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