sched.h revision 669c55e9f99b90e46eaa0f98a67ec53d46dc969a
1#ifndef _LINUX_SCHED_H
2#define _LINUX_SCHED_H
3
4/*
5 * cloning flags:
6 */
7#define CSIGNAL		0x000000ff	/* signal mask to be sent at exit */
8#define CLONE_VM	0x00000100	/* set if VM shared between processes */
9#define CLONE_FS	0x00000200	/* set if fs info shared between processes */
10#define CLONE_FILES	0x00000400	/* set if open files shared between processes */
11#define CLONE_SIGHAND	0x00000800	/* set if signal handlers and blocked signals shared */
12#define CLONE_PTRACE	0x00002000	/* set if we want to let tracing continue on the child too */
13#define CLONE_VFORK	0x00004000	/* set if the parent wants the child to wake it up on mm_release */
14#define CLONE_PARENT	0x00008000	/* set if we want to have the same parent as the cloner */
15#define CLONE_THREAD	0x00010000	/* Same thread group? */
16#define CLONE_NEWNS	0x00020000	/* New namespace group? */
17#define CLONE_SYSVSEM	0x00040000	/* share system V SEM_UNDO semantics */
18#define CLONE_SETTLS	0x00080000	/* create a new TLS for the child */
19#define CLONE_PARENT_SETTID	0x00100000	/* set the TID in the parent */
20#define CLONE_CHILD_CLEARTID	0x00200000	/* clear the TID in the child */
21#define CLONE_DETACHED		0x00400000	/* Unused, ignored */
22#define CLONE_UNTRACED		0x00800000	/* set if the tracing process can't force CLONE_PTRACE on this clone */
23#define CLONE_CHILD_SETTID	0x01000000	/* set the TID in the child */
24#define CLONE_STOPPED		0x02000000	/* Start in stopped state */
25#define CLONE_NEWUTS		0x04000000	/* New utsname group? */
26#define CLONE_NEWIPC		0x08000000	/* New ipcs */
27#define CLONE_NEWUSER		0x10000000	/* New user namespace */
28#define CLONE_NEWPID		0x20000000	/* New pid namespace */
29#define CLONE_NEWNET		0x40000000	/* New network namespace */
30#define CLONE_IO		0x80000000	/* Clone io context */
31
32/*
33 * Scheduling policies
34 */
35#define SCHED_NORMAL		0
36#define SCHED_FIFO		1
37#define SCHED_RR		2
38#define SCHED_BATCH		3
39/* SCHED_ISO: reserved but not implemented yet */
40#define SCHED_IDLE		5
41/* Can be ORed in to make sure the process is reverted back to SCHED_NORMAL on fork */
42#define SCHED_RESET_ON_FORK     0x40000000
43
44#ifdef __KERNEL__
45
46struct sched_param {
47	int sched_priority;
48};
49
50#include <asm/param.h>	/* for HZ */
51
52#include <linux/capability.h>
53#include <linux/threads.h>
54#include <linux/kernel.h>
55#include <linux/types.h>
56#include <linux/timex.h>
57#include <linux/jiffies.h>
58#include <linux/rbtree.h>
59#include <linux/thread_info.h>
60#include <linux/cpumask.h>
61#include <linux/errno.h>
62#include <linux/nodemask.h>
63#include <linux/mm_types.h>
64
65#include <asm/system.h>
66#include <asm/page.h>
67#include <asm/ptrace.h>
68#include <asm/cputime.h>
69
70#include <linux/smp.h>
71#include <linux/sem.h>
72#include <linux/signal.h>
73#include <linux/path.h>
74#include <linux/compiler.h>
75#include <linux/completion.h>
76#include <linux/pid.h>
77#include <linux/percpu.h>
78#include <linux/topology.h>
79#include <linux/proportions.h>
80#include <linux/seccomp.h>
81#include <linux/rcupdate.h>
82#include <linux/rculist.h>
83#include <linux/rtmutex.h>
84
85#include <linux/time.h>
86#include <linux/param.h>
87#include <linux/resource.h>
88#include <linux/timer.h>
89#include <linux/hrtimer.h>
90#include <linux/task_io_accounting.h>
91#include <linux/kobject.h>
92#include <linux/latencytop.h>
93#include <linux/cred.h>
94
95#include <asm/processor.h>
96
97struct exec_domain;
98struct futex_pi_state;
99struct robust_list_head;
100struct bio_list;
101struct fs_struct;
102struct bts_context;
103struct perf_event_context;
104
105/*
106 * List of flags we want to share for kernel threads,
107 * if only because they are not used by them anyway.
108 */
109#define CLONE_KERNEL	(CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
110
111/*
112 * These are the constant used to fake the fixed-point load-average
113 * counting. Some notes:
114 *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
115 *    a load-average precision of 10 bits integer + 11 bits fractional
116 *  - if you want to count load-averages more often, you need more
117 *    precision, or rounding will get you. With 2-second counting freq,
118 *    the EXP_n values would be 1981, 2034 and 2043 if still using only
119 *    11 bit fractions.
120 */
121extern unsigned long avenrun[];		/* Load averages */
122extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
123
124#define FSHIFT		11		/* nr of bits of precision */
125#define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
126#define LOAD_FREQ	(5*HZ+1)	/* 5 sec intervals */
127#define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
128#define EXP_5		2014		/* 1/exp(5sec/5min) */
129#define EXP_15		2037		/* 1/exp(5sec/15min) */
130
131#define CALC_LOAD(load,exp,n) \
132	load *= exp; \
133	load += n*(FIXED_1-exp); \
134	load >>= FSHIFT;
135
136extern unsigned long total_forks;
137extern int nr_threads;
138DECLARE_PER_CPU(unsigned long, process_counts);
139extern int nr_processes(void);
140extern unsigned long nr_running(void);
141extern unsigned long nr_uninterruptible(void);
142extern unsigned long nr_iowait(void);
143extern unsigned long nr_iowait_cpu(void);
144extern unsigned long this_cpu_load(void);
145
146
147extern void calc_global_load(void);
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_stopped_or_traced(task)	\
219			((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
220#define task_contributes_to_load(task)	\
221				((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
222				 (task->flags & PF_FREEZING) == 0)
223
224#define __set_task_state(tsk, state_value)		\
225	do { (tsk)->state = (state_value); } while (0)
226#define set_task_state(tsk, state_value)		\
227	set_mb((tsk)->state, (state_value))
228
229/*
230 * set_current_state() includes a barrier so that the write of current->state
231 * is correctly serialised wrt the caller's subsequent test of whether to
232 * actually sleep:
233 *
234 *	set_current_state(TASK_UNINTERRUPTIBLE);
235 *	if (do_i_need_to_sleep())
236 *		schedule();
237 *
238 * If the caller does not need such serialisation then use __set_current_state()
239 */
240#define __set_current_state(state_value)			\
241	do { current->state = (state_value); } while (0)
242#define set_current_state(state_value)		\
243	set_mb(current->state, (state_value))
244
245/* Task command name length */
246#define TASK_COMM_LEN 16
247
248#include <linux/spinlock.h>
249
250/*
251 * This serializes "schedule()" and also protects
252 * the run-queue from deletions/modifications (but
253 * _adding_ to the beginning of the run-queue has
254 * a separate lock).
255 */
256extern rwlock_t tasklist_lock;
257extern spinlock_t mmlist_lock;
258
259struct task_struct;
260
261#ifdef CONFIG_PROVE_RCU
262extern int lockdep_tasklist_lock_is_held(void);
263#endif /* #ifdef CONFIG_PROVE_RCU */
264
265extern void sched_init(void);
266extern void sched_init_smp(void);
267extern asmlinkage void schedule_tail(struct task_struct *prev);
268extern void init_idle(struct task_struct *idle, int cpu);
269extern void init_idle_bootup_task(struct task_struct *idle);
270
271extern int runqueue_is_locked(int cpu);
272extern void task_rq_unlock_wait(struct task_struct *p);
273
274extern cpumask_var_t nohz_cpu_mask;
275#if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
276extern int select_nohz_load_balancer(int cpu);
277extern int get_nohz_load_balancer(void);
278extern int nohz_ratelimit(int cpu);
279#else
280static inline int select_nohz_load_balancer(int cpu)
281{
282	return 0;
283}
284
285static inline int nohz_ratelimit(int cpu)
286{
287	return 0;
288}
289#endif
290
291/*
292 * Only dump TASK_* tasks. (0 for all tasks)
293 */
294extern void show_state_filter(unsigned long state_filter);
295
296static inline void show_state(void)
297{
298	show_state_filter(0);
299}
300
301extern void show_regs(struct pt_regs *);
302
303/*
304 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
305 * task), SP is the stack pointer of the first frame that should be shown in the back
306 * trace (or NULL if the entire call-chain of the task should be shown).
307 */
308extern void show_stack(struct task_struct *task, unsigned long *sp);
309
310void io_schedule(void);
311long io_schedule_timeout(long timeout);
312
313extern void cpu_init (void);
314extern void trap_init(void);
315extern void update_process_times(int user);
316extern void scheduler_tick(void);
317
318extern void sched_show_task(struct task_struct *p);
319
320#ifdef CONFIG_DETECT_SOFTLOCKUP
321extern void softlockup_tick(void);
322extern void touch_softlockup_watchdog(void);
323extern void touch_softlockup_watchdog_sync(void);
324extern void touch_all_softlockup_watchdogs(void);
325extern int proc_dosoftlockup_thresh(struct ctl_table *table, int write,
326				    void __user *buffer,
327				    size_t *lenp, loff_t *ppos);
328extern unsigned int  softlockup_panic;
329extern int softlockup_thresh;
330#else
331static inline void softlockup_tick(void)
332{
333}
334static inline void touch_softlockup_watchdog(void)
335{
336}
337static inline void touch_softlockup_watchdog_sync(void)
338{
339}
340static inline void touch_all_softlockup_watchdogs(void)
341{
342}
343#endif
344
345#ifdef CONFIG_DETECT_HUNG_TASK
346extern unsigned int  sysctl_hung_task_panic;
347extern unsigned long sysctl_hung_task_check_count;
348extern unsigned long sysctl_hung_task_timeout_secs;
349extern unsigned long sysctl_hung_task_warnings;
350extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
351					 void __user *buffer,
352					 size_t *lenp, loff_t *ppos);
353#endif
354
355/* Attach to any functions which should be ignored in wchan output. */
356#define __sched		__attribute__((__section__(".sched.text")))
357
358/* Linker adds these: start and end of __sched functions */
359extern char __sched_text_start[], __sched_text_end[];
360
361/* Is this address in the __sched functions? */
362extern int in_sched_functions(unsigned long addr);
363
364#define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
365extern signed long schedule_timeout(signed long timeout);
366extern signed long schedule_timeout_interruptible(signed long timeout);
367extern signed long schedule_timeout_killable(signed long timeout);
368extern signed long schedule_timeout_uninterruptible(signed long timeout);
369asmlinkage void schedule(void);
370extern int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner);
371
372struct nsproxy;
373struct user_namespace;
374
375/*
376 * Default maximum number of active map areas, this limits the number of vmas
377 * per mm struct. Users can overwrite this number by sysctl but there is a
378 * problem.
379 *
380 * When a program's coredump is generated as ELF format, a section is created
381 * per a vma. In ELF, the number of sections is represented in unsigned short.
382 * This means the number of sections should be smaller than 65535 at coredump.
383 * Because the kernel adds some informative sections to a image of program at
384 * generating coredump, we need some margin. The number of extra sections is
385 * 1-3 now and depends on arch. We use "5" as safe margin, here.
386 */
387#define MAPCOUNT_ELF_CORE_MARGIN	(5)
388#define DEFAULT_MAX_MAP_COUNT	(USHORT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
389
390extern int sysctl_max_map_count;
391
392#include <linux/aio.h>
393
394#ifdef CONFIG_MMU
395extern void arch_pick_mmap_layout(struct mm_struct *mm);
396extern unsigned long
397arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
398		       unsigned long, unsigned long);
399extern unsigned long
400arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
401			  unsigned long len, unsigned long pgoff,
402			  unsigned long flags);
403extern void arch_unmap_area(struct mm_struct *, unsigned long);
404extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
405#else
406static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
407#endif
408
409
410extern void set_dumpable(struct mm_struct *mm, int value);
411extern int get_dumpable(struct mm_struct *mm);
412
413/* mm flags */
414/* dumpable bits */
415#define MMF_DUMPABLE      0  /* core dump is permitted */
416#define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
417
418#define MMF_DUMPABLE_BITS 2
419#define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
420
421/* coredump filter bits */
422#define MMF_DUMP_ANON_PRIVATE	2
423#define MMF_DUMP_ANON_SHARED	3
424#define MMF_DUMP_MAPPED_PRIVATE	4
425#define MMF_DUMP_MAPPED_SHARED	5
426#define MMF_DUMP_ELF_HEADERS	6
427#define MMF_DUMP_HUGETLB_PRIVATE 7
428#define MMF_DUMP_HUGETLB_SHARED  8
429
430#define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
431#define MMF_DUMP_FILTER_BITS	7
432#define MMF_DUMP_FILTER_MASK \
433	(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
434#define MMF_DUMP_FILTER_DEFAULT \
435	((1 << MMF_DUMP_ANON_PRIVATE) |	(1 << MMF_DUMP_ANON_SHARED) |\
436	 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
437
438#ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
439# define MMF_DUMP_MASK_DEFAULT_ELF	(1 << MMF_DUMP_ELF_HEADERS)
440#else
441# define MMF_DUMP_MASK_DEFAULT_ELF	0
442#endif
443					/* leave room for more dump flags */
444#define MMF_VM_MERGEABLE	16	/* KSM may merge identical pages */
445
446#define MMF_INIT_MASK		(MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
447
448struct sighand_struct {
449	atomic_t		count;
450	struct k_sigaction	action[_NSIG];
451	spinlock_t		siglock;
452	wait_queue_head_t	signalfd_wqh;
453};
454
455struct pacct_struct {
456	int			ac_flag;
457	long			ac_exitcode;
458	unsigned long		ac_mem;
459	cputime_t		ac_utime, ac_stime;
460	unsigned long		ac_minflt, ac_majflt;
461};
462
463struct cpu_itimer {
464	cputime_t expires;
465	cputime_t incr;
466	u32 error;
467	u32 incr_error;
468};
469
470/**
471 * struct task_cputime - collected CPU time counts
472 * @utime:		time spent in user mode, in &cputime_t units
473 * @stime:		time spent in kernel mode, in &cputime_t units
474 * @sum_exec_runtime:	total time spent on the CPU, in nanoseconds
475 *
476 * This structure groups together three kinds of CPU time that are
477 * tracked for threads and thread groups.  Most things considering
478 * CPU time want to group these counts together and treat all three
479 * of them in parallel.
480 */
481struct task_cputime {
482	cputime_t utime;
483	cputime_t stime;
484	unsigned long long sum_exec_runtime;
485};
486/* Alternate field names when used to cache expirations. */
487#define prof_exp	stime
488#define virt_exp	utime
489#define sched_exp	sum_exec_runtime
490
491#define INIT_CPUTIME	\
492	(struct task_cputime) {					\
493		.utime = cputime_zero,				\
494		.stime = cputime_zero,				\
495		.sum_exec_runtime = 0,				\
496	}
497
498/*
499 * Disable preemption until the scheduler is running.
500 * Reset by start_kernel()->sched_init()->init_idle().
501 *
502 * We include PREEMPT_ACTIVE to avoid cond_resched() from working
503 * before the scheduler is active -- see should_resched().
504 */
505#define INIT_PREEMPT_COUNT	(1 + PREEMPT_ACTIVE)
506
507/**
508 * struct thread_group_cputimer - thread group interval timer counts
509 * @cputime:		thread group interval timers.
510 * @running:		non-zero when there are timers running and
511 * 			@cputime receives updates.
512 * @lock:		lock for fields in this struct.
513 *
514 * This structure contains the version of task_cputime, above, that is
515 * used for thread group CPU timer calculations.
516 */
517struct thread_group_cputimer {
518	struct task_cputime cputime;
519	int running;
520	spinlock_t lock;
521};
522
523/*
524 * NOTE! "signal_struct" does not have it's own
525 * locking, because a shared signal_struct always
526 * implies a shared sighand_struct, so locking
527 * sighand_struct is always a proper superset of
528 * the locking of signal_struct.
529 */
530struct signal_struct {
531	atomic_t		count;
532	atomic_t		live;
533
534	wait_queue_head_t	wait_chldexit;	/* for wait4() */
535
536	/* current thread group signal load-balancing target: */
537	struct task_struct	*curr_target;
538
539	/* shared signal handling: */
540	struct sigpending	shared_pending;
541
542	/* thread group exit support */
543	int			group_exit_code;
544	/* overloaded:
545	 * - notify group_exit_task when ->count is equal to notify_count
546	 * - everyone except group_exit_task is stopped during signal delivery
547	 *   of fatal signals, group_exit_task processes the signal.
548	 */
549	int			notify_count;
550	struct task_struct	*group_exit_task;
551
552	/* thread group stop support, overloads group_exit_code too */
553	int			group_stop_count;
554	unsigned int		flags; /* see SIGNAL_* flags below */
555
556	/* POSIX.1b Interval Timers */
557	struct list_head posix_timers;
558
559	/* ITIMER_REAL timer for the process */
560	struct hrtimer real_timer;
561	struct pid *leader_pid;
562	ktime_t it_real_incr;
563
564	/*
565	 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
566	 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
567	 * values are defined to 0 and 1 respectively
568	 */
569	struct cpu_itimer it[2];
570
571	/*
572	 * Thread group totals for process CPU timers.
573	 * See thread_group_cputimer(), et al, for details.
574	 */
575	struct thread_group_cputimer cputimer;
576
577	/* Earliest-expiration cache. */
578	struct task_cputime cputime_expires;
579
580	struct list_head cpu_timers[3];
581
582	struct pid *tty_old_pgrp;
583
584	/* boolean value for session group leader */
585	int leader;
586
587	struct tty_struct *tty; /* NULL if no tty */
588
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
637	int oom_adj;	/* OOM kill score adjustment (bit shift) */
638};
639
640/* Context switch must be unlocked if interrupts are to be enabled */
641#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
642# define __ARCH_WANT_UNLOCKED_CTXSW
643#endif
644
645/*
646 * Bits in flags field of signal_struct.
647 */
648#define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
649#define SIGNAL_STOP_DEQUEUED	0x00000002 /* stop signal dequeued */
650#define SIGNAL_STOP_CONTINUED	0x00000004 /* SIGCONT since WCONTINUED reap */
651#define SIGNAL_GROUP_EXIT	0x00000008 /* group exit in progress */
652/*
653 * Pending notifications to parent.
654 */
655#define SIGNAL_CLD_STOPPED	0x00000010
656#define SIGNAL_CLD_CONTINUED	0x00000020
657#define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
658
659#define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */
660
661/* If true, all threads except ->group_exit_task have pending SIGKILL */
662static inline int signal_group_exit(const struct signal_struct *sig)
663{
664	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
665		(sig->group_exit_task != NULL);
666}
667
668/*
669 * Some day this will be a full-fledged user tracking system..
670 */
671struct user_struct {
672	atomic_t __count;	/* reference count */
673	atomic_t processes;	/* How many processes does this user have? */
674	atomic_t files;		/* How many open files does this user have? */
675	atomic_t sigpending;	/* How many pending signals does this user have? */
676#ifdef CONFIG_INOTIFY_USER
677	atomic_t inotify_watches; /* How many inotify watches does this user have? */
678	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
679#endif
680#ifdef CONFIG_EPOLL
681	atomic_t epoll_watches;	/* The number of file descriptors currently watched */
682#endif
683#ifdef CONFIG_POSIX_MQUEUE
684	/* protected by mq_lock	*/
685	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
686#endif
687	unsigned long locked_shm; /* How many pages of mlocked shm ? */
688
689#ifdef CONFIG_KEYS
690	struct key *uid_keyring;	/* UID specific keyring */
691	struct key *session_keyring;	/* UID's default session keyring */
692#endif
693
694	/* Hash table maintenance information */
695	struct hlist_node uidhash_node;
696	uid_t uid;
697	struct user_namespace *user_ns;
698
699#ifdef CONFIG_PERF_EVENTS
700	atomic_long_t locked_vm;
701#endif
702};
703
704extern int uids_sysfs_init(void);
705
706extern struct user_struct *find_user(uid_t);
707
708extern struct user_struct root_user;
709#define INIT_USER (&root_user)
710
711
712struct backing_dev_info;
713struct reclaim_state;
714
715#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
716struct sched_info {
717	/* cumulative counters */
718	unsigned long pcount;	      /* # of times run on this cpu */
719	unsigned long long run_delay; /* time spent waiting on a runqueue */
720
721	/* timestamps */
722	unsigned long long last_arrival,/* when we last ran on a cpu */
723			   last_queued;	/* when we were last queued to run */
724#ifdef CONFIG_SCHEDSTATS
725	/* BKL stats */
726	unsigned int bkl_count;
727#endif
728};
729#endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
730
731#ifdef CONFIG_TASK_DELAY_ACCT
732struct task_delay_info {
733	spinlock_t	lock;
734	unsigned int	flags;	/* Private per-task flags */
735
736	/* For each stat XXX, add following, aligned appropriately
737	 *
738	 * struct timespec XXX_start, XXX_end;
739	 * u64 XXX_delay;
740	 * u32 XXX_count;
741	 *
742	 * Atomicity of updates to XXX_delay, XXX_count protected by
743	 * single lock above (split into XXX_lock if contention is an issue).
744	 */
745
746	/*
747	 * XXX_count is incremented on every XXX operation, the delay
748	 * associated with the operation is added to XXX_delay.
749	 * XXX_delay contains the accumulated delay time in nanoseconds.
750	 */
751	struct timespec blkio_start, blkio_end;	/* Shared by blkio, swapin */
752	u64 blkio_delay;	/* wait for sync block io completion */
753	u64 swapin_delay;	/* wait for swapin block io completion */
754	u32 blkio_count;	/* total count of the number of sync block */
755				/* io operations performed */
756	u32 swapin_count;	/* total count of the number of swapin block */
757				/* io operations performed */
758
759	struct timespec freepages_start, freepages_end;
760	u64 freepages_delay;	/* wait for memory reclaim */
761	u32 freepages_count;	/* total count of memory reclaim */
762};
763#endif	/* CONFIG_TASK_DELAY_ACCT */
764
765static inline int sched_info_on(void)
766{
767#ifdef CONFIG_SCHEDSTATS
768	return 1;
769#elif defined(CONFIG_TASK_DELAY_ACCT)
770	extern int delayacct_on;
771	return delayacct_on;
772#else
773	return 0;
774#endif
775}
776
777enum cpu_idle_type {
778	CPU_IDLE,
779	CPU_NOT_IDLE,
780	CPU_NEWLY_IDLE,
781	CPU_MAX_IDLE_TYPES
782};
783
784/*
785 * sched-domains (multiprocessor balancing) declarations:
786 */
787
788/*
789 * Increase resolution of nice-level calculations:
790 */
791#define SCHED_LOAD_SHIFT	10
792#define SCHED_LOAD_SCALE	(1L << SCHED_LOAD_SHIFT)
793
794#define SCHED_LOAD_SCALE_FUZZ	SCHED_LOAD_SCALE
795
796#ifdef CONFIG_SMP
797#define SD_LOAD_BALANCE		0x0001	/* Do load balancing on this domain. */
798#define SD_BALANCE_NEWIDLE	0x0002	/* Balance when about to become idle */
799#define SD_BALANCE_EXEC		0x0004	/* Balance on exec */
800#define SD_BALANCE_FORK		0x0008	/* Balance on fork, clone */
801#define SD_BALANCE_WAKE		0x0010  /* Balance on wakeup */
802#define SD_WAKE_AFFINE		0x0020	/* Wake task to waking CPU */
803#define SD_PREFER_LOCAL		0x0040  /* Prefer to keep tasks local to this domain */
804#define SD_SHARE_CPUPOWER	0x0080	/* Domain members share cpu power */
805#define SD_POWERSAVINGS_BALANCE	0x0100	/* Balance for power savings */
806#define SD_SHARE_PKG_RESOURCES	0x0200	/* Domain members share cpu pkg resources */
807#define SD_SERIALIZE		0x0400	/* Only a single load balancing instance */
808
809#define SD_PREFER_SIBLING	0x1000	/* Prefer to place tasks in a sibling domain */
810
811enum powersavings_balance_level {
812	POWERSAVINGS_BALANCE_NONE = 0,  /* No power saving load balance */
813	POWERSAVINGS_BALANCE_BASIC,	/* Fill one thread/core/package
814					 * first for long running threads
815					 */
816	POWERSAVINGS_BALANCE_WAKEUP,	/* Also bias task wakeups to semi-idle
817					 * cpu package for power savings
818					 */
819	MAX_POWERSAVINGS_BALANCE_LEVELS
820};
821
822extern int sched_mc_power_savings, sched_smt_power_savings;
823
824static inline int sd_balance_for_mc_power(void)
825{
826	if (sched_smt_power_savings)
827		return SD_POWERSAVINGS_BALANCE;
828
829	if (!sched_mc_power_savings)
830		return SD_PREFER_SIBLING;
831
832	return 0;
833}
834
835static inline int sd_balance_for_package_power(void)
836{
837	if (sched_mc_power_savings | sched_smt_power_savings)
838		return SD_POWERSAVINGS_BALANCE;
839
840	return SD_PREFER_SIBLING;
841}
842
843/*
844 * Optimise SD flags for power savings:
845 * SD_BALANCE_NEWIDLE helps agressive task consolidation and power savings.
846 * Keep default SD flags if sched_{smt,mc}_power_saving=0
847 */
848
849static inline int sd_power_saving_flags(void)
850{
851	if (sched_mc_power_savings | sched_smt_power_savings)
852		return SD_BALANCE_NEWIDLE;
853
854	return 0;
855}
856
857struct sched_group {
858	struct sched_group *next;	/* Must be a circular list */
859
860	/*
861	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
862	 * single CPU.
863	 */
864	unsigned int cpu_power;
865
866	/*
867	 * The CPUs this group covers.
868	 *
869	 * NOTE: this field is variable length. (Allocated dynamically
870	 * by attaching extra space to the end of the structure,
871	 * depending on how many CPUs the kernel has booted up with)
872	 *
873	 * It is also be embedded into static data structures at build
874	 * time. (See 'struct static_sched_group' in kernel/sched.c)
875	 */
876	unsigned long cpumask[0];
877};
878
879static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
880{
881	return to_cpumask(sg->cpumask);
882}
883
884enum sched_domain_level {
885	SD_LV_NONE = 0,
886	SD_LV_SIBLING,
887	SD_LV_MC,
888	SD_LV_CPU,
889	SD_LV_NODE,
890	SD_LV_ALLNODES,
891	SD_LV_MAX
892};
893
894struct sched_domain_attr {
895	int relax_domain_level;
896};
897
898#define SD_ATTR_INIT	(struct sched_domain_attr) {	\
899	.relax_domain_level = -1,			\
900}
901
902struct sched_domain {
903	/* These fields must be setup */
904	struct sched_domain *parent;	/* top domain must be null terminated */
905	struct sched_domain *child;	/* bottom domain must be null terminated */
906	struct sched_group *groups;	/* the balancing groups of the domain */
907	unsigned long min_interval;	/* Minimum balance interval ms */
908	unsigned long max_interval;	/* Maximum balance interval ms */
909	unsigned int busy_factor;	/* less balancing by factor if busy */
910	unsigned int imbalance_pct;	/* No balance until over watermark */
911	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
912	unsigned int busy_idx;
913	unsigned int idle_idx;
914	unsigned int newidle_idx;
915	unsigned int wake_idx;
916	unsigned int forkexec_idx;
917	unsigned int smt_gain;
918	int flags;			/* See SD_* */
919	enum sched_domain_level level;
920
921	/* Runtime fields. */
922	unsigned long last_balance;	/* init to jiffies. units in jiffies */
923	unsigned int balance_interval;	/* initialise to 1. units in ms. */
924	unsigned int nr_balance_failed; /* initialise to 0 */
925
926	u64 last_update;
927
928#ifdef CONFIG_SCHEDSTATS
929	/* load_balance() stats */
930	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
931	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
932	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
933	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
934	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
935	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
936	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
937	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
938
939	/* Active load balancing */
940	unsigned int alb_count;
941	unsigned int alb_failed;
942	unsigned int alb_pushed;
943
944	/* SD_BALANCE_EXEC stats */
945	unsigned int sbe_count;
946	unsigned int sbe_balanced;
947	unsigned int sbe_pushed;
948
949	/* SD_BALANCE_FORK stats */
950	unsigned int sbf_count;
951	unsigned int sbf_balanced;
952	unsigned int sbf_pushed;
953
954	/* try_to_wake_up() stats */
955	unsigned int ttwu_wake_remote;
956	unsigned int ttwu_move_affine;
957	unsigned int ttwu_move_balance;
958#endif
959#ifdef CONFIG_SCHED_DEBUG
960	char *name;
961#endif
962
963	unsigned int span_weight;
964	/*
965	 * Span of all CPUs in this domain.
966	 *
967	 * NOTE: this field is variable length. (Allocated dynamically
968	 * by attaching extra space to the end of the structure,
969	 * depending on how many CPUs the kernel has booted up with)
970	 *
971	 * It is also be embedded into static data structures at build
972	 * time. (See 'struct static_sched_domain' in kernel/sched.c)
973	 */
974	unsigned long span[0];
975};
976
977static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
978{
979	return to_cpumask(sd->span);
980}
981
982extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
983				    struct sched_domain_attr *dattr_new);
984
985/* Allocate an array of sched domains, for partition_sched_domains(). */
986cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
987void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
988
989/* Test a flag in parent sched domain */
990static inline int test_sd_parent(struct sched_domain *sd, int flag)
991{
992	if (sd->parent && (sd->parent->flags & flag))
993		return 1;
994
995	return 0;
996}
997
998unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu);
999unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu);
1000
1001#else /* CONFIG_SMP */
1002
1003struct sched_domain_attr;
1004
1005static inline void
1006partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1007			struct sched_domain_attr *dattr_new)
1008{
1009}
1010#endif	/* !CONFIG_SMP */
1011
1012
1013struct io_context;			/* See blkdev.h */
1014
1015
1016#ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1017extern void prefetch_stack(struct task_struct *t);
1018#else
1019static inline void prefetch_stack(struct task_struct *t) { }
1020#endif
1021
1022struct audit_context;		/* See audit.c */
1023struct mempolicy;
1024struct pipe_inode_info;
1025struct uts_namespace;
1026
1027struct rq;
1028struct sched_domain;
1029
1030/*
1031 * wake flags
1032 */
1033#define WF_SYNC		0x01		/* waker goes to sleep after wakup */
1034#define WF_FORK		0x02		/* child wakeup after fork */
1035
1036#define ENQUEUE_WAKEUP		1
1037#define ENQUEUE_WAKING		2
1038#define ENQUEUE_HEAD		4
1039
1040#define DEQUEUE_SLEEP		1
1041
1042struct sched_class {
1043	const struct sched_class *next;
1044
1045	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1046	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1047	void (*yield_task) (struct rq *rq);
1048
1049	void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
1050
1051	struct task_struct * (*pick_next_task) (struct rq *rq);
1052	void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1053
1054#ifdef CONFIG_SMP
1055	int  (*select_task_rq)(struct rq *rq, struct task_struct *p,
1056			       int sd_flag, int flags);
1057
1058	void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
1059	void (*post_schedule) (struct rq *this_rq);
1060	void (*task_waking) (struct rq *this_rq, struct task_struct *task);
1061	void (*task_woken) (struct rq *this_rq, struct task_struct *task);
1062
1063	void (*set_cpus_allowed)(struct task_struct *p,
1064				 const struct cpumask *newmask);
1065
1066	void (*rq_online)(struct rq *rq);
1067	void (*rq_offline)(struct rq *rq);
1068#endif
1069
1070	void (*set_curr_task) (struct rq *rq);
1071	void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1072	void (*task_fork) (struct task_struct *p);
1073
1074	void (*switched_from) (struct rq *this_rq, struct task_struct *task,
1075			       int running);
1076	void (*switched_to) (struct rq *this_rq, struct task_struct *task,
1077			     int running);
1078	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1079			     int oldprio, int running);
1080
1081	unsigned int (*get_rr_interval) (struct rq *rq,
1082					 struct task_struct *task);
1083
1084#ifdef CONFIG_FAIR_GROUP_SCHED
1085	void (*moved_group) (struct task_struct *p, int on_rq);
1086#endif
1087};
1088
1089struct load_weight {
1090	unsigned long weight, inv_weight;
1091};
1092
1093#ifdef CONFIG_SCHEDSTATS
1094struct sched_statistics {
1095	u64			wait_start;
1096	u64			wait_max;
1097	u64			wait_count;
1098	u64			wait_sum;
1099	u64			iowait_count;
1100	u64			iowait_sum;
1101
1102	u64			sleep_start;
1103	u64			sleep_max;
1104	s64			sum_sleep_runtime;
1105
1106	u64			block_start;
1107	u64			block_max;
1108	u64			exec_max;
1109	u64			slice_max;
1110
1111	u64			nr_migrations_cold;
1112	u64			nr_failed_migrations_affine;
1113	u64			nr_failed_migrations_running;
1114	u64			nr_failed_migrations_hot;
1115	u64			nr_forced_migrations;
1116
1117	u64			nr_wakeups;
1118	u64			nr_wakeups_sync;
1119	u64			nr_wakeups_migrate;
1120	u64			nr_wakeups_local;
1121	u64			nr_wakeups_remote;
1122	u64			nr_wakeups_affine;
1123	u64			nr_wakeups_affine_attempts;
1124	u64			nr_wakeups_passive;
1125	u64			nr_wakeups_idle;
1126};
1127#endif
1128
1129struct sched_entity {
1130	struct load_weight	load;		/* for load-balancing */
1131	struct rb_node		run_node;
1132	struct list_head	group_node;
1133	unsigned int		on_rq;
1134
1135	u64			exec_start;
1136	u64			sum_exec_runtime;
1137	u64			vruntime;
1138	u64			prev_sum_exec_runtime;
1139
1140	u64			nr_migrations;
1141
1142#ifdef CONFIG_SCHEDSTATS
1143	struct sched_statistics statistics;
1144#endif
1145
1146#ifdef CONFIG_FAIR_GROUP_SCHED
1147	struct sched_entity	*parent;
1148	/* rq on which this entity is (to be) queued: */
1149	struct cfs_rq		*cfs_rq;
1150	/* rq "owned" by this entity/group: */
1151	struct cfs_rq		*my_q;
1152#endif
1153};
1154
1155struct sched_rt_entity {
1156	struct list_head run_list;
1157	unsigned long timeout;
1158	unsigned int time_slice;
1159	int nr_cpus_allowed;
1160
1161	struct sched_rt_entity *back;
1162#ifdef CONFIG_RT_GROUP_SCHED
1163	struct sched_rt_entity	*parent;
1164	/* rq on which this entity is (to be) queued: */
1165	struct rt_rq		*rt_rq;
1166	/* rq "owned" by this entity/group: */
1167	struct rt_rq		*my_q;
1168#endif
1169};
1170
1171struct rcu_node;
1172
1173struct task_struct {
1174	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
1175	void *stack;
1176	atomic_t usage;
1177	unsigned int flags;	/* per process flags, defined below */
1178	unsigned int ptrace;
1179
1180	int lock_depth;		/* BKL lock depth */
1181
1182#ifdef CONFIG_SMP
1183#ifdef __ARCH_WANT_UNLOCKED_CTXSW
1184	int oncpu;
1185#endif
1186#endif
1187
1188	int prio, static_prio, normal_prio;
1189	unsigned int rt_priority;
1190	const struct sched_class *sched_class;
1191	struct sched_entity se;
1192	struct sched_rt_entity rt;
1193
1194#ifdef CONFIG_PREEMPT_NOTIFIERS
1195	/* list of struct preempt_notifier: */
1196	struct hlist_head preempt_notifiers;
1197#endif
1198
1199	/*
1200	 * fpu_counter contains the number of consecutive context switches
1201	 * that the FPU is used. If this is over a threshold, the lazy fpu
1202	 * saving becomes unlazy to save the trap. This is an unsigned char
1203	 * so that after 256 times the counter wraps and the behavior turns
1204	 * lazy again; this to deal with bursty apps that only use FPU for
1205	 * a short time
1206	 */
1207	unsigned char fpu_counter;
1208#ifdef CONFIG_BLK_DEV_IO_TRACE
1209	unsigned int btrace_seq;
1210#endif
1211
1212	unsigned int policy;
1213	cpumask_t cpus_allowed;
1214
1215#ifdef CONFIG_TREE_PREEMPT_RCU
1216	int rcu_read_lock_nesting;
1217	char rcu_read_unlock_special;
1218	struct rcu_node *rcu_blocked_node;
1219	struct list_head rcu_node_entry;
1220#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1221
1222#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1223	struct sched_info sched_info;
1224#endif
1225
1226	struct list_head tasks;
1227	struct plist_node pushable_tasks;
1228
1229	struct mm_struct *mm, *active_mm;
1230#if defined(SPLIT_RSS_COUNTING)
1231	struct task_rss_stat	rss_stat;
1232#endif
1233/* task state */
1234	int exit_state;
1235	int exit_code, exit_signal;
1236	int pdeath_signal;  /*  The signal sent when the parent dies  */
1237	/* ??? */
1238	unsigned int personality;
1239	unsigned did_exec:1;
1240	unsigned in_execve:1;	/* Tell the LSMs that the process is doing an
1241				 * execve */
1242	unsigned in_iowait:1;
1243
1244
1245	/* Revert to default priority/policy when forking */
1246	unsigned sched_reset_on_fork:1;
1247
1248	pid_t pid;
1249	pid_t tgid;
1250
1251#ifdef CONFIG_CC_STACKPROTECTOR
1252	/* Canary value for the -fstack-protector gcc feature */
1253	unsigned long stack_canary;
1254#endif
1255
1256	/*
1257	 * pointers to (original) parent process, youngest child, younger sibling,
1258	 * older sibling, respectively.  (p->father can be replaced with
1259	 * p->real_parent->pid)
1260	 */
1261	struct task_struct *real_parent; /* real parent process */
1262	struct task_struct *parent; /* recipient of SIGCHLD, wait4() reports */
1263	/*
1264	 * children/sibling forms the list of my natural children
1265	 */
1266	struct list_head children;	/* list of my children */
1267	struct list_head sibling;	/* linkage in my parent's children list */
1268	struct task_struct *group_leader;	/* threadgroup leader */
1269
1270	/*
1271	 * ptraced is the list of tasks this task is using ptrace on.
1272	 * This includes both natural children and PTRACE_ATTACH targets.
1273	 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1274	 */
1275	struct list_head ptraced;
1276	struct list_head ptrace_entry;
1277
1278	/*
1279	 * This is the tracer handle for the ptrace BTS extension.
1280	 * This field actually belongs to the ptracer task.
1281	 */
1282	struct bts_context *bts;
1283
1284	/* PID/PID hash table linkage. */
1285	struct pid_link pids[PIDTYPE_MAX];
1286	struct list_head thread_group;
1287
1288	struct completion *vfork_done;		/* for vfork() */
1289	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
1290	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
1291
1292	cputime_t utime, stime, utimescaled, stimescaled;
1293	cputime_t gtime;
1294#ifndef CONFIG_VIRT_CPU_ACCOUNTING
1295	cputime_t prev_utime, prev_stime;
1296#endif
1297	unsigned long nvcsw, nivcsw; /* context switch counts */
1298	struct timespec start_time; 		/* monotonic time */
1299	struct timespec real_start_time;	/* boot based time */
1300/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1301	unsigned long min_flt, maj_flt;
1302
1303	struct task_cputime cputime_expires;
1304	struct list_head cpu_timers[3];
1305
1306/* process credentials */
1307	const struct cred *real_cred;	/* objective and real subjective task
1308					 * credentials (COW) */
1309	const struct cred *cred;	/* effective (overridable) subjective task
1310					 * credentials (COW) */
1311	struct mutex cred_guard_mutex;	/* guard against foreign influences on
1312					 * credential calculations
1313					 * (notably. ptrace) */
1314	struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */
1315
1316	char comm[TASK_COMM_LEN]; /* executable name excluding path
1317				     - access with [gs]et_task_comm (which lock
1318				       it with task_lock())
1319				     - initialized normally by setup_new_exec */
1320/* file system info */
1321	int link_count, total_link_count;
1322#ifdef CONFIG_SYSVIPC
1323/* ipc stuff */
1324	struct sysv_sem sysvsem;
1325#endif
1326#ifdef CONFIG_DETECT_HUNG_TASK
1327/* hung task detection */
1328	unsigned long last_switch_count;
1329#endif
1330/* CPU-specific state of this task */
1331	struct thread_struct thread;
1332/* filesystem information */
1333	struct fs_struct *fs;
1334/* open file information */
1335	struct files_struct *files;
1336/* namespaces */
1337	struct nsproxy *nsproxy;
1338/* signal handlers */
1339	struct signal_struct *signal;
1340	struct sighand_struct *sighand;
1341
1342	sigset_t blocked, real_blocked;
1343	sigset_t saved_sigmask;	/* restored if set_restore_sigmask() was used */
1344	struct sigpending pending;
1345
1346	unsigned long sas_ss_sp;
1347	size_t sas_ss_size;
1348	int (*notifier)(void *priv);
1349	void *notifier_data;
1350	sigset_t *notifier_mask;
1351	struct audit_context *audit_context;
1352#ifdef CONFIG_AUDITSYSCALL
1353	uid_t loginuid;
1354	unsigned int sessionid;
1355#endif
1356	seccomp_t seccomp;
1357
1358/* Thread group tracking */
1359   	u32 parent_exec_id;
1360   	u32 self_exec_id;
1361/* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1362 * mempolicy */
1363	spinlock_t alloc_lock;
1364
1365#ifdef CONFIG_GENERIC_HARDIRQS
1366	/* IRQ handler threads */
1367	struct irqaction *irqaction;
1368#endif
1369
1370	/* Protection of the PI data structures: */
1371	raw_spinlock_t pi_lock;
1372
1373#ifdef CONFIG_RT_MUTEXES
1374	/* PI waiters blocked on a rt_mutex held by this task */
1375	struct plist_head pi_waiters;
1376	/* Deadlock detection and priority inheritance handling */
1377	struct rt_mutex_waiter *pi_blocked_on;
1378#endif
1379
1380#ifdef CONFIG_DEBUG_MUTEXES
1381	/* mutex deadlock detection */
1382	struct mutex_waiter *blocked_on;
1383#endif
1384#ifdef CONFIG_TRACE_IRQFLAGS
1385	unsigned int irq_events;
1386	unsigned long hardirq_enable_ip;
1387	unsigned long hardirq_disable_ip;
1388	unsigned int hardirq_enable_event;
1389	unsigned int hardirq_disable_event;
1390	int hardirqs_enabled;
1391	int hardirq_context;
1392	unsigned long softirq_disable_ip;
1393	unsigned long softirq_enable_ip;
1394	unsigned int softirq_disable_event;
1395	unsigned int softirq_enable_event;
1396	int softirqs_enabled;
1397	int softirq_context;
1398#endif
1399#ifdef CONFIG_LOCKDEP
1400# define MAX_LOCK_DEPTH 48UL
1401	u64 curr_chain_key;
1402	int lockdep_depth;
1403	unsigned int lockdep_recursion;
1404	struct held_lock held_locks[MAX_LOCK_DEPTH];
1405	gfp_t lockdep_reclaim_gfp;
1406#endif
1407
1408/* journalling filesystem info */
1409	void *journal_info;
1410
1411/* stacked block device info */
1412	struct bio_list *bio_list;
1413
1414/* VM state */
1415	struct reclaim_state *reclaim_state;
1416
1417	struct backing_dev_info *backing_dev_info;
1418
1419	struct io_context *io_context;
1420
1421	unsigned long ptrace_message;
1422	siginfo_t *last_siginfo; /* For ptrace use.  */
1423	struct task_io_accounting ioac;
1424#if defined(CONFIG_TASK_XACCT)
1425	u64 acct_rss_mem1;	/* accumulated rss usage */
1426	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1427	cputime_t acct_timexpd;	/* stime + utime since last update */
1428#endif
1429#ifdef CONFIG_CPUSETS
1430	nodemask_t mems_allowed;	/* Protected by alloc_lock */
1431	int cpuset_mem_spread_rotor;
1432#endif
1433#ifdef CONFIG_CGROUPS
1434	/* Control Group info protected by css_set_lock */
1435	struct css_set *cgroups;
1436	/* cg_list protected by css_set_lock and tsk->alloc_lock */
1437	struct list_head cg_list;
1438#endif
1439#ifdef CONFIG_FUTEX
1440	struct robust_list_head __user *robust_list;
1441#ifdef CONFIG_COMPAT
1442	struct compat_robust_list_head __user *compat_robust_list;
1443#endif
1444	struct list_head pi_state_list;
1445	struct futex_pi_state *pi_state_cache;
1446#endif
1447#ifdef CONFIG_PERF_EVENTS
1448	struct perf_event_context *perf_event_ctxp;
1449	struct mutex perf_event_mutex;
1450	struct list_head perf_event_list;
1451#endif
1452#ifdef CONFIG_NUMA
1453	struct mempolicy *mempolicy;	/* Protected by alloc_lock */
1454	short il_next;
1455#endif
1456	atomic_t fs_excl;	/* holding fs exclusive resources */
1457	struct rcu_head rcu;
1458
1459	/*
1460	 * cache last used pipe for splice
1461	 */
1462	struct pipe_inode_info *splice_pipe;
1463#ifdef	CONFIG_TASK_DELAY_ACCT
1464	struct task_delay_info *delays;
1465#endif
1466#ifdef CONFIG_FAULT_INJECTION
1467	int make_it_fail;
1468#endif
1469	struct prop_local_single dirties;
1470#ifdef CONFIG_LATENCYTOP
1471	int latency_record_count;
1472	struct latency_record latency_record[LT_SAVECOUNT];
1473#endif
1474	/*
1475	 * time slack values; these are used to round up poll() and
1476	 * select() etc timeout values. These are in nanoseconds.
1477	 */
1478	unsigned long timer_slack_ns;
1479	unsigned long default_timer_slack_ns;
1480
1481	struct list_head	*scm_work_list;
1482#ifdef CONFIG_FUNCTION_GRAPH_TRACER
1483	/* Index of current stored address in ret_stack */
1484	int curr_ret_stack;
1485	/* Stack of return addresses for return function tracing */
1486	struct ftrace_ret_stack	*ret_stack;
1487	/* time stamp for last schedule */
1488	unsigned long long ftrace_timestamp;
1489	/*
1490	 * Number of functions that haven't been traced
1491	 * because of depth overrun.
1492	 */
1493	atomic_t trace_overrun;
1494	/* Pause for the tracing */
1495	atomic_t tracing_graph_pause;
1496#endif
1497#ifdef CONFIG_TRACING
1498	/* state flags for use by tracers */
1499	unsigned long trace;
1500	/* bitmask of trace recursion */
1501	unsigned long trace_recursion;
1502#endif /* CONFIG_TRACING */
1503	unsigned long stack_start;
1504#ifdef CONFIG_CGROUP_MEM_RES_CTLR /* memcg uses this to do batch job */
1505	struct memcg_batch_info {
1506		int do_batch;	/* incremented when batch uncharge started */
1507		struct mem_cgroup *memcg; /* target memcg of uncharge */
1508		unsigned long bytes; 		/* uncharged usage */
1509		unsigned long memsw_bytes; /* uncharged mem+swap usage */
1510	} memcg_batch;
1511#endif
1512};
1513
1514/* Future-safe accessor for struct task_struct's cpus_allowed. */
1515#define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1516
1517/*
1518 * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1519 * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1520 * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1521 * values are inverted: lower p->prio value means higher priority.
1522 *
1523 * The MAX_USER_RT_PRIO value allows the actual maximum
1524 * RT priority to be separate from the value exported to
1525 * user-space.  This allows kernel threads to set their
1526 * priority to a value higher than any user task. Note:
1527 * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1528 */
1529
1530#define MAX_USER_RT_PRIO	100
1531#define MAX_RT_PRIO		MAX_USER_RT_PRIO
1532
1533#define MAX_PRIO		(MAX_RT_PRIO + 40)
1534#define DEFAULT_PRIO		(MAX_RT_PRIO + 20)
1535
1536static inline int rt_prio(int prio)
1537{
1538	if (unlikely(prio < MAX_RT_PRIO))
1539		return 1;
1540	return 0;
1541}
1542
1543static inline int rt_task(struct task_struct *p)
1544{
1545	return rt_prio(p->prio);
1546}
1547
1548static inline struct pid *task_pid(struct task_struct *task)
1549{
1550	return task->pids[PIDTYPE_PID].pid;
1551}
1552
1553static inline struct pid *task_tgid(struct task_struct *task)
1554{
1555	return task->group_leader->pids[PIDTYPE_PID].pid;
1556}
1557
1558/*
1559 * Without tasklist or rcu lock it is not safe to dereference
1560 * the result of task_pgrp/task_session even if task == current,
1561 * we can race with another thread doing sys_setsid/sys_setpgid.
1562 */
1563static inline struct pid *task_pgrp(struct task_struct *task)
1564{
1565	return task->group_leader->pids[PIDTYPE_PGID].pid;
1566}
1567
1568static inline struct pid *task_session(struct task_struct *task)
1569{
1570	return task->group_leader->pids[PIDTYPE_SID].pid;
1571}
1572
1573struct pid_namespace;
1574
1575/*
1576 * the helpers to get the task's different pids as they are seen
1577 * from various namespaces
1578 *
1579 * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1580 * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1581 *                     current.
1582 * task_xid_nr_ns()  : id seen from the ns specified;
1583 *
1584 * set_task_vxid()   : assigns a virtual id to a task;
1585 *
1586 * see also pid_nr() etc in include/linux/pid.h
1587 */
1588pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1589			struct pid_namespace *ns);
1590
1591static inline pid_t task_pid_nr(struct task_struct *tsk)
1592{
1593	return tsk->pid;
1594}
1595
1596static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1597					struct pid_namespace *ns)
1598{
1599	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1600}
1601
1602static inline pid_t task_pid_vnr(struct task_struct *tsk)
1603{
1604	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1605}
1606
1607
1608static inline pid_t task_tgid_nr(struct task_struct *tsk)
1609{
1610	return tsk->tgid;
1611}
1612
1613pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1614
1615static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1616{
1617	return pid_vnr(task_tgid(tsk));
1618}
1619
1620
1621static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1622					struct pid_namespace *ns)
1623{
1624	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1625}
1626
1627static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1628{
1629	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1630}
1631
1632
1633static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1634					struct pid_namespace *ns)
1635{
1636	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1637}
1638
1639static inline pid_t task_session_vnr(struct task_struct *tsk)
1640{
1641	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1642}
1643
1644/* obsolete, do not use */
1645static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1646{
1647	return task_pgrp_nr_ns(tsk, &init_pid_ns);
1648}
1649
1650/**
1651 * pid_alive - check that a task structure is not stale
1652 * @p: Task structure to be checked.
1653 *
1654 * Test if a process is not yet dead (at most zombie state)
1655 * If pid_alive fails, then pointers within the task structure
1656 * can be stale and must not be dereferenced.
1657 */
1658static inline int pid_alive(struct task_struct *p)
1659{
1660	return p->pids[PIDTYPE_PID].pid != NULL;
1661}
1662
1663/**
1664 * is_global_init - check if a task structure is init
1665 * @tsk: Task structure to be checked.
1666 *
1667 * Check if a task structure is the first user space task the kernel created.
1668 */
1669static inline int is_global_init(struct task_struct *tsk)
1670{
1671	return tsk->pid == 1;
1672}
1673
1674/*
1675 * is_container_init:
1676 * check whether in the task is init in its own pid namespace.
1677 */
1678extern int is_container_init(struct task_struct *tsk);
1679
1680extern struct pid *cad_pid;
1681
1682extern void free_task(struct task_struct *tsk);
1683#define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1684
1685extern void __put_task_struct(struct task_struct *t);
1686
1687static inline void put_task_struct(struct task_struct *t)
1688{
1689	if (atomic_dec_and_test(&t->usage))
1690		__put_task_struct(t);
1691}
1692
1693extern void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1694extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1695
1696/*
1697 * Per process flags
1698 */
1699#define PF_ALIGNWARN	0x00000001	/* Print alignment warning msgs */
1700					/* Not implemented yet, only for 486*/
1701#define PF_STARTING	0x00000002	/* being created */
1702#define PF_EXITING	0x00000004	/* getting shut down */
1703#define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
1704#define PF_VCPU		0x00000010	/* I'm a virtual CPU */
1705#define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
1706#define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
1707#define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
1708#define PF_DUMPCORE	0x00000200	/* dumped core */
1709#define PF_SIGNALED	0x00000400	/* killed by a signal */
1710#define PF_MEMALLOC	0x00000800	/* Allocating memory */
1711#define PF_FLUSHER	0x00001000	/* responsible for disk writeback */
1712#define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
1713#define PF_FREEZING	0x00004000	/* freeze in progress. do not account to load */
1714#define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
1715#define PF_FROZEN	0x00010000	/* frozen for system suspend */
1716#define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
1717#define PF_KSWAPD	0x00040000	/* I am kswapd */
1718#define PF_OOM_ORIGIN	0x00080000	/* Allocating much memory to others */
1719#define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
1720#define PF_KTHREAD	0x00200000	/* I am a kernel thread */
1721#define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
1722#define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
1723#define PF_SPREAD_PAGE	0x01000000	/* Spread page cache over cpuset */
1724#define PF_SPREAD_SLAB	0x02000000	/* Spread some slab caches over cpuset */
1725#define PF_THREAD_BOUND	0x04000000	/* Thread bound to specific cpu */
1726#define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
1727#define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
1728#define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
1729#define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezeable */
1730#define PF_FREEZER_NOSIG 0x80000000	/* Freezer won't send signals to it */
1731
1732/*
1733 * Only the _current_ task can read/write to tsk->flags, but other
1734 * tasks can access tsk->flags in readonly mode for example
1735 * with tsk_used_math (like during threaded core dumping).
1736 * There is however an exception to this rule during ptrace
1737 * or during fork: the ptracer task is allowed to write to the
1738 * child->flags of its traced child (same goes for fork, the parent
1739 * can write to the child->flags), because we're guaranteed the
1740 * child is not running and in turn not changing child->flags
1741 * at the same time the parent does it.
1742 */
1743#define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1744#define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1745#define clear_used_math() clear_stopped_child_used_math(current)
1746#define set_used_math() set_stopped_child_used_math(current)
1747#define conditional_stopped_child_used_math(condition, child) \
1748	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1749#define conditional_used_math(condition) \
1750	conditional_stopped_child_used_math(condition, current)
1751#define copy_to_stopped_child_used_math(child) \
1752	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1753/* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1754#define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1755#define used_math() tsk_used_math(current)
1756
1757#ifdef CONFIG_TREE_PREEMPT_RCU
1758
1759#define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */
1760#define RCU_READ_UNLOCK_NEED_QS (1 << 1) /* RCU core needs CPU response. */
1761
1762static inline void rcu_copy_process(struct task_struct *p)
1763{
1764	p->rcu_read_lock_nesting = 0;
1765	p->rcu_read_unlock_special = 0;
1766	p->rcu_blocked_node = NULL;
1767	INIT_LIST_HEAD(&p->rcu_node_entry);
1768}
1769
1770#else
1771
1772static inline void rcu_copy_process(struct task_struct *p)
1773{
1774}
1775
1776#endif
1777
1778#ifdef CONFIG_SMP
1779extern int set_cpus_allowed_ptr(struct task_struct *p,
1780				const struct cpumask *new_mask);
1781#else
1782static inline int set_cpus_allowed_ptr(struct task_struct *p,
1783				       const struct cpumask *new_mask)
1784{
1785	if (!cpumask_test_cpu(0, new_mask))
1786		return -EINVAL;
1787	return 0;
1788}
1789#endif
1790
1791#ifndef CONFIG_CPUMASK_OFFSTACK
1792static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1793{
1794	return set_cpus_allowed_ptr(p, &new_mask);
1795}
1796#endif
1797
1798/*
1799 * Architectures can set this to 1 if they have specified
1800 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
1801 * but then during bootup it turns out that sched_clock()
1802 * is reliable after all:
1803 */
1804#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1805extern int sched_clock_stable;
1806#endif
1807
1808/* ftrace calls sched_clock() directly */
1809extern unsigned long long notrace sched_clock(void);
1810
1811extern void sched_clock_init(void);
1812extern u64 sched_clock_cpu(int cpu);
1813
1814#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1815static inline void sched_clock_tick(void)
1816{
1817}
1818
1819static inline void sched_clock_idle_sleep_event(void)
1820{
1821}
1822
1823static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
1824{
1825}
1826#else
1827extern void sched_clock_tick(void);
1828extern void sched_clock_idle_sleep_event(void);
1829extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1830#endif
1831
1832/*
1833 * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
1834 * clock constructed from sched_clock():
1835 */
1836extern unsigned long long cpu_clock(int cpu);
1837
1838extern unsigned long long
1839task_sched_runtime(struct task_struct *task);
1840extern unsigned long long thread_group_sched_runtime(struct task_struct *task);
1841
1842/* sched_exec is called by processes performing an exec */
1843#ifdef CONFIG_SMP
1844extern void sched_exec(void);
1845#else
1846#define sched_exec()   {}
1847#endif
1848
1849extern void sched_clock_idle_sleep_event(void);
1850extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1851
1852#ifdef CONFIG_HOTPLUG_CPU
1853extern void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p);
1854extern void idle_task_exit(void);
1855#else
1856static inline void idle_task_exit(void) {}
1857#endif
1858
1859extern void sched_idle_next(void);
1860
1861#if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1862extern void wake_up_idle_cpu(int cpu);
1863#else
1864static inline void wake_up_idle_cpu(int cpu) { }
1865#endif
1866
1867extern unsigned int sysctl_sched_latency;
1868extern unsigned int sysctl_sched_min_granularity;
1869extern unsigned int sysctl_sched_wakeup_granularity;
1870extern unsigned int sysctl_sched_shares_ratelimit;
1871extern unsigned int sysctl_sched_shares_thresh;
1872extern unsigned int sysctl_sched_child_runs_first;
1873
1874enum sched_tunable_scaling {
1875	SCHED_TUNABLESCALING_NONE,
1876	SCHED_TUNABLESCALING_LOG,
1877	SCHED_TUNABLESCALING_LINEAR,
1878	SCHED_TUNABLESCALING_END,
1879};
1880extern enum sched_tunable_scaling sysctl_sched_tunable_scaling;
1881
1882#ifdef CONFIG_SCHED_DEBUG
1883extern unsigned int sysctl_sched_migration_cost;
1884extern unsigned int sysctl_sched_nr_migrate;
1885extern unsigned int sysctl_sched_time_avg;
1886extern unsigned int sysctl_timer_migration;
1887
1888int sched_proc_update_handler(struct ctl_table *table, int write,
1889		void __user *buffer, size_t *length,
1890		loff_t *ppos);
1891#endif
1892#ifdef CONFIG_SCHED_DEBUG
1893static inline unsigned int get_sysctl_timer_migration(void)
1894{
1895	return sysctl_timer_migration;
1896}
1897#else
1898static inline unsigned int get_sysctl_timer_migration(void)
1899{
1900	return 1;
1901}
1902#endif
1903extern unsigned int sysctl_sched_rt_period;
1904extern int sysctl_sched_rt_runtime;
1905
1906int sched_rt_handler(struct ctl_table *table, int write,
1907		void __user *buffer, size_t *lenp,
1908		loff_t *ppos);
1909
1910extern unsigned int sysctl_sched_compat_yield;
1911
1912#ifdef CONFIG_RT_MUTEXES
1913extern int rt_mutex_getprio(struct task_struct *p);
1914extern void rt_mutex_setprio(struct task_struct *p, int prio);
1915extern void rt_mutex_adjust_pi(struct task_struct *p);
1916#else
1917static inline int rt_mutex_getprio(struct task_struct *p)
1918{
1919	return p->normal_prio;
1920}
1921# define rt_mutex_adjust_pi(p)		do { } while (0)
1922#endif
1923
1924extern void set_user_nice(struct task_struct *p, long nice);
1925extern int task_prio(const struct task_struct *p);
1926extern int task_nice(const struct task_struct *p);
1927extern int can_nice(const struct task_struct *p, const int nice);
1928extern int task_curr(const struct task_struct *p);
1929extern int idle_cpu(int cpu);
1930extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1931extern int sched_setscheduler_nocheck(struct task_struct *, int,
1932				      struct sched_param *);
1933extern struct task_struct *idle_task(int cpu);
1934extern struct task_struct *curr_task(int cpu);
1935extern void set_curr_task(int cpu, struct task_struct *p);
1936
1937void yield(void);
1938
1939/*
1940 * The default (Linux) execution domain.
1941 */
1942extern struct exec_domain	default_exec_domain;
1943
1944union thread_union {
1945	struct thread_info thread_info;
1946	unsigned long stack[THREAD_SIZE/sizeof(long)];
1947};
1948
1949#ifndef __HAVE_ARCH_KSTACK_END
1950static inline int kstack_end(void *addr)
1951{
1952	/* Reliable end of stack detection:
1953	 * Some APM bios versions misalign the stack
1954	 */
1955	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1956}
1957#endif
1958
1959extern union thread_union init_thread_union;
1960extern struct task_struct init_task;
1961
1962extern struct   mm_struct init_mm;
1963
1964extern struct pid_namespace init_pid_ns;
1965
1966/*
1967 * find a task by one of its numerical ids
1968 *
1969 * find_task_by_pid_ns():
1970 *      finds a task by its pid in the specified namespace
1971 * find_task_by_vpid():
1972 *      finds a task by its virtual pid
1973 *
1974 * see also find_vpid() etc in include/linux/pid.h
1975 */
1976
1977extern struct task_struct *find_task_by_vpid(pid_t nr);
1978extern struct task_struct *find_task_by_pid_ns(pid_t nr,
1979		struct pid_namespace *ns);
1980
1981extern void __set_special_pids(struct pid *pid);
1982
1983/* per-UID process charging. */
1984extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
1985static inline struct user_struct *get_uid(struct user_struct *u)
1986{
1987	atomic_inc(&u->__count);
1988	return u;
1989}
1990extern void free_uid(struct user_struct *);
1991extern void release_uids(struct user_namespace *ns);
1992
1993#include <asm/current.h>
1994
1995extern void do_timer(unsigned long ticks);
1996
1997extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1998extern int wake_up_process(struct task_struct *tsk);
1999extern void wake_up_new_task(struct task_struct *tsk,
2000				unsigned long clone_flags);
2001#ifdef CONFIG_SMP
2002 extern void kick_process(struct task_struct *tsk);
2003#else
2004 static inline void kick_process(struct task_struct *tsk) { }
2005#endif
2006extern void sched_fork(struct task_struct *p, int clone_flags);
2007extern void sched_dead(struct task_struct *p);
2008
2009extern void proc_caches_init(void);
2010extern void flush_signals(struct task_struct *);
2011extern void __flush_signals(struct task_struct *);
2012extern void ignore_signals(struct task_struct *);
2013extern void flush_signal_handlers(struct task_struct *, int force_default);
2014extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2015
2016static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
2017{
2018	unsigned long flags;
2019	int ret;
2020
2021	spin_lock_irqsave(&tsk->sighand->siglock, flags);
2022	ret = dequeue_signal(tsk, mask, info);
2023	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
2024
2025	return ret;
2026}
2027
2028extern void block_all_signals(int (*notifier)(void *priv), void *priv,
2029			      sigset_t *mask);
2030extern void unblock_all_signals(void);
2031extern void release_task(struct task_struct * p);
2032extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2033extern int force_sigsegv(int, struct task_struct *);
2034extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2035extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2036extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2037extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
2038extern int kill_pgrp(struct pid *pid, int sig, int priv);
2039extern int kill_pid(struct pid *pid, int sig, int priv);
2040extern int kill_proc_info(int, struct siginfo *, pid_t);
2041extern int do_notify_parent(struct task_struct *, int);
2042extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2043extern void force_sig(int, struct task_struct *);
2044extern int send_sig(int, struct task_struct *, int);
2045extern void zap_other_threads(struct task_struct *p);
2046extern struct sigqueue *sigqueue_alloc(void);
2047extern void sigqueue_free(struct sigqueue *);
2048extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
2049extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2050extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
2051
2052static inline int kill_cad_pid(int sig, int priv)
2053{
2054	return kill_pid(cad_pid, sig, priv);
2055}
2056
2057/* These can be the second arg to send_sig_info/send_group_sig_info.  */
2058#define SEND_SIG_NOINFO ((struct siginfo *) 0)
2059#define SEND_SIG_PRIV	((struct siginfo *) 1)
2060#define SEND_SIG_FORCED	((struct siginfo *) 2)
2061
2062/*
2063 * True if we are on the alternate signal stack.
2064 */
2065static inline int on_sig_stack(unsigned long sp)
2066{
2067#ifdef CONFIG_STACK_GROWSUP
2068	return sp >= current->sas_ss_sp &&
2069		sp - current->sas_ss_sp < current->sas_ss_size;
2070#else
2071	return sp > current->sas_ss_sp &&
2072		sp - current->sas_ss_sp <= current->sas_ss_size;
2073#endif
2074}
2075
2076static inline int sas_ss_flags(unsigned long sp)
2077{
2078	return (current->sas_ss_size == 0 ? SS_DISABLE
2079		: on_sig_stack(sp) ? SS_ONSTACK : 0);
2080}
2081
2082/*
2083 * Routines for handling mm_structs
2084 */
2085extern struct mm_struct * mm_alloc(void);
2086
2087/* mmdrop drops the mm and the page tables */
2088extern void __mmdrop(struct mm_struct *);
2089static inline void mmdrop(struct mm_struct * mm)
2090{
2091	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2092		__mmdrop(mm);
2093}
2094
2095/* mmput gets rid of the mappings and all user-space */
2096extern void mmput(struct mm_struct *);
2097/* Grab a reference to a task's mm, if it is not already going away */
2098extern struct mm_struct *get_task_mm(struct task_struct *task);
2099/* Remove the current tasks stale references to the old mm_struct */
2100extern void mm_release(struct task_struct *, struct mm_struct *);
2101/* Allocate a new mm structure and copy contents from tsk->mm */
2102extern struct mm_struct *dup_mm(struct task_struct *tsk);
2103
2104extern int copy_thread(unsigned long, unsigned long, unsigned long,
2105			struct task_struct *, struct pt_regs *);
2106extern void flush_thread(void);
2107extern void exit_thread(void);
2108
2109extern void exit_files(struct task_struct *);
2110extern void __cleanup_signal(struct signal_struct *);
2111extern void __cleanup_sighand(struct sighand_struct *);
2112
2113extern void exit_itimers(struct signal_struct *);
2114extern void flush_itimer_signals(void);
2115
2116extern NORET_TYPE void do_group_exit(int);
2117
2118extern void daemonize(const char *, ...);
2119extern int allow_signal(int);
2120extern int disallow_signal(int);
2121
2122extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
2123extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
2124struct task_struct *fork_idle(int);
2125
2126extern void set_task_comm(struct task_struct *tsk, char *from);
2127extern char *get_task_comm(char *to, struct task_struct *tsk);
2128
2129#ifdef CONFIG_SMP
2130extern void wait_task_context_switch(struct task_struct *p);
2131extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2132#else
2133static inline void wait_task_context_switch(struct task_struct *p) {}
2134static inline unsigned long wait_task_inactive(struct task_struct *p,
2135					       long match_state)
2136{
2137	return 1;
2138}
2139#endif
2140
2141#define next_task(p) \
2142	list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2143
2144#define for_each_process(p) \
2145	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2146
2147extern bool current_is_single_threaded(void);
2148
2149/*
2150 * Careful: do_each_thread/while_each_thread is a double loop so
2151 *          'break' will not work as expected - use goto instead.
2152 */
2153#define do_each_thread(g, t) \
2154	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2155
2156#define while_each_thread(g, t) \
2157	while ((t = next_thread(t)) != g)
2158
2159/* de_thread depends on thread_group_leader not being a pid based check */
2160#define thread_group_leader(p)	(p == p->group_leader)
2161
2162/* Do to the insanities of de_thread it is possible for a process
2163 * to have the pid of the thread group leader without actually being
2164 * the thread group leader.  For iteration through the pids in proc
2165 * all we care about is that we have a task with the appropriate
2166 * pid, we don't actually care if we have the right task.
2167 */
2168static inline int has_group_leader_pid(struct task_struct *p)
2169{
2170	return p->pid == p->tgid;
2171}
2172
2173static inline
2174int same_thread_group(struct task_struct *p1, struct task_struct *p2)
2175{
2176	return p1->tgid == p2->tgid;
2177}
2178
2179static inline struct task_struct *next_thread(const struct task_struct *p)
2180{
2181	return list_entry_rcu(p->thread_group.next,
2182			      struct task_struct, thread_group);
2183}
2184
2185static inline int thread_group_empty(struct task_struct *p)
2186{
2187	return list_empty(&p->thread_group);
2188}
2189
2190#define delay_group_leader(p) \
2191		(thread_group_leader(p) && !thread_group_empty(p))
2192
2193static inline int task_detached(struct task_struct *p)
2194{
2195	return p->exit_signal == -1;
2196}
2197
2198/*
2199 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2200 * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2201 * pins the final release of task.io_context.  Also protects ->cpuset and
2202 * ->cgroup.subsys[].
2203 *
2204 * Nests both inside and outside of read_lock(&tasklist_lock).
2205 * It must not be nested with write_lock_irq(&tasklist_lock),
2206 * neither inside nor outside.
2207 */
2208static inline void task_lock(struct task_struct *p)
2209{
2210	spin_lock(&p->alloc_lock);
2211}
2212
2213static inline void task_unlock(struct task_struct *p)
2214{
2215	spin_unlock(&p->alloc_lock);
2216}
2217
2218extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2219							unsigned long *flags);
2220
2221static inline void unlock_task_sighand(struct task_struct *tsk,
2222						unsigned long *flags)
2223{
2224	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2225}
2226
2227#ifndef __HAVE_THREAD_FUNCTIONS
2228
2229#define task_thread_info(task)	((struct thread_info *)(task)->stack)
2230#define task_stack_page(task)	((task)->stack)
2231
2232static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2233{
2234	*task_thread_info(p) = *task_thread_info(org);
2235	task_thread_info(p)->task = p;
2236}
2237
2238static inline unsigned long *end_of_stack(struct task_struct *p)
2239{
2240	return (unsigned long *)(task_thread_info(p) + 1);
2241}
2242
2243#endif
2244
2245static inline int object_is_on_stack(void *obj)
2246{
2247	void *stack = task_stack_page(current);
2248
2249	return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2250}
2251
2252extern void thread_info_cache_init(void);
2253
2254#ifdef CONFIG_DEBUG_STACK_USAGE
2255static inline unsigned long stack_not_used(struct task_struct *p)
2256{
2257	unsigned long *n = end_of_stack(p);
2258
2259	do { 	/* Skip over canary */
2260		n++;
2261	} while (!*n);
2262
2263	return (unsigned long)n - (unsigned long)end_of_stack(p);
2264}
2265#endif
2266
2267/* set thread flags in other task's structures
2268 * - see asm/thread_info.h for TIF_xxxx flags available
2269 */
2270static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2271{
2272	set_ti_thread_flag(task_thread_info(tsk), flag);
2273}
2274
2275static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2276{
2277	clear_ti_thread_flag(task_thread_info(tsk), flag);
2278}
2279
2280static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2281{
2282	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2283}
2284
2285static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2286{
2287	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2288}
2289
2290static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2291{
2292	return test_ti_thread_flag(task_thread_info(tsk), flag);
2293}
2294
2295static inline void set_tsk_need_resched(struct task_struct *tsk)
2296{
2297	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2298}
2299
2300static inline void clear_tsk_need_resched(struct task_struct *tsk)
2301{
2302	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2303}
2304
2305static inline int test_tsk_need_resched(struct task_struct *tsk)
2306{
2307	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2308}
2309
2310static inline int restart_syscall(void)
2311{
2312	set_tsk_thread_flag(current, TIF_SIGPENDING);
2313	return -ERESTARTNOINTR;
2314}
2315
2316static inline int signal_pending(struct task_struct *p)
2317{
2318	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2319}
2320
2321static inline int __fatal_signal_pending(struct task_struct *p)
2322{
2323	return unlikely(sigismember(&p->pending.signal, SIGKILL));
2324}
2325
2326static inline int fatal_signal_pending(struct task_struct *p)
2327{
2328	return signal_pending(p) && __fatal_signal_pending(p);
2329}
2330
2331static inline int signal_pending_state(long state, struct task_struct *p)
2332{
2333	if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2334		return 0;
2335	if (!signal_pending(p))
2336		return 0;
2337
2338	return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2339}
2340
2341static inline int need_resched(void)
2342{
2343	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
2344}
2345
2346/*
2347 * cond_resched() and cond_resched_lock(): latency reduction via
2348 * explicit rescheduling in places that are safe. The return
2349 * value indicates whether a reschedule was done in fact.
2350 * cond_resched_lock() will drop the spinlock before scheduling,
2351 * cond_resched_softirq() will enable bhs before scheduling.
2352 */
2353extern int _cond_resched(void);
2354
2355#define cond_resched() ({			\
2356	__might_sleep(__FILE__, __LINE__, 0);	\
2357	_cond_resched();			\
2358})
2359
2360extern int __cond_resched_lock(spinlock_t *lock);
2361
2362#ifdef CONFIG_PREEMPT
2363#define PREEMPT_LOCK_OFFSET	PREEMPT_OFFSET
2364#else
2365#define PREEMPT_LOCK_OFFSET	0
2366#endif
2367
2368#define cond_resched_lock(lock) ({				\
2369	__might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);	\
2370	__cond_resched_lock(lock);				\
2371})
2372
2373extern int __cond_resched_softirq(void);
2374
2375#define cond_resched_softirq() ({				\
2376	__might_sleep(__FILE__, __LINE__, SOFTIRQ_OFFSET);	\
2377	__cond_resched_softirq();				\
2378})
2379
2380/*
2381 * Does a critical section need to be broken due to another
2382 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2383 * but a general need for low latency)
2384 */
2385static inline int spin_needbreak(spinlock_t *lock)
2386{
2387#ifdef CONFIG_PREEMPT
2388	return spin_is_contended(lock);
2389#else
2390	return 0;
2391#endif
2392}
2393
2394/*
2395 * Thread group CPU time accounting.
2396 */
2397void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2398void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2399
2400static inline void thread_group_cputime_init(struct signal_struct *sig)
2401{
2402	spin_lock_init(&sig->cputimer.lock);
2403}
2404
2405static inline void thread_group_cputime_free(struct signal_struct *sig)
2406{
2407}
2408
2409/*
2410 * Reevaluate whether the task has signals pending delivery.
2411 * Wake the task if so.
2412 * This is required every time the blocked sigset_t changes.
2413 * callers must hold sighand->siglock.
2414 */
2415extern void recalc_sigpending_and_wake(struct task_struct *t);
2416extern void recalc_sigpending(void);
2417
2418extern void signal_wake_up(struct task_struct *t, int resume_stopped);
2419
2420/*
2421 * Wrappers for p->thread_info->cpu access. No-op on UP.
2422 */
2423#ifdef CONFIG_SMP
2424
2425static inline unsigned int task_cpu(const struct task_struct *p)
2426{
2427	return task_thread_info(p)->cpu;
2428}
2429
2430extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2431
2432#else
2433
2434static inline unsigned int task_cpu(const struct task_struct *p)
2435{
2436	return 0;
2437}
2438
2439static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2440{
2441}
2442
2443#endif /* CONFIG_SMP */
2444
2445#ifdef CONFIG_TRACING
2446extern void
2447__trace_special(void *__tr, void *__data,
2448		unsigned long arg1, unsigned long arg2, unsigned long arg3);
2449#else
2450static inline void
2451__trace_special(void *__tr, void *__data,
2452		unsigned long arg1, unsigned long arg2, unsigned long arg3)
2453{
2454}
2455#endif
2456
2457extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2458extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2459
2460extern void normalize_rt_tasks(void);
2461
2462#ifdef CONFIG_CGROUP_SCHED
2463
2464extern struct task_group init_task_group;
2465
2466extern struct task_group *sched_create_group(struct task_group *parent);
2467extern void sched_destroy_group(struct task_group *tg);
2468extern void sched_move_task(struct task_struct *tsk);
2469#ifdef CONFIG_FAIR_GROUP_SCHED
2470extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2471extern unsigned long sched_group_shares(struct task_group *tg);
2472#endif
2473#ifdef CONFIG_RT_GROUP_SCHED
2474extern int sched_group_set_rt_runtime(struct task_group *tg,
2475				      long rt_runtime_us);
2476extern long sched_group_rt_runtime(struct task_group *tg);
2477extern int sched_group_set_rt_period(struct task_group *tg,
2478				      long rt_period_us);
2479extern long sched_group_rt_period(struct task_group *tg);
2480extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
2481#endif
2482#endif
2483
2484extern int task_can_switch_user(struct user_struct *up,
2485					struct task_struct *tsk);
2486
2487#ifdef CONFIG_TASK_XACCT
2488static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2489{
2490	tsk->ioac.rchar += amt;
2491}
2492
2493static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2494{
2495	tsk->ioac.wchar += amt;
2496}
2497
2498static inline void inc_syscr(struct task_struct *tsk)
2499{
2500	tsk->ioac.syscr++;
2501}
2502
2503static inline void inc_syscw(struct task_struct *tsk)
2504{
2505	tsk->ioac.syscw++;
2506}
2507#else
2508static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2509{
2510}
2511
2512static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2513{
2514}
2515
2516static inline void inc_syscr(struct task_struct *tsk)
2517{
2518}
2519
2520static inline void inc_syscw(struct task_struct *tsk)
2521{
2522}
2523#endif
2524
2525#ifndef TASK_SIZE_OF
2526#define TASK_SIZE_OF(tsk)	TASK_SIZE
2527#endif
2528
2529/*
2530 * Call the function if the target task is executing on a CPU right now:
2531 */
2532extern void task_oncpu_function_call(struct task_struct *p,
2533				     void (*func) (void *info), void *info);
2534
2535
2536#ifdef CONFIG_MM_OWNER
2537extern void mm_update_next_owner(struct mm_struct *mm);
2538extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2539#else
2540static inline void mm_update_next_owner(struct mm_struct *mm)
2541{
2542}
2543
2544static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2545{
2546}
2547#endif /* CONFIG_MM_OWNER */
2548
2549static inline unsigned long task_rlimit(const struct task_struct *tsk,
2550		unsigned int limit)
2551{
2552	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur);
2553}
2554
2555static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
2556		unsigned int limit)
2557{
2558	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max);
2559}
2560
2561static inline unsigned long rlimit(unsigned int limit)
2562{
2563	return task_rlimit(current, limit);
2564}
2565
2566static inline unsigned long rlimit_max(unsigned int limit)
2567{
2568	return task_rlimit_max(current, limit);
2569}
2570
2571#endif /* __KERNEL__ */
2572
2573#endif
2574