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/*
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;
101struct fs_struct;
102struct bts_context;
103struct perf_event_context;
104
105/*
106 * List of flags we want to share for kernel threads,
107 * if only because they are not used by them anyway.
108 */
109#define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
110
111/*
112 * These are the constant used to fake the fixed-point load-average
113 * counting. Some notes:
114 * - 11 bit fractions expand to 22 bits by the multiplies: this gives
115 * a load-average precision of 10 bits integer + 11 bits fractional
116 * - if you want to count load-averages more often, you need more
117 * precision, or rounding will get you. With 2-second counting freq,
118 * the EXP_n values would be 1981, 2034 and 2043 if still using only
119 * 11 bit fractions.
120 */
121extern unsigned long avenrun[]; /* Load averages */
122extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
123
124#define FSHIFT 11 /* nr of bits of precision */
125#define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
126#define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */
127#define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
128#define EXP_5 2014 /* 1/exp(5sec/5min) */
129#define EXP_15 2037 /* 1/exp(5sec/15min) */
130
131#define CALC_LOAD(load,exp,n) \
132 load *= exp; \
133 load += n*(FIXED_1-exp); \
134 load >>= FSHIFT;
135
136extern unsigned long total_forks;
137extern int nr_threads;
138DECLARE_PER_CPU(unsigned long, process_counts);
139extern int nr_processes(void);
140extern unsigned long nr_running(void);
141extern unsigned long nr_uninterruptible(void);
142extern unsigned long nr_iowait(void);
143extern unsigned long nr_iowait_cpu(void);
144extern unsigned long this_cpu_load(void);
145
146
147extern void calc_global_load(void);
148extern u64 cpu_nr_migrations(int cpu);
149
150extern unsigned long get_parent_ip(unsigned long addr);
151
152struct seq_file;
153struct cfs_rq;
154struct task_group;
155#ifdef CONFIG_SCHED_DEBUG
156extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
157extern void proc_sched_set_task(struct task_struct *p);
158extern void
159print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
160#else
161static inline void
162proc_sched_show_task(struct task_struct *p, struct seq_file *m)
163{
164}
165static inline void proc_sched_set_task(struct task_struct *p)
166{
167}
168static inline void
169print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
170{
171}
172#endif
173
174extern unsigned long long time_sync_thresh;
175
176/*
177 * Task state bitmask. NOTE! These bits are also
178 * encoded in fs/proc/array.c: get_task_state().
179 *
180 * We have two separate sets of flags: task->state
181 * is about runnability, while task->exit_state are
182 * about the task exiting. Confusing, but this way
183 * modifying one set can't modify the other one by
184 * mistake.
185 */
186#define TASK_RUNNING 0
187#define TASK_INTERRUPTIBLE 1
188#define TASK_UNINTERRUPTIBLE 2
189#define __TASK_STOPPED 4
190#define __TASK_TRACED 8
191/* in tsk->exit_state */
192#define EXIT_ZOMBIE 16
193#define EXIT_DEAD 32
194/* in tsk->state again */
195#define TASK_DEAD 64
196#define TASK_WAKEKILL 128
197#define TASK_WAKING 256
198
199/* Convenience macros for the sake of set_task_state */
200#define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
201#define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
202#define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED)
203
204/* Convenience macros for the sake of wake_up */
205#define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
206#define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
207
208/* get_task_state() */
209#define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \
210 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
211 __TASK_TRACED)
212
213#define task_is_traced(task) ((task->state & __TASK_TRACED) != 0)
214#define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0)
215#define task_is_stopped_or_traced(task) \
216 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
217#define task_contributes_to_load(task) \
218 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
219 (task->flags & PF_FREEZING) == 0)
220
221#define __set_task_state(tsk, state_value) \
222 do { (tsk)->state = (state_value); } while (0)
223#define set_task_state(tsk, state_value) \
224 set_mb((tsk)->state, (state_value))
225
226/*
227 * set_current_state() includes a barrier so that the write of current->state
228 * is correctly serialised wrt the caller's subsequent test of whether to
229 * actually sleep:
230 *
231 * set_current_state(TASK_UNINTERRUPTIBLE);
232 * if (do_i_need_to_sleep())
233 * schedule();
234 *
235 * If the caller does not need such serialisation then use __set_current_state()
236 */
237#define __set_current_state(state_value) \
238 do { current->state = (state_value); } while (0)
239#define set_current_state(state_value) \
240 set_mb(current->state, (state_value))
241
242/* Task command name length */
243#define TASK_COMM_LEN 16
244
245#include <linux/spinlock.h>
246
247/*
248 * This serializes "schedule()" and also protects
249 * the run-queue from deletions/modifications (but
250 * _adding_ to the beginning of the run-queue has
251 * a separate lock).
252 */
253extern rwlock_t tasklist_lock;
254extern spinlock_t mmlist_lock;
255
256struct task_struct;
257
258extern void sched_init(void);
259extern void sched_init_smp(void);
260extern asmlinkage void schedule_tail(struct task_struct *prev);
261extern void init_idle(struct task_struct *idle, int cpu);
262extern void init_idle_bootup_task(struct task_struct *idle);
263
264extern int runqueue_is_locked(int cpu);
265extern void task_rq_unlock_wait(struct task_struct *p);
266
267extern cpumask_var_t nohz_cpu_mask;
268#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
269extern int select_nohz_load_balancer(int cpu);
270extern int get_nohz_load_balancer(void);
271#else
272static inline int select_nohz_load_balancer(int cpu)
273{
274 return 0;
275}
276#endif
277
278/*
279 * Only dump TASK_* tasks. (0 for all tasks)
280 */
281extern void show_state_filter(unsigned long state_filter);
282
283static inline void show_state(void)
284{
285 show_state_filter(0);
286}
287
288extern void show_regs(struct pt_regs *);
289
290/*
291 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
292 * task), SP is the stack pointer of the first frame that should be shown in the back
293 * trace (or NULL if the entire call-chain of the task should be shown).
294 */
295extern void show_stack(struct task_struct *task, unsigned long *sp);
296
297void io_schedule(void);
298long io_schedule_timeout(long timeout);
299
300extern void cpu_init (void);
301extern void trap_init(void);
302extern void update_process_times(int user);
303extern void scheduler_tick(void);
304
305extern void sched_show_task(struct task_struct *p);
306
307#ifdef CONFIG_DETECT_SOFTLOCKUP
308extern void softlockup_tick(void);
309extern void touch_softlockup_watchdog(void);
310extern void touch_all_softlockup_watchdogs(void);
311extern int proc_dosoftlockup_thresh(struct ctl_table *table, int write,
312 void __user *buffer,
313 size_t *lenp, loff_t *ppos);
314extern unsigned int softlockup_panic;
315extern int softlockup_thresh;
316#else
317static inline void softlockup_tick(void)
318{
319}
320static inline void touch_softlockup_watchdog(void)
321{
322}
323static inline void touch_all_softlockup_watchdogs(void)
324{
325}
326#endif
327
328#ifdef CONFIG_DETECT_HUNG_TASK
329extern unsigned int sysctl_hung_task_panic;
330extern unsigned long sysctl_hung_task_check_count;
331extern unsigned long sysctl_hung_task_timeout_secs;
332extern unsigned long sysctl_hung_task_warnings;
333extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
334 void __user *buffer,
335 size_t *lenp, loff_t *ppos);
336#endif
337
338/* Attach to any functions which should be ignored in wchan output. */
339#define __sched __attribute__((__section__(".sched.text")))
340
341/* Linker adds these: start and end of __sched functions */
342extern char __sched_text_start[], __sched_text_end[];
343
344/* Is this address in the __sched functions? */
345extern int in_sched_functions(unsigned long addr);
346
347#define MAX_SCHEDULE_TIMEOUT LONG_MAX
348extern signed long schedule_timeout(signed long timeout);
349extern signed long schedule_timeout_interruptible(signed long timeout);
350extern signed long schedule_timeout_killable(signed long timeout);
351extern signed long schedule_timeout_uninterruptible(signed long timeout);
352asmlinkage void __schedule(void);
353asmlinkage void schedule(void);
354extern int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner);
355
356struct nsproxy;
357struct user_namespace;
358
359/*
360 * Default maximum number of active map areas, this limits the number of vmas
361 * per mm struct. Users can overwrite this number by sysctl but there is a
362 * problem.
363 *
364 * When a program's coredump is generated as ELF format, a section is created
365 * per a vma. In ELF, the number of sections is represented in unsigned short.
366 * This means the number of sections should be smaller than 65535 at coredump.
367 * Because the kernel adds some informative sections to a image of program at
368 * generating coredump, we need some margin. The number of extra sections is
369 * 1-3 now and depends on arch. We use "5" as safe margin, here.
370 */
371#define MAPCOUNT_ELF_CORE_MARGIN (5)
372#define DEFAULT_MAX_MAP_COUNT (USHORT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
373
374extern int sysctl_max_map_count;
375
376#include <linux/aio.h>
377
378extern unsigned long
379arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
380 unsigned long, unsigned long);
381extern unsigned long
382arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
383 unsigned long len, unsigned long pgoff,
384 unsigned long flags);
385extern void arch_unmap_area(struct mm_struct *, unsigned long);
386extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
387
388#if USE_SPLIT_PTLOCKS
389/*
390 * The mm counters are not protected by its page_table_lock,
391 * so must be incremented atomically.
392 */
393#define set_mm_counter(mm, member, value) atomic_long_set(&(mm)->_##member, value)
394#define get_mm_counter(mm, member) ((unsigned long)atomic_long_read(&(mm)->_##member))
395#define add_mm_counter(mm, member, value) atomic_long_add(value, &(mm)->_##member)
396#define inc_mm_counter(mm, member) atomic_long_inc(&(mm)->_##member)
397#define dec_mm_counter(mm, member) atomic_long_dec(&(mm)->_##member)
398
399#else /* !USE_SPLIT_PTLOCKS */
400/*
401 * The mm counters are protected by its page_table_lock,
402 * so can be incremented directly.
403 */
404#define set_mm_counter(mm, member, value) (mm)->_##member = (value)
405#define get_mm_counter(mm, member) ((mm)->_##member)
406#define add_mm_counter(mm, member, value) (mm)->_##member += (value)
407#define inc_mm_counter(mm, member) (mm)->_##member++
408#define dec_mm_counter(mm, member) (mm)->_##member--
409
410#endif /* !USE_SPLIT_PTLOCKS */
411
412#define get_mm_rss(mm) \
413 (get_mm_counter(mm, file_rss) + get_mm_counter(mm, anon_rss))
414#define update_hiwater_rss(mm) do { \
415 unsigned long _rss = get_mm_rss(mm); \
416 if ((mm)->hiwater_rss < _rss) \
417 (mm)->hiwater_rss = _rss; \
418} while (0)
419#define update_hiwater_vm(mm) do { \
420 if ((mm)->hiwater_vm < (mm)->total_vm) \
421 (mm)->hiwater_vm = (mm)->total_vm; \
422} while (0)
423
424static inline unsigned long get_mm_hiwater_rss(struct mm_struct *mm)
425{
426 return max(mm->hiwater_rss, get_mm_rss(mm));
427}
428
429static inline void setmax_mm_hiwater_rss(unsigned long *maxrss,
430 struct mm_struct *mm)
431{
432 unsigned long hiwater_rss = get_mm_hiwater_rss(mm);
433
434 if (*maxrss < hiwater_rss)
435 *maxrss = hiwater_rss;
436}
437
438static inline unsigned long get_mm_hiwater_vm(struct mm_struct *mm)
439{
440 return max(mm->hiwater_vm, mm->total_vm);
441}
442
443extern void set_dumpable(struct mm_struct *mm, int value);
444extern int get_dumpable(struct mm_struct *mm);
445
446/* mm flags */
447/* dumpable bits */
448#define MMF_DUMPABLE 0 /* core dump is permitted */
449#define MMF_DUMP_SECURELY 1 /* core file is readable only by root */
450
451#define MMF_DUMPABLE_BITS 2
452#define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
453
454/* coredump filter bits */
455#define MMF_DUMP_ANON_PRIVATE 2
456#define MMF_DUMP_ANON_SHARED 3
457#define MMF_DUMP_MAPPED_PRIVATE 4
458#define MMF_DUMP_MAPPED_SHARED 5
459#define MMF_DUMP_ELF_HEADERS 6
460#define MMF_DUMP_HUGETLB_PRIVATE 7
461#define MMF_DUMP_HUGETLB_SHARED 8
462
463#define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS
464#define MMF_DUMP_FILTER_BITS 7
465#define MMF_DUMP_FILTER_MASK \
466 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
467#define MMF_DUMP_FILTER_DEFAULT \
468 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\
469 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
470
471#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
472# define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS)
473#else
474# define MMF_DUMP_MASK_DEFAULT_ELF 0
475#endif
476 /* leave room for more dump flags */
477#define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */
478
479#define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
480
481struct sighand_struct {
482 atomic_t count;
483 struct k_sigaction action[_NSIG];
484 spinlock_t siglock;
485 wait_queue_head_t signalfd_wqh;
486};
487
488struct pacct_struct {
489 int ac_flag;
490 long ac_exitcode;
491 unsigned long ac_mem;
492 cputime_t ac_utime, ac_stime;
493 unsigned long ac_minflt, ac_majflt;
494};
495
496struct cpu_itimer {
497 cputime_t expires;
498 cputime_t incr;
499 u32 error;
500 u32 incr_error;
501};
502
503/**
504 * struct task_cputime - collected CPU time counts
505 * @utime: time spent in user mode, in &cputime_t units
506 * @stime: time spent in kernel mode, in &cputime_t units
507 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds
508 *
509 * This structure groups together three kinds of CPU time that are
510 * tracked for threads and thread groups. Most things considering
511 * CPU time want to group these counts together and treat all three
512 * of them in parallel.
513 */
514struct task_cputime {
515 cputime_t utime;
516 cputime_t stime;
517 unsigned long long sum_exec_runtime;
518};
519/* Alternate field names when used to cache expirations. */
520#define prof_exp stime
521#define virt_exp utime
522#define sched_exp sum_exec_runtime
523
524#define INIT_CPUTIME \
525 (struct task_cputime) { \
526 .utime = cputime_zero, \
527 .stime = cputime_zero, \
528 .sum_exec_runtime = 0, \
529 }
530
531/*
532 * Disable preemption until the scheduler is running.
533 * Reset by start_kernel()->sched_init()->init_idle().
534 *
535 * We include PREEMPT_ACTIVE to avoid cond_resched() from working
536 * before the scheduler is active -- see should_resched().
537 */
538#define INIT_PREEMPT_COUNT (1 + PREEMPT_ACTIVE)
539
540/**
541 * struct thread_group_cputimer - thread group interval timer counts
542 * @cputime: thread group interval timers.
543 * @running: non-zero when there are timers running and
544 * @cputime receives updates.
545 * @lock: lock for fields in this struct.
546 *
547 * This structure contains the version of task_cputime, above, that is
548 * used for thread group CPU timer calculations.
549 */
550struct thread_group_cputimer {
551 struct task_cputime cputime;
552 int running;
553 spinlock_t lock;
554};
555
556/*
557 * NOTE! "signal_struct" does not have it's own
558 * locking, because a shared signal_struct always
559 * implies a shared sighand_struct, so locking
560 * sighand_struct is always a proper superset of
561 * the locking of signal_struct.
562 */
563struct signal_struct {
564 atomic_t count;
565 atomic_t live;
566
567 wait_queue_head_t wait_chldexit; /* for wait4() */
568
569 /* current thread group signal load-balancing target: */
570 struct task_struct *curr_target;
571
572 /* shared signal handling: */
573 struct sigpending shared_pending;
574
575 /* thread group exit support */
576 int group_exit_code;
577 /* overloaded:
578 * - notify group_exit_task when ->count is equal to notify_count
579 * - everyone except group_exit_task is stopped during signal delivery
580 * of fatal signals, group_exit_task processes the signal.
581 */
582 int notify_count;
583 struct task_struct *group_exit_task;
584
585 /* thread group stop support, overloads group_exit_code too */
586 int group_stop_count;
587 unsigned int flags; /* see SIGNAL_* flags below */
588
589 /* POSIX.1b Interval Timers */
590 struct list_head posix_timers;
591
592 /* ITIMER_REAL timer for the process */
593 struct hrtimer real_timer;
594 struct pid *leader_pid;
595 ktime_t it_real_incr;
596
597 /*
598 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
599 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
600 * values are defined to 0 and 1 respectively
601 */
602 struct cpu_itimer it[2];
603
604 /*
605 * Thread group totals for process CPU timers.
606 * See thread_group_cputimer(), et al, for details.
607 */
608 struct thread_group_cputimer cputimer;
609
610 /* Earliest-expiration cache. */
611 struct task_cputime cputime_expires;
612
613 struct list_head cpu_timers[3];
614
615 struct pid *tty_old_pgrp;
616
617 /* boolean value for session group leader */
618 int leader;
619
620 struct tty_struct *tty; /* NULL if no tty */
621
622 /*
623 * Cumulative resource counters for dead threads in the group,
624 * and for reaped dead child processes forked by this group.
625 * Live threads maintain their own counters and add to these
626 * in __exit_signal, except for the group leader.
627 */
628 cputime_t utime, stime, cutime, cstime;
629 cputime_t gtime;
630 cputime_t cgtime;
631 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
632 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
633 unsigned long inblock, oublock, cinblock, coublock;
634 unsigned long maxrss, cmaxrss;
635 struct task_io_accounting ioac;
636
637 /*
638 * Cumulative ns of schedule CPU time fo dead threads in the
639 * group, not including a zombie group leader, (This only differs
640 * from jiffies_to_ns(utime + stime) if sched_clock uses something
641 * other than jiffies.)
642 */
643 unsigned long long sum_sched_runtime;
644
645 /*
646 * We don't bother to synchronize most readers of this at all,
647 * because there is no reader checking a limit that actually needs
648 * to get both rlim_cur and rlim_max atomically, and either one
649 * alone is a single word that can safely be read normally.
650 * getrlimit/setrlimit use task_lock(current->group_leader) to
651 * protect this instead of the siglock, because they really
652 * have no need to disable irqs.
653 */
654 struct rlimit rlim[RLIM_NLIMITS];
655
656#ifdef CONFIG_BSD_PROCESS_ACCT
657 struct pacct_struct pacct; /* per-process accounting information */
658#endif
659#ifdef CONFIG_TASKSTATS
660 struct taskstats *stats;
661#endif
662#ifdef CONFIG_AUDIT
663 unsigned audit_tty;
664 struct tty_audit_buf *tty_audit_buf;
665#endif
666
667 int oom_adj; /* OOM kill score adjustment (bit shift) */
668};
669
670/* Context switch must be unlocked if interrupts are to be enabled */
671#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
672# define __ARCH_WANT_UNLOCKED_CTXSW
673#endif
674
675/*
676 * Bits in flags field of signal_struct.
677 */
678#define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */
679#define SIGNAL_STOP_DEQUEUED 0x00000002 /* stop signal dequeued */
680#define SIGNAL_STOP_CONTINUED 0x00000004 /* SIGCONT since WCONTINUED reap */
681#define SIGNAL_GROUP_EXIT 0x00000008 /* group exit in progress */
682/*
683 * Pending notifications to parent.
684 */
685#define SIGNAL_CLD_STOPPED 0x00000010
686#define SIGNAL_CLD_CONTINUED 0x00000020
687#define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
688
689#define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */
690
691/* If true, all threads except ->group_exit_task have pending SIGKILL */
692static inline int signal_group_exit(const struct signal_struct *sig)
693{
694 return (sig->flags & SIGNAL_GROUP_EXIT) ||
695 (sig->group_exit_task != NULL);
696}
697
698/*
699 * Some day this will be a full-fledged user tracking system..
700 */
701struct user_struct {
702 atomic_t __count; /* reference count */
703 atomic_t processes; /* How many processes does this user have? */
704 atomic_t files; /* How many open files does this user have? */
705 atomic_t sigpending; /* How many pending signals does this user have? */
706#ifdef CONFIG_INOTIFY_USER
707 atomic_t inotify_watches; /* How many inotify watches does this user have? */
708 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */
709#endif
710#ifdef CONFIG_EPOLL
711 atomic_t epoll_watches; /* The number of file descriptors currently watched */
712#endif
713#ifdef CONFIG_POSIX_MQUEUE
714 /* protected by mq_lock */
715 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
716#endif
717 unsigned long locked_shm; /* How many pages of mlocked shm ? */
718
719#ifdef CONFIG_KEYS
720 struct key *uid_keyring; /* UID specific keyring */
721 struct key *session_keyring; /* UID's default session keyring */
722#endif
723
724 /* Hash table maintenance information */
725 struct hlist_node uidhash_node;
726 uid_t uid;
727 struct user_namespace *user_ns;
728
729#ifdef CONFIG_USER_SCHED
730 struct task_group *tg;
731#ifdef CONFIG_SYSFS
732 struct kobject kobj;
733 struct delayed_work work;
734#endif
735#endif
736
737#ifdef CONFIG_PERF_EVENTS
738 atomic_long_t locked_vm;
739#endif
740};
741
742extern int uids_sysfs_init(void);
743
744extern struct user_struct *find_user(uid_t);
745
746extern struct user_struct root_user;
747#define INIT_USER (&root_user)
748
749
750struct backing_dev_info;
751struct reclaim_state;
752
753#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
754struct sched_info {
755 /* cumulative counters */
756 unsigned long pcount; /* # of times run on this cpu */
757 unsigned long long run_delay; /* time spent waiting on a runqueue */
758
759 /* timestamps */
760 unsigned long long last_arrival,/* when we last ran on a cpu */
761 last_queued; /* when we were last queued to run */
762#ifdef CONFIG_SCHEDSTATS
763 /* BKL stats */
764 unsigned int bkl_count;
765#endif
766};
767#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
768
769#ifdef CONFIG_TASK_DELAY_ACCT
770struct task_delay_info {
771 spinlock_t lock;
772 unsigned int flags; /* Private per-task flags */
773
774 /* For each stat XXX, add following, aligned appropriately
775 *
776 * struct timespec XXX_start, XXX_end;
777 * u64 XXX_delay;
778 * u32 XXX_count;
779 *
780 * Atomicity of updates to XXX_delay, XXX_count protected by
781 * single lock above (split into XXX_lock if contention is an issue).
782 */
783
784 /*
785 * XXX_count is incremented on every XXX operation, the delay
786 * associated with the operation is added to XXX_delay.
787 * XXX_delay contains the accumulated delay time in nanoseconds.
788 */
789 struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */
790 u64 blkio_delay; /* wait for sync block io completion */
791 u64 swapin_delay; /* wait for swapin block io completion */
792 u32 blkio_count; /* total count of the number of sync block */
793 /* io operations performed */
794 u32 swapin_count; /* total count of the number of swapin block */
795 /* io operations performed */
796
797 struct timespec freepages_start, freepages_end;
798 u64 freepages_delay; /* wait for memory reclaim */
799 u32 freepages_count; /* total count of memory reclaim */
800};
801#endif /* CONFIG_TASK_DELAY_ACCT */
802
803static inline int sched_info_on(void)
804{
805#ifdef CONFIG_SCHEDSTATS
806 return 1;
807#elif defined(CONFIG_TASK_DELAY_ACCT)
808 extern int delayacct_on;
809 return delayacct_on;
810#else
811 return 0;
812#endif
813}
814
815enum cpu_idle_type {
816 CPU_IDLE,
817 CPU_NOT_IDLE,
818 CPU_NEWLY_IDLE,
819 CPU_MAX_IDLE_TYPES
820};
821
822/*
823 * sched-domains (multiprocessor balancing) declarations:
824 */
825
826/*
827 * Increase resolution of nice-level calculations:
828 */
829#define SCHED_LOAD_SHIFT 10
830#define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT)
831
832#define SCHED_LOAD_SCALE_FUZZ SCHED_LOAD_SCALE
833
834#ifdef CONFIG_SMP
835#define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */
836#define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */
837#define SD_BALANCE_EXEC 0x0004 /* Balance on exec */
838#define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */
839#define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */
840#define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */
841#define SD_PREFER_LOCAL 0x0040 /* Prefer to keep tasks local to this domain */
842#define SD_SHARE_CPUPOWER 0x0080 /* Domain members share cpu power */
843#define SD_POWERSAVINGS_BALANCE 0x0100 /* Balance for power savings */
844#define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */
845#define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */
846
847#define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */
848
849enum powersavings_balance_level {
850 POWERSAVINGS_BALANCE_NONE = 0, /* No power saving load balance */
851 POWERSAVINGS_BALANCE_BASIC, /* Fill one thread/core/package
852 * first for long running threads
853 */
854 POWERSAVINGS_BALANCE_WAKEUP, /* Also bias task wakeups to semi-idle
855 * cpu package for power savings
856 */
857 MAX_POWERSAVINGS_BALANCE_LEVELS
858};
859
860extern int sched_mc_power_savings, sched_smt_power_savings;
861
862static inline int sd_balance_for_mc_power(void)
863{
864 if (sched_smt_power_savings)
865 return SD_POWERSAVINGS_BALANCE;
866
867 return SD_PREFER_SIBLING;
868}
869
870static inline int sd_balance_for_package_power(void)
871{
872 if (sched_mc_power_savings | sched_smt_power_savings)
873 return SD_POWERSAVINGS_BALANCE;
874
875 return SD_PREFER_SIBLING;
876}
877
878/*
879 * Optimise SD flags for power savings:
880 * SD_BALANCE_NEWIDLE helps agressive task consolidation and power savings.
881 * Keep default SD flags if sched_{smt,mc}_power_saving=0
882 */
883
884static inline int sd_power_saving_flags(void)
885{
886 if (sched_mc_power_savings | sched_smt_power_savings)
887 return SD_BALANCE_NEWIDLE;
888
889 return 0;
890}
891
892struct sched_group {
893 struct sched_group *next; /* Must be a circular list */
894
895 /*
896 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
897 * single CPU.
898 */
899 unsigned int cpu_power;
900
901 /*
902 * The CPUs this group covers.
903 *
904 * NOTE: this field is variable length. (Allocated dynamically
905 * by attaching extra space to the end of the structure,
906 * depending on how many CPUs the kernel has booted up with)
907 *
908 * It is also be embedded into static data structures at build
909 * time. (See 'struct static_sched_group' in kernel/sched.c)
910 */
911 unsigned long cpumask[0];
912};
913
914static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
915{
916 return to_cpumask(sg->cpumask);
917}
918
919enum sched_domain_level {
920 SD_LV_NONE = 0,
921 SD_LV_SIBLING,
922 SD_LV_MC,
923 SD_LV_CPU,
924 SD_LV_NODE,
925 SD_LV_ALLNODES,
926 SD_LV_MAX
927};
928
929struct sched_domain_attr {
930 int relax_domain_level;
931};
932
933#define SD_ATTR_INIT (struct sched_domain_attr) { \
934 .relax_domain_level = -1, \
935}
936
937struct sched_domain {
938 /* These fields must be setup */
939 struct sched_domain *parent; /* top domain must be null terminated */
940 struct sched_domain *child; /* bottom domain must be null terminated */
941 struct sched_group *groups; /* the balancing groups of the domain */
942 unsigned long min_interval; /* Minimum balance interval ms */
943 unsigned long max_interval; /* Maximum balance interval ms */
944 unsigned int busy_factor; /* less balancing by factor if busy */
945 unsigned int imbalance_pct; /* No balance until over watermark */
946 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */
947 unsigned int busy_idx;
948 unsigned int idle_idx;
949 unsigned int newidle_idx;
950 unsigned int wake_idx;
951 unsigned int forkexec_idx;
952 unsigned int smt_gain;
953 int flags; /* See SD_* */
954 enum sched_domain_level level;
955
956 /* Runtime fields. */
957 unsigned long last_balance; /* init to jiffies. units in jiffies */
958 unsigned int balance_interval; /* initialise to 1. units in ms. */
959 unsigned int nr_balance_failed; /* initialise to 0 */
960
961 u64 last_update;
962
963#ifdef CONFIG_SCHEDSTATS
964 /* load_balance() stats */
965 unsigned int lb_count[CPU_MAX_IDLE_TYPES];
966 unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
967 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
968 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
969 unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
970 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
971 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
972 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
973
974 /* Active load balancing */
975 unsigned int alb_count;
976 unsigned int alb_failed;
977 unsigned int alb_pushed;
978
979 /* SD_BALANCE_EXEC stats */
980 unsigned int sbe_count;
981 unsigned int sbe_balanced;
982 unsigned int sbe_pushed;
983
984 /* SD_BALANCE_FORK stats */
985 unsigned int sbf_count;
986 unsigned int sbf_balanced;
987 unsigned int sbf_pushed;
988
989 /* try_to_wake_up() stats */
990 unsigned int ttwu_wake_remote;
991 unsigned int ttwu_move_affine;
992 unsigned int ttwu_move_balance;
993#endif
994#ifdef CONFIG_SCHED_DEBUG
995 char *name;
996#endif
997
998 /*
999 * Span of all CPUs in this domain.
1000 *
1001 * NOTE: this field is variable length. (Allocated dynamically
1002 * by attaching extra space to the end of the structure,
1003 * depending on how many CPUs the kernel has booted up with)
1004 *
1005 * It is also be embedded into static data structures at build
1006 * time. (See 'struct static_sched_domain' in kernel/sched.c)
1007 */
1008 unsigned long span[0];
1009};
1010
1011static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
1012{
1013 return to_cpumask(sd->span);
1014}
1015
1016extern void partition_sched_domains(int ndoms_new, struct cpumask *doms_new,
1017 struct sched_domain_attr *dattr_new);
1018
1019/* Test a flag in parent sched domain */
1020static inline int test_sd_parent(struct sched_domain *sd, int flag)
1021{
1022 if (sd->parent && (sd->parent->flags & flag))
1023 return 1;
1024
1025 return 0;
1026}
1027
1028unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu);
1029unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu);
1030
1031#else /* CONFIG_SMP */
1032
1033struct sched_domain_attr;
1034
1035static inline void
1036partition_sched_domains(int ndoms_new, struct cpumask *doms_new,
1037 struct sched_domain_attr *dattr_new)
1038{
1039}
1040#endif /* !CONFIG_SMP */
1041
1042
1043struct io_context; /* See blkdev.h */
1044
1045
1046#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1047extern void prefetch_stack(struct task_struct *t);
1048#else
1049static inline void prefetch_stack(struct task_struct *t) { }
1050#endif
1051
1052struct audit_context; /* See audit.c */
1053struct mempolicy;
1054struct pipe_inode_info;
1055struct uts_namespace;
1056
1057struct rq;
1058struct sched_domain;
1059
1060/*
1061 * wake flags
1062 */
1063#define WF_SYNC 0x01 /* waker goes to sleep after wakup */
1064#define WF_FORK 0x02 /* child wakeup after fork */
1065
1066struct sched_class {
1067 const struct sched_class *next;
1068
1069 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup);
1070 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int sleep);
1071 void (*yield_task) (struct rq *rq);
1072
1073 void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
1074
1075 struct task_struct * (*pick_next_task) (struct rq *rq);
1076 void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1077
1078#ifdef CONFIG_SMP
1079 int (*select_task_rq)(struct task_struct *p, int sd_flag, int flags);
1080
1081 unsigned long (*load_balance) (struct rq *this_rq, int this_cpu,
1082 struct rq *busiest, unsigned long max_load_move,
1083 struct sched_domain *sd, enum cpu_idle_type idle,
1084 int *all_pinned, int *this_best_prio);
1085
1086 int (*move_one_task) (struct rq *this_rq, int this_cpu,
1087 struct rq *busiest, struct sched_domain *sd,
1088 enum cpu_idle_type idle);
1089 void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
1090 void (*post_schedule) (struct rq *this_rq);
1091 void (*task_wake_up) (struct rq *this_rq, struct task_struct *task);
1092
1093 void (*set_cpus_allowed)(struct task_struct *p,
1094 const struct cpumask *newmask);
1095
1096 void (*rq_online)(struct rq *rq);
1097 void (*rq_offline)(struct rq *rq);
1098#endif
1099
1100 void (*set_curr_task) (struct rq *rq);
1101 void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1102 void (*task_new) (struct rq *rq, struct task_struct *p);
1103
1104 void (*switched_from) (struct rq *this_rq, struct task_struct *task,
1105 int running);
1106 void (*switched_to) (struct rq *this_rq, struct task_struct *task,
1107 int running);
1108 void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1109 int oldprio, int running);
1110
1111 unsigned int (*get_rr_interval) (struct task_struct *task);
1112
1113#ifdef CONFIG_FAIR_GROUP_SCHED
1114 void (*moved_group) (struct task_struct *p);
1115#endif
1116};
1117
1118struct load_weight {
1119 unsigned long weight, inv_weight;
1120};
1121
1122/*
1123 * CFS stats for a schedulable entity (task, task-group etc)
1124 *
1125 * Current field usage histogram:
1126 *
1127 * 4 se->block_start
1128 * 4 se->run_node
1129 * 4 se->sleep_start
1130 * 6 se->load.weight
1131 */
1132struct sched_entity {
1133 struct load_weight load; /* for load-balancing */
1134 struct rb_node run_node;
1135 struct list_head group_node;
1136 unsigned int on_rq;
1137
1138 u64 exec_start;
1139 u64 sum_exec_runtime;
1140 u64 vruntime;
1141 u64 prev_sum_exec_runtime;
1142
1143 u64 last_wakeup;
1144 u64 avg_overlap;
1145
1146 u64 nr_migrations;
1147
1148 u64 start_runtime;
1149 u64 avg_wakeup;
1150
1151 u64 avg_running;
1152
1153#ifdef CONFIG_SCHEDSTATS
1154 u64 wait_start;
1155 u64 wait_max;
1156 u64 wait_count;
1157 u64 wait_sum;
1158 u64 iowait_count;
1159 u64 iowait_sum;
1160
1161 u64 sleep_start;
1162 u64 sleep_max;
1163 s64 sum_sleep_runtime;
1164
1165 u64 block_start;
1166 u64 block_max;
1167 u64 exec_max;
1168 u64 slice_max;
1169
1170 u64 nr_migrations_cold;
1171 u64 nr_failed_migrations_affine;
1172 u64 nr_failed_migrations_running;
1173 u64 nr_failed_migrations_hot;
1174 u64 nr_forced_migrations;
1175 u64 nr_forced2_migrations;
1176
1177 u64 nr_wakeups;
1178 u64 nr_wakeups_sync;
1179 u64 nr_wakeups_migrate;
1180 u64 nr_wakeups_local;
1181 u64 nr_wakeups_remote;
1182 u64 nr_wakeups_affine;
1183 u64 nr_wakeups_affine_attempts;
1184 u64 nr_wakeups_passive;
1185 u64 nr_wakeups_idle;
1186#endif
1187
1188#ifdef CONFIG_FAIR_GROUP_SCHED
1189 struct sched_entity *parent;
1190 /* rq on which this entity is (to be) queued: */
1191 struct cfs_rq *cfs_rq;
1192 /* rq "owned" by this entity/group: */
1193 struct cfs_rq *my_q;
1194#endif
1195};
1196
1197struct sched_rt_entity {
1198 struct list_head run_list;
1199 unsigned long timeout;
1200 unsigned int time_slice;
1201 int nr_cpus_allowed;
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 rcu_node;
1214
1215struct task_struct {
1216 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
1217 void *stack;
1218 atomic_t usage;
1219 unsigned int flags; /* per process flags, defined below */
1220 unsigned int ptrace;
1221
1222 int lock_depth; /* BKL lock depth */
1223
1224#ifdef CONFIG_SMP
1225#ifdef __ARCH_WANT_UNLOCKED_CTXSW
1226 int oncpu;
1227#endif
1228#endif
1229
1230 int prio, static_prio, normal_prio;
1231 unsigned int rt_priority;
1232 const struct sched_class *sched_class;
1233 struct sched_entity se;
1234 struct sched_rt_entity rt;
1235
1236#ifdef CONFIG_PREEMPT_NOTIFIERS
1237 /* list of struct preempt_notifier: */
1238 struct hlist_head preempt_notifiers;
1239#endif
1240
1241 /*
1242 * fpu_counter contains the number of consecutive context switches
1243 * that the FPU is used. If this is over a threshold, the lazy fpu
1244 * saving becomes unlazy to save the trap. This is an unsigned char
1245 * so that after 256 times the counter wraps and the behavior turns
1246 * lazy again; this to deal with bursty apps that only use FPU for
1247 * a short time
1248 */
1249 unsigned char fpu_counter;
1250#ifdef CONFIG_BLK_DEV_IO_TRACE
1251 unsigned int btrace_seq;
1252#endif
1253
1254 unsigned int policy;
1255 cpumask_t cpus_allowed;
1256
1257#ifdef CONFIG_TREE_PREEMPT_RCU
1258 int rcu_read_lock_nesting;
1259 char rcu_read_unlock_special;
1260 struct rcu_node *rcu_blocked_node;
1261 struct list_head rcu_node_entry;
1262#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1263
1264#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1265 struct sched_info sched_info;
1266#endif
1267
1268 struct list_head tasks;
1269 struct plist_node pushable_tasks;
1270
1271 struct mm_struct *mm, *active_mm;
1272
1273/* task state */
1274 int exit_state;
1275 int exit_code, exit_signal;
1276 int pdeath_signal; /* The signal sent when the parent dies */
1277 /* ??? */
1278 unsigned int personality;
1279 unsigned did_exec:1;
1280 unsigned in_execve:1; /* Tell the LSMs that the process is doing an
1281 * execve */
1282 unsigned in_iowait:1;
1283
1284
1285 /* Revert to default priority/policy when forking */
1286 unsigned sched_reset_on_fork:1;
1287
1288 pid_t pid;
1289 pid_t tgid;
1290
1291#ifdef CONFIG_CC_STACKPROTECTOR
1292 /* Canary value for the -fstack-protector gcc feature */
1293 unsigned long stack_canary;
1294#endif
1295
1296 /*
1297 * pointers to (original) parent process, youngest child, younger sibling,
1298 * older sibling, respectively. (p->father can be replaced with
1299 * p->real_parent->pid)
1300 */
1301 struct task_struct *real_parent; /* real parent process */
1302 struct task_struct *parent; /* recipient of SIGCHLD, wait4() reports */
1303 /*
1304 * children/sibling forms the list of my natural children
1305 */
1306 struct list_head children; /* list of my children */
1307 struct list_head sibling; /* linkage in my parent's children list */
1308 struct task_struct *group_leader; /* threadgroup leader */
1309
1310 /*
1311 * ptraced is the list of tasks this task is using ptrace on.
1312 * This includes both natural children and PTRACE_ATTACH targets.
1313 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1314 */
1315 struct list_head ptraced;
1316 struct list_head ptrace_entry;
1317
1318 /*
1319 * This is the tracer handle for the ptrace BTS extension.
1320 * This field actually belongs to the ptracer task.
1321 */
1322 struct bts_context *bts;
1323
1324 /* PID/PID hash table linkage. */
1325 struct pid_link pids[PIDTYPE_MAX];
1326 struct list_head thread_group;
1327
1328 struct completion *vfork_done; /* for vfork() */
1329 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
1330 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
1331
1332 cputime_t utime, stime, utimescaled, stimescaled;
1333 cputime_t gtime;
1334 cputime_t prev_utime, prev_stime;
1335 unsigned long nvcsw, nivcsw; /* context switch counts */
1336 struct timespec start_time; /* monotonic time */
1337 struct timespec real_start_time; /* boot based time */
1338/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1339 unsigned long min_flt, maj_flt;
1340
1341 struct task_cputime cputime_expires;
1342 struct list_head cpu_timers[3];
1343
1344/* process credentials */
1345 const struct cred *real_cred; /* objective and real subjective task
1346 * credentials (COW) */
1347 const struct cred *cred; /* effective (overridable) subjective task
1348 * credentials (COW) */
1349 struct mutex cred_guard_mutex; /* guard against foreign influences on
1350 * credential calculations
1351 * (notably. ptrace) */
1352 struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */
1353
1354 char comm[TASK_COMM_LEN]; /* executable name excluding path
1355 - access with [gs]et_task_comm (which lock
1356 it with task_lock())
1357 - initialized normally by flush_old_exec */
1358/* file system info */
1359 int link_count, total_link_count;
1360#ifdef CONFIG_SYSVIPC
1361/* ipc stuff */
1362 struct sysv_sem sysvsem;
1363#endif
1364#ifdef CONFIG_DETECT_HUNG_TASK
1365/* hung task detection */
1366 unsigned long last_switch_count;
1367#endif
1368/* CPU-specific state of this task */
1369 struct thread_struct thread;
1370/* filesystem information */
1371 struct fs_struct *fs;
1372/* open file information */
1373 struct files_struct *files;
1374/* namespaces */
1375 struct nsproxy *nsproxy;
1376/* signal handlers */
1377 struct signal_struct *signal;
1378 struct sighand_struct *sighand;
1379
1380 sigset_t blocked, real_blocked;
1381 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
1382 struct sigpending pending;
1383
1384 unsigned long sas_ss_sp;
1385 size_t sas_ss_size;
1386 int (*notifier)(void *priv);
1387 void *notifier_data;
1388 sigset_t *notifier_mask;
1389 struct audit_context *audit_context;
1390#ifdef CONFIG_AUDITSYSCALL
1391 uid_t loginuid;
1392 unsigned int sessionid;
1393#endif
1394 seccomp_t seccomp;
1395
1396/* Thread group tracking */
1397 u32 parent_exec_id;
1398 u32 self_exec_id;
1399/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1400 * mempolicy */
1401 spinlock_t alloc_lock;
1402
1403#ifdef CONFIG_GENERIC_HARDIRQS
1404 /* IRQ handler threads */
1405 struct irqaction *irqaction;
1406#endif
1407
1408 /* Protection of the PI data structures: */
1409 spinlock_t pi_lock;
1410
1411#ifdef CONFIG_RT_MUTEXES
1412 /* PI waiters blocked on a rt_mutex held by this task */
1413 struct plist_head pi_waiters;
1414 /* Deadlock detection and priority inheritance handling */
1415 struct rt_mutex_waiter *pi_blocked_on;
1416#endif
1417
1418#ifdef CONFIG_DEBUG_MUTEXES
1419 /* mutex deadlock detection */
1420 struct mutex_waiter *blocked_on;
1421#endif
1422#ifdef CONFIG_TRACE_IRQFLAGS
1423 unsigned int irq_events;
1424 int hardirqs_enabled;
1425 unsigned long hardirq_enable_ip;
1426 unsigned int hardirq_enable_event;
1427 unsigned long hardirq_disable_ip;
1428 unsigned int hardirq_disable_event;
1429 int softirqs_enabled;
1430 unsigned long softirq_disable_ip;
1431 unsigned int softirq_disable_event;
1432 unsigned long softirq_enable_ip;
1433 unsigned int softirq_enable_event;
1434 int hardirq_context;
1435 int softirq_context;
1436#endif
1437#ifdef CONFIG_LOCKDEP
1438# define MAX_LOCK_DEPTH 48UL
1439 u64 curr_chain_key;
1440 int lockdep_depth;
1441 unsigned int lockdep_recursion;
1442 struct held_lock held_locks[MAX_LOCK_DEPTH];
1443 gfp_t lockdep_reclaim_gfp;
1444#endif
1445
1446/* journalling filesystem info */
1447 void *journal_info;
1448
1449/* stacked block device info */
1450 struct bio *bio_list, **bio_tail;
1451
1452/* VM state */
1453 struct reclaim_state *reclaim_state;
1454
1455 struct backing_dev_info *backing_dev_info;
1456
1457 struct io_context *io_context;
1458
1459 unsigned long ptrace_message;
1460 siginfo_t *last_siginfo; /* For ptrace use. */
1461 struct task_io_accounting ioac;
1462#if defined(CONFIG_TASK_XACCT)
1463 u64 acct_rss_mem1; /* accumulated rss usage */
1464 u64 acct_vm_mem1; /* accumulated virtual memory usage */
1465 cputime_t acct_timexpd; /* stime + utime since last update */
1466#endif
1467#ifdef CONFIG_CPUSETS
1468 nodemask_t mems_allowed; /* Protected by alloc_lock */
1469 int cpuset_mem_spread_rotor;
1470#endif
1471#ifdef CONFIG_CGROUPS
1472 /* Control Group info protected by css_set_lock */
1473 struct css_set *cgroups;
1474 /* cg_list protected by css_set_lock and tsk->alloc_lock */
1475 struct list_head cg_list;
1476#endif
1477#ifdef CONFIG_FUTEX
1478 struct robust_list_head __user *robust_list;
1479#ifdef CONFIG_COMPAT
1480 struct compat_robust_list_head __user *compat_robust_list;
1481#endif
1482 struct list_head pi_state_list;
1483 struct futex_pi_state *pi_state_cache;
1484#endif
1485#ifdef CONFIG_PERF_EVENTS
1486 struct perf_event_context *perf_event_ctxp;
1487 struct mutex perf_event_mutex;
1488 struct list_head perf_event_list;
1489#endif
1490#ifdef CONFIG_NUMA
1491 struct mempolicy *mempolicy; /* Protected by alloc_lock */
1492 short il_next;
1493#endif
1494 atomic_t fs_excl; /* holding fs exclusive resources */
1495 struct rcu_head rcu;
1496
1497 /*
1498 * cache last used pipe for splice
1499 */
1500 struct pipe_inode_info *splice_pipe;
1501#ifdef CONFIG_TASK_DELAY_ACCT
1502 struct task_delay_info *delays;
1503#endif
1504#ifdef CONFIG_FAULT_INJECTION
1505 int make_it_fail;
1506#endif
1507 struct prop_local_single dirties;
1508#ifdef CONFIG_LATENCYTOP
1509 int latency_record_count;
1510 struct latency_record latency_record[LT_SAVECOUNT];
1511#endif
1512 /*
1513 * time slack values; these are used to round up poll() and
1514 * select() etc timeout values. These are in nanoseconds.
1515 */
1516 unsigned long timer_slack_ns;
1517 unsigned long default_timer_slack_ns;
1518
1519 struct list_head *scm_work_list;
1520#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1521 /* Index of current stored adress in ret_stack */
1522 int curr_ret_stack;
1523 /* Stack of return addresses for return function tracing */
1524 struct ftrace_ret_stack *ret_stack;
1525 /* time stamp for last schedule */
1526 unsigned long long ftrace_timestamp;
1527 /*
1528 * Number of functions that haven't been traced
1529 * because of depth overrun.
1530 */
1531 atomic_t trace_overrun;
1532 /* Pause for the tracing */
1533 atomic_t tracing_graph_pause;
1534#endif
1535#ifdef CONFIG_TRACING
1536 /* state flags for use by tracers */
1537 unsigned long trace;
1538 /* bitmask of trace recursion */
1539 unsigned long trace_recursion;
1540#endif /* CONFIG_TRACING */
1541 unsigned long stack_start;
1542};
1543
1544/* Future-safe accessor for struct task_struct's cpus_allowed. */
1545#define tsk_cpumask(tsk) (&(tsk)->cpus_allowed)
1546
1547/*
1548 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1549 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1550 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1551 * values are inverted: lower p->prio value means higher priority.
1552 *
1553 * The MAX_USER_RT_PRIO value allows the actual maximum
1554 * RT priority to be separate from the value exported to
1555 * user-space. This allows kernel threads to set their
1556 * priority to a value higher than any user task. Note:
1557 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1558 */
1559
1560#define MAX_USER_RT_PRIO 100
1561#define MAX_RT_PRIO MAX_USER_RT_PRIO
1562
1563#define MAX_PRIO (MAX_RT_PRIO + 40)
1564#define DEFAULT_PRIO (MAX_RT_PRIO + 20)
1565
1566static inline int rt_prio(int prio)
1567{
1568 if (unlikely(prio < MAX_RT_PRIO))
1569 return 1;
1570 return 0;
1571}
1572
1573static inline int rt_task(struct task_struct *p)
1574{
1575 return rt_prio(p->prio);
1576}
1577
1578static inline struct pid *task_pid(struct task_struct *task)
1579{
1580 return task->pids[PIDTYPE_PID].pid;
1581}
1582
1583static inline struct pid *task_tgid(struct task_struct *task)
1584{
1585 return task->group_leader->pids[PIDTYPE_PID].pid;
1586}
1587
1588/*
1589 * Without tasklist or rcu lock it is not safe to dereference
1590 * the result of task_pgrp/task_session even if task == current,
1591 * we can race with another thread doing sys_setsid/sys_setpgid.
1592 */
1593static inline struct pid *task_pgrp(struct task_struct *task)
1594{
1595 return task->group_leader->pids[PIDTYPE_PGID].pid;
1596}
1597
1598static inline struct pid *task_session(struct task_struct *task)
1599{
1600 return task->group_leader->pids[PIDTYPE_SID].pid;
1601}
1602
1603struct pid_namespace;
1604
1605/*
1606 * the helpers to get the task's different pids as they are seen
1607 * from various namespaces
1608 *
1609 * task_xid_nr() : global id, i.e. the id seen from the init namespace;
1610 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of
1611 * current.
1612 * task_xid_nr_ns() : id seen from the ns specified;
1613 *
1614 * set_task_vxid() : assigns a virtual id to a task;
1615 *
1616 * see also pid_nr() etc in include/linux/pid.h
1617 */
1618pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1619 struct pid_namespace *ns);
1620
1621static inline pid_t task_pid_nr(struct task_struct *tsk)
1622{
1623 return tsk->pid;
1624}
1625
1626static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1627 struct pid_namespace *ns)
1628{
1629 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1630}
1631
1632static inline pid_t task_pid_vnr(struct task_struct *tsk)
1633{
1634 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1635}
1636
1637
1638static inline pid_t task_tgid_nr(struct task_struct *tsk)
1639{
1640 return tsk->tgid;
1641}
1642
1643pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1644
1645static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1646{
1647 return pid_vnr(task_tgid(tsk));
1648}
1649
1650
1651static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1652 struct pid_namespace *ns)
1653{
1654 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1655}
1656
1657static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1658{
1659 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1660}
1661
1662
1663static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1664 struct pid_namespace *ns)
1665{
1666 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1667}
1668
1669static inline pid_t task_session_vnr(struct task_struct *tsk)
1670{
1671 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1672}
1673
1674/* obsolete, do not use */
1675static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1676{
1677 return task_pgrp_nr_ns(tsk, &init_pid_ns);
1678}
1679
1680/**
1681 * pid_alive - check that a task structure is not stale
1682 * @p: Task structure to be checked.
1683 *
1684 * Test if a process is not yet dead (at most zombie state)
1685 * If pid_alive fails, then pointers within the task structure
1686 * can be stale and must not be dereferenced.
1687 */
1688static inline int pid_alive(struct task_struct *p)
1689{
1690 return p->pids[PIDTYPE_PID].pid != NULL;
1691}
1692
1693/**
1694 * is_global_init - check if a task structure is init
1695 * @tsk: Task structure to be checked.
1696 *
1697 * Check if a task structure is the first user space task the kernel created.
1698 */
1699static inline int is_global_init(struct task_struct *tsk)
1700{
1701 return tsk->pid == 1;
1702}
1703
1704/*
1705 * is_container_init:
1706 * check whether in the task is init in its own pid namespace.
1707 */
1708extern int is_container_init(struct task_struct *tsk);
1709
1710extern struct pid *cad_pid;
1711
1712extern void free_task(struct task_struct *tsk);
1713#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1714
1715extern void __put_task_struct(struct task_struct *t);
1716
1717static inline void put_task_struct(struct task_struct *t)
1718{
1719 if (atomic_dec_and_test(&t->usage))
1720 __put_task_struct(t);
1721}
1722
1723extern cputime_t task_utime(struct task_struct *p);
1724extern cputime_t task_stime(struct task_struct *p);
1725extern cputime_t task_gtime(struct task_struct *p);
1726
1727/*
1728 * Per process flags
1729 */
1730#define PF_ALIGNWARN 0x00000001 /* Print alignment warning msgs */
1731 /* Not implemented yet, only for 486*/
1732#define PF_STARTING 0x00000002 /* being created */
1733#define PF_EXITING 0x00000004 /* getting shut down */
1734#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */
1735#define PF_VCPU 0x00000010 /* I'm a virtual CPU */
1736#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
1737#define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */
1738#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
1739#define PF_DUMPCORE 0x00000200 /* dumped core */
1740#define PF_SIGNALED 0x00000400 /* killed by a signal */
1741#define PF_MEMALLOC 0x00000800 /* Allocating memory */
1742#define PF_FLUSHER 0x00001000 /* responsible for disk writeback */
1743#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
1744#define PF_FREEZING 0x00004000 /* freeze in progress. do not account to load */
1745#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
1746#define PF_FROZEN 0x00010000 /* frozen for system suspend */
1747#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
1748#define PF_KSWAPD 0x00040000 /* I am kswapd */
1749#define PF_OOM_ORIGIN 0x00080000 /* Allocating much memory to others */
1750#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
1751#define PF_KTHREAD 0x00200000 /* I am a kernel thread */
1752#define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */
1753#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1754#define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */
1755#define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */
1756#define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpu */
1757#define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
1758#define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */
1759#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
1760#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezeable */
1761#define PF_FREEZER_NOSIG 0x80000000 /* Freezer won't send signals to it */
1762
1763/*
1764 * Only the _current_ task can read/write to tsk->flags, but other
1765 * tasks can access tsk->flags in readonly mode for example
1766 * with tsk_used_math (like during threaded core dumping).
1767 * There is however an exception to this rule during ptrace
1768 * or during fork: the ptracer task is allowed to write to the
1769 * child->flags of its traced child (same goes for fork, the parent
1770 * can write to the child->flags), because we're guaranteed the
1771 * child is not running and in turn not changing child->flags
1772 * at the same time the parent does it.
1773 */
1774#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1775#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1776#define clear_used_math() clear_stopped_child_used_math(current)
1777#define set_used_math() set_stopped_child_used_math(current)
1778#define conditional_stopped_child_used_math(condition, child) \
1779 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1780#define conditional_used_math(condition) \
1781 conditional_stopped_child_used_math(condition, current)
1782#define copy_to_stopped_child_used_math(child) \
1783 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1784/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1785#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1786#define used_math() tsk_used_math(current)
1787
1788#ifdef CONFIG_TREE_PREEMPT_RCU
1789
1790#define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */
1791#define RCU_READ_UNLOCK_NEED_QS (1 << 1) /* RCU core needs CPU response. */
1792
1793static inline void rcu_copy_process(struct task_struct *p)
1794{
1795 p->rcu_read_lock_nesting = 0;
1796 p->rcu_read_unlock_special = 0;
1797 p->rcu_blocked_node = NULL;
1798 INIT_LIST_HEAD(&p->rcu_node_entry);
1799}
1800
1801#else
1802
1803static inline void rcu_copy_process(struct task_struct *p)
1804{
1805}
1806
1807#endif
1808
1809#ifdef CONFIG_SMP
1810extern int set_cpus_allowed_ptr(struct task_struct *p,
1811 const struct cpumask *new_mask);
1812#else
1813static inline int set_cpus_allowed_ptr(struct task_struct *p,
1814 const struct cpumask *new_mask)
1815{
1816 if (!cpumask_test_cpu(0, new_mask))
1817 return -EINVAL;
1818 return 0;
1819}
1820#endif
1821
1822#ifndef CONFIG_CPUMASK_OFFSTACK
1823static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1824{
1825 return set_cpus_allowed_ptr(p, &new_mask);
1826}
1827#endif
1828
1829/*
1830 * Architectures can set this to 1 if they have specified
1831 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
1832 * but then during bootup it turns out that sched_clock()
1833 * is reliable after all:
1834 */
1835#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1836extern int sched_clock_stable;
1837#endif
1838
1839extern unsigned long long sched_clock(void);
1840
1841extern void sched_clock_init(void);
1842extern u64 sched_clock_cpu(int cpu);
1843
1844#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1845static inline void sched_clock_tick(void)
1846{
1847}
1848
1849static inline void sched_clock_idle_sleep_event(void)
1850{
1851}
1852
1853static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
1854{
1855}
1856#else
1857extern void sched_clock_tick(void);
1858extern void sched_clock_idle_sleep_event(void);
1859extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1860#endif
1861
1862/*
1863 * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
1864 * clock constructed from sched_clock():
1865 */
1866extern unsigned long long cpu_clock(int cpu);
1867
1868extern unsigned long long
1869task_sched_runtime(struct task_struct *task);
1870extern unsigned long long thread_group_sched_runtime(struct task_struct *task);
1871
1872/* sched_exec is called by processes performing an exec */
1873#ifdef CONFIG_SMP
1874extern void sched_exec(void);
1875#else
1876#define sched_exec() {}
1877#endif
1878
1879extern void sched_clock_idle_sleep_event(void);
1880extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1881
1882#ifdef CONFIG_HOTPLUG_CPU
1883extern void idle_task_exit(void);
1884#else
1885static inline void idle_task_exit(void) {}
1886#endif
1887
1888extern void sched_idle_next(void);
1889
1890#if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1891extern void wake_up_idle_cpu(int cpu);
1892#else
1893static inline void wake_up_idle_cpu(int cpu) { }
1894#endif
1895
1896extern unsigned int sysctl_sched_latency;
1897extern unsigned int sysctl_sched_min_granularity;
1898extern unsigned int sysctl_sched_wakeup_granularity;
1899extern unsigned int sysctl_sched_shares_ratelimit;
1900extern unsigned int sysctl_sched_shares_thresh;
1901extern unsigned int sysctl_sched_child_runs_first;
1902#ifdef CONFIG_SCHED_DEBUG
1903extern unsigned int sysctl_sched_features;
1904extern unsigned int sysctl_sched_migration_cost;
1905extern unsigned int sysctl_sched_nr_migrate;
1906extern unsigned int sysctl_sched_time_avg;
1907extern unsigned int sysctl_timer_migration;
1908
1909int sched_nr_latency_handler(struct ctl_table *table, int write,
1910 void __user *buffer, size_t *length,
1911 loff_t *ppos);
1912#endif
1913#ifdef CONFIG_SCHED_DEBUG
1914static inline unsigned int get_sysctl_timer_migration(void)
1915{
1916 return sysctl_timer_migration;
1917}
1918#else
1919static inline unsigned int get_sysctl_timer_migration(void)
1920{
1921 return 1;
1922}
1923#endif
1924extern unsigned int sysctl_sched_rt_period;
1925extern int sysctl_sched_rt_runtime;
1926
1927int sched_rt_handler(struct ctl_table *table, int write,
1928 void __user *buffer, size_t *lenp,
1929 loff_t *ppos);
1930
1931extern unsigned int sysctl_sched_compat_yield;
1932
1933#ifdef CONFIG_RT_MUTEXES
1934extern int rt_mutex_getprio(struct task_struct *p);
1935extern void rt_mutex_setprio(struct task_struct *p, int prio);
1936extern void rt_mutex_adjust_pi(struct task_struct *p);
1937#else
1938static inline int rt_mutex_getprio(struct task_struct *p)
1939{
1940 return p->normal_prio;
1941}
1942# define rt_mutex_adjust_pi(p) do { } while (0)
1943#endif
1944
1945extern void set_user_nice(struct task_struct *p, long nice);
1946extern int task_prio(const struct task_struct *p);
1947extern int task_nice(const struct task_struct *p);
1948extern int can_nice(const struct task_struct *p, const int nice);
1949extern int task_curr(const struct task_struct *p);
1950extern int idle_cpu(int cpu);
1951extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1952extern int sched_setscheduler_nocheck(struct task_struct *, int,
1953 struct sched_param *);
1954extern struct task_struct *idle_task(int cpu);
1955extern struct task_struct *curr_task(int cpu);
1956extern void set_curr_task(int cpu, struct task_struct *p);
1957
1958void yield(void);
1959
1960/*
1961 * The default (Linux) execution domain.
1962 */
1963extern struct exec_domain default_exec_domain;
1964
1965union thread_union {
1966 struct thread_info thread_info;
1967 unsigned long stack[THREAD_SIZE/sizeof(long)];
1968};
1969
1970#ifndef __HAVE_ARCH_KSTACK_END
1971static inline int kstack_end(void *addr)
1972{
1973 /* Reliable end of stack detection:
1974 * Some APM bios versions misalign the stack
1975 */
1976 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1977}
1978#endif
1979
1980extern union thread_union init_thread_union;
1981extern struct task_struct init_task;
1982
1983extern struct mm_struct init_mm;
1984
1985extern struct pid_namespace init_pid_ns;
1986
1987/*
1988 * find a task by one of its numerical ids
1989 *
1990 * find_task_by_pid_ns():
1991 * finds a task by its pid in the specified namespace
1992 * find_task_by_vpid():
1993 * finds a task by its virtual pid
1994 *
1995 * see also find_vpid() etc in include/linux/pid.h
1996 */
1997
1998extern struct task_struct *find_task_by_vpid(pid_t nr);
1999extern struct task_struct *find_task_by_pid_ns(pid_t nr,
2000 struct pid_namespace *ns);
2001
2002extern void __set_special_pids(struct pid *pid);
2003
2004/* per-UID process charging. */
2005extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
2006static inline struct user_struct *get_uid(struct user_struct *u)
2007{
2008 atomic_inc(&u->__count);
2009 return u;
2010}
2011extern void free_uid(struct user_struct *);
2012extern void release_uids(struct user_namespace *ns);
2013
2014#include <asm/current.h>
2015
2016extern void do_timer(unsigned long ticks);
2017
2018extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2019extern int wake_up_process(struct task_struct *tsk);
2020extern void wake_up_new_task(struct task_struct *tsk,
2021 unsigned long clone_flags);
2022#ifdef CONFIG_SMP
2023 extern void kick_process(struct task_struct *tsk);
2024#else
2025 static inline void kick_process(struct task_struct *tsk) { }
2026#endif
2027extern void sched_fork(struct task_struct *p, int clone_flags);
2028extern void sched_dead(struct task_struct *p);
2029
2030extern void proc_caches_init(void);
2031extern void flush_signals(struct task_struct *);
2032extern void __flush_signals(struct task_struct *);
2033extern void ignore_signals(struct task_struct *);
2034extern void flush_signal_handlers(struct task_struct *, int force_default);
2035extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2036
2037static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
2038{
2039 unsigned long flags;
2040 int ret;
2041
2042 spin_lock_irqsave(&tsk->sighand->siglock, flags);
2043 ret = dequeue_signal(tsk, mask, info);
2044 spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
2045
2046 return ret;
2047}
2048
2049extern void block_all_signals(int (*notifier)(void *priv), void *priv,
2050 sigset_t *mask);
2051extern void unblock_all_signals(void);
2052extern void release_task(struct task_struct * p);
2053extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2054extern int force_sigsegv(int, struct task_struct *);
2055extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2056extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2057extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2058extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
2059extern int kill_pgrp(struct pid *pid, int sig, int priv);
2060extern int kill_pid(struct pid *pid, int sig, int priv);
2061extern int kill_proc_info(int, struct siginfo *, pid_t);
2062extern int do_notify_parent(struct task_struct *, int);
2063extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2064extern void force_sig(int, struct task_struct *);
2065extern void force_sig_specific(int, struct task_struct *);
2066extern int send_sig(int, struct task_struct *, int);
2067extern void zap_other_threads(struct task_struct *p);
2068extern struct sigqueue *sigqueue_alloc(void);
2069extern void sigqueue_free(struct sigqueue *);
2070extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group);
2071extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2072extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
2073
2074static inline int kill_cad_pid(int sig, int priv)
2075{
2076 return kill_pid(cad_pid, sig, priv);
2077}
2078
2079/* These can be the second arg to send_sig_info/send_group_sig_info. */
2080#define SEND_SIG_NOINFO ((struct siginfo *) 0)
2081#define SEND_SIG_PRIV ((struct siginfo *) 1)
2082#define SEND_SIG_FORCED ((struct siginfo *) 2)
2083
2084static inline int is_si_special(const struct siginfo *info)
2085{
2086 return info <= SEND_SIG_FORCED;
2087}
2088
2089/* True if we are on the alternate signal stack. */
2090
2091static inline int on_sig_stack(unsigned long sp)
2092{
2093 return (sp - current->sas_ss_sp < current->sas_ss_size);
2094}
2095
2096static inline int sas_ss_flags(unsigned long sp)
2097{
2098 return (current->sas_ss_size == 0 ? SS_DISABLE
2099 : on_sig_stack(sp) ? SS_ONSTACK : 0);
2100}
2101
2102/*
2103 * Routines for handling mm_structs
2104 */
2105extern struct mm_struct * mm_alloc(void);
2106
2107/* mmdrop drops the mm and the page tables */
2108extern void __mmdrop(struct mm_struct *);
2109static inline void mmdrop(struct mm_struct * mm)
2110{
2111 if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2112 __mmdrop(mm);
2113}
2114
2115/* mmput gets rid of the mappings and all user-space */
2116extern void mmput(struct mm_struct *);
2117/* Grab a reference to a task's mm, if it is not already going away */
2118extern struct mm_struct *get_task_mm(struct task_struct *task);
2119/* Remove the current tasks stale references to the old mm_struct */
2120extern void mm_release(struct task_struct *, struct mm_struct *);
2121/* Allocate a new mm structure and copy contents from tsk->mm */
2122extern struct mm_struct *dup_mm(struct task_struct *tsk);
2123
2124extern int copy_thread(unsigned long, unsigned long, unsigned long,
2125 struct task_struct *, struct pt_regs *);
2126extern void flush_thread(void);
2127extern void exit_thread(void);
2128
2129extern void exit_files(struct task_struct *);
2130extern void __cleanup_signal(struct signal_struct *);
2131extern void __cleanup_sighand(struct sighand_struct *);
2132
2133extern void exit_itimers(struct signal_struct *);
2134extern void flush_itimer_signals(void);
2135
2136extern NORET_TYPE void do_group_exit(int);
2137
2138extern void daemonize(const char *, ...);
2139extern int allow_signal(int);
2140extern int disallow_signal(int);
2141
2142extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
2143extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
2144struct task_struct *fork_idle(int);
2145
2146extern void set_task_comm(struct task_struct *tsk, char *from);
2147extern char *get_task_comm(char *to, struct task_struct *tsk);
2148
2149#ifdef CONFIG_SMP
2150extern void wait_task_context_switch(struct task_struct *p);
2151extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2152#else
2153static inline void wait_task_context_switch(struct task_struct *p) {}
2154static inline unsigned long wait_task_inactive(struct task_struct *p,
2155 long match_state)
2156{
2157 return 1;
2158}
2159#endif
2160
2161#define next_task(p) \
2162 list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2163
2164#define for_each_process(p) \
2165 for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2166
2167extern bool current_is_single_threaded(void);
2168
2169/*
2170 * Careful: do_each_thread/while_each_thread is a double loop so
2171 * 'break' will not work as expected - use goto instead.
2172 */
2173#define do_each_thread(g, t) \
2174 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2175
2176#define while_each_thread(g, t) \
2177 while ((t = next_thread(t)) != g)
2178
2179/* de_thread depends on thread_group_leader not being a pid based check */
2180#define thread_group_leader(p) (p == p->group_leader)
2181
2182/* Do to the insanities of de_thread it is possible for a process
2183 * to have the pid of the thread group leader without actually being
2184 * the thread group leader. For iteration through the pids in proc
2185 * all we care about is that we have a task with the appropriate
2186 * pid, we don't actually care if we have the right task.
2187 */
2188static inline int has_group_leader_pid(struct task_struct *p)
2189{
2190 return p->pid == p->tgid;
2191}
2192
2193static inline
2194int same_thread_group(struct task_struct *p1, struct task_struct *p2)
2195{
2196 return p1->tgid == p2->tgid;
2197}
2198
2199static inline struct task_struct *next_thread(const struct task_struct *p)
2200{
2201 return list_entry_rcu(p->thread_group.next,
2202 struct task_struct, thread_group);
2203}
2204
2205static inline int thread_group_empty(struct task_struct *p)
2206{
2207 return list_empty(&p->thread_group);
2208}
2209
2210#define delay_group_leader(p) \
2211 (thread_group_leader(p) && !thread_group_empty(p))
2212
2213static inline int task_detached(struct task_struct *p)
2214{
2215 return p->exit_signal == -1;
2216}
2217
2218/*
2219 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2220 * subscriptions and synchronises with wait4(). Also used in procfs. Also
2221 * pins the final release of task.io_context. Also protects ->cpuset and
2222 * ->cgroup.subsys[].
2223 *
2224 * Nests both inside and outside of read_lock(&tasklist_lock).
2225 * It must not be nested with write_lock_irq(&tasklist_lock),
2226 * neither inside nor outside.
2227 */
2228static inline void task_lock(struct task_struct *p)
2229{
2230 spin_lock(&p->alloc_lock);
2231}
2232
2233static inline void task_unlock(struct task_struct *p)
2234{
2235 spin_unlock(&p->alloc_lock);
2236}
2237
2238extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2239 unsigned long *flags);
2240
2241static inline void unlock_task_sighand(struct task_struct *tsk,
2242 unsigned long *flags)
2243{
2244 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2245}
2246
2247#ifndef __HAVE_THREAD_FUNCTIONS
2248
2249#define task_thread_info(task) ((struct thread_info *)(task)->stack)
2250#define task_stack_page(task) ((task)->stack)
2251
2252static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2253{
2254 *task_thread_info(p) = *task_thread_info(org);
2255 task_thread_info(p)->task = p;
2256}
2257
2258static inline unsigned long *end_of_stack(struct task_struct *p)
2259{
2260 return (unsigned long *)(task_thread_info(p) + 1);
2261}
2262
2263#endif
2264
2265static inline int object_is_on_stack(void *obj)
2266{
2267 void *stack = task_stack_page(current);
2268
2269 return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2270}
2271
2272extern void thread_info_cache_init(void);
2273
2274#ifdef CONFIG_DEBUG_STACK_USAGE
2275static inline unsigned long stack_not_used(struct task_struct *p)
2276{
2277 unsigned long *n = end_of_stack(p);
2278
2279 do { /* Skip over canary */
2280 n++;
2281 } while (!*n);
2282
2283 return (unsigned long)n - (unsigned long)end_of_stack(p);
2284}
2285#endif
2286
2287/* set thread flags in other task's structures
2288 * - see asm/thread_info.h for TIF_xxxx flags available
2289 */
2290static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2291{
2292 set_ti_thread_flag(task_thread_info(tsk), flag);
2293}
2294
2295static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2296{
2297 clear_ti_thread_flag(task_thread_info(tsk), flag);
2298}
2299
2300static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2301{
2302 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2303}
2304
2305static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2306{
2307 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2308}
2309
2310static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2311{
2312 return test_ti_thread_flag(task_thread_info(tsk), flag);
2313}
2314
2315static inline void set_tsk_need_resched(struct task_struct *tsk)
2316{
2317 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2318}
2319
2320static inline void clear_tsk_need_resched(struct task_struct *tsk)
2321{
2322 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2323}
2324
2325static inline int test_tsk_need_resched(struct task_struct *tsk)
2326{
2327 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2328}
2329
2330static inline int restart_syscall(void)
2331{
2332 set_tsk_thread_flag(current, TIF_SIGPENDING);
2333 return -ERESTARTNOINTR;
2334}
2335
2336static inline int signal_pending(struct task_struct *p)
2337{
2338 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2339}
2340
2341static inline int __fatal_signal_pending(struct task_struct *p)
2342{
2343 return unlikely(sigismember(&p->pending.signal, SIGKILL));
2344}
2345
2346static inline int fatal_signal_pending(struct task_struct *p)
2347{
2348 return signal_pending(p) && __fatal_signal_pending(p);
2349}
2350
2351static inline int signal_pending_state(long state, struct task_struct *p)
2352{
2353 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2354 return 0;
2355 if (!signal_pending(p))
2356 return 0;
2357
2358 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2359}
2360
2361static inline int need_resched(void)
2362{
2363 return unlikely(test_thread_flag(TIF_NEED_RESCHED));
2364}
2365
2366/*
2367 * cond_resched() and cond_resched_lock(): latency reduction via
2368 * explicit rescheduling in places that are safe. The return
2369 * value indicates whether a reschedule was done in fact.
2370 * cond_resched_lock() will drop the spinlock before scheduling,
2371 * cond_resched_softirq() will enable bhs before scheduling.
2372 */
2373extern int _cond_resched(void);
2374
2375#define cond_resched() ({ \
2376 __might_sleep(__FILE__, __LINE__, 0); \
2377 _cond_resched(); \
2378})
2379
2380extern int __cond_resched_lock(spinlock_t *lock);
2381
2382#ifdef CONFIG_PREEMPT
2383#define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET
2384#else
2385#define PREEMPT_LOCK_OFFSET 0
2386#endif
2387
2388#define cond_resched_lock(lock) ({ \
2389 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \
2390 __cond_resched_lock(lock); \
2391})
2392
2393extern int __cond_resched_softirq(void);
2394
2395#define cond_resched_softirq() ({ \
2396 __might_sleep(__FILE__, __LINE__, SOFTIRQ_OFFSET); \
2397 __cond_resched_softirq(); \
2398})
2399
2400/*
2401 * Does a critical section need to be broken due to another
2402 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2403 * but a general need for low latency)
2404 */
2405static inline int spin_needbreak(spinlock_t *lock)
2406{
2407#ifdef CONFIG_PREEMPT
2408 return spin_is_contended(lock);
2409#else
2410 return 0;
2411#endif
2412}
2413
2414/*
2415 * Thread group CPU time accounting.
2416 */
2417void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2418void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2419
2420static inline void thread_group_cputime_init(struct signal_struct *sig)
2421{
2422 sig->cputimer.cputime = INIT_CPUTIME;
2423 spin_lock_init(&sig->cputimer.lock);
2424 sig->cputimer.running = 0;
2425}
2426
2427static inline void thread_group_cputime_free(struct signal_struct *sig)
2428{
2429}
2430
2431/*
2432 * Reevaluate whether the task has signals pending delivery.
2433 * Wake the task if so.
2434 * This is required every time the blocked sigset_t changes.
2435 * callers must hold sighand->siglock.
2436 */
2437extern void recalc_sigpending_and_wake(struct task_struct *t);
2438extern void recalc_sigpending(void);
2439
2440extern void signal_wake_up(struct task_struct *t, int resume_stopped);
2441
2442/*
2443 * Wrappers for p->thread_info->cpu access. No-op on UP.
2444 */
2445#ifdef CONFIG_SMP
2446
2447static inline unsigned int task_cpu(const struct task_struct *p)
2448{
2449 return task_thread_info(p)->cpu;
2450}
2451
2452extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2453
2454#else
2455
2456static inline unsigned int task_cpu(const struct task_struct *p)
2457{
2458 return 0;
2459}
2460
2461static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2462{
2463}
2464
2465#endif /* CONFIG_SMP */
2466
2467extern void arch_pick_mmap_layout(struct mm_struct *mm);
2468
2469#ifdef CONFIG_TRACING
2470extern void
2471__trace_special(void *__tr, void *__data,
2472 unsigned long arg1, unsigned long arg2, unsigned long arg3);
2473#else
2474static inline void
2475__trace_special(void *__tr, void *__data,
2476 unsigned long arg1, unsigned long arg2, unsigned long arg3)
2477{
2478}
2479#endif
2480
2481extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2482extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2483
2484extern void normalize_rt_tasks(void);
2485
2486#ifdef CONFIG_GROUP_SCHED
2487
2488extern struct task_group init_task_group;
2489#ifdef CONFIG_USER_SCHED
2490extern struct task_group root_task_group;
2491extern void set_tg_uid(struct user_struct *user);
2492#endif
2493
2494extern struct task_group *sched_create_group(struct task_group *parent);
2495extern void sched_destroy_group(struct task_group *tg);
2496extern void sched_move_task(struct task_struct *tsk);
2497#ifdef CONFIG_FAIR_GROUP_SCHED
2498extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2499extern unsigned long sched_group_shares(struct task_group *tg);
2500#endif
2501#ifdef CONFIG_RT_GROUP_SCHED
2502extern int sched_group_set_rt_runtime(struct task_group *tg,
2503 long rt_runtime_us);
2504extern long sched_group_rt_runtime(struct task_group *tg);
2505extern int sched_group_set_rt_period(struct task_group *tg,
2506 long rt_period_us);
2507extern long sched_group_rt_period(struct task_group *tg);
2508extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
2509#endif
2510#endif
2511
2512extern int task_can_switch_user(struct user_struct *up,
2513 struct task_struct *tsk);
2514
2515#ifdef CONFIG_TASK_XACCT
2516static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2517{
2518 tsk->ioac.rchar += amt;
2519}
2520
2521static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2522{
2523 tsk->ioac.wchar += amt;
2524}
2525
2526static inline void inc_syscr(struct task_struct *tsk)
2527{
2528 tsk->ioac.syscr++;
2529}
2530
2531static inline void inc_syscw(struct task_struct *tsk)
2532{
2533 tsk->ioac.syscw++;
2534}
2535#else
2536static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2537{
2538}
2539
2540static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2541{
2542}
2543
2544static inline void inc_syscr(struct task_struct *tsk)
2545{
2546}
2547
2548static inline void inc_syscw(struct task_struct *tsk)
2549{
2550}
2551#endif
2552
2553#ifndef TASK_SIZE_OF
2554#define TASK_SIZE_OF(tsk) TASK_SIZE
2555#endif
2556
2557/*
2558 * Call the function if the target task is executing on a CPU right now:
2559 */
2560extern void task_oncpu_function_call(struct task_struct *p,
2561 void (*func) (void *info), void *info);
2562
2563
2564#ifdef CONFIG_MM_OWNER
2565extern void mm_update_next_owner(struct mm_struct *mm);
2566extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2567#else
2568static inline void mm_update_next_owner(struct mm_struct *mm)
2569{
2570}
2571
2572static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2573{
2574}
2575#endif /* CONFIG_MM_OWNER */
2576
2577#define TASK_STATE_TO_CHAR_STR "RSDTtZX"
2578
2579#endif /* __KERNEL__ */
2580
2581#endif