xref: /linux-6.15/include/linux/sched.h (revision b898cc70)
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 
46 struct 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 
97 struct exec_domain;
98 struct futex_pi_state;
99 struct robust_list_head;
100 struct bio_list;
101 struct fs_struct;
102 struct perf_event_context;
103 
104 /*
105  * List of flags we want to share for kernel threads,
106  * if only because they are not used by them anyway.
107  */
108 #define CLONE_KERNEL	(CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
109 
110 /*
111  * These are the constant used to fake the fixed-point load-average
112  * counting. Some notes:
113  *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
114  *    a load-average precision of 10 bits integer + 11 bits fractional
115  *  - if you want to count load-averages more often, you need more
116  *    precision, or rounding will get you. With 2-second counting freq,
117  *    the EXP_n values would be 1981, 2034 and 2043 if still using only
118  *    11 bit fractions.
119  */
120 extern unsigned long avenrun[];		/* Load averages */
121 extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
122 
123 #define FSHIFT		11		/* nr of bits of precision */
124 #define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
125 #define LOAD_FREQ	(5*HZ+1)	/* 5 sec intervals */
126 #define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
127 #define EXP_5		2014		/* 1/exp(5sec/5min) */
128 #define EXP_15		2037		/* 1/exp(5sec/15min) */
129 
130 #define CALC_LOAD(load,exp,n) \
131 	load *= exp; \
132 	load += n*(FIXED_1-exp); \
133 	load >>= FSHIFT;
134 
135 extern unsigned long total_forks;
136 extern int nr_threads;
137 DECLARE_PER_CPU(unsigned long, process_counts);
138 extern int nr_processes(void);
139 extern unsigned long nr_running(void);
140 extern unsigned long nr_uninterruptible(void);
141 extern unsigned long nr_iowait(void);
142 extern unsigned long nr_iowait_cpu(int cpu);
143 extern unsigned long this_cpu_load(void);
144 
145 
146 extern void calc_global_load(void);
147 
148 extern unsigned long get_parent_ip(unsigned long addr);
149 
150 struct seq_file;
151 struct cfs_rq;
152 struct task_group;
153 #ifdef CONFIG_SCHED_DEBUG
154 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
155 extern void proc_sched_set_task(struct task_struct *p);
156 extern void
157 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
158 #else
159 static inline void
160 proc_sched_show_task(struct task_struct *p, struct seq_file *m)
161 {
162 }
163 static inline void proc_sched_set_task(struct task_struct *p)
164 {
165 }
166 static inline void
167 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
168 {
169 }
170 #endif
171 
172 /*
173  * Task state bitmask. NOTE! These bits are also
174  * encoded in fs/proc/array.c: get_task_state().
175  *
176  * We have two separate sets of flags: task->state
177  * is about runnability, while task->exit_state are
178  * about the task exiting. Confusing, but this way
179  * modifying one set can't modify the other one by
180  * mistake.
181  */
182 #define TASK_RUNNING		0
183 #define TASK_INTERRUPTIBLE	1
184 #define TASK_UNINTERRUPTIBLE	2
185 #define __TASK_STOPPED		4
186 #define __TASK_TRACED		8
187 /* in tsk->exit_state */
188 #define EXIT_ZOMBIE		16
189 #define EXIT_DEAD		32
190 /* in tsk->state again */
191 #define TASK_DEAD		64
192 #define TASK_WAKEKILL		128
193 #define TASK_WAKING		256
194 #define TASK_STATE_MAX		512
195 
196 #define TASK_STATE_TO_CHAR_STR "RSDTtZXxKW"
197 
198 extern char ___assert_task_state[1 - 2*!!(
199 		sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
200 
201 /* Convenience macros for the sake of set_task_state */
202 #define TASK_KILLABLE		(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
203 #define TASK_STOPPED		(TASK_WAKEKILL | __TASK_STOPPED)
204 #define TASK_TRACED		(TASK_WAKEKILL | __TASK_TRACED)
205 
206 /* Convenience macros for the sake of wake_up */
207 #define TASK_NORMAL		(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
208 #define TASK_ALL		(TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
209 
210 /* get_task_state() */
211 #define TASK_REPORT		(TASK_RUNNING | TASK_INTERRUPTIBLE | \
212 				 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
213 				 __TASK_TRACED)
214 
215 #define task_is_traced(task)	((task->state & __TASK_TRACED) != 0)
216 #define task_is_stopped(task)	((task->state & __TASK_STOPPED) != 0)
217 #define task_is_dead(task)	((task)->exit_state != 0)
218 #define task_is_stopped_or_traced(task)	\
219 			((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
220 #define task_contributes_to_load(task)	\
221 				((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
222 				 (task->flags & PF_FREEZING) == 0)
223 
224 #define __set_task_state(tsk, state_value)		\
225 	do { (tsk)->state = (state_value); } while (0)
226 #define set_task_state(tsk, state_value)		\
227 	set_mb((tsk)->state, (state_value))
228 
229 /*
230  * set_current_state() includes a barrier so that the write of current->state
231  * is correctly serialised wrt the caller's subsequent test of whether to
232  * actually sleep:
233  *
234  *	set_current_state(TASK_UNINTERRUPTIBLE);
235  *	if (do_i_need_to_sleep())
236  *		schedule();
237  *
238  * If the caller does not need such serialisation then use __set_current_state()
239  */
240 #define __set_current_state(state_value)			\
241 	do { current->state = (state_value); } while (0)
242 #define set_current_state(state_value)		\
243 	set_mb(current->state, (state_value))
244 
245 /* Task command name length */
246 #define TASK_COMM_LEN 16
247 
248 #include <linux/spinlock.h>
249 
250 /*
251  * This serializes "schedule()" and also protects
252  * the run-queue from deletions/modifications (but
253  * _adding_ to the beginning of the run-queue has
254  * a separate lock).
255  */
256 extern rwlock_t tasklist_lock;
257 extern spinlock_t mmlist_lock;
258 
259 struct task_struct;
260 
261 #ifdef CONFIG_PROVE_RCU
262 extern int lockdep_tasklist_lock_is_held(void);
263 #endif /* #ifdef CONFIG_PROVE_RCU */
264 
265 extern void sched_init(void);
266 extern void sched_init_smp(void);
267 extern asmlinkage void schedule_tail(struct task_struct *prev);
268 extern void init_idle(struct task_struct *idle, int cpu);
269 extern void init_idle_bootup_task(struct task_struct *idle);
270 
271 extern int runqueue_is_locked(int cpu);
272 
273 extern cpumask_var_t nohz_cpu_mask;
274 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
275 extern void select_nohz_load_balancer(int stop_tick);
276 extern int get_nohz_timer_target(void);
277 #else
278 static inline void select_nohz_load_balancer(int stop_tick) { }
279 #endif
280 
281 /*
282  * Only dump TASK_* tasks. (0 for all tasks)
283  */
284 extern void show_state_filter(unsigned long state_filter);
285 
286 static inline void show_state(void)
287 {
288 	show_state_filter(0);
289 }
290 
291 extern 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  */
298 extern void show_stack(struct task_struct *task, unsigned long *sp);
299 
300 void io_schedule(void);
301 long io_schedule_timeout(long timeout);
302 
303 extern void cpu_init (void);
304 extern void trap_init(void);
305 extern void update_process_times(int user);
306 extern void scheduler_tick(void);
307 
308 extern void sched_show_task(struct task_struct *p);
309 
310 #ifdef CONFIG_LOCKUP_DETECTOR
311 extern void touch_softlockup_watchdog(void);
312 extern void touch_softlockup_watchdog_sync(void);
313 extern void touch_all_softlockup_watchdogs(void);
314 extern int proc_dowatchdog_thresh(struct ctl_table *table, int write,
315 				  void __user *buffer,
316 				  size_t *lenp, loff_t *ppos);
317 extern unsigned int  softlockup_panic;
318 extern int softlockup_thresh;
319 #else
320 static inline void touch_softlockup_watchdog(void)
321 {
322 }
323 static inline void touch_softlockup_watchdog_sync(void)
324 {
325 }
326 static inline void touch_all_softlockup_watchdogs(void)
327 {
328 }
329 #endif
330 
331 #ifdef CONFIG_DETECT_HUNG_TASK
332 extern unsigned int  sysctl_hung_task_panic;
333 extern unsigned long sysctl_hung_task_check_count;
334 extern unsigned long sysctl_hung_task_timeout_secs;
335 extern unsigned long sysctl_hung_task_warnings;
336 extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
337 					 void __user *buffer,
338 					 size_t *lenp, loff_t *ppos);
339 #endif
340 
341 /* Attach to any functions which should be ignored in wchan output. */
342 #define __sched		__attribute__((__section__(".sched.text")))
343 
344 /* Linker adds these: start and end of __sched functions */
345 extern char __sched_text_start[], __sched_text_end[];
346 
347 /* Is this address in the __sched functions? */
348 extern int in_sched_functions(unsigned long addr);
349 
350 #define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
351 extern signed long schedule_timeout(signed long timeout);
352 extern signed long schedule_timeout_interruptible(signed long timeout);
353 extern signed long schedule_timeout_killable(signed long timeout);
354 extern signed long schedule_timeout_uninterruptible(signed long timeout);
355 asmlinkage void schedule(void);
356 extern int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner);
357 
358 struct nsproxy;
359 struct user_namespace;
360 
361 /*
362  * Default maximum number of active map areas, this limits the number of vmas
363  * per mm struct. Users can overwrite this number by sysctl but there is a
364  * problem.
365  *
366  * When a program's coredump is generated as ELF format, a section is created
367  * per a vma. In ELF, the number of sections is represented in unsigned short.
368  * This means the number of sections should be smaller than 65535 at coredump.
369  * Because the kernel adds some informative sections to a image of program at
370  * generating coredump, we need some margin. The number of extra sections is
371  * 1-3 now and depends on arch. We use "5" as safe margin, here.
372  */
373 #define MAPCOUNT_ELF_CORE_MARGIN	(5)
374 #define DEFAULT_MAX_MAP_COUNT	(USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
375 
376 extern int sysctl_max_map_count;
377 
378 #include <linux/aio.h>
379 
380 #ifdef CONFIG_MMU
381 extern void arch_pick_mmap_layout(struct mm_struct *mm);
382 extern unsigned long
383 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
384 		       unsigned long, unsigned long);
385 extern unsigned long
386 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
387 			  unsigned long len, unsigned long pgoff,
388 			  unsigned long flags);
389 extern void arch_unmap_area(struct mm_struct *, unsigned long);
390 extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
391 #else
392 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
393 #endif
394 
395 
396 extern void set_dumpable(struct mm_struct *mm, int value);
397 extern int get_dumpable(struct mm_struct *mm);
398 
399 /* mm flags */
400 /* dumpable bits */
401 #define MMF_DUMPABLE      0  /* core dump is permitted */
402 #define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
403 
404 #define MMF_DUMPABLE_BITS 2
405 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
406 
407 /* coredump filter bits */
408 #define MMF_DUMP_ANON_PRIVATE	2
409 #define MMF_DUMP_ANON_SHARED	3
410 #define MMF_DUMP_MAPPED_PRIVATE	4
411 #define MMF_DUMP_MAPPED_SHARED	5
412 #define MMF_DUMP_ELF_HEADERS	6
413 #define MMF_DUMP_HUGETLB_PRIVATE 7
414 #define MMF_DUMP_HUGETLB_SHARED  8
415 
416 #define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
417 #define MMF_DUMP_FILTER_BITS	7
418 #define MMF_DUMP_FILTER_MASK \
419 	(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
420 #define MMF_DUMP_FILTER_DEFAULT \
421 	((1 << MMF_DUMP_ANON_PRIVATE) |	(1 << MMF_DUMP_ANON_SHARED) |\
422 	 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
423 
424 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
425 # define MMF_DUMP_MASK_DEFAULT_ELF	(1 << MMF_DUMP_ELF_HEADERS)
426 #else
427 # define MMF_DUMP_MASK_DEFAULT_ELF	0
428 #endif
429 					/* leave room for more dump flags */
430 #define MMF_VM_MERGEABLE	16	/* KSM may merge identical pages */
431 
432 #define MMF_INIT_MASK		(MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
433 
434 struct sighand_struct {
435 	atomic_t		count;
436 	struct k_sigaction	action[_NSIG];
437 	spinlock_t		siglock;
438 	wait_queue_head_t	signalfd_wqh;
439 };
440 
441 struct pacct_struct {
442 	int			ac_flag;
443 	long			ac_exitcode;
444 	unsigned long		ac_mem;
445 	cputime_t		ac_utime, ac_stime;
446 	unsigned long		ac_minflt, ac_majflt;
447 };
448 
449 struct cpu_itimer {
450 	cputime_t expires;
451 	cputime_t incr;
452 	u32 error;
453 	u32 incr_error;
454 };
455 
456 /**
457  * struct task_cputime - collected CPU time counts
458  * @utime:		time spent in user mode, in &cputime_t units
459  * @stime:		time spent in kernel mode, in &cputime_t units
460  * @sum_exec_runtime:	total time spent on the CPU, in nanoseconds
461  *
462  * This structure groups together three kinds of CPU time that are
463  * tracked for threads and thread groups.  Most things considering
464  * CPU time want to group these counts together and treat all three
465  * of them in parallel.
466  */
467 struct task_cputime {
468 	cputime_t utime;
469 	cputime_t stime;
470 	unsigned long long sum_exec_runtime;
471 };
472 /* Alternate field names when used to cache expirations. */
473 #define prof_exp	stime
474 #define virt_exp	utime
475 #define sched_exp	sum_exec_runtime
476 
477 #define INIT_CPUTIME	\
478 	(struct task_cputime) {					\
479 		.utime = cputime_zero,				\
480 		.stime = cputime_zero,				\
481 		.sum_exec_runtime = 0,				\
482 	}
483 
484 /*
485  * Disable preemption until the scheduler is running.
486  * Reset by start_kernel()->sched_init()->init_idle().
487  *
488  * We include PREEMPT_ACTIVE to avoid cond_resched() from working
489  * before the scheduler is active -- see should_resched().
490  */
491 #define INIT_PREEMPT_COUNT	(1 + PREEMPT_ACTIVE)
492 
493 /**
494  * struct thread_group_cputimer - thread group interval timer counts
495  * @cputime:		thread group interval timers.
496  * @running:		non-zero when there are timers running and
497  * 			@cputime receives updates.
498  * @lock:		lock for fields in this struct.
499  *
500  * This structure contains the version of task_cputime, above, that is
501  * used for thread group CPU timer calculations.
502  */
503 struct thread_group_cputimer {
504 	struct task_cputime cputime;
505 	int running;
506 	spinlock_t lock;
507 };
508 
509 /*
510  * NOTE! "signal_struct" does not have it's own
511  * locking, because a shared signal_struct always
512  * implies a shared sighand_struct, so locking
513  * sighand_struct is always a proper superset of
514  * the locking of signal_struct.
515  */
516 struct signal_struct {
517 	atomic_t		sigcnt;
518 	atomic_t		live;
519 	int			nr_threads;
520 
521 	wait_queue_head_t	wait_chldexit;	/* for wait4() */
522 
523 	/* current thread group signal load-balancing target: */
524 	struct task_struct	*curr_target;
525 
526 	/* shared signal handling: */
527 	struct sigpending	shared_pending;
528 
529 	/* thread group exit support */
530 	int			group_exit_code;
531 	/* overloaded:
532 	 * - notify group_exit_task when ->count is equal to notify_count
533 	 * - everyone except group_exit_task is stopped during signal delivery
534 	 *   of fatal signals, group_exit_task processes the signal.
535 	 */
536 	int			notify_count;
537 	struct task_struct	*group_exit_task;
538 
539 	/* thread group stop support, overloads group_exit_code too */
540 	int			group_stop_count;
541 	unsigned int		flags; /* see SIGNAL_* flags below */
542 
543 	/* POSIX.1b Interval Timers */
544 	struct list_head posix_timers;
545 
546 	/* ITIMER_REAL timer for the process */
547 	struct hrtimer real_timer;
548 	struct pid *leader_pid;
549 	ktime_t it_real_incr;
550 
551 	/*
552 	 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
553 	 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
554 	 * values are defined to 0 and 1 respectively
555 	 */
556 	struct cpu_itimer it[2];
557 
558 	/*
559 	 * Thread group totals for process CPU timers.
560 	 * See thread_group_cputimer(), et al, for details.
561 	 */
562 	struct thread_group_cputimer cputimer;
563 
564 	/* Earliest-expiration cache. */
565 	struct task_cputime cputime_expires;
566 
567 	struct list_head cpu_timers[3];
568 
569 	struct pid *tty_old_pgrp;
570 
571 	/* boolean value for session group leader */
572 	int leader;
573 
574 	struct tty_struct *tty; /* NULL if no tty */
575 
576 	/*
577 	 * Cumulative resource counters for dead threads in the group,
578 	 * and for reaped dead child processes forked by this group.
579 	 * Live threads maintain their own counters and add to these
580 	 * in __exit_signal, except for the group leader.
581 	 */
582 	cputime_t utime, stime, cutime, cstime;
583 	cputime_t gtime;
584 	cputime_t cgtime;
585 #ifndef CONFIG_VIRT_CPU_ACCOUNTING
586 	cputime_t prev_utime, prev_stime;
587 #endif
588 	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
589 	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
590 	unsigned long inblock, oublock, cinblock, coublock;
591 	unsigned long maxrss, cmaxrss;
592 	struct task_io_accounting ioac;
593 
594 	/*
595 	 * Cumulative ns of schedule CPU time fo dead threads in the
596 	 * group, not including a zombie group leader, (This only differs
597 	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
598 	 * other than jiffies.)
599 	 */
600 	unsigned long long sum_sched_runtime;
601 
602 	/*
603 	 * We don't bother to synchronize most readers of this at all,
604 	 * because there is no reader checking a limit that actually needs
605 	 * to get both rlim_cur and rlim_max atomically, and either one
606 	 * alone is a single word that can safely be read normally.
607 	 * getrlimit/setrlimit use task_lock(current->group_leader) to
608 	 * protect this instead of the siglock, because they really
609 	 * have no need to disable irqs.
610 	 */
611 	struct rlimit rlim[RLIM_NLIMITS];
612 
613 #ifdef CONFIG_BSD_PROCESS_ACCT
614 	struct pacct_struct pacct;	/* per-process accounting information */
615 #endif
616 #ifdef CONFIG_TASKSTATS
617 	struct taskstats *stats;
618 #endif
619 #ifdef CONFIG_AUDIT
620 	unsigned audit_tty;
621 	struct tty_audit_buf *tty_audit_buf;
622 #endif
623 
624 	int oom_adj;	/* OOM kill score adjustment (bit shift) */
625 };
626 
627 /* Context switch must be unlocked if interrupts are to be enabled */
628 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
629 # define __ARCH_WANT_UNLOCKED_CTXSW
630 #endif
631 
632 /*
633  * Bits in flags field of signal_struct.
634  */
635 #define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
636 #define SIGNAL_STOP_DEQUEUED	0x00000002 /* stop signal dequeued */
637 #define SIGNAL_STOP_CONTINUED	0x00000004 /* SIGCONT since WCONTINUED reap */
638 #define SIGNAL_GROUP_EXIT	0x00000008 /* group exit in progress */
639 /*
640  * Pending notifications to parent.
641  */
642 #define SIGNAL_CLD_STOPPED	0x00000010
643 #define SIGNAL_CLD_CONTINUED	0x00000020
644 #define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
645 
646 #define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */
647 
648 /* If true, all threads except ->group_exit_task have pending SIGKILL */
649 static inline int signal_group_exit(const struct signal_struct *sig)
650 {
651 	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
652 		(sig->group_exit_task != NULL);
653 }
654 
655 /*
656  * Some day this will be a full-fledged user tracking system..
657  */
658 struct user_struct {
659 	atomic_t __count;	/* reference count */
660 	atomic_t processes;	/* How many processes does this user have? */
661 	atomic_t files;		/* How many open files does this user have? */
662 	atomic_t sigpending;	/* How many pending signals does this user have? */
663 #ifdef CONFIG_INOTIFY_USER
664 	atomic_t inotify_watches; /* How many inotify watches does this user have? */
665 	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
666 #endif
667 #ifdef CONFIG_EPOLL
668 	atomic_t epoll_watches;	/* The number of file descriptors currently watched */
669 #endif
670 #ifdef CONFIG_POSIX_MQUEUE
671 	/* protected by mq_lock	*/
672 	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
673 #endif
674 	unsigned long locked_shm; /* How many pages of mlocked shm ? */
675 
676 #ifdef CONFIG_KEYS
677 	struct key *uid_keyring;	/* UID specific keyring */
678 	struct key *session_keyring;	/* UID's default session keyring */
679 #endif
680 
681 	/* Hash table maintenance information */
682 	struct hlist_node uidhash_node;
683 	uid_t uid;
684 	struct user_namespace *user_ns;
685 
686 #ifdef CONFIG_PERF_EVENTS
687 	atomic_long_t locked_vm;
688 #endif
689 };
690 
691 extern int uids_sysfs_init(void);
692 
693 extern struct user_struct *find_user(uid_t);
694 
695 extern struct user_struct root_user;
696 #define INIT_USER (&root_user)
697 
698 
699 struct backing_dev_info;
700 struct reclaim_state;
701 
702 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
703 struct sched_info {
704 	/* cumulative counters */
705 	unsigned long pcount;	      /* # of times run on this cpu */
706 	unsigned long long run_delay; /* time spent waiting on a runqueue */
707 
708 	/* timestamps */
709 	unsigned long long last_arrival,/* when we last ran on a cpu */
710 			   last_queued;	/* when we were last queued to run */
711 #ifdef CONFIG_SCHEDSTATS
712 	/* BKL stats */
713 	unsigned int bkl_count;
714 #endif
715 };
716 #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
717 
718 #ifdef CONFIG_TASK_DELAY_ACCT
719 struct task_delay_info {
720 	spinlock_t	lock;
721 	unsigned int	flags;	/* Private per-task flags */
722 
723 	/* For each stat XXX, add following, aligned appropriately
724 	 *
725 	 * struct timespec XXX_start, XXX_end;
726 	 * u64 XXX_delay;
727 	 * u32 XXX_count;
728 	 *
729 	 * Atomicity of updates to XXX_delay, XXX_count protected by
730 	 * single lock above (split into XXX_lock if contention is an issue).
731 	 */
732 
733 	/*
734 	 * XXX_count is incremented on every XXX operation, the delay
735 	 * associated with the operation is added to XXX_delay.
736 	 * XXX_delay contains the accumulated delay time in nanoseconds.
737 	 */
738 	struct timespec blkio_start, blkio_end;	/* Shared by blkio, swapin */
739 	u64 blkio_delay;	/* wait for sync block io completion */
740 	u64 swapin_delay;	/* wait for swapin block io completion */
741 	u32 blkio_count;	/* total count of the number of sync block */
742 				/* io operations performed */
743 	u32 swapin_count;	/* total count of the number of swapin block */
744 				/* io operations performed */
745 
746 	struct timespec freepages_start, freepages_end;
747 	u64 freepages_delay;	/* wait for memory reclaim */
748 	u32 freepages_count;	/* total count of memory reclaim */
749 };
750 #endif	/* CONFIG_TASK_DELAY_ACCT */
751 
752 static inline int sched_info_on(void)
753 {
754 #ifdef CONFIG_SCHEDSTATS
755 	return 1;
756 #elif defined(CONFIG_TASK_DELAY_ACCT)
757 	extern int delayacct_on;
758 	return delayacct_on;
759 #else
760 	return 0;
761 #endif
762 }
763 
764 enum cpu_idle_type {
765 	CPU_IDLE,
766 	CPU_NOT_IDLE,
767 	CPU_NEWLY_IDLE,
768 	CPU_MAX_IDLE_TYPES
769 };
770 
771 /*
772  * sched-domains (multiprocessor balancing) declarations:
773  */
774 
775 /*
776  * Increase resolution of nice-level calculations:
777  */
778 #define SCHED_LOAD_SHIFT	10
779 #define SCHED_LOAD_SCALE	(1L << SCHED_LOAD_SHIFT)
780 
781 #define SCHED_LOAD_SCALE_FUZZ	SCHED_LOAD_SCALE
782 
783 #ifdef CONFIG_SMP
784 #define SD_LOAD_BALANCE		0x0001	/* Do load balancing on this domain. */
785 #define SD_BALANCE_NEWIDLE	0x0002	/* Balance when about to become idle */
786 #define SD_BALANCE_EXEC		0x0004	/* Balance on exec */
787 #define SD_BALANCE_FORK		0x0008	/* Balance on fork, clone */
788 #define SD_BALANCE_WAKE		0x0010  /* Balance on wakeup */
789 #define SD_WAKE_AFFINE		0x0020	/* Wake task to waking CPU */
790 #define SD_PREFER_LOCAL		0x0040  /* Prefer to keep tasks local to this domain */
791 #define SD_SHARE_CPUPOWER	0x0080	/* Domain members share cpu power */
792 #define SD_POWERSAVINGS_BALANCE	0x0100	/* Balance for power savings */
793 #define SD_SHARE_PKG_RESOURCES	0x0200	/* Domain members share cpu pkg resources */
794 #define SD_SERIALIZE		0x0400	/* Only a single load balancing instance */
795 #define SD_ASYM_PACKING		0x0800  /* Place busy groups earlier in the domain */
796 #define SD_PREFER_SIBLING	0x1000	/* Prefer to place tasks in a sibling domain */
797 
798 enum powersavings_balance_level {
799 	POWERSAVINGS_BALANCE_NONE = 0,  /* No power saving load balance */
800 	POWERSAVINGS_BALANCE_BASIC,	/* Fill one thread/core/package
801 					 * first for long running threads
802 					 */
803 	POWERSAVINGS_BALANCE_WAKEUP,	/* Also bias task wakeups to semi-idle
804 					 * cpu package for power savings
805 					 */
806 	MAX_POWERSAVINGS_BALANCE_LEVELS
807 };
808 
809 extern int sched_mc_power_savings, sched_smt_power_savings;
810 
811 static inline int sd_balance_for_mc_power(void)
812 {
813 	if (sched_smt_power_savings)
814 		return SD_POWERSAVINGS_BALANCE;
815 
816 	if (!sched_mc_power_savings)
817 		return SD_PREFER_SIBLING;
818 
819 	return 0;
820 }
821 
822 static inline int sd_balance_for_package_power(void)
823 {
824 	if (sched_mc_power_savings | sched_smt_power_savings)
825 		return SD_POWERSAVINGS_BALANCE;
826 
827 	return SD_PREFER_SIBLING;
828 }
829 
830 extern int __weak arch_sd_sibiling_asym_packing(void);
831 
832 /*
833  * Optimise SD flags for power savings:
834  * SD_BALANCE_NEWIDLE helps agressive task consolidation and power savings.
835  * Keep default SD flags if sched_{smt,mc}_power_saving=0
836  */
837 
838 static inline int sd_power_saving_flags(void)
839 {
840 	if (sched_mc_power_savings | sched_smt_power_savings)
841 		return SD_BALANCE_NEWIDLE;
842 
843 	return 0;
844 }
845 
846 struct sched_group {
847 	struct sched_group *next;	/* Must be a circular list */
848 
849 	/*
850 	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
851 	 * single CPU.
852 	 */
853 	unsigned int cpu_power, cpu_power_orig;
854 
855 	/*
856 	 * The CPUs this group covers.
857 	 *
858 	 * NOTE: this field is variable length. (Allocated dynamically
859 	 * by attaching extra space to the end of the structure,
860 	 * depending on how many CPUs the kernel has booted up with)
861 	 *
862 	 * It is also be embedded into static data structures at build
863 	 * time. (See 'struct static_sched_group' in kernel/sched.c)
864 	 */
865 	unsigned long cpumask[0];
866 };
867 
868 static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
869 {
870 	return to_cpumask(sg->cpumask);
871 }
872 
873 enum sched_domain_level {
874 	SD_LV_NONE = 0,
875 	SD_LV_SIBLING,
876 	SD_LV_MC,
877 	SD_LV_CPU,
878 	SD_LV_NODE,
879 	SD_LV_ALLNODES,
880 	SD_LV_MAX
881 };
882 
883 struct sched_domain_attr {
884 	int relax_domain_level;
885 };
886 
887 #define SD_ATTR_INIT	(struct sched_domain_attr) {	\
888 	.relax_domain_level = -1,			\
889 }
890 
891 struct sched_domain {
892 	/* These fields must be setup */
893 	struct sched_domain *parent;	/* top domain must be null terminated */
894 	struct sched_domain *child;	/* bottom domain must be null terminated */
895 	struct sched_group *groups;	/* the balancing groups of the domain */
896 	unsigned long min_interval;	/* Minimum balance interval ms */
897 	unsigned long max_interval;	/* Maximum balance interval ms */
898 	unsigned int busy_factor;	/* less balancing by factor if busy */
899 	unsigned int imbalance_pct;	/* No balance until over watermark */
900 	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
901 	unsigned int busy_idx;
902 	unsigned int idle_idx;
903 	unsigned int newidle_idx;
904 	unsigned int wake_idx;
905 	unsigned int forkexec_idx;
906 	unsigned int smt_gain;
907 	int flags;			/* See SD_* */
908 	enum sched_domain_level level;
909 
910 	/* Runtime fields. */
911 	unsigned long last_balance;	/* init to jiffies. units in jiffies */
912 	unsigned int balance_interval;	/* initialise to 1. units in ms. */
913 	unsigned int nr_balance_failed; /* initialise to 0 */
914 
915 	u64 last_update;
916 
917 #ifdef CONFIG_SCHEDSTATS
918 	/* load_balance() stats */
919 	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
920 	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
921 	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
922 	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
923 	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
924 	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
925 	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
926 	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
927 
928 	/* Active load balancing */
929 	unsigned int alb_count;
930 	unsigned int alb_failed;
931 	unsigned int alb_pushed;
932 
933 	/* SD_BALANCE_EXEC stats */
934 	unsigned int sbe_count;
935 	unsigned int sbe_balanced;
936 	unsigned int sbe_pushed;
937 
938 	/* SD_BALANCE_FORK stats */
939 	unsigned int sbf_count;
940 	unsigned int sbf_balanced;
941 	unsigned int sbf_pushed;
942 
943 	/* try_to_wake_up() stats */
944 	unsigned int ttwu_wake_remote;
945 	unsigned int ttwu_move_affine;
946 	unsigned int ttwu_move_balance;
947 #endif
948 #ifdef CONFIG_SCHED_DEBUG
949 	char *name;
950 #endif
951 
952 	unsigned int span_weight;
953 	/*
954 	 * Span of all CPUs in this domain.
955 	 *
956 	 * NOTE: this field is variable length. (Allocated dynamically
957 	 * by attaching extra space to the end of the structure,
958 	 * depending on how many CPUs the kernel has booted up with)
959 	 *
960 	 * It is also be embedded into static data structures at build
961 	 * time. (See 'struct static_sched_domain' in kernel/sched.c)
962 	 */
963 	unsigned long span[0];
964 };
965 
966 static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
967 {
968 	return to_cpumask(sd->span);
969 }
970 
971 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
972 				    struct sched_domain_attr *dattr_new);
973 
974 /* Allocate an array of sched domains, for partition_sched_domains(). */
975 cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
976 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
977 
978 /* Test a flag in parent sched domain */
979 static inline int test_sd_parent(struct sched_domain *sd, int flag)
980 {
981 	if (sd->parent && (sd->parent->flags & flag))
982 		return 1;
983 
984 	return 0;
985 }
986 
987 unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu);
988 unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu);
989 
990 #else /* CONFIG_SMP */
991 
992 struct sched_domain_attr;
993 
994 static inline void
995 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
996 			struct sched_domain_attr *dattr_new)
997 {
998 }
999 #endif	/* !CONFIG_SMP */
1000 
1001 
1002 struct io_context;			/* See blkdev.h */
1003 
1004 
1005 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1006 extern void prefetch_stack(struct task_struct *t);
1007 #else
1008 static inline void prefetch_stack(struct task_struct *t) { }
1009 #endif
1010 
1011 struct audit_context;		/* See audit.c */
1012 struct mempolicy;
1013 struct pipe_inode_info;
1014 struct uts_namespace;
1015 
1016 struct rq;
1017 struct sched_domain;
1018 
1019 /*
1020  * wake flags
1021  */
1022 #define WF_SYNC		0x01		/* waker goes to sleep after wakup */
1023 #define WF_FORK		0x02		/* child wakeup after fork */
1024 
1025 #define ENQUEUE_WAKEUP		1
1026 #define ENQUEUE_WAKING		2
1027 #define ENQUEUE_HEAD		4
1028 
1029 #define DEQUEUE_SLEEP		1
1030 
1031 struct sched_class {
1032 	const struct sched_class *next;
1033 
1034 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1035 	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1036 	void (*yield_task) (struct rq *rq);
1037 
1038 	void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
1039 
1040 	struct task_struct * (*pick_next_task) (struct rq *rq);
1041 	void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1042 
1043 #ifdef CONFIG_SMP
1044 	int  (*select_task_rq)(struct rq *rq, struct task_struct *p,
1045 			       int sd_flag, int flags);
1046 
1047 	void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
1048 	void (*post_schedule) (struct rq *this_rq);
1049 	void (*task_waking) (struct rq *this_rq, struct task_struct *task);
1050 	void (*task_woken) (struct rq *this_rq, struct task_struct *task);
1051 
1052 	void (*set_cpus_allowed)(struct task_struct *p,
1053 				 const struct cpumask *newmask);
1054 
1055 	void (*rq_online)(struct rq *rq);
1056 	void (*rq_offline)(struct rq *rq);
1057 #endif
1058 
1059 	void (*set_curr_task) (struct rq *rq);
1060 	void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1061 	void (*task_fork) (struct task_struct *p);
1062 
1063 	void (*switched_from) (struct rq *this_rq, struct task_struct *task,
1064 			       int running);
1065 	void (*switched_to) (struct rq *this_rq, struct task_struct *task,
1066 			     int running);
1067 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1068 			     int oldprio, int running);
1069 
1070 	unsigned int (*get_rr_interval) (struct rq *rq,
1071 					 struct task_struct *task);
1072 
1073 #ifdef CONFIG_FAIR_GROUP_SCHED
1074 	void (*moved_group) (struct task_struct *p, int on_rq);
1075 #endif
1076 };
1077 
1078 struct load_weight {
1079 	unsigned long weight, inv_weight;
1080 };
1081 
1082 #ifdef CONFIG_SCHEDSTATS
1083 struct sched_statistics {
1084 	u64			wait_start;
1085 	u64			wait_max;
1086 	u64			wait_count;
1087 	u64			wait_sum;
1088 	u64			iowait_count;
1089 	u64			iowait_sum;
1090 
1091 	u64			sleep_start;
1092 	u64			sleep_max;
1093 	s64			sum_sleep_runtime;
1094 
1095 	u64			block_start;
1096 	u64			block_max;
1097 	u64			exec_max;
1098 	u64			slice_max;
1099 
1100 	u64			nr_migrations_cold;
1101 	u64			nr_failed_migrations_affine;
1102 	u64			nr_failed_migrations_running;
1103 	u64			nr_failed_migrations_hot;
1104 	u64			nr_forced_migrations;
1105 
1106 	u64			nr_wakeups;
1107 	u64			nr_wakeups_sync;
1108 	u64			nr_wakeups_migrate;
1109 	u64			nr_wakeups_local;
1110 	u64			nr_wakeups_remote;
1111 	u64			nr_wakeups_affine;
1112 	u64			nr_wakeups_affine_attempts;
1113 	u64			nr_wakeups_passive;
1114 	u64			nr_wakeups_idle;
1115 };
1116 #endif
1117 
1118 struct sched_entity {
1119 	struct load_weight	load;		/* for load-balancing */
1120 	struct rb_node		run_node;
1121 	struct list_head	group_node;
1122 	unsigned int		on_rq;
1123 
1124 	u64			exec_start;
1125 	u64			sum_exec_runtime;
1126 	u64			vruntime;
1127 	u64			prev_sum_exec_runtime;
1128 
1129 	u64			nr_migrations;
1130 
1131 #ifdef CONFIG_SCHEDSTATS
1132 	struct sched_statistics statistics;
1133 #endif
1134 
1135 #ifdef CONFIG_FAIR_GROUP_SCHED
1136 	struct sched_entity	*parent;
1137 	/* rq on which this entity is (to be) queued: */
1138 	struct cfs_rq		*cfs_rq;
1139 	/* rq "owned" by this entity/group: */
1140 	struct cfs_rq		*my_q;
1141 #endif
1142 };
1143 
1144 struct sched_rt_entity {
1145 	struct list_head run_list;
1146 	unsigned long timeout;
1147 	unsigned int time_slice;
1148 	int nr_cpus_allowed;
1149 
1150 	struct sched_rt_entity *back;
1151 #ifdef CONFIG_RT_GROUP_SCHED
1152 	struct sched_rt_entity	*parent;
1153 	/* rq on which this entity is (to be) queued: */
1154 	struct rt_rq		*rt_rq;
1155 	/* rq "owned" by this entity/group: */
1156 	struct rt_rq		*my_q;
1157 #endif
1158 };
1159 
1160 struct rcu_node;
1161 
1162 struct task_struct {
1163 	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
1164 	void *stack;
1165 	atomic_t usage;
1166 	unsigned int flags;	/* per process flags, defined below */
1167 	unsigned int ptrace;
1168 
1169 	int lock_depth;		/* BKL lock depth */
1170 
1171 #ifdef CONFIG_SMP
1172 #ifdef __ARCH_WANT_UNLOCKED_CTXSW
1173 	int oncpu;
1174 #endif
1175 #endif
1176 
1177 	int prio, static_prio, normal_prio;
1178 	unsigned int rt_priority;
1179 	const struct sched_class *sched_class;
1180 	struct sched_entity se;
1181 	struct sched_rt_entity rt;
1182 
1183 #ifdef CONFIG_PREEMPT_NOTIFIERS
1184 	/* list of struct preempt_notifier: */
1185 	struct hlist_head preempt_notifiers;
1186 #endif
1187 
1188 	/*
1189 	 * fpu_counter contains the number of consecutive context switches
1190 	 * that the FPU is used. If this is over a threshold, the lazy fpu
1191 	 * saving becomes unlazy to save the trap. This is an unsigned char
1192 	 * so that after 256 times the counter wraps and the behavior turns
1193 	 * lazy again; this to deal with bursty apps that only use FPU for
1194 	 * a short time
1195 	 */
1196 	unsigned char fpu_counter;
1197 #ifdef CONFIG_BLK_DEV_IO_TRACE
1198 	unsigned int btrace_seq;
1199 #endif
1200 
1201 	unsigned int policy;
1202 	cpumask_t cpus_allowed;
1203 
1204 #ifdef CONFIG_TREE_PREEMPT_RCU
1205 	int rcu_read_lock_nesting;
1206 	char rcu_read_unlock_special;
1207 	struct rcu_node *rcu_blocked_node;
1208 	struct list_head rcu_node_entry;
1209 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1210 
1211 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1212 	struct sched_info sched_info;
1213 #endif
1214 
1215 	struct list_head tasks;
1216 	struct plist_node pushable_tasks;
1217 
1218 	struct mm_struct *mm, *active_mm;
1219 #if defined(SPLIT_RSS_COUNTING)
1220 	struct task_rss_stat	rss_stat;
1221 #endif
1222 /* task state */
1223 	int exit_state;
1224 	int exit_code, exit_signal;
1225 	int pdeath_signal;  /*  The signal sent when the parent dies  */
1226 	/* ??? */
1227 	unsigned int personality;
1228 	unsigned did_exec:1;
1229 	unsigned in_execve:1;	/* Tell the LSMs that the process is doing an
1230 				 * execve */
1231 	unsigned in_iowait:1;
1232 
1233 
1234 	/* Revert to default priority/policy when forking */
1235 	unsigned sched_reset_on_fork:1;
1236 
1237 	pid_t pid;
1238 	pid_t tgid;
1239 
1240 #ifdef CONFIG_CC_STACKPROTECTOR
1241 	/* Canary value for the -fstack-protector gcc feature */
1242 	unsigned long stack_canary;
1243 #endif
1244 
1245 	/*
1246 	 * pointers to (original) parent process, youngest child, younger sibling,
1247 	 * older sibling, respectively.  (p->father can be replaced with
1248 	 * p->real_parent->pid)
1249 	 */
1250 	struct task_struct *real_parent; /* real parent process */
1251 	struct task_struct *parent; /* recipient of SIGCHLD, wait4() reports */
1252 	/*
1253 	 * children/sibling forms the list of my natural children
1254 	 */
1255 	struct list_head children;	/* list of my children */
1256 	struct list_head sibling;	/* linkage in my parent's children list */
1257 	struct task_struct *group_leader;	/* threadgroup leader */
1258 
1259 	/*
1260 	 * ptraced is the list of tasks this task is using ptrace on.
1261 	 * This includes both natural children and PTRACE_ATTACH targets.
1262 	 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1263 	 */
1264 	struct list_head ptraced;
1265 	struct list_head ptrace_entry;
1266 
1267 	/* PID/PID hash table linkage. */
1268 	struct pid_link pids[PIDTYPE_MAX];
1269 	struct list_head thread_group;
1270 
1271 	struct completion *vfork_done;		/* for vfork() */
1272 	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
1273 	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
1274 
1275 	cputime_t utime, stime, utimescaled, stimescaled;
1276 	cputime_t gtime;
1277 #ifndef CONFIG_VIRT_CPU_ACCOUNTING
1278 	cputime_t prev_utime, prev_stime;
1279 #endif
1280 	unsigned long nvcsw, nivcsw; /* context switch counts */
1281 	struct timespec start_time; 		/* monotonic time */
1282 	struct timespec real_start_time;	/* boot based time */
1283 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1284 	unsigned long min_flt, maj_flt;
1285 
1286 	struct task_cputime cputime_expires;
1287 	struct list_head cpu_timers[3];
1288 
1289 /* process credentials */
1290 	const struct cred *real_cred;	/* objective and real subjective task
1291 					 * credentials (COW) */
1292 	const struct cred *cred;	/* effective (overridable) subjective task
1293 					 * credentials (COW) */
1294 	struct mutex cred_guard_mutex;	/* guard against foreign influences on
1295 					 * credential calculations
1296 					 * (notably. ptrace) */
1297 	struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */
1298 
1299 	char comm[TASK_COMM_LEN]; /* executable name excluding path
1300 				     - access with [gs]et_task_comm (which lock
1301 				       it with task_lock())
1302 				     - initialized normally by setup_new_exec */
1303 /* file system info */
1304 	int link_count, total_link_count;
1305 #ifdef CONFIG_SYSVIPC
1306 /* ipc stuff */
1307 	struct sysv_sem sysvsem;
1308 #endif
1309 #ifdef CONFIG_DETECT_HUNG_TASK
1310 /* hung task detection */
1311 	unsigned long last_switch_count;
1312 #endif
1313 /* CPU-specific state of this task */
1314 	struct thread_struct thread;
1315 /* filesystem information */
1316 	struct fs_struct *fs;
1317 /* open file information */
1318 	struct files_struct *files;
1319 /* namespaces */
1320 	struct nsproxy *nsproxy;
1321 /* signal handlers */
1322 	struct signal_struct *signal;
1323 	struct sighand_struct *sighand;
1324 
1325 	sigset_t blocked, real_blocked;
1326 	sigset_t saved_sigmask;	/* restored if set_restore_sigmask() was used */
1327 	struct sigpending pending;
1328 
1329 	unsigned long sas_ss_sp;
1330 	size_t sas_ss_size;
1331 	int (*notifier)(void *priv);
1332 	void *notifier_data;
1333 	sigset_t *notifier_mask;
1334 	struct audit_context *audit_context;
1335 #ifdef CONFIG_AUDITSYSCALL
1336 	uid_t loginuid;
1337 	unsigned int sessionid;
1338 #endif
1339 	seccomp_t seccomp;
1340 
1341 /* Thread group tracking */
1342    	u32 parent_exec_id;
1343    	u32 self_exec_id;
1344 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1345  * mempolicy */
1346 	spinlock_t alloc_lock;
1347 
1348 #ifdef CONFIG_GENERIC_HARDIRQS
1349 	/* IRQ handler threads */
1350 	struct irqaction *irqaction;
1351 #endif
1352 
1353 	/* Protection of the PI data structures: */
1354 	raw_spinlock_t pi_lock;
1355 
1356 #ifdef CONFIG_RT_MUTEXES
1357 	/* PI waiters blocked on a rt_mutex held by this task */
1358 	struct plist_head pi_waiters;
1359 	/* Deadlock detection and priority inheritance handling */
1360 	struct rt_mutex_waiter *pi_blocked_on;
1361 #endif
1362 
1363 #ifdef CONFIG_DEBUG_MUTEXES
1364 	/* mutex deadlock detection */
1365 	struct mutex_waiter *blocked_on;
1366 #endif
1367 #ifdef CONFIG_TRACE_IRQFLAGS
1368 	unsigned int irq_events;
1369 	unsigned long hardirq_enable_ip;
1370 	unsigned long hardirq_disable_ip;
1371 	unsigned int hardirq_enable_event;
1372 	unsigned int hardirq_disable_event;
1373 	int hardirqs_enabled;
1374 	int hardirq_context;
1375 	unsigned long softirq_disable_ip;
1376 	unsigned long softirq_enable_ip;
1377 	unsigned int softirq_disable_event;
1378 	unsigned int softirq_enable_event;
1379 	int softirqs_enabled;
1380 	int softirq_context;
1381 #endif
1382 #ifdef CONFIG_LOCKDEP
1383 # define MAX_LOCK_DEPTH 48UL
1384 	u64 curr_chain_key;
1385 	int lockdep_depth;
1386 	unsigned int lockdep_recursion;
1387 	struct held_lock held_locks[MAX_LOCK_DEPTH];
1388 	gfp_t lockdep_reclaim_gfp;
1389 #endif
1390 
1391 /* journalling filesystem info */
1392 	void *journal_info;
1393 
1394 /* stacked block device info */
1395 	struct bio_list *bio_list;
1396 
1397 /* VM state */
1398 	struct reclaim_state *reclaim_state;
1399 
1400 	struct backing_dev_info *backing_dev_info;
1401 
1402 	struct io_context *io_context;
1403 
1404 	unsigned long ptrace_message;
1405 	siginfo_t *last_siginfo; /* For ptrace use.  */
1406 	struct task_io_accounting ioac;
1407 #if defined(CONFIG_TASK_XACCT)
1408 	u64 acct_rss_mem1;	/* accumulated rss usage */
1409 	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1410 	cputime_t acct_timexpd;	/* stime + utime since last update */
1411 #endif
1412 #ifdef CONFIG_CPUSETS
1413 	nodemask_t mems_allowed;	/* Protected by alloc_lock */
1414 	int mems_allowed_change_disable;
1415 	int cpuset_mem_spread_rotor;
1416 	int cpuset_slab_spread_rotor;
1417 #endif
1418 #ifdef CONFIG_CGROUPS
1419 	/* Control Group info protected by css_set_lock */
1420 	struct css_set *cgroups;
1421 	/* cg_list protected by css_set_lock and tsk->alloc_lock */
1422 	struct list_head cg_list;
1423 #endif
1424 #ifdef CONFIG_FUTEX
1425 	struct robust_list_head __user *robust_list;
1426 #ifdef CONFIG_COMPAT
1427 	struct compat_robust_list_head __user *compat_robust_list;
1428 #endif
1429 	struct list_head pi_state_list;
1430 	struct futex_pi_state *pi_state_cache;
1431 #endif
1432 #ifdef CONFIG_PERF_EVENTS
1433 	struct perf_event_context *perf_event_ctxp;
1434 	struct mutex perf_event_mutex;
1435 	struct list_head perf_event_list;
1436 #endif
1437 #ifdef CONFIG_NUMA
1438 	struct mempolicy *mempolicy;	/* Protected by alloc_lock */
1439 	short il_next;
1440 #endif
1441 	atomic_t fs_excl;	/* holding fs exclusive resources */
1442 	struct rcu_head rcu;
1443 
1444 	/*
1445 	 * cache last used pipe for splice
1446 	 */
1447 	struct pipe_inode_info *splice_pipe;
1448 #ifdef	CONFIG_TASK_DELAY_ACCT
1449 	struct task_delay_info *delays;
1450 #endif
1451 #ifdef CONFIG_FAULT_INJECTION
1452 	int make_it_fail;
1453 #endif
1454 	struct prop_local_single dirties;
1455 #ifdef CONFIG_LATENCYTOP
1456 	int latency_record_count;
1457 	struct latency_record latency_record[LT_SAVECOUNT];
1458 #endif
1459 	/*
1460 	 * time slack values; these are used to round up poll() and
1461 	 * select() etc timeout values. These are in nanoseconds.
1462 	 */
1463 	unsigned long timer_slack_ns;
1464 	unsigned long default_timer_slack_ns;
1465 
1466 	struct list_head	*scm_work_list;
1467 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1468 	/* Index of current stored address in ret_stack */
1469 	int curr_ret_stack;
1470 	/* Stack of return addresses for return function tracing */
1471 	struct ftrace_ret_stack	*ret_stack;
1472 	/* time stamp for last schedule */
1473 	unsigned long long ftrace_timestamp;
1474 	/*
1475 	 * Number of functions that haven't been traced
1476 	 * because of depth overrun.
1477 	 */
1478 	atomic_t trace_overrun;
1479 	/* Pause for the tracing */
1480 	atomic_t tracing_graph_pause;
1481 #endif
1482 #ifdef CONFIG_TRACING
1483 	/* state flags for use by tracers */
1484 	unsigned long trace;
1485 	/* bitmask of trace recursion */
1486 	unsigned long trace_recursion;
1487 #endif /* CONFIG_TRACING */
1488 #ifdef CONFIG_CGROUP_MEM_RES_CTLR /* memcg uses this to do batch job */
1489 	struct memcg_batch_info {
1490 		int do_batch;	/* incremented when batch uncharge started */
1491 		struct mem_cgroup *memcg; /* target memcg of uncharge */
1492 		unsigned long bytes; 		/* uncharged usage */
1493 		unsigned long memsw_bytes; /* uncharged mem+swap usage */
1494 	} memcg_batch;
1495 #endif
1496 };
1497 
1498 /* Future-safe accessor for struct task_struct's cpus_allowed. */
1499 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1500 
1501 /*
1502  * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1503  * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1504  * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1505  * values are inverted: lower p->prio value means higher priority.
1506  *
1507  * The MAX_USER_RT_PRIO value allows the actual maximum
1508  * RT priority to be separate from the value exported to
1509  * user-space.  This allows kernel threads to set their
1510  * priority to a value higher than any user task. Note:
1511  * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1512  */
1513 
1514 #define MAX_USER_RT_PRIO	100
1515 #define MAX_RT_PRIO		MAX_USER_RT_PRIO
1516 
1517 #define MAX_PRIO		(MAX_RT_PRIO + 40)
1518 #define DEFAULT_PRIO		(MAX_RT_PRIO + 20)
1519 
1520 static inline int rt_prio(int prio)
1521 {
1522 	if (unlikely(prio < MAX_RT_PRIO))
1523 		return 1;
1524 	return 0;
1525 }
1526 
1527 static inline int rt_task(struct task_struct *p)
1528 {
1529 	return rt_prio(p->prio);
1530 }
1531 
1532 static inline struct pid *task_pid(struct task_struct *task)
1533 {
1534 	return task->pids[PIDTYPE_PID].pid;
1535 }
1536 
1537 static inline struct pid *task_tgid(struct task_struct *task)
1538 {
1539 	return task->group_leader->pids[PIDTYPE_PID].pid;
1540 }
1541 
1542 /*
1543  * Without tasklist or rcu lock it is not safe to dereference
1544  * the result of task_pgrp/task_session even if task == current,
1545  * we can race with another thread doing sys_setsid/sys_setpgid.
1546  */
1547 static inline struct pid *task_pgrp(struct task_struct *task)
1548 {
1549 	return task->group_leader->pids[PIDTYPE_PGID].pid;
1550 }
1551 
1552 static inline struct pid *task_session(struct task_struct *task)
1553 {
1554 	return task->group_leader->pids[PIDTYPE_SID].pid;
1555 }
1556 
1557 struct pid_namespace;
1558 
1559 /*
1560  * the helpers to get the task's different pids as they are seen
1561  * from various namespaces
1562  *
1563  * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1564  * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1565  *                     current.
1566  * task_xid_nr_ns()  : id seen from the ns specified;
1567  *
1568  * set_task_vxid()   : assigns a virtual id to a task;
1569  *
1570  * see also pid_nr() etc in include/linux/pid.h
1571  */
1572 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1573 			struct pid_namespace *ns);
1574 
1575 static inline pid_t task_pid_nr(struct task_struct *tsk)
1576 {
1577 	return tsk->pid;
1578 }
1579 
1580 static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1581 					struct pid_namespace *ns)
1582 {
1583 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1584 }
1585 
1586 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1587 {
1588 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1589 }
1590 
1591 
1592 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1593 {
1594 	return tsk->tgid;
1595 }
1596 
1597 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1598 
1599 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1600 {
1601 	return pid_vnr(task_tgid(tsk));
1602 }
1603 
1604 
1605 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1606 					struct pid_namespace *ns)
1607 {
1608 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1609 }
1610 
1611 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1612 {
1613 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1614 }
1615 
1616 
1617 static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1618 					struct pid_namespace *ns)
1619 {
1620 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1621 }
1622 
1623 static inline pid_t task_session_vnr(struct task_struct *tsk)
1624 {
1625 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1626 }
1627 
1628 /* obsolete, do not use */
1629 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1630 {
1631 	return task_pgrp_nr_ns(tsk, &init_pid_ns);
1632 }
1633 
1634 /**
1635  * pid_alive - check that a task structure is not stale
1636  * @p: Task structure to be checked.
1637  *
1638  * Test if a process is not yet dead (at most zombie state)
1639  * If pid_alive fails, then pointers within the task structure
1640  * can be stale and must not be dereferenced.
1641  */
1642 static inline int pid_alive(struct task_struct *p)
1643 {
1644 	return p->pids[PIDTYPE_PID].pid != NULL;
1645 }
1646 
1647 /**
1648  * is_global_init - check if a task structure is init
1649  * @tsk: Task structure to be checked.
1650  *
1651  * Check if a task structure is the first user space task the kernel created.
1652  */
1653 static inline int is_global_init(struct task_struct *tsk)
1654 {
1655 	return tsk->pid == 1;
1656 }
1657 
1658 /*
1659  * is_container_init:
1660  * check whether in the task is init in its own pid namespace.
1661  */
1662 extern int is_container_init(struct task_struct *tsk);
1663 
1664 extern struct pid *cad_pid;
1665 
1666 extern void free_task(struct task_struct *tsk);
1667 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1668 
1669 extern void __put_task_struct(struct task_struct *t);
1670 
1671 static inline void put_task_struct(struct task_struct *t)
1672 {
1673 	if (atomic_dec_and_test(&t->usage))
1674 		__put_task_struct(t);
1675 }
1676 
1677 extern void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1678 extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1679 
1680 /*
1681  * Per process flags
1682  */
1683 #define PF_ALIGNWARN	0x00000001	/* Print alignment warning msgs */
1684 					/* Not implemented yet, only for 486*/
1685 #define PF_STARTING	0x00000002	/* being created */
1686 #define PF_EXITING	0x00000004	/* getting shut down */
1687 #define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
1688 #define PF_VCPU		0x00000010	/* I'm a virtual CPU */
1689 #define PF_WQ_WORKER	0x00000020	/* I'm a workqueue worker */
1690 #define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
1691 #define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
1692 #define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
1693 #define PF_DUMPCORE	0x00000200	/* dumped core */
1694 #define PF_SIGNALED	0x00000400	/* killed by a signal */
1695 #define PF_MEMALLOC	0x00000800	/* Allocating memory */
1696 #define PF_FLUSHER	0x00001000	/* responsible for disk writeback */
1697 #define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
1698 #define PF_FREEZING	0x00004000	/* freeze in progress. do not account to load */
1699 #define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
1700 #define PF_FROZEN	0x00010000	/* frozen for system suspend */
1701 #define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
1702 #define PF_KSWAPD	0x00040000	/* I am kswapd */
1703 #define PF_OOM_ORIGIN	0x00080000	/* Allocating much memory to others */
1704 #define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
1705 #define PF_KTHREAD	0x00200000	/* I am a kernel thread */
1706 #define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
1707 #define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
1708 #define PF_SPREAD_PAGE	0x01000000	/* Spread page cache over cpuset */
1709 #define PF_SPREAD_SLAB	0x02000000	/* Spread some slab caches over cpuset */
1710 #define PF_THREAD_BOUND	0x04000000	/* Thread bound to specific cpu */
1711 #define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
1712 #define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
1713 #define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
1714 #define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezeable */
1715 #define PF_FREEZER_NOSIG 0x80000000	/* Freezer won't send signals to it */
1716 
1717 /*
1718  * Only the _current_ task can read/write to tsk->flags, but other
1719  * tasks can access tsk->flags in readonly mode for example
1720  * with tsk_used_math (like during threaded core dumping).
1721  * There is however an exception to this rule during ptrace
1722  * or during fork: the ptracer task is allowed to write to the
1723  * child->flags of its traced child (same goes for fork, the parent
1724  * can write to the child->flags), because we're guaranteed the
1725  * child is not running and in turn not changing child->flags
1726  * at the same time the parent does it.
1727  */
1728 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1729 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1730 #define clear_used_math() clear_stopped_child_used_math(current)
1731 #define set_used_math() set_stopped_child_used_math(current)
1732 #define conditional_stopped_child_used_math(condition, child) \
1733 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1734 #define conditional_used_math(condition) \
1735 	conditional_stopped_child_used_math(condition, current)
1736 #define copy_to_stopped_child_used_math(child) \
1737 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1738 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1739 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1740 #define used_math() tsk_used_math(current)
1741 
1742 #ifdef CONFIG_TREE_PREEMPT_RCU
1743 
1744 #define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */
1745 #define RCU_READ_UNLOCK_NEED_QS (1 << 1) /* RCU core needs CPU response. */
1746 
1747 static inline void rcu_copy_process(struct task_struct *p)
1748 {
1749 	p->rcu_read_lock_nesting = 0;
1750 	p->rcu_read_unlock_special = 0;
1751 	p->rcu_blocked_node = NULL;
1752 	INIT_LIST_HEAD(&p->rcu_node_entry);
1753 }
1754 
1755 #else
1756 
1757 static inline void rcu_copy_process(struct task_struct *p)
1758 {
1759 }
1760 
1761 #endif
1762 
1763 #ifdef CONFIG_SMP
1764 extern int set_cpus_allowed_ptr(struct task_struct *p,
1765 				const struct cpumask *new_mask);
1766 #else
1767 static inline int set_cpus_allowed_ptr(struct task_struct *p,
1768 				       const struct cpumask *new_mask)
1769 {
1770 	if (!cpumask_test_cpu(0, new_mask))
1771 		return -EINVAL;
1772 	return 0;
1773 }
1774 #endif
1775 
1776 #ifndef CONFIG_CPUMASK_OFFSTACK
1777 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1778 {
1779 	return set_cpus_allowed_ptr(p, &new_mask);
1780 }
1781 #endif
1782 
1783 /*
1784  * Do not use outside of architecture code which knows its limitations.
1785  *
1786  * sched_clock() has no promise of monotonicity or bounded drift between
1787  * CPUs, use (which you should not) requires disabling IRQs.
1788  *
1789  * Please use one of the three interfaces below.
1790  */
1791 extern unsigned long long notrace sched_clock(void);
1792 /*
1793  * See the comment in kernel/sched_clock.c
1794  */
1795 extern u64 cpu_clock(int cpu);
1796 extern u64 local_clock(void);
1797 extern u64 sched_clock_cpu(int cpu);
1798 
1799 
1800 extern void sched_clock_init(void);
1801 
1802 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1803 static inline void sched_clock_tick(void)
1804 {
1805 }
1806 
1807 static inline void sched_clock_idle_sleep_event(void)
1808 {
1809 }
1810 
1811 static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
1812 {
1813 }
1814 #else
1815 /*
1816  * Architectures can set this to 1 if they have specified
1817  * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
1818  * but then during bootup it turns out that sched_clock()
1819  * is reliable after all:
1820  */
1821 extern int sched_clock_stable;
1822 
1823 extern void sched_clock_tick(void);
1824 extern void sched_clock_idle_sleep_event(void);
1825 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1826 #endif
1827 
1828 extern unsigned long long
1829 task_sched_runtime(struct task_struct *task);
1830 extern unsigned long long thread_group_sched_runtime(struct task_struct *task);
1831 
1832 /* sched_exec is called by processes performing an exec */
1833 #ifdef CONFIG_SMP
1834 extern void sched_exec(void);
1835 #else
1836 #define sched_exec()   {}
1837 #endif
1838 
1839 extern void sched_clock_idle_sleep_event(void);
1840 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1841 
1842 #ifdef CONFIG_HOTPLUG_CPU
1843 extern void move_task_off_dead_cpu(int dead_cpu, struct task_struct *p);
1844 extern void idle_task_exit(void);
1845 #else
1846 static inline void idle_task_exit(void) {}
1847 #endif
1848 
1849 extern void sched_idle_next(void);
1850 
1851 #if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1852 extern void wake_up_idle_cpu(int cpu);
1853 #else
1854 static inline void wake_up_idle_cpu(int cpu) { }
1855 #endif
1856 
1857 extern unsigned int sysctl_sched_latency;
1858 extern unsigned int sysctl_sched_min_granularity;
1859 extern unsigned int sysctl_sched_wakeup_granularity;
1860 extern unsigned int sysctl_sched_shares_ratelimit;
1861 extern unsigned int sysctl_sched_shares_thresh;
1862 extern unsigned int sysctl_sched_child_runs_first;
1863 
1864 enum sched_tunable_scaling {
1865 	SCHED_TUNABLESCALING_NONE,
1866 	SCHED_TUNABLESCALING_LOG,
1867 	SCHED_TUNABLESCALING_LINEAR,
1868 	SCHED_TUNABLESCALING_END,
1869 };
1870 extern enum sched_tunable_scaling sysctl_sched_tunable_scaling;
1871 
1872 #ifdef CONFIG_SCHED_DEBUG
1873 extern unsigned int sysctl_sched_migration_cost;
1874 extern unsigned int sysctl_sched_nr_migrate;
1875 extern unsigned int sysctl_sched_time_avg;
1876 extern unsigned int sysctl_timer_migration;
1877 
1878 int sched_proc_update_handler(struct ctl_table *table, int write,
1879 		void __user *buffer, size_t *length,
1880 		loff_t *ppos);
1881 #endif
1882 #ifdef CONFIG_SCHED_DEBUG
1883 static inline unsigned int get_sysctl_timer_migration(void)
1884 {
1885 	return sysctl_timer_migration;
1886 }
1887 #else
1888 static inline unsigned int get_sysctl_timer_migration(void)
1889 {
1890 	return 1;
1891 }
1892 #endif
1893 extern unsigned int sysctl_sched_rt_period;
1894 extern int sysctl_sched_rt_runtime;
1895 
1896 int sched_rt_handler(struct ctl_table *table, int write,
1897 		void __user *buffer, size_t *lenp,
1898 		loff_t *ppos);
1899 
1900 extern unsigned int sysctl_sched_compat_yield;
1901 
1902 #ifdef CONFIG_RT_MUTEXES
1903 extern int rt_mutex_getprio(struct task_struct *p);
1904 extern void rt_mutex_setprio(struct task_struct *p, int prio);
1905 extern void rt_mutex_adjust_pi(struct task_struct *p);
1906 #else
1907 static inline int rt_mutex_getprio(struct task_struct *p)
1908 {
1909 	return p->normal_prio;
1910 }
1911 # define rt_mutex_adjust_pi(p)		do { } while (0)
1912 #endif
1913 
1914 extern void set_user_nice(struct task_struct *p, long nice);
1915 extern int task_prio(const struct task_struct *p);
1916 extern int task_nice(const struct task_struct *p);
1917 extern int can_nice(const struct task_struct *p, const int nice);
1918 extern int task_curr(const struct task_struct *p);
1919 extern int idle_cpu(int cpu);
1920 extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1921 extern int sched_setscheduler_nocheck(struct task_struct *, int,
1922 				      struct sched_param *);
1923 extern struct task_struct *idle_task(int cpu);
1924 extern struct task_struct *curr_task(int cpu);
1925 extern void set_curr_task(int cpu, struct task_struct *p);
1926 
1927 void yield(void);
1928 
1929 /*
1930  * The default (Linux) execution domain.
1931  */
1932 extern struct exec_domain	default_exec_domain;
1933 
1934 union thread_union {
1935 	struct thread_info thread_info;
1936 	unsigned long stack[THREAD_SIZE/sizeof(long)];
1937 };
1938 
1939 #ifndef __HAVE_ARCH_KSTACK_END
1940 static inline int kstack_end(void *addr)
1941 {
1942 	/* Reliable end of stack detection:
1943 	 * Some APM bios versions misalign the stack
1944 	 */
1945 	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1946 }
1947 #endif
1948 
1949 extern union thread_union init_thread_union;
1950 extern struct task_struct init_task;
1951 
1952 extern struct   mm_struct init_mm;
1953 
1954 extern struct pid_namespace init_pid_ns;
1955 
1956 /*
1957  * find a task by one of its numerical ids
1958  *
1959  * find_task_by_pid_ns():
1960  *      finds a task by its pid in the specified namespace
1961  * find_task_by_vpid():
1962  *      finds a task by its virtual pid
1963  *
1964  * see also find_vpid() etc in include/linux/pid.h
1965  */
1966 
1967 extern struct task_struct *find_task_by_vpid(pid_t nr);
1968 extern struct task_struct *find_task_by_pid_ns(pid_t nr,
1969 		struct pid_namespace *ns);
1970 
1971 extern void __set_special_pids(struct pid *pid);
1972 
1973 /* per-UID process charging. */
1974 extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
1975 static inline struct user_struct *get_uid(struct user_struct *u)
1976 {
1977 	atomic_inc(&u->__count);
1978 	return u;
1979 }
1980 extern void free_uid(struct user_struct *);
1981 extern void release_uids(struct user_namespace *ns);
1982 
1983 #include <asm/current.h>
1984 
1985 extern void do_timer(unsigned long ticks);
1986 
1987 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1988 extern int wake_up_process(struct task_struct *tsk);
1989 extern void wake_up_new_task(struct task_struct *tsk,
1990 				unsigned long clone_flags);
1991 #ifdef CONFIG_SMP
1992  extern void kick_process(struct task_struct *tsk);
1993 #else
1994  static inline void kick_process(struct task_struct *tsk) { }
1995 #endif
1996 extern void sched_fork(struct task_struct *p, int clone_flags);
1997 extern void sched_dead(struct task_struct *p);
1998 
1999 extern void proc_caches_init(void);
2000 extern void flush_signals(struct task_struct *);
2001 extern void __flush_signals(struct task_struct *);
2002 extern void ignore_signals(struct task_struct *);
2003 extern void flush_signal_handlers(struct task_struct *, int force_default);
2004 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2005 
2006 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
2007 {
2008 	unsigned long flags;
2009 	int ret;
2010 
2011 	spin_lock_irqsave(&tsk->sighand->siglock, flags);
2012 	ret = dequeue_signal(tsk, mask, info);
2013 	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
2014 
2015 	return ret;
2016 }
2017 
2018 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
2019 			      sigset_t *mask);
2020 extern void unblock_all_signals(void);
2021 extern void release_task(struct task_struct * p);
2022 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2023 extern int force_sigsegv(int, struct task_struct *);
2024 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2025 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2026 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2027 extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
2028 extern int kill_pgrp(struct pid *pid, int sig, int priv);
2029 extern int kill_pid(struct pid *pid, int sig, int priv);
2030 extern int kill_proc_info(int, struct siginfo *, pid_t);
2031 extern int do_notify_parent(struct task_struct *, int);
2032 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2033 extern void force_sig(int, struct task_struct *);
2034 extern int send_sig(int, struct task_struct *, int);
2035 extern int zap_other_threads(struct task_struct *p);
2036 extern struct sigqueue *sigqueue_alloc(void);
2037 extern void sigqueue_free(struct sigqueue *);
2038 extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
2039 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2040 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
2041 
2042 static inline int kill_cad_pid(int sig, int priv)
2043 {
2044 	return kill_pid(cad_pid, sig, priv);
2045 }
2046 
2047 /* These can be the second arg to send_sig_info/send_group_sig_info.  */
2048 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
2049 #define SEND_SIG_PRIV	((struct siginfo *) 1)
2050 #define SEND_SIG_FORCED	((struct siginfo *) 2)
2051 
2052 /*
2053  * True if we are on the alternate signal stack.
2054  */
2055 static inline int on_sig_stack(unsigned long sp)
2056 {
2057 #ifdef CONFIG_STACK_GROWSUP
2058 	return sp >= current->sas_ss_sp &&
2059 		sp - current->sas_ss_sp < current->sas_ss_size;
2060 #else
2061 	return sp > current->sas_ss_sp &&
2062 		sp - current->sas_ss_sp <= current->sas_ss_size;
2063 #endif
2064 }
2065 
2066 static inline int sas_ss_flags(unsigned long sp)
2067 {
2068 	return (current->sas_ss_size == 0 ? SS_DISABLE
2069 		: on_sig_stack(sp) ? SS_ONSTACK : 0);
2070 }
2071 
2072 /*
2073  * Routines for handling mm_structs
2074  */
2075 extern struct mm_struct * mm_alloc(void);
2076 
2077 /* mmdrop drops the mm and the page tables */
2078 extern void __mmdrop(struct mm_struct *);
2079 static inline void mmdrop(struct mm_struct * mm)
2080 {
2081 	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2082 		__mmdrop(mm);
2083 }
2084 
2085 /* mmput gets rid of the mappings and all user-space */
2086 extern void mmput(struct mm_struct *);
2087 /* Grab a reference to a task's mm, if it is not already going away */
2088 extern struct mm_struct *get_task_mm(struct task_struct *task);
2089 /* Remove the current tasks stale references to the old mm_struct */
2090 extern void mm_release(struct task_struct *, struct mm_struct *);
2091 /* Allocate a new mm structure and copy contents from tsk->mm */
2092 extern struct mm_struct *dup_mm(struct task_struct *tsk);
2093 
2094 extern int copy_thread(unsigned long, unsigned long, unsigned long,
2095 			struct task_struct *, struct pt_regs *);
2096 extern void flush_thread(void);
2097 extern void exit_thread(void);
2098 
2099 extern void exit_files(struct task_struct *);
2100 extern void __cleanup_sighand(struct sighand_struct *);
2101 
2102 extern void exit_itimers(struct signal_struct *);
2103 extern void flush_itimer_signals(void);
2104 
2105 extern NORET_TYPE void do_group_exit(int);
2106 
2107 extern void daemonize(const char *, ...);
2108 extern int allow_signal(int);
2109 extern int disallow_signal(int);
2110 
2111 extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
2112 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
2113 struct task_struct *fork_idle(int);
2114 
2115 extern void set_task_comm(struct task_struct *tsk, char *from);
2116 extern char *get_task_comm(char *to, struct task_struct *tsk);
2117 
2118 #ifdef CONFIG_SMP
2119 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2120 #else
2121 static inline unsigned long wait_task_inactive(struct task_struct *p,
2122 					       long match_state)
2123 {
2124 	return 1;
2125 }
2126 #endif
2127 
2128 #define next_task(p) \
2129 	list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2130 
2131 #define for_each_process(p) \
2132 	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2133 
2134 extern bool current_is_single_threaded(void);
2135 
2136 /*
2137  * Careful: do_each_thread/while_each_thread is a double loop so
2138  *          'break' will not work as expected - use goto instead.
2139  */
2140 #define do_each_thread(g, t) \
2141 	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2142 
2143 #define while_each_thread(g, t) \
2144 	while ((t = next_thread(t)) != g)
2145 
2146 static inline int get_nr_threads(struct task_struct *tsk)
2147 {
2148 	return tsk->signal->nr_threads;
2149 }
2150 
2151 /* de_thread depends on thread_group_leader not being a pid based check */
2152 #define thread_group_leader(p)	(p == p->group_leader)
2153 
2154 /* Do to the insanities of de_thread it is possible for a process
2155  * to have the pid of the thread group leader without actually being
2156  * the thread group leader.  For iteration through the pids in proc
2157  * all we care about is that we have a task with the appropriate
2158  * pid, we don't actually care if we have the right task.
2159  */
2160 static inline int has_group_leader_pid(struct task_struct *p)
2161 {
2162 	return p->pid == p->tgid;
2163 }
2164 
2165 static inline
2166 int same_thread_group(struct task_struct *p1, struct task_struct *p2)
2167 {
2168 	return p1->tgid == p2->tgid;
2169 }
2170 
2171 static inline struct task_struct *next_thread(const struct task_struct *p)
2172 {
2173 	return list_entry_rcu(p->thread_group.next,
2174 			      struct task_struct, thread_group);
2175 }
2176 
2177 static inline int thread_group_empty(struct task_struct *p)
2178 {
2179 	return list_empty(&p->thread_group);
2180 }
2181 
2182 #define delay_group_leader(p) \
2183 		(thread_group_leader(p) && !thread_group_empty(p))
2184 
2185 static inline int task_detached(struct task_struct *p)
2186 {
2187 	return p->exit_signal == -1;
2188 }
2189 
2190 /*
2191  * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2192  * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2193  * pins the final release of task.io_context.  Also protects ->cpuset and
2194  * ->cgroup.subsys[].
2195  *
2196  * Nests both inside and outside of read_lock(&tasklist_lock).
2197  * It must not be nested with write_lock_irq(&tasklist_lock),
2198  * neither inside nor outside.
2199  */
2200 static inline void task_lock(struct task_struct *p)
2201 {
2202 	spin_lock(&p->alloc_lock);
2203 }
2204 
2205 static inline void task_unlock(struct task_struct *p)
2206 {
2207 	spin_unlock(&p->alloc_lock);
2208 }
2209 
2210 extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2211 							unsigned long *flags);
2212 
2213 static inline void unlock_task_sighand(struct task_struct *tsk,
2214 						unsigned long *flags)
2215 {
2216 	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2217 }
2218 
2219 #ifndef __HAVE_THREAD_FUNCTIONS
2220 
2221 #define task_thread_info(task)	((struct thread_info *)(task)->stack)
2222 #define task_stack_page(task)	((task)->stack)
2223 
2224 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2225 {
2226 	*task_thread_info(p) = *task_thread_info(org);
2227 	task_thread_info(p)->task = p;
2228 }
2229 
2230 static inline unsigned long *end_of_stack(struct task_struct *p)
2231 {
2232 	return (unsigned long *)(task_thread_info(p) + 1);
2233 }
2234 
2235 #endif
2236 
2237 static inline int object_is_on_stack(void *obj)
2238 {
2239 	void *stack = task_stack_page(current);
2240 
2241 	return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2242 }
2243 
2244 extern void thread_info_cache_init(void);
2245 
2246 #ifdef CONFIG_DEBUG_STACK_USAGE
2247 static inline unsigned long stack_not_used(struct task_struct *p)
2248 {
2249 	unsigned long *n = end_of_stack(p);
2250 
2251 	do { 	/* Skip over canary */
2252 		n++;
2253 	} while (!*n);
2254 
2255 	return (unsigned long)n - (unsigned long)end_of_stack(p);
2256 }
2257 #endif
2258 
2259 /* set thread flags in other task's structures
2260  * - see asm/thread_info.h for TIF_xxxx flags available
2261  */
2262 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2263 {
2264 	set_ti_thread_flag(task_thread_info(tsk), flag);
2265 }
2266 
2267 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2268 {
2269 	clear_ti_thread_flag(task_thread_info(tsk), flag);
2270 }
2271 
2272 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2273 {
2274 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2275 }
2276 
2277 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2278 {
2279 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2280 }
2281 
2282 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2283 {
2284 	return test_ti_thread_flag(task_thread_info(tsk), flag);
2285 }
2286 
2287 static inline void set_tsk_need_resched(struct task_struct *tsk)
2288 {
2289 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2290 }
2291 
2292 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2293 {
2294 	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2295 }
2296 
2297 static inline int test_tsk_need_resched(struct task_struct *tsk)
2298 {
2299 	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2300 }
2301 
2302 static inline int restart_syscall(void)
2303 {
2304 	set_tsk_thread_flag(current, TIF_SIGPENDING);
2305 	return -ERESTARTNOINTR;
2306 }
2307 
2308 static inline int signal_pending(struct task_struct *p)
2309 {
2310 	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2311 }
2312 
2313 static inline int __fatal_signal_pending(struct task_struct *p)
2314 {
2315 	return unlikely(sigismember(&p->pending.signal, SIGKILL));
2316 }
2317 
2318 static inline int fatal_signal_pending(struct task_struct *p)
2319 {
2320 	return signal_pending(p) && __fatal_signal_pending(p);
2321 }
2322 
2323 static inline int signal_pending_state(long state, struct task_struct *p)
2324 {
2325 	if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2326 		return 0;
2327 	if (!signal_pending(p))
2328 		return 0;
2329 
2330 	return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2331 }
2332 
2333 static inline int need_resched(void)
2334 {
2335 	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
2336 }
2337 
2338 /*
2339  * cond_resched() and cond_resched_lock(): latency reduction via
2340  * explicit rescheduling in places that are safe. The return
2341  * value indicates whether a reschedule was done in fact.
2342  * cond_resched_lock() will drop the spinlock before scheduling,
2343  * cond_resched_softirq() will enable bhs before scheduling.
2344  */
2345 extern int _cond_resched(void);
2346 
2347 #define cond_resched() ({			\
2348 	__might_sleep(__FILE__, __LINE__, 0);	\
2349 	_cond_resched();			\
2350 })
2351 
2352 extern int __cond_resched_lock(spinlock_t *lock);
2353 
2354 #ifdef CONFIG_PREEMPT
2355 #define PREEMPT_LOCK_OFFSET	PREEMPT_OFFSET
2356 #else
2357 #define PREEMPT_LOCK_OFFSET	0
2358 #endif
2359 
2360 #define cond_resched_lock(lock) ({				\
2361 	__might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);	\
2362 	__cond_resched_lock(lock);				\
2363 })
2364 
2365 extern int __cond_resched_softirq(void);
2366 
2367 #define cond_resched_softirq() ({				\
2368 	__might_sleep(__FILE__, __LINE__, SOFTIRQ_OFFSET);	\
2369 	__cond_resched_softirq();				\
2370 })
2371 
2372 /*
2373  * Does a critical section need to be broken due to another
2374  * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2375  * but a general need for low latency)
2376  */
2377 static inline int spin_needbreak(spinlock_t *lock)
2378 {
2379 #ifdef CONFIG_PREEMPT
2380 	return spin_is_contended(lock);
2381 #else
2382 	return 0;
2383 #endif
2384 }
2385 
2386 /*
2387  * Thread group CPU time accounting.
2388  */
2389 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2390 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2391 
2392 static inline void thread_group_cputime_init(struct signal_struct *sig)
2393 {
2394 	spin_lock_init(&sig->cputimer.lock);
2395 }
2396 
2397 /*
2398  * Reevaluate whether the task has signals pending delivery.
2399  * Wake the task if so.
2400  * This is required every time the blocked sigset_t changes.
2401  * callers must hold sighand->siglock.
2402  */
2403 extern void recalc_sigpending_and_wake(struct task_struct *t);
2404 extern void recalc_sigpending(void);
2405 
2406 extern void signal_wake_up(struct task_struct *t, int resume_stopped);
2407 
2408 /*
2409  * Wrappers for p->thread_info->cpu access. No-op on UP.
2410  */
2411 #ifdef CONFIG_SMP
2412 
2413 static inline unsigned int task_cpu(const struct task_struct *p)
2414 {
2415 	return task_thread_info(p)->cpu;
2416 }
2417 
2418 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2419 
2420 #else
2421 
2422 static inline unsigned int task_cpu(const struct task_struct *p)
2423 {
2424 	return 0;
2425 }
2426 
2427 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2428 {
2429 }
2430 
2431 #endif /* CONFIG_SMP */
2432 
2433 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2434 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2435 
2436 extern void normalize_rt_tasks(void);
2437 
2438 #ifdef CONFIG_CGROUP_SCHED
2439 
2440 extern struct task_group init_task_group;
2441 
2442 extern struct task_group *sched_create_group(struct task_group *parent);
2443 extern void sched_destroy_group(struct task_group *tg);
2444 extern void sched_move_task(struct task_struct *tsk);
2445 #ifdef CONFIG_FAIR_GROUP_SCHED
2446 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2447 extern unsigned long sched_group_shares(struct task_group *tg);
2448 #endif
2449 #ifdef CONFIG_RT_GROUP_SCHED
2450 extern int sched_group_set_rt_runtime(struct task_group *tg,
2451 				      long rt_runtime_us);
2452 extern long sched_group_rt_runtime(struct task_group *tg);
2453 extern int sched_group_set_rt_period(struct task_group *tg,
2454 				      long rt_period_us);
2455 extern long sched_group_rt_period(struct task_group *tg);
2456 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
2457 #endif
2458 #endif
2459 
2460 extern int task_can_switch_user(struct user_struct *up,
2461 					struct task_struct *tsk);
2462 
2463 #ifdef CONFIG_TASK_XACCT
2464 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2465 {
2466 	tsk->ioac.rchar += amt;
2467 }
2468 
2469 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2470 {
2471 	tsk->ioac.wchar += amt;
2472 }
2473 
2474 static inline void inc_syscr(struct task_struct *tsk)
2475 {
2476 	tsk->ioac.syscr++;
2477 }
2478 
2479 static inline void inc_syscw(struct task_struct *tsk)
2480 {
2481 	tsk->ioac.syscw++;
2482 }
2483 #else
2484 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2485 {
2486 }
2487 
2488 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2489 {
2490 }
2491 
2492 static inline void inc_syscr(struct task_struct *tsk)
2493 {
2494 }
2495 
2496 static inline void inc_syscw(struct task_struct *tsk)
2497 {
2498 }
2499 #endif
2500 
2501 #ifndef TASK_SIZE_OF
2502 #define TASK_SIZE_OF(tsk)	TASK_SIZE
2503 #endif
2504 
2505 /*
2506  * Call the function if the target task is executing on a CPU right now:
2507  */
2508 extern void task_oncpu_function_call(struct task_struct *p,
2509 				     void (*func) (void *info), void *info);
2510 
2511 
2512 #ifdef CONFIG_MM_OWNER
2513 extern void mm_update_next_owner(struct mm_struct *mm);
2514 extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2515 #else
2516 static inline void mm_update_next_owner(struct mm_struct *mm)
2517 {
2518 }
2519 
2520 static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2521 {
2522 }
2523 #endif /* CONFIG_MM_OWNER */
2524 
2525 static inline unsigned long task_rlimit(const struct task_struct *tsk,
2526 		unsigned int limit)
2527 {
2528 	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur);
2529 }
2530 
2531 static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
2532 		unsigned int limit)
2533 {
2534 	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max);
2535 }
2536 
2537 static inline unsigned long rlimit(unsigned int limit)
2538 {
2539 	return task_rlimit(current, limit);
2540 }
2541 
2542 static inline unsigned long rlimit_max(unsigned int limit)
2543 {
2544 	return task_rlimit_max(current, limit);
2545 }
2546 
2547 #endif /* __KERNEL__ */
2548 
2549 #endif
2550