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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 #include <asm/param.h> /* for HZ */
9
10 #include <linux/capability.h>
11 #include <linux/threads.h>
12 #include <linux/kernel.h>
13 #include <linux/types.h>
14 #include <linux/timex.h>
15 #include <linux/jiffies.h>
16 #include <linux/mutex.h>
17 #include <linux/plist.h>
18 #include <linux/rbtree.h>
19 #include <linux/thread_info.h>
20 #include <linux/cpumask.h>
21 #include <linux/errno.h>
22 #include <linux/nodemask.h>
23 #include <linux/mm_types.h>
24 #include <linux/preempt.h>
25
26 #include <asm/page.h>
27 #include <asm/ptrace.h>
28
29 #include <linux/smp.h>
30 #include <linux/sem.h>
31 #include <linux/shm.h>
32 #include <linux/signal.h>
33 #include <linux/compiler.h>
34 #include <linux/completion.h>
35 #include <linux/signal_types.h>
36 #include <linux/pid.h>
37 #include <linux/percpu.h>
38 #include <linux/topology.h>
39 #include <linux/seccomp.h>
40 #include <linux/rcupdate.h>
41 #include <linux/rculist.h>
42 #include <linux/rtmutex.h>
43
44 #include <linux/time.h>
45 #include <linux/param.h>
46 #include <linux/resource.h>
47 #include <linux/timer.h>
48 #include <linux/hrtimer.h>
49 #include <linux/kcov.h>
50 #include <linux/task_io_accounting.h>
51 #include <linux/latencytop.h>
52 #include <linux/cred.h>
53 #include <linux/llist.h>
54 #include <linux/uidgid.h>
55 #include <linux/gfp.h>
56 #include <linux/topology.h>
57 #include <linux/magic.h>
58 #include <linux/cgroup-defs.h>
59
60 #include <asm/processor.h>
61
62 struct sched_attr;
63 struct sched_param;
64
65 struct futex_pi_state;
66 struct robust_list_head;
67 struct bio_list;
68 struct fs_struct;
69 struct perf_event_context;
70 struct blk_plug;
71 struct filename;
72 struct nameidata;
73
74 /*
75 * These are the constant used to fake the fixed-point load-average
76 * counting. Some notes:
77 * - 11 bit fractions expand to 22 bits by the multiplies: this gives
78 * a load-average precision of 10 bits integer + 11 bits fractional
79 * - if you want to count load-averages more often, you need more
80 * precision, or rounding will get you. With 2-second counting freq,
81 * the EXP_n values would be 1981, 2034 and 2043 if still using only
82 * 11 bit fractions.
83 */
84 extern unsigned long avenrun[]; /* Load averages */
85 extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
86
87 #define FSHIFT 11 /* nr of bits of precision */
88 #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
89 #define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */
90 #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
91 #define EXP_5 2014 /* 1/exp(5sec/5min) */
92 #define EXP_15 2037 /* 1/exp(5sec/15min) */
93
94 #define CALC_LOAD(load,exp,n) \
95 load *= exp; \
96 load += n*(FIXED_1-exp); \
97 load >>= FSHIFT;
98
99 extern unsigned long total_forks;
100 extern int nr_threads;
101 DECLARE_PER_CPU(unsigned long, process_counts);
102 extern int nr_processes(void);
103 extern unsigned long nr_running(void);
104 extern bool single_task_running(void);
105 extern unsigned long nr_iowait(void);
106 extern unsigned long nr_iowait_cpu(int cpu);
107 extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load);
108
109 extern void calc_global_load(unsigned long ticks);
110
111 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
112 extern void cpu_load_update_nohz_start(void);
113 extern void cpu_load_update_nohz_stop(void);
114 #else
115 static inline void cpu_load_update_nohz_start(void) { }
116 static inline void cpu_load_update_nohz_stop(void) { }
117 #endif
118
119 extern void dump_cpu_task(int cpu);
120
121 struct seq_file;
122 struct cfs_rq;
123 struct task_group;
124 #ifdef CONFIG_SCHED_DEBUG
125 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
126 extern void proc_sched_set_task(struct task_struct *p);
127 #endif
128
129 /*
130 * Task state bitmask. NOTE! These bits are also
131 * encoded in fs/proc/array.c: get_task_state().
132 *
133 * We have two separate sets of flags: task->state
134 * is about runnability, while task->exit_state are
135 * about the task exiting. Confusing, but this way
136 * modifying one set can't modify the other one by
137 * mistake.
138 */
139 #define TASK_RUNNING 0
140 #define TASK_INTERRUPTIBLE 1
141 #define TASK_UNINTERRUPTIBLE 2
142 #define __TASK_STOPPED 4
143 #define __TASK_TRACED 8
144 /* in tsk->exit_state */
145 #define EXIT_DEAD 16
146 #define EXIT_ZOMBIE 32
147 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD)
148 /* in tsk->state again */
149 #define TASK_DEAD 64
150 #define TASK_WAKEKILL 128
151 #define TASK_WAKING 256
152 #define TASK_PARKED 512
153 #define TASK_NOLOAD 1024
154 #define TASK_NEW 2048
155 #define TASK_STATE_MAX 4096
156
157 #define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPNn"
158
159 /* Convenience macros for the sake of set_current_state */
160 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
161 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
162 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED)
163
164 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
165
166 /* Convenience macros for the sake of wake_up */
167 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
168 #define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
169
170 /* get_task_state() */
171 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \
172 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
173 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD)
174
175 #define task_is_traced(task) ((task->state & __TASK_TRACED) != 0)
176 #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0)
177 #define task_is_stopped_or_traced(task) \
178 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
179 #define task_contributes_to_load(task) \
180 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
181 (task->flags & PF_FROZEN) == 0 && \
182 (task->state & TASK_NOLOAD) == 0)
183
184 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
185
186 #define __set_current_state(state_value) \
187 do { \
188 current->task_state_change = _THIS_IP_; \
189 current->state = (state_value); \
190 } while (0)
191 #define set_current_state(state_value) \
192 do { \
193 current->task_state_change = _THIS_IP_; \
194 smp_store_mb(current->state, (state_value)); \
195 } while (0)
196
197 #else
198 /*
199 * set_current_state() includes a barrier so that the write of current->state
200 * is correctly serialised wrt the caller's subsequent test of whether to
201 * actually sleep:
202 *
203 * for (;;) {
204 * set_current_state(TASK_UNINTERRUPTIBLE);
205 * if (!need_sleep)
206 * break;
207 *
208 * schedule();
209 * }
210 * __set_current_state(TASK_RUNNING);
211 *
212 * If the caller does not need such serialisation (because, for instance, the
213 * condition test and condition change and wakeup are under the same lock) then
214 * use __set_current_state().
215 *
216 * The above is typically ordered against the wakeup, which does:
217 *
218 * need_sleep = false;
219 * wake_up_state(p, TASK_UNINTERRUPTIBLE);
220 *
221 * Where wake_up_state() (and all other wakeup primitives) imply enough
222 * barriers to order the store of the variable against wakeup.
223 *
224 * Wakeup will do: if (@state & p->state) p->state = TASK_RUNNING, that is,
225 * once it observes the TASK_UNINTERRUPTIBLE store the waking CPU can issue a
226 * TASK_RUNNING store which can collide with __set_current_state(TASK_RUNNING).
227 *
228 * This is obviously fine, since they both store the exact same value.
229 *
230 * Also see the comments of try_to_wake_up().
231 */
232 #define __set_current_state(state_value) \
233 do { current->state = (state_value); } while (0)
234 #define set_current_state(state_value) \
235 smp_store_mb(current->state, (state_value))
236
237 #endif
238
239 /* Task command name length */
240 #define TASK_COMM_LEN 16
241
242 #include <linux/spinlock.h>
243
244 /*
245 * This serializes "schedule()" and also protects
246 * the run-queue from deletions/modifications (but
247 * _adding_ to the beginning of the run-queue has
248 * a separate lock).
249 */
250 extern rwlock_t tasklist_lock;
251 extern spinlock_t mmlist_lock;
252
253 struct task_struct;
254
255 #ifdef CONFIG_PROVE_RCU
256 extern int lockdep_tasklist_lock_is_held(void);
257 #endif /* #ifdef CONFIG_PROVE_RCU */
258
259 extern void sched_init(void);
260 extern void sched_init_smp(void);
261 extern asmlinkage void schedule_tail(struct task_struct *prev);
262 extern void init_idle(struct task_struct *idle, int cpu);
263 extern void init_idle_bootup_task(struct task_struct *idle);
264
265 extern cpumask_var_t cpu_isolated_map;
266
267 extern int runqueue_is_locked(int cpu);
268
269 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
270 extern void nohz_balance_enter_idle(int cpu);
271 extern void set_cpu_sd_state_idle(void);
272 extern int get_nohz_timer_target(void);
273 #else
274 static inline void nohz_balance_enter_idle(int cpu) { }
275 static inline void set_cpu_sd_state_idle(void) { }
276 #endif
277
278 /*
279 * Only dump TASK_* tasks. (0 for all tasks)
280 */
281 extern void show_state_filter(unsigned long state_filter);
282
283 static inline void show_state(void)
284 {
285 show_state_filter(0);
286 }
287
288 extern void show_regs(struct pt_regs *);
289
290 /*
291 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
292 * task), SP is the stack pointer of the first frame that should be shown in the back
293 * trace (or NULL if the entire call-chain of the task should be shown).
294 */
295 extern void show_stack(struct task_struct *task, unsigned long *sp);
296
297 extern void cpu_init (void);
298 extern void trap_init(void);
299 extern void update_process_times(int user);
300 extern void scheduler_tick(void);
301 extern int sched_cpu_starting(unsigned int cpu);
302 extern int sched_cpu_activate(unsigned int cpu);
303 extern int sched_cpu_deactivate(unsigned int cpu);
304
305 #ifdef CONFIG_HOTPLUG_CPU
306 extern int sched_cpu_dying(unsigned int cpu);
307 #else
308 # define sched_cpu_dying NULL
309 #endif
310
311 extern void sched_show_task(struct task_struct *p);
312
313 #ifdef CONFIG_LOCKUP_DETECTOR
314 extern void touch_softlockup_watchdog_sched(void);
315 extern void touch_softlockup_watchdog(void);
316 extern void touch_softlockup_watchdog_sync(void);
317 extern void touch_all_softlockup_watchdogs(void);
318 extern int proc_dowatchdog_thresh(struct ctl_table *table, int write,
319 void __user *buffer,
320 size_t *lenp, loff_t *ppos);
321 extern unsigned int softlockup_panic;
322 extern unsigned int hardlockup_panic;
323 void lockup_detector_init(void);
324 #else
325 static inline void touch_softlockup_watchdog_sched(void)
326 {
327 }
328 static inline void touch_softlockup_watchdog(void)
329 {
330 }
331 static inline void touch_softlockup_watchdog_sync(void)
332 {
333 }
334 static inline void touch_all_softlockup_watchdogs(void)
335 {
336 }
337 static inline void lockup_detector_init(void)
338 {
339 }
340 #endif
341
342 #ifdef CONFIG_DETECT_HUNG_TASK
343 void reset_hung_task_detector(void);
344 #else
345 static inline void reset_hung_task_detector(void)
346 {
347 }
348 #endif
349
350 /* Attach to any functions which should be ignored in wchan output. */
351 #define __sched __attribute__((__section__(".sched.text")))
352
353 /* Linker adds these: start and end of __sched functions */
354 extern char __sched_text_start[], __sched_text_end[];
355
356 /* Is this address in the __sched functions? */
357 extern int in_sched_functions(unsigned long addr);
358
359 #define MAX_SCHEDULE_TIMEOUT LONG_MAX
360 extern signed long schedule_timeout(signed long timeout);
361 extern signed long schedule_timeout_interruptible(signed long timeout);
362 extern signed long schedule_timeout_killable(signed long timeout);
363 extern signed long schedule_timeout_uninterruptible(signed long timeout);
364 extern signed long schedule_timeout_idle(signed long timeout);
365 asmlinkage void schedule(void);
366 extern void schedule_preempt_disabled(void);
367
368 extern int __must_check io_schedule_prepare(void);
369 extern void io_schedule_finish(int token);
370 extern long io_schedule_timeout(long timeout);
371 extern void io_schedule(void);
372
373 void __noreturn do_task_dead(void);
374
375 struct nsproxy;
376 struct user_namespace;
377
378 #ifdef CONFIG_MMU
379 extern void arch_pick_mmap_layout(struct mm_struct *mm);
380 extern unsigned long
381 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
382 unsigned long, unsigned long);
383 extern unsigned long
384 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
385 unsigned long len, unsigned long pgoff,
386 unsigned long flags);
387 #else
388 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
389 #endif
390
391 #define SUID_DUMP_DISABLE 0 /* No setuid dumping */
392 #define SUID_DUMP_USER 1 /* Dump as user of process */
393 #define SUID_DUMP_ROOT 2 /* Dump as root */
394
395 /* mm flags */
396
397 /* for SUID_DUMP_* above */
398 #define MMF_DUMPABLE_BITS 2
399 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
400
401 extern void set_dumpable(struct mm_struct *mm, int value);
402 /*
403 * This returns the actual value of the suid_dumpable flag. For things
404 * that are using this for checking for privilege transitions, it must
405 * test against SUID_DUMP_USER rather than treating it as a boolean
406 * value.
407 */
408 static inline int __get_dumpable(unsigned long mm_flags)
409 {
410 return mm_flags & MMF_DUMPABLE_MASK;
411 }
412
413 static inline int get_dumpable(struct mm_struct *mm)
414 {
415 return __get_dumpable(mm->flags);
416 }
417
418 /* coredump filter bits */
419 #define MMF_DUMP_ANON_PRIVATE 2
420 #define MMF_DUMP_ANON_SHARED 3
421 #define MMF_DUMP_MAPPED_PRIVATE 4
422 #define MMF_DUMP_MAPPED_SHARED 5
423 #define MMF_DUMP_ELF_HEADERS 6
424 #define MMF_DUMP_HUGETLB_PRIVATE 7
425 #define MMF_DUMP_HUGETLB_SHARED 8
426 #define MMF_DUMP_DAX_PRIVATE 9
427 #define MMF_DUMP_DAX_SHARED 10
428
429 #define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS
430 #define MMF_DUMP_FILTER_BITS 9
431 #define MMF_DUMP_FILTER_MASK \
432 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
433 #define MMF_DUMP_FILTER_DEFAULT \
434 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\
435 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
436
437 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
438 # define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS)
439 #else
440 # define MMF_DUMP_MASK_DEFAULT_ELF 0
441 #endif
442 /* leave room for more dump flags */
443 #define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */
444 #define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */
445 /*
446 * This one-shot flag is dropped due to necessity of changing exe once again
447 * on NFS restore
448 */
449 //#define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */
450
451 #define MMF_HAS_UPROBES 19 /* has uprobes */
452 #define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */
453 #define MMF_OOM_SKIP 21 /* mm is of no interest for the OOM killer */
454 #define MMF_UNSTABLE 22 /* mm is unstable for copy_from_user */
455 #define MMF_HUGE_ZERO_PAGE 23 /* mm has ever used the global huge zero page */
456
457 #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
458
459 struct sighand_struct {
460 atomic_t count;
461 struct k_sigaction action[_NSIG];
462 spinlock_t siglock;
463 wait_queue_head_t signalfd_wqh;
464 };
465
466 struct pacct_struct {
467 int ac_flag;
468 long ac_exitcode;
469 unsigned long ac_mem;
470 u64 ac_utime, ac_stime;
471 unsigned long ac_minflt, ac_majflt;
472 };
473
474 struct cpu_itimer {
475 u64 expires;
476 u64 incr;
477 };
478
479 /**
480 * struct prev_cputime - snaphsot of system and user cputime
481 * @utime: time spent in user mode
482 * @stime: time spent in system mode
483 * @lock: protects the above two fields
484 *
485 * Stores previous user/system time values such that we can guarantee
486 * monotonicity.
487 */
488 struct prev_cputime {
489 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
490 u64 utime;
491 u64 stime;
492 raw_spinlock_t lock;
493 #endif
494 };
495
496 static inline void prev_cputime_init(struct prev_cputime *prev)
497 {
498 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
499 prev->utime = prev->stime = 0;
500 raw_spin_lock_init(&prev->lock);
501 #endif
502 }
503
504 /**
505 * struct task_cputime - collected CPU time counts
506 * @utime: time spent in user mode, in nanoseconds
507 * @stime: time spent in kernel mode, in nanoseconds
508 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds
509 *
510 * This structure groups together three kinds of CPU time that are tracked for
511 * threads and thread groups. Most things considering CPU time want to group
512 * these counts together and treat all three of them in parallel.
513 */
514 struct task_cputime {
515 u64 utime;
516 u64 stime;
517 unsigned long long sum_exec_runtime;
518 };
519
520 /* Alternate field names when used to cache expirations. */
521 #define virt_exp utime
522 #define prof_exp stime
523 #define sched_exp sum_exec_runtime
524
525 /*
526 * This is the atomic variant of task_cputime, which can be used for
527 * storing and updating task_cputime statistics without locking.
528 */
529 struct task_cputime_atomic {
530 atomic64_t utime;
531 atomic64_t stime;
532 atomic64_t sum_exec_runtime;
533 };
534
535 #define INIT_CPUTIME_ATOMIC \
536 (struct task_cputime_atomic) { \
537 .utime = ATOMIC64_INIT(0), \
538 .stime = ATOMIC64_INIT(0), \
539 .sum_exec_runtime = ATOMIC64_INIT(0), \
540 }
541
542 #define PREEMPT_DISABLED (PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
543
544 /*
545 * Disable preemption until the scheduler is running -- use an unconditional
546 * value so that it also works on !PREEMPT_COUNT kernels.
547 *
548 * Reset by start_kernel()->sched_init()->init_idle()->init_idle_preempt_count().
549 */
550 #define INIT_PREEMPT_COUNT PREEMPT_OFFSET
551
552 /*
553 * Initial preempt_count value; reflects the preempt_count schedule invariant
554 * which states that during context switches:
555 *
556 * preempt_count() == 2*PREEMPT_DISABLE_OFFSET
557 *
558 * Note: PREEMPT_DISABLE_OFFSET is 0 for !PREEMPT_COUNT kernels.
559 * Note: See finish_task_switch().
560 */
561 #define FORK_PREEMPT_COUNT (2*PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
562
563 /**
564 * struct thread_group_cputimer - thread group interval timer counts
565 * @cputime_atomic: atomic thread group interval timers.
566 * @running: true when there are timers running and
567 * @cputime_atomic receives updates.
568 * @checking_timer: true when a thread in the group is in the
569 * process of checking for thread group timers.
570 *
571 * This structure contains the version of task_cputime, above, that is
572 * used for thread group CPU timer calculations.
573 */
574 struct thread_group_cputimer {
575 struct task_cputime_atomic cputime_atomic;
576 bool running;
577 bool checking_timer;
578 };
579
580 #include <linux/rwsem.h>
581 struct autogroup;
582
583 /*
584 * NOTE! "signal_struct" does not have its own
585 * locking, because a shared signal_struct always
586 * implies a shared sighand_struct, so locking
587 * sighand_struct is always a proper superset of
588 * the locking of signal_struct.
589 */
590 struct signal_struct {
591 atomic_t sigcnt;
592 atomic_t live;
593 int nr_threads;
594 struct list_head thread_head;
595
596 wait_queue_head_t wait_chldexit; /* for wait4() */
597
598 /* current thread group signal load-balancing target: */
599 struct task_struct *curr_target;
600
601 /* shared signal handling: */
602 struct sigpending shared_pending;
603
604 /* thread group exit support */
605 int group_exit_code;
606 /* overloaded:
607 * - notify group_exit_task when ->count is equal to notify_count
608 * - everyone except group_exit_task is stopped during signal delivery
609 * of fatal signals, group_exit_task processes the signal.
610 */
611 int notify_count;
612 struct task_struct *group_exit_task;
613
614 /* thread group stop support, overloads group_exit_code too */
615 int group_stop_count;
616 unsigned int flags; /* see SIGNAL_* flags below */
617
618 /*
619 * PR_SET_CHILD_SUBREAPER marks a process, like a service
620 * manager, to re-parent orphan (double-forking) child processes
621 * to this process instead of 'init'. The service manager is
622 * able to receive SIGCHLD signals and is able to investigate
623 * the process until it calls wait(). All children of this
624 * process will inherit a flag if they should look for a
625 * child_subreaper process at exit.
626 */
627 unsigned int is_child_subreaper:1;
628 unsigned int has_child_subreaper:1;
629
630 #ifdef CONFIG_POSIX_TIMERS
631
632 /* POSIX.1b Interval Timers */
633 int posix_timer_id;
634 struct list_head posix_timers;
635
636 /* ITIMER_REAL timer for the process */
637 struct hrtimer real_timer;
638 ktime_t it_real_incr;
639
640 /*
641 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
642 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
643 * values are defined to 0 and 1 respectively
644 */
645 struct cpu_itimer it[2];
646
647 /*
648 * Thread group totals for process CPU timers.
649 * See thread_group_cputimer(), et al, for details.
650 */
651 struct thread_group_cputimer cputimer;
652
653 /* Earliest-expiration cache. */
654 struct task_cputime cputime_expires;
655
656 struct list_head cpu_timers[3];
657
658 #endif
659
660 struct pid *leader_pid;
661
662 #ifdef CONFIG_NO_HZ_FULL
663 atomic_t tick_dep_mask;
664 #endif
665
666 struct pid *tty_old_pgrp;
667
668 /* boolean value for session group leader */
669 int leader;
670
671 struct tty_struct *tty; /* NULL if no tty */
672
673 #ifdef CONFIG_SCHED_AUTOGROUP
674 struct autogroup *autogroup;
675 #endif
676 /*
677 * Cumulative resource counters for dead threads in the group,
678 * and for reaped dead child processes forked by this group.
679 * Live threads maintain their own counters and add to these
680 * in __exit_signal, except for the group leader.
681 */
682 seqlock_t stats_lock;
683 u64 utime, stime, cutime, cstime;
684 u64 gtime;
685 u64 cgtime;
686 struct prev_cputime prev_cputime;
687 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
688 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
689 unsigned long inblock, oublock, cinblock, coublock;
690 unsigned long maxrss, cmaxrss;
691 struct task_io_accounting ioac;
692
693 /*
694 * Cumulative ns of schedule CPU time fo dead threads in the
695 * group, not including a zombie group leader, (This only differs
696 * from jiffies_to_ns(utime + stime) if sched_clock uses something
697 * other than jiffies.)
698 */
699 unsigned long long sum_sched_runtime;
700
701 /*
702 * We don't bother to synchronize most readers of this at all,
703 * because there is no reader checking a limit that actually needs
704 * to get both rlim_cur and rlim_max atomically, and either one
705 * alone is a single word that can safely be read normally.
706 * getrlimit/setrlimit use task_lock(current->group_leader) to
707 * protect this instead of the siglock, because they really
708 * have no need to disable irqs.
709 */
710 struct rlimit rlim[RLIM_NLIMITS];
711
712 #ifdef CONFIG_BSD_PROCESS_ACCT
713 struct pacct_struct pacct; /* per-process accounting information */
714 #endif
715 #ifdef CONFIG_TASKSTATS
716 struct taskstats *stats;
717 #endif
718 #ifdef CONFIG_AUDIT
719 unsigned audit_tty;
720 struct tty_audit_buf *tty_audit_buf;
721 #endif
722
723 /*
724 * Thread is the potential origin of an oom condition; kill first on
725 * oom
726 */
727 bool oom_flag_origin;
728 short oom_score_adj; /* OOM kill score adjustment */
729 short oom_score_adj_min; /* OOM kill score adjustment min value.
730 * Only settable by CAP_SYS_RESOURCE. */
731 struct mm_struct *oom_mm; /* recorded mm when the thread group got
732 * killed by the oom killer */
733
734 struct mutex cred_guard_mutex; /* guard against foreign influences on
735 * credential calculations
736 * (notably. ptrace) */
737 };
738
739 /*
740 * Bits in flags field of signal_struct.
741 */
742 #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */
743 #define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */
744 #define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */
745 #define SIGNAL_GROUP_COREDUMP 0x00000008 /* coredump in progress */
746 /*
747 * Pending notifications to parent.
748 */
749 #define SIGNAL_CLD_STOPPED 0x00000010
750 #define SIGNAL_CLD_CONTINUED 0x00000020
751 #define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
752
753 #define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */
754
755 #define SIGNAL_STOP_MASK (SIGNAL_CLD_MASK | SIGNAL_STOP_STOPPED | \
756 SIGNAL_STOP_CONTINUED)
757
758 static inline void signal_set_stop_flags(struct signal_struct *sig,
759 unsigned int flags)
760 {
761 WARN_ON(sig->flags & (SIGNAL_GROUP_EXIT|SIGNAL_GROUP_COREDUMP));
762 sig->flags = (sig->flags & ~SIGNAL_STOP_MASK) | flags;
763 }
764
765 /* If true, all threads except ->group_exit_task have pending SIGKILL */
766 static inline int signal_group_exit(const struct signal_struct *sig)
767 {
768 return (sig->flags & SIGNAL_GROUP_EXIT) ||
769 (sig->group_exit_task != NULL);
770 }
771
772 /*
773 * Some day this will be a full-fledged user tracking system..
774 */
775 struct user_struct {
776 atomic_t __count; /* reference count */
777 atomic_t processes; /* How many processes does this user have? */
778 atomic_t sigpending; /* How many pending signals does this user have? */
779 #ifdef CONFIG_FANOTIFY
780 atomic_t fanotify_listeners;
781 #endif
782 #ifdef CONFIG_EPOLL
783 atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
784 #endif
785 #ifdef CONFIG_POSIX_MQUEUE
786 /* protected by mq_lock */
787 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
788 #endif
789 unsigned long locked_shm; /* How many pages of mlocked shm ? */
790 unsigned long unix_inflight; /* How many files in flight in unix sockets */
791 atomic_long_t pipe_bufs; /* how many pages are allocated in pipe buffers */
792
793 #ifdef CONFIG_KEYS
794 struct key *uid_keyring; /* UID specific keyring */
795 struct key *session_keyring; /* UID's default session keyring */
796 #endif
797
798 /* Hash table maintenance information */
799 struct hlist_node uidhash_node;
800 kuid_t uid;
801
802 #if defined(CONFIG_PERF_EVENTS) || defined(CONFIG_BPF_SYSCALL)
803 atomic_long_t locked_vm;
804 #endif
805 };
806
807 extern int uids_sysfs_init(void);
808
809 extern struct user_struct *find_user(kuid_t);
810
811 extern struct user_struct root_user;
812 #define INIT_USER (&root_user)
813
814
815 struct backing_dev_info;
816 struct reclaim_state;
817
818 #ifdef CONFIG_SCHED_INFO
819 struct sched_info {
820 /* cumulative counters */
821 unsigned long pcount; /* # of times run on this cpu */
822 unsigned long long run_delay; /* time spent waiting on a runqueue */
823
824 /* timestamps */
825 unsigned long long last_arrival,/* when we last ran on a cpu */
826 last_queued; /* when we were last queued to run */
827 };
828 #endif /* CONFIG_SCHED_INFO */
829
830 struct task_delay_info;
831
832 static inline int sched_info_on(void)
833 {
834 #ifdef CONFIG_SCHEDSTATS
835 return 1;
836 #elif defined(CONFIG_TASK_DELAY_ACCT)
837 extern int delayacct_on;
838 return delayacct_on;
839 #else
840 return 0;
841 #endif
842 }
843
844 #ifdef CONFIG_SCHEDSTATS
845 void force_schedstat_enabled(void);
846 #endif
847
848 /*
849 * Integer metrics need fixed point arithmetic, e.g., sched/fair
850 * has a few: load, load_avg, util_avg, freq, and capacity.
851 *
852 * We define a basic fixed point arithmetic range, and then formalize
853 * all these metrics based on that basic range.
854 */
855 # define SCHED_FIXEDPOINT_SHIFT 10
856 # define SCHED_FIXEDPOINT_SCALE (1L << SCHED_FIXEDPOINT_SHIFT)
857
858 struct io_context; /* See blkdev.h */
859
860
861 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
862 extern void prefetch_stack(struct task_struct *t);
863 #else
864 static inline void prefetch_stack(struct task_struct *t) { }
865 #endif
866
867 struct audit_context; /* See audit.c */
868 struct mempolicy;
869 struct pipe_inode_info;
870 struct uts_namespace;
871
872 struct load_weight {
873 unsigned long weight;
874 u32 inv_weight;
875 };
876
877 /*
878 * The load_avg/util_avg accumulates an infinite geometric series
879 * (see __update_load_avg() in kernel/sched/fair.c).
880 *
881 * [load_avg definition]
882 *
883 * load_avg = runnable% * scale_load_down(load)
884 *
885 * where runnable% is the time ratio that a sched_entity is runnable.
886 * For cfs_rq, it is the aggregated load_avg of all runnable and
887 * blocked sched_entities.
888 *
889 * load_avg may also take frequency scaling into account:
890 *
891 * load_avg = runnable% * scale_load_down(load) * freq%
892 *
893 * where freq% is the CPU frequency normalized to the highest frequency.
894 *
895 * [util_avg definition]
896 *
897 * util_avg = running% * SCHED_CAPACITY_SCALE
898 *
899 * where running% is the time ratio that a sched_entity is running on
900 * a CPU. For cfs_rq, it is the aggregated util_avg of all runnable
901 * and blocked sched_entities.
902 *
903 * util_avg may also factor frequency scaling and CPU capacity scaling:
904 *
905 * util_avg = running% * SCHED_CAPACITY_SCALE * freq% * capacity%
906 *
907 * where freq% is the same as above, and capacity% is the CPU capacity
908 * normalized to the greatest capacity (due to uarch differences, etc).
909 *
910 * N.B., the above ratios (runnable%, running%, freq%, and capacity%)
911 * themselves are in the range of [0, 1]. To do fixed point arithmetics,
912 * we therefore scale them to as large a range as necessary. This is for
913 * example reflected by util_avg's SCHED_CAPACITY_SCALE.
914 *
915 * [Overflow issue]
916 *
917 * The 64-bit load_sum can have 4353082796 (=2^64/47742/88761) entities
918 * with the highest load (=88761), always runnable on a single cfs_rq,
919 * and should not overflow as the number already hits PID_MAX_LIMIT.
920 *
921 * For all other cases (including 32-bit kernels), struct load_weight's
922 * weight will overflow first before we do, because:
923 *
924 * Max(load_avg) <= Max(load.weight)
925 *
926 * Then it is the load_weight's responsibility to consider overflow
927 * issues.
928 */
929 struct sched_avg {
930 u64 last_update_time, load_sum;
931 u32 util_sum, period_contrib;
932 unsigned long load_avg, util_avg;
933 };
934
935 #ifdef CONFIG_SCHEDSTATS
936 struct sched_statistics {
937 u64 wait_start;
938 u64 wait_max;
939 u64 wait_count;
940 u64 wait_sum;
941 u64 iowait_count;
942 u64 iowait_sum;
943
944 u64 sleep_start;
945 u64 sleep_max;
946 s64 sum_sleep_runtime;
947
948 u64 block_start;
949 u64 block_max;
950 u64 exec_max;
951 u64 slice_max;
952
953 u64 nr_migrations_cold;
954 u64 nr_failed_migrations_affine;
955 u64 nr_failed_migrations_running;
956 u64 nr_failed_migrations_hot;
957 u64 nr_forced_migrations;
958
959 u64 nr_wakeups;
960 u64 nr_wakeups_sync;
961 u64 nr_wakeups_migrate;
962 u64 nr_wakeups_local;
963 u64 nr_wakeups_remote;
964 u64 nr_wakeups_affine;
965 u64 nr_wakeups_affine_attempts;
966 u64 nr_wakeups_passive;
967 u64 nr_wakeups_idle;
968 };
969 #endif
970
971 struct sched_entity {
972 struct load_weight load; /* for load-balancing */
973 struct rb_node run_node;
974 struct list_head group_node;
975 unsigned int on_rq;
976
977 u64 exec_start;
978 u64 sum_exec_runtime;
979 u64 vruntime;
980 u64 prev_sum_exec_runtime;
981
982 u64 nr_migrations;
983
984 #ifdef CONFIG_SCHEDSTATS
985 struct sched_statistics statistics;
986 #endif
987
988 #ifdef CONFIG_FAIR_GROUP_SCHED
989 int depth;
990 struct sched_entity *parent;
991 /* rq on which this entity is (to be) queued: */
992 struct cfs_rq *cfs_rq;
993 /* rq "owned" by this entity/group: */
994 struct cfs_rq *my_q;
995 #endif
996
997 #ifdef CONFIG_SMP
998 /*
999 * Per entity load average tracking.
1000 *
1001 * Put into separate cache line so it does not
1002 * collide with read-mostly values above.
1003 */
1004 struct sched_avg avg ____cacheline_aligned_in_smp;
1005 #endif
1006 };
1007
1008 struct sched_rt_entity {
1009 struct list_head run_list;
1010 unsigned long timeout;
1011 unsigned long watchdog_stamp;
1012 unsigned int time_slice;
1013 unsigned short on_rq;
1014 unsigned short on_list;
1015
1016 struct sched_rt_entity *back;
1017 #ifdef CONFIG_RT_GROUP_SCHED
1018 struct sched_rt_entity *parent;
1019 /* rq on which this entity is (to be) queued: */
1020 struct rt_rq *rt_rq;
1021 /* rq "owned" by this entity/group: */
1022 struct rt_rq *my_q;
1023 #endif
1024 };
1025
1026 struct sched_dl_entity {
1027 struct rb_node rb_node;
1028
1029 /*
1030 * Original scheduling parameters. Copied here from sched_attr
1031 * during sched_setattr(), they will remain the same until
1032 * the next sched_setattr().
1033 */
1034 u64 dl_runtime; /* maximum runtime for each instance */
1035 u64 dl_deadline; /* relative deadline of each instance */
1036 u64 dl_period; /* separation of two instances (period) */
1037 u64 dl_bw; /* dl_runtime / dl_deadline */
1038
1039 /*
1040 * Actual scheduling parameters. Initialized with the values above,
1041 * they are continously updated during task execution. Note that
1042 * the remaining runtime could be < 0 in case we are in overrun.
1043 */
1044 s64 runtime; /* remaining runtime for this instance */
1045 u64 deadline; /* absolute deadline for this instance */
1046 unsigned int flags; /* specifying the scheduler behaviour */
1047
1048 /*
1049 * Some bool flags:
1050 *
1051 * @dl_throttled tells if we exhausted the runtime. If so, the
1052 * task has to wait for a replenishment to be performed at the
1053 * next firing of dl_timer.
1054 *
1055 * @dl_boosted tells if we are boosted due to DI. If so we are
1056 * outside bandwidth enforcement mechanism (but only until we
1057 * exit the critical section);
1058 *
1059 * @dl_yielded tells if task gave up the cpu before consuming
1060 * all its available runtime during the last job.
1061 */
1062 int dl_throttled, dl_boosted, dl_yielded;
1063
1064 /*
1065 * Bandwidth enforcement timer. Each -deadline task has its
1066 * own bandwidth to be enforced, thus we need one timer per task.
1067 */
1068 struct hrtimer dl_timer;
1069 };
1070
1071 union rcu_special {
1072 struct {
1073 u8 blocked;
1074 u8 need_qs;
1075 u8 exp_need_qs;
1076 u8 pad; /* Otherwise the compiler can store garbage here. */
1077 } b; /* Bits. */
1078 u32 s; /* Set of bits. */
1079 };
1080 struct rcu_node;
1081
1082 enum perf_event_task_context {
1083 perf_invalid_context = -1,
1084 perf_hw_context = 0,
1085 perf_sw_context,
1086 perf_nr_task_contexts,
1087 };
1088
1089 struct wake_q_node {
1090 struct wake_q_node *next;
1091 };
1092
1093 /* Track pages that require TLB flushes */
1094 struct tlbflush_unmap_batch {
1095 /*
1096 * Each bit set is a CPU that potentially has a TLB entry for one of
1097 * the PFNs being flushed. See set_tlb_ubc_flush_pending().
1098 */
1099 struct cpumask cpumask;
1100
1101 /* True if any bit in cpumask is set */
1102 bool flush_required;
1103
1104 /*
1105 * If true then the PTE was dirty when unmapped. The entry must be
1106 * flushed before IO is initiated or a stale TLB entry potentially
1107 * allows an update without redirtying the page.
1108 */
1109 bool writable;
1110 };
1111
1112 struct task_struct {
1113 #ifdef CONFIG_THREAD_INFO_IN_TASK
1114 /*
1115 * For reasons of header soup (see current_thread_info()), this
1116 * must be the first element of task_struct.
1117 */
1118 struct thread_info thread_info;
1119 #endif
1120 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
1121 void *stack;
1122 atomic_t usage;
1123 unsigned int flags; /* per process flags, defined below */
1124 unsigned int ptrace;
1125
1126 #ifdef CONFIG_SMP
1127 struct llist_node wake_entry;
1128 int on_cpu;
1129 #ifdef CONFIG_THREAD_INFO_IN_TASK
1130 unsigned int cpu; /* current CPU */
1131 #endif
1132 unsigned int wakee_flips;
1133 unsigned long wakee_flip_decay_ts;
1134 struct task_struct *last_wakee;
1135
1136 int wake_cpu;
1137 #endif
1138 int on_rq;
1139
1140 int prio, static_prio, normal_prio;
1141 unsigned int rt_priority;
1142 const struct sched_class *sched_class;
1143 struct sched_entity se;
1144 struct sched_rt_entity rt;
1145 #ifdef CONFIG_CGROUP_SCHED
1146 struct task_group *sched_task_group;
1147 #endif
1148 struct sched_dl_entity dl;
1149
1150 #ifdef CONFIG_PREEMPT_NOTIFIERS
1151 /* list of struct preempt_notifier: */
1152 struct hlist_head preempt_notifiers;
1153 #endif
1154
1155 #ifdef CONFIG_BLK_DEV_IO_TRACE
1156 unsigned int btrace_seq;
1157 #endif
1158
1159 unsigned int policy;
1160 int nr_cpus_allowed;
1161 cpumask_t cpus_allowed;
1162
1163 #ifdef CONFIG_PREEMPT_RCU
1164 int rcu_read_lock_nesting;
1165 union rcu_special rcu_read_unlock_special;
1166 struct list_head rcu_node_entry;
1167 struct rcu_node *rcu_blocked_node;
1168 #endif /* #ifdef CONFIG_PREEMPT_RCU */
1169 #ifdef CONFIG_TASKS_RCU
1170 unsigned long rcu_tasks_nvcsw;
1171 bool rcu_tasks_holdout;
1172 struct list_head rcu_tasks_holdout_list;
1173 int rcu_tasks_idle_cpu;
1174 #endif /* #ifdef CONFIG_TASKS_RCU */
1175
1176 #ifdef CONFIG_SCHED_INFO
1177 struct sched_info sched_info;
1178 #endif
1179
1180 struct list_head tasks;
1181 #ifdef CONFIG_SMP
1182 struct plist_node pushable_tasks;
1183 struct rb_node pushable_dl_tasks;
1184 #endif
1185
1186 struct mm_struct *mm, *active_mm;
1187
1188 /* Per-thread vma caching: */
1189 struct vmacache vmacache;
1190
1191 #if defined(SPLIT_RSS_COUNTING)
1192 struct task_rss_stat rss_stat;
1193 #endif
1194 /* task state */
1195 int exit_state;
1196 int exit_code, exit_signal;
1197 int pdeath_signal; /* The signal sent when the parent dies */
1198 unsigned long jobctl; /* JOBCTL_*, siglock protected */
1199
1200 /* Used for emulating ABI behavior of previous Linux versions */
1201 unsigned int personality;
1202
1203 /* scheduler bits, serialized by scheduler locks */
1204 unsigned sched_reset_on_fork:1;
1205 unsigned sched_contributes_to_load:1;
1206 unsigned sched_migrated:1;
1207 unsigned sched_remote_wakeup:1;
1208 unsigned :0; /* force alignment to the next boundary */
1209
1210 /* unserialized, strictly 'current' */
1211 unsigned in_execve:1; /* bit to tell LSMs we're in execve */
1212 unsigned in_iowait:1;
1213 #if !defined(TIF_RESTORE_SIGMASK)
1214 unsigned restore_sigmask:1;
1215 #endif
1216 #ifdef CONFIG_MEMCG
1217 unsigned memcg_may_oom:1;
1218 #ifndef CONFIG_SLOB
1219 unsigned memcg_kmem_skip_account:1;
1220 #endif
1221 #endif
1222 #ifdef CONFIG_COMPAT_BRK
1223 unsigned brk_randomized:1;
1224 #endif
1225
1226 unsigned long atomic_flags; /* Flags needing atomic access. */
1227
1228 struct restart_block restart_block;
1229
1230 pid_t pid;
1231 pid_t tgid;
1232
1233 #ifdef CONFIG_CC_STACKPROTECTOR
1234 /* Canary value for the -fstack-protector gcc feature */
1235 unsigned long stack_canary;
1236 #endif
1237 /*
1238 * pointers to (original) parent process, youngest child, younger sibling,
1239 * older sibling, respectively. (p->father can be replaced with
1240 * p->real_parent->pid)
1241 */
1242 struct task_struct __rcu *real_parent; /* real parent process */
1243 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */
1244 /*
1245 * children/sibling forms the list of my natural children
1246 */
1247 struct list_head children; /* list of my children */
1248 struct list_head sibling; /* linkage in my parent's children list */
1249 struct task_struct *group_leader; /* threadgroup leader */
1250
1251 /*
1252 * ptraced is the list of tasks this task is using ptrace on.
1253 * This includes both natural children and PTRACE_ATTACH targets.
1254 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1255 */
1256 struct list_head ptraced;
1257 struct list_head ptrace_entry;
1258
1259 /* PID/PID hash table linkage. */
1260 struct pid_link pids[PIDTYPE_MAX];
1261 struct list_head thread_group;
1262 struct list_head thread_node;
1263
1264 struct completion *vfork_done; /* for vfork() */
1265 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
1266 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
1267
1268 u64 utime, stime;
1269 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
1270 u64 utimescaled, stimescaled;
1271 #endif
1272 u64 gtime;
1273 struct prev_cputime prev_cputime;
1274 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1275 seqcount_t vtime_seqcount;
1276 unsigned long long vtime_snap;
1277 enum {
1278 /* Task is sleeping or running in a CPU with VTIME inactive */
1279 VTIME_INACTIVE = 0,
1280 /* Task runs in userspace in a CPU with VTIME active */
1281 VTIME_USER,
1282 /* Task runs in kernelspace in a CPU with VTIME active */
1283 VTIME_SYS,
1284 } vtime_snap_whence;
1285 #endif
1286
1287 #ifdef CONFIG_NO_HZ_FULL
1288 atomic_t tick_dep_mask;
1289 #endif
1290 unsigned long nvcsw, nivcsw; /* context switch counts */
1291 u64 start_time; /* monotonic time in nsec */
1292 u64 real_start_time; /* boot based time in nsec */
1293 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1294 unsigned long min_flt, maj_flt;
1295
1296 #ifdef CONFIG_POSIX_TIMERS
1297 struct task_cputime cputime_expires;
1298 struct list_head cpu_timers[3];
1299 #endif
1300
1301 /* process credentials */
1302 const struct cred __rcu *ptracer_cred; /* Tracer's credentials at attach */
1303 const struct cred __rcu *real_cred; /* objective and real subjective task
1304 * credentials (COW) */
1305 const struct cred __rcu *cred; /* effective (overridable) subjective task
1306 * credentials (COW) */
1307 char comm[TASK_COMM_LEN]; /* executable name excluding path
1308 - access with [gs]et_task_comm (which lock
1309 it with task_lock())
1310 - initialized normally by setup_new_exec */
1311 /* file system info */
1312 struct nameidata *nameidata;
1313 #ifdef CONFIG_SYSVIPC
1314 /* ipc stuff */
1315 struct sysv_sem sysvsem;
1316 struct sysv_shm sysvshm;
1317 #endif
1318 #ifdef CONFIG_DETECT_HUNG_TASK
1319 /* hung task detection */
1320 unsigned long last_switch_count;
1321 #endif
1322 /* filesystem information */
1323 struct fs_struct *fs;
1324 /* open file information */
1325 struct files_struct *files;
1326 /* namespaces */
1327 struct nsproxy *nsproxy;
1328 /* signal handlers */
1329 struct signal_struct *signal;
1330 struct sighand_struct *sighand;
1331
1332 sigset_t blocked, real_blocked;
1333 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
1334 struct sigpending pending;
1335
1336 unsigned long sas_ss_sp;
1337 size_t sas_ss_size;
1338 unsigned sas_ss_flags;
1339
1340 struct callback_head *task_works;
1341
1342 struct audit_context *audit_context;
1343 #ifdef CONFIG_AUDITSYSCALL
1344 kuid_t loginuid;
1345 unsigned int sessionid;
1346 #endif
1347 struct seccomp seccomp;
1348
1349 /* Thread group tracking */
1350 u32 parent_exec_id;
1351 u32 self_exec_id;
1352 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1353 * mempolicy */
1354 spinlock_t alloc_lock;
1355
1356 /* Protection of the PI data structures: */
1357 raw_spinlock_t pi_lock;
1358
1359 struct wake_q_node wake_q;
1360
1361 #ifdef CONFIG_RT_MUTEXES
1362 /* PI waiters blocked on a rt_mutex held by this task */
1363 struct rb_root pi_waiters;
1364 struct rb_node *pi_waiters_leftmost;
1365 /* Deadlock detection and priority inheritance handling */
1366 struct rt_mutex_waiter *pi_blocked_on;
1367 #endif
1368
1369 #ifdef CONFIG_DEBUG_MUTEXES
1370 /* mutex deadlock detection */
1371 struct mutex_waiter *blocked_on;
1372 #endif
1373 #ifdef CONFIG_TRACE_IRQFLAGS
1374 unsigned int irq_events;
1375 unsigned long hardirq_enable_ip;
1376 unsigned long hardirq_disable_ip;
1377 unsigned int hardirq_enable_event;
1378 unsigned int hardirq_disable_event;
1379 int hardirqs_enabled;
1380 int hardirq_context;
1381 unsigned long softirq_disable_ip;
1382 unsigned long softirq_enable_ip;
1383 unsigned int softirq_disable_event;
1384 unsigned int softirq_enable_event;
1385 int softirqs_enabled;
1386 int softirq_context;
1387 #endif
1388 #ifdef CONFIG_LOCKDEP
1389 # define MAX_LOCK_DEPTH 48UL
1390 u64 curr_chain_key;
1391 int lockdep_depth;
1392 unsigned int lockdep_recursion;
1393 struct held_lock held_locks[MAX_LOCK_DEPTH];
1394 gfp_t lockdep_reclaim_gfp;
1395 #endif
1396 #ifdef CONFIG_UBSAN
1397 unsigned int in_ubsan;
1398 #endif
1399
1400 /* journalling filesystem info */
1401 void *journal_info;
1402
1403 /* stacked block device info */
1404 struct bio_list *bio_list;
1405
1406 #ifdef CONFIG_BLOCK
1407 /* stack plugging */
1408 struct blk_plug *plug;
1409 #endif
1410
1411 /* VM state */
1412 struct reclaim_state *reclaim_state;
1413
1414 struct backing_dev_info *backing_dev_info;
1415
1416 struct io_context *io_context;
1417
1418 unsigned long ptrace_message;
1419 siginfo_t *last_siginfo; /* For ptrace use. */
1420 struct task_io_accounting ioac;
1421 #if defined(CONFIG_TASK_XACCT)
1422 u64 acct_rss_mem1; /* accumulated rss usage */
1423 u64 acct_vm_mem1; /* accumulated virtual memory usage */
1424 u64 acct_timexpd; /* stime + utime since last update */
1425 #endif
1426 #ifdef CONFIG_CPUSETS
1427 nodemask_t mems_allowed; /* Protected by alloc_lock */
1428 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */
1429 int cpuset_mem_spread_rotor;
1430 int cpuset_slab_spread_rotor;
1431 #endif
1432 #ifdef CONFIG_CGROUPS
1433 /* Control Group info protected by css_set_lock */
1434 struct css_set __rcu *cgroups;
1435 /* cg_list protected by css_set_lock and tsk->alloc_lock */
1436 struct list_head cg_list;
1437 #endif
1438 #ifdef CONFIG_INTEL_RDT_A
1439 int closid;
1440 #endif
1441 #ifdef CONFIG_FUTEX
1442 struct robust_list_head __user *robust_list;
1443 #ifdef CONFIG_COMPAT
1444 struct compat_robust_list_head __user *compat_robust_list;
1445 #endif
1446 struct list_head pi_state_list;
1447 struct futex_pi_state *pi_state_cache;
1448 #endif
1449 #ifdef CONFIG_PERF_EVENTS
1450 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1451 struct mutex perf_event_mutex;
1452 struct list_head perf_event_list;
1453 #endif
1454 #ifdef CONFIG_DEBUG_PREEMPT
1455 unsigned long preempt_disable_ip;
1456 #endif
1457 #ifdef CONFIG_NUMA
1458 struct mempolicy *mempolicy; /* Protected by alloc_lock */
1459 short il_next;
1460 short pref_node_fork;
1461 #endif
1462 #ifdef CONFIG_NUMA_BALANCING
1463 int numa_scan_seq;
1464 unsigned int numa_scan_period;
1465 unsigned int numa_scan_period_max;
1466 int numa_preferred_nid;
1467 unsigned long numa_migrate_retry;
1468 u64 node_stamp; /* migration stamp */
1469 u64 last_task_numa_placement;
1470 u64 last_sum_exec_runtime;
1471 struct callback_head numa_work;
1472
1473 struct list_head numa_entry;
1474 struct numa_group *numa_group;
1475
1476 /*
1477 * numa_faults is an array split into four regions:
1478 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1479 * in this precise order.
1480 *
1481 * faults_memory: Exponential decaying average of faults on a per-node
1482 * basis. Scheduling placement decisions are made based on these
1483 * counts. The values remain static for the duration of a PTE scan.
1484 * faults_cpu: Track the nodes the process was running on when a NUMA
1485 * hinting fault was incurred.
1486 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1487 * during the current scan window. When the scan completes, the counts
1488 * in faults_memory and faults_cpu decay and these values are copied.
1489 */
1490 unsigned long *numa_faults;
1491 unsigned long total_numa_faults;
1492
1493 /*
1494 * numa_faults_locality tracks if faults recorded during the last
1495 * scan window were remote/local or failed to migrate. The task scan
1496 * period is adapted based on the locality of the faults with different
1497 * weights depending on whether they were shared or private faults
1498 */
1499 unsigned long numa_faults_locality[3];
1500
1501 unsigned long numa_pages_migrated;
1502 #endif /* CONFIG_NUMA_BALANCING */
1503
1504 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
1505 struct tlbflush_unmap_batch tlb_ubc;
1506 #endif
1507
1508 struct rcu_head rcu;
1509
1510 /*
1511 * cache last used pipe for splice
1512 */
1513 struct pipe_inode_info *splice_pipe;
1514
1515 struct page_frag task_frag;
1516
1517 #ifdef CONFIG_TASK_DELAY_ACCT
1518 struct task_delay_info *delays;
1519 #endif
1520
1521 #ifdef CONFIG_FAULT_INJECTION
1522 int make_it_fail;
1523 #endif
1524 /*
1525 * when (nr_dirtied >= nr_dirtied_pause), it's time to call
1526 * balance_dirty_pages() for some dirty throttling pause
1527 */
1528 int nr_dirtied;
1529 int nr_dirtied_pause;
1530 unsigned long dirty_paused_when; /* start of a write-and-pause period */
1531
1532 #ifdef CONFIG_LATENCYTOP
1533 int latency_record_count;
1534 struct latency_record latency_record[LT_SAVECOUNT];
1535 #endif
1536 /*
1537 * time slack values; these are used to round up poll() and
1538 * select() etc timeout values. These are in nanoseconds.
1539 */
1540 u64 timer_slack_ns;
1541 u64 default_timer_slack_ns;
1542
1543 #ifdef CONFIG_KASAN
1544 unsigned int kasan_depth;
1545 #endif
1546 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1547 /* Index of current stored address in ret_stack */
1548 int curr_ret_stack;
1549 /* Stack of return addresses for return function tracing */
1550 struct ftrace_ret_stack *ret_stack;
1551 /* time stamp for last schedule */
1552 unsigned long long ftrace_timestamp;
1553 /*
1554 * Number of functions that haven't been traced
1555 * because of depth overrun.
1556 */
1557 atomic_t trace_overrun;
1558 /* Pause for the tracing */
1559 atomic_t tracing_graph_pause;
1560 #endif
1561 #ifdef CONFIG_TRACING
1562 /* state flags for use by tracers */
1563 unsigned long trace;
1564 /* bitmask and counter of trace recursion */
1565 unsigned long trace_recursion;
1566 #endif /* CONFIG_TRACING */
1567 #ifdef CONFIG_KCOV
1568 /* Coverage collection mode enabled for this task (0 if disabled). */
1569 enum kcov_mode kcov_mode;
1570 /* Size of the kcov_area. */
1571 unsigned kcov_size;
1572 /* Buffer for coverage collection. */
1573 void *kcov_area;
1574 /* kcov desciptor wired with this task or NULL. */
1575 struct kcov *kcov;
1576 #endif
1577 #ifdef CONFIG_MEMCG
1578 struct mem_cgroup *memcg_in_oom;
1579 gfp_t memcg_oom_gfp_mask;
1580 int memcg_oom_order;
1581
1582 /* number of pages to reclaim on returning to userland */
1583 unsigned int memcg_nr_pages_over_high;
1584 #endif
1585 #ifdef CONFIG_UPROBES
1586 struct uprobe_task *utask;
1587 #endif
1588 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1589 unsigned int sequential_io;
1590 unsigned int sequential_io_avg;
1591 #endif
1592 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1593 unsigned long task_state_change;
1594 #endif
1595 int pagefault_disabled;
1596 #ifdef CONFIG_MMU
1597 struct task_struct *oom_reaper_list;
1598 #endif
1599 #ifdef CONFIG_VMAP_STACK
1600 struct vm_struct *stack_vm_area;
1601 #endif
1602 #ifdef CONFIG_THREAD_INFO_IN_TASK
1603 /* A live task holds one reference. */
1604 atomic_t stack_refcount;
1605 #endif
1606 /* CPU-specific state of this task */
1607 struct thread_struct thread;
1608 /*
1609 * WARNING: on x86, 'thread_struct' contains a variable-sized
1610 * structure. It *MUST* be at the end of 'task_struct'.
1611 *
1612 * Do not put anything below here!
1613 */
1614 };
1615
1616 #ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT
1617 extern int arch_task_struct_size __read_mostly;
1618 #else
1619 # define arch_task_struct_size (sizeof(struct task_struct))
1620 #endif
1621
1622 #ifdef CONFIG_VMAP_STACK
1623 static inline struct vm_struct *task_stack_vm_area(const struct task_struct *t)
1624 {
1625 return t->stack_vm_area;
1626 }
1627 #else
1628 static inline struct vm_struct *task_stack_vm_area(const struct task_struct *t)
1629 {
1630 return NULL;
1631 }
1632 #endif
1633
1634 #define TNF_MIGRATED 0x01
1635 #define TNF_NO_GROUP 0x02
1636 #define TNF_SHARED 0x04
1637 #define TNF_FAULT_LOCAL 0x08
1638 #define TNF_MIGRATE_FAIL 0x10
1639
1640 static inline bool in_vfork(struct task_struct *tsk)
1641 {
1642 bool ret;
1643
1644 /*
1645 * need RCU to access ->real_parent if CLONE_VM was used along with
1646 * CLONE_PARENT.
1647 *
1648 * We check real_parent->mm == tsk->mm because CLONE_VFORK does not
1649 * imply CLONE_VM
1650 *
1651 * CLONE_VFORK can be used with CLONE_PARENT/CLONE_THREAD and thus
1652 * ->real_parent is not necessarily the task doing vfork(), so in
1653 * theory we can't rely on task_lock() if we want to dereference it.
1654 *
1655 * And in this case we can't trust the real_parent->mm == tsk->mm
1656 * check, it can be false negative. But we do not care, if init or
1657 * another oom-unkillable task does this it should blame itself.
1658 */
1659 rcu_read_lock();
1660 ret = tsk->vfork_done && tsk->real_parent->mm == tsk->mm;
1661 rcu_read_unlock();
1662
1663 return ret;
1664 }
1665
1666 #ifdef CONFIG_NUMA_BALANCING
1667 extern void task_numa_fault(int last_node, int node, int pages, int flags);
1668 extern pid_t task_numa_group_id(struct task_struct *p);
1669 extern void set_numabalancing_state(bool enabled);
1670 extern void task_numa_free(struct task_struct *p);
1671 extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page,
1672 int src_nid, int dst_cpu);
1673 #else
1674 static inline void task_numa_fault(int last_node, int node, int pages,
1675 int flags)
1676 {
1677 }
1678 static inline pid_t task_numa_group_id(struct task_struct *p)
1679 {
1680 return 0;
1681 }
1682 static inline void set_numabalancing_state(bool enabled)
1683 {
1684 }
1685 static inline void task_numa_free(struct task_struct *p)
1686 {
1687 }
1688 static inline bool should_numa_migrate_memory(struct task_struct *p,
1689 struct page *page, int src_nid, int dst_cpu)
1690 {
1691 return true;
1692 }
1693 #endif
1694
1695 static inline struct pid *task_pid(struct task_struct *task)
1696 {
1697 return task->pids[PIDTYPE_PID].pid;
1698 }
1699
1700 static inline struct pid *task_tgid(struct task_struct *task)
1701 {
1702 return task->group_leader->pids[PIDTYPE_PID].pid;
1703 }
1704
1705 /*
1706 * Without tasklist or rcu lock it is not safe to dereference
1707 * the result of task_pgrp/task_session even if task == current,
1708 * we can race with another thread doing sys_setsid/sys_setpgid.
1709 */
1710 static inline struct pid *task_pgrp(struct task_struct *task)
1711 {
1712 return task->group_leader->pids[PIDTYPE_PGID].pid;
1713 }
1714
1715 static inline struct pid *task_session(struct task_struct *task)
1716 {
1717 return task->group_leader->pids[PIDTYPE_SID].pid;
1718 }
1719
1720 struct pid_namespace;
1721
1722 /*
1723 * the helpers to get the task's different pids as they are seen
1724 * from various namespaces
1725 *
1726 * task_xid_nr() : global id, i.e. the id seen from the init namespace;
1727 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of
1728 * current.
1729 * task_xid_nr_ns() : id seen from the ns specified;
1730 *
1731 * set_task_vxid() : assigns a virtual id to a task;
1732 *
1733 * see also pid_nr() etc in include/linux/pid.h
1734 */
1735 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1736 struct pid_namespace *ns);
1737
1738 static inline pid_t task_pid_nr(struct task_struct *tsk)
1739 {
1740 return tsk->pid;
1741 }
1742
1743 static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1744 struct pid_namespace *ns)
1745 {
1746 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1747 }
1748
1749 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1750 {
1751 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1752 }
1753
1754
1755 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1756 {
1757 return tsk->tgid;
1758 }
1759
1760 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1761
1762 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1763 {
1764 return pid_vnr(task_tgid(tsk));
1765 }
1766
1767
1768 static inline int pid_alive(const struct task_struct *p);
1769 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1770 {
1771 pid_t pid = 0;
1772
1773 rcu_read_lock();
1774 if (pid_alive(tsk))
1775 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1776 rcu_read_unlock();
1777
1778 return pid;
1779 }
1780
1781 static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1782 {
1783 return task_ppid_nr_ns(tsk, &init_pid_ns);
1784 }
1785
1786 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1787 struct pid_namespace *ns)
1788 {
1789 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1790 }
1791
1792 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1793 {
1794 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1795 }
1796
1797
1798 static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1799 struct pid_namespace *ns)
1800 {
1801 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1802 }
1803
1804 static inline pid_t task_session_vnr(struct task_struct *tsk)
1805 {
1806 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1807 }
1808
1809 /* obsolete, do not use */
1810 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1811 {
1812 return task_pgrp_nr_ns(tsk, &init_pid_ns);
1813 }
1814
1815 /**
1816 * pid_alive - check that a task structure is not stale
1817 * @p: Task structure to be checked.
1818 *
1819 * Test if a process is not yet dead (at most zombie state)
1820 * If pid_alive fails, then pointers within the task structure
1821 * can be stale and must not be dereferenced.
1822 *
1823 * Return: 1 if the process is alive. 0 otherwise.
1824 */
1825 static inline int pid_alive(const struct task_struct *p)
1826 {
1827 return p->pids[PIDTYPE_PID].pid != NULL;
1828 }
1829
1830 /**
1831 * is_global_init - check if a task structure is init. Since init
1832 * is free to have sub-threads we need to check tgid.
1833 * @tsk: Task structure to be checked.
1834 *
1835 * Check if a task structure is the first user space task the kernel created.
1836 *
1837 * Return: 1 if the task structure is init. 0 otherwise.
1838 */
1839 static inline int is_global_init(struct task_struct *tsk)
1840 {
1841 return task_tgid_nr(tsk) == 1;
1842 }
1843
1844 extern struct pid *cad_pid;
1845
1846 extern void free_task(struct task_struct *tsk);
1847 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
1848
1849 extern void __put_task_struct(struct task_struct *t);
1850
1851 static inline void put_task_struct(struct task_struct *t)
1852 {
1853 if (atomic_dec_and_test(&t->usage))
1854 __put_task_struct(t);
1855 }
1856
1857 struct task_struct *task_rcu_dereference(struct task_struct **ptask);
1858 struct task_struct *try_get_task_struct(struct task_struct **ptask);
1859
1860 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1861 extern void task_cputime(struct task_struct *t,
1862 u64 *utime, u64 *stime);
1863 extern u64 task_gtime(struct task_struct *t);
1864 #else
1865 static inline void task_cputime(struct task_struct *t,
1866 u64 *utime, u64 *stime)
1867 {
1868 *utime = t->utime;
1869 *stime = t->stime;
1870 }
1871
1872 static inline u64 task_gtime(struct task_struct *t)
1873 {
1874 return t->gtime;
1875 }
1876 #endif
1877
1878 #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME
1879 static inline void task_cputime_scaled(struct task_struct *t,
1880 u64 *utimescaled,
1881 u64 *stimescaled)
1882 {
1883 *utimescaled = t->utimescaled;
1884 *stimescaled = t->stimescaled;
1885 }
1886 #else
1887 static inline void task_cputime_scaled(struct task_struct *t,
1888 u64 *utimescaled,
1889 u64 *stimescaled)
1890 {
1891 task_cputime(t, utimescaled, stimescaled);
1892 }
1893 #endif
1894
1895 extern void task_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st);
1896 extern void thread_group_cputime_adjusted(struct task_struct *p, u64 *ut, u64 *st);
1897
1898 /*
1899 * Per process flags
1900 */
1901 #define PF_IDLE 0x00000002 /* I am an IDLE thread */
1902 #define PF_EXITING 0x00000004 /* getting shut down */
1903 #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */
1904 #define PF_VCPU 0x00000010 /* I'm a virtual CPU */
1905 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */
1906 #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
1907 #define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */
1908 #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
1909 #define PF_DUMPCORE 0x00000200 /* dumped core */
1910 #define PF_SIGNALED 0x00000400 /* killed by a signal */
1911 #define PF_MEMALLOC 0x00000800 /* Allocating memory */
1912 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */
1913 #define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
1914 #define PF_USED_ASYNC 0x00004000 /* used async_schedule*(), used by module init */
1915 #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
1916 #define PF_FROZEN 0x00010000 /* frozen for system suspend */
1917 #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
1918 #define PF_KSWAPD 0x00040000 /* I am kswapd */
1919 #define PF_MEMALLOC_NOIO 0x00080000 /* Allocating memory without IO involved */
1920 #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
1921 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */
1922 #define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */
1923 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
1924 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */
1925 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
1926 #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
1927 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */
1928 #define PF_SUSPEND_TASK 0x80000000 /* this thread called freeze_processes and should not be frozen */
1929
1930 /*
1931 * Only the _current_ task can read/write to tsk->flags, but other
1932 * tasks can access tsk->flags in readonly mode for example
1933 * with tsk_used_math (like during threaded core dumping).
1934 * There is however an exception to this rule during ptrace
1935 * or during fork: the ptracer task is allowed to write to the
1936 * child->flags of its traced child (same goes for fork, the parent
1937 * can write to the child->flags), because we're guaranteed the
1938 * child is not running and in turn not changing child->flags
1939 * at the same time the parent does it.
1940 */
1941 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
1942 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
1943 #define clear_used_math() clear_stopped_child_used_math(current)
1944 #define set_used_math() set_stopped_child_used_math(current)
1945 #define conditional_stopped_child_used_math(condition, child) \
1946 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
1947 #define conditional_used_math(condition) \
1948 conditional_stopped_child_used_math(condition, current)
1949 #define copy_to_stopped_child_used_math(child) \
1950 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
1951 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
1952 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
1953 #define used_math() tsk_used_math(current)
1954
1955 /* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags
1956 * __GFP_FS is also cleared as it implies __GFP_IO.
1957 */
1958 static inline gfp_t memalloc_noio_flags(gfp_t flags)
1959 {
1960 if (unlikely(current->flags & PF_MEMALLOC_NOIO))
1961 flags &= ~(__GFP_IO | __GFP_FS);
1962 return flags;
1963 }
1964
1965 static inline unsigned int memalloc_noio_save(void)
1966 {
1967 unsigned int flags = current->flags & PF_MEMALLOC_NOIO;
1968 current->flags |= PF_MEMALLOC_NOIO;
1969 return flags;
1970 }
1971
1972 static inline void memalloc_noio_restore(unsigned int flags)
1973 {
1974 current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags;
1975 }
1976
1977 /* Per-process atomic flags. */
1978 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */
1979 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */
1980 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */
1981 #define PFA_LMK_WAITING 3 /* Lowmemorykiller is waiting */
1982
1983
1984 #define TASK_PFA_TEST(name, func) \
1985 static inline bool task_##func(struct task_struct *p) \
1986 { return test_bit(PFA_##name, &p->atomic_flags); }
1987 #define TASK_PFA_SET(name, func) \
1988 static inline void task_set_##func(struct task_struct *p) \
1989 { set_bit(PFA_##name, &p->atomic_flags); }
1990 #define TASK_PFA_CLEAR(name, func) \
1991 static inline void task_clear_##func(struct task_struct *p) \
1992 { clear_bit(PFA_##name, &p->atomic_flags); }
1993
1994 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
1995 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
1996
1997 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
1998 TASK_PFA_SET(SPREAD_PAGE, spread_page)
1999 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
2000
2001 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
2002 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
2003 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
2004
2005 TASK_PFA_TEST(LMK_WAITING, lmk_waiting)
2006 TASK_PFA_SET(LMK_WAITING, lmk_waiting)
2007
2008 /*
2009 * task->jobctl flags
2010 */
2011 #define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */
2012
2013 #define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */
2014 #define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */
2015 #define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */
2016 #define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */
2017 #define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */
2018 #define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */
2019 #define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */
2020
2021 #define JOBCTL_STOP_DEQUEUED (1UL << JOBCTL_STOP_DEQUEUED_BIT)
2022 #define JOBCTL_STOP_PENDING (1UL << JOBCTL_STOP_PENDING_BIT)
2023 #define JOBCTL_STOP_CONSUME (1UL << JOBCTL_STOP_CONSUME_BIT)
2024 #define JOBCTL_TRAP_STOP (1UL << JOBCTL_TRAP_STOP_BIT)
2025 #define JOBCTL_TRAP_NOTIFY (1UL << JOBCTL_TRAP_NOTIFY_BIT)
2026 #define JOBCTL_TRAPPING (1UL << JOBCTL_TRAPPING_BIT)
2027 #define JOBCTL_LISTENING (1UL << JOBCTL_LISTENING_BIT)
2028
2029 #define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY)
2030 #define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK)
2031
2032 extern bool task_set_jobctl_pending(struct task_struct *task,
2033 unsigned long mask);
2034 extern void task_clear_jobctl_trapping(struct task_struct *task);
2035 extern void task_clear_jobctl_pending(struct task_struct *task,
2036 unsigned long mask);
2037
2038 static inline void rcu_copy_process(struct task_struct *p)
2039 {
2040 #ifdef CONFIG_PREEMPT_RCU
2041 p->rcu_read_lock_nesting = 0;
2042 p->rcu_read_unlock_special.s = 0;
2043 p->rcu_blocked_node = NULL;
2044 INIT_LIST_HEAD(&p->rcu_node_entry);
2045 #endif /* #ifdef CONFIG_PREEMPT_RCU */
2046 #ifdef CONFIG_TASKS_RCU
2047 p->rcu_tasks_holdout = false;
2048 INIT_LIST_HEAD(&p->rcu_tasks_holdout_list);
2049 p->rcu_tasks_idle_cpu = -1;
2050 #endif /* #ifdef CONFIG_TASKS_RCU */
2051 }
2052
2053 static inline void tsk_restore_flags(struct task_struct *task,
2054 unsigned long orig_flags, unsigned long flags)
2055 {
2056 task->flags &= ~flags;
2057 task->flags |= orig_flags & flags;
2058 }
2059
2060 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur,
2061 const struct cpumask *trial);
2062 extern int task_can_attach(struct task_struct *p,
2063 const struct cpumask *cs_cpus_allowed);
2064 #ifdef CONFIG_SMP
2065 extern void do_set_cpus_allowed(struct task_struct *p,
2066 const struct cpumask *new_mask);
2067
2068 extern int set_cpus_allowed_ptr(struct task_struct *p,
2069 const struct cpumask *new_mask);
2070 #else
2071 static inline void do_set_cpus_allowed(struct task_struct *p,
2072 const struct cpumask *new_mask)
2073 {
2074 }
2075 static inline int set_cpus_allowed_ptr(struct task_struct *p,
2076 const struct cpumask *new_mask)
2077 {
2078 if (!cpumask_test_cpu(0, new_mask))
2079 return -EINVAL;
2080 return 0;
2081 }
2082 #endif
2083
2084 #ifdef CONFIG_NO_HZ_COMMON
2085 void calc_load_enter_idle(void);
2086 void calc_load_exit_idle(void);
2087 #else
2088 static inline void calc_load_enter_idle(void) { }
2089 static inline void calc_load_exit_idle(void) { }
2090 #endif /* CONFIG_NO_HZ_COMMON */
2091
2092 #ifndef cpu_relax_yield
2093 #define cpu_relax_yield() cpu_relax()
2094 #endif
2095
2096 extern unsigned long long
2097 task_sched_runtime(struct task_struct *task);
2098
2099 /* sched_exec is called by processes performing an exec */
2100 #ifdef CONFIG_SMP
2101 extern void sched_exec(void);
2102 #else
2103 #define sched_exec() {}
2104 #endif
2105
2106 #ifdef CONFIG_HOTPLUG_CPU
2107 extern void idle_task_exit(void);
2108 #else
2109 static inline void idle_task_exit(void) {}
2110 #endif
2111
2112 #if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
2113 extern void wake_up_nohz_cpu(int cpu);
2114 #else
2115 static inline void wake_up_nohz_cpu(int cpu) { }
2116 #endif
2117
2118 #ifdef CONFIG_NO_HZ_FULL
2119 extern u64 scheduler_tick_max_deferment(void);
2120 #endif
2121
2122 #ifdef CONFIG_SCHED_AUTOGROUP
2123 extern void sched_autogroup_create_attach(struct task_struct *p);
2124 extern void sched_autogroup_detach(struct task_struct *p);
2125 extern void sched_autogroup_fork(struct signal_struct *sig);
2126 extern void sched_autogroup_exit(struct signal_struct *sig);
2127 extern void sched_autogroup_exit_task(struct task_struct *p);
2128 #ifdef CONFIG_PROC_FS
2129 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
2130 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice);
2131 #endif
2132 #else
2133 static inline void sched_autogroup_create_attach(struct task_struct *p) { }
2134 static inline void sched_autogroup_detach(struct task_struct *p) { }
2135 static inline void sched_autogroup_fork(struct signal_struct *sig) { }
2136 static inline void sched_autogroup_exit(struct signal_struct *sig) { }
2137 static inline void sched_autogroup_exit_task(struct task_struct *p) { }
2138 #endif
2139
2140 extern int yield_to(struct task_struct *p, bool preempt);
2141 extern void set_user_nice(struct task_struct *p, long nice);
2142 extern int task_prio(const struct task_struct *p);
2143 /**
2144 * task_nice - return the nice value of a given task.
2145 * @p: the task in question.
2146 *
2147 * Return: The nice value [ -20 ... 0 ... 19 ].
2148 */
2149 static inline int task_nice(const struct task_struct *p)
2150 {
2151 return PRIO_TO_NICE((p)->static_prio);
2152 }
2153 extern int can_nice(const struct task_struct *p, const int nice);
2154 extern int task_curr(const struct task_struct *p);
2155 extern int idle_cpu(int cpu);
2156 extern int sched_setscheduler(struct task_struct *, int,
2157 const struct sched_param *);
2158 extern int sched_setscheduler_nocheck(struct task_struct *, int,
2159 const struct sched_param *);
2160 extern int sched_setattr(struct task_struct *,
2161 const struct sched_attr *);
2162 extern struct task_struct *idle_task(int cpu);
2163 /**
2164 * is_idle_task - is the specified task an idle task?
2165 * @p: the task in question.
2166 *
2167 * Return: 1 if @p is an idle task. 0 otherwise.
2168 */
2169 static inline bool is_idle_task(const struct task_struct *p)
2170 {
2171 return !!(p->flags & PF_IDLE);
2172 }
2173 extern struct task_struct *curr_task(int cpu);
2174 extern void ia64_set_curr_task(int cpu, struct task_struct *p);
2175
2176 void yield(void);
2177
2178 union thread_union {
2179 #ifndef CONFIG_THREAD_INFO_IN_TASK
2180 struct thread_info thread_info;
2181 #endif
2182 unsigned long stack[THREAD_SIZE/sizeof(long)];
2183 };
2184
2185 #ifndef __HAVE_ARCH_KSTACK_END
2186 static inline int kstack_end(void *addr)
2187 {
2188 /* Reliable end of stack detection:
2189 * Some APM bios versions misalign the stack
2190 */
2191 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
2192 }
2193 #endif
2194
2195 extern union thread_union init_thread_union;
2196 extern struct task_struct init_task;
2197
2198 extern struct mm_struct init_mm;
2199
2200 extern struct pid_namespace init_pid_ns;
2201
2202 /*
2203 * find a task by one of its numerical ids
2204 *
2205 * find_task_by_pid_ns():
2206 * finds a task by its pid in the specified namespace
2207 * find_task_by_vpid():
2208 * finds a task by its virtual pid
2209 *
2210 * see also find_vpid() etc in include/linux/pid.h
2211 */
2212
2213 extern struct task_struct *find_task_by_vpid(pid_t nr);
2214 extern struct task_struct *find_task_by_pid_ns(pid_t nr,
2215 struct pid_namespace *ns);
2216
2217 /* per-UID process charging. */
2218 extern struct user_struct * alloc_uid(kuid_t);
2219 static inline struct user_struct *get_uid(struct user_struct *u)
2220 {
2221 atomic_inc(&u->__count);
2222 return u;
2223 }
2224 extern void free_uid(struct user_struct *);
2225
2226 #include <asm/current.h>
2227
2228 extern void xtime_update(unsigned long ticks);
2229
2230 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2231 extern int wake_up_process(struct task_struct *tsk);
2232 extern void wake_up_new_task(struct task_struct *tsk);
2233 #ifdef CONFIG_SMP
2234 extern void kick_process(struct task_struct *tsk);
2235 #else
2236 static inline void kick_process(struct task_struct *tsk) { }
2237 #endif
2238 extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
2239 extern void sched_dead(struct task_struct *p);
2240
2241 extern void proc_caches_init(void);
2242 extern void flush_signals(struct task_struct *);
2243 extern void ignore_signals(struct task_struct *);
2244 extern void flush_signal_handlers(struct task_struct *, int force_default);
2245 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2246
2247 static inline int kernel_dequeue_signal(siginfo_t *info)
2248 {
2249 struct task_struct *tsk = current;
2250 siginfo_t __info;
2251 int ret;
2252
2253 spin_lock_irq(&tsk->sighand->siglock);
2254 ret = dequeue_signal(tsk, &tsk->blocked, info ?: &__info);
2255 spin_unlock_irq(&tsk->sighand->siglock);
2256
2257 return ret;
2258 }
2259
2260 static inline void kernel_signal_stop(void)
2261 {
2262 spin_lock_irq(&current->sighand->siglock);
2263 if (current->jobctl & JOBCTL_STOP_DEQUEUED)
2264 __set_current_state(TASK_STOPPED);
2265 spin_unlock_irq(&current->sighand->siglock);
2266
2267 schedule();
2268 }
2269
2270 extern void release_task(struct task_struct * p);
2271 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2272 extern int force_sigsegv(int, struct task_struct *);
2273 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2274 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2275 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2276 extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *,
2277 const struct cred *, u32);
2278 extern int kill_pgrp(struct pid *pid, int sig, int priv);
2279 extern int kill_pid(struct pid *pid, int sig, int priv);
2280 extern int kill_proc_info(int, struct siginfo *, pid_t);
2281 extern __must_check bool do_notify_parent(struct task_struct *, int);
2282 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2283 extern void force_sig(int, struct task_struct *);
2284 extern int send_sig(int, struct task_struct *, int);
2285 extern int zap_other_threads(struct task_struct *p);
2286 extern struct sigqueue *sigqueue_alloc(void);
2287 extern void sigqueue_free(struct sigqueue *);
2288 extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group);
2289 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2290
2291 #ifdef TIF_RESTORE_SIGMASK
2292 /*
2293 * Legacy restore_sigmask accessors. These are inefficient on
2294 * SMP architectures because they require atomic operations.
2295 */
2296
2297 /**
2298 * set_restore_sigmask() - make sure saved_sigmask processing gets done
2299 *
2300 * This sets TIF_RESTORE_SIGMASK and ensures that the arch signal code
2301 * will run before returning to user mode, to process the flag. For
2302 * all callers, TIF_SIGPENDING is already set or it's no harm to set
2303 * it. TIF_RESTORE_SIGMASK need not be in the set of bits that the
2304 * arch code will notice on return to user mode, in case those bits
2305 * are scarce. We set TIF_SIGPENDING here to ensure that the arch
2306 * signal code always gets run when TIF_RESTORE_SIGMASK is set.
2307 */
2308 static inline void set_restore_sigmask(void)
2309 {
2310 set_thread_flag(TIF_RESTORE_SIGMASK);
2311 WARN_ON(!test_thread_flag(TIF_SIGPENDING));
2312 }
2313 static inline void clear_restore_sigmask(void)
2314 {
2315 clear_thread_flag(TIF_RESTORE_SIGMASK);
2316 }
2317 static inline bool test_restore_sigmask(void)
2318 {
2319 return test_thread_flag(TIF_RESTORE_SIGMASK);
2320 }
2321 static inline bool test_and_clear_restore_sigmask(void)
2322 {
2323 return test_and_clear_thread_flag(TIF_RESTORE_SIGMASK);
2324 }
2325
2326 #else /* TIF_RESTORE_SIGMASK */
2327
2328 /* Higher-quality implementation, used if TIF_RESTORE_SIGMASK doesn't exist. */
2329 static inline void set_restore_sigmask(void)
2330 {
2331 current->restore_sigmask = true;
2332 WARN_ON(!test_thread_flag(TIF_SIGPENDING));
2333 }
2334 static inline void clear_restore_sigmask(void)
2335 {
2336 current->restore_sigmask = false;
2337 }
2338 static inline bool test_restore_sigmask(void)
2339 {
2340 return current->restore_sigmask;
2341 }
2342 static inline bool test_and_clear_restore_sigmask(void)
2343 {
2344 if (!current->restore_sigmask)
2345 return false;
2346 current->restore_sigmask = false;
2347 return true;
2348 }
2349 #endif
2350
2351 static inline void restore_saved_sigmask(void)
2352 {
2353 if (test_and_clear_restore_sigmask())
2354 __set_current_blocked(&current->saved_sigmask);
2355 }
2356
2357 static inline sigset_t *sigmask_to_save(void)
2358 {
2359 sigset_t *res = &current->blocked;
2360 if (unlikely(test_restore_sigmask()))
2361 res = &current->saved_sigmask;
2362 return res;
2363 }
2364
2365 static inline int kill_cad_pid(int sig, int priv)
2366 {
2367 return kill_pid(cad_pid, sig, priv);
2368 }
2369
2370 /* These can be the second arg to send_sig_info/send_group_sig_info. */
2371 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
2372 #define SEND_SIG_PRIV ((struct siginfo *) 1)
2373 #define SEND_SIG_FORCED ((struct siginfo *) 2)
2374
2375 /*
2376 * True if we are on the alternate signal stack.
2377 */
2378 static inline int on_sig_stack(unsigned long sp)
2379 {
2380 /*
2381 * If the signal stack is SS_AUTODISARM then, by construction, we
2382 * can't be on the signal stack unless user code deliberately set
2383 * SS_AUTODISARM when we were already on it.
2384 *
2385 * This improves reliability: if user state gets corrupted such that
2386 * the stack pointer points very close to the end of the signal stack,
2387 * then this check will enable the signal to be handled anyway.
2388 */
2389 if (current->sas_ss_flags & SS_AUTODISARM)
2390 return 0;
2391
2392 #ifdef CONFIG_STACK_GROWSUP
2393 return sp >= current->sas_ss_sp &&
2394 sp - current->sas_ss_sp < current->sas_ss_size;
2395 #else
2396 return sp > current->sas_ss_sp &&
2397 sp - current->sas_ss_sp <= current->sas_ss_size;
2398 #endif
2399 }
2400
2401 static inline int sas_ss_flags(unsigned long sp)
2402 {
2403 if (!current->sas_ss_size)
2404 return SS_DISABLE;
2405
2406 return on_sig_stack(sp) ? SS_ONSTACK : 0;
2407 }
2408
2409 static inline void sas_ss_reset(struct task_struct *p)
2410 {
2411 p->sas_ss_sp = 0;
2412 p->sas_ss_size = 0;
2413 p->sas_ss_flags = SS_DISABLE;
2414 }
2415
2416 static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig)
2417 {
2418 if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp))
2419 #ifdef CONFIG_STACK_GROWSUP
2420 return current->sas_ss_sp;
2421 #else
2422 return current->sas_ss_sp + current->sas_ss_size;
2423 #endif
2424 return sp;
2425 }
2426
2427 /*
2428 * Routines for handling mm_structs
2429 */
2430 extern struct mm_struct * mm_alloc(void);
2431
2432 /**
2433 * mmgrab() - Pin a &struct mm_struct.
2434 * @mm: The &struct mm_struct to pin.
2435 *
2436 * Make sure that @mm will not get freed even after the owning task
2437 * exits. This doesn't guarantee that the associated address space
2438 * will still exist later on and mmget_not_zero() has to be used before
2439 * accessing it.
2440 *
2441 * This is a preferred way to to pin @mm for a longer/unbounded amount
2442 * of time.
2443 *
2444 * Use mmdrop() to release the reference acquired by mmgrab().
2445 *
2446 * See also <Documentation/vm/active_mm.txt> for an in-depth explanation
2447 * of &mm_struct.mm_count vs &mm_struct.mm_users.
2448 */
2449 static inline void mmgrab(struct mm_struct *mm)
2450 {
2451 atomic_inc(&mm->mm_count);
2452 }
2453
2454 /* mmdrop drops the mm and the page tables */
2455 extern void __mmdrop(struct mm_struct *);
2456 static inline void mmdrop(struct mm_struct *mm)
2457 {
2458 if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2459 __mmdrop(mm);
2460 }
2461
2462 static inline void mmdrop_async_fn(struct work_struct *work)
2463 {
2464 struct mm_struct *mm = container_of(work, struct mm_struct, async_put_work);
2465 __mmdrop(mm);
2466 }
2467
2468 static inline void mmdrop_async(struct mm_struct *mm)
2469 {
2470 if (unlikely(atomic_dec_and_test(&mm->mm_count))) {
2471 INIT_WORK(&mm->async_put_work, mmdrop_async_fn);
2472 schedule_work(&mm->async_put_work);
2473 }
2474 }
2475
2476 /**
2477 * mmget() - Pin the address space associated with a &struct mm_struct.
2478 * @mm: The address space to pin.
2479 *
2480 * Make sure that the address space of the given &struct mm_struct doesn't
2481 * go away. This does not protect against parts of the address space being
2482 * modified or freed, however.
2483 *
2484 * Never use this function to pin this address space for an
2485 * unbounded/indefinite amount of time.
2486 *
2487 * Use mmput() to release the reference acquired by mmget().
2488 *
2489 * See also <Documentation/vm/active_mm.txt> for an in-depth explanation
2490 * of &mm_struct.mm_count vs &mm_struct.mm_users.
2491 */
2492 static inline void mmget(struct mm_struct *mm)
2493 {
2494 atomic_inc(&mm->mm_users);
2495 }
2496
2497 static inline bool mmget_not_zero(struct mm_struct *mm)
2498 {
2499 return atomic_inc_not_zero(&mm->mm_users);
2500 }
2501
2502 /* mmput gets rid of the mappings and all user-space */
2503 extern void mmput(struct mm_struct *);
2504 #ifdef CONFIG_MMU
2505 /* same as above but performs the slow path from the async context. Can
2506 * be called from the atomic context as well
2507 */
2508 extern void mmput_async(struct mm_struct *);
2509 #endif
2510
2511 /* Grab a reference to a task's mm, if it is not already going away */
2512 extern struct mm_struct *get_task_mm(struct task_struct *task);
2513 /*
2514 * Grab a reference to a task's mm, if it is not already going away
2515 * and ptrace_may_access with the mode parameter passed to it
2516 * succeeds.
2517 */
2518 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode);
2519 /* Remove the current tasks stale references to the old mm_struct */
2520 extern void mm_release(struct task_struct *, struct mm_struct *);
2521
2522 #ifdef CONFIG_HAVE_COPY_THREAD_TLS
2523 extern int copy_thread_tls(unsigned long, unsigned long, unsigned long,
2524 struct task_struct *, unsigned long);
2525 #else
2526 extern int copy_thread(unsigned long, unsigned long, unsigned long,
2527 struct task_struct *);
2528
2529 /* Architectures that haven't opted into copy_thread_tls get the tls argument
2530 * via pt_regs, so ignore the tls argument passed via C. */
2531 static inline int copy_thread_tls(
2532 unsigned long clone_flags, unsigned long sp, unsigned long arg,
2533 struct task_struct *p, unsigned long tls)
2534 {
2535 return copy_thread(clone_flags, sp, arg, p);
2536 }
2537 #endif
2538 extern void flush_thread(void);
2539
2540 #ifdef CONFIG_HAVE_EXIT_THREAD
2541 extern void exit_thread(struct task_struct *tsk);
2542 #else
2543 static inline void exit_thread(struct task_struct *tsk)
2544 {
2545 }
2546 #endif
2547
2548 extern void exit_files(struct task_struct *);
2549 extern void __cleanup_sighand(struct sighand_struct *);
2550
2551 extern void exit_itimers(struct signal_struct *);
2552 extern void flush_itimer_signals(void);
2553
2554 extern void do_group_exit(int);
2555
2556 extern int do_execve(struct filename *,
2557 const char __user * const __user *,
2558 const char __user * const __user *);
2559 extern int do_execveat(int, struct filename *,
2560 const char __user * const __user *,
2561 const char __user * const __user *,
2562 int);
2563 extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long);
2564 extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
2565 struct task_struct *fork_idle(int);
2566 extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
2567
2568 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
2569 static inline void set_task_comm(struct task_struct *tsk, const char *from)
2570 {
2571 __set_task_comm(tsk, from, false);
2572 }
2573 extern char *get_task_comm(char *to, struct task_struct *tsk);
2574
2575 #ifdef CONFIG_SMP
2576 void scheduler_ipi(void);
2577 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2578 #else
2579 static inline void scheduler_ipi(void) { }
2580 static inline unsigned long wait_task_inactive(struct task_struct *p,
2581 long match_state)
2582 {
2583 return 1;
2584 }
2585 #endif
2586
2587 #define tasklist_empty() \
2588 list_empty(&init_task.tasks)
2589
2590 #define next_task(p) \
2591 list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2592
2593 #define for_each_process(p) \
2594 for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2595
2596 extern bool current_is_single_threaded(void);
2597
2598 /*
2599 * Careful: do_each_thread/while_each_thread is a double loop so
2600 * 'break' will not work as expected - use goto instead.
2601 */
2602 #define do_each_thread(g, t) \
2603 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2604
2605 #define while_each_thread(g, t) \
2606 while ((t = next_thread(t)) != g)
2607
2608 #define __for_each_thread(signal, t) \
2609 list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node)
2610
2611 #define for_each_thread(p, t) \
2612 __for_each_thread((p)->signal, t)
2613
2614 /* Careful: this is a double loop, 'break' won't work as expected. */
2615 #define for_each_process_thread(p, t) \
2616 for_each_process(p) for_each_thread(p, t)
2617
2618 typedef int (*proc_visitor)(struct task_struct *p, void *data);
2619 void walk_process_tree(struct task_struct *top, proc_visitor, void *);
2620
2621 static inline int get_nr_threads(struct task_struct *tsk)
2622 {
2623 return tsk->signal->nr_threads;
2624 }
2625
2626 static inline bool thread_group_leader(struct task_struct *p)
2627 {
2628 return p->exit_signal >= 0;
2629 }
2630
2631 /* Do to the insanities of de_thread it is possible for a process
2632 * to have the pid of the thread group leader without actually being
2633 * the thread group leader. For iteration through the pids in proc
2634 * all we care about is that we have a task with the appropriate
2635 * pid, we don't actually care if we have the right task.
2636 */
2637 static inline bool has_group_leader_pid(struct task_struct *p)
2638 {
2639 return task_pid(p) == p->signal->leader_pid;
2640 }
2641
2642 static inline
2643 bool same_thread_group(struct task_struct *p1, struct task_struct *p2)
2644 {
2645 return p1->signal == p2->signal;
2646 }
2647
2648 static inline struct task_struct *next_thread(const struct task_struct *p)
2649 {
2650 return list_entry_rcu(p->thread_group.next,
2651 struct task_struct, thread_group);
2652 }
2653
2654 static inline int thread_group_empty(struct task_struct *p)
2655 {
2656 return list_empty(&p->thread_group);
2657 }
2658
2659 #define delay_group_leader(p) \
2660 (thread_group_leader(p) && !thread_group_empty(p))
2661
2662 /*
2663 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2664 * subscriptions and synchronises with wait4(). Also used in procfs. Also
2665 * pins the final release of task.io_context. Also protects ->cpuset and
2666 * ->cgroup.subsys[]. And ->vfork_done.
2667 *
2668 * Nests both inside and outside of read_lock(&tasklist_lock).
2669 * It must not be nested with write_lock_irq(&tasklist_lock),
2670 * neither inside nor outside.
2671 */
2672 static inline void task_lock(struct task_struct *p)
2673 {
2674 spin_lock(&p->alloc_lock);
2675 }
2676
2677 static inline void task_unlock(struct task_struct *p)
2678 {
2679 spin_unlock(&p->alloc_lock);
2680 }
2681
2682 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2683 unsigned long *flags);
2684
2685 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2686 unsigned long *flags)
2687 {
2688 struct sighand_struct *ret;
2689
2690 ret = __lock_task_sighand(tsk, flags);
2691 (void)__cond_lock(&tsk->sighand->siglock, ret);
2692 return ret;
2693 }
2694
2695 static inline void unlock_task_sighand(struct task_struct *tsk,
2696 unsigned long *flags)
2697 {
2698 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2699 }
2700
2701 #ifdef CONFIG_THREAD_INFO_IN_TASK
2702
2703 static inline struct thread_info *task_thread_info(struct task_struct *task)
2704 {
2705 return &task->thread_info;
2706 }
2707
2708 /*
2709 * When accessing the stack of a non-current task that might exit, use
2710 * try_get_task_stack() instead. task_stack_page will return a pointer
2711 * that could get freed out from under you.
2712 */
2713 static inline void *task_stack_page(const struct task_struct *task)
2714 {
2715 return task->stack;
2716 }
2717
2718 #define setup_thread_stack(new,old) do { } while(0)
2719
2720 static inline unsigned long *end_of_stack(const struct task_struct *task)
2721 {
2722 return task->stack;
2723 }
2724
2725 #elif !defined(__HAVE_THREAD_FUNCTIONS)
2726
2727 #define task_thread_info(task) ((struct thread_info *)(task)->stack)
2728 #define task_stack_page(task) ((void *)(task)->stack)
2729
2730 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2731 {
2732 *task_thread_info(p) = *task_thread_info(org);
2733 task_thread_info(p)->task = p;
2734 }
2735
2736 /*
2737 * Return the address of the last usable long on the stack.
2738 *
2739 * When the stack grows down, this is just above the thread
2740 * info struct. Going any lower will corrupt the threadinfo.
2741 *
2742 * When the stack grows up, this is the highest address.
2743 * Beyond that position, we corrupt data on the next page.
2744 */
2745 static inline unsigned long *end_of_stack(struct task_struct *p)
2746 {
2747 #ifdef CONFIG_STACK_GROWSUP
2748 return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1;
2749 #else
2750 return (unsigned long *)(task_thread_info(p) + 1);
2751 #endif
2752 }
2753
2754 #endif
2755
2756 #ifdef CONFIG_THREAD_INFO_IN_TASK
2757 static inline void *try_get_task_stack(struct task_struct *tsk)
2758 {
2759 return atomic_inc_not_zero(&tsk->stack_refcount) ?
2760 task_stack_page(tsk) : NULL;
2761 }
2762
2763 extern void put_task_stack(struct task_struct *tsk);
2764 #else
2765 static inline void *try_get_task_stack(struct task_struct *tsk)
2766 {
2767 return task_stack_page(tsk);
2768 }
2769
2770 static inline void put_task_stack(struct task_struct *tsk) {}
2771 #endif
2772
2773 #define task_stack_end_corrupted(task) \
2774 (*(end_of_stack(task)) != STACK_END_MAGIC)
2775
2776 static inline int object_is_on_stack(void *obj)
2777 {
2778 void *stack = task_stack_page(current);
2779
2780 return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2781 }
2782
2783 extern void thread_stack_cache_init(void);
2784
2785 #ifdef CONFIG_DEBUG_STACK_USAGE
2786 static inline unsigned long stack_not_used(struct task_struct *p)
2787 {
2788 unsigned long *n = end_of_stack(p);
2789
2790 do { /* Skip over canary */
2791 # ifdef CONFIG_STACK_GROWSUP
2792 n--;
2793 # else
2794 n++;
2795 # endif
2796 } while (!*n);
2797
2798 # ifdef CONFIG_STACK_GROWSUP
2799 return (unsigned long)end_of_stack(p) - (unsigned long)n;
2800 # else
2801 return (unsigned long)n - (unsigned long)end_of_stack(p);
2802 # endif
2803 }
2804 #endif
2805 extern void set_task_stack_end_magic(struct task_struct *tsk);
2806
2807 /* set thread flags in other task's structures
2808 * - see asm/thread_info.h for TIF_xxxx flags available
2809 */
2810 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2811 {
2812 set_ti_thread_flag(task_thread_info(tsk), flag);
2813 }
2814
2815 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2816 {
2817 clear_ti_thread_flag(task_thread_info(tsk), flag);
2818 }
2819
2820 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2821 {
2822 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2823 }
2824
2825 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2826 {
2827 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2828 }
2829
2830 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2831 {
2832 return test_ti_thread_flag(task_thread_info(tsk), flag);
2833 }
2834
2835 static inline void set_tsk_need_resched(struct task_struct *tsk)
2836 {
2837 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2838 }
2839
2840 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2841 {
2842 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2843 }
2844
2845 static inline int test_tsk_need_resched(struct task_struct *tsk)
2846 {
2847 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2848 }
2849
2850 static inline int restart_syscall(void)
2851 {
2852 set_tsk_thread_flag(current, TIF_SIGPENDING);
2853 return -ERESTARTNOINTR;
2854 }
2855
2856 static inline int signal_pending(struct task_struct *p)
2857 {
2858 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2859 }
2860
2861 static inline int __fatal_signal_pending(struct task_struct *p)
2862 {
2863 return unlikely(sigismember(&p->pending.signal, SIGKILL));
2864 }
2865
2866 static inline int fatal_signal_pending(struct task_struct *p)
2867 {
2868 return signal_pending(p) && __fatal_signal_pending(p);
2869 }
2870
2871 static inline int signal_pending_state(long state, struct task_struct *p)
2872 {
2873 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2874 return 0;
2875 if (!signal_pending(p))
2876 return 0;
2877
2878 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2879 }
2880
2881 /*
2882 * cond_resched() and cond_resched_lock(): latency reduction via
2883 * explicit rescheduling in places that are safe. The return
2884 * value indicates whether a reschedule was done in fact.
2885 * cond_resched_lock() will drop the spinlock before scheduling,
2886 * cond_resched_softirq() will enable bhs before scheduling.
2887 */
2888 #ifndef CONFIG_PREEMPT
2889 extern int _cond_resched(void);
2890 #else
2891 static inline int _cond_resched(void) { return 0; }
2892 #endif
2893
2894 #define cond_resched() ({ \
2895 ___might_sleep(__FILE__, __LINE__, 0); \
2896 _cond_resched(); \
2897 })
2898
2899 extern int __cond_resched_lock(spinlock_t *lock);
2900
2901 #define cond_resched_lock(lock) ({ \
2902 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
2903 __cond_resched_lock(lock); \
2904 })
2905
2906 extern int __cond_resched_softirq(void);
2907
2908 #define cond_resched_softirq() ({ \
2909 ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \
2910 __cond_resched_softirq(); \
2911 })
2912
2913 static inline void cond_resched_rcu(void)
2914 {
2915 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
2916 rcu_read_unlock();
2917 cond_resched();
2918 rcu_read_lock();
2919 #endif
2920 }
2921
2922 /*
2923 * Does a critical section need to be broken due to another
2924 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2925 * but a general need for low latency)
2926 */
2927 static inline int spin_needbreak(spinlock_t *lock)
2928 {
2929 #ifdef CONFIG_PREEMPT
2930 return spin_is_contended(lock);
2931 #else
2932 return 0;
2933 #endif
2934 }
2935
2936 static __always_inline bool need_resched(void)
2937 {
2938 return unlikely(tif_need_resched());
2939 }
2940
2941 /*
2942 * Thread group CPU time accounting.
2943 */
2944 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
2945 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
2946
2947 /*
2948 * Reevaluate whether the task has signals pending delivery.
2949 * Wake the task if so.
2950 * This is required every time the blocked sigset_t changes.
2951 * callers must hold sighand->siglock.
2952 */
2953 extern void recalc_sigpending_and_wake(struct task_struct *t);
2954 extern void recalc_sigpending(void);
2955
2956 extern void signal_wake_up_state(struct task_struct *t, unsigned int state);
2957
2958 static inline void signal_wake_up(struct task_struct *t, bool resume)
2959 {
2960 signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
2961 }
2962 static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
2963 {
2964 signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
2965 }
2966
2967 /*
2968 * Wrappers for p->thread_info->cpu access. No-op on UP.
2969 */
2970 #ifdef CONFIG_SMP
2971
2972 static inline unsigned int task_cpu(const struct task_struct *p)
2973 {
2974 #ifdef CONFIG_THREAD_INFO_IN_TASK
2975 return p->cpu;
2976 #else
2977 return task_thread_info(p)->cpu;
2978 #endif
2979 }
2980
2981 static inline int task_node(const struct task_struct *p)
2982 {
2983 return cpu_to_node(task_cpu(p));
2984 }
2985
2986 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
2987
2988 #else
2989
2990 static inline unsigned int task_cpu(const struct task_struct *p)
2991 {
2992 return 0;
2993 }
2994
2995 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
2996 {
2997 }
2998
2999 #endif /* CONFIG_SMP */
3000
3001 /*
3002 * In order to reduce various lock holder preemption latencies provide an
3003 * interface to see if a vCPU is currently running or not.
3004 *
3005 * This allows us to terminate optimistic spin loops and block, analogous to
3006 * the native optimistic spin heuristic of testing if the lock owner task is
3007 * running or not.
3008 */
3009 #ifndef vcpu_is_preempted
3010 # define vcpu_is_preempted(cpu) false
3011 #endif
3012
3013 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
3014 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
3015
3016 #ifdef CONFIG_CGROUP_SCHED
3017 extern struct task_group root_task_group;
3018 #endif /* CONFIG_CGROUP_SCHED */
3019
3020 extern int task_can_switch_user(struct user_struct *up,
3021 struct task_struct *tsk);
3022
3023 #ifdef CONFIG_TASK_XACCT
3024 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3025 {
3026 tsk->ioac.rchar += amt;
3027 }
3028
3029 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3030 {
3031 tsk->ioac.wchar += amt;
3032 }
3033
3034 static inline void inc_syscr(struct task_struct *tsk)
3035 {
3036 tsk->ioac.syscr++;
3037 }
3038
3039 static inline void inc_syscw(struct task_struct *tsk)
3040 {
3041 tsk->ioac.syscw++;
3042 }
3043 #else
3044 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3045 {
3046 }
3047
3048 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3049 {
3050 }
3051
3052 static inline void inc_syscr(struct task_struct *tsk)
3053 {
3054 }
3055
3056 static inline void inc_syscw(struct task_struct *tsk)
3057 {
3058 }
3059 #endif
3060
3061 #ifndef TASK_SIZE_OF
3062 #define TASK_SIZE_OF(tsk) TASK_SIZE
3063 #endif
3064
3065 #ifdef CONFIG_MEMCG
3066 extern void mm_update_next_owner(struct mm_struct *mm);
3067 #else
3068 static inline void mm_update_next_owner(struct mm_struct *mm)
3069 {
3070 }
3071 #endif /* CONFIG_MEMCG */
3072
3073 static inline unsigned long task_rlimit(const struct task_struct *tsk,
3074 unsigned int limit)
3075 {
3076 return READ_ONCE(tsk->signal->rlim[limit].rlim_cur);
3077 }
3078
3079 static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
3080 unsigned int limit)
3081 {
3082 return READ_ONCE(tsk->signal->rlim[limit].rlim_max);
3083 }
3084
3085 static inline unsigned long rlimit(unsigned int limit)
3086 {
3087 return task_rlimit(current, limit);
3088 }
3089
3090 static inline unsigned long rlimit_max(unsigned int limit)
3091 {
3092 return task_rlimit_max(current, limit);
3093 }
3094
3095 #define SCHED_CPUFREQ_RT (1U << 0)
3096 #define SCHED_CPUFREQ_DL (1U << 1)
3097 #define SCHED_CPUFREQ_IOWAIT (1U << 2)
3098
3099 #define SCHED_CPUFREQ_RT_DL (SCHED_CPUFREQ_RT | SCHED_CPUFREQ_DL)
3100
3101 #ifdef CONFIG_CPU_FREQ
3102 struct update_util_data {
3103 void (*func)(struct update_util_data *data, u64 time, unsigned int flags);
3104 };
3105
3106 void cpufreq_add_update_util_hook(int cpu, struct update_util_data *data,
3107 void (*func)(struct update_util_data *data, u64 time,
3108 unsigned int flags));
3109 void cpufreq_remove_update_util_hook(int cpu);
3110 #endif /* CONFIG_CPU_FREQ */
3111
3112 #endif