xref: /linux/include/linux/sched.h (revision 9cfc5c90ad38c8fc11bfd39de42a107da00871ba)
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 #define MMF_DUMP_DAX_PRIVATE	9
488 #define MMF_DUMP_DAX_SHARED	10
489 
490 #define MMF_DUMP_FILTER_SHIFT	MMF_DUMPABLE_BITS
491 #define MMF_DUMP_FILTER_BITS	9
492 #define MMF_DUMP_FILTER_MASK \
493 	(((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
494 #define MMF_DUMP_FILTER_DEFAULT \
495 	((1 << MMF_DUMP_ANON_PRIVATE) |	(1 << MMF_DUMP_ANON_SHARED) |\
496 	 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
497 
498 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
499 # define MMF_DUMP_MASK_DEFAULT_ELF	(1 << MMF_DUMP_ELF_HEADERS)
500 #else
501 # define MMF_DUMP_MASK_DEFAULT_ELF	0
502 #endif
503 					/* leave room for more dump flags */
504 #define MMF_VM_MERGEABLE	16	/* KSM may merge identical pages */
505 #define MMF_VM_HUGEPAGE		17	/* set when VM_HUGEPAGE is set on vma */
506 #define MMF_EXE_FILE_CHANGED	18	/* see prctl_set_mm_exe_file() */
507 
508 #define MMF_HAS_UPROBES		19	/* has uprobes */
509 #define MMF_RECALC_UPROBES	20	/* MMF_HAS_UPROBES can be wrong */
510 
511 #define MMF_INIT_MASK		(MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
512 
513 struct sighand_struct {
514 	atomic_t		count;
515 	struct k_sigaction	action[_NSIG];
516 	spinlock_t		siglock;
517 	wait_queue_head_t	signalfd_wqh;
518 };
519 
520 struct pacct_struct {
521 	int			ac_flag;
522 	long			ac_exitcode;
523 	unsigned long		ac_mem;
524 	cputime_t		ac_utime, ac_stime;
525 	unsigned long		ac_minflt, ac_majflt;
526 };
527 
528 struct cpu_itimer {
529 	cputime_t expires;
530 	cputime_t incr;
531 	u32 error;
532 	u32 incr_error;
533 };
534 
535 /**
536  * struct prev_cputime - snaphsot of system and user cputime
537  * @utime: time spent in user mode
538  * @stime: time spent in system mode
539  * @lock: protects the above two fields
540  *
541  * Stores previous user/system time values such that we can guarantee
542  * monotonicity.
543  */
544 struct prev_cputime {
545 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
546 	cputime_t utime;
547 	cputime_t stime;
548 	raw_spinlock_t lock;
549 #endif
550 };
551 
552 static inline void prev_cputime_init(struct prev_cputime *prev)
553 {
554 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
555 	prev->utime = prev->stime = 0;
556 	raw_spin_lock_init(&prev->lock);
557 #endif
558 }
559 
560 /**
561  * struct task_cputime - collected CPU time counts
562  * @utime:		time spent in user mode, in &cputime_t units
563  * @stime:		time spent in kernel mode, in &cputime_t units
564  * @sum_exec_runtime:	total time spent on the CPU, in nanoseconds
565  *
566  * This structure groups together three kinds of CPU time that are tracked for
567  * threads and thread groups.  Most things considering CPU time want to group
568  * these counts together and treat all three of them in parallel.
569  */
570 struct task_cputime {
571 	cputime_t utime;
572 	cputime_t stime;
573 	unsigned long long sum_exec_runtime;
574 };
575 
576 /* Alternate field names when used to cache expirations. */
577 #define virt_exp	utime
578 #define prof_exp	stime
579 #define sched_exp	sum_exec_runtime
580 
581 #define INIT_CPUTIME	\
582 	(struct task_cputime) {					\
583 		.utime = 0,					\
584 		.stime = 0,					\
585 		.sum_exec_runtime = 0,				\
586 	}
587 
588 /*
589  * This is the atomic variant of task_cputime, which can be used for
590  * storing and updating task_cputime statistics without locking.
591  */
592 struct task_cputime_atomic {
593 	atomic64_t utime;
594 	atomic64_t stime;
595 	atomic64_t sum_exec_runtime;
596 };
597 
598 #define INIT_CPUTIME_ATOMIC \
599 	(struct task_cputime_atomic) {				\
600 		.utime = ATOMIC64_INIT(0),			\
601 		.stime = ATOMIC64_INIT(0),			\
602 		.sum_exec_runtime = ATOMIC64_INIT(0),		\
603 	}
604 
605 #define PREEMPT_DISABLED	(PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
606 
607 /*
608  * Disable preemption until the scheduler is running -- use an unconditional
609  * value so that it also works on !PREEMPT_COUNT kernels.
610  *
611  * Reset by start_kernel()->sched_init()->init_idle()->init_idle_preempt_count().
612  */
613 #define INIT_PREEMPT_COUNT	PREEMPT_OFFSET
614 
615 /*
616  * Initial preempt_count value; reflects the preempt_count schedule invariant
617  * which states that during context switches:
618  *
619  *    preempt_count() == 2*PREEMPT_DISABLE_OFFSET
620  *
621  * Note: PREEMPT_DISABLE_OFFSET is 0 for !PREEMPT_COUNT kernels.
622  * Note: See finish_task_switch().
623  */
624 #define FORK_PREEMPT_COUNT	(2*PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
625 
626 /**
627  * struct thread_group_cputimer - thread group interval timer counts
628  * @cputime_atomic:	atomic thread group interval timers.
629  * @running:		true when there are timers running and
630  *			@cputime_atomic receives updates.
631  * @checking_timer:	true when a thread in the group is in the
632  *			process of checking for thread group timers.
633  *
634  * This structure contains the version of task_cputime, above, that is
635  * used for thread group CPU timer calculations.
636  */
637 struct thread_group_cputimer {
638 	struct task_cputime_atomic cputime_atomic;
639 	bool running;
640 	bool checking_timer;
641 };
642 
643 #include <linux/rwsem.h>
644 struct autogroup;
645 
646 /*
647  * NOTE! "signal_struct" does not have its own
648  * locking, because a shared signal_struct always
649  * implies a shared sighand_struct, so locking
650  * sighand_struct is always a proper superset of
651  * the locking of signal_struct.
652  */
653 struct signal_struct {
654 	atomic_t		sigcnt;
655 	atomic_t		live;
656 	int			nr_threads;
657 	struct list_head	thread_head;
658 
659 	wait_queue_head_t	wait_chldexit;	/* for wait4() */
660 
661 	/* current thread group signal load-balancing target: */
662 	struct task_struct	*curr_target;
663 
664 	/* shared signal handling: */
665 	struct sigpending	shared_pending;
666 
667 	/* thread group exit support */
668 	int			group_exit_code;
669 	/* overloaded:
670 	 * - notify group_exit_task when ->count is equal to notify_count
671 	 * - everyone except group_exit_task is stopped during signal delivery
672 	 *   of fatal signals, group_exit_task processes the signal.
673 	 */
674 	int			notify_count;
675 	struct task_struct	*group_exit_task;
676 
677 	/* thread group stop support, overloads group_exit_code too */
678 	int			group_stop_count;
679 	unsigned int		flags; /* see SIGNAL_* flags below */
680 
681 	/*
682 	 * PR_SET_CHILD_SUBREAPER marks a process, like a service
683 	 * manager, to re-parent orphan (double-forking) child processes
684 	 * to this process instead of 'init'. The service manager is
685 	 * able to receive SIGCHLD signals and is able to investigate
686 	 * the process until it calls wait(). All children of this
687 	 * process will inherit a flag if they should look for a
688 	 * child_subreaper process at exit.
689 	 */
690 	unsigned int		is_child_subreaper:1;
691 	unsigned int		has_child_subreaper:1;
692 
693 	/* POSIX.1b Interval Timers */
694 	int			posix_timer_id;
695 	struct list_head	posix_timers;
696 
697 	/* ITIMER_REAL timer for the process */
698 	struct hrtimer real_timer;
699 	struct pid *leader_pid;
700 	ktime_t it_real_incr;
701 
702 	/*
703 	 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
704 	 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
705 	 * values are defined to 0 and 1 respectively
706 	 */
707 	struct cpu_itimer it[2];
708 
709 	/*
710 	 * Thread group totals for process CPU timers.
711 	 * See thread_group_cputimer(), et al, for details.
712 	 */
713 	struct thread_group_cputimer cputimer;
714 
715 	/* Earliest-expiration cache. */
716 	struct task_cputime cputime_expires;
717 
718 	struct list_head cpu_timers[3];
719 
720 	struct pid *tty_old_pgrp;
721 
722 	/* boolean value for session group leader */
723 	int leader;
724 
725 	struct tty_struct *tty; /* NULL if no tty */
726 
727 #ifdef CONFIG_SCHED_AUTOGROUP
728 	struct autogroup *autogroup;
729 #endif
730 	/*
731 	 * Cumulative resource counters for dead threads in the group,
732 	 * and for reaped dead child processes forked by this group.
733 	 * Live threads maintain their own counters and add to these
734 	 * in __exit_signal, except for the group leader.
735 	 */
736 	seqlock_t stats_lock;
737 	cputime_t utime, stime, cutime, cstime;
738 	cputime_t gtime;
739 	cputime_t cgtime;
740 	struct prev_cputime prev_cputime;
741 	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
742 	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
743 	unsigned long inblock, oublock, cinblock, coublock;
744 	unsigned long maxrss, cmaxrss;
745 	struct task_io_accounting ioac;
746 
747 	/*
748 	 * Cumulative ns of schedule CPU time fo dead threads in the
749 	 * group, not including a zombie group leader, (This only differs
750 	 * from jiffies_to_ns(utime + stime) if sched_clock uses something
751 	 * other than jiffies.)
752 	 */
753 	unsigned long long sum_sched_runtime;
754 
755 	/*
756 	 * We don't bother to synchronize most readers of this at all,
757 	 * because there is no reader checking a limit that actually needs
758 	 * to get both rlim_cur and rlim_max atomically, and either one
759 	 * alone is a single word that can safely be read normally.
760 	 * getrlimit/setrlimit use task_lock(current->group_leader) to
761 	 * protect this instead of the siglock, because they really
762 	 * have no need to disable irqs.
763 	 */
764 	struct rlimit rlim[RLIM_NLIMITS];
765 
766 #ifdef CONFIG_BSD_PROCESS_ACCT
767 	struct pacct_struct pacct;	/* per-process accounting information */
768 #endif
769 #ifdef CONFIG_TASKSTATS
770 	struct taskstats *stats;
771 #endif
772 #ifdef CONFIG_AUDIT
773 	unsigned audit_tty;
774 	unsigned audit_tty_log_passwd;
775 	struct tty_audit_buf *tty_audit_buf;
776 #endif
777 
778 	oom_flags_t oom_flags;
779 	short oom_score_adj;		/* OOM kill score adjustment */
780 	short oom_score_adj_min;	/* OOM kill score adjustment min value.
781 					 * Only settable by CAP_SYS_RESOURCE. */
782 
783 	struct mutex cred_guard_mutex;	/* guard against foreign influences on
784 					 * credential calculations
785 					 * (notably. ptrace) */
786 };
787 
788 /*
789  * Bits in flags field of signal_struct.
790  */
791 #define SIGNAL_STOP_STOPPED	0x00000001 /* job control stop in effect */
792 #define SIGNAL_STOP_CONTINUED	0x00000002 /* SIGCONT since WCONTINUED reap */
793 #define SIGNAL_GROUP_EXIT	0x00000004 /* group exit in progress */
794 #define SIGNAL_GROUP_COREDUMP	0x00000008 /* coredump in progress */
795 /*
796  * Pending notifications to parent.
797  */
798 #define SIGNAL_CLD_STOPPED	0x00000010
799 #define SIGNAL_CLD_CONTINUED	0x00000020
800 #define SIGNAL_CLD_MASK		(SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
801 
802 #define SIGNAL_UNKILLABLE	0x00000040 /* for init: ignore fatal signals */
803 
804 /* If true, all threads except ->group_exit_task have pending SIGKILL */
805 static inline int signal_group_exit(const struct signal_struct *sig)
806 {
807 	return	(sig->flags & SIGNAL_GROUP_EXIT) ||
808 		(sig->group_exit_task != NULL);
809 }
810 
811 /*
812  * Some day this will be a full-fledged user tracking system..
813  */
814 struct user_struct {
815 	atomic_t __count;	/* reference count */
816 	atomic_t processes;	/* How many processes does this user have? */
817 	atomic_t sigpending;	/* How many pending signals does this user have? */
818 #ifdef CONFIG_INOTIFY_USER
819 	atomic_t inotify_watches; /* How many inotify watches does this user have? */
820 	atomic_t inotify_devs;	/* How many inotify devs does this user have opened? */
821 #endif
822 #ifdef CONFIG_FANOTIFY
823 	atomic_t fanotify_listeners;
824 #endif
825 #ifdef CONFIG_EPOLL
826 	atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
827 #endif
828 #ifdef CONFIG_POSIX_MQUEUE
829 	/* protected by mq_lock	*/
830 	unsigned long mq_bytes;	/* How many bytes can be allocated to mqueue? */
831 #endif
832 	unsigned long locked_shm; /* How many pages of mlocked shm ? */
833 
834 #ifdef CONFIG_KEYS
835 	struct key *uid_keyring;	/* UID specific keyring */
836 	struct key *session_keyring;	/* UID's default session keyring */
837 #endif
838 
839 	/* Hash table maintenance information */
840 	struct hlist_node uidhash_node;
841 	kuid_t uid;
842 
843 #if defined(CONFIG_PERF_EVENTS) || defined(CONFIG_BPF_SYSCALL)
844 	atomic_long_t locked_vm;
845 #endif
846 };
847 
848 extern int uids_sysfs_init(void);
849 
850 extern struct user_struct *find_user(kuid_t);
851 
852 extern struct user_struct root_user;
853 #define INIT_USER (&root_user)
854 
855 
856 struct backing_dev_info;
857 struct reclaim_state;
858 
859 #ifdef CONFIG_SCHED_INFO
860 struct sched_info {
861 	/* cumulative counters */
862 	unsigned long pcount;	      /* # of times run on this cpu */
863 	unsigned long long run_delay; /* time spent waiting on a runqueue */
864 
865 	/* timestamps */
866 	unsigned long long last_arrival,/* when we last ran on a cpu */
867 			   last_queued;	/* when we were last queued to run */
868 };
869 #endif /* CONFIG_SCHED_INFO */
870 
871 #ifdef CONFIG_TASK_DELAY_ACCT
872 struct task_delay_info {
873 	spinlock_t	lock;
874 	unsigned int	flags;	/* Private per-task flags */
875 
876 	/* For each stat XXX, add following, aligned appropriately
877 	 *
878 	 * struct timespec XXX_start, XXX_end;
879 	 * u64 XXX_delay;
880 	 * u32 XXX_count;
881 	 *
882 	 * Atomicity of updates to XXX_delay, XXX_count protected by
883 	 * single lock above (split into XXX_lock if contention is an issue).
884 	 */
885 
886 	/*
887 	 * XXX_count is incremented on every XXX operation, the delay
888 	 * associated with the operation is added to XXX_delay.
889 	 * XXX_delay contains the accumulated delay time in nanoseconds.
890 	 */
891 	u64 blkio_start;	/* Shared by blkio, swapin */
892 	u64 blkio_delay;	/* wait for sync block io completion */
893 	u64 swapin_delay;	/* wait for swapin block io completion */
894 	u32 blkio_count;	/* total count of the number of sync block */
895 				/* io operations performed */
896 	u32 swapin_count;	/* total count of the number of swapin block */
897 				/* io operations performed */
898 
899 	u64 freepages_start;
900 	u64 freepages_delay;	/* wait for memory reclaim */
901 	u32 freepages_count;	/* total count of memory reclaim */
902 };
903 #endif	/* CONFIG_TASK_DELAY_ACCT */
904 
905 static inline int sched_info_on(void)
906 {
907 #ifdef CONFIG_SCHEDSTATS
908 	return 1;
909 #elif defined(CONFIG_TASK_DELAY_ACCT)
910 	extern int delayacct_on;
911 	return delayacct_on;
912 #else
913 	return 0;
914 #endif
915 }
916 
917 enum cpu_idle_type {
918 	CPU_IDLE,
919 	CPU_NOT_IDLE,
920 	CPU_NEWLY_IDLE,
921 	CPU_MAX_IDLE_TYPES
922 };
923 
924 /*
925  * Increase resolution of cpu_capacity calculations
926  */
927 #define SCHED_CAPACITY_SHIFT	10
928 #define SCHED_CAPACITY_SCALE	(1L << SCHED_CAPACITY_SHIFT)
929 
930 /*
931  * Wake-queues are lists of tasks with a pending wakeup, whose
932  * callers have already marked the task as woken internally,
933  * and can thus carry on. A common use case is being able to
934  * do the wakeups once the corresponding user lock as been
935  * released.
936  *
937  * We hold reference to each task in the list across the wakeup,
938  * thus guaranteeing that the memory is still valid by the time
939  * the actual wakeups are performed in wake_up_q().
940  *
941  * One per task suffices, because there's never a need for a task to be
942  * in two wake queues simultaneously; it is forbidden to abandon a task
943  * in a wake queue (a call to wake_up_q() _must_ follow), so if a task is
944  * already in a wake queue, the wakeup will happen soon and the second
945  * waker can just skip it.
946  *
947  * The WAKE_Q macro declares and initializes the list head.
948  * wake_up_q() does NOT reinitialize the list; it's expected to be
949  * called near the end of a function, where the fact that the queue is
950  * not used again will be easy to see by inspection.
951  *
952  * Note that this can cause spurious wakeups. schedule() callers
953  * must ensure the call is done inside a loop, confirming that the
954  * wakeup condition has in fact occurred.
955  */
956 struct wake_q_node {
957 	struct wake_q_node *next;
958 };
959 
960 struct wake_q_head {
961 	struct wake_q_node *first;
962 	struct wake_q_node **lastp;
963 };
964 
965 #define WAKE_Q_TAIL ((struct wake_q_node *) 0x01)
966 
967 #define WAKE_Q(name)					\
968 	struct wake_q_head name = { WAKE_Q_TAIL, &name.first }
969 
970 extern void wake_q_add(struct wake_q_head *head,
971 		       struct task_struct *task);
972 extern void wake_up_q(struct wake_q_head *head);
973 
974 /*
975  * sched-domains (multiprocessor balancing) declarations:
976  */
977 #ifdef CONFIG_SMP
978 #define SD_LOAD_BALANCE		0x0001	/* Do load balancing on this domain. */
979 #define SD_BALANCE_NEWIDLE	0x0002	/* Balance when about to become idle */
980 #define SD_BALANCE_EXEC		0x0004	/* Balance on exec */
981 #define SD_BALANCE_FORK		0x0008	/* Balance on fork, clone */
982 #define SD_BALANCE_WAKE		0x0010  /* Balance on wakeup */
983 #define SD_WAKE_AFFINE		0x0020	/* Wake task to waking CPU */
984 #define SD_SHARE_CPUCAPACITY	0x0080	/* Domain members share cpu power */
985 #define SD_SHARE_POWERDOMAIN	0x0100	/* Domain members share power domain */
986 #define SD_SHARE_PKG_RESOURCES	0x0200	/* Domain members share cpu pkg resources */
987 #define SD_SERIALIZE		0x0400	/* Only a single load balancing instance */
988 #define SD_ASYM_PACKING		0x0800  /* Place busy groups earlier in the domain */
989 #define SD_PREFER_SIBLING	0x1000	/* Prefer to place tasks in a sibling domain */
990 #define SD_OVERLAP		0x2000	/* sched_domains of this level overlap */
991 #define SD_NUMA			0x4000	/* cross-node balancing */
992 
993 #ifdef CONFIG_SCHED_SMT
994 static inline int cpu_smt_flags(void)
995 {
996 	return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES;
997 }
998 #endif
999 
1000 #ifdef CONFIG_SCHED_MC
1001 static inline int cpu_core_flags(void)
1002 {
1003 	return SD_SHARE_PKG_RESOURCES;
1004 }
1005 #endif
1006 
1007 #ifdef CONFIG_NUMA
1008 static inline int cpu_numa_flags(void)
1009 {
1010 	return SD_NUMA;
1011 }
1012 #endif
1013 
1014 struct sched_domain_attr {
1015 	int relax_domain_level;
1016 };
1017 
1018 #define SD_ATTR_INIT	(struct sched_domain_attr) {	\
1019 	.relax_domain_level = -1,			\
1020 }
1021 
1022 extern int sched_domain_level_max;
1023 
1024 struct sched_group;
1025 
1026 struct sched_domain {
1027 	/* These fields must be setup */
1028 	struct sched_domain *parent;	/* top domain must be null terminated */
1029 	struct sched_domain *child;	/* bottom domain must be null terminated */
1030 	struct sched_group *groups;	/* the balancing groups of the domain */
1031 	unsigned long min_interval;	/* Minimum balance interval ms */
1032 	unsigned long max_interval;	/* Maximum balance interval ms */
1033 	unsigned int busy_factor;	/* less balancing by factor if busy */
1034 	unsigned int imbalance_pct;	/* No balance until over watermark */
1035 	unsigned int cache_nice_tries;	/* Leave cache hot tasks for # tries */
1036 	unsigned int busy_idx;
1037 	unsigned int idle_idx;
1038 	unsigned int newidle_idx;
1039 	unsigned int wake_idx;
1040 	unsigned int forkexec_idx;
1041 	unsigned int smt_gain;
1042 
1043 	int nohz_idle;			/* NOHZ IDLE status */
1044 	int flags;			/* See SD_* */
1045 	int level;
1046 
1047 	/* Runtime fields. */
1048 	unsigned long last_balance;	/* init to jiffies. units in jiffies */
1049 	unsigned int balance_interval;	/* initialise to 1. units in ms. */
1050 	unsigned int nr_balance_failed; /* initialise to 0 */
1051 
1052 	/* idle_balance() stats */
1053 	u64 max_newidle_lb_cost;
1054 	unsigned long next_decay_max_lb_cost;
1055 
1056 #ifdef CONFIG_SCHEDSTATS
1057 	/* load_balance() stats */
1058 	unsigned int lb_count[CPU_MAX_IDLE_TYPES];
1059 	unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
1060 	unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
1061 	unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
1062 	unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
1063 	unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
1064 	unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
1065 	unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
1066 
1067 	/* Active load balancing */
1068 	unsigned int alb_count;
1069 	unsigned int alb_failed;
1070 	unsigned int alb_pushed;
1071 
1072 	/* SD_BALANCE_EXEC stats */
1073 	unsigned int sbe_count;
1074 	unsigned int sbe_balanced;
1075 	unsigned int sbe_pushed;
1076 
1077 	/* SD_BALANCE_FORK stats */
1078 	unsigned int sbf_count;
1079 	unsigned int sbf_balanced;
1080 	unsigned int sbf_pushed;
1081 
1082 	/* try_to_wake_up() stats */
1083 	unsigned int ttwu_wake_remote;
1084 	unsigned int ttwu_move_affine;
1085 	unsigned int ttwu_move_balance;
1086 #endif
1087 #ifdef CONFIG_SCHED_DEBUG
1088 	char *name;
1089 #endif
1090 	union {
1091 		void *private;		/* used during construction */
1092 		struct rcu_head rcu;	/* used during destruction */
1093 	};
1094 
1095 	unsigned int span_weight;
1096 	/*
1097 	 * Span of all CPUs in this domain.
1098 	 *
1099 	 * NOTE: this field is variable length. (Allocated dynamically
1100 	 * by attaching extra space to the end of the structure,
1101 	 * depending on how many CPUs the kernel has booted up with)
1102 	 */
1103 	unsigned long span[0];
1104 };
1105 
1106 static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
1107 {
1108 	return to_cpumask(sd->span);
1109 }
1110 
1111 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1112 				    struct sched_domain_attr *dattr_new);
1113 
1114 /* Allocate an array of sched domains, for partition_sched_domains(). */
1115 cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
1116 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
1117 
1118 bool cpus_share_cache(int this_cpu, int that_cpu);
1119 
1120 typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
1121 typedef int (*sched_domain_flags_f)(void);
1122 
1123 #define SDTL_OVERLAP	0x01
1124 
1125 struct sd_data {
1126 	struct sched_domain **__percpu sd;
1127 	struct sched_group **__percpu sg;
1128 	struct sched_group_capacity **__percpu sgc;
1129 };
1130 
1131 struct sched_domain_topology_level {
1132 	sched_domain_mask_f mask;
1133 	sched_domain_flags_f sd_flags;
1134 	int		    flags;
1135 	int		    numa_level;
1136 	struct sd_data      data;
1137 #ifdef CONFIG_SCHED_DEBUG
1138 	char                *name;
1139 #endif
1140 };
1141 
1142 extern void set_sched_topology(struct sched_domain_topology_level *tl);
1143 extern void wake_up_if_idle(int cpu);
1144 
1145 #ifdef CONFIG_SCHED_DEBUG
1146 # define SD_INIT_NAME(type)		.name = #type
1147 #else
1148 # define SD_INIT_NAME(type)
1149 #endif
1150 
1151 #else /* CONFIG_SMP */
1152 
1153 struct sched_domain_attr;
1154 
1155 static inline void
1156 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1157 			struct sched_domain_attr *dattr_new)
1158 {
1159 }
1160 
1161 static inline bool cpus_share_cache(int this_cpu, int that_cpu)
1162 {
1163 	return true;
1164 }
1165 
1166 #endif	/* !CONFIG_SMP */
1167 
1168 
1169 struct io_context;			/* See blkdev.h */
1170 
1171 
1172 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1173 extern void prefetch_stack(struct task_struct *t);
1174 #else
1175 static inline void prefetch_stack(struct task_struct *t) { }
1176 #endif
1177 
1178 struct audit_context;		/* See audit.c */
1179 struct mempolicy;
1180 struct pipe_inode_info;
1181 struct uts_namespace;
1182 
1183 struct load_weight {
1184 	unsigned long weight;
1185 	u32 inv_weight;
1186 };
1187 
1188 /*
1189  * The load_avg/util_avg accumulates an infinite geometric series.
1190  * 1) load_avg factors frequency scaling into the amount of time that a
1191  * sched_entity is runnable on a rq into its weight. For cfs_rq, it is the
1192  * aggregated such weights of all runnable and blocked sched_entities.
1193  * 2) util_avg factors frequency and cpu scaling into the amount of time
1194  * that a sched_entity is running on a CPU, in the range [0..SCHED_LOAD_SCALE].
1195  * For cfs_rq, it is the aggregated such times of all runnable and
1196  * blocked sched_entities.
1197  * The 64 bit load_sum can:
1198  * 1) for cfs_rq, afford 4353082796 (=2^64/47742/88761) entities with
1199  * the highest weight (=88761) always runnable, we should not overflow
1200  * 2) for entity, support any load.weight always runnable
1201  */
1202 struct sched_avg {
1203 	u64 last_update_time, load_sum;
1204 	u32 util_sum, period_contrib;
1205 	unsigned long load_avg, util_avg;
1206 };
1207 
1208 #ifdef CONFIG_SCHEDSTATS
1209 struct sched_statistics {
1210 	u64			wait_start;
1211 	u64			wait_max;
1212 	u64			wait_count;
1213 	u64			wait_sum;
1214 	u64			iowait_count;
1215 	u64			iowait_sum;
1216 
1217 	u64			sleep_start;
1218 	u64			sleep_max;
1219 	s64			sum_sleep_runtime;
1220 
1221 	u64			block_start;
1222 	u64			block_max;
1223 	u64			exec_max;
1224 	u64			slice_max;
1225 
1226 	u64			nr_migrations_cold;
1227 	u64			nr_failed_migrations_affine;
1228 	u64			nr_failed_migrations_running;
1229 	u64			nr_failed_migrations_hot;
1230 	u64			nr_forced_migrations;
1231 
1232 	u64			nr_wakeups;
1233 	u64			nr_wakeups_sync;
1234 	u64			nr_wakeups_migrate;
1235 	u64			nr_wakeups_local;
1236 	u64			nr_wakeups_remote;
1237 	u64			nr_wakeups_affine;
1238 	u64			nr_wakeups_affine_attempts;
1239 	u64			nr_wakeups_passive;
1240 	u64			nr_wakeups_idle;
1241 };
1242 #endif
1243 
1244 struct sched_entity {
1245 	struct load_weight	load;		/* for load-balancing */
1246 	struct rb_node		run_node;
1247 	struct list_head	group_node;
1248 	unsigned int		on_rq;
1249 
1250 	u64			exec_start;
1251 	u64			sum_exec_runtime;
1252 	u64			vruntime;
1253 	u64			prev_sum_exec_runtime;
1254 
1255 	u64			nr_migrations;
1256 
1257 #ifdef CONFIG_SCHEDSTATS
1258 	struct sched_statistics statistics;
1259 #endif
1260 
1261 #ifdef CONFIG_FAIR_GROUP_SCHED
1262 	int			depth;
1263 	struct sched_entity	*parent;
1264 	/* rq on which this entity is (to be) queued: */
1265 	struct cfs_rq		*cfs_rq;
1266 	/* rq "owned" by this entity/group: */
1267 	struct cfs_rq		*my_q;
1268 #endif
1269 
1270 #ifdef CONFIG_SMP
1271 	/* Per entity load average tracking */
1272 	struct sched_avg	avg;
1273 #endif
1274 };
1275 
1276 struct sched_rt_entity {
1277 	struct list_head run_list;
1278 	unsigned long timeout;
1279 	unsigned long watchdog_stamp;
1280 	unsigned int time_slice;
1281 
1282 	struct sched_rt_entity *back;
1283 #ifdef CONFIG_RT_GROUP_SCHED
1284 	struct sched_rt_entity	*parent;
1285 	/* rq on which this entity is (to be) queued: */
1286 	struct rt_rq		*rt_rq;
1287 	/* rq "owned" by this entity/group: */
1288 	struct rt_rq		*my_q;
1289 #endif
1290 };
1291 
1292 struct sched_dl_entity {
1293 	struct rb_node	rb_node;
1294 
1295 	/*
1296 	 * Original scheduling parameters. Copied here from sched_attr
1297 	 * during sched_setattr(), they will remain the same until
1298 	 * the next sched_setattr().
1299 	 */
1300 	u64 dl_runtime;		/* maximum runtime for each instance	*/
1301 	u64 dl_deadline;	/* relative deadline of each instance	*/
1302 	u64 dl_period;		/* separation of two instances (period) */
1303 	u64 dl_bw;		/* dl_runtime / dl_deadline		*/
1304 
1305 	/*
1306 	 * Actual scheduling parameters. Initialized with the values above,
1307 	 * they are continously updated during task execution. Note that
1308 	 * the remaining runtime could be < 0 in case we are in overrun.
1309 	 */
1310 	s64 runtime;		/* remaining runtime for this instance	*/
1311 	u64 deadline;		/* absolute deadline for this instance	*/
1312 	unsigned int flags;	/* specifying the scheduler behaviour	*/
1313 
1314 	/*
1315 	 * Some bool flags:
1316 	 *
1317 	 * @dl_throttled tells if we exhausted the runtime. If so, the
1318 	 * task has to wait for a replenishment to be performed at the
1319 	 * next firing of dl_timer.
1320 	 *
1321 	 * @dl_new tells if a new instance arrived. If so we must
1322 	 * start executing it with full runtime and reset its absolute
1323 	 * deadline;
1324 	 *
1325 	 * @dl_boosted tells if we are boosted due to DI. If so we are
1326 	 * outside bandwidth enforcement mechanism (but only until we
1327 	 * exit the critical section);
1328 	 *
1329 	 * @dl_yielded tells if task gave up the cpu before consuming
1330 	 * all its available runtime during the last job.
1331 	 */
1332 	int dl_throttled, dl_new, dl_boosted, dl_yielded;
1333 
1334 	/*
1335 	 * Bandwidth enforcement timer. Each -deadline task has its
1336 	 * own bandwidth to be enforced, thus we need one timer per task.
1337 	 */
1338 	struct hrtimer dl_timer;
1339 };
1340 
1341 union rcu_special {
1342 	struct {
1343 		u8 blocked;
1344 		u8 need_qs;
1345 		u8 exp_need_qs;
1346 		u8 pad;	/* Otherwise the compiler can store garbage here. */
1347 	} b; /* Bits. */
1348 	u32 s; /* Set of bits. */
1349 };
1350 struct rcu_node;
1351 
1352 enum perf_event_task_context {
1353 	perf_invalid_context = -1,
1354 	perf_hw_context = 0,
1355 	perf_sw_context,
1356 	perf_nr_task_contexts,
1357 };
1358 
1359 /* Track pages that require TLB flushes */
1360 struct tlbflush_unmap_batch {
1361 	/*
1362 	 * Each bit set is a CPU that potentially has a TLB entry for one of
1363 	 * the PFNs being flushed. See set_tlb_ubc_flush_pending().
1364 	 */
1365 	struct cpumask cpumask;
1366 
1367 	/* True if any bit in cpumask is set */
1368 	bool flush_required;
1369 
1370 	/*
1371 	 * If true then the PTE was dirty when unmapped. The entry must be
1372 	 * flushed before IO is initiated or a stale TLB entry potentially
1373 	 * allows an update without redirtying the page.
1374 	 */
1375 	bool writable;
1376 };
1377 
1378 struct task_struct {
1379 	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
1380 	void *stack;
1381 	atomic_t usage;
1382 	unsigned int flags;	/* per process flags, defined below */
1383 	unsigned int ptrace;
1384 
1385 #ifdef CONFIG_SMP
1386 	struct llist_node wake_entry;
1387 	int on_cpu;
1388 	unsigned int wakee_flips;
1389 	unsigned long wakee_flip_decay_ts;
1390 	struct task_struct *last_wakee;
1391 
1392 	int wake_cpu;
1393 #endif
1394 	int on_rq;
1395 
1396 	int prio, static_prio, normal_prio;
1397 	unsigned int rt_priority;
1398 	const struct sched_class *sched_class;
1399 	struct sched_entity se;
1400 	struct sched_rt_entity rt;
1401 #ifdef CONFIG_CGROUP_SCHED
1402 	struct task_group *sched_task_group;
1403 #endif
1404 	struct sched_dl_entity dl;
1405 
1406 #ifdef CONFIG_PREEMPT_NOTIFIERS
1407 	/* list of struct preempt_notifier: */
1408 	struct hlist_head preempt_notifiers;
1409 #endif
1410 
1411 #ifdef CONFIG_BLK_DEV_IO_TRACE
1412 	unsigned int btrace_seq;
1413 #endif
1414 
1415 	unsigned int policy;
1416 	int nr_cpus_allowed;
1417 	cpumask_t cpus_allowed;
1418 
1419 #ifdef CONFIG_PREEMPT_RCU
1420 	int rcu_read_lock_nesting;
1421 	union rcu_special rcu_read_unlock_special;
1422 	struct list_head rcu_node_entry;
1423 	struct rcu_node *rcu_blocked_node;
1424 #endif /* #ifdef CONFIG_PREEMPT_RCU */
1425 #ifdef CONFIG_TASKS_RCU
1426 	unsigned long rcu_tasks_nvcsw;
1427 	bool rcu_tasks_holdout;
1428 	struct list_head rcu_tasks_holdout_list;
1429 	int rcu_tasks_idle_cpu;
1430 #endif /* #ifdef CONFIG_TASKS_RCU */
1431 
1432 #ifdef CONFIG_SCHED_INFO
1433 	struct sched_info sched_info;
1434 #endif
1435 
1436 	struct list_head tasks;
1437 #ifdef CONFIG_SMP
1438 	struct plist_node pushable_tasks;
1439 	struct rb_node pushable_dl_tasks;
1440 #endif
1441 
1442 	struct mm_struct *mm, *active_mm;
1443 	/* per-thread vma caching */
1444 	u32 vmacache_seqnum;
1445 	struct vm_area_struct *vmacache[VMACACHE_SIZE];
1446 #if defined(SPLIT_RSS_COUNTING)
1447 	struct task_rss_stat	rss_stat;
1448 #endif
1449 /* task state */
1450 	int exit_state;
1451 	int exit_code, exit_signal;
1452 	int pdeath_signal;  /*  The signal sent when the parent dies  */
1453 	unsigned long jobctl;	/* JOBCTL_*, siglock protected */
1454 
1455 	/* Used for emulating ABI behavior of previous Linux versions */
1456 	unsigned int personality;
1457 
1458 	unsigned in_execve:1;	/* Tell the LSMs that the process is doing an
1459 				 * execve */
1460 	unsigned in_iowait:1;
1461 
1462 	/* Revert to default priority/policy when forking */
1463 	unsigned sched_reset_on_fork:1;
1464 	unsigned sched_contributes_to_load:1;
1465 	unsigned sched_migrated:1;
1466 #ifdef CONFIG_MEMCG
1467 	unsigned memcg_may_oom:1;
1468 #endif
1469 #ifdef CONFIG_MEMCG_KMEM
1470 	unsigned memcg_kmem_skip_account:1;
1471 #endif
1472 #ifdef CONFIG_COMPAT_BRK
1473 	unsigned brk_randomized:1;
1474 #endif
1475 
1476 	unsigned long atomic_flags; /* Flags needing atomic access. */
1477 
1478 	struct restart_block restart_block;
1479 
1480 	pid_t pid;
1481 	pid_t tgid;
1482 
1483 #ifdef CONFIG_CC_STACKPROTECTOR
1484 	/* Canary value for the -fstack-protector gcc feature */
1485 	unsigned long stack_canary;
1486 #endif
1487 	/*
1488 	 * pointers to (original) parent process, youngest child, younger sibling,
1489 	 * older sibling, respectively.  (p->father can be replaced with
1490 	 * p->real_parent->pid)
1491 	 */
1492 	struct task_struct __rcu *real_parent; /* real parent process */
1493 	struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */
1494 	/*
1495 	 * children/sibling forms the list of my natural children
1496 	 */
1497 	struct list_head children;	/* list of my children */
1498 	struct list_head sibling;	/* linkage in my parent's children list */
1499 	struct task_struct *group_leader;	/* threadgroup leader */
1500 
1501 	/*
1502 	 * ptraced is the list of tasks this task is using ptrace on.
1503 	 * This includes both natural children and PTRACE_ATTACH targets.
1504 	 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1505 	 */
1506 	struct list_head ptraced;
1507 	struct list_head ptrace_entry;
1508 
1509 	/* PID/PID hash table linkage. */
1510 	struct pid_link pids[PIDTYPE_MAX];
1511 	struct list_head thread_group;
1512 	struct list_head thread_node;
1513 
1514 	struct completion *vfork_done;		/* for vfork() */
1515 	int __user *set_child_tid;		/* CLONE_CHILD_SETTID */
1516 	int __user *clear_child_tid;		/* CLONE_CHILD_CLEARTID */
1517 
1518 	cputime_t utime, stime, utimescaled, stimescaled;
1519 	cputime_t gtime;
1520 	struct prev_cputime prev_cputime;
1521 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1522 	seqlock_t vtime_seqlock;
1523 	unsigned long long vtime_snap;
1524 	enum {
1525 		VTIME_SLEEPING = 0,
1526 		VTIME_USER,
1527 		VTIME_SYS,
1528 	} vtime_snap_whence;
1529 #endif
1530 	unsigned long nvcsw, nivcsw; /* context switch counts */
1531 	u64 start_time;		/* monotonic time in nsec */
1532 	u64 real_start_time;	/* boot based time in nsec */
1533 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1534 	unsigned long min_flt, maj_flt;
1535 
1536 	struct task_cputime cputime_expires;
1537 	struct list_head cpu_timers[3];
1538 
1539 /* process credentials */
1540 	const struct cred __rcu *real_cred; /* objective and real subjective task
1541 					 * credentials (COW) */
1542 	const struct cred __rcu *cred;	/* effective (overridable) subjective task
1543 					 * credentials (COW) */
1544 	char comm[TASK_COMM_LEN]; /* executable name excluding path
1545 				     - access with [gs]et_task_comm (which lock
1546 				       it with task_lock())
1547 				     - initialized normally by setup_new_exec */
1548 /* file system info */
1549 	struct nameidata *nameidata;
1550 #ifdef CONFIG_SYSVIPC
1551 /* ipc stuff */
1552 	struct sysv_sem sysvsem;
1553 	struct sysv_shm sysvshm;
1554 #endif
1555 #ifdef CONFIG_DETECT_HUNG_TASK
1556 /* hung task detection */
1557 	unsigned long last_switch_count;
1558 #endif
1559 /* filesystem information */
1560 	struct fs_struct *fs;
1561 /* open file information */
1562 	struct files_struct *files;
1563 /* namespaces */
1564 	struct nsproxy *nsproxy;
1565 /* signal handlers */
1566 	struct signal_struct *signal;
1567 	struct sighand_struct *sighand;
1568 
1569 	sigset_t blocked, real_blocked;
1570 	sigset_t saved_sigmask;	/* restored if set_restore_sigmask() was used */
1571 	struct sigpending pending;
1572 
1573 	unsigned long sas_ss_sp;
1574 	size_t sas_ss_size;
1575 
1576 	struct callback_head *task_works;
1577 
1578 	struct audit_context *audit_context;
1579 #ifdef CONFIG_AUDITSYSCALL
1580 	kuid_t loginuid;
1581 	unsigned int sessionid;
1582 #endif
1583 	struct seccomp seccomp;
1584 
1585 /* Thread group tracking */
1586    	u32 parent_exec_id;
1587    	u32 self_exec_id;
1588 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1589  * mempolicy */
1590 	spinlock_t alloc_lock;
1591 
1592 	/* Protection of the PI data structures: */
1593 	raw_spinlock_t pi_lock;
1594 
1595 	struct wake_q_node wake_q;
1596 
1597 #ifdef CONFIG_RT_MUTEXES
1598 	/* PI waiters blocked on a rt_mutex held by this task */
1599 	struct rb_root pi_waiters;
1600 	struct rb_node *pi_waiters_leftmost;
1601 	/* Deadlock detection and priority inheritance handling */
1602 	struct rt_mutex_waiter *pi_blocked_on;
1603 #endif
1604 
1605 #ifdef CONFIG_DEBUG_MUTEXES
1606 	/* mutex deadlock detection */
1607 	struct mutex_waiter *blocked_on;
1608 #endif
1609 #ifdef CONFIG_TRACE_IRQFLAGS
1610 	unsigned int irq_events;
1611 	unsigned long hardirq_enable_ip;
1612 	unsigned long hardirq_disable_ip;
1613 	unsigned int hardirq_enable_event;
1614 	unsigned int hardirq_disable_event;
1615 	int hardirqs_enabled;
1616 	int hardirq_context;
1617 	unsigned long softirq_disable_ip;
1618 	unsigned long softirq_enable_ip;
1619 	unsigned int softirq_disable_event;
1620 	unsigned int softirq_enable_event;
1621 	int softirqs_enabled;
1622 	int softirq_context;
1623 #endif
1624 #ifdef CONFIG_LOCKDEP
1625 # define MAX_LOCK_DEPTH 48UL
1626 	u64 curr_chain_key;
1627 	int lockdep_depth;
1628 	unsigned int lockdep_recursion;
1629 	struct held_lock held_locks[MAX_LOCK_DEPTH];
1630 	gfp_t lockdep_reclaim_gfp;
1631 #endif
1632 
1633 /* journalling filesystem info */
1634 	void *journal_info;
1635 
1636 /* stacked block device info */
1637 	struct bio_list *bio_list;
1638 
1639 #ifdef CONFIG_BLOCK
1640 /* stack plugging */
1641 	struct blk_plug *plug;
1642 #endif
1643 
1644 /* VM state */
1645 	struct reclaim_state *reclaim_state;
1646 
1647 	struct backing_dev_info *backing_dev_info;
1648 
1649 	struct io_context *io_context;
1650 
1651 	unsigned long ptrace_message;
1652 	siginfo_t *last_siginfo; /* For ptrace use.  */
1653 	struct task_io_accounting ioac;
1654 #if defined(CONFIG_TASK_XACCT)
1655 	u64 acct_rss_mem1;	/* accumulated rss usage */
1656 	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
1657 	cputime_t acct_timexpd;	/* stime + utime since last update */
1658 #endif
1659 #ifdef CONFIG_CPUSETS
1660 	nodemask_t mems_allowed;	/* Protected by alloc_lock */
1661 	seqcount_t mems_allowed_seq;	/* Seqence no to catch updates */
1662 	int cpuset_mem_spread_rotor;
1663 	int cpuset_slab_spread_rotor;
1664 #endif
1665 #ifdef CONFIG_CGROUPS
1666 	/* Control Group info protected by css_set_lock */
1667 	struct css_set __rcu *cgroups;
1668 	/* cg_list protected by css_set_lock and tsk->alloc_lock */
1669 	struct list_head cg_list;
1670 #endif
1671 #ifdef CONFIG_FUTEX
1672 	struct robust_list_head __user *robust_list;
1673 #ifdef CONFIG_COMPAT
1674 	struct compat_robust_list_head __user *compat_robust_list;
1675 #endif
1676 	struct list_head pi_state_list;
1677 	struct futex_pi_state *pi_state_cache;
1678 #endif
1679 #ifdef CONFIG_PERF_EVENTS
1680 	struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1681 	struct mutex perf_event_mutex;
1682 	struct list_head perf_event_list;
1683 #endif
1684 #ifdef CONFIG_DEBUG_PREEMPT
1685 	unsigned long preempt_disable_ip;
1686 #endif
1687 #ifdef CONFIG_NUMA
1688 	struct mempolicy *mempolicy;	/* Protected by alloc_lock */
1689 	short il_next;
1690 	short pref_node_fork;
1691 #endif
1692 #ifdef CONFIG_NUMA_BALANCING
1693 	int numa_scan_seq;
1694 	unsigned int numa_scan_period;
1695 	unsigned int numa_scan_period_max;
1696 	int numa_preferred_nid;
1697 	unsigned long numa_migrate_retry;
1698 	u64 node_stamp;			/* migration stamp  */
1699 	u64 last_task_numa_placement;
1700 	u64 last_sum_exec_runtime;
1701 	struct callback_head numa_work;
1702 
1703 	struct list_head numa_entry;
1704 	struct numa_group *numa_group;
1705 
1706 	/*
1707 	 * numa_faults is an array split into four regions:
1708 	 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1709 	 * in this precise order.
1710 	 *
1711 	 * faults_memory: Exponential decaying average of faults on a per-node
1712 	 * basis. Scheduling placement decisions are made based on these
1713 	 * counts. The values remain static for the duration of a PTE scan.
1714 	 * faults_cpu: Track the nodes the process was running on when a NUMA
1715 	 * hinting fault was incurred.
1716 	 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1717 	 * during the current scan window. When the scan completes, the counts
1718 	 * in faults_memory and faults_cpu decay and these values are copied.
1719 	 */
1720 	unsigned long *numa_faults;
1721 	unsigned long total_numa_faults;
1722 
1723 	/*
1724 	 * numa_faults_locality tracks if faults recorded during the last
1725 	 * scan window were remote/local or failed to migrate. The task scan
1726 	 * period is adapted based on the locality of the faults with different
1727 	 * weights depending on whether they were shared or private faults
1728 	 */
1729 	unsigned long numa_faults_locality[3];
1730 
1731 	unsigned long numa_pages_migrated;
1732 #endif /* CONFIG_NUMA_BALANCING */
1733 
1734 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
1735 	struct tlbflush_unmap_batch tlb_ubc;
1736 #endif
1737 
1738 	struct rcu_head rcu;
1739 
1740 	/*
1741 	 * cache last used pipe for splice
1742 	 */
1743 	struct pipe_inode_info *splice_pipe;
1744 
1745 	struct page_frag task_frag;
1746 
1747 #ifdef	CONFIG_TASK_DELAY_ACCT
1748 	struct task_delay_info *delays;
1749 #endif
1750 #ifdef CONFIG_FAULT_INJECTION
1751 	int make_it_fail;
1752 #endif
1753 	/*
1754 	 * when (nr_dirtied >= nr_dirtied_pause), it's time to call
1755 	 * balance_dirty_pages() for some dirty throttling pause
1756 	 */
1757 	int nr_dirtied;
1758 	int nr_dirtied_pause;
1759 	unsigned long dirty_paused_when; /* start of a write-and-pause period */
1760 
1761 #ifdef CONFIG_LATENCYTOP
1762 	int latency_record_count;
1763 	struct latency_record latency_record[LT_SAVECOUNT];
1764 #endif
1765 	/*
1766 	 * time slack values; these are used to round up poll() and
1767 	 * select() etc timeout values. These are in nanoseconds.
1768 	 */
1769 	unsigned long timer_slack_ns;
1770 	unsigned long default_timer_slack_ns;
1771 
1772 #ifdef CONFIG_KASAN
1773 	unsigned int kasan_depth;
1774 #endif
1775 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1776 	/* Index of current stored address in ret_stack */
1777 	int curr_ret_stack;
1778 	/* Stack of return addresses for return function tracing */
1779 	struct ftrace_ret_stack	*ret_stack;
1780 	/* time stamp for last schedule */
1781 	unsigned long long ftrace_timestamp;
1782 	/*
1783 	 * Number of functions that haven't been traced
1784 	 * because of depth overrun.
1785 	 */
1786 	atomic_t trace_overrun;
1787 	/* Pause for the tracing */
1788 	atomic_t tracing_graph_pause;
1789 #endif
1790 #ifdef CONFIG_TRACING
1791 	/* state flags for use by tracers */
1792 	unsigned long trace;
1793 	/* bitmask and counter of trace recursion */
1794 	unsigned long trace_recursion;
1795 #endif /* CONFIG_TRACING */
1796 #ifdef CONFIG_MEMCG
1797 	struct mem_cgroup *memcg_in_oom;
1798 	gfp_t memcg_oom_gfp_mask;
1799 	int memcg_oom_order;
1800 
1801 	/* number of pages to reclaim on returning to userland */
1802 	unsigned int memcg_nr_pages_over_high;
1803 #endif
1804 #ifdef CONFIG_UPROBES
1805 	struct uprobe_task *utask;
1806 #endif
1807 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1808 	unsigned int	sequential_io;
1809 	unsigned int	sequential_io_avg;
1810 #endif
1811 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1812 	unsigned long	task_state_change;
1813 #endif
1814 	int pagefault_disabled;
1815 /* CPU-specific state of this task */
1816 	struct thread_struct thread;
1817 /*
1818  * WARNING: on x86, 'thread_struct' contains a variable-sized
1819  * structure.  It *MUST* be at the end of 'task_struct'.
1820  *
1821  * Do not put anything below here!
1822  */
1823 };
1824 
1825 #ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT
1826 extern int arch_task_struct_size __read_mostly;
1827 #else
1828 # define arch_task_struct_size (sizeof(struct task_struct))
1829 #endif
1830 
1831 /* Future-safe accessor for struct task_struct's cpus_allowed. */
1832 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1833 
1834 #define TNF_MIGRATED	0x01
1835 #define TNF_NO_GROUP	0x02
1836 #define TNF_SHARED	0x04
1837 #define TNF_FAULT_LOCAL	0x08
1838 #define TNF_MIGRATE_FAIL 0x10
1839 
1840 #ifdef CONFIG_NUMA_BALANCING
1841 extern void task_numa_fault(int last_node, int node, int pages, int flags);
1842 extern pid_t task_numa_group_id(struct task_struct *p);
1843 extern void set_numabalancing_state(bool enabled);
1844 extern void task_numa_free(struct task_struct *p);
1845 extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page,
1846 					int src_nid, int dst_cpu);
1847 #else
1848 static inline void task_numa_fault(int last_node, int node, int pages,
1849 				   int flags)
1850 {
1851 }
1852 static inline pid_t task_numa_group_id(struct task_struct *p)
1853 {
1854 	return 0;
1855 }
1856 static inline void set_numabalancing_state(bool enabled)
1857 {
1858 }
1859 static inline void task_numa_free(struct task_struct *p)
1860 {
1861 }
1862 static inline bool should_numa_migrate_memory(struct task_struct *p,
1863 				struct page *page, int src_nid, int dst_cpu)
1864 {
1865 	return true;
1866 }
1867 #endif
1868 
1869 static inline struct pid *task_pid(struct task_struct *task)
1870 {
1871 	return task->pids[PIDTYPE_PID].pid;
1872 }
1873 
1874 static inline struct pid *task_tgid(struct task_struct *task)
1875 {
1876 	return task->group_leader->pids[PIDTYPE_PID].pid;
1877 }
1878 
1879 /*
1880  * Without tasklist or rcu lock it is not safe to dereference
1881  * the result of task_pgrp/task_session even if task == current,
1882  * we can race with another thread doing sys_setsid/sys_setpgid.
1883  */
1884 static inline struct pid *task_pgrp(struct task_struct *task)
1885 {
1886 	return task->group_leader->pids[PIDTYPE_PGID].pid;
1887 }
1888 
1889 static inline struct pid *task_session(struct task_struct *task)
1890 {
1891 	return task->group_leader->pids[PIDTYPE_SID].pid;
1892 }
1893 
1894 struct pid_namespace;
1895 
1896 /*
1897  * the helpers to get the task's different pids as they are seen
1898  * from various namespaces
1899  *
1900  * task_xid_nr()     : global id, i.e. the id seen from the init namespace;
1901  * task_xid_vnr()    : virtual id, i.e. the id seen from the pid namespace of
1902  *                     current.
1903  * task_xid_nr_ns()  : id seen from the ns specified;
1904  *
1905  * set_task_vxid()   : assigns a virtual id to a task;
1906  *
1907  * see also pid_nr() etc in include/linux/pid.h
1908  */
1909 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1910 			struct pid_namespace *ns);
1911 
1912 static inline pid_t task_pid_nr(struct task_struct *tsk)
1913 {
1914 	return tsk->pid;
1915 }
1916 
1917 static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1918 					struct pid_namespace *ns)
1919 {
1920 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1921 }
1922 
1923 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1924 {
1925 	return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1926 }
1927 
1928 
1929 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1930 {
1931 	return tsk->tgid;
1932 }
1933 
1934 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1935 
1936 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1937 {
1938 	return pid_vnr(task_tgid(tsk));
1939 }
1940 
1941 
1942 static inline int pid_alive(const struct task_struct *p);
1943 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1944 {
1945 	pid_t pid = 0;
1946 
1947 	rcu_read_lock();
1948 	if (pid_alive(tsk))
1949 		pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1950 	rcu_read_unlock();
1951 
1952 	return pid;
1953 }
1954 
1955 static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1956 {
1957 	return task_ppid_nr_ns(tsk, &init_pid_ns);
1958 }
1959 
1960 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1961 					struct pid_namespace *ns)
1962 {
1963 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1964 }
1965 
1966 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1967 {
1968 	return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1969 }
1970 
1971 
1972 static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1973 					struct pid_namespace *ns)
1974 {
1975 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1976 }
1977 
1978 static inline pid_t task_session_vnr(struct task_struct *tsk)
1979 {
1980 	return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1981 }
1982 
1983 /* obsolete, do not use */
1984 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1985 {
1986 	return task_pgrp_nr_ns(tsk, &init_pid_ns);
1987 }
1988 
1989 /**
1990  * pid_alive - check that a task structure is not stale
1991  * @p: Task structure to be checked.
1992  *
1993  * Test if a process is not yet dead (at most zombie state)
1994  * If pid_alive fails, then pointers within the task structure
1995  * can be stale and must not be dereferenced.
1996  *
1997  * Return: 1 if the process is alive. 0 otherwise.
1998  */
1999 static inline int pid_alive(const struct task_struct *p)
2000 {
2001 	return p->pids[PIDTYPE_PID].pid != NULL;
2002 }
2003 
2004 /**
2005  * is_global_init - check if a task structure is init
2006  * @tsk: Task structure to be checked.
2007  *
2008  * Check if a task structure is the first user space task the kernel created.
2009  *
2010  * Return: 1 if the task structure is init. 0 otherwise.
2011  */
2012 static inline int is_global_init(struct task_struct *tsk)
2013 {
2014 	return tsk->pid == 1;
2015 }
2016 
2017 extern struct pid *cad_pid;
2018 
2019 extern void free_task(struct task_struct *tsk);
2020 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
2021 
2022 extern void __put_task_struct(struct task_struct *t);
2023 
2024 static inline void put_task_struct(struct task_struct *t)
2025 {
2026 	if (atomic_dec_and_test(&t->usage))
2027 		__put_task_struct(t);
2028 }
2029 
2030 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
2031 extern void task_cputime(struct task_struct *t,
2032 			 cputime_t *utime, cputime_t *stime);
2033 extern void task_cputime_scaled(struct task_struct *t,
2034 				cputime_t *utimescaled, cputime_t *stimescaled);
2035 extern cputime_t task_gtime(struct task_struct *t);
2036 #else
2037 static inline void task_cputime(struct task_struct *t,
2038 				cputime_t *utime, cputime_t *stime)
2039 {
2040 	if (utime)
2041 		*utime = t->utime;
2042 	if (stime)
2043 		*stime = t->stime;
2044 }
2045 
2046 static inline void task_cputime_scaled(struct task_struct *t,
2047 				       cputime_t *utimescaled,
2048 				       cputime_t *stimescaled)
2049 {
2050 	if (utimescaled)
2051 		*utimescaled = t->utimescaled;
2052 	if (stimescaled)
2053 		*stimescaled = t->stimescaled;
2054 }
2055 
2056 static inline cputime_t task_gtime(struct task_struct *t)
2057 {
2058 	return t->gtime;
2059 }
2060 #endif
2061 extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
2062 extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
2063 
2064 /*
2065  * Per process flags
2066  */
2067 #define PF_EXITING	0x00000004	/* getting shut down */
2068 #define PF_EXITPIDONE	0x00000008	/* pi exit done on shut down */
2069 #define PF_VCPU		0x00000010	/* I'm a virtual CPU */
2070 #define PF_WQ_WORKER	0x00000020	/* I'm a workqueue worker */
2071 #define PF_FORKNOEXEC	0x00000040	/* forked but didn't exec */
2072 #define PF_MCE_PROCESS  0x00000080      /* process policy on mce errors */
2073 #define PF_SUPERPRIV	0x00000100	/* used super-user privileges */
2074 #define PF_DUMPCORE	0x00000200	/* dumped core */
2075 #define PF_SIGNALED	0x00000400	/* killed by a signal */
2076 #define PF_MEMALLOC	0x00000800	/* Allocating memory */
2077 #define PF_NPROC_EXCEEDED 0x00001000	/* set_user noticed that RLIMIT_NPROC was exceeded */
2078 #define PF_USED_MATH	0x00002000	/* if unset the fpu must be initialized before use */
2079 #define PF_USED_ASYNC	0x00004000	/* used async_schedule*(), used by module init */
2080 #define PF_NOFREEZE	0x00008000	/* this thread should not be frozen */
2081 #define PF_FROZEN	0x00010000	/* frozen for system suspend */
2082 #define PF_FSTRANS	0x00020000	/* inside a filesystem transaction */
2083 #define PF_KSWAPD	0x00040000	/* I am kswapd */
2084 #define PF_MEMALLOC_NOIO 0x00080000	/* Allocating memory without IO involved */
2085 #define PF_LESS_THROTTLE 0x00100000	/* Throttle me less: I clean memory */
2086 #define PF_KTHREAD	0x00200000	/* I am a kernel thread */
2087 #define PF_RANDOMIZE	0x00400000	/* randomize virtual address space */
2088 #define PF_SWAPWRITE	0x00800000	/* Allowed to write to swap */
2089 #define PF_NO_SETAFFINITY 0x04000000	/* Userland is not allowed to meddle with cpus_allowed */
2090 #define PF_MCE_EARLY    0x08000000      /* Early kill for mce process policy */
2091 #define PF_MUTEX_TESTER	0x20000000	/* Thread belongs to the rt mutex tester */
2092 #define PF_FREEZER_SKIP	0x40000000	/* Freezer should not count it as freezable */
2093 #define PF_SUSPEND_TASK 0x80000000      /* this thread called freeze_processes and should not be frozen */
2094 
2095 /*
2096  * Only the _current_ task can read/write to tsk->flags, but other
2097  * tasks can access tsk->flags in readonly mode for example
2098  * with tsk_used_math (like during threaded core dumping).
2099  * There is however an exception to this rule during ptrace
2100  * or during fork: the ptracer task is allowed to write to the
2101  * child->flags of its traced child (same goes for fork, the parent
2102  * can write to the child->flags), because we're guaranteed the
2103  * child is not running and in turn not changing child->flags
2104  * at the same time the parent does it.
2105  */
2106 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
2107 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
2108 #define clear_used_math() clear_stopped_child_used_math(current)
2109 #define set_used_math() set_stopped_child_used_math(current)
2110 #define conditional_stopped_child_used_math(condition, child) \
2111 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
2112 #define conditional_used_math(condition) \
2113 	conditional_stopped_child_used_math(condition, current)
2114 #define copy_to_stopped_child_used_math(child) \
2115 	do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
2116 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
2117 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
2118 #define used_math() tsk_used_math(current)
2119 
2120 /* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags
2121  * __GFP_FS is also cleared as it implies __GFP_IO.
2122  */
2123 static inline gfp_t memalloc_noio_flags(gfp_t flags)
2124 {
2125 	if (unlikely(current->flags & PF_MEMALLOC_NOIO))
2126 		flags &= ~(__GFP_IO | __GFP_FS);
2127 	return flags;
2128 }
2129 
2130 static inline unsigned int memalloc_noio_save(void)
2131 {
2132 	unsigned int flags = current->flags & PF_MEMALLOC_NOIO;
2133 	current->flags |= PF_MEMALLOC_NOIO;
2134 	return flags;
2135 }
2136 
2137 static inline void memalloc_noio_restore(unsigned int flags)
2138 {
2139 	current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags;
2140 }
2141 
2142 /* Per-process atomic flags. */
2143 #define PFA_NO_NEW_PRIVS 0	/* May not gain new privileges. */
2144 #define PFA_SPREAD_PAGE  1      /* Spread page cache over cpuset */
2145 #define PFA_SPREAD_SLAB  2      /* Spread some slab caches over cpuset */
2146 
2147 
2148 #define TASK_PFA_TEST(name, func)					\
2149 	static inline bool task_##func(struct task_struct *p)		\
2150 	{ return test_bit(PFA_##name, &p->atomic_flags); }
2151 #define TASK_PFA_SET(name, func)					\
2152 	static inline void task_set_##func(struct task_struct *p)	\
2153 	{ set_bit(PFA_##name, &p->atomic_flags); }
2154 #define TASK_PFA_CLEAR(name, func)					\
2155 	static inline void task_clear_##func(struct task_struct *p)	\
2156 	{ clear_bit(PFA_##name, &p->atomic_flags); }
2157 
2158 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
2159 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
2160 
2161 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
2162 TASK_PFA_SET(SPREAD_PAGE, spread_page)
2163 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
2164 
2165 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
2166 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
2167 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
2168 
2169 /*
2170  * task->jobctl flags
2171  */
2172 #define JOBCTL_STOP_SIGMASK	0xffff	/* signr of the last group stop */
2173 
2174 #define JOBCTL_STOP_DEQUEUED_BIT 16	/* stop signal dequeued */
2175 #define JOBCTL_STOP_PENDING_BIT	17	/* task should stop for group stop */
2176 #define JOBCTL_STOP_CONSUME_BIT	18	/* consume group stop count */
2177 #define JOBCTL_TRAP_STOP_BIT	19	/* trap for STOP */
2178 #define JOBCTL_TRAP_NOTIFY_BIT	20	/* trap for NOTIFY */
2179 #define JOBCTL_TRAPPING_BIT	21	/* switching to TRACED */
2180 #define JOBCTL_LISTENING_BIT	22	/* ptracer is listening for events */
2181 
2182 #define JOBCTL_STOP_DEQUEUED	(1UL << JOBCTL_STOP_DEQUEUED_BIT)
2183 #define JOBCTL_STOP_PENDING	(1UL << JOBCTL_STOP_PENDING_BIT)
2184 #define JOBCTL_STOP_CONSUME	(1UL << JOBCTL_STOP_CONSUME_BIT)
2185 #define JOBCTL_TRAP_STOP	(1UL << JOBCTL_TRAP_STOP_BIT)
2186 #define JOBCTL_TRAP_NOTIFY	(1UL << JOBCTL_TRAP_NOTIFY_BIT)
2187 #define JOBCTL_TRAPPING		(1UL << JOBCTL_TRAPPING_BIT)
2188 #define JOBCTL_LISTENING	(1UL << JOBCTL_LISTENING_BIT)
2189 
2190 #define JOBCTL_TRAP_MASK	(JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY)
2191 #define JOBCTL_PENDING_MASK	(JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK)
2192 
2193 extern bool task_set_jobctl_pending(struct task_struct *task,
2194 				    unsigned long mask);
2195 extern void task_clear_jobctl_trapping(struct task_struct *task);
2196 extern void task_clear_jobctl_pending(struct task_struct *task,
2197 				      unsigned long mask);
2198 
2199 static inline void rcu_copy_process(struct task_struct *p)
2200 {
2201 #ifdef CONFIG_PREEMPT_RCU
2202 	p->rcu_read_lock_nesting = 0;
2203 	p->rcu_read_unlock_special.s = 0;
2204 	p->rcu_blocked_node = NULL;
2205 	INIT_LIST_HEAD(&p->rcu_node_entry);
2206 #endif /* #ifdef CONFIG_PREEMPT_RCU */
2207 #ifdef CONFIG_TASKS_RCU
2208 	p->rcu_tasks_holdout = false;
2209 	INIT_LIST_HEAD(&p->rcu_tasks_holdout_list);
2210 	p->rcu_tasks_idle_cpu = -1;
2211 #endif /* #ifdef CONFIG_TASKS_RCU */
2212 }
2213 
2214 static inline void tsk_restore_flags(struct task_struct *task,
2215 				unsigned long orig_flags, unsigned long flags)
2216 {
2217 	task->flags &= ~flags;
2218 	task->flags |= orig_flags & flags;
2219 }
2220 
2221 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur,
2222 				     const struct cpumask *trial);
2223 extern int task_can_attach(struct task_struct *p,
2224 			   const struct cpumask *cs_cpus_allowed);
2225 #ifdef CONFIG_SMP
2226 extern void do_set_cpus_allowed(struct task_struct *p,
2227 			       const struct cpumask *new_mask);
2228 
2229 extern int set_cpus_allowed_ptr(struct task_struct *p,
2230 				const struct cpumask *new_mask);
2231 #else
2232 static inline void do_set_cpus_allowed(struct task_struct *p,
2233 				      const struct cpumask *new_mask)
2234 {
2235 }
2236 static inline int set_cpus_allowed_ptr(struct task_struct *p,
2237 				       const struct cpumask *new_mask)
2238 {
2239 	if (!cpumask_test_cpu(0, new_mask))
2240 		return -EINVAL;
2241 	return 0;
2242 }
2243 #endif
2244 
2245 #ifdef CONFIG_NO_HZ_COMMON
2246 void calc_load_enter_idle(void);
2247 void calc_load_exit_idle(void);
2248 #else
2249 static inline void calc_load_enter_idle(void) { }
2250 static inline void calc_load_exit_idle(void) { }
2251 #endif /* CONFIG_NO_HZ_COMMON */
2252 
2253 /*
2254  * Do not use outside of architecture code which knows its limitations.
2255  *
2256  * sched_clock() has no promise of monotonicity or bounded drift between
2257  * CPUs, use (which you should not) requires disabling IRQs.
2258  *
2259  * Please use one of the three interfaces below.
2260  */
2261 extern unsigned long long notrace sched_clock(void);
2262 /*
2263  * See the comment in kernel/sched/clock.c
2264  */
2265 extern u64 cpu_clock(int cpu);
2266 extern u64 local_clock(void);
2267 extern u64 running_clock(void);
2268 extern u64 sched_clock_cpu(int cpu);
2269 
2270 
2271 extern void sched_clock_init(void);
2272 
2273 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
2274 static inline void sched_clock_tick(void)
2275 {
2276 }
2277 
2278 static inline void sched_clock_idle_sleep_event(void)
2279 {
2280 }
2281 
2282 static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
2283 {
2284 }
2285 #else
2286 /*
2287  * Architectures can set this to 1 if they have specified
2288  * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
2289  * but then during bootup it turns out that sched_clock()
2290  * is reliable after all:
2291  */
2292 extern int sched_clock_stable(void);
2293 extern void set_sched_clock_stable(void);
2294 extern void clear_sched_clock_stable(void);
2295 
2296 extern void sched_clock_tick(void);
2297 extern void sched_clock_idle_sleep_event(void);
2298 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2299 #endif
2300 
2301 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2302 /*
2303  * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
2304  * The reason for this explicit opt-in is not to have perf penalty with
2305  * slow sched_clocks.
2306  */
2307 extern void enable_sched_clock_irqtime(void);
2308 extern void disable_sched_clock_irqtime(void);
2309 #else
2310 static inline void enable_sched_clock_irqtime(void) {}
2311 static inline void disable_sched_clock_irqtime(void) {}
2312 #endif
2313 
2314 extern unsigned long long
2315 task_sched_runtime(struct task_struct *task);
2316 
2317 /* sched_exec is called by processes performing an exec */
2318 #ifdef CONFIG_SMP
2319 extern void sched_exec(void);
2320 #else
2321 #define sched_exec()   {}
2322 #endif
2323 
2324 extern void sched_clock_idle_sleep_event(void);
2325 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2326 
2327 #ifdef CONFIG_HOTPLUG_CPU
2328 extern void idle_task_exit(void);
2329 #else
2330 static inline void idle_task_exit(void) {}
2331 #endif
2332 
2333 #if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
2334 extern void wake_up_nohz_cpu(int cpu);
2335 #else
2336 static inline void wake_up_nohz_cpu(int cpu) { }
2337 #endif
2338 
2339 #ifdef CONFIG_NO_HZ_FULL
2340 extern bool sched_can_stop_tick(void);
2341 extern u64 scheduler_tick_max_deferment(void);
2342 #else
2343 static inline bool sched_can_stop_tick(void) { return false; }
2344 #endif
2345 
2346 #ifdef CONFIG_SCHED_AUTOGROUP
2347 extern void sched_autogroup_create_attach(struct task_struct *p);
2348 extern void sched_autogroup_detach(struct task_struct *p);
2349 extern void sched_autogroup_fork(struct signal_struct *sig);
2350 extern void sched_autogroup_exit(struct signal_struct *sig);
2351 #ifdef CONFIG_PROC_FS
2352 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
2353 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice);
2354 #endif
2355 #else
2356 static inline void sched_autogroup_create_attach(struct task_struct *p) { }
2357 static inline void sched_autogroup_detach(struct task_struct *p) { }
2358 static inline void sched_autogroup_fork(struct signal_struct *sig) { }
2359 static inline void sched_autogroup_exit(struct signal_struct *sig) { }
2360 #endif
2361 
2362 extern int yield_to(struct task_struct *p, bool preempt);
2363 extern void set_user_nice(struct task_struct *p, long nice);
2364 extern int task_prio(const struct task_struct *p);
2365 /**
2366  * task_nice - return the nice value of a given task.
2367  * @p: the task in question.
2368  *
2369  * Return: The nice value [ -20 ... 0 ... 19 ].
2370  */
2371 static inline int task_nice(const struct task_struct *p)
2372 {
2373 	return PRIO_TO_NICE((p)->static_prio);
2374 }
2375 extern int can_nice(const struct task_struct *p, const int nice);
2376 extern int task_curr(const struct task_struct *p);
2377 extern int idle_cpu(int cpu);
2378 extern int sched_setscheduler(struct task_struct *, int,
2379 			      const struct sched_param *);
2380 extern int sched_setscheduler_nocheck(struct task_struct *, int,
2381 				      const struct sched_param *);
2382 extern int sched_setattr(struct task_struct *,
2383 			 const struct sched_attr *);
2384 extern struct task_struct *idle_task(int cpu);
2385 /**
2386  * is_idle_task - is the specified task an idle task?
2387  * @p: the task in question.
2388  *
2389  * Return: 1 if @p is an idle task. 0 otherwise.
2390  */
2391 static inline bool is_idle_task(const struct task_struct *p)
2392 {
2393 	return p->pid == 0;
2394 }
2395 extern struct task_struct *curr_task(int cpu);
2396 extern void set_curr_task(int cpu, struct task_struct *p);
2397 
2398 void yield(void);
2399 
2400 union thread_union {
2401 	struct thread_info thread_info;
2402 	unsigned long stack[THREAD_SIZE/sizeof(long)];
2403 };
2404 
2405 #ifndef __HAVE_ARCH_KSTACK_END
2406 static inline int kstack_end(void *addr)
2407 {
2408 	/* Reliable end of stack detection:
2409 	 * Some APM bios versions misalign the stack
2410 	 */
2411 	return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
2412 }
2413 #endif
2414 
2415 extern union thread_union init_thread_union;
2416 extern struct task_struct init_task;
2417 
2418 extern struct   mm_struct init_mm;
2419 
2420 extern struct pid_namespace init_pid_ns;
2421 
2422 /*
2423  * find a task by one of its numerical ids
2424  *
2425  * find_task_by_pid_ns():
2426  *      finds a task by its pid in the specified namespace
2427  * find_task_by_vpid():
2428  *      finds a task by its virtual pid
2429  *
2430  * see also find_vpid() etc in include/linux/pid.h
2431  */
2432 
2433 extern struct task_struct *find_task_by_vpid(pid_t nr);
2434 extern struct task_struct *find_task_by_pid_ns(pid_t nr,
2435 		struct pid_namespace *ns);
2436 
2437 /* per-UID process charging. */
2438 extern struct user_struct * alloc_uid(kuid_t);
2439 static inline struct user_struct *get_uid(struct user_struct *u)
2440 {
2441 	atomic_inc(&u->__count);
2442 	return u;
2443 }
2444 extern void free_uid(struct user_struct *);
2445 
2446 #include <asm/current.h>
2447 
2448 extern void xtime_update(unsigned long ticks);
2449 
2450 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2451 extern int wake_up_process(struct task_struct *tsk);
2452 extern void wake_up_new_task(struct task_struct *tsk);
2453 #ifdef CONFIG_SMP
2454  extern void kick_process(struct task_struct *tsk);
2455 #else
2456  static inline void kick_process(struct task_struct *tsk) { }
2457 #endif
2458 extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
2459 extern void sched_dead(struct task_struct *p);
2460 
2461 extern void proc_caches_init(void);
2462 extern void flush_signals(struct task_struct *);
2463 extern void ignore_signals(struct task_struct *);
2464 extern void flush_signal_handlers(struct task_struct *, int force_default);
2465 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2466 
2467 static inline int kernel_dequeue_signal(siginfo_t *info)
2468 {
2469 	struct task_struct *tsk = current;
2470 	siginfo_t __info;
2471 	int ret;
2472 
2473 	spin_lock_irq(&tsk->sighand->siglock);
2474 	ret = dequeue_signal(tsk, &tsk->blocked, info ?: &__info);
2475 	spin_unlock_irq(&tsk->sighand->siglock);
2476 
2477 	return ret;
2478 }
2479 
2480 static inline void kernel_signal_stop(void)
2481 {
2482 	spin_lock_irq(&current->sighand->siglock);
2483 	if (current->jobctl & JOBCTL_STOP_DEQUEUED)
2484 		__set_current_state(TASK_STOPPED);
2485 	spin_unlock_irq(&current->sighand->siglock);
2486 
2487 	schedule();
2488 }
2489 
2490 extern void release_task(struct task_struct * p);
2491 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2492 extern int force_sigsegv(int, struct task_struct *);
2493 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2494 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2495 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2496 extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *,
2497 				const struct cred *, u32);
2498 extern int kill_pgrp(struct pid *pid, int sig, int priv);
2499 extern int kill_pid(struct pid *pid, int sig, int priv);
2500 extern int kill_proc_info(int, struct siginfo *, pid_t);
2501 extern __must_check bool do_notify_parent(struct task_struct *, int);
2502 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2503 extern void force_sig(int, struct task_struct *);
2504 extern int send_sig(int, struct task_struct *, int);
2505 extern int zap_other_threads(struct task_struct *p);
2506 extern struct sigqueue *sigqueue_alloc(void);
2507 extern void sigqueue_free(struct sigqueue *);
2508 extern int send_sigqueue(struct sigqueue *,  struct task_struct *, int group);
2509 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2510 
2511 static inline void restore_saved_sigmask(void)
2512 {
2513 	if (test_and_clear_restore_sigmask())
2514 		__set_current_blocked(&current->saved_sigmask);
2515 }
2516 
2517 static inline sigset_t *sigmask_to_save(void)
2518 {
2519 	sigset_t *res = &current->blocked;
2520 	if (unlikely(test_restore_sigmask()))
2521 		res = &current->saved_sigmask;
2522 	return res;
2523 }
2524 
2525 static inline int kill_cad_pid(int sig, int priv)
2526 {
2527 	return kill_pid(cad_pid, sig, priv);
2528 }
2529 
2530 /* These can be the second arg to send_sig_info/send_group_sig_info.  */
2531 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
2532 #define SEND_SIG_PRIV	((struct siginfo *) 1)
2533 #define SEND_SIG_FORCED	((struct siginfo *) 2)
2534 
2535 /*
2536  * True if we are on the alternate signal stack.
2537  */
2538 static inline int on_sig_stack(unsigned long sp)
2539 {
2540 #ifdef CONFIG_STACK_GROWSUP
2541 	return sp >= current->sas_ss_sp &&
2542 		sp - current->sas_ss_sp < current->sas_ss_size;
2543 #else
2544 	return sp > current->sas_ss_sp &&
2545 		sp - current->sas_ss_sp <= current->sas_ss_size;
2546 #endif
2547 }
2548 
2549 static inline int sas_ss_flags(unsigned long sp)
2550 {
2551 	if (!current->sas_ss_size)
2552 		return SS_DISABLE;
2553 
2554 	return on_sig_stack(sp) ? SS_ONSTACK : 0;
2555 }
2556 
2557 static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig)
2558 {
2559 	if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp))
2560 #ifdef CONFIG_STACK_GROWSUP
2561 		return current->sas_ss_sp;
2562 #else
2563 		return current->sas_ss_sp + current->sas_ss_size;
2564 #endif
2565 	return sp;
2566 }
2567 
2568 /*
2569  * Routines for handling mm_structs
2570  */
2571 extern struct mm_struct * mm_alloc(void);
2572 
2573 /* mmdrop drops the mm and the page tables */
2574 extern void __mmdrop(struct mm_struct *);
2575 static inline void mmdrop(struct mm_struct * mm)
2576 {
2577 	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2578 		__mmdrop(mm);
2579 }
2580 
2581 /* mmput gets rid of the mappings and all user-space */
2582 extern void mmput(struct mm_struct *);
2583 /* Grab a reference to a task's mm, if it is not already going away */
2584 extern struct mm_struct *get_task_mm(struct task_struct *task);
2585 /*
2586  * Grab a reference to a task's mm, if it is not already going away
2587  * and ptrace_may_access with the mode parameter passed to it
2588  * succeeds.
2589  */
2590 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode);
2591 /* Remove the current tasks stale references to the old mm_struct */
2592 extern void mm_release(struct task_struct *, struct mm_struct *);
2593 
2594 #ifdef CONFIG_HAVE_COPY_THREAD_TLS
2595 extern int copy_thread_tls(unsigned long, unsigned long, unsigned long,
2596 			struct task_struct *, unsigned long);
2597 #else
2598 extern int copy_thread(unsigned long, unsigned long, unsigned long,
2599 			struct task_struct *);
2600 
2601 /* Architectures that haven't opted into copy_thread_tls get the tls argument
2602  * via pt_regs, so ignore the tls argument passed via C. */
2603 static inline int copy_thread_tls(
2604 		unsigned long clone_flags, unsigned long sp, unsigned long arg,
2605 		struct task_struct *p, unsigned long tls)
2606 {
2607 	return copy_thread(clone_flags, sp, arg, p);
2608 }
2609 #endif
2610 extern void flush_thread(void);
2611 extern void exit_thread(void);
2612 
2613 extern void exit_files(struct task_struct *);
2614 extern void __cleanup_sighand(struct sighand_struct *);
2615 
2616 extern void exit_itimers(struct signal_struct *);
2617 extern void flush_itimer_signals(void);
2618 
2619 extern void do_group_exit(int);
2620 
2621 extern int do_execve(struct filename *,
2622 		     const char __user * const __user *,
2623 		     const char __user * const __user *);
2624 extern int do_execveat(int, struct filename *,
2625 		       const char __user * const __user *,
2626 		       const char __user * const __user *,
2627 		       int);
2628 extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long);
2629 extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
2630 struct task_struct *fork_idle(int);
2631 extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
2632 
2633 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
2634 static inline void set_task_comm(struct task_struct *tsk, const char *from)
2635 {
2636 	__set_task_comm(tsk, from, false);
2637 }
2638 extern char *get_task_comm(char *to, struct task_struct *tsk);
2639 
2640 #ifdef CONFIG_SMP
2641 void scheduler_ipi(void);
2642 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2643 #else
2644 static inline void scheduler_ipi(void) { }
2645 static inline unsigned long wait_task_inactive(struct task_struct *p,
2646 					       long match_state)
2647 {
2648 	return 1;
2649 }
2650 #endif
2651 
2652 #define tasklist_empty() \
2653 	list_empty(&init_task.tasks)
2654 
2655 #define next_task(p) \
2656 	list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2657 
2658 #define for_each_process(p) \
2659 	for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2660 
2661 extern bool current_is_single_threaded(void);
2662 
2663 /*
2664  * Careful: do_each_thread/while_each_thread is a double loop so
2665  *          'break' will not work as expected - use goto instead.
2666  */
2667 #define do_each_thread(g, t) \
2668 	for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2669 
2670 #define while_each_thread(g, t) \
2671 	while ((t = next_thread(t)) != g)
2672 
2673 #define __for_each_thread(signal, t)	\
2674 	list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node)
2675 
2676 #define for_each_thread(p, t)		\
2677 	__for_each_thread((p)->signal, t)
2678 
2679 /* Careful: this is a double loop, 'break' won't work as expected. */
2680 #define for_each_process_thread(p, t)	\
2681 	for_each_process(p) for_each_thread(p, t)
2682 
2683 static inline int get_nr_threads(struct task_struct *tsk)
2684 {
2685 	return tsk->signal->nr_threads;
2686 }
2687 
2688 static inline bool thread_group_leader(struct task_struct *p)
2689 {
2690 	return p->exit_signal >= 0;
2691 }
2692 
2693 /* Do to the insanities of de_thread it is possible for a process
2694  * to have the pid of the thread group leader without actually being
2695  * the thread group leader.  For iteration through the pids in proc
2696  * all we care about is that we have a task with the appropriate
2697  * pid, we don't actually care if we have the right task.
2698  */
2699 static inline bool has_group_leader_pid(struct task_struct *p)
2700 {
2701 	return task_pid(p) == p->signal->leader_pid;
2702 }
2703 
2704 static inline
2705 bool same_thread_group(struct task_struct *p1, struct task_struct *p2)
2706 {
2707 	return p1->signal == p2->signal;
2708 }
2709 
2710 static inline struct task_struct *next_thread(const struct task_struct *p)
2711 {
2712 	return list_entry_rcu(p->thread_group.next,
2713 			      struct task_struct, thread_group);
2714 }
2715 
2716 static inline int thread_group_empty(struct task_struct *p)
2717 {
2718 	return list_empty(&p->thread_group);
2719 }
2720 
2721 #define delay_group_leader(p) \
2722 		(thread_group_leader(p) && !thread_group_empty(p))
2723 
2724 /*
2725  * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2726  * subscriptions and synchronises with wait4().  Also used in procfs.  Also
2727  * pins the final release of task.io_context.  Also protects ->cpuset and
2728  * ->cgroup.subsys[]. And ->vfork_done.
2729  *
2730  * Nests both inside and outside of read_lock(&tasklist_lock).
2731  * It must not be nested with write_lock_irq(&tasklist_lock),
2732  * neither inside nor outside.
2733  */
2734 static inline void task_lock(struct task_struct *p)
2735 {
2736 	spin_lock(&p->alloc_lock);
2737 }
2738 
2739 static inline void task_unlock(struct task_struct *p)
2740 {
2741 	spin_unlock(&p->alloc_lock);
2742 }
2743 
2744 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2745 							unsigned long *flags);
2746 
2747 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2748 						       unsigned long *flags)
2749 {
2750 	struct sighand_struct *ret;
2751 
2752 	ret = __lock_task_sighand(tsk, flags);
2753 	(void)__cond_lock(&tsk->sighand->siglock, ret);
2754 	return ret;
2755 }
2756 
2757 static inline void unlock_task_sighand(struct task_struct *tsk,
2758 						unsigned long *flags)
2759 {
2760 	spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2761 }
2762 
2763 /**
2764  * threadgroup_change_begin - mark the beginning of changes to a threadgroup
2765  * @tsk: task causing the changes
2766  *
2767  * All operations which modify a threadgroup - a new thread joining the
2768  * group, death of a member thread (the assertion of PF_EXITING) and
2769  * exec(2) dethreading the process and replacing the leader - are wrapped
2770  * by threadgroup_change_{begin|end}().  This is to provide a place which
2771  * subsystems needing threadgroup stability can hook into for
2772  * synchronization.
2773  */
2774 static inline void threadgroup_change_begin(struct task_struct *tsk)
2775 {
2776 	might_sleep();
2777 	cgroup_threadgroup_change_begin(tsk);
2778 }
2779 
2780 /**
2781  * threadgroup_change_end - mark the end of changes to a threadgroup
2782  * @tsk: task causing the changes
2783  *
2784  * See threadgroup_change_begin().
2785  */
2786 static inline void threadgroup_change_end(struct task_struct *tsk)
2787 {
2788 	cgroup_threadgroup_change_end(tsk);
2789 }
2790 
2791 #ifndef __HAVE_THREAD_FUNCTIONS
2792 
2793 #define task_thread_info(task)	((struct thread_info *)(task)->stack)
2794 #define task_stack_page(task)	((task)->stack)
2795 
2796 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2797 {
2798 	*task_thread_info(p) = *task_thread_info(org);
2799 	task_thread_info(p)->task = p;
2800 }
2801 
2802 /*
2803  * Return the address of the last usable long on the stack.
2804  *
2805  * When the stack grows down, this is just above the thread
2806  * info struct. Going any lower will corrupt the threadinfo.
2807  *
2808  * When the stack grows up, this is the highest address.
2809  * Beyond that position, we corrupt data on the next page.
2810  */
2811 static inline unsigned long *end_of_stack(struct task_struct *p)
2812 {
2813 #ifdef CONFIG_STACK_GROWSUP
2814 	return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1;
2815 #else
2816 	return (unsigned long *)(task_thread_info(p) + 1);
2817 #endif
2818 }
2819 
2820 #endif
2821 #define task_stack_end_corrupted(task) \
2822 		(*(end_of_stack(task)) != STACK_END_MAGIC)
2823 
2824 static inline int object_is_on_stack(void *obj)
2825 {
2826 	void *stack = task_stack_page(current);
2827 
2828 	return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2829 }
2830 
2831 extern void thread_info_cache_init(void);
2832 
2833 #ifdef CONFIG_DEBUG_STACK_USAGE
2834 static inline unsigned long stack_not_used(struct task_struct *p)
2835 {
2836 	unsigned long *n = end_of_stack(p);
2837 
2838 	do { 	/* Skip over canary */
2839 		n++;
2840 	} while (!*n);
2841 
2842 	return (unsigned long)n - (unsigned long)end_of_stack(p);
2843 }
2844 #endif
2845 extern void set_task_stack_end_magic(struct task_struct *tsk);
2846 
2847 /* set thread flags in other task's structures
2848  * - see asm/thread_info.h for TIF_xxxx flags available
2849  */
2850 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2851 {
2852 	set_ti_thread_flag(task_thread_info(tsk), flag);
2853 }
2854 
2855 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2856 {
2857 	clear_ti_thread_flag(task_thread_info(tsk), flag);
2858 }
2859 
2860 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2861 {
2862 	return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2863 }
2864 
2865 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2866 {
2867 	return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2868 }
2869 
2870 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2871 {
2872 	return test_ti_thread_flag(task_thread_info(tsk), flag);
2873 }
2874 
2875 static inline void set_tsk_need_resched(struct task_struct *tsk)
2876 {
2877 	set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2878 }
2879 
2880 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2881 {
2882 	clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2883 }
2884 
2885 static inline int test_tsk_need_resched(struct task_struct *tsk)
2886 {
2887 	return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2888 }
2889 
2890 static inline int restart_syscall(void)
2891 {
2892 	set_tsk_thread_flag(current, TIF_SIGPENDING);
2893 	return -ERESTARTNOINTR;
2894 }
2895 
2896 static inline int signal_pending(struct task_struct *p)
2897 {
2898 	return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2899 }
2900 
2901 static inline int __fatal_signal_pending(struct task_struct *p)
2902 {
2903 	return unlikely(sigismember(&p->pending.signal, SIGKILL));
2904 }
2905 
2906 static inline int fatal_signal_pending(struct task_struct *p)
2907 {
2908 	return signal_pending(p) && __fatal_signal_pending(p);
2909 }
2910 
2911 static inline int signal_pending_state(long state, struct task_struct *p)
2912 {
2913 	if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2914 		return 0;
2915 	if (!signal_pending(p))
2916 		return 0;
2917 
2918 	return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2919 }
2920 
2921 /*
2922  * cond_resched() and cond_resched_lock(): latency reduction via
2923  * explicit rescheduling in places that are safe. The return
2924  * value indicates whether a reschedule was done in fact.
2925  * cond_resched_lock() will drop the spinlock before scheduling,
2926  * cond_resched_softirq() will enable bhs before scheduling.
2927  */
2928 extern int _cond_resched(void);
2929 
2930 #define cond_resched() ({			\
2931 	___might_sleep(__FILE__, __LINE__, 0);	\
2932 	_cond_resched();			\
2933 })
2934 
2935 extern int __cond_resched_lock(spinlock_t *lock);
2936 
2937 #define cond_resched_lock(lock) ({				\
2938 	___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
2939 	__cond_resched_lock(lock);				\
2940 })
2941 
2942 extern int __cond_resched_softirq(void);
2943 
2944 #define cond_resched_softirq() ({					\
2945 	___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET);	\
2946 	__cond_resched_softirq();					\
2947 })
2948 
2949 static inline void cond_resched_rcu(void)
2950 {
2951 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
2952 	rcu_read_unlock();
2953 	cond_resched();
2954 	rcu_read_lock();
2955 #endif
2956 }
2957 
2958 /*
2959  * Does a critical section need to be broken due to another
2960  * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2961  * but a general need for low latency)
2962  */
2963 static inline int spin_needbreak(spinlock_t *lock)
2964 {
2965 #ifdef CONFIG_PREEMPT
2966 	return spin_is_contended(lock);
2967 #else
2968 	return 0;
2969 #endif
2970 }
2971 
2972 /*
2973  * Idle thread specific functions to determine the need_resched
2974  * polling state.
2975  */
2976 #ifdef TIF_POLLING_NRFLAG
2977 static inline int tsk_is_polling(struct task_struct *p)
2978 {
2979 	return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG);
2980 }
2981 
2982 static inline void __current_set_polling(void)
2983 {
2984 	set_thread_flag(TIF_POLLING_NRFLAG);
2985 }
2986 
2987 static inline bool __must_check current_set_polling_and_test(void)
2988 {
2989 	__current_set_polling();
2990 
2991 	/*
2992 	 * Polling state must be visible before we test NEED_RESCHED,
2993 	 * paired by resched_curr()
2994 	 */
2995 	smp_mb__after_atomic();
2996 
2997 	return unlikely(tif_need_resched());
2998 }
2999 
3000 static inline void __current_clr_polling(void)
3001 {
3002 	clear_thread_flag(TIF_POLLING_NRFLAG);
3003 }
3004 
3005 static inline bool __must_check current_clr_polling_and_test(void)
3006 {
3007 	__current_clr_polling();
3008 
3009 	/*
3010 	 * Polling state must be visible before we test NEED_RESCHED,
3011 	 * paired by resched_curr()
3012 	 */
3013 	smp_mb__after_atomic();
3014 
3015 	return unlikely(tif_need_resched());
3016 }
3017 
3018 #else
3019 static inline int tsk_is_polling(struct task_struct *p) { return 0; }
3020 static inline void __current_set_polling(void) { }
3021 static inline void __current_clr_polling(void) { }
3022 
3023 static inline bool __must_check current_set_polling_and_test(void)
3024 {
3025 	return unlikely(tif_need_resched());
3026 }
3027 static inline bool __must_check current_clr_polling_and_test(void)
3028 {
3029 	return unlikely(tif_need_resched());
3030 }
3031 #endif
3032 
3033 static inline void current_clr_polling(void)
3034 {
3035 	__current_clr_polling();
3036 
3037 	/*
3038 	 * Ensure we check TIF_NEED_RESCHED after we clear the polling bit.
3039 	 * Once the bit is cleared, we'll get IPIs with every new
3040 	 * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also
3041 	 * fold.
3042 	 */
3043 	smp_mb(); /* paired with resched_curr() */
3044 
3045 	preempt_fold_need_resched();
3046 }
3047 
3048 static __always_inline bool need_resched(void)
3049 {
3050 	return unlikely(tif_need_resched());
3051 }
3052 
3053 /*
3054  * Thread group CPU time accounting.
3055  */
3056 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
3057 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
3058 
3059 /*
3060  * Reevaluate whether the task has signals pending delivery.
3061  * Wake the task if so.
3062  * This is required every time the blocked sigset_t changes.
3063  * callers must hold sighand->siglock.
3064  */
3065 extern void recalc_sigpending_and_wake(struct task_struct *t);
3066 extern void recalc_sigpending(void);
3067 
3068 extern void signal_wake_up_state(struct task_struct *t, unsigned int state);
3069 
3070 static inline void signal_wake_up(struct task_struct *t, bool resume)
3071 {
3072 	signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
3073 }
3074 static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
3075 {
3076 	signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
3077 }
3078 
3079 /*
3080  * Wrappers for p->thread_info->cpu access. No-op on UP.
3081  */
3082 #ifdef CONFIG_SMP
3083 
3084 static inline unsigned int task_cpu(const struct task_struct *p)
3085 {
3086 	return task_thread_info(p)->cpu;
3087 }
3088 
3089 static inline int task_node(const struct task_struct *p)
3090 {
3091 	return cpu_to_node(task_cpu(p));
3092 }
3093 
3094 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
3095 
3096 #else
3097 
3098 static inline unsigned int task_cpu(const struct task_struct *p)
3099 {
3100 	return 0;
3101 }
3102 
3103 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
3104 {
3105 }
3106 
3107 #endif /* CONFIG_SMP */
3108 
3109 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
3110 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
3111 
3112 #ifdef CONFIG_CGROUP_SCHED
3113 extern struct task_group root_task_group;
3114 #endif /* CONFIG_CGROUP_SCHED */
3115 
3116 extern int task_can_switch_user(struct user_struct *up,
3117 					struct task_struct *tsk);
3118 
3119 #ifdef CONFIG_TASK_XACCT
3120 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3121 {
3122 	tsk->ioac.rchar += amt;
3123 }
3124 
3125 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3126 {
3127 	tsk->ioac.wchar += amt;
3128 }
3129 
3130 static inline void inc_syscr(struct task_struct *tsk)
3131 {
3132 	tsk->ioac.syscr++;
3133 }
3134 
3135 static inline void inc_syscw(struct task_struct *tsk)
3136 {
3137 	tsk->ioac.syscw++;
3138 }
3139 #else
3140 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3141 {
3142 }
3143 
3144 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3145 {
3146 }
3147 
3148 static inline void inc_syscr(struct task_struct *tsk)
3149 {
3150 }
3151 
3152 static inline void inc_syscw(struct task_struct *tsk)
3153 {
3154 }
3155 #endif
3156 
3157 #ifndef TASK_SIZE_OF
3158 #define TASK_SIZE_OF(tsk)	TASK_SIZE
3159 #endif
3160 
3161 #ifdef CONFIG_MEMCG
3162 extern void mm_update_next_owner(struct mm_struct *mm);
3163 #else
3164 static inline void mm_update_next_owner(struct mm_struct *mm)
3165 {
3166 }
3167 #endif /* CONFIG_MEMCG */
3168 
3169 static inline unsigned long task_rlimit(const struct task_struct *tsk,
3170 		unsigned int limit)
3171 {
3172 	return READ_ONCE(tsk->signal->rlim[limit].rlim_cur);
3173 }
3174 
3175 static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
3176 		unsigned int limit)
3177 {
3178 	return READ_ONCE(tsk->signal->rlim[limit].rlim_max);
3179 }
3180 
3181 static inline unsigned long rlimit(unsigned int limit)
3182 {
3183 	return task_rlimit(current, limit);
3184 }
3185 
3186 static inline unsigned long rlimit_max(unsigned int limit)
3187 {
3188 	return task_rlimit_max(current, limit);
3189 }
3190 
3191 #endif
3192