1 /* SPDX-License-Identifier: GPL-2.0 */
6 * Define 'struct task_struct' and provide the main scheduler
7 * APIs (schedule(), wakeup variants, etc.)
10 #include <uapi/linux/sched.h>
12 #include <asm/current.h>
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/refcount.h>
25 #include <linux/resource.h>
26 #include <linux/latencytop.h>
27 #include <linux/sched/prio.h>
28 #include <linux/sched/types.h>
29 #include <linux/signal_types.h>
30 #include <linux/mm_types_task.h>
31 #include <linux/task_io_accounting.h>
32 #include <linux/posix-timers.h>
33 #include <linux/rseq.h>
35 /* task_struct member predeclarations (sorted alphabetically): */
37 struct backing_dev_info;
40 struct capture_control;
43 struct futex_pi_state;
48 struct perf_event_context;
50 struct pipe_inode_info;
53 struct robust_list_head;
59 struct sighand_struct;
61 struct task_delay_info;
65 * Task state bitmask. NOTE! These bits are also
66 * encoded in fs/proc/array.c: get_task_state().
68 * We have two separate sets of flags: task->state
69 * is about runnability, while task->exit_state are
70 * about the task exiting. Confusing, but this way
71 * modifying one set can't modify the other one by
75 /* Used in tsk->state: */
76 #define TASK_RUNNING 0x0000
77 #define TASK_INTERRUPTIBLE 0x0001
78 #define TASK_UNINTERRUPTIBLE 0x0002
79 #define __TASK_STOPPED 0x0004
80 #define __TASK_TRACED 0x0008
81 /* Used in tsk->exit_state: */
82 #define EXIT_DEAD 0x0010
83 #define EXIT_ZOMBIE 0x0020
84 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD)
85 /* Used in tsk->state again: */
86 #define TASK_PARKED 0x0040
87 #define TASK_DEAD 0x0080
88 #define TASK_WAKEKILL 0x0100
89 #define TASK_WAKING 0x0200
90 #define TASK_NOLOAD 0x0400
91 #define TASK_NEW 0x0800
92 #define TASK_STATE_MAX 0x1000
94 /* Convenience macros for the sake of set_current_state: */
95 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
96 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
97 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED)
99 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
101 /* Convenience macros for the sake of wake_up(): */
102 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
104 /* get_task_state(): */
105 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \
106 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
107 __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \
110 #define task_is_traced(task) ((task->state & __TASK_TRACED) != 0)
112 #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0)
114 #define task_is_stopped_or_traced(task) ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
116 #define task_contributes_to_load(task) ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
117 (task->flags & PF_FROZEN) == 0 && \
118 (task->state & TASK_NOLOAD) == 0)
120 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
123 * Special states are those that do not use the normal wait-loop pattern. See
124 * the comment with set_special_state().
126 #define is_special_task_state(state) \
127 ((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD))
129 #define __set_current_state(state_value) \
131 WARN_ON_ONCE(is_special_task_state(state_value));\
132 current->task_state_change = _THIS_IP_; \
133 current->state = (state_value); \
136 #define set_current_state(state_value) \
138 WARN_ON_ONCE(is_special_task_state(state_value));\
139 current->task_state_change = _THIS_IP_; \
140 smp_store_mb(current->state, (state_value)); \
143 #define set_special_state(state_value) \
145 unsigned long flags; /* may shadow */ \
146 WARN_ON_ONCE(!is_special_task_state(state_value)); \
147 raw_spin_lock_irqsave(¤t->pi_lock, flags); \
148 current->task_state_change = _THIS_IP_; \
149 current->state = (state_value); \
150 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \
154 * set_current_state() includes a barrier so that the write of current->state
155 * is correctly serialised wrt the caller's subsequent test of whether to
159 * set_current_state(TASK_UNINTERRUPTIBLE);
165 * __set_current_state(TASK_RUNNING);
167 * If the caller does not need such serialisation (because, for instance, the
168 * condition test and condition change and wakeup are under the same lock) then
169 * use __set_current_state().
171 * The above is typically ordered against the wakeup, which does:
173 * need_sleep = false;
174 * wake_up_state(p, TASK_UNINTERRUPTIBLE);
176 * where wake_up_state() executes a full memory barrier before accessing the
179 * Wakeup will do: if (@state & p->state) p->state = TASK_RUNNING, that is,
180 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
181 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING).
183 * However, with slightly different timing the wakeup TASK_RUNNING store can
184 * also collide with the TASK_UNINTERRUPTIBLE store. Losing that store is not
185 * a problem either because that will result in one extra go around the loop
186 * and our @cond test will save the day.
188 * Also see the comments of try_to_wake_up().
190 #define __set_current_state(state_value) \
191 current->state = (state_value)
193 #define set_current_state(state_value) \
194 smp_store_mb(current->state, (state_value))
197 * set_special_state() should be used for those states when the blocking task
198 * can not use the regular condition based wait-loop. In that case we must
199 * serialize against wakeups such that any possible in-flight TASK_RUNNING stores
200 * will not collide with our state change.
202 #define set_special_state(state_value) \
204 unsigned long flags; /* may shadow */ \
205 raw_spin_lock_irqsave(¤t->pi_lock, flags); \
206 current->state = (state_value); \
207 raw_spin_unlock_irqrestore(¤t->pi_lock, flags); \
212 /* Task command name length: */
213 #define TASK_COMM_LEN 16
215 extern void scheduler_tick(void);
217 #define MAX_SCHEDULE_TIMEOUT LONG_MAX
219 extern long schedule_timeout(long timeout);
220 extern long schedule_timeout_interruptible(long timeout);
221 extern long schedule_timeout_killable(long timeout);
222 extern long schedule_timeout_uninterruptible(long timeout);
223 extern long schedule_timeout_idle(long timeout);
224 asmlinkage void schedule(void);
225 extern void schedule_preempt_disabled(void);
226 asmlinkage void preempt_schedule_irq(void);
228 extern int __must_check io_schedule_prepare(void);
229 extern void io_schedule_finish(int token);
230 extern long io_schedule_timeout(long timeout);
231 extern void io_schedule(void);
234 * struct prev_cputime - snapshot of system and user cputime
235 * @utime: time spent in user mode
236 * @stime: time spent in system mode
237 * @lock: protects the above two fields
239 * Stores previous user/system time values such that we can guarantee
242 struct prev_cputime {
243 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
251 /* Task is sleeping or running in a CPU with VTIME inactive: */
255 /* Task runs in kernelspace in a CPU with VTIME active: */
257 /* Task runs in userspace in a CPU with VTIME active: */
259 /* Task runs as guests in a CPU with VTIME active: */
265 unsigned long long starttime;
266 enum vtime_state state;
274 * Utilization clamp constraints.
275 * @UCLAMP_MIN: Minimum utilization
276 * @UCLAMP_MAX: Maximum utilization
277 * @UCLAMP_CNT: Utilization clamp constraints count
286 extern struct root_domain def_root_domain;
287 extern struct mutex sched_domains_mutex;
291 #ifdef CONFIG_SCHED_INFO
292 /* Cumulative counters: */
294 /* # of times we have run on this CPU: */
295 unsigned long pcount;
297 /* Time spent waiting on a runqueue: */
298 unsigned long long run_delay;
302 /* When did we last run on a CPU? */
303 unsigned long long last_arrival;
305 /* When were we last queued to run? */
306 unsigned long long last_queued;
308 #endif /* CONFIG_SCHED_INFO */
312 * Integer metrics need fixed point arithmetic, e.g., sched/fair
313 * has a few: load, load_avg, util_avg, freq, and capacity.
315 * We define a basic fixed point arithmetic range, and then formalize
316 * all these metrics based on that basic range.
318 # define SCHED_FIXEDPOINT_SHIFT 10
319 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT)
321 /* Increase resolution of cpu_capacity calculations */
322 # define SCHED_CAPACITY_SHIFT SCHED_FIXEDPOINT_SHIFT
323 # define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT)
326 unsigned long weight;
331 * struct util_est - Estimation utilization of FAIR tasks
332 * @enqueued: instantaneous estimated utilization of a task/cpu
333 * @ewma: the Exponential Weighted Moving Average (EWMA)
334 * utilization of a task
336 * Support data structure to track an Exponential Weighted Moving Average
337 * (EWMA) of a FAIR task's utilization. New samples are added to the moving
338 * average each time a task completes an activation. Sample's weight is chosen
339 * so that the EWMA will be relatively insensitive to transient changes to the
342 * The enqueued attribute has a slightly different meaning for tasks and cpus:
343 * - task: the task's util_avg at last task dequeue time
344 * - cfs_rq: the sum of util_est.enqueued for each RUNNABLE task on that CPU
345 * Thus, the util_est.enqueued of a task represents the contribution on the
346 * estimated utilization of the CPU where that task is currently enqueued.
348 * Only for tasks we track a moving average of the past instantaneous
349 * estimated utilization. This allows to absorb sporadic drops in utilization
350 * of an otherwise almost periodic task.
353 unsigned int enqueued;
355 #define UTIL_EST_WEIGHT_SHIFT 2
356 } __attribute__((__aligned__(sizeof(u64))));
359 * The load/runnable/util_avg accumulates an infinite geometric series
360 * (see __update_load_avg_cfs_rq() in kernel/sched/pelt.c).
362 * [load_avg definition]
364 * load_avg = runnable% * scale_load_down(load)
366 * [runnable_avg definition]
368 * runnable_avg = runnable% * SCHED_CAPACITY_SCALE
370 * [util_avg definition]
372 * util_avg = running% * SCHED_CAPACITY_SCALE
374 * where runnable% is the time ratio that a sched_entity is runnable and
375 * running% the time ratio that a sched_entity is running.
377 * For cfs_rq, they are the aggregated values of all runnable and blocked
380 * The load/runnable/util_avg doesn't direcly factor frequency scaling and CPU
381 * capacity scaling. The scaling is done through the rq_clock_pelt that is used
382 * for computing those signals (see update_rq_clock_pelt())
384 * N.B., the above ratios (runnable% and running%) themselves are in the
385 * range of [0, 1]. To do fixed point arithmetics, we therefore scale them
386 * to as large a range as necessary. This is for example reflected by
387 * util_avg's SCHED_CAPACITY_SCALE.
391 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
392 * with the highest load (=88761), always runnable on a single cfs_rq,
393 * and should not overflow as the number already hits PID_MAX_LIMIT.
395 * For all other cases (including 32-bit kernels), struct load_weight's
396 * weight will overflow first before we do, because:
398 * Max(load_avg) <= Max(load.weight)
400 * Then it is the load_weight's responsibility to consider overflow
404 u64 last_update_time;
409 unsigned long load_avg;
410 unsigned long runnable_avg;
411 unsigned long util_avg;
412 struct util_est util_est;
413 } ____cacheline_aligned;
415 struct sched_statistics {
416 #ifdef CONFIG_SCHEDSTATS
426 s64 sum_sleep_runtime;
433 u64 nr_migrations_cold;
434 u64 nr_failed_migrations_affine;
435 u64 nr_failed_migrations_running;
436 u64 nr_failed_migrations_hot;
437 u64 nr_forced_migrations;
441 u64 nr_wakeups_migrate;
442 u64 nr_wakeups_local;
443 u64 nr_wakeups_remote;
444 u64 nr_wakeups_affine;
445 u64 nr_wakeups_affine_attempts;
446 u64 nr_wakeups_passive;
451 struct sched_entity {
452 /* For load-balancing: */
453 struct load_weight load;
454 struct rb_node run_node;
455 struct list_head group_node;
459 u64 sum_exec_runtime;
461 u64 prev_sum_exec_runtime;
465 struct sched_statistics statistics;
467 #ifdef CONFIG_FAIR_GROUP_SCHED
469 struct sched_entity *parent;
470 /* rq on which this entity is (to be) queued: */
471 struct cfs_rq *cfs_rq;
472 /* rq "owned" by this entity/group: */
474 /* cached value of my_q->h_nr_running */
475 unsigned long runnable_weight;
480 * Per entity load average tracking.
482 * Put into separate cache line so it does not
483 * collide with read-mostly values above.
485 struct sched_avg avg;
489 struct sched_rt_entity {
490 struct list_head run_list;
491 unsigned long timeout;
492 unsigned long watchdog_stamp;
493 unsigned int time_slice;
494 unsigned short on_rq;
495 unsigned short on_list;
497 struct sched_rt_entity *back;
498 #ifdef CONFIG_RT_GROUP_SCHED
499 struct sched_rt_entity *parent;
500 /* rq on which this entity is (to be) queued: */
502 /* rq "owned" by this entity/group: */
505 } __randomize_layout;
507 struct sched_dl_entity {
508 struct rb_node rb_node;
511 * Original scheduling parameters. Copied here from sched_attr
512 * during sched_setattr(), they will remain the same until
513 * the next sched_setattr().
515 u64 dl_runtime; /* Maximum runtime for each instance */
516 u64 dl_deadline; /* Relative deadline of each instance */
517 u64 dl_period; /* Separation of two instances (period) */
518 u64 dl_bw; /* dl_runtime / dl_period */
519 u64 dl_density; /* dl_runtime / dl_deadline */
522 * Actual scheduling parameters. Initialized with the values above,
523 * they are continuously updated during task execution. Note that
524 * the remaining runtime could be < 0 in case we are in overrun.
526 s64 runtime; /* Remaining runtime for this instance */
527 u64 deadline; /* Absolute deadline for this instance */
528 unsigned int flags; /* Specifying the scheduler behaviour */
533 * @dl_throttled tells if we exhausted the runtime. If so, the
534 * task has to wait for a replenishment to be performed at the
535 * next firing of dl_timer.
537 * @dl_boosted tells if we are boosted due to DI. If so we are
538 * outside bandwidth enforcement mechanism (but only until we
539 * exit the critical section);
541 * @dl_yielded tells if task gave up the CPU before consuming
542 * all its available runtime during the last job.
544 * @dl_non_contending tells if the task is inactive while still
545 * contributing to the active utilization. In other words, it
546 * indicates if the inactive timer has been armed and its handler
547 * has not been executed yet. This flag is useful to avoid race
548 * conditions between the inactive timer handler and the wakeup
551 * @dl_overrun tells if the task asked to be informed about runtime
554 unsigned int dl_throttled : 1;
555 unsigned int dl_boosted : 1;
556 unsigned int dl_yielded : 1;
557 unsigned int dl_non_contending : 1;
558 unsigned int dl_overrun : 1;
561 * Bandwidth enforcement timer. Each -deadline task has its
562 * own bandwidth to be enforced, thus we need one timer per task.
564 struct hrtimer dl_timer;
567 * Inactive timer, responsible for decreasing the active utilization
568 * at the "0-lag time". When a -deadline task blocks, it contributes
569 * to GRUB's active utilization until the "0-lag time", hence a
570 * timer is needed to decrease the active utilization at the correct
573 struct hrtimer inactive_timer;
576 #ifdef CONFIG_UCLAMP_TASK
577 /* Number of utilization clamp buckets (shorter alias) */
578 #define UCLAMP_BUCKETS CONFIG_UCLAMP_BUCKETS_COUNT
581 * Utilization clamp for a scheduling entity
582 * @value: clamp value "assigned" to a se
583 * @bucket_id: bucket index corresponding to the "assigned" value
584 * @active: the se is currently refcounted in a rq's bucket
585 * @user_defined: the requested clamp value comes from user-space
587 * The bucket_id is the index of the clamp bucket matching the clamp value
588 * which is pre-computed and stored to avoid expensive integer divisions from
591 * The active bit is set whenever a task has got an "effective" value assigned,
592 * which can be different from the clamp value "requested" from user-space.
593 * This allows to know a task is refcounted in the rq's bucket corresponding
594 * to the "effective" bucket_id.
596 * The user_defined bit is set whenever a task has got a task-specific clamp
597 * value requested from userspace, i.e. the system defaults apply to this task
598 * just as a restriction. This allows to relax default clamps when a less
599 * restrictive task-specific value has been requested, thus allowing to
600 * implement a "nice" semantic. For example, a task running with a 20%
601 * default boost can still drop its own boosting to 0%.
604 unsigned int value : bits_per(SCHED_CAPACITY_SCALE);
605 unsigned int bucket_id : bits_per(UCLAMP_BUCKETS);
606 unsigned int active : 1;
607 unsigned int user_defined : 1;
609 #endif /* CONFIG_UCLAMP_TASK */
615 u8 exp_hint; /* Hint for performance. */
616 u8 need_mb; /* Readers need smp_mb(). */
618 u32 s; /* Set of bits. */
621 enum perf_event_task_context {
622 perf_invalid_context = -1,
625 perf_nr_task_contexts,
629 struct wake_q_node *next;
633 #ifdef CONFIG_THREAD_INFO_IN_TASK
635 * For reasons of header soup (see current_thread_info()), this
636 * must be the first element of task_struct.
638 struct thread_info thread_info;
640 /* -1 unrunnable, 0 runnable, >0 stopped: */
644 * This begins the randomizable portion of task_struct. Only
645 * scheduling-critical items should be added above here.
647 randomized_struct_fields_start
651 /* Per task flags (PF_*), defined further below: */
656 struct llist_node wake_entry;
658 #ifdef CONFIG_THREAD_INFO_IN_TASK
662 unsigned int wakee_flips;
663 unsigned long wakee_flip_decay_ts;
664 struct task_struct *last_wakee;
667 * recent_used_cpu is initially set as the last CPU used by a task
668 * that wakes affine another task. Waker/wakee relationships can
669 * push tasks around a CPU where each wakeup moves to the next one.
670 * Tracking a recently used CPU allows a quick search for a recently
671 * used CPU that may be idle.
681 unsigned int rt_priority;
683 const struct sched_class *sched_class;
684 struct sched_entity se;
685 struct sched_rt_entity rt;
686 #ifdef CONFIG_CGROUP_SCHED
687 struct task_group *sched_task_group;
689 struct sched_dl_entity dl;
691 #ifdef CONFIG_UCLAMP_TASK
692 /* Clamp values requested for a scheduling entity */
693 struct uclamp_se uclamp_req[UCLAMP_CNT];
694 /* Effective clamp values used for a scheduling entity */
695 struct uclamp_se uclamp[UCLAMP_CNT];
698 #ifdef CONFIG_PREEMPT_NOTIFIERS
699 /* List of struct preempt_notifier: */
700 struct hlist_head preempt_notifiers;
703 #ifdef CONFIG_BLK_DEV_IO_TRACE
704 unsigned int btrace_seq;
709 const cpumask_t *cpus_ptr;
712 #ifdef CONFIG_PREEMPT_RCU
713 int rcu_read_lock_nesting;
714 union rcu_special rcu_read_unlock_special;
715 struct list_head rcu_node_entry;
716 struct rcu_node *rcu_blocked_node;
717 #endif /* #ifdef CONFIG_PREEMPT_RCU */
719 #ifdef CONFIG_TASKS_RCU
720 unsigned long rcu_tasks_nvcsw;
721 u8 rcu_tasks_holdout;
723 int rcu_tasks_idle_cpu;
724 struct list_head rcu_tasks_holdout_list;
725 #endif /* #ifdef CONFIG_TASKS_RCU */
727 #ifdef CONFIG_TASKS_TRACE_RCU
728 int trc_reader_nesting;
730 union rcu_special trc_reader_special;
731 bool trc_reader_checked;
732 struct list_head trc_holdout_list;
733 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */
735 struct sched_info sched_info;
737 struct list_head tasks;
739 struct plist_node pushable_tasks;
740 struct rb_node pushable_dl_tasks;
743 struct mm_struct *mm;
744 struct mm_struct *active_mm;
746 /* Per-thread vma caching: */
747 struct vmacache vmacache;
749 #ifdef SPLIT_RSS_COUNTING
750 struct task_rss_stat rss_stat;
755 /* The signal sent when the parent dies: */
757 /* JOBCTL_*, siglock protected: */
758 unsigned long jobctl;
760 /* Used for emulating ABI behavior of previous Linux versions: */
761 unsigned int personality;
763 /* Scheduler bits, serialized by scheduler locks: */
764 unsigned sched_reset_on_fork:1;
765 unsigned sched_contributes_to_load:1;
766 unsigned sched_migrated:1;
767 unsigned sched_remote_wakeup:1;
769 unsigned sched_psi_wake_requeue:1;
772 /* Force alignment to the next boundary: */
775 /* Unserialized, strictly 'current' */
777 /* Bit to tell LSMs we're in execve(): */
778 unsigned in_execve:1;
779 unsigned in_iowait:1;
780 #ifndef TIF_RESTORE_SIGMASK
781 unsigned restore_sigmask:1;
784 unsigned in_user_fault:1;
786 #ifdef CONFIG_COMPAT_BRK
787 unsigned brk_randomized:1;
789 #ifdef CONFIG_CGROUPS
790 /* disallow userland-initiated cgroup migration */
791 unsigned no_cgroup_migration:1;
792 /* task is frozen/stopped (used by the cgroup freezer) */
795 #ifdef CONFIG_BLK_CGROUP
796 unsigned use_memdelay:1;
799 /* Stalled due to lack of memory */
800 unsigned in_memstall:1;
803 unsigned long atomic_flags; /* Flags requiring atomic access. */
805 struct restart_block restart_block;
810 #ifdef CONFIG_STACKPROTECTOR
811 /* Canary value for the -fstack-protector GCC feature: */
812 unsigned long stack_canary;
815 * Pointers to the (original) parent process, youngest child, younger sibling,
816 * older sibling, respectively. (p->father can be replaced with
817 * p->real_parent->pid)
820 /* Real parent process: */
821 struct task_struct __rcu *real_parent;
823 /* Recipient of SIGCHLD, wait4() reports: */
824 struct task_struct __rcu *parent;
827 * Children/sibling form the list of natural children:
829 struct list_head children;
830 struct list_head sibling;
831 struct task_struct *group_leader;
834 * 'ptraced' is the list of tasks this task is using ptrace() on.
836 * This includes both natural children and PTRACE_ATTACH targets.
837 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
839 struct list_head ptraced;
840 struct list_head ptrace_entry;
842 /* PID/PID hash table linkage. */
843 struct pid *thread_pid;
844 struct hlist_node pid_links[PIDTYPE_MAX];
845 struct list_head thread_group;
846 struct list_head thread_node;
848 struct completion *vfork_done;
850 /* CLONE_CHILD_SETTID: */
851 int __user *set_child_tid;
853 /* CLONE_CHILD_CLEARTID: */
854 int __user *clear_child_tid;
858 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
863 struct prev_cputime prev_cputime;
864 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
868 #ifdef CONFIG_NO_HZ_FULL
869 atomic_t tick_dep_mask;
871 /* Context switch counts: */
873 unsigned long nivcsw;
875 /* Monotonic time in nsecs: */
878 /* Boot based time in nsecs: */
881 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
882 unsigned long min_flt;
883 unsigned long maj_flt;
885 /* Empty if CONFIG_POSIX_CPUTIMERS=n */
886 struct posix_cputimers posix_cputimers;
888 /* Process credentials: */
890 /* Tracer's credentials at attach: */
891 const struct cred __rcu *ptracer_cred;
893 /* Objective and real subjective task credentials (COW): */
894 const struct cred __rcu *real_cred;
896 /* Effective (overridable) subjective task credentials (COW): */
897 const struct cred __rcu *cred;
900 /* Cached requested key. */
901 struct key *cached_requested_key;
905 * executable name, excluding path.
907 * - normally initialized setup_new_exec()
908 * - access it with [gs]et_task_comm()
909 * - lock it with task_lock()
911 char comm[TASK_COMM_LEN];
913 struct nameidata *nameidata;
915 #ifdef CONFIG_SYSVIPC
916 struct sysv_sem sysvsem;
917 struct sysv_shm sysvshm;
919 #ifdef CONFIG_DETECT_HUNG_TASK
920 unsigned long last_switch_count;
921 unsigned long last_switch_time;
923 /* Filesystem information: */
924 struct fs_struct *fs;
926 /* Open file information: */
927 struct files_struct *files;
930 struct nsproxy *nsproxy;
932 /* Signal handlers: */
933 struct signal_struct *signal;
934 struct sighand_struct __rcu *sighand;
936 sigset_t real_blocked;
937 /* Restored if set_restore_sigmask() was used: */
938 sigset_t saved_sigmask;
939 struct sigpending pending;
940 unsigned long sas_ss_sp;
942 unsigned int sas_ss_flags;
944 struct callback_head *task_works;
947 #ifdef CONFIG_AUDITSYSCALL
948 struct audit_context *audit_context;
951 unsigned int sessionid;
953 struct seccomp seccomp;
955 /* Thread group tracking: */
959 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
960 spinlock_t alloc_lock;
962 /* Protection of the PI data structures: */
963 raw_spinlock_t pi_lock;
965 struct wake_q_node wake_q;
967 #ifdef CONFIG_RT_MUTEXES
968 /* PI waiters blocked on a rt_mutex held by this task: */
969 struct rb_root_cached pi_waiters;
970 /* Updated under owner's pi_lock and rq lock */
971 struct task_struct *pi_top_task;
972 /* Deadlock detection and priority inheritance handling: */
973 struct rt_mutex_waiter *pi_blocked_on;
976 #ifdef CONFIG_DEBUG_MUTEXES
977 /* Mutex deadlock detection: */
978 struct mutex_waiter *blocked_on;
981 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
985 #ifdef CONFIG_TRACE_IRQFLAGS
986 unsigned int irq_events;
987 unsigned int hardirq_threaded;
988 unsigned long hardirq_enable_ip;
989 unsigned long hardirq_disable_ip;
990 unsigned int hardirq_enable_event;
991 unsigned int hardirq_disable_event;
992 int hardirqs_enabled;
994 unsigned long softirq_disable_ip;
995 unsigned long softirq_enable_ip;
996 unsigned int softirq_disable_event;
997 unsigned int softirq_enable_event;
998 int softirqs_enabled;
1003 #ifdef CONFIG_LOCKDEP
1004 # define MAX_LOCK_DEPTH 48UL
1007 unsigned int lockdep_recursion;
1008 struct held_lock held_locks[MAX_LOCK_DEPTH];
1012 unsigned int in_ubsan;
1015 /* Journalling filesystem info: */
1018 /* Stacked block device info: */
1019 struct bio_list *bio_list;
1022 /* Stack plugging: */
1023 struct blk_plug *plug;
1027 struct reclaim_state *reclaim_state;
1029 struct backing_dev_info *backing_dev_info;
1031 struct io_context *io_context;
1033 #ifdef CONFIG_COMPACTION
1034 struct capture_control *capture_control;
1037 unsigned long ptrace_message;
1038 kernel_siginfo_t *last_siginfo;
1040 struct task_io_accounting ioac;
1042 /* Pressure stall state */
1043 unsigned int psi_flags;
1045 #ifdef CONFIG_TASK_XACCT
1046 /* Accumulated RSS usage: */
1048 /* Accumulated virtual memory usage: */
1050 /* stime + utime since last update: */
1053 #ifdef CONFIG_CPUSETS
1054 /* Protected by ->alloc_lock: */
1055 nodemask_t mems_allowed;
1056 /* Seqence number to catch updates: */
1057 seqcount_t mems_allowed_seq;
1058 int cpuset_mem_spread_rotor;
1059 int cpuset_slab_spread_rotor;
1061 #ifdef CONFIG_CGROUPS
1062 /* Control Group info protected by css_set_lock: */
1063 struct css_set __rcu *cgroups;
1064 /* cg_list protected by css_set_lock and tsk->alloc_lock: */
1065 struct list_head cg_list;
1067 #ifdef CONFIG_X86_CPU_RESCTRL
1072 struct robust_list_head __user *robust_list;
1073 #ifdef CONFIG_COMPAT
1074 struct compat_robust_list_head __user *compat_robust_list;
1076 struct list_head pi_state_list;
1077 struct futex_pi_state *pi_state_cache;
1078 struct mutex futex_exit_mutex;
1079 unsigned int futex_state;
1081 #ifdef CONFIG_PERF_EVENTS
1082 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1083 struct mutex perf_event_mutex;
1084 struct list_head perf_event_list;
1086 #ifdef CONFIG_DEBUG_PREEMPT
1087 unsigned long preempt_disable_ip;
1090 /* Protected by alloc_lock: */
1091 struct mempolicy *mempolicy;
1093 short pref_node_fork;
1095 #ifdef CONFIG_NUMA_BALANCING
1097 unsigned int numa_scan_period;
1098 unsigned int numa_scan_period_max;
1099 int numa_preferred_nid;
1100 unsigned long numa_migrate_retry;
1101 /* Migration stamp: */
1103 u64 last_task_numa_placement;
1104 u64 last_sum_exec_runtime;
1105 struct callback_head numa_work;
1108 * This pointer is only modified for current in syscall and
1109 * pagefault context (and for tasks being destroyed), so it can be read
1110 * from any of the following contexts:
1111 * - RCU read-side critical section
1112 * - current->numa_group from everywhere
1113 * - task's runqueue locked, task not running
1115 struct numa_group __rcu *numa_group;
1118 * numa_faults is an array split into four regions:
1119 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1120 * in this precise order.
1122 * faults_memory: Exponential decaying average of faults on a per-node
1123 * basis. Scheduling placement decisions are made based on these
1124 * counts. The values remain static for the duration of a PTE scan.
1125 * faults_cpu: Track the nodes the process was running on when a NUMA
1126 * hinting fault was incurred.
1127 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1128 * during the current scan window. When the scan completes, the counts
1129 * in faults_memory and faults_cpu decay and these values are copied.
1131 unsigned long *numa_faults;
1132 unsigned long total_numa_faults;
1135 * numa_faults_locality tracks if faults recorded during the last
1136 * scan window were remote/local or failed to migrate. The task scan
1137 * period is adapted based on the locality of the faults with different
1138 * weights depending on whether they were shared or private faults
1140 unsigned long numa_faults_locality[3];
1142 unsigned long numa_pages_migrated;
1143 #endif /* CONFIG_NUMA_BALANCING */
1146 struct rseq __user *rseq;
1149 * RmW on rseq_event_mask must be performed atomically
1150 * with respect to preemption.
1152 unsigned long rseq_event_mask;
1155 struct tlbflush_unmap_batch tlb_ubc;
1158 refcount_t rcu_users;
1159 struct rcu_head rcu;
1162 /* Cache last used pipe for splice(): */
1163 struct pipe_inode_info *splice_pipe;
1165 struct page_frag task_frag;
1167 #ifdef CONFIG_TASK_DELAY_ACCT
1168 struct task_delay_info *delays;
1171 #ifdef CONFIG_FAULT_INJECTION
1173 unsigned int fail_nth;
1176 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1177 * balance_dirty_pages() for a dirty throttling pause:
1180 int nr_dirtied_pause;
1181 /* Start of a write-and-pause period: */
1182 unsigned long dirty_paused_when;
1184 #ifdef CONFIG_LATENCYTOP
1185 int latency_record_count;
1186 struct latency_record latency_record[LT_SAVECOUNT];
1189 * Time slack values; these are used to round up poll() and
1190 * select() etc timeout values. These are in nanoseconds.
1193 u64 default_timer_slack_ns;
1196 unsigned int kasan_depth;
1199 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1200 /* Index of current stored address in ret_stack: */
1204 /* Stack of return addresses for return function tracing: */
1205 struct ftrace_ret_stack *ret_stack;
1207 /* Timestamp for last schedule: */
1208 unsigned long long ftrace_timestamp;
1211 * Number of functions that haven't been traced
1212 * because of depth overrun:
1214 atomic_t trace_overrun;
1216 /* Pause tracing: */
1217 atomic_t tracing_graph_pause;
1220 #ifdef CONFIG_TRACING
1221 /* State flags for use by tracers: */
1222 unsigned long trace;
1224 /* Bitmask and counter of trace recursion: */
1225 unsigned long trace_recursion;
1226 #endif /* CONFIG_TRACING */
1229 /* See kernel/kcov.c for more details. */
1231 /* Coverage collection mode enabled for this task (0 if disabled): */
1232 unsigned int kcov_mode;
1234 /* Size of the kcov_area: */
1235 unsigned int kcov_size;
1237 /* Buffer for coverage collection: */
1240 /* KCOV descriptor wired with this task or NULL: */
1243 /* KCOV common handle for remote coverage collection: */
1246 /* KCOV sequence number: */
1251 struct mem_cgroup *memcg_in_oom;
1252 gfp_t memcg_oom_gfp_mask;
1253 int memcg_oom_order;
1255 /* Number of pages to reclaim on returning to userland: */
1256 unsigned int memcg_nr_pages_over_high;
1258 /* Used by memcontrol for targeted memcg charge: */
1259 struct mem_cgroup *active_memcg;
1262 #ifdef CONFIG_BLK_CGROUP
1263 struct request_queue *throttle_queue;
1266 #ifdef CONFIG_UPROBES
1267 struct uprobe_task *utask;
1269 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1270 unsigned int sequential_io;
1271 unsigned int sequential_io_avg;
1273 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1274 unsigned long task_state_change;
1276 int pagefault_disabled;
1278 struct task_struct *oom_reaper_list;
1280 #ifdef CONFIG_VMAP_STACK
1281 struct vm_struct *stack_vm_area;
1283 #ifdef CONFIG_THREAD_INFO_IN_TASK
1284 /* A live task holds one reference: */
1285 refcount_t stack_refcount;
1287 #ifdef CONFIG_LIVEPATCH
1290 #ifdef CONFIG_SECURITY
1291 /* Used by LSM modules for access restriction: */
1295 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK
1296 unsigned long lowest_stack;
1297 unsigned long prev_lowest_stack;
1301 * New fields for task_struct should be added above here, so that
1302 * they are included in the randomized portion of task_struct.
1304 randomized_struct_fields_end
1306 /* CPU-specific state of this task: */
1307 struct thread_struct thread;
1310 * WARNING: on x86, 'thread_struct' contains a variable-sized
1311 * structure. It *MUST* be at the end of 'task_struct'.
1313 * Do not put anything below here!
1317 static inline struct pid *task_pid(struct task_struct *task)
1319 return task->thread_pid;
1323 * the helpers to get the task's different pids as they are seen
1324 * from various namespaces
1326 * task_xid_nr() : global id, i.e. the id seen from the init namespace;
1327 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of
1329 * task_xid_nr_ns() : id seen from the ns specified;
1331 * see also pid_nr() etc in include/linux/pid.h
1333 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type, struct pid_namespace *ns);
1335 static inline pid_t task_pid_nr(struct task_struct *tsk)
1340 static inline pid_t task_pid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1342 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1345 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1347 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1351 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1357 * pid_alive - check that a task structure is not stale
1358 * @p: Task structure to be checked.
1360 * Test if a process is not yet dead (at most zombie state)
1361 * If pid_alive fails, then pointers within the task structure
1362 * can be stale and must not be dereferenced.
1364 * Return: 1 if the process is alive. 0 otherwise.
1366 static inline int pid_alive(const struct task_struct *p)
1368 return p->thread_pid != NULL;
1371 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1373 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1376 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1378 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1382 static inline pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1384 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1387 static inline pid_t task_session_vnr(struct task_struct *tsk)
1389 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1392 static inline pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns)
1394 return __task_pid_nr_ns(tsk, PIDTYPE_TGID, ns);
1397 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1399 return __task_pid_nr_ns(tsk, PIDTYPE_TGID, NULL);
1402 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1408 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1414 static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1416 return task_ppid_nr_ns(tsk, &init_pid_ns);
1419 /* Obsolete, do not use: */
1420 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1422 return task_pgrp_nr_ns(tsk, &init_pid_ns);
1425 #define TASK_REPORT_IDLE (TASK_REPORT + 1)
1426 #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1)
1428 static inline unsigned int task_state_index(struct task_struct *tsk)
1430 unsigned int tsk_state = READ_ONCE(tsk->state);
1431 unsigned int state = (tsk_state | tsk->exit_state) & TASK_REPORT;
1433 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
1435 if (tsk_state == TASK_IDLE)
1436 state = TASK_REPORT_IDLE;
1441 static inline char task_index_to_char(unsigned int state)
1443 static const char state_char[] = "RSDTtXZPI";
1445 BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1);
1447 return state_char[state];
1450 static inline char task_state_to_char(struct task_struct *tsk)
1452 return task_index_to_char(task_state_index(tsk));
1456 * is_global_init - check if a task structure is init. Since init
1457 * is free to have sub-threads we need to check tgid.
1458 * @tsk: Task structure to be checked.
1460 * Check if a task structure is the first user space task the kernel created.
1462 * Return: 1 if the task structure is init. 0 otherwise.
1464 static inline int is_global_init(struct task_struct *tsk)
1466 return task_tgid_nr(tsk) == 1;
1469 extern struct pid *cad_pid;
1474 #define PF_IDLE 0x00000002 /* I am an IDLE thread */
1475 #define PF_EXITING 0x00000004 /* Getting shut down */
1476 #define PF_VCPU 0x00000010 /* I'm a virtual CPU */
1477 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */
1478 #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */
1479 #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */
1480 #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */
1481 #define PF_DUMPCORE 0x00000200 /* Dumped core */
1482 #define PF_SIGNALED 0x00000400 /* Killed by a signal */
1483 #define PF_MEMALLOC 0x00000800 /* Allocating memory */
1484 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */
1485 #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */
1486 #define PF_USED_ASYNC 0x00004000 /* Used async_schedule*(), used by module init */
1487 #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */
1488 #define PF_FROZEN 0x00010000 /* Frozen for system suspend */
1489 #define PF_KSWAPD 0x00020000 /* I am kswapd */
1490 #define PF_MEMALLOC_NOFS 0x00040000 /* All allocation requests will inherit GFP_NOFS */
1491 #define PF_MEMALLOC_NOIO 0x00080000 /* All allocation requests will inherit GFP_NOIO */
1492 #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
1493 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */
1494 #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */
1495 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1496 #define PF_UMH 0x02000000 /* I'm an Usermodehelper process */
1497 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */
1498 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
1499 #define PF_MEMALLOC_NOCMA 0x10000000 /* All allocation request will have _GFP_MOVABLE cleared */
1500 #define PF_IO_WORKER 0x20000000 /* Task is an IO worker */
1501 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */
1502 #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */
1505 * Only the _current_ task can read/write to tsk->flags, but other
1506 * tasks can access tsk->flags in readonly mode for example
1507 * with tsk_used_math (like during threaded core dumping).
1508 * There is however an exception to this rule during ptrace
1509 * or during fork: the ptracer task is allowed to write to the
1510 * child->flags of its traced child (same goes for fork, the parent
1511 * can write to the child->flags), because we're guaranteed the
1512 * child is not running and in turn not changing child->flags
1513 * at the same time the parent does it.
1515 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1516 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1517 #define clear_used_math() clear_stopped_child_used_math(current)
1518 #define set_used_math() set_stopped_child_used_math(current)
1520 #define conditional_stopped_child_used_math(condition, child) \
1521 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1523 #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current)
1525 #define copy_to_stopped_child_used_math(child) \
1526 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1528 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1529 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1530 #define used_math() tsk_used_math(current)
1532 static inline bool is_percpu_thread(void)
1535 return (current->flags & PF_NO_SETAFFINITY) &&
1536 (current->nr_cpus_allowed == 1);
1542 /* Per-process atomic flags. */
1543 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */
1544 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */
1545 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */
1546 #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */
1547 #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/
1548 #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */
1549 #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */
1550 #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */
1552 #define TASK_PFA_TEST(name, func) \
1553 static inline bool task_##func(struct task_struct *p) \
1554 { return test_bit(PFA_##name, &p->atomic_flags); }
1556 #define TASK_PFA_SET(name, func) \
1557 static inline void task_set_##func(struct task_struct *p) \
1558 { set_bit(PFA_##name, &p->atomic_flags); }
1560 #define TASK_PFA_CLEAR(name, func) \
1561 static inline void task_clear_##func(struct task_struct *p) \
1562 { clear_bit(PFA_##name, &p->atomic_flags); }
1564 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1565 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1567 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1568 TASK_PFA_SET(SPREAD_PAGE, spread_page)
1569 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
1571 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
1572 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
1573 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
1575 TASK_PFA_TEST(SPEC_SSB_DISABLE, spec_ssb_disable)
1576 TASK_PFA_SET(SPEC_SSB_DISABLE, spec_ssb_disable)
1577 TASK_PFA_CLEAR(SPEC_SSB_DISABLE, spec_ssb_disable)
1579 TASK_PFA_TEST(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1580 TASK_PFA_SET(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1581 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC, spec_ssb_noexec)
1583 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1584 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE, spec_ssb_force_disable)
1586 TASK_PFA_TEST(SPEC_IB_DISABLE, spec_ib_disable)
1587 TASK_PFA_SET(SPEC_IB_DISABLE, spec_ib_disable)
1588 TASK_PFA_CLEAR(SPEC_IB_DISABLE, spec_ib_disable)
1590 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1591 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE, spec_ib_force_disable)
1594 current_restore_flags(unsigned long orig_flags, unsigned long flags)
1596 current->flags &= ~flags;
1597 current->flags |= orig_flags & flags;
1600 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
1601 extern int task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
1603 extern void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask);
1604 extern int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask);
1606 static inline void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
1609 static inline int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
1611 if (!cpumask_test_cpu(0, new_mask))
1617 extern int yield_to(struct task_struct *p, bool preempt);
1618 extern void set_user_nice(struct task_struct *p, long nice);
1619 extern int task_prio(const struct task_struct *p);
1622 * task_nice - return the nice value of a given task.
1623 * @p: the task in question.
1625 * Return: The nice value [ -20 ... 0 ... 19 ].
1627 static inline int task_nice(const struct task_struct *p)
1629 return PRIO_TO_NICE((p)->static_prio);
1632 extern int can_nice(const struct task_struct *p, const int nice);
1633 extern int task_curr(const struct task_struct *p);
1634 extern int idle_cpu(int cpu);
1635 extern int available_idle_cpu(int cpu);
1636 extern int sched_setscheduler(struct task_struct *, int, const struct sched_param *);
1637 extern int sched_setscheduler_nocheck(struct task_struct *, int, const struct sched_param *);
1638 extern int sched_setattr(struct task_struct *, const struct sched_attr *);
1639 extern int sched_setattr_nocheck(struct task_struct *, const struct sched_attr *);
1640 extern struct task_struct *idle_task(int cpu);
1643 * is_idle_task - is the specified task an idle task?
1644 * @p: the task in question.
1646 * Return: 1 if @p is an idle task. 0 otherwise.
1648 static inline bool is_idle_task(const struct task_struct *p)
1650 return !!(p->flags & PF_IDLE);
1653 extern struct task_struct *curr_task(int cpu);
1654 extern void ia64_set_curr_task(int cpu, struct task_struct *p);
1658 union thread_union {
1659 #ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK
1660 struct task_struct task;
1662 #ifndef CONFIG_THREAD_INFO_IN_TASK
1663 struct thread_info thread_info;
1665 unsigned long stack[THREAD_SIZE/sizeof(long)];
1668 #ifndef CONFIG_THREAD_INFO_IN_TASK
1669 extern struct thread_info init_thread_info;
1672 extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)];
1674 #ifdef CONFIG_THREAD_INFO_IN_TASK
1675 static inline struct thread_info *task_thread_info(struct task_struct *task)
1677 return &task->thread_info;
1679 #elif !defined(__HAVE_THREAD_FUNCTIONS)
1680 # define task_thread_info(task) ((struct thread_info *)(task)->stack)
1684 * find a task by one of its numerical ids
1686 * find_task_by_pid_ns():
1687 * finds a task by its pid in the specified namespace
1688 * find_task_by_vpid():
1689 * finds a task by its virtual pid
1691 * see also find_vpid() etc in include/linux/pid.h
1694 extern struct task_struct *find_task_by_vpid(pid_t nr);
1695 extern struct task_struct *find_task_by_pid_ns(pid_t nr, struct pid_namespace *ns);
1698 * find a task by its virtual pid and get the task struct
1700 extern struct task_struct *find_get_task_by_vpid(pid_t nr);
1702 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1703 extern int wake_up_process(struct task_struct *tsk);
1704 extern void wake_up_new_task(struct task_struct *tsk);
1707 extern void kick_process(struct task_struct *tsk);
1709 static inline void kick_process(struct task_struct *tsk) { }
1712 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
1714 static inline void set_task_comm(struct task_struct *tsk, const char *from)
1716 __set_task_comm(tsk, from, false);
1719 extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk);
1720 #define get_task_comm(buf, tsk) ({ \
1721 BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN); \
1722 __get_task_comm(buf, sizeof(buf), tsk); \
1726 void scheduler_ipi(void);
1727 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
1729 static inline void scheduler_ipi(void) { }
1730 static inline unsigned long wait_task_inactive(struct task_struct *p, long match_state)
1737 * Set thread flags in other task's structures.
1738 * See asm/thread_info.h for TIF_xxxx flags available:
1740 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
1742 set_ti_thread_flag(task_thread_info(tsk), flag);
1745 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1747 clear_ti_thread_flag(task_thread_info(tsk), flag);
1750 static inline void update_tsk_thread_flag(struct task_struct *tsk, int flag,
1753 update_ti_thread_flag(task_thread_info(tsk), flag, value);
1756 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
1758 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
1761 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
1763 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
1766 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
1768 return test_ti_thread_flag(task_thread_info(tsk), flag);
1771 static inline void set_tsk_need_resched(struct task_struct *tsk)
1773 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1776 static inline void clear_tsk_need_resched(struct task_struct *tsk)
1778 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
1781 static inline int test_tsk_need_resched(struct task_struct *tsk)
1783 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
1787 * cond_resched() and cond_resched_lock(): latency reduction via
1788 * explicit rescheduling in places that are safe. The return
1789 * value indicates whether a reschedule was done in fact.
1790 * cond_resched_lock() will drop the spinlock before scheduling,
1792 #ifndef CONFIG_PREEMPTION
1793 extern int _cond_resched(void);
1795 static inline int _cond_resched(void) { return 0; }
1798 #define cond_resched() ({ \
1799 ___might_sleep(__FILE__, __LINE__, 0); \
1803 extern int __cond_resched_lock(spinlock_t *lock);
1805 #define cond_resched_lock(lock) ({ \
1806 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
1807 __cond_resched_lock(lock); \
1810 static inline void cond_resched_rcu(void)
1812 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
1820 * Does a critical section need to be broken due to another
1821 * task waiting?: (technically does not depend on CONFIG_PREEMPTION,
1822 * but a general need for low latency)
1824 static inline int spin_needbreak(spinlock_t *lock)
1826 #ifdef CONFIG_PREEMPTION
1827 return spin_is_contended(lock);
1833 static __always_inline bool need_resched(void)
1835 return unlikely(tif_need_resched());
1839 * Wrappers for p->thread_info->cpu access. No-op on UP.
1843 static inline unsigned int task_cpu(const struct task_struct *p)
1845 #ifdef CONFIG_THREAD_INFO_IN_TASK
1846 return READ_ONCE(p->cpu);
1848 return READ_ONCE(task_thread_info(p)->cpu);
1852 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
1856 static inline unsigned int task_cpu(const struct task_struct *p)
1861 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
1865 #endif /* CONFIG_SMP */
1868 * In order to reduce various lock holder preemption latencies provide an
1869 * interface to see if a vCPU is currently running or not.
1871 * This allows us to terminate optimistic spin loops and block, analogous to
1872 * the native optimistic spin heuristic of testing if the lock owner task is
1875 #ifndef vcpu_is_preempted
1876 static inline bool vcpu_is_preempted(int cpu)
1882 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
1883 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
1885 #ifndef TASK_SIZE_OF
1886 #define TASK_SIZE_OF(tsk) TASK_SIZE
1892 * Map the event mask on the user-space ABI enum rseq_cs_flags
1893 * for direct mask checks.
1895 enum rseq_event_mask_bits {
1896 RSEQ_EVENT_PREEMPT_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT,
1897 RSEQ_EVENT_SIGNAL_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT,
1898 RSEQ_EVENT_MIGRATE_BIT = RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT,
1901 enum rseq_event_mask {
1902 RSEQ_EVENT_PREEMPT = (1U << RSEQ_EVENT_PREEMPT_BIT),
1903 RSEQ_EVENT_SIGNAL = (1U << RSEQ_EVENT_SIGNAL_BIT),
1904 RSEQ_EVENT_MIGRATE = (1U << RSEQ_EVENT_MIGRATE_BIT),
1907 static inline void rseq_set_notify_resume(struct task_struct *t)
1910 set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
1913 void __rseq_handle_notify_resume(struct ksignal *sig, struct pt_regs *regs);
1915 static inline void rseq_handle_notify_resume(struct ksignal *ksig,
1916 struct pt_regs *regs)
1919 __rseq_handle_notify_resume(ksig, regs);
1922 static inline void rseq_signal_deliver(struct ksignal *ksig,
1923 struct pt_regs *regs)
1926 __set_bit(RSEQ_EVENT_SIGNAL_BIT, ¤t->rseq_event_mask);
1928 rseq_handle_notify_resume(ksig, regs);
1931 /* rseq_preempt() requires preemption to be disabled. */
1932 static inline void rseq_preempt(struct task_struct *t)
1934 __set_bit(RSEQ_EVENT_PREEMPT_BIT, &t->rseq_event_mask);
1935 rseq_set_notify_resume(t);
1938 /* rseq_migrate() requires preemption to be disabled. */
1939 static inline void rseq_migrate(struct task_struct *t)
1941 __set_bit(RSEQ_EVENT_MIGRATE_BIT, &t->rseq_event_mask);
1942 rseq_set_notify_resume(t);
1946 * If parent process has a registered restartable sequences area, the
1947 * child inherits. Unregister rseq for a clone with CLONE_VM set.
1949 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
1951 if (clone_flags & CLONE_VM) {
1954 t->rseq_event_mask = 0;
1956 t->rseq = current->rseq;
1957 t->rseq_sig = current->rseq_sig;
1958 t->rseq_event_mask = current->rseq_event_mask;
1962 static inline void rseq_execve(struct task_struct *t)
1966 t->rseq_event_mask = 0;
1971 static inline void rseq_set_notify_resume(struct task_struct *t)
1974 static inline void rseq_handle_notify_resume(struct ksignal *ksig,
1975 struct pt_regs *regs)
1978 static inline void rseq_signal_deliver(struct ksignal *ksig,
1979 struct pt_regs *regs)
1982 static inline void rseq_preempt(struct task_struct *t)
1985 static inline void rseq_migrate(struct task_struct *t)
1988 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
1991 static inline void rseq_execve(struct task_struct *t)
1997 void __exit_umh(struct task_struct *tsk);
1999 static inline void exit_umh(struct task_struct *tsk)
2001 if (unlikely(tsk->flags & PF_UMH))
2005 #ifdef CONFIG_DEBUG_RSEQ
2007 void rseq_syscall(struct pt_regs *regs);
2011 static inline void rseq_syscall(struct pt_regs *regs)
2017 const struct sched_avg *sched_trace_cfs_rq_avg(struct cfs_rq *cfs_rq);
2018 char *sched_trace_cfs_rq_path(struct cfs_rq *cfs_rq, char *str, int len);
2019 int sched_trace_cfs_rq_cpu(struct cfs_rq *cfs_rq);
2021 const struct sched_avg *sched_trace_rq_avg_rt(struct rq *rq);
2022 const struct sched_avg *sched_trace_rq_avg_dl(struct rq *rq);
2023 const struct sched_avg *sched_trace_rq_avg_irq(struct rq *rq);
2025 int sched_trace_rq_cpu(struct rq *rq);
2027 const struct cpumask *sched_trace_rd_span(struct root_domain *rd);