xref: /linux-6.15/include/linux/sched.h (revision facb4edc)
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(unsigned long ticks);
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 void lockup_detector_init(void);
320 #else
321 static inline void touch_softlockup_watchdog(void)
322 {
323 }
324 static inline void touch_softlockup_watchdog_sync(void)
325 {
326 }
327 static inline void touch_all_softlockup_watchdogs(void)
328 {
329 }
330 static inline void lockup_detector_init(void)
331 {
332 }
333 #endif
334 
335 #ifdef CONFIG_DETECT_HUNG_TASK
336 extern unsigned int  sysctl_hung_task_panic;
337 extern unsigned long sysctl_hung_task_check_count;
338 extern unsigned long sysctl_hung_task_timeout_secs;
339 extern unsigned long sysctl_hung_task_warnings;
340 extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
341 					 void __user *buffer,
342 					 size_t *lenp, loff_t *ppos);
343 #else
344 /* Avoid need for ifdefs elsewhere in the code */
345 enum { sysctl_hung_task_timeout_secs = 0 };
346 #endif
347 
348 /* Attach to any functions which should be ignored in wchan output. */
349 #define __sched		__attribute__((__section__(".sched.text")))
350 
351 /* Linker adds these: start and end of __sched functions */
352 extern char __sched_text_start[], __sched_text_end[];
353 
354 /* Is this address in the __sched functions? */
355 extern int in_sched_functions(unsigned long addr);
356 
357 #define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
358 extern signed long schedule_timeout(signed long timeout);
359 extern signed long schedule_timeout_interruptible(signed long timeout);
360 extern signed long schedule_timeout_killable(signed long timeout);
361 extern signed long schedule_timeout_uninterruptible(signed long timeout);
362 asmlinkage void schedule(void);
363 extern int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner);
364 
365 struct nsproxy;
366 struct user_namespace;
367 
368 /*
369  * Default maximum number of active map areas, this limits the number of vmas
370  * per mm struct. Users can overwrite this number by sysctl but there is a
371  * problem.
372  *
373  * When a program's coredump is generated as ELF format, a section is created
374  * per a vma. In ELF, the number of sections is represented in unsigned short.
375  * This means the number of sections should be smaller than 65535 at coredump.
376  * Because the kernel adds some informative sections to a image of program at
377  * generating coredump, we need some margin. The number of extra sections is
378  * 1-3 now and depends on arch. We use "5" as safe margin, here.
379  */
380 #define MAPCOUNT_ELF_CORE_MARGIN	(5)
381 #define DEFAULT_MAX_MAP_COUNT	(USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)
382 
383 extern int sysctl_max_map_count;
384 
385 #include <linux/aio.h>
386 
387 #ifdef CONFIG_MMU
388 extern void arch_pick_mmap_layout(struct mm_struct *mm);
389 extern unsigned long
390 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
391 		       unsigned long, unsigned long);
392 extern unsigned long
393 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
394 			  unsigned long len, unsigned long pgoff,
395 			  unsigned long flags);
396 extern void arch_unmap_area(struct mm_struct *, unsigned long);
397 extern void arch_unmap_area_topdown(struct mm_struct *, unsigned long);
398 #else
399 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
400 #endif
401 
402 
403 extern void set_dumpable(struct mm_struct *mm, int value);
404 extern int get_dumpable(struct mm_struct *mm);
405 
406 /* mm flags */
407 /* dumpable bits */
408 #define MMF_DUMPABLE      0  /* core dump is permitted */
409 #define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
410 
411 #define MMF_DUMPABLE_BITS 2
412 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
413 
414 /* coredump filter bits */
415 #define MMF_DUMP_ANON_PRIVATE	2
416 #define MMF_DUMP_ANON_SHARED	3
417 #define MMF_DUMP_MAPPED_PRIVATE	4
418 #define MMF_DUMP_MAPPED_SHARED	5
419 #define MMF_DUMP_ELF_HEADERS	6
420 #define MMF_DUMP_HUGETLB_PRIVATE 7
421 #define MMF_DUMP_HUGETLB_SHARED  8
422 
423 #define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
424 #define MMF_DUMP_FILTER_BITS	7
425 #define MMF_DUMP_FILTER_MASK \
426 	(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
427 #define MMF_DUMP_FILTER_DEFAULT \
428 	((1 << MMF_DUMP_ANON_PRIVATE) |	(1 << MMF_DUMP_ANON_SHARED) |\
429 	 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
430 
431 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
432 # define MMF_DUMP_MASK_DEFAULT_ELF	(1 << MMF_DUMP_ELF_HEADERS)
433 #else
434 # define MMF_DUMP_MASK_DEFAULT_ELF	0
435 #endif
436 					/* leave room for more dump flags */
437 #define MMF_VM_MERGEABLE	16	/* KSM may merge identical pages */
438 
439 #define MMF_INIT_MASK		(MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
440 
441 struct sighand_struct {
442 	atomic_t		count;
443 	struct k_sigaction	action[_NSIG];
444 	spinlock_t		siglock;
445 	wait_queue_head_t	signalfd_wqh;
446 };
447 
448 struct pacct_struct {
449 	int			ac_flag;
450 	long			ac_exitcode;
451 	unsigned long		ac_mem;
452 	cputime_t		ac_utime, ac_stime;
453 	unsigned long		ac_minflt, ac_majflt;
454 };
455 
456 struct cpu_itimer {
457 	cputime_t expires;
458 	cputime_t incr;
459 	u32 error;
460 	u32 incr_error;
461 };
462 
463 /**
464  * struct task_cputime - collected CPU time counts
465  * @utime:		time spent in user mode, in &cputime_t units
466  * @stime:		time spent in kernel mode, in &cputime_t units
467  * @sum_exec_runtime:	total time spent on the CPU, in nanoseconds
468  *
469  * This structure groups together three kinds of CPU time that are
470  * tracked for threads and thread groups.  Most things considering
471  * CPU time want to group these counts together and treat all three
472  * of them in parallel.
473  */
474 struct task_cputime {
475 	cputime_t utime;
476 	cputime_t stime;
477 	unsigned long long sum_exec_runtime;
478 };
479 /* Alternate field names when used to cache expirations. */
480 #define prof_exp	stime
481 #define virt_exp	utime
482 #define sched_exp	sum_exec_runtime
483 
484 #define INIT_CPUTIME	\
485 	(struct task_cputime) {					\
486 		.utime = cputime_zero,				\
487 		.stime = cputime_zero,				\
488 		.sum_exec_runtime = 0,				\
489 	}
490 
491 /*
492  * Disable preemption until the scheduler is running.
493  * Reset by start_kernel()->sched_init()->init_idle().
494  *
495  * We include PREEMPT_ACTIVE to avoid cond_resched() from working
496  * before the scheduler is active -- see should_resched().
497  */
498 #define INIT_PREEMPT_COUNT	(1 + PREEMPT_ACTIVE)
499 
500 /**
501  * struct thread_group_cputimer - thread group interval timer counts
502  * @cputime:		thread group interval timers.
503  * @running:		non-zero when there are timers running and
504  * 			@cputime receives updates.
505  * @lock:		lock for fields in this struct.
506  *
507  * This structure contains the version of task_cputime, above, that is
508  * used for thread group CPU timer calculations.
509  */
510 struct thread_group_cputimer {
511 	struct task_cputime cputime;
512 	int running;
513 	spinlock_t lock;
514 };
515 
516 struct autogroup;
517 
518 /*
519  * NOTE! "signal_struct" does not have it's own
520  * locking, because a shared signal_struct always
521  * implies a shared sighand_struct, so locking
522  * sighand_struct is always a proper superset of
523  * the locking of signal_struct.
524  */
525 struct signal_struct {
526 	atomic_t		sigcnt;
527 	atomic_t		live;
528 	int			nr_threads;
529 
530 	wait_queue_head_t	wait_chldexit;	/* for wait4() */
531 
532 	/* current thread group signal load-balancing target: */
533 	struct task_struct	*curr_target;
534 
535 	/* shared signal handling: */
536 	struct sigpending	shared_pending;
537 
538 	/* thread group exit support */
539 	int			group_exit_code;
540 	/* overloaded:
541 	 * - notify group_exit_task when ->count is equal to notify_count
542 	 * - everyone except group_exit_task is stopped during signal delivery
543 	 *   of fatal signals, group_exit_task processes the signal.
544 	 */
545 	int			notify_count;
546 	struct task_struct	*group_exit_task;
547 
548 	/* thread group stop support, overloads group_exit_code too */
549 	int			group_stop_count;
550 	unsigned int		flags; /* see SIGNAL_* flags below */
551 
552 	/* POSIX.1b Interval Timers */
553 	struct list_head posix_timers;
554 
555 	/* ITIMER_REAL timer for the process */
556 	struct hrtimer real_timer;
557 	struct pid *leader_pid;
558 	ktime_t it_real_incr;
559 
560 	/*
561 	 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
562 	 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
563 	 * values are defined to 0 and 1 respectively
564 	 */
565 	struct cpu_itimer it[2];
566 
567 	/*
568 	 * Thread group totals for process CPU timers.
569 	 * See thread_group_cputimer(), et al, for details.
570 	 */
571 	struct thread_group_cputimer cputimer;
572 
573 	/* Earliest-expiration cache. */
574 	struct task_cputime cputime_expires;
575 
576 	struct list_head cpu_timers[3];
577 
578 	struct pid *tty_old_pgrp;
579 
580 	/* boolean value for session group leader */
581 	int leader;
582 
583 	struct tty_struct *tty; /* NULL if no tty */
584 
585 #ifdef CONFIG_SCHED_AUTOGROUP
586 	struct autogroup *autogroup;
587 #endif
588 	/*
589 	 * Cumulative resource counters for dead threads in the group,
590 	 * and for reaped dead child processes forked by this group.
591 	 * Live threads maintain their own counters and add to these
592 	 * in __exit_signal, except for the group leader.
593 	 */
594 	cputime_t utime, stime, cutime, cstime;
595 	cputime_t gtime;
596 	cputime_t cgtime;
597 #ifndef CONFIG_VIRT_CPU_ACCOUNTING
598 	cputime_t prev_utime, prev_stime;
599 #endif
600 	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
601 	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
602 	unsigned long inblock, oublock, cinblock, coublock;
603 	unsigned long maxrss, cmaxrss;
604 	struct task_io_accounting ioac;
605 
606 	/*
607 	 * Cumulative ns of schedule CPU time fo dead threads in the
608 	 * group, not including a zombie group leader, (This only differs
609 	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
610 	 * other than jiffies.)
611 	 */
612 	unsigned long long sum_sched_runtime;
613 
614 	/*
615 	 * We don't bother to synchronize most readers of this at all,
616 	 * because there is no reader checking a limit that actually needs
617 	 * to get both rlim_cur and rlim_max atomically, and either one
618 	 * alone is a single word that can safely be read normally.
619 	 * getrlimit/setrlimit use task_lock(current->group_leader) to
620 	 * protect this instead of the siglock, because they really
621 	 * have no need to disable irqs.
622 	 */
623 	struct rlimit rlim[RLIM_NLIMITS];
624 
625 #ifdef CONFIG_BSD_PROCESS_ACCT
626 	struct pacct_struct pacct;	/* per-process accounting information */
627 #endif
628 #ifdef CONFIG_TASKSTATS
629 	struct taskstats *stats;
630 #endif
631 #ifdef CONFIG_AUDIT
632 	unsigned audit_tty;
633 	struct tty_audit_buf *tty_audit_buf;
634 #endif
635 
636 	int oom_adj;		/* OOM kill score adjustment (bit shift) */
637 	int oom_score_adj;	/* OOM kill score adjustment */
638 
639 	struct mutex cred_guard_mutex;	/* guard against foreign influences on
640 					 * credential calculations
641 					 * (notably. ptrace) */
642 };
643 
644 /* Context switch must be unlocked if interrupts are to be enabled */
645 #ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
646 # define __ARCH_WANT_UNLOCKED_CTXSW
647 #endif
648 
649 /*
650  * Bits in flags field of signal_struct.
651  */
652 #define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
653 #define SIGNAL_STOP_DEQUEUED	0x00000002 /* stop signal dequeued */
654 #define SIGNAL_STOP_CONTINUED	0x00000004 /* SIGCONT since WCONTINUED reap */
655 #define SIGNAL_GROUP_EXIT	0x00000008 /* group exit in progress */
656 /*
657  * Pending notifications to parent.
658  */
659 #define SIGNAL_CLD_STOPPED	0x00000010
660 #define SIGNAL_CLD_CONTINUED	0x00000020
661 #define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
662 
663 #define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */
664 
665 /* If true, all threads except ->group_exit_task have pending SIGKILL */
666 static inline int signal_group_exit(const struct signal_struct *sig)
667 {
668 	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
669 		(sig->group_exit_task != NULL);
670 }
671 
672 /*
673  * Some day this will be a full-fledged user tracking system..
674  */
675 struct user_struct {
676 	atomic_t __count;	/* reference count */
677 	atomic_t processes;	/* How many processes does this user have? */
678 	atomic_t files;		/* How many open files does this user have? */
679 	atomic_t sigpending;	/* How many pending signals does this user have? */
680 #ifdef CONFIG_INOTIFY_USER
681 	atomic_t inotify_watches; /* How many inotify watches does this user have? */
682 	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
683 #endif
684 #ifdef CONFIG_FANOTIFY
685 	atomic_t fanotify_listeners;
686 #endif
687 #ifdef CONFIG_EPOLL
688 	atomic_t epoll_watches;	/* The number of file descriptors currently watched */
689 #endif
690 #ifdef CONFIG_POSIX_MQUEUE
691 	/* protected by mq_lock	*/
692 	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
693 #endif
694 	unsigned long locked_shm; /* How many pages of mlocked shm ? */
695 
696 #ifdef CONFIG_KEYS
697 	struct key *uid_keyring;	/* UID specific keyring */
698 	struct key *session_keyring;	/* UID's default session keyring */
699 #endif
700 
701 	/* Hash table maintenance information */
702 	struct hlist_node uidhash_node;
703 	uid_t uid;
704 	struct user_namespace *user_ns;
705 
706 #ifdef CONFIG_PERF_EVENTS
707 	atomic_long_t locked_vm;
708 #endif
709 };
710 
711 extern int uids_sysfs_init(void);
712 
713 extern struct user_struct *find_user(uid_t);
714 
715 extern struct user_struct root_user;
716 #define INIT_USER (&root_user)
717 
718 
719 struct backing_dev_info;
720 struct reclaim_state;
721 
722 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
723 struct sched_info {
724 	/* cumulative counters */
725 	unsigned long pcount;	      /* # of times run on this cpu */
726 	unsigned long long run_delay; /* time spent waiting on a runqueue */
727 
728 	/* timestamps */
729 	unsigned long long last_arrival,/* when we last ran on a cpu */
730 			   last_queued;	/* when we were last queued to run */
731 #ifdef CONFIG_SCHEDSTATS
732 	/* BKL stats */
733 	unsigned int bkl_count;
734 #endif
735 };
736 #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
737 
738 #ifdef CONFIG_TASK_DELAY_ACCT
739 struct task_delay_info {
740 	spinlock_t	lock;
741 	unsigned int	flags;	/* Private per-task flags */
742 
743 	/* For each stat XXX, add following, aligned appropriately
744 	 *
745 	 * struct timespec XXX_start, XXX_end;
746 	 * u64 XXX_delay;
747 	 * u32 XXX_count;
748 	 *
749 	 * Atomicity of updates to XXX_delay, XXX_count protected by
750 	 * single lock above (split into XXX_lock if contention is an issue).
751 	 */
752 
753 	/*
754 	 * XXX_count is incremented on every XXX operation, the delay
755 	 * associated with the operation is added to XXX_delay.
756 	 * XXX_delay contains the accumulated delay time in nanoseconds.
757 	 */
758 	struct timespec blkio_start, blkio_end;	/* Shared by blkio, swapin */
759 	u64 blkio_delay;	/* wait for sync block io completion */
760 	u64 swapin_delay;	/* wait for swapin block io completion */
761 	u32 blkio_count;	/* total count of the number of sync block */
762 				/* io operations performed */
763 	u32 swapin_count;	/* total count of the number of swapin block */
764 				/* io operations performed */
765 
766 	struct timespec freepages_start, freepages_end;
767 	u64 freepages_delay;	/* wait for memory reclaim */
768 	u32 freepages_count;	/* total count of memory reclaim */
769 };
770 #endif	/* CONFIG_TASK_DELAY_ACCT */
771 
772 static inline int sched_info_on(void)
773 {
774 #ifdef CONFIG_SCHEDSTATS
775 	return 1;
776 #elif defined(CONFIG_TASK_DELAY_ACCT)
777 	extern int delayacct_on;
778 	return delayacct_on;
779 #else
780 	return 0;
781 #endif
782 }
783 
784 enum cpu_idle_type {
785 	CPU_IDLE,
786 	CPU_NOT_IDLE,
787 	CPU_NEWLY_IDLE,
788 	CPU_MAX_IDLE_TYPES
789 };
790 
791 /*
792  * sched-domains (multiprocessor balancing) declarations:
793  */
794 
795 /*
796  * Increase resolution of nice-level calculations:
797  */
798 #define SCHED_LOAD_SHIFT	10
799 #define SCHED_LOAD_SCALE	(1L << SCHED_LOAD_SHIFT)
800 
801 #define SCHED_LOAD_SCALE_FUZZ	SCHED_LOAD_SCALE
802 
803 #ifdef CONFIG_SMP
804 #define SD_LOAD_BALANCE		0x0001	/* Do load balancing on this domain. */
805 #define SD_BALANCE_NEWIDLE	0x0002	/* Balance when about to become idle */
806 #define SD_BALANCE_EXEC		0x0004	/* Balance on exec */
807 #define SD_BALANCE_FORK		0x0008	/* Balance on fork, clone */
808 #define SD_BALANCE_WAKE		0x0010  /* Balance on wakeup */
809 #define SD_WAKE_AFFINE		0x0020	/* Wake task to waking CPU */
810 #define SD_PREFER_LOCAL		0x0040  /* Prefer to keep tasks local to this domain */
811 #define SD_SHARE_CPUPOWER	0x0080	/* Domain members share cpu power */
812 #define SD_POWERSAVINGS_BALANCE	0x0100	/* Balance for power savings */
813 #define SD_SHARE_PKG_RESOURCES	0x0200	/* Domain members share cpu pkg resources */
814 #define SD_SERIALIZE		0x0400	/* Only a single load balancing instance */
815 #define SD_ASYM_PACKING		0x0800  /* Place busy groups earlier in the domain */
816 #define SD_PREFER_SIBLING	0x1000	/* Prefer to place tasks in a sibling domain */
817 
818 enum powersavings_balance_level {
819 	POWERSAVINGS_BALANCE_NONE = 0,  /* No power saving load balance */
820 	POWERSAVINGS_BALANCE_BASIC,	/* Fill one thread/core/package
821 					 * first for long running threads
822 					 */
823 	POWERSAVINGS_BALANCE_WAKEUP,	/* Also bias task wakeups to semi-idle
824 					 * cpu package for power savings
825 					 */
826 	MAX_POWERSAVINGS_BALANCE_LEVELS
827 };
828 
829 extern int sched_mc_power_savings, sched_smt_power_savings;
830 
831 static inline int sd_balance_for_mc_power(void)
832 {
833 	if (sched_smt_power_savings)
834 		return SD_POWERSAVINGS_BALANCE;
835 
836 	if (!sched_mc_power_savings)
837 		return SD_PREFER_SIBLING;
838 
839 	return 0;
840 }
841 
842 static inline int sd_balance_for_package_power(void)
843 {
844 	if (sched_mc_power_savings | sched_smt_power_savings)
845 		return SD_POWERSAVINGS_BALANCE;
846 
847 	return SD_PREFER_SIBLING;
848 }
849 
850 extern int __weak arch_sd_sibiling_asym_packing(void);
851 
852 /*
853  * Optimise SD flags for power savings:
854  * SD_BALANCE_NEWIDLE helps agressive task consolidation and power savings.
855  * Keep default SD flags if sched_{smt,mc}_power_saving=0
856  */
857 
858 static inline int sd_power_saving_flags(void)
859 {
860 	if (sched_mc_power_savings | sched_smt_power_savings)
861 		return SD_BALANCE_NEWIDLE;
862 
863 	return 0;
864 }
865 
866 struct sched_group {
867 	struct sched_group *next;	/* Must be a circular list */
868 
869 	/*
870 	 * CPU power of this group, SCHED_LOAD_SCALE being max power for a
871 	 * single CPU.
872 	 */
873 	unsigned int cpu_power, cpu_power_orig;
874 	unsigned int group_weight;
875 
876 	/*
877 	 * The CPUs this group covers.
878 	 *
879 	 * NOTE: this field is variable length. (Allocated dynamically
880 	 * by attaching extra space to the end of the structure,
881 	 * depending on how many CPUs the kernel has booted up with)
882 	 *
883 	 * It is also be embedded into static data structures at build
884 	 * time. (See 'struct static_sched_group' in kernel/sched.c)
885 	 */
886 	unsigned long cpumask[0];
887 };
888 
889 static inline struct cpumask *sched_group_cpus(struct sched_group *sg)
890 {
891 	return to_cpumask(sg->cpumask);
892 }
893 
894 enum sched_domain_level {
895 	SD_LV_NONE = 0,
896 	SD_LV_SIBLING,
897 	SD_LV_MC,
898 	SD_LV_BOOK,
899 	SD_LV_CPU,
900 	SD_LV_NODE,
901 	SD_LV_ALLNODES,
902 	SD_LV_MAX
903 };
904 
905 struct sched_domain_attr {
906 	int relax_domain_level;
907 };
908 
909 #define SD_ATTR_INIT	(struct sched_domain_attr) {	\
910 	.relax_domain_level = -1,			\
911 }
912 
913 struct sched_domain {
914 	/* These fields must be setup */
915 	struct sched_domain *parent;	/* top domain must be null terminated */
916 	struct sched_domain *child;	/* bottom domain must be null terminated */
917 	struct sched_group *groups;	/* the balancing groups of the domain */
918 	unsigned long min_interval;	/* Minimum balance interval ms */
919 	unsigned long max_interval;	/* Maximum balance interval ms */
920 	unsigned int busy_factor;	/* less balancing by factor if busy */
921 	unsigned int imbalance_pct;	/* No balance until over watermark */
922 	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
923 	unsigned int busy_idx;
924 	unsigned int idle_idx;
925 	unsigned int newidle_idx;
926 	unsigned int wake_idx;
927 	unsigned int forkexec_idx;
928 	unsigned int smt_gain;
929 	int flags;			/* See SD_* */
930 	enum sched_domain_level level;
931 
932 	/* Runtime fields. */
933 	unsigned long last_balance;	/* init to jiffies. units in jiffies */
934 	unsigned int balance_interval;	/* initialise to 1. units in ms. */
935 	unsigned int nr_balance_failed; /* initialise to 0 */
936 
937 	u64 last_update;
938 
939 #ifdef CONFIG_SCHEDSTATS
940 	/* load_balance() stats */
941 	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
942 	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
943 	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
944 	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
945 	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
946 	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
947 	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
948 	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
949 
950 	/* Active load balancing */
951 	unsigned int alb_count;
952 	unsigned int alb_failed;
953 	unsigned int alb_pushed;
954 
955 	/* SD_BALANCE_EXEC stats */
956 	unsigned int sbe_count;
957 	unsigned int sbe_balanced;
958 	unsigned int sbe_pushed;
959 
960 	/* SD_BALANCE_FORK stats */
961 	unsigned int sbf_count;
962 	unsigned int sbf_balanced;
963 	unsigned int sbf_pushed;
964 
965 	/* try_to_wake_up() stats */
966 	unsigned int ttwu_wake_remote;
967 	unsigned int ttwu_move_affine;
968 	unsigned int ttwu_move_balance;
969 #endif
970 #ifdef CONFIG_SCHED_DEBUG
971 	char *name;
972 #endif
973 
974 	unsigned int span_weight;
975 	/*
976 	 * Span of all CPUs in this domain.
977 	 *
978 	 * NOTE: this field is variable length. (Allocated dynamically
979 	 * by attaching extra space to the end of the structure,
980 	 * depending on how many CPUs the kernel has booted up with)
981 	 *
982 	 * It is also be embedded into static data structures at build
983 	 * time. (See 'struct static_sched_domain' in kernel/sched.c)
984 	 */
985 	unsigned long span[0];
986 };
987 
988 static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
989 {
990 	return to_cpumask(sd->span);
991 }
992 
993 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
994 				    struct sched_domain_attr *dattr_new);
995 
996 /* Allocate an array of sched domains, for partition_sched_domains(). */
997 cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
998 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
999 
1000 /* Test a flag in parent sched domain */
1001 static inline int test_sd_parent(struct sched_domain *sd, int flag)
1002 {
1003 	if (sd->parent && (sd->parent->flags & flag))
1004 		return 1;
1005 
1006 	return 0;
1007 }
1008 
1009 unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu);
1010 unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu);
1011 
1012 #else /* CONFIG_SMP */
1013 
1014 struct sched_domain_attr;
1015 
1016 static inline void
1017 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1018 			struct sched_domain_attr *dattr_new)
1019 {
1020 }
1021 #endif	/* !CONFIG_SMP */
1022 
1023 
1024 struct io_context;			/* See blkdev.h */
1025 
1026 
1027 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1028 extern void prefetch_stack(struct task_struct *t);
1029 #else
1030 static inline void prefetch_stack(struct task_struct *t) { }
1031 #endif
1032 
1033 struct audit_context;		/* See audit.c */
1034 struct mempolicy;
1035 struct pipe_inode_info;
1036 struct uts_namespace;
1037 
1038 struct rq;
1039 struct sched_domain;
1040 
1041 /*
1042  * wake flags
1043  */
1044 #define WF_SYNC		0x01		/* waker goes to sleep after wakup */
1045 #define WF_FORK		0x02		/* child wakeup after fork */
1046 
1047 #define ENQUEUE_WAKEUP		1
1048 #define ENQUEUE_WAKING		2
1049 #define ENQUEUE_HEAD		4
1050 
1051 #define DEQUEUE_SLEEP		1
1052 
1053 struct sched_class {
1054 	const struct sched_class *next;
1055 
1056 	void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1057 	void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1058 	void (*yield_task) (struct rq *rq);
1059 
1060 	void (*check_preempt_curr) (struct rq *rq, struct task_struct *p, int flags);
1061 
1062 	struct task_struct * (*pick_next_task) (struct rq *rq);
1063 	void (*put_prev_task) (struct rq *rq, struct task_struct *p);
1064 
1065 #ifdef CONFIG_SMP
1066 	int  (*select_task_rq)(struct rq *rq, struct task_struct *p,
1067 			       int sd_flag, int flags);
1068 
1069 	void (*pre_schedule) (struct rq *this_rq, struct task_struct *task);
1070 	void (*post_schedule) (struct rq *this_rq);
1071 	void (*task_waking) (struct rq *this_rq, struct task_struct *task);
1072 	void (*task_woken) (struct rq *this_rq, struct task_struct *task);
1073 
1074 	void (*set_cpus_allowed)(struct task_struct *p,
1075 				 const struct cpumask *newmask);
1076 
1077 	void (*rq_online)(struct rq *rq);
1078 	void (*rq_offline)(struct rq *rq);
1079 #endif
1080 
1081 	void (*set_curr_task) (struct rq *rq);
1082 	void (*task_tick) (struct rq *rq, struct task_struct *p, int queued);
1083 	void (*task_fork) (struct task_struct *p);
1084 
1085 	void (*switched_from) (struct rq *this_rq, struct task_struct *task,
1086 			       int running);
1087 	void (*switched_to) (struct rq *this_rq, struct task_struct *task,
1088 			     int running);
1089 	void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1090 			     int oldprio, int running);
1091 
1092 	unsigned int (*get_rr_interval) (struct rq *rq,
1093 					 struct task_struct *task);
1094 
1095 #ifdef CONFIG_FAIR_GROUP_SCHED
1096 	void (*task_move_group) (struct task_struct *p, int on_rq);
1097 #endif
1098 };
1099 
1100 struct load_weight {
1101 	unsigned long weight, inv_weight;
1102 };
1103 
1104 #ifdef CONFIG_SCHEDSTATS
1105 struct sched_statistics {
1106 	u64			wait_start;
1107 	u64			wait_max;
1108 	u64			wait_count;
1109 	u64			wait_sum;
1110 	u64			iowait_count;
1111 	u64			iowait_sum;
1112 
1113 	u64			sleep_start;
1114 	u64			sleep_max;
1115 	s64			sum_sleep_runtime;
1116 
1117 	u64			block_start;
1118 	u64			block_max;
1119 	u64			exec_max;
1120 	u64			slice_max;
1121 
1122 	u64			nr_migrations_cold;
1123 	u64			nr_failed_migrations_affine;
1124 	u64			nr_failed_migrations_running;
1125 	u64			nr_failed_migrations_hot;
1126 	u64			nr_forced_migrations;
1127 
1128 	u64			nr_wakeups;
1129 	u64			nr_wakeups_sync;
1130 	u64			nr_wakeups_migrate;
1131 	u64			nr_wakeups_local;
1132 	u64			nr_wakeups_remote;
1133 	u64			nr_wakeups_affine;
1134 	u64			nr_wakeups_affine_attempts;
1135 	u64			nr_wakeups_passive;
1136 	u64			nr_wakeups_idle;
1137 };
1138 #endif
1139 
1140 struct sched_entity {
1141 	struct load_weight	load;		/* for load-balancing */
1142 	struct rb_node		run_node;
1143 	struct list_head	group_node;
1144 	unsigned int		on_rq;
1145 
1146 	u64			exec_start;
1147 	u64			sum_exec_runtime;
1148 	u64			vruntime;
1149 	u64			prev_sum_exec_runtime;
1150 
1151 	u64			nr_migrations;
1152 
1153 #ifdef CONFIG_SCHEDSTATS
1154 	struct sched_statistics statistics;
1155 #endif
1156 
1157 #ifdef CONFIG_FAIR_GROUP_SCHED
1158 	struct sched_entity	*parent;
1159 	/* rq on which this entity is (to be) queued: */
1160 	struct cfs_rq		*cfs_rq;
1161 	/* rq "owned" by this entity/group: */
1162 	struct cfs_rq		*my_q;
1163 #endif
1164 };
1165 
1166 struct sched_rt_entity {
1167 	struct list_head run_list;
1168 	unsigned long timeout;
1169 	unsigned int time_slice;
1170 	int nr_cpus_allowed;
1171 
1172 	struct sched_rt_entity *back;
1173 #ifdef CONFIG_RT_GROUP_SCHED
1174 	struct sched_rt_entity	*parent;
1175 	/* rq on which this entity is (to be) queued: */
1176 	struct rt_rq		*rt_rq;
1177 	/* rq "owned" by this entity/group: */
1178 	struct rt_rq		*my_q;
1179 #endif
1180 };
1181 
1182 struct rcu_node;
1183 
1184 enum perf_event_task_context {
1185 	perf_invalid_context = -1,
1186 	perf_hw_context = 0,
1187 	perf_sw_context,
1188 	perf_nr_task_contexts,
1189 };
1190 
1191 struct task_struct {
1192 	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
1193 	void *stack;
1194 	atomic_t usage;
1195 	unsigned int flags;	/* per process flags, defined below */
1196 	unsigned int ptrace;
1197 
1198 	int lock_depth;		/* BKL lock depth */
1199 
1200 #ifdef CONFIG_SMP
1201 #ifdef __ARCH_WANT_UNLOCKED_CTXSW
1202 	int oncpu;
1203 #endif
1204 #endif
1205 
1206 	int prio, static_prio, normal_prio;
1207 	unsigned int rt_priority;
1208 	const struct sched_class *sched_class;
1209 	struct sched_entity se;
1210 	struct sched_rt_entity rt;
1211 
1212 #ifdef CONFIG_PREEMPT_NOTIFIERS
1213 	/* list of struct preempt_notifier: */
1214 	struct hlist_head preempt_notifiers;
1215 #endif
1216 
1217 	/*
1218 	 * fpu_counter contains the number of consecutive context switches
1219 	 * that the FPU is used. If this is over a threshold, the lazy fpu
1220 	 * saving becomes unlazy to save the trap. This is an unsigned char
1221 	 * so that after 256 times the counter wraps and the behavior turns
1222 	 * lazy again; this to deal with bursty apps that only use FPU for
1223 	 * a short time
1224 	 */
1225 	unsigned char fpu_counter;
1226 #ifdef CONFIG_BLK_DEV_IO_TRACE
1227 	unsigned int btrace_seq;
1228 #endif
1229 
1230 	unsigned int policy;
1231 	cpumask_t cpus_allowed;
1232 
1233 #ifdef CONFIG_PREEMPT_RCU
1234 	int rcu_read_lock_nesting;
1235 	char rcu_read_unlock_special;
1236 	struct list_head rcu_node_entry;
1237 #endif /* #ifdef CONFIG_PREEMPT_RCU */
1238 #ifdef CONFIG_TREE_PREEMPT_RCU
1239 	struct rcu_node *rcu_blocked_node;
1240 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1241 #ifdef CONFIG_RCU_BOOST
1242 	struct rt_mutex *rcu_boost_mutex;
1243 #endif /* #ifdef CONFIG_RCU_BOOST */
1244 
1245 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1246 	struct sched_info sched_info;
1247 #endif
1248 
1249 	struct list_head tasks;
1250 #ifdef CONFIG_SMP
1251 	struct plist_node pushable_tasks;
1252 #endif
1253 
1254 	struct mm_struct *mm, *active_mm;
1255 #if defined(SPLIT_RSS_COUNTING)
1256 	struct task_rss_stat	rss_stat;
1257 #endif
1258 /* task state */
1259 	int exit_state;
1260 	int exit_code, exit_signal;
1261 	int pdeath_signal;  /*  The signal sent when the parent dies  */
1262 	/* ??? */
1263 	unsigned int personality;
1264 	unsigned did_exec:1;
1265 	unsigned in_execve:1;	/* Tell the LSMs that the process is doing an
1266 				 * execve */
1267 	unsigned in_iowait:1;
1268 
1269 
1270 	/* Revert to default priority/policy when forking */
1271 	unsigned sched_reset_on_fork:1;
1272 
1273 	pid_t pid;
1274 	pid_t tgid;
1275 
1276 #ifdef CONFIG_CC_STACKPROTECTOR
1277 	/* Canary value for the -fstack-protector gcc feature */
1278 	unsigned long stack_canary;
1279 #endif
1280 
1281 	/*
1282 	 * pointers to (original) parent process, youngest child, younger sibling,
1283 	 * older sibling, respectively.  (p->father can be replaced with
1284 	 * p->real_parent->pid)
1285 	 */
1286 	struct task_struct *real_parent; /* real parent process */
1287 	struct task_struct *parent; /* recipient of SIGCHLD, wait4() reports */
1288 	/*
1289 	 * children/sibling forms the list of my natural children
1290 	 */
1291 	struct list_head children;	/* list of my children */
1292 	struct list_head sibling;	/* linkage in my parent's children list */
1293 	struct task_struct *group_leader;	/* threadgroup leader */
1294 
1295 	/*
1296 	 * ptraced is the list of tasks this task is using ptrace on.
1297 	 * This includes both natural children and PTRACE_ATTACH targets.
1298 	 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1299 	 */
1300 	struct list_head ptraced;
1301 	struct list_head ptrace_entry;
1302 
1303 	/* PID/PID hash table linkage. */
1304 	struct pid_link pids[PIDTYPE_MAX];
1305 	struct list_head thread_group;
1306 
1307 	struct completion *vfork_done;		/* for vfork() */
1308 	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
1309 	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
1310 
1311 	cputime_t utime, stime, utimescaled, stimescaled;
1312 	cputime_t gtime;
1313 #ifndef CONFIG_VIRT_CPU_ACCOUNTING
1314 	cputime_t prev_utime, prev_stime;
1315 #endif
1316 	unsigned long nvcsw, nivcsw; /* context switch counts */
1317 	struct timespec start_time; 		/* monotonic time */
1318 	struct timespec real_start_time;	/* boot based time */
1319 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1320 	unsigned long min_flt, maj_flt;
1321 
1322 	struct task_cputime cputime_expires;
1323 	struct list_head cpu_timers[3];
1324 
1325 /* process credentials */
1326 	const struct cred __rcu *real_cred; /* objective and real subjective task
1327 					 * credentials (COW) */
1328 	const struct cred __rcu *cred;	/* effective (overridable) subjective task
1329 					 * credentials (COW) */
1330 	struct cred *replacement_session_keyring; /* for KEYCTL_SESSION_TO_PARENT */
1331 
1332 	char comm[TASK_COMM_LEN]; /* executable name excluding path
1333 				     - access with [gs]et_task_comm (which lock
1334 				       it with task_lock())
1335 				     - initialized normally by setup_new_exec */
1336 /* file system info */
1337 	int link_count, total_link_count;
1338 #ifdef CONFIG_SYSVIPC
1339 /* ipc stuff */
1340 	struct sysv_sem sysvsem;
1341 #endif
1342 #ifdef CONFIG_DETECT_HUNG_TASK
1343 /* hung task detection */
1344 	unsigned long last_switch_count;
1345 #endif
1346 /* CPU-specific state of this task */
1347 	struct thread_struct thread;
1348 /* filesystem information */
1349 	struct fs_struct *fs;
1350 /* open file information */
1351 	struct files_struct *files;
1352 /* namespaces */
1353 	struct nsproxy *nsproxy;
1354 /* signal handlers */
1355 	struct signal_struct *signal;
1356 	struct sighand_struct *sighand;
1357 
1358 	sigset_t blocked, real_blocked;
1359 	sigset_t saved_sigmask;	/* restored if set_restore_sigmask() was used */
1360 	struct sigpending pending;
1361 
1362 	unsigned long sas_ss_sp;
1363 	size_t sas_ss_size;
1364 	int (*notifier)(void *priv);
1365 	void *notifier_data;
1366 	sigset_t *notifier_mask;
1367 	struct audit_context *audit_context;
1368 #ifdef CONFIG_AUDITSYSCALL
1369 	uid_t loginuid;
1370 	unsigned int sessionid;
1371 #endif
1372 	seccomp_t seccomp;
1373 
1374 /* Thread group tracking */
1375    	u32 parent_exec_id;
1376    	u32 self_exec_id;
1377 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1378  * mempolicy */
1379 	spinlock_t alloc_lock;
1380 
1381 #ifdef CONFIG_GENERIC_HARDIRQS
1382 	/* IRQ handler threads */
1383 	struct irqaction *irqaction;
1384 #endif
1385 
1386 	/* Protection of the PI data structures: */
1387 	raw_spinlock_t pi_lock;
1388 
1389 #ifdef CONFIG_RT_MUTEXES
1390 	/* PI waiters blocked on a rt_mutex held by this task */
1391 	struct plist_head pi_waiters;
1392 	/* Deadlock detection and priority inheritance handling */
1393 	struct rt_mutex_waiter *pi_blocked_on;
1394 #endif
1395 
1396 #ifdef CONFIG_DEBUG_MUTEXES
1397 	/* mutex deadlock detection */
1398 	struct mutex_waiter *blocked_on;
1399 #endif
1400 #ifdef CONFIG_TRACE_IRQFLAGS
1401 	unsigned int irq_events;
1402 	unsigned long hardirq_enable_ip;
1403 	unsigned long hardirq_disable_ip;
1404 	unsigned int hardirq_enable_event;
1405 	unsigned int hardirq_disable_event;
1406 	int hardirqs_enabled;
1407 	int hardirq_context;
1408 	unsigned long softirq_disable_ip;
1409 	unsigned long softirq_enable_ip;
1410 	unsigned int softirq_disable_event;
1411 	unsigned int softirq_enable_event;
1412 	int softirqs_enabled;
1413 	int softirq_context;
1414 #endif
1415 #ifdef CONFIG_LOCKDEP
1416 # define MAX_LOCK_DEPTH 48UL
1417 	u64 curr_chain_key;
1418 	int lockdep_depth;
1419 	unsigned int lockdep_recursion;
1420 	struct held_lock held_locks[MAX_LOCK_DEPTH];
1421 	gfp_t lockdep_reclaim_gfp;
1422 #endif
1423 
1424 /* journalling filesystem info */
1425 	void *journal_info;
1426 
1427 /* stacked block device info */
1428 	struct bio_list *bio_list;
1429 
1430 /* VM state */
1431 	struct reclaim_state *reclaim_state;
1432 
1433 	struct backing_dev_info *backing_dev_info;
1434 
1435 	struct io_context *io_context;
1436 
1437 	unsigned long ptrace_message;
1438 	siginfo_t *last_siginfo; /* For ptrace use.  */
1439 	struct task_io_accounting ioac;
1440 #if defined(CONFIG_TASK_XACCT)
1441 	u64 acct_rss_mem1;	/* accumulated rss usage */
1442 	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1443 	cputime_t acct_timexpd;	/* stime + utime since last update */
1444 #endif
1445 #ifdef CONFIG_CPUSETS
1446 	nodemask_t mems_allowed;	/* Protected by alloc_lock */
1447 	int mems_allowed_change_disable;
1448 	int cpuset_mem_spread_rotor;
1449 	int cpuset_slab_spread_rotor;
1450 #endif
1451 #ifdef CONFIG_CGROUPS
1452 	/* Control Group info protected by css_set_lock */
1453 	struct css_set __rcu *cgroups;
1454 	/* cg_list protected by css_set_lock and tsk->alloc_lock */
1455 	struct list_head cg_list;
1456 #endif
1457 #ifdef CONFIG_FUTEX
1458 	struct robust_list_head __user *robust_list;
1459 #ifdef CONFIG_COMPAT
1460 	struct compat_robust_list_head __user *compat_robust_list;
1461 #endif
1462 	struct list_head pi_state_list;
1463 	struct futex_pi_state *pi_state_cache;
1464 #endif
1465 #ifdef CONFIG_PERF_EVENTS
1466 	struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1467 	struct mutex perf_event_mutex;
1468 	struct list_head perf_event_list;
1469 #endif
1470 #ifdef CONFIG_NUMA
1471 	struct mempolicy *mempolicy;	/* Protected by alloc_lock */
1472 	short il_next;
1473 #endif
1474 	atomic_t fs_excl;	/* holding fs exclusive resources */
1475 	struct rcu_head rcu;
1476 
1477 	/*
1478 	 * cache last used pipe for splice
1479 	 */
1480 	struct pipe_inode_info *splice_pipe;
1481 #ifdef	CONFIG_TASK_DELAY_ACCT
1482 	struct task_delay_info *delays;
1483 #endif
1484 #ifdef CONFIG_FAULT_INJECTION
1485 	int make_it_fail;
1486 #endif
1487 	struct prop_local_single dirties;
1488 #ifdef CONFIG_LATENCYTOP
1489 	int latency_record_count;
1490 	struct latency_record latency_record[LT_SAVECOUNT];
1491 #endif
1492 	/*
1493 	 * time slack values; these are used to round up poll() and
1494 	 * select() etc timeout values. These are in nanoseconds.
1495 	 */
1496 	unsigned long timer_slack_ns;
1497 	unsigned long default_timer_slack_ns;
1498 
1499 	struct list_head	*scm_work_list;
1500 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1501 	/* Index of current stored address in ret_stack */
1502 	int curr_ret_stack;
1503 	/* Stack of return addresses for return function tracing */
1504 	struct ftrace_ret_stack	*ret_stack;
1505 	/* time stamp for last schedule */
1506 	unsigned long long ftrace_timestamp;
1507 	/*
1508 	 * Number of functions that haven't been traced
1509 	 * because of depth overrun.
1510 	 */
1511 	atomic_t trace_overrun;
1512 	/* Pause for the tracing */
1513 	atomic_t tracing_graph_pause;
1514 #endif
1515 #ifdef CONFIG_TRACING
1516 	/* state flags for use by tracers */
1517 	unsigned long trace;
1518 	/* bitmask of trace recursion */
1519 	unsigned long trace_recursion;
1520 #endif /* CONFIG_TRACING */
1521 #ifdef CONFIG_CGROUP_MEM_RES_CTLR /* memcg uses this to do batch job */
1522 	struct memcg_batch_info {
1523 		int do_batch;	/* incremented when batch uncharge started */
1524 		struct mem_cgroup *memcg; /* target memcg of uncharge */
1525 		unsigned long bytes; 		/* uncharged usage */
1526 		unsigned long memsw_bytes; /* uncharged mem+swap usage */
1527 	} memcg_batch;
1528 #endif
1529 };
1530 
1531 /* Future-safe accessor for struct task_struct's cpus_allowed. */
1532 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1533 
1534 /*
1535  * Priority of a process goes from 0..MAX_PRIO-1, valid RT
1536  * priority is 0..MAX_RT_PRIO-1, and SCHED_NORMAL/SCHED_BATCH
1537  * tasks are in the range MAX_RT_PRIO..MAX_PRIO-1. Priority
1538  * values are inverted: lower p->prio value means higher priority.
1539  *
1540  * The MAX_USER_RT_PRIO value allows the actual maximum
1541  * RT priority to be separate from the value exported to
1542  * user-space.  This allows kernel threads to set their
1543  * priority to a value higher than any user task. Note:
1544  * MAX_RT_PRIO must not be smaller than MAX_USER_RT_PRIO.
1545  */
1546 
1547 #define MAX_USER_RT_PRIO	100
1548 #define MAX_RT_PRIO		MAX_USER_RT_PRIO
1549 
1550 #define MAX_PRIO		(MAX_RT_PRIO + 40)
1551 #define DEFAULT_PRIO		(MAX_RT_PRIO + 20)
1552 
1553 static inline int rt_prio(int prio)
1554 {
1555 	if (unlikely(prio < MAX_RT_PRIO))
1556 		return 1;
1557 	return 0;
1558 }
1559 
1560 static inline int rt_task(struct task_struct *p)
1561 {
1562 	return rt_prio(p->prio);
1563 }
1564 
1565 static inline struct pid *task_pid(struct task_struct *task)
1566 {
1567 	return task->pids[PIDTYPE_PID].pid;
1568 }
1569 
1570 static inline struct pid *task_tgid(struct task_struct *task)
1571 {
1572 	return task->group_leader->pids[PIDTYPE_PID].pid;
1573 }
1574 
1575 /*
1576  * Without tasklist or rcu lock it is not safe to dereference
1577  * the result of task_pgrp/task_session even if task == current,
1578  * we can race with another thread doing sys_setsid/sys_setpgid.
1579  */
1580 static inline struct pid *task_pgrp(struct task_struct *task)
1581 {
1582 	return task->group_leader->pids[PIDTYPE_PGID].pid;
1583 }
1584 
1585 static inline struct pid *task_session(struct task_struct *task)
1586 {
1587 	return task->group_leader->pids[PIDTYPE_SID].pid;
1588 }
1589 
1590 struct pid_namespace;
1591 
1592 /*
1593  * the helpers to get the task's different pids as they are seen
1594  * from various namespaces
1595  *
1596  * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1597  * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1598  *                     current.
1599  * task_xid_nr_ns()  : id seen from the ns specified;
1600  *
1601  * set_task_vxid()   : assigns a virtual id to a task;
1602  *
1603  * see also pid_nr() etc in include/linux/pid.h
1604  */
1605 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1606 			struct pid_namespace *ns);
1607 
1608 static inline pid_t task_pid_nr(struct task_struct *tsk)
1609 {
1610 	return tsk->pid;
1611 }
1612 
1613 static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1614 					struct pid_namespace *ns)
1615 {
1616 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1617 }
1618 
1619 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1620 {
1621 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1622 }
1623 
1624 
1625 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1626 {
1627 	return tsk->tgid;
1628 }
1629 
1630 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1631 
1632 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1633 {
1634 	return pid_vnr(task_tgid(tsk));
1635 }
1636 
1637 
1638 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1639 					struct pid_namespace *ns)
1640 {
1641 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1642 }
1643 
1644 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1645 {
1646 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1647 }
1648 
1649 
1650 static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1651 					struct pid_namespace *ns)
1652 {
1653 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1654 }
1655 
1656 static inline pid_t task_session_vnr(struct task_struct *tsk)
1657 {
1658 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1659 }
1660 
1661 /* obsolete, do not use */
1662 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1663 {
1664 	return task_pgrp_nr_ns(tsk, &init_pid_ns);
1665 }
1666 
1667 /**
1668  * pid_alive - check that a task structure is not stale
1669  * @p: Task structure to be checked.
1670  *
1671  * Test if a process is not yet dead (at most zombie state)
1672  * If pid_alive fails, then pointers within the task structure
1673  * can be stale and must not be dereferenced.
1674  */
1675 static inline int pid_alive(struct task_struct *p)
1676 {
1677 	return p->pids[PIDTYPE_PID].pid != NULL;
1678 }
1679 
1680 /**
1681  * is_global_init - check if a task structure is init
1682  * @tsk: Task structure to be checked.
1683  *
1684  * Check if a task structure is the first user space task the kernel created.
1685  */
1686 static inline int is_global_init(struct task_struct *tsk)
1687 {
1688 	return tsk->pid == 1;
1689 }
1690 
1691 /*
1692  * is_container_init:
1693  * check whether in the task is init in its own pid namespace.
1694  */
1695 extern int is_container_init(struct task_struct *tsk);
1696 
1697 extern struct pid *cad_pid;
1698 
1699 extern void free_task(struct task_struct *tsk);
1700 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1701 
1702 extern void __put_task_struct(struct task_struct *t);
1703 
1704 static inline void put_task_struct(struct task_struct *t)
1705 {
1706 	if (atomic_dec_and_test(&t->usage))
1707 		__put_task_struct(t);
1708 }
1709 
1710 extern void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1711 extern void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st);
1712 
1713 /*
1714  * Per process flags
1715  */
1716 #define PF_KSOFTIRQD	0x00000001	/* I am ksoftirqd */
1717 #define PF_STARTING	0x00000002	/* being created */
1718 #define PF_EXITING	0x00000004	/* getting shut down */
1719 #define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
1720 #define PF_VCPU		0x00000010	/* I'm a virtual CPU */
1721 #define PF_WQ_WORKER	0x00000020	/* I'm a workqueue worker */
1722 #define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
1723 #define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
1724 #define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
1725 #define PF_DUMPCORE	0x00000200	/* dumped core */
1726 #define PF_SIGNALED	0x00000400	/* killed by a signal */
1727 #define PF_MEMALLOC	0x00000800	/* Allocating memory */
1728 #define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
1729 #define PF_FREEZING	0x00004000	/* freeze in progress. do not account to load */
1730 #define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
1731 #define PF_FROZEN	0x00010000	/* frozen for system suspend */
1732 #define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
1733 #define PF_KSWAPD	0x00040000	/* I am kswapd */
1734 #define PF_OOM_ORIGIN	0x00080000	/* Allocating much memory to others */
1735 #define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
1736 #define PF_KTHREAD	0x00200000	/* I am a kernel thread */
1737 #define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
1738 #define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
1739 #define PF_SPREAD_PAGE	0x01000000	/* Spread page cache over cpuset */
1740 #define PF_SPREAD_SLAB	0x02000000	/* Spread some slab caches over cpuset */
1741 #define PF_THREAD_BOUND	0x04000000	/* Thread bound to specific cpu */
1742 #define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
1743 #define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
1744 #define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
1745 #define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezeable */
1746 #define PF_FREEZER_NOSIG 0x80000000	/* Freezer won't send signals to it */
1747 
1748 /*
1749  * Only the _current_ task can read/write to tsk->flags, but other
1750  * tasks can access tsk->flags in readonly mode for example
1751  * with tsk_used_math (like during threaded core dumping).
1752  * There is however an exception to this rule during ptrace
1753  * or during fork: the ptracer task is allowed to write to the
1754  * child->flags of its traced child (same goes for fork, the parent
1755  * can write to the child->flags), because we're guaranteed the
1756  * child is not running and in turn not changing child->flags
1757  * at the same time the parent does it.
1758  */
1759 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1760 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1761 #define clear_used_math() clear_stopped_child_used_math(current)
1762 #define set_used_math() set_stopped_child_used_math(current)
1763 #define conditional_stopped_child_used_math(condition, child) \
1764 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1765 #define conditional_used_math(condition) \
1766 	conditional_stopped_child_used_math(condition, current)
1767 #define copy_to_stopped_child_used_math(child) \
1768 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1769 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1770 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1771 #define used_math() tsk_used_math(current)
1772 
1773 #ifdef CONFIG_PREEMPT_RCU
1774 
1775 #define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */
1776 #define RCU_READ_UNLOCK_BOOSTED (1 << 1) /* boosted while in RCU read-side. */
1777 #define RCU_READ_UNLOCK_NEED_QS (1 << 2) /* RCU core needs CPU response. */
1778 
1779 static inline void rcu_copy_process(struct task_struct *p)
1780 {
1781 	p->rcu_read_lock_nesting = 0;
1782 	p->rcu_read_unlock_special = 0;
1783 #ifdef CONFIG_TREE_PREEMPT_RCU
1784 	p->rcu_blocked_node = NULL;
1785 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1786 #ifdef CONFIG_RCU_BOOST
1787 	p->rcu_boost_mutex = NULL;
1788 #endif /* #ifdef CONFIG_RCU_BOOST */
1789 	INIT_LIST_HEAD(&p->rcu_node_entry);
1790 }
1791 
1792 #else
1793 
1794 static inline void rcu_copy_process(struct task_struct *p)
1795 {
1796 }
1797 
1798 #endif
1799 
1800 #ifdef CONFIG_SMP
1801 extern int set_cpus_allowed_ptr(struct task_struct *p,
1802 				const struct cpumask *new_mask);
1803 #else
1804 static inline int set_cpus_allowed_ptr(struct task_struct *p,
1805 				       const struct cpumask *new_mask)
1806 {
1807 	if (!cpumask_test_cpu(0, new_mask))
1808 		return -EINVAL;
1809 	return 0;
1810 }
1811 #endif
1812 
1813 #ifndef CONFIG_CPUMASK_OFFSTACK
1814 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1815 {
1816 	return set_cpus_allowed_ptr(p, &new_mask);
1817 }
1818 #endif
1819 
1820 /*
1821  * Do not use outside of architecture code which knows its limitations.
1822  *
1823  * sched_clock() has no promise of monotonicity or bounded drift between
1824  * CPUs, use (which you should not) requires disabling IRQs.
1825  *
1826  * Please use one of the three interfaces below.
1827  */
1828 extern unsigned long long notrace sched_clock(void);
1829 /*
1830  * See the comment in kernel/sched_clock.c
1831  */
1832 extern u64 cpu_clock(int cpu);
1833 extern u64 local_clock(void);
1834 extern u64 sched_clock_cpu(int cpu);
1835 
1836 
1837 extern void sched_clock_init(void);
1838 
1839 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1840 static inline void sched_clock_tick(void)
1841 {
1842 }
1843 
1844 static inline void sched_clock_idle_sleep_event(void)
1845 {
1846 }
1847 
1848 static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
1849 {
1850 }
1851 #else
1852 /*
1853  * Architectures can set this to 1 if they have specified
1854  * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
1855  * but then during bootup it turns out that sched_clock()
1856  * is reliable after all:
1857  */
1858 extern int sched_clock_stable;
1859 
1860 extern void sched_clock_tick(void);
1861 extern void sched_clock_idle_sleep_event(void);
1862 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1863 #endif
1864 
1865 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1866 /*
1867  * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
1868  * The reason for this explicit opt-in is not to have perf penalty with
1869  * slow sched_clocks.
1870  */
1871 extern void enable_sched_clock_irqtime(void);
1872 extern void disable_sched_clock_irqtime(void);
1873 #else
1874 static inline void enable_sched_clock_irqtime(void) {}
1875 static inline void disable_sched_clock_irqtime(void) {}
1876 #endif
1877 
1878 extern unsigned long long
1879 task_sched_runtime(struct task_struct *task);
1880 extern unsigned long long thread_group_sched_runtime(struct task_struct *task);
1881 
1882 /* sched_exec is called by processes performing an exec */
1883 #ifdef CONFIG_SMP
1884 extern void sched_exec(void);
1885 #else
1886 #define sched_exec()   {}
1887 #endif
1888 
1889 extern void sched_clock_idle_sleep_event(void);
1890 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1891 
1892 #ifdef CONFIG_HOTPLUG_CPU
1893 extern void idle_task_exit(void);
1894 #else
1895 static inline void idle_task_exit(void) {}
1896 #endif
1897 
1898 #if defined(CONFIG_NO_HZ) && defined(CONFIG_SMP)
1899 extern void wake_up_idle_cpu(int cpu);
1900 #else
1901 static inline void wake_up_idle_cpu(int cpu) { }
1902 #endif
1903 
1904 extern unsigned int sysctl_sched_latency;
1905 extern unsigned int sysctl_sched_min_granularity;
1906 extern unsigned int sysctl_sched_wakeup_granularity;
1907 extern unsigned int sysctl_sched_child_runs_first;
1908 
1909 enum sched_tunable_scaling {
1910 	SCHED_TUNABLESCALING_NONE,
1911 	SCHED_TUNABLESCALING_LOG,
1912 	SCHED_TUNABLESCALING_LINEAR,
1913 	SCHED_TUNABLESCALING_END,
1914 };
1915 extern enum sched_tunable_scaling sysctl_sched_tunable_scaling;
1916 
1917 #ifdef CONFIG_SCHED_DEBUG
1918 extern unsigned int sysctl_sched_migration_cost;
1919 extern unsigned int sysctl_sched_nr_migrate;
1920 extern unsigned int sysctl_sched_time_avg;
1921 extern unsigned int sysctl_timer_migration;
1922 extern unsigned int sysctl_sched_shares_window;
1923 
1924 int sched_proc_update_handler(struct ctl_table *table, int write,
1925 		void __user *buffer, size_t *length,
1926 		loff_t *ppos);
1927 #endif
1928 #ifdef CONFIG_SCHED_DEBUG
1929 static inline unsigned int get_sysctl_timer_migration(void)
1930 {
1931 	return sysctl_timer_migration;
1932 }
1933 #else
1934 static inline unsigned int get_sysctl_timer_migration(void)
1935 {
1936 	return 1;
1937 }
1938 #endif
1939 extern unsigned int sysctl_sched_rt_period;
1940 extern int sysctl_sched_rt_runtime;
1941 
1942 int sched_rt_handler(struct ctl_table *table, int write,
1943 		void __user *buffer, size_t *lenp,
1944 		loff_t *ppos);
1945 
1946 extern unsigned int sysctl_sched_compat_yield;
1947 
1948 #ifdef CONFIG_SCHED_AUTOGROUP
1949 extern unsigned int sysctl_sched_autogroup_enabled;
1950 
1951 extern void sched_autogroup_create_attach(struct task_struct *p);
1952 extern void sched_autogroup_detach(struct task_struct *p);
1953 extern void sched_autogroup_fork(struct signal_struct *sig);
1954 extern void sched_autogroup_exit(struct signal_struct *sig);
1955 #ifdef CONFIG_PROC_FS
1956 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
1957 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int *nice);
1958 #endif
1959 #else
1960 static inline void sched_autogroup_create_attach(struct task_struct *p) { }
1961 static inline void sched_autogroup_detach(struct task_struct *p) { }
1962 static inline void sched_autogroup_fork(struct signal_struct *sig) { }
1963 static inline void sched_autogroup_exit(struct signal_struct *sig) { }
1964 #endif
1965 
1966 #ifdef CONFIG_RT_MUTEXES
1967 extern int rt_mutex_getprio(struct task_struct *p);
1968 extern void rt_mutex_setprio(struct task_struct *p, int prio);
1969 extern void rt_mutex_adjust_pi(struct task_struct *p);
1970 #else
1971 static inline int rt_mutex_getprio(struct task_struct *p)
1972 {
1973 	return p->normal_prio;
1974 }
1975 # define rt_mutex_adjust_pi(p)		do { } while (0)
1976 #endif
1977 
1978 extern void set_user_nice(struct task_struct *p, long nice);
1979 extern int task_prio(const struct task_struct *p);
1980 extern int task_nice(const struct task_struct *p);
1981 extern int can_nice(const struct task_struct *p, const int nice);
1982 extern int task_curr(const struct task_struct *p);
1983 extern int idle_cpu(int cpu);
1984 extern int sched_setscheduler(struct task_struct *, int,
1985 			      const struct sched_param *);
1986 extern int sched_setscheduler_nocheck(struct task_struct *, int,
1987 				      const struct sched_param *);
1988 extern struct task_struct *idle_task(int cpu);
1989 extern struct task_struct *curr_task(int cpu);
1990 extern void set_curr_task(int cpu, struct task_struct *p);
1991 
1992 void yield(void);
1993 
1994 /*
1995  * The default (Linux) execution domain.
1996  */
1997 extern struct exec_domain	default_exec_domain;
1998 
1999 union thread_union {
2000 	struct thread_info thread_info;
2001 	unsigned long stack[THREAD_SIZE/sizeof(long)];
2002 };
2003 
2004 #ifndef __HAVE_ARCH_KSTACK_END
2005 static inline int kstack_end(void *addr)
2006 {
2007 	/* Reliable end of stack detection:
2008 	 * Some APM bios versions misalign the stack
2009 	 */
2010 	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
2011 }
2012 #endif
2013 
2014 extern union thread_union init_thread_union;
2015 extern struct task_struct init_task;
2016 
2017 extern struct   mm_struct init_mm;
2018 
2019 extern struct pid_namespace init_pid_ns;
2020 
2021 /*
2022  * find a task by one of its numerical ids
2023  *
2024  * find_task_by_pid_ns():
2025  *      finds a task by its pid in the specified namespace
2026  * find_task_by_vpid():
2027  *      finds a task by its virtual pid
2028  *
2029  * see also find_vpid() etc in include/linux/pid.h
2030  */
2031 
2032 extern struct task_struct *find_task_by_vpid(pid_t nr);
2033 extern struct task_struct *find_task_by_pid_ns(pid_t nr,
2034 		struct pid_namespace *ns);
2035 
2036 extern void __set_special_pids(struct pid *pid);
2037 
2038 /* per-UID process charging. */
2039 extern struct user_struct * alloc_uid(struct user_namespace *, uid_t);
2040 static inline struct user_struct *get_uid(struct user_struct *u)
2041 {
2042 	atomic_inc(&u->__count);
2043 	return u;
2044 }
2045 extern void free_uid(struct user_struct *);
2046 extern void release_uids(struct user_namespace *ns);
2047 
2048 #include <asm/current.h>
2049 
2050 extern void do_timer(unsigned long ticks);
2051 
2052 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2053 extern int wake_up_process(struct task_struct *tsk);
2054 extern void wake_up_new_task(struct task_struct *tsk,
2055 				unsigned long clone_flags);
2056 #ifdef CONFIG_SMP
2057  extern void kick_process(struct task_struct *tsk);
2058 #else
2059  static inline void kick_process(struct task_struct *tsk) { }
2060 #endif
2061 extern void sched_fork(struct task_struct *p, int clone_flags);
2062 extern void sched_dead(struct task_struct *p);
2063 
2064 extern void proc_caches_init(void);
2065 extern void flush_signals(struct task_struct *);
2066 extern void __flush_signals(struct task_struct *);
2067 extern void ignore_signals(struct task_struct *);
2068 extern void flush_signal_handlers(struct task_struct *, int force_default);
2069 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2070 
2071 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
2072 {
2073 	unsigned long flags;
2074 	int ret;
2075 
2076 	spin_lock_irqsave(&tsk->sighand->siglock, flags);
2077 	ret = dequeue_signal(tsk, mask, info);
2078 	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
2079 
2080 	return ret;
2081 }
2082 
2083 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
2084 			      sigset_t *mask);
2085 extern void unblock_all_signals(void);
2086 extern void release_task(struct task_struct * p);
2087 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2088 extern int force_sigsegv(int, struct task_struct *);
2089 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2090 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2091 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2092 extern int kill_pid_info_as_uid(int, struct siginfo *, struct pid *, uid_t, uid_t, u32);
2093 extern int kill_pgrp(struct pid *pid, int sig, int priv);
2094 extern int kill_pid(struct pid *pid, int sig, int priv);
2095 extern int kill_proc_info(int, struct siginfo *, pid_t);
2096 extern int do_notify_parent(struct task_struct *, int);
2097 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2098 extern void force_sig(int, struct task_struct *);
2099 extern int send_sig(int, struct task_struct *, int);
2100 extern int zap_other_threads(struct task_struct *p);
2101 extern struct sigqueue *sigqueue_alloc(void);
2102 extern void sigqueue_free(struct sigqueue *);
2103 extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
2104 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2105 extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned long);
2106 
2107 static inline int kill_cad_pid(int sig, int priv)
2108 {
2109 	return kill_pid(cad_pid, sig, priv);
2110 }
2111 
2112 /* These can be the second arg to send_sig_info/send_group_sig_info.  */
2113 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
2114 #define SEND_SIG_PRIV	((struct siginfo *) 1)
2115 #define SEND_SIG_FORCED	((struct siginfo *) 2)
2116 
2117 /*
2118  * True if we are on the alternate signal stack.
2119  */
2120 static inline int on_sig_stack(unsigned long sp)
2121 {
2122 #ifdef CONFIG_STACK_GROWSUP
2123 	return sp >= current->sas_ss_sp &&
2124 		sp - current->sas_ss_sp < current->sas_ss_size;
2125 #else
2126 	return sp > current->sas_ss_sp &&
2127 		sp - current->sas_ss_sp <= current->sas_ss_size;
2128 #endif
2129 }
2130 
2131 static inline int sas_ss_flags(unsigned long sp)
2132 {
2133 	return (current->sas_ss_size == 0 ? SS_DISABLE
2134 		: on_sig_stack(sp) ? SS_ONSTACK : 0);
2135 }
2136 
2137 /*
2138  * Routines for handling mm_structs
2139  */
2140 extern struct mm_struct * mm_alloc(void);
2141 
2142 /* mmdrop drops the mm and the page tables */
2143 extern void __mmdrop(struct mm_struct *);
2144 static inline void mmdrop(struct mm_struct * mm)
2145 {
2146 	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2147 		__mmdrop(mm);
2148 }
2149 
2150 /* mmput gets rid of the mappings and all user-space */
2151 extern void mmput(struct mm_struct *);
2152 /* Grab a reference to a task's mm, if it is not already going away */
2153 extern struct mm_struct *get_task_mm(struct task_struct *task);
2154 /* Remove the current tasks stale references to the old mm_struct */
2155 extern void mm_release(struct task_struct *, struct mm_struct *);
2156 /* Allocate a new mm structure and copy contents from tsk->mm */
2157 extern struct mm_struct *dup_mm(struct task_struct *tsk);
2158 
2159 extern int copy_thread(unsigned long, unsigned long, unsigned long,
2160 			struct task_struct *, struct pt_regs *);
2161 extern void flush_thread(void);
2162 extern void exit_thread(void);
2163 
2164 extern void exit_files(struct task_struct *);
2165 extern void __cleanup_sighand(struct sighand_struct *);
2166 
2167 extern void exit_itimers(struct signal_struct *);
2168 extern void flush_itimer_signals(void);
2169 
2170 extern NORET_TYPE void do_group_exit(int);
2171 
2172 extern void daemonize(const char *, ...);
2173 extern int allow_signal(int);
2174 extern int disallow_signal(int);
2175 
2176 extern int do_execve(const char *,
2177 		     const char __user * const __user *,
2178 		     const char __user * const __user *, struct pt_regs *);
2179 extern long do_fork(unsigned long, unsigned long, struct pt_regs *, unsigned long, int __user *, int __user *);
2180 struct task_struct *fork_idle(int);
2181 
2182 extern void set_task_comm(struct task_struct *tsk, char *from);
2183 extern char *get_task_comm(char *to, struct task_struct *tsk);
2184 
2185 #ifdef CONFIG_SMP
2186 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2187 #else
2188 static inline unsigned long wait_task_inactive(struct task_struct *p,
2189 					       long match_state)
2190 {
2191 	return 1;
2192 }
2193 #endif
2194 
2195 #define next_task(p) \
2196 	list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2197 
2198 #define for_each_process(p) \
2199 	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2200 
2201 extern bool current_is_single_threaded(void);
2202 
2203 /*
2204  * Careful: do_each_thread/while_each_thread is a double loop so
2205  *          'break' will not work as expected - use goto instead.
2206  */
2207 #define do_each_thread(g, t) \
2208 	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2209 
2210 #define while_each_thread(g, t) \
2211 	while ((t = next_thread(t)) != g)
2212 
2213 static inline int get_nr_threads(struct task_struct *tsk)
2214 {
2215 	return tsk->signal->nr_threads;
2216 }
2217 
2218 /* de_thread depends on thread_group_leader not being a pid based check */
2219 #define thread_group_leader(p)	(p == p->group_leader)
2220 
2221 /* Do to the insanities of de_thread it is possible for a process
2222  * to have the pid of the thread group leader without actually being
2223  * the thread group leader.  For iteration through the pids in proc
2224  * all we care about is that we have a task with the appropriate
2225  * pid, we don't actually care if we have the right task.
2226  */
2227 static inline int has_group_leader_pid(struct task_struct *p)
2228 {
2229 	return p->pid == p->tgid;
2230 }
2231 
2232 static inline
2233 int same_thread_group(struct task_struct *p1, struct task_struct *p2)
2234 {
2235 	return p1->tgid == p2->tgid;
2236 }
2237 
2238 static inline struct task_struct *next_thread(const struct task_struct *p)
2239 {
2240 	return list_entry_rcu(p->thread_group.next,
2241 			      struct task_struct, thread_group);
2242 }
2243 
2244 static inline int thread_group_empty(struct task_struct *p)
2245 {
2246 	return list_empty(&p->thread_group);
2247 }
2248 
2249 #define delay_group_leader(p) \
2250 		(thread_group_leader(p) && !thread_group_empty(p))
2251 
2252 static inline int task_detached(struct task_struct *p)
2253 {
2254 	return p->exit_signal == -1;
2255 }
2256 
2257 /*
2258  * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2259  * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2260  * pins the final release of task.io_context.  Also protects ->cpuset and
2261  * ->cgroup.subsys[].
2262  *
2263  * Nests both inside and outside of read_lock(&tasklist_lock).
2264  * It must not be nested with write_lock_irq(&tasklist_lock),
2265  * neither inside nor outside.
2266  */
2267 static inline void task_lock(struct task_struct *p)
2268 {
2269 	spin_lock(&p->alloc_lock);
2270 }
2271 
2272 static inline void task_unlock(struct task_struct *p)
2273 {
2274 	spin_unlock(&p->alloc_lock);
2275 }
2276 
2277 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2278 							unsigned long *flags);
2279 
2280 #define lock_task_sighand(tsk, flags)					\
2281 ({	struct sighand_struct *__ss;					\
2282 	__cond_lock(&(tsk)->sighand->siglock,				\
2283 		    (__ss = __lock_task_sighand(tsk, flags)));		\
2284 	__ss;								\
2285 })									\
2286 
2287 static inline void unlock_task_sighand(struct task_struct *tsk,
2288 						unsigned long *flags)
2289 {
2290 	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2291 }
2292 
2293 #ifndef __HAVE_THREAD_FUNCTIONS
2294 
2295 #define task_thread_info(task)	((struct thread_info *)(task)->stack)
2296 #define task_stack_page(task)	((task)->stack)
2297 
2298 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2299 {
2300 	*task_thread_info(p) = *task_thread_info(org);
2301 	task_thread_info(p)->task = p;
2302 }
2303 
2304 static inline unsigned long *end_of_stack(struct task_struct *p)
2305 {
2306 	return (unsigned long *)(task_thread_info(p) + 1);
2307 }
2308 
2309 #endif
2310 
2311 static inline int object_is_on_stack(void *obj)
2312 {
2313 	void *stack = task_stack_page(current);
2314 
2315 	return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2316 }
2317 
2318 extern void thread_info_cache_init(void);
2319 
2320 #ifdef CONFIG_DEBUG_STACK_USAGE
2321 static inline unsigned long stack_not_used(struct task_struct *p)
2322 {
2323 	unsigned long *n = end_of_stack(p);
2324 
2325 	do { 	/* Skip over canary */
2326 		n++;
2327 	} while (!*n);
2328 
2329 	return (unsigned long)n - (unsigned long)end_of_stack(p);
2330 }
2331 #endif
2332 
2333 /* set thread flags in other task's structures
2334  * - see asm/thread_info.h for TIF_xxxx flags available
2335  */
2336 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2337 {
2338 	set_ti_thread_flag(task_thread_info(tsk), flag);
2339 }
2340 
2341 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2342 {
2343 	clear_ti_thread_flag(task_thread_info(tsk), flag);
2344 }
2345 
2346 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2347 {
2348 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2349 }
2350 
2351 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2352 {
2353 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2354 }
2355 
2356 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2357 {
2358 	return test_ti_thread_flag(task_thread_info(tsk), flag);
2359 }
2360 
2361 static inline void set_tsk_need_resched(struct task_struct *tsk)
2362 {
2363 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2364 }
2365 
2366 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2367 {
2368 	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2369 }
2370 
2371 static inline int test_tsk_need_resched(struct task_struct *tsk)
2372 {
2373 	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2374 }
2375 
2376 static inline int restart_syscall(void)
2377 {
2378 	set_tsk_thread_flag(current, TIF_SIGPENDING);
2379 	return -ERESTARTNOINTR;
2380 }
2381 
2382 static inline int signal_pending(struct task_struct *p)
2383 {
2384 	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2385 }
2386 
2387 static inline int __fatal_signal_pending(struct task_struct *p)
2388 {
2389 	return unlikely(sigismember(&p->pending.signal, SIGKILL));
2390 }
2391 
2392 static inline int fatal_signal_pending(struct task_struct *p)
2393 {
2394 	return signal_pending(p) && __fatal_signal_pending(p);
2395 }
2396 
2397 static inline int signal_pending_state(long state, struct task_struct *p)
2398 {
2399 	if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2400 		return 0;
2401 	if (!signal_pending(p))
2402 		return 0;
2403 
2404 	return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2405 }
2406 
2407 static inline int need_resched(void)
2408 {
2409 	return unlikely(test_thread_flag(TIF_NEED_RESCHED));
2410 }
2411 
2412 /*
2413  * cond_resched() and cond_resched_lock(): latency reduction via
2414  * explicit rescheduling in places that are safe. The return
2415  * value indicates whether a reschedule was done in fact.
2416  * cond_resched_lock() will drop the spinlock before scheduling,
2417  * cond_resched_softirq() will enable bhs before scheduling.
2418  */
2419 extern int _cond_resched(void);
2420 
2421 #define cond_resched() ({			\
2422 	__might_sleep(__FILE__, __LINE__, 0);	\
2423 	_cond_resched();			\
2424 })
2425 
2426 extern int __cond_resched_lock(spinlock_t *lock);
2427 
2428 #ifdef CONFIG_PREEMPT
2429 #define PREEMPT_LOCK_OFFSET	PREEMPT_OFFSET
2430 #else
2431 #define PREEMPT_LOCK_OFFSET	0
2432 #endif
2433 
2434 #define cond_resched_lock(lock) ({				\
2435 	__might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);	\
2436 	__cond_resched_lock(lock);				\
2437 })
2438 
2439 extern int __cond_resched_softirq(void);
2440 
2441 #define cond_resched_softirq() ({					\
2442 	__might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET);	\
2443 	__cond_resched_softirq();					\
2444 })
2445 
2446 /*
2447  * Does a critical section need to be broken due to another
2448  * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2449  * but a general need for low latency)
2450  */
2451 static inline int spin_needbreak(spinlock_t *lock)
2452 {
2453 #ifdef CONFIG_PREEMPT
2454 	return spin_is_contended(lock);
2455 #else
2456 	return 0;
2457 #endif
2458 }
2459 
2460 /*
2461  * Thread group CPU time accounting.
2462  */
2463 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2464 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2465 
2466 static inline void thread_group_cputime_init(struct signal_struct *sig)
2467 {
2468 	spin_lock_init(&sig->cputimer.lock);
2469 }
2470 
2471 /*
2472  * Reevaluate whether the task has signals pending delivery.
2473  * Wake the task if so.
2474  * This is required every time the blocked sigset_t changes.
2475  * callers must hold sighand->siglock.
2476  */
2477 extern void recalc_sigpending_and_wake(struct task_struct *t);
2478 extern void recalc_sigpending(void);
2479 
2480 extern void signal_wake_up(struct task_struct *t, int resume_stopped);
2481 
2482 /*
2483  * Wrappers for p->thread_info->cpu access. No-op on UP.
2484  */
2485 #ifdef CONFIG_SMP
2486 
2487 static inline unsigned int task_cpu(const struct task_struct *p)
2488 {
2489 	return task_thread_info(p)->cpu;
2490 }
2491 
2492 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2493 
2494 #else
2495 
2496 static inline unsigned int task_cpu(const struct task_struct *p)
2497 {
2498 	return 0;
2499 }
2500 
2501 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2502 {
2503 }
2504 
2505 #endif /* CONFIG_SMP */
2506 
2507 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2508 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2509 
2510 extern void normalize_rt_tasks(void);
2511 
2512 #ifdef CONFIG_CGROUP_SCHED
2513 
2514 extern struct task_group root_task_group;
2515 
2516 extern struct task_group *sched_create_group(struct task_group *parent);
2517 extern void sched_destroy_group(struct task_group *tg);
2518 extern void sched_move_task(struct task_struct *tsk);
2519 #ifdef CONFIG_FAIR_GROUP_SCHED
2520 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
2521 extern unsigned long sched_group_shares(struct task_group *tg);
2522 #endif
2523 #ifdef CONFIG_RT_GROUP_SCHED
2524 extern int sched_group_set_rt_runtime(struct task_group *tg,
2525 				      long rt_runtime_us);
2526 extern long sched_group_rt_runtime(struct task_group *tg);
2527 extern int sched_group_set_rt_period(struct task_group *tg,
2528 				      long rt_period_us);
2529 extern long sched_group_rt_period(struct task_group *tg);
2530 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
2531 #endif
2532 #endif
2533 
2534 extern int task_can_switch_user(struct user_struct *up,
2535 					struct task_struct *tsk);
2536 
2537 #ifdef CONFIG_TASK_XACCT
2538 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2539 {
2540 	tsk->ioac.rchar += amt;
2541 }
2542 
2543 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2544 {
2545 	tsk->ioac.wchar += amt;
2546 }
2547 
2548 static inline void inc_syscr(struct task_struct *tsk)
2549 {
2550 	tsk->ioac.syscr++;
2551 }
2552 
2553 static inline void inc_syscw(struct task_struct *tsk)
2554 {
2555 	tsk->ioac.syscw++;
2556 }
2557 #else
2558 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2559 {
2560 }
2561 
2562 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2563 {
2564 }
2565 
2566 static inline void inc_syscr(struct task_struct *tsk)
2567 {
2568 }
2569 
2570 static inline void inc_syscw(struct task_struct *tsk)
2571 {
2572 }
2573 #endif
2574 
2575 #ifndef TASK_SIZE_OF
2576 #define TASK_SIZE_OF(tsk)	TASK_SIZE
2577 #endif
2578 
2579 /*
2580  * Call the function if the target task is executing on a CPU right now:
2581  */
2582 extern void task_oncpu_function_call(struct task_struct *p,
2583 				     void (*func) (void *info), void *info);
2584 
2585 
2586 #ifdef CONFIG_MM_OWNER
2587 extern void mm_update_next_owner(struct mm_struct *mm);
2588 extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2589 #else
2590 static inline void mm_update_next_owner(struct mm_struct *mm)
2591 {
2592 }
2593 
2594 static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2595 {
2596 }
2597 #endif /* CONFIG_MM_OWNER */
2598 
2599 static inline unsigned long task_rlimit(const struct task_struct *tsk,
2600 		unsigned int limit)
2601 {
2602 	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur);
2603 }
2604 
2605 static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
2606 		unsigned int limit)
2607 {
2608 	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max);
2609 }
2610 
2611 static inline unsigned long rlimit(unsigned int limit)
2612 {
2613 	return task_rlimit(current, limit);
2614 }
2615 
2616 static inline unsigned long rlimit_max(unsigned int limit)
2617 {
2618 	return task_rlimit_max(current, limit);
2619 }
2620 
2621 #endif /* __KERNEL__ */
2622 
2623 #endif
2624