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1#ifndef _LINUX_SCHED_H
2#define _LINUX_SCHED_H
3
4/*
5 * cloning flags:
6 */
7#define CSIGNAL 0x000000ff /* signal mask to be sent at exit */
8#define CLONE_VM 0x00000100 /* set if VM shared between processes */
9#define CLONE_FS 0x00000200 /* set if fs info shared between processes */
10#define CLONE_FILES 0x00000400 /* set if open files shared between processes */
11#define CLONE_SIGHAND 0x00000800 /* set if signal handlers and blocked signals shared */
12#define CLONE_PTRACE 0x00002000 /* set if we want to let tracing continue on the child too */
13#define CLONE_VFORK 0x00004000 /* set if the parent wants the child to wake it up on mm_release */
14#define CLONE_PARENT 0x00008000 /* set if we want to have the same parent as the cloner */
15#define CLONE_THREAD 0x00010000 /* Same thread group? */
16#define CLONE_NEWNS 0x00020000 /* New namespace group? */
17#define CLONE_SYSVSEM 0x00040000 /* share system V SEM_UNDO semantics */
18#define CLONE_SETTLS 0x00080000 /* create a new TLS for the child */
19#define CLONE_PARENT_SETTID 0x00100000 /* set the TID in the parent */
20#define CLONE_CHILD_CLEARTID 0x00200000 /* clear the TID in the child */
21#define CLONE_DETACHED 0x00400000 /* Unused, ignored */
22#define CLONE_UNTRACED 0x00800000 /* set if the tracing process can't force CLONE_PTRACE on this clone */
23#define CLONE_CHILD_SETTID 0x01000000 /* set the TID in the child */
24#define CLONE_STOPPED 0x02000000 /* Start in stopped state */
25#define CLONE_NEWUTS 0x04000000 /* New utsname group? */
26#define CLONE_NEWIPC 0x08000000 /* New ipcs */
27#define CLONE_NEWUSER 0x10000000 /* New user namespace */
28#define CLONE_NEWPID 0x20000000 /* New pid namespace */
29#define CLONE_NEWNET 0x40000000 /* New network namespace */
30#define CLONE_IO 0x80000000 /* Clone io context */
31
32/*
33 * Scheduling policies
34 */
35#define SCHED_NORMAL 0
36#define SCHED_FIFO 1
37#define SCHED_RR 2
38#define SCHED_BATCH 3
39/* SCHED_ISO: reserved but not implemented yet */
40#define SCHED_IDLE 5
41/* Can be ORed in to make sure the process is reverted back to SCHED_NORMAL on fork */
42#define SCHED_RESET_ON_FORK 0x40000000
43
44#ifdef __KERNEL__
45
46struct sched_param {
47 int sched_priority;
48};
49
50#include <asm/param.h> /* for HZ */
51
52#include <linux/capability.h>
53#include <linux/threads.h>
54#include <linux/kernel.h>
55#include <linux/types.h>
56#include <linux/timex.h>
57#include <linux/jiffies.h>
58#include <linux/rbtree.h>
59#include <linux/thread_info.h>
60#include <linux/cpumask.h>
61#include <linux/errno.h>
62#include <linux/nodemask.h>
63#include <linux/mm_types.h>
64
65#include <asm/system.h>
66#include <asm/page.h>
67#include <asm/ptrace.h>
68#include <asm/cputime.h>
69
70#include <linux/smp.h>
71#include <linux/sem.h>
72#include <linux/signal.h>
73#include <linux/path.h>
74#include <linux/compiler.h>
75#include <linux/completion.h>
76#include <linux/pid.h>
77#include <linux/percpu.h>
78#include <linux/topology.h>
79#include <linux/proportions.h>
80#include <linux/seccomp.h>
81#include <linux/rcupdate.h>
82#include <linux/rculist.h>
83#include <linux/rtmutex.h>
84
85#include <linux/time.h>
86#include <linux/param.h>
87#include <linux/resource.h>
88#include <linux/timer.h>
89#include <linux/hrtimer.h>
90#include <linux/task_io_accounting.h>
91#include <linux/kobject.h>
92#include <linux/latencytop.h>
93#include <linux/cred.h>
94
95#include <asm/processor.h>
96
97struct exec_domain;
98struct futex_pi_state;
99struct robust_list_head;
100struct bio_list;
101struct fs_struct;
102struct perf_event_context;
103
104/*
105 * List of flags we want to share for kernel threads,
106 * if only because they are not used by them anyway.
107 */
108#define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
109
110/*
111 * These are the constant used to fake the fixed-point load-average
112 * counting. Some notes:
113 * - 11 bit fractions expand to 22 bits by the multiplies: this gives
114 * a load-average precision of 10 bits integer + 11 bits fractional
115 * - if you want to count load-averages more often, you need more
116 * precision, or rounding will get you. With 2-second counting freq,
117 * the EXP_n values would be 1981, 2034 and 2043 if still using only
118 * 11 bit fractions.
119 */
120extern unsigned long avenrun[]; /* Load averages */
121extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
122
123#define FSHIFT 11 /* nr of bits of precision */
124#define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
125#define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */
126#define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
127#define EXP_5 2014 /* 1/exp(5sec/5min) */
128#define EXP_15 2037 /* 1/exp(5sec/15min) */
129
130#define CALC_LOAD(load,exp,n) \
131 load *= exp; \
132 load += n*(FIXED_1-exp); \
133 load >>= FSHIFT;
134
135extern unsigned long total_forks;
136extern int nr_threads;
137DECLARE_PER_CPU(unsigned long, process_counts);
138extern int nr_processes(void);
139extern unsigned long nr_running(void);
140extern unsigned long nr_uninterruptible(void);
141extern unsigned long nr_iowait(void);
142extern unsigned long nr_iowait_cpu(int cpu);
143extern unsigned long this_cpu_load(void);
144
145
146extern void calc_global_load(void);
147
148extern unsigned long get_parent_ip(unsigned long addr);
149
150struct seq_file;
151struct cfs_rq;
152struct task_group;
153#ifdef CONFIG_SCHED_DEBUG
154extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
155extern void proc_sched_set_task(struct task_struct *p);
156extern void
157print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
158#else
159static inline void
160proc_sched_show_task(struct task_struct *p, struct seq_file *m)
161{
162}
163static inline void proc_sched_set_task(struct task_struct *p)
164{
165}
166static inline void
167print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
168{
169}
170#endif
171
172/*
173 * Task state bitmask. NOTE! These bits are also
174 * encoded in fs/proc/array.c: get_task_state().
175 *
176 * We have two separate sets of flags: task->state
177 * is about runnability, while task->exit_state are
178 * about the task exiting. Confusing, but this way
179 * modifying one set can't modify the other one by
180 * mistake.
181 */
182#define TASK_RUNNING 0
183#define TASK_INTERRUPTIBLE 1
184#define TASK_UNINTERRUPTIBLE 2
185#define __TASK_STOPPED 4
186#define __TASK_TRACED 8
187/* in tsk->exit_state */
188#define EXIT_ZOMBIE 16
189#define EXIT_DEAD 32
190/* in tsk->state again */
191#define TASK_DEAD 64
192#define TASK_WAKEKILL 128
193#define TASK_WAKING 256
194#define TASK_STATE_MAX 512
195
196#define TASK_STATE_TO_CHAR_STR "RSDTtZXxKW"
197
198extern char ___assert_task_state[1 - 2*!!(
199 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
200
201/* Convenience macros for the sake of set_task_state */
202#define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
203#define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
204#define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED)
205
206/* Convenience macros for the sake of wake_up */
207#define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
208#define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
209
210/* get_task_state() */
211#define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \
212 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
213 __TASK_TRACED)
214
215#define task_is_traced(task) ((task->state & __TASK_TRACED) != 0)
216#define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0)
217#define task_is_dead(task) ((task)->exit_state != 0)
218#define task_is_stopped_or_traced(task) \
219 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
220#define task_contributes_to_load(task) \
221 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
222 (task->flags & PF_FREEZING) == 0)
223
224#define __set_task_state(tsk, state_value) \
225 do { (tsk)->state = (state_value); } while (0)
226#define set_task_state(tsk, state_value) \
227 set_mb((tsk)->state, (state_value))
228
229/*
230 * set_current_state() includes a barrier so that the write of current->state
231 * is correctly serialised wrt the caller's subsequent test of whether to
232 * actually sleep:
233 *
234 * set_current_state(TASK_UNINTERRUPTIBLE);
235 * if (do_i_need_to_sleep())
236 * schedule();
237 *
238 * If the caller does not need such serialisation then use __set_current_state()
239 */
240#define __set_current_state(state_value) \
241 do { current->state = (state_value); } while (0)
242#define set_current_state(state_value) \
243 set_mb(current->state, (state_value))
244
245/* Task command name length */
246#define TASK_COMM_LEN 16
247
248#include <linux/spinlock.h>
249
250/*
251 * This serializes "schedule()" and also protects
252 * the run-queue from deletions/modifications (but
253 * _adding_ to the beginning of the run-queue has
254 * a separate lock).
255 */
256extern rwlock_t tasklist_lock;
257extern spinlock_t mmlist_lock;
258
259struct task_struct;
260
261#ifdef CONFIG_PROVE_RCU
262extern int lockdep_tasklist_lock_is_held(void);
263#endif /* #ifdef CONFIG_PROVE_RCU */
264
265extern void sched_init(void);
266extern void sched_init_smp(void);
267extern asmlinkage void schedule_tail(struct task_struct *prev);
268extern void init_idle(struct task_struct *idle, int cpu);
269extern void init_idle_bootup_task(struct task_struct *idle);
270
271extern int runqueue_is_locked(int cpu);
272
273extern cpumask_var_t nohz_cpu_mask;
274#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
275extern void select_nohz_load_balancer(int stop_tick);
276extern int get_nohz_timer_target(void);
277#else
278static inline void select_nohz_load_balancer(int stop_tick) { }
279#endif
280
281/*
282 * Only dump TASK_* tasks. (0 for all tasks)
283 */
284extern void show_state_filter(unsigned long state_filter);
285
286static inline void show_state(void)
287{
288 show_state_filter(0);
289}
290
291extern void show_regs(struct pt_regs *);
292
293/*
294 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
295 * task), SP is the stack pointer of the first frame that should be shown in the back
296 * trace (or NULL if the entire call-chain of the task should be shown).
297 */
298extern void show_stack(struct task_struct *task, unsigned long *sp);
299
300void io_schedule(void);
301long io_schedule_timeout(long timeout);
302
303extern void cpu_init (void);
304extern void trap_init(void);
305extern void update_process_times(int user);
306extern void scheduler_tick(void);
307
308extern void sched_show_task(struct task_struct *p);
309
310#ifdef CONFIG_LOCKUP_DETECTOR
311extern void touch_softlockup_watchdog(void);
312extern void touch_softlockup_watchdog_sync(void);
313extern void touch_all_softlockup_watchdogs(void);
314extern int proc_dowatchdog_thresh(struct ctl_table *table, int write,
315 void __user *buffer,
316 size_t *lenp, loff_t *ppos);
317extern unsigned int softlockup_panic;
318extern int softlockup_thresh;
319#else
320static inline void touch_softlockup_watchdog(void)
321{
322}
323static inline void touch_softlockup_watchdog_sync(void)
324{
325}
326static inline void touch_all_softlockup_watchdogs(void)
327{
328}
329#endif
330
331#ifdef CONFIG_DETECT_HUNG_TASK
332extern unsigned int sysctl_hung_task_panic;
333extern unsigned long sysctl_hung_task_check_count;
334extern unsigned long sysctl_hung_task_timeout_secs;
335extern unsigned long sysctl_hung_task_warnings;
336extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
337 void __user *buffer,
338 size_t *lenp, loff_t *ppos);
339#else
340/* Avoid need for ifdefs elsewhere in the code */
341enum { sysctl_hung_task_timeout_secs = 0 };
342#endif
343
344/* Attach to any functions which should be ignored in wchan output. */
345#define __sched __attribute__((__section__(".sched.text")))
346
347/* Linker adds these: start and end of __sched functions */
348extern char __sched_text_start[], __sched_text_end[];
349
350/* Is this address in the __sched functions? */
351extern int in_sched_functions(unsigned long addr);
352
353#define MAX_SCHEDULE_TIMEOUT LONG_MAX
354extern signed long schedule_timeout(signed long timeout);
355extern signed long schedule_timeout_interruptible(signed long timeout);
356extern signed long schedule_timeout_killable(signed long timeout);
357extern signed long schedule_timeout_uninterruptible(signed long timeout);
358asmlinkage void schedule(void);
359extern int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner);
360
361struct nsproxy;
362struct user_namespace;
363
364/*
365 * Default maximum number of active map areas, this limits the number of vmas
366 * per mm struct. Users can overwrite this number by sysctl but there is a
367 * problem.
368 *
369 * When a program's coredump is generated as ELF format, a section is created
370 * per a vma. In ELF, the number of sections is represented in unsigned short.
371 * This means the number of sections should be smaller than 65535 at coredump.
372 * Because the kernel adds some informative sections to a image of program at
373 * generating coredump, we need some margin. The number of extra sections is
374 * 1-3 now and depends on arch. We use "5" as safe margin, here.
375 */
376#define MAPCOUNT_ELF_CORE_MARGIN (5)
377#define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
378
379extern int sysctl_max_map_count;
380
381#include <linux/aio.h>
382
383#ifdef CONFIG_MMU
384extern void arch_pick_mmap_layout(struct mm_struct *mm);
385extern unsigned long
386arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
387 unsigned long, unsigned long);
388extern unsigned long
389arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
390 unsigned long len, unsigned long pgoff,
391 unsigned long flags);
392extern void arch_unmap_area(struct mm_struct *, unsigned long);
393extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
394#else
395static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
396#endif
397
398
399extern void set_dumpable(struct mm_struct *mm, int value);
400extern int get_dumpable(struct mm_struct *mm);
401
402/* mm flags */
403/* dumpable bits */
404#define MMF_DUMPABLE 0 /* core dump is permitted */
405#define MMF_DUMP_SECURELY 1 /* core file is readable only by root */
406
407#define MMF_DUMPABLE_BITS 2
408#define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
409
410/* coredump filter bits */
411#define MMF_DUMP_ANON_PRIVATE 2
412#define MMF_DUMP_ANON_SHARED 3
413#define MMF_DUMP_MAPPED_PRIVATE 4
414#define MMF_DUMP_MAPPED_SHARED 5
415#define MMF_DUMP_ELF_HEADERS 6
416#define MMF_DUMP_HUGETLB_PRIVATE 7
417#define MMF_DUMP_HUGETLB_SHARED 8
418
419#define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS
420#define MMF_DUMP_FILTER_BITS 7
421#define MMF_DUMP_FILTER_MASK \
422 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
423#define MMF_DUMP_FILTER_DEFAULT \
424 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\
425 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
426
427#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
428# define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS)
429#else
430# define MMF_DUMP_MASK_DEFAULT_ELF 0
431#endif
432 /* leave room for more dump flags */
433#define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */
434
435#define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
436
437struct sighand_struct {
438 atomic_t count;
439 struct k_sigaction action[_NSIG];
440 spinlock_t siglock;
441 wait_queue_head_t signalfd_wqh;
442};
443
444struct pacct_struct {
445 int ac_flag;
446 long ac_exitcode;
447 unsigned long ac_mem;
448 cputime_t ac_utime, ac_stime;
449 unsigned long ac_minflt, ac_majflt;
450};
451
452struct cpu_itimer {
453 cputime_t expires;
454 cputime_t incr;
455 u32 error;
456 u32 incr_error;
457};
458
459/**
460 * struct task_cputime - collected CPU time counts
461 * @utime: time spent in user mode, in &cputime_t units
462 * @stime: time spent in kernel mode, in &cputime_t units
463 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds
464 *
465 * This structure groups together three kinds of CPU time that are
466 * tracked for threads and thread groups. Most things considering
467 * CPU time want to group these counts together and treat all three
468 * of them in parallel.
469 */
470struct task_cputime {
471 cputime_t utime;
472 cputime_t stime;
473 unsigned long long sum_exec_runtime;
474};
475/* Alternate field names when used to cache expirations. */
476#define prof_exp stime
477#define virt_exp utime
478#define sched_exp sum_exec_runtime
479
480#define INIT_CPUTIME \
481 (struct task_cputime) { \
482 .utime = cputime_zero, \
483 .stime = cputime_zero, \
484 .sum_exec_runtime = 0, \
485 }
486
487/*
488 * Disable preemption until the scheduler is running.
489 * Reset by start_kernel()->sched_init()->init_idle().
490 *
491 * We include PREEMPT_ACTIVE to avoid cond_resched() from working
492 * before the scheduler is active -- see should_resched().
493 */
494#define INIT_PREEMPT_COUNT (1 + PREEMPT_ACTIVE)
495
496/**
497 * struct thread_group_cputimer - thread group interval timer counts
498 * @cputime: thread group interval timers.
499 * @running: non-zero when there are timers running and
500 * @cputime receives updates.
501 * @lock: lock for fields in this struct.
502 *
503 * This structure contains the version of task_cputime, above, that is
504 * used for thread group CPU timer calculations.
505 */
506struct thread_group_cputimer {
507 struct task_cputime cputime;
508 int running;
509 spinlock_t lock;
510};
511
512/*
513 * NOTE! "signal_struct" does not have it's own
514 * locking, because a shared signal_struct always
515 * implies a shared sighand_struct, so locking
516 * sighand_struct is always a proper superset of
517 * the locking of signal_struct.
518 */
519struct signal_struct {
520 atomic_t sigcnt;
521 atomic_t live;
522 int nr_threads;
523
524 wait_queue_head_t wait_chldexit; /* for wait4() */
525
526 /* current thread group signal load-balancing target: */
527 struct task_struct *curr_target;
528
529 /* shared signal handling: */
530 struct sigpending shared_pending;
531
532 /* thread group exit support */
533 int group_exit_code;
534 /* overloaded:
535 * - notify group_exit_task when ->count is equal to notify_count
536 * - everyone except group_exit_task is stopped during signal delivery
537 * of fatal signals, group_exit_task processes the signal.
538 */
539 int notify_count;
540 struct task_struct *group_exit_task;
541
542 /* thread group stop support, overloads group_exit_code too */
543 int group_stop_count;
544 unsigned int flags; /* see SIGNAL_* flags below */
545
546 /* POSIX.1b Interval Timers */
547 struct list_head posix_timers;
548
549 /* ITIMER_REAL timer for the process */
550 struct hrtimer real_timer;
551 struct pid *leader_pid;
552 ktime_t it_real_incr;
553
554 /*
555 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
556 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
557 * values are defined to 0 and 1 respectively
558 */
559 struct cpu_itimer it[2];
560
561 /*
562 * Thread group totals for process CPU timers.
563 * See thread_group_cputimer(), et al, for details.
564 */
565 struct thread_group_cputimer cputimer;
566
567 /* Earliest-expiration cache. */
568 struct task_cputime cputime_expires;
569
570 struct list_head cpu_timers[3];
571
572 struct pid *tty_old_pgrp;
573
574 /* boolean value for session group leader */
575 int leader;
576
577 struct tty_struct *tty; /* NULL if no tty */
578
579 /*
580 * Cumulative resource counters for dead threads in the group,
581 * and for reaped dead child processes forked by this group.
582 * Live threads maintain their own counters and add to these
583 * in __exit_signal, except for the group leader.
584 */
585 cputime_t utime, stime, cutime, cstime;
586 cputime_t gtime;
587 cputime_t cgtime;
588#ifndef CONFIG_VIRT_CPU_ACCOUNTING
589 cputime_t prev_utime, prev_stime;
590#endif
591 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
592 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
593 unsigned long inblock, oublock, cinblock, coublock;
594 unsigned long maxrss, cmaxrss;
595 struct task_io_accounting ioac;
596
597 /*
598 * Cumulative ns of schedule CPU time fo dead threads in the
599 * group, not including a zombie group leader, (This only differs
600 * from jiffies_to_ns(utime + stime) if sched_clock uses something
601 * other than jiffies.)
602 */
603 unsigned long long sum_sched_runtime;
604
605 /*
606 * We don't bother to synchronize most readers of this at all,
607 * because there is no reader checking a limit that actually needs
608 * to get both rlim_cur and rlim_max atomically, and either one
609 * alone is a single word that can safely be read normally.
610 * getrlimit/setrlimit use task_lock(current->group_leader) to
611 * protect this instead of the siglock, because they really
612 * have no need to disable irqs.
613 */
614 struct rlimit rlim[RLIM_NLIMITS];
615
616#ifdef CONFIG_BSD_PROCESS_ACCT
617 struct pacct_struct pacct; /* per-process accounting information */
618#endif
619#ifdef CONFIG_TASKSTATS
620 struct taskstats *stats;
621#endif
622#ifdef CONFIG_AUDIT
623 unsigned audit_tty;
624 struct tty_audit_buf *tty_audit_buf;
625#endif
626
627 int oom_adj; /* OOM kill score adjustment (bit shift) */
628 int oom_score_adj; /* OOM kill score adjustment */
629
630 struct mutex cred_guard_mutex; /* guard against foreign influences on
631 * credential calculations
632 * (notably. ptrace) */
633};
634
635/* Context switch must be unlocked if interrupts are to be enabled */
636#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
637# define __ARCH_WANT_UNLOCKED_CTXSW
638#endif
639
640/*
641 * Bits in flags field of signal_struct.
642 */
643#define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */
644#define SIGNAL_STOP_DEQUEUED 0x00000002 /* stop signal dequeued */
645#define SIGNAL_STOP_CONTINUED 0x00000004 /* SIGCONT since WCONTINUED reap */
646#define SIGNAL_GROUP_EXIT 0x00000008 /* group exit in progress */
647/*
648 * Pending notifications to parent.
649 */
650#define SIGNAL_CLD_STOPPED 0x00000010
651#define SIGNAL_CLD_CONTINUED 0x00000020
652#define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
653
654#define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */
655
656/* If true, all threads except ->group_exit_task have pending SIGKILL */
657static inline int signal_group_exit(const struct signal_struct *sig)
658{
659 return (sig->flags & SIGNAL_GROUP_EXIT) ||
660 (sig->group_exit_task != NULL);
661}
662
663/*
664 * Some day this will be a full-fledged user tracking system..
665 */
666struct user_struct {
667 atomic_t __count; /* reference count */
668 atomic_t processes; /* How many processes does this user have? */
669 atomic_t files; /* How many open files does this user have? */
670 atomic_t sigpending; /* How many pending signals does this user have? */
671#ifdef CONFIG_INOTIFY_USER
672 atomic_t inotify_watches; /* How many inotify watches does this user have? */
673 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */
674#endif
675#ifdef CONFIG_EPOLL
676 atomic_t epoll_watches; /* The number of file descriptors currently watched */
677#endif
678#ifdef CONFIG_POSIX_MQUEUE
679 /* protected by mq_lock */
680 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
681#endif
682 unsigned long locked_shm; /* How many pages of mlocked shm ? */
683
684#ifdef CONFIG_KEYS
685 struct key *uid_keyring; /* UID specific keyring */
686 struct key *session_keyring; /* UID's default session keyring */
687#endif
688
689 /* Hash table maintenance information */
690 struct hlist_node uidhash_node;
691 uid_t uid;
692 struct user_namespace *user_ns;
693
694#ifdef CONFIG_PERF_EVENTS
695 atomic_long_t locked_vm;
696#endif
697};
698
699extern int uids_sysfs_init(void);
700
701extern struct user_struct *find_user(uid_t);
702
703extern struct user_struct root_user;
704#define INIT_USER (&root_user)
705
706
707struct backing_dev_info;
708struct reclaim_state;
709
710#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
711struct sched_info {
712 /* cumulative counters */
713 unsigned long pcount; /* # of times run on this cpu */
714 unsigned long long run_delay; /* time spent waiting on a runqueue */
715
716 /* timestamps */
717 unsigned long long last_arrival,/* when we last ran on a cpu */
718 last_queued; /* when we were last queued to run */
719#ifdef CONFIG_SCHEDSTATS
720 /* BKL stats */
721 unsigned int bkl_count;
722#endif
723};
724#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
725
726#ifdef CONFIG_TASK_DELAY_ACCT
727struct task_delay_info {
728 spinlock_t lock;
729 unsigned int flags; /* Private per-task flags */
730
731 /* For each stat XXX, add following, aligned appropriately
732 *
733 * struct timespec XXX_start, XXX_end;
734 * u64 XXX_delay;
735 * u32 XXX_count;
736 *
737 * Atomicity of updates to XXX_delay, XXX_count protected by
738 * single lock above (split into XXX_lock if contention is an issue).
739 */
740
741 /*
742 * XXX_count is incremented on every XXX operation, the delay
743 * associated with the operation is added to XXX_delay.
744 * XXX_delay contains the accumulated delay time in nanoseconds.
745 */
746 struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */
747 u64 blkio_delay; /* wait for sync block io completion */
748 u64 swapin_delay; /* wait for swapin block io completion */
749 u32 blkio_count; /* total count of the number of sync block */
750 /* io operations performed */
751 u32 swapin_count; /* total count of the number of swapin block */
752 /* io operations performed */
753
754 struct timespec freepages_start, freepages_end;
755 u64 freepages_delay; /* wait for memory reclaim */
756 u32 freepages_count; /* total count of memory reclaim */
757};
758#endif /* CONFIG_TASK_DELAY_ACCT */
759
760static inline int sched_info_on(void)
761{
762#ifdef CONFIG_SCHEDSTATS
763 return 1;
764#elif defined(CONFIG_TASK_DELAY_ACCT)
765 extern int delayacct_on;
766 return delayacct_on;
767#else
768 return 0;
769#endif
770}
771
772enum cpu_idle_type {
773 CPU_IDLE,
774 CPU_NOT_IDLE,
775 CPU_NEWLY_IDLE,
776 CPU_MAX_IDLE_TYPES
777};
778
779/*
780 * sched-domains (multiprocessor balancing) declarations:
781 */
782
783/*
784 * Increase resolution of nice-level calculations:
785 */
786#define SCHED_LOAD_SHIFT 10
787#define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT)
788
789#define SCHED_LOAD_SCALE_FUZZ SCHED_LOAD_SCALE
790
791#ifdef CONFIG_SMP
792#define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */
793#define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */
794#define SD_BALANCE_EXEC 0x0004 /* Balance on exec */
795#define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */
796#define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */
797#define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */
798#define SD_PREFER_LOCAL 0x0040 /* Prefer to keep tasks local to this domain */
799#define SD_SHARE_CPUPOWER 0x0080 /* Domain members share cpu power */
800#define SD_POWERSAVINGS_BALANCE 0x0100 /* Balance for power savings */
801#define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */
802#define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */
803#define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */
804#define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */
805
806enum powersavings_balance_level {
807 POWERSAVINGS_BALANCE_NONE = 0, /* No power saving load balance */
808 POWERSAVINGS_BALANCE_BASIC, /* Fill one thread/core/package
809 * first for long running threads
810 */
811 POWERSAVINGS_BALANCE_WAKEUP, /* Also bias task wakeups to semi-idle
812 * cpu package for power savings
813 */
814 MAX_POWERSAVINGS_BALANCE_LEVELS
815};
816
817extern int sched_mc_power_savings, sched_smt_power_savings;
818
819static inline int sd_balance_for_mc_power(void)
820{
821 if (sched_smt_power_savings)
822 return SD_POWERSAVINGS_BALANCE;
823
824 if (!sched_mc_power_savings)
825 return SD_PREFER_SIBLING;
826
827 return 0;
828}
829
830static inline int sd_balance_for_package_power(void)
831{
832 if (sched_mc_power_savings | sched_smt_power_savings)
833 return SD_POWERSAVINGS_BALANCE;
834
835 return SD_PREFER_SIBLING;
836}
837
838extern int __weak arch_sd_sibiling_asym_packing(void);
839
840/*
841 * Optimise SD flags for power savings:
842 * SD_BALANCE_NEWIDLE helps agressive task consolidation and power savings.
843 * Keep default SD flags if sched_{smt,mc}_power_saving=0
844 */
845
846static inline int sd_power_saving_flags(void)
847{
848 if (sched_mc_power_savings | sched_smt_power_savings)
849 return SD_BALANCE_NEWIDLE;
850
851 return 0;
852}
853
854struct sched_group {
855 struct sched_group *next; /* Must be a circular list */
856
857 /*
858 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
859 * single CPU.
860 */
861 unsigned int cpu_power, cpu_power_orig;
862
863 /*
864 * The CPUs this group covers.
865 *
866 * NOTE: this field is variable length. (Allocated dynamically
867 * by attaching extra space to the end of the structure,
868 * depending on how many CPUs the kernel has booted up with)
869 *
870 * It is also be embedded into static data structures at build
871 * time. (See 'struct static_sched_group' in kernel/sched.c)
872 */
873 unsigned long cpumask[0];
874};
875
876static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
877{
878 return to_cpumask(sg->cpumask);
879}
880
881enum sched_domain_level {
882 SD_LV_NONE = 0,
883 SD_LV_SIBLING,
884 SD_LV_MC,
885 SD_LV_BOOK,
886 SD_LV_CPU,
887 SD_LV_NODE,
888 SD_LV_ALLNODES,
889 SD_LV_MAX
890};
891
892struct sched_domain_attr {
893 int relax_domain_level;
894};
895
896#define SD_ATTR_INIT (struct sched_domain_attr) { \
897 .relax_domain_level = -1, \
898}
899
900struct sched_domain {
901 /* These fields must be setup */
902 struct sched_domain *parent; /* top domain must be null terminated */
903 struct sched_domain *child; /* bottom domain must be null terminated */
904 struct sched_group *groups; /* the balancing groups of the domain */
905 unsigned long min_interval; /* Minimum balance interval ms */
906 unsigned long max_interval; /* Maximum balance interval ms */
907 unsigned int busy_factor; /* less balancing by factor if busy */
908 unsigned int imbalance_pct; /* No balance until over watermark */
909 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */
910 unsigned int busy_idx;
911 unsigned int idle_idx;
912 unsigned int newidle_idx;
913 unsigned int wake_idx;
914 unsigned int forkexec_idx;
915 unsigned int smt_gain;
916 int flags; /* See SD_* */
917 enum sched_domain_level level;
918
919 /* Runtime fields. */
920 unsigned long last_balance; /* init to jiffies. units in jiffies */
921 unsigned int balance_interval; /* initialise to 1. units in ms. */
922 unsigned int nr_balance_failed; /* initialise to 0 */
923
924 u64 last_update;
925
926#ifdef CONFIG_SCHEDSTATS
927 /* load_balance() stats */
928 unsigned int lb_count[CPU_MAX_IDLE_TYPES];
929 unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
930 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
931 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
932 unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
933 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
934 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
935 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
936
937 /* Active load balancing */
938 unsigned int alb_count;
939 unsigned int alb_failed;
940 unsigned int alb_pushed;
941
942 /* SD_BALANCE_EXEC stats */
943 unsigned int sbe_count;
944 unsigned int sbe_balanced;
945 unsigned int sbe_pushed;
946
947 /* SD_BALANCE_FORK stats */
948 unsigned int sbf_count;
949 unsigned int sbf_balanced;
950 unsigned int sbf_pushed;
951
952 /* try_to_wake_up() stats */
953 unsigned int ttwu_wake_remote;
954 unsigned int ttwu_move_affine;
955 unsigned int ttwu_move_balance;
956#endif
957#ifdef CONFIG_SCHED_DEBUG
958 char *name;
959#endif
960
961 unsigned int span_weight;
962 /*
963 * Span of all CPUs in this domain.
964 *
965 * NOTE: this field is variable length. (Allocated dynamically
966 * by attaching extra space to the end of the structure,
967 * depending on how many CPUs the kernel has booted up with)
968 *
969 * It is also be embedded into static data structures at build
970 * time. (See 'struct static_sched_domain' in kernel/sched.c)
971 */
972 unsigned long span[0];
973};
974
975static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
976{
977 return to_cpumask(sd->span);
978}
979
980extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
981 struct sched_domain_attr *dattr_new);
982
983/* Allocate an array of sched domains, for partition_sched_domains(). */
984cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
985void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
986
987/* Test a flag in parent sched domain */
988static inline int test_sd_parent(struct sched_domain *sd, int flag)
989{
990 if (sd->parent && (sd->parent->flags & flag))
991 return 1;
992
993 return 0;
994}
995
996unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu);
997unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu);
998
999#else /* CONFIG_SMP */
1000
1001struct sched_domain_attr;
1002
1003static inline void
1004partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1005 struct sched_domain_attr *dattr_new)
1006{
1007}
1008#endif /* !CONFIG_SMP */
1009
1010
1011struct io_context; /* See blkdev.h */
1012
1013
1014#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1015extern void prefetch_stack(struct task_struct *t);
1016#else
1017static inline void prefetch_stack(struct task_struct *t) { }
1018#endif
1019
1020struct audit_context; /* See audit.c */
1021struct mempolicy;
1022struct pipe_inode_info;
1023struct uts_namespace;
1024
1025struct rq;
1026struct sched_domain;
1027
1028/*
1029 * wake flags
1030 */
1031#define WF_SYNC 0x01 /* waker goes to sleep after wakup */
1032#define WF_FORK 0x02 /* child wakeup after fork */
1033
1034#define ENQUEUE_WAKEUP 1
1035#define ENQUEUE_WAKING 2
1036#define ENQUEUE_HEAD 4
1037
1038#define DEQUEUE_SLEEP 1
1039
1040struct sched_class {
1041 const struct sched_class *next;
1042
1043 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1044 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1045 void (*yield_task) (struct rq *rq);
1046
1047 void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
1048
1049 struct task_struct * (*pick_next_task) (struct rq *rq);
1050 void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1051
1052#ifdef CONFIG_SMP
1053 int (*select_task_rq)(struct rq *rq, struct task_struct *p,
1054 int sd_flag, int flags);
1055
1056 void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
1057 void (*post_schedule) (struct rq *this_rq);
1058 void (*task_waking) (struct rq *this_rq, struct task_struct *task);
1059 void (*task_woken) (struct rq *this_rq, struct task_struct *task);
1060
1061 void (*set_cpus_allowed)(struct task_struct *p,
1062 const struct cpumask *newmask);
1063
1064 void (*rq_online)(struct rq *rq);
1065 void (*rq_offline)(struct rq *rq);
1066#endif
1067
1068 void (*set_curr_task) (struct rq *rq);
1069 void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1070 void (*task_fork) (struct task_struct *p);
1071
1072 void (*switched_from) (struct rq *this_rq, struct task_struct *task,
1073 int running);
1074 void (*switched_to) (struct rq *this_rq, struct task_struct *task,
1075 int running);
1076 void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1077 int oldprio, int running);
1078
1079 unsigned int (*get_rr_interval) (struct rq *rq,
1080 struct task_struct *task);
1081
1082#ifdef CONFIG_FAIR_GROUP_SCHED
1083 void (*task_move_group) (struct task_struct *p, int on_rq);
1084#endif
1085};
1086
1087struct load_weight {
1088 unsigned long weight, inv_weight;
1089};
1090
1091#ifdef CONFIG_SCHEDSTATS
1092struct sched_statistics {
1093 u64 wait_start;
1094 u64 wait_max;
1095 u64 wait_count;
1096 u64 wait_sum;
1097 u64 iowait_count;
1098 u64 iowait_sum;
1099
1100 u64 sleep_start;
1101 u64 sleep_max;
1102 s64 sum_sleep_runtime;
1103
1104 u64 block_start;
1105 u64 block_max;
1106 u64 exec_max;
1107 u64 slice_max;
1108
1109 u64 nr_migrations_cold;
1110 u64 nr_failed_migrations_affine;
1111 u64 nr_failed_migrations_running;
1112 u64 nr_failed_migrations_hot;
1113 u64 nr_forced_migrations;
1114
1115 u64 nr_wakeups;
1116 u64 nr_wakeups_sync;
1117 u64 nr_wakeups_migrate;
1118 u64 nr_wakeups_local;
1119 u64 nr_wakeups_remote;
1120 u64 nr_wakeups_affine;
1121 u64 nr_wakeups_affine_attempts;
1122 u64 nr_wakeups_passive;
1123 u64 nr_wakeups_idle;
1124};
1125#endif
1126
1127struct sched_entity {
1128 struct load_weight load; /* for load-balancing */
1129 struct rb_node run_node;
1130 struct list_head group_node;
1131 unsigned int on_rq;
1132
1133 u64 exec_start;
1134 u64 sum_exec_runtime;
1135 u64 vruntime;
1136 u64 prev_sum_exec_runtime;
1137
1138 u64 nr_migrations;
1139
1140#ifdef CONFIG_SCHEDSTATS
1141 struct sched_statistics statistics;
1142#endif
1143
1144#ifdef CONFIG_FAIR_GROUP_SCHED
1145 struct sched_entity *parent;
1146 /* rq on which this entity is (to be) queued: */
1147 struct cfs_rq *cfs_rq;
1148 /* rq "owned" by this entity/group: */
1149 struct cfs_rq *my_q;
1150#endif
1151};
1152
1153struct sched_rt_entity {
1154 struct list_head run_list;
1155 unsigned long timeout;
1156 unsigned int time_slice;
1157 int nr_cpus_allowed;
1158
1159 struct sched_rt_entity *back;
1160#ifdef CONFIG_RT_GROUP_SCHED
1161 struct sched_rt_entity *parent;
1162 /* rq on which this entity is (to be) queued: */
1163 struct rt_rq *rt_rq;
1164 /* rq "owned" by this entity/group: */
1165 struct rt_rq *my_q;
1166#endif
1167};
1168
1169struct rcu_node;
1170
1171enum perf_event_task_context {
1172 perf_invalid_context = -1,
1173 perf_hw_context = 0,
1174 perf_sw_context,
1175 perf_nr_task_contexts,
1176};
1177
1178struct task_struct {
1179 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
1180 void *stack;
1181 atomic_t usage;
1182 unsigned int flags; /* per process flags, defined below */
1183 unsigned int ptrace;
1184
1185 int lock_depth; /* BKL lock depth */
1186
1187#ifdef CONFIG_SMP
1188#ifdef __ARCH_WANT_UNLOCKED_CTXSW
1189 int oncpu;
1190#endif
1191#endif
1192
1193 int prio, static_prio, normal_prio;
1194 unsigned int rt_priority;
1195 const struct sched_class *sched_class;
1196 struct sched_entity se;
1197 struct sched_rt_entity rt;
1198
1199#ifdef CONFIG_PREEMPT_NOTIFIERS
1200 /* list of struct preempt_notifier: */
1201 struct hlist_head preempt_notifiers;
1202#endif
1203
1204 /*
1205 * fpu_counter contains the number of consecutive context switches
1206 * that the FPU is used. If this is over a threshold, the lazy fpu
1207 * saving becomes unlazy to save the trap. This is an unsigned char
1208 * so that after 256 times the counter wraps and the behavior turns
1209 * lazy again; this to deal with bursty apps that only use FPU for
1210 * a short time
1211 */
1212 unsigned char fpu_counter;
1213#ifdef CONFIG_BLK_DEV_IO_TRACE
1214 unsigned int btrace_seq;
1215#endif
1216
1217 unsigned int policy;
1218 cpumask_t cpus_allowed;
1219
1220#ifdef CONFIG_PREEMPT_RCU
1221 int rcu_read_lock_nesting;
1222 char rcu_read_unlock_special;
1223 struct list_head rcu_node_entry;
1224#endif /* #ifdef CONFIG_PREEMPT_RCU */
1225#ifdef CONFIG_TREE_PREEMPT_RCU
1226 struct rcu_node *rcu_blocked_node;
1227#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1228
1229#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1230 struct sched_info sched_info;
1231#endif
1232
1233 struct list_head tasks;
1234 struct plist_node pushable_tasks;
1235
1236 struct mm_struct *mm, *active_mm;
1237#if defined(SPLIT_RSS_COUNTING)
1238 struct task_rss_stat rss_stat;
1239#endif
1240/* task state */
1241 int exit_state;
1242 int exit_code, exit_signal;
1243 int pdeath_signal; /* The signal sent when the parent dies */
1244 /* ??? */
1245 unsigned int personality;
1246 unsigned did_exec:1;
1247 unsigned in_execve:1; /* Tell the LSMs that the process is doing an
1248 * execve */
1249 unsigned in_iowait:1;
1250
1251
1252 /* Revert to default priority/policy when forking */
1253 unsigned sched_reset_on_fork:1;
1254
1255 pid_t pid;
1256 pid_t tgid;
1257
1258#ifdef CONFIG_CC_STACKPROTECTOR
1259 /* Canary value for the -fstack-protector gcc feature */
1260 unsigned long stack_canary;
1261#endif
1262
1263 /*
1264 * pointers to (original) parent process, youngest child, younger sibling,
1265 * older sibling, respectively. (p->father can be replaced with
1266 * p->real_parent->pid)
1267 */
1268 struct task_struct *real_parent; /* real parent process */
1269 struct task_struct *parent; /* recipient of SIGCHLD, wait4() reports */
1270 /*
1271 * children/sibling forms the list of my natural children
1272 */
1273 struct list_head children; /* list of my children */
1274 struct list_head sibling; /* linkage in my parent's children list */
1275 struct task_struct *group_leader; /* threadgroup leader */
1276
1277 /*
1278 * ptraced is the list of tasks this task is using ptrace on.
1279 * This includes both natural children and PTRACE_ATTACH targets.
1280 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1281 */
1282 struct list_head ptraced;
1283 struct list_head ptrace_entry;
1284
1285 /* PID/PID hash table linkage. */
1286 struct pid_link pids[PIDTYPE_MAX];
1287 struct list_head thread_group;
1288
1289 struct completion *vfork_done; /* for vfork() */
1290 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
1291 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
1292
1293 cputime_t utime, stime, utimescaled, stimescaled;
1294 cputime_t gtime;
1295#ifndef CONFIG_VIRT_CPU_ACCOUNTING
1296 cputime_t prev_utime, prev_stime;
1297#endif
1298 unsigned long nvcsw, nivcsw; /* context switch counts */
1299 struct timespec start_time; /* monotonic time */
1300 struct timespec real_start_time; /* boot based time */
1301/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1302 unsigned long min_flt, maj_flt;
1303
1304 struct task_cputime cputime_expires;
1305 struct list_head cpu_timers[3];
1306
1307/* process credentials */
1308 const struct cred __rcu *real_cred; /* objective and real subjective task
1309 * credentials (COW) */
1310 const struct cred __rcu *cred; /* effective (overridable) subjective task
1311 * credentials (COW) */
1312 struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */
1313
1314 char comm[TASK_COMM_LEN]; /* executable name excluding path
1315 - access with [gs]et_task_comm (which lock
1316 it with task_lock())
1317 - initialized normally by setup_new_exec */
1318/* file system info */
1319 int link_count, total_link_count;
1320#ifdef CONFIG_SYSVIPC
1321/* ipc stuff */
1322 struct sysv_sem sysvsem;
1323#endif
1324#ifdef CONFIG_DETECT_HUNG_TASK
1325/* hung task detection */
1326 unsigned long last_switch_count;
1327#endif
1328/* CPU-specific state of this task */
1329 struct thread_struct thread;
1330/* filesystem information */
1331 struct fs_struct *fs;
1332/* open file information */
1333 struct files_struct *files;
1334/* namespaces */
1335 struct nsproxy *nsproxy;
1336/* signal handlers */
1337 struct signal_struct *signal;
1338 struct sighand_struct *sighand;
1339
1340 sigset_t blocked, real_blocked;
1341 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
1342 struct sigpending pending;
1343
1344 unsigned long sas_ss_sp;
1345 size_t sas_ss_size;
1346 int (*notifier)(void *priv);
1347 void *notifier_data;
1348 sigset_t *notifier_mask;
1349 struct audit_context *audit_context;
1350#ifdef CONFIG_AUDITSYSCALL
1351 uid_t loginuid;
1352 unsigned int sessionid;
1353#endif
1354 seccomp_t seccomp;
1355
1356/* Thread group tracking */
1357 u32 parent_exec_id;
1358 u32 self_exec_id;
1359/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1360 * mempolicy */
1361 spinlock_t alloc_lock;
1362
1363#ifdef CONFIG_GENERIC_HARDIRQS
1364 /* IRQ handler threads */
1365 struct irqaction *irqaction;
1366#endif
1367
1368 /* Protection of the PI data structures: */
1369 raw_spinlock_t pi_lock;
1370
1371#ifdef CONFIG_RT_MUTEXES
1372 /* PI waiters blocked on a rt_mutex held by this task */
1373 struct plist_head pi_waiters;
1374 /* Deadlock detection and priority inheritance handling */
1375 struct rt_mutex_waiter *pi_blocked_on;
1376#endif
1377
1378#ifdef CONFIG_DEBUG_MUTEXES
1379 /* mutex deadlock detection */
1380 struct mutex_waiter *blocked_on;
1381#endif
1382#ifdef CONFIG_TRACE_IRQFLAGS
1383 unsigned int irq_events;
1384 unsigned long hardirq_enable_ip;
1385 unsigned long hardirq_disable_ip;
1386 unsigned int hardirq_enable_event;
1387 unsigned int hardirq_disable_event;
1388 int hardirqs_enabled;
1389 int hardirq_context;
1390 unsigned long softirq_disable_ip;
1391 unsigned long softirq_enable_ip;
1392 unsigned int softirq_disable_event;
1393 unsigned int softirq_enable_event;
1394 int softirqs_enabled;
1395 int softirq_context;
1396#endif
1397#ifdef CONFIG_LOCKDEP
1398# define MAX_LOCK_DEPTH 48UL
1399 u64 curr_chain_key;
1400 int lockdep_depth;
1401 unsigned int lockdep_recursion;
1402 struct held_lock held_locks[MAX_LOCK_DEPTH];
1403 gfp_t lockdep_reclaim_gfp;
1404#endif
1405
1406/* journalling filesystem info */
1407 void *journal_info;
1408
1409/* stacked block device info */
1410 struct bio_list *bio_list;
1411
1412/* VM state */
1413 struct reclaim_state *reclaim_state;
1414
1415 struct backing_dev_info *backing_dev_info;
1416
1417 struct io_context *io_context;
1418
1419 unsigned long ptrace_message;
1420 siginfo_t *last_siginfo; /* For ptrace use. */
1421 struct task_io_accounting ioac;
1422#if defined(CONFIG_TASK_XACCT)
1423 u64 acct_rss_mem1; /* accumulated rss usage */
1424 u64 acct_vm_mem1; /* accumulated virtual memory usage */
1425 cputime_t acct_timexpd; /* stime + utime since last update */
1426#endif
1427#ifdef CONFIG_CPUSETS
1428 nodemask_t mems_allowed; /* Protected by alloc_lock */
1429 int mems_allowed_change_disable;
1430 int cpuset_mem_spread_rotor;
1431 int cpuset_slab_spread_rotor;
1432#endif
1433#ifdef CONFIG_CGROUPS
1434 /* Control Group info protected by css_set_lock */
1435 struct css_set __rcu *cgroups;
1436 /* cg_list protected by css_set_lock and tsk->alloc_lock */
1437 struct list_head cg_list;
1438#endif
1439#ifdef CONFIG_FUTEX
1440 struct robust_list_head __user *robust_list;
1441#ifdef CONFIG_COMPAT
1442 struct compat_robust_list_head __user *compat_robust_list;
1443#endif
1444 struct list_head pi_state_list;
1445 struct futex_pi_state *pi_state_cache;
1446#endif
1447#ifdef CONFIG_PERF_EVENTS
1448 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1449 struct mutex perf_event_mutex;
1450 struct list_head perf_event_list;
1451#endif
1452#ifdef CONFIG_NUMA
1453 struct mempolicy *mempolicy; /* Protected by alloc_lock */
1454 short il_next;
1455#endif
1456 atomic_t fs_excl; /* holding fs exclusive resources */
1457 struct rcu_head rcu;
1458
1459 /*
1460 * cache last used pipe for splice
1461 */
1462 struct pipe_inode_info *splice_pipe;
1463#ifdef CONFIG_TASK_DELAY_ACCT
1464 struct task_delay_info *delays;
1465#endif
1466#ifdef CONFIG_FAULT_INJECTION
1467 int make_it_fail;
1468#endif
1469 struct prop_local_single dirties;
1470#ifdef CONFIG_LATENCYTOP
1471 int latency_record_count;
1472 struct latency_record latency_record[LT_SAVECOUNT];
1473#endif
1474 /*
1475 * time slack values; these are used to round up poll() and
1476 * select() etc timeout values. These are in nanoseconds.
1477 */
1478 unsigned long timer_slack_ns;
1479 unsigned long default_timer_slack_ns;
1480
1481 struct list_head *scm_work_list;
1482#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1483 /* Index of current stored address in ret_stack */
1484 int curr_ret_stack;
1485 /* Stack of return addresses for return function tracing */
1486 struct ftrace_ret_stack *ret_stack;
1487 /* time stamp for last schedule */
1488 unsigned long long ftrace_timestamp;
1489 /*
1490 * Number of functions that haven't been traced
1491 * because of depth overrun.
1492 */
1493 atomic_t trace_overrun;
1494 /* Pause for the tracing */
1495 atomic_t tracing_graph_pause;
1496#endif
1497#ifdef CONFIG_TRACING
1498 /* state flags for use by tracers */
1499 unsigned long trace;
1500 /* bitmask of trace recursion */
1501 unsigned long trace_recursion;
1502#endif /* CONFIG_TRACING */
1503#ifdef CONFIG_CGROUP_MEM_RES_CTLR /* memcg uses this to do batch job */
1504 struct memcg_batch_info {
1505 int do_batch; /* incremented when batch uncharge started */
1506 struct mem_cgroup *memcg; /* target memcg of uncharge */
1507 unsigned long bytes; /* uncharged usage */
1508 unsigned long memsw_bytes; /* uncharged mem+swap usage */
1509 } memcg_batch;
1510#endif
1511};
1512
1513/* Future-safe accessor for struct task_struct's cpus_allowed. */
1514#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1515
1516/*
1517 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1518 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1519 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1520 * values are inverted: lower p->prio value means higher priority.
1521 *
1522 * The MAX_USER_RT_PRIO value allows the actual maximum
1523 * RT priority to be separate from the value exported to
1524 * user-space. This allows kernel threads to set their
1525 * priority to a value higher than any user task. Note:
1526 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1527 */
1528
1529#define MAX_USER_RT_PRIO 100
1530#define MAX_RT_PRIO MAX_USER_RT_PRIO
1531
1532#define MAX_PRIO (MAX_RT_PRIO + 40)
1533#define DEFAULT_PRIO (MAX_RT_PRIO + 20)
1534
1535static inline int rt_prio(int prio)
1536{
1537 if (unlikely(prio < MAX_RT_PRIO))
1538 return 1;
1539 return 0;
1540}
1541
1542static inline int rt_task(struct task_struct *p)
1543{
1544 return rt_prio(p->prio);
1545}
1546
1547static inline struct pid *task_pid(struct task_struct *task)
1548{
1549 return task->pids[PIDTYPE_PID].pid;
1550}
1551
1552static inline struct pid *task_tgid(struct task_struct *task)
1553{
1554 return task->group_leader->pids[PIDTYPE_PID].pid;
1555}
1556
1557/*
1558 * Without tasklist or rcu lock it is not safe to dereference
1559 * the result of task_pgrp/task_session even if task == current,
1560 * we can race with another thread doing sys_setsid/sys_setpgid.
1561 */
1562static inline struct pid *task_pgrp(struct task_struct *task)
1563{
1564 return task->group_leader->pids[PIDTYPE_PGID].pid;
1565}
1566
1567static inline struct pid *task_session(struct task_struct *task)
1568{
1569 return task->group_leader->pids[PIDTYPE_SID].pid;
1570}
1571
1572struct pid_namespace;
1573
1574/*
1575 * the helpers to get the task's different pids as they are seen
1576 * from various namespaces
1577 *
1578 * task_xid_nr() : global id, i.e. the id seen from the init namespace;
1579 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of
1580 * current.
1581 * task_xid_nr_ns() : id seen from the ns specified;
1582 *
1583 * set_task_vxid() : assigns a virtual id to a task;
1584 *
1585 * see also pid_nr() etc in include/linux/pid.h
1586 */
1587pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1588 struct pid_namespace *ns);
1589
1590static inline pid_t task_pid_nr(struct task_struct *tsk)
1591{
1592 return tsk->pid;
1593}
1594
1595static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1596 struct pid_namespace *ns)
1597{
1598 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1599}
1600
1601static inline pid_t task_pid_vnr(struct task_struct *tsk)
1602{
1603 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1604}
1605
1606
1607static inline pid_t task_tgid_nr(struct task_struct *tsk)
1608{
1609 return tsk->tgid;
1610}
1611
1612pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1613
1614static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1615{
1616 return pid_vnr(task_tgid(tsk));
1617}
1618
1619
1620static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1621 struct pid_namespace *ns)
1622{
1623 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1624}
1625
1626static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1627{
1628 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1629}
1630
1631
1632static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1633 struct pid_namespace *ns)
1634{
1635 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1636}
1637
1638static inline pid_t task_session_vnr(struct task_struct *tsk)
1639{
1640 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1641}
1642
1643/* obsolete, do not use */
1644static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1645{
1646 return task_pgrp_nr_ns(tsk, &init_pid_ns);
1647}
1648
1649/**
1650 * pid_alive - check that a task structure is not stale
1651 * @p: Task structure to be checked.
1652 *
1653 * Test if a process is not yet dead (at most zombie state)
1654 * If pid_alive fails, then pointers within the task structure
1655 * can be stale and must not be dereferenced.
1656 */
1657static inline int pid_alive(struct task_struct *p)
1658{
1659 return p->pids[PIDTYPE_PID].pid != NULL;
1660}
1661
1662/**
1663 * is_global_init - check if a task structure is init
1664 * @tsk: Task structure to be checked.
1665 *
1666 * Check if a task structure is the first user space task the kernel created.
1667 */
1668static inline int is_global_init(struct task_struct *tsk)
1669{
1670 return tsk->pid == 1;
1671}
1672
1673/*
1674 * is_container_init:
1675 * check whether in the task is init in its own pid namespace.
1676 */
1677extern int is_container_init(struct task_struct *tsk);
1678
1679extern struct pid *cad_pid;
1680
1681extern void free_task(struct task_struct *tsk);
1682#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1683
1684extern void __put_task_struct(struct task_struct *t);
1685
1686static inline void put_task_struct(struct task_struct *t)
1687{
1688 if (atomic_dec_and_test(&t->usage))
1689 __put_task_struct(t);
1690}
1691
1692extern void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1693extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1694
1695/*
1696 * Per process flags
1697 */
1698#define PF_KSOFTIRQD 0x00000001 /* I am ksoftirqd */
1699#define PF_STARTING 0x00000002 /* being created */
1700#define PF_EXITING 0x00000004 /* getting shut down */
1701#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */
1702#define PF_VCPU 0x00000010 /* I'm a virtual CPU */
1703#define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */
1704#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
1705#define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */
1706#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
1707#define PF_DUMPCORE 0x00000200 /* dumped core */
1708#define PF_SIGNALED 0x00000400 /* killed by a signal */
1709#define PF_MEMALLOC 0x00000800 /* Allocating memory */
1710#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
1711#define PF_FREEZING 0x00004000 /* freeze in progress. do not account to load */
1712#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
1713#define PF_FROZEN 0x00010000 /* frozen for system suspend */
1714#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
1715#define PF_KSWAPD 0x00040000 /* I am kswapd */
1716#define PF_OOM_ORIGIN 0x00080000 /* Allocating much memory to others */
1717#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
1718#define PF_KTHREAD 0x00200000 /* I am a kernel thread */
1719#define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */
1720#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1721#define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */
1722#define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */
1723#define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpu */
1724#define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
1725#define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */
1726#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
1727#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezeable */
1728#define PF_FREEZER_NOSIG 0x80000000 /* Freezer won't send signals to it */
1729
1730/*
1731 * Only the _current_ task can read/write to tsk->flags, but other
1732 * tasks can access tsk->flags in readonly mode for example
1733 * with tsk_used_math (like during threaded core dumping).
1734 * There is however an exception to this rule during ptrace
1735 * or during fork: the ptracer task is allowed to write to the
1736 * child->flags of its traced child (same goes for fork, the parent
1737 * can write to the child->flags), because we're guaranteed the
1738 * child is not running and in turn not changing child->flags
1739 * at the same time the parent does it.
1740 */
1741#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1742#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1743#define clear_used_math() clear_stopped_child_used_math(current)
1744#define set_used_math() set_stopped_child_used_math(current)
1745#define conditional_stopped_child_used_math(condition, child) \
1746 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1747#define conditional_used_math(condition) \
1748 conditional_stopped_child_used_math(condition, current)
1749#define copy_to_stopped_child_used_math(child) \
1750 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1751/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1752#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1753#define used_math() tsk_used_math(current)
1754
1755#ifdef CONFIG_PREEMPT_RCU
1756
1757#define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */
1758#define RCU_READ_UNLOCK_NEED_QS (1 << 1) /* RCU core needs CPU response. */
1759
1760static inline void rcu_copy_process(struct task_struct *p)
1761{
1762 p->rcu_read_lock_nesting = 0;
1763 p->rcu_read_unlock_special = 0;
1764#ifdef CONFIG_TREE_PREEMPT_RCU
1765 p->rcu_blocked_node = NULL;
1766#endif
1767 INIT_LIST_HEAD(&p->rcu_node_entry);
1768}
1769
1770#else
1771
1772static inline void rcu_copy_process(struct task_struct *p)
1773{
1774}
1775
1776#endif
1777
1778#ifdef CONFIG_SMP
1779extern int set_cpus_allowed_ptr(struct task_struct *p,
1780 const struct cpumask *new_mask);
1781#else
1782static inline int set_cpus_allowed_ptr(struct task_struct *p,
1783 const struct cpumask *new_mask)
1784{
1785 if (!cpumask_test_cpu(0, new_mask))
1786 return -EINVAL;
1787 return 0;
1788}
1789#endif
1790
1791#ifndef CONFIG_CPUMASK_OFFSTACK
1792static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1793{
1794 return set_cpus_allowed_ptr(p, &new_mask);
1795}
1796#endif
1797
1798/*
1799 * Do not use outside of architecture code which knows its limitations.
1800 *
1801 * sched_clock() has no promise of monotonicity or bounded drift between
1802 * CPUs, use (which you should not) requires disabling IRQs.
1803 *
1804 * Please use one of the three interfaces below.
1805 */
1806extern unsigned long long notrace sched_clock(void);
1807/*
1808 * See the comment in kernel/sched_clock.c
1809 */
1810extern u64 cpu_clock(int cpu);
1811extern u64 local_clock(void);
1812extern u64 sched_clock_cpu(int cpu);
1813
1814
1815extern void sched_clock_init(void);
1816
1817#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1818static inline void sched_clock_tick(void)
1819{
1820}
1821
1822static inline void sched_clock_idle_sleep_event(void)
1823{
1824}
1825
1826static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
1827{
1828}
1829#else
1830/*
1831 * Architectures can set this to 1 if they have specified
1832 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
1833 * but then during bootup it turns out that sched_clock()
1834 * is reliable after all:
1835 */
1836extern int sched_clock_stable;
1837
1838extern void sched_clock_tick(void);
1839extern void sched_clock_idle_sleep_event(void);
1840extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1841#endif
1842
1843#ifdef CONFIG_IRQ_TIME_ACCOUNTING
1844/*
1845 * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
1846 * The reason for this explicit opt-in is not to have perf penalty with
1847 * slow sched_clocks.
1848 */
1849extern void enable_sched_clock_irqtime(void);
1850extern void disable_sched_clock_irqtime(void);
1851#else
1852static inline void enable_sched_clock_irqtime(void) {}
1853static inline void disable_sched_clock_irqtime(void) {}
1854#endif
1855
1856extern unsigned long long
1857task_sched_runtime(struct task_struct *task);
1858extern unsigned long long thread_group_sched_runtime(struct task_struct *task);
1859
1860/* sched_exec is called by processes performing an exec */
1861#ifdef CONFIG_SMP
1862extern void sched_exec(void);
1863#else
1864#define sched_exec() {}
1865#endif
1866
1867extern void sched_clock_idle_sleep_event(void);
1868extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1869
1870#ifdef CONFIG_HOTPLUG_CPU
1871extern void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p);
1872extern void idle_task_exit(void);
1873#else
1874static inline void idle_task_exit(void) {}
1875#endif
1876
1877extern void sched_idle_next(void);
1878
1879#if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1880extern void wake_up_idle_cpu(int cpu);
1881#else
1882static inline void wake_up_idle_cpu(int cpu) { }
1883#endif
1884
1885extern unsigned int sysctl_sched_latency;
1886extern unsigned int sysctl_sched_min_granularity;
1887extern unsigned int sysctl_sched_wakeup_granularity;
1888extern unsigned int sysctl_sched_shares_ratelimit;
1889extern unsigned int sysctl_sched_shares_thresh;
1890extern unsigned int sysctl_sched_child_runs_first;
1891
1892enum sched_tunable_scaling {
1893 SCHED_TUNABLESCALING_NONE,
1894 SCHED_TUNABLESCALING_LOG,
1895 SCHED_TUNABLESCALING_LINEAR,
1896 SCHED_TUNABLESCALING_END,
1897};
1898extern enum sched_tunable_scaling sysctl_sched_tunable_scaling;
1899
1900#ifdef CONFIG_SCHED_DEBUG
1901extern unsigned int sysctl_sched_migration_cost;
1902extern unsigned int sysctl_sched_nr_migrate;
1903extern unsigned int sysctl_sched_time_avg;
1904extern unsigned int sysctl_timer_migration;
1905
1906int sched_proc_update_handler(struct ctl_table *table, int write,
1907 void __user *buffer, size_t *length,
1908 loff_t *ppos);
1909#endif
1910#ifdef CONFIG_SCHED_DEBUG
1911static inline unsigned int get_sysctl_timer_migration(void)
1912{
1913 return sysctl_timer_migration;
1914}
1915#else
1916static inline unsigned int get_sysctl_timer_migration(void)
1917{
1918 return 1;
1919}
1920#endif
1921extern unsigned int sysctl_sched_rt_period;
1922extern int sysctl_sched_rt_runtime;
1923
1924int sched_rt_handler(struct ctl_table *table, int write,
1925 void __user *buffer, size_t *lenp,
1926 loff_t *ppos);
1927
1928extern unsigned int sysctl_sched_compat_yield;
1929
1930#ifdef CONFIG_RT_MUTEXES
1931extern int rt_mutex_getprio(struct task_struct *p);
1932extern void rt_mutex_setprio(struct task_struct *p, int prio);
1933extern void rt_mutex_adjust_pi(struct task_struct *p);
1934#else
1935static inline int rt_mutex_getprio(struct task_struct *p)
1936{
1937 return p->normal_prio;
1938}
1939# define rt_mutex_adjust_pi(p) do { } while (0)
1940#endif
1941
1942extern void set_user_nice(struct task_struct *p, long nice);
1943extern int task_prio(const struct task_struct *p);
1944extern int task_nice(const struct task_struct *p);
1945extern int can_nice(const struct task_struct *p, const int nice);
1946extern int task_curr(const struct task_struct *p);
1947extern int idle_cpu(int cpu);
1948extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1949extern int sched_setscheduler_nocheck(struct task_struct *, int,
1950 struct sched_param *);
1951extern struct task_struct *idle_task(int cpu);
1952extern struct task_struct *curr_task(int cpu);
1953extern void set_curr_task(int cpu, struct task_struct *p);
1954
1955void yield(void);
1956
1957/*
1958 * The default (Linux) execution domain.
1959 */
1960extern struct exec_domain default_exec_domain;
1961
1962union thread_union {
1963 struct thread_info thread_info;
1964 unsigned long stack[THREAD_SIZE/sizeof(long)];
1965};
1966
1967#ifndef __HAVE_ARCH_KSTACK_END
1968static inline int kstack_end(void *addr)
1969{
1970 /* Reliable end of stack detection:
1971 * Some APM bios versions misalign the stack
1972 */
1973 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1974}
1975#endif
1976
1977extern union thread_union init_thread_union;
1978extern struct task_struct init_task;
1979
1980extern struct mm_struct init_mm;
1981
1982extern struct pid_namespace init_pid_ns;
1983
1984/*
1985 * find a task by one of its numerical ids
1986 *
1987 * find_task_by_pid_ns():
1988 * finds a task by its pid in the specified namespace
1989 * find_task_by_vpid():
1990 * finds a task by its virtual pid
1991 *
1992 * see also find_vpid() etc in include/linux/pid.h
1993 */
1994
1995extern struct task_struct *find_task_by_vpid(pid_t nr);
1996extern struct task_struct *find_task_by_pid_ns(pid_t nr,
1997 struct pid_namespace *ns);
1998
1999extern void __set_special_pids(struct pid *pid);
2000
2001/* per-UID process charging. */
2002extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
2003static inline struct user_struct *get_uid(struct user_struct *u)
2004{
2005 atomic_inc(&u->__count);
2006 return u;
2007}
2008extern void free_uid(struct user_struct *);
2009extern void release_uids(struct user_namespace *ns);
2010
2011#include <asm/current.h>
2012
2013extern void do_timer(unsigned long ticks);
2014
2015extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2016extern int wake_up_process(struct task_struct *tsk);
2017extern void wake_up_new_task(struct task_struct *tsk,
2018 unsigned long clone_flags);
2019#ifdef CONFIG_SMP
2020 extern void kick_process(struct task_struct *tsk);
2021#else
2022 static inline void kick_process(struct task_struct *tsk) { }
2023#endif
2024extern void sched_fork(struct task_struct *p, int clone_flags);
2025extern void sched_dead(struct task_struct *p);
2026
2027extern void proc_caches_init(void);
2028extern void flush_signals(struct task_struct *);
2029extern void __flush_signals(struct task_struct *);
2030extern void ignore_signals(struct task_struct *);
2031extern void flush_signal_handlers(struct task_struct *, int force_default);
2032extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2033
2034static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
2035{
2036 unsigned long flags;
2037 int ret;
2038
2039 spin_lock_irqsave(&tsk->sighand->siglock, flags);
2040 ret = dequeue_signal(tsk, mask, info);
2041 spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
2042
2043 return ret;
2044}
2045
2046extern void block_all_signals(int (*notifier)(void *priv), void *priv,
2047 sigset_t *mask);
2048extern void unblock_all_signals(void);
2049extern void release_task(struct task_struct * p);
2050extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2051extern int force_sigsegv(int, struct task_struct *);
2052extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2053extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2054extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2055extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
2056extern int kill_pgrp(struct pid *pid, int sig, int priv);
2057extern int kill_pid(struct pid *pid, int sig, int priv);
2058extern int kill_proc_info(int, struct siginfo *, pid_t);
2059extern int do_notify_parent(struct task_struct *, int);
2060extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2061extern void force_sig(int, struct task_struct *);
2062extern int send_sig(int, struct task_struct *, int);
2063extern int zap_other_threads(struct task_struct *p);
2064extern struct sigqueue *sigqueue_alloc(void);
2065extern void sigqueue_free(struct sigqueue *);
2066extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group);
2067extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2068extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
2069
2070static inline int kill_cad_pid(int sig, int priv)
2071{
2072 return kill_pid(cad_pid, sig, priv);
2073}
2074
2075/* These can be the second arg to send_sig_info/send_group_sig_info. */
2076#define SEND_SIG_NOINFO ((struct siginfo *) 0)
2077#define SEND_SIG_PRIV ((struct siginfo *) 1)
2078#define SEND_SIG_FORCED ((struct siginfo *) 2)
2079
2080/*
2081 * True if we are on the alternate signal stack.
2082 */
2083static inline int on_sig_stack(unsigned long sp)
2084{
2085#ifdef CONFIG_STACK_GROWSUP
2086 return sp >= current->sas_ss_sp &&
2087 sp - current->sas_ss_sp < current->sas_ss_size;
2088#else
2089 return sp > current->sas_ss_sp &&
2090 sp - current->sas_ss_sp <= current->sas_ss_size;
2091#endif
2092}
2093
2094static inline int sas_ss_flags(unsigned long sp)
2095{
2096 return (current->sas_ss_size == 0 ? SS_DISABLE
2097 : on_sig_stack(sp) ? SS_ONSTACK : 0);
2098}
2099
2100/*
2101 * Routines for handling mm_structs
2102 */
2103extern struct mm_struct * mm_alloc(void);
2104
2105/* mmdrop drops the mm and the page tables */
2106extern void __mmdrop(struct mm_struct *);
2107static inline void mmdrop(struct mm_struct * mm)
2108{
2109 if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2110 __mmdrop(mm);
2111}
2112
2113/* mmput gets rid of the mappings and all user-space */
2114extern void mmput(struct mm_struct *);
2115/* Grab a reference to a task's mm, if it is not already going away */
2116extern struct mm_struct *get_task_mm(struct task_struct *task);
2117/* Remove the current tasks stale references to the old mm_struct */
2118extern void mm_release(struct task_struct *, struct mm_struct *);
2119/* Allocate a new mm structure and copy contents from tsk->mm */
2120extern struct mm_struct *dup_mm(struct task_struct *tsk);
2121
2122extern int copy_thread(unsigned long, unsigned long, unsigned long,
2123 struct task_struct *, struct pt_regs *);
2124extern void flush_thread(void);
2125extern void exit_thread(void);
2126
2127extern void exit_files(struct task_struct *);
2128extern void __cleanup_sighand(struct sighand_struct *);
2129
2130extern void exit_itimers(struct signal_struct *);
2131extern void flush_itimer_signals(void);
2132
2133extern NORET_TYPE void do_group_exit(int);
2134
2135extern void daemonize(const char *, ...);
2136extern int allow_signal(int);
2137extern int disallow_signal(int);
2138
2139extern int do_execve(const char *,
2140 const char __user * const __user *,
2141 const char __user * const __user *, struct pt_regs *);
2142extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
2143struct task_struct *fork_idle(int);
2144
2145extern void set_task_comm(struct task_struct *tsk, char *from);
2146extern char *get_task_comm(char *to, struct task_struct *tsk);
2147
2148#ifdef CONFIG_SMP
2149extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2150#else
2151static inline unsigned long wait_task_inactive(struct task_struct *p,
2152 long match_state)
2153{
2154 return 1;
2155}
2156#endif
2157
2158#define next_task(p) \
2159 list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2160
2161#define for_each_process(p) \
2162 for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2163
2164extern bool current_is_single_threaded(void);
2165
2166/*
2167 * Careful: do_each_thread/while_each_thread is a double loop so
2168 * 'break' will not work as expected - use goto instead.
2169 */
2170#define do_each_thread(g, t) \
2171 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2172
2173#define while_each_thread(g, t) \
2174 while ((t = next_thread(t)) != g)
2175
2176static inline int get_nr_threads(struct task_struct *tsk)
2177{
2178 return tsk->signal->nr_threads;
2179}
2180
2181/* de_thread depends on thread_group_leader not being a pid based check */
2182#define thread_group_leader(p) (p == p->group_leader)
2183
2184/* Do to the insanities of de_thread it is possible for a process
2185 * to have the pid of the thread group leader without actually being
2186 * the thread group leader. For iteration through the pids in proc
2187 * all we care about is that we have a task with the appropriate
2188 * pid, we don't actually care if we have the right task.
2189 */
2190static inline int has_group_leader_pid(struct task_struct *p)
2191{
2192 return p->pid == p->tgid;
2193}
2194
2195static inline
2196int same_thread_group(struct task_struct *p1, struct task_struct *p2)
2197{
2198 return p1->tgid == p2->tgid;
2199}
2200
2201static inline struct task_struct *next_thread(const struct task_struct *p)
2202{
2203 return list_entry_rcu(p->thread_group.next,
2204 struct task_struct, thread_group);
2205}
2206
2207static inline int thread_group_empty(struct task_struct *p)
2208{
2209 return list_empty(&p->thread_group);
2210}
2211
2212#define delay_group_leader(p) \
2213 (thread_group_leader(p) && !thread_group_empty(p))
2214
2215static inline int task_detached(struct task_struct *p)
2216{
2217 return p->exit_signal == -1;
2218}
2219
2220/*
2221 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2222 * subscriptions and synchronises with wait4(). Also used in procfs. Also
2223 * pins the final release of task.io_context. Also protects ->cpuset and
2224 * ->cgroup.subsys[].
2225 *
2226 * Nests both inside and outside of read_lock(&tasklist_lock).
2227 * It must not be nested with write_lock_irq(&tasklist_lock),
2228 * neither inside nor outside.
2229 */
2230static inline void task_lock(struct task_struct *p)
2231{
2232 spin_lock(&p->alloc_lock);
2233}
2234
2235static inline void task_unlock(struct task_struct *p)
2236{
2237 spin_unlock(&p->alloc_lock);
2238}
2239
2240extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2241 unsigned long *flags);
2242
2243#define lock_task_sighand(tsk, flags) \
2244({ struct sighand_struct *__ss; \
2245 __cond_lock(&(tsk)->sighand->siglock, \
2246 (__ss = __lock_task_sighand(tsk, flags))); \
2247 __ss; \
2248}) \
2249
2250static inline void unlock_task_sighand(struct task_struct *tsk,
2251 unsigned long *flags)
2252{
2253 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2254}
2255
2256#ifndef __HAVE_THREAD_FUNCTIONS
2257
2258#define task_thread_info(task) ((struct thread_info *)(task)->stack)
2259#define task_stack_page(task) ((task)->stack)
2260
2261static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2262{
2263 *task_thread_info(p) = *task_thread_info(org);
2264 task_thread_info(p)->task = p;
2265}
2266
2267static inline unsigned long *end_of_stack(struct task_struct *p)
2268{
2269 return (unsigned long *)(task_thread_info(p) + 1);
2270}
2271
2272#endif
2273
2274static inline int object_is_on_stack(void *obj)
2275{
2276 void *stack = task_stack_page(current);
2277
2278 return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2279}
2280
2281extern void thread_info_cache_init(void);
2282
2283#ifdef CONFIG_DEBUG_STACK_USAGE
2284static inline unsigned long stack_not_used(struct task_struct *p)
2285{
2286 unsigned long *n = end_of_stack(p);
2287
2288 do { /* Skip over canary */
2289 n++;
2290 } while (!*n);
2291
2292 return (unsigned long)n - (unsigned long)end_of_stack(p);
2293}
2294#endif
2295
2296/* set thread flags in other task's structures
2297 * - see asm/thread_info.h for TIF_xxxx flags available
2298 */
2299static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2300{
2301 set_ti_thread_flag(task_thread_info(tsk), flag);
2302}
2303
2304static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2305{
2306 clear_ti_thread_flag(task_thread_info(tsk), flag);
2307}
2308
2309static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2310{
2311 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2312}
2313
2314static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2315{
2316 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2317}
2318
2319static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2320{
2321 return test_ti_thread_flag(task_thread_info(tsk), flag);
2322}
2323
2324static inline void set_tsk_need_resched(struct task_struct *tsk)
2325{
2326 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2327}
2328
2329static inline void clear_tsk_need_resched(struct task_struct *tsk)
2330{
2331 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2332}
2333
2334static inline int test_tsk_need_resched(struct task_struct *tsk)
2335{
2336 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2337}
2338
2339static inline int restart_syscall(void)
2340{
2341 set_tsk_thread_flag(current, TIF_SIGPENDING);
2342 return -ERESTARTNOINTR;
2343}
2344
2345static inline int signal_pending(struct task_struct *p)
2346{
2347 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2348}
2349
2350static inline int __fatal_signal_pending(struct task_struct *p)
2351{
2352 return unlikely(sigismember(&p->pending.signal, SIGKILL));
2353}
2354
2355static inline int fatal_signal_pending(struct task_struct *p)
2356{
2357 return signal_pending(p) && __fatal_signal_pending(p);
2358}
2359
2360static inline int signal_pending_state(long state, struct task_struct *p)
2361{
2362 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2363 return 0;
2364 if (!signal_pending(p))
2365 return 0;
2366
2367 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2368}
2369
2370static inline int need_resched(void)
2371{
2372 return unlikely(test_thread_flag(TIF_NEED_RESCHED));
2373}
2374
2375/*
2376 * cond_resched() and cond_resched_lock(): latency reduction via
2377 * explicit rescheduling in places that are safe. The return
2378 * value indicates whether a reschedule was done in fact.
2379 * cond_resched_lock() will drop the spinlock before scheduling,
2380 * cond_resched_softirq() will enable bhs before scheduling.
2381 */
2382extern int _cond_resched(void);
2383
2384#define cond_resched() ({ \
2385 __might_sleep(__FILE__, __LINE__, 0); \
2386 _cond_resched(); \
2387})
2388
2389extern int __cond_resched_lock(spinlock_t *lock);
2390
2391#ifdef CONFIG_PREEMPT
2392#define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET
2393#else
2394#define PREEMPT_LOCK_OFFSET 0
2395#endif
2396
2397#define cond_resched_lock(lock) ({ \
2398 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \
2399 __cond_resched_lock(lock); \
2400})
2401
2402extern int __cond_resched_softirq(void);
2403
2404#define cond_resched_softirq() ({ \
2405 __might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \
2406 __cond_resched_softirq(); \
2407})
2408
2409/*
2410 * Does a critical section need to be broken due to another
2411 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2412 * but a general need for low latency)
2413 */
2414static inline int spin_needbreak(spinlock_t *lock)
2415{
2416#ifdef CONFIG_PREEMPT
2417 return spin_is_contended(lock);
2418#else
2419 return 0;
2420#endif
2421}
2422
2423/*
2424 * Thread group CPU time accounting.
2425 */
2426void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2427void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2428
2429static inline void thread_group_cputime_init(struct signal_struct *sig)
2430{
2431 spin_lock_init(&sig->cputimer.lock);
2432}
2433
2434/*
2435 * Reevaluate whether the task has signals pending delivery.
2436 * Wake the task if so.
2437 * This is required every time the blocked sigset_t changes.
2438 * callers must hold sighand->siglock.
2439 */
2440extern void recalc_sigpending_and_wake(struct task_struct *t);
2441extern void recalc_sigpending(void);
2442
2443extern void signal_wake_up(struct task_struct *t, int resume_stopped);
2444
2445/*
2446 * Wrappers for p->thread_info->cpu access. No-op on UP.
2447 */
2448#ifdef CONFIG_SMP
2449
2450static inline unsigned int task_cpu(const struct task_struct *p)
2451{
2452 return task_thread_info(p)->cpu;
2453}
2454
2455extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2456
2457#else
2458
2459static inline unsigned int task_cpu(const struct task_struct *p)
2460{
2461 return 0;
2462}
2463
2464static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2465{
2466}
2467
2468#endif /* CONFIG_SMP */
2469
2470extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2471extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2472
2473extern void normalize_rt_tasks(void);
2474
2475#ifdef CONFIG_CGROUP_SCHED
2476
2477extern struct task_group init_task_group;
2478
2479extern struct task_group *sched_create_group(struct task_group *parent);
2480extern void sched_destroy_group(struct task_group *tg);
2481extern void sched_move_task(struct task_struct *tsk);
2482#ifdef CONFIG_FAIR_GROUP_SCHED
2483extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2484extern unsigned long sched_group_shares(struct task_group *tg);
2485#endif
2486#ifdef CONFIG_RT_GROUP_SCHED
2487extern int sched_group_set_rt_runtime(struct task_group *tg,
2488 long rt_runtime_us);
2489extern long sched_group_rt_runtime(struct task_group *tg);
2490extern int sched_group_set_rt_period(struct task_group *tg,
2491 long rt_period_us);
2492extern long sched_group_rt_period(struct task_group *tg);
2493extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
2494#endif
2495#endif
2496
2497extern int task_can_switch_user(struct user_struct *up,
2498 struct task_struct *tsk);
2499
2500#ifdef CONFIG_TASK_XACCT
2501static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2502{
2503 tsk->ioac.rchar += amt;
2504}
2505
2506static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2507{
2508 tsk->ioac.wchar += amt;
2509}
2510
2511static inline void inc_syscr(struct task_struct *tsk)
2512{
2513 tsk->ioac.syscr++;
2514}
2515
2516static inline void inc_syscw(struct task_struct *tsk)
2517{
2518 tsk->ioac.syscw++;
2519}
2520#else
2521static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2522{
2523}
2524
2525static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2526{
2527}
2528
2529static inline void inc_syscr(struct task_struct *tsk)
2530{
2531}
2532
2533static inline void inc_syscw(struct task_struct *tsk)
2534{
2535}
2536#endif
2537
2538#ifndef TASK_SIZE_OF
2539#define TASK_SIZE_OF(tsk) TASK_SIZE
2540#endif
2541
2542/*
2543 * Call the function if the target task is executing on a CPU right now:
2544 */
2545extern void task_oncpu_function_call(struct task_struct *p,
2546 void (*func) (void *info), void *info);
2547
2548
2549#ifdef CONFIG_MM_OWNER
2550extern void mm_update_next_owner(struct mm_struct *mm);
2551extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2552#else
2553static inline void mm_update_next_owner(struct mm_struct *mm)
2554{
2555}
2556
2557static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2558{
2559}
2560#endif /* CONFIG_MM_OWNER */
2561
2562static inline unsigned long task_rlimit(const struct task_struct *tsk,
2563 unsigned int limit)
2564{
2565 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur);
2566}
2567
2568static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
2569 unsigned int limit)
2570{
2571 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max);
2572}
2573
2574static inline unsigned long rlimit(unsigned int limit)
2575{
2576 return task_rlimit(current, limit);
2577}
2578
2579static inline unsigned long rlimit_max(unsigned int limit)
2580{
2581 return task_rlimit_max(current, limit);
2582}
2583
2584#endif /* __KERNEL__ */
2585
2586#endif