xref: /linux-6.15/include/linux/sched.h (revision 230ccb37)
1 #ifndef _LINUX_SCHED_H
2 #define _LINUX_SCHED_H
3 
4 #include <uapi/linux/sched.h>
5 
6 #include <linux/sched/prio.h>
7 
8 
9 struct sched_param {
10 	int sched_priority;
11 };
12 
13 #include <asm/param.h>	/* for HZ */
14 
15 #include <linux/capability.h>
16 #include <linux/threads.h>
17 #include <linux/kernel.h>
18 #include <linux/types.h>
19 #include <linux/timex.h>
20 #include <linux/jiffies.h>
21 #include <linux/plist.h>
22 #include <linux/rbtree.h>
23 #include <linux/thread_info.h>
24 #include <linux/cpumask.h>
25 #include <linux/errno.h>
26 #include <linux/nodemask.h>
27 #include <linux/mm_types.h>
28 #include <linux/preempt.h>
29 
30 #include <asm/page.h>
31 #include <asm/ptrace.h>
32 #include <linux/cputime.h>
33 
34 #include <linux/smp.h>
35 #include <linux/sem.h>
36 #include <linux/shm.h>
37 #include <linux/signal.h>
38 #include <linux/compiler.h>
39 #include <linux/completion.h>
40 #include <linux/pid.h>
41 #include <linux/percpu.h>
42 #include <linux/topology.h>
43 #include <linux/proportions.h>
44 #include <linux/seccomp.h>
45 #include <linux/rcupdate.h>
46 #include <linux/rculist.h>
47 #include <linux/rtmutex.h>
48 
49 #include <linux/time.h>
50 #include <linux/param.h>
51 #include <linux/resource.h>
52 #include <linux/timer.h>
53 #include <linux/hrtimer.h>
54 #include <linux/task_io_accounting.h>
55 #include <linux/latencytop.h>
56 #include <linux/cred.h>
57 #include <linux/llist.h>
58 #include <linux/uidgid.h>
59 #include <linux/gfp.h>
60 #include <linux/magic.h>
61 #include <linux/cgroup-defs.h>
62 
63 #include <asm/processor.h>
64 
65 #define SCHED_ATTR_SIZE_VER0	48	/* sizeof first published struct */
66 
67 /*
68  * Extended scheduling parameters data structure.
69  *
70  * This is needed because the original struct sched_param can not be
71  * altered without introducing ABI issues with legacy applications
72  * (e.g., in sched_getparam()).
73  *
74  * However, the possibility of specifying more than just a priority for
75  * the tasks may be useful for a wide variety of application fields, e.g.,
76  * multimedia, streaming, automation and control, and many others.
77  *
78  * This variant (sched_attr) is meant at describing a so-called
79  * sporadic time-constrained task. In such model a task is specified by:
80  *  - the activation period or minimum instance inter-arrival time;
81  *  - the maximum (or average, depending on the actual scheduling
82  *    discipline) computation time of all instances, a.k.a. runtime;
83  *  - the deadline (relative to the actual activation time) of each
84  *    instance.
85  * Very briefly, a periodic (sporadic) task asks for the execution of
86  * some specific computation --which is typically called an instance--
87  * (at most) every period. Moreover, each instance typically lasts no more
88  * than the runtime and must be completed by time instant t equal to
89  * the instance activation time + the deadline.
90  *
91  * This is reflected by the actual fields of the sched_attr structure:
92  *
93  *  @size		size of the structure, for fwd/bwd compat.
94  *
95  *  @sched_policy	task's scheduling policy
96  *  @sched_flags	for customizing the scheduler behaviour
97  *  @sched_nice		task's nice value      (SCHED_NORMAL/BATCH)
98  *  @sched_priority	task's static priority (SCHED_FIFO/RR)
99  *  @sched_deadline	representative of the task's deadline
100  *  @sched_runtime	representative of the task's runtime
101  *  @sched_period	representative of the task's period
102  *
103  * Given this task model, there are a multiplicity of scheduling algorithms
104  * and policies, that can be used to ensure all the tasks will make their
105  * timing constraints.
106  *
107  * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the
108  * only user of this new interface. More information about the algorithm
109  * available in the scheduling class file or in Documentation/.
110  */
111 struct sched_attr {
112 	u32 size;
113 
114 	u32 sched_policy;
115 	u64 sched_flags;
116 
117 	/* SCHED_NORMAL, SCHED_BATCH */
118 	s32 sched_nice;
119 
120 	/* SCHED_FIFO, SCHED_RR */
121 	u32 sched_priority;
122 
123 	/* SCHED_DEADLINE */
124 	u64 sched_runtime;
125 	u64 sched_deadline;
126 	u64 sched_period;
127 };
128 
129 struct futex_pi_state;
130 struct robust_list_head;
131 struct bio_list;
132 struct fs_struct;
133 struct perf_event_context;
134 struct blk_plug;
135 struct filename;
136 struct nameidata;
137 
138 #define VMACACHE_BITS 2
139 #define VMACACHE_SIZE (1U << VMACACHE_BITS)
140 #define VMACACHE_MASK (VMACACHE_SIZE - 1)
141 
142 /*
143  * These are the constant used to fake the fixed-point load-average
144  * counting. Some notes:
145  *  - 11 bit fractions expand to 22 bits by the multiplies: this gives
146  *    a load-average precision of 10 bits integer + 11 bits fractional
147  *  - if you want to count load-averages more often, you need more
148  *    precision, or rounding will get you. With 2-second counting freq,
149  *    the EXP_n values would be 1981, 2034 and 2043 if still using only
150  *    11 bit fractions.
151  */
152 extern unsigned long avenrun[];		/* Load averages */
153 extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
154 
155 #define FSHIFT		11		/* nr of bits of precision */
156 #define FIXED_1		(1<<FSHIFT)	/* 1.0 as fixed-point */
157 #define LOAD_FREQ	(5*HZ+1)	/* 5 sec intervals */
158 #define EXP_1		1884		/* 1/exp(5sec/1min) as fixed-point */
159 #define EXP_5		2014		/* 1/exp(5sec/5min) */
160 #define EXP_15		2037		/* 1/exp(5sec/15min) */
161 
162 #define CALC_LOAD(load,exp,n) \
163 	load *= exp; \
164 	load += n*(FIXED_1-exp); \
165 	load >>= FSHIFT;
166 
167 extern unsigned long total_forks;
168 extern int nr_threads;
169 DECLARE_PER_CPU(unsigned long, process_counts);
170 extern int nr_processes(void);
171 extern unsigned long nr_running(void);
172 extern bool single_task_running(void);
173 extern unsigned long nr_iowait(void);
174 extern unsigned long nr_iowait_cpu(int cpu);
175 extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load);
176 
177 extern void calc_global_load(unsigned long ticks);
178 
179 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
180 extern void update_cpu_load_nohz(void);
181 #else
182 static inline void update_cpu_load_nohz(void) { }
183 #endif
184 
185 extern unsigned long get_parent_ip(unsigned long addr);
186 
187 extern void dump_cpu_task(int cpu);
188 
189 struct seq_file;
190 struct cfs_rq;
191 struct task_group;
192 #ifdef CONFIG_SCHED_DEBUG
193 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
194 extern void proc_sched_set_task(struct task_struct *p);
195 #endif
196 
197 /*
198  * Task state bitmask. NOTE! These bits are also
199  * encoded in fs/proc/array.c: get_task_state().
200  *
201  * We have two separate sets of flags: task->state
202  * is about runnability, while task->exit_state are
203  * about the task exiting. Confusing, but this way
204  * modifying one set can't modify the other one by
205  * mistake.
206  */
207 #define TASK_RUNNING		0
208 #define TASK_INTERRUPTIBLE	1
209 #define TASK_UNINTERRUPTIBLE	2
210 #define __TASK_STOPPED		4
211 #define __TASK_TRACED		8
212 /* in tsk->exit_state */
213 #define EXIT_DEAD		16
214 #define EXIT_ZOMBIE		32
215 #define EXIT_TRACE		(EXIT_ZOMBIE | EXIT_DEAD)
216 /* in tsk->state again */
217 #define TASK_DEAD		64
218 #define TASK_WAKEKILL		128
219 #define TASK_WAKING		256
220 #define TASK_PARKED		512
221 #define TASK_NOLOAD		1024
222 #define TASK_STATE_MAX		2048
223 
224 #define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPN"
225 
226 extern char ___assert_task_state[1 - 2*!!(
227 		sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
228 
229 /* Convenience macros for the sake of set_task_state */
230 #define TASK_KILLABLE		(TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
231 #define TASK_STOPPED		(TASK_WAKEKILL | __TASK_STOPPED)
232 #define TASK_TRACED		(TASK_WAKEKILL | __TASK_TRACED)
233 
234 #define TASK_IDLE		(TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
235 
236 /* Convenience macros for the sake of wake_up */
237 #define TASK_NORMAL		(TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
238 #define TASK_ALL		(TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
239 
240 /* get_task_state() */
241 #define TASK_REPORT		(TASK_RUNNING | TASK_INTERRUPTIBLE | \
242 				 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
243 				 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD)
244 
245 #define task_is_traced(task)	((task->state & __TASK_TRACED) != 0)
246 #define task_is_stopped(task)	((task->state & __TASK_STOPPED) != 0)
247 #define task_is_stopped_or_traced(task)	\
248 			((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
249 #define task_contributes_to_load(task)	\
250 				((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
251 				 (task->flags & PF_FROZEN) == 0 && \
252 				 (task->state & TASK_NOLOAD) == 0)
253 
254 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
255 
256 #define __set_task_state(tsk, state_value)			\
257 	do {							\
258 		(tsk)->task_state_change = _THIS_IP_;		\
259 		(tsk)->state = (state_value);			\
260 	} while (0)
261 #define set_task_state(tsk, state_value)			\
262 	do {							\
263 		(tsk)->task_state_change = _THIS_IP_;		\
264 		smp_store_mb((tsk)->state, (state_value));		\
265 	} while (0)
266 
267 /*
268  * set_current_state() includes a barrier so that the write of current->state
269  * is correctly serialised wrt the caller's subsequent test of whether to
270  * actually sleep:
271  *
272  *	set_current_state(TASK_UNINTERRUPTIBLE);
273  *	if (do_i_need_to_sleep())
274  *		schedule();
275  *
276  * If the caller does not need such serialisation then use __set_current_state()
277  */
278 #define __set_current_state(state_value)			\
279 	do {							\
280 		current->task_state_change = _THIS_IP_;		\
281 		current->state = (state_value);			\
282 	} while (0)
283 #define set_current_state(state_value)				\
284 	do {							\
285 		current->task_state_change = _THIS_IP_;		\
286 		smp_store_mb(current->state, (state_value));		\
287 	} while (0)
288 
289 #else
290 
291 #define __set_task_state(tsk, state_value)		\
292 	do { (tsk)->state = (state_value); } while (0)
293 #define set_task_state(tsk, state_value)		\
294 	smp_store_mb((tsk)->state, (state_value))
295 
296 /*
297  * set_current_state() includes a barrier so that the write of current->state
298  * is correctly serialised wrt the caller's subsequent test of whether to
299  * actually sleep:
300  *
301  *	set_current_state(TASK_UNINTERRUPTIBLE);
302  *	if (do_i_need_to_sleep())
303  *		schedule();
304  *
305  * If the caller does not need such serialisation then use __set_current_state()
306  */
307 #define __set_current_state(state_value)		\
308 	do { current->state = (state_value); } while (0)
309 #define set_current_state(state_value)			\
310 	smp_store_mb(current->state, (state_value))
311 
312 #endif
313 
314 /* Task command name length */
315 #define TASK_COMM_LEN 16
316 
317 #include <linux/spinlock.h>
318 
319 /*
320  * This serializes "schedule()" and also protects
321  * the run-queue from deletions/modifications (but
322  * _adding_ to the beginning of the run-queue has
323  * a separate lock).
324  */
325 extern rwlock_t tasklist_lock;
326 extern spinlock_t mmlist_lock;
327 
328 struct task_struct;
329 
330 #ifdef CONFIG_PROVE_RCU
331 extern int lockdep_tasklist_lock_is_held(void);
332 #endif /* #ifdef CONFIG_PROVE_RCU */
333 
334 extern void sched_init(void);
335 extern void sched_init_smp(void);
336 extern asmlinkage void schedule_tail(struct task_struct *prev);
337 extern void init_idle(struct task_struct *idle, int cpu);
338 extern void init_idle_bootup_task(struct task_struct *idle);
339 
340 extern cpumask_var_t cpu_isolated_map;
341 
342 extern int runqueue_is_locked(int cpu);
343 
344 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
345 extern void nohz_balance_enter_idle(int cpu);
346 extern void set_cpu_sd_state_idle(void);
347 extern int get_nohz_timer_target(void);
348 #else
349 static inline void nohz_balance_enter_idle(int cpu) { }
350 static inline void set_cpu_sd_state_idle(void) { }
351 #endif
352 
353 /*
354  * Only dump TASK_* tasks. (0 for all tasks)
355  */
356 extern void show_state_filter(unsigned long state_filter);
357 
358 static inline void show_state(void)
359 {
360 	show_state_filter(0);
361 }
362 
363 extern void show_regs(struct pt_regs *);
364 
365 /*
366  * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
367  * task), SP is the stack pointer of the first frame that should be shown in the back
368  * trace (or NULL if the entire call-chain of the task should be shown).
369  */
370 extern void show_stack(struct task_struct *task, unsigned long *sp);
371 
372 extern void cpu_init (void);
373 extern void trap_init(void);
374 extern void update_process_times(int user);
375 extern void scheduler_tick(void);
376 
377 extern void sched_show_task(struct task_struct *p);
378 
379 #ifdef CONFIG_LOCKUP_DETECTOR
380 extern void touch_softlockup_watchdog(void);
381 extern void touch_softlockup_watchdog_sync(void);
382 extern void touch_all_softlockup_watchdogs(void);
383 extern int proc_dowatchdog_thresh(struct ctl_table *table, int write,
384 				  void __user *buffer,
385 				  size_t *lenp, loff_t *ppos);
386 extern unsigned int  softlockup_panic;
387 extern unsigned int  hardlockup_panic;
388 void lockup_detector_init(void);
389 #else
390 static inline void touch_softlockup_watchdog(void)
391 {
392 }
393 static inline void touch_softlockup_watchdog_sync(void)
394 {
395 }
396 static inline void touch_all_softlockup_watchdogs(void)
397 {
398 }
399 static inline void lockup_detector_init(void)
400 {
401 }
402 #endif
403 
404 #ifdef CONFIG_DETECT_HUNG_TASK
405 void reset_hung_task_detector(void);
406 #else
407 static inline void reset_hung_task_detector(void)
408 {
409 }
410 #endif
411 
412 /* Attach to any functions which should be ignored in wchan output. */
413 #define __sched		__attribute__((__section__(".sched.text")))
414 
415 /* Linker adds these: start and end of __sched functions */
416 extern char __sched_text_start[], __sched_text_end[];
417 
418 /* Is this address in the __sched functions? */
419 extern int in_sched_functions(unsigned long addr);
420 
421 #define	MAX_SCHEDULE_TIMEOUT	LONG_MAX
422 extern signed long schedule_timeout(signed long timeout);
423 extern signed long schedule_timeout_interruptible(signed long timeout);
424 extern signed long schedule_timeout_killable(signed long timeout);
425 extern signed long schedule_timeout_uninterruptible(signed long timeout);
426 asmlinkage void schedule(void);
427 extern void schedule_preempt_disabled(void);
428 
429 extern long io_schedule_timeout(long timeout);
430 
431 static inline void io_schedule(void)
432 {
433 	io_schedule_timeout(MAX_SCHEDULE_TIMEOUT);
434 }
435 
436 struct nsproxy;
437 struct user_namespace;
438 
439 #ifdef CONFIG_MMU
440 extern void arch_pick_mmap_layout(struct mm_struct *mm);
441 extern unsigned long
442 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
443 		       unsigned long, unsigned long);
444 extern unsigned long
445 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
446 			  unsigned long len, unsigned long pgoff,
447 			  unsigned long flags);
448 #else
449 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
450 #endif
451 
452 #define SUID_DUMP_DISABLE	0	/* No setuid dumping */
453 #define SUID_DUMP_USER		1	/* Dump as user of process */
454 #define SUID_DUMP_ROOT		2	/* Dump as root */
455 
456 /* mm flags */
457 
458 /* for SUID_DUMP_* above */
459 #define MMF_DUMPABLE_BITS 2
460 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
461 
462 extern void set_dumpable(struct mm_struct *mm, int value);
463 /*
464  * This returns the actual value of the suid_dumpable flag. For things
465  * that are using this for checking for privilege transitions, it must
466  * test against SUID_DUMP_USER rather than treating it as a boolean
467  * value.
468  */
469 static inline int __get_dumpable(unsigned long mm_flags)
470 {
471 	return mm_flags & MMF_DUMPABLE_MASK;
472 }
473 
474 static inline int get_dumpable(struct mm_struct *mm)
475 {
476 	return __get_dumpable(mm->flags);
477 }
478 
479 /* coredump filter bits */
480 #define MMF_DUMP_ANON_PRIVATE	2
481 #define MMF_DUMP_ANON_SHARED	3
482 #define MMF_DUMP_MAPPED_PRIVATE	4
483 #define MMF_DUMP_MAPPED_SHARED	5
484 #define MMF_DUMP_ELF_HEADERS	6
485 #define MMF_DUMP_HUGETLB_PRIVATE 7
486 #define MMF_DUMP_HUGETLB_SHARED  8
487 
488 #define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
489 #define MMF_DUMP_FILTER_BITS	7
490 #define MMF_DUMP_FILTER_MASK \
491 	(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
492 #define MMF_DUMP_FILTER_DEFAULT \
493 	((1 << MMF_DUMP_ANON_PRIVATE) |	(1 << MMF_DUMP_ANON_SHARED) |\
494 	 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
495 
496 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
497 # define MMF_DUMP_MASK_DEFAULT_ELF	(1 << MMF_DUMP_ELF_HEADERS)
498 #else
499 # define MMF_DUMP_MASK_DEFAULT_ELF	0
500 #endif
501 					/* leave room for more dump flags */
502 #define MMF_VM_MERGEABLE	16	/* KSM may merge identical pages */
503 #define MMF_VM_HUGEPAGE		17	/* set when VM_HUGEPAGE is set on vma */
504 #define MMF_EXE_FILE_CHANGED	18	/* see prctl_set_mm_exe_file() */
505 
506 #define MMF_HAS_UPROBES		19	/* has uprobes */
507 #define MMF_RECALC_UPROBES	20	/* MMF_HAS_UPROBES can be wrong */
508 
509 #define MMF_INIT_MASK		(MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
510 
511 struct sighand_struct {
512 	atomic_t		count;
513 	struct k_sigaction	action[_NSIG];
514 	spinlock_t		siglock;
515 	wait_queue_head_t	signalfd_wqh;
516 };
517 
518 struct pacct_struct {
519 	int			ac_flag;
520 	long			ac_exitcode;
521 	unsigned long		ac_mem;
522 	cputime_t		ac_utime, ac_stime;
523 	unsigned long		ac_minflt, ac_majflt;
524 };
525 
526 struct cpu_itimer {
527 	cputime_t expires;
528 	cputime_t incr;
529 	u32 error;
530 	u32 incr_error;
531 };
532 
533 /**
534  * struct prev_cputime - snaphsot of system and user cputime
535  * @utime: time spent in user mode
536  * @stime: time spent in system mode
537  * @lock: protects the above two fields
538  *
539  * Stores previous user/system time values such that we can guarantee
540  * monotonicity.
541  */
542 struct prev_cputime {
543 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
544 	cputime_t utime;
545 	cputime_t stime;
546 	raw_spinlock_t lock;
547 #endif
548 };
549 
550 static inline void prev_cputime_init(struct prev_cputime *prev)
551 {
552 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
553 	prev->utime = prev->stime = 0;
554 	raw_spin_lock_init(&prev->lock);
555 #endif
556 }
557 
558 /**
559  * struct task_cputime - collected CPU time counts
560  * @utime:		time spent in user mode, in &cputime_t units
561  * @stime:		time spent in kernel mode, in &cputime_t units
562  * @sum_exec_runtime:	total time spent on the CPU, in nanoseconds
563  *
564  * This structure groups together three kinds of CPU time that are tracked for
565  * threads and thread groups.  Most things considering CPU time want to group
566  * these counts together and treat all three of them in parallel.
567  */
568 struct task_cputime {
569 	cputime_t utime;
570 	cputime_t stime;
571 	unsigned long long sum_exec_runtime;
572 };
573 
574 /* Alternate field names when used to cache expirations. */
575 #define virt_exp	utime
576 #define prof_exp	stime
577 #define sched_exp	sum_exec_runtime
578 
579 #define INIT_CPUTIME	\
580 	(struct task_cputime) {					\
581 		.utime = 0,					\
582 		.stime = 0,					\
583 		.sum_exec_runtime = 0,				\
584 	}
585 
586 /*
587  * This is the atomic variant of task_cputime, which can be used for
588  * storing and updating task_cputime statistics without locking.
589  */
590 struct task_cputime_atomic {
591 	atomic64_t utime;
592 	atomic64_t stime;
593 	atomic64_t sum_exec_runtime;
594 };
595 
596 #define INIT_CPUTIME_ATOMIC \
597 	(struct task_cputime_atomic) {				\
598 		.utime = ATOMIC64_INIT(0),			\
599 		.stime = ATOMIC64_INIT(0),			\
600 		.sum_exec_runtime = ATOMIC64_INIT(0),		\
601 	}
602 
603 #define PREEMPT_DISABLED	(PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
604 
605 /*
606  * Disable preemption until the scheduler is running -- use an unconditional
607  * value so that it also works on !PREEMPT_COUNT kernels.
608  *
609  * Reset by start_kernel()->sched_init()->init_idle()->init_idle_preempt_count().
610  */
611 #define INIT_PREEMPT_COUNT	PREEMPT_OFFSET
612 
613 /*
614  * Initial preempt_count value; reflects the preempt_count schedule invariant
615  * which states that during context switches:
616  *
617  *    preempt_count() == 2*PREEMPT_DISABLE_OFFSET
618  *
619  * Note: PREEMPT_DISABLE_OFFSET is 0 for !PREEMPT_COUNT kernels.
620  * Note: See finish_task_switch().
621  */
622 #define FORK_PREEMPT_COUNT	(2*PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
623 
624 /**
625  * struct thread_group_cputimer - thread group interval timer counts
626  * @cputime_atomic:	atomic thread group interval timers.
627  * @running:		true when there are timers running and
628  *			@cputime_atomic receives updates.
629  * @checking_timer:	true when a thread in the group is in the
630  *			process of checking for thread group timers.
631  *
632  * This structure contains the version of task_cputime, above, that is
633  * used for thread group CPU timer calculations.
634  */
635 struct thread_group_cputimer {
636 	struct task_cputime_atomic cputime_atomic;
637 	bool running;
638 	bool checking_timer;
639 };
640 
641 #include <linux/rwsem.h>
642 struct autogroup;
643 
644 /*
645  * NOTE! "signal_struct" does not have its own
646  * locking, because a shared signal_struct always
647  * implies a shared sighand_struct, so locking
648  * sighand_struct is always a proper superset of
649  * the locking of signal_struct.
650  */
651 struct signal_struct {
652 	atomic_t		sigcnt;
653 	atomic_t		live;
654 	int			nr_threads;
655 	struct list_head	thread_head;
656 
657 	wait_queue_head_t	wait_chldexit;	/* for wait4() */
658 
659 	/* current thread group signal load-balancing target: */
660 	struct task_struct	*curr_target;
661 
662 	/* shared signal handling: */
663 	struct sigpending	shared_pending;
664 
665 	/* thread group exit support */
666 	int			group_exit_code;
667 	/* overloaded:
668 	 * - notify group_exit_task when ->count is equal to notify_count
669 	 * - everyone except group_exit_task is stopped during signal delivery
670 	 *   of fatal signals, group_exit_task processes the signal.
671 	 */
672 	int			notify_count;
673 	struct task_struct	*group_exit_task;
674 
675 	/* thread group stop support, overloads group_exit_code too */
676 	int			group_stop_count;
677 	unsigned int		flags; /* see SIGNAL_* flags below */
678 
679 	/*
680 	 * PR_SET_CHILD_SUBREAPER marks a process, like a service
681 	 * manager, to re-parent orphan (double-forking) child processes
682 	 * to this process instead of 'init'. The service manager is
683 	 * able to receive SIGCHLD signals and is able to investigate
684 	 * the process until it calls wait(). All children of this
685 	 * process will inherit a flag if they should look for a
686 	 * child_subreaper process at exit.
687 	 */
688 	unsigned int		is_child_subreaper:1;
689 	unsigned int		has_child_subreaper:1;
690 
691 	/* POSIX.1b Interval Timers */
692 	int			posix_timer_id;
693 	struct list_head	posix_timers;
694 
695 	/* ITIMER_REAL timer for the process */
696 	struct hrtimer real_timer;
697 	struct pid *leader_pid;
698 	ktime_t it_real_incr;
699 
700 	/*
701 	 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
702 	 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
703 	 * values are defined to 0 and 1 respectively
704 	 */
705 	struct cpu_itimer it[2];
706 
707 	/*
708 	 * Thread group totals for process CPU timers.
709 	 * See thread_group_cputimer(), et al, for details.
710 	 */
711 	struct thread_group_cputimer cputimer;
712 
713 	/* Earliest-expiration cache. */
714 	struct task_cputime cputime_expires;
715 
716 	struct list_head cpu_timers[3];
717 
718 	struct pid *tty_old_pgrp;
719 
720 	/* boolean value for session group leader */
721 	int leader;
722 
723 	struct tty_struct *tty; /* NULL if no tty */
724 
725 #ifdef CONFIG_SCHED_AUTOGROUP
726 	struct autogroup *autogroup;
727 #endif
728 	/*
729 	 * Cumulative resource counters for dead threads in the group,
730 	 * and for reaped dead child processes forked by this group.
731 	 * Live threads maintain their own counters and add to these
732 	 * in __exit_signal, except for the group leader.
733 	 */
734 	seqlock_t stats_lock;
735 	cputime_t utime, stime, cutime, cstime;
736 	cputime_t gtime;
737 	cputime_t cgtime;
738 	struct prev_cputime prev_cputime;
739 	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
740 	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
741 	unsigned long inblock, oublock, cinblock, coublock;
742 	unsigned long maxrss, cmaxrss;
743 	struct task_io_accounting ioac;
744 
745 	/*
746 	 * Cumulative ns of schedule CPU time fo dead threads in the
747 	 * group, not including a zombie group leader, (This only differs
748 	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
749 	 * other than jiffies.)
750 	 */
751 	unsigned long long sum_sched_runtime;
752 
753 	/*
754 	 * We don't bother to synchronize most readers of this at all,
755 	 * because there is no reader checking a limit that actually needs
756 	 * to get both rlim_cur and rlim_max atomically, and either one
757 	 * alone is a single word that can safely be read normally.
758 	 * getrlimit/setrlimit use task_lock(current->group_leader) to
759 	 * protect this instead of the siglock, because they really
760 	 * have no need to disable irqs.
761 	 */
762 	struct rlimit rlim[RLIM_NLIMITS];
763 
764 #ifdef CONFIG_BSD_PROCESS_ACCT
765 	struct pacct_struct pacct;	/* per-process accounting information */
766 #endif
767 #ifdef CONFIG_TASKSTATS
768 	struct taskstats *stats;
769 #endif
770 #ifdef CONFIG_AUDIT
771 	unsigned audit_tty;
772 	unsigned audit_tty_log_passwd;
773 	struct tty_audit_buf *tty_audit_buf;
774 #endif
775 
776 	oom_flags_t oom_flags;
777 	short oom_score_adj;		/* OOM kill score adjustment */
778 	short oom_score_adj_min;	/* OOM kill score adjustment min value.
779 					 * Only settable by CAP_SYS_RESOURCE. */
780 
781 	struct mutex cred_guard_mutex;	/* guard against foreign influences on
782 					 * credential calculations
783 					 * (notably. ptrace) */
784 };
785 
786 /*
787  * Bits in flags field of signal_struct.
788  */
789 #define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
790 #define SIGNAL_STOP_CONTINUED	0x00000002 /* SIGCONT since WCONTINUED reap */
791 #define SIGNAL_GROUP_EXIT	0x00000004 /* group exit in progress */
792 #define SIGNAL_GROUP_COREDUMP	0x00000008 /* coredump in progress */
793 /*
794  * Pending notifications to parent.
795  */
796 #define SIGNAL_CLD_STOPPED	0x00000010
797 #define SIGNAL_CLD_CONTINUED	0x00000020
798 #define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
799 
800 #define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */
801 
802 /* If true, all threads except ->group_exit_task have pending SIGKILL */
803 static inline int signal_group_exit(const struct signal_struct *sig)
804 {
805 	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
806 		(sig->group_exit_task != NULL);
807 }
808 
809 /*
810  * Some day this will be a full-fledged user tracking system..
811  */
812 struct user_struct {
813 	atomic_t __count;	/* reference count */
814 	atomic_t processes;	/* How many processes does this user have? */
815 	atomic_t sigpending;	/* How many pending signals does this user have? */
816 #ifdef CONFIG_INOTIFY_USER
817 	atomic_t inotify_watches; /* How many inotify watches does this user have? */
818 	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
819 #endif
820 #ifdef CONFIG_FANOTIFY
821 	atomic_t fanotify_listeners;
822 #endif
823 #ifdef CONFIG_EPOLL
824 	atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
825 #endif
826 #ifdef CONFIG_POSIX_MQUEUE
827 	/* protected by mq_lock	*/
828 	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
829 #endif
830 	unsigned long locked_shm; /* How many pages of mlocked shm ? */
831 
832 #ifdef CONFIG_KEYS
833 	struct key *uid_keyring;	/* UID specific keyring */
834 	struct key *session_keyring;	/* UID's default session keyring */
835 #endif
836 
837 	/* Hash table maintenance information */
838 	struct hlist_node uidhash_node;
839 	kuid_t uid;
840 
841 #if defined(CONFIG_PERF_EVENTS) || defined(CONFIG_BPF_SYSCALL)
842 	atomic_long_t locked_vm;
843 #endif
844 };
845 
846 extern int uids_sysfs_init(void);
847 
848 extern struct user_struct *find_user(kuid_t);
849 
850 extern struct user_struct root_user;
851 #define INIT_USER (&root_user)
852 
853 
854 struct backing_dev_info;
855 struct reclaim_state;
856 
857 #ifdef CONFIG_SCHED_INFO
858 struct sched_info {
859 	/* cumulative counters */
860 	unsigned long pcount;	      /* # of times run on this cpu */
861 	unsigned long long run_delay; /* time spent waiting on a runqueue */
862 
863 	/* timestamps */
864 	unsigned long long last_arrival,/* when we last ran on a cpu */
865 			   last_queued;	/* when we were last queued to run */
866 };
867 #endif /* CONFIG_SCHED_INFO */
868 
869 #ifdef CONFIG_TASK_DELAY_ACCT
870 struct task_delay_info {
871 	spinlock_t	lock;
872 	unsigned int	flags;	/* Private per-task flags */
873 
874 	/* For each stat XXX, add following, aligned appropriately
875 	 *
876 	 * struct timespec XXX_start, XXX_end;
877 	 * u64 XXX_delay;
878 	 * u32 XXX_count;
879 	 *
880 	 * Atomicity of updates to XXX_delay, XXX_count protected by
881 	 * single lock above (split into XXX_lock if contention is an issue).
882 	 */
883 
884 	/*
885 	 * XXX_count is incremented on every XXX operation, the delay
886 	 * associated with the operation is added to XXX_delay.
887 	 * XXX_delay contains the accumulated delay time in nanoseconds.
888 	 */
889 	u64 blkio_start;	/* Shared by blkio, swapin */
890 	u64 blkio_delay;	/* wait for sync block io completion */
891 	u64 swapin_delay;	/* wait for swapin block io completion */
892 	u32 blkio_count;	/* total count of the number of sync block */
893 				/* io operations performed */
894 	u32 swapin_count;	/* total count of the number of swapin block */
895 				/* io operations performed */
896 
897 	u64 freepages_start;
898 	u64 freepages_delay;	/* wait for memory reclaim */
899 	u32 freepages_count;	/* total count of memory reclaim */
900 };
901 #endif	/* CONFIG_TASK_DELAY_ACCT */
902 
903 static inline int sched_info_on(void)
904 {
905 #ifdef CONFIG_SCHEDSTATS
906 	return 1;
907 #elif defined(CONFIG_TASK_DELAY_ACCT)
908 	extern int delayacct_on;
909 	return delayacct_on;
910 #else
911 	return 0;
912 #endif
913 }
914 
915 enum cpu_idle_type {
916 	CPU_IDLE,
917 	CPU_NOT_IDLE,
918 	CPU_NEWLY_IDLE,
919 	CPU_MAX_IDLE_TYPES
920 };
921 
922 /*
923  * Increase resolution of cpu_capacity calculations
924  */
925 #define SCHED_CAPACITY_SHIFT	10
926 #define SCHED_CAPACITY_SCALE	(1L << SCHED_CAPACITY_SHIFT)
927 
928 /*
929  * Wake-queues are lists of tasks with a pending wakeup, whose
930  * callers have already marked the task as woken internally,
931  * and can thus carry on. A common use case is being able to
932  * do the wakeups once the corresponding user lock as been
933  * released.
934  *
935  * We hold reference to each task in the list across the wakeup,
936  * thus guaranteeing that the memory is still valid by the time
937  * the actual wakeups are performed in wake_up_q().
938  *
939  * One per task suffices, because there's never a need for a task to be
940  * in two wake queues simultaneously; it is forbidden to abandon a task
941  * in a wake queue (a call to wake_up_q() _must_ follow), so if a task is
942  * already in a wake queue, the wakeup will happen soon and the second
943  * waker can just skip it.
944  *
945  * The WAKE_Q macro declares and initializes the list head.
946  * wake_up_q() does NOT reinitialize the list; it's expected to be
947  * called near the end of a function, where the fact that the queue is
948  * not used again will be easy to see by inspection.
949  *
950  * Note that this can cause spurious wakeups. schedule() callers
951  * must ensure the call is done inside a loop, confirming that the
952  * wakeup condition has in fact occurred.
953  */
954 struct wake_q_node {
955 	struct wake_q_node *next;
956 };
957 
958 struct wake_q_head {
959 	struct wake_q_node *first;
960 	struct wake_q_node **lastp;
961 };
962 
963 #define WAKE_Q_TAIL ((struct wake_q_node *) 0x01)
964 
965 #define WAKE_Q(name)					\
966 	struct wake_q_head name = { WAKE_Q_TAIL, &name.first }
967 
968 extern void wake_q_add(struct wake_q_head *head,
969 		       struct task_struct *task);
970 extern void wake_up_q(struct wake_q_head *head);
971 
972 /*
973  * sched-domains (multiprocessor balancing) declarations:
974  */
975 #ifdef CONFIG_SMP
976 #define SD_LOAD_BALANCE		0x0001	/* Do load balancing on this domain. */
977 #define SD_BALANCE_NEWIDLE	0x0002	/* Balance when about to become idle */
978 #define SD_BALANCE_EXEC		0x0004	/* Balance on exec */
979 #define SD_BALANCE_FORK		0x0008	/* Balance on fork, clone */
980 #define SD_BALANCE_WAKE		0x0010  /* Balance on wakeup */
981 #define SD_WAKE_AFFINE		0x0020	/* Wake task to waking CPU */
982 #define SD_SHARE_CPUCAPACITY	0x0080	/* Domain members share cpu power */
983 #define SD_SHARE_POWERDOMAIN	0x0100	/* Domain members share power domain */
984 #define SD_SHARE_PKG_RESOURCES	0x0200	/* Domain members share cpu pkg resources */
985 #define SD_SERIALIZE		0x0400	/* Only a single load balancing instance */
986 #define SD_ASYM_PACKING		0x0800  /* Place busy groups earlier in the domain */
987 #define SD_PREFER_SIBLING	0x1000	/* Prefer to place tasks in a sibling domain */
988 #define SD_OVERLAP		0x2000	/* sched_domains of this level overlap */
989 #define SD_NUMA			0x4000	/* cross-node balancing */
990 
991 #ifdef CONFIG_SCHED_SMT
992 static inline int cpu_smt_flags(void)
993 {
994 	return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES;
995 }
996 #endif
997 
998 #ifdef CONFIG_SCHED_MC
999 static inline int cpu_core_flags(void)
1000 {
1001 	return SD_SHARE_PKG_RESOURCES;
1002 }
1003 #endif
1004 
1005 #ifdef CONFIG_NUMA
1006 static inline int cpu_numa_flags(void)
1007 {
1008 	return SD_NUMA;
1009 }
1010 #endif
1011 
1012 struct sched_domain_attr {
1013 	int relax_domain_level;
1014 };
1015 
1016 #define SD_ATTR_INIT	(struct sched_domain_attr) {	\
1017 	.relax_domain_level = -1,			\
1018 }
1019 
1020 extern int sched_domain_level_max;
1021 
1022 struct sched_group;
1023 
1024 struct sched_domain {
1025 	/* These fields must be setup */
1026 	struct sched_domain *parent;	/* top domain must be null terminated */
1027 	struct sched_domain *child;	/* bottom domain must be null terminated */
1028 	struct sched_group *groups;	/* the balancing groups of the domain */
1029 	unsigned long min_interval;	/* Minimum balance interval ms */
1030 	unsigned long max_interval;	/* Maximum balance interval ms */
1031 	unsigned int busy_factor;	/* less balancing by factor if busy */
1032 	unsigned int imbalance_pct;	/* No balance until over watermark */
1033 	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
1034 	unsigned int busy_idx;
1035 	unsigned int idle_idx;
1036 	unsigned int newidle_idx;
1037 	unsigned int wake_idx;
1038 	unsigned int forkexec_idx;
1039 	unsigned int smt_gain;
1040 
1041 	int nohz_idle;			/* NOHZ IDLE status */
1042 	int flags;			/* See SD_* */
1043 	int level;
1044 
1045 	/* Runtime fields. */
1046 	unsigned long last_balance;	/* init to jiffies. units in jiffies */
1047 	unsigned int balance_interval;	/* initialise to 1. units in ms. */
1048 	unsigned int nr_balance_failed; /* initialise to 0 */
1049 
1050 	/* idle_balance() stats */
1051 	u64 max_newidle_lb_cost;
1052 	unsigned long next_decay_max_lb_cost;
1053 
1054 #ifdef CONFIG_SCHEDSTATS
1055 	/* load_balance() stats */
1056 	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
1057 	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
1058 	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
1059 	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
1060 	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
1061 	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
1062 	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
1063 	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
1064 
1065 	/* Active load balancing */
1066 	unsigned int alb_count;
1067 	unsigned int alb_failed;
1068 	unsigned int alb_pushed;
1069 
1070 	/* SD_BALANCE_EXEC stats */
1071 	unsigned int sbe_count;
1072 	unsigned int sbe_balanced;
1073 	unsigned int sbe_pushed;
1074 
1075 	/* SD_BALANCE_FORK stats */
1076 	unsigned int sbf_count;
1077 	unsigned int sbf_balanced;
1078 	unsigned int sbf_pushed;
1079 
1080 	/* try_to_wake_up() stats */
1081 	unsigned int ttwu_wake_remote;
1082 	unsigned int ttwu_move_affine;
1083 	unsigned int ttwu_move_balance;
1084 #endif
1085 #ifdef CONFIG_SCHED_DEBUG
1086 	char *name;
1087 #endif
1088 	union {
1089 		void *private;		/* used during construction */
1090 		struct rcu_head rcu;	/* used during destruction */
1091 	};
1092 
1093 	unsigned int span_weight;
1094 	/*
1095 	 * Span of all CPUs in this domain.
1096 	 *
1097 	 * NOTE: this field is variable length. (Allocated dynamically
1098 	 * by attaching extra space to the end of the structure,
1099 	 * depending on how many CPUs the kernel has booted up with)
1100 	 */
1101 	unsigned long span[0];
1102 };
1103 
1104 static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
1105 {
1106 	return to_cpumask(sd->span);
1107 }
1108 
1109 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1110 				    struct sched_domain_attr *dattr_new);
1111 
1112 /* Allocate an array of sched domains, for partition_sched_domains(). */
1113 cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
1114 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
1115 
1116 bool cpus_share_cache(int this_cpu, int that_cpu);
1117 
1118 typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
1119 typedef int (*sched_domain_flags_f)(void);
1120 
1121 #define SDTL_OVERLAP	0x01
1122 
1123 struct sd_data {
1124 	struct sched_domain **__percpu sd;
1125 	struct sched_group **__percpu sg;
1126 	struct sched_group_capacity **__percpu sgc;
1127 };
1128 
1129 struct sched_domain_topology_level {
1130 	sched_domain_mask_f mask;
1131 	sched_domain_flags_f sd_flags;
1132 	int		    flags;
1133 	int		    numa_level;
1134 	struct sd_data      data;
1135 #ifdef CONFIG_SCHED_DEBUG
1136 	char                *name;
1137 #endif
1138 };
1139 
1140 extern void set_sched_topology(struct sched_domain_topology_level *tl);
1141 extern void wake_up_if_idle(int cpu);
1142 
1143 #ifdef CONFIG_SCHED_DEBUG
1144 # define SD_INIT_NAME(type)		.name = #type
1145 #else
1146 # define SD_INIT_NAME(type)
1147 #endif
1148 
1149 #else /* CONFIG_SMP */
1150 
1151 struct sched_domain_attr;
1152 
1153 static inline void
1154 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1155 			struct sched_domain_attr *dattr_new)
1156 {
1157 }
1158 
1159 static inline bool cpus_share_cache(int this_cpu, int that_cpu)
1160 {
1161 	return true;
1162 }
1163 
1164 #endif	/* !CONFIG_SMP */
1165 
1166 
1167 struct io_context;			/* See blkdev.h */
1168 
1169 
1170 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1171 extern void prefetch_stack(struct task_struct *t);
1172 #else
1173 static inline void prefetch_stack(struct task_struct *t) { }
1174 #endif
1175 
1176 struct audit_context;		/* See audit.c */
1177 struct mempolicy;
1178 struct pipe_inode_info;
1179 struct uts_namespace;
1180 
1181 struct load_weight {
1182 	unsigned long weight;
1183 	u32 inv_weight;
1184 };
1185 
1186 /*
1187  * The load_avg/util_avg accumulates an infinite geometric series.
1188  * 1) load_avg factors frequency scaling into the amount of time that a
1189  * sched_entity is runnable on a rq into its weight. For cfs_rq, it is the
1190  * aggregated such weights of all runnable and blocked sched_entities.
1191  * 2) util_avg factors frequency and cpu scaling into the amount of time
1192  * that a sched_entity is running on a CPU, in the range [0..SCHED_LOAD_SCALE].
1193  * For cfs_rq, it is the aggregated such times of all runnable and
1194  * blocked sched_entities.
1195  * The 64 bit load_sum can:
1196  * 1) for cfs_rq, afford 4353082796 (=2^64/47742/88761) entities with
1197  * the highest weight (=88761) always runnable, we should not overflow
1198  * 2) for entity, support any load.weight always runnable
1199  */
1200 struct sched_avg {
1201 	u64 last_update_time, load_sum;
1202 	u32 util_sum, period_contrib;
1203 	unsigned long load_avg, util_avg;
1204 };
1205 
1206 #ifdef CONFIG_SCHEDSTATS
1207 struct sched_statistics {
1208 	u64			wait_start;
1209 	u64			wait_max;
1210 	u64			wait_count;
1211 	u64			wait_sum;
1212 	u64			iowait_count;
1213 	u64			iowait_sum;
1214 
1215 	u64			sleep_start;
1216 	u64			sleep_max;
1217 	s64			sum_sleep_runtime;
1218 
1219 	u64			block_start;
1220 	u64			block_max;
1221 	u64			exec_max;
1222 	u64			slice_max;
1223 
1224 	u64			nr_migrations_cold;
1225 	u64			nr_failed_migrations_affine;
1226 	u64			nr_failed_migrations_running;
1227 	u64			nr_failed_migrations_hot;
1228 	u64			nr_forced_migrations;
1229 
1230 	u64			nr_wakeups;
1231 	u64			nr_wakeups_sync;
1232 	u64			nr_wakeups_migrate;
1233 	u64			nr_wakeups_local;
1234 	u64			nr_wakeups_remote;
1235 	u64			nr_wakeups_affine;
1236 	u64			nr_wakeups_affine_attempts;
1237 	u64			nr_wakeups_passive;
1238 	u64			nr_wakeups_idle;
1239 };
1240 #endif
1241 
1242 struct sched_entity {
1243 	struct load_weight	load;		/* for load-balancing */
1244 	struct rb_node		run_node;
1245 	struct list_head	group_node;
1246 	unsigned int		on_rq;
1247 
1248 	u64			exec_start;
1249 	u64			sum_exec_runtime;
1250 	u64			vruntime;
1251 	u64			prev_sum_exec_runtime;
1252 
1253 	u64			nr_migrations;
1254 
1255 #ifdef CONFIG_SCHEDSTATS
1256 	struct sched_statistics statistics;
1257 #endif
1258 
1259 #ifdef CONFIG_FAIR_GROUP_SCHED
1260 	int			depth;
1261 	struct sched_entity	*parent;
1262 	/* rq on which this entity is (to be) queued: */
1263 	struct cfs_rq		*cfs_rq;
1264 	/* rq "owned" by this entity/group: */
1265 	struct cfs_rq		*my_q;
1266 #endif
1267 
1268 #ifdef CONFIG_SMP
1269 	/* Per entity load average tracking */
1270 	struct sched_avg	avg;
1271 #endif
1272 };
1273 
1274 struct sched_rt_entity {
1275 	struct list_head run_list;
1276 	unsigned long timeout;
1277 	unsigned long watchdog_stamp;
1278 	unsigned int time_slice;
1279 
1280 	struct sched_rt_entity *back;
1281 #ifdef CONFIG_RT_GROUP_SCHED
1282 	struct sched_rt_entity	*parent;
1283 	/* rq on which this entity is (to be) queued: */
1284 	struct rt_rq		*rt_rq;
1285 	/* rq "owned" by this entity/group: */
1286 	struct rt_rq		*my_q;
1287 #endif
1288 };
1289 
1290 struct sched_dl_entity {
1291 	struct rb_node	rb_node;
1292 
1293 	/*
1294 	 * Original scheduling parameters. Copied here from sched_attr
1295 	 * during sched_setattr(), they will remain the same until
1296 	 * the next sched_setattr().
1297 	 */
1298 	u64 dl_runtime;		/* maximum runtime for each instance	*/
1299 	u64 dl_deadline;	/* relative deadline of each instance	*/
1300 	u64 dl_period;		/* separation of two instances (period) */
1301 	u64 dl_bw;		/* dl_runtime / dl_deadline		*/
1302 
1303 	/*
1304 	 * Actual scheduling parameters. Initialized with the values above,
1305 	 * they are continously updated during task execution. Note that
1306 	 * the remaining runtime could be < 0 in case we are in overrun.
1307 	 */
1308 	s64 runtime;		/* remaining runtime for this instance	*/
1309 	u64 deadline;		/* absolute deadline for this instance	*/
1310 	unsigned int flags;	/* specifying the scheduler behaviour	*/
1311 
1312 	/*
1313 	 * Some bool flags:
1314 	 *
1315 	 * @dl_throttled tells if we exhausted the runtime. If so, the
1316 	 * task has to wait for a replenishment to be performed at the
1317 	 * next firing of dl_timer.
1318 	 *
1319 	 * @dl_new tells if a new instance arrived. If so we must
1320 	 * start executing it with full runtime and reset its absolute
1321 	 * deadline;
1322 	 *
1323 	 * @dl_boosted tells if we are boosted due to DI. If so we are
1324 	 * outside bandwidth enforcement mechanism (but only until we
1325 	 * exit the critical section);
1326 	 *
1327 	 * @dl_yielded tells if task gave up the cpu before consuming
1328 	 * all its available runtime during the last job.
1329 	 */
1330 	int dl_throttled, dl_new, dl_boosted, dl_yielded;
1331 
1332 	/*
1333 	 * Bandwidth enforcement timer. Each -deadline task has its
1334 	 * own bandwidth to be enforced, thus we need one timer per task.
1335 	 */
1336 	struct hrtimer dl_timer;
1337 };
1338 
1339 union rcu_special {
1340 	struct {
1341 		u8 blocked;
1342 		u8 need_qs;
1343 		u8 exp_need_qs;
1344 		u8 pad;	/* Otherwise the compiler can store garbage here. */
1345 	} b; /* Bits. */
1346 	u32 s; /* Set of bits. */
1347 };
1348 struct rcu_node;
1349 
1350 enum perf_event_task_context {
1351 	perf_invalid_context = -1,
1352 	perf_hw_context = 0,
1353 	perf_sw_context,
1354 	perf_nr_task_contexts,
1355 };
1356 
1357 /* Track pages that require TLB flushes */
1358 struct tlbflush_unmap_batch {
1359 	/*
1360 	 * Each bit set is a CPU that potentially has a TLB entry for one of
1361 	 * the PFNs being flushed. See set_tlb_ubc_flush_pending().
1362 	 */
1363 	struct cpumask cpumask;
1364 
1365 	/* True if any bit in cpumask is set */
1366 	bool flush_required;
1367 
1368 	/*
1369 	 * If true then the PTE was dirty when unmapped. The entry must be
1370 	 * flushed before IO is initiated or a stale TLB entry potentially
1371 	 * allows an update without redirtying the page.
1372 	 */
1373 	bool writable;
1374 };
1375 
1376 struct task_struct {
1377 	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
1378 	void *stack;
1379 	atomic_t usage;
1380 	unsigned int flags;	/* per process flags, defined below */
1381 	unsigned int ptrace;
1382 
1383 #ifdef CONFIG_SMP
1384 	struct llist_node wake_entry;
1385 	int on_cpu;
1386 	unsigned int wakee_flips;
1387 	unsigned long wakee_flip_decay_ts;
1388 	struct task_struct *last_wakee;
1389 
1390 	int wake_cpu;
1391 #endif
1392 	int on_rq;
1393 
1394 	int prio, static_prio, normal_prio;
1395 	unsigned int rt_priority;
1396 	const struct sched_class *sched_class;
1397 	struct sched_entity se;
1398 	struct sched_rt_entity rt;
1399 #ifdef CONFIG_CGROUP_SCHED
1400 	struct task_group *sched_task_group;
1401 #endif
1402 	struct sched_dl_entity dl;
1403 
1404 #ifdef CONFIG_PREEMPT_NOTIFIERS
1405 	/* list of struct preempt_notifier: */
1406 	struct hlist_head preempt_notifiers;
1407 #endif
1408 
1409 #ifdef CONFIG_BLK_DEV_IO_TRACE
1410 	unsigned int btrace_seq;
1411 #endif
1412 
1413 	unsigned int policy;
1414 	int nr_cpus_allowed;
1415 	cpumask_t cpus_allowed;
1416 
1417 #ifdef CONFIG_PREEMPT_RCU
1418 	int rcu_read_lock_nesting;
1419 	union rcu_special rcu_read_unlock_special;
1420 	struct list_head rcu_node_entry;
1421 	struct rcu_node *rcu_blocked_node;
1422 #endif /* #ifdef CONFIG_PREEMPT_RCU */
1423 #ifdef CONFIG_TASKS_RCU
1424 	unsigned long rcu_tasks_nvcsw;
1425 	bool rcu_tasks_holdout;
1426 	struct list_head rcu_tasks_holdout_list;
1427 	int rcu_tasks_idle_cpu;
1428 #endif /* #ifdef CONFIG_TASKS_RCU */
1429 
1430 #ifdef CONFIG_SCHED_INFO
1431 	struct sched_info sched_info;
1432 #endif
1433 
1434 	struct list_head tasks;
1435 #ifdef CONFIG_SMP
1436 	struct plist_node pushable_tasks;
1437 	struct rb_node pushable_dl_tasks;
1438 #endif
1439 
1440 	struct mm_struct *mm, *active_mm;
1441 	/* per-thread vma caching */
1442 	u32 vmacache_seqnum;
1443 	struct vm_area_struct *vmacache[VMACACHE_SIZE];
1444 #if defined(SPLIT_RSS_COUNTING)
1445 	struct task_rss_stat	rss_stat;
1446 #endif
1447 /* task state */
1448 	int exit_state;
1449 	int exit_code, exit_signal;
1450 	int pdeath_signal;  /*  The signal sent when the parent dies  */
1451 	unsigned long jobctl;	/* JOBCTL_*, siglock protected */
1452 
1453 	/* Used for emulating ABI behavior of previous Linux versions */
1454 	unsigned int personality;
1455 
1456 	unsigned in_execve:1;	/* Tell the LSMs that the process is doing an
1457 				 * execve */
1458 	unsigned in_iowait:1;
1459 
1460 	/* Revert to default priority/policy when forking */
1461 	unsigned sched_reset_on_fork:1;
1462 	unsigned sched_contributes_to_load:1;
1463 	unsigned sched_migrated:1;
1464 #ifdef CONFIG_MEMCG
1465 	unsigned memcg_may_oom:1;
1466 #endif
1467 #ifdef CONFIG_MEMCG_KMEM
1468 	unsigned memcg_kmem_skip_account:1;
1469 #endif
1470 #ifdef CONFIG_COMPAT_BRK
1471 	unsigned brk_randomized:1;
1472 #endif
1473 
1474 	unsigned long atomic_flags; /* Flags needing atomic access. */
1475 
1476 	struct restart_block restart_block;
1477 
1478 	pid_t pid;
1479 	pid_t tgid;
1480 
1481 #ifdef CONFIG_CC_STACKPROTECTOR
1482 	/* Canary value for the -fstack-protector gcc feature */
1483 	unsigned long stack_canary;
1484 #endif
1485 	/*
1486 	 * pointers to (original) parent process, youngest child, younger sibling,
1487 	 * older sibling, respectively.  (p->father can be replaced with
1488 	 * p->real_parent->pid)
1489 	 */
1490 	struct task_struct __rcu *real_parent; /* real parent process */
1491 	struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */
1492 	/*
1493 	 * children/sibling forms the list of my natural children
1494 	 */
1495 	struct list_head children;	/* list of my children */
1496 	struct list_head sibling;	/* linkage in my parent's children list */
1497 	struct task_struct *group_leader;	/* threadgroup leader */
1498 
1499 	/*
1500 	 * ptraced is the list of tasks this task is using ptrace on.
1501 	 * This includes both natural children and PTRACE_ATTACH targets.
1502 	 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1503 	 */
1504 	struct list_head ptraced;
1505 	struct list_head ptrace_entry;
1506 
1507 	/* PID/PID hash table linkage. */
1508 	struct pid_link pids[PIDTYPE_MAX];
1509 	struct list_head thread_group;
1510 	struct list_head thread_node;
1511 
1512 	struct completion *vfork_done;		/* for vfork() */
1513 	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
1514 	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
1515 
1516 	cputime_t utime, stime, utimescaled, stimescaled;
1517 	cputime_t gtime;
1518 	struct prev_cputime prev_cputime;
1519 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1520 	seqlock_t vtime_seqlock;
1521 	unsigned long long vtime_snap;
1522 	enum {
1523 		VTIME_SLEEPING = 0,
1524 		VTIME_USER,
1525 		VTIME_SYS,
1526 	} vtime_snap_whence;
1527 #endif
1528 	unsigned long nvcsw, nivcsw; /* context switch counts */
1529 	u64 start_time;		/* monotonic time in nsec */
1530 	u64 real_start_time;	/* boot based time in nsec */
1531 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1532 	unsigned long min_flt, maj_flt;
1533 
1534 	struct task_cputime cputime_expires;
1535 	struct list_head cpu_timers[3];
1536 
1537 /* process credentials */
1538 	const struct cred __rcu *real_cred; /* objective and real subjective task
1539 					 * credentials (COW) */
1540 	const struct cred __rcu *cred;	/* effective (overridable) subjective task
1541 					 * credentials (COW) */
1542 	char comm[TASK_COMM_LEN]; /* executable name excluding path
1543 				     - access with [gs]et_task_comm (which lock
1544 				       it with task_lock())
1545 				     - initialized normally by setup_new_exec */
1546 /* file system info */
1547 	struct nameidata *nameidata;
1548 #ifdef CONFIG_SYSVIPC
1549 /* ipc stuff */
1550 	struct sysv_sem sysvsem;
1551 	struct sysv_shm sysvshm;
1552 #endif
1553 #ifdef CONFIG_DETECT_HUNG_TASK
1554 /* hung task detection */
1555 	unsigned long last_switch_count;
1556 #endif
1557 /* filesystem information */
1558 	struct fs_struct *fs;
1559 /* open file information */
1560 	struct files_struct *files;
1561 /* namespaces */
1562 	struct nsproxy *nsproxy;
1563 /* signal handlers */
1564 	struct signal_struct *signal;
1565 	struct sighand_struct *sighand;
1566 
1567 	sigset_t blocked, real_blocked;
1568 	sigset_t saved_sigmask;	/* restored if set_restore_sigmask() was used */
1569 	struct sigpending pending;
1570 
1571 	unsigned long sas_ss_sp;
1572 	size_t sas_ss_size;
1573 
1574 	struct callback_head *task_works;
1575 
1576 	struct audit_context *audit_context;
1577 #ifdef CONFIG_AUDITSYSCALL
1578 	kuid_t loginuid;
1579 	unsigned int sessionid;
1580 #endif
1581 	struct seccomp seccomp;
1582 
1583 /* Thread group tracking */
1584    	u32 parent_exec_id;
1585    	u32 self_exec_id;
1586 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1587  * mempolicy */
1588 	spinlock_t alloc_lock;
1589 
1590 	/* Protection of the PI data structures: */
1591 	raw_spinlock_t pi_lock;
1592 
1593 	struct wake_q_node wake_q;
1594 
1595 #ifdef CONFIG_RT_MUTEXES
1596 	/* PI waiters blocked on a rt_mutex held by this task */
1597 	struct rb_root pi_waiters;
1598 	struct rb_node *pi_waiters_leftmost;
1599 	/* Deadlock detection and priority inheritance handling */
1600 	struct rt_mutex_waiter *pi_blocked_on;
1601 #endif
1602 
1603 #ifdef CONFIG_DEBUG_MUTEXES
1604 	/* mutex deadlock detection */
1605 	struct mutex_waiter *blocked_on;
1606 #endif
1607 #ifdef CONFIG_TRACE_IRQFLAGS
1608 	unsigned int irq_events;
1609 	unsigned long hardirq_enable_ip;
1610 	unsigned long hardirq_disable_ip;
1611 	unsigned int hardirq_enable_event;
1612 	unsigned int hardirq_disable_event;
1613 	int hardirqs_enabled;
1614 	int hardirq_context;
1615 	unsigned long softirq_disable_ip;
1616 	unsigned long softirq_enable_ip;
1617 	unsigned int softirq_disable_event;
1618 	unsigned int softirq_enable_event;
1619 	int softirqs_enabled;
1620 	int softirq_context;
1621 #endif
1622 #ifdef CONFIG_LOCKDEP
1623 # define MAX_LOCK_DEPTH 48UL
1624 	u64 curr_chain_key;
1625 	int lockdep_depth;
1626 	unsigned int lockdep_recursion;
1627 	struct held_lock held_locks[MAX_LOCK_DEPTH];
1628 	gfp_t lockdep_reclaim_gfp;
1629 #endif
1630 
1631 /* journalling filesystem info */
1632 	void *journal_info;
1633 
1634 /* stacked block device info */
1635 	struct bio_list *bio_list;
1636 
1637 #ifdef CONFIG_BLOCK
1638 /* stack plugging */
1639 	struct blk_plug *plug;
1640 #endif
1641 
1642 /* VM state */
1643 	struct reclaim_state *reclaim_state;
1644 
1645 	struct backing_dev_info *backing_dev_info;
1646 
1647 	struct io_context *io_context;
1648 
1649 	unsigned long ptrace_message;
1650 	siginfo_t *last_siginfo; /* For ptrace use.  */
1651 	struct task_io_accounting ioac;
1652 #if defined(CONFIG_TASK_XACCT)
1653 	u64 acct_rss_mem1;	/* accumulated rss usage */
1654 	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1655 	cputime_t acct_timexpd;	/* stime + utime since last update */
1656 #endif
1657 #ifdef CONFIG_CPUSETS
1658 	nodemask_t mems_allowed;	/* Protected by alloc_lock */
1659 	seqcount_t mems_allowed_seq;	/* Seqence no to catch updates */
1660 	int cpuset_mem_spread_rotor;
1661 	int cpuset_slab_spread_rotor;
1662 #endif
1663 #ifdef CONFIG_CGROUPS
1664 	/* Control Group info protected by css_set_lock */
1665 	struct css_set __rcu *cgroups;
1666 	/* cg_list protected by css_set_lock and tsk->alloc_lock */
1667 	struct list_head cg_list;
1668 #endif
1669 #ifdef CONFIG_FUTEX
1670 	struct robust_list_head __user *robust_list;
1671 #ifdef CONFIG_COMPAT
1672 	struct compat_robust_list_head __user *compat_robust_list;
1673 #endif
1674 	struct list_head pi_state_list;
1675 	struct futex_pi_state *pi_state_cache;
1676 #endif
1677 #ifdef CONFIG_PERF_EVENTS
1678 	struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1679 	struct mutex perf_event_mutex;
1680 	struct list_head perf_event_list;
1681 #endif
1682 #ifdef CONFIG_DEBUG_PREEMPT
1683 	unsigned long preempt_disable_ip;
1684 #endif
1685 #ifdef CONFIG_NUMA
1686 	struct mempolicy *mempolicy;	/* Protected by alloc_lock */
1687 	short il_next;
1688 	short pref_node_fork;
1689 #endif
1690 #ifdef CONFIG_NUMA_BALANCING
1691 	int numa_scan_seq;
1692 	unsigned int numa_scan_period;
1693 	unsigned int numa_scan_period_max;
1694 	int numa_preferred_nid;
1695 	unsigned long numa_migrate_retry;
1696 	u64 node_stamp;			/* migration stamp  */
1697 	u64 last_task_numa_placement;
1698 	u64 last_sum_exec_runtime;
1699 	struct callback_head numa_work;
1700 
1701 	struct list_head numa_entry;
1702 	struct numa_group *numa_group;
1703 
1704 	/*
1705 	 * numa_faults is an array split into four regions:
1706 	 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1707 	 * in this precise order.
1708 	 *
1709 	 * faults_memory: Exponential decaying average of faults on a per-node
1710 	 * basis. Scheduling placement decisions are made based on these
1711 	 * counts. The values remain static for the duration of a PTE scan.
1712 	 * faults_cpu: Track the nodes the process was running on when a NUMA
1713 	 * hinting fault was incurred.
1714 	 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1715 	 * during the current scan window. When the scan completes, the counts
1716 	 * in faults_memory and faults_cpu decay and these values are copied.
1717 	 */
1718 	unsigned long *numa_faults;
1719 	unsigned long total_numa_faults;
1720 
1721 	/*
1722 	 * numa_faults_locality tracks if faults recorded during the last
1723 	 * scan window were remote/local or failed to migrate. The task scan
1724 	 * period is adapted based on the locality of the faults with different
1725 	 * weights depending on whether they were shared or private faults
1726 	 */
1727 	unsigned long numa_faults_locality[3];
1728 
1729 	unsigned long numa_pages_migrated;
1730 #endif /* CONFIG_NUMA_BALANCING */
1731 
1732 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
1733 	struct tlbflush_unmap_batch tlb_ubc;
1734 #endif
1735 
1736 	struct rcu_head rcu;
1737 
1738 	/*
1739 	 * cache last used pipe for splice
1740 	 */
1741 	struct pipe_inode_info *splice_pipe;
1742 
1743 	struct page_frag task_frag;
1744 
1745 #ifdef	CONFIG_TASK_DELAY_ACCT
1746 	struct task_delay_info *delays;
1747 #endif
1748 #ifdef CONFIG_FAULT_INJECTION
1749 	int make_it_fail;
1750 #endif
1751 	/*
1752 	 * when (nr_dirtied >= nr_dirtied_pause), it's time to call
1753 	 * balance_dirty_pages() for some dirty throttling pause
1754 	 */
1755 	int nr_dirtied;
1756 	int nr_dirtied_pause;
1757 	unsigned long dirty_paused_when; /* start of a write-and-pause period */
1758 
1759 #ifdef CONFIG_LATENCYTOP
1760 	int latency_record_count;
1761 	struct latency_record latency_record[LT_SAVECOUNT];
1762 #endif
1763 	/*
1764 	 * time slack values; these are used to round up poll() and
1765 	 * select() etc timeout values. These are in nanoseconds.
1766 	 */
1767 	unsigned long timer_slack_ns;
1768 	unsigned long default_timer_slack_ns;
1769 
1770 #ifdef CONFIG_KASAN
1771 	unsigned int kasan_depth;
1772 #endif
1773 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1774 	/* Index of current stored address in ret_stack */
1775 	int curr_ret_stack;
1776 	/* Stack of return addresses for return function tracing */
1777 	struct ftrace_ret_stack	*ret_stack;
1778 	/* time stamp for last schedule */
1779 	unsigned long long ftrace_timestamp;
1780 	/*
1781 	 * Number of functions that haven't been traced
1782 	 * because of depth overrun.
1783 	 */
1784 	atomic_t trace_overrun;
1785 	/* Pause for the tracing */
1786 	atomic_t tracing_graph_pause;
1787 #endif
1788 #ifdef CONFIG_TRACING
1789 	/* state flags for use by tracers */
1790 	unsigned long trace;
1791 	/* bitmask and counter of trace recursion */
1792 	unsigned long trace_recursion;
1793 #endif /* CONFIG_TRACING */
1794 #ifdef CONFIG_MEMCG
1795 	struct mem_cgroup *memcg_in_oom;
1796 	gfp_t memcg_oom_gfp_mask;
1797 	int memcg_oom_order;
1798 
1799 	/* number of pages to reclaim on returning to userland */
1800 	unsigned int memcg_nr_pages_over_high;
1801 #endif
1802 #ifdef CONFIG_UPROBES
1803 	struct uprobe_task *utask;
1804 #endif
1805 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1806 	unsigned int	sequential_io;
1807 	unsigned int	sequential_io_avg;
1808 #endif
1809 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1810 	unsigned long	task_state_change;
1811 #endif
1812 	int pagefault_disabled;
1813 /* CPU-specific state of this task */
1814 	struct thread_struct thread;
1815 /*
1816  * WARNING: on x86, 'thread_struct' contains a variable-sized
1817  * structure.  It *MUST* be at the end of 'task_struct'.
1818  *
1819  * Do not put anything below here!
1820  */
1821 };
1822 
1823 #ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT
1824 extern int arch_task_struct_size __read_mostly;
1825 #else
1826 # define arch_task_struct_size (sizeof(struct task_struct))
1827 #endif
1828 
1829 /* Future-safe accessor for struct task_struct's cpus_allowed. */
1830 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1831 
1832 #define TNF_MIGRATED	0x01
1833 #define TNF_NO_GROUP	0x02
1834 #define TNF_SHARED	0x04
1835 #define TNF_FAULT_LOCAL	0x08
1836 #define TNF_MIGRATE_FAIL 0x10
1837 
1838 #ifdef CONFIG_NUMA_BALANCING
1839 extern void task_numa_fault(int last_node, int node, int pages, int flags);
1840 extern pid_t task_numa_group_id(struct task_struct *p);
1841 extern void set_numabalancing_state(bool enabled);
1842 extern void task_numa_free(struct task_struct *p);
1843 extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page,
1844 					int src_nid, int dst_cpu);
1845 #else
1846 static inline void task_numa_fault(int last_node, int node, int pages,
1847 				   int flags)
1848 {
1849 }
1850 static inline pid_t task_numa_group_id(struct task_struct *p)
1851 {
1852 	return 0;
1853 }
1854 static inline void set_numabalancing_state(bool enabled)
1855 {
1856 }
1857 static inline void task_numa_free(struct task_struct *p)
1858 {
1859 }
1860 static inline bool should_numa_migrate_memory(struct task_struct *p,
1861 				struct page *page, int src_nid, int dst_cpu)
1862 {
1863 	return true;
1864 }
1865 #endif
1866 
1867 static inline struct pid *task_pid(struct task_struct *task)
1868 {
1869 	return task->pids[PIDTYPE_PID].pid;
1870 }
1871 
1872 static inline struct pid *task_tgid(struct task_struct *task)
1873 {
1874 	return task->group_leader->pids[PIDTYPE_PID].pid;
1875 }
1876 
1877 /*
1878  * Without tasklist or rcu lock it is not safe to dereference
1879  * the result of task_pgrp/task_session even if task == current,
1880  * we can race with another thread doing sys_setsid/sys_setpgid.
1881  */
1882 static inline struct pid *task_pgrp(struct task_struct *task)
1883 {
1884 	return task->group_leader->pids[PIDTYPE_PGID].pid;
1885 }
1886 
1887 static inline struct pid *task_session(struct task_struct *task)
1888 {
1889 	return task->group_leader->pids[PIDTYPE_SID].pid;
1890 }
1891 
1892 struct pid_namespace;
1893 
1894 /*
1895  * the helpers to get the task's different pids as they are seen
1896  * from various namespaces
1897  *
1898  * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1899  * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1900  *                     current.
1901  * task_xid_nr_ns()  : id seen from the ns specified;
1902  *
1903  * set_task_vxid()   : assigns a virtual id to a task;
1904  *
1905  * see also pid_nr() etc in include/linux/pid.h
1906  */
1907 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1908 			struct pid_namespace *ns);
1909 
1910 static inline pid_t task_pid_nr(struct task_struct *tsk)
1911 {
1912 	return tsk->pid;
1913 }
1914 
1915 static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1916 					struct pid_namespace *ns)
1917 {
1918 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1919 }
1920 
1921 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1922 {
1923 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1924 }
1925 
1926 
1927 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1928 {
1929 	return tsk->tgid;
1930 }
1931 
1932 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1933 
1934 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1935 {
1936 	return pid_vnr(task_tgid(tsk));
1937 }
1938 
1939 
1940 static inline int pid_alive(const struct task_struct *p);
1941 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1942 {
1943 	pid_t pid = 0;
1944 
1945 	rcu_read_lock();
1946 	if (pid_alive(tsk))
1947 		pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1948 	rcu_read_unlock();
1949 
1950 	return pid;
1951 }
1952 
1953 static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1954 {
1955 	return task_ppid_nr_ns(tsk, &init_pid_ns);
1956 }
1957 
1958 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1959 					struct pid_namespace *ns)
1960 {
1961 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1962 }
1963 
1964 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1965 {
1966 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1967 }
1968 
1969 
1970 static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1971 					struct pid_namespace *ns)
1972 {
1973 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1974 }
1975 
1976 static inline pid_t task_session_vnr(struct task_struct *tsk)
1977 {
1978 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1979 }
1980 
1981 /* obsolete, do not use */
1982 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1983 {
1984 	return task_pgrp_nr_ns(tsk, &init_pid_ns);
1985 }
1986 
1987 /**
1988  * pid_alive - check that a task structure is not stale
1989  * @p: Task structure to be checked.
1990  *
1991  * Test if a process is not yet dead (at most zombie state)
1992  * If pid_alive fails, then pointers within the task structure
1993  * can be stale and must not be dereferenced.
1994  *
1995  * Return: 1 if the process is alive. 0 otherwise.
1996  */
1997 static inline int pid_alive(const struct task_struct *p)
1998 {
1999 	return p->pids[PIDTYPE_PID].pid != NULL;
2000 }
2001 
2002 /**
2003  * is_global_init - check if a task structure is init
2004  * @tsk: Task structure to be checked.
2005  *
2006  * Check if a task structure is the first user space task the kernel created.
2007  *
2008  * Return: 1 if the task structure is init. 0 otherwise.
2009  */
2010 static inline int is_global_init(struct task_struct *tsk)
2011 {
2012 	return tsk->pid == 1;
2013 }
2014 
2015 extern struct pid *cad_pid;
2016 
2017 extern void free_task(struct task_struct *tsk);
2018 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
2019 
2020 extern void __put_task_struct(struct task_struct *t);
2021 
2022 static inline void put_task_struct(struct task_struct *t)
2023 {
2024 	if (atomic_dec_and_test(&t->usage))
2025 		__put_task_struct(t);
2026 }
2027 
2028 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
2029 extern void task_cputime(struct task_struct *t,
2030 			 cputime_t *utime, cputime_t *stime);
2031 extern void task_cputime_scaled(struct task_struct *t,
2032 				cputime_t *utimescaled, cputime_t *stimescaled);
2033 extern cputime_t task_gtime(struct task_struct *t);
2034 #else
2035 static inline void task_cputime(struct task_struct *t,
2036 				cputime_t *utime, cputime_t *stime)
2037 {
2038 	if (utime)
2039 		*utime = t->utime;
2040 	if (stime)
2041 		*stime = t->stime;
2042 }
2043 
2044 static inline void task_cputime_scaled(struct task_struct *t,
2045 				       cputime_t *utimescaled,
2046 				       cputime_t *stimescaled)
2047 {
2048 	if (utimescaled)
2049 		*utimescaled = t->utimescaled;
2050 	if (stimescaled)
2051 		*stimescaled = t->stimescaled;
2052 }
2053 
2054 static inline cputime_t task_gtime(struct task_struct *t)
2055 {
2056 	return t->gtime;
2057 }
2058 #endif
2059 extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
2060 extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
2061 
2062 /*
2063  * Per process flags
2064  */
2065 #define PF_EXITING	0x00000004	/* getting shut down */
2066 #define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
2067 #define PF_VCPU		0x00000010	/* I'm a virtual CPU */
2068 #define PF_WQ_WORKER	0x00000020	/* I'm a workqueue worker */
2069 #define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
2070 #define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
2071 #define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
2072 #define PF_DUMPCORE	0x00000200	/* dumped core */
2073 #define PF_SIGNALED	0x00000400	/* killed by a signal */
2074 #define PF_MEMALLOC	0x00000800	/* Allocating memory */
2075 #define PF_NPROC_EXCEEDED 0x00001000	/* set_user noticed that RLIMIT_NPROC was exceeded */
2076 #define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
2077 #define PF_USED_ASYNC	0x00004000	/* used async_schedule*(), used by module init */
2078 #define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
2079 #define PF_FROZEN	0x00010000	/* frozen for system suspend */
2080 #define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
2081 #define PF_KSWAPD	0x00040000	/* I am kswapd */
2082 #define PF_MEMALLOC_NOIO 0x00080000	/* Allocating memory without IO involved */
2083 #define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
2084 #define PF_KTHREAD	0x00200000	/* I am a kernel thread */
2085 #define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
2086 #define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
2087 #define PF_NO_SETAFFINITY 0x04000000	/* Userland is not allowed to meddle with cpus_allowed */
2088 #define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
2089 #define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
2090 #define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezable */
2091 #define PF_SUSPEND_TASK 0x80000000      /* this thread called freeze_processes and should not be frozen */
2092 
2093 /*
2094  * Only the _current_ task can read/write to tsk->flags, but other
2095  * tasks can access tsk->flags in readonly mode for example
2096  * with tsk_used_math (like during threaded core dumping).
2097  * There is however an exception to this rule during ptrace
2098  * or during fork: the ptracer task is allowed to write to the
2099  * child->flags of its traced child (same goes for fork, the parent
2100  * can write to the child->flags), because we're guaranteed the
2101  * child is not running and in turn not changing child->flags
2102  * at the same time the parent does it.
2103  */
2104 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
2105 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
2106 #define clear_used_math() clear_stopped_child_used_math(current)
2107 #define set_used_math() set_stopped_child_used_math(current)
2108 #define conditional_stopped_child_used_math(condition, child) \
2109 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
2110 #define conditional_used_math(condition) \
2111 	conditional_stopped_child_used_math(condition, current)
2112 #define copy_to_stopped_child_used_math(child) \
2113 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
2114 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
2115 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
2116 #define used_math() tsk_used_math(current)
2117 
2118 /* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags
2119  * __GFP_FS is also cleared as it implies __GFP_IO.
2120  */
2121 static inline gfp_t memalloc_noio_flags(gfp_t flags)
2122 {
2123 	if (unlikely(current->flags & PF_MEMALLOC_NOIO))
2124 		flags &= ~(__GFP_IO | __GFP_FS);
2125 	return flags;
2126 }
2127 
2128 static inline unsigned int memalloc_noio_save(void)
2129 {
2130 	unsigned int flags = current->flags & PF_MEMALLOC_NOIO;
2131 	current->flags |= PF_MEMALLOC_NOIO;
2132 	return flags;
2133 }
2134 
2135 static inline void memalloc_noio_restore(unsigned int flags)
2136 {
2137 	current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags;
2138 }
2139 
2140 /* Per-process atomic flags. */
2141 #define PFA_NO_NEW_PRIVS 0	/* May not gain new privileges. */
2142 #define PFA_SPREAD_PAGE  1      /* Spread page cache over cpuset */
2143 #define PFA_SPREAD_SLAB  2      /* Spread some slab caches over cpuset */
2144 
2145 
2146 #define TASK_PFA_TEST(name, func)					\
2147 	static inline bool task_##func(struct task_struct *p)		\
2148 	{ return test_bit(PFA_##name, &p->atomic_flags); }
2149 #define TASK_PFA_SET(name, func)					\
2150 	static inline void task_set_##func(struct task_struct *p)	\
2151 	{ set_bit(PFA_##name, &p->atomic_flags); }
2152 #define TASK_PFA_CLEAR(name, func)					\
2153 	static inline void task_clear_##func(struct task_struct *p)	\
2154 	{ clear_bit(PFA_##name, &p->atomic_flags); }
2155 
2156 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
2157 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
2158 
2159 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
2160 TASK_PFA_SET(SPREAD_PAGE, spread_page)
2161 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
2162 
2163 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
2164 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
2165 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
2166 
2167 /*
2168  * task->jobctl flags
2169  */
2170 #define JOBCTL_STOP_SIGMASK	0xffff	/* signr of the last group stop */
2171 
2172 #define JOBCTL_STOP_DEQUEUED_BIT 16	/* stop signal dequeued */
2173 #define JOBCTL_STOP_PENDING_BIT	17	/* task should stop for group stop */
2174 #define JOBCTL_STOP_CONSUME_BIT	18	/* consume group stop count */
2175 #define JOBCTL_TRAP_STOP_BIT	19	/* trap for STOP */
2176 #define JOBCTL_TRAP_NOTIFY_BIT	20	/* trap for NOTIFY */
2177 #define JOBCTL_TRAPPING_BIT	21	/* switching to TRACED */
2178 #define JOBCTL_LISTENING_BIT	22	/* ptracer is listening for events */
2179 
2180 #define JOBCTL_STOP_DEQUEUED	(1UL << JOBCTL_STOP_DEQUEUED_BIT)
2181 #define JOBCTL_STOP_PENDING	(1UL << JOBCTL_STOP_PENDING_BIT)
2182 #define JOBCTL_STOP_CONSUME	(1UL << JOBCTL_STOP_CONSUME_BIT)
2183 #define JOBCTL_TRAP_STOP	(1UL << JOBCTL_TRAP_STOP_BIT)
2184 #define JOBCTL_TRAP_NOTIFY	(1UL << JOBCTL_TRAP_NOTIFY_BIT)
2185 #define JOBCTL_TRAPPING		(1UL << JOBCTL_TRAPPING_BIT)
2186 #define JOBCTL_LISTENING	(1UL << JOBCTL_LISTENING_BIT)
2187 
2188 #define JOBCTL_TRAP_MASK	(JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY)
2189 #define JOBCTL_PENDING_MASK	(JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK)
2190 
2191 extern bool task_set_jobctl_pending(struct task_struct *task,
2192 				    unsigned long mask);
2193 extern void task_clear_jobctl_trapping(struct task_struct *task);
2194 extern void task_clear_jobctl_pending(struct task_struct *task,
2195 				      unsigned long mask);
2196 
2197 static inline void rcu_copy_process(struct task_struct *p)
2198 {
2199 #ifdef CONFIG_PREEMPT_RCU
2200 	p->rcu_read_lock_nesting = 0;
2201 	p->rcu_read_unlock_special.s = 0;
2202 	p->rcu_blocked_node = NULL;
2203 	INIT_LIST_HEAD(&p->rcu_node_entry);
2204 #endif /* #ifdef CONFIG_PREEMPT_RCU */
2205 #ifdef CONFIG_TASKS_RCU
2206 	p->rcu_tasks_holdout = false;
2207 	INIT_LIST_HEAD(&p->rcu_tasks_holdout_list);
2208 	p->rcu_tasks_idle_cpu = -1;
2209 #endif /* #ifdef CONFIG_TASKS_RCU */
2210 }
2211 
2212 static inline void tsk_restore_flags(struct task_struct *task,
2213 				unsigned long orig_flags, unsigned long flags)
2214 {
2215 	task->flags &= ~flags;
2216 	task->flags |= orig_flags & flags;
2217 }
2218 
2219 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur,
2220 				     const struct cpumask *trial);
2221 extern int task_can_attach(struct task_struct *p,
2222 			   const struct cpumask *cs_cpus_allowed);
2223 #ifdef CONFIG_SMP
2224 extern void do_set_cpus_allowed(struct task_struct *p,
2225 			       const struct cpumask *new_mask);
2226 
2227 extern int set_cpus_allowed_ptr(struct task_struct *p,
2228 				const struct cpumask *new_mask);
2229 #else
2230 static inline void do_set_cpus_allowed(struct task_struct *p,
2231 				      const struct cpumask *new_mask)
2232 {
2233 }
2234 static inline int set_cpus_allowed_ptr(struct task_struct *p,
2235 				       const struct cpumask *new_mask)
2236 {
2237 	if (!cpumask_test_cpu(0, new_mask))
2238 		return -EINVAL;
2239 	return 0;
2240 }
2241 #endif
2242 
2243 #ifdef CONFIG_NO_HZ_COMMON
2244 void calc_load_enter_idle(void);
2245 void calc_load_exit_idle(void);
2246 #else
2247 static inline void calc_load_enter_idle(void) { }
2248 static inline void calc_load_exit_idle(void) { }
2249 #endif /* CONFIG_NO_HZ_COMMON */
2250 
2251 /*
2252  * Do not use outside of architecture code which knows its limitations.
2253  *
2254  * sched_clock() has no promise of monotonicity or bounded drift between
2255  * CPUs, use (which you should not) requires disabling IRQs.
2256  *
2257  * Please use one of the three interfaces below.
2258  */
2259 extern unsigned long long notrace sched_clock(void);
2260 /*
2261  * See the comment in kernel/sched/clock.c
2262  */
2263 extern u64 cpu_clock(int cpu);
2264 extern u64 local_clock(void);
2265 extern u64 running_clock(void);
2266 extern u64 sched_clock_cpu(int cpu);
2267 
2268 
2269 extern void sched_clock_init(void);
2270 
2271 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
2272 static inline void sched_clock_tick(void)
2273 {
2274 }
2275 
2276 static inline void sched_clock_idle_sleep_event(void)
2277 {
2278 }
2279 
2280 static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
2281 {
2282 }
2283 #else
2284 /*
2285  * Architectures can set this to 1 if they have specified
2286  * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
2287  * but then during bootup it turns out that sched_clock()
2288  * is reliable after all:
2289  */
2290 extern int sched_clock_stable(void);
2291 extern void set_sched_clock_stable(void);
2292 extern void clear_sched_clock_stable(void);
2293 
2294 extern void sched_clock_tick(void);
2295 extern void sched_clock_idle_sleep_event(void);
2296 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2297 #endif
2298 
2299 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2300 /*
2301  * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
2302  * The reason for this explicit opt-in is not to have perf penalty with
2303  * slow sched_clocks.
2304  */
2305 extern void enable_sched_clock_irqtime(void);
2306 extern void disable_sched_clock_irqtime(void);
2307 #else
2308 static inline void enable_sched_clock_irqtime(void) {}
2309 static inline void disable_sched_clock_irqtime(void) {}
2310 #endif
2311 
2312 extern unsigned long long
2313 task_sched_runtime(struct task_struct *task);
2314 
2315 /* sched_exec is called by processes performing an exec */
2316 #ifdef CONFIG_SMP
2317 extern void sched_exec(void);
2318 #else
2319 #define sched_exec()   {}
2320 #endif
2321 
2322 extern void sched_clock_idle_sleep_event(void);
2323 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2324 
2325 #ifdef CONFIG_HOTPLUG_CPU
2326 extern void idle_task_exit(void);
2327 #else
2328 static inline void idle_task_exit(void) {}
2329 #endif
2330 
2331 #if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
2332 extern void wake_up_nohz_cpu(int cpu);
2333 #else
2334 static inline void wake_up_nohz_cpu(int cpu) { }
2335 #endif
2336 
2337 #ifdef CONFIG_NO_HZ_FULL
2338 extern bool sched_can_stop_tick(void);
2339 extern u64 scheduler_tick_max_deferment(void);
2340 #else
2341 static inline bool sched_can_stop_tick(void) { return false; }
2342 #endif
2343 
2344 #ifdef CONFIG_SCHED_AUTOGROUP
2345 extern void sched_autogroup_create_attach(struct task_struct *p);
2346 extern void sched_autogroup_detach(struct task_struct *p);
2347 extern void sched_autogroup_fork(struct signal_struct *sig);
2348 extern void sched_autogroup_exit(struct signal_struct *sig);
2349 #ifdef CONFIG_PROC_FS
2350 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
2351 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice);
2352 #endif
2353 #else
2354 static inline void sched_autogroup_create_attach(struct task_struct *p) { }
2355 static inline void sched_autogroup_detach(struct task_struct *p) { }
2356 static inline void sched_autogroup_fork(struct signal_struct *sig) { }
2357 static inline void sched_autogroup_exit(struct signal_struct *sig) { }
2358 #endif
2359 
2360 extern int yield_to(struct task_struct *p, bool preempt);
2361 extern void set_user_nice(struct task_struct *p, long nice);
2362 extern int task_prio(const struct task_struct *p);
2363 /**
2364  * task_nice - return the nice value of a given task.
2365  * @p: the task in question.
2366  *
2367  * Return: The nice value [ -20 ... 0 ... 19 ].
2368  */
2369 static inline int task_nice(const struct task_struct *p)
2370 {
2371 	return PRIO_TO_NICE((p)->static_prio);
2372 }
2373 extern int can_nice(const struct task_struct *p, const int nice);
2374 extern int task_curr(const struct task_struct *p);
2375 extern int idle_cpu(int cpu);
2376 extern int sched_setscheduler(struct task_struct *, int,
2377 			      const struct sched_param *);
2378 extern int sched_setscheduler_nocheck(struct task_struct *, int,
2379 				      const struct sched_param *);
2380 extern int sched_setattr(struct task_struct *,
2381 			 const struct sched_attr *);
2382 extern struct task_struct *idle_task(int cpu);
2383 /**
2384  * is_idle_task - is the specified task an idle task?
2385  * @p: the task in question.
2386  *
2387  * Return: 1 if @p is an idle task. 0 otherwise.
2388  */
2389 static inline bool is_idle_task(const struct task_struct *p)
2390 {
2391 	return p->pid == 0;
2392 }
2393 extern struct task_struct *curr_task(int cpu);
2394 extern void set_curr_task(int cpu, struct task_struct *p);
2395 
2396 void yield(void);
2397 
2398 union thread_union {
2399 	struct thread_info thread_info;
2400 	unsigned long stack[THREAD_SIZE/sizeof(long)];
2401 };
2402 
2403 #ifndef __HAVE_ARCH_KSTACK_END
2404 static inline int kstack_end(void *addr)
2405 {
2406 	/* Reliable end of stack detection:
2407 	 * Some APM bios versions misalign the stack
2408 	 */
2409 	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
2410 }
2411 #endif
2412 
2413 extern union thread_union init_thread_union;
2414 extern struct task_struct init_task;
2415 
2416 extern struct   mm_struct init_mm;
2417 
2418 extern struct pid_namespace init_pid_ns;
2419 
2420 /*
2421  * find a task by one of its numerical ids
2422  *
2423  * find_task_by_pid_ns():
2424  *      finds a task by its pid in the specified namespace
2425  * find_task_by_vpid():
2426  *      finds a task by its virtual pid
2427  *
2428  * see also find_vpid() etc in include/linux/pid.h
2429  */
2430 
2431 extern struct task_struct *find_task_by_vpid(pid_t nr);
2432 extern struct task_struct *find_task_by_pid_ns(pid_t nr,
2433 		struct pid_namespace *ns);
2434 
2435 /* per-UID process charging. */
2436 extern struct user_struct * alloc_uid(kuid_t);
2437 static inline struct user_struct *get_uid(struct user_struct *u)
2438 {
2439 	atomic_inc(&u->__count);
2440 	return u;
2441 }
2442 extern void free_uid(struct user_struct *);
2443 
2444 #include <asm/current.h>
2445 
2446 extern void xtime_update(unsigned long ticks);
2447 
2448 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2449 extern int wake_up_process(struct task_struct *tsk);
2450 extern void wake_up_new_task(struct task_struct *tsk);
2451 #ifdef CONFIG_SMP
2452  extern void kick_process(struct task_struct *tsk);
2453 #else
2454  static inline void kick_process(struct task_struct *tsk) { }
2455 #endif
2456 extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
2457 extern void sched_dead(struct task_struct *p);
2458 
2459 extern void proc_caches_init(void);
2460 extern void flush_signals(struct task_struct *);
2461 extern void ignore_signals(struct task_struct *);
2462 extern void flush_signal_handlers(struct task_struct *, int force_default);
2463 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2464 
2465 static inline int kernel_dequeue_signal(siginfo_t *info)
2466 {
2467 	struct task_struct *tsk = current;
2468 	siginfo_t __info;
2469 	int ret;
2470 
2471 	spin_lock_irq(&tsk->sighand->siglock);
2472 	ret = dequeue_signal(tsk, &tsk->blocked, info ?: &__info);
2473 	spin_unlock_irq(&tsk->sighand->siglock);
2474 
2475 	return ret;
2476 }
2477 
2478 static inline void kernel_signal_stop(void)
2479 {
2480 	spin_lock_irq(&current->sighand->siglock);
2481 	if (current->jobctl & JOBCTL_STOP_DEQUEUED)
2482 		__set_current_state(TASK_STOPPED);
2483 	spin_unlock_irq(&current->sighand->siglock);
2484 
2485 	schedule();
2486 }
2487 
2488 extern void release_task(struct task_struct * p);
2489 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2490 extern int force_sigsegv(int, struct task_struct *);
2491 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2492 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2493 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2494 extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *,
2495 				const struct cred *, u32);
2496 extern int kill_pgrp(struct pid *pid, int sig, int priv);
2497 extern int kill_pid(struct pid *pid, int sig, int priv);
2498 extern int kill_proc_info(int, struct siginfo *, pid_t);
2499 extern __must_check bool do_notify_parent(struct task_struct *, int);
2500 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2501 extern void force_sig(int, struct task_struct *);
2502 extern int send_sig(int, struct task_struct *, int);
2503 extern int zap_other_threads(struct task_struct *p);
2504 extern struct sigqueue *sigqueue_alloc(void);
2505 extern void sigqueue_free(struct sigqueue *);
2506 extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
2507 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2508 
2509 static inline void restore_saved_sigmask(void)
2510 {
2511 	if (test_and_clear_restore_sigmask())
2512 		__set_current_blocked(&current->saved_sigmask);
2513 }
2514 
2515 static inline sigset_t *sigmask_to_save(void)
2516 {
2517 	sigset_t *res = &current->blocked;
2518 	if (unlikely(test_restore_sigmask()))
2519 		res = &current->saved_sigmask;
2520 	return res;
2521 }
2522 
2523 static inline int kill_cad_pid(int sig, int priv)
2524 {
2525 	return kill_pid(cad_pid, sig, priv);
2526 }
2527 
2528 /* These can be the second arg to send_sig_info/send_group_sig_info.  */
2529 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
2530 #define SEND_SIG_PRIV	((struct siginfo *) 1)
2531 #define SEND_SIG_FORCED	((struct siginfo *) 2)
2532 
2533 /*
2534  * True if we are on the alternate signal stack.
2535  */
2536 static inline int on_sig_stack(unsigned long sp)
2537 {
2538 #ifdef CONFIG_STACK_GROWSUP
2539 	return sp >= current->sas_ss_sp &&
2540 		sp - current->sas_ss_sp < current->sas_ss_size;
2541 #else
2542 	return sp > current->sas_ss_sp &&
2543 		sp - current->sas_ss_sp <= current->sas_ss_size;
2544 #endif
2545 }
2546 
2547 static inline int sas_ss_flags(unsigned long sp)
2548 {
2549 	if (!current->sas_ss_size)
2550 		return SS_DISABLE;
2551 
2552 	return on_sig_stack(sp) ? SS_ONSTACK : 0;
2553 }
2554 
2555 static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig)
2556 {
2557 	if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp))
2558 #ifdef CONFIG_STACK_GROWSUP
2559 		return current->sas_ss_sp;
2560 #else
2561 		return current->sas_ss_sp + current->sas_ss_size;
2562 #endif
2563 	return sp;
2564 }
2565 
2566 /*
2567  * Routines for handling mm_structs
2568  */
2569 extern struct mm_struct * mm_alloc(void);
2570 
2571 /* mmdrop drops the mm and the page tables */
2572 extern void __mmdrop(struct mm_struct *);
2573 static inline void mmdrop(struct mm_struct * mm)
2574 {
2575 	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2576 		__mmdrop(mm);
2577 }
2578 
2579 /* mmput gets rid of the mappings and all user-space */
2580 extern void mmput(struct mm_struct *);
2581 /* Grab a reference to a task's mm, if it is not already going away */
2582 extern struct mm_struct *get_task_mm(struct task_struct *task);
2583 /*
2584  * Grab a reference to a task's mm, if it is not already going away
2585  * and ptrace_may_access with the mode parameter passed to it
2586  * succeeds.
2587  */
2588 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode);
2589 /* Remove the current tasks stale references to the old mm_struct */
2590 extern void mm_release(struct task_struct *, struct mm_struct *);
2591 
2592 #ifdef CONFIG_HAVE_COPY_THREAD_TLS
2593 extern int copy_thread_tls(unsigned long, unsigned long, unsigned long,
2594 			struct task_struct *, unsigned long);
2595 #else
2596 extern int copy_thread(unsigned long, unsigned long, unsigned long,
2597 			struct task_struct *);
2598 
2599 /* Architectures that haven't opted into copy_thread_tls get the tls argument
2600  * via pt_regs, so ignore the tls argument passed via C. */
2601 static inline int copy_thread_tls(
2602 		unsigned long clone_flags, unsigned long sp, unsigned long arg,
2603 		struct task_struct *p, unsigned long tls)
2604 {
2605 	return copy_thread(clone_flags, sp, arg, p);
2606 }
2607 #endif
2608 extern void flush_thread(void);
2609 extern void exit_thread(void);
2610 
2611 extern void exit_files(struct task_struct *);
2612 extern void __cleanup_sighand(struct sighand_struct *);
2613 
2614 extern void exit_itimers(struct signal_struct *);
2615 extern void flush_itimer_signals(void);
2616 
2617 extern void do_group_exit(int);
2618 
2619 extern int do_execve(struct filename *,
2620 		     const char __user * const __user *,
2621 		     const char __user * const __user *);
2622 extern int do_execveat(int, struct filename *,
2623 		       const char __user * const __user *,
2624 		       const char __user * const __user *,
2625 		       int);
2626 extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long);
2627 extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
2628 struct task_struct *fork_idle(int);
2629 extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
2630 
2631 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
2632 static inline void set_task_comm(struct task_struct *tsk, const char *from)
2633 {
2634 	__set_task_comm(tsk, from, false);
2635 }
2636 extern char *get_task_comm(char *to, struct task_struct *tsk);
2637 
2638 #ifdef CONFIG_SMP
2639 void scheduler_ipi(void);
2640 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2641 #else
2642 static inline void scheduler_ipi(void) { }
2643 static inline unsigned long wait_task_inactive(struct task_struct *p,
2644 					       long match_state)
2645 {
2646 	return 1;
2647 }
2648 #endif
2649 
2650 #define tasklist_empty() \
2651 	list_empty(&init_task.tasks)
2652 
2653 #define next_task(p) \
2654 	list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2655 
2656 #define for_each_process(p) \
2657 	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2658 
2659 extern bool current_is_single_threaded(void);
2660 
2661 /*
2662  * Careful: do_each_thread/while_each_thread is a double loop so
2663  *          'break' will not work as expected - use goto instead.
2664  */
2665 #define do_each_thread(g, t) \
2666 	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2667 
2668 #define while_each_thread(g, t) \
2669 	while ((t = next_thread(t)) != g)
2670 
2671 #define __for_each_thread(signal, t)	\
2672 	list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node)
2673 
2674 #define for_each_thread(p, t)		\
2675 	__for_each_thread((p)->signal, t)
2676 
2677 /* Careful: this is a double loop, 'break' won't work as expected. */
2678 #define for_each_process_thread(p, t)	\
2679 	for_each_process(p) for_each_thread(p, t)
2680 
2681 static inline int get_nr_threads(struct task_struct *tsk)
2682 {
2683 	return tsk->signal->nr_threads;
2684 }
2685 
2686 static inline bool thread_group_leader(struct task_struct *p)
2687 {
2688 	return p->exit_signal >= 0;
2689 }
2690 
2691 /* Do to the insanities of de_thread it is possible for a process
2692  * to have the pid of the thread group leader without actually being
2693  * the thread group leader.  For iteration through the pids in proc
2694  * all we care about is that we have a task with the appropriate
2695  * pid, we don't actually care if we have the right task.
2696  */
2697 static inline bool has_group_leader_pid(struct task_struct *p)
2698 {
2699 	return task_pid(p) == p->signal->leader_pid;
2700 }
2701 
2702 static inline
2703 bool same_thread_group(struct task_struct *p1, struct task_struct *p2)
2704 {
2705 	return p1->signal == p2->signal;
2706 }
2707 
2708 static inline struct task_struct *next_thread(const struct task_struct *p)
2709 {
2710 	return list_entry_rcu(p->thread_group.next,
2711 			      struct task_struct, thread_group);
2712 }
2713 
2714 static inline int thread_group_empty(struct task_struct *p)
2715 {
2716 	return list_empty(&p->thread_group);
2717 }
2718 
2719 #define delay_group_leader(p) \
2720 		(thread_group_leader(p) && !thread_group_empty(p))
2721 
2722 /*
2723  * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2724  * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2725  * pins the final release of task.io_context.  Also protects ->cpuset and
2726  * ->cgroup.subsys[]. And ->vfork_done.
2727  *
2728  * Nests both inside and outside of read_lock(&tasklist_lock).
2729  * It must not be nested with write_lock_irq(&tasklist_lock),
2730  * neither inside nor outside.
2731  */
2732 static inline void task_lock(struct task_struct *p)
2733 {
2734 	spin_lock(&p->alloc_lock);
2735 }
2736 
2737 static inline void task_unlock(struct task_struct *p)
2738 {
2739 	spin_unlock(&p->alloc_lock);
2740 }
2741 
2742 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2743 							unsigned long *flags);
2744 
2745 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2746 						       unsigned long *flags)
2747 {
2748 	struct sighand_struct *ret;
2749 
2750 	ret = __lock_task_sighand(tsk, flags);
2751 	(void)__cond_lock(&tsk->sighand->siglock, ret);
2752 	return ret;
2753 }
2754 
2755 static inline void unlock_task_sighand(struct task_struct *tsk,
2756 						unsigned long *flags)
2757 {
2758 	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2759 }
2760 
2761 /**
2762  * threadgroup_change_begin - mark the beginning of changes to a threadgroup
2763  * @tsk: task causing the changes
2764  *
2765  * All operations which modify a threadgroup - a new thread joining the
2766  * group, death of a member thread (the assertion of PF_EXITING) and
2767  * exec(2) dethreading the process and replacing the leader - are wrapped
2768  * by threadgroup_change_{begin|end}().  This is to provide a place which
2769  * subsystems needing threadgroup stability can hook into for
2770  * synchronization.
2771  */
2772 static inline void threadgroup_change_begin(struct task_struct *tsk)
2773 {
2774 	might_sleep();
2775 	cgroup_threadgroup_change_begin(tsk);
2776 }
2777 
2778 /**
2779  * threadgroup_change_end - mark the end of changes to a threadgroup
2780  * @tsk: task causing the changes
2781  *
2782  * See threadgroup_change_begin().
2783  */
2784 static inline void threadgroup_change_end(struct task_struct *tsk)
2785 {
2786 	cgroup_threadgroup_change_end(tsk);
2787 }
2788 
2789 #ifndef __HAVE_THREAD_FUNCTIONS
2790 
2791 #define task_thread_info(task)	((struct thread_info *)(task)->stack)
2792 #define task_stack_page(task)	((task)->stack)
2793 
2794 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2795 {
2796 	*task_thread_info(p) = *task_thread_info(org);
2797 	task_thread_info(p)->task = p;
2798 }
2799 
2800 /*
2801  * Return the address of the last usable long on the stack.
2802  *
2803  * When the stack grows down, this is just above the thread
2804  * info struct. Going any lower will corrupt the threadinfo.
2805  *
2806  * When the stack grows up, this is the highest address.
2807  * Beyond that position, we corrupt data on the next page.
2808  */
2809 static inline unsigned long *end_of_stack(struct task_struct *p)
2810 {
2811 #ifdef CONFIG_STACK_GROWSUP
2812 	return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1;
2813 #else
2814 	return (unsigned long *)(task_thread_info(p) + 1);
2815 #endif
2816 }
2817 
2818 #endif
2819 #define task_stack_end_corrupted(task) \
2820 		(*(end_of_stack(task)) != STACK_END_MAGIC)
2821 
2822 static inline int object_is_on_stack(void *obj)
2823 {
2824 	void *stack = task_stack_page(current);
2825 
2826 	return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2827 }
2828 
2829 extern void thread_info_cache_init(void);
2830 
2831 #ifdef CONFIG_DEBUG_STACK_USAGE
2832 static inline unsigned long stack_not_used(struct task_struct *p)
2833 {
2834 	unsigned long *n = end_of_stack(p);
2835 
2836 	do { 	/* Skip over canary */
2837 		n++;
2838 	} while (!*n);
2839 
2840 	return (unsigned long)n - (unsigned long)end_of_stack(p);
2841 }
2842 #endif
2843 extern void set_task_stack_end_magic(struct task_struct *tsk);
2844 
2845 /* set thread flags in other task's structures
2846  * - see asm/thread_info.h for TIF_xxxx flags available
2847  */
2848 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2849 {
2850 	set_ti_thread_flag(task_thread_info(tsk), flag);
2851 }
2852 
2853 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2854 {
2855 	clear_ti_thread_flag(task_thread_info(tsk), flag);
2856 }
2857 
2858 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2859 {
2860 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2861 }
2862 
2863 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2864 {
2865 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2866 }
2867 
2868 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2869 {
2870 	return test_ti_thread_flag(task_thread_info(tsk), flag);
2871 }
2872 
2873 static inline void set_tsk_need_resched(struct task_struct *tsk)
2874 {
2875 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2876 }
2877 
2878 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2879 {
2880 	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2881 }
2882 
2883 static inline int test_tsk_need_resched(struct task_struct *tsk)
2884 {
2885 	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2886 }
2887 
2888 static inline int restart_syscall(void)
2889 {
2890 	set_tsk_thread_flag(current, TIF_SIGPENDING);
2891 	return -ERESTARTNOINTR;
2892 }
2893 
2894 static inline int signal_pending(struct task_struct *p)
2895 {
2896 	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2897 }
2898 
2899 static inline int __fatal_signal_pending(struct task_struct *p)
2900 {
2901 	return unlikely(sigismember(&p->pending.signal, SIGKILL));
2902 }
2903 
2904 static inline int fatal_signal_pending(struct task_struct *p)
2905 {
2906 	return signal_pending(p) && __fatal_signal_pending(p);
2907 }
2908 
2909 static inline int signal_pending_state(long state, struct task_struct *p)
2910 {
2911 	if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2912 		return 0;
2913 	if (!signal_pending(p))
2914 		return 0;
2915 
2916 	return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2917 }
2918 
2919 /*
2920  * cond_resched() and cond_resched_lock(): latency reduction via
2921  * explicit rescheduling in places that are safe. The return
2922  * value indicates whether a reschedule was done in fact.
2923  * cond_resched_lock() will drop the spinlock before scheduling,
2924  * cond_resched_softirq() will enable bhs before scheduling.
2925  */
2926 extern int _cond_resched(void);
2927 
2928 #define cond_resched() ({			\
2929 	___might_sleep(__FILE__, __LINE__, 0);	\
2930 	_cond_resched();			\
2931 })
2932 
2933 extern int __cond_resched_lock(spinlock_t *lock);
2934 
2935 #define cond_resched_lock(lock) ({				\
2936 	___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
2937 	__cond_resched_lock(lock);				\
2938 })
2939 
2940 extern int __cond_resched_softirq(void);
2941 
2942 #define cond_resched_softirq() ({					\
2943 	___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET);	\
2944 	__cond_resched_softirq();					\
2945 })
2946 
2947 static inline void cond_resched_rcu(void)
2948 {
2949 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
2950 	rcu_read_unlock();
2951 	cond_resched();
2952 	rcu_read_lock();
2953 #endif
2954 }
2955 
2956 /*
2957  * Does a critical section need to be broken due to another
2958  * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2959  * but a general need for low latency)
2960  */
2961 static inline int spin_needbreak(spinlock_t *lock)
2962 {
2963 #ifdef CONFIG_PREEMPT
2964 	return spin_is_contended(lock);
2965 #else
2966 	return 0;
2967 #endif
2968 }
2969 
2970 /*
2971  * Idle thread specific functions to determine the need_resched
2972  * polling state.
2973  */
2974 #ifdef TIF_POLLING_NRFLAG
2975 static inline int tsk_is_polling(struct task_struct *p)
2976 {
2977 	return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG);
2978 }
2979 
2980 static inline void __current_set_polling(void)
2981 {
2982 	set_thread_flag(TIF_POLLING_NRFLAG);
2983 }
2984 
2985 static inline bool __must_check current_set_polling_and_test(void)
2986 {
2987 	__current_set_polling();
2988 
2989 	/*
2990 	 * Polling state must be visible before we test NEED_RESCHED,
2991 	 * paired by resched_curr()
2992 	 */
2993 	smp_mb__after_atomic();
2994 
2995 	return unlikely(tif_need_resched());
2996 }
2997 
2998 static inline void __current_clr_polling(void)
2999 {
3000 	clear_thread_flag(TIF_POLLING_NRFLAG);
3001 }
3002 
3003 static inline bool __must_check current_clr_polling_and_test(void)
3004 {
3005 	__current_clr_polling();
3006 
3007 	/*
3008 	 * Polling state must be visible before we test NEED_RESCHED,
3009 	 * paired by resched_curr()
3010 	 */
3011 	smp_mb__after_atomic();
3012 
3013 	return unlikely(tif_need_resched());
3014 }
3015 
3016 #else
3017 static inline int tsk_is_polling(struct task_struct *p) { return 0; }
3018 static inline void __current_set_polling(void) { }
3019 static inline void __current_clr_polling(void) { }
3020 
3021 static inline bool __must_check current_set_polling_and_test(void)
3022 {
3023 	return unlikely(tif_need_resched());
3024 }
3025 static inline bool __must_check current_clr_polling_and_test(void)
3026 {
3027 	return unlikely(tif_need_resched());
3028 }
3029 #endif
3030 
3031 static inline void current_clr_polling(void)
3032 {
3033 	__current_clr_polling();
3034 
3035 	/*
3036 	 * Ensure we check TIF_NEED_RESCHED after we clear the polling bit.
3037 	 * Once the bit is cleared, we'll get IPIs with every new
3038 	 * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also
3039 	 * fold.
3040 	 */
3041 	smp_mb(); /* paired with resched_curr() */
3042 
3043 	preempt_fold_need_resched();
3044 }
3045 
3046 static __always_inline bool need_resched(void)
3047 {
3048 	return unlikely(tif_need_resched());
3049 }
3050 
3051 /*
3052  * Thread group CPU time accounting.
3053  */
3054 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
3055 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
3056 
3057 /*
3058  * Reevaluate whether the task has signals pending delivery.
3059  * Wake the task if so.
3060  * This is required every time the blocked sigset_t changes.
3061  * callers must hold sighand->siglock.
3062  */
3063 extern void recalc_sigpending_and_wake(struct task_struct *t);
3064 extern void recalc_sigpending(void);
3065 
3066 extern void signal_wake_up_state(struct task_struct *t, unsigned int state);
3067 
3068 static inline void signal_wake_up(struct task_struct *t, bool resume)
3069 {
3070 	signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
3071 }
3072 static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
3073 {
3074 	signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
3075 }
3076 
3077 /*
3078  * Wrappers for p->thread_info->cpu access. No-op on UP.
3079  */
3080 #ifdef CONFIG_SMP
3081 
3082 static inline unsigned int task_cpu(const struct task_struct *p)
3083 {
3084 	return task_thread_info(p)->cpu;
3085 }
3086 
3087 static inline int task_node(const struct task_struct *p)
3088 {
3089 	return cpu_to_node(task_cpu(p));
3090 }
3091 
3092 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
3093 
3094 #else
3095 
3096 static inline unsigned int task_cpu(const struct task_struct *p)
3097 {
3098 	return 0;
3099 }
3100 
3101 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
3102 {
3103 }
3104 
3105 #endif /* CONFIG_SMP */
3106 
3107 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
3108 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
3109 
3110 #ifdef CONFIG_CGROUP_SCHED
3111 extern struct task_group root_task_group;
3112 #endif /* CONFIG_CGROUP_SCHED */
3113 
3114 extern int task_can_switch_user(struct user_struct *up,
3115 					struct task_struct *tsk);
3116 
3117 #ifdef CONFIG_TASK_XACCT
3118 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3119 {
3120 	tsk->ioac.rchar += amt;
3121 }
3122 
3123 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3124 {
3125 	tsk->ioac.wchar += amt;
3126 }
3127 
3128 static inline void inc_syscr(struct task_struct *tsk)
3129 {
3130 	tsk->ioac.syscr++;
3131 }
3132 
3133 static inline void inc_syscw(struct task_struct *tsk)
3134 {
3135 	tsk->ioac.syscw++;
3136 }
3137 #else
3138 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3139 {
3140 }
3141 
3142 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3143 {
3144 }
3145 
3146 static inline void inc_syscr(struct task_struct *tsk)
3147 {
3148 }
3149 
3150 static inline void inc_syscw(struct task_struct *tsk)
3151 {
3152 }
3153 #endif
3154 
3155 #ifndef TASK_SIZE_OF
3156 #define TASK_SIZE_OF(tsk)	TASK_SIZE
3157 #endif
3158 
3159 #ifdef CONFIG_MEMCG
3160 extern void mm_update_next_owner(struct mm_struct *mm);
3161 #else
3162 static inline void mm_update_next_owner(struct mm_struct *mm)
3163 {
3164 }
3165 #endif /* CONFIG_MEMCG */
3166 
3167 static inline unsigned long task_rlimit(const struct task_struct *tsk,
3168 		unsigned int limit)
3169 {
3170 	return READ_ONCE(tsk->signal->rlim[limit].rlim_cur);
3171 }
3172 
3173 static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
3174 		unsigned int limit)
3175 {
3176 	return READ_ONCE(tsk->signal->rlim[limit].rlim_max);
3177 }
3178 
3179 static inline unsigned long rlimit(unsigned int limit)
3180 {
3181 	return task_rlimit(current, limit);
3182 }
3183 
3184 static inline unsigned long rlimit_max(unsigned int limit)
3185 {
3186 	return task_rlimit_max(current, limit);
3187 }
3188 
3189 #endif
3190