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
;
657 unsigned int wake_entry_type
;
659 #ifdef CONFIG_THREAD_INFO_IN_TASK
663 unsigned int wakee_flips
;
664 unsigned long wakee_flip_decay_ts
;
665 struct task_struct
*last_wakee
;
668 * recent_used_cpu is initially set as the last CPU used by a task
669 * that wakes affine another task. Waker/wakee relationships can
670 * push tasks around a CPU where each wakeup moves to the next one.
671 * Tracking a recently used CPU allows a quick search for a recently
672 * used CPU that may be idle.
682 unsigned int rt_priority
;
684 const struct sched_class
*sched_class
;
685 struct sched_entity se
;
686 struct sched_rt_entity rt
;
687 #ifdef CONFIG_CGROUP_SCHED
688 struct task_group
*sched_task_group
;
690 struct sched_dl_entity dl
;
692 #ifdef CONFIG_UCLAMP_TASK
693 /* Clamp values requested for a scheduling entity */
694 struct uclamp_se uclamp_req
[UCLAMP_CNT
];
695 /* Effective clamp values used for a scheduling entity */
696 struct uclamp_se uclamp
[UCLAMP_CNT
];
699 #ifdef CONFIG_PREEMPT_NOTIFIERS
700 /* List of struct preempt_notifier: */
701 struct hlist_head preempt_notifiers
;
704 #ifdef CONFIG_BLK_DEV_IO_TRACE
705 unsigned int btrace_seq
;
710 const cpumask_t
*cpus_ptr
;
713 #ifdef CONFIG_PREEMPT_RCU
714 int rcu_read_lock_nesting
;
715 union rcu_special rcu_read_unlock_special
;
716 struct list_head rcu_node_entry
;
717 struct rcu_node
*rcu_blocked_node
;
718 #endif /* #ifdef CONFIG_PREEMPT_RCU */
720 #ifdef CONFIG_TASKS_RCU
721 unsigned long rcu_tasks_nvcsw
;
722 u8 rcu_tasks_holdout
;
724 int rcu_tasks_idle_cpu
;
725 struct list_head rcu_tasks_holdout_list
;
726 #endif /* #ifdef CONFIG_TASKS_RCU */
728 #ifdef CONFIG_TASKS_TRACE_RCU
729 int trc_reader_nesting
;
731 union rcu_special trc_reader_special
;
732 bool trc_reader_checked
;
733 struct list_head trc_holdout_list
;
734 #endif /* #ifdef CONFIG_TASKS_TRACE_RCU */
736 struct sched_info sched_info
;
738 struct list_head tasks
;
740 struct plist_node pushable_tasks
;
741 struct rb_node pushable_dl_tasks
;
744 struct mm_struct
*mm
;
745 struct mm_struct
*active_mm
;
747 /* Per-thread vma caching: */
748 struct vmacache vmacache
;
750 #ifdef SPLIT_RSS_COUNTING
751 struct task_rss_stat rss_stat
;
756 /* The signal sent when the parent dies: */
758 /* JOBCTL_*, siglock protected: */
759 unsigned long jobctl
;
761 /* Used for emulating ABI behavior of previous Linux versions: */
762 unsigned int personality
;
764 /* Scheduler bits, serialized by scheduler locks: */
765 unsigned sched_reset_on_fork
:1;
766 unsigned sched_contributes_to_load
:1;
767 unsigned sched_migrated
:1;
768 unsigned sched_remote_wakeup
:1;
770 unsigned sched_psi_wake_requeue
:1;
773 /* Force alignment to the next boundary: */
776 /* Unserialized, strictly 'current' */
778 /* Bit to tell LSMs we're in execve(): */
779 unsigned in_execve
:1;
780 unsigned in_iowait
:1;
781 #ifndef TIF_RESTORE_SIGMASK
782 unsigned restore_sigmask
:1;
785 unsigned in_user_fault
:1;
787 #ifdef CONFIG_COMPAT_BRK
788 unsigned brk_randomized
:1;
790 #ifdef CONFIG_CGROUPS
791 /* disallow userland-initiated cgroup migration */
792 unsigned no_cgroup_migration
:1;
793 /* task is frozen/stopped (used by the cgroup freezer) */
796 #ifdef CONFIG_BLK_CGROUP
797 unsigned use_memdelay
:1;
800 /* Stalled due to lack of memory */
801 unsigned in_memstall
:1;
804 unsigned long atomic_flags
; /* Flags requiring atomic access. */
806 struct restart_block restart_block
;
811 #ifdef CONFIG_STACKPROTECTOR
812 /* Canary value for the -fstack-protector GCC feature: */
813 unsigned long stack_canary
;
816 * Pointers to the (original) parent process, youngest child, younger sibling,
817 * older sibling, respectively. (p->father can be replaced with
818 * p->real_parent->pid)
821 /* Real parent process: */
822 struct task_struct __rcu
*real_parent
;
824 /* Recipient of SIGCHLD, wait4() reports: */
825 struct task_struct __rcu
*parent
;
828 * Children/sibling form the list of natural children:
830 struct list_head children
;
831 struct list_head sibling
;
832 struct task_struct
*group_leader
;
835 * 'ptraced' is the list of tasks this task is using ptrace() on.
837 * This includes both natural children and PTRACE_ATTACH targets.
838 * 'ptrace_entry' is this task's link on the p->parent->ptraced list.
840 struct list_head ptraced
;
841 struct list_head ptrace_entry
;
843 /* PID/PID hash table linkage. */
844 struct pid
*thread_pid
;
845 struct hlist_node pid_links
[PIDTYPE_MAX
];
846 struct list_head thread_group
;
847 struct list_head thread_node
;
849 struct completion
*vfork_done
;
851 /* CLONE_CHILD_SETTID: */
852 int __user
*set_child_tid
;
854 /* CLONE_CHILD_CLEARTID: */
855 int __user
*clear_child_tid
;
859 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
864 struct prev_cputime prev_cputime
;
865 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
869 #ifdef CONFIG_NO_HZ_FULL
870 atomic_t tick_dep_mask
;
872 /* Context switch counts: */
874 unsigned long nivcsw
;
876 /* Monotonic time in nsecs: */
879 /* Boot based time in nsecs: */
882 /* MM fault and swap info: this can arguably be seen as either mm-specific or thread-specific: */
883 unsigned long min_flt
;
884 unsigned long maj_flt
;
886 /* Empty if CONFIG_POSIX_CPUTIMERS=n */
887 struct posix_cputimers posix_cputimers
;
889 /* Process credentials: */
891 /* Tracer's credentials at attach: */
892 const struct cred __rcu
*ptracer_cred
;
894 /* Objective and real subjective task credentials (COW): */
895 const struct cred __rcu
*real_cred
;
897 /* Effective (overridable) subjective task credentials (COW): */
898 const struct cred __rcu
*cred
;
901 /* Cached requested key. */
902 struct key
*cached_requested_key
;
906 * executable name, excluding path.
908 * - normally initialized setup_new_exec()
909 * - access it with [gs]et_task_comm()
910 * - lock it with task_lock()
912 char comm
[TASK_COMM_LEN
];
914 struct nameidata
*nameidata
;
916 #ifdef CONFIG_SYSVIPC
917 struct sysv_sem sysvsem
;
918 struct sysv_shm sysvshm
;
920 #ifdef CONFIG_DETECT_HUNG_TASK
921 unsigned long last_switch_count
;
922 unsigned long last_switch_time
;
924 /* Filesystem information: */
925 struct fs_struct
*fs
;
927 /* Open file information: */
928 struct files_struct
*files
;
931 struct nsproxy
*nsproxy
;
933 /* Signal handlers: */
934 struct signal_struct
*signal
;
935 struct sighand_struct __rcu
*sighand
;
937 sigset_t real_blocked
;
938 /* Restored if set_restore_sigmask() was used: */
939 sigset_t saved_sigmask
;
940 struct sigpending pending
;
941 unsigned long sas_ss_sp
;
943 unsigned int sas_ss_flags
;
945 struct callback_head
*task_works
;
948 #ifdef CONFIG_AUDITSYSCALL
949 struct audit_context
*audit_context
;
952 unsigned int sessionid
;
954 struct seccomp seccomp
;
956 /* Thread group tracking: */
960 /* Protection against (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed, mempolicy: */
961 spinlock_t alloc_lock
;
963 /* Protection of the PI data structures: */
964 raw_spinlock_t pi_lock
;
966 struct wake_q_node wake_q
;
968 #ifdef CONFIG_RT_MUTEXES
969 /* PI waiters blocked on a rt_mutex held by this task: */
970 struct rb_root_cached pi_waiters
;
971 /* Updated under owner's pi_lock and rq lock */
972 struct task_struct
*pi_top_task
;
973 /* Deadlock detection and priority inheritance handling: */
974 struct rt_mutex_waiter
*pi_blocked_on
;
977 #ifdef CONFIG_DEBUG_MUTEXES
978 /* Mutex deadlock detection: */
979 struct mutex_waiter
*blocked_on
;
982 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
986 #ifdef CONFIG_TRACE_IRQFLAGS
987 unsigned int irq_events
;
988 unsigned int hardirq_threaded
;
989 unsigned long hardirq_enable_ip
;
990 unsigned long hardirq_disable_ip
;
991 unsigned int hardirq_enable_event
;
992 unsigned int hardirq_disable_event
;
993 int hardirqs_enabled
;
995 u64 hardirq_chain_key
;
996 unsigned long softirq_disable_ip
;
997 unsigned long softirq_enable_ip
;
998 unsigned int softirq_disable_event
;
999 unsigned int softirq_enable_event
;
1000 int softirqs_enabled
;
1001 int softirq_context
;
1005 #ifdef CONFIG_LOCKDEP
1006 # define MAX_LOCK_DEPTH 48UL
1009 unsigned int lockdep_recursion
;
1010 struct held_lock held_locks
[MAX_LOCK_DEPTH
];
1014 unsigned int in_ubsan
;
1017 /* Journalling filesystem info: */
1020 /* Stacked block device info: */
1021 struct bio_list
*bio_list
;
1024 /* Stack plugging: */
1025 struct blk_plug
*plug
;
1029 struct reclaim_state
*reclaim_state
;
1031 struct backing_dev_info
*backing_dev_info
;
1033 struct io_context
*io_context
;
1035 #ifdef CONFIG_COMPACTION
1036 struct capture_control
*capture_control
;
1039 unsigned long ptrace_message
;
1040 kernel_siginfo_t
*last_siginfo
;
1042 struct task_io_accounting ioac
;
1044 /* Pressure stall state */
1045 unsigned int psi_flags
;
1047 #ifdef CONFIG_TASK_XACCT
1048 /* Accumulated RSS usage: */
1050 /* Accumulated virtual memory usage: */
1052 /* stime + utime since last update: */
1055 #ifdef CONFIG_CPUSETS
1056 /* Protected by ->alloc_lock: */
1057 nodemask_t mems_allowed
;
1058 /* Seqence number to catch updates: */
1059 seqcount_t mems_allowed_seq
;
1060 int cpuset_mem_spread_rotor
;
1061 int cpuset_slab_spread_rotor
;
1063 #ifdef CONFIG_CGROUPS
1064 /* Control Group info protected by css_set_lock: */
1065 struct css_set __rcu
*cgroups
;
1066 /* cg_list protected by css_set_lock and tsk->alloc_lock: */
1067 struct list_head cg_list
;
1069 #ifdef CONFIG_X86_CPU_RESCTRL
1074 struct robust_list_head __user
*robust_list
;
1075 #ifdef CONFIG_COMPAT
1076 struct compat_robust_list_head __user
*compat_robust_list
;
1078 struct list_head pi_state_list
;
1079 struct futex_pi_state
*pi_state_cache
;
1080 struct mutex futex_exit_mutex
;
1081 unsigned int futex_state
;
1083 #ifdef CONFIG_PERF_EVENTS
1084 struct perf_event_context
*perf_event_ctxp
[perf_nr_task_contexts
];
1085 struct mutex perf_event_mutex
;
1086 struct list_head perf_event_list
;
1088 #ifdef CONFIG_DEBUG_PREEMPT
1089 unsigned long preempt_disable_ip
;
1092 /* Protected by alloc_lock: */
1093 struct mempolicy
*mempolicy
;
1095 short pref_node_fork
;
1097 #ifdef CONFIG_NUMA_BALANCING
1099 unsigned int numa_scan_period
;
1100 unsigned int numa_scan_period_max
;
1101 int numa_preferred_nid
;
1102 unsigned long numa_migrate_retry
;
1103 /* Migration stamp: */
1105 u64 last_task_numa_placement
;
1106 u64 last_sum_exec_runtime
;
1107 struct callback_head numa_work
;
1110 * This pointer is only modified for current in syscall and
1111 * pagefault context (and for tasks being destroyed), so it can be read
1112 * from any of the following contexts:
1113 * - RCU read-side critical section
1114 * - current->numa_group from everywhere
1115 * - task's runqueue locked, task not running
1117 struct numa_group __rcu
*numa_group
;
1120 * numa_faults is an array split into four regions:
1121 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1122 * in this precise order.
1124 * faults_memory: Exponential decaying average of faults on a per-node
1125 * basis. Scheduling placement decisions are made based on these
1126 * counts. The values remain static for the duration of a PTE scan.
1127 * faults_cpu: Track the nodes the process was running on when a NUMA
1128 * hinting fault was incurred.
1129 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1130 * during the current scan window. When the scan completes, the counts
1131 * in faults_memory and faults_cpu decay and these values are copied.
1133 unsigned long *numa_faults
;
1134 unsigned long total_numa_faults
;
1137 * numa_faults_locality tracks if faults recorded during the last
1138 * scan window were remote/local or failed to migrate. The task scan
1139 * period is adapted based on the locality of the faults with different
1140 * weights depending on whether they were shared or private faults
1142 unsigned long numa_faults_locality
[3];
1144 unsigned long numa_pages_migrated
;
1145 #endif /* CONFIG_NUMA_BALANCING */
1148 struct rseq __user
*rseq
;
1151 * RmW on rseq_event_mask must be performed atomically
1152 * with respect to preemption.
1154 unsigned long rseq_event_mask
;
1157 struct tlbflush_unmap_batch tlb_ubc
;
1160 refcount_t rcu_users
;
1161 struct rcu_head rcu
;
1164 /* Cache last used pipe for splice(): */
1165 struct pipe_inode_info
*splice_pipe
;
1167 struct page_frag task_frag
;
1169 #ifdef CONFIG_TASK_DELAY_ACCT
1170 struct task_delay_info
*delays
;
1173 #ifdef CONFIG_FAULT_INJECTION
1175 unsigned int fail_nth
;
1178 * When (nr_dirtied >= nr_dirtied_pause), it's time to call
1179 * balance_dirty_pages() for a dirty throttling pause:
1182 int nr_dirtied_pause
;
1183 /* Start of a write-and-pause period: */
1184 unsigned long dirty_paused_when
;
1186 #ifdef CONFIG_LATENCYTOP
1187 int latency_record_count
;
1188 struct latency_record latency_record
[LT_SAVECOUNT
];
1191 * Time slack values; these are used to round up poll() and
1192 * select() etc timeout values. These are in nanoseconds.
1195 u64 default_timer_slack_ns
;
1198 unsigned int kasan_depth
;
1201 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1202 /* Index of current stored address in ret_stack: */
1206 /* Stack of return addresses for return function tracing: */
1207 struct ftrace_ret_stack
*ret_stack
;
1209 /* Timestamp for last schedule: */
1210 unsigned long long ftrace_timestamp
;
1213 * Number of functions that haven't been traced
1214 * because of depth overrun:
1216 atomic_t trace_overrun
;
1218 /* Pause tracing: */
1219 atomic_t tracing_graph_pause
;
1222 #ifdef CONFIG_TRACING
1223 /* State flags for use by tracers: */
1224 unsigned long trace
;
1226 /* Bitmask and counter of trace recursion: */
1227 unsigned long trace_recursion
;
1228 #endif /* CONFIG_TRACING */
1231 /* See kernel/kcov.c for more details. */
1233 /* Coverage collection mode enabled for this task (0 if disabled): */
1234 unsigned int kcov_mode
;
1236 /* Size of the kcov_area: */
1237 unsigned int kcov_size
;
1239 /* Buffer for coverage collection: */
1242 /* KCOV descriptor wired with this task or NULL: */
1245 /* KCOV common handle for remote coverage collection: */
1248 /* KCOV sequence number: */
1251 /* Collect coverage from softirq context: */
1252 unsigned int kcov_softirq
;
1256 struct mem_cgroup
*memcg_in_oom
;
1257 gfp_t memcg_oom_gfp_mask
;
1258 int memcg_oom_order
;
1260 /* Number of pages to reclaim on returning to userland: */
1261 unsigned int memcg_nr_pages_over_high
;
1263 /* Used by memcontrol for targeted memcg charge: */
1264 struct mem_cgroup
*active_memcg
;
1267 #ifdef CONFIG_BLK_CGROUP
1268 struct request_queue
*throttle_queue
;
1271 #ifdef CONFIG_UPROBES
1272 struct uprobe_task
*utask
;
1274 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1275 unsigned int sequential_io
;
1276 unsigned int sequential_io_avg
;
1278 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1279 unsigned long task_state_change
;
1281 int pagefault_disabled
;
1283 struct task_struct
*oom_reaper_list
;
1285 #ifdef CONFIG_VMAP_STACK
1286 struct vm_struct
*stack_vm_area
;
1288 #ifdef CONFIG_THREAD_INFO_IN_TASK
1289 /* A live task holds one reference: */
1290 refcount_t stack_refcount
;
1292 #ifdef CONFIG_LIVEPATCH
1295 #ifdef CONFIG_SECURITY
1296 /* Used by LSM modules for access restriction: */
1300 #ifdef CONFIG_GCC_PLUGIN_STACKLEAK
1301 unsigned long lowest_stack
;
1302 unsigned long prev_lowest_stack
;
1305 #ifdef CONFIG_X86_MCE
1308 struct callback_head mce_kill_me
;
1312 * New fields for task_struct should be added above here, so that
1313 * they are included in the randomized portion of task_struct.
1315 randomized_struct_fields_end
1317 /* CPU-specific state of this task: */
1318 struct thread_struct thread
;
1321 * WARNING: on x86, 'thread_struct' contains a variable-sized
1322 * structure. It *MUST* be at the end of 'task_struct'.
1324 * Do not put anything below here!
1328 static inline struct pid
*task_pid(struct task_struct
*task
)
1330 return task
->thread_pid
;
1334 * the helpers to get the task's different pids as they are seen
1335 * from various namespaces
1337 * task_xid_nr() : global id, i.e. the id seen from the init namespace;
1338 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of
1340 * task_xid_nr_ns() : id seen from the ns specified;
1342 * see also pid_nr() etc in include/linux/pid.h
1344 pid_t
__task_pid_nr_ns(struct task_struct
*task
, enum pid_type type
, struct pid_namespace
*ns
);
1346 static inline pid_t
task_pid_nr(struct task_struct
*tsk
)
1351 static inline pid_t
task_pid_nr_ns(struct task_struct
*tsk
, struct pid_namespace
*ns
)
1353 return __task_pid_nr_ns(tsk
, PIDTYPE_PID
, ns
);
1356 static inline pid_t
task_pid_vnr(struct task_struct
*tsk
)
1358 return __task_pid_nr_ns(tsk
, PIDTYPE_PID
, NULL
);
1362 static inline pid_t
task_tgid_nr(struct task_struct
*tsk
)
1368 * pid_alive - check that a task structure is not stale
1369 * @p: Task structure to be checked.
1371 * Test if a process is not yet dead (at most zombie state)
1372 * If pid_alive fails, then pointers within the task structure
1373 * can be stale and must not be dereferenced.
1375 * Return: 1 if the process is alive. 0 otherwise.
1377 static inline int pid_alive(const struct task_struct
*p
)
1379 return p
->thread_pid
!= NULL
;
1382 static inline pid_t
task_pgrp_nr_ns(struct task_struct
*tsk
, struct pid_namespace
*ns
)
1384 return __task_pid_nr_ns(tsk
, PIDTYPE_PGID
, ns
);
1387 static inline pid_t
task_pgrp_vnr(struct task_struct
*tsk
)
1389 return __task_pid_nr_ns(tsk
, PIDTYPE_PGID
, NULL
);
1393 static inline pid_t
task_session_nr_ns(struct task_struct
*tsk
, struct pid_namespace
*ns
)
1395 return __task_pid_nr_ns(tsk
, PIDTYPE_SID
, ns
);
1398 static inline pid_t
task_session_vnr(struct task_struct
*tsk
)
1400 return __task_pid_nr_ns(tsk
, PIDTYPE_SID
, NULL
);
1403 static inline pid_t
task_tgid_nr_ns(struct task_struct
*tsk
, struct pid_namespace
*ns
)
1405 return __task_pid_nr_ns(tsk
, PIDTYPE_TGID
, ns
);
1408 static inline pid_t
task_tgid_vnr(struct task_struct
*tsk
)
1410 return __task_pid_nr_ns(tsk
, PIDTYPE_TGID
, NULL
);
1413 static inline pid_t
task_ppid_nr_ns(const struct task_struct
*tsk
, struct pid_namespace
*ns
)
1419 pid
= task_tgid_nr_ns(rcu_dereference(tsk
->real_parent
), ns
);
1425 static inline pid_t
task_ppid_nr(const struct task_struct
*tsk
)
1427 return task_ppid_nr_ns(tsk
, &init_pid_ns
);
1430 /* Obsolete, do not use: */
1431 static inline pid_t
task_pgrp_nr(struct task_struct
*tsk
)
1433 return task_pgrp_nr_ns(tsk
, &init_pid_ns
);
1436 #define TASK_REPORT_IDLE (TASK_REPORT + 1)
1437 #define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1)
1439 static inline unsigned int task_state_index(struct task_struct
*tsk
)
1441 unsigned int tsk_state
= READ_ONCE(tsk
->state
);
1442 unsigned int state
= (tsk_state
| tsk
->exit_state
) & TASK_REPORT
;
1444 BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX
);
1446 if (tsk_state
== TASK_IDLE
)
1447 state
= TASK_REPORT_IDLE
;
1452 static inline char task_index_to_char(unsigned int state
)
1454 static const char state_char
[] = "RSDTtXZPI";
1456 BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX
) != sizeof(state_char
) - 1);
1458 return state_char
[state
];
1461 static inline char task_state_to_char(struct task_struct
*tsk
)
1463 return task_index_to_char(task_state_index(tsk
));
1467 * is_global_init - check if a task structure is init. Since init
1468 * is free to have sub-threads we need to check tgid.
1469 * @tsk: Task structure to be checked.
1471 * Check if a task structure is the first user space task the kernel created.
1473 * Return: 1 if the task structure is init. 0 otherwise.
1475 static inline int is_global_init(struct task_struct
*tsk
)
1477 return task_tgid_nr(tsk
) == 1;
1480 extern struct pid
*cad_pid
;
1485 #define PF_IDLE 0x00000002 /* I am an IDLE thread */
1486 #define PF_EXITING 0x00000004 /* Getting shut down */
1487 #define PF_VCPU 0x00000010 /* I'm a virtual CPU */
1488 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */
1489 #define PF_FORKNOEXEC 0x00000040 /* Forked but didn't exec */
1490 #define PF_MCE_PROCESS 0x00000080 /* Process policy on mce errors */
1491 #define PF_SUPERPRIV 0x00000100 /* Used super-user privileges */
1492 #define PF_DUMPCORE 0x00000200 /* Dumped core */
1493 #define PF_SIGNALED 0x00000400 /* Killed by a signal */
1494 #define PF_MEMALLOC 0x00000800 /* Allocating memory */
1495 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user() noticed that RLIMIT_NPROC was exceeded */
1496 #define PF_USED_MATH 0x00002000 /* If unset the fpu must be initialized before use */
1497 #define PF_USED_ASYNC 0x00004000 /* Used async_schedule*(), used by module init */
1498 #define PF_NOFREEZE 0x00008000 /* This thread should not be frozen */
1499 #define PF_FROZEN 0x00010000 /* Frozen for system suspend */
1500 #define PF_KSWAPD 0x00020000 /* I am kswapd */
1501 #define PF_MEMALLOC_NOFS 0x00040000 /* All allocation requests will inherit GFP_NOFS */
1502 #define PF_MEMALLOC_NOIO 0x00080000 /* All allocation requests will inherit GFP_NOIO */
1503 #define PF_LOCAL_THROTTLE 0x00100000 /* Throttle writes only against the bdi I write to,
1504 * I am cleaning dirty pages from some other bdi. */
1505 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */
1506 #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */
1507 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1508 #define PF_UMH 0x02000000 /* I'm an Usermodehelper process */
1509 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */
1510 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
1511 #define PF_MEMALLOC_NOCMA 0x10000000 /* All allocation request will have _GFP_MOVABLE cleared */
1512 #define PF_IO_WORKER 0x20000000 /* Task is an IO worker */
1513 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */
1514 #define PF_SUSPEND_TASK 0x80000000 /* This thread called freeze_processes() and should not be frozen */
1517 * Only the _current_ task can read/write to tsk->flags, but other
1518 * tasks can access tsk->flags in readonly mode for example
1519 * with tsk_used_math (like during threaded core dumping).
1520 * There is however an exception to this rule during ptrace
1521 * or during fork: the ptracer task is allowed to write to the
1522 * child->flags of its traced child (same goes for fork, the parent
1523 * can write to the child->flags), because we're guaranteed the
1524 * child is not running and in turn not changing child->flags
1525 * at the same time the parent does it.
1527 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1528 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1529 #define clear_used_math() clear_stopped_child_used_math(current)
1530 #define set_used_math() set_stopped_child_used_math(current)
1532 #define conditional_stopped_child_used_math(condition, child) \
1533 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1535 #define conditional_used_math(condition) conditional_stopped_child_used_math(condition, current)
1537 #define copy_to_stopped_child_used_math(child) \
1538 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1540 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1541 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1542 #define used_math() tsk_used_math(current)
1544 static inline bool is_percpu_thread(void)
1547 return (current
->flags
& PF_NO_SETAFFINITY
) &&
1548 (current
->nr_cpus_allowed
== 1);
1554 /* Per-process atomic flags. */
1555 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */
1556 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */
1557 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */
1558 #define PFA_SPEC_SSB_DISABLE 3 /* Speculative Store Bypass disabled */
1559 #define PFA_SPEC_SSB_FORCE_DISABLE 4 /* Speculative Store Bypass force disabled*/
1560 #define PFA_SPEC_IB_DISABLE 5 /* Indirect branch speculation restricted */
1561 #define PFA_SPEC_IB_FORCE_DISABLE 6 /* Indirect branch speculation permanently restricted */
1562 #define PFA_SPEC_SSB_NOEXEC 7 /* Speculative Store Bypass clear on execve() */
1564 #define TASK_PFA_TEST(name, func) \
1565 static inline bool task_##func(struct task_struct *p) \
1566 { return test_bit(PFA_##name, &p->atomic_flags); }
1568 #define TASK_PFA_SET(name, func) \
1569 static inline void task_set_##func(struct task_struct *p) \
1570 { set_bit(PFA_##name, &p->atomic_flags); }
1572 #define TASK_PFA_CLEAR(name, func) \
1573 static inline void task_clear_##func(struct task_struct *p) \
1574 { clear_bit(PFA_##name, &p->atomic_flags); }
1576 TASK_PFA_TEST(NO_NEW_PRIVS
, no_new_privs
)
1577 TASK_PFA_SET(NO_NEW_PRIVS
, no_new_privs
)
1579 TASK_PFA_TEST(SPREAD_PAGE
, spread_page
)
1580 TASK_PFA_SET(SPREAD_PAGE
, spread_page
)
1581 TASK_PFA_CLEAR(SPREAD_PAGE
, spread_page
)
1583 TASK_PFA_TEST(SPREAD_SLAB
, spread_slab
)
1584 TASK_PFA_SET(SPREAD_SLAB
, spread_slab
)
1585 TASK_PFA_CLEAR(SPREAD_SLAB
, spread_slab
)
1587 TASK_PFA_TEST(SPEC_SSB_DISABLE
, spec_ssb_disable
)
1588 TASK_PFA_SET(SPEC_SSB_DISABLE
, spec_ssb_disable
)
1589 TASK_PFA_CLEAR(SPEC_SSB_DISABLE
, spec_ssb_disable
)
1591 TASK_PFA_TEST(SPEC_SSB_NOEXEC
, spec_ssb_noexec
)
1592 TASK_PFA_SET(SPEC_SSB_NOEXEC
, spec_ssb_noexec
)
1593 TASK_PFA_CLEAR(SPEC_SSB_NOEXEC
, spec_ssb_noexec
)
1595 TASK_PFA_TEST(SPEC_SSB_FORCE_DISABLE
, spec_ssb_force_disable
)
1596 TASK_PFA_SET(SPEC_SSB_FORCE_DISABLE
, spec_ssb_force_disable
)
1598 TASK_PFA_TEST(SPEC_IB_DISABLE
, spec_ib_disable
)
1599 TASK_PFA_SET(SPEC_IB_DISABLE
, spec_ib_disable
)
1600 TASK_PFA_CLEAR(SPEC_IB_DISABLE
, spec_ib_disable
)
1602 TASK_PFA_TEST(SPEC_IB_FORCE_DISABLE
, spec_ib_force_disable
)
1603 TASK_PFA_SET(SPEC_IB_FORCE_DISABLE
, spec_ib_force_disable
)
1606 current_restore_flags(unsigned long orig_flags
, unsigned long flags
)
1608 current
->flags
&= ~flags
;
1609 current
->flags
|= orig_flags
& flags
;
1612 extern int cpuset_cpumask_can_shrink(const struct cpumask
*cur
, const struct cpumask
*trial
);
1613 extern int task_can_attach(struct task_struct
*p
, const struct cpumask
*cs_cpus_allowed
);
1615 extern void do_set_cpus_allowed(struct task_struct
*p
, const struct cpumask
*new_mask
);
1616 extern int set_cpus_allowed_ptr(struct task_struct
*p
, const struct cpumask
*new_mask
);
1618 static inline void do_set_cpus_allowed(struct task_struct
*p
, const struct cpumask
*new_mask
)
1621 static inline int set_cpus_allowed_ptr(struct task_struct
*p
, const struct cpumask
*new_mask
)
1623 if (!cpumask_test_cpu(0, new_mask
))
1629 extern int yield_to(struct task_struct
*p
, bool preempt
);
1630 extern void set_user_nice(struct task_struct
*p
, long nice
);
1631 extern int task_prio(const struct task_struct
*p
);
1634 * task_nice - return the nice value of a given task.
1635 * @p: the task in question.
1637 * Return: The nice value [ -20 ... 0 ... 19 ].
1639 static inline int task_nice(const struct task_struct
*p
)
1641 return PRIO_TO_NICE((p
)->static_prio
);
1644 extern int can_nice(const struct task_struct
*p
, const int nice
);
1645 extern int task_curr(const struct task_struct
*p
);
1646 extern int idle_cpu(int cpu
);
1647 extern int available_idle_cpu(int cpu
);
1648 extern int sched_setscheduler(struct task_struct
*, int, const struct sched_param
*);
1649 extern int sched_setscheduler_nocheck(struct task_struct
*, int, const struct sched_param
*);
1650 extern int sched_setattr(struct task_struct
*, const struct sched_attr
*);
1651 extern int sched_setattr_nocheck(struct task_struct
*, const struct sched_attr
*);
1652 extern struct task_struct
*idle_task(int cpu
);
1655 * is_idle_task - is the specified task an idle task?
1656 * @p: the task in question.
1658 * Return: 1 if @p is an idle task. 0 otherwise.
1660 static inline bool is_idle_task(const struct task_struct
*p
)
1662 return !!(p
->flags
& PF_IDLE
);
1665 extern struct task_struct
*curr_task(int cpu
);
1666 extern void ia64_set_curr_task(int cpu
, struct task_struct
*p
);
1670 union thread_union
{
1671 #ifndef CONFIG_ARCH_TASK_STRUCT_ON_STACK
1672 struct task_struct task
;
1674 #ifndef CONFIG_THREAD_INFO_IN_TASK
1675 struct thread_info thread_info
;
1677 unsigned long stack
[THREAD_SIZE
/sizeof(long)];
1680 #ifndef CONFIG_THREAD_INFO_IN_TASK
1681 extern struct thread_info init_thread_info
;
1684 extern unsigned long init_stack
[THREAD_SIZE
/ sizeof(unsigned long)];
1686 #ifdef CONFIG_THREAD_INFO_IN_TASK
1687 static inline struct thread_info
*task_thread_info(struct task_struct
*task
)
1689 return &task
->thread_info
;
1691 #elif !defined(__HAVE_THREAD_FUNCTIONS)
1692 # define task_thread_info(task) ((struct thread_info *)(task)->stack)
1696 * find a task by one of its numerical ids
1698 * find_task_by_pid_ns():
1699 * finds a task by its pid in the specified namespace
1700 * find_task_by_vpid():
1701 * finds a task by its virtual pid
1703 * see also find_vpid() etc in include/linux/pid.h
1706 extern struct task_struct
*find_task_by_vpid(pid_t nr
);
1707 extern struct task_struct
*find_task_by_pid_ns(pid_t nr
, struct pid_namespace
*ns
);
1710 * find a task by its virtual pid and get the task struct
1712 extern struct task_struct
*find_get_task_by_vpid(pid_t nr
);
1714 extern int wake_up_state(struct task_struct
*tsk
, unsigned int state
);
1715 extern int wake_up_process(struct task_struct
*tsk
);
1716 extern void wake_up_new_task(struct task_struct
*tsk
);
1719 extern void kick_process(struct task_struct
*tsk
);
1721 static inline void kick_process(struct task_struct
*tsk
) { }
1724 extern void __set_task_comm(struct task_struct
*tsk
, const char *from
, bool exec
);
1726 static inline void set_task_comm(struct task_struct
*tsk
, const char *from
)
1728 __set_task_comm(tsk
, from
, false);
1731 extern char *__get_task_comm(char *to
, size_t len
, struct task_struct
*tsk
);
1732 #define get_task_comm(buf, tsk) ({ \
1733 BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN); \
1734 __get_task_comm(buf, sizeof(buf), tsk); \
1738 static __always_inline
void scheduler_ipi(void)
1741 * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
1742 * TIF_NEED_RESCHED remotely (for the first time) will also send
1745 preempt_fold_need_resched();
1747 extern unsigned long wait_task_inactive(struct task_struct
*, long match_state
);
1749 static inline void scheduler_ipi(void) { }
1750 static inline unsigned long wait_task_inactive(struct task_struct
*p
, long match_state
)
1757 * Set thread flags in other task's structures.
1758 * See asm/thread_info.h for TIF_xxxx flags available:
1760 static inline void set_tsk_thread_flag(struct task_struct
*tsk
, int flag
)
1762 set_ti_thread_flag(task_thread_info(tsk
), flag
);
1765 static inline void clear_tsk_thread_flag(struct task_struct
*tsk
, int flag
)
1767 clear_ti_thread_flag(task_thread_info(tsk
), flag
);
1770 static inline void update_tsk_thread_flag(struct task_struct
*tsk
, int flag
,
1773 update_ti_thread_flag(task_thread_info(tsk
), flag
, value
);
1776 static inline int test_and_set_tsk_thread_flag(struct task_struct
*tsk
, int flag
)
1778 return test_and_set_ti_thread_flag(task_thread_info(tsk
), flag
);
1781 static inline int test_and_clear_tsk_thread_flag(struct task_struct
*tsk
, int flag
)
1783 return test_and_clear_ti_thread_flag(task_thread_info(tsk
), flag
);
1786 static inline int test_tsk_thread_flag(struct task_struct
*tsk
, int flag
)
1788 return test_ti_thread_flag(task_thread_info(tsk
), flag
);
1791 static inline void set_tsk_need_resched(struct task_struct
*tsk
)
1793 set_tsk_thread_flag(tsk
,TIF_NEED_RESCHED
);
1796 static inline void clear_tsk_need_resched(struct task_struct
*tsk
)
1798 clear_tsk_thread_flag(tsk
,TIF_NEED_RESCHED
);
1801 static inline int test_tsk_need_resched(struct task_struct
*tsk
)
1803 return unlikely(test_tsk_thread_flag(tsk
,TIF_NEED_RESCHED
));
1807 * cond_resched() and cond_resched_lock(): latency reduction via
1808 * explicit rescheduling in places that are safe. The return
1809 * value indicates whether a reschedule was done in fact.
1810 * cond_resched_lock() will drop the spinlock before scheduling,
1812 #ifndef CONFIG_PREEMPTION
1813 extern int _cond_resched(void);
1815 static inline int _cond_resched(void) { return 0; }
1818 #define cond_resched() ({ \
1819 ___might_sleep(__FILE__, __LINE__, 0); \
1823 extern int __cond_resched_lock(spinlock_t
*lock
);
1825 #define cond_resched_lock(lock) ({ \
1826 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
1827 __cond_resched_lock(lock); \
1830 static inline void cond_resched_rcu(void)
1832 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
1840 * Does a critical section need to be broken due to another
1841 * task waiting?: (technically does not depend on CONFIG_PREEMPTION,
1842 * but a general need for low latency)
1844 static inline int spin_needbreak(spinlock_t
*lock
)
1846 #ifdef CONFIG_PREEMPTION
1847 return spin_is_contended(lock
);
1853 static __always_inline
bool need_resched(void)
1855 return unlikely(tif_need_resched());
1859 * Wrappers for p->thread_info->cpu access. No-op on UP.
1863 static inline unsigned int task_cpu(const struct task_struct
*p
)
1865 #ifdef CONFIG_THREAD_INFO_IN_TASK
1866 return READ_ONCE(p
->cpu
);
1868 return READ_ONCE(task_thread_info(p
)->cpu
);
1872 extern void set_task_cpu(struct task_struct
*p
, unsigned int cpu
);
1876 static inline unsigned int task_cpu(const struct task_struct
*p
)
1881 static inline void set_task_cpu(struct task_struct
*p
, unsigned int cpu
)
1885 #endif /* CONFIG_SMP */
1888 * In order to reduce various lock holder preemption latencies provide an
1889 * interface to see if a vCPU is currently running or not.
1891 * This allows us to terminate optimistic spin loops and block, analogous to
1892 * the native optimistic spin heuristic of testing if the lock owner task is
1895 #ifndef vcpu_is_preempted
1896 static inline bool vcpu_is_preempted(int cpu
)
1902 extern long sched_setaffinity(pid_t pid
, const struct cpumask
*new_mask
);
1903 extern long sched_getaffinity(pid_t pid
, struct cpumask
*mask
);
1905 #ifndef TASK_SIZE_OF
1906 #define TASK_SIZE_OF(tsk) TASK_SIZE
1912 * Map the event mask on the user-space ABI enum rseq_cs_flags
1913 * for direct mask checks.
1915 enum rseq_event_mask_bits
{
1916 RSEQ_EVENT_PREEMPT_BIT
= RSEQ_CS_FLAG_NO_RESTART_ON_PREEMPT_BIT
,
1917 RSEQ_EVENT_SIGNAL_BIT
= RSEQ_CS_FLAG_NO_RESTART_ON_SIGNAL_BIT
,
1918 RSEQ_EVENT_MIGRATE_BIT
= RSEQ_CS_FLAG_NO_RESTART_ON_MIGRATE_BIT
,
1921 enum rseq_event_mask
{
1922 RSEQ_EVENT_PREEMPT
= (1U << RSEQ_EVENT_PREEMPT_BIT
),
1923 RSEQ_EVENT_SIGNAL
= (1U << RSEQ_EVENT_SIGNAL_BIT
),
1924 RSEQ_EVENT_MIGRATE
= (1U << RSEQ_EVENT_MIGRATE_BIT
),
1927 static inline void rseq_set_notify_resume(struct task_struct
*t
)
1930 set_tsk_thread_flag(t
, TIF_NOTIFY_RESUME
);
1933 void __rseq_handle_notify_resume(struct ksignal
*sig
, struct pt_regs
*regs
);
1935 static inline void rseq_handle_notify_resume(struct ksignal
*ksig
,
1936 struct pt_regs
*regs
)
1939 __rseq_handle_notify_resume(ksig
, regs
);
1942 static inline void rseq_signal_deliver(struct ksignal
*ksig
,
1943 struct pt_regs
*regs
)
1946 __set_bit(RSEQ_EVENT_SIGNAL_BIT
, ¤t
->rseq_event_mask
);
1948 rseq_handle_notify_resume(ksig
, regs
);
1951 /* rseq_preempt() requires preemption to be disabled. */
1952 static inline void rseq_preempt(struct task_struct
*t
)
1954 __set_bit(RSEQ_EVENT_PREEMPT_BIT
, &t
->rseq_event_mask
);
1955 rseq_set_notify_resume(t
);
1958 /* rseq_migrate() requires preemption to be disabled. */
1959 static inline void rseq_migrate(struct task_struct
*t
)
1961 __set_bit(RSEQ_EVENT_MIGRATE_BIT
, &t
->rseq_event_mask
);
1962 rseq_set_notify_resume(t
);
1966 * If parent process has a registered restartable sequences area, the
1967 * child inherits. Unregister rseq for a clone with CLONE_VM set.
1969 static inline void rseq_fork(struct task_struct
*t
, unsigned long clone_flags
)
1971 if (clone_flags
& CLONE_VM
) {
1974 t
->rseq_event_mask
= 0;
1976 t
->rseq
= current
->rseq
;
1977 t
->rseq_sig
= current
->rseq_sig
;
1978 t
->rseq_event_mask
= current
->rseq_event_mask
;
1982 static inline void rseq_execve(struct task_struct
*t
)
1986 t
->rseq_event_mask
= 0;
1991 static inline void rseq_set_notify_resume(struct task_struct
*t
)
1994 static inline void rseq_handle_notify_resume(struct ksignal
*ksig
,
1995 struct pt_regs
*regs
)
1998 static inline void rseq_signal_deliver(struct ksignal
*ksig
,
1999 struct pt_regs
*regs
)
2002 static inline void rseq_preempt(struct task_struct
*t
)
2005 static inline void rseq_migrate(struct task_struct
*t
)
2008 static inline void rseq_fork(struct task_struct
*t
, unsigned long clone_flags
)
2011 static inline void rseq_execve(struct task_struct
*t
)
2017 void __exit_umh(struct task_struct
*tsk
);
2019 static inline void exit_umh(struct task_struct
*tsk
)
2021 if (unlikely(tsk
->flags
& PF_UMH
))
2025 #ifdef CONFIG_DEBUG_RSEQ
2027 void rseq_syscall(struct pt_regs
*regs
);
2031 static inline void rseq_syscall(struct pt_regs
*regs
)
2037 const struct sched_avg
*sched_trace_cfs_rq_avg(struct cfs_rq
*cfs_rq
);
2038 char *sched_trace_cfs_rq_path(struct cfs_rq
*cfs_rq
, char *str
, int len
);
2039 int sched_trace_cfs_rq_cpu(struct cfs_rq
*cfs_rq
);
2041 const struct sched_avg
*sched_trace_rq_avg_rt(struct rq
*rq
);
2042 const struct sched_avg
*sched_trace_rq_avg_dl(struct rq
*rq
);
2043 const struct sched_avg
*sched_trace_rq_avg_irq(struct rq
*rq
);
2045 int sched_trace_rq_cpu(struct rq
*rq
);
2047 const struct cpumask
*sched_trace_rd_span(struct root_domain
*rd
);