xref: /linux-6.15/include/linux/sched.h (revision 12eb4683)
1 #ifndef _LINUX_SCHED_H
2 #define _LINUX_SCHED_H
3 
4 #include <uapi/linux/sched.h>
5 
6 
7 struct sched_param {
8 	int sched_priority;
9 };
10 
11 #include <asm/param.h>	/* for HZ */
12 
13 #include <linux/capability.h>
14 #include <linux/threads.h>
15 #include <linux/kernel.h>
16 #include <linux/types.h>
17 #include <linux/timex.h>
18 #include <linux/jiffies.h>
19 #include <linux/rbtree.h>
20 #include <linux/thread_info.h>
21 #include <linux/cpumask.h>
22 #include <linux/errno.h>
23 #include <linux/nodemask.h>
24 #include <linux/mm_types.h>
25 #include <linux/preempt_mask.h>
26 
27 #include <asm/page.h>
28 #include <asm/ptrace.h>
29 #include <asm/cputime.h>
30 
31 #include <linux/smp.h>
32 #include <linux/sem.h>
33 #include <linux/signal.h>
34 #include <linux/compiler.h>
35 #include <linux/completion.h>
36 #include <linux/pid.h>
37 #include <linux/percpu.h>
38 #include <linux/topology.h>
39 #include <linux/proportions.h>
40 #include <linux/seccomp.h>
41 #include <linux/rcupdate.h>
42 #include <linux/rculist.h>
43 #include <linux/rtmutex.h>
44 
45 #include <linux/time.h>
46 #include <linux/param.h>
47 #include <linux/resource.h>
48 #include <linux/timer.h>
49 #include <linux/hrtimer.h>
50 #include <linux/task_io_accounting.h>
51 #include <linux/latencytop.h>
52 #include <linux/cred.h>
53 #include <linux/llist.h>
54 #include <linux/uidgid.h>
55 #include <linux/gfp.h>
56 
57 #include <asm/processor.h>
58 
59 struct exec_domain;
60 struct futex_pi_state;
61 struct robust_list_head;
62 struct bio_list;
63 struct fs_struct;
64 struct perf_event_context;
65 struct blk_plug;
66 
67 /*
68  * List of flags we want to share for kernel threads,
69  * if only because they are not used by them anyway.
70  */
71 #define CLONE_KERNEL	(CLONE_FS | CLONE_FILES | CLONE_SIGHAND)
72 
73 /*
74  * These are the constant used to fake the fixed-point load-average
75  * counting. Some notes:
76  *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
77  *    a load-average precision of 10 bits integer + 11 bits fractional
78  *  - if you want to count load-averages more often, you need more
79  *    precision, or rounding will get you. With 2-second counting freq,
80  *    the EXP_n values would be 1981, 2034 and 2043 if still using only
81  *    11 bit fractions.
82  */
83 extern unsigned long avenrun[];		/* Load averages */
84 extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
85 
86 #define FSHIFT		11		/* nr of bits of precision */
87 #define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
88 #define LOAD_FREQ	(5*HZ+1)	/* 5 sec intervals */
89 #define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
90 #define EXP_5		2014		/* 1/exp(5sec/5min) */
91 #define EXP_15		2037		/* 1/exp(5sec/15min) */
92 
93 #define CALC_LOAD(load,exp,n) \
94 	load *= exp; \
95 	load += n*(FIXED_1-exp); \
96 	load >>= FSHIFT;
97 
98 extern unsigned long total_forks;
99 extern int nr_threads;
100 DECLARE_PER_CPU(unsigned long, process_counts);
101 extern int nr_processes(void);
102 extern unsigned long nr_running(void);
103 extern unsigned long nr_iowait(void);
104 extern unsigned long nr_iowait_cpu(int cpu);
105 extern unsigned long this_cpu_load(void);
106 
107 
108 extern void calc_global_load(unsigned long ticks);
109 extern void update_cpu_load_nohz(void);
110 
111 extern unsigned long get_parent_ip(unsigned long addr);
112 
113 extern void dump_cpu_task(int cpu);
114 
115 struct seq_file;
116 struct cfs_rq;
117 struct task_group;
118 #ifdef CONFIG_SCHED_DEBUG
119 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
120 extern void proc_sched_set_task(struct task_struct *p);
121 extern void
122 print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
123 #endif
124 
125 /*
126  * Task state bitmask. NOTE! These bits are also
127  * encoded in fs/proc/array.c: get_task_state().
128  *
129  * We have two separate sets of flags: task->state
130  * is about runnability, while task->exit_state are
131  * about the task exiting. Confusing, but this way
132  * modifying one set can't modify the other one by
133  * mistake.
134  */
135 #define TASK_RUNNING		0
136 #define TASK_INTERRUPTIBLE	1
137 #define TASK_UNINTERRUPTIBLE	2
138 #define __TASK_STOPPED		4
139 #define __TASK_TRACED		8
140 /* in tsk->exit_state */
141 #define EXIT_ZOMBIE		16
142 #define EXIT_DEAD		32
143 /* in tsk->state again */
144 #define TASK_DEAD		64
145 #define TASK_WAKEKILL		128
146 #define TASK_WAKING		256
147 #define TASK_PARKED		512
148 #define TASK_STATE_MAX		1024
149 
150 #define TASK_STATE_TO_CHAR_STR "RSDTtZXxKWP"
151 
152 extern char ___assert_task_state[1 - 2*!!(
153 		sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
154 
155 /* Convenience macros for the sake of set_task_state */
156 #define TASK_KILLABLE		(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
157 #define TASK_STOPPED		(TASK_WAKEKILL | __TASK_STOPPED)
158 #define TASK_TRACED		(TASK_WAKEKILL | __TASK_TRACED)
159 
160 /* Convenience macros for the sake of wake_up */
161 #define TASK_NORMAL		(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
162 #define TASK_ALL		(TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
163 
164 /* get_task_state() */
165 #define TASK_REPORT		(TASK_RUNNING | TASK_INTERRUPTIBLE | \
166 				 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
167 				 __TASK_TRACED)
168 
169 #define task_is_traced(task)	((task->state & __TASK_TRACED) != 0)
170 #define task_is_stopped(task)	((task->state & __TASK_STOPPED) != 0)
171 #define task_is_dead(task)	((task)->exit_state != 0)
172 #define task_is_stopped_or_traced(task)	\
173 			((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
174 #define task_contributes_to_load(task)	\
175 				((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
176 				 (task->flags & PF_FROZEN) == 0)
177 
178 #define __set_task_state(tsk, state_value)		\
179 	do { (tsk)->state = (state_value); } while (0)
180 #define set_task_state(tsk, state_value)		\
181 	set_mb((tsk)->state, (state_value))
182 
183 /*
184  * set_current_state() includes a barrier so that the write of current->state
185  * is correctly serialised wrt the caller's subsequent test of whether to
186  * actually sleep:
187  *
188  *	set_current_state(TASK_UNINTERRUPTIBLE);
189  *	if (do_i_need_to_sleep())
190  *		schedule();
191  *
192  * If the caller does not need such serialisation then use __set_current_state()
193  */
194 #define __set_current_state(state_value)			\
195 	do { current->state = (state_value); } while (0)
196 #define set_current_state(state_value)		\
197 	set_mb(current->state, (state_value))
198 
199 /* Task command name length */
200 #define TASK_COMM_LEN 16
201 
202 #include <linux/spinlock.h>
203 
204 /*
205  * This serializes "schedule()" and also protects
206  * the run-queue from deletions/modifications (but
207  * _adding_ to the beginning of the run-queue has
208  * a separate lock).
209  */
210 extern rwlock_t tasklist_lock;
211 extern spinlock_t mmlist_lock;
212 
213 struct task_struct;
214 
215 #ifdef CONFIG_PROVE_RCU
216 extern int lockdep_tasklist_lock_is_held(void);
217 #endif /* #ifdef CONFIG_PROVE_RCU */
218 
219 extern void sched_init(void);
220 extern void sched_init_smp(void);
221 extern asmlinkage void schedule_tail(struct task_struct *prev);
222 extern void init_idle(struct task_struct *idle, int cpu);
223 extern void init_idle_bootup_task(struct task_struct *idle);
224 
225 extern int runqueue_is_locked(int cpu);
226 
227 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
228 extern void nohz_balance_enter_idle(int cpu);
229 extern void set_cpu_sd_state_idle(void);
230 extern int get_nohz_timer_target(void);
231 #else
232 static inline void nohz_balance_enter_idle(int cpu) { }
233 static inline void set_cpu_sd_state_idle(void) { }
234 #endif
235 
236 /*
237  * Only dump TASK_* tasks. (0 for all tasks)
238  */
239 extern void show_state_filter(unsigned long state_filter);
240 
241 static inline void show_state(void)
242 {
243 	show_state_filter(0);
244 }
245 
246 extern void show_regs(struct pt_regs *);
247 
248 /*
249  * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
250  * task), SP is the stack pointer of the first frame that should be shown in the back
251  * trace (or NULL if the entire call-chain of the task should be shown).
252  */
253 extern void show_stack(struct task_struct *task, unsigned long *sp);
254 
255 void io_schedule(void);
256 long io_schedule_timeout(long timeout);
257 
258 extern void cpu_init (void);
259 extern void trap_init(void);
260 extern void update_process_times(int user);
261 extern void scheduler_tick(void);
262 
263 extern void sched_show_task(struct task_struct *p);
264 
265 #ifdef CONFIG_LOCKUP_DETECTOR
266 extern void touch_softlockup_watchdog(void);
267 extern void touch_softlockup_watchdog_sync(void);
268 extern void touch_all_softlockup_watchdogs(void);
269 extern int proc_dowatchdog_thresh(struct ctl_table *table, int write,
270 				  void __user *buffer,
271 				  size_t *lenp, loff_t *ppos);
272 extern unsigned int  softlockup_panic;
273 void lockup_detector_init(void);
274 #else
275 static inline void touch_softlockup_watchdog(void)
276 {
277 }
278 static inline void touch_softlockup_watchdog_sync(void)
279 {
280 }
281 static inline void touch_all_softlockup_watchdogs(void)
282 {
283 }
284 static inline void lockup_detector_init(void)
285 {
286 }
287 #endif
288 
289 #ifdef CONFIG_DETECT_HUNG_TASK
290 void reset_hung_task_detector(void);
291 #else
292 static inline void reset_hung_task_detector(void)
293 {
294 }
295 #endif
296 
297 /* Attach to any functions which should be ignored in wchan output. */
298 #define __sched		__attribute__((__section__(".sched.text")))
299 
300 /* Linker adds these: start and end of __sched functions */
301 extern char __sched_text_start[], __sched_text_end[];
302 
303 /* Is this address in the __sched functions? */
304 extern int in_sched_functions(unsigned long addr);
305 
306 #define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
307 extern signed long schedule_timeout(signed long timeout);
308 extern signed long schedule_timeout_interruptible(signed long timeout);
309 extern signed long schedule_timeout_killable(signed long timeout);
310 extern signed long schedule_timeout_uninterruptible(signed long timeout);
311 asmlinkage void schedule(void);
312 extern void schedule_preempt_disabled(void);
313 
314 struct nsproxy;
315 struct user_namespace;
316 
317 #ifdef CONFIG_MMU
318 extern void arch_pick_mmap_layout(struct mm_struct *mm);
319 extern unsigned long
320 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
321 		       unsigned long, unsigned long);
322 extern unsigned long
323 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
324 			  unsigned long len, unsigned long pgoff,
325 			  unsigned long flags);
326 #else
327 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
328 #endif
329 
330 
331 extern void set_dumpable(struct mm_struct *mm, int value);
332 extern int get_dumpable(struct mm_struct *mm);
333 
334 #define SUID_DUMP_DISABLE	0	/* No setuid dumping */
335 #define SUID_DUMP_USER		1	/* Dump as user of process */
336 #define SUID_DUMP_ROOT		2	/* Dump as root */
337 
338 /* mm flags */
339 /* dumpable bits */
340 #define MMF_DUMPABLE      0  /* core dump is permitted */
341 #define MMF_DUMP_SECURELY 1  /* core file is readable only by root */
342 
343 #define MMF_DUMPABLE_BITS 2
344 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
345 
346 /* coredump filter bits */
347 #define MMF_DUMP_ANON_PRIVATE	2
348 #define MMF_DUMP_ANON_SHARED	3
349 #define MMF_DUMP_MAPPED_PRIVATE	4
350 #define MMF_DUMP_MAPPED_SHARED	5
351 #define MMF_DUMP_ELF_HEADERS	6
352 #define MMF_DUMP_HUGETLB_PRIVATE 7
353 #define MMF_DUMP_HUGETLB_SHARED  8
354 
355 #define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
356 #define MMF_DUMP_FILTER_BITS	7
357 #define MMF_DUMP_FILTER_MASK \
358 	(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
359 #define MMF_DUMP_FILTER_DEFAULT \
360 	((1 << MMF_DUMP_ANON_PRIVATE) |	(1 << MMF_DUMP_ANON_SHARED) |\
361 	 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
362 
363 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
364 # define MMF_DUMP_MASK_DEFAULT_ELF	(1 << MMF_DUMP_ELF_HEADERS)
365 #else
366 # define MMF_DUMP_MASK_DEFAULT_ELF	0
367 #endif
368 					/* leave room for more dump flags */
369 #define MMF_VM_MERGEABLE	16	/* KSM may merge identical pages */
370 #define MMF_VM_HUGEPAGE		17	/* set when VM_HUGEPAGE is set on vma */
371 #define MMF_EXE_FILE_CHANGED	18	/* see prctl_set_mm_exe_file() */
372 
373 #define MMF_HAS_UPROBES		19	/* has uprobes */
374 #define MMF_RECALC_UPROBES	20	/* MMF_HAS_UPROBES can be wrong */
375 
376 #define MMF_INIT_MASK		(MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
377 
378 struct sighand_struct {
379 	atomic_t		count;
380 	struct k_sigaction	action[_NSIG];
381 	spinlock_t		siglock;
382 	wait_queue_head_t	signalfd_wqh;
383 };
384 
385 struct pacct_struct {
386 	int			ac_flag;
387 	long			ac_exitcode;
388 	unsigned long		ac_mem;
389 	cputime_t		ac_utime, ac_stime;
390 	unsigned long		ac_minflt, ac_majflt;
391 };
392 
393 struct cpu_itimer {
394 	cputime_t expires;
395 	cputime_t incr;
396 	u32 error;
397 	u32 incr_error;
398 };
399 
400 /**
401  * struct cputime - snaphsot of system and user cputime
402  * @utime: time spent in user mode
403  * @stime: time spent in system mode
404  *
405  * Gathers a generic snapshot of user and system time.
406  */
407 struct cputime {
408 	cputime_t utime;
409 	cputime_t stime;
410 };
411 
412 /**
413  * struct task_cputime - collected CPU time counts
414  * @utime:		time spent in user mode, in &cputime_t units
415  * @stime:		time spent in kernel mode, in &cputime_t units
416  * @sum_exec_runtime:	total time spent on the CPU, in nanoseconds
417  *
418  * This is an extension of struct cputime that includes the total runtime
419  * spent by the task from the scheduler point of view.
420  *
421  * As a result, this structure groups together three kinds of CPU time
422  * that are tracked for threads and thread groups.  Most things considering
423  * CPU time want to group these counts together and treat all three
424  * of them in parallel.
425  */
426 struct task_cputime {
427 	cputime_t utime;
428 	cputime_t stime;
429 	unsigned long long sum_exec_runtime;
430 };
431 /* Alternate field names when used to cache expirations. */
432 #define prof_exp	stime
433 #define virt_exp	utime
434 #define sched_exp	sum_exec_runtime
435 
436 #define INIT_CPUTIME	\
437 	(struct task_cputime) {					\
438 		.utime = 0,					\
439 		.stime = 0,					\
440 		.sum_exec_runtime = 0,				\
441 	}
442 
443 #define PREEMPT_ENABLED		(PREEMPT_NEED_RESCHED)
444 
445 #ifdef CONFIG_PREEMPT_COUNT
446 #define PREEMPT_DISABLED	(1 + PREEMPT_ENABLED)
447 #else
448 #define PREEMPT_DISABLED	PREEMPT_ENABLED
449 #endif
450 
451 /*
452  * Disable preemption until the scheduler is running.
453  * Reset by start_kernel()->sched_init()->init_idle().
454  *
455  * We include PREEMPT_ACTIVE to avoid cond_resched() from working
456  * before the scheduler is active -- see should_resched().
457  */
458 #define INIT_PREEMPT_COUNT	(PREEMPT_DISABLED + PREEMPT_ACTIVE)
459 
460 /**
461  * struct thread_group_cputimer - thread group interval timer counts
462  * @cputime:		thread group interval timers.
463  * @running:		non-zero when there are timers running and
464  * 			@cputime receives updates.
465  * @lock:		lock for fields in this struct.
466  *
467  * This structure contains the version of task_cputime, above, that is
468  * used for thread group CPU timer calculations.
469  */
470 struct thread_group_cputimer {
471 	struct task_cputime cputime;
472 	int running;
473 	raw_spinlock_t lock;
474 };
475 
476 #include <linux/rwsem.h>
477 struct autogroup;
478 
479 /*
480  * NOTE! "signal_struct" does not have its own
481  * locking, because a shared signal_struct always
482  * implies a shared sighand_struct, so locking
483  * sighand_struct is always a proper superset of
484  * the locking of signal_struct.
485  */
486 struct signal_struct {
487 	atomic_t		sigcnt;
488 	atomic_t		live;
489 	int			nr_threads;
490 
491 	wait_queue_head_t	wait_chldexit;	/* for wait4() */
492 
493 	/* current thread group signal load-balancing target: */
494 	struct task_struct	*curr_target;
495 
496 	/* shared signal handling: */
497 	struct sigpending	shared_pending;
498 
499 	/* thread group exit support */
500 	int			group_exit_code;
501 	/* overloaded:
502 	 * - notify group_exit_task when ->count is equal to notify_count
503 	 * - everyone except group_exit_task is stopped during signal delivery
504 	 *   of fatal signals, group_exit_task processes the signal.
505 	 */
506 	int			notify_count;
507 	struct task_struct	*group_exit_task;
508 
509 	/* thread group stop support, overloads group_exit_code too */
510 	int			group_stop_count;
511 	unsigned int		flags; /* see SIGNAL_* flags below */
512 
513 	/*
514 	 * PR_SET_CHILD_SUBREAPER marks a process, like a service
515 	 * manager, to re-parent orphan (double-forking) child processes
516 	 * to this process instead of 'init'. The service manager is
517 	 * able to receive SIGCHLD signals and is able to investigate
518 	 * the process until it calls wait(). All children of this
519 	 * process will inherit a flag if they should look for a
520 	 * child_subreaper process at exit.
521 	 */
522 	unsigned int		is_child_subreaper:1;
523 	unsigned int		has_child_subreaper:1;
524 
525 	/* POSIX.1b Interval Timers */
526 	int			posix_timer_id;
527 	struct list_head	posix_timers;
528 
529 	/* ITIMER_REAL timer for the process */
530 	struct hrtimer real_timer;
531 	struct pid *leader_pid;
532 	ktime_t it_real_incr;
533 
534 	/*
535 	 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
536 	 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
537 	 * values are defined to 0 and 1 respectively
538 	 */
539 	struct cpu_itimer it[2];
540 
541 	/*
542 	 * Thread group totals for process CPU timers.
543 	 * See thread_group_cputimer(), et al, for details.
544 	 */
545 	struct thread_group_cputimer cputimer;
546 
547 	/* Earliest-expiration cache. */
548 	struct task_cputime cputime_expires;
549 
550 	struct list_head cpu_timers[3];
551 
552 	struct pid *tty_old_pgrp;
553 
554 	/* boolean value for session group leader */
555 	int leader;
556 
557 	struct tty_struct *tty; /* NULL if no tty */
558 
559 #ifdef CONFIG_SCHED_AUTOGROUP
560 	struct autogroup *autogroup;
561 #endif
562 	/*
563 	 * Cumulative resource counters for dead threads in the group,
564 	 * and for reaped dead child processes forked by this group.
565 	 * Live threads maintain their own counters and add to these
566 	 * in __exit_signal, except for the group leader.
567 	 */
568 	cputime_t utime, stime, cutime, cstime;
569 	cputime_t gtime;
570 	cputime_t cgtime;
571 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
572 	struct cputime prev_cputime;
573 #endif
574 	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
575 	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
576 	unsigned long inblock, oublock, cinblock, coublock;
577 	unsigned long maxrss, cmaxrss;
578 	struct task_io_accounting ioac;
579 
580 	/*
581 	 * Cumulative ns of schedule CPU time fo dead threads in the
582 	 * group, not including a zombie group leader, (This only differs
583 	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
584 	 * other than jiffies.)
585 	 */
586 	unsigned long long sum_sched_runtime;
587 
588 	/*
589 	 * We don't bother to synchronize most readers of this at all,
590 	 * because there is no reader checking a limit that actually needs
591 	 * to get both rlim_cur and rlim_max atomically, and either one
592 	 * alone is a single word that can safely be read normally.
593 	 * getrlimit/setrlimit use task_lock(current->group_leader) to
594 	 * protect this instead of the siglock, because they really
595 	 * have no need to disable irqs.
596 	 */
597 	struct rlimit rlim[RLIM_NLIMITS];
598 
599 #ifdef CONFIG_BSD_PROCESS_ACCT
600 	struct pacct_struct pacct;	/* per-process accounting information */
601 #endif
602 #ifdef CONFIG_TASKSTATS
603 	struct taskstats *stats;
604 #endif
605 #ifdef CONFIG_AUDIT
606 	unsigned audit_tty;
607 	unsigned audit_tty_log_passwd;
608 	struct tty_audit_buf *tty_audit_buf;
609 #endif
610 #ifdef CONFIG_CGROUPS
611 	/*
612 	 * group_rwsem prevents new tasks from entering the threadgroup and
613 	 * member tasks from exiting,a more specifically, setting of
614 	 * PF_EXITING.  fork and exit paths are protected with this rwsem
615 	 * using threadgroup_change_begin/end().  Users which require
616 	 * threadgroup to remain stable should use threadgroup_[un]lock()
617 	 * which also takes care of exec path.  Currently, cgroup is the
618 	 * only user.
619 	 */
620 	struct rw_semaphore group_rwsem;
621 #endif
622 
623 	oom_flags_t oom_flags;
624 	short oom_score_adj;		/* OOM kill score adjustment */
625 	short oom_score_adj_min;	/* OOM kill score adjustment min value.
626 					 * Only settable by CAP_SYS_RESOURCE. */
627 
628 	struct mutex cred_guard_mutex;	/* guard against foreign influences on
629 					 * credential calculations
630 					 * (notably. ptrace) */
631 };
632 
633 /*
634  * Bits in flags field of signal_struct.
635  */
636 #define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
637 #define SIGNAL_STOP_CONTINUED	0x00000002 /* SIGCONT since WCONTINUED reap */
638 #define SIGNAL_GROUP_EXIT	0x00000004 /* group exit in progress */
639 #define SIGNAL_GROUP_COREDUMP	0x00000008 /* coredump in progress */
640 /*
641  * Pending notifications to parent.
642  */
643 #define SIGNAL_CLD_STOPPED	0x00000010
644 #define SIGNAL_CLD_CONTINUED	0x00000020
645 #define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
646 
647 #define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */
648 
649 /* If true, all threads except ->group_exit_task have pending SIGKILL */
650 static inline int signal_group_exit(const struct signal_struct *sig)
651 {
652 	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
653 		(sig->group_exit_task != NULL);
654 }
655 
656 /*
657  * Some day this will be a full-fledged user tracking system..
658  */
659 struct user_struct {
660 	atomic_t __count;	/* reference count */
661 	atomic_t processes;	/* How many processes does this user have? */
662 	atomic_t files;		/* How many open files does this user have? */
663 	atomic_t sigpending;	/* How many pending signals does this user have? */
664 #ifdef CONFIG_INOTIFY_USER
665 	atomic_t inotify_watches; /* How many inotify watches does this user have? */
666 	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
667 #endif
668 #ifdef CONFIG_FANOTIFY
669 	atomic_t fanotify_listeners;
670 #endif
671 #ifdef CONFIG_EPOLL
672 	atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
673 #endif
674 #ifdef CONFIG_POSIX_MQUEUE
675 	/* protected by mq_lock	*/
676 	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
677 #endif
678 	unsigned long locked_shm; /* How many pages of mlocked shm ? */
679 
680 #ifdef CONFIG_KEYS
681 	struct key *uid_keyring;	/* UID specific keyring */
682 	struct key *session_keyring;	/* UID's default session keyring */
683 #endif
684 
685 	/* Hash table maintenance information */
686 	struct hlist_node uidhash_node;
687 	kuid_t uid;
688 
689 #ifdef CONFIG_PERF_EVENTS
690 	atomic_long_t locked_vm;
691 #endif
692 };
693 
694 extern int uids_sysfs_init(void);
695 
696 extern struct user_struct *find_user(kuid_t);
697 
698 extern struct user_struct root_user;
699 #define INIT_USER (&root_user)
700 
701 
702 struct backing_dev_info;
703 struct reclaim_state;
704 
705 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
706 struct sched_info {
707 	/* cumulative counters */
708 	unsigned long pcount;	      /* # of times run on this cpu */
709 	unsigned long long run_delay; /* time spent waiting on a runqueue */
710 
711 	/* timestamps */
712 	unsigned long long last_arrival,/* when we last ran on a cpu */
713 			   last_queued;	/* when we were last queued to run */
714 };
715 #endif /* defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT) */
716 
717 #ifdef CONFIG_TASK_DELAY_ACCT
718 struct task_delay_info {
719 	spinlock_t	lock;
720 	unsigned int	flags;	/* Private per-task flags */
721 
722 	/* For each stat XXX, add following, aligned appropriately
723 	 *
724 	 * struct timespec XXX_start, XXX_end;
725 	 * u64 XXX_delay;
726 	 * u32 XXX_count;
727 	 *
728 	 * Atomicity of updates to XXX_delay, XXX_count protected by
729 	 * single lock above (split into XXX_lock if contention is an issue).
730 	 */
731 
732 	/*
733 	 * XXX_count is incremented on every XXX operation, the delay
734 	 * associated with the operation is added to XXX_delay.
735 	 * XXX_delay contains the accumulated delay time in nanoseconds.
736 	 */
737 	struct timespec blkio_start, blkio_end;	/* Shared by blkio, swapin */
738 	u64 blkio_delay;	/* wait for sync block io completion */
739 	u64 swapin_delay;	/* wait for swapin block io completion */
740 	u32 blkio_count;	/* total count of the number of sync block */
741 				/* io operations performed */
742 	u32 swapin_count;	/* total count of the number of swapin block */
743 				/* io operations performed */
744 
745 	struct timespec freepages_start, freepages_end;
746 	u64 freepages_delay;	/* wait for memory reclaim */
747 	u32 freepages_count;	/* total count of memory reclaim */
748 };
749 #endif	/* CONFIG_TASK_DELAY_ACCT */
750 
751 static inline int sched_info_on(void)
752 {
753 #ifdef CONFIG_SCHEDSTATS
754 	return 1;
755 #elif defined(CONFIG_TASK_DELAY_ACCT)
756 	extern int delayacct_on;
757 	return delayacct_on;
758 #else
759 	return 0;
760 #endif
761 }
762 
763 enum cpu_idle_type {
764 	CPU_IDLE,
765 	CPU_NOT_IDLE,
766 	CPU_NEWLY_IDLE,
767 	CPU_MAX_IDLE_TYPES
768 };
769 
770 /*
771  * Increase resolution of cpu_power calculations
772  */
773 #define SCHED_POWER_SHIFT	10
774 #define SCHED_POWER_SCALE	(1L << SCHED_POWER_SHIFT)
775 
776 /*
777  * sched-domains (multiprocessor balancing) declarations:
778  */
779 #ifdef CONFIG_SMP
780 #define SD_LOAD_BALANCE		0x0001	/* Do load balancing on this domain. */
781 #define SD_BALANCE_NEWIDLE	0x0002	/* Balance when about to become idle */
782 #define SD_BALANCE_EXEC		0x0004	/* Balance on exec */
783 #define SD_BALANCE_FORK		0x0008	/* Balance on fork, clone */
784 #define SD_BALANCE_WAKE		0x0010  /* Balance on wakeup */
785 #define SD_WAKE_AFFINE		0x0020	/* Wake task to waking CPU */
786 #define SD_SHARE_CPUPOWER	0x0080	/* Domain members share cpu power */
787 #define SD_SHARE_PKG_RESOURCES	0x0200	/* Domain members share cpu pkg resources */
788 #define SD_SERIALIZE		0x0400	/* Only a single load balancing instance */
789 #define SD_ASYM_PACKING		0x0800  /* Place busy groups earlier in the domain */
790 #define SD_PREFER_SIBLING	0x1000	/* Prefer to place tasks in a sibling domain */
791 #define SD_OVERLAP		0x2000	/* sched_domains of this level overlap */
792 #define SD_NUMA			0x4000	/* cross-node balancing */
793 
794 extern int __weak arch_sd_sibiling_asym_packing(void);
795 
796 struct sched_domain_attr {
797 	int relax_domain_level;
798 };
799 
800 #define SD_ATTR_INIT	(struct sched_domain_attr) {	\
801 	.relax_domain_level = -1,			\
802 }
803 
804 extern int sched_domain_level_max;
805 
806 struct sched_group;
807 
808 struct sched_domain {
809 	/* These fields must be setup */
810 	struct sched_domain *parent;	/* top domain must be null terminated */
811 	struct sched_domain *child;	/* bottom domain must be null terminated */
812 	struct sched_group *groups;	/* the balancing groups of the domain */
813 	unsigned long min_interval;	/* Minimum balance interval ms */
814 	unsigned long max_interval;	/* Maximum balance interval ms */
815 	unsigned int busy_factor;	/* less balancing by factor if busy */
816 	unsigned int imbalance_pct;	/* No balance until over watermark */
817 	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
818 	unsigned int busy_idx;
819 	unsigned int idle_idx;
820 	unsigned int newidle_idx;
821 	unsigned int wake_idx;
822 	unsigned int forkexec_idx;
823 	unsigned int smt_gain;
824 
825 	int nohz_idle;			/* NOHZ IDLE status */
826 	int flags;			/* See SD_* */
827 	int level;
828 
829 	/* Runtime fields. */
830 	unsigned long last_balance;	/* init to jiffies. units in jiffies */
831 	unsigned int balance_interval;	/* initialise to 1. units in ms. */
832 	unsigned int nr_balance_failed; /* initialise to 0 */
833 
834 	/* idle_balance() stats */
835 	u64 max_newidle_lb_cost;
836 	unsigned long next_decay_max_lb_cost;
837 
838 #ifdef CONFIG_SCHEDSTATS
839 	/* load_balance() stats */
840 	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
841 	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
842 	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
843 	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
844 	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
845 	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
846 	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
847 	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
848 
849 	/* Active load balancing */
850 	unsigned int alb_count;
851 	unsigned int alb_failed;
852 	unsigned int alb_pushed;
853 
854 	/* SD_BALANCE_EXEC stats */
855 	unsigned int sbe_count;
856 	unsigned int sbe_balanced;
857 	unsigned int sbe_pushed;
858 
859 	/* SD_BALANCE_FORK stats */
860 	unsigned int sbf_count;
861 	unsigned int sbf_balanced;
862 	unsigned int sbf_pushed;
863 
864 	/* try_to_wake_up() stats */
865 	unsigned int ttwu_wake_remote;
866 	unsigned int ttwu_move_affine;
867 	unsigned int ttwu_move_balance;
868 #endif
869 #ifdef CONFIG_SCHED_DEBUG
870 	char *name;
871 #endif
872 	union {
873 		void *private;		/* used during construction */
874 		struct rcu_head rcu;	/* used during destruction */
875 	};
876 
877 	unsigned int span_weight;
878 	/*
879 	 * Span of all CPUs in this domain.
880 	 *
881 	 * NOTE: this field is variable length. (Allocated dynamically
882 	 * by attaching extra space to the end of the structure,
883 	 * depending on how many CPUs the kernel has booted up with)
884 	 */
885 	unsigned long span[0];
886 };
887 
888 static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
889 {
890 	return to_cpumask(sd->span);
891 }
892 
893 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
894 				    struct sched_domain_attr *dattr_new);
895 
896 /* Allocate an array of sched domains, for partition_sched_domains(). */
897 cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
898 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
899 
900 bool cpus_share_cache(int this_cpu, int that_cpu);
901 
902 #else /* CONFIG_SMP */
903 
904 struct sched_domain_attr;
905 
906 static inline void
907 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
908 			struct sched_domain_attr *dattr_new)
909 {
910 }
911 
912 static inline bool cpus_share_cache(int this_cpu, int that_cpu)
913 {
914 	return true;
915 }
916 
917 #endif	/* !CONFIG_SMP */
918 
919 
920 struct io_context;			/* See blkdev.h */
921 
922 
923 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
924 extern void prefetch_stack(struct task_struct *t);
925 #else
926 static inline void prefetch_stack(struct task_struct *t) { }
927 #endif
928 
929 struct audit_context;		/* See audit.c */
930 struct mempolicy;
931 struct pipe_inode_info;
932 struct uts_namespace;
933 
934 struct load_weight {
935 	unsigned long weight, inv_weight;
936 };
937 
938 struct sched_avg {
939 	/*
940 	 * These sums represent an infinite geometric series and so are bound
941 	 * above by 1024/(1-y).  Thus we only need a u32 to store them for all
942 	 * choices of y < 1-2^(-32)*1024.
943 	 */
944 	u32 runnable_avg_sum, runnable_avg_period;
945 	u64 last_runnable_update;
946 	s64 decay_count;
947 	unsigned long load_avg_contrib;
948 };
949 
950 #ifdef CONFIG_SCHEDSTATS
951 struct sched_statistics {
952 	u64			wait_start;
953 	u64			wait_max;
954 	u64			wait_count;
955 	u64			wait_sum;
956 	u64			iowait_count;
957 	u64			iowait_sum;
958 
959 	u64			sleep_start;
960 	u64			sleep_max;
961 	s64			sum_sleep_runtime;
962 
963 	u64			block_start;
964 	u64			block_max;
965 	u64			exec_max;
966 	u64			slice_max;
967 
968 	u64			nr_migrations_cold;
969 	u64			nr_failed_migrations_affine;
970 	u64			nr_failed_migrations_running;
971 	u64			nr_failed_migrations_hot;
972 	u64			nr_forced_migrations;
973 
974 	u64			nr_wakeups;
975 	u64			nr_wakeups_sync;
976 	u64			nr_wakeups_migrate;
977 	u64			nr_wakeups_local;
978 	u64			nr_wakeups_remote;
979 	u64			nr_wakeups_affine;
980 	u64			nr_wakeups_affine_attempts;
981 	u64			nr_wakeups_passive;
982 	u64			nr_wakeups_idle;
983 };
984 #endif
985 
986 struct sched_entity {
987 	struct load_weight	load;		/* for load-balancing */
988 	struct rb_node		run_node;
989 	struct list_head	group_node;
990 	unsigned int		on_rq;
991 
992 	u64			exec_start;
993 	u64			sum_exec_runtime;
994 	u64			vruntime;
995 	u64			prev_sum_exec_runtime;
996 
997 	u64			nr_migrations;
998 
999 #ifdef CONFIG_SCHEDSTATS
1000 	struct sched_statistics statistics;
1001 #endif
1002 
1003 #ifdef CONFIG_FAIR_GROUP_SCHED
1004 	struct sched_entity	*parent;
1005 	/* rq on which this entity is (to be) queued: */
1006 	struct cfs_rq		*cfs_rq;
1007 	/* rq "owned" by this entity/group: */
1008 	struct cfs_rq		*my_q;
1009 #endif
1010 
1011 #ifdef CONFIG_SMP
1012 	/* Per-entity load-tracking */
1013 	struct sched_avg	avg;
1014 #endif
1015 };
1016 
1017 struct sched_rt_entity {
1018 	struct list_head run_list;
1019 	unsigned long timeout;
1020 	unsigned long watchdog_stamp;
1021 	unsigned int time_slice;
1022 
1023 	struct sched_rt_entity *back;
1024 #ifdef CONFIG_RT_GROUP_SCHED
1025 	struct sched_rt_entity	*parent;
1026 	/* rq on which this entity is (to be) queued: */
1027 	struct rt_rq		*rt_rq;
1028 	/* rq "owned" by this entity/group: */
1029 	struct rt_rq		*my_q;
1030 #endif
1031 };
1032 
1033 
1034 struct rcu_node;
1035 
1036 enum perf_event_task_context {
1037 	perf_invalid_context = -1,
1038 	perf_hw_context = 0,
1039 	perf_sw_context,
1040 	perf_nr_task_contexts,
1041 };
1042 
1043 struct task_struct {
1044 	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
1045 	void *stack;
1046 	atomic_t usage;
1047 	unsigned int flags;	/* per process flags, defined below */
1048 	unsigned int ptrace;
1049 
1050 #ifdef CONFIG_SMP
1051 	struct llist_node wake_entry;
1052 	int on_cpu;
1053 	struct task_struct *last_wakee;
1054 	unsigned long wakee_flips;
1055 	unsigned long wakee_flip_decay_ts;
1056 
1057 	int wake_cpu;
1058 #endif
1059 	int on_rq;
1060 
1061 	int prio, static_prio, normal_prio;
1062 	unsigned int rt_priority;
1063 	const struct sched_class *sched_class;
1064 	struct sched_entity se;
1065 	struct sched_rt_entity rt;
1066 #ifdef CONFIG_CGROUP_SCHED
1067 	struct task_group *sched_task_group;
1068 #endif
1069 
1070 #ifdef CONFIG_PREEMPT_NOTIFIERS
1071 	/* list of struct preempt_notifier: */
1072 	struct hlist_head preempt_notifiers;
1073 #endif
1074 
1075 #ifdef CONFIG_BLK_DEV_IO_TRACE
1076 	unsigned int btrace_seq;
1077 #endif
1078 
1079 	unsigned int policy;
1080 	int nr_cpus_allowed;
1081 	cpumask_t cpus_allowed;
1082 
1083 #ifdef CONFIG_PREEMPT_RCU
1084 	int rcu_read_lock_nesting;
1085 	char rcu_read_unlock_special;
1086 	struct list_head rcu_node_entry;
1087 #endif /* #ifdef CONFIG_PREEMPT_RCU */
1088 #ifdef CONFIG_TREE_PREEMPT_RCU
1089 	struct rcu_node *rcu_blocked_node;
1090 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1091 #ifdef CONFIG_RCU_BOOST
1092 	struct rt_mutex *rcu_boost_mutex;
1093 #endif /* #ifdef CONFIG_RCU_BOOST */
1094 
1095 #if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
1096 	struct sched_info sched_info;
1097 #endif
1098 
1099 	struct list_head tasks;
1100 #ifdef CONFIG_SMP
1101 	struct plist_node pushable_tasks;
1102 #endif
1103 
1104 	struct mm_struct *mm, *active_mm;
1105 #ifdef CONFIG_COMPAT_BRK
1106 	unsigned brk_randomized:1;
1107 #endif
1108 #if defined(SPLIT_RSS_COUNTING)
1109 	struct task_rss_stat	rss_stat;
1110 #endif
1111 /* task state */
1112 	int exit_state;
1113 	int exit_code, exit_signal;
1114 	int pdeath_signal;  /*  The signal sent when the parent dies  */
1115 	unsigned int jobctl;	/* JOBCTL_*, siglock protected */
1116 
1117 	/* Used for emulating ABI behavior of previous Linux versions */
1118 	unsigned int personality;
1119 
1120 	unsigned did_exec:1;
1121 	unsigned in_execve:1;	/* Tell the LSMs that the process is doing an
1122 				 * execve */
1123 	unsigned in_iowait:1;
1124 
1125 	/* task may not gain privileges */
1126 	unsigned no_new_privs:1;
1127 
1128 	/* Revert to default priority/policy when forking */
1129 	unsigned sched_reset_on_fork:1;
1130 	unsigned sched_contributes_to_load:1;
1131 
1132 	pid_t pid;
1133 	pid_t tgid;
1134 
1135 #ifdef CONFIG_CC_STACKPROTECTOR
1136 	/* Canary value for the -fstack-protector gcc feature */
1137 	unsigned long stack_canary;
1138 #endif
1139 	/*
1140 	 * pointers to (original) parent process, youngest child, younger sibling,
1141 	 * older sibling, respectively.  (p->father can be replaced with
1142 	 * p->real_parent->pid)
1143 	 */
1144 	struct task_struct __rcu *real_parent; /* real parent process */
1145 	struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */
1146 	/*
1147 	 * children/sibling forms the list of my natural children
1148 	 */
1149 	struct list_head children;	/* list of my children */
1150 	struct list_head sibling;	/* linkage in my parent's children list */
1151 	struct task_struct *group_leader;	/* threadgroup leader */
1152 
1153 	/*
1154 	 * ptraced is the list of tasks this task is using ptrace on.
1155 	 * This includes both natural children and PTRACE_ATTACH targets.
1156 	 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1157 	 */
1158 	struct list_head ptraced;
1159 	struct list_head ptrace_entry;
1160 
1161 	/* PID/PID hash table linkage. */
1162 	struct pid_link pids[PIDTYPE_MAX];
1163 	struct list_head thread_group;
1164 
1165 	struct completion *vfork_done;		/* for vfork() */
1166 	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
1167 	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
1168 
1169 	cputime_t utime, stime, utimescaled, stimescaled;
1170 	cputime_t gtime;
1171 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
1172 	struct cputime prev_cputime;
1173 #endif
1174 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1175 	seqlock_t vtime_seqlock;
1176 	unsigned long long vtime_snap;
1177 	enum {
1178 		VTIME_SLEEPING = 0,
1179 		VTIME_USER,
1180 		VTIME_SYS,
1181 	} vtime_snap_whence;
1182 #endif
1183 	unsigned long nvcsw, nivcsw; /* context switch counts */
1184 	struct timespec start_time; 		/* monotonic time */
1185 	struct timespec real_start_time;	/* boot based time */
1186 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1187 	unsigned long min_flt, maj_flt;
1188 
1189 	struct task_cputime cputime_expires;
1190 	struct list_head cpu_timers[3];
1191 
1192 /* process credentials */
1193 	const struct cred __rcu *real_cred; /* objective and real subjective task
1194 					 * credentials (COW) */
1195 	const struct cred __rcu *cred;	/* effective (overridable) subjective task
1196 					 * credentials (COW) */
1197 	char comm[TASK_COMM_LEN]; /* executable name excluding path
1198 				     - access with [gs]et_task_comm (which lock
1199 				       it with task_lock())
1200 				     - initialized normally by setup_new_exec */
1201 /* file system info */
1202 	int link_count, total_link_count;
1203 #ifdef CONFIG_SYSVIPC
1204 /* ipc stuff */
1205 	struct sysv_sem sysvsem;
1206 #endif
1207 #ifdef CONFIG_DETECT_HUNG_TASK
1208 /* hung task detection */
1209 	unsigned long last_switch_count;
1210 #endif
1211 /* CPU-specific state of this task */
1212 	struct thread_struct thread;
1213 /* filesystem information */
1214 	struct fs_struct *fs;
1215 /* open file information */
1216 	struct files_struct *files;
1217 /* namespaces */
1218 	struct nsproxy *nsproxy;
1219 /* signal handlers */
1220 	struct signal_struct *signal;
1221 	struct sighand_struct *sighand;
1222 
1223 	sigset_t blocked, real_blocked;
1224 	sigset_t saved_sigmask;	/* restored if set_restore_sigmask() was used */
1225 	struct sigpending pending;
1226 
1227 	unsigned long sas_ss_sp;
1228 	size_t sas_ss_size;
1229 	int (*notifier)(void *priv);
1230 	void *notifier_data;
1231 	sigset_t *notifier_mask;
1232 	struct callback_head *task_works;
1233 
1234 	struct audit_context *audit_context;
1235 #ifdef CONFIG_AUDITSYSCALL
1236 	kuid_t loginuid;
1237 	unsigned int sessionid;
1238 #endif
1239 	struct seccomp seccomp;
1240 
1241 /* Thread group tracking */
1242    	u32 parent_exec_id;
1243    	u32 self_exec_id;
1244 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1245  * mempolicy */
1246 	spinlock_t alloc_lock;
1247 
1248 	/* Protection of the PI data structures: */
1249 	raw_spinlock_t pi_lock;
1250 
1251 #ifdef CONFIG_RT_MUTEXES
1252 	/* PI waiters blocked on a rt_mutex held by this task */
1253 	struct plist_head pi_waiters;
1254 	/* Deadlock detection and priority inheritance handling */
1255 	struct rt_mutex_waiter *pi_blocked_on;
1256 #endif
1257 
1258 #ifdef CONFIG_DEBUG_MUTEXES
1259 	/* mutex deadlock detection */
1260 	struct mutex_waiter *blocked_on;
1261 #endif
1262 #ifdef CONFIG_TRACE_IRQFLAGS
1263 	unsigned int irq_events;
1264 	unsigned long hardirq_enable_ip;
1265 	unsigned long hardirq_disable_ip;
1266 	unsigned int hardirq_enable_event;
1267 	unsigned int hardirq_disable_event;
1268 	int hardirqs_enabled;
1269 	int hardirq_context;
1270 	unsigned long softirq_disable_ip;
1271 	unsigned long softirq_enable_ip;
1272 	unsigned int softirq_disable_event;
1273 	unsigned int softirq_enable_event;
1274 	int softirqs_enabled;
1275 	int softirq_context;
1276 #endif
1277 #ifdef CONFIG_LOCKDEP
1278 # define MAX_LOCK_DEPTH 48UL
1279 	u64 curr_chain_key;
1280 	int lockdep_depth;
1281 	unsigned int lockdep_recursion;
1282 	struct held_lock held_locks[MAX_LOCK_DEPTH];
1283 	gfp_t lockdep_reclaim_gfp;
1284 #endif
1285 
1286 /* journalling filesystem info */
1287 	void *journal_info;
1288 
1289 /* stacked block device info */
1290 	struct bio_list *bio_list;
1291 
1292 #ifdef CONFIG_BLOCK
1293 /* stack plugging */
1294 	struct blk_plug *plug;
1295 #endif
1296 
1297 /* VM state */
1298 	struct reclaim_state *reclaim_state;
1299 
1300 	struct backing_dev_info *backing_dev_info;
1301 
1302 	struct io_context *io_context;
1303 
1304 	unsigned long ptrace_message;
1305 	siginfo_t *last_siginfo; /* For ptrace use.  */
1306 	struct task_io_accounting ioac;
1307 #if defined(CONFIG_TASK_XACCT)
1308 	u64 acct_rss_mem1;	/* accumulated rss usage */
1309 	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1310 	cputime_t acct_timexpd;	/* stime + utime since last update */
1311 #endif
1312 #ifdef CONFIG_CPUSETS
1313 	nodemask_t mems_allowed;	/* Protected by alloc_lock */
1314 	seqcount_t mems_allowed_seq;	/* Seqence no to catch updates */
1315 	int cpuset_mem_spread_rotor;
1316 	int cpuset_slab_spread_rotor;
1317 #endif
1318 #ifdef CONFIG_CGROUPS
1319 	/* Control Group info protected by css_set_lock */
1320 	struct css_set __rcu *cgroups;
1321 	/* cg_list protected by css_set_lock and tsk->alloc_lock */
1322 	struct list_head cg_list;
1323 #endif
1324 #ifdef CONFIG_FUTEX
1325 	struct robust_list_head __user *robust_list;
1326 #ifdef CONFIG_COMPAT
1327 	struct compat_robust_list_head __user *compat_robust_list;
1328 #endif
1329 	struct list_head pi_state_list;
1330 	struct futex_pi_state *pi_state_cache;
1331 #endif
1332 #ifdef CONFIG_PERF_EVENTS
1333 	struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1334 	struct mutex perf_event_mutex;
1335 	struct list_head perf_event_list;
1336 #endif
1337 #ifdef CONFIG_NUMA
1338 	struct mempolicy *mempolicy;	/* Protected by alloc_lock */
1339 	short il_next;
1340 	short pref_node_fork;
1341 #endif
1342 #ifdef CONFIG_NUMA_BALANCING
1343 	int numa_scan_seq;
1344 	unsigned int numa_scan_period;
1345 	unsigned int numa_scan_period_max;
1346 	int numa_preferred_nid;
1347 	int numa_migrate_deferred;
1348 	unsigned long numa_migrate_retry;
1349 	u64 node_stamp;			/* migration stamp  */
1350 	struct callback_head numa_work;
1351 
1352 	struct list_head numa_entry;
1353 	struct numa_group *numa_group;
1354 
1355 	/*
1356 	 * Exponential decaying average of faults on a per-node basis.
1357 	 * Scheduling placement decisions are made based on the these counts.
1358 	 * The values remain static for the duration of a PTE scan
1359 	 */
1360 	unsigned long *numa_faults;
1361 	unsigned long total_numa_faults;
1362 
1363 	/*
1364 	 * numa_faults_buffer records faults per node during the current
1365 	 * scan window. When the scan completes, the counts in numa_faults
1366 	 * decay and these values are copied.
1367 	 */
1368 	unsigned long *numa_faults_buffer;
1369 
1370 	/*
1371 	 * numa_faults_locality tracks if faults recorded during the last
1372 	 * scan window were remote/local. The task scan period is adapted
1373 	 * based on the locality of the faults with different weights
1374 	 * depending on whether they were shared or private faults
1375 	 */
1376 	unsigned long numa_faults_locality[2];
1377 
1378 	unsigned long numa_pages_migrated;
1379 #endif /* CONFIG_NUMA_BALANCING */
1380 
1381 	struct rcu_head rcu;
1382 
1383 	/*
1384 	 * cache last used pipe for splice
1385 	 */
1386 	struct pipe_inode_info *splice_pipe;
1387 
1388 	struct page_frag task_frag;
1389 
1390 #ifdef	CONFIG_TASK_DELAY_ACCT
1391 	struct task_delay_info *delays;
1392 #endif
1393 #ifdef CONFIG_FAULT_INJECTION
1394 	int make_it_fail;
1395 #endif
1396 	/*
1397 	 * when (nr_dirtied >= nr_dirtied_pause), it's time to call
1398 	 * balance_dirty_pages() for some dirty throttling pause
1399 	 */
1400 	int nr_dirtied;
1401 	int nr_dirtied_pause;
1402 	unsigned long dirty_paused_when; /* start of a write-and-pause period */
1403 
1404 #ifdef CONFIG_LATENCYTOP
1405 	int latency_record_count;
1406 	struct latency_record latency_record[LT_SAVECOUNT];
1407 #endif
1408 	/*
1409 	 * time slack values; these are used to round up poll() and
1410 	 * select() etc timeout values. These are in nanoseconds.
1411 	 */
1412 	unsigned long timer_slack_ns;
1413 	unsigned long default_timer_slack_ns;
1414 
1415 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1416 	/* Index of current stored address in ret_stack */
1417 	int curr_ret_stack;
1418 	/* Stack of return addresses for return function tracing */
1419 	struct ftrace_ret_stack	*ret_stack;
1420 	/* time stamp for last schedule */
1421 	unsigned long long ftrace_timestamp;
1422 	/*
1423 	 * Number of functions that haven't been traced
1424 	 * because of depth overrun.
1425 	 */
1426 	atomic_t trace_overrun;
1427 	/* Pause for the tracing */
1428 	atomic_t tracing_graph_pause;
1429 #endif
1430 #ifdef CONFIG_TRACING
1431 	/* state flags for use by tracers */
1432 	unsigned long trace;
1433 	/* bitmask and counter of trace recursion */
1434 	unsigned long trace_recursion;
1435 #endif /* CONFIG_TRACING */
1436 #ifdef CONFIG_MEMCG /* memcg uses this to do batch job */
1437 	struct memcg_batch_info {
1438 		int do_batch;	/* incremented when batch uncharge started */
1439 		struct mem_cgroup *memcg; /* target memcg of uncharge */
1440 		unsigned long nr_pages;	/* uncharged usage */
1441 		unsigned long memsw_nr_pages; /* uncharged mem+swap usage */
1442 	} memcg_batch;
1443 	unsigned int memcg_kmem_skip_account;
1444 	struct memcg_oom_info {
1445 		struct mem_cgroup *memcg;
1446 		gfp_t gfp_mask;
1447 		int order;
1448 		unsigned int may_oom:1;
1449 	} memcg_oom;
1450 #endif
1451 #ifdef CONFIG_UPROBES
1452 	struct uprobe_task *utask;
1453 #endif
1454 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1455 	unsigned int	sequential_io;
1456 	unsigned int	sequential_io_avg;
1457 #endif
1458 };
1459 
1460 /* Future-safe accessor for struct task_struct's cpus_allowed. */
1461 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1462 
1463 #define TNF_MIGRATED	0x01
1464 #define TNF_NO_GROUP	0x02
1465 #define TNF_SHARED	0x04
1466 #define TNF_FAULT_LOCAL	0x08
1467 
1468 #ifdef CONFIG_NUMA_BALANCING
1469 extern void task_numa_fault(int last_node, int node, int pages, int flags);
1470 extern pid_t task_numa_group_id(struct task_struct *p);
1471 extern void set_numabalancing_state(bool enabled);
1472 extern void task_numa_free(struct task_struct *p);
1473 
1474 extern unsigned int sysctl_numa_balancing_migrate_deferred;
1475 #else
1476 static inline void task_numa_fault(int last_node, int node, int pages,
1477 				   int flags)
1478 {
1479 }
1480 static inline pid_t task_numa_group_id(struct task_struct *p)
1481 {
1482 	return 0;
1483 }
1484 static inline void set_numabalancing_state(bool enabled)
1485 {
1486 }
1487 static inline void task_numa_free(struct task_struct *p)
1488 {
1489 }
1490 #endif
1491 
1492 static inline struct pid *task_pid(struct task_struct *task)
1493 {
1494 	return task->pids[PIDTYPE_PID].pid;
1495 }
1496 
1497 static inline struct pid *task_tgid(struct task_struct *task)
1498 {
1499 	return task->group_leader->pids[PIDTYPE_PID].pid;
1500 }
1501 
1502 /*
1503  * Without tasklist or rcu lock it is not safe to dereference
1504  * the result of task_pgrp/task_session even if task == current,
1505  * we can race with another thread doing sys_setsid/sys_setpgid.
1506  */
1507 static inline struct pid *task_pgrp(struct task_struct *task)
1508 {
1509 	return task->group_leader->pids[PIDTYPE_PGID].pid;
1510 }
1511 
1512 static inline struct pid *task_session(struct task_struct *task)
1513 {
1514 	return task->group_leader->pids[PIDTYPE_SID].pid;
1515 }
1516 
1517 struct pid_namespace;
1518 
1519 /*
1520  * the helpers to get the task's different pids as they are seen
1521  * from various namespaces
1522  *
1523  * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1524  * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1525  *                     current.
1526  * task_xid_nr_ns()  : id seen from the ns specified;
1527  *
1528  * set_task_vxid()   : assigns a virtual id to a task;
1529  *
1530  * see also pid_nr() etc in include/linux/pid.h
1531  */
1532 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1533 			struct pid_namespace *ns);
1534 
1535 static inline pid_t task_pid_nr(struct task_struct *tsk)
1536 {
1537 	return tsk->pid;
1538 }
1539 
1540 static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1541 					struct pid_namespace *ns)
1542 {
1543 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1544 }
1545 
1546 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1547 {
1548 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1549 }
1550 
1551 
1552 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1553 {
1554 	return tsk->tgid;
1555 }
1556 
1557 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1558 
1559 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1560 {
1561 	return pid_vnr(task_tgid(tsk));
1562 }
1563 
1564 
1565 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1566 					struct pid_namespace *ns)
1567 {
1568 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1569 }
1570 
1571 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1572 {
1573 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1574 }
1575 
1576 
1577 static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1578 					struct pid_namespace *ns)
1579 {
1580 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1581 }
1582 
1583 static inline pid_t task_session_vnr(struct task_struct *tsk)
1584 {
1585 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1586 }
1587 
1588 /* obsolete, do not use */
1589 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1590 {
1591 	return task_pgrp_nr_ns(tsk, &init_pid_ns);
1592 }
1593 
1594 /**
1595  * pid_alive - check that a task structure is not stale
1596  * @p: Task structure to be checked.
1597  *
1598  * Test if a process is not yet dead (at most zombie state)
1599  * If pid_alive fails, then pointers within the task structure
1600  * can be stale and must not be dereferenced.
1601  *
1602  * Return: 1 if the process is alive. 0 otherwise.
1603  */
1604 static inline int pid_alive(struct task_struct *p)
1605 {
1606 	return p->pids[PIDTYPE_PID].pid != NULL;
1607 }
1608 
1609 /**
1610  * is_global_init - check if a task structure is init
1611  * @tsk: Task structure to be checked.
1612  *
1613  * Check if a task structure is the first user space task the kernel created.
1614  *
1615  * Return: 1 if the task structure is init. 0 otherwise.
1616  */
1617 static inline int is_global_init(struct task_struct *tsk)
1618 {
1619 	return tsk->pid == 1;
1620 }
1621 
1622 extern struct pid *cad_pid;
1623 
1624 extern void free_task(struct task_struct *tsk);
1625 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1626 
1627 extern void __put_task_struct(struct task_struct *t);
1628 
1629 static inline void put_task_struct(struct task_struct *t)
1630 {
1631 	if (atomic_dec_and_test(&t->usage))
1632 		__put_task_struct(t);
1633 }
1634 
1635 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1636 extern void task_cputime(struct task_struct *t,
1637 			 cputime_t *utime, cputime_t *stime);
1638 extern void task_cputime_scaled(struct task_struct *t,
1639 				cputime_t *utimescaled, cputime_t *stimescaled);
1640 extern cputime_t task_gtime(struct task_struct *t);
1641 #else
1642 static inline void task_cputime(struct task_struct *t,
1643 				cputime_t *utime, cputime_t *stime)
1644 {
1645 	if (utime)
1646 		*utime = t->utime;
1647 	if (stime)
1648 		*stime = t->stime;
1649 }
1650 
1651 static inline void task_cputime_scaled(struct task_struct *t,
1652 				       cputime_t *utimescaled,
1653 				       cputime_t *stimescaled)
1654 {
1655 	if (utimescaled)
1656 		*utimescaled = t->utimescaled;
1657 	if (stimescaled)
1658 		*stimescaled = t->stimescaled;
1659 }
1660 
1661 static inline cputime_t task_gtime(struct task_struct *t)
1662 {
1663 	return t->gtime;
1664 }
1665 #endif
1666 extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
1667 extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
1668 
1669 /*
1670  * Per process flags
1671  */
1672 #define PF_EXITING	0x00000004	/* getting shut down */
1673 #define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
1674 #define PF_VCPU		0x00000010	/* I'm a virtual CPU */
1675 #define PF_WQ_WORKER	0x00000020	/* I'm a workqueue worker */
1676 #define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
1677 #define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
1678 #define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
1679 #define PF_DUMPCORE	0x00000200	/* dumped core */
1680 #define PF_SIGNALED	0x00000400	/* killed by a signal */
1681 #define PF_MEMALLOC	0x00000800	/* Allocating memory */
1682 #define PF_NPROC_EXCEEDED 0x00001000	/* set_user noticed that RLIMIT_NPROC was exceeded */
1683 #define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
1684 #define PF_USED_ASYNC	0x00004000	/* used async_schedule*(), used by module init */
1685 #define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
1686 #define PF_FROZEN	0x00010000	/* frozen for system suspend */
1687 #define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
1688 #define PF_KSWAPD	0x00040000	/* I am kswapd */
1689 #define PF_MEMALLOC_NOIO 0x00080000	/* Allocating memory without IO involved */
1690 #define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
1691 #define PF_KTHREAD	0x00200000	/* I am a kernel thread */
1692 #define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
1693 #define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
1694 #define PF_SPREAD_PAGE	0x01000000	/* Spread page cache over cpuset */
1695 #define PF_SPREAD_SLAB	0x02000000	/* Spread some slab caches over cpuset */
1696 #define PF_NO_SETAFFINITY 0x04000000	/* Userland is not allowed to meddle with cpus_allowed */
1697 #define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
1698 #define PF_MEMPOLICY	0x10000000	/* Non-default NUMA mempolicy */
1699 #define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
1700 #define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezable */
1701 #define PF_SUSPEND_TASK 0x80000000      /* this thread called freeze_processes and should not be frozen */
1702 
1703 /*
1704  * Only the _current_ task can read/write to tsk->flags, but other
1705  * tasks can access tsk->flags in readonly mode for example
1706  * with tsk_used_math (like during threaded core dumping).
1707  * There is however an exception to this rule during ptrace
1708  * or during fork: the ptracer task is allowed to write to the
1709  * child->flags of its traced child (same goes for fork, the parent
1710  * can write to the child->flags), because we're guaranteed the
1711  * child is not running and in turn not changing child->flags
1712  * at the same time the parent does it.
1713  */
1714 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1715 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1716 #define clear_used_math() clear_stopped_child_used_math(current)
1717 #define set_used_math() set_stopped_child_used_math(current)
1718 #define conditional_stopped_child_used_math(condition, child) \
1719 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1720 #define conditional_used_math(condition) \
1721 	conditional_stopped_child_used_math(condition, current)
1722 #define copy_to_stopped_child_used_math(child) \
1723 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1724 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1725 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1726 #define used_math() tsk_used_math(current)
1727 
1728 /* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags */
1729 static inline gfp_t memalloc_noio_flags(gfp_t flags)
1730 {
1731 	if (unlikely(current->flags & PF_MEMALLOC_NOIO))
1732 		flags &= ~__GFP_IO;
1733 	return flags;
1734 }
1735 
1736 static inline unsigned int memalloc_noio_save(void)
1737 {
1738 	unsigned int flags = current->flags & PF_MEMALLOC_NOIO;
1739 	current->flags |= PF_MEMALLOC_NOIO;
1740 	return flags;
1741 }
1742 
1743 static inline void memalloc_noio_restore(unsigned int flags)
1744 {
1745 	current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags;
1746 }
1747 
1748 /*
1749  * task->jobctl flags
1750  */
1751 #define JOBCTL_STOP_SIGMASK	0xffff	/* signr of the last group stop */
1752 
1753 #define JOBCTL_STOP_DEQUEUED_BIT 16	/* stop signal dequeued */
1754 #define JOBCTL_STOP_PENDING_BIT	17	/* task should stop for group stop */
1755 #define JOBCTL_STOP_CONSUME_BIT	18	/* consume group stop count */
1756 #define JOBCTL_TRAP_STOP_BIT	19	/* trap for STOP */
1757 #define JOBCTL_TRAP_NOTIFY_BIT	20	/* trap for NOTIFY */
1758 #define JOBCTL_TRAPPING_BIT	21	/* switching to TRACED */
1759 #define JOBCTL_LISTENING_BIT	22	/* ptracer is listening for events */
1760 
1761 #define JOBCTL_STOP_DEQUEUED	(1 << JOBCTL_STOP_DEQUEUED_BIT)
1762 #define JOBCTL_STOP_PENDING	(1 << JOBCTL_STOP_PENDING_BIT)
1763 #define JOBCTL_STOP_CONSUME	(1 << JOBCTL_STOP_CONSUME_BIT)
1764 #define JOBCTL_TRAP_STOP	(1 << JOBCTL_TRAP_STOP_BIT)
1765 #define JOBCTL_TRAP_NOTIFY	(1 << JOBCTL_TRAP_NOTIFY_BIT)
1766 #define JOBCTL_TRAPPING		(1 << JOBCTL_TRAPPING_BIT)
1767 #define JOBCTL_LISTENING	(1 << JOBCTL_LISTENING_BIT)
1768 
1769 #define JOBCTL_TRAP_MASK	(JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY)
1770 #define JOBCTL_PENDING_MASK	(JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK)
1771 
1772 extern bool task_set_jobctl_pending(struct task_struct *task,
1773 				    unsigned int mask);
1774 extern void task_clear_jobctl_trapping(struct task_struct *task);
1775 extern void task_clear_jobctl_pending(struct task_struct *task,
1776 				      unsigned int mask);
1777 
1778 #ifdef CONFIG_PREEMPT_RCU
1779 
1780 #define RCU_READ_UNLOCK_BLOCKED (1 << 0) /* blocked while in RCU read-side. */
1781 #define RCU_READ_UNLOCK_NEED_QS (1 << 1) /* RCU core needs CPU response. */
1782 
1783 static inline void rcu_copy_process(struct task_struct *p)
1784 {
1785 	p->rcu_read_lock_nesting = 0;
1786 	p->rcu_read_unlock_special = 0;
1787 #ifdef CONFIG_TREE_PREEMPT_RCU
1788 	p->rcu_blocked_node = NULL;
1789 #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
1790 #ifdef CONFIG_RCU_BOOST
1791 	p->rcu_boost_mutex = NULL;
1792 #endif /* #ifdef CONFIG_RCU_BOOST */
1793 	INIT_LIST_HEAD(&p->rcu_node_entry);
1794 }
1795 
1796 #else
1797 
1798 static inline void rcu_copy_process(struct task_struct *p)
1799 {
1800 }
1801 
1802 #endif
1803 
1804 static inline void tsk_restore_flags(struct task_struct *task,
1805 				unsigned long orig_flags, unsigned long flags)
1806 {
1807 	task->flags &= ~flags;
1808 	task->flags |= orig_flags & flags;
1809 }
1810 
1811 #ifdef CONFIG_SMP
1812 extern void do_set_cpus_allowed(struct task_struct *p,
1813 			       const struct cpumask *new_mask);
1814 
1815 extern int set_cpus_allowed_ptr(struct task_struct *p,
1816 				const struct cpumask *new_mask);
1817 #else
1818 static inline void do_set_cpus_allowed(struct task_struct *p,
1819 				      const struct cpumask *new_mask)
1820 {
1821 }
1822 static inline int set_cpus_allowed_ptr(struct task_struct *p,
1823 				       const struct cpumask *new_mask)
1824 {
1825 	if (!cpumask_test_cpu(0, new_mask))
1826 		return -EINVAL;
1827 	return 0;
1828 }
1829 #endif
1830 
1831 #ifdef CONFIG_NO_HZ_COMMON
1832 void calc_load_enter_idle(void);
1833 void calc_load_exit_idle(void);
1834 #else
1835 static inline void calc_load_enter_idle(void) { }
1836 static inline void calc_load_exit_idle(void) { }
1837 #endif /* CONFIG_NO_HZ_COMMON */
1838 
1839 #ifndef CONFIG_CPUMASK_OFFSTACK
1840 static inline int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask)
1841 {
1842 	return set_cpus_allowed_ptr(p, &new_mask);
1843 }
1844 #endif
1845 
1846 /*
1847  * Do not use outside of architecture code which knows its limitations.
1848  *
1849  * sched_clock() has no promise of monotonicity or bounded drift between
1850  * CPUs, use (which you should not) requires disabling IRQs.
1851  *
1852  * Please use one of the three interfaces below.
1853  */
1854 extern unsigned long long notrace sched_clock(void);
1855 /*
1856  * See the comment in kernel/sched/clock.c
1857  */
1858 extern u64 cpu_clock(int cpu);
1859 extern u64 local_clock(void);
1860 extern u64 sched_clock_cpu(int cpu);
1861 
1862 
1863 extern void sched_clock_init(void);
1864 
1865 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1866 static inline void sched_clock_tick(void)
1867 {
1868 }
1869 
1870 static inline void sched_clock_idle_sleep_event(void)
1871 {
1872 }
1873 
1874 static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
1875 {
1876 }
1877 #else
1878 /*
1879  * Architectures can set this to 1 if they have specified
1880  * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
1881  * but then during bootup it turns out that sched_clock()
1882  * is reliable after all:
1883  */
1884 extern int sched_clock_stable;
1885 
1886 extern void sched_clock_tick(void);
1887 extern void sched_clock_idle_sleep_event(void);
1888 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1889 #endif
1890 
1891 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
1892 /*
1893  * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
1894  * The reason for this explicit opt-in is not to have perf penalty with
1895  * slow sched_clocks.
1896  */
1897 extern void enable_sched_clock_irqtime(void);
1898 extern void disable_sched_clock_irqtime(void);
1899 #else
1900 static inline void enable_sched_clock_irqtime(void) {}
1901 static inline void disable_sched_clock_irqtime(void) {}
1902 #endif
1903 
1904 extern unsigned long long
1905 task_sched_runtime(struct task_struct *task);
1906 
1907 /* sched_exec is called by processes performing an exec */
1908 #ifdef CONFIG_SMP
1909 extern void sched_exec(void);
1910 #else
1911 #define sched_exec()   {}
1912 #endif
1913 
1914 extern void sched_clock_idle_sleep_event(void);
1915 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
1916 
1917 #ifdef CONFIG_HOTPLUG_CPU
1918 extern void idle_task_exit(void);
1919 #else
1920 static inline void idle_task_exit(void) {}
1921 #endif
1922 
1923 #if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
1924 extern void wake_up_nohz_cpu(int cpu);
1925 #else
1926 static inline void wake_up_nohz_cpu(int cpu) { }
1927 #endif
1928 
1929 #ifdef CONFIG_NO_HZ_FULL
1930 extern bool sched_can_stop_tick(void);
1931 extern u64 scheduler_tick_max_deferment(void);
1932 #else
1933 static inline bool sched_can_stop_tick(void) { return false; }
1934 #endif
1935 
1936 #ifdef CONFIG_SCHED_AUTOGROUP
1937 extern void sched_autogroup_create_attach(struct task_struct *p);
1938 extern void sched_autogroup_detach(struct task_struct *p);
1939 extern void sched_autogroup_fork(struct signal_struct *sig);
1940 extern void sched_autogroup_exit(struct signal_struct *sig);
1941 #ifdef CONFIG_PROC_FS
1942 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
1943 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice);
1944 #endif
1945 #else
1946 static inline void sched_autogroup_create_attach(struct task_struct *p) { }
1947 static inline void sched_autogroup_detach(struct task_struct *p) { }
1948 static inline void sched_autogroup_fork(struct signal_struct *sig) { }
1949 static inline void sched_autogroup_exit(struct signal_struct *sig) { }
1950 #endif
1951 
1952 extern bool yield_to(struct task_struct *p, bool preempt);
1953 extern void set_user_nice(struct task_struct *p, long nice);
1954 extern int task_prio(const struct task_struct *p);
1955 extern int task_nice(const struct task_struct *p);
1956 extern int can_nice(const struct task_struct *p, const int nice);
1957 extern int task_curr(const struct task_struct *p);
1958 extern int idle_cpu(int cpu);
1959 extern int sched_setscheduler(struct task_struct *, int,
1960 			      const struct sched_param *);
1961 extern int sched_setscheduler_nocheck(struct task_struct *, int,
1962 				      const struct sched_param *);
1963 extern struct task_struct *idle_task(int cpu);
1964 /**
1965  * is_idle_task - is the specified task an idle task?
1966  * @p: the task in question.
1967  *
1968  * Return: 1 if @p is an idle task. 0 otherwise.
1969  */
1970 static inline bool is_idle_task(const struct task_struct *p)
1971 {
1972 	return p->pid == 0;
1973 }
1974 extern struct task_struct *curr_task(int cpu);
1975 extern void set_curr_task(int cpu, struct task_struct *p);
1976 
1977 void yield(void);
1978 
1979 /*
1980  * The default (Linux) execution domain.
1981  */
1982 extern struct exec_domain	default_exec_domain;
1983 
1984 union thread_union {
1985 	struct thread_info thread_info;
1986 	unsigned long stack[THREAD_SIZE/sizeof(long)];
1987 };
1988 
1989 #ifndef __HAVE_ARCH_KSTACK_END
1990 static inline int kstack_end(void *addr)
1991 {
1992 	/* Reliable end of stack detection:
1993 	 * Some APM bios versions misalign the stack
1994 	 */
1995 	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
1996 }
1997 #endif
1998 
1999 extern union thread_union init_thread_union;
2000 extern struct task_struct init_task;
2001 
2002 extern struct   mm_struct init_mm;
2003 
2004 extern struct pid_namespace init_pid_ns;
2005 
2006 /*
2007  * find a task by one of its numerical ids
2008  *
2009  * find_task_by_pid_ns():
2010  *      finds a task by its pid in the specified namespace
2011  * find_task_by_vpid():
2012  *      finds a task by its virtual pid
2013  *
2014  * see also find_vpid() etc in include/linux/pid.h
2015  */
2016 
2017 extern struct task_struct *find_task_by_vpid(pid_t nr);
2018 extern struct task_struct *find_task_by_pid_ns(pid_t nr,
2019 		struct pid_namespace *ns);
2020 
2021 /* per-UID process charging. */
2022 extern struct user_struct * alloc_uid(kuid_t);
2023 static inline struct user_struct *get_uid(struct user_struct *u)
2024 {
2025 	atomic_inc(&u->__count);
2026 	return u;
2027 }
2028 extern void free_uid(struct user_struct *);
2029 
2030 #include <asm/current.h>
2031 
2032 extern void xtime_update(unsigned long ticks);
2033 
2034 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2035 extern int wake_up_process(struct task_struct *tsk);
2036 extern void wake_up_new_task(struct task_struct *tsk);
2037 #ifdef CONFIG_SMP
2038  extern void kick_process(struct task_struct *tsk);
2039 #else
2040  static inline void kick_process(struct task_struct *tsk) { }
2041 #endif
2042 extern void sched_fork(unsigned long clone_flags, struct task_struct *p);
2043 extern void sched_dead(struct task_struct *p);
2044 
2045 extern void proc_caches_init(void);
2046 extern void flush_signals(struct task_struct *);
2047 extern void __flush_signals(struct task_struct *);
2048 extern void ignore_signals(struct task_struct *);
2049 extern void flush_signal_handlers(struct task_struct *, int force_default);
2050 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2051 
2052 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
2053 {
2054 	unsigned long flags;
2055 	int ret;
2056 
2057 	spin_lock_irqsave(&tsk->sighand->siglock, flags);
2058 	ret = dequeue_signal(tsk, mask, info);
2059 	spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
2060 
2061 	return ret;
2062 }
2063 
2064 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
2065 			      sigset_t *mask);
2066 extern void unblock_all_signals(void);
2067 extern void release_task(struct task_struct * p);
2068 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2069 extern int force_sigsegv(int, struct task_struct *);
2070 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2071 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2072 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2073 extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *,
2074 				const struct cred *, u32);
2075 extern int kill_pgrp(struct pid *pid, int sig, int priv);
2076 extern int kill_pid(struct pid *pid, int sig, int priv);
2077 extern int kill_proc_info(int, struct siginfo *, pid_t);
2078 extern __must_check bool do_notify_parent(struct task_struct *, int);
2079 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2080 extern void force_sig(int, struct task_struct *);
2081 extern int send_sig(int, struct task_struct *, int);
2082 extern int zap_other_threads(struct task_struct *p);
2083 extern struct sigqueue *sigqueue_alloc(void);
2084 extern void sigqueue_free(struct sigqueue *);
2085 extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
2086 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2087 
2088 static inline void restore_saved_sigmask(void)
2089 {
2090 	if (test_and_clear_restore_sigmask())
2091 		__set_current_blocked(&current->saved_sigmask);
2092 }
2093 
2094 static inline sigset_t *sigmask_to_save(void)
2095 {
2096 	sigset_t *res = &current->blocked;
2097 	if (unlikely(test_restore_sigmask()))
2098 		res = &current->saved_sigmask;
2099 	return res;
2100 }
2101 
2102 static inline int kill_cad_pid(int sig, int priv)
2103 {
2104 	return kill_pid(cad_pid, sig, priv);
2105 }
2106 
2107 /* These can be the second arg to send_sig_info/send_group_sig_info.  */
2108 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
2109 #define SEND_SIG_PRIV	((struct siginfo *) 1)
2110 #define SEND_SIG_FORCED	((struct siginfo *) 2)
2111 
2112 /*
2113  * True if we are on the alternate signal stack.
2114  */
2115 static inline int on_sig_stack(unsigned long sp)
2116 {
2117 #ifdef CONFIG_STACK_GROWSUP
2118 	return sp >= current->sas_ss_sp &&
2119 		sp - current->sas_ss_sp < current->sas_ss_size;
2120 #else
2121 	return sp > current->sas_ss_sp &&
2122 		sp - current->sas_ss_sp <= current->sas_ss_size;
2123 #endif
2124 }
2125 
2126 static inline int sas_ss_flags(unsigned long sp)
2127 {
2128 	return (current->sas_ss_size == 0 ? SS_DISABLE
2129 		: on_sig_stack(sp) ? SS_ONSTACK : 0);
2130 }
2131 
2132 static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig)
2133 {
2134 	if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp))
2135 #ifdef CONFIG_STACK_GROWSUP
2136 		return current->sas_ss_sp;
2137 #else
2138 		return current->sas_ss_sp + current->sas_ss_size;
2139 #endif
2140 	return sp;
2141 }
2142 
2143 /*
2144  * Routines for handling mm_structs
2145  */
2146 extern struct mm_struct * mm_alloc(void);
2147 
2148 /* mmdrop drops the mm and the page tables */
2149 extern void __mmdrop(struct mm_struct *);
2150 static inline void mmdrop(struct mm_struct * mm)
2151 {
2152 	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2153 		__mmdrop(mm);
2154 }
2155 
2156 /* mmput gets rid of the mappings and all user-space */
2157 extern void mmput(struct mm_struct *);
2158 /* Grab a reference to a task's mm, if it is not already going away */
2159 extern struct mm_struct *get_task_mm(struct task_struct *task);
2160 /*
2161  * Grab a reference to a task's mm, if it is not already going away
2162  * and ptrace_may_access with the mode parameter passed to it
2163  * succeeds.
2164  */
2165 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode);
2166 /* Remove the current tasks stale references to the old mm_struct */
2167 extern void mm_release(struct task_struct *, struct mm_struct *);
2168 /* Allocate a new mm structure and copy contents from tsk->mm */
2169 extern struct mm_struct *dup_mm(struct task_struct *tsk);
2170 
2171 extern int copy_thread(unsigned long, unsigned long, unsigned long,
2172 			struct task_struct *);
2173 extern void flush_thread(void);
2174 extern void exit_thread(void);
2175 
2176 extern void exit_files(struct task_struct *);
2177 extern void __cleanup_sighand(struct sighand_struct *);
2178 
2179 extern void exit_itimers(struct signal_struct *);
2180 extern void flush_itimer_signals(void);
2181 
2182 extern void do_group_exit(int);
2183 
2184 extern int allow_signal(int);
2185 extern int disallow_signal(int);
2186 
2187 extern int do_execve(const char *,
2188 		     const char __user * const __user *,
2189 		     const char __user * const __user *);
2190 extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
2191 struct task_struct *fork_idle(int);
2192 extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
2193 
2194 extern void set_task_comm(struct task_struct *tsk, char *from);
2195 extern char *get_task_comm(char *to, struct task_struct *tsk);
2196 
2197 #ifdef CONFIG_SMP
2198 void scheduler_ipi(void);
2199 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2200 #else
2201 static inline void scheduler_ipi(void) { }
2202 static inline unsigned long wait_task_inactive(struct task_struct *p,
2203 					       long match_state)
2204 {
2205 	return 1;
2206 }
2207 #endif
2208 
2209 #define next_task(p) \
2210 	list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2211 
2212 #define for_each_process(p) \
2213 	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2214 
2215 extern bool current_is_single_threaded(void);
2216 
2217 /*
2218  * Careful: do_each_thread/while_each_thread is a double loop so
2219  *          'break' will not work as expected - use goto instead.
2220  */
2221 #define do_each_thread(g, t) \
2222 	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2223 
2224 #define while_each_thread(g, t) \
2225 	while ((t = next_thread(t)) != g)
2226 
2227 static inline int get_nr_threads(struct task_struct *tsk)
2228 {
2229 	return tsk->signal->nr_threads;
2230 }
2231 
2232 static inline bool thread_group_leader(struct task_struct *p)
2233 {
2234 	return p->exit_signal >= 0;
2235 }
2236 
2237 /* Do to the insanities of de_thread it is possible for a process
2238  * to have the pid of the thread group leader without actually being
2239  * the thread group leader.  For iteration through the pids in proc
2240  * all we care about is that we have a task with the appropriate
2241  * pid, we don't actually care if we have the right task.
2242  */
2243 static inline bool has_group_leader_pid(struct task_struct *p)
2244 {
2245 	return task_pid(p) == p->signal->leader_pid;
2246 }
2247 
2248 static inline
2249 bool same_thread_group(struct task_struct *p1, struct task_struct *p2)
2250 {
2251 	return p1->signal == p2->signal;
2252 }
2253 
2254 static inline struct task_struct *next_thread(const struct task_struct *p)
2255 {
2256 	return list_entry_rcu(p->thread_group.next,
2257 			      struct task_struct, thread_group);
2258 }
2259 
2260 static inline int thread_group_empty(struct task_struct *p)
2261 {
2262 	return list_empty(&p->thread_group);
2263 }
2264 
2265 #define delay_group_leader(p) \
2266 		(thread_group_leader(p) && !thread_group_empty(p))
2267 
2268 /*
2269  * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2270  * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2271  * pins the final release of task.io_context.  Also protects ->cpuset and
2272  * ->cgroup.subsys[]. And ->vfork_done.
2273  *
2274  * Nests both inside and outside of read_lock(&tasklist_lock).
2275  * It must not be nested with write_lock_irq(&tasklist_lock),
2276  * neither inside nor outside.
2277  */
2278 static inline void task_lock(struct task_struct *p)
2279 {
2280 	spin_lock(&p->alloc_lock);
2281 }
2282 
2283 static inline void task_unlock(struct task_struct *p)
2284 {
2285 	spin_unlock(&p->alloc_lock);
2286 }
2287 
2288 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2289 							unsigned long *flags);
2290 
2291 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2292 						       unsigned long *flags)
2293 {
2294 	struct sighand_struct *ret;
2295 
2296 	ret = __lock_task_sighand(tsk, flags);
2297 	(void)__cond_lock(&tsk->sighand->siglock, ret);
2298 	return ret;
2299 }
2300 
2301 static inline void unlock_task_sighand(struct task_struct *tsk,
2302 						unsigned long *flags)
2303 {
2304 	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2305 }
2306 
2307 #ifdef CONFIG_CGROUPS
2308 static inline void threadgroup_change_begin(struct task_struct *tsk)
2309 {
2310 	down_read(&tsk->signal->group_rwsem);
2311 }
2312 static inline void threadgroup_change_end(struct task_struct *tsk)
2313 {
2314 	up_read(&tsk->signal->group_rwsem);
2315 }
2316 
2317 /**
2318  * threadgroup_lock - lock threadgroup
2319  * @tsk: member task of the threadgroup to lock
2320  *
2321  * Lock the threadgroup @tsk belongs to.  No new task is allowed to enter
2322  * and member tasks aren't allowed to exit (as indicated by PF_EXITING) or
2323  * change ->group_leader/pid.  This is useful for cases where the threadgroup
2324  * needs to stay stable across blockable operations.
2325  *
2326  * fork and exit paths explicitly call threadgroup_change_{begin|end}() for
2327  * synchronization.  While held, no new task will be added to threadgroup
2328  * and no existing live task will have its PF_EXITING set.
2329  *
2330  * de_thread() does threadgroup_change_{begin|end}() when a non-leader
2331  * sub-thread becomes a new leader.
2332  */
2333 static inline void threadgroup_lock(struct task_struct *tsk)
2334 {
2335 	down_write(&tsk->signal->group_rwsem);
2336 }
2337 
2338 /**
2339  * threadgroup_unlock - unlock threadgroup
2340  * @tsk: member task of the threadgroup to unlock
2341  *
2342  * Reverse threadgroup_lock().
2343  */
2344 static inline void threadgroup_unlock(struct task_struct *tsk)
2345 {
2346 	up_write(&tsk->signal->group_rwsem);
2347 }
2348 #else
2349 static inline void threadgroup_change_begin(struct task_struct *tsk) {}
2350 static inline void threadgroup_change_end(struct task_struct *tsk) {}
2351 static inline void threadgroup_lock(struct task_struct *tsk) {}
2352 static inline void threadgroup_unlock(struct task_struct *tsk) {}
2353 #endif
2354 
2355 #ifndef __HAVE_THREAD_FUNCTIONS
2356 
2357 #define task_thread_info(task)	((struct thread_info *)(task)->stack)
2358 #define task_stack_page(task)	((task)->stack)
2359 
2360 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2361 {
2362 	*task_thread_info(p) = *task_thread_info(org);
2363 	task_thread_info(p)->task = p;
2364 }
2365 
2366 static inline unsigned long *end_of_stack(struct task_struct *p)
2367 {
2368 	return (unsigned long *)(task_thread_info(p) + 1);
2369 }
2370 
2371 #endif
2372 
2373 static inline int object_is_on_stack(void *obj)
2374 {
2375 	void *stack = task_stack_page(current);
2376 
2377 	return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2378 }
2379 
2380 extern void thread_info_cache_init(void);
2381 
2382 #ifdef CONFIG_DEBUG_STACK_USAGE
2383 static inline unsigned long stack_not_used(struct task_struct *p)
2384 {
2385 	unsigned long *n = end_of_stack(p);
2386 
2387 	do { 	/* Skip over canary */
2388 		n++;
2389 	} while (!*n);
2390 
2391 	return (unsigned long)n - (unsigned long)end_of_stack(p);
2392 }
2393 #endif
2394 
2395 /* set thread flags in other task's structures
2396  * - see asm/thread_info.h for TIF_xxxx flags available
2397  */
2398 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2399 {
2400 	set_ti_thread_flag(task_thread_info(tsk), flag);
2401 }
2402 
2403 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2404 {
2405 	clear_ti_thread_flag(task_thread_info(tsk), flag);
2406 }
2407 
2408 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2409 {
2410 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2411 }
2412 
2413 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2414 {
2415 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2416 }
2417 
2418 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2419 {
2420 	return test_ti_thread_flag(task_thread_info(tsk), flag);
2421 }
2422 
2423 static inline void set_tsk_need_resched(struct task_struct *tsk)
2424 {
2425 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2426 }
2427 
2428 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2429 {
2430 	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2431 }
2432 
2433 static inline int test_tsk_need_resched(struct task_struct *tsk)
2434 {
2435 	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2436 }
2437 
2438 static inline int restart_syscall(void)
2439 {
2440 	set_tsk_thread_flag(current, TIF_SIGPENDING);
2441 	return -ERESTARTNOINTR;
2442 }
2443 
2444 static inline int signal_pending(struct task_struct *p)
2445 {
2446 	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2447 }
2448 
2449 static inline int __fatal_signal_pending(struct task_struct *p)
2450 {
2451 	return unlikely(sigismember(&p->pending.signal, SIGKILL));
2452 }
2453 
2454 static inline int fatal_signal_pending(struct task_struct *p)
2455 {
2456 	return signal_pending(p) && __fatal_signal_pending(p);
2457 }
2458 
2459 static inline int signal_pending_state(long state, struct task_struct *p)
2460 {
2461 	if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2462 		return 0;
2463 	if (!signal_pending(p))
2464 		return 0;
2465 
2466 	return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2467 }
2468 
2469 /*
2470  * cond_resched() and cond_resched_lock(): latency reduction via
2471  * explicit rescheduling in places that are safe. The return
2472  * value indicates whether a reschedule was done in fact.
2473  * cond_resched_lock() will drop the spinlock before scheduling,
2474  * cond_resched_softirq() will enable bhs before scheduling.
2475  */
2476 extern int _cond_resched(void);
2477 
2478 #define cond_resched() ({			\
2479 	__might_sleep(__FILE__, __LINE__, 0);	\
2480 	_cond_resched();			\
2481 })
2482 
2483 extern int __cond_resched_lock(spinlock_t *lock);
2484 
2485 #ifdef CONFIG_PREEMPT_COUNT
2486 #define PREEMPT_LOCK_OFFSET	PREEMPT_OFFSET
2487 #else
2488 #define PREEMPT_LOCK_OFFSET	0
2489 #endif
2490 
2491 #define cond_resched_lock(lock) ({				\
2492 	__might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);	\
2493 	__cond_resched_lock(lock);				\
2494 })
2495 
2496 extern int __cond_resched_softirq(void);
2497 
2498 #define cond_resched_softirq() ({					\
2499 	__might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET);	\
2500 	__cond_resched_softirq();					\
2501 })
2502 
2503 static inline void cond_resched_rcu(void)
2504 {
2505 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
2506 	rcu_read_unlock();
2507 	cond_resched();
2508 	rcu_read_lock();
2509 #endif
2510 }
2511 
2512 /*
2513  * Does a critical section need to be broken due to another
2514  * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2515  * but a general need for low latency)
2516  */
2517 static inline int spin_needbreak(spinlock_t *lock)
2518 {
2519 #ifdef CONFIG_PREEMPT
2520 	return spin_is_contended(lock);
2521 #else
2522 	return 0;
2523 #endif
2524 }
2525 
2526 /*
2527  * Idle thread specific functions to determine the need_resched
2528  * polling state. We have two versions, one based on TS_POLLING in
2529  * thread_info.status and one based on TIF_POLLING_NRFLAG in
2530  * thread_info.flags
2531  */
2532 #ifdef TS_POLLING
2533 static inline int tsk_is_polling(struct task_struct *p)
2534 {
2535 	return task_thread_info(p)->status & TS_POLLING;
2536 }
2537 static inline void __current_set_polling(void)
2538 {
2539 	current_thread_info()->status |= TS_POLLING;
2540 }
2541 
2542 static inline bool __must_check current_set_polling_and_test(void)
2543 {
2544 	__current_set_polling();
2545 
2546 	/*
2547 	 * Polling state must be visible before we test NEED_RESCHED,
2548 	 * paired by resched_task()
2549 	 */
2550 	smp_mb();
2551 
2552 	return unlikely(tif_need_resched());
2553 }
2554 
2555 static inline void __current_clr_polling(void)
2556 {
2557 	current_thread_info()->status &= ~TS_POLLING;
2558 }
2559 
2560 static inline bool __must_check current_clr_polling_and_test(void)
2561 {
2562 	__current_clr_polling();
2563 
2564 	/*
2565 	 * Polling state must be visible before we test NEED_RESCHED,
2566 	 * paired by resched_task()
2567 	 */
2568 	smp_mb();
2569 
2570 	return unlikely(tif_need_resched());
2571 }
2572 #elif defined(TIF_POLLING_NRFLAG)
2573 static inline int tsk_is_polling(struct task_struct *p)
2574 {
2575 	return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG);
2576 }
2577 
2578 static inline void __current_set_polling(void)
2579 {
2580 	set_thread_flag(TIF_POLLING_NRFLAG);
2581 }
2582 
2583 static inline bool __must_check current_set_polling_and_test(void)
2584 {
2585 	__current_set_polling();
2586 
2587 	/*
2588 	 * Polling state must be visible before we test NEED_RESCHED,
2589 	 * paired by resched_task()
2590 	 *
2591 	 * XXX: assumes set/clear bit are identical barrier wise.
2592 	 */
2593 	smp_mb__after_clear_bit();
2594 
2595 	return unlikely(tif_need_resched());
2596 }
2597 
2598 static inline void __current_clr_polling(void)
2599 {
2600 	clear_thread_flag(TIF_POLLING_NRFLAG);
2601 }
2602 
2603 static inline bool __must_check current_clr_polling_and_test(void)
2604 {
2605 	__current_clr_polling();
2606 
2607 	/*
2608 	 * Polling state must be visible before we test NEED_RESCHED,
2609 	 * paired by resched_task()
2610 	 */
2611 	smp_mb__after_clear_bit();
2612 
2613 	return unlikely(tif_need_resched());
2614 }
2615 
2616 #else
2617 static inline int tsk_is_polling(struct task_struct *p) { return 0; }
2618 static inline void __current_set_polling(void) { }
2619 static inline void __current_clr_polling(void) { }
2620 
2621 static inline bool __must_check current_set_polling_and_test(void)
2622 {
2623 	return unlikely(tif_need_resched());
2624 }
2625 static inline bool __must_check current_clr_polling_and_test(void)
2626 {
2627 	return unlikely(tif_need_resched());
2628 }
2629 #endif
2630 
2631 static __always_inline bool need_resched(void)
2632 {
2633 	return unlikely(tif_need_resched());
2634 }
2635 
2636 /*
2637  * Thread group CPU time accounting.
2638  */
2639 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2640 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2641 
2642 static inline void thread_group_cputime_init(struct signal_struct *sig)
2643 {
2644 	raw_spin_lock_init(&sig->cputimer.lock);
2645 }
2646 
2647 /*
2648  * Reevaluate whether the task has signals pending delivery.
2649  * Wake the task if so.
2650  * This is required every time the blocked sigset_t changes.
2651  * callers must hold sighand->siglock.
2652  */
2653 extern void recalc_sigpending_and_wake(struct task_struct *t);
2654 extern void recalc_sigpending(void);
2655 
2656 extern void signal_wake_up_state(struct task_struct *t, unsigned int state);
2657 
2658 static inline void signal_wake_up(struct task_struct *t, bool resume)
2659 {
2660 	signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
2661 }
2662 static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
2663 {
2664 	signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
2665 }
2666 
2667 /*
2668  * Wrappers for p->thread_info->cpu access. No-op on UP.
2669  */
2670 #ifdef CONFIG_SMP
2671 
2672 static inline unsigned int task_cpu(const struct task_struct *p)
2673 {
2674 	return task_thread_info(p)->cpu;
2675 }
2676 
2677 static inline int task_node(const struct task_struct *p)
2678 {
2679 	return cpu_to_node(task_cpu(p));
2680 }
2681 
2682 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2683 
2684 #else
2685 
2686 static inline unsigned int task_cpu(const struct task_struct *p)
2687 {
2688 	return 0;
2689 }
2690 
2691 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2692 {
2693 }
2694 
2695 #endif /* CONFIG_SMP */
2696 
2697 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
2698 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
2699 
2700 #ifdef CONFIG_CGROUP_SCHED
2701 extern struct task_group root_task_group;
2702 #endif /* CONFIG_CGROUP_SCHED */
2703 
2704 extern int task_can_switch_user(struct user_struct *up,
2705 					struct task_struct *tsk);
2706 
2707 #ifdef CONFIG_TASK_XACCT
2708 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2709 {
2710 	tsk->ioac.rchar += amt;
2711 }
2712 
2713 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2714 {
2715 	tsk->ioac.wchar += amt;
2716 }
2717 
2718 static inline void inc_syscr(struct task_struct *tsk)
2719 {
2720 	tsk->ioac.syscr++;
2721 }
2722 
2723 static inline void inc_syscw(struct task_struct *tsk)
2724 {
2725 	tsk->ioac.syscw++;
2726 }
2727 #else
2728 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
2729 {
2730 }
2731 
2732 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
2733 {
2734 }
2735 
2736 static inline void inc_syscr(struct task_struct *tsk)
2737 {
2738 }
2739 
2740 static inline void inc_syscw(struct task_struct *tsk)
2741 {
2742 }
2743 #endif
2744 
2745 #ifndef TASK_SIZE_OF
2746 #define TASK_SIZE_OF(tsk)	TASK_SIZE
2747 #endif
2748 
2749 #ifdef CONFIG_MM_OWNER
2750 extern void mm_update_next_owner(struct mm_struct *mm);
2751 extern void mm_init_owner(struct mm_struct *mm, struct task_struct *p);
2752 #else
2753 static inline void mm_update_next_owner(struct mm_struct *mm)
2754 {
2755 }
2756 
2757 static inline void mm_init_owner(struct mm_struct *mm, struct task_struct *p)
2758 {
2759 }
2760 #endif /* CONFIG_MM_OWNER */
2761 
2762 static inline unsigned long task_rlimit(const struct task_struct *tsk,
2763 		unsigned int limit)
2764 {
2765 	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_cur);
2766 }
2767 
2768 static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
2769 		unsigned int limit)
2770 {
2771 	return ACCESS_ONCE(tsk->signal->rlim[limit].rlim_max);
2772 }
2773 
2774 static inline unsigned long rlimit(unsigned int limit)
2775 {
2776 	return task_rlimit(current, limit);
2777 }
2778 
2779 static inline unsigned long rlimit_max(unsigned int limit)
2780 {
2781 	return task_rlimit_max(current, limit);
2782 }
2783 
2784 #endif
2785