sched.h revision 77e4ef99d1c596a31747668e5fd837f77b6349b6
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_FROZEN) == 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	 * group_rwsem prevents new tasks from entering the threadgroup and
639	 * member tasks from exiting,a more specifically, setting of
640	 * PF_EXITING.  fork and exit paths are protected with this rwsem
641	 * using threadgroup_change_begin/end().  Users which require
642	 * threadgroup to remain stable should use threadgroup_[un]lock()
643	 * which also takes care of exec path.  Currently, cgroup is the
644	 * only user.
645	 */
646	struct rw_semaphore group_rwsem;
647#endif
648
649	int oom_adj;		/* OOM kill score adjustment (bit shift) */
650	int oom_score_adj;	/* OOM kill score adjustment */
651	int oom_score_adj_min;	/* OOM kill score adjustment minimum value.
652				 * Only settable by CAP_SYS_RESOURCE. */
653
654	struct mutex cred_guard_mutex;	/* guard against foreign influences on
655					 * credential calculations
656					 * (notably. ptrace) */
657};
658
659/* Context switch must be unlocked if interrupts are to be enabled */
660#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
661# define __ARCH_WANT_UNLOCKED_CTXSW
662#endif
663
664/*
665 * Bits in flags field of signal_struct.
666 */
667#define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
668#define SIGNAL_STOP_CONTINUED	0x00000002 /* SIGCONT since WCONTINUED reap */
669#define SIGNAL_GROUP_EXIT	0x00000004 /* group exit in progress */
670/*
671 * Pending notifications to parent.
672 */
673#define SIGNAL_CLD_STOPPED	0x00000010
674#define SIGNAL_CLD_CONTINUED	0x00000020
675#define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
676
677#define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */
678
679/* If true, all threads except ->group_exit_task have pending SIGKILL */
680static inline int signal_group_exit(const struct signal_struct *sig)
681{
682	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
683		(sig->group_exit_task != NULL);
684}
685
686/*
687 * Some day this will be a full-fledged user tracking system..
688 */
689struct user_struct {
690	atomic_t __count;	/* reference count */
691	atomic_t processes;	/* How many processes does this user have? */
692	atomic_t files;		/* How many open files does this user have? */
693	atomic_t sigpending;	/* How many pending signals does this user have? */
694#ifdef CONFIG_INOTIFY_USER
695	atomic_t inotify_watches; /* How many inotify watches does this user have? */
696	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
697#endif
698#ifdef CONFIG_FANOTIFY
699	atomic_t fanotify_listeners;
700#endif
701#ifdef CONFIG_EPOLL
702	atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
703#endif
704#ifdef CONFIG_POSIX_MQUEUE
705	/* protected by mq_lock	*/
706	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
707#endif
708	unsigned long locked_shm; /* How many pages of mlocked shm ? */
709
710#ifdef CONFIG_KEYS
711	struct key *uid_keyring;	/* UID specific keyring */
712	struct key *session_keyring;	/* UID's default session keyring */
713#endif
714
715	/* Hash table maintenance information */
716	struct hlist_node uidhash_node;
717	uid_t uid;
718	struct user_namespace *user_ns;
719
720#ifdef CONFIG_PERF_EVENTS
721	atomic_long_t locked_vm;
722#endif
723};
724
725extern int uids_sysfs_init(void);
726
727extern struct user_struct *find_user(uid_t);
728
729extern struct user_struct root_user;
730#define INIT_USER (&root_user)
731
732
733struct backing_dev_info;
734struct reclaim_state;
735
736#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
737struct sched_info {
738	/* cumulative counters */
739	unsigned long pcount;	      /* # of times run on this cpu */
740	unsigned long long run_delay; /* time spent waiting on a runqueue */
741
742	/* timestamps */
743	unsigned long long last_arrival,/* when we last ran on a cpu */
744			   last_queued;	/* when we were last queued to run */
745};
746#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
747
748#ifdef CONFIG_TASK_DELAY_ACCT
749struct task_delay_info {
750	spinlock_t	lock;
751	unsigned int	flags;	/* Private per-task flags */
752
753	/* For each stat XXX, add following, aligned appropriately
754	 *
755	 * struct timespec XXX_start, XXX_end;
756	 * u64 XXX_delay;
757	 * u32 XXX_count;
758	 *
759	 * Atomicity of updates to XXX_delay, XXX_count protected by
760	 * single lock above (split into XXX_lock if contention is an issue).
761	 */
762
763	/*
764	 * XXX_count is incremented on every XXX operation, the delay
765	 * associated with the operation is added to XXX_delay.
766	 * XXX_delay contains the accumulated delay time in nanoseconds.
767	 */
768	struct timespec blkio_start, blkio_end;	/* Shared by blkio, swapin */
769	u64 blkio_delay;	/* wait for sync block io completion */
770	u64 swapin_delay;	/* wait for swapin block io completion */
771	u32 blkio_count;	/* total count of the number of sync block */
772				/* io operations performed */
773	u32 swapin_count;	/* total count of the number of swapin block */
774				/* io operations performed */
775
776	struct timespec freepages_start, freepages_end;
777	u64 freepages_delay;	/* wait for memory reclaim */
778	u32 freepages_count;	/* total count of memory reclaim */
779};
780#endif	/* CONFIG_TASK_DELAY_ACCT */
781
782static inline int sched_info_on(void)
783{
784#ifdef CONFIG_SCHEDSTATS
785	return 1;
786#elif defined(CONFIG_TASK_DELAY_ACCT)
787	extern int delayacct_on;
788	return delayacct_on;
789#else
790	return 0;
791#endif
792}
793
794enum cpu_idle_type {
795	CPU_IDLE,
796	CPU_NOT_IDLE,
797	CPU_NEWLY_IDLE,
798	CPU_MAX_IDLE_TYPES
799};
800
801/*
802 * Increase resolution of nice-level calculations for 64-bit architectures.
803 * The extra resolution improves shares distribution and load balancing of
804 * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
805 * hierarchies, especially on larger systems. This is not a user-visible change
806 * and does not change the user-interface for setting shares/weights.
807 *
808 * We increase resolution only if we have enough bits to allow this increased
809 * resolution (i.e. BITS_PER_LONG > 32). The costs for increasing resolution
810 * when BITS_PER_LONG <= 32 are pretty high and the returns do not justify the
811 * increased costs.
812 */
813#if 0 /* BITS_PER_LONG > 32 -- currently broken: it increases power usage under light load  */
814# define SCHED_LOAD_RESOLUTION	10
815# define scale_load(w)		((w) << SCHED_LOAD_RESOLUTION)
816# define scale_load_down(w)	((w) >> SCHED_LOAD_RESOLUTION)
817#else
818# define SCHED_LOAD_RESOLUTION	0
819# define scale_load(w)		(w)
820# define scale_load_down(w)	(w)
821#endif
822
823#define SCHED_LOAD_SHIFT	(10 + SCHED_LOAD_RESOLUTION)
824#define SCHED_LOAD_SCALE	(1L << SCHED_LOAD_SHIFT)
825
826/*
827 * Increase resolution of cpu_power calculations
828 */
829#define SCHED_POWER_SHIFT	10
830#define SCHED_POWER_SCALE	(1L << SCHED_POWER_SHIFT)
831
832/*
833 * sched-domains (multiprocessor balancing) declarations:
834 */
835#ifdef CONFIG_SMP
836#define SD_LOAD_BALANCE		0x0001	/* Do load balancing on this domain. */
837#define SD_BALANCE_NEWIDLE	0x0002	/* Balance when about to become idle */
838#define SD_BALANCE_EXEC		0x0004	/* Balance on exec */
839#define SD_BALANCE_FORK		0x0008	/* Balance on fork, clone */
840#define SD_BALANCE_WAKE		0x0010  /* Balance on wakeup */
841#define SD_WAKE_AFFINE		0x0020	/* Wake task to waking CPU */
842#define SD_PREFER_LOCAL		0x0040  /* Prefer to keep tasks local to this domain */
843#define SD_SHARE_CPUPOWER	0x0080	/* Domain members share cpu power */
844#define SD_POWERSAVINGS_BALANCE	0x0100	/* Balance for power savings */
845#define SD_SHARE_PKG_RESOURCES	0x0200	/* Domain members share cpu pkg resources */
846#define SD_SERIALIZE		0x0400	/* Only a single load balancing instance */
847#define SD_ASYM_PACKING		0x0800  /* Place busy groups earlier in the domain */
848#define SD_PREFER_SIBLING	0x1000	/* Prefer to place tasks in a sibling domain */
849#define SD_OVERLAP		0x2000	/* sched_domains of this level overlap */
850
851enum powersavings_balance_level {
852	POWERSAVINGS_BALANCE_NONE = 0,  /* No power saving load balance */
853	POWERSAVINGS_BALANCE_BASIC,	/* Fill one thread/core/package
854					 * first for long running threads
855					 */
856	POWERSAVINGS_BALANCE_WAKEUP,	/* Also bias task wakeups to semi-idle
857					 * cpu package for power savings
858					 */
859	MAX_POWERSAVINGS_BALANCE_LEVELS
860};
861
862extern int sched_mc_power_savings, sched_smt_power_savings;
863
864static inline int sd_balance_for_mc_power(void)
865{
866	if (sched_smt_power_savings)
867		return SD_POWERSAVINGS_BALANCE;
868
869	if (!sched_mc_power_savings)
870		return SD_PREFER_SIBLING;
871
872	return 0;
873}
874
875static inline int sd_balance_for_package_power(void)
876{
877	if (sched_mc_power_savings | sched_smt_power_savings)
878		return SD_POWERSAVINGS_BALANCE;
879
880	return SD_PREFER_SIBLING;
881}
882
883extern int __weak arch_sd_sibiling_asym_packing(void);
884
885/*
886 * Optimise SD flags for power savings:
887 * SD_BALANCE_NEWIDLE helps aggressive task consolidation and power savings.
888 * Keep default SD flags if sched_{smt,mc}_power_saving=0
889 */
890
891static inline int sd_power_saving_flags(void)
892{
893	if (sched_mc_power_savings | sched_smt_power_savings)
894		return SD_BALANCE_NEWIDLE;
895
896	return 0;
897}
898
899struct sched_group_power {
900	atomic_t ref;
901	/*
902	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
903	 * single CPU.
904	 */
905	unsigned int power, power_orig;
906};
907
908struct sched_group {
909	struct sched_group *next;	/* Must be a circular list */
910	atomic_t ref;
911
912	unsigned int group_weight;
913	struct sched_group_power *sgp;
914
915	/*
916	 * The CPUs this group covers.
917	 *
918	 * NOTE: this field is variable length. (Allocated dynamically
919	 * by attaching extra space to the end of the structure,
920	 * depending on how many CPUs the kernel has booted up with)
921	 */
922	unsigned long cpumask[0];
923};
924
925static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
926{
927	return to_cpumask(sg->cpumask);
928}
929
930struct sched_domain_attr {
931	int relax_domain_level;
932};
933
934#define SD_ATTR_INIT	(struct sched_domain_attr) {	\
935	.relax_domain_level = -1,			\
936}
937
938extern int sched_domain_level_max;
939
940struct sched_domain {
941	/* These fields must be setup */
942	struct sched_domain *parent;	/* top domain must be null terminated */
943	struct sched_domain *child;	/* bottom domain must be null terminated */
944	struct sched_group *groups;	/* the balancing groups of the domain */
945	unsigned long min_interval;	/* Minimum balance interval ms */
946	unsigned long max_interval;	/* Maximum balance interval ms */
947	unsigned int busy_factor;	/* less balancing by factor if busy */
948	unsigned int imbalance_pct;	/* No balance until over watermark */
949	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
950	unsigned int busy_idx;
951	unsigned int idle_idx;
952	unsigned int newidle_idx;
953	unsigned int wake_idx;
954	unsigned int forkexec_idx;
955	unsigned int smt_gain;
956	int flags;			/* See SD_* */
957	int level;
958
959	/* Runtime fields. */
960	unsigned long last_balance;	/* init to jiffies. units in jiffies */
961	unsigned int balance_interval;	/* initialise to 1. units in ms. */
962	unsigned int nr_balance_failed; /* initialise to 0 */
963
964	u64 last_update;
965
966#ifdef CONFIG_SCHEDSTATS
967	/* load_balance() stats */
968	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
969	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
970	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
971	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
972	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
973	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
974	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
975	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
976
977	/* Active load balancing */
978	unsigned int alb_count;
979	unsigned int alb_failed;
980	unsigned int alb_pushed;
981
982	/* SD_BALANCE_EXEC stats */
983	unsigned int sbe_count;
984	unsigned int sbe_balanced;
985	unsigned int sbe_pushed;
986
987	/* SD_BALANCE_FORK stats */
988	unsigned int sbf_count;
989	unsigned int sbf_balanced;
990	unsigned int sbf_pushed;
991
992	/* try_to_wake_up() stats */
993	unsigned int ttwu_wake_remote;
994	unsigned int ttwu_move_affine;
995	unsigned int ttwu_move_balance;
996#endif
997#ifdef CONFIG_SCHED_DEBUG
998	char *name;
999#endif
1000	union {
1001		void *private;		/* used during construction */
1002		struct rcu_head rcu;	/* used during destruction */
1003	};
1004
1005	unsigned int span_weight;
1006	/*
1007	 * Span of all CPUs in this domain.
1008	 *
1009	 * NOTE: this field is variable length. (Allocated dynamically
1010	 * by attaching extra space to the end of the structure,
1011	 * depending on how many CPUs the kernel has booted up with)
1012	 */
1013	unsigned long span[0];
1014};
1015
1016static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
1017{
1018	return to_cpumask(sd->span);
1019}
1020
1021extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1022				    struct sched_domain_attr *dattr_new);
1023
1024/* Allocate an array of sched domains, for partition_sched_domains(). */
1025cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
1026void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
1027
1028/* Test a flag in parent sched domain */
1029static inline int test_sd_parent(struct sched_domain *sd, int flag)
1030{
1031	if (sd->parent && (sd->parent->flags & flag))
1032		return 1;
1033
1034	return 0;
1035}
1036
1037unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu);
1038unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu);
1039
1040#else /* CONFIG_SMP */
1041
1042struct sched_domain_attr;
1043
1044static inline void
1045partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1046			struct sched_domain_attr *dattr_new)
1047{
1048}
1049#endif	/* !CONFIG_SMP */
1050
1051
1052struct io_context;			/* See blkdev.h */
1053
1054
1055#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1056extern void prefetch_stack(struct task_struct *t);
1057#else
1058static inline void prefetch_stack(struct task_struct *t) { }
1059#endif
1060
1061struct audit_context;		/* See audit.c */
1062struct mempolicy;
1063struct pipe_inode_info;
1064struct uts_namespace;
1065
1066struct rq;
1067struct sched_domain;
1068
1069/*
1070 * wake flags
1071 */
1072#define WF_SYNC		0x01		/* waker goes to sleep after wakup */
1073#define WF_FORK		0x02		/* child wakeup after fork */
1074#define WF_MIGRATED	0x04		/* internal use, task got migrated */
1075
1076#define ENQUEUE_WAKEUP		1
1077#define ENQUEUE_HEAD		2
1078#ifdef CONFIG_SMP
1079#define ENQUEUE_WAKING		4	/* sched_class::task_waking was called */
1080#else
1081#define ENQUEUE_WAKING		0
1082#endif
1083
1084#define DEQUEUE_SLEEP		1
1085
1086struct sched_class {
1087	const struct sched_class *next;
1088
1089	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1090	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1091	void (*yield_task) (struct rq *rq);
1092	bool (*yield_to_task) (struct rq *rq, struct task_struct *p, bool preempt);
1093
1094	void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
1095
1096	struct task_struct * (*pick_next_task) (struct rq *rq);
1097	void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1098
1099#ifdef CONFIG_SMP
1100	int  (*select_task_rq)(struct task_struct *p, int sd_flag, int flags);
1101
1102	void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
1103	void (*post_schedule) (struct rq *this_rq);
1104	void (*task_waking) (struct task_struct *task);
1105	void (*task_woken) (struct rq *this_rq, struct task_struct *task);
1106
1107	void (*set_cpus_allowed)(struct task_struct *p,
1108				 const struct cpumask *newmask);
1109
1110	void (*rq_online)(struct rq *rq);
1111	void (*rq_offline)(struct rq *rq);
1112#endif
1113
1114	void (*set_curr_task) (struct rq *rq);
1115	void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1116	void (*task_fork) (struct task_struct *p);
1117
1118	void (*switched_from) (struct rq *this_rq, struct task_struct *task);
1119	void (*switched_to) (struct rq *this_rq, struct task_struct *task);
1120	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1121			     int oldprio);
1122
1123	unsigned int (*get_rr_interval) (struct rq *rq,
1124					 struct task_struct *task);
1125
1126#ifdef CONFIG_FAIR_GROUP_SCHED
1127	void (*task_move_group) (struct task_struct *p, int on_rq);
1128#endif
1129};
1130
1131struct load_weight {
1132	unsigned long weight, inv_weight;
1133};
1134
1135#ifdef CONFIG_SCHEDSTATS
1136struct sched_statistics {
1137	u64			wait_start;
1138	u64			wait_max;
1139	u64			wait_count;
1140	u64			wait_sum;
1141	u64			iowait_count;
1142	u64			iowait_sum;
1143
1144	u64			sleep_start;
1145	u64			sleep_max;
1146	s64			sum_sleep_runtime;
1147
1148	u64			block_start;
1149	u64			block_max;
1150	u64			exec_max;
1151	u64			slice_max;
1152
1153	u64			nr_migrations_cold;
1154	u64			nr_failed_migrations_affine;
1155	u64			nr_failed_migrations_running;
1156	u64			nr_failed_migrations_hot;
1157	u64			nr_forced_migrations;
1158
1159	u64			nr_wakeups;
1160	u64			nr_wakeups_sync;
1161	u64			nr_wakeups_migrate;
1162	u64			nr_wakeups_local;
1163	u64			nr_wakeups_remote;
1164	u64			nr_wakeups_affine;
1165	u64			nr_wakeups_affine_attempts;
1166	u64			nr_wakeups_passive;
1167	u64			nr_wakeups_idle;
1168};
1169#endif
1170
1171struct sched_entity {
1172	struct load_weight	load;		/* for load-balancing */
1173	struct rb_node		run_node;
1174	struct list_head	group_node;
1175	unsigned int		on_rq;
1176
1177	u64			exec_start;
1178	u64			sum_exec_runtime;
1179	u64			vruntime;
1180	u64			prev_sum_exec_runtime;
1181
1182	u64			nr_migrations;
1183
1184#ifdef CONFIG_SCHEDSTATS
1185	struct sched_statistics statistics;
1186#endif
1187
1188#ifdef CONFIG_FAIR_GROUP_SCHED
1189	struct sched_entity	*parent;
1190	/* rq on which this entity is (to be) queued: */
1191	struct cfs_rq		*cfs_rq;
1192	/* rq "owned" by this entity/group: */
1193	struct cfs_rq		*my_q;
1194#endif
1195};
1196
1197struct sched_rt_entity {
1198	struct list_head run_list;
1199	unsigned long timeout;
1200	unsigned int time_slice;
1201	int nr_cpus_allowed;
1202
1203	struct sched_rt_entity *back;
1204#ifdef CONFIG_RT_GROUP_SCHED
1205	struct sched_rt_entity	*parent;
1206	/* rq on which this entity is (to be) queued: */
1207	struct rt_rq		*rt_rq;
1208	/* rq "owned" by this entity/group: */
1209	struct rt_rq		*my_q;
1210#endif
1211};
1212
1213struct rcu_node;
1214
1215enum perf_event_task_context {
1216	perf_invalid_context = -1,
1217	perf_hw_context = 0,
1218	perf_sw_context,
1219	perf_nr_task_contexts,
1220};
1221
1222struct task_struct {
1223	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
1224	void *stack;
1225	atomic_t usage;
1226	unsigned int flags;	/* per process flags, defined below */
1227	unsigned int ptrace;
1228
1229#ifdef CONFIG_SMP
1230	struct llist_node wake_entry;
1231	int on_cpu;
1232#endif
1233	int on_rq;
1234
1235	int prio, static_prio, normal_prio;
1236	unsigned int rt_priority;
1237	const struct sched_class *sched_class;
1238	struct sched_entity se;
1239	struct sched_rt_entity rt;
1240
1241#ifdef CONFIG_PREEMPT_NOTIFIERS
1242	/* list of struct preempt_notifier: */
1243	struct hlist_head preempt_notifiers;
1244#endif
1245
1246	/*
1247	 * fpu_counter contains the number of consecutive context switches
1248	 * that the FPU is used. If this is over a threshold, the lazy fpu
1249	 * saving becomes unlazy to save the trap. This is an unsigned char
1250	 * so that after 256 times the counter wraps and the behavior turns
1251	 * lazy again; this to deal with bursty apps that only use FPU for
1252	 * a short time
1253	 */
1254	unsigned char fpu_counter;
1255#ifdef CONFIG_BLK_DEV_IO_TRACE
1256	unsigned int btrace_seq;
1257#endif
1258
1259	unsigned int policy;
1260	cpumask_t cpus_allowed;
1261
1262#ifdef CONFIG_PREEMPT_RCU
1263	int rcu_read_lock_nesting;
1264	char rcu_read_unlock_special;
1265	struct list_head rcu_node_entry;
1266#endif /* #ifdef CONFIG_PREEMPT_RCU */
1267#ifdef CONFIG_TREE_PREEMPT_RCU
1268	struct rcu_node *rcu_blocked_node;
1269#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1270#ifdef CONFIG_RCU_BOOST
1271	struct rt_mutex *rcu_boost_mutex;
1272#endif /* #ifdef CONFIG_RCU_BOOST */
1273
1274#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1275	struct sched_info sched_info;
1276#endif
1277
1278	struct list_head tasks;
1279#ifdef CONFIG_SMP
1280	struct plist_node pushable_tasks;
1281#endif
1282
1283	struct mm_struct *mm, *active_mm;
1284#ifdef CONFIG_COMPAT_BRK
1285	unsigned brk_randomized:1;
1286#endif
1287#if defined(SPLIT_RSS_COUNTING)
1288	struct task_rss_stat	rss_stat;
1289#endif
1290/* task state */
1291	int exit_state;
1292	int exit_code, exit_signal;
1293	int pdeath_signal;  /*  The signal sent when the parent dies  */
1294	unsigned int jobctl;	/* JOBCTL_*, siglock protected */
1295	/* ??? */
1296	unsigned int personality;
1297	unsigned did_exec:1;
1298	unsigned in_execve:1;	/* Tell the LSMs that the process is doing an
1299				 * execve */
1300	unsigned in_iowait:1;
1301
1302
1303	/* Revert to default priority/policy when forking */
1304	unsigned sched_reset_on_fork:1;
1305	unsigned sched_contributes_to_load:1;
1306
1307	pid_t pid;
1308	pid_t tgid;
1309
1310#ifdef CONFIG_CC_STACKPROTECTOR
1311	/* Canary value for the -fstack-protector gcc feature */
1312	unsigned long stack_canary;
1313#endif
1314
1315	/*
1316	 * pointers to (original) parent process, youngest child, younger sibling,
1317	 * older sibling, respectively.  (p->father can be replaced with
1318	 * p->real_parent->pid)
1319	 */
1320	struct task_struct *real_parent; /* real parent process */
1321	struct task_struct *parent; /* recipient of SIGCHLD, wait4() reports */
1322	/*
1323	 * children/sibling forms the list of my natural children
1324	 */
1325	struct list_head children;	/* list of my children */
1326	struct list_head sibling;	/* linkage in my parent's children list */
1327	struct task_struct *group_leader;	/* threadgroup leader */
1328
1329	/*
1330	 * ptraced is the list of tasks this task is using ptrace on.
1331	 * This includes both natural children and PTRACE_ATTACH targets.
1332	 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1333	 */
1334	struct list_head ptraced;
1335	struct list_head ptrace_entry;
1336
1337	/* PID/PID hash table linkage. */
1338	struct pid_link pids[PIDTYPE_MAX];
1339	struct list_head thread_group;
1340
1341	struct completion *vfork_done;		/* for vfork() */
1342	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
1343	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
1344
1345	cputime_t utime, stime, utimescaled, stimescaled;
1346	cputime_t gtime;
1347#ifndef CONFIG_VIRT_CPU_ACCOUNTING
1348	cputime_t prev_utime, prev_stime;
1349#endif
1350	unsigned long nvcsw, nivcsw; /* context switch counts */
1351	struct timespec start_time; 		/* monotonic time */
1352	struct timespec real_start_time;	/* boot based time */
1353/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1354	unsigned long min_flt, maj_flt;
1355
1356	struct task_cputime cputime_expires;
1357	struct list_head cpu_timers[3];
1358
1359/* process credentials */
1360	const struct cred __rcu *real_cred; /* objective and real subjective task
1361					 * credentials (COW) */
1362	const struct cred __rcu *cred;	/* effective (overridable) subjective task
1363					 * credentials (COW) */
1364	struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */
1365
1366	char comm[TASK_COMM_LEN]; /* executable name excluding path
1367				     - access with [gs]et_task_comm (which lock
1368				       it with task_lock())
1369				     - initialized normally by setup_new_exec */
1370/* file system info */
1371	int link_count, total_link_count;
1372#ifdef CONFIG_SYSVIPC
1373/* ipc stuff */
1374	struct sysv_sem sysvsem;
1375#endif
1376#ifdef CONFIG_DETECT_HUNG_TASK
1377/* hung task detection */
1378	unsigned long last_switch_count;
1379#endif
1380/* CPU-specific state of this task */
1381	struct thread_struct thread;
1382/* filesystem information */
1383	struct fs_struct *fs;
1384/* open file information */
1385	struct files_struct *files;
1386/* namespaces */
1387	struct nsproxy *nsproxy;
1388/* signal handlers */
1389	struct signal_struct *signal;
1390	struct sighand_struct *sighand;
1391
1392	sigset_t blocked, real_blocked;
1393	sigset_t saved_sigmask;	/* restored if set_restore_sigmask() was used */
1394	struct sigpending pending;
1395
1396	unsigned long sas_ss_sp;
1397	size_t sas_ss_size;
1398	int (*notifier)(void *priv);
1399	void *notifier_data;
1400	sigset_t *notifier_mask;
1401	struct audit_context *audit_context;
1402#ifdef CONFIG_AUDITSYSCALL
1403	uid_t loginuid;
1404	unsigned int sessionid;
1405#endif
1406	seccomp_t seccomp;
1407
1408/* Thread group tracking */
1409   	u32 parent_exec_id;
1410   	u32 self_exec_id;
1411/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1412 * mempolicy */
1413	spinlock_t alloc_lock;
1414
1415#ifdef CONFIG_GENERIC_HARDIRQS
1416	/* IRQ handler threads */
1417	struct irqaction *irqaction;
1418#endif
1419
1420	/* Protection of the PI data structures: */
1421	raw_spinlock_t pi_lock;
1422
1423#ifdef CONFIG_RT_MUTEXES
1424	/* PI waiters blocked on a rt_mutex held by this task */
1425	struct plist_head pi_waiters;
1426	/* Deadlock detection and priority inheritance handling */
1427	struct rt_mutex_waiter *pi_blocked_on;
1428#endif
1429
1430#ifdef CONFIG_DEBUG_MUTEXES
1431	/* mutex deadlock detection */
1432	struct mutex_waiter *blocked_on;
1433#endif
1434#ifdef CONFIG_TRACE_IRQFLAGS
1435	unsigned int irq_events;
1436	unsigned long hardirq_enable_ip;
1437	unsigned long hardirq_disable_ip;
1438	unsigned int hardirq_enable_event;
1439	unsigned int hardirq_disable_event;
1440	int hardirqs_enabled;
1441	int hardirq_context;
1442	unsigned long softirq_disable_ip;
1443	unsigned long softirq_enable_ip;
1444	unsigned int softirq_disable_event;
1445	unsigned int softirq_enable_event;
1446	int softirqs_enabled;
1447	int softirq_context;
1448#endif
1449#ifdef CONFIG_LOCKDEP
1450# define MAX_LOCK_DEPTH 48UL
1451	u64 curr_chain_key;
1452	int lockdep_depth;
1453	unsigned int lockdep_recursion;
1454	struct held_lock held_locks[MAX_LOCK_DEPTH];
1455	gfp_t lockdep_reclaim_gfp;
1456#endif
1457
1458/* journalling filesystem info */
1459	void *journal_info;
1460
1461/* stacked block device info */
1462	struct bio_list *bio_list;
1463
1464#ifdef CONFIG_BLOCK
1465/* stack plugging */
1466	struct blk_plug *plug;
1467#endif
1468
1469/* VM state */
1470	struct reclaim_state *reclaim_state;
1471
1472	struct backing_dev_info *backing_dev_info;
1473
1474	struct io_context *io_context;
1475
1476	unsigned long ptrace_message;
1477	siginfo_t *last_siginfo; /* For ptrace use.  */
1478	struct task_io_accounting ioac;
1479#if defined(CONFIG_TASK_XACCT)
1480	u64 acct_rss_mem1;	/* accumulated rss usage */
1481	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1482	cputime_t acct_timexpd;	/* stime + utime since last update */
1483#endif
1484#ifdef CONFIG_CPUSETS
1485	nodemask_t mems_allowed;	/* Protected by alloc_lock */
1486	int mems_allowed_change_disable;
1487	int cpuset_mem_spread_rotor;
1488	int cpuset_slab_spread_rotor;
1489#endif
1490#ifdef CONFIG_CGROUPS
1491	/* Control Group info protected by css_set_lock */
1492	struct css_set __rcu *cgroups;
1493	/* cg_list protected by css_set_lock and tsk->alloc_lock */
1494	struct list_head cg_list;
1495#endif
1496#ifdef CONFIG_FUTEX
1497	struct robust_list_head __user *robust_list;
1498#ifdef CONFIG_COMPAT
1499	struct compat_robust_list_head __user *compat_robust_list;
1500#endif
1501	struct list_head pi_state_list;
1502	struct futex_pi_state *pi_state_cache;
1503#endif
1504#ifdef CONFIG_PERF_EVENTS
1505	struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1506	struct mutex perf_event_mutex;
1507	struct list_head perf_event_list;
1508#endif
1509#ifdef CONFIG_NUMA
1510	struct mempolicy *mempolicy;	/* Protected by alloc_lock */
1511	short il_next;
1512	short pref_node_fork;
1513#endif
1514	struct rcu_head rcu;
1515
1516	/*
1517	 * cache last used pipe for splice
1518	 */
1519	struct pipe_inode_info *splice_pipe;
1520#ifdef	CONFIG_TASK_DELAY_ACCT
1521	struct task_delay_info *delays;
1522#endif
1523#ifdef CONFIG_FAULT_INJECTION
1524	int make_it_fail;
1525#endif
1526	/*
1527	 * when (nr_dirtied >= nr_dirtied_pause), it's time to call
1528	 * balance_dirty_pages() for some dirty throttling pause
1529	 */
1530	int nr_dirtied;
1531	int nr_dirtied_pause;
1532
1533#ifdef CONFIG_LATENCYTOP
1534	int latency_record_count;
1535	struct latency_record latency_record[LT_SAVECOUNT];
1536#endif
1537	/*
1538	 * time slack values; these are used to round up poll() and
1539	 * select() etc timeout values. These are in nanoseconds.
1540	 */
1541	unsigned long timer_slack_ns;
1542	unsigned long default_timer_slack_ns;
1543
1544	struct list_head	*scm_work_list;
1545#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1546	/* Index of current stored address in ret_stack */
1547	int curr_ret_stack;
1548	/* Stack of return addresses for return function tracing */
1549	struct ftrace_ret_stack	*ret_stack;
1550	/* time stamp for last schedule */
1551	unsigned long long ftrace_timestamp;
1552	/*
1553	 * Number of functions that haven't been traced
1554	 * because of depth overrun.
1555	 */
1556	atomic_t trace_overrun;
1557	/* Pause for the tracing */
1558	atomic_t tracing_graph_pause;
1559#endif
1560#ifdef CONFIG_TRACING
1561	/* state flags for use by tracers */
1562	unsigned long trace;
1563	/* bitmask and counter of trace recursion */
1564	unsigned long trace_recursion;
1565#endif /* CONFIG_TRACING */
1566#ifdef CONFIG_CGROUP_MEM_RES_CTLR /* memcg uses this to do batch job */
1567	struct memcg_batch_info {
1568		int do_batch;	/* incremented when batch uncharge started */
1569		struct mem_cgroup *memcg; /* target memcg of uncharge */
1570		unsigned long nr_pages;	/* uncharged usage */
1571		unsigned long memsw_nr_pages; /* uncharged mem+swap usage */
1572	} memcg_batch;
1573#endif
1574#ifdef CONFIG_HAVE_HW_BREAKPOINT
1575	atomic_t ptrace_bp_refcnt;
1576#endif
1577};
1578
1579/* Future-safe accessor for struct task_struct's cpus_allowed. */
1580#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1581
1582/*
1583 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1584 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1585 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1586 * values are inverted: lower p->prio value means higher priority.
1587 *
1588 * The MAX_USER_RT_PRIO value allows the actual maximum
1589 * RT priority to be separate from the value exported to
1590 * user-space.  This allows kernel threads to set their
1591 * priority to a value higher than any user task. Note:
1592 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1593 */
1594
1595#define MAX_USER_RT_PRIO	100
1596#define MAX_RT_PRIO		MAX_USER_RT_PRIO
1597
1598#define MAX_PRIO		(MAX_RT_PRIO + 40)
1599#define DEFAULT_PRIO		(MAX_RT_PRIO + 20)
1600
1601static inline int rt_prio(int prio)
1602{
1603	if (unlikely(prio < MAX_RT_PRIO))
1604		return 1;
1605	return 0;
1606}
1607
1608static inline int rt_task(struct task_struct *p)
1609{
1610	return rt_prio(p->prio);
1611}
1612
1613static inline struct pid *task_pid(struct task_struct *task)
1614{
1615	return task->pids[PIDTYPE_PID].pid;
1616}
1617
1618static inline struct pid *task_tgid(struct task_struct *task)
1619{
1620	return task->group_leader->pids[PIDTYPE_PID].pid;
1621}
1622
1623/*
1624 * Without tasklist or rcu lock it is not safe to dereference
1625 * the result of task_pgrp/task_session even if task == current,
1626 * we can race with another thread doing sys_setsid/sys_setpgid.
1627 */
1628static inline struct pid *task_pgrp(struct task_struct *task)
1629{
1630	return task->group_leader->pids[PIDTYPE_PGID].pid;
1631}
1632
1633static inline struct pid *task_session(struct task_struct *task)
1634{
1635	return task->group_leader->pids[PIDTYPE_SID].pid;
1636}
1637
1638struct pid_namespace;
1639
1640/*
1641 * the helpers to get the task's different pids as they are seen
1642 * from various namespaces
1643 *
1644 * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1645 * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1646 *                     current.
1647 * task_xid_nr_ns()  : id seen from the ns specified;
1648 *
1649 * set_task_vxid()   : assigns a virtual id to a task;
1650 *
1651 * see also pid_nr() etc in include/linux/pid.h
1652 */
1653pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1654			struct pid_namespace *ns);
1655
1656static inline pid_t task_pid_nr(struct task_struct *tsk)
1657{
1658	return tsk->pid;
1659}
1660
1661static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1662					struct pid_namespace *ns)
1663{
1664	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1665}
1666
1667static inline pid_t task_pid_vnr(struct task_struct *tsk)
1668{
1669	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1670}
1671
1672
1673static inline pid_t task_tgid_nr(struct task_struct *tsk)
1674{
1675	return tsk->tgid;
1676}
1677
1678pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1679
1680static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1681{
1682	return pid_vnr(task_tgid(tsk));
1683}
1684
1685
1686static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1687					struct pid_namespace *ns)
1688{
1689	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1690}
1691
1692static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1693{
1694	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1695}
1696
1697
1698static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1699					struct pid_namespace *ns)
1700{
1701	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1702}
1703
1704static inline pid_t task_session_vnr(struct task_struct *tsk)
1705{
1706	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1707}
1708
1709/* obsolete, do not use */
1710static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1711{
1712	return task_pgrp_nr_ns(tsk, &init_pid_ns);
1713}
1714
1715/**
1716 * pid_alive - check that a task structure is not stale
1717 * @p: Task structure to be checked.
1718 *
1719 * Test if a process is not yet dead (at most zombie state)
1720 * If pid_alive fails, then pointers within the task structure
1721 * can be stale and must not be dereferenced.
1722 */
1723static inline int pid_alive(struct task_struct *p)
1724{
1725	return p->pids[PIDTYPE_PID].pid != NULL;
1726}
1727
1728/**
1729 * is_global_init - check if a task structure is init
1730 * @tsk: Task structure to be checked.
1731 *
1732 * Check if a task structure is the first user space task the kernel created.
1733 */
1734static inline int is_global_init(struct task_struct *tsk)
1735{
1736	return tsk->pid == 1;
1737}
1738
1739/*
1740 * is_container_init:
1741 * check whether in the task is init in its own pid namespace.
1742 */
1743extern int is_container_init(struct task_struct *tsk);
1744
1745extern struct pid *cad_pid;
1746
1747extern void free_task(struct task_struct *tsk);
1748#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1749
1750extern void __put_task_struct(struct task_struct *t);
1751
1752static inline void put_task_struct(struct task_struct *t)
1753{
1754	if (atomic_dec_and_test(&t->usage))
1755		__put_task_struct(t);
1756}
1757
1758extern void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1759extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1760
1761/*
1762 * Per process flags
1763 */
1764#define PF_STARTING	0x00000002	/* being created */
1765#define PF_EXITING	0x00000004	/* getting shut down */
1766#define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
1767#define PF_VCPU		0x00000010	/* I'm a virtual CPU */
1768#define PF_WQ_WORKER	0x00000020	/* I'm a workqueue worker */
1769#define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
1770#define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
1771#define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
1772#define PF_DUMPCORE	0x00000200	/* dumped core */
1773#define PF_SIGNALED	0x00000400	/* killed by a signal */
1774#define PF_MEMALLOC	0x00000800	/* Allocating memory */
1775#define PF_NPROC_EXCEEDED 0x00001000	/* set_user noticed that RLIMIT_NPROC was exceeded */
1776#define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
1777#define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
1778#define PF_FROZEN	0x00010000	/* frozen for system suspend */
1779#define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
1780#define PF_KSWAPD	0x00040000	/* I am kswapd */
1781#define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
1782#define PF_KTHREAD	0x00200000	/* I am a kernel thread */
1783#define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
1784#define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
1785#define PF_SPREAD_PAGE	0x01000000	/* Spread page cache over cpuset */
1786#define PF_SPREAD_SLAB	0x02000000	/* Spread some slab caches over cpuset */
1787#define PF_THREAD_BOUND	0x04000000	/* Thread bound to specific cpu */
1788#define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
1789#define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
1790#define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
1791#define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezable */
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#ifdef CONFIG_CGROUPS
2377static inline void threadgroup_change_begin(struct task_struct *tsk)
2378{
2379	down_read(&tsk->signal->group_rwsem);
2380}
2381static inline void threadgroup_change_end(struct task_struct *tsk)
2382{
2383	up_read(&tsk->signal->group_rwsem);
2384}
2385
2386/**
2387 * threadgroup_lock - lock threadgroup
2388 * @tsk: member task of the threadgroup to lock
2389 *
2390 * Lock the threadgroup @tsk belongs to.  No new task is allowed to enter
2391 * and member tasks aren't allowed to exit (as indicated by PF_EXITING) or
2392 * perform exec.  This is useful for cases where the threadgroup needs to
2393 * stay stable across blockable operations.
2394 *
2395 * fork and exit paths explicitly call threadgroup_change_{begin|end}() for
2396 * synchronization.  While held, no new task will be added to threadgroup
2397 * and no existing live task will have its PF_EXITING set.
2398 *
2399 * During exec, a task goes and puts its thread group through unusual
2400 * changes.  After de-threading, exclusive access is assumed to resources
2401 * which are usually shared by tasks in the same group - e.g. sighand may
2402 * be replaced with a new one.  Also, the exec'ing task takes over group
2403 * leader role including its pid.  Exclude these changes while locked by
2404 * grabbing cred_guard_mutex which is used to synchronize exec path.
2405 */
2406static inline void threadgroup_lock(struct task_struct *tsk)
2407{
2408	/*
2409	 * exec uses exit for de-threading nesting group_rwsem inside
2410	 * cred_guard_mutex. Grab cred_guard_mutex first.
2411	 */
2412	mutex_lock(&tsk->signal->cred_guard_mutex);
2413	down_write(&tsk->signal->group_rwsem);
2414}
2415
2416/**
2417 * threadgroup_unlock - unlock threadgroup
2418 * @tsk: member task of the threadgroup to unlock
2419 *
2420 * Reverse threadgroup_lock().
2421 */
2422static inline void threadgroup_unlock(struct task_struct *tsk)
2423{
2424	up_write(&tsk->signal->group_rwsem);
2425	mutex_unlock(&tsk->signal->cred_guard_mutex);
2426}
2427#else
2428static inline void threadgroup_change_begin(struct task_struct *tsk) {}
2429static inline void threadgroup_change_end(struct task_struct *tsk) {}
2430static inline void threadgroup_lock(struct task_struct *tsk) {}
2431static inline void threadgroup_unlock(struct task_struct *tsk) {}
2432#endif
2433
2434#ifndef __HAVE_THREAD_FUNCTIONS
2435
2436#define task_thread_info(task)	((struct thread_info *)(task)->stack)
2437#define task_stack_page(task)	((task)->stack)
2438
2439static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2440{
2441	*task_thread_info(p) = *task_thread_info(org);
2442	task_thread_info(p)->task = p;
2443}
2444
2445static inline unsigned long *end_of_stack(struct task_struct *p)
2446{
2447	return (unsigned long *)(task_thread_info(p) + 1);
2448}
2449
2450#endif
2451
2452static inline int object_is_on_stack(void *obj)
2453{
2454	void *stack = task_stack_page(current);
2455
2456	return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2457}
2458
2459extern void thread_info_cache_init(void);
2460
2461#ifdef CONFIG_DEBUG_STACK_USAGE
2462static inline unsigned long stack_not_used(struct task_struct *p)
2463{
2464	unsigned long *n = end_of_stack(p);
2465
2466	do { 	/* Skip over canary */
2467		n++;
2468	} while (!*n);
2469
2470	return (unsigned long)n - (unsigned long)end_of_stack(p);
2471}
2472#endif
2473
2474/* set thread flags in other task's structures
2475 * - see asm/thread_info.h for TIF_xxxx flags available
2476 */
2477static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2478{
2479	set_ti_thread_flag(task_thread_info(tsk), flag);
2480}
2481
2482static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2483{
2484	clear_ti_thread_flag(task_thread_info(tsk), flag);
2485}
2486
2487static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2488{
2489	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2490}
2491
2492static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2493{
2494	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2495}
2496
2497static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2498{
2499	return test_ti_thread_flag(task_thread_info(tsk), flag);
2500}
2501
2502static inline void set_tsk_need_resched(struct task_struct *tsk)
2503{
2504	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2505}
2506
2507static inline void clear_tsk_need_resched(struct task_struct *tsk)
2508{
2509	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2510}
2511
2512static inline int test_tsk_need_resched(struct task_struct *tsk)
2513{
2514	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2515}
2516
2517static inline int restart_syscall(void)
2518{
2519	set_tsk_thread_flag(current, TIF_SIGPENDING);
2520	return -ERESTARTNOINTR;
2521}
2522
2523static inline int signal_pending(struct task_struct *p)
2524{
2525	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2526}
2527
2528static inline int __fatal_signal_pending(struct task_struct *p)
2529{
2530	return unlikely(sigismember(&p->pending.signal, SIGKILL));
2531}
2532
2533static inline int fatal_signal_pending(struct task_struct *p)
2534{
2535	return signal_pending(p) && __fatal_signal_pending(p);
2536}
2537
2538static inline int signal_pending_state(long state, struct task_struct *p)
2539{
2540	if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2541		return 0;
2542	if (!signal_pending(p))
2543		return 0;
2544
2545	return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2546}
2547
2548static inline int need_resched(void)
2549{
2550	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
2551}
2552
2553/*
2554 * cond_resched() and cond_resched_lock(): latency reduction via
2555 * explicit rescheduling in places that are safe. The return
2556 * value indicates whether a reschedule was done in fact.
2557 * cond_resched_lock() will drop the spinlock before scheduling,
2558 * cond_resched_softirq() will enable bhs before scheduling.
2559 */
2560extern int _cond_resched(void);
2561
2562#define cond_resched() ({			\
2563	__might_sleep(__FILE__, __LINE__, 0);	\
2564	_cond_resched();			\
2565})
2566
2567extern int __cond_resched_lock(spinlock_t *lock);
2568
2569#ifdef CONFIG_PREEMPT_COUNT
2570#define PREEMPT_LOCK_OFFSET	PREEMPT_OFFSET
2571#else
2572#define PREEMPT_LOCK_OFFSET	0
2573#endif
2574
2575#define cond_resched_lock(lock) ({				\
2576	__might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);	\
2577	__cond_resched_lock(lock);				\
2578})
2579
2580extern int __cond_resched_softirq(void);
2581
2582#define cond_resched_softirq() ({					\
2583	__might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET);	\
2584	__cond_resched_softirq();					\
2585})
2586
2587/*
2588 * Does a critical section need to be broken due to another
2589 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2590 * but a general need for low latency)
2591 */
2592static inline int spin_needbreak(spinlock_t *lock)
2593{
2594#ifdef CONFIG_PREEMPT
2595	return spin_is_contended(lock);
2596#else
2597	return 0;
2598#endif
2599}
2600
2601/*
2602 * Thread group CPU time accounting.
2603 */
2604void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2605void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2606
2607static inline void thread_group_cputime_init(struct signal_struct *sig)
2608{
2609	raw_spin_lock_init(&sig->cputimer.lock);
2610}
2611
2612/*
2613 * Reevaluate whether the task has signals pending delivery.
2614 * Wake the task if so.
2615 * This is required every time the blocked sigset_t changes.
2616 * callers must hold sighand->siglock.
2617 */
2618extern void recalc_sigpending_and_wake(struct task_struct *t);
2619extern void recalc_sigpending(void);
2620
2621extern void signal_wake_up(struct task_struct *t, int resume_stopped);
2622
2623/*
2624 * Wrappers for p->thread_info->cpu access. No-op on UP.
2625 */
2626#ifdef CONFIG_SMP
2627
2628static inline unsigned int task_cpu(const struct task_struct *p)
2629{
2630	return task_thread_info(p)->cpu;
2631}
2632
2633extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2634
2635#else
2636
2637static inline unsigned int task_cpu(const struct task_struct *p)
2638{
2639	return 0;
2640}
2641
2642static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2643{
2644}
2645
2646#endif /* CONFIG_SMP */
2647
2648extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2649extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2650
2651extern void normalize_rt_tasks(void);
2652
2653#ifdef CONFIG_CGROUP_SCHED
2654
2655extern struct task_group root_task_group;
2656
2657extern struct task_group *sched_create_group(struct task_group *parent);
2658extern void sched_destroy_group(struct task_group *tg);
2659extern void sched_move_task(struct task_struct *tsk);
2660#ifdef CONFIG_FAIR_GROUP_SCHED
2661extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2662extern unsigned long sched_group_shares(struct task_group *tg);
2663#endif
2664#ifdef CONFIG_RT_GROUP_SCHED
2665extern int sched_group_set_rt_runtime(struct task_group *tg,
2666				      long rt_runtime_us);
2667extern long sched_group_rt_runtime(struct task_group *tg);
2668extern int sched_group_set_rt_period(struct task_group *tg,
2669				      long rt_period_us);
2670extern long sched_group_rt_period(struct task_group *tg);
2671extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
2672#endif
2673#endif
2674
2675extern int task_can_switch_user(struct user_struct *up,
2676					struct task_struct *tsk);
2677
2678#ifdef CONFIG_TASK_XACCT
2679static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2680{
2681	tsk->ioac.rchar += amt;
2682}
2683
2684static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2685{
2686	tsk->ioac.wchar += amt;
2687}
2688
2689static inline void inc_syscr(struct task_struct *tsk)
2690{
2691	tsk->ioac.syscr++;
2692}
2693
2694static inline void inc_syscw(struct task_struct *tsk)
2695{
2696	tsk->ioac.syscw++;
2697}
2698#else
2699static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2700{
2701}
2702
2703static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2704{
2705}
2706
2707static inline void inc_syscr(struct task_struct *tsk)
2708{
2709}
2710
2711static inline void inc_syscw(struct task_struct *tsk)
2712{
2713}
2714#endif
2715
2716#ifndef TASK_SIZE_OF
2717#define TASK_SIZE_OF(tsk)	TASK_SIZE
2718#endif
2719
2720#ifdef CONFIG_MM_OWNER
2721extern void mm_update_next_owner(struct mm_struct *mm);
2722extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2723#else
2724static inline void mm_update_next_owner(struct mm_struct *mm)
2725{
2726}
2727
2728static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2729{
2730}
2731#endif /* CONFIG_MM_OWNER */
2732
2733static inline unsigned long task_rlimit(const struct task_struct *tsk,
2734		unsigned int limit)
2735{
2736	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur);
2737}
2738
2739static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
2740		unsigned int limit)
2741{
2742	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max);
2743}
2744
2745static inline unsigned long rlimit(unsigned int limit)
2746{
2747	return task_rlimit(current, limit);
2748}
2749
2750static inline unsigned long rlimit_max(unsigned int limit)
2751{
2752	return task_rlimit_max(current, limit);
2753}
2754
2755#endif /* __KERNEL__ */
2756
2757#endif
2758