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
94#include <asm/processor.h>
95
96struct exec_domain;
97struct futex_pi_state;
98struct robust_list_head;
99struct bio_list;
100struct fs_struct;
101struct perf_event_context;
102struct blk_plug;
103
104/*
105 * List of flags we want to share for kernel threads,
106 * if only because they are not used by them anyway.
107 */
108#define CLONE_KERNEL (CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
109
110/*
111 * These are the constant used to fake the fixed-point load-average
112 * counting. Some notes:
113 * - 11 bit fractions expand to 22 bits by the multiplies: this gives
114 * a load-average precision of 10 bits integer + 11 bits fractional
115 * - if you want to count load-averages more often, you need more
116 * precision, or rounding will get you. With 2-second counting freq,
117 * the EXP_n values would be 1981, 2034 and 2043 if still using only
118 * 11 bit fractions.
119 */
120extern unsigned long avenrun[]; /* Load averages */
121extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
122
123#define FSHIFT 11 /* nr of bits of precision */
124#define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
125#define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */
126#define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
127#define EXP_5 2014 /* 1/exp(5sec/5min) */
128#define EXP_15 2037 /* 1/exp(5sec/15min) */
129
130#define CALC_LOAD(load,exp,n) \
131 load *= exp; \
132 load += n*(FIXED_1-exp); \
133 load >>= FSHIFT;
134
135extern unsigned long total_forks;
136extern int nr_threads;
137DECLARE_PER_CPU(unsigned long, process_counts);
138extern int nr_processes(void);
139extern unsigned long nr_running(void);
140extern unsigned long nr_uninterruptible(void);
141extern unsigned long nr_iowait(void);
142extern unsigned long nr_iowait_cpu(int cpu);
143extern unsigned long this_cpu_load(void);
144
145
146extern void calc_global_load(unsigned long ticks);
147
148extern unsigned long get_parent_ip(unsigned long addr);
149
150struct seq_file;
151struct cfs_rq;
152struct task_group;
153#ifdef CONFIG_SCHED_DEBUG
154extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
155extern void proc_sched_set_task(struct task_struct *p);
156extern void
157print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
158#else
159static inline void
160proc_sched_show_task(struct task_struct *p, struct seq_file *m)
161{
162}
163static inline void proc_sched_set_task(struct task_struct *p)
164{
165}
166static inline void
167print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
168{
169}
170#endif
171
172/*
173 * Task state bitmask. NOTE! These bits are also
174 * encoded in fs/proc/array.c: get_task_state().
175 *
176 * We have two separate sets of flags: task->state
177 * is about runnability, while task->exit_state are
178 * about the task exiting. Confusing, but this way
179 * modifying one set can't modify the other one by
180 * mistake.
181 */
182#define TASK_RUNNING 0
183#define TASK_INTERRUPTIBLE 1
184#define TASK_UNINTERRUPTIBLE 2
185#define __TASK_STOPPED 4
186#define __TASK_TRACED 8
187/* in tsk->exit_state */
188#define EXIT_ZOMBIE 16
189#define EXIT_DEAD 32
190/* in tsk->state again */
191#define TASK_DEAD 64
192#define TASK_WAKEKILL 128
193#define TASK_WAKING 256
194#define TASK_STATE_MAX 512
195
196#define TASK_STATE_TO_CHAR_STR "RSDTtZXxKW"
197
198extern char ___assert_task_state[1 - 2*!!(
199 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
200
201/* Convenience macros for the sake of set_task_state */
202#define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
203#define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
204#define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED)
205
206/* Convenience macros for the sake of wake_up */
207#define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
208#define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
209
210/* get_task_state() */
211#define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \
212 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
213 __TASK_TRACED)
214
215#define task_is_traced(task) ((task->state & __TASK_TRACED) != 0)
216#define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0)
217#define task_is_dead(task) ((task)->exit_state != 0)
218#define task_is_stopped_or_traced(task) \
219 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
220#define task_contributes_to_load(task) \
221 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
222 (task->flags & PF_FREEZING) == 0)
223
224#define __set_task_state(tsk, state_value) \
225 do { (tsk)->state = (state_value); } while (0)
226#define set_task_state(tsk, state_value) \
227 set_mb((tsk)->state, (state_value))
228
229/*
230 * set_current_state() includes a barrier so that the write of current->state
231 * is correctly serialised wrt the caller's subsequent test of whether to
232 * actually sleep:
233 *
234 * set_current_state(TASK_UNINTERRUPTIBLE);
235 * if (do_i_need_to_sleep())
236 * schedule();
237 *
238 * If the caller does not need such serialisation then use __set_current_state()
239 */
240#define __set_current_state(state_value) \
241 do { current->state = (state_value); } while (0)
242#define set_current_state(state_value) \
243 set_mb(current->state, (state_value))
244
245/* Task command name length */
246#define TASK_COMM_LEN 16
247
248#include <linux/spinlock.h>
249
250/*
251 * This serializes "schedule()" and also protects
252 * the run-queue from deletions/modifications (but
253 * _adding_ to the beginning of the run-queue has
254 * a separate lock).
255 */
256extern rwlock_t tasklist_lock;
257extern spinlock_t mmlist_lock;
258
259struct task_struct;
260
261#ifdef CONFIG_PROVE_RCU
262extern int lockdep_tasklist_lock_is_held(void);
263#endif /* #ifdef CONFIG_PROVE_RCU */
264
265extern void sched_init(void);
266extern void sched_init_smp(void);
267extern asmlinkage void schedule_tail(struct task_struct *prev);
268extern void init_idle(struct task_struct *idle, int cpu);
269extern void init_idle_bootup_task(struct task_struct *idle);
270
271extern int runqueue_is_locked(int cpu);
272
273extern cpumask_var_t nohz_cpu_mask;
274#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
275extern void select_nohz_load_balancer(int stop_tick);
276extern int get_nohz_timer_target(void);
277#else
278static inline void select_nohz_load_balancer(int stop_tick) { }
279#endif
280
281/*
282 * Only dump TASK_* tasks. (0 for all tasks)
283 */
284extern void show_state_filter(unsigned long state_filter);
285
286static inline void show_state(void)
287{
288 show_state_filter(0);
289}
290
291extern void show_regs(struct pt_regs *);
292
293/*
294 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
295 * task), SP is the stack pointer of the first frame that should be shown in the back
296 * trace (or NULL if the entire call-chain of the task should be shown).
297 */
298extern void show_stack(struct task_struct *task, unsigned long *sp);
299
300void io_schedule(void);
301long io_schedule_timeout(long timeout);
302
303extern void cpu_init (void);
304extern void trap_init(void);
305extern void update_process_times(int user);
306extern void scheduler_tick(void);
307
308extern void sched_show_task(struct task_struct *p);
309
310#ifdef CONFIG_LOCKUP_DETECTOR
311extern void touch_softlockup_watchdog(void);
312extern void touch_softlockup_watchdog_sync(void);
313extern void touch_all_softlockup_watchdogs(void);
314extern int proc_dowatchdog_thresh(struct ctl_table *table, int write,
315 void __user *buffer,
316 size_t *lenp, loff_t *ppos);
317extern unsigned int softlockup_panic;
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 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 task_struct *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#if defined(CONFIG_RCU_BOOST) && defined(CONFIG_TREE_PREEMPT_RCU)
1264 int rcu_boosted;
1265#endif /* #if defined(CONFIG_RCU_BOOST) && defined(CONFIG_TREE_PREEMPT_RCU) */
1266 struct list_head rcu_node_entry;
1267#endif /* #ifdef CONFIG_PREEMPT_RCU */
1268#ifdef CONFIG_TREE_PREEMPT_RCU
1269 struct rcu_node *rcu_blocked_node;
1270#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1271#ifdef CONFIG_RCU_BOOST
1272 struct rt_mutex *rcu_boost_mutex;
1273#endif /* #ifdef CONFIG_RCU_BOOST */
1274
1275#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1276 struct sched_info sched_info;
1277#endif
1278
1279 struct list_head tasks;
1280#ifdef CONFIG_SMP
1281 struct plist_node pushable_tasks;
1282#endif
1283
1284 struct mm_struct *mm, *active_mm;
1285#ifdef CONFIG_COMPAT_BRK
1286 unsigned brk_randomized:1;
1287#endif
1288#if defined(SPLIT_RSS_COUNTING)
1289 struct task_rss_stat rss_stat;
1290#endif
1291/* task state */
1292 int exit_state;
1293 int exit_code, exit_signal;
1294 int pdeath_signal; /* The signal sent when the parent dies */
1295 unsigned int group_stop; /* GROUP_STOP_*, siglock protected */
1296 /* ??? */
1297 unsigned int personality;
1298 unsigned did_exec:1;
1299 unsigned in_execve:1; /* Tell the LSMs that the process is doing an
1300 * execve */
1301 unsigned in_iowait:1;
1302
1303
1304 /* Revert to default priority/policy when forking */
1305 unsigned sched_reset_on_fork:1;
1306 unsigned sched_contributes_to_load:1;
1307
1308 pid_t pid;
1309 pid_t tgid;
1310
1311#ifdef CONFIG_CC_STACKPROTECTOR
1312 /* Canary value for the -fstack-protector gcc feature */
1313 unsigned long stack_canary;
1314#endif
1315
1316 /*
1317 * pointers to (original) parent process, youngest child, younger sibling,
1318 * older sibling, respectively. (p->father can be replaced with
1319 * p->real_parent->pid)
1320 */
1321 struct task_struct *real_parent; /* real parent process */
1322 struct task_struct *parent; /* recipient of SIGCHLD, wait4() reports */
1323 /*
1324 * children/sibling forms the list of my natural children
1325 */
1326 struct list_head children; /* list of my children */
1327 struct list_head sibling; /* linkage in my parent's children list */
1328 struct task_struct *group_leader; /* threadgroup leader */
1329
1330 /*
1331 * ptraced is the list of tasks this task is using ptrace on.
1332 * This includes both natural children and PTRACE_ATTACH targets.
1333 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1334 */
1335 struct list_head ptraced;
1336 struct list_head ptrace_entry;
1337
1338 /* PID/PID hash table linkage. */
1339 struct pid_link pids[PIDTYPE_MAX];
1340 struct list_head thread_group;
1341
1342 struct completion *vfork_done; /* for vfork() */
1343 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
1344 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
1345
1346 cputime_t utime, stime, utimescaled, stimescaled;
1347 cputime_t gtime;
1348#ifndef CONFIG_VIRT_CPU_ACCOUNTING
1349 cputime_t prev_utime, prev_stime;
1350#endif
1351 unsigned long nvcsw, nivcsw; /* context switch counts */
1352 struct timespec start_time; /* monotonic time */
1353 struct timespec real_start_time; /* boot based time */
1354/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1355 unsigned long min_flt, maj_flt;
1356
1357 struct task_cputime cputime_expires;
1358 struct list_head cpu_timers[3];
1359
1360/* process credentials */
1361 const struct cred __rcu *real_cred; /* objective and real subjective task
1362 * credentials (COW) */
1363 const struct cred __rcu *cred; /* effective (overridable) subjective task
1364 * credentials (COW) */
1365 struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */
1366
1367 char comm[TASK_COMM_LEN]; /* executable name excluding path
1368 - access with [gs]et_task_comm (which lock
1369 it with task_lock())
1370 - initialized normally by setup_new_exec */
1371/* file system info */
1372 int link_count, total_link_count;
1373#ifdef CONFIG_SYSVIPC
1374/* ipc stuff */
1375 struct sysv_sem sysvsem;
1376#endif
1377#ifdef CONFIG_DETECT_HUNG_TASK
1378/* hung task detection */
1379 unsigned long last_switch_count;
1380#endif
1381/* CPU-specific state of this task */
1382 struct thread_struct thread;
1383/* filesystem information */
1384 struct fs_struct *fs;
1385/* open file information */
1386 struct files_struct *files;
1387/* namespaces */
1388 struct nsproxy *nsproxy;
1389/* signal handlers */
1390 struct signal_struct *signal;
1391 struct sighand_struct *sighand;
1392
1393 sigset_t blocked, real_blocked;
1394 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
1395 struct sigpending pending;
1396
1397 unsigned long sas_ss_sp;
1398 size_t sas_ss_size;
1399 int (*notifier)(void *priv);
1400 void *notifier_data;
1401 sigset_t *notifier_mask;
1402 struct audit_context *audit_context;
1403#ifdef CONFIG_AUDITSYSCALL
1404 uid_t loginuid;
1405 unsigned int sessionid;
1406#endif
1407 seccomp_t seccomp;
1408
1409/* Thread group tracking */
1410 u32 parent_exec_id;
1411 u32 self_exec_id;
1412/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1413 * mempolicy */
1414 spinlock_t alloc_lock;
1415
1416#ifdef CONFIG_GENERIC_HARDIRQS
1417 /* IRQ handler threads */
1418 struct irqaction *irqaction;
1419#endif
1420
1421 /* Protection of the PI data structures: */
1422 raw_spinlock_t pi_lock;
1423
1424#ifdef CONFIG_RT_MUTEXES
1425 /* PI waiters blocked on a rt_mutex held by this task */
1426 struct plist_head pi_waiters;
1427 /* Deadlock detection and priority inheritance handling */
1428 struct rt_mutex_waiter *pi_blocked_on;
1429#endif
1430
1431#ifdef CONFIG_DEBUG_MUTEXES
1432 /* mutex deadlock detection */
1433 struct mutex_waiter *blocked_on;
1434#endif
1435#ifdef CONFIG_TRACE_IRQFLAGS
1436 unsigned int irq_events;
1437 unsigned long hardirq_enable_ip;
1438 unsigned long hardirq_disable_ip;
1439 unsigned int hardirq_enable_event;
1440 unsigned int hardirq_disable_event;
1441 int hardirqs_enabled;
1442 int hardirq_context;
1443 unsigned long softirq_disable_ip;
1444 unsigned long softirq_enable_ip;
1445 unsigned int softirq_disable_event;
1446 unsigned int softirq_enable_event;
1447 int softirqs_enabled;
1448 int softirq_context;
1449#endif
1450#ifdef CONFIG_LOCKDEP
1451# define MAX_LOCK_DEPTH 48UL
1452 u64 curr_chain_key;
1453 int lockdep_depth;
1454 unsigned int lockdep_recursion;
1455 struct held_lock held_locks[MAX_LOCK_DEPTH];
1456 gfp_t lockdep_reclaim_gfp;
1457#endif
1458
1459/* journalling filesystem info */
1460 void *journal_info;
1461
1462/* stacked block device info */
1463 struct bio_list *bio_list;
1464
1465#ifdef CONFIG_BLOCK
1466/* stack plugging */
1467 struct blk_plug *plug;
1468#endif
1469
1470/* VM state */
1471 struct reclaim_state *reclaim_state;
1472
1473 struct backing_dev_info *backing_dev_info;
1474
1475 struct io_context *io_context;
1476
1477 unsigned long ptrace_message;
1478 siginfo_t *last_siginfo; /* For ptrace use. */
1479 struct task_io_accounting ioac;
1480#if defined(CONFIG_TASK_XACCT)
1481 u64 acct_rss_mem1; /* accumulated rss usage */
1482 u64 acct_vm_mem1; /* accumulated virtual memory usage */
1483 cputime_t acct_timexpd; /* stime + utime since last update */
1484#endif
1485#ifdef CONFIG_CPUSETS
1486 nodemask_t mems_allowed; /* Protected by alloc_lock */
1487 int mems_allowed_change_disable;
1488 int cpuset_mem_spread_rotor;
1489 int cpuset_slab_spread_rotor;
1490#endif
1491#ifdef CONFIG_CGROUPS
1492 /* Control Group info protected by css_set_lock */
1493 struct css_set __rcu *cgroups;
1494 /* cg_list protected by css_set_lock and tsk->alloc_lock */
1495 struct list_head cg_list;
1496#endif
1497#ifdef CONFIG_FUTEX
1498 struct robust_list_head __user *robust_list;
1499#ifdef CONFIG_COMPAT
1500 struct compat_robust_list_head __user *compat_robust_list;
1501#endif
1502 struct list_head pi_state_list;
1503 struct futex_pi_state *pi_state_cache;
1504#endif
1505#ifdef CONFIG_PERF_EVENTS
1506 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1507 struct mutex perf_event_mutex;
1508 struct list_head perf_event_list;
1509#endif
1510#ifdef CONFIG_NUMA
1511 struct mempolicy *mempolicy; /* Protected by alloc_lock */
1512 short il_next;
1513 short pref_node_fork;
1514#endif
1515 atomic_t fs_excl; /* holding fs exclusive resources */
1516 struct rcu_head rcu;
1517
1518 /*
1519 * cache last used pipe for splice
1520 */
1521 struct pipe_inode_info *splice_pipe;
1522#ifdef CONFIG_TASK_DELAY_ACCT
1523 struct task_delay_info *delays;
1524#endif
1525#ifdef CONFIG_FAULT_INJECTION
1526 int make_it_fail;
1527#endif
1528 struct prop_local_single dirties;
1529#ifdef CONFIG_LATENCYTOP
1530 int latency_record_count;
1531 struct latency_record latency_record[LT_SAVECOUNT];
1532#endif
1533 /*
1534 * time slack values; these are used to round up poll() and
1535 * select() etc timeout values. These are in nanoseconds.
1536 */
1537 unsigned long timer_slack_ns;
1538 unsigned long default_timer_slack_ns;
1539
1540 struct list_head *scm_work_list;
1541#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1542 /* Index of current stored address in ret_stack */
1543 int curr_ret_stack;
1544 /* Stack of return addresses for return function tracing */
1545 struct ftrace_ret_stack *ret_stack;
1546 /* time stamp for last schedule */
1547 unsigned long long ftrace_timestamp;
1548 /*
1549 * Number of functions that haven't been traced
1550 * because of depth overrun.
1551 */
1552 atomic_t trace_overrun;
1553 /* Pause for the tracing */
1554 atomic_t tracing_graph_pause;
1555#endif
1556#ifdef CONFIG_TRACING
1557 /* state flags for use by tracers */
1558 unsigned long trace;
1559 /* bitmask and counter of trace recursion */
1560 unsigned long trace_recursion;
1561#endif /* CONFIG_TRACING */
1562#ifdef CONFIG_CGROUP_MEM_RES_CTLR /* memcg uses this to do batch job */
1563 struct memcg_batch_info {
1564 int do_batch; /* incremented when batch uncharge started */
1565 struct mem_cgroup *memcg; /* target memcg of uncharge */
1566 unsigned long nr_pages; /* uncharged usage */
1567 unsigned long memsw_nr_pages; /* uncharged mem+swap usage */
1568 } memcg_batch;
1569#endif
1570#ifdef CONFIG_HAVE_HW_BREAKPOINT
1571 atomic_t ptrace_bp_refcnt;
1572#endif
1573};
1574
1575/* Future-safe accessor for struct task_struct's cpus_allowed. */
1576#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1577
1578/*
1579 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1580 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1581 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1582 * values are inverted: lower p->prio value means higher priority.
1583 *
1584 * The MAX_USER_RT_PRIO value allows the actual maximum
1585 * RT priority to be separate from the value exported to
1586 * user-space. This allows kernel threads to set their
1587 * priority to a value higher than any user task. Note:
1588 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1589 */
1590
1591#define MAX_USER_RT_PRIO 100
1592#define MAX_RT_PRIO MAX_USER_RT_PRIO
1593
1594#define MAX_PRIO (MAX_RT_PRIO + 40)
1595#define DEFAULT_PRIO (MAX_RT_PRIO + 20)
1596
1597static inline int rt_prio(int prio)
1598{
1599 if (unlikely(prio < MAX_RT_PRIO))
1600 return 1;
1601 return 0;
1602}
1603
1604static inline int rt_task(struct task_struct *p)
1605{
1606 return rt_prio(p->prio);
1607}
1608
1609static inline struct pid *task_pid(struct task_struct *task)
1610{
1611 return task->pids[PIDTYPE_PID].pid;
1612}
1613
1614static inline struct pid *task_tgid(struct task_struct *task)
1615{
1616 return task->group_leader->pids[PIDTYPE_PID].pid;
1617}
1618
1619/*
1620 * Without tasklist or rcu lock it is not safe to dereference
1621 * the result of task_pgrp/task_session even if task == current,
1622 * we can race with another thread doing sys_setsid/sys_setpgid.
1623 */
1624static inline struct pid *task_pgrp(struct task_struct *task)
1625{
1626 return task->group_leader->pids[PIDTYPE_PGID].pid;
1627}
1628
1629static inline struct pid *task_session(struct task_struct *task)
1630{
1631 return task->group_leader->pids[PIDTYPE_SID].pid;
1632}
1633
1634struct pid_namespace;
1635
1636/*
1637 * the helpers to get the task's different pids as they are seen
1638 * from various namespaces
1639 *
1640 * task_xid_nr() : global id, i.e. the id seen from the init namespace;
1641 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of
1642 * current.
1643 * task_xid_nr_ns() : id seen from the ns specified;
1644 *
1645 * set_task_vxid() : assigns a virtual id to a task;
1646 *
1647 * see also pid_nr() etc in include/linux/pid.h
1648 */
1649pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1650 struct pid_namespace *ns);
1651
1652static inline pid_t task_pid_nr(struct task_struct *tsk)
1653{
1654 return tsk->pid;
1655}
1656
1657static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1658 struct pid_namespace *ns)
1659{
1660 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1661}
1662
1663static inline pid_t task_pid_vnr(struct task_struct *tsk)
1664{
1665 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1666}
1667
1668
1669static inline pid_t task_tgid_nr(struct task_struct *tsk)
1670{
1671 return tsk->tgid;
1672}
1673
1674pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1675
1676static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1677{
1678 return pid_vnr(task_tgid(tsk));
1679}
1680
1681
1682static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1683 struct pid_namespace *ns)
1684{
1685 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1686}
1687
1688static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1689{
1690 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1691}
1692
1693
1694static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1695 struct pid_namespace *ns)
1696{
1697 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1698}
1699
1700static inline pid_t task_session_vnr(struct task_struct *tsk)
1701{
1702 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1703}
1704
1705/* obsolete, do not use */
1706static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1707{
1708 return task_pgrp_nr_ns(tsk, &init_pid_ns);
1709}
1710
1711/**
1712 * pid_alive - check that a task structure is not stale
1713 * @p: Task structure to be checked.
1714 *
1715 * Test if a process is not yet dead (at most zombie state)
1716 * If pid_alive fails, then pointers within the task structure
1717 * can be stale and must not be dereferenced.
1718 */
1719static inline int pid_alive(struct task_struct *p)
1720{
1721 return p->pids[PIDTYPE_PID].pid != NULL;
1722}
1723
1724/**
1725 * is_global_init - check if a task structure is init
1726 * @tsk: Task structure to be checked.
1727 *
1728 * Check if a task structure is the first user space task the kernel created.
1729 */
1730static inline int is_global_init(struct task_struct *tsk)
1731{
1732 return tsk->pid == 1;
1733}
1734
1735/*
1736 * is_container_init:
1737 * check whether in the task is init in its own pid namespace.
1738 */
1739extern int is_container_init(struct task_struct *tsk);
1740
1741extern struct pid *cad_pid;
1742
1743extern void free_task(struct task_struct *tsk);
1744#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1745
1746extern void __put_task_struct(struct task_struct *t);
1747
1748static inline void put_task_struct(struct task_struct *t)
1749{
1750 if (atomic_dec_and_test(&t->usage))
1751 __put_task_struct(t);
1752}
1753
1754extern void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1755extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1756
1757/*
1758 * Per process flags
1759 */
1760#define PF_STARTING 0x00000002 /* being created */
1761#define PF_EXITING 0x00000004 /* getting shut down */
1762#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */
1763#define PF_VCPU 0x00000010 /* I'm a virtual CPU */
1764#define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */
1765#define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
1766#define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */
1767#define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
1768#define PF_DUMPCORE 0x00000200 /* dumped core */
1769#define PF_SIGNALED 0x00000400 /* killed by a signal */
1770#define PF_MEMALLOC 0x00000800 /* Allocating memory */
1771#define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
1772#define PF_FREEZING 0x00004000 /* freeze in progress. do not account to load */
1773#define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
1774#define PF_FROZEN 0x00010000 /* frozen for system suspend */
1775#define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
1776#define PF_KSWAPD 0x00040000 /* I am kswapd */
1777#define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
1778#define PF_KTHREAD 0x00200000 /* I am a kernel thread */
1779#define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */
1780#define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1781#define PF_SPREAD_PAGE 0x01000000 /* Spread page cache over cpuset */
1782#define PF_SPREAD_SLAB 0x02000000 /* Spread some slab caches over cpuset */
1783#define PF_THREAD_BOUND 0x04000000 /* Thread bound to specific cpu */
1784#define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
1785#define PF_MEMPOLICY 0x10000000 /* Non-default NUMA mempolicy */
1786#define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
1787#define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */
1788#define PF_FREEZER_NOSIG 0x80000000 /* Freezer won't send signals to it */
1789
1790/*
1791 * Only the _current_ task can read/write to tsk->flags, but other
1792 * tasks can access tsk->flags in readonly mode for example
1793 * with tsk_used_math (like during threaded core dumping).
1794 * There is however an exception to this rule during ptrace
1795 * or during fork: the ptracer task is allowed to write to the
1796 * child->flags of its traced child (same goes for fork, the parent
1797 * can write to the child->flags), because we're guaranteed the
1798 * child is not running and in turn not changing child->flags
1799 * at the same time the parent does it.
1800 */
1801#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1802#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1803#define clear_used_math() clear_stopped_child_used_math(current)
1804#define set_used_math() set_stopped_child_used_math(current)
1805#define conditional_stopped_child_used_math(condition, child) \
1806 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1807#define conditional_used_math(condition) \
1808 conditional_stopped_child_used_math(condition, current)
1809#define copy_to_stopped_child_used_math(child) \
1810 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1811/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1812#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1813#define used_math() tsk_used_math(current)
1814
1815/*
1816 * task->group_stop flags
1817 */
1818#define GROUP_STOP_SIGMASK 0xffff /* signr of the last group stop */
1819#define GROUP_STOP_PENDING (1 << 16) /* task should stop for group stop */
1820#define GROUP_STOP_CONSUME (1 << 17) /* consume group stop count */
1821#define GROUP_STOP_TRAPPING (1 << 18) /* switching from STOPPED to TRACED */
1822#define GROUP_STOP_DEQUEUED (1 << 19) /* stop signal dequeued */
1823
1824extern void task_clear_group_stop_pending(struct task_struct *task);
1825
1826#ifdef CONFIG_PREEMPT_RCU
1827
1828#define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */
1829#define RCU_READ_UNLOCK_BOOSTED (1 << 1) /* boosted while in RCU read-side. */
1830#define RCU_READ_UNLOCK_NEED_QS (1 << 2) /* RCU core needs CPU response. */
1831
1832static inline void rcu_copy_process(struct task_struct *p)
1833{
1834 p->rcu_read_lock_nesting = 0;
1835 p->rcu_read_unlock_special = 0;
1836#ifdef CONFIG_TREE_PREEMPT_RCU
1837 p->rcu_blocked_node = NULL;
1838#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1839#ifdef CONFIG_RCU_BOOST
1840 p->rcu_boost_mutex = NULL;
1841#endif /* #ifdef CONFIG_RCU_BOOST */
1842 INIT_LIST_HEAD(&p->rcu_node_entry);
1843}
1844
1845#else
1846
1847static inline void rcu_copy_process(struct task_struct *p)
1848{
1849}
1850
1851#endif
1852
1853#ifdef CONFIG_SMP
1854extern void do_set_cpus_allowed(struct task_struct *p,
1855 const struct cpumask *new_mask);
1856
1857extern int set_cpus_allowed_ptr(struct task_struct *p,
1858 const struct cpumask *new_mask);
1859#else
1860static inline void do_set_cpus_allowed(struct task_struct *p,
1861 const struct cpumask *new_mask)
1862{
1863}
1864static inline int set_cpus_allowed_ptr(struct task_struct *p,
1865 const struct cpumask *new_mask)
1866{
1867 if (!cpumask_test_cpu(0, new_mask))
1868 return -EINVAL;
1869 return 0;
1870}
1871#endif
1872
1873#ifndef CONFIG_CPUMASK_OFFSTACK
1874static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1875{
1876 return set_cpus_allowed_ptr(p, &new_mask);
1877}
1878#endif
1879
1880/*
1881 * Do not use outside of architecture code which knows its limitations.
1882 *
1883 * sched_clock() has no promise of monotonicity or bounded drift between
1884 * CPUs, use (which you should not) requires disabling IRQs.
1885 *
1886 * Please use one of the three interfaces below.
1887 */
1888extern unsigned long long notrace sched_clock(void);
1889/*
1890 * See the comment in kernel/sched_clock.c
1891 */
1892extern u64 cpu_clock(int cpu);
1893extern u64 local_clock(void);
1894extern u64 sched_clock_cpu(int cpu);
1895
1896
1897extern void sched_clock_init(void);
1898
1899#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1900static inline void sched_clock_tick(void)
1901{
1902}
1903
1904static inline void sched_clock_idle_sleep_event(void)
1905{
1906}
1907
1908static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
1909{
1910}
1911#else
1912/*
1913 * Architectures can set this to 1 if they have specified
1914 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
1915 * but then during bootup it turns out that sched_clock()
1916 * is reliable after all:
1917 */
1918extern int sched_clock_stable;
1919
1920extern void sched_clock_tick(void);
1921extern void sched_clock_idle_sleep_event(void);
1922extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1923#endif
1924
1925#ifdef CONFIG_IRQ_TIME_ACCOUNTING
1926/*
1927 * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
1928 * The reason for this explicit opt-in is not to have perf penalty with
1929 * slow sched_clocks.
1930 */
1931extern void enable_sched_clock_irqtime(void);
1932extern void disable_sched_clock_irqtime(void);
1933#else
1934static inline void enable_sched_clock_irqtime(void) {}
1935static inline void disable_sched_clock_irqtime(void) {}
1936#endif
1937
1938extern unsigned long long
1939task_sched_runtime(struct task_struct *task);
1940extern unsigned long long thread_group_sched_runtime(struct task_struct *task);
1941
1942/* sched_exec is called by processes performing an exec */
1943#ifdef CONFIG_SMP
1944extern void sched_exec(void);
1945#else
1946#define sched_exec() {}
1947#endif
1948
1949extern void sched_clock_idle_sleep_event(void);
1950extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1951
1952#ifdef CONFIG_HOTPLUG_CPU
1953extern void idle_task_exit(void);
1954#else
1955static inline void idle_task_exit(void) {}
1956#endif
1957
1958#if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1959extern void wake_up_idle_cpu(int cpu);
1960#else
1961static inline void wake_up_idle_cpu(int cpu) { }
1962#endif
1963
1964extern unsigned int sysctl_sched_latency;
1965extern unsigned int sysctl_sched_min_granularity;
1966extern unsigned int sysctl_sched_wakeup_granularity;
1967extern unsigned int sysctl_sched_child_runs_first;
1968
1969enum sched_tunable_scaling {
1970 SCHED_TUNABLESCALING_NONE,
1971 SCHED_TUNABLESCALING_LOG,
1972 SCHED_TUNABLESCALING_LINEAR,
1973 SCHED_TUNABLESCALING_END,
1974};
1975extern enum sched_tunable_scaling sysctl_sched_tunable_scaling;
1976
1977#ifdef CONFIG_SCHED_DEBUG
1978extern unsigned int sysctl_sched_migration_cost;
1979extern unsigned int sysctl_sched_nr_migrate;
1980extern unsigned int sysctl_sched_time_avg;
1981extern unsigned int sysctl_timer_migration;
1982extern unsigned int sysctl_sched_shares_window;
1983
1984int sched_proc_update_handler(struct ctl_table *table, int write,
1985 void __user *buffer, size_t *length,
1986 loff_t *ppos);
1987#endif
1988#ifdef CONFIG_SCHED_DEBUG
1989static inline unsigned int get_sysctl_timer_migration(void)
1990{
1991 return sysctl_timer_migration;
1992}
1993#else
1994static inline unsigned int get_sysctl_timer_migration(void)
1995{
1996 return 1;
1997}
1998#endif
1999extern unsigned int sysctl_sched_rt_period;
2000extern int sysctl_sched_rt_runtime;
2001
2002int sched_rt_handler(struct ctl_table *table, int write,
2003 void __user *buffer, size_t *lenp,
2004 loff_t *ppos);
2005
2006#ifdef CONFIG_SCHED_AUTOGROUP
2007extern unsigned int sysctl_sched_autogroup_enabled;
2008
2009extern void sched_autogroup_create_attach(struct task_struct *p);
2010extern void sched_autogroup_detach(struct task_struct *p);
2011extern void sched_autogroup_fork(struct signal_struct *sig);
2012extern void sched_autogroup_exit(struct signal_struct *sig);
2013#ifdef CONFIG_PROC_FS
2014extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
2015extern int proc_sched_autogroup_set_nice(struct task_struct *p, int *nice);
2016#endif
2017#else
2018static inline void sched_autogroup_create_attach(struct task_struct *p) { }
2019static inline void sched_autogroup_detach(struct task_struct *p) { }
2020static inline void sched_autogroup_fork(struct signal_struct *sig) { }
2021static inline void sched_autogroup_exit(struct signal_struct *sig) { }
2022#endif
2023
2024#ifdef CONFIG_RT_MUTEXES
2025extern int rt_mutex_getprio(struct task_struct *p);
2026extern void rt_mutex_setprio(struct task_struct *p, int prio);
2027extern void rt_mutex_adjust_pi(struct task_struct *p);
2028#else
2029static inline int rt_mutex_getprio(struct task_struct *p)
2030{
2031 return p->normal_prio;
2032}
2033# define rt_mutex_adjust_pi(p) do { } while (0)
2034#endif
2035
2036extern bool yield_to(struct task_struct *p, bool preempt);
2037extern void set_user_nice(struct task_struct *p, long nice);
2038extern int task_prio(const struct task_struct *p);
2039extern int task_nice(const struct task_struct *p);
2040extern int can_nice(const struct task_struct *p, const int nice);
2041extern int task_curr(const struct task_struct *p);
2042extern int idle_cpu(int cpu);
2043extern int sched_setscheduler(struct task_struct *, int,
2044 const struct sched_param *);
2045extern int sched_setscheduler_nocheck(struct task_struct *, int,
2046 const struct sched_param *);
2047extern struct task_struct *idle_task(int cpu);
2048extern struct task_struct *curr_task(int cpu);
2049extern void set_curr_task(int cpu, struct task_struct *p);
2050
2051void yield(void);
2052
2053/*
2054 * The default (Linux) execution domain.
2055 */
2056extern struct exec_domain default_exec_domain;
2057
2058union thread_union {
2059 struct thread_info thread_info;
2060 unsigned long stack[THREAD_SIZE/sizeof(long)];
2061};
2062
2063#ifndef __HAVE_ARCH_KSTACK_END
2064static inline int kstack_end(void *addr)
2065{
2066 /* Reliable end of stack detection:
2067 * Some APM bios versions misalign the stack
2068 */
2069 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
2070}
2071#endif
2072
2073extern union thread_union init_thread_union;
2074extern struct task_struct init_task;
2075
2076extern struct mm_struct init_mm;
2077
2078extern struct pid_namespace init_pid_ns;
2079
2080/*
2081 * find a task by one of its numerical ids
2082 *
2083 * find_task_by_pid_ns():
2084 * finds a task by its pid in the specified namespace
2085 * find_task_by_vpid():
2086 * finds a task by its virtual pid
2087 *
2088 * see also find_vpid() etc in include/linux/pid.h
2089 */
2090
2091extern struct task_struct *find_task_by_vpid(pid_t nr);
2092extern struct task_struct *find_task_by_pid_ns(pid_t nr,
2093 struct pid_namespace *ns);
2094
2095extern void __set_special_pids(struct pid *pid);
2096
2097/* per-UID process charging. */
2098extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
2099static inline struct user_struct *get_uid(struct user_struct *u)
2100{
2101 atomic_inc(&u->__count);
2102 return u;
2103}
2104extern void free_uid(struct user_struct *);
2105extern void release_uids(struct user_namespace *ns);
2106
2107#include <asm/current.h>
2108
2109extern void xtime_update(unsigned long ticks);
2110
2111extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2112extern int wake_up_process(struct task_struct *tsk);
2113extern void wake_up_new_task(struct task_struct *tsk);
2114#ifdef CONFIG_SMP
2115 extern void kick_process(struct task_struct *tsk);
2116#else
2117 static inline void kick_process(struct task_struct *tsk) { }
2118#endif
2119extern void sched_fork(struct task_struct *p);
2120extern void sched_dead(struct task_struct *p);
2121
2122extern void proc_caches_init(void);
2123extern void flush_signals(struct task_struct *);
2124extern void __flush_signals(struct task_struct *);
2125extern void ignore_signals(struct task_struct *);
2126extern void flush_signal_handlers(struct task_struct *, int force_default);
2127extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2128
2129static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
2130{
2131 unsigned long flags;
2132 int ret;
2133
2134 spin_lock_irqsave(&tsk->sighand->siglock, flags);
2135 ret = dequeue_signal(tsk, mask, info);
2136 spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
2137
2138 return ret;
2139}
2140
2141extern void block_all_signals(int (*notifier)(void *priv), void *priv,
2142 sigset_t *mask);
2143extern void unblock_all_signals(void);
2144extern void release_task(struct task_struct * p);
2145extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2146extern int force_sigsegv(int, struct task_struct *);
2147extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2148extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2149extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2150extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
2151extern int kill_pgrp(struct pid *pid, int sig, int priv);
2152extern int kill_pid(struct pid *pid, int sig, int priv);
2153extern int kill_proc_info(int, struct siginfo *, pid_t);
2154extern int do_notify_parent(struct task_struct *, int);
2155extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2156extern void force_sig(int, struct task_struct *);
2157extern int send_sig(int, struct task_struct *, int);
2158extern int zap_other_threads(struct task_struct *p);
2159extern struct sigqueue *sigqueue_alloc(void);
2160extern void sigqueue_free(struct sigqueue *);
2161extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group);
2162extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2163extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
2164
2165static inline int kill_cad_pid(int sig, int priv)
2166{
2167 return kill_pid(cad_pid, sig, priv);
2168}
2169
2170/* These can be the second arg to send_sig_info/send_group_sig_info. */
2171#define SEND_SIG_NOINFO ((struct siginfo *) 0)
2172#define SEND_SIG_PRIV ((struct siginfo *) 1)
2173#define SEND_SIG_FORCED ((struct siginfo *) 2)
2174
2175/*
2176 * True if we are on the alternate signal stack.
2177 */
2178static inline int on_sig_stack(unsigned long sp)
2179{
2180#ifdef CONFIG_STACK_GROWSUP
2181 return sp >= current->sas_ss_sp &&
2182 sp - current->sas_ss_sp < current->sas_ss_size;
2183#else
2184 return sp > current->sas_ss_sp &&
2185 sp - current->sas_ss_sp <= current->sas_ss_size;
2186#endif
2187}
2188
2189static inline int sas_ss_flags(unsigned long sp)
2190{
2191 return (current->sas_ss_size == 0 ? SS_DISABLE
2192 : on_sig_stack(sp) ? SS_ONSTACK : 0);
2193}
2194
2195/*
2196 * Routines for handling mm_structs
2197 */
2198extern struct mm_struct * mm_alloc(void);
2199
2200/* mmdrop drops the mm and the page tables */
2201extern void __mmdrop(struct mm_struct *);
2202static inline void mmdrop(struct mm_struct * mm)
2203{
2204 if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2205 __mmdrop(mm);
2206}
2207
2208/* mmput gets rid of the mappings and all user-space */
2209extern void mmput(struct mm_struct *);
2210/* Grab a reference to a task's mm, if it is not already going away */
2211extern struct mm_struct *get_task_mm(struct task_struct *task);
2212/* Remove the current tasks stale references to the old mm_struct */
2213extern void mm_release(struct task_struct *, struct mm_struct *);
2214/* Allocate a new mm structure and copy contents from tsk->mm */
2215extern struct mm_struct *dup_mm(struct task_struct *tsk);
2216
2217extern int copy_thread(unsigned long, unsigned long, unsigned long,
2218 struct task_struct *, struct pt_regs *);
2219extern void flush_thread(void);
2220extern void exit_thread(void);
2221
2222extern void exit_files(struct task_struct *);
2223extern void __cleanup_sighand(struct sighand_struct *);
2224
2225extern void exit_itimers(struct signal_struct *);
2226extern void flush_itimer_signals(void);
2227
2228extern NORET_TYPE void do_group_exit(int);
2229
2230extern void daemonize(const char *, ...);
2231extern int allow_signal(int);
2232extern int disallow_signal(int);
2233
2234extern int do_execve(const char *,
2235 const char __user * const __user *,
2236 const char __user * const __user *, struct pt_regs *);
2237extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
2238struct task_struct *fork_idle(int);
2239
2240extern void set_task_comm(struct task_struct *tsk, char *from);
2241extern char *get_task_comm(char *to, struct task_struct *tsk);
2242
2243#ifdef CONFIG_SMP
2244void scheduler_ipi(void);
2245extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2246#else
2247static inline void scheduler_ipi(void) { }
2248static inline unsigned long wait_task_inactive(struct task_struct *p,
2249 long match_state)
2250{
2251 return 1;
2252}
2253#endif
2254
2255#define next_task(p) \
2256 list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2257
2258#define for_each_process(p) \
2259 for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2260
2261extern bool current_is_single_threaded(void);
2262
2263/*
2264 * Careful: do_each_thread/while_each_thread is a double loop so
2265 * 'break' will not work as expected - use goto instead.
2266 */
2267#define do_each_thread(g, t) \
2268 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2269
2270#define while_each_thread(g, t) \
2271 while ((t = next_thread(t)) != g)
2272
2273static inline int get_nr_threads(struct task_struct *tsk)
2274{
2275 return tsk->signal->nr_threads;
2276}
2277
2278/* de_thread depends on thread_group_leader not being a pid based check */
2279#define thread_group_leader(p) (p == p->group_leader)
2280
2281/* Do to the insanities of de_thread it is possible for a process
2282 * to have the pid of the thread group leader without actually being
2283 * the thread group leader. For iteration through the pids in proc
2284 * all we care about is that we have a task with the appropriate
2285 * pid, we don't actually care if we have the right task.
2286 */
2287static inline int has_group_leader_pid(struct task_struct *p)
2288{
2289 return p->pid == p->tgid;
2290}
2291
2292static inline
2293int same_thread_group(struct task_struct *p1, struct task_struct *p2)
2294{
2295 return p1->tgid == p2->tgid;
2296}
2297
2298static inline struct task_struct *next_thread(const struct task_struct *p)
2299{
2300 return list_entry_rcu(p->thread_group.next,
2301 struct task_struct, thread_group);
2302}
2303
2304static inline int thread_group_empty(struct task_struct *p)
2305{
2306 return list_empty(&p->thread_group);
2307}
2308
2309#define delay_group_leader(p) \
2310 (thread_group_leader(p) && !thread_group_empty(p))
2311
2312static inline int task_detached(struct task_struct *p)
2313{
2314 return p->exit_signal == -1;
2315}
2316
2317/*
2318 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2319 * subscriptions and synchronises with wait4(). Also used in procfs. Also
2320 * pins the final release of task.io_context. Also protects ->cpuset and
2321 * ->cgroup.subsys[].
2322 *
2323 * Nests both inside and outside of read_lock(&tasklist_lock).
2324 * It must not be nested with write_lock_irq(&tasklist_lock),
2325 * neither inside nor outside.
2326 */
2327static inline void task_lock(struct task_struct *p)
2328{
2329 spin_lock(&p->alloc_lock);
2330}
2331
2332static inline void task_unlock(struct task_struct *p)
2333{
2334 spin_unlock(&p->alloc_lock);
2335}
2336
2337extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2338 unsigned long *flags);
2339
2340#define lock_task_sighand(tsk, flags) \
2341({ struct sighand_struct *__ss; \
2342 __cond_lock(&(tsk)->sighand->siglock, \
2343 (__ss = __lock_task_sighand(tsk, flags))); \
2344 __ss; \
2345}) \
2346
2347static inline void unlock_task_sighand(struct task_struct *tsk,
2348 unsigned long *flags)
2349{
2350 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2351}
2352
2353/* See the declaration of threadgroup_fork_lock in signal_struct. */
2354#ifdef CONFIG_CGROUPS
2355static inline void threadgroup_fork_read_lock(struct task_struct *tsk)
2356{
2357 down_read(&tsk->signal->threadgroup_fork_lock);
2358}
2359static inline void threadgroup_fork_read_unlock(struct task_struct *tsk)
2360{
2361 up_read(&tsk->signal->threadgroup_fork_lock);
2362}
2363static inline void threadgroup_fork_write_lock(struct task_struct *tsk)
2364{
2365 down_write(&tsk->signal->threadgroup_fork_lock);
2366}
2367static inline void threadgroup_fork_write_unlock(struct task_struct *tsk)
2368{
2369 up_write(&tsk->signal->threadgroup_fork_lock);
2370}
2371#else
2372static inline void threadgroup_fork_read_lock(struct task_struct *tsk) {}
2373static inline void threadgroup_fork_read_unlock(struct task_struct *tsk) {}
2374static inline void threadgroup_fork_write_lock(struct task_struct *tsk) {}
2375static inline void threadgroup_fork_write_unlock(struct task_struct *tsk) {}
2376#endif
2377
2378#ifndef __HAVE_THREAD_FUNCTIONS
2379
2380#define task_thread_info(task) ((struct thread_info *)(task)->stack)
2381#define task_stack_page(task) ((task)->stack)
2382
2383static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2384{
2385 *task_thread_info(p) = *task_thread_info(org);
2386 task_thread_info(p)->task = p;
2387}
2388
2389static inline unsigned long *end_of_stack(struct task_struct *p)
2390{
2391 return (unsigned long *)(task_thread_info(p) + 1);
2392}
2393
2394#endif
2395
2396static inline int object_is_on_stack(void *obj)
2397{
2398 void *stack = task_stack_page(current);
2399
2400 return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2401}
2402
2403extern void thread_info_cache_init(void);
2404
2405#ifdef CONFIG_DEBUG_STACK_USAGE
2406static inline unsigned long stack_not_used(struct task_struct *p)
2407{
2408 unsigned long *n = end_of_stack(p);
2409
2410 do { /* Skip over canary */
2411 n++;
2412 } while (!*n);
2413
2414 return (unsigned long)n - (unsigned long)end_of_stack(p);
2415}
2416#endif
2417
2418/* set thread flags in other task's structures
2419 * - see asm/thread_info.h for TIF_xxxx flags available
2420 */
2421static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2422{
2423 set_ti_thread_flag(task_thread_info(tsk), flag);
2424}
2425
2426static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2427{
2428 clear_ti_thread_flag(task_thread_info(tsk), flag);
2429}
2430
2431static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2432{
2433 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2434}
2435
2436static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2437{
2438 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2439}
2440
2441static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2442{
2443 return test_ti_thread_flag(task_thread_info(tsk), flag);
2444}
2445
2446static inline void set_tsk_need_resched(struct task_struct *tsk)
2447{
2448 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2449}
2450
2451static inline void clear_tsk_need_resched(struct task_struct *tsk)
2452{
2453 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2454}
2455
2456static inline int test_tsk_need_resched(struct task_struct *tsk)
2457{
2458 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2459}
2460
2461static inline int restart_syscall(void)
2462{
2463 set_tsk_thread_flag(current, TIF_SIGPENDING);
2464 return -ERESTARTNOINTR;
2465}
2466
2467static inline int signal_pending(struct task_struct *p)
2468{
2469 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2470}
2471
2472static inline int __fatal_signal_pending(struct task_struct *p)
2473{
2474 return unlikely(sigismember(&p->pending.signal, SIGKILL));
2475}
2476
2477static inline int fatal_signal_pending(struct task_struct *p)
2478{
2479 return signal_pending(p) && __fatal_signal_pending(p);
2480}
2481
2482static inline int signal_pending_state(long state, struct task_struct *p)
2483{
2484 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2485 return 0;
2486 if (!signal_pending(p))
2487 return 0;
2488
2489 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2490}
2491
2492static inline int need_resched(void)
2493{
2494 return unlikely(test_thread_flag(TIF_NEED_RESCHED));
2495}
2496
2497/*
2498 * cond_resched() and cond_resched_lock(): latency reduction via
2499 * explicit rescheduling in places that are safe. The return
2500 * value indicates whether a reschedule was done in fact.
2501 * cond_resched_lock() will drop the spinlock before scheduling,
2502 * cond_resched_softirq() will enable bhs before scheduling.
2503 */
2504extern int _cond_resched(void);
2505
2506#define cond_resched() ({ \
2507 __might_sleep(__FILE__, __LINE__, 0); \
2508 _cond_resched(); \
2509})
2510
2511extern int __cond_resched_lock(spinlock_t *lock);
2512
2513#ifdef CONFIG_PREEMPT
2514#define PREEMPT_LOCK_OFFSET PREEMPT_OFFSET
2515#else
2516#define PREEMPT_LOCK_OFFSET 0
2517#endif
2518
2519#define cond_resched_lock(lock) ({ \
2520 __might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET); \
2521 __cond_resched_lock(lock); \
2522})
2523
2524extern int __cond_resched_softirq(void);
2525
2526#define cond_resched_softirq() ({ \
2527 __might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \
2528 __cond_resched_softirq(); \
2529})
2530
2531/*
2532 * Does a critical section need to be broken due to another
2533 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2534 * but a general need for low latency)
2535 */
2536static inline int spin_needbreak(spinlock_t *lock)
2537{
2538#ifdef CONFIG_PREEMPT
2539 return spin_is_contended(lock);
2540#else
2541 return 0;
2542#endif
2543}
2544
2545/*
2546 * Thread group CPU time accounting.
2547 */
2548void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2549void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2550
2551static inline void thread_group_cputime_init(struct signal_struct *sig)
2552{
2553 spin_lock_init(&sig->cputimer.lock);
2554}
2555
2556/*
2557 * Reevaluate whether the task has signals pending delivery.
2558 * Wake the task if so.
2559 * This is required every time the blocked sigset_t changes.
2560 * callers must hold sighand->siglock.
2561 */
2562extern void recalc_sigpending_and_wake(struct task_struct *t);
2563extern void recalc_sigpending(void);
2564
2565extern void signal_wake_up(struct task_struct *t, int resume_stopped);
2566
2567/*
2568 * Wrappers for p->thread_info->cpu access. No-op on UP.
2569 */
2570#ifdef CONFIG_SMP
2571
2572static inline unsigned int task_cpu(const struct task_struct *p)
2573{
2574 return task_thread_info(p)->cpu;
2575}
2576
2577extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2578
2579#else
2580
2581static inline unsigned int task_cpu(const struct task_struct *p)
2582{
2583 return 0;
2584}
2585
2586static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2587{
2588}
2589
2590#endif /* CONFIG_SMP */
2591
2592extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2593extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2594
2595extern void normalize_rt_tasks(void);
2596
2597#ifdef CONFIG_CGROUP_SCHED
2598
2599extern struct task_group root_task_group;
2600
2601extern struct task_group *sched_create_group(struct task_group *parent);
2602extern void sched_destroy_group(struct task_group *tg);
2603extern void sched_move_task(struct task_struct *tsk);
2604#ifdef CONFIG_FAIR_GROUP_SCHED
2605extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2606extern unsigned long sched_group_shares(struct task_group *tg);
2607#endif
2608#ifdef CONFIG_RT_GROUP_SCHED
2609extern int sched_group_set_rt_runtime(struct task_group *tg,
2610 long rt_runtime_us);
2611extern long sched_group_rt_runtime(struct task_group *tg);
2612extern int sched_group_set_rt_period(struct task_group *tg,
2613 long rt_period_us);
2614extern long sched_group_rt_period(struct task_group *tg);
2615extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
2616#endif
2617#endif
2618
2619extern int task_can_switch_user(struct user_struct *up,
2620 struct task_struct *tsk);
2621
2622#ifdef CONFIG_TASK_XACCT
2623static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2624{
2625 tsk->ioac.rchar += amt;
2626}
2627
2628static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2629{
2630 tsk->ioac.wchar += amt;
2631}
2632
2633static inline void inc_syscr(struct task_struct *tsk)
2634{
2635 tsk->ioac.syscr++;
2636}
2637
2638static inline void inc_syscw(struct task_struct *tsk)
2639{
2640 tsk->ioac.syscw++;
2641}
2642#else
2643static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2644{
2645}
2646
2647static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2648{
2649}
2650
2651static inline void inc_syscr(struct task_struct *tsk)
2652{
2653}
2654
2655static inline void inc_syscw(struct task_struct *tsk)
2656{
2657}
2658#endif
2659
2660#ifndef TASK_SIZE_OF
2661#define TASK_SIZE_OF(tsk) TASK_SIZE
2662#endif
2663
2664#ifdef CONFIG_MM_OWNER
2665extern void mm_update_next_owner(struct mm_struct *mm);
2666extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2667#else
2668static inline void mm_update_next_owner(struct mm_struct *mm)
2669{
2670}
2671
2672static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2673{
2674}
2675#endif /* CONFIG_MM_OWNER */
2676
2677static inline unsigned long task_rlimit(const struct task_struct *tsk,
2678 unsigned int limit)
2679{
2680 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur);
2681}
2682
2683static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
2684 unsigned int limit)
2685{
2686 return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max);
2687}
2688
2689static inline unsigned long rlimit(unsigned int limit)
2690{
2691 return task_rlimit(current, limit);
2692}
2693
2694static inline unsigned long rlimit_max(unsigned int limit)
2695{
2696 return task_rlimit_max(current, limit);
2697}
2698
2699#endif /* __KERNEL__ */
2700
2701#endif