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/* 0x02000000 was previously the unused CLONE_STOPPED (Start in stopped state)
25 and is now available for re-use. */
26#define CLONE_NEWUTS 0x04000000 /* New utsname group? */
27#define CLONE_NEWIPC 0x08000000 /* New ipcs */
28#define CLONE_NEWUSER 0x10000000 /* New user namespace */
29#define CLONE_NEWPID 0x20000000 /* New pid namespace */
30#define CLONE_NEWNET 0x40000000 /* New network namespace */
31#define CLONE_IO 0x80000000 /* Clone io context */
32
33/*
34 * Scheduling policies
35 */
36#define SCHED_NORMAL 0
37#define SCHED_FIFO 1
38#define SCHED_RR 2
39#define SCHED_BATCH 3
40/* SCHED_ISO: reserved but not implemented yet */
41#define SCHED_IDLE 5
42/* Can be ORed in to make sure the process is reverted back to SCHED_NORMAL on fork */
43#define SCHED_RESET_ON_FORK 0x40000000
44
45#ifdef __KERNEL__
46
47struct sched_param {
48 int sched_priority;
49};
50
51#include <asm/param.h> /* for HZ */
52
53#include <linux/capability.h>
54#include <linux/threads.h>
55#include <linux/kernel.h>
56#include <linux/types.h>
57#include <linux/timex.h>
58#include <linux/jiffies.h>
59#include <linux/rbtree.h>
60#include <linux/thread_info.h>
61#include <linux/cpumask.h>
62#include <linux/errno.h>
63#include <linux/nodemask.h>
64#include <linux/mm_types.h>
65
66#include <asm/system.h>
67#include <asm/page.h>
68#include <asm/ptrace.h>
69#include <asm/cputime.h>
70
71#include <linux/smp.h>
72#include <linux/sem.h>
73#include <linux/signal.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/latencytop.h>
92#include <linux/cred.h>
93#include <linux/llist.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;
103struct blk_plug;
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(int cpu);
144extern unsigned long this_cpu_load(void);
145
146
147extern void calc_global_load(unsigned long ticks);
148
149extern unsigned long get_parent_ip(unsigned long addr);
150
151struct seq_file;
152struct cfs_rq;
153struct task_group;
154#ifdef CONFIG_SCHED_DEBUG
155extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
156extern void proc_sched_set_task(struct task_struct *p);
157extern void
158print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
159#else
160static inline void
161proc_sched_show_task(struct task_struct *p, struct seq_file *m)
162{
163}
164static inline void proc_sched_set_task(struct task_struct *p)
165{
166}
167static inline void
168print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
169{
170}
171#endif
172
173/*
174 * Task state bitmask. NOTE! These bits are also
175 * encoded in fs/proc/array.c: get_task_state().
176 *
177 * We have two separate sets of flags: task->state
178 * is about runnability, while task->exit_state are
179 * about the task exiting. Confusing, but this way
180 * modifying one set can't modify the other one by
181 * mistake.
182 */
183#define TASK_RUNNING 0
184#define TASK_INTERRUPTIBLE 1
185#define TASK_UNINTERRUPTIBLE 2
186#define __TASK_STOPPED 4
187#define __TASK_TRACED 8
188/* in tsk->exit_state */
189#define EXIT_ZOMBIE 16
190#define EXIT_DEAD 32
191/* in tsk->state again */
192#define TASK_DEAD 64
193#define TASK_WAKEKILL 128
194#define TASK_WAKING 256
195#define TASK_STATE_MAX 512
196
197#define TASK_STATE_TO_CHAR_STR "RSDTtZXxKW"
198
199extern char ___assert_task_state[1 - 2*!!(
200 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
201
202/* Convenience macros for the sake of set_task_state */
203#define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
204#define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
205#define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED)
206
207/* Convenience macros for the sake of wake_up */
208#define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
209#define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
210
211/* get_task_state() */
212#define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \
213 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
214 __TASK_TRACED)
215
216#define task_is_traced(task) ((task->state & __TASK_TRACED) != 0)
217#define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0)
218#define task_is_dead(task) ((task)->exit_state != 0)
219#define task_is_stopped_or_traced(task) \
220 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
221#define task_contributes_to_load(task) \
222 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
223 (task->flags & PF_FREEZING) == 0)
224
225#define __set_task_state(tsk, state_value) \
226 do { (tsk)->state = (state_value); } while (0)
227#define set_task_state(tsk, state_value) \
228 set_mb((tsk)->state, (state_value))
229
230/*
231 * set_current_state() includes a barrier so that the write of current->state
232 * is correctly serialised wrt the caller's subsequent test of whether to
233 * actually sleep:
234 *
235 * set_current_state(TASK_UNINTERRUPTIBLE);
236 * if (do_i_need_to_sleep())
237 * schedule();
238 *
239 * If the caller does not need such serialisation then use __set_current_state()
240 */
241#define __set_current_state(state_value) \
242 do { current->state = (state_value); } while (0)
243#define set_current_state(state_value) \
244 set_mb(current->state, (state_value))
245
246/* Task command name length */
247#define TASK_COMM_LEN 16
248
249#include <linux/spinlock.h>
250
251/*
252 * This serializes "schedule()" and also protects
253 * the run-queue from deletions/modifications (but
254 * _adding_ to the beginning of the run-queue has
255 * a separate lock).
256 */
257extern rwlock_t tasklist_lock;
258extern spinlock_t mmlist_lock;
259
260struct task_struct;
261
262#ifdef CONFIG_PROVE_RCU
263extern int lockdep_tasklist_lock_is_held(void);
264#endif /* #ifdef CONFIG_PROVE_RCU */
265
266extern void sched_init(void);
267extern void sched_init_smp(void);
268extern asmlinkage void schedule_tail(struct task_struct *prev);
269extern void init_idle(struct task_struct *idle, int cpu);
270extern void init_idle_bootup_task(struct task_struct *idle);
271
272extern int runqueue_is_locked(int cpu);
273
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;
318void lockup_detector_init(void);
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}
329static inline void lockup_detector_init(void)
330{
331}
332#endif
333
334#ifdef CONFIG_DETECT_HUNG_TASK
335extern unsigned int sysctl_hung_task_panic;
336extern unsigned long sysctl_hung_task_check_count;
337extern unsigned long sysctl_hung_task_timeout_secs;
338extern unsigned long sysctl_hung_task_warnings;
339extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
340 void __user *buffer,
341 size_t *lenp, loff_t *ppos);
342#else
343/* Avoid need for ifdefs elsewhere in the code */
344enum { sysctl_hung_task_timeout_secs = 0 };
345#endif
346
347/* Attach to any functions which should be ignored in wchan output. */
348#define __sched __attribute__((__section__(".sched.text")))
349
350/* Linker adds these: start and end of __sched functions */
351extern char __sched_text_start[], __sched_text_end[];
352
353/* Is this address in the __sched functions? */
354extern int in_sched_functions(unsigned long addr);
355
356#define MAX_SCHEDULE_TIMEOUT LONG_MAX
357extern signed long schedule_timeout(signed long timeout);
358extern signed long schedule_timeout_interruptible(signed long timeout);
359extern signed long schedule_timeout_killable(signed long timeout);
360extern signed long schedule_timeout_uninterruptible(signed long timeout);
361asmlinkage void schedule(void);
362extern int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner);
363
364struct nsproxy;
365struct user_namespace;
366
367/*
368 * Default maximum number of active map areas, this limits the number of vmas
369 * per mm struct. Users can overwrite this number by sysctl but there is a
370 * problem.
371 *
372 * When a program's coredump is generated as ELF format, a section is created
373 * per a vma. In ELF, the number of sections is represented in unsigned short.
374 * This means the number of sections should be smaller than 65535 at coredump.
375 * Because the kernel adds some informative sections to a image of program at
376 * generating coredump, we need some margin. The number of extra sections is
377 * 1-3 now and depends on arch. We use "5" as safe margin, here.
378 */
379#define MAPCOUNT_ELF_CORE_MARGIN (5)
380#define DEFAULT_MAX_MAP_COUNT (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
381
382extern int sysctl_max_map_count;
383
384#include <linux/aio.h>
385
386#ifdef CONFIG_MMU
387extern void arch_pick_mmap_layout(struct mm_struct *mm);
388extern unsigned long
389arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
390 unsigned long, unsigned long);
391extern unsigned long
392arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
393 unsigned long len, unsigned long pgoff,
394 unsigned long flags);
395extern void arch_unmap_area(struct mm_struct *, unsigned long);
396extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
397#else
398static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
399#endif
400
401
402extern void set_dumpable(struct mm_struct *mm, int value);
403extern int get_dumpable(struct mm_struct *mm);
404
405/* mm flags */
406/* dumpable bits */
407#define MMF_DUMPABLE 0 /* core dump is permitted */
408#define MMF_DUMP_SECURELY 1 /* core file is readable only by root */
409
410#define MMF_DUMPABLE_BITS 2
411#define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
412
413/* coredump filter bits */
414#define MMF_DUMP_ANON_PRIVATE 2
415#define MMF_DUMP_ANON_SHARED 3
416#define MMF_DUMP_MAPPED_PRIVATE 4
417#define MMF_DUMP_MAPPED_SHARED 5
418#define MMF_DUMP_ELF_HEADERS 6
419#define MMF_DUMP_HUGETLB_PRIVATE 7
420#define MMF_DUMP_HUGETLB_SHARED 8
421
422#define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS
423#define MMF_DUMP_FILTER_BITS 7
424#define MMF_DUMP_FILTER_MASK \
425 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
426#define MMF_DUMP_FILTER_DEFAULT \
427 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\
428 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
429
430#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
431# define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS)
432#else
433# define MMF_DUMP_MASK_DEFAULT_ELF 0
434#endif
435 /* leave room for more dump flags */
436#define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */
437#define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */
438
439#define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
440
441struct sighand_struct {
442 atomic_t count;
443 struct k_sigaction action[_NSIG];
444 spinlock_t siglock;
445 wait_queue_head_t signalfd_wqh;
446};
447
448struct pacct_struct {
449 int ac_flag;
450 long ac_exitcode;
451 unsigned long ac_mem;
452 cputime_t ac_utime, ac_stime;
453 unsigned long ac_minflt, ac_majflt;
454};
455
456struct cpu_itimer {
457 cputime_t expires;
458 cputime_t incr;
459 u32 error;
460 u32 incr_error;
461};
462
463/**
464 * struct task_cputime - collected CPU time counts
465 * @utime: time spent in user mode, in &cputime_t units
466 * @stime: time spent in kernel mode, in &cputime_t units
467 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds
468 *
469 * This structure groups together three kinds of CPU time that are
470 * tracked for threads and thread groups. Most things considering
471 * CPU time want to group these counts together and treat all three
472 * of them in parallel.
473 */
474struct task_cputime {
475 cputime_t utime;
476 cputime_t stime;
477 unsigned long long sum_exec_runtime;
478};
479/* Alternate field names when used to cache expirations. */
480#define prof_exp stime
481#define virt_exp utime
482#define sched_exp sum_exec_runtime
483
484#define INIT_CPUTIME \
485 (struct task_cputime) { \
486 .utime = cputime_zero, \
487 .stime = cputime_zero, \
488 .sum_exec_runtime = 0, \
489 }
490
491/*
492 * Disable preemption until the scheduler is running.
493 * Reset by start_kernel()->sched_init()->init_idle().
494 *
495 * We include PREEMPT_ACTIVE to avoid cond_resched() from working
496 * before the scheduler is active -- see should_resched().
497 */
498#define INIT_PREEMPT_COUNT (1 + PREEMPT_ACTIVE)
499
500/**
501 * struct thread_group_cputimer - thread group interval timer counts
502 * @cputime: thread group interval timers.
503 * @running: non-zero when there are timers running and
504 * @cputime receives updates.
505 * @lock: lock for fields in this struct.
506 *
507 * This structure contains the version of task_cputime, above, that is
508 * used for thread group CPU timer calculations.
509 */
510struct thread_group_cputimer {
511 struct task_cputime cputime;
512 int running;
513 raw_spinlock_t lock;
514};
515
516#include <linux/rwsem.h>
517struct autogroup;
518
519/*
520 * NOTE! "signal_struct" does not have its own
521 * locking, because a shared signal_struct always
522 * implies a shared sighand_struct, so locking
523 * sighand_struct is always a proper superset of
524 * the locking of signal_struct.
525 */
526struct signal_struct {
527 atomic_t sigcnt;
528 atomic_t live;
529 int nr_threads;
530
531 wait_queue_head_t wait_chldexit; /* for wait4() */
532
533 /* current thread group signal load-balancing target: */
534 struct task_struct *curr_target;
535
536 /* shared signal handling: */
537 struct sigpending shared_pending;
538
539 /* thread group exit support */
540 int group_exit_code;
541 /* overloaded:
542 * - notify group_exit_task when ->count is equal to notify_count
543 * - everyone except group_exit_task is stopped during signal delivery
544 * of fatal signals, group_exit_task processes the signal.
545 */
546 int notify_count;
547 struct task_struct *group_exit_task;
548
549 /* thread group stop support, overloads group_exit_code too */
550 int group_stop_count;
551 unsigned int flags; /* see SIGNAL_* flags below */
552
553 /* POSIX.1b Interval Timers */
554 struct list_head posix_timers;
555
556 /* ITIMER_REAL timer for the process */
557 struct hrtimer real_timer;
558 struct pid *leader_pid;
559 ktime_t it_real_incr;
560
561 /*
562 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
563 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
564 * values are defined to 0 and 1 respectively
565 */
566 struct cpu_itimer it[2];
567
568 /*
569 * Thread group totals for process CPU timers.
570 * See thread_group_cputimer(), et al, for details.
571 */
572 struct thread_group_cputimer cputimer;
573
574 /* Earliest-expiration cache. */
575 struct task_cputime cputime_expires;
576
577 struct list_head cpu_timers[3];
578
579 struct pid *tty_old_pgrp;
580
581 /* boolean value for session group leader */
582 int leader;
583
584 struct tty_struct *tty; /* NULL if no tty */
585
586#ifdef CONFIG_SCHED_AUTOGROUP
587 struct autogroup *autogroup;
588#endif
589 /*
590 * Cumulative resource counters for dead threads in the group,
591 * and for reaped dead child processes forked by this group.
592 * Live threads maintain their own counters and add to these
593 * in __exit_signal, except for the group leader.
594 */
595 cputime_t utime, stime, cutime, cstime;
596 cputime_t gtime;
597 cputime_t cgtime;
598#ifndef CONFIG_VIRT_CPU_ACCOUNTING
599 cputime_t prev_utime, prev_stime;
600#endif
601 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
602 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
603 unsigned long inblock, oublock, cinblock, coublock;
604 unsigned long maxrss, cmaxrss;
605 struct task_io_accounting ioac;
606
607 /*
608 * Cumulative ns of schedule CPU time fo dead threads in the
609 * group, not including a zombie group leader, (This only differs
610 * from jiffies_to_ns(utime + stime) if sched_clock uses something
611 * other than jiffies.)
612 */
613 unsigned long long sum_sched_runtime;
614
615 /*
616 * We don't bother to synchronize most readers of this at all,
617 * because there is no reader checking a limit that actually needs
618 * to get both rlim_cur and rlim_max atomically, and either one
619 * alone is a single word that can safely be read normally.
620 * getrlimit/setrlimit use task_lock(current->group_leader) to
621 * protect this instead of the siglock, because they really
622 * have no need to disable irqs.
623 */
624 struct rlimit rlim[RLIM_NLIMITS];
625
626#ifdef CONFIG_BSD_PROCESS_ACCT
627 struct pacct_struct pacct; /* per-process accounting information */
628#endif
629#ifdef CONFIG_TASKSTATS
630 struct taskstats *stats;
631#endif
632#ifdef CONFIG_AUDIT
633 unsigned audit_tty;
634 struct tty_audit_buf *tty_audit_buf;
635#endif
636#ifdef CONFIG_CGROUPS
637 /*
638 * The threadgroup_fork_lock prevents threads from forking with
639 * CLONE_THREAD while held for writing. Use this for fork-sensitive
640 * threadgroup-wide operations. It's taken for reading in fork.c in
641 * copy_process().
642 * Currently only needed write-side by cgroups.
643 */
644 struct rw_semaphore threadgroup_fork_lock;
645#endif
646
647 int oom_adj; /* OOM kill score adjustment (bit shift) */
648 int oom_score_adj; /* OOM kill score adjustment */
649 int oom_score_adj_min; /* OOM kill score adjustment minimum value.
650 * Only settable by CAP_SYS_RESOURCE. */
651
652 struct mutex cred_guard_mutex; /* guard against foreign influences on
653 * credential calculations
654 * (notably. ptrace) */
655};
656
657/* Context switch must be unlocked if interrupts are to be enabled */
658#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
659# define __ARCH_WANT_UNLOCKED_CTXSW
660#endif
661
662/*
663 * Bits in flags field of signal_struct.
664 */
665#define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */
666#define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */
667#define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */
668/*
669 * Pending notifications to parent.
670 */
671#define SIGNAL_CLD_STOPPED 0x00000010
672#define SIGNAL_CLD_CONTINUED 0x00000020
673#define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
674
675#define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */
676
677/* If true, all threads except ->group_exit_task have pending SIGKILL */
678static inline int signal_group_exit(const struct signal_struct *sig)
679{
680 return (sig->flags & SIGNAL_GROUP_EXIT) ||
681 (sig->group_exit_task != NULL);
682}
683
684/*
685 * Some day this will be a full-fledged user tracking system..
686 */
687struct user_struct {
688 atomic_t __count; /* reference count */
689 atomic_t processes; /* How many processes does this user have? */
690 atomic_t files; /* How many open files does this user have? */
691 atomic_t sigpending; /* How many pending signals does this user have? */
692#ifdef CONFIG_INOTIFY_USER
693 atomic_t inotify_watches; /* How many inotify watches does this user have? */
694 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */
695#endif
696#ifdef CONFIG_FANOTIFY
697 atomic_t fanotify_listeners;
698#endif
699#ifdef CONFIG_EPOLL
700 atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
701#endif
702#ifdef CONFIG_POSIX_MQUEUE
703 /* protected by mq_lock */
704 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
705#endif
706 unsigned long locked_shm; /* How many pages of mlocked shm ? */
707
708#ifdef CONFIG_KEYS
709 struct key *uid_keyring; /* UID specific keyring */
710 struct key *session_keyring; /* UID's default session keyring */
711#endif
712
713 /* Hash table maintenance information */
714 struct hlist_node uidhash_node;
715 uid_t uid;
716 struct user_namespace *user_ns;
717
718#ifdef CONFIG_PERF_EVENTS
719 atomic_long_t locked_vm;
720#endif
721};
722
723extern int uids_sysfs_init(void);
724
725extern struct user_struct *find_user(uid_t);
726
727extern struct user_struct root_user;
728#define INIT_USER (&root_user)
729
730
731struct backing_dev_info;
732struct reclaim_state;
733
734#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
735struct sched_info {
736 /* cumulative counters */
737 unsigned long pcount; /* # of times run on this cpu */
738 unsigned long long run_delay; /* time spent waiting on a runqueue */
739
740 /* timestamps */
741 unsigned long long last_arrival,/* when we last ran on a cpu */
742 last_queued; /* when we were last queued to run */
743};
744#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
745
746#ifdef CONFIG_TASK_DELAY_ACCT
747struct task_delay_info {
748 spinlock_t lock;
749 unsigned int flags; /* Private per-task flags */
750
751 /* For each stat XXX, add following, aligned appropriately
752 *
753 * struct timespec XXX_start, XXX_end;
754 * u64 XXX_delay;
755 * u32 XXX_count;
756 *
757 * Atomicity of updates to XXX_delay, XXX_count protected by
758 * single lock above (split into XXX_lock if contention is an issue).
759 */
760
761 /*
762 * XXX_count is incremented on every XXX operation, the delay
763 * associated with the operation is added to XXX_delay.
764 * XXX_delay contains the accumulated delay time in nanoseconds.
765 */
766 struct timespec blkio_start, blkio_end; /* Shared by blkio, swapin */
767 u64 blkio_delay; /* wait for sync block io completion */
768 u64 swapin_delay; /* wait for swapin block io completion */
769 u32 blkio_count; /* total count of the number of sync block */
770 /* io operations performed */
771 u32 swapin_count; /* total count of the number of swapin block */
772 /* io operations performed */
773
774 struct timespec freepages_start, freepages_end;
775 u64 freepages_delay; /* wait for memory reclaim */
776 u32 freepages_count; /* total count of memory reclaim */
777};
778#endif /* CONFIG_TASK_DELAY_ACCT */
779
780static inline int sched_info_on(void)
781{
782#ifdef CONFIG_SCHEDSTATS
783 return 1;
784#elif defined(CONFIG_TASK_DELAY_ACCT)
785 extern int delayacct_on;
786 return delayacct_on;
787#else
788 return 0;
789#endif
790}
791
792enum cpu_idle_type {
793 CPU_IDLE,
794 CPU_NOT_IDLE,
795 CPU_NEWLY_IDLE,
796 CPU_MAX_IDLE_TYPES
797};
798
799/*
800 * Increase resolution of nice-level calculations for 64-bit architectures.
801 * The extra resolution improves shares distribution and load balancing of
802 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
803 * hierarchies, especially on larger systems. This is not a user-visible change
804 * and does not change the user-interface for setting shares/weights.
805 *
806 * We increase resolution only if we have enough bits to allow this increased
807 * resolution (i.e. BITS_PER_LONG > 32). The costs for increasing resolution
808 * when BITS_PER_LONG <= 32 are pretty high and the returns do not justify the
809 * increased costs.
810 */
811#if 0 /* BITS_PER_LONG > 32 -- currently broken: it increases power usage under light load */
812# define SCHED_LOAD_RESOLUTION 10
813# define scale_load(w) ((w) << SCHED_LOAD_RESOLUTION)
814# define scale_load_down(w) ((w) >> SCHED_LOAD_RESOLUTION)
815#else
816# define SCHED_LOAD_RESOLUTION 0
817# define scale_load(w) (w)
818# define scale_load_down(w) (w)
819#endif
820
821#define SCHED_LOAD_SHIFT (10 + SCHED_LOAD_RESOLUTION)
822#define SCHED_LOAD_SCALE (1L << SCHED_LOAD_SHIFT)
823
824/*
825 * Increase resolution of cpu_power calculations
826 */
827#define SCHED_POWER_SHIFT 10
828#define SCHED_POWER_SCALE (1L << SCHED_POWER_SHIFT)
829
830/*
831 * sched-domains (multiprocessor balancing) declarations:
832 */
833#ifdef CONFIG_SMP
834#define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */
835#define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */
836#define SD_BALANCE_EXEC 0x0004 /* Balance on exec */
837#define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */
838#define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */
839#define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */
840#define SD_PREFER_LOCAL 0x0040 /* Prefer to keep tasks local to this domain */
841#define SD_SHARE_CPUPOWER 0x0080 /* Domain members share cpu power */
842#define SD_POWERSAVINGS_BALANCE 0x0100 /* Balance for power savings */
843#define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */
844#define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */
845#define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */
846#define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */
847#define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */
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 if (!sched_mc_power_savings)
868 return SD_PREFER_SIBLING;
869
870 return 0;
871}
872
873static inline int sd_balance_for_package_power(void)
874{
875 if (sched_mc_power_savings | sched_smt_power_savings)
876 return SD_POWERSAVINGS_BALANCE;
877
878 return SD_PREFER_SIBLING;
879}
880
881extern int __weak arch_sd_sibiling_asym_packing(void);
882
883/*
884 * Optimise SD flags for power savings:
885 * SD_BALANCE_NEWIDLE helps aggressive task consolidation and power savings.
886 * Keep default SD flags if sched_{smt,mc}_power_saving=0
887 */
888
889static inline int sd_power_saving_flags(void)
890{
891 if (sched_mc_power_savings | sched_smt_power_savings)
892 return SD_BALANCE_NEWIDLE;
893
894 return 0;
895}
896
897struct sched_group_power {
898 atomic_t ref;
899 /*
900 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
901 * single CPU.
902 */
903 unsigned int power, power_orig;
904};
905
906struct sched_group {
907 struct sched_group *next; /* Must be a circular list */
908 atomic_t ref;
909
910 unsigned int group_weight;
911 struct sched_group_power *sgp;
912
913 /*
914 * The CPUs this group covers.
915 *
916 * NOTE: this field is variable length. (Allocated dynamically
917 * by attaching extra space to the end of the structure,
918 * depending on how many CPUs the kernel has booted up with)
919 */
920 unsigned long cpumask[0];
921};
922
923static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
924{
925 return to_cpumask(sg->cpumask);
926}
927
928struct sched_domain_attr {
929 int relax_domain_level;
930};
931
932#define SD_ATTR_INIT (struct sched_domain_attr) { \
933 .relax_domain_level = -1, \
934}
935
936extern int sched_domain_level_max;
937
938struct sched_domain {
939 /* These fields must be setup */
940 struct sched_domain *parent; /* top domain must be null terminated */
941 struct sched_domain *child; /* bottom domain must be null terminated */
942 struct sched_group *groups; /* the balancing groups of the domain */
943 unsigned long min_interval; /* Minimum balance interval ms */
944 unsigned long max_interval; /* Maximum balance interval ms */
945 unsigned int busy_factor; /* less balancing by factor if busy */
946 unsigned int imbalance_pct; /* No balance until over watermark */
947 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */
948 unsigned int busy_idx;
949 unsigned int idle_idx;
950 unsigned int newidle_idx;
951 unsigned int wake_idx;
952 unsigned int forkexec_idx;
953 unsigned int smt_gain;
954 int flags; /* See SD_* */
955 int level;
956
957 /* Runtime fields. */
958 unsigned long last_balance; /* init to jiffies. units in jiffies */
959 unsigned int balance_interval; /* initialise to 1. units in ms. */
960 unsigned int nr_balance_failed; /* initialise to 0 */
961
962 u64 last_update;
963
964#ifdef CONFIG_SCHEDSTATS
965 /* load_balance() stats */
966 unsigned int lb_count[CPU_MAX_IDLE_TYPES];
967 unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
968 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
969 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
970 unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
971 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
972 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
973 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
974
975 /* Active load balancing */
976 unsigned int alb_count;
977 unsigned int alb_failed;
978 unsigned int alb_pushed;
979
980 /* SD_BALANCE_EXEC stats */
981 unsigned int sbe_count;
982 unsigned int sbe_balanced;
983 unsigned int sbe_pushed;
984
985 /* SD_BALANCE_FORK stats */
986 unsigned int sbf_count;
987 unsigned int sbf_balanced;
988 unsigned int sbf_pushed;
989
990 /* try_to_wake_up() stats */
991 unsigned int ttwu_wake_remote;
992 unsigned int ttwu_move_affine;
993 unsigned int ttwu_move_balance;
994#endif
995#ifdef CONFIG_SCHED_DEBUG
996 char *name;
997#endif
998 union {
999 void *private; /* used during construction */
1000 struct rcu_head rcu; /* used during destruction */
1001 };
1002
1003 unsigned int span_weight;
1004 /*
1005 * Span of all CPUs in this domain.
1006 *
1007 * NOTE: this field is variable length. (Allocated dynamically
1008 * by attaching extra space to the end of the structure,
1009 * depending on how many CPUs the kernel has booted up with)
1010 */
1011 unsigned long span[0];
1012};
1013
1014static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
1015{
1016 return to_cpumask(sd->span);
1017}
1018
1019extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1020 struct sched_domain_attr *dattr_new);
1021
1022/* Allocate an array of sched domains, for partition_sched_domains(). */
1023cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
1024void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
1025
1026/* Test a flag in parent sched domain */
1027static inline int test_sd_parent(struct sched_domain *sd, int flag)
1028{
1029 if (sd->parent && (sd->parent->flags & flag))
1030 return 1;
1031
1032 return 0;
1033}
1034
1035unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu);
1036unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu);
1037
1038#else /* CONFIG_SMP */
1039
1040struct sched_domain_attr;
1041
1042static inline void
1043partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1044 struct sched_domain_attr *dattr_new)
1045{
1046}
1047#endif /* !CONFIG_SMP */
1048
1049
1050struct io_context; /* See blkdev.h */
1051
1052
1053#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1054extern void prefetch_stack(struct task_struct *t);
1055#else
1056static inline void prefetch_stack(struct task_struct *t) { }
1057#endif
1058
1059struct audit_context; /* See audit.c */
1060struct mempolicy;
1061struct pipe_inode_info;
1062struct uts_namespace;
1063
1064struct rq;
1065struct sched_domain;
1066
1067/*
1068 * wake flags
1069 */
1070#define WF_SYNC 0x01 /* waker goes to sleep after wakup */
1071#define WF_FORK 0x02 /* child wakeup after fork */
1072#define WF_MIGRATED 0x04 /* internal use, task got migrated */
1073
1074#define ENQUEUE_WAKEUP 1
1075#define ENQUEUE_HEAD 2
1076#ifdef CONFIG_SMP
1077#define ENQUEUE_WAKING 4 /* sched_class::task_waking was called */
1078#else
1079#define ENQUEUE_WAKING 0
1080#endif
1081
1082#define DEQUEUE_SLEEP 1
1083
1084struct sched_class {
1085 const struct sched_class *next;
1086
1087 void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1088 void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1089 void (*yield_task) (struct rq *rq);
1090 bool (*yield_to_task) (struct rq *rq, struct task_struct *p, bool preempt);
1091
1092 void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
1093
1094 struct task_struct * (*pick_next_task) (struct rq *rq);
1095 void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1096
1097#ifdef CONFIG_SMP
1098 int (*select_task_rq)(struct task_struct *p, int sd_flag, int flags);
1099
1100 void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
1101 void (*post_schedule) (struct rq *this_rq);
1102 void (*task_waking) (struct task_struct *task);
1103 void (*task_woken) (struct rq *this_rq, struct task_struct *task);
1104
1105 void (*set_cpus_allowed)(struct task_struct *p,
1106 const struct cpumask *newmask);
1107
1108 void (*rq_online)(struct rq *rq);
1109 void (*rq_offline)(struct rq *rq);
1110#endif
1111
1112 void (*set_curr_task) (struct rq *rq);
1113 void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1114 void (*task_fork) (struct task_struct *p);
1115
1116 void (*switched_from) (struct rq *this_rq, struct task_struct *task);
1117 void (*switched_to) (struct rq *this_rq, struct task_struct *task);
1118 void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1119 int oldprio);
1120
1121 unsigned int (*get_rr_interval) (struct rq *rq,
1122 struct task_struct *task);
1123
1124#ifdef CONFIG_FAIR_GROUP_SCHED
1125 void (*task_move_group) (struct task_struct *p, int on_rq);
1126#endif
1127};
1128
1129struct load_weight {
1130 unsigned long weight, inv_weight;
1131};
1132
1133#ifdef CONFIG_SCHEDSTATS
1134struct sched_statistics {
1135 u64 wait_start;
1136 u64 wait_max;
1137 u64 wait_count;
1138 u64 wait_sum;
1139 u64 iowait_count;
1140 u64 iowait_sum;
1141
1142 u64 sleep_start;
1143 u64 sleep_max;
1144 s64 sum_sleep_runtime;
1145
1146 u64 block_start;
1147 u64 block_max;
1148 u64 exec_max;
1149 u64 slice_max;
1150
1151 u64 nr_migrations_cold;
1152 u64 nr_failed_migrations_affine;
1153 u64 nr_failed_migrations_running;
1154 u64 nr_failed_migrations_hot;
1155 u64 nr_forced_migrations;
1156
1157 u64 nr_wakeups;
1158 u64 nr_wakeups_sync;
1159 u64 nr_wakeups_migrate;
1160 u64 nr_wakeups_local;
1161 u64 nr_wakeups_remote;
1162 u64 nr_wakeups_affine;
1163 u64 nr_wakeups_affine_attempts;
1164 u64 nr_wakeups_passive;
1165 u64 nr_wakeups_idle;
1166};
1167#endif
1168
1169struct sched_entity {
1170 struct load_weight load; /* for load-balancing */
1171 struct rb_node run_node;
1172 struct list_head group_node;
1173 unsigned int on_rq;
1174
1175 u64 exec_start;
1176 u64 sum_exec_runtime;
1177 u64 vruntime;
1178 u64 prev_sum_exec_runtime;
1179
1180 u64 nr_migrations;
1181
1182#ifdef CONFIG_SCHEDSTATS
1183 struct sched_statistics statistics;
1184#endif
1185
1186#ifdef CONFIG_FAIR_GROUP_SCHED
1187 struct sched_entity *parent;
1188 /* rq on which this entity is (to be) queued: */
1189 struct cfs_rq *cfs_rq;
1190 /* rq "owned" by this entity/group: */
1191 struct cfs_rq *my_q;
1192#endif
1193};
1194
1195struct sched_rt_entity {
1196 struct list_head run_list;
1197 unsigned long timeout;
1198 unsigned int time_slice;
1199 int nr_cpus_allowed;
1200
1201 struct sched_rt_entity *back;
1202#ifdef CONFIG_RT_GROUP_SCHED
1203 struct sched_rt_entity *parent;
1204 /* rq on which this entity is (to be) queued: */
1205 struct rt_rq *rt_rq;
1206 /* rq "owned" by this entity/group: */
1207 struct rt_rq *my_q;
1208#endif
1209};
1210
1211struct rcu_node;
1212
1213enum perf_event_task_context {
1214 perf_invalid_context = -1,
1215 perf_hw_context = 0,
1216 perf_sw_context,
1217 perf_nr_task_contexts,
1218};
1219
1220struct task_struct {
1221 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
1222 void *stack;
1223 atomic_t usage;
1224 unsigned int flags; /* per process flags, defined below */
1225 unsigned int ptrace;
1226
1227#ifdef CONFIG_SMP
1228 struct llist_node wake_entry;
1229 int on_cpu;
1230#endif
1231 int on_rq;
1232
1233 int prio, static_prio, normal_prio;
1234 unsigned int rt_priority;
1235 const struct sched_class *sched_class;
1236 struct sched_entity se;
1237 struct sched_rt_entity rt;
1238
1239#ifdef CONFIG_PREEMPT_NOTIFIERS
1240 /* list of struct preempt_notifier: */
1241 struct hlist_head preempt_notifiers;
1242#endif
1243
1244 /*
1245 * fpu_counter contains the number of consecutive context switches
1246 * that the FPU is used. If this is over a threshold, the lazy fpu
1247 * saving becomes unlazy to save the trap. This is an unsigned char
1248 * so that after 256 times the counter wraps and the behavior turns
1249 * lazy again; this to deal with bursty apps that only use FPU for
1250 * a short time
1251 */
1252 unsigned char fpu_counter;
1253#ifdef CONFIG_BLK_DEV_IO_TRACE
1254 unsigned int btrace_seq;
1255#endif
1256
1257 unsigned int policy;
1258 cpumask_t cpus_allowed;
1259
1260#ifdef CONFIG_PREEMPT_RCU
1261 int rcu_read_lock_nesting;
1262 char rcu_read_unlock_special;
1263 struct list_head rcu_node_entry;
1264#endif /* #ifdef CONFIG_PREEMPT_RCU */
1265#ifdef CONFIG_TREE_PREEMPT_RCU
1266 struct rcu_node *rcu_blocked_node;
1267#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1268#ifdef CONFIG_RCU_BOOST
1269 struct rt_mutex *rcu_boost_mutex;
1270#endif /* #ifdef CONFIG_RCU_BOOST */
1271
1272#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1273 struct sched_info sched_info;
1274#endif
1275
1276 struct list_head tasks;
1277#ifdef CONFIG_SMP
1278 struct plist_node pushable_tasks;
1279#endif
1280
1281 struct mm_struct *mm, *active_mm;
1282#ifdef CONFIG_COMPAT_BRK
1283 unsigned brk_randomized:1;
1284#endif
1285#if defined(SPLIT_RSS_COUNTING)
1286 struct task_rss_stat rss_stat;
1287#endif
1288/* task state */
1289 int exit_state;
1290 int exit_code, exit_signal;
1291 int pdeath_signal; /* The signal sent when the parent dies */
1292 unsigned int jobctl; /* JOBCTL_*, siglock protected */
1293 /* ??? */
1294 unsigned int personality;
1295 unsigned did_exec:1;
1296 unsigned in_execve:1; /* Tell the LSMs that the process is doing an
1297 * execve */
1298 unsigned in_iowait:1;
1299
1300
1301 /* Revert to default priority/policy when forking */
1302 unsigned sched_reset_on_fork:1;
1303 unsigned sched_contributes_to_load:1;
1304
1305 pid_t pid;
1306 pid_t tgid;
1307
1308#ifdef CONFIG_CC_STACKPROTECTOR
1309 /* Canary value for the -fstack-protector gcc feature */
1310 unsigned long stack_canary;
1311#endif
1312
1313 /*
1314 * pointers to (original) parent process, youngest child, younger sibling,
1315 * older sibling, respectively. (p->father can be replaced with
1316 * p->real_parent->pid)
1317 */
1318 struct task_struct *real_parent; /* real parent process */
1319 struct task_struct *parent; /* recipient of SIGCHLD, wait4() reports */
1320 /*
1321 * children/sibling forms the list of my natural children
1322 */
1323 struct list_head children; /* list of my children */
1324 struct list_head sibling; /* linkage in my parent's children list */
1325 struct task_struct *group_leader; /* threadgroup leader */
1326
1327 /*
1328 * ptraced is the list of tasks this task is using ptrace on.
1329 * This includes both natural children and PTRACE_ATTACH targets.
1330 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1331 */
1332 struct list_head ptraced;
1333 struct list_head ptrace_entry;
1334
1335 /* PID/PID hash table linkage. */
1336 struct pid_link pids[PIDTYPE_MAX];
1337 struct list_head thread_group;
1338
1339 struct completion *vfork_done; /* for vfork() */
1340 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
1341 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
1342
1343 cputime_t utime, stime, utimescaled, stimescaled;
1344 cputime_t gtime;
1345#ifndef CONFIG_VIRT_CPU_ACCOUNTING
1346 cputime_t prev_utime, prev_stime;
1347#endif
1348 unsigned long nvcsw, nivcsw; /* context switch counts */
1349 struct timespec start_time; /* monotonic time */
1350 struct timespec real_start_time; /* boot based time */
1351/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1352 unsigned long min_flt, maj_flt;
1353
1354 struct task_cputime cputime_expires;
1355 struct list_head cpu_timers[3];
1356
1357/* process credentials */
1358 const struct cred __rcu *real_cred; /* objective and real subjective task
1359 * credentials (COW) */
1360 const struct cred __rcu *cred; /* effective (overridable) subjective task
1361 * credentials (COW) */
1362 struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */
1363
1364 char comm[TASK_COMM_LEN]; /* executable name excluding path
1365 - access with [gs]et_task_comm (which lock
1366 it with task_lock())
1367 - initialized normally by setup_new_exec */
1368/* file system info */
1369 int link_count, total_link_count;
1370#ifdef CONFIG_SYSVIPC
1371/* ipc stuff */
1372 struct sysv_sem sysvsem;
1373#endif
1374#ifdef CONFIG_DETECT_HUNG_TASK
1375/* hung task detection */
1376 unsigned long last_switch_count;
1377#endif
1378/* CPU-specific state of this task */
1379 struct thread_struct thread;
1380/* filesystem information */
1381 struct fs_struct *fs;
1382/* open file information */
1383 struct files_struct *files;
1384/* namespaces */
1385 struct nsproxy *nsproxy;
1386/* signal handlers */
1387 struct signal_struct *signal;
1388 struct sighand_struct *sighand;
1389
1390 sigset_t blocked, real_blocked;
1391 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
1392 struct sigpending pending;
1393
1394 unsigned long sas_ss_sp;
1395 size_t sas_ss_size;
1396 int (*notifier)(void *priv);
1397 void *notifier_data;
1398 sigset_t *notifier_mask;
1399 struct audit_context *audit_context;
1400#ifdef CONFIG_AUDITSYSCALL
1401 uid_t loginuid;
1402 unsigned int sessionid;
1403#endif
1404 seccomp_t seccomp;
1405
1406/* Thread group tracking */
1407 u32 parent_exec_id;
1408 u32 self_exec_id;
1409/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1410 * mempolicy */
1411 spinlock_t alloc_lock;
1412
1413#ifdef CONFIG_GENERIC_HARDIRQS
1414 /* IRQ handler threads */
1415 struct irqaction *irqaction;
1416#endif
1417
1418 /* Protection of the PI data structures: */
1419 raw_spinlock_t pi_lock;
1420
1421#ifdef CONFIG_RT_MUTEXES
1422 /* PI waiters blocked on a rt_mutex held by this task */
1423 struct plist_head pi_waiters;
1424 /* Deadlock detection and priority inheritance handling */
1425 struct rt_mutex_waiter *pi_blocked_on;
1426#endif
1427
1428#ifdef CONFIG_DEBUG_MUTEXES
1429 /* mutex deadlock detection */
1430 struct mutex_waiter *blocked_on;
1431#endif
1432#ifdef CONFIG_TRACE_IRQFLAGS
1433 unsigned int irq_events;
1434 unsigned long hardirq_enable_ip;
1435 unsigned long hardirq_disable_ip;
1436 unsigned int hardirq_enable_event;
1437 unsigned int hardirq_disable_event;
1438 int hardirqs_enabled;
1439 int hardirq_context;
1440 unsigned long softirq_disable_ip;
1441 unsigned long softirq_enable_ip;
1442 unsigned int softirq_disable_event;
1443 unsigned int softirq_enable_event;
1444 int softirqs_enabled;
1445 int softirq_context;
1446#endif
1447#ifdef CONFIG_LOCKDEP
1448# define MAX_LOCK_DEPTH 48UL
1449 u64 curr_chain_key;
1450 int lockdep_depth;
1451 unsigned int lockdep_recursion;
1452 struct held_lock held_locks[MAX_LOCK_DEPTH];
1453 gfp_t lockdep_reclaim_gfp;
1454#endif
1455
1456/* journalling filesystem info */
1457 void *journal_info;
1458
1459/* stacked block device info */
1460 struct bio_list *bio_list;
1461
1462#ifdef CONFIG_BLOCK
1463/* stack plugging */
1464 struct blk_plug *plug;
1465#endif
1466
1467/* VM state */
1468 struct reclaim_state *reclaim_state;
1469
1470 struct backing_dev_info *backing_dev_info;
1471
1472 struct io_context *io_context;
1473
1474 unsigned long ptrace_message;
1475 siginfo_t *last_siginfo; /* For ptrace use. */
1476 struct task_io_accounting ioac;
1477#if defined(CONFIG_TASK_XACCT)
1478 u64 acct_rss_mem1; /* accumulated rss usage */
1479 u64 acct_vm_mem1; /* accumulated virtual memory usage */
1480 cputime_t acct_timexpd; /* stime + utime since last update */
1481#endif
1482#ifdef CONFIG_CPUSETS
1483 nodemask_t mems_allowed; /* Protected by alloc_lock */
1484 int mems_allowed_change_disable;
1485 int cpuset_mem_spread_rotor;
1486 int cpuset_slab_spread_rotor;
1487#endif
1488#ifdef CONFIG_CGROUPS
1489 /* Control Group info protected by css_set_lock */
1490 struct css_set __rcu *cgroups;
1491 /* cg_list protected by css_set_lock and tsk->alloc_lock */
1492 struct list_head cg_list;
1493#endif
1494#ifdef CONFIG_FUTEX
1495 struct robust_list_head __user *robust_list;
1496#ifdef CONFIG_COMPAT
1497 struct compat_robust_list_head __user *compat_robust_list;
1498#endif
1499 struct list_head pi_state_list;
1500 struct futex_pi_state *pi_state_cache;
1501#endif
1502#ifdef CONFIG_PERF_EVENTS
1503 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1504 struct mutex perf_event_mutex;
1505 struct list_head perf_event_list;
1506#endif
1507#ifdef CONFIG_NUMA
1508 struct mempolicy *mempolicy; /* Protected by alloc_lock */
1509 short il_next;
1510 short pref_node_fork;
1511#endif
1512 struct rcu_head rcu;
1513
1514 /*
1515 * cache last used pipe for splice
1516 */
1517 struct pipe_inode_info *splice_pipe;
1518#ifdef CONFIG_TASK_DELAY_ACCT
1519 struct task_delay_info *delays;
1520#endif
1521#ifdef CONFIG_FAULT_INJECTION
1522 int make_it_fail;
1523#endif
1524 /*
1525 * when (nr_dirtied >= nr_dirtied_pause), it's time to call
1526 * balance_dirty_pages() for some dirty throttling pause
1527 */
1528 int nr_dirtied;
1529 int nr_dirtied_pause;
1530
1531#ifdef CONFIG_LATENCYTOP
1532 int latency_record_count;
1533 struct latency_record latency_record[LT_SAVECOUNT];
1534#endif
1535 /*
1536 * time slack values; these are used to round up poll() and
1537 * select() etc timeout values. These are in nanoseconds.
1538 */
1539 unsigned long timer_slack_ns;
1540 unsigned long default_timer_slack_ns;
1541
1542 struct list_head *scm_work_list;
1543#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1544 /* Index of current stored address in ret_stack */
1545 int curr_ret_stack;
1546 /* Stack of return addresses for return function tracing */
1547 struct ftrace_ret_stack *ret_stack;
1548 /* time stamp for last schedule */
1549 unsigned long long ftrace_timestamp;
1550 /*
1551 * Number of functions that haven't been traced
1552 * because of depth overrun.
1553 */
1554 atomic_t trace_overrun;
1555 /* Pause for the tracing */
1556 atomic_t tracing_graph_pause;
1557#endif
1558#ifdef CONFIG_TRACING
1559 /* state flags for use by tracers */
1560 unsigned long trace;
1561 /* bitmask and counter of trace recursion */
1562 unsigned long trace_recursion;
1563#endif /* CONFIG_TRACING */
1564#ifdef CONFIG_CGROUP_MEM_RES_CTLR /* memcg uses this to do batch job */
1565 struct memcg_batch_info {
1566 int do_batch; /* incremented when batch uncharge started */
1567 struct mem_cgroup *memcg; /* target memcg of uncharge */
1568 unsigned long nr_pages; /* uncharged usage */
1569 unsigned long memsw_nr_pages; /* uncharged mem+swap usage */
1570 } memcg_batch;
1571#endif
1572#ifdef CONFIG_HAVE_HW_BREAKPOINT
1573 atomic_t ptrace_bp_refcnt;
1574#endif
1575};
1576
1577/* Future-safe accessor for struct task_struct's cpus_allowed. */
1578#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1579
1580/*
1581 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1582 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1583 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1584 * values are inverted: lower p->prio value means higher priority.
1585 *
1586 * The MAX_USER_RT_PRIO value allows the actual maximum
1587 * RT priority to be separate from the value exported to
1588 * user-space. This allows kernel threads to set their
1589 * priority to a value higher than any user task. Note:
1590 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1591 */
1592
1593#define MAX_USER_RT_PRIO 100
1594#define MAX_RT_PRIO MAX_USER_RT_PRIO
1595
1596#define MAX_PRIO (MAX_RT_PRIO + 40)
1597#define DEFAULT_PRIO (MAX_RT_PRIO + 20)
1598
1599static inline int rt_prio(int prio)
1600{
1601 if (unlikely(prio < MAX_RT_PRIO))
1602 return 1;
1603 return 0;
1604}
1605
1606static inline int rt_task(struct task_struct *p)
1607{
1608 return rt_prio(p->prio);
1609}
1610
1611static inline struct pid *task_pid(struct task_struct *task)
1612{
1613 return task->pids[PIDTYPE_PID].pid;
1614}
1615
1616static inline struct pid *task_tgid(struct task_struct *task)
1617{
1618 return task->group_leader->pids[PIDTYPE_PID].pid;
1619}
1620
1621/*
1622 * Without tasklist or rcu lock it is not safe to dereference
1623 * the result of task_pgrp/task_session even if task == current,
1624 * we can race with another thread doing sys_setsid/sys_setpgid.
1625 */
1626static inline struct pid *task_pgrp(struct task_struct *task)
1627{
1628 return task->group_leader->pids[PIDTYPE_PGID].pid;
1629}
1630
1631static inline struct pid *task_session(struct task_struct *task)
1632{
1633 return task->group_leader->pids[PIDTYPE_SID].pid;
1634}
1635
1636struct pid_namespace;
1637
1638/*
1639 * the helpers to get the task's different pids as they are seen
1640 * from various namespaces
1641 *
1642 * task_xid_nr() : global id, i.e. the id seen from the init namespace;
1643 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of
1644 * current.
1645 * task_xid_nr_ns() : id seen from the ns specified;
1646 *
1647 * set_task_vxid() : assigns a virtual id to a task;
1648 *
1649 * see also pid_nr() etc in include/linux/pid.h
1650 */
1651pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1652 struct pid_namespace *ns);
1653
1654static inline pid_t task_pid_nr(struct task_struct *tsk)
1655{
1656 return tsk->pid;
1657}
1658
1659static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1660 struct pid_namespace *ns)
1661{
1662 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1663}
1664
1665static inline pid_t task_pid_vnr(struct task_struct *tsk)
1666{
1667 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1668}
1669
1670
1671static inline pid_t task_tgid_nr(struct task_struct *tsk)
1672{
1673 return tsk->tgid;
1674}
1675
1676pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1677
1678static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1679{
1680 return pid_vnr(task_tgid(tsk));
1681}
1682
1683
1684static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1685 struct pid_namespace *ns)
1686{
1687 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1688}
1689
1690static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1691{
1692 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1693}
1694
1695
1696static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1697 struct pid_namespace *ns)
1698{
1699 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1700}
1701
1702static inline pid_t task_session_vnr(struct task_struct *tsk)
1703{
1704 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1705}
1706
1707/* obsolete, do not use */
1708static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1709{
1710 return task_pgrp_nr_ns(tsk, &init_pid_ns);
1711}
1712
1713/**
1714 * pid_alive - check that a task structure is not stale
1715 * @p: Task structure to be checked.
1716 *
1717 * Test if a process is not yet dead (at most zombie state)
1718 * If pid_alive fails, then pointers within the task structure
1719 * can be stale and must not be dereferenced.
1720 */
1721static inline int pid_alive(struct task_struct *p)
1722{
1723 return p->pids[PIDTYPE_PID].pid != NULL;
1724}
1725
1726/**
1727 * is_global_init - check if a task structure is init
1728 * @tsk: Task structure to be checked.
1729 *
1730 * Check if a task structure is the first user space task the kernel created.
1731 */
1732static inline int is_global_init(struct task_struct *tsk)
1733{
1734 return tsk->pid == 1;
1735}
1736
1737/*
1738 * is_container_init:
1739 * check whether in the task is init in its own pid namespace.
1740 */
1741extern int is_container_init(struct task_struct *tsk);
1742
1743extern struct pid *cad_pid;
1744
1745extern void free_task(struct task_struct *tsk);
1746#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1747
1748extern void __put_task_struct(struct task_struct *t);
1749
1750static inline void put_task_struct(struct task_struct *t)
1751{
1752 if (atomic_dec_and_test(&t->usage))
1753 __put_task_struct(t);
1754}
1755
1756extern void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1757extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1758
1759/*
1760 * Per process flags
1761 */
1762#define PF_STARTING 0x00000002 /* being created */
1763#define PF_EXITING 0x00000004 /* getting shut down */
1764#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */
1765#define PF_VCPU 0x00000010 /* I'm a virtual CPU */
1766#define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */
1767#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
1768#define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */
1769#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
1770#define PF_DUMPCORE 0x00000200 /* dumped core */
1771#define PF_SIGNALED 0x00000400 /* killed by a signal */
1772#define PF_MEMALLOC 0x00000800 /* Allocating memory */
1773#define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */
1774#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
1775#define PF_FREEZING 0x00004000 /* freeze in progress. do not account to load */
1776#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
1777#define PF_FROZEN 0x00010000 /* frozen for system suspend */
1778#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
1779#define PF_KSWAPD 0x00040000 /* I am kswapd */
1780#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
1781#define PF_KTHREAD 0x00200000 /* I am a kernel thread */
1782#define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */
1783#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1784#define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */
1785#define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */
1786#define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpu */
1787#define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
1788#define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */
1789#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
1790#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */
1791#define PF_FREEZER_NOSIG 0x80000000 /* Freezer won't send signals to it */
1792
1793/*
1794 * Only the _current_ task can read/write to tsk->flags, but other
1795 * tasks can access tsk->flags in readonly mode for example
1796 * with tsk_used_math (like during threaded core dumping).
1797 * There is however an exception to this rule during ptrace
1798 * or during fork: the ptracer task is allowed to write to the
1799 * child->flags of its traced child (same goes for fork, the parent
1800 * can write to the child->flags), because we're guaranteed the
1801 * child is not running and in turn not changing child->flags
1802 * at the same time the parent does it.
1803 */
1804#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1805#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1806#define clear_used_math() clear_stopped_child_used_math(current)
1807#define set_used_math() set_stopped_child_used_math(current)
1808#define conditional_stopped_child_used_math(condition, child) \
1809 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1810#define conditional_used_math(condition) \
1811 conditional_stopped_child_used_math(condition, current)
1812#define copy_to_stopped_child_used_math(child) \
1813 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1814/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1815#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1816#define used_math() tsk_used_math(current)
1817
1818/*
1819 * task->jobctl flags
1820 */
1821#define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */
1822
1823#define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */
1824#define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */
1825#define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */
1826#define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */
1827#define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */
1828#define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */
1829#define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */
1830
1831#define JOBCTL_STOP_DEQUEUED (1 << JOBCTL_STOP_DEQUEUED_BIT)
1832#define JOBCTL_STOP_PENDING (1 << JOBCTL_STOP_PENDING_BIT)
1833#define JOBCTL_STOP_CONSUME (1 << JOBCTL_STOP_CONSUME_BIT)
1834#define JOBCTL_TRAP_STOP (1 << JOBCTL_TRAP_STOP_BIT)
1835#define JOBCTL_TRAP_NOTIFY (1 << JOBCTL_TRAP_NOTIFY_BIT)
1836#define JOBCTL_TRAPPING (1 << JOBCTL_TRAPPING_BIT)
1837#define JOBCTL_LISTENING (1 << JOBCTL_LISTENING_BIT)
1838
1839#define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY)
1840#define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK)
1841
1842extern bool task_set_jobctl_pending(struct task_struct *task,
1843 unsigned int mask);
1844extern void task_clear_jobctl_trapping(struct task_struct *task);
1845extern void task_clear_jobctl_pending(struct task_struct *task,
1846 unsigned int mask);
1847
1848#ifdef CONFIG_PREEMPT_RCU
1849
1850#define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */
1851#define RCU_READ_UNLOCK_BOOSTED (1 << 1) /* boosted while in RCU read-side. */
1852#define RCU_READ_UNLOCK_NEED_QS (1 << 2) /* RCU core needs CPU response. */
1853
1854static inline void rcu_copy_process(struct task_struct *p)
1855{
1856 p->rcu_read_lock_nesting = 0;
1857 p->rcu_read_unlock_special = 0;
1858#ifdef CONFIG_TREE_PREEMPT_RCU
1859 p->rcu_blocked_node = NULL;
1860#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1861#ifdef CONFIG_RCU_BOOST
1862 p->rcu_boost_mutex = NULL;
1863#endif /* #ifdef CONFIG_RCU_BOOST */
1864 INIT_LIST_HEAD(&p->rcu_node_entry);
1865}
1866
1867#else
1868
1869static inline void rcu_copy_process(struct task_struct *p)
1870{
1871}
1872
1873#endif
1874
1875#ifdef CONFIG_SMP
1876extern void do_set_cpus_allowed(struct task_struct *p,
1877 const struct cpumask *new_mask);
1878
1879extern int set_cpus_allowed_ptr(struct task_struct *p,
1880 const struct cpumask *new_mask);
1881#else
1882static inline void do_set_cpus_allowed(struct task_struct *p,
1883 const struct cpumask *new_mask)
1884{
1885}
1886static inline int set_cpus_allowed_ptr(struct task_struct *p,
1887 const struct cpumask *new_mask)
1888{
1889 if (!cpumask_test_cpu(0, new_mask))
1890 return -EINVAL;
1891 return 0;
1892}
1893#endif
1894
1895#ifndef CONFIG_CPUMASK_OFFSTACK
1896static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1897{
1898 return set_cpus_allowed_ptr(p, &new_mask);
1899}
1900#endif
1901
1902/*
1903 * Do not use outside of architecture code which knows its limitations.
1904 *
1905 * sched_clock() has no promise of monotonicity or bounded drift between
1906 * CPUs, use (which you should not) requires disabling IRQs.
1907 *
1908 * Please use one of the three interfaces below.
1909 */
1910extern unsigned long long notrace sched_clock(void);
1911/*
1912 * See the comment in kernel/sched_clock.c
1913 */
1914extern u64 cpu_clock(int cpu);
1915extern u64 local_clock(void);
1916extern u64 sched_clock_cpu(int cpu);
1917
1918
1919extern void sched_clock_init(void);
1920
1921#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1922static inline void sched_clock_tick(void)
1923{
1924}
1925
1926static inline void sched_clock_idle_sleep_event(void)
1927{
1928}
1929
1930static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
1931{
1932}
1933#else
1934/*
1935 * Architectures can set this to 1 if they have specified
1936 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
1937 * but then during bootup it turns out that sched_clock()
1938 * is reliable after all:
1939 */
1940extern int sched_clock_stable;
1941
1942extern void sched_clock_tick(void);
1943extern void sched_clock_idle_sleep_event(void);
1944extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1945#endif
1946
1947#ifdef CONFIG_IRQ_TIME_ACCOUNTING
1948/*
1949 * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
1950 * The reason for this explicit opt-in is not to have perf penalty with
1951 * slow sched_clocks.
1952 */
1953extern void enable_sched_clock_irqtime(void);
1954extern void disable_sched_clock_irqtime(void);
1955#else
1956static inline void enable_sched_clock_irqtime(void) {}
1957static inline void disable_sched_clock_irqtime(void) {}
1958#endif
1959
1960extern unsigned long long
1961task_sched_runtime(struct task_struct *task);
1962
1963/* sched_exec is called by processes performing an exec */
1964#ifdef CONFIG_SMP
1965extern void sched_exec(void);
1966#else
1967#define sched_exec() {}
1968#endif
1969
1970extern void sched_clock_idle_sleep_event(void);
1971extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1972
1973#ifdef CONFIG_HOTPLUG_CPU
1974extern void idle_task_exit(void);
1975#else
1976static inline void idle_task_exit(void) {}
1977#endif
1978
1979#if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1980extern void wake_up_idle_cpu(int cpu);
1981#else
1982static inline void wake_up_idle_cpu(int cpu) { }
1983#endif
1984
1985extern unsigned int sysctl_sched_latency;
1986extern unsigned int sysctl_sched_min_granularity;
1987extern unsigned int sysctl_sched_wakeup_granularity;
1988extern unsigned int sysctl_sched_child_runs_first;
1989
1990enum sched_tunable_scaling {
1991 SCHED_TUNABLESCALING_NONE,
1992 SCHED_TUNABLESCALING_LOG,
1993 SCHED_TUNABLESCALING_LINEAR,
1994 SCHED_TUNABLESCALING_END,
1995};
1996extern enum sched_tunable_scaling sysctl_sched_tunable_scaling;
1997
1998#ifdef CONFIG_SCHED_DEBUG
1999extern unsigned int sysctl_sched_migration_cost;
2000extern unsigned int sysctl_sched_nr_migrate;
2001extern unsigned int sysctl_sched_time_avg;
2002extern unsigned int sysctl_timer_migration;
2003extern unsigned int sysctl_sched_shares_window;
2004
2005int sched_proc_update_handler(struct ctl_table *table, int write,
2006 void __user *buffer, size_t *length,
2007 loff_t *ppos);
2008#endif
2009#ifdef CONFIG_SCHED_DEBUG
2010static inline unsigned int get_sysctl_timer_migration(void)
2011{
2012 return sysctl_timer_migration;
2013}
2014#else
2015static inline unsigned int get_sysctl_timer_migration(void)
2016{
2017 return 1;
2018}
2019#endif
2020extern unsigned int sysctl_sched_rt_period;
2021extern int sysctl_sched_rt_runtime;
2022
2023int sched_rt_handler(struct ctl_table *table, int write,
2024 void __user *buffer, size_t *lenp,
2025 loff_t *ppos);
2026
2027#ifdef CONFIG_SCHED_AUTOGROUP
2028extern unsigned int sysctl_sched_autogroup_enabled;
2029
2030extern void sched_autogroup_create_attach(struct task_struct *p);
2031extern void sched_autogroup_detach(struct task_struct *p);
2032extern void sched_autogroup_fork(struct signal_struct *sig);
2033extern void sched_autogroup_exit(struct signal_struct *sig);
2034#ifdef CONFIG_PROC_FS
2035extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
2036extern int proc_sched_autogroup_set_nice(struct task_struct *p, int *nice);
2037#endif
2038#else
2039static inline void sched_autogroup_create_attach(struct task_struct *p) { }
2040static inline void sched_autogroup_detach(struct task_struct *p) { }
2041static inline void sched_autogroup_fork(struct signal_struct *sig) { }
2042static inline void sched_autogroup_exit(struct signal_struct *sig) { }
2043#endif
2044
2045#ifdef CONFIG_CFS_BANDWIDTH
2046extern unsigned int sysctl_sched_cfs_bandwidth_slice;
2047#endif
2048
2049#ifdef CONFIG_RT_MUTEXES
2050extern int rt_mutex_getprio(struct task_struct *p);
2051extern void rt_mutex_setprio(struct task_struct *p, int prio);
2052extern void rt_mutex_adjust_pi(struct task_struct *p);
2053#else
2054static inline int rt_mutex_getprio(struct task_struct *p)
2055{
2056 return p->normal_prio;
2057}
2058# define rt_mutex_adjust_pi(p) do { } while (0)
2059#endif
2060
2061extern bool yield_to(struct task_struct *p, bool preempt);
2062extern void set_user_nice(struct task_struct *p, long nice);
2063extern int task_prio(const struct task_struct *p);
2064extern int task_nice(const struct task_struct *p);
2065extern int can_nice(const struct task_struct *p, const int nice);
2066extern int task_curr(const struct task_struct *p);
2067extern int idle_cpu(int cpu);
2068extern int sched_setscheduler(struct task_struct *, int,
2069 const struct sched_param *);
2070extern int sched_setscheduler_nocheck(struct task_struct *, int,
2071 const struct sched_param *);
2072extern struct task_struct *idle_task(int cpu);
2073extern struct task_struct *curr_task(int cpu);
2074extern void set_curr_task(int cpu, struct task_struct *p);
2075
2076void yield(void);
2077
2078/*
2079 * The default (Linux) execution domain.
2080 */
2081extern struct exec_domain default_exec_domain;
2082
2083union thread_union {
2084 struct thread_info thread_info;
2085 unsigned long stack[THREAD_SIZE/sizeof(long)];
2086};
2087
2088#ifndef __HAVE_ARCH_KSTACK_END
2089static inline int kstack_end(void *addr)
2090{
2091 /* Reliable end of stack detection:
2092 * Some APM bios versions misalign the stack
2093 */
2094 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
2095}
2096#endif
2097
2098extern union thread_union init_thread_union;
2099extern struct task_struct init_task;
2100
2101extern struct mm_struct init_mm;
2102
2103extern struct pid_namespace init_pid_ns;
2104
2105/*
2106 * find a task by one of its numerical ids
2107 *
2108 * find_task_by_pid_ns():
2109 * finds a task by its pid in the specified namespace
2110 * find_task_by_vpid():
2111 * finds a task by its virtual pid
2112 *
2113 * see also find_vpid() etc in include/linux/pid.h
2114 */
2115
2116extern struct task_struct *find_task_by_vpid(pid_t nr);
2117extern struct task_struct *find_task_by_pid_ns(pid_t nr,
2118 struct pid_namespace *ns);
2119
2120extern void __set_special_pids(struct pid *pid);
2121
2122/* per-UID process charging. */
2123extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
2124static inline struct user_struct *get_uid(struct user_struct *u)
2125{
2126 atomic_inc(&u->__count);
2127 return u;
2128}
2129extern void free_uid(struct user_struct *);
2130extern void release_uids(struct user_namespace *ns);
2131
2132#include <asm/current.h>
2133
2134extern void xtime_update(unsigned long ticks);
2135
2136extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2137extern int wake_up_process(struct task_struct *tsk);
2138extern void wake_up_new_task(struct task_struct *tsk);
2139#ifdef CONFIG_SMP
2140 extern void kick_process(struct task_struct *tsk);
2141#else
2142 static inline void kick_process(struct task_struct *tsk) { }
2143#endif
2144extern void sched_fork(struct task_struct *p);
2145extern void sched_dead(struct task_struct *p);
2146
2147extern void proc_caches_init(void);
2148extern void flush_signals(struct task_struct *);
2149extern void __flush_signals(struct task_struct *);
2150extern void ignore_signals(struct task_struct *);
2151extern void flush_signal_handlers(struct task_struct *, int force_default);
2152extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2153
2154static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
2155{
2156 unsigned long flags;
2157 int ret;
2158
2159 spin_lock_irqsave(&tsk->sighand->siglock, flags);
2160 ret = dequeue_signal(tsk, mask, info);
2161 spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
2162
2163 return ret;
2164}
2165
2166extern void block_all_signals(int (*notifier)(void *priv), void *priv,
2167 sigset_t *mask);
2168extern void unblock_all_signals(void);
2169extern void release_task(struct task_struct * p);
2170extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2171extern int force_sigsegv(int, struct task_struct *);
2172extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2173extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2174extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2175extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *,
2176 const struct cred *, u32);
2177extern int kill_pgrp(struct pid *pid, int sig, int priv);
2178extern int kill_pid(struct pid *pid, int sig, int priv);
2179extern int kill_proc_info(int, struct siginfo *, pid_t);
2180extern __must_check bool do_notify_parent(struct task_struct *, int);
2181extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2182extern void force_sig(int, struct task_struct *);
2183extern int send_sig(int, struct task_struct *, int);
2184extern int zap_other_threads(struct task_struct *p);
2185extern struct sigqueue *sigqueue_alloc(void);
2186extern void sigqueue_free(struct sigqueue *);
2187extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group);
2188extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2189extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
2190
2191static inline int kill_cad_pid(int sig, int priv)
2192{
2193 return kill_pid(cad_pid, sig, priv);
2194}
2195
2196/* These can be the second arg to send_sig_info/send_group_sig_info. */
2197#define SEND_SIG_NOINFO ((struct siginfo *) 0)
2198#define SEND_SIG_PRIV ((struct siginfo *) 1)
2199#define SEND_SIG_FORCED ((struct siginfo *) 2)
2200
2201/*
2202 * True if we are on the alternate signal stack.
2203 */
2204static inline int on_sig_stack(unsigned long sp)
2205{
2206#ifdef CONFIG_STACK_GROWSUP
2207 return sp >= current->sas_ss_sp &&
2208 sp - current->sas_ss_sp < current->sas_ss_size;
2209#else
2210 return sp > current->sas_ss_sp &&
2211 sp - current->sas_ss_sp <= current->sas_ss_size;
2212#endif
2213}
2214
2215static inline int sas_ss_flags(unsigned long sp)
2216{
2217 return (current->sas_ss_size == 0 ? SS_DISABLE
2218 : on_sig_stack(sp) ? SS_ONSTACK : 0);
2219}
2220
2221/*
2222 * Routines for handling mm_structs
2223 */
2224extern struct mm_struct * mm_alloc(void);
2225
2226/* mmdrop drops the mm and the page tables */
2227extern void __mmdrop(struct mm_struct *);
2228static inline void mmdrop(struct mm_struct * mm)
2229{
2230 if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2231 __mmdrop(mm);
2232}
2233
2234/* mmput gets rid of the mappings and all user-space */
2235extern void mmput(struct mm_struct *);
2236/* Grab a reference to a task's mm, if it is not already going away */
2237extern struct mm_struct *get_task_mm(struct task_struct *task);
2238/* Remove the current tasks stale references to the old mm_struct */
2239extern void mm_release(struct task_struct *, struct mm_struct *);
2240/* Allocate a new mm structure and copy contents from tsk->mm */
2241extern struct mm_struct *dup_mm(struct task_struct *tsk);
2242
2243extern int copy_thread(unsigned long, unsigned long, unsigned long,
2244 struct task_struct *, struct pt_regs *);
2245extern void flush_thread(void);
2246extern void exit_thread(void);
2247
2248extern void exit_files(struct task_struct *);
2249extern void __cleanup_sighand(struct sighand_struct *);
2250
2251extern void exit_itimers(struct signal_struct *);
2252extern void flush_itimer_signals(void);
2253
2254extern NORET_TYPE void do_group_exit(int);
2255
2256extern void daemonize(const char *, ...);
2257extern int allow_signal(int);
2258extern int disallow_signal(int);
2259
2260extern int do_execve(const char *,
2261 const char __user * const __user *,
2262 const char __user * const __user *, struct pt_regs *);
2263extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
2264struct task_struct *fork_idle(int);
2265
2266extern void set_task_comm(struct task_struct *tsk, char *from);
2267extern char *get_task_comm(char *to, struct task_struct *tsk);
2268
2269#ifdef CONFIG_SMP
2270void scheduler_ipi(void);
2271extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2272#else
2273static inline void scheduler_ipi(void) { }
2274static inline unsigned long wait_task_inactive(struct task_struct *p,
2275 long match_state)
2276{
2277 return 1;
2278}
2279#endif
2280
2281#define next_task(p) \
2282 list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2283
2284#define for_each_process(p) \
2285 for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2286
2287extern bool current_is_single_threaded(void);
2288
2289/*
2290 * Careful: do_each_thread/while_each_thread is a double loop so
2291 * 'break' will not work as expected - use goto instead.
2292 */
2293#define do_each_thread(g, t) \
2294 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2295
2296#define while_each_thread(g, t) \
2297 while ((t = next_thread(t)) != g)
2298
2299static inline int get_nr_threads(struct task_struct *tsk)
2300{
2301 return tsk->signal->nr_threads;
2302}
2303
2304static inline bool thread_group_leader(struct task_struct *p)
2305{
2306 return p->exit_signal >= 0;
2307}
2308
2309/* Do to the insanities of de_thread it is possible for a process
2310 * to have the pid of the thread group leader without actually being
2311 * the thread group leader. For iteration through the pids in proc
2312 * all we care about is that we have a task with the appropriate
2313 * pid, we don't actually care if we have the right task.
2314 */
2315static inline int has_group_leader_pid(struct task_struct *p)
2316{
2317 return p->pid == p->tgid;
2318}
2319
2320static inline
2321int same_thread_group(struct task_struct *p1, struct task_struct *p2)
2322{
2323 return p1->tgid == p2->tgid;
2324}
2325
2326static inline struct task_struct *next_thread(const struct task_struct *p)
2327{
2328 return list_entry_rcu(p->thread_group.next,
2329 struct task_struct, thread_group);
2330}
2331
2332static inline int thread_group_empty(struct task_struct *p)
2333{
2334 return list_empty(&p->thread_group);
2335}
2336
2337#define delay_group_leader(p) \
2338 (thread_group_leader(p) && !thread_group_empty(p))
2339
2340/*
2341 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2342 * subscriptions and synchronises with wait4(). Also used in procfs. Also
2343 * pins the final release of task.io_context. Also protects ->cpuset and
2344 * ->cgroup.subsys[].
2345 *
2346 * Nests both inside and outside of read_lock(&tasklist_lock).
2347 * It must not be nested with write_lock_irq(&tasklist_lock),
2348 * neither inside nor outside.
2349 */
2350static inline void task_lock(struct task_struct *p)
2351{
2352 spin_lock(&p->alloc_lock);
2353}
2354
2355static inline void task_unlock(struct task_struct *p)
2356{
2357 spin_unlock(&p->alloc_lock);
2358}
2359
2360extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2361 unsigned long *flags);
2362
2363#define lock_task_sighand(tsk, flags) \
2364({ struct sighand_struct *__ss; \
2365 __cond_lock(&(tsk)->sighand->siglock, \
2366 (__ss = __lock_task_sighand(tsk, flags))); \
2367 __ss; \
2368}) \
2369
2370static inline void unlock_task_sighand(struct task_struct *tsk,
2371 unsigned long *flags)
2372{
2373 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2374}
2375
2376/* See the declaration of threadgroup_fork_lock in signal_struct. */
2377#ifdef CONFIG_CGROUPS
2378static inline void threadgroup_fork_read_lock(struct task_struct *tsk)
2379{
2380 down_read(&tsk->signal->threadgroup_fork_lock);
2381}
2382static inline void threadgroup_fork_read_unlock(struct task_struct *tsk)
2383{
2384 up_read(&tsk->signal->threadgroup_fork_lock);
2385}
2386static inline void threadgroup_fork_write_lock(struct task_struct *tsk)
2387{
2388 down_write(&tsk->signal->threadgroup_fork_lock);
2389}
2390static inline void threadgroup_fork_write_unlock(struct task_struct *tsk)
2391{
2392 up_write(&tsk->signal->threadgroup_fork_lock);
2393}
2394#else
2395static inline void threadgroup_fork_read_lock(struct task_struct *tsk) {}
2396static inline void threadgroup_fork_read_unlock(struct task_struct *tsk) {}
2397static inline void threadgroup_fork_write_lock(struct task_struct *tsk) {}
2398static inline void threadgroup_fork_write_unlock(struct task_struct *tsk) {}
2399#endif
2400
2401#ifndef __HAVE_THREAD_FUNCTIONS
2402
2403#define task_thread_info(task) ((struct thread_info *)(task)->stack)
2404#define task_stack_page(task) ((task)->stack)
2405
2406static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2407{
2408 *task_thread_info(p) = *task_thread_info(org);
2409 task_thread_info(p)->task = p;
2410}
2411
2412static inline unsigned long *end_of_stack(struct task_struct *p)
2413{
2414 return (unsigned long *)(task_thread_info(p) + 1);
2415}
2416
2417#endif
2418
2419static inline int object_is_on_stack(void *obj)
2420{
2421 void *stack = task_stack_page(current);
2422
2423 return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2424}
2425
2426extern void thread_info_cache_init(void);
2427
2428#ifdef CONFIG_DEBUG_STACK_USAGE
2429static inline unsigned long stack_not_used(struct task_struct *p)
2430{
2431 unsigned long *n = end_of_stack(p);
2432
2433 do { /* Skip over canary */
2434 n++;
2435 } while (!*n);
2436
2437 return (unsigned long)n - (unsigned long)end_of_stack(p);
2438}
2439#endif
2440
2441/* set thread flags in other task's structures
2442 * - see asm/thread_info.h for TIF_xxxx flags available
2443 */
2444static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2445{
2446 set_ti_thread_flag(task_thread_info(tsk), flag);
2447}
2448
2449static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2450{
2451 clear_ti_thread_flag(task_thread_info(tsk), flag);
2452}
2453
2454static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2455{
2456 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2457}
2458
2459static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2460{
2461 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2462}
2463
2464static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2465{
2466 return test_ti_thread_flag(task_thread_info(tsk), flag);
2467}
2468
2469static inline void set_tsk_need_resched(struct task_struct *tsk)
2470{
2471 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2472}
2473
2474static inline void clear_tsk_need_resched(struct task_struct *tsk)
2475{
2476 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2477}
2478
2479static inline int test_tsk_need_resched(struct task_struct *tsk)
2480{
2481 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2482}
2483
2484static inline int restart_syscall(void)
2485{
2486 set_tsk_thread_flag(current, TIF_SIGPENDING);
2487 return -ERESTARTNOINTR;
2488}
2489
2490static inline int signal_pending(struct task_struct *p)
2491{
2492 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2493}
2494
2495static inline int __fatal_signal_pending(struct task_struct *p)
2496{
2497 return unlikely(sigismember(&p->pending.signal, SIGKILL));
2498}
2499
2500static inline int fatal_signal_pending(struct task_struct *p)
2501{
2502 return signal_pending(p) && __fatal_signal_pending(p);
2503}
2504
2505static inline int signal_pending_state(long state, struct task_struct *p)
2506{
2507 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2508 return 0;
2509 if (!signal_pending(p))
2510 return 0;
2511
2512 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2513}
2514
2515static inline int need_resched(void)
2516{
2517 return unlikely(test_thread_flag(TIF_NEED_RESCHED));
2518}
2519
2520/*
2521 * cond_resched() and cond_resched_lock(): latency reduction via
2522 * explicit rescheduling in places that are safe. The return
2523 * value indicates whether a reschedule was done in fact.
2524 * cond_resched_lock() will drop the spinlock before scheduling,
2525 * cond_resched_softirq() will enable bhs before scheduling.
2526 */
2527extern int _cond_resched(void);
2528
2529#define cond_resched() ({ \
2530 __might_sleep(__FILE__, __LINE__, 0); \
2531 _cond_resched(); \
2532})
2533
2534extern int __cond_resched_lock(spinlock_t *lock);
2535
2536#ifdef CONFIG_PREEMPT_COUNT
2537#define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET
2538#else
2539#define PREEMPT_LOCK_OFFSET 0
2540#endif
2541
2542#define cond_resched_lock(lock) ({ \
2543 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \
2544 __cond_resched_lock(lock); \
2545})
2546
2547extern int __cond_resched_softirq(void);
2548
2549#define cond_resched_softirq() ({ \
2550 __might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \
2551 __cond_resched_softirq(); \
2552})
2553
2554/*
2555 * Does a critical section need to be broken due to another
2556 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2557 * but a general need for low latency)
2558 */
2559static inline int spin_needbreak(spinlock_t *lock)
2560{
2561#ifdef CONFIG_PREEMPT
2562 return spin_is_contended(lock);
2563#else
2564 return 0;
2565#endif
2566}
2567
2568/*
2569 * Thread group CPU time accounting.
2570 */
2571void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2572void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2573
2574static inline void thread_group_cputime_init(struct signal_struct *sig)
2575{
2576 raw_spin_lock_init(&sig->cputimer.lock);
2577}
2578
2579/*
2580 * Reevaluate whether the task has signals pending delivery.
2581 * Wake the task if so.
2582 * This is required every time the blocked sigset_t changes.
2583 * callers must hold sighand->siglock.
2584 */
2585extern void recalc_sigpending_and_wake(struct task_struct *t);
2586extern void recalc_sigpending(void);
2587
2588extern void signal_wake_up(struct task_struct *t, int resume_stopped);
2589
2590/*
2591 * Wrappers for p->thread_info->cpu access. No-op on UP.
2592 */
2593#ifdef CONFIG_SMP
2594
2595static inline unsigned int task_cpu(const struct task_struct *p)
2596{
2597 return task_thread_info(p)->cpu;
2598}
2599
2600extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2601
2602#else
2603
2604static inline unsigned int task_cpu(const struct task_struct *p)
2605{
2606 return 0;
2607}
2608
2609static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2610{
2611}
2612
2613#endif /* CONFIG_SMP */
2614
2615extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2616extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2617
2618extern void normalize_rt_tasks(void);
2619
2620#ifdef CONFIG_CGROUP_SCHED
2621
2622extern struct task_group root_task_group;
2623
2624extern struct task_group *sched_create_group(struct task_group *parent);
2625extern void sched_destroy_group(struct task_group *tg);
2626extern void sched_move_task(struct task_struct *tsk);
2627#ifdef CONFIG_FAIR_GROUP_SCHED
2628extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2629extern unsigned long sched_group_shares(struct task_group *tg);
2630#endif
2631#ifdef CONFIG_RT_GROUP_SCHED
2632extern int sched_group_set_rt_runtime(struct task_group *tg,
2633 long rt_runtime_us);
2634extern long sched_group_rt_runtime(struct task_group *tg);
2635extern int sched_group_set_rt_period(struct task_group *tg,
2636 long rt_period_us);
2637extern long sched_group_rt_period(struct task_group *tg);
2638extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
2639#endif
2640#endif
2641
2642extern int task_can_switch_user(struct user_struct *up,
2643 struct task_struct *tsk);
2644
2645#ifdef CONFIG_TASK_XACCT
2646static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2647{
2648 tsk->ioac.rchar += amt;
2649}
2650
2651static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2652{
2653 tsk->ioac.wchar += amt;
2654}
2655
2656static inline void inc_syscr(struct task_struct *tsk)
2657{
2658 tsk->ioac.syscr++;
2659}
2660
2661static inline void inc_syscw(struct task_struct *tsk)
2662{
2663 tsk->ioac.syscw++;
2664}
2665#else
2666static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2667{
2668}
2669
2670static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2671{
2672}
2673
2674static inline void inc_syscr(struct task_struct *tsk)
2675{
2676}
2677
2678static inline void inc_syscw(struct task_struct *tsk)
2679{
2680}
2681#endif
2682
2683#ifndef TASK_SIZE_OF
2684#define TASK_SIZE_OF(tsk) TASK_SIZE
2685#endif
2686
2687#ifdef CONFIG_MM_OWNER
2688extern void mm_update_next_owner(struct mm_struct *mm);
2689extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2690#else
2691static inline void mm_update_next_owner(struct mm_struct *mm)
2692{
2693}
2694
2695static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2696{
2697}
2698#endif /* CONFIG_MM_OWNER */
2699
2700static inline unsigned long task_rlimit(const struct task_struct *tsk,
2701 unsigned int limit)
2702{
2703 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur);
2704}
2705
2706static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
2707 unsigned int limit)
2708{
2709 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max);
2710}
2711
2712static inline unsigned long rlimit(unsigned int limit)
2713{
2714 return task_rlimit(current, limit);
2715}
2716
2717static inline unsigned long rlimit_max(unsigned int limit)
2718{
2719 return task_rlimit_max(current, limit);
2720}
2721
2722#endif /* __KERNEL__ */
2723
2724#endif