Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#ifndef _LINUX_SCHED_H
2#define _LINUX_SCHED_H
3
4#include <uapi/linux/sched.h>
5
6#include <linux/sched/prio.h>
7
8
9struct sched_param {
10 int sched_priority;
11};
12
13#include <asm/param.h> /* for HZ */
14
15#include <linux/capability.h>
16#include <linux/threads.h>
17#include <linux/kernel.h>
18#include <linux/types.h>
19#include <linux/timex.h>
20#include <linux/jiffies.h>
21#include <linux/plist.h>
22#include <linux/rbtree.h>
23#include <linux/thread_info.h>
24#include <linux/cpumask.h>
25#include <linux/errno.h>
26#include <linux/nodemask.h>
27#include <linux/mm_types.h>
28#include <linux/preempt_mask.h>
29
30#include <asm/page.h>
31#include <asm/ptrace.h>
32#include <linux/cputime.h>
33
34#include <linux/smp.h>
35#include <linux/sem.h>
36#include <linux/shm.h>
37#include <linux/signal.h>
38#include <linux/compiler.h>
39#include <linux/completion.h>
40#include <linux/pid.h>
41#include <linux/percpu.h>
42#include <linux/topology.h>
43#include <linux/proportions.h>
44#include <linux/seccomp.h>
45#include <linux/rcupdate.h>
46#include <linux/rculist.h>
47#include <linux/rtmutex.h>
48
49#include <linux/time.h>
50#include <linux/param.h>
51#include <linux/resource.h>
52#include <linux/timer.h>
53#include <linux/hrtimer.h>
54#include <linux/task_io_accounting.h>
55#include <linux/latencytop.h>
56#include <linux/cred.h>
57#include <linux/llist.h>
58#include <linux/uidgid.h>
59#include <linux/gfp.h>
60#include <linux/magic.h>
61
62#include <asm/processor.h>
63
64#define SCHED_ATTR_SIZE_VER0 48 /* sizeof first published struct */
65
66/*
67 * Extended scheduling parameters data structure.
68 *
69 * This is needed because the original struct sched_param can not be
70 * altered without introducing ABI issues with legacy applications
71 * (e.g., in sched_getparam()).
72 *
73 * However, the possibility of specifying more than just a priority for
74 * the tasks may be useful for a wide variety of application fields, e.g.,
75 * multimedia, streaming, automation and control, and many others.
76 *
77 * This variant (sched_attr) is meant at describing a so-called
78 * sporadic time-constrained task. In such model a task is specified by:
79 * - the activation period or minimum instance inter-arrival time;
80 * - the maximum (or average, depending on the actual scheduling
81 * discipline) computation time of all instances, a.k.a. runtime;
82 * - the deadline (relative to the actual activation time) of each
83 * instance.
84 * Very briefly, a periodic (sporadic) task asks for the execution of
85 * some specific computation --which is typically called an instance--
86 * (at most) every period. Moreover, each instance typically lasts no more
87 * than the runtime and must be completed by time instant t equal to
88 * the instance activation time + the deadline.
89 *
90 * This is reflected by the actual fields of the sched_attr structure:
91 *
92 * @size size of the structure, for fwd/bwd compat.
93 *
94 * @sched_policy task's scheduling policy
95 * @sched_flags for customizing the scheduler behaviour
96 * @sched_nice task's nice value (SCHED_NORMAL/BATCH)
97 * @sched_priority task's static priority (SCHED_FIFO/RR)
98 * @sched_deadline representative of the task's deadline
99 * @sched_runtime representative of the task's runtime
100 * @sched_period representative of the task's period
101 *
102 * Given this task model, there are a multiplicity of scheduling algorithms
103 * and policies, that can be used to ensure all the tasks will make their
104 * timing constraints.
105 *
106 * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the
107 * only user of this new interface. More information about the algorithm
108 * available in the scheduling class file or in Documentation/.
109 */
110struct sched_attr {
111 u32 size;
112
113 u32 sched_policy;
114 u64 sched_flags;
115
116 /* SCHED_NORMAL, SCHED_BATCH */
117 s32 sched_nice;
118
119 /* SCHED_FIFO, SCHED_RR */
120 u32 sched_priority;
121
122 /* SCHED_DEADLINE */
123 u64 sched_runtime;
124 u64 sched_deadline;
125 u64 sched_period;
126};
127
128struct exec_domain;
129struct futex_pi_state;
130struct robust_list_head;
131struct bio_list;
132struct fs_struct;
133struct perf_event_context;
134struct blk_plug;
135struct filename;
136
137#define VMACACHE_BITS 2
138#define VMACACHE_SIZE (1U << VMACACHE_BITS)
139#define VMACACHE_MASK (VMACACHE_SIZE - 1)
140
141/*
142 * These are the constant used to fake the fixed-point load-average
143 * counting. Some notes:
144 * - 11 bit fractions expand to 22 bits by the multiplies: this gives
145 * a load-average precision of 10 bits integer + 11 bits fractional
146 * - if you want to count load-averages more often, you need more
147 * precision, or rounding will get you. With 2-second counting freq,
148 * the EXP_n values would be 1981, 2034 and 2043 if still using only
149 * 11 bit fractions.
150 */
151extern unsigned long avenrun[]; /* Load averages */
152extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
153
154#define FSHIFT 11 /* nr of bits of precision */
155#define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
156#define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */
157#define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
158#define EXP_5 2014 /* 1/exp(5sec/5min) */
159#define EXP_15 2037 /* 1/exp(5sec/15min) */
160
161#define CALC_LOAD(load,exp,n) \
162 load *= exp; \
163 load += n*(FIXED_1-exp); \
164 load >>= FSHIFT;
165
166extern unsigned long total_forks;
167extern int nr_threads;
168DECLARE_PER_CPU(unsigned long, process_counts);
169extern int nr_processes(void);
170extern unsigned long nr_running(void);
171extern bool single_task_running(void);
172extern unsigned long nr_iowait(void);
173extern unsigned long nr_iowait_cpu(int cpu);
174extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load);
175
176extern void calc_global_load(unsigned long ticks);
177extern void update_cpu_load_nohz(void);
178
179extern unsigned long get_parent_ip(unsigned long addr);
180
181extern void dump_cpu_task(int cpu);
182
183struct seq_file;
184struct cfs_rq;
185struct task_group;
186#ifdef CONFIG_SCHED_DEBUG
187extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
188extern void proc_sched_set_task(struct task_struct *p);
189extern void
190print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
191#endif
192
193/*
194 * Task state bitmask. NOTE! These bits are also
195 * encoded in fs/proc/array.c: get_task_state().
196 *
197 * We have two separate sets of flags: task->state
198 * is about runnability, while task->exit_state are
199 * about the task exiting. Confusing, but this way
200 * modifying one set can't modify the other one by
201 * mistake.
202 */
203#define TASK_RUNNING 0
204#define TASK_INTERRUPTIBLE 1
205#define TASK_UNINTERRUPTIBLE 2
206#define __TASK_STOPPED 4
207#define __TASK_TRACED 8
208/* in tsk->exit_state */
209#define EXIT_DEAD 16
210#define EXIT_ZOMBIE 32
211#define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD)
212/* in tsk->state again */
213#define TASK_DEAD 64
214#define TASK_WAKEKILL 128
215#define TASK_WAKING 256
216#define TASK_PARKED 512
217#define TASK_STATE_MAX 1024
218
219#define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWP"
220
221extern char ___assert_task_state[1 - 2*!!(
222 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
223
224/* Convenience macros for the sake of set_task_state */
225#define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
226#define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
227#define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED)
228
229/* Convenience macros for the sake of wake_up */
230#define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
231#define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
232
233/* get_task_state() */
234#define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \
235 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
236 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD)
237
238#define task_is_traced(task) ((task->state & __TASK_TRACED) != 0)
239#define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0)
240#define task_is_stopped_or_traced(task) \
241 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
242#define task_contributes_to_load(task) \
243 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
244 (task->flags & PF_FROZEN) == 0)
245
246#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
247
248#define __set_task_state(tsk, state_value) \
249 do { \
250 (tsk)->task_state_change = _THIS_IP_; \
251 (tsk)->state = (state_value); \
252 } while (0)
253#define set_task_state(tsk, state_value) \
254 do { \
255 (tsk)->task_state_change = _THIS_IP_; \
256 set_mb((tsk)->state, (state_value)); \
257 } while (0)
258
259/*
260 * set_current_state() includes a barrier so that the write of current->state
261 * is correctly serialised wrt the caller's subsequent test of whether to
262 * actually sleep:
263 *
264 * set_current_state(TASK_UNINTERRUPTIBLE);
265 * if (do_i_need_to_sleep())
266 * schedule();
267 *
268 * If the caller does not need such serialisation then use __set_current_state()
269 */
270#define __set_current_state(state_value) \
271 do { \
272 current->task_state_change = _THIS_IP_; \
273 current->state = (state_value); \
274 } while (0)
275#define set_current_state(state_value) \
276 do { \
277 current->task_state_change = _THIS_IP_; \
278 set_mb(current->state, (state_value)); \
279 } while (0)
280
281#else
282
283#define __set_task_state(tsk, state_value) \
284 do { (tsk)->state = (state_value); } while (0)
285#define set_task_state(tsk, state_value) \
286 set_mb((tsk)->state, (state_value))
287
288/*
289 * set_current_state() includes a barrier so that the write of current->state
290 * is correctly serialised wrt the caller's subsequent test of whether to
291 * actually sleep:
292 *
293 * set_current_state(TASK_UNINTERRUPTIBLE);
294 * if (do_i_need_to_sleep())
295 * schedule();
296 *
297 * If the caller does not need such serialisation then use __set_current_state()
298 */
299#define __set_current_state(state_value) \
300 do { current->state = (state_value); } while (0)
301#define set_current_state(state_value) \
302 set_mb(current->state, (state_value))
303
304#endif
305
306/* Task command name length */
307#define TASK_COMM_LEN 16
308
309#include <linux/spinlock.h>
310
311/*
312 * This serializes "schedule()" and also protects
313 * the run-queue from deletions/modifications (but
314 * _adding_ to the beginning of the run-queue has
315 * a separate lock).
316 */
317extern rwlock_t tasklist_lock;
318extern spinlock_t mmlist_lock;
319
320struct task_struct;
321
322#ifdef CONFIG_PROVE_RCU
323extern int lockdep_tasklist_lock_is_held(void);
324#endif /* #ifdef CONFIG_PROVE_RCU */
325
326extern void sched_init(void);
327extern void sched_init_smp(void);
328extern asmlinkage void schedule_tail(struct task_struct *prev);
329extern void init_idle(struct task_struct *idle, int cpu);
330extern void init_idle_bootup_task(struct task_struct *idle);
331
332extern int runqueue_is_locked(int cpu);
333
334#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
335extern void nohz_balance_enter_idle(int cpu);
336extern void set_cpu_sd_state_idle(void);
337extern int get_nohz_timer_target(int pinned);
338#else
339static inline void nohz_balance_enter_idle(int cpu) { }
340static inline void set_cpu_sd_state_idle(void) { }
341static inline int get_nohz_timer_target(int pinned)
342{
343 return smp_processor_id();
344}
345#endif
346
347/*
348 * Only dump TASK_* tasks. (0 for all tasks)
349 */
350extern void show_state_filter(unsigned long state_filter);
351
352static inline void show_state(void)
353{
354 show_state_filter(0);
355}
356
357extern void show_regs(struct pt_regs *);
358
359/*
360 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
361 * task), SP is the stack pointer of the first frame that should be shown in the back
362 * trace (or NULL if the entire call-chain of the task should be shown).
363 */
364extern void show_stack(struct task_struct *task, unsigned long *sp);
365
366extern void cpu_init (void);
367extern void trap_init(void);
368extern void update_process_times(int user);
369extern void scheduler_tick(void);
370
371extern void sched_show_task(struct task_struct *p);
372
373#ifdef CONFIG_LOCKUP_DETECTOR
374extern void touch_softlockup_watchdog(void);
375extern void touch_softlockup_watchdog_sync(void);
376extern void touch_all_softlockup_watchdogs(void);
377extern int proc_dowatchdog_thresh(struct ctl_table *table, int write,
378 void __user *buffer,
379 size_t *lenp, loff_t *ppos);
380extern unsigned int softlockup_panic;
381void lockup_detector_init(void);
382#else
383static inline void touch_softlockup_watchdog(void)
384{
385}
386static inline void touch_softlockup_watchdog_sync(void)
387{
388}
389static inline void touch_all_softlockup_watchdogs(void)
390{
391}
392static inline void lockup_detector_init(void)
393{
394}
395#endif
396
397#ifdef CONFIG_DETECT_HUNG_TASK
398void reset_hung_task_detector(void);
399#else
400static inline void reset_hung_task_detector(void)
401{
402}
403#endif
404
405/* Attach to any functions which should be ignored in wchan output. */
406#define __sched __attribute__((__section__(".sched.text")))
407
408/* Linker adds these: start and end of __sched functions */
409extern char __sched_text_start[], __sched_text_end[];
410
411/* Is this address in the __sched functions? */
412extern int in_sched_functions(unsigned long addr);
413
414#define MAX_SCHEDULE_TIMEOUT LONG_MAX
415extern signed long schedule_timeout(signed long timeout);
416extern signed long schedule_timeout_interruptible(signed long timeout);
417extern signed long schedule_timeout_killable(signed long timeout);
418extern signed long schedule_timeout_uninterruptible(signed long timeout);
419asmlinkage void schedule(void);
420extern void schedule_preempt_disabled(void);
421
422extern long io_schedule_timeout(long timeout);
423
424static inline void io_schedule(void)
425{
426 io_schedule_timeout(MAX_SCHEDULE_TIMEOUT);
427}
428
429struct nsproxy;
430struct user_namespace;
431
432#ifdef CONFIG_MMU
433extern void arch_pick_mmap_layout(struct mm_struct *mm);
434extern unsigned long
435arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
436 unsigned long, unsigned long);
437extern unsigned long
438arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
439 unsigned long len, unsigned long pgoff,
440 unsigned long flags);
441#else
442static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
443#endif
444
445#define SUID_DUMP_DISABLE 0 /* No setuid dumping */
446#define SUID_DUMP_USER 1 /* Dump as user of process */
447#define SUID_DUMP_ROOT 2 /* Dump as root */
448
449/* mm flags */
450
451/* for SUID_DUMP_* above */
452#define MMF_DUMPABLE_BITS 2
453#define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
454
455extern void set_dumpable(struct mm_struct *mm, int value);
456/*
457 * This returns the actual value of the suid_dumpable flag. For things
458 * that are using this for checking for privilege transitions, it must
459 * test against SUID_DUMP_USER rather than treating it as a boolean
460 * value.
461 */
462static inline int __get_dumpable(unsigned long mm_flags)
463{
464 return mm_flags & MMF_DUMPABLE_MASK;
465}
466
467static inline int get_dumpable(struct mm_struct *mm)
468{
469 return __get_dumpable(mm->flags);
470}
471
472/* coredump filter bits */
473#define MMF_DUMP_ANON_PRIVATE 2
474#define MMF_DUMP_ANON_SHARED 3
475#define MMF_DUMP_MAPPED_PRIVATE 4
476#define MMF_DUMP_MAPPED_SHARED 5
477#define MMF_DUMP_ELF_HEADERS 6
478#define MMF_DUMP_HUGETLB_PRIVATE 7
479#define MMF_DUMP_HUGETLB_SHARED 8
480
481#define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS
482#define MMF_DUMP_FILTER_BITS 7
483#define MMF_DUMP_FILTER_MASK \
484 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
485#define MMF_DUMP_FILTER_DEFAULT \
486 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\
487 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
488
489#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
490# define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS)
491#else
492# define MMF_DUMP_MASK_DEFAULT_ELF 0
493#endif
494 /* leave room for more dump flags */
495#define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */
496#define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */
497#define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */
498
499#define MMF_HAS_UPROBES 19 /* has uprobes */
500#define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */
501
502#define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
503
504struct sighand_struct {
505 atomic_t count;
506 struct k_sigaction action[_NSIG];
507 spinlock_t siglock;
508 wait_queue_head_t signalfd_wqh;
509};
510
511struct pacct_struct {
512 int ac_flag;
513 long ac_exitcode;
514 unsigned long ac_mem;
515 cputime_t ac_utime, ac_stime;
516 unsigned long ac_minflt, ac_majflt;
517};
518
519struct cpu_itimer {
520 cputime_t expires;
521 cputime_t incr;
522 u32 error;
523 u32 incr_error;
524};
525
526/**
527 * struct cputime - snaphsot of system and user cputime
528 * @utime: time spent in user mode
529 * @stime: time spent in system mode
530 *
531 * Gathers a generic snapshot of user and system time.
532 */
533struct cputime {
534 cputime_t utime;
535 cputime_t stime;
536};
537
538/**
539 * struct task_cputime - collected CPU time counts
540 * @utime: time spent in user mode, in &cputime_t units
541 * @stime: time spent in kernel mode, in &cputime_t units
542 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds
543 *
544 * This is an extension of struct cputime that includes the total runtime
545 * spent by the task from the scheduler point of view.
546 *
547 * As a result, this structure groups together three kinds of CPU time
548 * that are tracked for threads and thread groups. Most things considering
549 * CPU time want to group these counts together and treat all three
550 * of them in parallel.
551 */
552struct task_cputime {
553 cputime_t utime;
554 cputime_t stime;
555 unsigned long long sum_exec_runtime;
556};
557/* Alternate field names when used to cache expirations. */
558#define prof_exp stime
559#define virt_exp utime
560#define sched_exp sum_exec_runtime
561
562#define INIT_CPUTIME \
563 (struct task_cputime) { \
564 .utime = 0, \
565 .stime = 0, \
566 .sum_exec_runtime = 0, \
567 }
568
569#ifdef CONFIG_PREEMPT_COUNT
570#define PREEMPT_DISABLED (1 + PREEMPT_ENABLED)
571#else
572#define PREEMPT_DISABLED PREEMPT_ENABLED
573#endif
574
575/*
576 * Disable preemption until the scheduler is running.
577 * Reset by start_kernel()->sched_init()->init_idle().
578 *
579 * We include PREEMPT_ACTIVE to avoid cond_resched() from working
580 * before the scheduler is active -- see should_resched().
581 */
582#define INIT_PREEMPT_COUNT (PREEMPT_DISABLED + PREEMPT_ACTIVE)
583
584/**
585 * struct thread_group_cputimer - thread group interval timer counts
586 * @cputime: thread group interval timers.
587 * @running: non-zero when there are timers running and
588 * @cputime receives updates.
589 * @lock: lock for fields in this struct.
590 *
591 * This structure contains the version of task_cputime, above, that is
592 * used for thread group CPU timer calculations.
593 */
594struct thread_group_cputimer {
595 struct task_cputime cputime;
596 int running;
597 raw_spinlock_t lock;
598};
599
600#include <linux/rwsem.h>
601struct autogroup;
602
603/*
604 * NOTE! "signal_struct" does not have its own
605 * locking, because a shared signal_struct always
606 * implies a shared sighand_struct, so locking
607 * sighand_struct is always a proper superset of
608 * the locking of signal_struct.
609 */
610struct signal_struct {
611 atomic_t sigcnt;
612 atomic_t live;
613 int nr_threads;
614 struct list_head thread_head;
615
616 wait_queue_head_t wait_chldexit; /* for wait4() */
617
618 /* current thread group signal load-balancing target: */
619 struct task_struct *curr_target;
620
621 /* shared signal handling: */
622 struct sigpending shared_pending;
623
624 /* thread group exit support */
625 int group_exit_code;
626 /* overloaded:
627 * - notify group_exit_task when ->count is equal to notify_count
628 * - everyone except group_exit_task is stopped during signal delivery
629 * of fatal signals, group_exit_task processes the signal.
630 */
631 int notify_count;
632 struct task_struct *group_exit_task;
633
634 /* thread group stop support, overloads group_exit_code too */
635 int group_stop_count;
636 unsigned int flags; /* see SIGNAL_* flags below */
637
638 /*
639 * PR_SET_CHILD_SUBREAPER marks a process, like a service
640 * manager, to re-parent orphan (double-forking) child processes
641 * to this process instead of 'init'. The service manager is
642 * able to receive SIGCHLD signals and is able to investigate
643 * the process until it calls wait(). All children of this
644 * process will inherit a flag if they should look for a
645 * child_subreaper process at exit.
646 */
647 unsigned int is_child_subreaper:1;
648 unsigned int has_child_subreaper:1;
649
650 /* POSIX.1b Interval Timers */
651 int posix_timer_id;
652 struct list_head posix_timers;
653
654 /* ITIMER_REAL timer for the process */
655 struct hrtimer real_timer;
656 struct pid *leader_pid;
657 ktime_t it_real_incr;
658
659 /*
660 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
661 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
662 * values are defined to 0 and 1 respectively
663 */
664 struct cpu_itimer it[2];
665
666 /*
667 * Thread group totals for process CPU timers.
668 * See thread_group_cputimer(), et al, for details.
669 */
670 struct thread_group_cputimer cputimer;
671
672 /* Earliest-expiration cache. */
673 struct task_cputime cputime_expires;
674
675 struct list_head cpu_timers[3];
676
677 struct pid *tty_old_pgrp;
678
679 /* boolean value for session group leader */
680 int leader;
681
682 struct tty_struct *tty; /* NULL if no tty */
683
684#ifdef CONFIG_SCHED_AUTOGROUP
685 struct autogroup *autogroup;
686#endif
687 /*
688 * Cumulative resource counters for dead threads in the group,
689 * and for reaped dead child processes forked by this group.
690 * Live threads maintain their own counters and add to these
691 * in __exit_signal, except for the group leader.
692 */
693 seqlock_t stats_lock;
694 cputime_t utime, stime, cutime, cstime;
695 cputime_t gtime;
696 cputime_t cgtime;
697#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
698 struct cputime prev_cputime;
699#endif
700 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
701 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
702 unsigned long inblock, oublock, cinblock, coublock;
703 unsigned long maxrss, cmaxrss;
704 struct task_io_accounting ioac;
705
706 /*
707 * Cumulative ns of schedule CPU time fo dead threads in the
708 * group, not including a zombie group leader, (This only differs
709 * from jiffies_to_ns(utime + stime) if sched_clock uses something
710 * other than jiffies.)
711 */
712 unsigned long long sum_sched_runtime;
713
714 /*
715 * We don't bother to synchronize most readers of this at all,
716 * because there is no reader checking a limit that actually needs
717 * to get both rlim_cur and rlim_max atomically, and either one
718 * alone is a single word that can safely be read normally.
719 * getrlimit/setrlimit use task_lock(current->group_leader) to
720 * protect this instead of the siglock, because they really
721 * have no need to disable irqs.
722 */
723 struct rlimit rlim[RLIM_NLIMITS];
724
725#ifdef CONFIG_BSD_PROCESS_ACCT
726 struct pacct_struct pacct; /* per-process accounting information */
727#endif
728#ifdef CONFIG_TASKSTATS
729 struct taskstats *stats;
730#endif
731#ifdef CONFIG_AUDIT
732 unsigned audit_tty;
733 unsigned audit_tty_log_passwd;
734 struct tty_audit_buf *tty_audit_buf;
735#endif
736#ifdef CONFIG_CGROUPS
737 /*
738 * group_rwsem prevents new tasks from entering the threadgroup and
739 * member tasks from exiting,a more specifically, setting of
740 * PF_EXITING. fork and exit paths are protected with this rwsem
741 * using threadgroup_change_begin/end(). Users which require
742 * threadgroup to remain stable should use threadgroup_[un]lock()
743 * which also takes care of exec path. Currently, cgroup is the
744 * only user.
745 */
746 struct rw_semaphore group_rwsem;
747#endif
748
749 oom_flags_t oom_flags;
750 short oom_score_adj; /* OOM kill score adjustment */
751 short oom_score_adj_min; /* OOM kill score adjustment min value.
752 * Only settable by CAP_SYS_RESOURCE. */
753
754 struct mutex cred_guard_mutex; /* guard against foreign influences on
755 * credential calculations
756 * (notably. ptrace) */
757};
758
759/*
760 * Bits in flags field of signal_struct.
761 */
762#define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */
763#define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */
764#define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */
765#define SIGNAL_GROUP_COREDUMP 0x00000008 /* coredump in progress */
766/*
767 * Pending notifications to parent.
768 */
769#define SIGNAL_CLD_STOPPED 0x00000010
770#define SIGNAL_CLD_CONTINUED 0x00000020
771#define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
772
773#define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */
774
775/* If true, all threads except ->group_exit_task have pending SIGKILL */
776static inline int signal_group_exit(const struct signal_struct *sig)
777{
778 return (sig->flags & SIGNAL_GROUP_EXIT) ||
779 (sig->group_exit_task != NULL);
780}
781
782/*
783 * Some day this will be a full-fledged user tracking system..
784 */
785struct user_struct {
786 atomic_t __count; /* reference count */
787 atomic_t processes; /* How many processes does this user have? */
788 atomic_t sigpending; /* How many pending signals does this user have? */
789#ifdef CONFIG_INOTIFY_USER
790 atomic_t inotify_watches; /* How many inotify watches does this user have? */
791 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */
792#endif
793#ifdef CONFIG_FANOTIFY
794 atomic_t fanotify_listeners;
795#endif
796#ifdef CONFIG_EPOLL
797 atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
798#endif
799#ifdef CONFIG_POSIX_MQUEUE
800 /* protected by mq_lock */
801 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
802#endif
803 unsigned long locked_shm; /* How many pages of mlocked shm ? */
804
805#ifdef CONFIG_KEYS
806 struct key *uid_keyring; /* UID specific keyring */
807 struct key *session_keyring; /* UID's default session keyring */
808#endif
809
810 /* Hash table maintenance information */
811 struct hlist_node uidhash_node;
812 kuid_t uid;
813
814#ifdef CONFIG_PERF_EVENTS
815 atomic_long_t locked_vm;
816#endif
817};
818
819extern int uids_sysfs_init(void);
820
821extern struct user_struct *find_user(kuid_t);
822
823extern struct user_struct root_user;
824#define INIT_USER (&root_user)
825
826
827struct backing_dev_info;
828struct reclaim_state;
829
830#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
831struct sched_info {
832 /* cumulative counters */
833 unsigned long pcount; /* # of times run on this cpu */
834 unsigned long long run_delay; /* time spent waiting on a runqueue */
835
836 /* timestamps */
837 unsigned long long last_arrival,/* when we last ran on a cpu */
838 last_queued; /* when we were last queued to run */
839};
840#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
841
842#ifdef CONFIG_TASK_DELAY_ACCT
843struct task_delay_info {
844 spinlock_t lock;
845 unsigned int flags; /* Private per-task flags */
846
847 /* For each stat XXX, add following, aligned appropriately
848 *
849 * struct timespec XXX_start, XXX_end;
850 * u64 XXX_delay;
851 * u32 XXX_count;
852 *
853 * Atomicity of updates to XXX_delay, XXX_count protected by
854 * single lock above (split into XXX_lock if contention is an issue).
855 */
856
857 /*
858 * XXX_count is incremented on every XXX operation, the delay
859 * associated with the operation is added to XXX_delay.
860 * XXX_delay contains the accumulated delay time in nanoseconds.
861 */
862 u64 blkio_start; /* Shared by blkio, swapin */
863 u64 blkio_delay; /* wait for sync block io completion */
864 u64 swapin_delay; /* wait for swapin block io completion */
865 u32 blkio_count; /* total count of the number of sync block */
866 /* io operations performed */
867 u32 swapin_count; /* total count of the number of swapin block */
868 /* io operations performed */
869
870 u64 freepages_start;
871 u64 freepages_delay; /* wait for memory reclaim */
872 u32 freepages_count; /* total count of memory reclaim */
873};
874#endif /* CONFIG_TASK_DELAY_ACCT */
875
876static inline int sched_info_on(void)
877{
878#ifdef CONFIG_SCHEDSTATS
879 return 1;
880#elif defined(CONFIG_TASK_DELAY_ACCT)
881 extern int delayacct_on;
882 return delayacct_on;
883#else
884 return 0;
885#endif
886}
887
888enum cpu_idle_type {
889 CPU_IDLE,
890 CPU_NOT_IDLE,
891 CPU_NEWLY_IDLE,
892 CPU_MAX_IDLE_TYPES
893};
894
895/*
896 * Increase resolution of cpu_capacity calculations
897 */
898#define SCHED_CAPACITY_SHIFT 10
899#define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT)
900
901/*
902 * sched-domains (multiprocessor balancing) declarations:
903 */
904#ifdef CONFIG_SMP
905#define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */
906#define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */
907#define SD_BALANCE_EXEC 0x0004 /* Balance on exec */
908#define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */
909#define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */
910#define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */
911#define SD_SHARE_CPUCAPACITY 0x0080 /* Domain members share cpu power */
912#define SD_SHARE_POWERDOMAIN 0x0100 /* Domain members share power domain */
913#define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */
914#define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */
915#define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */
916#define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */
917#define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */
918#define SD_NUMA 0x4000 /* cross-node balancing */
919
920#ifdef CONFIG_SCHED_SMT
921static inline int cpu_smt_flags(void)
922{
923 return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES;
924}
925#endif
926
927#ifdef CONFIG_SCHED_MC
928static inline int cpu_core_flags(void)
929{
930 return SD_SHARE_PKG_RESOURCES;
931}
932#endif
933
934#ifdef CONFIG_NUMA
935static inline int cpu_numa_flags(void)
936{
937 return SD_NUMA;
938}
939#endif
940
941struct sched_domain_attr {
942 int relax_domain_level;
943};
944
945#define SD_ATTR_INIT (struct sched_domain_attr) { \
946 .relax_domain_level = -1, \
947}
948
949extern int sched_domain_level_max;
950
951struct sched_group;
952
953struct sched_domain {
954 /* These fields must be setup */
955 struct sched_domain *parent; /* top domain must be null terminated */
956 struct sched_domain *child; /* bottom domain must be null terminated */
957 struct sched_group *groups; /* the balancing groups of the domain */
958 unsigned long min_interval; /* Minimum balance interval ms */
959 unsigned long max_interval; /* Maximum balance interval ms */
960 unsigned int busy_factor; /* less balancing by factor if busy */
961 unsigned int imbalance_pct; /* No balance until over watermark */
962 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */
963 unsigned int busy_idx;
964 unsigned int idle_idx;
965 unsigned int newidle_idx;
966 unsigned int wake_idx;
967 unsigned int forkexec_idx;
968 unsigned int smt_gain;
969
970 int nohz_idle; /* NOHZ IDLE status */
971 int flags; /* See SD_* */
972 int level;
973
974 /* Runtime fields. */
975 unsigned long last_balance; /* init to jiffies. units in jiffies */
976 unsigned int balance_interval; /* initialise to 1. units in ms. */
977 unsigned int nr_balance_failed; /* initialise to 0 */
978
979 /* idle_balance() stats */
980 u64 max_newidle_lb_cost;
981 unsigned long next_decay_max_lb_cost;
982
983#ifdef CONFIG_SCHEDSTATS
984 /* load_balance() stats */
985 unsigned int lb_count[CPU_MAX_IDLE_TYPES];
986 unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
987 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
988 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
989 unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
990 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
991 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
992 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
993
994 /* Active load balancing */
995 unsigned int alb_count;
996 unsigned int alb_failed;
997 unsigned int alb_pushed;
998
999 /* SD_BALANCE_EXEC stats */
1000 unsigned int sbe_count;
1001 unsigned int sbe_balanced;
1002 unsigned int sbe_pushed;
1003
1004 /* SD_BALANCE_FORK stats */
1005 unsigned int sbf_count;
1006 unsigned int sbf_balanced;
1007 unsigned int sbf_pushed;
1008
1009 /* try_to_wake_up() stats */
1010 unsigned int ttwu_wake_remote;
1011 unsigned int ttwu_move_affine;
1012 unsigned int ttwu_move_balance;
1013#endif
1014#ifdef CONFIG_SCHED_DEBUG
1015 char *name;
1016#endif
1017 union {
1018 void *private; /* used during construction */
1019 struct rcu_head rcu; /* used during destruction */
1020 };
1021
1022 unsigned int span_weight;
1023 /*
1024 * Span of all CPUs in this domain.
1025 *
1026 * NOTE: this field is variable length. (Allocated dynamically
1027 * by attaching extra space to the end of the structure,
1028 * depending on how many CPUs the kernel has booted up with)
1029 */
1030 unsigned long span[0];
1031};
1032
1033static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
1034{
1035 return to_cpumask(sd->span);
1036}
1037
1038extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1039 struct sched_domain_attr *dattr_new);
1040
1041/* Allocate an array of sched domains, for partition_sched_domains(). */
1042cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
1043void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
1044
1045bool cpus_share_cache(int this_cpu, int that_cpu);
1046
1047typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
1048typedef int (*sched_domain_flags_f)(void);
1049
1050#define SDTL_OVERLAP 0x01
1051
1052struct sd_data {
1053 struct sched_domain **__percpu sd;
1054 struct sched_group **__percpu sg;
1055 struct sched_group_capacity **__percpu sgc;
1056};
1057
1058struct sched_domain_topology_level {
1059 sched_domain_mask_f mask;
1060 sched_domain_flags_f sd_flags;
1061 int flags;
1062 int numa_level;
1063 struct sd_data data;
1064#ifdef CONFIG_SCHED_DEBUG
1065 char *name;
1066#endif
1067};
1068
1069extern struct sched_domain_topology_level *sched_domain_topology;
1070
1071extern void set_sched_topology(struct sched_domain_topology_level *tl);
1072extern void wake_up_if_idle(int cpu);
1073
1074#ifdef CONFIG_SCHED_DEBUG
1075# define SD_INIT_NAME(type) .name = #type
1076#else
1077# define SD_INIT_NAME(type)
1078#endif
1079
1080#else /* CONFIG_SMP */
1081
1082struct sched_domain_attr;
1083
1084static inline void
1085partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1086 struct sched_domain_attr *dattr_new)
1087{
1088}
1089
1090static inline bool cpus_share_cache(int this_cpu, int that_cpu)
1091{
1092 return true;
1093}
1094
1095#endif /* !CONFIG_SMP */
1096
1097
1098struct io_context; /* See blkdev.h */
1099
1100
1101#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1102extern void prefetch_stack(struct task_struct *t);
1103#else
1104static inline void prefetch_stack(struct task_struct *t) { }
1105#endif
1106
1107struct audit_context; /* See audit.c */
1108struct mempolicy;
1109struct pipe_inode_info;
1110struct uts_namespace;
1111
1112struct load_weight {
1113 unsigned long weight;
1114 u32 inv_weight;
1115};
1116
1117struct sched_avg {
1118 /*
1119 * These sums represent an infinite geometric series and so are bound
1120 * above by 1024/(1-y). Thus we only need a u32 to store them for all
1121 * choices of y < 1-2^(-32)*1024.
1122 */
1123 u32 runnable_avg_sum, runnable_avg_period;
1124 u64 last_runnable_update;
1125 s64 decay_count;
1126 unsigned long load_avg_contrib;
1127};
1128
1129#ifdef CONFIG_SCHEDSTATS
1130struct sched_statistics {
1131 u64 wait_start;
1132 u64 wait_max;
1133 u64 wait_count;
1134 u64 wait_sum;
1135 u64 iowait_count;
1136 u64 iowait_sum;
1137
1138 u64 sleep_start;
1139 u64 sleep_max;
1140 s64 sum_sleep_runtime;
1141
1142 u64 block_start;
1143 u64 block_max;
1144 u64 exec_max;
1145 u64 slice_max;
1146
1147 u64 nr_migrations_cold;
1148 u64 nr_failed_migrations_affine;
1149 u64 nr_failed_migrations_running;
1150 u64 nr_failed_migrations_hot;
1151 u64 nr_forced_migrations;
1152
1153 u64 nr_wakeups;
1154 u64 nr_wakeups_sync;
1155 u64 nr_wakeups_migrate;
1156 u64 nr_wakeups_local;
1157 u64 nr_wakeups_remote;
1158 u64 nr_wakeups_affine;
1159 u64 nr_wakeups_affine_attempts;
1160 u64 nr_wakeups_passive;
1161 u64 nr_wakeups_idle;
1162};
1163#endif
1164
1165struct sched_entity {
1166 struct load_weight load; /* for load-balancing */
1167 struct rb_node run_node;
1168 struct list_head group_node;
1169 unsigned int on_rq;
1170
1171 u64 exec_start;
1172 u64 sum_exec_runtime;
1173 u64 vruntime;
1174 u64 prev_sum_exec_runtime;
1175
1176 u64 nr_migrations;
1177
1178#ifdef CONFIG_SCHEDSTATS
1179 struct sched_statistics statistics;
1180#endif
1181
1182#ifdef CONFIG_FAIR_GROUP_SCHED
1183 int depth;
1184 struct sched_entity *parent;
1185 /* rq on which this entity is (to be) queued: */
1186 struct cfs_rq *cfs_rq;
1187 /* rq "owned" by this entity/group: */
1188 struct cfs_rq *my_q;
1189#endif
1190
1191#ifdef CONFIG_SMP
1192 /* Per-entity load-tracking */
1193 struct sched_avg avg;
1194#endif
1195};
1196
1197struct sched_rt_entity {
1198 struct list_head run_list;
1199 unsigned long timeout;
1200 unsigned long watchdog_stamp;
1201 unsigned int time_slice;
1202
1203 struct sched_rt_entity *back;
1204#ifdef CONFIG_RT_GROUP_SCHED
1205 struct sched_rt_entity *parent;
1206 /* rq on which this entity is (to be) queued: */
1207 struct rt_rq *rt_rq;
1208 /* rq "owned" by this entity/group: */
1209 struct rt_rq *my_q;
1210#endif
1211};
1212
1213struct sched_dl_entity {
1214 struct rb_node rb_node;
1215
1216 /*
1217 * Original scheduling parameters. Copied here from sched_attr
1218 * during sched_setattr(), they will remain the same until
1219 * the next sched_setattr().
1220 */
1221 u64 dl_runtime; /* maximum runtime for each instance */
1222 u64 dl_deadline; /* relative deadline of each instance */
1223 u64 dl_period; /* separation of two instances (period) */
1224 u64 dl_bw; /* dl_runtime / dl_deadline */
1225
1226 /*
1227 * Actual scheduling parameters. Initialized with the values above,
1228 * they are continously updated during task execution. Note that
1229 * the remaining runtime could be < 0 in case we are in overrun.
1230 */
1231 s64 runtime; /* remaining runtime for this instance */
1232 u64 deadline; /* absolute deadline for this instance */
1233 unsigned int flags; /* specifying the scheduler behaviour */
1234
1235 /*
1236 * Some bool flags:
1237 *
1238 * @dl_throttled tells if we exhausted the runtime. If so, the
1239 * task has to wait for a replenishment to be performed at the
1240 * next firing of dl_timer.
1241 *
1242 * @dl_new tells if a new instance arrived. If so we must
1243 * start executing it with full runtime and reset its absolute
1244 * deadline;
1245 *
1246 * @dl_boosted tells if we are boosted due to DI. If so we are
1247 * outside bandwidth enforcement mechanism (but only until we
1248 * exit the critical section);
1249 *
1250 * @dl_yielded tells if task gave up the cpu before consuming
1251 * all its available runtime during the last job.
1252 */
1253 int dl_throttled, dl_new, dl_boosted, dl_yielded;
1254
1255 /*
1256 * Bandwidth enforcement timer. Each -deadline task has its
1257 * own bandwidth to be enforced, thus we need one timer per task.
1258 */
1259 struct hrtimer dl_timer;
1260};
1261
1262union rcu_special {
1263 struct {
1264 bool blocked;
1265 bool need_qs;
1266 } b;
1267 short s;
1268};
1269struct rcu_node;
1270
1271enum perf_event_task_context {
1272 perf_invalid_context = -1,
1273 perf_hw_context = 0,
1274 perf_sw_context,
1275 perf_nr_task_contexts,
1276};
1277
1278struct task_struct {
1279 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
1280 void *stack;
1281 atomic_t usage;
1282 unsigned int flags; /* per process flags, defined below */
1283 unsigned int ptrace;
1284
1285#ifdef CONFIG_SMP
1286 struct llist_node wake_entry;
1287 int on_cpu;
1288 struct task_struct *last_wakee;
1289 unsigned long wakee_flips;
1290 unsigned long wakee_flip_decay_ts;
1291
1292 int wake_cpu;
1293#endif
1294 int on_rq;
1295
1296 int prio, static_prio, normal_prio;
1297 unsigned int rt_priority;
1298 const struct sched_class *sched_class;
1299 struct sched_entity se;
1300 struct sched_rt_entity rt;
1301#ifdef CONFIG_CGROUP_SCHED
1302 struct task_group *sched_task_group;
1303#endif
1304 struct sched_dl_entity dl;
1305
1306#ifdef CONFIG_PREEMPT_NOTIFIERS
1307 /* list of struct preempt_notifier: */
1308 struct hlist_head preempt_notifiers;
1309#endif
1310
1311#ifdef CONFIG_BLK_DEV_IO_TRACE
1312 unsigned int btrace_seq;
1313#endif
1314
1315 unsigned int policy;
1316 int nr_cpus_allowed;
1317 cpumask_t cpus_allowed;
1318
1319#ifdef CONFIG_PREEMPT_RCU
1320 int rcu_read_lock_nesting;
1321 union rcu_special rcu_read_unlock_special;
1322 struct list_head rcu_node_entry;
1323#endif /* #ifdef CONFIG_PREEMPT_RCU */
1324#ifdef CONFIG_PREEMPT_RCU
1325 struct rcu_node *rcu_blocked_node;
1326#endif /* #ifdef CONFIG_PREEMPT_RCU */
1327#ifdef CONFIG_TASKS_RCU
1328 unsigned long rcu_tasks_nvcsw;
1329 bool rcu_tasks_holdout;
1330 struct list_head rcu_tasks_holdout_list;
1331 int rcu_tasks_idle_cpu;
1332#endif /* #ifdef CONFIG_TASKS_RCU */
1333
1334#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1335 struct sched_info sched_info;
1336#endif
1337
1338 struct list_head tasks;
1339#ifdef CONFIG_SMP
1340 struct plist_node pushable_tasks;
1341 struct rb_node pushable_dl_tasks;
1342#endif
1343
1344 struct mm_struct *mm, *active_mm;
1345#ifdef CONFIG_COMPAT_BRK
1346 unsigned brk_randomized:1;
1347#endif
1348 /* per-thread vma caching */
1349 u32 vmacache_seqnum;
1350 struct vm_area_struct *vmacache[VMACACHE_SIZE];
1351#if defined(SPLIT_RSS_COUNTING)
1352 struct task_rss_stat rss_stat;
1353#endif
1354/* task state */
1355 int exit_state;
1356 int exit_code, exit_signal;
1357 int pdeath_signal; /* The signal sent when the parent dies */
1358 unsigned int jobctl; /* JOBCTL_*, siglock protected */
1359
1360 /* Used for emulating ABI behavior of previous Linux versions */
1361 unsigned int personality;
1362
1363 unsigned in_execve:1; /* Tell the LSMs that the process is doing an
1364 * execve */
1365 unsigned in_iowait:1;
1366
1367 /* Revert to default priority/policy when forking */
1368 unsigned sched_reset_on_fork:1;
1369 unsigned sched_contributes_to_load:1;
1370
1371#ifdef CONFIG_MEMCG_KMEM
1372 unsigned memcg_kmem_skip_account:1;
1373#endif
1374
1375 unsigned long atomic_flags; /* Flags needing atomic access. */
1376
1377 struct restart_block restart_block;
1378
1379 pid_t pid;
1380 pid_t tgid;
1381
1382#ifdef CONFIG_CC_STACKPROTECTOR
1383 /* Canary value for the -fstack-protector gcc feature */
1384 unsigned long stack_canary;
1385#endif
1386 /*
1387 * pointers to (original) parent process, youngest child, younger sibling,
1388 * older sibling, respectively. (p->father can be replaced with
1389 * p->real_parent->pid)
1390 */
1391 struct task_struct __rcu *real_parent; /* real parent process */
1392 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */
1393 /*
1394 * children/sibling forms the list of my natural children
1395 */
1396 struct list_head children; /* list of my children */
1397 struct list_head sibling; /* linkage in my parent's children list */
1398 struct task_struct *group_leader; /* threadgroup leader */
1399
1400 /*
1401 * ptraced is the list of tasks this task is using ptrace on.
1402 * This includes both natural children and PTRACE_ATTACH targets.
1403 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1404 */
1405 struct list_head ptraced;
1406 struct list_head ptrace_entry;
1407
1408 /* PID/PID hash table linkage. */
1409 struct pid_link pids[PIDTYPE_MAX];
1410 struct list_head thread_group;
1411 struct list_head thread_node;
1412
1413 struct completion *vfork_done; /* for vfork() */
1414 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
1415 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
1416
1417 cputime_t utime, stime, utimescaled, stimescaled;
1418 cputime_t gtime;
1419#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
1420 struct cputime prev_cputime;
1421#endif
1422#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1423 seqlock_t vtime_seqlock;
1424 unsigned long long vtime_snap;
1425 enum {
1426 VTIME_SLEEPING = 0,
1427 VTIME_USER,
1428 VTIME_SYS,
1429 } vtime_snap_whence;
1430#endif
1431 unsigned long nvcsw, nivcsw; /* context switch counts */
1432 u64 start_time; /* monotonic time in nsec */
1433 u64 real_start_time; /* boot based time in nsec */
1434/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1435 unsigned long min_flt, maj_flt;
1436
1437 struct task_cputime cputime_expires;
1438 struct list_head cpu_timers[3];
1439
1440/* process credentials */
1441 const struct cred __rcu *real_cred; /* objective and real subjective task
1442 * credentials (COW) */
1443 const struct cred __rcu *cred; /* effective (overridable) subjective task
1444 * credentials (COW) */
1445 char comm[TASK_COMM_LEN]; /* executable name excluding path
1446 - access with [gs]et_task_comm (which lock
1447 it with task_lock())
1448 - initialized normally by setup_new_exec */
1449/* file system info */
1450 int link_count, total_link_count;
1451#ifdef CONFIG_SYSVIPC
1452/* ipc stuff */
1453 struct sysv_sem sysvsem;
1454 struct sysv_shm sysvshm;
1455#endif
1456#ifdef CONFIG_DETECT_HUNG_TASK
1457/* hung task detection */
1458 unsigned long last_switch_count;
1459#endif
1460/* CPU-specific state of this task */
1461 struct thread_struct thread;
1462/* filesystem information */
1463 struct fs_struct *fs;
1464/* open file information */
1465 struct files_struct *files;
1466/* namespaces */
1467 struct nsproxy *nsproxy;
1468/* signal handlers */
1469 struct signal_struct *signal;
1470 struct sighand_struct *sighand;
1471
1472 sigset_t blocked, real_blocked;
1473 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
1474 struct sigpending pending;
1475
1476 unsigned long sas_ss_sp;
1477 size_t sas_ss_size;
1478 int (*notifier)(void *priv);
1479 void *notifier_data;
1480 sigset_t *notifier_mask;
1481 struct callback_head *task_works;
1482
1483 struct audit_context *audit_context;
1484#ifdef CONFIG_AUDITSYSCALL
1485 kuid_t loginuid;
1486 unsigned int sessionid;
1487#endif
1488 struct seccomp seccomp;
1489
1490/* Thread group tracking */
1491 u32 parent_exec_id;
1492 u32 self_exec_id;
1493/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1494 * mempolicy */
1495 spinlock_t alloc_lock;
1496
1497 /* Protection of the PI data structures: */
1498 raw_spinlock_t pi_lock;
1499
1500#ifdef CONFIG_RT_MUTEXES
1501 /* PI waiters blocked on a rt_mutex held by this task */
1502 struct rb_root pi_waiters;
1503 struct rb_node *pi_waiters_leftmost;
1504 /* Deadlock detection and priority inheritance handling */
1505 struct rt_mutex_waiter *pi_blocked_on;
1506#endif
1507
1508#ifdef CONFIG_DEBUG_MUTEXES
1509 /* mutex deadlock detection */
1510 struct mutex_waiter *blocked_on;
1511#endif
1512#ifdef CONFIG_TRACE_IRQFLAGS
1513 unsigned int irq_events;
1514 unsigned long hardirq_enable_ip;
1515 unsigned long hardirq_disable_ip;
1516 unsigned int hardirq_enable_event;
1517 unsigned int hardirq_disable_event;
1518 int hardirqs_enabled;
1519 int hardirq_context;
1520 unsigned long softirq_disable_ip;
1521 unsigned long softirq_enable_ip;
1522 unsigned int softirq_disable_event;
1523 unsigned int softirq_enable_event;
1524 int softirqs_enabled;
1525 int softirq_context;
1526#endif
1527#ifdef CONFIG_LOCKDEP
1528# define MAX_LOCK_DEPTH 48UL
1529 u64 curr_chain_key;
1530 int lockdep_depth;
1531 unsigned int lockdep_recursion;
1532 struct held_lock held_locks[MAX_LOCK_DEPTH];
1533 gfp_t lockdep_reclaim_gfp;
1534#endif
1535
1536/* journalling filesystem info */
1537 void *journal_info;
1538
1539/* stacked block device info */
1540 struct bio_list *bio_list;
1541
1542#ifdef CONFIG_BLOCK
1543/* stack plugging */
1544 struct blk_plug *plug;
1545#endif
1546
1547/* VM state */
1548 struct reclaim_state *reclaim_state;
1549
1550 struct backing_dev_info *backing_dev_info;
1551
1552 struct io_context *io_context;
1553
1554 unsigned long ptrace_message;
1555 siginfo_t *last_siginfo; /* For ptrace use. */
1556 struct task_io_accounting ioac;
1557#if defined(CONFIG_TASK_XACCT)
1558 u64 acct_rss_mem1; /* accumulated rss usage */
1559 u64 acct_vm_mem1; /* accumulated virtual memory usage */
1560 cputime_t acct_timexpd; /* stime + utime since last update */
1561#endif
1562#ifdef CONFIG_CPUSETS
1563 nodemask_t mems_allowed; /* Protected by alloc_lock */
1564 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */
1565 int cpuset_mem_spread_rotor;
1566 int cpuset_slab_spread_rotor;
1567#endif
1568#ifdef CONFIG_CGROUPS
1569 /* Control Group info protected by css_set_lock */
1570 struct css_set __rcu *cgroups;
1571 /* cg_list protected by css_set_lock and tsk->alloc_lock */
1572 struct list_head cg_list;
1573#endif
1574#ifdef CONFIG_FUTEX
1575 struct robust_list_head __user *robust_list;
1576#ifdef CONFIG_COMPAT
1577 struct compat_robust_list_head __user *compat_robust_list;
1578#endif
1579 struct list_head pi_state_list;
1580 struct futex_pi_state *pi_state_cache;
1581#endif
1582#ifdef CONFIG_PERF_EVENTS
1583 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1584 struct mutex perf_event_mutex;
1585 struct list_head perf_event_list;
1586#endif
1587#ifdef CONFIG_DEBUG_PREEMPT
1588 unsigned long preempt_disable_ip;
1589#endif
1590#ifdef CONFIG_NUMA
1591 struct mempolicy *mempolicy; /* Protected by alloc_lock */
1592 short il_next;
1593 short pref_node_fork;
1594#endif
1595#ifdef CONFIG_NUMA_BALANCING
1596 int numa_scan_seq;
1597 unsigned int numa_scan_period;
1598 unsigned int numa_scan_period_max;
1599 int numa_preferred_nid;
1600 unsigned long numa_migrate_retry;
1601 u64 node_stamp; /* migration stamp */
1602 u64 last_task_numa_placement;
1603 u64 last_sum_exec_runtime;
1604 struct callback_head numa_work;
1605
1606 struct list_head numa_entry;
1607 struct numa_group *numa_group;
1608
1609 /*
1610 * numa_faults is an array split into four regions:
1611 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1612 * in this precise order.
1613 *
1614 * faults_memory: Exponential decaying average of faults on a per-node
1615 * basis. Scheduling placement decisions are made based on these
1616 * counts. The values remain static for the duration of a PTE scan.
1617 * faults_cpu: Track the nodes the process was running on when a NUMA
1618 * hinting fault was incurred.
1619 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1620 * during the current scan window. When the scan completes, the counts
1621 * in faults_memory and faults_cpu decay and these values are copied.
1622 */
1623 unsigned long *numa_faults;
1624 unsigned long total_numa_faults;
1625
1626 /*
1627 * numa_faults_locality tracks if faults recorded during the last
1628 * scan window were remote/local. The task scan period is adapted
1629 * based on the locality of the faults with different weights
1630 * depending on whether they were shared or private faults
1631 */
1632 unsigned long numa_faults_locality[2];
1633
1634 unsigned long numa_pages_migrated;
1635#endif /* CONFIG_NUMA_BALANCING */
1636
1637 struct rcu_head rcu;
1638
1639 /*
1640 * cache last used pipe for splice
1641 */
1642 struct pipe_inode_info *splice_pipe;
1643
1644 struct page_frag task_frag;
1645
1646#ifdef CONFIG_TASK_DELAY_ACCT
1647 struct task_delay_info *delays;
1648#endif
1649#ifdef CONFIG_FAULT_INJECTION
1650 int make_it_fail;
1651#endif
1652 /*
1653 * when (nr_dirtied >= nr_dirtied_pause), it's time to call
1654 * balance_dirty_pages() for some dirty throttling pause
1655 */
1656 int nr_dirtied;
1657 int nr_dirtied_pause;
1658 unsigned long dirty_paused_when; /* start of a write-and-pause period */
1659
1660#ifdef CONFIG_LATENCYTOP
1661 int latency_record_count;
1662 struct latency_record latency_record[LT_SAVECOUNT];
1663#endif
1664 /*
1665 * time slack values; these are used to round up poll() and
1666 * select() etc timeout values. These are in nanoseconds.
1667 */
1668 unsigned long timer_slack_ns;
1669 unsigned long default_timer_slack_ns;
1670
1671#ifdef CONFIG_KASAN
1672 unsigned int kasan_depth;
1673#endif
1674#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1675 /* Index of current stored address in ret_stack */
1676 int curr_ret_stack;
1677 /* Stack of return addresses for return function tracing */
1678 struct ftrace_ret_stack *ret_stack;
1679 /* time stamp for last schedule */
1680 unsigned long long ftrace_timestamp;
1681 /*
1682 * Number of functions that haven't been traced
1683 * because of depth overrun.
1684 */
1685 atomic_t trace_overrun;
1686 /* Pause for the tracing */
1687 atomic_t tracing_graph_pause;
1688#endif
1689#ifdef CONFIG_TRACING
1690 /* state flags for use by tracers */
1691 unsigned long trace;
1692 /* bitmask and counter of trace recursion */
1693 unsigned long trace_recursion;
1694#endif /* CONFIG_TRACING */
1695#ifdef CONFIG_MEMCG
1696 struct memcg_oom_info {
1697 struct mem_cgroup *memcg;
1698 gfp_t gfp_mask;
1699 int order;
1700 unsigned int may_oom:1;
1701 } memcg_oom;
1702#endif
1703#ifdef CONFIG_UPROBES
1704 struct uprobe_task *utask;
1705#endif
1706#if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1707 unsigned int sequential_io;
1708 unsigned int sequential_io_avg;
1709#endif
1710#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1711 unsigned long task_state_change;
1712#endif
1713};
1714
1715/* Future-safe accessor for struct task_struct's cpus_allowed. */
1716#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1717
1718#define TNF_MIGRATED 0x01
1719#define TNF_NO_GROUP 0x02
1720#define TNF_SHARED 0x04
1721#define TNF_FAULT_LOCAL 0x08
1722
1723#ifdef CONFIG_NUMA_BALANCING
1724extern void task_numa_fault(int last_node, int node, int pages, int flags);
1725extern pid_t task_numa_group_id(struct task_struct *p);
1726extern void set_numabalancing_state(bool enabled);
1727extern void task_numa_free(struct task_struct *p);
1728extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page,
1729 int src_nid, int dst_cpu);
1730#else
1731static inline void task_numa_fault(int last_node, int node, int pages,
1732 int flags)
1733{
1734}
1735static inline pid_t task_numa_group_id(struct task_struct *p)
1736{
1737 return 0;
1738}
1739static inline void set_numabalancing_state(bool enabled)
1740{
1741}
1742static inline void task_numa_free(struct task_struct *p)
1743{
1744}
1745static inline bool should_numa_migrate_memory(struct task_struct *p,
1746 struct page *page, int src_nid, int dst_cpu)
1747{
1748 return true;
1749}
1750#endif
1751
1752static inline struct pid *task_pid(struct task_struct *task)
1753{
1754 return task->pids[PIDTYPE_PID].pid;
1755}
1756
1757static inline struct pid *task_tgid(struct task_struct *task)
1758{
1759 return task->group_leader->pids[PIDTYPE_PID].pid;
1760}
1761
1762/*
1763 * Without tasklist or rcu lock it is not safe to dereference
1764 * the result of task_pgrp/task_session even if task == current,
1765 * we can race with another thread doing sys_setsid/sys_setpgid.
1766 */
1767static inline struct pid *task_pgrp(struct task_struct *task)
1768{
1769 return task->group_leader->pids[PIDTYPE_PGID].pid;
1770}
1771
1772static inline struct pid *task_session(struct task_struct *task)
1773{
1774 return task->group_leader->pids[PIDTYPE_SID].pid;
1775}
1776
1777struct pid_namespace;
1778
1779/*
1780 * the helpers to get the task's different pids as they are seen
1781 * from various namespaces
1782 *
1783 * task_xid_nr() : global id, i.e. the id seen from the init namespace;
1784 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of
1785 * current.
1786 * task_xid_nr_ns() : id seen from the ns specified;
1787 *
1788 * set_task_vxid() : assigns a virtual id to a task;
1789 *
1790 * see also pid_nr() etc in include/linux/pid.h
1791 */
1792pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1793 struct pid_namespace *ns);
1794
1795static inline pid_t task_pid_nr(struct task_struct *tsk)
1796{
1797 return tsk->pid;
1798}
1799
1800static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1801 struct pid_namespace *ns)
1802{
1803 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1804}
1805
1806static inline pid_t task_pid_vnr(struct task_struct *tsk)
1807{
1808 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1809}
1810
1811
1812static inline pid_t task_tgid_nr(struct task_struct *tsk)
1813{
1814 return tsk->tgid;
1815}
1816
1817pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1818
1819static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1820{
1821 return pid_vnr(task_tgid(tsk));
1822}
1823
1824
1825static inline int pid_alive(const struct task_struct *p);
1826static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1827{
1828 pid_t pid = 0;
1829
1830 rcu_read_lock();
1831 if (pid_alive(tsk))
1832 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1833 rcu_read_unlock();
1834
1835 return pid;
1836}
1837
1838static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1839{
1840 return task_ppid_nr_ns(tsk, &init_pid_ns);
1841}
1842
1843static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1844 struct pid_namespace *ns)
1845{
1846 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1847}
1848
1849static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1850{
1851 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1852}
1853
1854
1855static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1856 struct pid_namespace *ns)
1857{
1858 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1859}
1860
1861static inline pid_t task_session_vnr(struct task_struct *tsk)
1862{
1863 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1864}
1865
1866/* obsolete, do not use */
1867static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1868{
1869 return task_pgrp_nr_ns(tsk, &init_pid_ns);
1870}
1871
1872/**
1873 * pid_alive - check that a task structure is not stale
1874 * @p: Task structure to be checked.
1875 *
1876 * Test if a process is not yet dead (at most zombie state)
1877 * If pid_alive fails, then pointers within the task structure
1878 * can be stale and must not be dereferenced.
1879 *
1880 * Return: 1 if the process is alive. 0 otherwise.
1881 */
1882static inline int pid_alive(const struct task_struct *p)
1883{
1884 return p->pids[PIDTYPE_PID].pid != NULL;
1885}
1886
1887/**
1888 * is_global_init - check if a task structure is init
1889 * @tsk: Task structure to be checked.
1890 *
1891 * Check if a task structure is the first user space task the kernel created.
1892 *
1893 * Return: 1 if the task structure is init. 0 otherwise.
1894 */
1895static inline int is_global_init(struct task_struct *tsk)
1896{
1897 return tsk->pid == 1;
1898}
1899
1900extern struct pid *cad_pid;
1901
1902extern void free_task(struct task_struct *tsk);
1903#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1904
1905extern void __put_task_struct(struct task_struct *t);
1906
1907static inline void put_task_struct(struct task_struct *t)
1908{
1909 if (atomic_dec_and_test(&t->usage))
1910 __put_task_struct(t);
1911}
1912
1913#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1914extern void task_cputime(struct task_struct *t,
1915 cputime_t *utime, cputime_t *stime);
1916extern void task_cputime_scaled(struct task_struct *t,
1917 cputime_t *utimescaled, cputime_t *stimescaled);
1918extern cputime_t task_gtime(struct task_struct *t);
1919#else
1920static inline void task_cputime(struct task_struct *t,
1921 cputime_t *utime, cputime_t *stime)
1922{
1923 if (utime)
1924 *utime = t->utime;
1925 if (stime)
1926 *stime = t->stime;
1927}
1928
1929static inline void task_cputime_scaled(struct task_struct *t,
1930 cputime_t *utimescaled,
1931 cputime_t *stimescaled)
1932{
1933 if (utimescaled)
1934 *utimescaled = t->utimescaled;
1935 if (stimescaled)
1936 *stimescaled = t->stimescaled;
1937}
1938
1939static inline cputime_t task_gtime(struct task_struct *t)
1940{
1941 return t->gtime;
1942}
1943#endif
1944extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
1945extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
1946
1947/*
1948 * Per process flags
1949 */
1950#define PF_EXITING 0x00000004 /* getting shut down */
1951#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */
1952#define PF_VCPU 0x00000010 /* I'm a virtual CPU */
1953#define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */
1954#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
1955#define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */
1956#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
1957#define PF_DUMPCORE 0x00000200 /* dumped core */
1958#define PF_SIGNALED 0x00000400 /* killed by a signal */
1959#define PF_MEMALLOC 0x00000800 /* Allocating memory */
1960#define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */
1961#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
1962#define PF_USED_ASYNC 0x00004000 /* used async_schedule*(), used by module init */
1963#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
1964#define PF_FROZEN 0x00010000 /* frozen for system suspend */
1965#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
1966#define PF_KSWAPD 0x00040000 /* I am kswapd */
1967#define PF_MEMALLOC_NOIO 0x00080000 /* Allocating memory without IO involved */
1968#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
1969#define PF_KTHREAD 0x00200000 /* I am a kernel thread */
1970#define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */
1971#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1972#define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */
1973#define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
1974#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
1975#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */
1976#define PF_SUSPEND_TASK 0x80000000 /* this thread called freeze_processes and should not be frozen */
1977
1978/*
1979 * Only the _current_ task can read/write to tsk->flags, but other
1980 * tasks can access tsk->flags in readonly mode for example
1981 * with tsk_used_math (like during threaded core dumping).
1982 * There is however an exception to this rule during ptrace
1983 * or during fork: the ptracer task is allowed to write to the
1984 * child->flags of its traced child (same goes for fork, the parent
1985 * can write to the child->flags), because we're guaranteed the
1986 * child is not running and in turn not changing child->flags
1987 * at the same time the parent does it.
1988 */
1989#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1990#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1991#define clear_used_math() clear_stopped_child_used_math(current)
1992#define set_used_math() set_stopped_child_used_math(current)
1993#define conditional_stopped_child_used_math(condition, child) \
1994 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1995#define conditional_used_math(condition) \
1996 conditional_stopped_child_used_math(condition, current)
1997#define copy_to_stopped_child_used_math(child) \
1998 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1999/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
2000#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
2001#define used_math() tsk_used_math(current)
2002
2003/* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags
2004 * __GFP_FS is also cleared as it implies __GFP_IO.
2005 */
2006static inline gfp_t memalloc_noio_flags(gfp_t flags)
2007{
2008 if (unlikely(current->flags & PF_MEMALLOC_NOIO))
2009 flags &= ~(__GFP_IO | __GFP_FS);
2010 return flags;
2011}
2012
2013static inline unsigned int memalloc_noio_save(void)
2014{
2015 unsigned int flags = current->flags & PF_MEMALLOC_NOIO;
2016 current->flags |= PF_MEMALLOC_NOIO;
2017 return flags;
2018}
2019
2020static inline void memalloc_noio_restore(unsigned int flags)
2021{
2022 current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags;
2023}
2024
2025/* Per-process atomic flags. */
2026#define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */
2027#define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */
2028#define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */
2029
2030
2031#define TASK_PFA_TEST(name, func) \
2032 static inline bool task_##func(struct task_struct *p) \
2033 { return test_bit(PFA_##name, &p->atomic_flags); }
2034#define TASK_PFA_SET(name, func) \
2035 static inline void task_set_##func(struct task_struct *p) \
2036 { set_bit(PFA_##name, &p->atomic_flags); }
2037#define TASK_PFA_CLEAR(name, func) \
2038 static inline void task_clear_##func(struct task_struct *p) \
2039 { clear_bit(PFA_##name, &p->atomic_flags); }
2040
2041TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
2042TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
2043
2044TASK_PFA_TEST(SPREAD_PAGE, spread_page)
2045TASK_PFA_SET(SPREAD_PAGE, spread_page)
2046TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
2047
2048TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
2049TASK_PFA_SET(SPREAD_SLAB, spread_slab)
2050TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
2051
2052/*
2053 * task->jobctl flags
2054 */
2055#define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */
2056
2057#define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */
2058#define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */
2059#define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */
2060#define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */
2061#define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */
2062#define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */
2063#define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */
2064
2065#define JOBCTL_STOP_DEQUEUED (1 << JOBCTL_STOP_DEQUEUED_BIT)
2066#define JOBCTL_STOP_PENDING (1 << JOBCTL_STOP_PENDING_BIT)
2067#define JOBCTL_STOP_CONSUME (1 << JOBCTL_STOP_CONSUME_BIT)
2068#define JOBCTL_TRAP_STOP (1 << JOBCTL_TRAP_STOP_BIT)
2069#define JOBCTL_TRAP_NOTIFY (1 << JOBCTL_TRAP_NOTIFY_BIT)
2070#define JOBCTL_TRAPPING (1 << JOBCTL_TRAPPING_BIT)
2071#define JOBCTL_LISTENING (1 << JOBCTL_LISTENING_BIT)
2072
2073#define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY)
2074#define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK)
2075
2076extern bool task_set_jobctl_pending(struct task_struct *task,
2077 unsigned int mask);
2078extern void task_clear_jobctl_trapping(struct task_struct *task);
2079extern void task_clear_jobctl_pending(struct task_struct *task,
2080 unsigned int mask);
2081
2082static inline void rcu_copy_process(struct task_struct *p)
2083{
2084#ifdef CONFIG_PREEMPT_RCU
2085 p->rcu_read_lock_nesting = 0;
2086 p->rcu_read_unlock_special.s = 0;
2087 p->rcu_blocked_node = NULL;
2088 INIT_LIST_HEAD(&p->rcu_node_entry);
2089#endif /* #ifdef CONFIG_PREEMPT_RCU */
2090#ifdef CONFIG_TASKS_RCU
2091 p->rcu_tasks_holdout = false;
2092 INIT_LIST_HEAD(&p->rcu_tasks_holdout_list);
2093 p->rcu_tasks_idle_cpu = -1;
2094#endif /* #ifdef CONFIG_TASKS_RCU */
2095}
2096
2097static inline void tsk_restore_flags(struct task_struct *task,
2098 unsigned long orig_flags, unsigned long flags)
2099{
2100 task->flags &= ~flags;
2101 task->flags |= orig_flags & flags;
2102}
2103
2104extern int cpuset_cpumask_can_shrink(const struct cpumask *cur,
2105 const struct cpumask *trial);
2106extern int task_can_attach(struct task_struct *p,
2107 const struct cpumask *cs_cpus_allowed);
2108#ifdef CONFIG_SMP
2109extern void do_set_cpus_allowed(struct task_struct *p,
2110 const struct cpumask *new_mask);
2111
2112extern int set_cpus_allowed_ptr(struct task_struct *p,
2113 const struct cpumask *new_mask);
2114#else
2115static inline void do_set_cpus_allowed(struct task_struct *p,
2116 const struct cpumask *new_mask)
2117{
2118}
2119static inline int set_cpus_allowed_ptr(struct task_struct *p,
2120 const struct cpumask *new_mask)
2121{
2122 if (!cpumask_test_cpu(0, new_mask))
2123 return -EINVAL;
2124 return 0;
2125}
2126#endif
2127
2128#ifdef CONFIG_NO_HZ_COMMON
2129void calc_load_enter_idle(void);
2130void calc_load_exit_idle(void);
2131#else
2132static inline void calc_load_enter_idle(void) { }
2133static inline void calc_load_exit_idle(void) { }
2134#endif /* CONFIG_NO_HZ_COMMON */
2135
2136#ifndef CONFIG_CPUMASK_OFFSTACK
2137static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
2138{
2139 return set_cpus_allowed_ptr(p, &new_mask);
2140}
2141#endif
2142
2143/*
2144 * Do not use outside of architecture code which knows its limitations.
2145 *
2146 * sched_clock() has no promise of monotonicity or bounded drift between
2147 * CPUs, use (which you should not) requires disabling IRQs.
2148 *
2149 * Please use one of the three interfaces below.
2150 */
2151extern unsigned long long notrace sched_clock(void);
2152/*
2153 * See the comment in kernel/sched/clock.c
2154 */
2155extern u64 cpu_clock(int cpu);
2156extern u64 local_clock(void);
2157extern u64 running_clock(void);
2158extern u64 sched_clock_cpu(int cpu);
2159
2160
2161extern void sched_clock_init(void);
2162
2163#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
2164static inline void sched_clock_tick(void)
2165{
2166}
2167
2168static inline void sched_clock_idle_sleep_event(void)
2169{
2170}
2171
2172static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
2173{
2174}
2175#else
2176/*
2177 * Architectures can set this to 1 if they have specified
2178 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
2179 * but then during bootup it turns out that sched_clock()
2180 * is reliable after all:
2181 */
2182extern int sched_clock_stable(void);
2183extern void set_sched_clock_stable(void);
2184extern void clear_sched_clock_stable(void);
2185
2186extern void sched_clock_tick(void);
2187extern void sched_clock_idle_sleep_event(void);
2188extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2189#endif
2190
2191#ifdef CONFIG_IRQ_TIME_ACCOUNTING
2192/*
2193 * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
2194 * The reason for this explicit opt-in is not to have perf penalty with
2195 * slow sched_clocks.
2196 */
2197extern void enable_sched_clock_irqtime(void);
2198extern void disable_sched_clock_irqtime(void);
2199#else
2200static inline void enable_sched_clock_irqtime(void) {}
2201static inline void disable_sched_clock_irqtime(void) {}
2202#endif
2203
2204extern unsigned long long
2205task_sched_runtime(struct task_struct *task);
2206
2207/* sched_exec is called by processes performing an exec */
2208#ifdef CONFIG_SMP
2209extern void sched_exec(void);
2210#else
2211#define sched_exec() {}
2212#endif
2213
2214extern void sched_clock_idle_sleep_event(void);
2215extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2216
2217#ifdef CONFIG_HOTPLUG_CPU
2218extern void idle_task_exit(void);
2219#else
2220static inline void idle_task_exit(void) {}
2221#endif
2222
2223#if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
2224extern void wake_up_nohz_cpu(int cpu);
2225#else
2226static inline void wake_up_nohz_cpu(int cpu) { }
2227#endif
2228
2229#ifdef CONFIG_NO_HZ_FULL
2230extern bool sched_can_stop_tick(void);
2231extern u64 scheduler_tick_max_deferment(void);
2232#else
2233static inline bool sched_can_stop_tick(void) { return false; }
2234#endif
2235
2236#ifdef CONFIG_SCHED_AUTOGROUP
2237extern void sched_autogroup_create_attach(struct task_struct *p);
2238extern void sched_autogroup_detach(struct task_struct *p);
2239extern void sched_autogroup_fork(struct signal_struct *sig);
2240extern void sched_autogroup_exit(struct signal_struct *sig);
2241#ifdef CONFIG_PROC_FS
2242extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
2243extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice);
2244#endif
2245#else
2246static inline void sched_autogroup_create_attach(struct task_struct *p) { }
2247static inline void sched_autogroup_detach(struct task_struct *p) { }
2248static inline void sched_autogroup_fork(struct signal_struct *sig) { }
2249static inline void sched_autogroup_exit(struct signal_struct *sig) { }
2250#endif
2251
2252extern int yield_to(struct task_struct *p, bool preempt);
2253extern void set_user_nice(struct task_struct *p, long nice);
2254extern int task_prio(const struct task_struct *p);
2255/**
2256 * task_nice - return the nice value of a given task.
2257 * @p: the task in question.
2258 *
2259 * Return: The nice value [ -20 ... 0 ... 19 ].
2260 */
2261static inline int task_nice(const struct task_struct *p)
2262{
2263 return PRIO_TO_NICE((p)->static_prio);
2264}
2265extern int can_nice(const struct task_struct *p, const int nice);
2266extern int task_curr(const struct task_struct *p);
2267extern int idle_cpu(int cpu);
2268extern int sched_setscheduler(struct task_struct *, int,
2269 const struct sched_param *);
2270extern int sched_setscheduler_nocheck(struct task_struct *, int,
2271 const struct sched_param *);
2272extern int sched_setattr(struct task_struct *,
2273 const struct sched_attr *);
2274extern struct task_struct *idle_task(int cpu);
2275/**
2276 * is_idle_task - is the specified task an idle task?
2277 * @p: the task in question.
2278 *
2279 * Return: 1 if @p is an idle task. 0 otherwise.
2280 */
2281static inline bool is_idle_task(const struct task_struct *p)
2282{
2283 return p->pid == 0;
2284}
2285extern struct task_struct *curr_task(int cpu);
2286extern void set_curr_task(int cpu, struct task_struct *p);
2287
2288void yield(void);
2289
2290/*
2291 * The default (Linux) execution domain.
2292 */
2293extern struct exec_domain default_exec_domain;
2294
2295union thread_union {
2296 struct thread_info thread_info;
2297 unsigned long stack[THREAD_SIZE/sizeof(long)];
2298};
2299
2300#ifndef __HAVE_ARCH_KSTACK_END
2301static inline int kstack_end(void *addr)
2302{
2303 /* Reliable end of stack detection:
2304 * Some APM bios versions misalign the stack
2305 */
2306 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
2307}
2308#endif
2309
2310extern union thread_union init_thread_union;
2311extern struct task_struct init_task;
2312
2313extern struct mm_struct init_mm;
2314
2315extern struct pid_namespace init_pid_ns;
2316
2317/*
2318 * find a task by one of its numerical ids
2319 *
2320 * find_task_by_pid_ns():
2321 * finds a task by its pid in the specified namespace
2322 * find_task_by_vpid():
2323 * finds a task by its virtual pid
2324 *
2325 * see also find_vpid() etc in include/linux/pid.h
2326 */
2327
2328extern struct task_struct *find_task_by_vpid(pid_t nr);
2329extern struct task_struct *find_task_by_pid_ns(pid_t nr,
2330 struct pid_namespace *ns);
2331
2332/* per-UID process charging. */
2333extern struct user_struct * alloc_uid(kuid_t);
2334static inline struct user_struct *get_uid(struct user_struct *u)
2335{
2336 atomic_inc(&u->__count);
2337 return u;
2338}
2339extern void free_uid(struct user_struct *);
2340
2341#include <asm/current.h>
2342
2343extern void xtime_update(unsigned long ticks);
2344
2345extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2346extern int wake_up_process(struct task_struct *tsk);
2347extern void wake_up_new_task(struct task_struct *tsk);
2348#ifdef CONFIG_SMP
2349 extern void kick_process(struct task_struct *tsk);
2350#else
2351 static inline void kick_process(struct task_struct *tsk) { }
2352#endif
2353extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
2354extern void sched_dead(struct task_struct *p);
2355
2356extern void proc_caches_init(void);
2357extern void flush_signals(struct task_struct *);
2358extern void __flush_signals(struct task_struct *);
2359extern void ignore_signals(struct task_struct *);
2360extern void flush_signal_handlers(struct task_struct *, int force_default);
2361extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2362
2363static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
2364{
2365 unsigned long flags;
2366 int ret;
2367
2368 spin_lock_irqsave(&tsk->sighand->siglock, flags);
2369 ret = dequeue_signal(tsk, mask, info);
2370 spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
2371
2372 return ret;
2373}
2374
2375extern void block_all_signals(int (*notifier)(void *priv), void *priv,
2376 sigset_t *mask);
2377extern void unblock_all_signals(void);
2378extern void release_task(struct task_struct * p);
2379extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2380extern int force_sigsegv(int, struct task_struct *);
2381extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2382extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2383extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2384extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *,
2385 const struct cred *, u32);
2386extern int kill_pgrp(struct pid *pid, int sig, int priv);
2387extern int kill_pid(struct pid *pid, int sig, int priv);
2388extern int kill_proc_info(int, struct siginfo *, pid_t);
2389extern __must_check bool do_notify_parent(struct task_struct *, int);
2390extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2391extern void force_sig(int, struct task_struct *);
2392extern int send_sig(int, struct task_struct *, int);
2393extern int zap_other_threads(struct task_struct *p);
2394extern struct sigqueue *sigqueue_alloc(void);
2395extern void sigqueue_free(struct sigqueue *);
2396extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group);
2397extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2398
2399static inline void restore_saved_sigmask(void)
2400{
2401 if (test_and_clear_restore_sigmask())
2402 __set_current_blocked(¤t->saved_sigmask);
2403}
2404
2405static inline sigset_t *sigmask_to_save(void)
2406{
2407 sigset_t *res = ¤t->blocked;
2408 if (unlikely(test_restore_sigmask()))
2409 res = ¤t->saved_sigmask;
2410 return res;
2411}
2412
2413static inline int kill_cad_pid(int sig, int priv)
2414{
2415 return kill_pid(cad_pid, sig, priv);
2416}
2417
2418/* These can be the second arg to send_sig_info/send_group_sig_info. */
2419#define SEND_SIG_NOINFO ((struct siginfo *) 0)
2420#define SEND_SIG_PRIV ((struct siginfo *) 1)
2421#define SEND_SIG_FORCED ((struct siginfo *) 2)
2422
2423/*
2424 * True if we are on the alternate signal stack.
2425 */
2426static inline int on_sig_stack(unsigned long sp)
2427{
2428#ifdef CONFIG_STACK_GROWSUP
2429 return sp >= current->sas_ss_sp &&
2430 sp - current->sas_ss_sp < current->sas_ss_size;
2431#else
2432 return sp > current->sas_ss_sp &&
2433 sp - current->sas_ss_sp <= current->sas_ss_size;
2434#endif
2435}
2436
2437static inline int sas_ss_flags(unsigned long sp)
2438{
2439 if (!current->sas_ss_size)
2440 return SS_DISABLE;
2441
2442 return on_sig_stack(sp) ? SS_ONSTACK : 0;
2443}
2444
2445static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig)
2446{
2447 if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp))
2448#ifdef CONFIG_STACK_GROWSUP
2449 return current->sas_ss_sp;
2450#else
2451 return current->sas_ss_sp + current->sas_ss_size;
2452#endif
2453 return sp;
2454}
2455
2456/*
2457 * Routines for handling mm_structs
2458 */
2459extern struct mm_struct * mm_alloc(void);
2460
2461/* mmdrop drops the mm and the page tables */
2462extern void __mmdrop(struct mm_struct *);
2463static inline void mmdrop(struct mm_struct * mm)
2464{
2465 if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2466 __mmdrop(mm);
2467}
2468
2469/* mmput gets rid of the mappings and all user-space */
2470extern void mmput(struct mm_struct *);
2471/* Grab a reference to a task's mm, if it is not already going away */
2472extern struct mm_struct *get_task_mm(struct task_struct *task);
2473/*
2474 * Grab a reference to a task's mm, if it is not already going away
2475 * and ptrace_may_access with the mode parameter passed to it
2476 * succeeds.
2477 */
2478extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode);
2479/* Remove the current tasks stale references to the old mm_struct */
2480extern void mm_release(struct task_struct *, struct mm_struct *);
2481
2482extern int copy_thread(unsigned long, unsigned long, unsigned long,
2483 struct task_struct *);
2484extern void flush_thread(void);
2485extern void exit_thread(void);
2486
2487extern void exit_files(struct task_struct *);
2488extern void __cleanup_sighand(struct sighand_struct *);
2489
2490extern void exit_itimers(struct signal_struct *);
2491extern void flush_itimer_signals(void);
2492
2493extern void do_group_exit(int);
2494
2495extern int do_execve(struct filename *,
2496 const char __user * const __user *,
2497 const char __user * const __user *);
2498extern int do_execveat(int, struct filename *,
2499 const char __user * const __user *,
2500 const char __user * const __user *,
2501 int);
2502extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
2503struct task_struct *fork_idle(int);
2504extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
2505
2506extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
2507static inline void set_task_comm(struct task_struct *tsk, const char *from)
2508{
2509 __set_task_comm(tsk, from, false);
2510}
2511extern char *get_task_comm(char *to, struct task_struct *tsk);
2512
2513#ifdef CONFIG_SMP
2514void scheduler_ipi(void);
2515extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2516#else
2517static inline void scheduler_ipi(void) { }
2518static inline unsigned long wait_task_inactive(struct task_struct *p,
2519 long match_state)
2520{
2521 return 1;
2522}
2523#endif
2524
2525#define next_task(p) \
2526 list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2527
2528#define for_each_process(p) \
2529 for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2530
2531extern bool current_is_single_threaded(void);
2532
2533/*
2534 * Careful: do_each_thread/while_each_thread is a double loop so
2535 * 'break' will not work as expected - use goto instead.
2536 */
2537#define do_each_thread(g, t) \
2538 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2539
2540#define while_each_thread(g, t) \
2541 while ((t = next_thread(t)) != g)
2542
2543#define __for_each_thread(signal, t) \
2544 list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node)
2545
2546#define for_each_thread(p, t) \
2547 __for_each_thread((p)->signal, t)
2548
2549/* Careful: this is a double loop, 'break' won't work as expected. */
2550#define for_each_process_thread(p, t) \
2551 for_each_process(p) for_each_thread(p, t)
2552
2553static inline int get_nr_threads(struct task_struct *tsk)
2554{
2555 return tsk->signal->nr_threads;
2556}
2557
2558static inline bool thread_group_leader(struct task_struct *p)
2559{
2560 return p->exit_signal >= 0;
2561}
2562
2563/* Do to the insanities of de_thread it is possible for a process
2564 * to have the pid of the thread group leader without actually being
2565 * the thread group leader. For iteration through the pids in proc
2566 * all we care about is that we have a task with the appropriate
2567 * pid, we don't actually care if we have the right task.
2568 */
2569static inline bool has_group_leader_pid(struct task_struct *p)
2570{
2571 return task_pid(p) == p->signal->leader_pid;
2572}
2573
2574static inline
2575bool same_thread_group(struct task_struct *p1, struct task_struct *p2)
2576{
2577 return p1->signal == p2->signal;
2578}
2579
2580static inline struct task_struct *next_thread(const struct task_struct *p)
2581{
2582 return list_entry_rcu(p->thread_group.next,
2583 struct task_struct, thread_group);
2584}
2585
2586static inline int thread_group_empty(struct task_struct *p)
2587{
2588 return list_empty(&p->thread_group);
2589}
2590
2591#define delay_group_leader(p) \
2592 (thread_group_leader(p) && !thread_group_empty(p))
2593
2594/*
2595 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2596 * subscriptions and synchronises with wait4(). Also used in procfs. Also
2597 * pins the final release of task.io_context. Also protects ->cpuset and
2598 * ->cgroup.subsys[]. And ->vfork_done.
2599 *
2600 * Nests both inside and outside of read_lock(&tasklist_lock).
2601 * It must not be nested with write_lock_irq(&tasklist_lock),
2602 * neither inside nor outside.
2603 */
2604static inline void task_lock(struct task_struct *p)
2605{
2606 spin_lock(&p->alloc_lock);
2607}
2608
2609static inline void task_unlock(struct task_struct *p)
2610{
2611 spin_unlock(&p->alloc_lock);
2612}
2613
2614extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2615 unsigned long *flags);
2616
2617static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2618 unsigned long *flags)
2619{
2620 struct sighand_struct *ret;
2621
2622 ret = __lock_task_sighand(tsk, flags);
2623 (void)__cond_lock(&tsk->sighand->siglock, ret);
2624 return ret;
2625}
2626
2627static inline void unlock_task_sighand(struct task_struct *tsk,
2628 unsigned long *flags)
2629{
2630 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2631}
2632
2633#ifdef CONFIG_CGROUPS
2634static inline void threadgroup_change_begin(struct task_struct *tsk)
2635{
2636 down_read(&tsk->signal->group_rwsem);
2637}
2638static inline void threadgroup_change_end(struct task_struct *tsk)
2639{
2640 up_read(&tsk->signal->group_rwsem);
2641}
2642
2643/**
2644 * threadgroup_lock - lock threadgroup
2645 * @tsk: member task of the threadgroup to lock
2646 *
2647 * Lock the threadgroup @tsk belongs to. No new task is allowed to enter
2648 * and member tasks aren't allowed to exit (as indicated by PF_EXITING) or
2649 * change ->group_leader/pid. This is useful for cases where the threadgroup
2650 * needs to stay stable across blockable operations.
2651 *
2652 * fork and exit paths explicitly call threadgroup_change_{begin|end}() for
2653 * synchronization. While held, no new task will be added to threadgroup
2654 * and no existing live task will have its PF_EXITING set.
2655 *
2656 * de_thread() does threadgroup_change_{begin|end}() when a non-leader
2657 * sub-thread becomes a new leader.
2658 */
2659static inline void threadgroup_lock(struct task_struct *tsk)
2660{
2661 down_write(&tsk->signal->group_rwsem);
2662}
2663
2664/**
2665 * threadgroup_unlock - unlock threadgroup
2666 * @tsk: member task of the threadgroup to unlock
2667 *
2668 * Reverse threadgroup_lock().
2669 */
2670static inline void threadgroup_unlock(struct task_struct *tsk)
2671{
2672 up_write(&tsk->signal->group_rwsem);
2673}
2674#else
2675static inline void threadgroup_change_begin(struct task_struct *tsk) {}
2676static inline void threadgroup_change_end(struct task_struct *tsk) {}
2677static inline void threadgroup_lock(struct task_struct *tsk) {}
2678static inline void threadgroup_unlock(struct task_struct *tsk) {}
2679#endif
2680
2681#ifndef __HAVE_THREAD_FUNCTIONS
2682
2683#define task_thread_info(task) ((struct thread_info *)(task)->stack)
2684#define task_stack_page(task) ((task)->stack)
2685
2686static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2687{
2688 *task_thread_info(p) = *task_thread_info(org);
2689 task_thread_info(p)->task = p;
2690}
2691
2692/*
2693 * Return the address of the last usable long on the stack.
2694 *
2695 * When the stack grows down, this is just above the thread
2696 * info struct. Going any lower will corrupt the threadinfo.
2697 *
2698 * When the stack grows up, this is the highest address.
2699 * Beyond that position, we corrupt data on the next page.
2700 */
2701static inline unsigned long *end_of_stack(struct task_struct *p)
2702{
2703#ifdef CONFIG_STACK_GROWSUP
2704 return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1;
2705#else
2706 return (unsigned long *)(task_thread_info(p) + 1);
2707#endif
2708}
2709
2710#endif
2711#define task_stack_end_corrupted(task) \
2712 (*(end_of_stack(task)) != STACK_END_MAGIC)
2713
2714static inline int object_is_on_stack(void *obj)
2715{
2716 void *stack = task_stack_page(current);
2717
2718 return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2719}
2720
2721extern void thread_info_cache_init(void);
2722
2723#ifdef CONFIG_DEBUG_STACK_USAGE
2724static inline unsigned long stack_not_used(struct task_struct *p)
2725{
2726 unsigned long *n = end_of_stack(p);
2727
2728 do { /* Skip over canary */
2729 n++;
2730 } while (!*n);
2731
2732 return (unsigned long)n - (unsigned long)end_of_stack(p);
2733}
2734#endif
2735extern void set_task_stack_end_magic(struct task_struct *tsk);
2736
2737/* set thread flags in other task's structures
2738 * - see asm/thread_info.h for TIF_xxxx flags available
2739 */
2740static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2741{
2742 set_ti_thread_flag(task_thread_info(tsk), flag);
2743}
2744
2745static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2746{
2747 clear_ti_thread_flag(task_thread_info(tsk), flag);
2748}
2749
2750static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2751{
2752 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2753}
2754
2755static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2756{
2757 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2758}
2759
2760static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2761{
2762 return test_ti_thread_flag(task_thread_info(tsk), flag);
2763}
2764
2765static inline void set_tsk_need_resched(struct task_struct *tsk)
2766{
2767 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2768}
2769
2770static inline void clear_tsk_need_resched(struct task_struct *tsk)
2771{
2772 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2773}
2774
2775static inline int test_tsk_need_resched(struct task_struct *tsk)
2776{
2777 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2778}
2779
2780static inline int restart_syscall(void)
2781{
2782 set_tsk_thread_flag(current, TIF_SIGPENDING);
2783 return -ERESTARTNOINTR;
2784}
2785
2786static inline int signal_pending(struct task_struct *p)
2787{
2788 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2789}
2790
2791static inline int __fatal_signal_pending(struct task_struct *p)
2792{
2793 return unlikely(sigismember(&p->pending.signal, SIGKILL));
2794}
2795
2796static inline int fatal_signal_pending(struct task_struct *p)
2797{
2798 return signal_pending(p) && __fatal_signal_pending(p);
2799}
2800
2801static inline int signal_pending_state(long state, struct task_struct *p)
2802{
2803 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2804 return 0;
2805 if (!signal_pending(p))
2806 return 0;
2807
2808 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2809}
2810
2811/*
2812 * cond_resched() and cond_resched_lock(): latency reduction via
2813 * explicit rescheduling in places that are safe. The return
2814 * value indicates whether a reschedule was done in fact.
2815 * cond_resched_lock() will drop the spinlock before scheduling,
2816 * cond_resched_softirq() will enable bhs before scheduling.
2817 */
2818extern int _cond_resched(void);
2819
2820#define cond_resched() ({ \
2821 ___might_sleep(__FILE__, __LINE__, 0); \
2822 _cond_resched(); \
2823})
2824
2825extern int __cond_resched_lock(spinlock_t *lock);
2826
2827#ifdef CONFIG_PREEMPT_COUNT
2828#define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET
2829#else
2830#define PREEMPT_LOCK_OFFSET 0
2831#endif
2832
2833#define cond_resched_lock(lock) ({ \
2834 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
2835 __cond_resched_lock(lock); \
2836})
2837
2838extern int __cond_resched_softirq(void);
2839
2840#define cond_resched_softirq() ({ \
2841 ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \
2842 __cond_resched_softirq(); \
2843})
2844
2845static inline void cond_resched_rcu(void)
2846{
2847#if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
2848 rcu_read_unlock();
2849 cond_resched();
2850 rcu_read_lock();
2851#endif
2852}
2853
2854/*
2855 * Does a critical section need to be broken due to another
2856 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2857 * but a general need for low latency)
2858 */
2859static inline int spin_needbreak(spinlock_t *lock)
2860{
2861#ifdef CONFIG_PREEMPT
2862 return spin_is_contended(lock);
2863#else
2864 return 0;
2865#endif
2866}
2867
2868/*
2869 * Idle thread specific functions to determine the need_resched
2870 * polling state.
2871 */
2872#ifdef TIF_POLLING_NRFLAG
2873static inline int tsk_is_polling(struct task_struct *p)
2874{
2875 return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG);
2876}
2877
2878static inline void __current_set_polling(void)
2879{
2880 set_thread_flag(TIF_POLLING_NRFLAG);
2881}
2882
2883static inline bool __must_check current_set_polling_and_test(void)
2884{
2885 __current_set_polling();
2886
2887 /*
2888 * Polling state must be visible before we test NEED_RESCHED,
2889 * paired by resched_curr()
2890 */
2891 smp_mb__after_atomic();
2892
2893 return unlikely(tif_need_resched());
2894}
2895
2896static inline void __current_clr_polling(void)
2897{
2898 clear_thread_flag(TIF_POLLING_NRFLAG);
2899}
2900
2901static inline bool __must_check current_clr_polling_and_test(void)
2902{
2903 __current_clr_polling();
2904
2905 /*
2906 * Polling state must be visible before we test NEED_RESCHED,
2907 * paired by resched_curr()
2908 */
2909 smp_mb__after_atomic();
2910
2911 return unlikely(tif_need_resched());
2912}
2913
2914#else
2915static inline int tsk_is_polling(struct task_struct *p) { return 0; }
2916static inline void __current_set_polling(void) { }
2917static inline void __current_clr_polling(void) { }
2918
2919static inline bool __must_check current_set_polling_and_test(void)
2920{
2921 return unlikely(tif_need_resched());
2922}
2923static inline bool __must_check current_clr_polling_and_test(void)
2924{
2925 return unlikely(tif_need_resched());
2926}
2927#endif
2928
2929static inline void current_clr_polling(void)
2930{
2931 __current_clr_polling();
2932
2933 /*
2934 * Ensure we check TIF_NEED_RESCHED after we clear the polling bit.
2935 * Once the bit is cleared, we'll get IPIs with every new
2936 * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also
2937 * fold.
2938 */
2939 smp_mb(); /* paired with resched_curr() */
2940
2941 preempt_fold_need_resched();
2942}
2943
2944static __always_inline bool need_resched(void)
2945{
2946 return unlikely(tif_need_resched());
2947}
2948
2949/*
2950 * Thread group CPU time accounting.
2951 */
2952void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2953void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2954
2955static inline void thread_group_cputime_init(struct signal_struct *sig)
2956{
2957 raw_spin_lock_init(&sig->cputimer.lock);
2958}
2959
2960/*
2961 * Reevaluate whether the task has signals pending delivery.
2962 * Wake the task if so.
2963 * This is required every time the blocked sigset_t changes.
2964 * callers must hold sighand->siglock.
2965 */
2966extern void recalc_sigpending_and_wake(struct task_struct *t);
2967extern void recalc_sigpending(void);
2968
2969extern void signal_wake_up_state(struct task_struct *t, unsigned int state);
2970
2971static inline void signal_wake_up(struct task_struct *t, bool resume)
2972{
2973 signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
2974}
2975static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
2976{
2977 signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
2978}
2979
2980/*
2981 * Wrappers for p->thread_info->cpu access. No-op on UP.
2982 */
2983#ifdef CONFIG_SMP
2984
2985static inline unsigned int task_cpu(const struct task_struct *p)
2986{
2987 return task_thread_info(p)->cpu;
2988}
2989
2990static inline int task_node(const struct task_struct *p)
2991{
2992 return cpu_to_node(task_cpu(p));
2993}
2994
2995extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2996
2997#else
2998
2999static inline unsigned int task_cpu(const struct task_struct *p)
3000{
3001 return 0;
3002}
3003
3004static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
3005{
3006}
3007
3008#endif /* CONFIG_SMP */
3009
3010extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
3011extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
3012
3013#ifdef CONFIG_CGROUP_SCHED
3014extern struct task_group root_task_group;
3015#endif /* CONFIG_CGROUP_SCHED */
3016
3017extern int task_can_switch_user(struct user_struct *up,
3018 struct task_struct *tsk);
3019
3020#ifdef CONFIG_TASK_XACCT
3021static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3022{
3023 tsk->ioac.rchar += amt;
3024}
3025
3026static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3027{
3028 tsk->ioac.wchar += amt;
3029}
3030
3031static inline void inc_syscr(struct task_struct *tsk)
3032{
3033 tsk->ioac.syscr++;
3034}
3035
3036static inline void inc_syscw(struct task_struct *tsk)
3037{
3038 tsk->ioac.syscw++;
3039}
3040#else
3041static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3042{
3043}
3044
3045static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3046{
3047}
3048
3049static inline void inc_syscr(struct task_struct *tsk)
3050{
3051}
3052
3053static inline void inc_syscw(struct task_struct *tsk)
3054{
3055}
3056#endif
3057
3058#ifndef TASK_SIZE_OF
3059#define TASK_SIZE_OF(tsk) TASK_SIZE
3060#endif
3061
3062#ifdef CONFIG_MEMCG
3063extern void mm_update_next_owner(struct mm_struct *mm);
3064#else
3065static inline void mm_update_next_owner(struct mm_struct *mm)
3066{
3067}
3068#endif /* CONFIG_MEMCG */
3069
3070static inline unsigned long task_rlimit(const struct task_struct *tsk,
3071 unsigned int limit)
3072{
3073 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur);
3074}
3075
3076static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
3077 unsigned int limit)
3078{
3079 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max);
3080}
3081
3082static inline unsigned long rlimit(unsigned int limit)
3083{
3084 return task_rlimit(current, limit);
3085}
3086
3087static inline unsigned long rlimit_max(unsigned int limit)
3088{
3089 return task_rlimit_max(current, limit);
3090}
3091
3092#endif