remaining runtime could be < 0 in case we are in overrun.
450 */
451 s64 runtime; /* Remaining runtime for this instance */
452 u64 deadline; /* Absolute deadline for this instance */
453 unsigned int flags; /* Specifying the scheduler behaviour */
454
455 /*
456 * Some bool flags:
457 *
458 * @dl_throttled tells if we exhausted the runtime. If so, the
459 * task has to wait for a replenishment to be performed at the
460 * next firing of dl_timer.
461 *
462 * @dl_boosted tells if we are boosted due to DI. If so we are
463 * outside bandwidth enforcement mechanism (but only until we
464 * exit the critical section);
465 *
466 * @dl_yielded tells if task gave up the CPU before consuming
467 * all its available runtime during the last job.
468 *
469 * @dl_non_contending tells if the task is inactive while still
470 * contributing to the active utilization. In other words, it
471 * indicates if the inactive timer has been armed and its handler
472 * has not been executed yet. This flag is useful to avoid race
473 * conditions between the inactive timer handler and the wakeup
474 * code.
475 *
476 * @dl_overrun tells if the task asked to be informed about runtime
477 * overruns.
478 */
479 unsigned int dl_throttled : 1;
480 unsigned int dl_boosted : 1;
481 unsigned int dl_yielded : 1;
482 unsigned int dl_non_contending : 1;
483 unsigned int dl_overrun : 1;
484
485 /*
486 * Bandwidth enforcement timer. Each -deadline task has its
487 * own bandwidth to be enforced, thus we need one timer per task.
488 */
489 struct hrtimer dl_timer;
490
491 /*
492 * Inactive timer, responsible for decreasing the active utilization
493 * at the "0-lag time". When a -deadline task blocks, it contributes
494 * to GRUB's active utilization until the "0-lag time", hence a
495 * timer is needed to decrease the active utilization at the correct
496 * time.
497 */
498 struct hrtimer inactive_timer;
499};
500
501union rcu_special {
502 struct {
503 u8 blocked;
504 u8 need_qs;
505 u8 exp_need_qs;
506
507 /* Otherwise the compiler can store garbage here: */
508 u8 pad;
509 } b; /* Bits. */
510 u32 s; /* Set of bits. */
511};
512
513enum perf_event_task_context {
514 perf_invalid_context = -1,
515 perf_hw_context = 0,
516 perf_sw_context,
517 perf_nr_task_contexts,
518};
519
520struct wake_q_node {
521 struct wake_q_node *next;
522};
523
524struct task_struct {
525#ifdef CONFIG_THREAD_INFO_IN_TASK
526 /*
527 * For reasons of header soup (see current_thread_info()), this
528 * must be the first element of task_struct.
529 */
530 struct thread_info thread_info;
531#endif
532 /* -1 unrunnable, 0 runnable, >0 stopped: */
533 volatile long state;
534
535 /*
536 * This begins the randomizable portion of task_struct. Only
537 * scheduling-critical items should be added above here.
538 */
539 randomized_struct_fields_start
540
541 void *stack;
542 atomic_t usage;
543 /* Per task flags (PF_*), defined further below: */
544 unsigned int flags;
545 unsigned int ptrace;
546
547#ifdef CONFIG_SMP
548 struct llist_node wake_entry;
549 int on_cpu;
550#ifdef CONFIG_THREAD_INFO_IN_TASK
551 /* Current CPU: */
552 unsigned int cpu;
553#endif
554 unsigned int wakee_flips;
555 unsigned long wakee_flip_decay_ts;
556 struct task_struct *last_wakee;
557
558 /*
559 * recent_used_cpu is initially set as the last CPU used by a task
560 * that wakes affine another task. Waker/wakee relationships can
561 * push tasks around a CPU where each wakeup moves to the next one.
562 * Tracking a recently used CPU allows a quick search for a recently
563 * used CPU that may be idle.
564 */
565 int recent_used_cpu;
566 int wake_cpu;
567#endif
568 int on_rq;
569
570 int prio;
571 int static_prio;
572 int normal_prio;
573 unsigned int rt_priority;
574
575 const struct sched_class *sched_class;
576 struct sched_entity se;
577 struct sched_rt_entity rt;
578#ifdef CONFIG_CGROUP_SCHED
579 struct task_group *sched_task_group;
580#endif
581 struct sched_dl_entity dl;
582
583#ifdef CONFIG_PREEMPT_NOTIFIERS
584 /* List of struct preempt_notifier: */
585 struct hlist_head preempt_notifiers;
586#endif
587
588#ifdef CONFIG_BLK_DEV_IO_TRACE
589 unsigned int btrace_seq;
590#endif
591
592 unsigned int policy;
593 int nr_cpus_allowed;
594 cpumask_t cpus_allowed;
595
596#ifdef CONFIG_PREEMPT_RCU
597 int rcu_read_lock_nesting;
598 union rcu_special rcu_read_unlock_special;
599 struct list_head rcu_node_entry;
600 struct rcu_node *rcu_blocked_node;
601#endif /* #ifdef CONFIG_PREEMPT_RCU */
602
603#ifdef CONFIG_TASKS_RCU
604 unsigned long rcu_tasks_nvcsw;
605 u8 rcu_tasks_holdout;
606 u8 rcu_tasks_idx;
607 int rcu_tasks_idle_cpu;
608 struct list_head rcu_tasks_holdout_list;
609#endif /* #ifdef CONFIG_TASKS_RCU */
610
611 struct sched_info sched_info;
612
613 struct list_head tasks;
614#ifdef CONFIG_SMP
615 struct plist_node pushable_tasks;
616 struct rb_node pushable_dl_tasks;
617#endif
618
619 struct mm_struct *mm;
620 struct mm_struct *active_mm;
621
622 /* Per-thread vma caching: */
623 struct vmacache vmacache;
624
625#ifdef SPLIT_RSS_COUNTING
626 struct task_rss_stat rss_stat;
627#endif
628 int exit_state;
629 int exit_code;
630 int exit_signal;
631 /* The signal sent when the parent dies: */
632 int pdeath_signal;
633 /* JOBCTL_*, siglock protected: */
634 unsigned long jobctl;
635
636 /* Used for emulating ABI behavior of previous Linux versions: */
637 unsigned int personality;
638
639 /* Scheduler bits, serialized by scheduler locks: */
640 unsigned sched_reset_on_fork:1;
641 unsigned sched_contributes_to_load:1;
642 unsigned sched_migrated:1;
643 unsigned sched_remote_wakeup:1;
644 /* Force alignment to the next boundary: */
645 unsigned :0;
646
647 /* Unserialized, strictly 'current' */
648
649 /* Bit to tell LSMs we're in execve(): */
650 unsigned in_execve:1;
651 unsigned in_iowait:1;
652#ifndef TIF_RESTORE_SIGMASK
653 unsigned restore_sigmask:1;
654#endif
655#ifdef CONFIG_MEMCG
656 unsigned memcg_may_oom:1;
657#ifndef CONFIG_SLOB
658 unsigned memcg_kmem_skip_account:1;
659#endif
660#endif
661#ifdef CONFIG_COMPAT_BRK
662 unsigned brk_randomized:1;
663#endif
664#ifdef CONFIG_CGROUPS
665 /* disallow userland-initiated cgroup migration */
666 unsigned no_cgroup_migration:1;
667#endif
668
669 unsigned long atomic_flags; /* Flags requiring atomic access. */
670
671 struct restart_block restart_block;
672
673 pid_t pid;
674 pid_t tgid;
675
676#ifdef CONFIG_CC_STACKPROTECTOR
677 /* Canary value for the -fstack-protector GCC feature: */
678 unsigned long stack_canary;
679#endif
680 /*
681 * Pointers to the (original) parent process, youngest child, younger sibling,
682 * older sibling, respectively. (p->father can be replaced with
683 * p->real_parent->pid)
684 */
685
686 /* Real parent process: */
687 struct task_struct __rcu *real_parent;
688
689 /* Recipient of SIGCHLD, wait4() reports: */
690 struct task_struct __rcu *parent;
691
692 /*
693 * Children/sibling form the list of natural children:
694 */
695 struct list_head children;
696 struct list_head sibling;
697 struct task_struct *group_leader;
698
699 /*
700 * 'ptraced' is the list of tasks this task is using ptrace() on.
701 *
702 * This includes both natural children and PTRACE_ATTACH targets.
703 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
704 */
705 struct list_head ptraced;
706 struct list_head ptrace_entry;
707
708 /* PID/PID hash table linkage. */
709 struct pid_link pids[PIDTYPE_MAX];
710 struct list_head thread_group;
711 struct list_head thread_node;
712
713 struct completion *vfork_done;
714
715 /* CLONE_CHILD_SETTID: */
716 int __user *set_child_tid;
717
718 /* CLONE_CHILD_CLEARTID: */
719 int __user *clear_child_tid;
720
721 u64 utime;
722 u64 stime;
723#ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
724 u64 utimescaled;
725 u64 stimescaled;
726#endif
727 u64 gtime;
728 struct prev_cputime prev_cputime;
729#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
730 struct vtime vtime;
731#endif
732
733#ifdef CONFIG_NO_HZ_FULL
734 atomic_t tick_dep_mask;
735#endif
736 /* Context switch counts: */
737 unsigned long nvcsw;
738 unsigned long nivcsw;
739
740 /* Monotonic time in nsecs: */
741 u64 start_time;
742
743 /* Boot based time in nsecs: */
744 u64 real_start_time;
745
746 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
747 unsigned long min_flt;
748 unsigned long maj_flt;
749
750#ifdef CONFIG_POSIX_TIMERS
751 struct task_cputime cputime_expires;
752 struct list_head cpu_timers[3];
753#endif
754
755 /* Process credentials: */
756
757 /* Tracer's credentials at attach: */
758 const struct cred __rcu *ptracer_cred;
759
760 /* Objective and real subjective task credentials (COW): */
761 const struct cred __rcu *real_cred;
762
763 /* Effective (overridable) subjective task credentials (COW): */
764 const struct cred __rcu *cred;
765
766 /*
767 * executable name, excluding path.
768 *
769 * - normally initialized setup_new_exec()
770 * - access it with [gs]et_task_comm()
771 * - lock it with task_lock()
772 */
773 char comm[TASK_COMM_LEN];
774
775 struct nameidata *nameidata;
776
777#ifdef CONFIG_SYSVIPC
778 struct sysv_sem sysvsem;
779 struct sysv_shm sysvshm;
780#endif
781#ifdef CONFIG_DETECT_HUNG_TASK
782 unsigned long last_switch_count;
783#endif
784 /* Filesystem information: */
785 struct fs_struct *fs;
786
787 /* Open file information: */
788 struct files_struct *files;
789
790 /* Namespaces: */
791 struct nsproxy *nsproxy;
792
793 /* Signal handlers: */
794 struct signal_struct *signal;
795 struct sighand_struct *sighand;
796 sigset_t blocked;
797 sigset_t real_blocked;
798 /* Restored if set_restore_sigmask() was used: */
799 sigset_t saved_sigmask;
800 struct sigpending pending;
801 unsigned long sas_ss_sp;
802 size_t sas_ss_size;
803 unsigned int sas_ss_flags;
804
805 struct callback_head *task_works;
806
807 struct audit_context *audit_context;
808#ifdef CONFIG_AUDITSYSCALL
809 kuid_t loginuid;
810 unsigned int sessionid;
811#endif
812 struct seccomp seccomp;
813
814 /* Thread group tracking: */
815 u32 parent_exec_id;
816 u32 self_exec_id;
817
818 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
819 spinlock_t alloc_lock;
820
821 /* Protection of the PI data structures: */
822 raw_spinlock_t pi_lock;
823
824 struct wake_q_node wake_q;
825
826#ifdef CONFIG_RT_MUTEXES
827 /* PI waiters blocked on a rt_mutex held by this task: */
828 struct rb_root_cached pi_waiters;
829 /* Updated under owner's pi_lock and rq lock */
830 struct task_struct *pi_top_task;
831 /* Deadlock detection and priority inheritance handling: */
832 struct rt_mutex_waiter *pi_blocked_on;
833#endif
834
835#ifdef CONFIG_DEBUG_MUTEXES
836 /* Mutex deadlock detection: */
837 struct mutex_waiter *blocked_on;
838#endif
839
840#ifdef CONFIG_TRACE_IRQFLAGS
841 unsigned int irq_events;
842 unsigned long hardirq_enable_ip;
843 unsigned long hardirq_disable_ip;
844 unsigned int hardirq_enable_event;
845 unsigned int hardirq_disable_event;
846 int hardirqs_enabled;
847 int hardirq_context;
848 unsigned long softirq_disable_ip;
849 unsigned long softirq_enable_ip;
850 unsigned int softirq_disable_event;
851 unsigned int softirq_enable_event;
852 int softirqs_enabled;
853 int softirq_context;
854#endif
855
856#ifdef CONFIG_LOCKDEP
857# define MAX_LOCK_DEPTH 48UL
858 u64 curr_chain_key;
859 int lockdep_depth;
860 unsigned int lockdep_recursion;
861 struct held_lock held_locks[MAX_LOCK_DEPTH];
862#endif
863
864#ifdef CONFIG_UBSAN
865 unsigned int in_ubsan;
866#endif
867
868 /* Journalling filesystem info: */
869 void *journal_info;
870
871 /* Stacked block device info: */
872 struct bio_list *bio_list;
873
874#ifdef CONFIG_BLOCK
875 /* Stack plugging: */
876 struct blk_plug *plug;
877#endif
878
879 /* VM state: */
880 struct reclaim_state *reclaim_state;
881
882 struct backing_dev_info *backing_dev_info;
883
884 struct io_context *io_context;
885
886 /* Ptrace state: */
887 unsigned long ptrace_message;
888 siginfo_t *last_siginfo;
889
890 struct task_io_accounting ioac;
891#ifdef CONFIG_TASK_XACCT
892 /* Accumulated RSS usage: */
893 u64 acct_rss_mem1;
894 /* Accumulated virtual memory usage: */
895 u64 acct_vm_mem1;
896 /* stime + utime since last update: */
897 u64 acct_timexpd;
898#endif
899#ifdef CONFIG_CPUSETS
900 /* Protected by ->alloc_lock: */
901 nodemask_t mems_allowed;
902 /* Seqence number to catch updates: */
903 seqcount_t mems_allowed_seq;
904 int cpuset_mem_spread_rotor;
905 int cpuset_slab_spread_rotor;
906#endif
907#ifdef CONFIG_CGROUPS
908 /* Control Group info protected by css_set_lock: */
909 struct css_set __rcu *cgroups;
910 /* cg_list protected by css_set_lock and tsk->alloc_lock: */
911 struct list_head cg_list;
912#endif
913#ifdef CONFIG_INTEL_RDT
914 u32 closid;
915 u32 rmid;
916#endif
917#ifdef CONFIG_FUTEX
918 struct robust_list_head __user *robust_list;
919#ifdef CONFIG_COMPAT
920 struct compat_robust_list_head __user *compat_robust_list;
921#endif
922 struct list_head pi_state_list;
923 struct futex_pi_state *pi_state_cache;
924#endif
925#ifdef CONFIG_PERF_EVENTS
926 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
927 struct mutex perf_event_mutex;
928 struct list_head perf_event_list;
929#endif
930#ifdef CONFIG_DEBUG_PREEMPT
931 unsigned long preempt_disable_ip;
932#endif
933#ifdef CONFIG_NUMA
934 /* Protected by alloc_lock: */
935 struct mempolicy *mempolicy;
936 short il_prev;
937 short pref_node_fork;
938#endif
939#ifdef CONFIG_NUMA_BALANCING
940 int numa_scan_seq;
941 unsigned int numa_scan_period;
942 unsigned int numa_scan_period_max;
943 int numa_preferred_nid;
944 unsigned long numa_migrate_retry;
945 /* Migration stamp: */
946 u64 node_stamp;
947 u64 last_task_numa_placement;
948 u64 last_sum_exec_runtime;
949 struct callback_head numa_work;
950
951 struct list_head numa_entry;
952 struct numa_group *numa_group;
953
954 /*
955 * numa_faults is an array split into four regions:
956 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
957 * in this precise order.
958 *
959 * faults_memory: Exponential decaying average of faults on a per-node
960 * basis. Scheduling placement decisions are made based on these
961 * counts. The values remain static for the duration of a PTE scan.
962 * faults_cpu: Track the nodes the process was running on when a NUMA
963 * hinting fault was incurred.
964 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
965 * during the current scan window. When the scan completes, the counts
966 * in faults_memory and faults_cpu decay and these values are copied.
967 */
968 unsigned long *numa_faults;
969 unsigned long total_numa_faults;
970
971 /*
972 * numa_faults_locality tracks if faults recorded during the last
973 * scan window were remote/local or failed to migrate. The task scan
974 * period is adapted based on the locality of the faults with different
975 * weights depending on whether they were shared or private faults
976 */
977 unsigned long numa_faults_locality[3];
978
979 unsigned long numa_pages_migrated;
980#endif /* CONFIG_NUMA_BALANCING */
981
982 struct tlbflush_unmap_batch tlb_ubc;
983
984 struct rcu_head rcu;
985
986 /* Cache last used pipe for splice(): */
987 struct pipe_inode_info *splice_pipe;
988
989 struct page_frag task_frag;
990
991#ifdef CONFIG_TASK_DELAY_ACCT
992 struct task_delay_info *delays;
993#endif
994
995#ifdef CONFIG_FAULT_INJECTION
996 int make_it_fail;
997 unsigned int fail_nth;
998#endif
999 /*
1000 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1001 * balance_dirty_pages() for a dirty throttling pause:
1002 */
1003 int nr_dirtied;
1004 int nr_dirtied_pause;
1005 /* Start of a write-and-pause period: */
1006 unsigned long dirty_paused_when;
1007
1008#ifdef CONFIG_LATENCYTOP
1009 int latency_record_count;
1010 struct latency_record latency_record[LT_SAVECOUNT];
1011#endif
1012 /*
1013 * Time slack values; these are used to round up poll() and
1014 * select() etc timeout values. These are in nanoseconds.
1015 */
1016 u64 timer_slack_ns;
1017 u64 default_timer_slack_ns;
1018
1019#ifdef CONFIG_KASAN
1020 unsigned int kasan_depth;
1021#endif
1022
1023#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1024 /* Index of current stored address in ret_stack: */
1025 int curr_ret_stack;
1026
1027 /* Stack of return addresses for return function tracing: */
1028 struct ftrace_ret_stack *ret_stack;
1029
1030 /* Timestamp for last schedule: */
1031 unsigned long long ftrace_timestamp;
1032
1033 /*
1034 * Number of functions that haven't been traced
1035 * because of depth overrun:
1036 */
1037 atomic_t trace_overrun;
1038
1039 /* Pause tracing: */
1040 atomic_t tracing_graph_pause;
1041#endif
1042
1043#ifdef CONFIG_TRACING
1044 /* State flags for use by tracers: */
1045 unsigned long trace;
1046
1047 /* Bitmask and counter of trace recursion: */
1048 unsigned long trace_recursion;
1049#endif /* CONFIG_TRACING */
1050
1051#ifdef CONFIG_KCOV
1052 /* Coverage collection mode enabled for this task (0 if disabled): */
1053 enum kcov_mode kcov_mode;
1054
1055 /* Size of the kcov_area: */
1056 unsigned int kcov_size;
1057
1058 /* Buffer for coverage collection: */
1059 void *kcov_area;
1060
1061 /* KCOV descriptor wired with this task or NULL: */
1062 struct kcov *kcov;
1063#endif
1064
1065#ifdef CONFIG_MEMCG
1066 struct mem_cgroup *memcg_in_oom;
1067 gfp_t memcg_oom_gfp_mask;
1068 int memcg_oom_order;
1069
1070 /* Number of pages to reclaim on returning to userland: */
1071 unsigned int memcg_nr_pages_over_high;
1072#endif
1073
1074#ifdef CONFIG_UPROBES
1075 struct uprobe_task *utask;
1076#endif
1077#if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1078 unsigned int sequential_io;
1079 unsigned int sequential_io_avg;
1080#endif
1081#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1082 unsigned long task_state_change;
1083#endif
1084 int pagefault_disabled;
1085#ifdef CONFIG_MMU
1086 struct task_struct *oom_reaper_list;
1087#endif
1088#ifdef CONFIG_VMAP_STACK
1089 struct vm_struct *stack_vm_area;
1090#endif
1091#ifdef CONFIG_THREAD_INFO_IN_TASK
1092 /* A live task holds one reference: */
1093 atomic_t stack_refcount;
1094#endif
1095#ifdef CONFIG_LIVEPATCH
1096 int patch_state;
1097#endif
1098#ifdef CONFIG_SECURITY
1099 /* Used by LSM modules for access restriction: */
1100 void *security;
1101#endif
1102
1103 /*
1104 * New fields for task_struct should be added above here, so that
1105 * they are included in the randomized portion of task_struct.
1106 */
1107 randomized_struct_fields_end
1108
1109 /* CPU-specific state of this task: */
1110 struct thread_struct thread;
1111
1112 /*
1113 * WARNING: on x86, 'thread_struct' contains a variable-sized
1114 * structure. It *MUST* be at the end of 'task_struct'.
1115 *
1116 * Do not put anything below here!
1117 */
1118};
1119
1120static inline struct pid *task_pid(struct task_struct *task)
1121{
1122 return task->pids[PIDTYPE_PID].pid;
1123}
1124
1125static inline struct pid *task_tgid(struct task_struct *task)
1126{
1127 return task->group_leader->pids[PIDTYPE_PID].pid;
1128}
1129
1130/*
1131 * Without tasklist or RCU lock it is not safe to dereference
1132 * the result of task_pgrp/task_session even if task == current,
1133 * we can race with another thread doing sys_setsid/sys_setpgid.
1134 */
1135static inline struct pid *task_pgrp(struct task_struct *task)
1136{
1137 return task->group_leader->pids[PIDTYPE_PGID].pid;
1138}
1139
1140static inline struct pid *task_session(struct task_struct *task)
1141{
1142 return task->group_leader->pids[PIDTYPE_SID].pid;
1143}
1144
1145/*
1146 * the helpers to get the task's different pids as they are seen
1147 * from various namespaces
1148 *
1149 * task_xid_nr() : global id, i.e. the id seen from the init namespace;
1150 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of
1151 * current.
1152 * task_xid_nr_ns() : id seen from the ns specified;
1153 *
1154 * see also pid_nr() etc in include/linux/pid.h
1155 */
1156pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, struct pid_namespace *ns);
1157
1158static inline pid_t task_pid_nr(struct task_struct *tsk)
1159{
1160 return tsk->pid;
1161}
1162
1163static inline pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1164{
1165 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1166}
1167
1168static inline pid_t task_pid_vnr(struct task_struct *tsk)
1169{
1170 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1171}
1172
1173
1174static inline pid_t task_tgid_nr(struct task_struct *tsk)
1175{
1176 return tsk->tgid;
1177}
1178
1179/**
1180 * pid_alive - check that a task structure is not stale
1181 * @p: Task structure to be checked.
1182 *
1183 * Test if a process is not yet dead (at most zombie state)
1184 * If pid_alive fails, then pointers within the task structure
1185 * can be stale and must not be dereferenced.
1186 *
1187 * Return: 1 if the process is alive. 0 otherwise.
1188 */
1189static inline int pid_alive(const struct task_struct *p)
1190{
1191 return p->pids[PIDTYPE_PID].pid != NULL;
1192}
1193
1194static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1195{
1196 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1197}
1198
1199static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1200{
1201 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1202}
1203
1204
1205static inline pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1206{
1207 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1208}
1209
1210static inline pid_t task_session_vnr(struct task_struct *tsk)
1211{
1212 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1213}
1214
1215static inline pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1216{
1217 return __task_pid_nr_ns(tsk, __PIDTYPE_TGID, ns);
1218}
1219
1220static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1221{
1222 return __task_pid_nr_ns(tsk, __PIDTYPE_TGID, NULL);
1223}
1224
1225static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1226{
1227 pid_t pid = 0;
1228
1229 rcu_read_lock();
1230 if (pid_alive(tsk))
1231 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1232 rcu_read_unlock();
1233
1234 return pid;
1235}
1236
1237static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1238{
1239 return task_ppid_nr_ns(tsk, &init_pid_ns);
1240}
1241
1242/* Obsolete, do not use: */
1243static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1244{
1245 return task_pgrp_nr_ns(tsk, &init_pid_ns);
1246}
1247
1248#define TASK_REPORT_IDLE (TASK_REPORT + 1)
1249#define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1)
1250
1251static inline unsigned int task_state_index(struct task_struct *tsk)
1252{
1253 unsigned int tsk_state = READ_ONCE(tsk->state);
1254 unsigned int state = (tsk_state | tsk->exit_state) & TASK_REPORT;
1255
1256 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
1257
1258 if (tsk_state == TASK_IDLE)
1259 state = TASK_REPORT_IDLE;
1260
1261 return fls(state);
1262}
1263
1264static inline char task_index_to_char(unsigned int state)
1265{
1266 static const char state_char[] = "RSDTtXZPI";
1267
1268 BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1);
1269
1270 return state_char[state];
1271}
1272
1273static inline char task_state_to_char(struct task_struct *tsk)
1274{
1275 return task_index_to_char(task_state_index(tsk));
1276}
1277
1278/**
1279 * is_global_init - check if a task structure is init. Since init
1280 * is free to have sub-threads we need to check tgid.
1281 * @tsk: Task structure to be checked.
1282 *
1283 * Check if a task structure is the first user space task the kernel created.
1284 *
1285 * Return: 1 if the task structure is init. 0 otherwise.
1286 */
1287static inline int is_global_init(struct task_struct *tsk)
1288{
1289 return task_tgid_nr(tsk) == 1;
1290}
1291
1292extern struct pid *cad_pid;
1293
1294/*
1295 * Per process flags
1296 */
1297#define PF_IDLE 0x00000002 /* I am an IDLE thread */
1298#define PF_EXITING 0x00000004 /* Getting shut down */
1299#define PF_EXITPIDONE 0x00000008 /* PI exit done on shut down */
1300#define PF_VCPU 0x00000010 /* I'm a virtual CPU */
1301#define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */
1302#define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */
1303#define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */
1304#define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */
1305#define PF_DUMPCORE 0x00000200 /* Dumped core */
1306#define PF_SIGNALED 0x00000400 /* Killed by a signal */
1307#define PF_MEMALLOC 0x00000800 /* Allocating memory */
1308#define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */
1309#define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */
1310#define PF_USED_ASYNC 0x00004000 /* Used async_schedule*(), used by module init */
1311#define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */
1312#define PF_FROZEN 0x00010000 /* Frozen for system suspend */
1313#define PF_KSWAPD 0x00020000 /* I am kswapd */
1314#define PF_MEMALLOC_NOFS 0x00040000 /* All allocation requests will inherit GFP_NOFS */
1315#define PF_MEMALLOC_NOIO 0x00080000 /* All allocation requests will inherit GFP_NOIO */
1316#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
1317#define PF_KTHREAD 0x00200000 /* I am a kernel thread */
1318#define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */
1319#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1320#define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */
1321#define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
1322#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
1323#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */
1324#define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */
1325
1326/*
1327 * Only the _current_ task can read/write to tsk->flags, but other
1328 * tasks can access tsk->flags in readonly mode for example
1329 * with tsk_used_math (like during threaded core dumping).
1330 * There is however an exception to this rule during ptrace
1331 * or during fork: the ptracer task is allowed to write to the
1332 * child->flags of its traced child (same goes for fork, the parent
1333 * can write to the child->flags), because we're guaranteed the
1334 * child is not running and in turn not changing child->flags
1335 * at the same time the parent does it.
1336 */
1337#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1338#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1339#define clear_used_math() clear_stopped_child_used_math(current)
1340#define set_used_math() set_stopped_child_used_math(current)
1341
1342#define conditional_stopped_child_used_math(condition, child) \
1343 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1344
1345#define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current)
1346
1347#define copy_to_stopped_child_used_math(child) \
1348 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1349
1350/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1351#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1352#define used_math() tsk_used_math(current)
1353
1354static inline bool is_percpu_thread(void)
1355{
1356#ifdef CONFIG_SMP
1357 return (current->flags & PF_NO_SETAFFINITY) &&
1358 (current->nr_cpus_allowed == 1);
1359#else
1360 return true;
1361#endif
1362}
1363
1364/* Per-process atomic flags. */
1365#define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */
1366#define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */
1367#define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */
1368
1369
1370#define TASK_PFA_TEST(name, func) \
1371 static inline bool task_##func(struct task_struct *p) \
1372 { return test_bit(PFA_##name, &p->atomic_flags); }
1373
1374#define TASK_PFA_SET(name, func) \
1375 static inline void task_set_##func(struct task_struct *p) \
1376 { set_bit(PFA_##name, &p->atomic_flags); }
1377
1378#define TASK_PFA_CLEAR(name, func) \
1379 static inline void task_clear_##func(struct task_struct *p) \
1380 { clear_bit(PFA_##name, &p->atomic_flags); }
1381
1382TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1383TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1384
1385TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1386TASK_PFA_SET(SPREAD_PAGE, spread_page)
1387TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1388
1389TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1390TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1391TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1392
1393static inline void
1394current_restore_flags(unsigned long orig_flags, unsigned long flags)
1395{
1396 current->flags &= ~flags;
1397 current->flags |= orig_flags & flags;
1398}
1399
1400extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
1401extern int task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
1402#ifdef CONFIG_SMP
1403extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask);
1404extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
1405#else
1406static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
1407{
1408}
1409static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
1410{
1411 if (!cpumask_test_cpu(0, new_mask))
1412 return -EINVAL;
1413 return 0;
1414}
1415#endif
1416
1417#ifndef cpu_relax_yield
1418#define cpu_relax_yield() cpu_relax()
1419#endif
1420
1421extern int yield_to(struct task_struct *p, bool preempt);
1422extern void set_user_nice(struct task_struct *p, long nice);
1423extern int task_prio(const struct task_struct *p);
1424
1425/**
1426 * task_nice - return the nice value of a given task.
1427 * @p: the task in question.
1428 *
1429 * Return: The nice value [ -20 ... 0 ... 19 ].
1430 */
1431static inline int task_nice(const struct task_struct *p)
1432{
1433 return PRIO_TO_NICE((p)->static_prio);
1434}
1435
1436extern int can_nice(const struct task_struct *p, const int nice);
1437extern int task_curr(const struct task_struct *p);
1438extern int idle_cpu(int cpu);
1439extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
1440extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
1441extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1442extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
1443extern struct task_struct *idle_task(int cpu);
1444
1445/**
1446 * is_idle_task - is the specified task an idle task?
1447 * @p: the task in question.
1448 *
1449 * Return: 1 if @p is an idle task. 0 otherwise.
1450 */
1451static inline bool is_idle_task(const struct task_struct *p)
1452{
1453 return !!(p->flags & PF_IDLE);
1454}
1455
1456extern struct task_struct *curr_task(int cpu);
1457extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1458
1459void yield(void);
1460
1461union thread_union {
1462#ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK
1463 struct task_struct task;
1464#endif
1465#ifndef CONFIG_THREAD_INFO_IN_TASK
1466 struct thread_info thread_info;
1467#endif
1468 unsigned long stack[THREAD_SIZE/sizeof(long)];
1469};
1470
1471#ifndef CONFIG_THREAD_INFO_IN_TASK
1472extern struct thread_info init_thread_info;
1473#endif
1474
1475extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
1476
1477#ifdef CONFIG_THREAD_INFO_IN_TASK
1478static inline struct thread_info *task_thread_info(struct task_struct *task)
1479{
1480 return &task->thread_info;
1481}
1482#elif !defined(__HAVE_THREAD_FUNCTIONS)
1483# define task_thread_info(task) ((struct thread_info *)(task)->stack)
1484#endif
1485
1486/*
1487 * find a task by one of its numerical ids
1488 *
1489 * find_task_by_pid_ns():
1490 * finds a task by its pid in the specified namespace
1491 * find_task_by_vpid():
1492 * finds a task by its virtual pid
1493 *
1494 * see also find_vpid() etc in include/linux/pid.h
1495 */
1496
1497extern struct task_struct *find_task_by_vpid(pid_t nr);
1498extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
1499
1500/*
1501 * find a task by its virtual pid and get the task struct
1502 */
1503extern struct task_struct *find_get_task_by_vpid(pid_t nr);
1504
1505extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1506extern int wake_up_process(struct task_struct *tsk);
1507extern void wake_up_new_task(struct task_struct *tsk);
1508
1509#ifdef CONFIG_SMP
1510extern void kick_process(struct task_struct *tsk);
1511#else
1512static inline void kick_process(struct task_struct *tsk) { }
1513#endif
1514
1515extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
1516
1517static inline void set_task_comm(struct task_struct *tsk, const char *from)
1518{
1519 __set_task_comm(tsk, from, false);
1520}
1521
1522extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk);
1523#define get_task_comm(buf, tsk) ({ \
1524 BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN); \
1525 __get_task_comm(buf, sizeof(buf), tsk); \
1526})
1527
1528#ifdef CONFIG_SMP
1529void scheduler_ipi(void);
1530extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
1531#else
1532static inline void scheduler_ipi(void) { }
1533static inline unsigned long wait_task_inactive(struct task_struct *p, long match_state)
1534{
1535 return 1;
1536}
1537#endif
1538
1539/*
1540 * Set thread flags in other task's structures.
1541 * See asm/thread_info.h for TIF_xxxx flags available:
1542 */
1543static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1544{
1545 set_ti_thread_flag(task_thread_info(tsk), flag);
1546}
1547
1548static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1549{
1550 clear_ti_thread_flag(task_thread_info(tsk), flag);
1551}
1552
1553static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1554{
1555 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1556}
1557
1558static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1559{
1560 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1561}
1562
1563static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1564{
1565 return test_ti_thread_flag(task_thread_info(tsk), flag);
1566}
1567
1568static inline void set_tsk_need_resched(struct task_struct *tsk)
1569{
1570 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1571}
1572
1573static inline void clear_tsk_need_resched(struct task_struct *tsk)
1574{
1575 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1576}
1577
1578static inline int test_tsk_need_resched(struct task_struct *tsk)
1579{
1580 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
1581}
1582
1583/*
1584 * cond_resched() and cond_resched_lock(): latency reduction via
1585 * explicit rescheduling in places that are safe. The return
1586 * value indicates whether a reschedule was done in fact.
1587 * cond_resched_lock() will drop the spinlock before scheduling,
1588 * cond_resched_softirq() will enable bhs before scheduling.
1589 */
1590#ifndef CONFIG_PREEMPT
1591extern int _cond_resched(void);
1592#else
1593static inline int _cond_resched(void) { return 0; }
1594#endif
1595
1596#define cond_resched() ({ \
1597 ___might_sleep(__FILE__, __LINE__, 0); \
1598 _cond_resched(); \
1599})
1600
1601extern int __cond_resched_lock(spinlock_t *lock);
1602
1603#define cond_resched_lock(lock) ({ \
1604 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
1605 __cond_resched_lock(lock); \
1606})
1607
1608extern int __cond_resched_softirq(void);
1609
1610#define cond_resched_softirq() ({ \
1611 ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \
1612 __cond_resched_softirq(); \
1613})
1614
1615static inline void cond_resched_rcu(void)
1616{
1617#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
1618 rcu_read_unlock();
1619 cond_resched();
1620 rcu_read_lock();
1621#endif
1622}
1623
1624/*
1625 * Does a critical section need to be broken due to another
1626 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
1627 * but a general need for low latency)
1628 */
1629static inline int spin_needbreak(spinlock_t *lock)
1630{
1631#ifdef CONFIG_PREEMPT
1632 return spin_is_contended(lock);
1633#else
1634 return 0;
1635#endif
1636}
1637
1638static __always_inline bool need_resched(void)
1639{
1640 return unlikely(tif_need_resched());
1641}
1642
1643/*
1644 * Wrappers for p->thread_info->cpu access. No-op on UP.
1645 */
1646#ifdef CONFIG_SMP
1647
1648static inline unsigned int task_cpu(const struct task_struct *p)
1649{
1650#ifdef CONFIG_THREAD_INFO_IN_TASK
1651 return p->cpu;
1652#else
1653 return task_thread_info(p)->cpu;
1654#endif
1655}
1656
1657extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
1658
1659#else
1660
1661static inline unsigned int task_cpu(const struct task_struct *p)
1662{
1663 return 0;
1664}
1665
1666static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1667{
1668}
1669
1670#endif /* CONFIG_SMP */
1671
1672/*
1673 * In order to reduce various lock holder preemption latencies provide an
1674 * interface to see if a vCPU is currently running or not.
1675 *
1676 * This allows us to terminate optimistic spin loops and block, analogous to
1677 * the native optimistic spin heuristic of testing if the lock owner task is
1678 * running or not.
1679 */
1680#ifndef vcpu_is_preempted
1681# define vcpu_is_preempted(cpu) false
1682#endif
1683
1684extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
1685extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
1686
1687#ifndef TASK_SIZE_OF
1688#define TASK_SIZE_OF(tsk) TASK_SIZE
1689#endif
1690
1691#endif
1692