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