xref: /linux-6.15/include/linux/sched.h (revision edc7616c)
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 bts_context;
103 struct 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  */
121 extern unsigned long avenrun[];		/* Load averages */
122 extern 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 
136 extern unsigned long total_forks;
137 extern int nr_threads;
138 DECLARE_PER_CPU(unsigned long, process_counts);
139 extern int nr_processes(void);
140 extern unsigned long nr_running(void);
141 extern unsigned long nr_uninterruptible(void);
142 extern unsigned long nr_iowait(void);
143 extern unsigned long nr_iowait_cpu(void);
144 extern unsigned long this_cpu_load(void);
145 
146 
147 extern void calc_global_load(void);
148 
149 extern unsigned long get_parent_ip(unsigned long addr);
150 
151 struct seq_file;
152 struct cfs_rq;
153 struct task_group;
154 #ifdef CONFIG_SCHED_DEBUG
155 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
156 extern void proc_sched_set_task(struct task_struct *p);
157 extern void
158 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
159 #else
160 static inline void
161 proc_sched_show_task(struct task_struct *p, struct seq_file *m)
162 {
163 }
164 static inline void proc_sched_set_task(struct task_struct *p)
165 {
166 }
167 static inline void
168 print_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 
199 extern 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  */
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 extern void task_rq_unlock_wait(struct task_struct *p);
273 
274 extern cpumask_var_t nohz_cpu_mask;
275 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ)
276 extern int select_nohz_load_balancer(int cpu);
277 extern int get_nohz_load_balancer(void);
278 #else
279 static inline int select_nohz_load_balancer(int cpu)
280 {
281 	return 0;
282 }
283 #endif
284 
285 /*
286  * Only dump TASK_* tasks. (0 for all tasks)
287  */
288 extern void show_state_filter(unsigned long state_filter);
289 
290 static inline void show_state(void)
291 {
292 	show_state_filter(0);
293 }
294 
295 extern void show_regs(struct pt_regs *);
296 
297 /*
298  * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
299  * task), SP is the stack pointer of the first frame that should be shown in the back
300  * trace (or NULL if the entire call-chain of the task should be shown).
301  */
302 extern void show_stack(struct task_struct *task, unsigned long *sp);
303 
304 void io_schedule(void);
305 long io_schedule_timeout(long timeout);
306 
307 extern void cpu_init (void);
308 extern void trap_init(void);
309 extern void update_process_times(int user);
310 extern void scheduler_tick(void);
311 
312 extern void sched_show_task(struct task_struct *p);
313 
314 #ifdef CONFIG_DETECT_SOFTLOCKUP
315 extern void softlockup_tick(void);
316 extern void touch_softlockup_watchdog(void);
317 extern void touch_softlockup_watchdog_sync(void);
318 extern void touch_all_softlockup_watchdogs(void);
319 extern int proc_dosoftlockup_thresh(struct ctl_table *table, int write,
320 				    void __user *buffer,
321 				    size_t *lenp, loff_t *ppos);
322 extern unsigned int  softlockup_panic;
323 extern int softlockup_thresh;
324 #else
325 static inline void softlockup_tick(void)
326 {
327 }
328 static inline void touch_softlockup_watchdog(void)
329 {
330 }
331 static inline void touch_softlockup_watchdog_sync(void)
332 {
333 }
334 static inline void touch_all_softlockup_watchdogs(void)
335 {
336 }
337 #endif
338 
339 #ifdef CONFIG_DETECT_HUNG_TASK
340 extern unsigned int  sysctl_hung_task_panic;
341 extern unsigned long sysctl_hung_task_check_count;
342 extern unsigned long sysctl_hung_task_timeout_secs;
343 extern unsigned long sysctl_hung_task_warnings;
344 extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
345 					 void __user *buffer,
346 					 size_t *lenp, loff_t *ppos);
347 #endif
348 
349 /* Attach to any functions which should be ignored in wchan output. */
350 #define __sched		__attribute__((__section__(".sched.text")))
351 
352 /* Linker adds these: start and end of __sched functions */
353 extern char __sched_text_start[], __sched_text_end[];
354 
355 /* Is this address in the __sched functions? */
356 extern int in_sched_functions(unsigned long addr);
357 
358 #define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
359 extern signed long schedule_timeout(signed long timeout);
360 extern signed long schedule_timeout_interruptible(signed long timeout);
361 extern signed long schedule_timeout_killable(signed long timeout);
362 extern signed long schedule_timeout_uninterruptible(signed long timeout);
363 asmlinkage void schedule(void);
364 extern int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner);
365 
366 struct nsproxy;
367 struct user_namespace;
368 
369 /*
370  * Default maximum number of active map areas, this limits the number of vmas
371  * per mm struct. Users can overwrite this number by sysctl but there is a
372  * problem.
373  *
374  * When a program's coredump is generated as ELF format, a section is created
375  * per a vma. In ELF, the number of sections is represented in unsigned short.
376  * This means the number of sections should be smaller than 65535 at coredump.
377  * Because the kernel adds some informative sections to a image of program at
378  * generating coredump, we need some margin. The number of extra sections is
379  * 1-3 now and depends on arch. We use "5" as safe margin, here.
380  */
381 #define MAPCOUNT_ELF_CORE_MARGIN	(5)
382 #define DEFAULT_MAX_MAP_COUNT	(USHORT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
383 
384 extern int sysctl_max_map_count;
385 
386 #include <linux/aio.h>
387 
388 #ifdef CONFIG_MMU
389 extern void arch_pick_mmap_layout(struct mm_struct *mm);
390 extern unsigned long
391 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
392 		       unsigned long, unsigned long);
393 extern unsigned long
394 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
395 			  unsigned long len, unsigned long pgoff,
396 			  unsigned long flags);
397 extern void arch_unmap_area(struct mm_struct *, unsigned long);
398 extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
399 #else
400 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
401 #endif
402 
403 
404 extern void set_dumpable(struct mm_struct *mm, int value);
405 extern int get_dumpable(struct mm_struct *mm);
406 
407 /* mm flags */
408 /* dumpable bits */
409 #define MMF_DUMPABLE      0  /* core dump is permitted */
410 #define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
411 
412 #define MMF_DUMPABLE_BITS 2
413 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
414 
415 /* coredump filter bits */
416 #define MMF_DUMP_ANON_PRIVATE	2
417 #define MMF_DUMP_ANON_SHARED	3
418 #define MMF_DUMP_MAPPED_PRIVATE	4
419 #define MMF_DUMP_MAPPED_SHARED	5
420 #define MMF_DUMP_ELF_HEADERS	6
421 #define MMF_DUMP_HUGETLB_PRIVATE 7
422 #define MMF_DUMP_HUGETLB_SHARED  8
423 
424 #define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
425 #define MMF_DUMP_FILTER_BITS	7
426 #define MMF_DUMP_FILTER_MASK \
427 	(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
428 #define MMF_DUMP_FILTER_DEFAULT \
429 	((1 << MMF_DUMP_ANON_PRIVATE) |	(1 << MMF_DUMP_ANON_SHARED) |\
430 	 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
431 
432 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
433 # define MMF_DUMP_MASK_DEFAULT_ELF	(1 << MMF_DUMP_ELF_HEADERS)
434 #else
435 # define MMF_DUMP_MASK_DEFAULT_ELF	0
436 #endif
437 					/* leave room for more dump flags */
438 #define MMF_VM_MERGEABLE	16	/* KSM may merge identical pages */
439 
440 #define MMF_INIT_MASK		(MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
441 
442 struct sighand_struct {
443 	atomic_t		count;
444 	struct k_sigaction	action[_NSIG];
445 	spinlock_t		siglock;
446 	wait_queue_head_t	signalfd_wqh;
447 };
448 
449 struct pacct_struct {
450 	int			ac_flag;
451 	long			ac_exitcode;
452 	unsigned long		ac_mem;
453 	cputime_t		ac_utime, ac_stime;
454 	unsigned long		ac_minflt, ac_majflt;
455 };
456 
457 struct cpu_itimer {
458 	cputime_t expires;
459 	cputime_t incr;
460 	u32 error;
461 	u32 incr_error;
462 };
463 
464 /**
465  * struct task_cputime - collected CPU time counts
466  * @utime:		time spent in user mode, in &cputime_t units
467  * @stime:		time spent in kernel mode, in &cputime_t units
468  * @sum_exec_runtime:	total time spent on the CPU, in nanoseconds
469  *
470  * This structure groups together three kinds of CPU time that are
471  * tracked for threads and thread groups.  Most things considering
472  * CPU time want to group these counts together and treat all three
473  * of them in parallel.
474  */
475 struct task_cputime {
476 	cputime_t utime;
477 	cputime_t stime;
478 	unsigned long long sum_exec_runtime;
479 };
480 /* Alternate field names when used to cache expirations. */
481 #define prof_exp	stime
482 #define virt_exp	utime
483 #define sched_exp	sum_exec_runtime
484 
485 #define INIT_CPUTIME	\
486 	(struct task_cputime) {					\
487 		.utime = cputime_zero,				\
488 		.stime = cputime_zero,				\
489 		.sum_exec_runtime = 0,				\
490 	}
491 
492 /*
493  * Disable preemption until the scheduler is running.
494  * Reset by start_kernel()->sched_init()->init_idle().
495  *
496  * We include PREEMPT_ACTIVE to avoid cond_resched() from working
497  * before the scheduler is active -- see should_resched().
498  */
499 #define INIT_PREEMPT_COUNT	(1 + PREEMPT_ACTIVE)
500 
501 /**
502  * struct thread_group_cputimer - thread group interval timer counts
503  * @cputime:		thread group interval timers.
504  * @running:		non-zero when there are timers running and
505  * 			@cputime receives updates.
506  * @lock:		lock for fields in this struct.
507  *
508  * This structure contains the version of task_cputime, above, that is
509  * used for thread group CPU timer calculations.
510  */
511 struct thread_group_cputimer {
512 	struct task_cputime cputime;
513 	int running;
514 	spinlock_t lock;
515 };
516 
517 /*
518  * NOTE! "signal_struct" does not have it's own
519  * locking, because a shared signal_struct always
520  * implies a shared sighand_struct, so locking
521  * sighand_struct is always a proper superset of
522  * the locking of signal_struct.
523  */
524 struct signal_struct {
525 	atomic_t		count;
526 	atomic_t		live;
527 
528 	wait_queue_head_t	wait_chldexit;	/* for wait4() */
529 
530 	/* current thread group signal load-balancing target: */
531 	struct task_struct	*curr_target;
532 
533 	/* shared signal handling: */
534 	struct sigpending	shared_pending;
535 
536 	/* thread group exit support */
537 	int			group_exit_code;
538 	/* overloaded:
539 	 * - notify group_exit_task when ->count is equal to notify_count
540 	 * - everyone except group_exit_task is stopped during signal delivery
541 	 *   of fatal signals, group_exit_task processes the signal.
542 	 */
543 	int			notify_count;
544 	struct task_struct	*group_exit_task;
545 
546 	/* thread group stop support, overloads group_exit_code too */
547 	int			group_stop_count;
548 	unsigned int		flags; /* see SIGNAL_* flags below */
549 
550 	/* POSIX.1b Interval Timers */
551 	struct list_head posix_timers;
552 
553 	/* ITIMER_REAL timer for the process */
554 	struct hrtimer real_timer;
555 	struct pid *leader_pid;
556 	ktime_t it_real_incr;
557 
558 	/*
559 	 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
560 	 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
561 	 * values are defined to 0 and 1 respectively
562 	 */
563 	struct cpu_itimer it[2];
564 
565 	/*
566 	 * Thread group totals for process CPU timers.
567 	 * See thread_group_cputimer(), et al, for details.
568 	 */
569 	struct thread_group_cputimer cputimer;
570 
571 	/* Earliest-expiration cache. */
572 	struct task_cputime cputime_expires;
573 
574 	struct list_head cpu_timers[3];
575 
576 	struct pid *tty_old_pgrp;
577 
578 	/* boolean value for session group leader */
579 	int leader;
580 
581 	struct tty_struct *tty; /* NULL if no tty */
582 
583 	/*
584 	 * Cumulative resource counters for dead threads in the group,
585 	 * and for reaped dead child processes forked by this group.
586 	 * Live threads maintain their own counters and add to these
587 	 * in __exit_signal, except for the group leader.
588 	 */
589 	cputime_t utime, stime, cutime, cstime;
590 	cputime_t gtime;
591 	cputime_t cgtime;
592 #ifndef CONFIG_VIRT_CPU_ACCOUNTING
593 	cputime_t prev_utime, prev_stime;
594 #endif
595 	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
596 	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
597 	unsigned long inblock, oublock, cinblock, coublock;
598 	unsigned long maxrss, cmaxrss;
599 	struct task_io_accounting ioac;
600 
601 	/*
602 	 * Cumulative ns of schedule CPU time fo dead threads in the
603 	 * group, not including a zombie group leader, (This only differs
604 	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
605 	 * other than jiffies.)
606 	 */
607 	unsigned long long sum_sched_runtime;
608 
609 	/*
610 	 * We don't bother to synchronize most readers of this at all,
611 	 * because there is no reader checking a limit that actually needs
612 	 * to get both rlim_cur and rlim_max atomically, and either one
613 	 * alone is a single word that can safely be read normally.
614 	 * getrlimit/setrlimit use task_lock(current->group_leader) to
615 	 * protect this instead of the siglock, because they really
616 	 * have no need to disable irqs.
617 	 */
618 	struct rlimit rlim[RLIM_NLIMITS];
619 
620 #ifdef CONFIG_BSD_PROCESS_ACCT
621 	struct pacct_struct pacct;	/* per-process accounting information */
622 #endif
623 #ifdef CONFIG_TASKSTATS
624 	struct taskstats *stats;
625 #endif
626 #ifdef CONFIG_AUDIT
627 	unsigned audit_tty;
628 	struct tty_audit_buf *tty_audit_buf;
629 #endif
630 
631 	int oom_adj;	/* OOM kill score adjustment (bit shift) */
632 };
633 
634 /* Context switch must be unlocked if interrupts are to be enabled */
635 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
636 # define __ARCH_WANT_UNLOCKED_CTXSW
637 #endif
638 
639 /*
640  * Bits in flags field of signal_struct.
641  */
642 #define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
643 #define SIGNAL_STOP_DEQUEUED	0x00000002 /* stop signal dequeued */
644 #define SIGNAL_STOP_CONTINUED	0x00000004 /* SIGCONT since WCONTINUED reap */
645 #define SIGNAL_GROUP_EXIT	0x00000008 /* group exit in progress */
646 /*
647  * Pending notifications to parent.
648  */
649 #define SIGNAL_CLD_STOPPED	0x00000010
650 #define SIGNAL_CLD_CONTINUED	0x00000020
651 #define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
652 
653 #define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */
654 
655 /* If true, all threads except ->group_exit_task have pending SIGKILL */
656 static inline int signal_group_exit(const struct signal_struct *sig)
657 {
658 	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
659 		(sig->group_exit_task != NULL);
660 }
661 
662 /*
663  * Some day this will be a full-fledged user tracking system..
664  */
665 struct user_struct {
666 	atomic_t __count;	/* reference count */
667 	atomic_t processes;	/* How many processes does this user have? */
668 	atomic_t files;		/* How many open files does this user have? */
669 	atomic_t sigpending;	/* How many pending signals does this user have? */
670 #ifdef CONFIG_INOTIFY_USER
671 	atomic_t inotify_watches; /* How many inotify watches does this user have? */
672 	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
673 #endif
674 #ifdef CONFIG_EPOLL
675 	atomic_t epoll_watches;	/* The number of file descriptors currently watched */
676 #endif
677 #ifdef CONFIG_POSIX_MQUEUE
678 	/* protected by mq_lock	*/
679 	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
680 #endif
681 	unsigned long locked_shm; /* How many pages of mlocked shm ? */
682 
683 #ifdef CONFIG_KEYS
684 	struct key *uid_keyring;	/* UID specific keyring */
685 	struct key *session_keyring;	/* UID's default session keyring */
686 #endif
687 
688 	/* Hash table maintenance information */
689 	struct hlist_node uidhash_node;
690 	uid_t uid;
691 	struct user_namespace *user_ns;
692 
693 #ifdef CONFIG_PERF_EVENTS
694 	atomic_long_t locked_vm;
695 #endif
696 };
697 
698 extern int uids_sysfs_init(void);
699 
700 extern struct user_struct *find_user(uid_t);
701 
702 extern struct user_struct root_user;
703 #define INIT_USER (&root_user)
704 
705 
706 struct backing_dev_info;
707 struct reclaim_state;
708 
709 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
710 struct sched_info {
711 	/* cumulative counters */
712 	unsigned long pcount;	      /* # of times run on this cpu */
713 	unsigned long long run_delay; /* time spent waiting on a runqueue */
714 
715 	/* timestamps */
716 	unsigned long long last_arrival,/* when we last ran on a cpu */
717 			   last_queued;	/* when we were last queued to run */
718 #ifdef CONFIG_SCHEDSTATS
719 	/* BKL stats */
720 	unsigned int bkl_count;
721 #endif
722 };
723 #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
724 
725 #ifdef CONFIG_TASK_DELAY_ACCT
726 struct task_delay_info {
727 	spinlock_t	lock;
728 	unsigned int	flags;	/* Private per-task flags */
729 
730 	/* For each stat XXX, add following, aligned appropriately
731 	 *
732 	 * struct timespec XXX_start, XXX_end;
733 	 * u64 XXX_delay;
734 	 * u32 XXX_count;
735 	 *
736 	 * Atomicity of updates to XXX_delay, XXX_count protected by
737 	 * single lock above (split into XXX_lock if contention is an issue).
738 	 */
739 
740 	/*
741 	 * XXX_count is incremented on every XXX operation, the delay
742 	 * associated with the operation is added to XXX_delay.
743 	 * XXX_delay contains the accumulated delay time in nanoseconds.
744 	 */
745 	struct timespec blkio_start, blkio_end;	/* Shared by blkio, swapin */
746 	u64 blkio_delay;	/* wait for sync block io completion */
747 	u64 swapin_delay;	/* wait for swapin block io completion */
748 	u32 blkio_count;	/* total count of the number of sync block */
749 				/* io operations performed */
750 	u32 swapin_count;	/* total count of the number of swapin block */
751 				/* io operations performed */
752 
753 	struct timespec freepages_start, freepages_end;
754 	u64 freepages_delay;	/* wait for memory reclaim */
755 	u32 freepages_count;	/* total count of memory reclaim */
756 };
757 #endif	/* CONFIG_TASK_DELAY_ACCT */
758 
759 static inline int sched_info_on(void)
760 {
761 #ifdef CONFIG_SCHEDSTATS
762 	return 1;
763 #elif defined(CONFIG_TASK_DELAY_ACCT)
764 	extern int delayacct_on;
765 	return delayacct_on;
766 #else
767 	return 0;
768 #endif
769 }
770 
771 enum cpu_idle_type {
772 	CPU_IDLE,
773 	CPU_NOT_IDLE,
774 	CPU_NEWLY_IDLE,
775 	CPU_MAX_IDLE_TYPES
776 };
777 
778 /*
779  * sched-domains (multiprocessor balancing) declarations:
780  */
781 
782 /*
783  * Increase resolution of nice-level calculations:
784  */
785 #define SCHED_LOAD_SHIFT	10
786 #define SCHED_LOAD_SCALE	(1L << SCHED_LOAD_SHIFT)
787 
788 #define SCHED_LOAD_SCALE_FUZZ	SCHED_LOAD_SCALE
789 
790 #ifdef CONFIG_SMP
791 #define SD_LOAD_BALANCE		0x0001	/* Do load balancing on this domain. */
792 #define SD_BALANCE_NEWIDLE	0x0002	/* Balance when about to become idle */
793 #define SD_BALANCE_EXEC		0x0004	/* Balance on exec */
794 #define SD_BALANCE_FORK		0x0008	/* Balance on fork, clone */
795 #define SD_BALANCE_WAKE		0x0010  /* Balance on wakeup */
796 #define SD_WAKE_AFFINE		0x0020	/* Wake task to waking CPU */
797 #define SD_PREFER_LOCAL		0x0040  /* Prefer to keep tasks local to this domain */
798 #define SD_SHARE_CPUPOWER	0x0080	/* Domain members share cpu power */
799 #define SD_POWERSAVINGS_BALANCE	0x0100	/* Balance for power savings */
800 #define SD_SHARE_PKG_RESOURCES	0x0200	/* Domain members share cpu pkg resources */
801 #define SD_SERIALIZE		0x0400	/* Only a single load balancing instance */
802 
803 #define SD_PREFER_SIBLING	0x1000	/* Prefer to place tasks in a sibling domain */
804 
805 enum powersavings_balance_level {
806 	POWERSAVINGS_BALANCE_NONE = 0,  /* No power saving load balance */
807 	POWERSAVINGS_BALANCE_BASIC,	/* Fill one thread/core/package
808 					 * first for long running threads
809 					 */
810 	POWERSAVINGS_BALANCE_WAKEUP,	/* Also bias task wakeups to semi-idle
811 					 * cpu package for power savings
812 					 */
813 	MAX_POWERSAVINGS_BALANCE_LEVELS
814 };
815 
816 extern int sched_mc_power_savings, sched_smt_power_savings;
817 
818 static inline int sd_balance_for_mc_power(void)
819 {
820 	if (sched_smt_power_savings)
821 		return SD_POWERSAVINGS_BALANCE;
822 
823 	if (!sched_mc_power_savings)
824 		return SD_PREFER_SIBLING;
825 
826 	return 0;
827 }
828 
829 static inline int sd_balance_for_package_power(void)
830 {
831 	if (sched_mc_power_savings | sched_smt_power_savings)
832 		return SD_POWERSAVINGS_BALANCE;
833 
834 	return SD_PREFER_SIBLING;
835 }
836 
837 /*
838  * Optimise SD flags for power savings:
839  * SD_BALANCE_NEWIDLE helps agressive task consolidation and power savings.
840  * Keep default SD flags if sched_{smt,mc}_power_saving=0
841  */
842 
843 static inline int sd_power_saving_flags(void)
844 {
845 	if (sched_mc_power_savings | sched_smt_power_savings)
846 		return SD_BALANCE_NEWIDLE;
847 
848 	return 0;
849 }
850 
851 struct sched_group {
852 	struct sched_group *next;	/* Must be a circular list */
853 
854 	/*
855 	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
856 	 * single CPU.
857 	 */
858 	unsigned int cpu_power;
859 
860 	/*
861 	 * The CPUs this group covers.
862 	 *
863 	 * NOTE: this field is variable length. (Allocated dynamically
864 	 * by attaching extra space to the end of the structure,
865 	 * depending on how many CPUs the kernel has booted up with)
866 	 *
867 	 * It is also be embedded into static data structures at build
868 	 * time. (See 'struct static_sched_group' in kernel/sched.c)
869 	 */
870 	unsigned long cpumask[0];
871 };
872 
873 static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
874 {
875 	return to_cpumask(sg->cpumask);
876 }
877 
878 enum sched_domain_level {
879 	SD_LV_NONE = 0,
880 	SD_LV_SIBLING,
881 	SD_LV_MC,
882 	SD_LV_CPU,
883 	SD_LV_NODE,
884 	SD_LV_ALLNODES,
885 	SD_LV_MAX
886 };
887 
888 struct sched_domain_attr {
889 	int relax_domain_level;
890 };
891 
892 #define SD_ATTR_INIT	(struct sched_domain_attr) {	\
893 	.relax_domain_level = -1,			\
894 }
895 
896 struct sched_domain {
897 	/* These fields must be setup */
898 	struct sched_domain *parent;	/* top domain must be null terminated */
899 	struct sched_domain *child;	/* bottom domain must be null terminated */
900 	struct sched_group *groups;	/* the balancing groups of the domain */
901 	unsigned long min_interval;	/* Minimum balance interval ms */
902 	unsigned long max_interval;	/* Maximum balance interval ms */
903 	unsigned int busy_factor;	/* less balancing by factor if busy */
904 	unsigned int imbalance_pct;	/* No balance until over watermark */
905 	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
906 	unsigned int busy_idx;
907 	unsigned int idle_idx;
908 	unsigned int newidle_idx;
909 	unsigned int wake_idx;
910 	unsigned int forkexec_idx;
911 	unsigned int smt_gain;
912 	int flags;			/* See SD_* */
913 	enum sched_domain_level level;
914 
915 	/* Runtime fields. */
916 	unsigned long last_balance;	/* init to jiffies. units in jiffies */
917 	unsigned int balance_interval;	/* initialise to 1. units in ms. */
918 	unsigned int nr_balance_failed; /* initialise to 0 */
919 
920 	u64 last_update;
921 
922 #ifdef CONFIG_SCHEDSTATS
923 	/* load_balance() stats */
924 	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
925 	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
926 	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
927 	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
928 	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
929 	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
930 	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
931 	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
932 
933 	/* Active load balancing */
934 	unsigned int alb_count;
935 	unsigned int alb_failed;
936 	unsigned int alb_pushed;
937 
938 	/* SD_BALANCE_EXEC stats */
939 	unsigned int sbe_count;
940 	unsigned int sbe_balanced;
941 	unsigned int sbe_pushed;
942 
943 	/* SD_BALANCE_FORK stats */
944 	unsigned int sbf_count;
945 	unsigned int sbf_balanced;
946 	unsigned int sbf_pushed;
947 
948 	/* try_to_wake_up() stats */
949 	unsigned int ttwu_wake_remote;
950 	unsigned int ttwu_move_affine;
951 	unsigned int ttwu_move_balance;
952 #endif
953 #ifdef CONFIG_SCHED_DEBUG
954 	char *name;
955 #endif
956 
957 	/*
958 	 * Span of all CPUs in this domain.
959 	 *
960 	 * NOTE: this field is variable length. (Allocated dynamically
961 	 * by attaching extra space to the end of the structure,
962 	 * depending on how many CPUs the kernel has booted up with)
963 	 *
964 	 * It is also be embedded into static data structures at build
965 	 * time. (See 'struct static_sched_domain' in kernel/sched.c)
966 	 */
967 	unsigned long span[0];
968 };
969 
970 static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
971 {
972 	return to_cpumask(sd->span);
973 }
974 
975 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
976 				    struct sched_domain_attr *dattr_new);
977 
978 /* Allocate an array of sched domains, for partition_sched_domains(). */
979 cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
980 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
981 
982 /* Test a flag in parent sched domain */
983 static inline int test_sd_parent(struct sched_domain *sd, int flag)
984 {
985 	if (sd->parent && (sd->parent->flags & flag))
986 		return 1;
987 
988 	return 0;
989 }
990 
991 unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu);
992 unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu);
993 
994 #else /* CONFIG_SMP */
995 
996 struct sched_domain_attr;
997 
998 static inline void
999 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1000 			struct sched_domain_attr *dattr_new)
1001 {
1002 }
1003 #endif	/* !CONFIG_SMP */
1004 
1005 
1006 struct io_context;			/* See blkdev.h */
1007 
1008 
1009 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1010 extern void prefetch_stack(struct task_struct *t);
1011 #else
1012 static inline void prefetch_stack(struct task_struct *t) { }
1013 #endif
1014 
1015 struct audit_context;		/* See audit.c */
1016 struct mempolicy;
1017 struct pipe_inode_info;
1018 struct uts_namespace;
1019 
1020 struct rq;
1021 struct sched_domain;
1022 
1023 /*
1024  * wake flags
1025  */
1026 #define WF_SYNC		0x01		/* waker goes to sleep after wakup */
1027 #define WF_FORK		0x02		/* child wakeup after fork */
1028 
1029 struct sched_class {
1030 	const struct sched_class *next;
1031 
1032 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int wakeup,
1033 			      bool head);
1034 	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int sleep);
1035 	void (*yield_task) (struct rq *rq);
1036 
1037 	void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
1038 
1039 	struct task_struct * (*pick_next_task) (struct rq *rq);
1040 	void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1041 
1042 #ifdef CONFIG_SMP
1043 	int  (*select_task_rq)(struct task_struct *p, int sd_flag, int flags);
1044 
1045 	void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
1046 	void (*post_schedule) (struct rq *this_rq);
1047 	void (*task_waking) (struct rq *this_rq, struct task_struct *task);
1048 	void (*task_woken) (struct rq *this_rq, struct task_struct *task);
1049 
1050 	void (*set_cpus_allowed)(struct task_struct *p,
1051 				 const struct cpumask *newmask);
1052 
1053 	void (*rq_online)(struct rq *rq);
1054 	void (*rq_offline)(struct rq *rq);
1055 #endif
1056 
1057 	void (*set_curr_task) (struct rq *rq);
1058 	void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1059 	void (*task_fork) (struct task_struct *p);
1060 
1061 	void (*switched_from) (struct rq *this_rq, struct task_struct *task,
1062 			       int running);
1063 	void (*switched_to) (struct rq *this_rq, struct task_struct *task,
1064 			     int running);
1065 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1066 			     int oldprio, int running);
1067 
1068 	unsigned int (*get_rr_interval) (struct rq *rq,
1069 					 struct task_struct *task);
1070 
1071 #ifdef CONFIG_FAIR_GROUP_SCHED
1072 	void (*moved_group) (struct task_struct *p, int on_rq);
1073 #endif
1074 };
1075 
1076 struct load_weight {
1077 	unsigned long weight, inv_weight;
1078 };
1079 
1080 /*
1081  * CFS stats for a schedulable entity (task, task-group etc)
1082  *
1083  * Current field usage histogram:
1084  *
1085  *     4 se->block_start
1086  *     4 se->run_node
1087  *     4 se->sleep_start
1088  *     6 se->load.weight
1089  */
1090 struct sched_entity {
1091 	struct load_weight	load;		/* for load-balancing */
1092 	struct rb_node		run_node;
1093 	struct list_head	group_node;
1094 	unsigned int		on_rq;
1095 
1096 	u64			exec_start;
1097 	u64			sum_exec_runtime;
1098 	u64			vruntime;
1099 	u64			prev_sum_exec_runtime;
1100 
1101 	u64			last_wakeup;
1102 	u64			avg_overlap;
1103 
1104 	u64			nr_migrations;
1105 
1106 	u64			start_runtime;
1107 	u64			avg_wakeup;
1108 
1109 #ifdef CONFIG_SCHEDSTATS
1110 	u64			wait_start;
1111 	u64			wait_max;
1112 	u64			wait_count;
1113 	u64			wait_sum;
1114 	u64			iowait_count;
1115 	u64			iowait_sum;
1116 
1117 	u64			sleep_start;
1118 	u64			sleep_max;
1119 	s64			sum_sleep_runtime;
1120 
1121 	u64			block_start;
1122 	u64			block_max;
1123 	u64			exec_max;
1124 	u64			slice_max;
1125 
1126 	u64			nr_migrations_cold;
1127 	u64			nr_failed_migrations_affine;
1128 	u64			nr_failed_migrations_running;
1129 	u64			nr_failed_migrations_hot;
1130 	u64			nr_forced_migrations;
1131 
1132 	u64			nr_wakeups;
1133 	u64			nr_wakeups_sync;
1134 	u64			nr_wakeups_migrate;
1135 	u64			nr_wakeups_local;
1136 	u64			nr_wakeups_remote;
1137 	u64			nr_wakeups_affine;
1138 	u64			nr_wakeups_affine_attempts;
1139 	u64			nr_wakeups_passive;
1140 	u64			nr_wakeups_idle;
1141 #endif
1142 
1143 #ifdef CONFIG_FAIR_GROUP_SCHED
1144 	struct sched_entity	*parent;
1145 	/* rq on which this entity is (to be) queued: */
1146 	struct cfs_rq		*cfs_rq;
1147 	/* rq "owned" by this entity/group: */
1148 	struct cfs_rq		*my_q;
1149 #endif
1150 };
1151 
1152 struct sched_rt_entity {
1153 	struct list_head run_list;
1154 	unsigned long timeout;
1155 	unsigned int time_slice;
1156 	int nr_cpus_allowed;
1157 
1158 	struct sched_rt_entity *back;
1159 #ifdef CONFIG_RT_GROUP_SCHED
1160 	struct sched_rt_entity	*parent;
1161 	/* rq on which this entity is (to be) queued: */
1162 	struct rt_rq		*rt_rq;
1163 	/* rq "owned" by this entity/group: */
1164 	struct rt_rq		*my_q;
1165 #endif
1166 };
1167 
1168 struct rcu_node;
1169 
1170 struct task_struct {
1171 	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
1172 	void *stack;
1173 	atomic_t usage;
1174 	unsigned int flags;	/* per process flags, defined below */
1175 	unsigned int ptrace;
1176 
1177 	int lock_depth;		/* BKL lock depth */
1178 
1179 #ifdef CONFIG_SMP
1180 #ifdef __ARCH_WANT_UNLOCKED_CTXSW
1181 	int oncpu;
1182 #endif
1183 #endif
1184 
1185 	int prio, static_prio, normal_prio;
1186 	unsigned int rt_priority;
1187 	const struct sched_class *sched_class;
1188 	struct sched_entity se;
1189 	struct sched_rt_entity rt;
1190 
1191 #ifdef CONFIG_PREEMPT_NOTIFIERS
1192 	/* list of struct preempt_notifier: */
1193 	struct hlist_head preempt_notifiers;
1194 #endif
1195 
1196 	/*
1197 	 * fpu_counter contains the number of consecutive context switches
1198 	 * that the FPU is used. If this is over a threshold, the lazy fpu
1199 	 * saving becomes unlazy to save the trap. This is an unsigned char
1200 	 * so that after 256 times the counter wraps and the behavior turns
1201 	 * lazy again; this to deal with bursty apps that only use FPU for
1202 	 * a short time
1203 	 */
1204 	unsigned char fpu_counter;
1205 #ifdef CONFIG_BLK_DEV_IO_TRACE
1206 	unsigned int btrace_seq;
1207 #endif
1208 
1209 	unsigned int policy;
1210 	cpumask_t cpus_allowed;
1211 
1212 #ifdef CONFIG_TREE_PREEMPT_RCU
1213 	int rcu_read_lock_nesting;
1214 	char rcu_read_unlock_special;
1215 	struct rcu_node *rcu_blocked_node;
1216 	struct list_head rcu_node_entry;
1217 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1218 
1219 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1220 	struct sched_info sched_info;
1221 #endif
1222 
1223 	struct list_head tasks;
1224 	struct plist_node pushable_tasks;
1225 
1226 	struct mm_struct *mm, *active_mm;
1227 #if defined(SPLIT_RSS_COUNTING)
1228 	struct task_rss_stat	rss_stat;
1229 #endif
1230 /* task state */
1231 	int exit_state;
1232 	int exit_code, exit_signal;
1233 	int pdeath_signal;  /*  The signal sent when the parent dies  */
1234 	/* ??? */
1235 	unsigned int personality;
1236 	unsigned did_exec:1;
1237 	unsigned in_execve:1;	/* Tell the LSMs that the process is doing an
1238 				 * execve */
1239 	unsigned in_iowait:1;
1240 
1241 
1242 	/* Revert to default priority/policy when forking */
1243 	unsigned sched_reset_on_fork:1;
1244 
1245 	pid_t pid;
1246 	pid_t tgid;
1247 
1248 #ifdef CONFIG_CC_STACKPROTECTOR
1249 	/* Canary value for the -fstack-protector gcc feature */
1250 	unsigned long stack_canary;
1251 #endif
1252 
1253 	/*
1254 	 * pointers to (original) parent process, youngest child, younger sibling,
1255 	 * older sibling, respectively.  (p->father can be replaced with
1256 	 * p->real_parent->pid)
1257 	 */
1258 	struct task_struct *real_parent; /* real parent process */
1259 	struct task_struct *parent; /* recipient of SIGCHLD, wait4() reports */
1260 	/*
1261 	 * children/sibling forms the list of my natural children
1262 	 */
1263 	struct list_head children;	/* list of my children */
1264 	struct list_head sibling;	/* linkage in my parent's children list */
1265 	struct task_struct *group_leader;	/* threadgroup leader */
1266 
1267 	/*
1268 	 * ptraced is the list of tasks this task is using ptrace on.
1269 	 * This includes both natural children and PTRACE_ATTACH targets.
1270 	 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1271 	 */
1272 	struct list_head ptraced;
1273 	struct list_head ptrace_entry;
1274 
1275 	/*
1276 	 * This is the tracer handle for the ptrace BTS extension.
1277 	 * This field actually belongs to the ptracer task.
1278 	 */
1279 	struct bts_context *bts;
1280 
1281 	/* PID/PID hash table linkage. */
1282 	struct pid_link pids[PIDTYPE_MAX];
1283 	struct list_head thread_group;
1284 
1285 	struct completion *vfork_done;		/* for vfork() */
1286 	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
1287 	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
1288 
1289 	cputime_t utime, stime, utimescaled, stimescaled;
1290 	cputime_t gtime;
1291 #ifndef CONFIG_VIRT_CPU_ACCOUNTING
1292 	cputime_t prev_utime, prev_stime;
1293 #endif
1294 	unsigned long nvcsw, nivcsw; /* context switch counts */
1295 	struct timespec start_time; 		/* monotonic time */
1296 	struct timespec real_start_time;	/* boot based time */
1297 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1298 	unsigned long min_flt, maj_flt;
1299 
1300 	struct task_cputime cputime_expires;
1301 	struct list_head cpu_timers[3];
1302 
1303 /* process credentials */
1304 	const struct cred *real_cred;	/* objective and real subjective task
1305 					 * credentials (COW) */
1306 	const struct cred *cred;	/* effective (overridable) subjective task
1307 					 * credentials (COW) */
1308 	struct mutex cred_guard_mutex;	/* guard against foreign influences on
1309 					 * credential calculations
1310 					 * (notably. ptrace) */
1311 	struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */
1312 
1313 	char comm[TASK_COMM_LEN]; /* executable name excluding path
1314 				     - access with [gs]et_task_comm (which lock
1315 				       it with task_lock())
1316 				     - initialized normally by setup_new_exec */
1317 /* file system info */
1318 	int link_count, total_link_count;
1319 #ifdef CONFIG_SYSVIPC
1320 /* ipc stuff */
1321 	struct sysv_sem sysvsem;
1322 #endif
1323 #ifdef CONFIG_DETECT_HUNG_TASK
1324 /* hung task detection */
1325 	unsigned long last_switch_count;
1326 #endif
1327 /* CPU-specific state of this task */
1328 	struct thread_struct thread;
1329 /* filesystem information */
1330 	struct fs_struct *fs;
1331 /* open file information */
1332 	struct files_struct *files;
1333 /* namespaces */
1334 	struct nsproxy *nsproxy;
1335 /* signal handlers */
1336 	struct signal_struct *signal;
1337 	struct sighand_struct *sighand;
1338 
1339 	sigset_t blocked, real_blocked;
1340 	sigset_t saved_sigmask;	/* restored if set_restore_sigmask() was used */
1341 	struct sigpending pending;
1342 
1343 	unsigned long sas_ss_sp;
1344 	size_t sas_ss_size;
1345 	int (*notifier)(void *priv);
1346 	void *notifier_data;
1347 	sigset_t *notifier_mask;
1348 	struct audit_context *audit_context;
1349 #ifdef CONFIG_AUDITSYSCALL
1350 	uid_t loginuid;
1351 	unsigned int sessionid;
1352 #endif
1353 	seccomp_t seccomp;
1354 
1355 /* Thread group tracking */
1356    	u32 parent_exec_id;
1357    	u32 self_exec_id;
1358 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1359  * mempolicy */
1360 	spinlock_t alloc_lock;
1361 
1362 #ifdef CONFIG_GENERIC_HARDIRQS
1363 	/* IRQ handler threads */
1364 	struct irqaction *irqaction;
1365 #endif
1366 
1367 	/* Protection of the PI data structures: */
1368 	raw_spinlock_t pi_lock;
1369 
1370 #ifdef CONFIG_RT_MUTEXES
1371 	/* PI waiters blocked on a rt_mutex held by this task */
1372 	struct plist_head pi_waiters;
1373 	/* Deadlock detection and priority inheritance handling */
1374 	struct rt_mutex_waiter *pi_blocked_on;
1375 #endif
1376 
1377 #ifdef CONFIG_DEBUG_MUTEXES
1378 	/* mutex deadlock detection */
1379 	struct mutex_waiter *blocked_on;
1380 #endif
1381 #ifdef CONFIG_TRACE_IRQFLAGS
1382 	unsigned int irq_events;
1383 	unsigned long hardirq_enable_ip;
1384 	unsigned long hardirq_disable_ip;
1385 	unsigned int hardirq_enable_event;
1386 	unsigned int hardirq_disable_event;
1387 	int hardirqs_enabled;
1388 	int hardirq_context;
1389 	unsigned long softirq_disable_ip;
1390 	unsigned long softirq_enable_ip;
1391 	unsigned int softirq_disable_event;
1392 	unsigned int softirq_enable_event;
1393 	int softirqs_enabled;
1394 	int softirq_context;
1395 #endif
1396 #ifdef CONFIG_LOCKDEP
1397 # define MAX_LOCK_DEPTH 48UL
1398 	u64 curr_chain_key;
1399 	int lockdep_depth;
1400 	unsigned int lockdep_recursion;
1401 	struct held_lock held_locks[MAX_LOCK_DEPTH];
1402 	gfp_t lockdep_reclaim_gfp;
1403 #endif
1404 
1405 /* journalling filesystem info */
1406 	void *journal_info;
1407 
1408 /* stacked block device info */
1409 	struct bio_list *bio_list;
1410 
1411 /* VM state */
1412 	struct reclaim_state *reclaim_state;
1413 
1414 	struct backing_dev_info *backing_dev_info;
1415 
1416 	struct io_context *io_context;
1417 
1418 	unsigned long ptrace_message;
1419 	siginfo_t *last_siginfo; /* For ptrace use.  */
1420 	struct task_io_accounting ioac;
1421 #if defined(CONFIG_TASK_XACCT)
1422 	u64 acct_rss_mem1;	/* accumulated rss usage */
1423 	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1424 	cputime_t acct_timexpd;	/* stime + utime since last update */
1425 #endif
1426 #ifdef CONFIG_CPUSETS
1427 	nodemask_t mems_allowed;	/* Protected by alloc_lock */
1428 	int cpuset_mem_spread_rotor;
1429 #endif
1430 #ifdef CONFIG_CGROUPS
1431 	/* Control Group info protected by css_set_lock */
1432 	struct css_set *cgroups;
1433 	/* cg_list protected by css_set_lock and tsk->alloc_lock */
1434 	struct list_head cg_list;
1435 #endif
1436 #ifdef CONFIG_FUTEX
1437 	struct robust_list_head __user *robust_list;
1438 #ifdef CONFIG_COMPAT
1439 	struct compat_robust_list_head __user *compat_robust_list;
1440 #endif
1441 	struct list_head pi_state_list;
1442 	struct futex_pi_state *pi_state_cache;
1443 #endif
1444 #ifdef CONFIG_PERF_EVENTS
1445 	struct perf_event_context *perf_event_ctxp;
1446 	struct mutex perf_event_mutex;
1447 	struct list_head perf_event_list;
1448 #endif
1449 #ifdef CONFIG_NUMA
1450 	struct mempolicy *mempolicy;	/* Protected by alloc_lock */
1451 	short il_next;
1452 #endif
1453 	atomic_t fs_excl;	/* holding fs exclusive resources */
1454 	struct rcu_head rcu;
1455 
1456 	/*
1457 	 * cache last used pipe for splice
1458 	 */
1459 	struct pipe_inode_info *splice_pipe;
1460 #ifdef	CONFIG_TASK_DELAY_ACCT
1461 	struct task_delay_info *delays;
1462 #endif
1463 #ifdef CONFIG_FAULT_INJECTION
1464 	int make_it_fail;
1465 #endif
1466 	struct prop_local_single dirties;
1467 #ifdef CONFIG_LATENCYTOP
1468 	int latency_record_count;
1469 	struct latency_record latency_record[LT_SAVECOUNT];
1470 #endif
1471 	/*
1472 	 * time slack values; these are used to round up poll() and
1473 	 * select() etc timeout values. These are in nanoseconds.
1474 	 */
1475 	unsigned long timer_slack_ns;
1476 	unsigned long default_timer_slack_ns;
1477 
1478 	struct list_head	*scm_work_list;
1479 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1480 	/* Index of current stored address in ret_stack */
1481 	int curr_ret_stack;
1482 	/* Stack of return addresses for return function tracing */
1483 	struct ftrace_ret_stack	*ret_stack;
1484 	/* time stamp for last schedule */
1485 	unsigned long long ftrace_timestamp;
1486 	/*
1487 	 * Number of functions that haven't been traced
1488 	 * because of depth overrun.
1489 	 */
1490 	atomic_t trace_overrun;
1491 	/* Pause for the tracing */
1492 	atomic_t tracing_graph_pause;
1493 #endif
1494 #ifdef CONFIG_TRACING
1495 	/* state flags for use by tracers */
1496 	unsigned long trace;
1497 	/* bitmask of trace recursion */
1498 	unsigned long trace_recursion;
1499 #endif /* CONFIG_TRACING */
1500 	unsigned long stack_start;
1501 #ifdef CONFIG_CGROUP_MEM_RES_CTLR /* memcg uses this to do batch job */
1502 	struct memcg_batch_info {
1503 		int do_batch;	/* incremented when batch uncharge started */
1504 		struct mem_cgroup *memcg; /* target memcg of uncharge */
1505 		unsigned long bytes; 		/* uncharged usage */
1506 		unsigned long memsw_bytes; /* uncharged mem+swap usage */
1507 	} memcg_batch;
1508 #endif
1509 };
1510 
1511 /* Future-safe accessor for struct task_struct's cpus_allowed. */
1512 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1513 
1514 /*
1515  * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1516  * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1517  * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1518  * values are inverted: lower p->prio value means higher priority.
1519  *
1520  * The MAX_USER_RT_PRIO value allows the actual maximum
1521  * RT priority to be separate from the value exported to
1522  * user-space.  This allows kernel threads to set their
1523  * priority to a value higher than any user task. Note:
1524  * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1525  */
1526 
1527 #define MAX_USER_RT_PRIO	100
1528 #define MAX_RT_PRIO		MAX_USER_RT_PRIO
1529 
1530 #define MAX_PRIO		(MAX_RT_PRIO + 40)
1531 #define DEFAULT_PRIO		(MAX_RT_PRIO + 20)
1532 
1533 static inline int rt_prio(int prio)
1534 {
1535 	if (unlikely(prio < MAX_RT_PRIO))
1536 		return 1;
1537 	return 0;
1538 }
1539 
1540 static inline int rt_task(struct task_struct *p)
1541 {
1542 	return rt_prio(p->prio);
1543 }
1544 
1545 static inline struct pid *task_pid(struct task_struct *task)
1546 {
1547 	return task->pids[PIDTYPE_PID].pid;
1548 }
1549 
1550 static inline struct pid *task_tgid(struct task_struct *task)
1551 {
1552 	return task->group_leader->pids[PIDTYPE_PID].pid;
1553 }
1554 
1555 /*
1556  * Without tasklist or rcu lock it is not safe to dereference
1557  * the result of task_pgrp/task_session even if task == current,
1558  * we can race with another thread doing sys_setsid/sys_setpgid.
1559  */
1560 static inline struct pid *task_pgrp(struct task_struct *task)
1561 {
1562 	return task->group_leader->pids[PIDTYPE_PGID].pid;
1563 }
1564 
1565 static inline struct pid *task_session(struct task_struct *task)
1566 {
1567 	return task->group_leader->pids[PIDTYPE_SID].pid;
1568 }
1569 
1570 struct pid_namespace;
1571 
1572 /*
1573  * the helpers to get the task's different pids as they are seen
1574  * from various namespaces
1575  *
1576  * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1577  * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1578  *                     current.
1579  * task_xid_nr_ns()  : id seen from the ns specified;
1580  *
1581  * set_task_vxid()   : assigns a virtual id to a task;
1582  *
1583  * see also pid_nr() etc in include/linux/pid.h
1584  */
1585 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1586 			struct pid_namespace *ns);
1587 
1588 static inline pid_t task_pid_nr(struct task_struct *tsk)
1589 {
1590 	return tsk->pid;
1591 }
1592 
1593 static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1594 					struct pid_namespace *ns)
1595 {
1596 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1597 }
1598 
1599 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1600 {
1601 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1602 }
1603 
1604 
1605 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1606 {
1607 	return tsk->tgid;
1608 }
1609 
1610 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1611 
1612 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1613 {
1614 	return pid_vnr(task_tgid(tsk));
1615 }
1616 
1617 
1618 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1619 					struct pid_namespace *ns)
1620 {
1621 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1622 }
1623 
1624 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1625 {
1626 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1627 }
1628 
1629 
1630 static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1631 					struct pid_namespace *ns)
1632 {
1633 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1634 }
1635 
1636 static inline pid_t task_session_vnr(struct task_struct *tsk)
1637 {
1638 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1639 }
1640 
1641 /* obsolete, do not use */
1642 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1643 {
1644 	return task_pgrp_nr_ns(tsk, &init_pid_ns);
1645 }
1646 
1647 /**
1648  * pid_alive - check that a task structure is not stale
1649  * @p: Task structure to be checked.
1650  *
1651  * Test if a process is not yet dead (at most zombie state)
1652  * If pid_alive fails, then pointers within the task structure
1653  * can be stale and must not be dereferenced.
1654  */
1655 static inline int pid_alive(struct task_struct *p)
1656 {
1657 	return p->pids[PIDTYPE_PID].pid != NULL;
1658 }
1659 
1660 /**
1661  * is_global_init - check if a task structure is init
1662  * @tsk: Task structure to be checked.
1663  *
1664  * Check if a task structure is the first user space task the kernel created.
1665  */
1666 static inline int is_global_init(struct task_struct *tsk)
1667 {
1668 	return tsk->pid == 1;
1669 }
1670 
1671 /*
1672  * is_container_init:
1673  * check whether in the task is init in its own pid namespace.
1674  */
1675 extern int is_container_init(struct task_struct *tsk);
1676 
1677 extern struct pid *cad_pid;
1678 
1679 extern void free_task(struct task_struct *tsk);
1680 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1681 
1682 extern void __put_task_struct(struct task_struct *t);
1683 
1684 static inline void put_task_struct(struct task_struct *t)
1685 {
1686 	if (atomic_dec_and_test(&t->usage))
1687 		__put_task_struct(t);
1688 }
1689 
1690 extern void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1691 extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1692 
1693 /*
1694  * Per process flags
1695  */
1696 #define PF_ALIGNWARN	0x00000001	/* Print alignment warning msgs */
1697 					/* Not implemented yet, only for 486*/
1698 #define PF_STARTING	0x00000002	/* being created */
1699 #define PF_EXITING	0x00000004	/* getting shut down */
1700 #define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
1701 #define PF_VCPU		0x00000010	/* I'm a virtual CPU */
1702 #define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
1703 #define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
1704 #define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
1705 #define PF_DUMPCORE	0x00000200	/* dumped core */
1706 #define PF_SIGNALED	0x00000400	/* killed by a signal */
1707 #define PF_MEMALLOC	0x00000800	/* Allocating memory */
1708 #define PF_FLUSHER	0x00001000	/* responsible for disk writeback */
1709 #define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
1710 #define PF_FREEZING	0x00004000	/* freeze in progress. do not account to load */
1711 #define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
1712 #define PF_FROZEN	0x00010000	/* frozen for system suspend */
1713 #define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
1714 #define PF_KSWAPD	0x00040000	/* I am kswapd */
1715 #define PF_OOM_ORIGIN	0x00080000	/* Allocating much memory to others */
1716 #define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
1717 #define PF_KTHREAD	0x00200000	/* I am a kernel thread */
1718 #define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
1719 #define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
1720 #define PF_SPREAD_PAGE	0x01000000	/* Spread page cache over cpuset */
1721 #define PF_SPREAD_SLAB	0x02000000	/* Spread some slab caches over cpuset */
1722 #define PF_THREAD_BOUND	0x04000000	/* Thread bound to specific cpu */
1723 #define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
1724 #define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
1725 #define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
1726 #define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezeable */
1727 #define PF_FREEZER_NOSIG 0x80000000	/* Freezer won't send signals to it */
1728 
1729 /*
1730  * Only the _current_ task can read/write to tsk->flags, but other
1731  * tasks can access tsk->flags in readonly mode for example
1732  * with tsk_used_math (like during threaded core dumping).
1733  * There is however an exception to this rule during ptrace
1734  * or during fork: the ptracer task is allowed to write to the
1735  * child->flags of its traced child (same goes for fork, the parent
1736  * can write to the child->flags), because we're guaranteed the
1737  * child is not running and in turn not changing child->flags
1738  * at the same time the parent does it.
1739  */
1740 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1741 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1742 #define clear_used_math() clear_stopped_child_used_math(current)
1743 #define set_used_math() set_stopped_child_used_math(current)
1744 #define conditional_stopped_child_used_math(condition, child) \
1745 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1746 #define conditional_used_math(condition) \
1747 	conditional_stopped_child_used_math(condition, current)
1748 #define copy_to_stopped_child_used_math(child) \
1749 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1750 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1751 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1752 #define used_math() tsk_used_math(current)
1753 
1754 #ifdef CONFIG_TREE_PREEMPT_RCU
1755 
1756 #define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */
1757 #define RCU_READ_UNLOCK_NEED_QS (1 << 1) /* RCU core needs CPU response. */
1758 
1759 static inline void rcu_copy_process(struct task_struct *p)
1760 {
1761 	p->rcu_read_lock_nesting = 0;
1762 	p->rcu_read_unlock_special = 0;
1763 	p->rcu_blocked_node = NULL;
1764 	INIT_LIST_HEAD(&p->rcu_node_entry);
1765 }
1766 
1767 #else
1768 
1769 static inline void rcu_copy_process(struct task_struct *p)
1770 {
1771 }
1772 
1773 #endif
1774 
1775 #ifdef CONFIG_SMP
1776 extern int set_cpus_allowed_ptr(struct task_struct *p,
1777 				const struct cpumask *new_mask);
1778 #else
1779 static inline int set_cpus_allowed_ptr(struct task_struct *p,
1780 				       const struct cpumask *new_mask)
1781 {
1782 	if (!cpumask_test_cpu(0, new_mask))
1783 		return -EINVAL;
1784 	return 0;
1785 }
1786 #endif
1787 
1788 #ifndef CONFIG_CPUMASK_OFFSTACK
1789 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1790 {
1791 	return set_cpus_allowed_ptr(p, &new_mask);
1792 }
1793 #endif
1794 
1795 /*
1796  * Architectures can set this to 1 if they have specified
1797  * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
1798  * but then during bootup it turns out that sched_clock()
1799  * is reliable after all:
1800  */
1801 #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1802 extern int sched_clock_stable;
1803 #endif
1804 
1805 /* ftrace calls sched_clock() directly */
1806 extern unsigned long long notrace sched_clock(void);
1807 
1808 extern void sched_clock_init(void);
1809 extern u64 sched_clock_cpu(int cpu);
1810 
1811 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1812 static inline void sched_clock_tick(void)
1813 {
1814 }
1815 
1816 static inline void sched_clock_idle_sleep_event(void)
1817 {
1818 }
1819 
1820 static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
1821 {
1822 }
1823 #else
1824 extern void sched_clock_tick(void);
1825 extern void sched_clock_idle_sleep_event(void);
1826 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1827 #endif
1828 
1829 /*
1830  * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
1831  * clock constructed from sched_clock():
1832  */
1833 extern unsigned long long cpu_clock(int cpu);
1834 
1835 extern unsigned long long
1836 task_sched_runtime(struct task_struct *task);
1837 extern unsigned long long thread_group_sched_runtime(struct task_struct *task);
1838 
1839 /* sched_exec is called by processes performing an exec */
1840 #ifdef CONFIG_SMP
1841 extern void sched_exec(void);
1842 #else
1843 #define sched_exec()   {}
1844 #endif
1845 
1846 extern void sched_clock_idle_sleep_event(void);
1847 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1848 
1849 #ifdef CONFIG_HOTPLUG_CPU
1850 extern void idle_task_exit(void);
1851 #else
1852 static inline void idle_task_exit(void) {}
1853 #endif
1854 
1855 extern void sched_idle_next(void);
1856 
1857 #if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1858 extern void wake_up_idle_cpu(int cpu);
1859 #else
1860 static inline void wake_up_idle_cpu(int cpu) { }
1861 #endif
1862 
1863 extern unsigned int sysctl_sched_latency;
1864 extern unsigned int sysctl_sched_min_granularity;
1865 extern unsigned int sysctl_sched_wakeup_granularity;
1866 extern unsigned int sysctl_sched_shares_ratelimit;
1867 extern unsigned int sysctl_sched_shares_thresh;
1868 extern unsigned int sysctl_sched_child_runs_first;
1869 
1870 enum sched_tunable_scaling {
1871 	SCHED_TUNABLESCALING_NONE,
1872 	SCHED_TUNABLESCALING_LOG,
1873 	SCHED_TUNABLESCALING_LINEAR,
1874 	SCHED_TUNABLESCALING_END,
1875 };
1876 extern enum sched_tunable_scaling sysctl_sched_tunable_scaling;
1877 
1878 #ifdef CONFIG_SCHED_DEBUG
1879 extern unsigned int sysctl_sched_migration_cost;
1880 extern unsigned int sysctl_sched_nr_migrate;
1881 extern unsigned int sysctl_sched_time_avg;
1882 extern unsigned int sysctl_timer_migration;
1883 
1884 int sched_proc_update_handler(struct ctl_table *table, int write,
1885 		void __user *buffer, size_t *length,
1886 		loff_t *ppos);
1887 #endif
1888 #ifdef CONFIG_SCHED_DEBUG
1889 static inline unsigned int get_sysctl_timer_migration(void)
1890 {
1891 	return sysctl_timer_migration;
1892 }
1893 #else
1894 static inline unsigned int get_sysctl_timer_migration(void)
1895 {
1896 	return 1;
1897 }
1898 #endif
1899 extern unsigned int sysctl_sched_rt_period;
1900 extern int sysctl_sched_rt_runtime;
1901 
1902 int sched_rt_handler(struct ctl_table *table, int write,
1903 		void __user *buffer, size_t *lenp,
1904 		loff_t *ppos);
1905 
1906 extern unsigned int sysctl_sched_compat_yield;
1907 
1908 #ifdef CONFIG_RT_MUTEXES
1909 extern int rt_mutex_getprio(struct task_struct *p);
1910 extern void rt_mutex_setprio(struct task_struct *p, int prio);
1911 extern void rt_mutex_adjust_pi(struct task_struct *p);
1912 #else
1913 static inline int rt_mutex_getprio(struct task_struct *p)
1914 {
1915 	return p->normal_prio;
1916 }
1917 # define rt_mutex_adjust_pi(p)		do { } while (0)
1918 #endif
1919 
1920 extern void set_user_nice(struct task_struct *p, long nice);
1921 extern int task_prio(const struct task_struct *p);
1922 extern int task_nice(const struct task_struct *p);
1923 extern int can_nice(const struct task_struct *p, const int nice);
1924 extern int task_curr(const struct task_struct *p);
1925 extern int idle_cpu(int cpu);
1926 extern int sched_setscheduler(struct task_struct *, int, struct sched_param *);
1927 extern int sched_setscheduler_nocheck(struct task_struct *, int,
1928 				      struct sched_param *);
1929 extern struct task_struct *idle_task(int cpu);
1930 extern struct task_struct *curr_task(int cpu);
1931 extern void set_curr_task(int cpu, struct task_struct *p);
1932 
1933 void yield(void);
1934 
1935 /*
1936  * The default (Linux) execution domain.
1937  */
1938 extern struct exec_domain	default_exec_domain;
1939 
1940 union thread_union {
1941 	struct thread_info thread_info;
1942 	unsigned long stack[THREAD_SIZE/sizeof(long)];
1943 };
1944 
1945 #ifndef __HAVE_ARCH_KSTACK_END
1946 static inline int kstack_end(void *addr)
1947 {
1948 	/* Reliable end of stack detection:
1949 	 * Some APM bios versions misalign the stack
1950 	 */
1951 	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1952 }
1953 #endif
1954 
1955 extern union thread_union init_thread_union;
1956 extern struct task_struct init_task;
1957 
1958 extern struct   mm_struct init_mm;
1959 
1960 extern struct pid_namespace init_pid_ns;
1961 
1962 /*
1963  * find a task by one of its numerical ids
1964  *
1965  * find_task_by_pid_ns():
1966  *      finds a task by its pid in the specified namespace
1967  * find_task_by_vpid():
1968  *      finds a task by its virtual pid
1969  *
1970  * see also find_vpid() etc in include/linux/pid.h
1971  */
1972 
1973 extern struct task_struct *find_task_by_vpid(pid_t nr);
1974 extern struct task_struct *find_task_by_pid_ns(pid_t nr,
1975 		struct pid_namespace *ns);
1976 
1977 extern void __set_special_pids(struct pid *pid);
1978 
1979 /* per-UID process charging. */
1980 extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
1981 static inline struct user_struct *get_uid(struct user_struct *u)
1982 {
1983 	atomic_inc(&u->__count);
1984 	return u;
1985 }
1986 extern void free_uid(struct user_struct *);
1987 extern void release_uids(struct user_namespace *ns);
1988 
1989 #include <asm/current.h>
1990 
1991 extern void do_timer(unsigned long ticks);
1992 
1993 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
1994 extern int wake_up_process(struct task_struct *tsk);
1995 extern void wake_up_new_task(struct task_struct *tsk,
1996 				unsigned long clone_flags);
1997 #ifdef CONFIG_SMP
1998  extern void kick_process(struct task_struct *tsk);
1999 #else
2000  static inline void kick_process(struct task_struct *tsk) { }
2001 #endif
2002 extern void sched_fork(struct task_struct *p, int clone_flags);
2003 extern void sched_dead(struct task_struct *p);
2004 
2005 extern void proc_caches_init(void);
2006 extern void flush_signals(struct task_struct *);
2007 extern void __flush_signals(struct task_struct *);
2008 extern void ignore_signals(struct task_struct *);
2009 extern void flush_signal_handlers(struct task_struct *, int force_default);
2010 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2011 
2012 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
2013 {
2014 	unsigned long flags;
2015 	int ret;
2016 
2017 	spin_lock_irqsave(&tsk->sighand->siglock, flags);
2018 	ret = dequeue_signal(tsk, mask, info);
2019 	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
2020 
2021 	return ret;
2022 }
2023 
2024 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
2025 			      sigset_t *mask);
2026 extern void unblock_all_signals(void);
2027 extern void release_task(struct task_struct * p);
2028 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2029 extern int force_sigsegv(int, struct task_struct *);
2030 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2031 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2032 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2033 extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
2034 extern int kill_pgrp(struct pid *pid, int sig, int priv);
2035 extern int kill_pid(struct pid *pid, int sig, int priv);
2036 extern int kill_proc_info(int, struct siginfo *, pid_t);
2037 extern int do_notify_parent(struct task_struct *, int);
2038 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2039 extern void force_sig(int, struct task_struct *);
2040 extern int send_sig(int, struct task_struct *, int);
2041 extern void zap_other_threads(struct task_struct *p);
2042 extern struct sigqueue *sigqueue_alloc(void);
2043 extern void sigqueue_free(struct sigqueue *);
2044 extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
2045 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2046 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
2047 
2048 static inline int kill_cad_pid(int sig, int priv)
2049 {
2050 	return kill_pid(cad_pid, sig, priv);
2051 }
2052 
2053 /* These can be the second arg to send_sig_info/send_group_sig_info.  */
2054 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
2055 #define SEND_SIG_PRIV	((struct siginfo *) 1)
2056 #define SEND_SIG_FORCED	((struct siginfo *) 2)
2057 
2058 /*
2059  * True if we are on the alternate signal stack.
2060  */
2061 static inline int on_sig_stack(unsigned long sp)
2062 {
2063 #ifdef CONFIG_STACK_GROWSUP
2064 	return sp >= current->sas_ss_sp &&
2065 		sp - current->sas_ss_sp < current->sas_ss_size;
2066 #else
2067 	return sp > current->sas_ss_sp &&
2068 		sp - current->sas_ss_sp <= current->sas_ss_size;
2069 #endif
2070 }
2071 
2072 static inline int sas_ss_flags(unsigned long sp)
2073 {
2074 	return (current->sas_ss_size == 0 ? SS_DISABLE
2075 		: on_sig_stack(sp) ? SS_ONSTACK : 0);
2076 }
2077 
2078 /*
2079  * Routines for handling mm_structs
2080  */
2081 extern struct mm_struct * mm_alloc(void);
2082 
2083 /* mmdrop drops the mm and the page tables */
2084 extern void __mmdrop(struct mm_struct *);
2085 static inline void mmdrop(struct mm_struct * mm)
2086 {
2087 	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2088 		__mmdrop(mm);
2089 }
2090 
2091 /* mmput gets rid of the mappings and all user-space */
2092 extern void mmput(struct mm_struct *);
2093 /* Grab a reference to a task's mm, if it is not already going away */
2094 extern struct mm_struct *get_task_mm(struct task_struct *task);
2095 /* Remove the current tasks stale references to the old mm_struct */
2096 extern void mm_release(struct task_struct *, struct mm_struct *);
2097 /* Allocate a new mm structure and copy contents from tsk->mm */
2098 extern struct mm_struct *dup_mm(struct task_struct *tsk);
2099 
2100 extern int copy_thread(unsigned long, unsigned long, unsigned long,
2101 			struct task_struct *, struct pt_regs *);
2102 extern void flush_thread(void);
2103 extern void exit_thread(void);
2104 
2105 extern void exit_files(struct task_struct *);
2106 extern void __cleanup_signal(struct signal_struct *);
2107 extern void __cleanup_sighand(struct sighand_struct *);
2108 
2109 extern void exit_itimers(struct signal_struct *);
2110 extern void flush_itimer_signals(void);
2111 
2112 extern NORET_TYPE void do_group_exit(int);
2113 
2114 extern void daemonize(const char *, ...);
2115 extern int allow_signal(int);
2116 extern int disallow_signal(int);
2117 
2118 extern int do_execve(char *, char __user * __user *, char __user * __user *, struct pt_regs *);
2119 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
2120 struct task_struct *fork_idle(int);
2121 
2122 extern void set_task_comm(struct task_struct *tsk, char *from);
2123 extern char *get_task_comm(char *to, struct task_struct *tsk);
2124 
2125 #ifdef CONFIG_SMP
2126 extern void wait_task_context_switch(struct task_struct *p);
2127 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2128 #else
2129 static inline void wait_task_context_switch(struct task_struct *p) {}
2130 static inline unsigned long wait_task_inactive(struct task_struct *p,
2131 					       long match_state)
2132 {
2133 	return 1;
2134 }
2135 #endif
2136 
2137 #define next_task(p) \
2138 	list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2139 
2140 #define for_each_process(p) \
2141 	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2142 
2143 extern bool current_is_single_threaded(void);
2144 
2145 /*
2146  * Careful: do_each_thread/while_each_thread is a double loop so
2147  *          'break' will not work as expected - use goto instead.
2148  */
2149 #define do_each_thread(g, t) \
2150 	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2151 
2152 #define while_each_thread(g, t) \
2153 	while ((t = next_thread(t)) != g)
2154 
2155 /* de_thread depends on thread_group_leader not being a pid based check */
2156 #define thread_group_leader(p)	(p == p->group_leader)
2157 
2158 /* Do to the insanities of de_thread it is possible for a process
2159  * to have the pid of the thread group leader without actually being
2160  * the thread group leader.  For iteration through the pids in proc
2161  * all we care about is that we have a task with the appropriate
2162  * pid, we don't actually care if we have the right task.
2163  */
2164 static inline int has_group_leader_pid(struct task_struct *p)
2165 {
2166 	return p->pid == p->tgid;
2167 }
2168 
2169 static inline
2170 int same_thread_group(struct task_struct *p1, struct task_struct *p2)
2171 {
2172 	return p1->tgid == p2->tgid;
2173 }
2174 
2175 static inline struct task_struct *next_thread(const struct task_struct *p)
2176 {
2177 	return list_entry_rcu(p->thread_group.next,
2178 			      struct task_struct, thread_group);
2179 }
2180 
2181 static inline int thread_group_empty(struct task_struct *p)
2182 {
2183 	return list_empty(&p->thread_group);
2184 }
2185 
2186 #define delay_group_leader(p) \
2187 		(thread_group_leader(p) && !thread_group_empty(p))
2188 
2189 static inline int task_detached(struct task_struct *p)
2190 {
2191 	return p->exit_signal == -1;
2192 }
2193 
2194 /*
2195  * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2196  * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2197  * pins the final release of task.io_context.  Also protects ->cpuset and
2198  * ->cgroup.subsys[].
2199  *
2200  * Nests both inside and outside of read_lock(&tasklist_lock).
2201  * It must not be nested with write_lock_irq(&tasklist_lock),
2202  * neither inside nor outside.
2203  */
2204 static inline void task_lock(struct task_struct *p)
2205 {
2206 	spin_lock(&p->alloc_lock);
2207 }
2208 
2209 static inline void task_unlock(struct task_struct *p)
2210 {
2211 	spin_unlock(&p->alloc_lock);
2212 }
2213 
2214 extern struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2215 							unsigned long *flags);
2216 
2217 static inline void unlock_task_sighand(struct task_struct *tsk,
2218 						unsigned long *flags)
2219 {
2220 	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2221 }
2222 
2223 #ifndef __HAVE_THREAD_FUNCTIONS
2224 
2225 #define task_thread_info(task)	((struct thread_info *)(task)->stack)
2226 #define task_stack_page(task)	((task)->stack)
2227 
2228 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2229 {
2230 	*task_thread_info(p) = *task_thread_info(org);
2231 	task_thread_info(p)->task = p;
2232 }
2233 
2234 static inline unsigned long *end_of_stack(struct task_struct *p)
2235 {
2236 	return (unsigned long *)(task_thread_info(p) + 1);
2237 }
2238 
2239 #endif
2240 
2241 static inline int object_is_on_stack(void *obj)
2242 {
2243 	void *stack = task_stack_page(current);
2244 
2245 	return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2246 }
2247 
2248 extern void thread_info_cache_init(void);
2249 
2250 #ifdef CONFIG_DEBUG_STACK_USAGE
2251 static inline unsigned long stack_not_used(struct task_struct *p)
2252 {
2253 	unsigned long *n = end_of_stack(p);
2254 
2255 	do { 	/* Skip over canary */
2256 		n++;
2257 	} while (!*n);
2258 
2259 	return (unsigned long)n - (unsigned long)end_of_stack(p);
2260 }
2261 #endif
2262 
2263 /* set thread flags in other task's structures
2264  * - see asm/thread_info.h for TIF_xxxx flags available
2265  */
2266 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2267 {
2268 	set_ti_thread_flag(task_thread_info(tsk), flag);
2269 }
2270 
2271 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2272 {
2273 	clear_ti_thread_flag(task_thread_info(tsk), flag);
2274 }
2275 
2276 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2277 {
2278 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2279 }
2280 
2281 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2282 {
2283 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2284 }
2285 
2286 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2287 {
2288 	return test_ti_thread_flag(task_thread_info(tsk), flag);
2289 }
2290 
2291 static inline void set_tsk_need_resched(struct task_struct *tsk)
2292 {
2293 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2294 }
2295 
2296 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2297 {
2298 	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2299 }
2300 
2301 static inline int test_tsk_need_resched(struct task_struct *tsk)
2302 {
2303 	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2304 }
2305 
2306 static inline int restart_syscall(void)
2307 {
2308 	set_tsk_thread_flag(current, TIF_SIGPENDING);
2309 	return -ERESTARTNOINTR;
2310 }
2311 
2312 static inline int signal_pending(struct task_struct *p)
2313 {
2314 	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2315 }
2316 
2317 static inline int __fatal_signal_pending(struct task_struct *p)
2318 {
2319 	return unlikely(sigismember(&p->pending.signal, SIGKILL));
2320 }
2321 
2322 static inline int fatal_signal_pending(struct task_struct *p)
2323 {
2324 	return signal_pending(p) && __fatal_signal_pending(p);
2325 }
2326 
2327 static inline int signal_pending_state(long state, struct task_struct *p)
2328 {
2329 	if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2330 		return 0;
2331 	if (!signal_pending(p))
2332 		return 0;
2333 
2334 	return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2335 }
2336 
2337 static inline int need_resched(void)
2338 {
2339 	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
2340 }
2341 
2342 /*
2343  * cond_resched() and cond_resched_lock(): latency reduction via
2344  * explicit rescheduling in places that are safe. The return
2345  * value indicates whether a reschedule was done in fact.
2346  * cond_resched_lock() will drop the spinlock before scheduling,
2347  * cond_resched_softirq() will enable bhs before scheduling.
2348  */
2349 extern int _cond_resched(void);
2350 
2351 #define cond_resched() ({			\
2352 	__might_sleep(__FILE__, __LINE__, 0);	\
2353 	_cond_resched();			\
2354 })
2355 
2356 extern int __cond_resched_lock(spinlock_t *lock);
2357 
2358 #ifdef CONFIG_PREEMPT
2359 #define PREEMPT_LOCK_OFFSET	PREEMPT_OFFSET
2360 #else
2361 #define PREEMPT_LOCK_OFFSET	0
2362 #endif
2363 
2364 #define cond_resched_lock(lock) ({				\
2365 	__might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);	\
2366 	__cond_resched_lock(lock);				\
2367 })
2368 
2369 extern int __cond_resched_softirq(void);
2370 
2371 #define cond_resched_softirq() ({				\
2372 	__might_sleep(__FILE__, __LINE__, SOFTIRQ_OFFSET);	\
2373 	__cond_resched_softirq();				\
2374 })
2375 
2376 /*
2377  * Does a critical section need to be broken due to another
2378  * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2379  * but a general need for low latency)
2380  */
2381 static inline int spin_needbreak(spinlock_t *lock)
2382 {
2383 #ifdef CONFIG_PREEMPT
2384 	return spin_is_contended(lock);
2385 #else
2386 	return 0;
2387 #endif
2388 }
2389 
2390 /*
2391  * Thread group CPU time accounting.
2392  */
2393 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2394 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2395 
2396 static inline void thread_group_cputime_init(struct signal_struct *sig)
2397 {
2398 	spin_lock_init(&sig->cputimer.lock);
2399 }
2400 
2401 static inline void thread_group_cputime_free(struct signal_struct *sig)
2402 {
2403 }
2404 
2405 /*
2406  * Reevaluate whether the task has signals pending delivery.
2407  * Wake the task if so.
2408  * This is required every time the blocked sigset_t changes.
2409  * callers must hold sighand->siglock.
2410  */
2411 extern void recalc_sigpending_and_wake(struct task_struct *t);
2412 extern void recalc_sigpending(void);
2413 
2414 extern void signal_wake_up(struct task_struct *t, int resume_stopped);
2415 
2416 /*
2417  * Wrappers for p->thread_info->cpu access. No-op on UP.
2418  */
2419 #ifdef CONFIG_SMP
2420 
2421 static inline unsigned int task_cpu(const struct task_struct *p)
2422 {
2423 	return task_thread_info(p)->cpu;
2424 }
2425 
2426 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2427 
2428 #else
2429 
2430 static inline unsigned int task_cpu(const struct task_struct *p)
2431 {
2432 	return 0;
2433 }
2434 
2435 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2436 {
2437 }
2438 
2439 #endif /* CONFIG_SMP */
2440 
2441 #ifdef CONFIG_TRACING
2442 extern void
2443 __trace_special(void *__tr, void *__data,
2444 		unsigned long arg1, unsigned long arg2, unsigned long arg3);
2445 #else
2446 static inline void
2447 __trace_special(void *__tr, void *__data,
2448 		unsigned long arg1, unsigned long arg2, unsigned long arg3)
2449 {
2450 }
2451 #endif
2452 
2453 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2454 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2455 
2456 extern void normalize_rt_tasks(void);
2457 
2458 #ifdef CONFIG_CGROUP_SCHED
2459 
2460 extern struct task_group init_task_group;
2461 
2462 extern struct task_group *sched_create_group(struct task_group *parent);
2463 extern void sched_destroy_group(struct task_group *tg);
2464 extern void sched_move_task(struct task_struct *tsk);
2465 #ifdef CONFIG_FAIR_GROUP_SCHED
2466 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2467 extern unsigned long sched_group_shares(struct task_group *tg);
2468 #endif
2469 #ifdef CONFIG_RT_GROUP_SCHED
2470 extern int sched_group_set_rt_runtime(struct task_group *tg,
2471 				      long rt_runtime_us);
2472 extern long sched_group_rt_runtime(struct task_group *tg);
2473 extern int sched_group_set_rt_period(struct task_group *tg,
2474 				      long rt_period_us);
2475 extern long sched_group_rt_period(struct task_group *tg);
2476 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
2477 #endif
2478 #endif
2479 
2480 extern int task_can_switch_user(struct user_struct *up,
2481 					struct task_struct *tsk);
2482 
2483 #ifdef CONFIG_TASK_XACCT
2484 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2485 {
2486 	tsk->ioac.rchar += amt;
2487 }
2488 
2489 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2490 {
2491 	tsk->ioac.wchar += amt;
2492 }
2493 
2494 static inline void inc_syscr(struct task_struct *tsk)
2495 {
2496 	tsk->ioac.syscr++;
2497 }
2498 
2499 static inline void inc_syscw(struct task_struct *tsk)
2500 {
2501 	tsk->ioac.syscw++;
2502 }
2503 #else
2504 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2505 {
2506 }
2507 
2508 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2509 {
2510 }
2511 
2512 static inline void inc_syscr(struct task_struct *tsk)
2513 {
2514 }
2515 
2516 static inline void inc_syscw(struct task_struct *tsk)
2517 {
2518 }
2519 #endif
2520 
2521 #ifndef TASK_SIZE_OF
2522 #define TASK_SIZE_OF(tsk)	TASK_SIZE
2523 #endif
2524 
2525 /*
2526  * Call the function if the target task is executing on a CPU right now:
2527  */
2528 extern void task_oncpu_function_call(struct task_struct *p,
2529 				     void (*func) (void *info), void *info);
2530 
2531 
2532 #ifdef CONFIG_MM_OWNER
2533 extern void mm_update_next_owner(struct mm_struct *mm);
2534 extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2535 #else
2536 static inline void mm_update_next_owner(struct mm_struct *mm)
2537 {
2538 }
2539 
2540 static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2541 {
2542 }
2543 #endif /* CONFIG_MM_OWNER */
2544 
2545 static inline unsigned long task_rlimit(const struct task_struct *tsk,
2546 		unsigned int limit)
2547 {
2548 	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur);
2549 }
2550 
2551 static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
2552 		unsigned int limit)
2553 {
2554 	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max);
2555 }
2556 
2557 static inline unsigned long rlimit(unsigned int limit)
2558 {
2559 	return task_rlimit(current, limit);
2560 }
2561 
2562 static inline unsigned long rlimit_max(unsigned int limit)
2563 {
2564 	return task_rlimit_max(current, limit);
2565 }
2566 
2567 #endif /* __KERNEL__ */
2568 
2569 #endif
2570