Merge branch 'for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
[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.h>
29
30 #include <asm/page.h>
31 #include <asm/ptrace.h>
32 #include <linux/cputime.h>
33
34 #include <linux/smp.h>
35 #include <linux/sem.h>
36 #include <linux/shm.h>
37 #include <linux/signal.h>
38 #include <linux/compiler.h>
39 #include <linux/completion.h>
40 #include <linux/pid.h>
41 #include <linux/percpu.h>
42 #include <linux/topology.h>
43 #include <linux/proportions.h>
44 #include <linux/seccomp.h>
45 #include <linux/rcupdate.h>
46 #include <linux/rculist.h>
47 #include <linux/rtmutex.h>
48
49 #include <linux/time.h>
50 #include <linux/param.h>
51 #include <linux/resource.h>
52 #include <linux/timer.h>
53 #include <linux/hrtimer.h>
54 #include <linux/task_io_accounting.h>
55 #include <linux/latencytop.h>
56 #include <linux/cred.h>
57 #include <linux/llist.h>
58 #include <linux/uidgid.h>
59 #include <linux/gfp.h>
60 #include <linux/magic.h>
61 #include <linux/cgroup-defs.h>
62
63 #include <asm/processor.h>
64
65 #define SCHED_ATTR_SIZE_VER0 48 /* sizeof first published struct */
66
67 /*
68 * Extended scheduling parameters data structure.
69 *
70 * This is needed because the original struct sched_param can not be
71 * altered without introducing ABI issues with legacy applications
72 * (e.g., in sched_getparam()).
73 *
74 * However, the possibility of specifying more than just a priority for
75 * the tasks may be useful for a wide variety of application fields, e.g.,
76 * multimedia, streaming, automation and control, and many others.
77 *
78 * This variant (sched_attr) is meant at describing a so-called
79 * sporadic time-constrained task. In such model a task is specified by:
80 * - the activation period or minimum instance inter-arrival time;
81 * - the maximum (or average, depending on the actual scheduling
82 * discipline) computation time of all instances, a.k.a. runtime;
83 * - the deadline (relative to the actual activation time) of each
84 * instance.
85 * Very briefly, a periodic (sporadic) task asks for the execution of
86 * some specific computation --which is typically called an instance--
87 * (at most) every period. Moreover, each instance typically lasts no more
88 * than the runtime and must be completed by time instant t equal to
89 * the instance activation time + the deadline.
90 *
91 * This is reflected by the actual fields of the sched_attr structure:
92 *
93 * @size size of the structure, for fwd/bwd compat.
94 *
95 * @sched_policy task's scheduling policy
96 * @sched_flags for customizing the scheduler behaviour
97 * @sched_nice task's nice value (SCHED_NORMAL/BATCH)
98 * @sched_priority task's static priority (SCHED_FIFO/RR)
99 * @sched_deadline representative of the task's deadline
100 * @sched_runtime representative of the task's runtime
101 * @sched_period representative of the task's period
102 *
103 * Given this task model, there are a multiplicity of scheduling algorithms
104 * and policies, that can be used to ensure all the tasks will make their
105 * timing constraints.
106 *
107 * As of now, the SCHED_DEADLINE policy (sched_dl scheduling class) is the
108 * only user of this new interface. More information about the algorithm
109 * available in the scheduling class file or in Documentation/.
110 */
111 struct sched_attr {
112 u32 size;
113
114 u32 sched_policy;
115 u64 sched_flags;
116
117 /* SCHED_NORMAL, SCHED_BATCH */
118 s32 sched_nice;
119
120 /* SCHED_FIFO, SCHED_RR */
121 u32 sched_priority;
122
123 /* SCHED_DEADLINE */
124 u64 sched_runtime;
125 u64 sched_deadline;
126 u64 sched_period;
127 };
128
129 struct futex_pi_state;
130 struct robust_list_head;
131 struct bio_list;
132 struct fs_struct;
133 struct perf_event_context;
134 struct blk_plug;
135 struct filename;
136 struct nameidata;
137
138 #define VMACACHE_BITS 2
139 #define VMACACHE_SIZE (1U << VMACACHE_BITS)
140 #define VMACACHE_MASK (VMACACHE_SIZE - 1)
141
142 /*
143 * These are the constant used to fake the fixed-point load-average
144 * counting. Some notes:
145 * - 11 bit fractions expand to 22 bits by the multiplies: this gives
146 * a load-average precision of 10 bits integer + 11 bits fractional
147 * - if you want to count load-averages more often, you need more
148 * precision, or rounding will get you. With 2-second counting freq,
149 * the EXP_n values would be 1981, 2034 and 2043 if still using only
150 * 11 bit fractions.
151 */
152 extern unsigned long avenrun[]; /* Load averages */
153 extern void get_avenrun(unsigned long *loads, unsigned long offset, int shift);
154
155 #define FSHIFT 11 /* nr of bits of precision */
156 #define FIXED_1 (1<<FSHIFT) /* 1.0 as fixed-point */
157 #define LOAD_FREQ (5*HZ+1) /* 5 sec intervals */
158 #define EXP_1 1884 /* 1/exp(5sec/1min) as fixed-point */
159 #define EXP_5 2014 /* 1/exp(5sec/5min) */
160 #define EXP_15 2037 /* 1/exp(5sec/15min) */
161
162 #define CALC_LOAD(load,exp,n) \
163 load *= exp; \
164 load += n*(FIXED_1-exp); \
165 load >>= FSHIFT;
166
167 extern unsigned long total_forks;
168 extern int nr_threads;
169 DECLARE_PER_CPU(unsigned long, process_counts);
170 extern int nr_processes(void);
171 extern unsigned long nr_running(void);
172 extern bool single_task_running(void);
173 extern unsigned long nr_iowait(void);
174 extern unsigned long nr_iowait_cpu(int cpu);
175 extern void get_iowait_load(unsigned long *nr_waiters, unsigned long *load);
176
177 extern void calc_global_load(unsigned long ticks);
178
179 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
180 extern void update_cpu_load_nohz(void);
181 #else
182 static inline void update_cpu_load_nohz(void) { }
183 #endif
184
185 extern unsigned long get_parent_ip(unsigned long addr);
186
187 extern void dump_cpu_task(int cpu);
188
189 struct seq_file;
190 struct cfs_rq;
191 struct task_group;
192 #ifdef CONFIG_SCHED_DEBUG
193 extern void proc_sched_show_task(struct task_struct *p, struct seq_file *m);
194 extern void proc_sched_set_task(struct task_struct *p);
195 #endif
196
197 /*
198 * Task state bitmask. NOTE! These bits are also
199 * encoded in fs/proc/array.c: get_task_state().
200 *
201 * We have two separate sets of flags: task->state
202 * is about runnability, while task->exit_state are
203 * about the task exiting. Confusing, but this way
204 * modifying one set can't modify the other one by
205 * mistake.
206 */
207 #define TASK_RUNNING 0
208 #define TASK_INTERRUPTIBLE 1
209 #define TASK_UNINTERRUPTIBLE 2
210 #define __TASK_STOPPED 4
211 #define __TASK_TRACED 8
212 /* in tsk->exit_state */
213 #define EXIT_DEAD 16
214 #define EXIT_ZOMBIE 32
215 #define EXIT_TRACE (EXIT_ZOMBIE | EXIT_DEAD)
216 /* in tsk->state again */
217 #define TASK_DEAD 64
218 #define TASK_WAKEKILL 128
219 #define TASK_WAKING 256
220 #define TASK_PARKED 512
221 #define TASK_NOLOAD 1024
222 #define TASK_STATE_MAX 2048
223
224 #define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPN"
225
226 extern char ___assert_task_state[1 - 2*!!(
227 sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)];
228
229 /* Convenience macros for the sake of set_task_state */
230 #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
231 #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
232 #define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED)
233
234 #define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
235
236 /* Convenience macros for the sake of wake_up */
237 #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE)
238 #define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED)
239
240 /* get_task_state() */
241 #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \
242 TASK_UNINTERRUPTIBLE | __TASK_STOPPED | \
243 __TASK_TRACED | EXIT_ZOMBIE | EXIT_DEAD)
244
245 #define task_is_traced(task) ((task->state & __TASK_TRACED) != 0)
246 #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0)
247 #define task_is_stopped_or_traced(task) \
248 ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0)
249 #define task_contributes_to_load(task) \
250 ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \
251 (task->flags & PF_FROZEN) == 0 && \
252 (task->state & TASK_NOLOAD) == 0)
253
254 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
255
256 #define __set_task_state(tsk, state_value) \
257 do { \
258 (tsk)->task_state_change = _THIS_IP_; \
259 (tsk)->state = (state_value); \
260 } while (0)
261 #define set_task_state(tsk, state_value) \
262 do { \
263 (tsk)->task_state_change = _THIS_IP_; \
264 smp_store_mb((tsk)->state, (state_value)); \
265 } while (0)
266
267 /*
268 * set_current_state() includes a barrier so that the write of current->state
269 * is correctly serialised wrt the caller's subsequent test of whether to
270 * actually sleep:
271 *
272 * set_current_state(TASK_UNINTERRUPTIBLE);
273 * if (do_i_need_to_sleep())
274 * schedule();
275 *
276 * If the caller does not need such serialisation then use __set_current_state()
277 */
278 #define __set_current_state(state_value) \
279 do { \
280 current->task_state_change = _THIS_IP_; \
281 current->state = (state_value); \
282 } while (0)
283 #define set_current_state(state_value) \
284 do { \
285 current->task_state_change = _THIS_IP_; \
286 smp_store_mb(current->state, (state_value)); \
287 } while (0)
288
289 #else
290
291 #define __set_task_state(tsk, state_value) \
292 do { (tsk)->state = (state_value); } while (0)
293 #define set_task_state(tsk, state_value) \
294 smp_store_mb((tsk)->state, (state_value))
295
296 /*
297 * set_current_state() includes a barrier so that the write of current->state
298 * is correctly serialised wrt the caller's subsequent test of whether to
299 * actually sleep:
300 *
301 * set_current_state(TASK_UNINTERRUPTIBLE);
302 * if (do_i_need_to_sleep())
303 * schedule();
304 *
305 * If the caller does not need such serialisation then use __set_current_state()
306 */
307 #define __set_current_state(state_value) \
308 do { current->state = (state_value); } while (0)
309 #define set_current_state(state_value) \
310 smp_store_mb(current->state, (state_value))
311
312 #endif
313
314 /* Task command name length */
315 #define TASK_COMM_LEN 16
316
317 #include <linux/spinlock.h>
318
319 /*
320 * This serializes "schedule()" and also protects
321 * the run-queue from deletions/modifications (but
322 * _adding_ to the beginning of the run-queue has
323 * a separate lock).
324 */
325 extern rwlock_t tasklist_lock;
326 extern spinlock_t mmlist_lock;
327
328 struct task_struct;
329
330 #ifdef CONFIG_PROVE_RCU
331 extern int lockdep_tasklist_lock_is_held(void);
332 #endif /* #ifdef CONFIG_PROVE_RCU */
333
334 extern void sched_init(void);
335 extern void sched_init_smp(void);
336 extern asmlinkage void schedule_tail(struct task_struct *prev);
337 extern void init_idle(struct task_struct *idle, int cpu);
338 extern void init_idle_bootup_task(struct task_struct *idle);
339
340 extern cpumask_var_t cpu_isolated_map;
341
342 extern int runqueue_is_locked(int cpu);
343
344 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
345 extern void nohz_balance_enter_idle(int cpu);
346 extern void set_cpu_sd_state_idle(void);
347 extern int get_nohz_timer_target(void);
348 #else
349 static inline void nohz_balance_enter_idle(int cpu) { }
350 static inline void set_cpu_sd_state_idle(void) { }
351 #endif
352
353 /*
354 * Only dump TASK_* tasks. (0 for all tasks)
355 */
356 extern void show_state_filter(unsigned long state_filter);
357
358 static inline void show_state(void)
359 {
360 show_state_filter(0);
361 }
362
363 extern void show_regs(struct pt_regs *);
364
365 /*
366 * TASK is a pointer to the task whose backtrace we want to see (or NULL for current
367 * task), SP is the stack pointer of the first frame that should be shown in the back
368 * trace (or NULL if the entire call-chain of the task should be shown).
369 */
370 extern void show_stack(struct task_struct *task, unsigned long *sp);
371
372 extern void cpu_init (void);
373 extern void trap_init(void);
374 extern void update_process_times(int user);
375 extern void scheduler_tick(void);
376
377 extern void sched_show_task(struct task_struct *p);
378
379 #ifdef CONFIG_LOCKUP_DETECTOR
380 extern void touch_softlockup_watchdog(void);
381 extern void touch_softlockup_watchdog_sync(void);
382 extern void touch_all_softlockup_watchdogs(void);
383 extern int proc_dowatchdog_thresh(struct ctl_table *table, int write,
384 void __user *buffer,
385 size_t *lenp, loff_t *ppos);
386 extern unsigned int softlockup_panic;
387 void lockup_detector_init(void);
388 #else
389 static inline void touch_softlockup_watchdog(void)
390 {
391 }
392 static inline void touch_softlockup_watchdog_sync(void)
393 {
394 }
395 static inline void touch_all_softlockup_watchdogs(void)
396 {
397 }
398 static inline void lockup_detector_init(void)
399 {
400 }
401 #endif
402
403 #ifdef CONFIG_DETECT_HUNG_TASK
404 void reset_hung_task_detector(void);
405 #else
406 static inline void reset_hung_task_detector(void)
407 {
408 }
409 #endif
410
411 /* Attach to any functions which should be ignored in wchan output. */
412 #define __sched __attribute__((__section__(".sched.text")))
413
414 /* Linker adds these: start and end of __sched functions */
415 extern char __sched_text_start[], __sched_text_end[];
416
417 /* Is this address in the __sched functions? */
418 extern int in_sched_functions(unsigned long addr);
419
420 #define MAX_SCHEDULE_TIMEOUT LONG_MAX
421 extern signed long schedule_timeout(signed long timeout);
422 extern signed long schedule_timeout_interruptible(signed long timeout);
423 extern signed long schedule_timeout_killable(signed long timeout);
424 extern signed long schedule_timeout_uninterruptible(signed long timeout);
425 asmlinkage void schedule(void);
426 extern void schedule_preempt_disabled(void);
427
428 extern long io_schedule_timeout(long timeout);
429
430 static inline void io_schedule(void)
431 {
432 io_schedule_timeout(MAX_SCHEDULE_TIMEOUT);
433 }
434
435 struct nsproxy;
436 struct user_namespace;
437
438 #ifdef CONFIG_MMU
439 extern void arch_pick_mmap_layout(struct mm_struct *mm);
440 extern unsigned long
441 arch_get_unmapped_area(struct file *, unsigned long, unsigned long,
442 unsigned long, unsigned long);
443 extern unsigned long
444 arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr,
445 unsigned long len, unsigned long pgoff,
446 unsigned long flags);
447 #else
448 static inline void arch_pick_mmap_layout(struct mm_struct *mm) {}
449 #endif
450
451 #define SUID_DUMP_DISABLE 0 /* No setuid dumping */
452 #define SUID_DUMP_USER 1 /* Dump as user of process */
453 #define SUID_DUMP_ROOT 2 /* Dump as root */
454
455 /* mm flags */
456
457 /* for SUID_DUMP_* above */
458 #define MMF_DUMPABLE_BITS 2
459 #define MMF_DUMPABLE_MASK ((1 << MMF_DUMPABLE_BITS) - 1)
460
461 extern void set_dumpable(struct mm_struct *mm, int value);
462 /*
463 * This returns the actual value of the suid_dumpable flag. For things
464 * that are using this for checking for privilege transitions, it must
465 * test against SUID_DUMP_USER rather than treating it as a boolean
466 * value.
467 */
468 static inline int __get_dumpable(unsigned long mm_flags)
469 {
470 return mm_flags & MMF_DUMPABLE_MASK;
471 }
472
473 static inline int get_dumpable(struct mm_struct *mm)
474 {
475 return __get_dumpable(mm->flags);
476 }
477
478 /* coredump filter bits */
479 #define MMF_DUMP_ANON_PRIVATE 2
480 #define MMF_DUMP_ANON_SHARED 3
481 #define MMF_DUMP_MAPPED_PRIVATE 4
482 #define MMF_DUMP_MAPPED_SHARED 5
483 #define MMF_DUMP_ELF_HEADERS 6
484 #define MMF_DUMP_HUGETLB_PRIVATE 7
485 #define MMF_DUMP_HUGETLB_SHARED 8
486
487 #define MMF_DUMP_FILTER_SHIFT MMF_DUMPABLE_BITS
488 #define MMF_DUMP_FILTER_BITS 7
489 #define MMF_DUMP_FILTER_MASK \
490 (((1 << MMF_DUMP_FILTER_BITS) - 1) << MMF_DUMP_FILTER_SHIFT)
491 #define MMF_DUMP_FILTER_DEFAULT \
492 ((1 << MMF_DUMP_ANON_PRIVATE) | (1 << MMF_DUMP_ANON_SHARED) |\
493 (1 << MMF_DUMP_HUGETLB_PRIVATE) | MMF_DUMP_MASK_DEFAULT_ELF)
494
495 #ifdef CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS
496 # define MMF_DUMP_MASK_DEFAULT_ELF (1 << MMF_DUMP_ELF_HEADERS)
497 #else
498 # define MMF_DUMP_MASK_DEFAULT_ELF 0
499 #endif
500 /* leave room for more dump flags */
501 #define MMF_VM_MERGEABLE 16 /* KSM may merge identical pages */
502 #define MMF_VM_HUGEPAGE 17 /* set when VM_HUGEPAGE is set on vma */
503 #define MMF_EXE_FILE_CHANGED 18 /* see prctl_set_mm_exe_file() */
504
505 #define MMF_HAS_UPROBES 19 /* has uprobes */
506 #define MMF_RECALC_UPROBES 20 /* MMF_HAS_UPROBES can be wrong */
507
508 #define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK)
509
510 struct sighand_struct {
511 atomic_t count;
512 struct k_sigaction action[_NSIG];
513 spinlock_t siglock;
514 wait_queue_head_t signalfd_wqh;
515 };
516
517 struct pacct_struct {
518 int ac_flag;
519 long ac_exitcode;
520 unsigned long ac_mem;
521 cputime_t ac_utime, ac_stime;
522 unsigned long ac_minflt, ac_majflt;
523 };
524
525 struct cpu_itimer {
526 cputime_t expires;
527 cputime_t incr;
528 u32 error;
529 u32 incr_error;
530 };
531
532 /**
533 * struct prev_cputime - snaphsot of system and user cputime
534 * @utime: time spent in user mode
535 * @stime: time spent in system mode
536 * @lock: protects the above two fields
537 *
538 * Stores previous user/system time values such that we can guarantee
539 * monotonicity.
540 */
541 struct prev_cputime {
542 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
543 cputime_t utime;
544 cputime_t stime;
545 raw_spinlock_t lock;
546 #endif
547 };
548
549 static inline void prev_cputime_init(struct prev_cputime *prev)
550 {
551 #ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
552 prev->utime = prev->stime = 0;
553 raw_spin_lock_init(&prev->lock);
554 #endif
555 }
556
557 /**
558 * struct task_cputime - collected CPU time counts
559 * @utime: time spent in user mode, in &cputime_t units
560 * @stime: time spent in kernel mode, in &cputime_t units
561 * @sum_exec_runtime: total time spent on the CPU, in nanoseconds
562 *
563 * This structure groups together three kinds of CPU time that are tracked for
564 * threads and thread groups. Most things considering CPU time want to group
565 * these counts together and treat all three of them in parallel.
566 */
567 struct task_cputime {
568 cputime_t utime;
569 cputime_t stime;
570 unsigned long long sum_exec_runtime;
571 };
572
573 /* Alternate field names when used to cache expirations. */
574 #define virt_exp utime
575 #define prof_exp stime
576 #define sched_exp sum_exec_runtime
577
578 #define INIT_CPUTIME \
579 (struct task_cputime) { \
580 .utime = 0, \
581 .stime = 0, \
582 .sum_exec_runtime = 0, \
583 }
584
585 /*
586 * This is the atomic variant of task_cputime, which can be used for
587 * storing and updating task_cputime statistics without locking.
588 */
589 struct task_cputime_atomic {
590 atomic64_t utime;
591 atomic64_t stime;
592 atomic64_t sum_exec_runtime;
593 };
594
595 #define INIT_CPUTIME_ATOMIC \
596 (struct task_cputime_atomic) { \
597 .utime = ATOMIC64_INIT(0), \
598 .stime = ATOMIC64_INIT(0), \
599 .sum_exec_runtime = ATOMIC64_INIT(0), \
600 }
601
602 #define PREEMPT_DISABLED (PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
603
604 /*
605 * Disable preemption until the scheduler is running -- use an unconditional
606 * value so that it also works on !PREEMPT_COUNT kernels.
607 *
608 * Reset by start_kernel()->sched_init()->init_idle()->init_idle_preempt_count().
609 */
610 #define INIT_PREEMPT_COUNT PREEMPT_OFFSET
611
612 /*
613 * Initial preempt_count value; reflects the preempt_count schedule invariant
614 * which states that during context switches:
615 *
616 * preempt_count() == 2*PREEMPT_DISABLE_OFFSET
617 *
618 * Note: PREEMPT_DISABLE_OFFSET is 0 for !PREEMPT_COUNT kernels.
619 * Note: See finish_task_switch().
620 */
621 #define FORK_PREEMPT_COUNT (2*PREEMPT_DISABLE_OFFSET + PREEMPT_ENABLED)
622
623 /**
624 * struct thread_group_cputimer - thread group interval timer counts
625 * @cputime_atomic: atomic thread group interval timers.
626 * @running: true when there are timers running and
627 * @cputime_atomic receives updates.
628 * @checking_timer: true when a thread in the group is in the
629 * process of checking for thread group timers.
630 *
631 * This structure contains the version of task_cputime, above, that is
632 * used for thread group CPU timer calculations.
633 */
634 struct thread_group_cputimer {
635 struct task_cputime_atomic cputime_atomic;
636 bool running;
637 bool checking_timer;
638 };
639
640 #include <linux/rwsem.h>
641 struct autogroup;
642
643 /*
644 * NOTE! "signal_struct" does not have its own
645 * locking, because a shared signal_struct always
646 * implies a shared sighand_struct, so locking
647 * sighand_struct is always a proper superset of
648 * the locking of signal_struct.
649 */
650 struct signal_struct {
651 atomic_t sigcnt;
652 atomic_t live;
653 int nr_threads;
654 struct list_head thread_head;
655
656 wait_queue_head_t wait_chldexit; /* for wait4() */
657
658 /* current thread group signal load-balancing target: */
659 struct task_struct *curr_target;
660
661 /* shared signal handling: */
662 struct sigpending shared_pending;
663
664 /* thread group exit support */
665 int group_exit_code;
666 /* overloaded:
667 * - notify group_exit_task when ->count is equal to notify_count
668 * - everyone except group_exit_task is stopped during signal delivery
669 * of fatal signals, group_exit_task processes the signal.
670 */
671 int notify_count;
672 struct task_struct *group_exit_task;
673
674 /* thread group stop support, overloads group_exit_code too */
675 int group_stop_count;
676 unsigned int flags; /* see SIGNAL_* flags below */
677
678 /*
679 * PR_SET_CHILD_SUBREAPER marks a process, like a service
680 * manager, to re-parent orphan (double-forking) child processes
681 * to this process instead of 'init'. The service manager is
682 * able to receive SIGCHLD signals and is able to investigate
683 * the process until it calls wait(). All children of this
684 * process will inherit a flag if they should look for a
685 * child_subreaper process at exit.
686 */
687 unsigned int is_child_subreaper:1;
688 unsigned int has_child_subreaper:1;
689
690 /* POSIX.1b Interval Timers */
691 int posix_timer_id;
692 struct list_head posix_timers;
693
694 /* ITIMER_REAL timer for the process */
695 struct hrtimer real_timer;
696 struct pid *leader_pid;
697 ktime_t it_real_incr;
698
699 /*
700 * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
701 * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
702 * values are defined to 0 and 1 respectively
703 */
704 struct cpu_itimer it[2];
705
706 /*
707 * Thread group totals for process CPU timers.
708 * See thread_group_cputimer(), et al, for details.
709 */
710 struct thread_group_cputimer cputimer;
711
712 /* Earliest-expiration cache. */
713 struct task_cputime cputime_expires;
714
715 struct list_head cpu_timers[3];
716
717 struct pid *tty_old_pgrp;
718
719 /* boolean value for session group leader */
720 int leader;
721
722 struct tty_struct *tty; /* NULL if no tty */
723
724 #ifdef CONFIG_SCHED_AUTOGROUP
725 struct autogroup *autogroup;
726 #endif
727 /*
728 * Cumulative resource counters for dead threads in the group,
729 * and for reaped dead child processes forked by this group.
730 * Live threads maintain their own counters and add to these
731 * in __exit_signal, except for the group leader.
732 */
733 seqlock_t stats_lock;
734 cputime_t utime, stime, cutime, cstime;
735 cputime_t gtime;
736 cputime_t cgtime;
737 struct prev_cputime prev_cputime;
738 unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
739 unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
740 unsigned long inblock, oublock, cinblock, coublock;
741 unsigned long maxrss, cmaxrss;
742 struct task_io_accounting ioac;
743
744 /*
745 * Cumulative ns of schedule CPU time fo dead threads in the
746 * group, not including a zombie group leader, (This only differs
747 * from jiffies_to_ns(utime + stime) if sched_clock uses something
748 * other than jiffies.)
749 */
750 unsigned long long sum_sched_runtime;
751
752 /*
753 * We don't bother to synchronize most readers of this at all,
754 * because there is no reader checking a limit that actually needs
755 * to get both rlim_cur and rlim_max atomically, and either one
756 * alone is a single word that can safely be read normally.
757 * getrlimit/setrlimit use task_lock(current->group_leader) to
758 * protect this instead of the siglock, because they really
759 * have no need to disable irqs.
760 */
761 struct rlimit rlim[RLIM_NLIMITS];
762
763 #ifdef CONFIG_BSD_PROCESS_ACCT
764 struct pacct_struct pacct; /* per-process accounting information */
765 #endif
766 #ifdef CONFIG_TASKSTATS
767 struct taskstats *stats;
768 #endif
769 #ifdef CONFIG_AUDIT
770 unsigned audit_tty;
771 unsigned audit_tty_log_passwd;
772 struct tty_audit_buf *tty_audit_buf;
773 #endif
774
775 oom_flags_t oom_flags;
776 short oom_score_adj; /* OOM kill score adjustment */
777 short oom_score_adj_min; /* OOM kill score adjustment min value.
778 * Only settable by CAP_SYS_RESOURCE. */
779
780 struct mutex cred_guard_mutex; /* guard against foreign influences on
781 * credential calculations
782 * (notably. ptrace) */
783 };
784
785 /*
786 * Bits in flags field of signal_struct.
787 */
788 #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */
789 #define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */
790 #define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */
791 #define SIGNAL_GROUP_COREDUMP 0x00000008 /* coredump in progress */
792 /*
793 * Pending notifications to parent.
794 */
795 #define SIGNAL_CLD_STOPPED 0x00000010
796 #define SIGNAL_CLD_CONTINUED 0x00000020
797 #define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
798
799 #define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */
800
801 /* If true, all threads except ->group_exit_task have pending SIGKILL */
802 static inline int signal_group_exit(const struct signal_struct *sig)
803 {
804 return (sig->flags & SIGNAL_GROUP_EXIT) ||
805 (sig->group_exit_task != NULL);
806 }
807
808 /*
809 * Some day this will be a full-fledged user tracking system..
810 */
811 struct user_struct {
812 atomic_t __count; /* reference count */
813 atomic_t processes; /* How many processes does this user have? */
814 atomic_t sigpending; /* How many pending signals does this user have? */
815 #ifdef CONFIG_INOTIFY_USER
816 atomic_t inotify_watches; /* How many inotify watches does this user have? */
817 atomic_t inotify_devs; /* How many inotify devs does this user have opened? */
818 #endif
819 #ifdef CONFIG_FANOTIFY
820 atomic_t fanotify_listeners;
821 #endif
822 #ifdef CONFIG_EPOLL
823 atomic_long_t epoll_watches; /* The number of file descriptors currently watched */
824 #endif
825 #ifdef CONFIG_POSIX_MQUEUE
826 /* protected by mq_lock */
827 unsigned long mq_bytes; /* How many bytes can be allocated to mqueue? */
828 #endif
829 unsigned long locked_shm; /* How many pages of mlocked shm ? */
830
831 #ifdef CONFIG_KEYS
832 struct key *uid_keyring; /* UID specific keyring */
833 struct key *session_keyring; /* UID's default session keyring */
834 #endif
835
836 /* Hash table maintenance information */
837 struct hlist_node uidhash_node;
838 kuid_t uid;
839
840 #if defined(CONFIG_PERF_EVENTS) || defined(CONFIG_BPF_SYSCALL)
841 atomic_long_t locked_vm;
842 #endif
843 };
844
845 extern int uids_sysfs_init(void);
846
847 extern struct user_struct *find_user(kuid_t);
848
849 extern struct user_struct root_user;
850 #define INIT_USER (&root_user)
851
852
853 struct backing_dev_info;
854 struct reclaim_state;
855
856 #ifdef CONFIG_SCHED_INFO
857 struct sched_info {
858 /* cumulative counters */
859 unsigned long pcount; /* # of times run on this cpu */
860 unsigned long long run_delay; /* time spent waiting on a runqueue */
861
862 /* timestamps */
863 unsigned long long last_arrival,/* when we last ran on a cpu */
864 last_queued; /* when we were last queued to run */
865 };
866 #endif /* CONFIG_SCHED_INFO */
867
868 #ifdef CONFIG_TASK_DELAY_ACCT
869 struct task_delay_info {
870 spinlock_t lock;
871 unsigned int flags; /* Private per-task flags */
872
873 /* For each stat XXX, add following, aligned appropriately
874 *
875 * struct timespec XXX_start, XXX_end;
876 * u64 XXX_delay;
877 * u32 XXX_count;
878 *
879 * Atomicity of updates to XXX_delay, XXX_count protected by
880 * single lock above (split into XXX_lock if contention is an issue).
881 */
882
883 /*
884 * XXX_count is incremented on every XXX operation, the delay
885 * associated with the operation is added to XXX_delay.
886 * XXX_delay contains the accumulated delay time in nanoseconds.
887 */
888 u64 blkio_start; /* Shared by blkio, swapin */
889 u64 blkio_delay; /* wait for sync block io completion */
890 u64 swapin_delay; /* wait for swapin block io completion */
891 u32 blkio_count; /* total count of the number of sync block */
892 /* io operations performed */
893 u32 swapin_count; /* total count of the number of swapin block */
894 /* io operations performed */
895
896 u64 freepages_start;
897 u64 freepages_delay; /* wait for memory reclaim */
898 u32 freepages_count; /* total count of memory reclaim */
899 };
900 #endif /* CONFIG_TASK_DELAY_ACCT */
901
902 static inline int sched_info_on(void)
903 {
904 #ifdef CONFIG_SCHEDSTATS
905 return 1;
906 #elif defined(CONFIG_TASK_DELAY_ACCT)
907 extern int delayacct_on;
908 return delayacct_on;
909 #else
910 return 0;
911 #endif
912 }
913
914 enum cpu_idle_type {
915 CPU_IDLE,
916 CPU_NOT_IDLE,
917 CPU_NEWLY_IDLE,
918 CPU_MAX_IDLE_TYPES
919 };
920
921 /*
922 * Increase resolution of cpu_capacity calculations
923 */
924 #define SCHED_CAPACITY_SHIFT 10
925 #define SCHED_CAPACITY_SCALE (1L << SCHED_CAPACITY_SHIFT)
926
927 /*
928 * Wake-queues are lists of tasks with a pending wakeup, whose
929 * callers have already marked the task as woken internally,
930 * and can thus carry on. A common use case is being able to
931 * do the wakeups once the corresponding user lock as been
932 * released.
933 *
934 * We hold reference to each task in the list across the wakeup,
935 * thus guaranteeing that the memory is still valid by the time
936 * the actual wakeups are performed in wake_up_q().
937 *
938 * One per task suffices, because there's never a need for a task to be
939 * in two wake queues simultaneously; it is forbidden to abandon a task
940 * in a wake queue (a call to wake_up_q() _must_ follow), so if a task is
941 * already in a wake queue, the wakeup will happen soon and the second
942 * waker can just skip it.
943 *
944 * The WAKE_Q macro declares and initializes the list head.
945 * wake_up_q() does NOT reinitialize the list; it's expected to be
946 * called near the end of a function, where the fact that the queue is
947 * not used again will be easy to see by inspection.
948 *
949 * Note that this can cause spurious wakeups. schedule() callers
950 * must ensure the call is done inside a loop, confirming that the
951 * wakeup condition has in fact occurred.
952 */
953 struct wake_q_node {
954 struct wake_q_node *next;
955 };
956
957 struct wake_q_head {
958 struct wake_q_node *first;
959 struct wake_q_node **lastp;
960 };
961
962 #define WAKE_Q_TAIL ((struct wake_q_node *) 0x01)
963
964 #define WAKE_Q(name) \
965 struct wake_q_head name = { WAKE_Q_TAIL, &name.first }
966
967 extern void wake_q_add(struct wake_q_head *head,
968 struct task_struct *task);
969 extern void wake_up_q(struct wake_q_head *head);
970
971 /*
972 * sched-domains (multiprocessor balancing) declarations:
973 */
974 #ifdef CONFIG_SMP
975 #define SD_LOAD_BALANCE 0x0001 /* Do load balancing on this domain. */
976 #define SD_BALANCE_NEWIDLE 0x0002 /* Balance when about to become idle */
977 #define SD_BALANCE_EXEC 0x0004 /* Balance on exec */
978 #define SD_BALANCE_FORK 0x0008 /* Balance on fork, clone */
979 #define SD_BALANCE_WAKE 0x0010 /* Balance on wakeup */
980 #define SD_WAKE_AFFINE 0x0020 /* Wake task to waking CPU */
981 #define SD_SHARE_CPUCAPACITY 0x0080 /* Domain members share cpu power */
982 #define SD_SHARE_POWERDOMAIN 0x0100 /* Domain members share power domain */
983 #define SD_SHARE_PKG_RESOURCES 0x0200 /* Domain members share cpu pkg resources */
984 #define SD_SERIALIZE 0x0400 /* Only a single load balancing instance */
985 #define SD_ASYM_PACKING 0x0800 /* Place busy groups earlier in the domain */
986 #define SD_PREFER_SIBLING 0x1000 /* Prefer to place tasks in a sibling domain */
987 #define SD_OVERLAP 0x2000 /* sched_domains of this level overlap */
988 #define SD_NUMA 0x4000 /* cross-node balancing */
989
990 #ifdef CONFIG_SCHED_SMT
991 static inline int cpu_smt_flags(void)
992 {
993 return SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES;
994 }
995 #endif
996
997 #ifdef CONFIG_SCHED_MC
998 static inline int cpu_core_flags(void)
999 {
1000 return SD_SHARE_PKG_RESOURCES;
1001 }
1002 #endif
1003
1004 #ifdef CONFIG_NUMA
1005 static inline int cpu_numa_flags(void)
1006 {
1007 return SD_NUMA;
1008 }
1009 #endif
1010
1011 struct sched_domain_attr {
1012 int relax_domain_level;
1013 };
1014
1015 #define SD_ATTR_INIT (struct sched_domain_attr) { \
1016 .relax_domain_level = -1, \
1017 }
1018
1019 extern int sched_domain_level_max;
1020
1021 struct sched_group;
1022
1023 struct sched_domain {
1024 /* These fields must be setup */
1025 struct sched_domain *parent; /* top domain must be null terminated */
1026 struct sched_domain *child; /* bottom domain must be null terminated */
1027 struct sched_group *groups; /* the balancing groups of the domain */
1028 unsigned long min_interval; /* Minimum balance interval ms */
1029 unsigned long max_interval; /* Maximum balance interval ms */
1030 unsigned int busy_factor; /* less balancing by factor if busy */
1031 unsigned int imbalance_pct; /* No balance until over watermark */
1032 unsigned int cache_nice_tries; /* Leave cache hot tasks for # tries */
1033 unsigned int busy_idx;
1034 unsigned int idle_idx;
1035 unsigned int newidle_idx;
1036 unsigned int wake_idx;
1037 unsigned int forkexec_idx;
1038 unsigned int smt_gain;
1039
1040 int nohz_idle; /* NOHZ IDLE status */
1041 int flags; /* See SD_* */
1042 int level;
1043
1044 /* Runtime fields. */
1045 unsigned long last_balance; /* init to jiffies. units in jiffies */
1046 unsigned int balance_interval; /* initialise to 1. units in ms. */
1047 unsigned int nr_balance_failed; /* initialise to 0 */
1048
1049 /* idle_balance() stats */
1050 u64 max_newidle_lb_cost;
1051 unsigned long next_decay_max_lb_cost;
1052
1053 #ifdef CONFIG_SCHEDSTATS
1054 /* load_balance() stats */
1055 unsigned int lb_count[CPU_MAX_IDLE_TYPES];
1056 unsigned int lb_failed[CPU_MAX_IDLE_TYPES];
1057 unsigned int lb_balanced[CPU_MAX_IDLE_TYPES];
1058 unsigned int lb_imbalance[CPU_MAX_IDLE_TYPES];
1059 unsigned int lb_gained[CPU_MAX_IDLE_TYPES];
1060 unsigned int lb_hot_gained[CPU_MAX_IDLE_TYPES];
1061 unsigned int lb_nobusyg[CPU_MAX_IDLE_TYPES];
1062 unsigned int lb_nobusyq[CPU_MAX_IDLE_TYPES];
1063
1064 /* Active load balancing */
1065 unsigned int alb_count;
1066 unsigned int alb_failed;
1067 unsigned int alb_pushed;
1068
1069 /* SD_BALANCE_EXEC stats */
1070 unsigned int sbe_count;
1071 unsigned int sbe_balanced;
1072 unsigned int sbe_pushed;
1073
1074 /* SD_BALANCE_FORK stats */
1075 unsigned int sbf_count;
1076 unsigned int sbf_balanced;
1077 unsigned int sbf_pushed;
1078
1079 /* try_to_wake_up() stats */
1080 unsigned int ttwu_wake_remote;
1081 unsigned int ttwu_move_affine;
1082 unsigned int ttwu_move_balance;
1083 #endif
1084 #ifdef CONFIG_SCHED_DEBUG
1085 char *name;
1086 #endif
1087 union {
1088 void *private; /* used during construction */
1089 struct rcu_head rcu; /* used during destruction */
1090 };
1091
1092 unsigned int span_weight;
1093 /*
1094 * Span of all CPUs in this domain.
1095 *
1096 * NOTE: this field is variable length. (Allocated dynamically
1097 * by attaching extra space to the end of the structure,
1098 * depending on how many CPUs the kernel has booted up with)
1099 */
1100 unsigned long span[0];
1101 };
1102
1103 static inline struct cpumask *sched_domain_span(struct sched_domain *sd)
1104 {
1105 return to_cpumask(sd->span);
1106 }
1107
1108 extern void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1109 struct sched_domain_attr *dattr_new);
1110
1111 /* Allocate an array of sched domains, for partition_sched_domains(). */
1112 cpumask_var_t *alloc_sched_domains(unsigned int ndoms);
1113 void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms);
1114
1115 bool cpus_share_cache(int this_cpu, int that_cpu);
1116
1117 typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
1118 typedef int (*sched_domain_flags_f)(void);
1119
1120 #define SDTL_OVERLAP 0x01
1121
1122 struct sd_data {
1123 struct sched_domain **__percpu sd;
1124 struct sched_group **__percpu sg;
1125 struct sched_group_capacity **__percpu sgc;
1126 };
1127
1128 struct sched_domain_topology_level {
1129 sched_domain_mask_f mask;
1130 sched_domain_flags_f sd_flags;
1131 int flags;
1132 int numa_level;
1133 struct sd_data data;
1134 #ifdef CONFIG_SCHED_DEBUG
1135 char *name;
1136 #endif
1137 };
1138
1139 extern void set_sched_topology(struct sched_domain_topology_level *tl);
1140 extern void wake_up_if_idle(int cpu);
1141
1142 #ifdef CONFIG_SCHED_DEBUG
1143 # define SD_INIT_NAME(type) .name = #type
1144 #else
1145 # define SD_INIT_NAME(type)
1146 #endif
1147
1148 #else /* CONFIG_SMP */
1149
1150 struct sched_domain_attr;
1151
1152 static inline void
1153 partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
1154 struct sched_domain_attr *dattr_new)
1155 {
1156 }
1157
1158 static inline bool cpus_share_cache(int this_cpu, int that_cpu)
1159 {
1160 return true;
1161 }
1162
1163 #endif /* !CONFIG_SMP */
1164
1165
1166 struct io_context; /* See blkdev.h */
1167
1168
1169 #ifdef ARCH_HAS_PREFETCH_SWITCH_STACK
1170 extern void prefetch_stack(struct task_struct *t);
1171 #else
1172 static inline void prefetch_stack(struct task_struct *t) { }
1173 #endif
1174
1175 struct audit_context; /* See audit.c */
1176 struct mempolicy;
1177 struct pipe_inode_info;
1178 struct uts_namespace;
1179
1180 struct load_weight {
1181 unsigned long weight;
1182 u32 inv_weight;
1183 };
1184
1185 /*
1186 * The load_avg/util_avg accumulates an infinite geometric series.
1187 * 1) load_avg factors frequency scaling into the amount of time that a
1188 * sched_entity is runnable on a rq into its weight. For cfs_rq, it is the
1189 * aggregated such weights of all runnable and blocked sched_entities.
1190 * 2) util_avg factors frequency and cpu scaling into the amount of time
1191 * that a sched_entity is running on a CPU, in the range [0..SCHED_LOAD_SCALE].
1192 * For cfs_rq, it is the aggregated such times of all runnable and
1193 * blocked sched_entities.
1194 * The 64 bit load_sum can:
1195 * 1) for cfs_rq, afford 4353082796 (=2^64/47742/88761) entities with
1196 * the highest weight (=88761) always runnable, we should not overflow
1197 * 2) for entity, support any load.weight always runnable
1198 */
1199 struct sched_avg {
1200 u64 last_update_time, load_sum;
1201 u32 util_sum, period_contrib;
1202 unsigned long load_avg, util_avg;
1203 };
1204
1205 #ifdef CONFIG_SCHEDSTATS
1206 struct sched_statistics {
1207 u64 wait_start;
1208 u64 wait_max;
1209 u64 wait_count;
1210 u64 wait_sum;
1211 u64 iowait_count;
1212 u64 iowait_sum;
1213
1214 u64 sleep_start;
1215 u64 sleep_max;
1216 s64 sum_sleep_runtime;
1217
1218 u64 block_start;
1219 u64 block_max;
1220 u64 exec_max;
1221 u64 slice_max;
1222
1223 u64 nr_migrations_cold;
1224 u64 nr_failed_migrations_affine;
1225 u64 nr_failed_migrations_running;
1226 u64 nr_failed_migrations_hot;
1227 u64 nr_forced_migrations;
1228
1229 u64 nr_wakeups;
1230 u64 nr_wakeups_sync;
1231 u64 nr_wakeups_migrate;
1232 u64 nr_wakeups_local;
1233 u64 nr_wakeups_remote;
1234 u64 nr_wakeups_affine;
1235 u64 nr_wakeups_affine_attempts;
1236 u64 nr_wakeups_passive;
1237 u64 nr_wakeups_idle;
1238 };
1239 #endif
1240
1241 struct sched_entity {
1242 struct load_weight load; /* for load-balancing */
1243 struct rb_node run_node;
1244 struct list_head group_node;
1245 unsigned int on_rq;
1246
1247 u64 exec_start;
1248 u64 sum_exec_runtime;
1249 u64 vruntime;
1250 u64 prev_sum_exec_runtime;
1251
1252 u64 nr_migrations;
1253
1254 #ifdef CONFIG_SCHEDSTATS
1255 struct sched_statistics statistics;
1256 #endif
1257
1258 #ifdef CONFIG_FAIR_GROUP_SCHED
1259 int depth;
1260 struct sched_entity *parent;
1261 /* rq on which this entity is (to be) queued: */
1262 struct cfs_rq *cfs_rq;
1263 /* rq "owned" by this entity/group: */
1264 struct cfs_rq *my_q;
1265 #endif
1266
1267 #ifdef CONFIG_SMP
1268 /* Per entity load average tracking */
1269 struct sched_avg avg;
1270 #endif
1271 };
1272
1273 struct sched_rt_entity {
1274 struct list_head run_list;
1275 unsigned long timeout;
1276 unsigned long watchdog_stamp;
1277 unsigned int time_slice;
1278
1279 struct sched_rt_entity *back;
1280 #ifdef CONFIG_RT_GROUP_SCHED
1281 struct sched_rt_entity *parent;
1282 /* rq on which this entity is (to be) queued: */
1283 struct rt_rq *rt_rq;
1284 /* rq "owned" by this entity/group: */
1285 struct rt_rq *my_q;
1286 #endif
1287 };
1288
1289 struct sched_dl_entity {
1290 struct rb_node rb_node;
1291
1292 /*
1293 * Original scheduling parameters. Copied here from sched_attr
1294 * during sched_setattr(), they will remain the same until
1295 * the next sched_setattr().
1296 */
1297 u64 dl_runtime; /* maximum runtime for each instance */
1298 u64 dl_deadline; /* relative deadline of each instance */
1299 u64 dl_period; /* separation of two instances (period) */
1300 u64 dl_bw; /* dl_runtime / dl_deadline */
1301
1302 /*
1303 * Actual scheduling parameters. Initialized with the values above,
1304 * they are continously updated during task execution. Note that
1305 * the remaining runtime could be < 0 in case we are in overrun.
1306 */
1307 s64 runtime; /* remaining runtime for this instance */
1308 u64 deadline; /* absolute deadline for this instance */
1309 unsigned int flags; /* specifying the scheduler behaviour */
1310
1311 /*
1312 * Some bool flags:
1313 *
1314 * @dl_throttled tells if we exhausted the runtime. If so, the
1315 * task has to wait for a replenishment to be performed at the
1316 * next firing of dl_timer.
1317 *
1318 * @dl_new tells if a new instance arrived. If so we must
1319 * start executing it with full runtime and reset its absolute
1320 * deadline;
1321 *
1322 * @dl_boosted tells if we are boosted due to DI. If so we are
1323 * outside bandwidth enforcement mechanism (but only until we
1324 * exit the critical section);
1325 *
1326 * @dl_yielded tells if task gave up the cpu before consuming
1327 * all its available runtime during the last job.
1328 */
1329 int dl_throttled, dl_new, dl_boosted, dl_yielded;
1330
1331 /*
1332 * Bandwidth enforcement timer. Each -deadline task has its
1333 * own bandwidth to be enforced, thus we need one timer per task.
1334 */
1335 struct hrtimer dl_timer;
1336 };
1337
1338 union rcu_special {
1339 struct {
1340 u8 blocked;
1341 u8 need_qs;
1342 u8 exp_need_qs;
1343 u8 pad; /* Otherwise the compiler can store garbage here. */
1344 } b; /* Bits. */
1345 u32 s; /* Set of bits. */
1346 };
1347 struct rcu_node;
1348
1349 enum perf_event_task_context {
1350 perf_invalid_context = -1,
1351 perf_hw_context = 0,
1352 perf_sw_context,
1353 perf_nr_task_contexts,
1354 };
1355
1356 /* Track pages that require TLB flushes */
1357 struct tlbflush_unmap_batch {
1358 /*
1359 * Each bit set is a CPU that potentially has a TLB entry for one of
1360 * the PFNs being flushed. See set_tlb_ubc_flush_pending().
1361 */
1362 struct cpumask cpumask;
1363
1364 /* True if any bit in cpumask is set */
1365 bool flush_required;
1366
1367 /*
1368 * If true then the PTE was dirty when unmapped. The entry must be
1369 * flushed before IO is initiated or a stale TLB entry potentially
1370 * allows an update without redirtying the page.
1371 */
1372 bool writable;
1373 };
1374
1375 struct task_struct {
1376 volatile long state; /* -1 unrunnable, 0 runnable, >0 stopped */
1377 void *stack;
1378 atomic_t usage;
1379 unsigned int flags; /* per process flags, defined below */
1380 unsigned int ptrace;
1381
1382 #ifdef CONFIG_SMP
1383 struct llist_node wake_entry;
1384 int on_cpu;
1385 unsigned int wakee_flips;
1386 unsigned long wakee_flip_decay_ts;
1387 struct task_struct *last_wakee;
1388
1389 int wake_cpu;
1390 #endif
1391 int on_rq;
1392
1393 int prio, static_prio, normal_prio;
1394 unsigned int rt_priority;
1395 const struct sched_class *sched_class;
1396 struct sched_entity se;
1397 struct sched_rt_entity rt;
1398 #ifdef CONFIG_CGROUP_SCHED
1399 struct task_group *sched_task_group;
1400 #endif
1401 struct sched_dl_entity dl;
1402
1403 #ifdef CONFIG_PREEMPT_NOTIFIERS
1404 /* list of struct preempt_notifier: */
1405 struct hlist_head preempt_notifiers;
1406 #endif
1407
1408 #ifdef CONFIG_BLK_DEV_IO_TRACE
1409 unsigned int btrace_seq;
1410 #endif
1411
1412 unsigned int policy;
1413 int nr_cpus_allowed;
1414 cpumask_t cpus_allowed;
1415
1416 #ifdef CONFIG_PREEMPT_RCU
1417 int rcu_read_lock_nesting;
1418 union rcu_special rcu_read_unlock_special;
1419 struct list_head rcu_node_entry;
1420 struct rcu_node *rcu_blocked_node;
1421 #endif /* #ifdef CONFIG_PREEMPT_RCU */
1422 #ifdef CONFIG_TASKS_RCU
1423 unsigned long rcu_tasks_nvcsw;
1424 bool rcu_tasks_holdout;
1425 struct list_head rcu_tasks_holdout_list;
1426 int rcu_tasks_idle_cpu;
1427 #endif /* #ifdef CONFIG_TASKS_RCU */
1428
1429 #ifdef CONFIG_SCHED_INFO
1430 struct sched_info sched_info;
1431 #endif
1432
1433 struct list_head tasks;
1434 #ifdef CONFIG_SMP
1435 struct plist_node pushable_tasks;
1436 struct rb_node pushable_dl_tasks;
1437 #endif
1438
1439 struct mm_struct *mm, *active_mm;
1440 /* per-thread vma caching */
1441 u32 vmacache_seqnum;
1442 struct vm_area_struct *vmacache[VMACACHE_SIZE];
1443 #if defined(SPLIT_RSS_COUNTING)
1444 struct task_rss_stat rss_stat;
1445 #endif
1446 /* task state */
1447 int exit_state;
1448 int exit_code, exit_signal;
1449 int pdeath_signal; /* The signal sent when the parent dies */
1450 unsigned long jobctl; /* JOBCTL_*, siglock protected */
1451
1452 /* Used for emulating ABI behavior of previous Linux versions */
1453 unsigned int personality;
1454
1455 unsigned in_execve:1; /* Tell the LSMs that the process is doing an
1456 * execve */
1457 unsigned in_iowait:1;
1458
1459 /* Revert to default priority/policy when forking */
1460 unsigned sched_reset_on_fork:1;
1461 unsigned sched_contributes_to_load:1;
1462 unsigned sched_migrated:1;
1463
1464 #ifdef CONFIG_MEMCG_KMEM
1465 unsigned memcg_kmem_skip_account:1;
1466 #endif
1467 #ifdef CONFIG_COMPAT_BRK
1468 unsigned brk_randomized:1;
1469 #endif
1470
1471 unsigned long atomic_flags; /* Flags needing atomic access. */
1472
1473 struct restart_block restart_block;
1474
1475 pid_t pid;
1476 pid_t tgid;
1477
1478 #ifdef CONFIG_CC_STACKPROTECTOR
1479 /* Canary value for the -fstack-protector gcc feature */
1480 unsigned long stack_canary;
1481 #endif
1482 /*
1483 * pointers to (original) parent process, youngest child, younger sibling,
1484 * older sibling, respectively. (p->father can be replaced with
1485 * p->real_parent->pid)
1486 */
1487 struct task_struct __rcu *real_parent; /* real parent process */
1488 struct task_struct __rcu *parent; /* recipient of SIGCHLD, wait4() reports */
1489 /*
1490 * children/sibling forms the list of my natural children
1491 */
1492 struct list_head children; /* list of my children */
1493 struct list_head sibling; /* linkage in my parent's children list */
1494 struct task_struct *group_leader; /* threadgroup leader */
1495
1496 /*
1497 * ptraced is the list of tasks this task is using ptrace on.
1498 * This includes both natural children and PTRACE_ATTACH targets.
1499 * p->ptrace_entry is p's link on the p->parent->ptraced list.
1500 */
1501 struct list_head ptraced;
1502 struct list_head ptrace_entry;
1503
1504 /* PID/PID hash table linkage. */
1505 struct pid_link pids[PIDTYPE_MAX];
1506 struct list_head thread_group;
1507 struct list_head thread_node;
1508
1509 struct completion *vfork_done; /* for vfork() */
1510 int __user *set_child_tid; /* CLONE_CHILD_SETTID */
1511 int __user *clear_child_tid; /* CLONE_CHILD_CLEARTID */
1512
1513 cputime_t utime, stime, utimescaled, stimescaled;
1514 cputime_t gtime;
1515 struct prev_cputime prev_cputime;
1516 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
1517 seqlock_t vtime_seqlock;
1518 unsigned long long vtime_snap;
1519 enum {
1520 VTIME_SLEEPING = 0,
1521 VTIME_USER,
1522 VTIME_SYS,
1523 } vtime_snap_whence;
1524 #endif
1525 unsigned long nvcsw, nivcsw; /* context switch counts */
1526 u64 start_time; /* monotonic time in nsec */
1527 u64 real_start_time; /* boot based time in nsec */
1528 /* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
1529 unsigned long min_flt, maj_flt;
1530
1531 struct task_cputime cputime_expires;
1532 struct list_head cpu_timers[3];
1533
1534 /* process credentials */
1535 const struct cred __rcu *real_cred; /* objective and real subjective task
1536 * credentials (COW) */
1537 const struct cred __rcu *cred; /* effective (overridable) subjective task
1538 * credentials (COW) */
1539 char comm[TASK_COMM_LEN]; /* executable name excluding path
1540 - access with [gs]et_task_comm (which lock
1541 it with task_lock())
1542 - initialized normally by setup_new_exec */
1543 /* file system info */
1544 struct nameidata *nameidata;
1545 #ifdef CONFIG_SYSVIPC
1546 /* ipc stuff */
1547 struct sysv_sem sysvsem;
1548 struct sysv_shm sysvshm;
1549 #endif
1550 #ifdef CONFIG_DETECT_HUNG_TASK
1551 /* hung task detection */
1552 unsigned long last_switch_count;
1553 #endif
1554 /* filesystem information */
1555 struct fs_struct *fs;
1556 /* open file information */
1557 struct files_struct *files;
1558 /* namespaces */
1559 struct nsproxy *nsproxy;
1560 /* signal handlers */
1561 struct signal_struct *signal;
1562 struct sighand_struct *sighand;
1563
1564 sigset_t blocked, real_blocked;
1565 sigset_t saved_sigmask; /* restored if set_restore_sigmask() was used */
1566 struct sigpending pending;
1567
1568 unsigned long sas_ss_sp;
1569 size_t sas_ss_size;
1570 int (*notifier)(void *priv);
1571 void *notifier_data;
1572 sigset_t *notifier_mask;
1573 struct callback_head *task_works;
1574
1575 struct audit_context *audit_context;
1576 #ifdef CONFIG_AUDITSYSCALL
1577 kuid_t loginuid;
1578 unsigned int sessionid;
1579 #endif
1580 struct seccomp seccomp;
1581
1582 /* Thread group tracking */
1583 u32 parent_exec_id;
1584 u32 self_exec_id;
1585 /* Protection of (de-)allocation: mm, files, fs, tty, keyrings, mems_allowed,
1586 * mempolicy */
1587 spinlock_t alloc_lock;
1588
1589 /* Protection of the PI data structures: */
1590 raw_spinlock_t pi_lock;
1591
1592 struct wake_q_node wake_q;
1593
1594 #ifdef CONFIG_RT_MUTEXES
1595 /* PI waiters blocked on a rt_mutex held by this task */
1596 struct rb_root pi_waiters;
1597 struct rb_node *pi_waiters_leftmost;
1598 /* Deadlock detection and priority inheritance handling */
1599 struct rt_mutex_waiter *pi_blocked_on;
1600 #endif
1601
1602 #ifdef CONFIG_DEBUG_MUTEXES
1603 /* mutex deadlock detection */
1604 struct mutex_waiter *blocked_on;
1605 #endif
1606 #ifdef CONFIG_TRACE_IRQFLAGS
1607 unsigned int irq_events;
1608 unsigned long hardirq_enable_ip;
1609 unsigned long hardirq_disable_ip;
1610 unsigned int hardirq_enable_event;
1611 unsigned int hardirq_disable_event;
1612 int hardirqs_enabled;
1613 int hardirq_context;
1614 unsigned long softirq_disable_ip;
1615 unsigned long softirq_enable_ip;
1616 unsigned int softirq_disable_event;
1617 unsigned int softirq_enable_event;
1618 int softirqs_enabled;
1619 int softirq_context;
1620 #endif
1621 #ifdef CONFIG_LOCKDEP
1622 # define MAX_LOCK_DEPTH 48UL
1623 u64 curr_chain_key;
1624 int lockdep_depth;
1625 unsigned int lockdep_recursion;
1626 struct held_lock held_locks[MAX_LOCK_DEPTH];
1627 gfp_t lockdep_reclaim_gfp;
1628 #endif
1629
1630 /* journalling filesystem info */
1631 void *journal_info;
1632
1633 /* stacked block device info */
1634 struct bio_list *bio_list;
1635
1636 #ifdef CONFIG_BLOCK
1637 /* stack plugging */
1638 struct blk_plug *plug;
1639 #endif
1640
1641 /* VM state */
1642 struct reclaim_state *reclaim_state;
1643
1644 struct backing_dev_info *backing_dev_info;
1645
1646 struct io_context *io_context;
1647
1648 unsigned long ptrace_message;
1649 siginfo_t *last_siginfo; /* For ptrace use. */
1650 struct task_io_accounting ioac;
1651 #if defined(CONFIG_TASK_XACCT)
1652 u64 acct_rss_mem1; /* accumulated rss usage */
1653 u64 acct_vm_mem1; /* accumulated virtual memory usage */
1654 cputime_t acct_timexpd; /* stime + utime since last update */
1655 #endif
1656 #ifdef CONFIG_CPUSETS
1657 nodemask_t mems_allowed; /* Protected by alloc_lock */
1658 seqcount_t mems_allowed_seq; /* Seqence no to catch updates */
1659 int cpuset_mem_spread_rotor;
1660 int cpuset_slab_spread_rotor;
1661 #endif
1662 #ifdef CONFIG_CGROUPS
1663 /* Control Group info protected by css_set_lock */
1664 struct css_set __rcu *cgroups;
1665 /* cg_list protected by css_set_lock and tsk->alloc_lock */
1666 struct list_head cg_list;
1667 #endif
1668 #ifdef CONFIG_FUTEX
1669 struct robust_list_head __user *robust_list;
1670 #ifdef CONFIG_COMPAT
1671 struct compat_robust_list_head __user *compat_robust_list;
1672 #endif
1673 struct list_head pi_state_list;
1674 struct futex_pi_state *pi_state_cache;
1675 #endif
1676 #ifdef CONFIG_PERF_EVENTS
1677 struct perf_event_context *perf_event_ctxp[perf_nr_task_contexts];
1678 struct mutex perf_event_mutex;
1679 struct list_head perf_event_list;
1680 #endif
1681 #ifdef CONFIG_DEBUG_PREEMPT
1682 unsigned long preempt_disable_ip;
1683 #endif
1684 #ifdef CONFIG_NUMA
1685 struct mempolicy *mempolicy; /* Protected by alloc_lock */
1686 short il_next;
1687 short pref_node_fork;
1688 #endif
1689 #ifdef CONFIG_NUMA_BALANCING
1690 int numa_scan_seq;
1691 unsigned int numa_scan_period;
1692 unsigned int numa_scan_period_max;
1693 int numa_preferred_nid;
1694 unsigned long numa_migrate_retry;
1695 u64 node_stamp; /* migration stamp */
1696 u64 last_task_numa_placement;
1697 u64 last_sum_exec_runtime;
1698 struct callback_head numa_work;
1699
1700 struct list_head numa_entry;
1701 struct numa_group *numa_group;
1702
1703 /*
1704 * numa_faults is an array split into four regions:
1705 * faults_memory, faults_cpu, faults_memory_buffer, faults_cpu_buffer
1706 * in this precise order.
1707 *
1708 * faults_memory: Exponential decaying average of faults on a per-node
1709 * basis. Scheduling placement decisions are made based on these
1710 * counts. The values remain static for the duration of a PTE scan.
1711 * faults_cpu: Track the nodes the process was running on when a NUMA
1712 * hinting fault was incurred.
1713 * faults_memory_buffer and faults_cpu_buffer: Record faults per node
1714 * during the current scan window. When the scan completes, the counts
1715 * in faults_memory and faults_cpu decay and these values are copied.
1716 */
1717 unsigned long *numa_faults;
1718 unsigned long total_numa_faults;
1719
1720 /*
1721 * numa_faults_locality tracks if faults recorded during the last
1722 * scan window were remote/local or failed to migrate. The task scan
1723 * period is adapted based on the locality of the faults with different
1724 * weights depending on whether they were shared or private faults
1725 */
1726 unsigned long numa_faults_locality[3];
1727
1728 unsigned long numa_pages_migrated;
1729 #endif /* CONFIG_NUMA_BALANCING */
1730
1731 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
1732 struct tlbflush_unmap_batch tlb_ubc;
1733 #endif
1734
1735 struct rcu_head rcu;
1736
1737 /*
1738 * cache last used pipe for splice
1739 */
1740 struct pipe_inode_info *splice_pipe;
1741
1742 struct page_frag task_frag;
1743
1744 #ifdef CONFIG_TASK_DELAY_ACCT
1745 struct task_delay_info *delays;
1746 #endif
1747 #ifdef CONFIG_FAULT_INJECTION
1748 int make_it_fail;
1749 #endif
1750 /*
1751 * when (nr_dirtied >= nr_dirtied_pause), it's time to call
1752 * balance_dirty_pages() for some dirty throttling pause
1753 */
1754 int nr_dirtied;
1755 int nr_dirtied_pause;
1756 unsigned long dirty_paused_when; /* start of a write-and-pause period */
1757
1758 #ifdef CONFIG_LATENCYTOP
1759 int latency_record_count;
1760 struct latency_record latency_record[LT_SAVECOUNT];
1761 #endif
1762 /*
1763 * time slack values; these are used to round up poll() and
1764 * select() etc timeout values. These are in nanoseconds.
1765 */
1766 unsigned long timer_slack_ns;
1767 unsigned long default_timer_slack_ns;
1768
1769 #ifdef CONFIG_KASAN
1770 unsigned int kasan_depth;
1771 #endif
1772 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
1773 /* Index of current stored address in ret_stack */
1774 int curr_ret_stack;
1775 /* Stack of return addresses for return function tracing */
1776 struct ftrace_ret_stack *ret_stack;
1777 /* time stamp for last schedule */
1778 unsigned long long ftrace_timestamp;
1779 /*
1780 * Number of functions that haven't been traced
1781 * because of depth overrun.
1782 */
1783 atomic_t trace_overrun;
1784 /* Pause for the tracing */
1785 atomic_t tracing_graph_pause;
1786 #endif
1787 #ifdef CONFIG_TRACING
1788 /* state flags for use by tracers */
1789 unsigned long trace;
1790 /* bitmask and counter of trace recursion */
1791 unsigned long trace_recursion;
1792 #endif /* CONFIG_TRACING */
1793 #ifdef CONFIG_MEMCG
1794 struct memcg_oom_info {
1795 struct mem_cgroup *memcg;
1796 gfp_t gfp_mask;
1797 int order;
1798 unsigned int may_oom:1;
1799 } memcg_oom;
1800 #endif
1801 #ifdef CONFIG_UPROBES
1802 struct uprobe_task *utask;
1803 #endif
1804 #if defined(CONFIG_BCACHE) || defined(CONFIG_BCACHE_MODULE)
1805 unsigned int sequential_io;
1806 unsigned int sequential_io_avg;
1807 #endif
1808 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP
1809 unsigned long task_state_change;
1810 #endif
1811 int pagefault_disabled;
1812 /* CPU-specific state of this task */
1813 struct thread_struct thread;
1814 /*
1815 * WARNING: on x86, 'thread_struct' contains a variable-sized
1816 * structure. It *MUST* be at the end of 'task_struct'.
1817 *
1818 * Do not put anything below here!
1819 */
1820 };
1821
1822 #ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT
1823 extern int arch_task_struct_size __read_mostly;
1824 #else
1825 # define arch_task_struct_size (sizeof(struct task_struct))
1826 #endif
1827
1828 /* Future-safe accessor for struct task_struct's cpus_allowed. */
1829 #define tsk_cpus_allowed(tsk) (&(tsk)->cpus_allowed)
1830
1831 #define TNF_MIGRATED 0x01
1832 #define TNF_NO_GROUP 0x02
1833 #define TNF_SHARED 0x04
1834 #define TNF_FAULT_LOCAL 0x08
1835 #define TNF_MIGRATE_FAIL 0x10
1836
1837 #ifdef CONFIG_NUMA_BALANCING
1838 extern void task_numa_fault(int last_node, int node, int pages, int flags);
1839 extern pid_t task_numa_group_id(struct task_struct *p);
1840 extern void set_numabalancing_state(bool enabled);
1841 extern void task_numa_free(struct task_struct *p);
1842 extern bool should_numa_migrate_memory(struct task_struct *p, struct page *page,
1843 int src_nid, int dst_cpu);
1844 #else
1845 static inline void task_numa_fault(int last_node, int node, int pages,
1846 int flags)
1847 {
1848 }
1849 static inline pid_t task_numa_group_id(struct task_struct *p)
1850 {
1851 return 0;
1852 }
1853 static inline void set_numabalancing_state(bool enabled)
1854 {
1855 }
1856 static inline void task_numa_free(struct task_struct *p)
1857 {
1858 }
1859 static inline bool should_numa_migrate_memory(struct task_struct *p,
1860 struct page *page, int src_nid, int dst_cpu)
1861 {
1862 return true;
1863 }
1864 #endif
1865
1866 static inline struct pid *task_pid(struct task_struct *task)
1867 {
1868 return task->pids[PIDTYPE_PID].pid;
1869 }
1870
1871 static inline struct pid *task_tgid(struct task_struct *task)
1872 {
1873 return task->group_leader->pids[PIDTYPE_PID].pid;
1874 }
1875
1876 /*
1877 * Without tasklist or rcu lock it is not safe to dereference
1878 * the result of task_pgrp/task_session even if task == current,
1879 * we can race with another thread doing sys_setsid/sys_setpgid.
1880 */
1881 static inline struct pid *task_pgrp(struct task_struct *task)
1882 {
1883 return task->group_leader->pids[PIDTYPE_PGID].pid;
1884 }
1885
1886 static inline struct pid *task_session(struct task_struct *task)
1887 {
1888 return task->group_leader->pids[PIDTYPE_SID].pid;
1889 }
1890
1891 struct pid_namespace;
1892
1893 /*
1894 * the helpers to get the task's different pids as they are seen
1895 * from various namespaces
1896 *
1897 * task_xid_nr() : global id, i.e. the id seen from the init namespace;
1898 * task_xid_vnr() : virtual id, i.e. the id seen from the pid namespace of
1899 * current.
1900 * task_xid_nr_ns() : id seen from the ns specified;
1901 *
1902 * set_task_vxid() : assigns a virtual id to a task;
1903 *
1904 * see also pid_nr() etc in include/linux/pid.h
1905 */
1906 pid_t __task_pid_nr_ns(struct task_struct *task, enum pid_type type,
1907 struct pid_namespace *ns);
1908
1909 static inline pid_t task_pid_nr(struct task_struct *tsk)
1910 {
1911 return tsk->pid;
1912 }
1913
1914 static inline pid_t task_pid_nr_ns(struct task_struct *tsk,
1915 struct pid_namespace *ns)
1916 {
1917 return __task_pid_nr_ns(tsk, PIDTYPE_PID, ns);
1918 }
1919
1920 static inline pid_t task_pid_vnr(struct task_struct *tsk)
1921 {
1922 return __task_pid_nr_ns(tsk, PIDTYPE_PID, NULL);
1923 }
1924
1925
1926 static inline pid_t task_tgid_nr(struct task_struct *tsk)
1927 {
1928 return tsk->tgid;
1929 }
1930
1931 pid_t task_tgid_nr_ns(struct task_struct *tsk, struct pid_namespace *ns);
1932
1933 static inline pid_t task_tgid_vnr(struct task_struct *tsk)
1934 {
1935 return pid_vnr(task_tgid(tsk));
1936 }
1937
1938
1939 static inline int pid_alive(const struct task_struct *p);
1940 static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_namespace *ns)
1941 {
1942 pid_t pid = 0;
1943
1944 rcu_read_lock();
1945 if (pid_alive(tsk))
1946 pid = task_tgid_nr_ns(rcu_dereference(tsk->real_parent), ns);
1947 rcu_read_unlock();
1948
1949 return pid;
1950 }
1951
1952 static inline pid_t task_ppid_nr(const struct task_struct *tsk)
1953 {
1954 return task_ppid_nr_ns(tsk, &init_pid_ns);
1955 }
1956
1957 static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk,
1958 struct pid_namespace *ns)
1959 {
1960 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, ns);
1961 }
1962
1963 static inline pid_t task_pgrp_vnr(struct task_struct *tsk)
1964 {
1965 return __task_pid_nr_ns(tsk, PIDTYPE_PGID, NULL);
1966 }
1967
1968
1969 static inline pid_t task_session_nr_ns(struct task_struct *tsk,
1970 struct pid_namespace *ns)
1971 {
1972 return __task_pid_nr_ns(tsk, PIDTYPE_SID, ns);
1973 }
1974
1975 static inline pid_t task_session_vnr(struct task_struct *tsk)
1976 {
1977 return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL);
1978 }
1979
1980 /* obsolete, do not use */
1981 static inline pid_t task_pgrp_nr(struct task_struct *tsk)
1982 {
1983 return task_pgrp_nr_ns(tsk, &init_pid_ns);
1984 }
1985
1986 /**
1987 * pid_alive - check that a task structure is not stale
1988 * @p: Task structure to be checked.
1989 *
1990 * Test if a process is not yet dead (at most zombie state)
1991 * If pid_alive fails, then pointers within the task structure
1992 * can be stale and must not be dereferenced.
1993 *
1994 * Return: 1 if the process is alive. 0 otherwise.
1995 */
1996 static inline int pid_alive(const struct task_struct *p)
1997 {
1998 return p->pids[PIDTYPE_PID].pid != NULL;
1999 }
2000
2001 /**
2002 * is_global_init - check if a task structure is init
2003 * @tsk: Task structure to be checked.
2004 *
2005 * Check if a task structure is the first user space task the kernel created.
2006 *
2007 * Return: 1 if the task structure is init. 0 otherwise.
2008 */
2009 static inline int is_global_init(struct task_struct *tsk)
2010 {
2011 return tsk->pid == 1;
2012 }
2013
2014 extern struct pid *cad_pid;
2015
2016 extern void free_task(struct task_struct *tsk);
2017 #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0)
2018
2019 extern void __put_task_struct(struct task_struct *t);
2020
2021 static inline void put_task_struct(struct task_struct *t)
2022 {
2023 if (atomic_dec_and_test(&t->usage))
2024 __put_task_struct(t);
2025 }
2026
2027 #ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
2028 extern void task_cputime(struct task_struct *t,
2029 cputime_t *utime, cputime_t *stime);
2030 extern void task_cputime_scaled(struct task_struct *t,
2031 cputime_t *utimescaled, cputime_t *stimescaled);
2032 extern cputime_t task_gtime(struct task_struct *t);
2033 #else
2034 static inline void task_cputime(struct task_struct *t,
2035 cputime_t *utime, cputime_t *stime)
2036 {
2037 if (utime)
2038 *utime = t->utime;
2039 if (stime)
2040 *stime = t->stime;
2041 }
2042
2043 static inline void task_cputime_scaled(struct task_struct *t,
2044 cputime_t *utimescaled,
2045 cputime_t *stimescaled)
2046 {
2047 if (utimescaled)
2048 *utimescaled = t->utimescaled;
2049 if (stimescaled)
2050 *stimescaled = t->stimescaled;
2051 }
2052
2053 static inline cputime_t task_gtime(struct task_struct *t)
2054 {
2055 return t->gtime;
2056 }
2057 #endif
2058 extern void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
2059 extern void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st);
2060
2061 /*
2062 * Per process flags
2063 */
2064 #define PF_EXITING 0x00000004 /* getting shut down */
2065 #define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */
2066 #define PF_VCPU 0x00000010 /* I'm a virtual CPU */
2067 #define PF_WQ_WORKER 0x00000020 /* I'm a workqueue worker */
2068 #define PF_FORKNOEXEC 0x00000040 /* forked but didn't exec */
2069 #define PF_MCE_PROCESS 0x00000080 /* process policy on mce errors */
2070 #define PF_SUPERPRIV 0x00000100 /* used super-user privileges */
2071 #define PF_DUMPCORE 0x00000200 /* dumped core */
2072 #define PF_SIGNALED 0x00000400 /* killed by a signal */
2073 #define PF_MEMALLOC 0x00000800 /* Allocating memory */
2074 #define PF_NPROC_EXCEEDED 0x00001000 /* set_user noticed that RLIMIT_NPROC was exceeded */
2075 #define PF_USED_MATH 0x00002000 /* if unset the fpu must be initialized before use */
2076 #define PF_USED_ASYNC 0x00004000 /* used async_schedule*(), used by module init */
2077 #define PF_NOFREEZE 0x00008000 /* this thread should not be frozen */
2078 #define PF_FROZEN 0x00010000 /* frozen for system suspend */
2079 #define PF_FSTRANS 0x00020000 /* inside a filesystem transaction */
2080 #define PF_KSWAPD 0x00040000 /* I am kswapd */
2081 #define PF_MEMALLOC_NOIO 0x00080000 /* Allocating memory without IO involved */
2082 #define PF_LESS_THROTTLE 0x00100000 /* Throttle me less: I clean memory */
2083 #define PF_KTHREAD 0x00200000 /* I am a kernel thread */
2084 #define PF_RANDOMIZE 0x00400000 /* randomize virtual address space */
2085 #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */
2086 #define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */
2087 #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */
2088 #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */
2089 #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */
2090 #define PF_SUSPEND_TASK 0x80000000 /* this thread called freeze_processes and should not be frozen */
2091
2092 /*
2093 * Only the _current_ task can read/write to tsk->flags, but other
2094 * tasks can access tsk->flags in readonly mode for example
2095 * with tsk_used_math (like during threaded core dumping).
2096 * There is however an exception to this rule during ptrace
2097 * or during fork: the ptracer task is allowed to write to the
2098 * child->flags of its traced child (same goes for fork, the parent
2099 * can write to the child->flags), because we're guaranteed the
2100 * child is not running and in turn not changing child->flags
2101 * at the same time the parent does it.
2102 */
2103 #define clear_stopped_child_used_math(child) do { (child)->flags &= ~PF_USED_MATH; } while (0)
2104 #define set_stopped_child_used_math(child) do { (child)->flags |= PF_USED_MATH; } while (0)
2105 #define clear_used_math() clear_stopped_child_used_math(current)
2106 #define set_used_math() set_stopped_child_used_math(current)
2107 #define conditional_stopped_child_used_math(condition, child) \
2108 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= (condition) ? PF_USED_MATH : 0; } while (0)
2109 #define conditional_used_math(condition) \
2110 conditional_stopped_child_used_math(condition, current)
2111 #define copy_to_stopped_child_used_math(child) \
2112 do { (child)->flags &= ~PF_USED_MATH, (child)->flags |= current->flags & PF_USED_MATH; } while (0)
2113 /* NOTE: this will return 0 or PF_USED_MATH, it will never return 1 */
2114 #define tsk_used_math(p) ((p)->flags & PF_USED_MATH)
2115 #define used_math() tsk_used_math(current)
2116
2117 /* __GFP_IO isn't allowed if PF_MEMALLOC_NOIO is set in current->flags
2118 * __GFP_FS is also cleared as it implies __GFP_IO.
2119 */
2120 static inline gfp_t memalloc_noio_flags(gfp_t flags)
2121 {
2122 if (unlikely(current->flags & PF_MEMALLOC_NOIO))
2123 flags &= ~(__GFP_IO | __GFP_FS);
2124 return flags;
2125 }
2126
2127 static inline unsigned int memalloc_noio_save(void)
2128 {
2129 unsigned int flags = current->flags & PF_MEMALLOC_NOIO;
2130 current->flags |= PF_MEMALLOC_NOIO;
2131 return flags;
2132 }
2133
2134 static inline void memalloc_noio_restore(unsigned int flags)
2135 {
2136 current->flags = (current->flags & ~PF_MEMALLOC_NOIO) | flags;
2137 }
2138
2139 /* Per-process atomic flags. */
2140 #define PFA_NO_NEW_PRIVS 0 /* May not gain new privileges. */
2141 #define PFA_SPREAD_PAGE 1 /* Spread page cache over cpuset */
2142 #define PFA_SPREAD_SLAB 2 /* Spread some slab caches over cpuset */
2143
2144
2145 #define TASK_PFA_TEST(name, func) \
2146 static inline bool task_##func(struct task_struct *p) \
2147 { return test_bit(PFA_##name, &p->atomic_flags); }
2148 #define TASK_PFA_SET(name, func) \
2149 static inline void task_set_##func(struct task_struct *p) \
2150 { set_bit(PFA_##name, &p->atomic_flags); }
2151 #define TASK_PFA_CLEAR(name, func) \
2152 static inline void task_clear_##func(struct task_struct *p) \
2153 { clear_bit(PFA_##name, &p->atomic_flags); }
2154
2155 TASK_PFA_TEST(NO_NEW_PRIVS, no_new_privs)
2156 TASK_PFA_SET(NO_NEW_PRIVS, no_new_privs)
2157
2158 TASK_PFA_TEST(SPREAD_PAGE, spread_page)
2159 TASK_PFA_SET(SPREAD_PAGE, spread_page)
2160 TASK_PFA_CLEAR(SPREAD_PAGE, spread_page)
2161
2162 TASK_PFA_TEST(SPREAD_SLAB, spread_slab)
2163 TASK_PFA_SET(SPREAD_SLAB, spread_slab)
2164 TASK_PFA_CLEAR(SPREAD_SLAB, spread_slab)
2165
2166 /*
2167 * task->jobctl flags
2168 */
2169 #define JOBCTL_STOP_SIGMASK 0xffff /* signr of the last group stop */
2170
2171 #define JOBCTL_STOP_DEQUEUED_BIT 16 /* stop signal dequeued */
2172 #define JOBCTL_STOP_PENDING_BIT 17 /* task should stop for group stop */
2173 #define JOBCTL_STOP_CONSUME_BIT 18 /* consume group stop count */
2174 #define JOBCTL_TRAP_STOP_BIT 19 /* trap for STOP */
2175 #define JOBCTL_TRAP_NOTIFY_BIT 20 /* trap for NOTIFY */
2176 #define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */
2177 #define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */
2178
2179 #define JOBCTL_STOP_DEQUEUED (1UL << JOBCTL_STOP_DEQUEUED_BIT)
2180 #define JOBCTL_STOP_PENDING (1UL << JOBCTL_STOP_PENDING_BIT)
2181 #define JOBCTL_STOP_CONSUME (1UL << JOBCTL_STOP_CONSUME_BIT)
2182 #define JOBCTL_TRAP_STOP (1UL << JOBCTL_TRAP_STOP_BIT)
2183 #define JOBCTL_TRAP_NOTIFY (1UL << JOBCTL_TRAP_NOTIFY_BIT)
2184 #define JOBCTL_TRAPPING (1UL << JOBCTL_TRAPPING_BIT)
2185 #define JOBCTL_LISTENING (1UL << JOBCTL_LISTENING_BIT)
2186
2187 #define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY)
2188 #define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK)
2189
2190 extern bool task_set_jobctl_pending(struct task_struct *task,
2191 unsigned long mask);
2192 extern void task_clear_jobctl_trapping(struct task_struct *task);
2193 extern void task_clear_jobctl_pending(struct task_struct *task,
2194 unsigned long mask);
2195
2196 static inline void rcu_copy_process(struct task_struct *p)
2197 {
2198 #ifdef CONFIG_PREEMPT_RCU
2199 p->rcu_read_lock_nesting = 0;
2200 p->rcu_read_unlock_special.s = 0;
2201 p->rcu_blocked_node = NULL;
2202 INIT_LIST_HEAD(&p->rcu_node_entry);
2203 #endif /* #ifdef CONFIG_PREEMPT_RCU */
2204 #ifdef CONFIG_TASKS_RCU
2205 p->rcu_tasks_holdout = false;
2206 INIT_LIST_HEAD(&p->rcu_tasks_holdout_list);
2207 p->rcu_tasks_idle_cpu = -1;
2208 #endif /* #ifdef CONFIG_TASKS_RCU */
2209 }
2210
2211 static inline void tsk_restore_flags(struct task_struct *task,
2212 unsigned long orig_flags, unsigned long flags)
2213 {
2214 task->flags &= ~flags;
2215 task->flags |= orig_flags & flags;
2216 }
2217
2218 extern int cpuset_cpumask_can_shrink(const struct cpumask *cur,
2219 const struct cpumask *trial);
2220 extern int task_can_attach(struct task_struct *p,
2221 const struct cpumask *cs_cpus_allowed);
2222 #ifdef CONFIG_SMP
2223 extern void do_set_cpus_allowed(struct task_struct *p,
2224 const struct cpumask *new_mask);
2225
2226 extern int set_cpus_allowed_ptr(struct task_struct *p,
2227 const struct cpumask *new_mask);
2228 #else
2229 static inline void do_set_cpus_allowed(struct task_struct *p,
2230 const struct cpumask *new_mask)
2231 {
2232 }
2233 static inline int set_cpus_allowed_ptr(struct task_struct *p,
2234 const struct cpumask *new_mask)
2235 {
2236 if (!cpumask_test_cpu(0, new_mask))
2237 return -EINVAL;
2238 return 0;
2239 }
2240 #endif
2241
2242 #ifdef CONFIG_NO_HZ_COMMON
2243 void calc_load_enter_idle(void);
2244 void calc_load_exit_idle(void);
2245 #else
2246 static inline void calc_load_enter_idle(void) { }
2247 static inline void calc_load_exit_idle(void) { }
2248 #endif /* CONFIG_NO_HZ_COMMON */
2249
2250 /*
2251 * Do not use outside of architecture code which knows its limitations.
2252 *
2253 * sched_clock() has no promise of monotonicity or bounded drift between
2254 * CPUs, use (which you should not) requires disabling IRQs.
2255 *
2256 * Please use one of the three interfaces below.
2257 */
2258 extern unsigned long long notrace sched_clock(void);
2259 /*
2260 * See the comment in kernel/sched/clock.c
2261 */
2262 extern u64 cpu_clock(int cpu);
2263 extern u64 local_clock(void);
2264 extern u64 running_clock(void);
2265 extern u64 sched_clock_cpu(int cpu);
2266
2267
2268 extern void sched_clock_init(void);
2269
2270 #ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
2271 static inline void sched_clock_tick(void)
2272 {
2273 }
2274
2275 static inline void sched_clock_idle_sleep_event(void)
2276 {
2277 }
2278
2279 static inline void sched_clock_idle_wakeup_event(u64 delta_ns)
2280 {
2281 }
2282 #else
2283 /*
2284 * Architectures can set this to 1 if they have specified
2285 * CONFIG_HAVE_UNSTABLE_SCHED_CLOCK in their arch Kconfig,
2286 * but then during bootup it turns out that sched_clock()
2287 * is reliable after all:
2288 */
2289 extern int sched_clock_stable(void);
2290 extern void set_sched_clock_stable(void);
2291 extern void clear_sched_clock_stable(void);
2292
2293 extern void sched_clock_tick(void);
2294 extern void sched_clock_idle_sleep_event(void);
2295 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2296 #endif
2297
2298 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2299 /*
2300 * An i/f to runtime opt-in for irq time accounting based off of sched_clock.
2301 * The reason for this explicit opt-in is not to have perf penalty with
2302 * slow sched_clocks.
2303 */
2304 extern void enable_sched_clock_irqtime(void);
2305 extern void disable_sched_clock_irqtime(void);
2306 #else
2307 static inline void enable_sched_clock_irqtime(void) {}
2308 static inline void disable_sched_clock_irqtime(void) {}
2309 #endif
2310
2311 extern unsigned long long
2312 task_sched_runtime(struct task_struct *task);
2313
2314 /* sched_exec is called by processes performing an exec */
2315 #ifdef CONFIG_SMP
2316 extern void sched_exec(void);
2317 #else
2318 #define sched_exec() {}
2319 #endif
2320
2321 extern void sched_clock_idle_sleep_event(void);
2322 extern void sched_clock_idle_wakeup_event(u64 delta_ns);
2323
2324 #ifdef CONFIG_HOTPLUG_CPU
2325 extern void idle_task_exit(void);
2326 #else
2327 static inline void idle_task_exit(void) {}
2328 #endif
2329
2330 #if defined(CONFIG_NO_HZ_COMMON) && defined(CONFIG_SMP)
2331 extern void wake_up_nohz_cpu(int cpu);
2332 #else
2333 static inline void wake_up_nohz_cpu(int cpu) { }
2334 #endif
2335
2336 #ifdef CONFIG_NO_HZ_FULL
2337 extern bool sched_can_stop_tick(void);
2338 extern u64 scheduler_tick_max_deferment(void);
2339 #else
2340 static inline bool sched_can_stop_tick(void) { return false; }
2341 #endif
2342
2343 #ifdef CONFIG_SCHED_AUTOGROUP
2344 extern void sched_autogroup_create_attach(struct task_struct *p);
2345 extern void sched_autogroup_detach(struct task_struct *p);
2346 extern void sched_autogroup_fork(struct signal_struct *sig);
2347 extern void sched_autogroup_exit(struct signal_struct *sig);
2348 #ifdef CONFIG_PROC_FS
2349 extern void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m);
2350 extern int proc_sched_autogroup_set_nice(struct task_struct *p, int nice);
2351 #endif
2352 #else
2353 static inline void sched_autogroup_create_attach(struct task_struct *p) { }
2354 static inline void sched_autogroup_detach(struct task_struct *p) { }
2355 static inline void sched_autogroup_fork(struct signal_struct *sig) { }
2356 static inline void sched_autogroup_exit(struct signal_struct *sig) { }
2357 #endif
2358
2359 extern int yield_to(struct task_struct *p, bool preempt);
2360 extern void set_user_nice(struct task_struct *p, long nice);
2361 extern int task_prio(const struct task_struct *p);
2362 /**
2363 * task_nice - return the nice value of a given task.
2364 * @p: the task in question.
2365 *
2366 * Return: The nice value [ -20 ... 0 ... 19 ].
2367 */
2368 static inline int task_nice(const struct task_struct *p)
2369 {
2370 return PRIO_TO_NICE((p)->static_prio);
2371 }
2372 extern int can_nice(const struct task_struct *p, const int nice);
2373 extern int task_curr(const struct task_struct *p);
2374 extern int idle_cpu(int cpu);
2375 extern int sched_setscheduler(struct task_struct *, int,
2376 const struct sched_param *);
2377 extern int sched_setscheduler_nocheck(struct task_struct *, int,
2378 const struct sched_param *);
2379 extern int sched_setattr(struct task_struct *,
2380 const struct sched_attr *);
2381 extern struct task_struct *idle_task(int cpu);
2382 /**
2383 * is_idle_task - is the specified task an idle task?
2384 * @p: the task in question.
2385 *
2386 * Return: 1 if @p is an idle task. 0 otherwise.
2387 */
2388 static inline bool is_idle_task(const struct task_struct *p)
2389 {
2390 return p->pid == 0;
2391 }
2392 extern struct task_struct *curr_task(int cpu);
2393 extern void set_curr_task(int cpu, struct task_struct *p);
2394
2395 void yield(void);
2396
2397 union thread_union {
2398 struct thread_info thread_info;
2399 unsigned long stack[THREAD_SIZE/sizeof(long)];
2400 };
2401
2402 #ifndef __HAVE_ARCH_KSTACK_END
2403 static inline int kstack_end(void *addr)
2404 {
2405 /* Reliable end of stack detection:
2406 * Some APM bios versions misalign the stack
2407 */
2408 return !(((unsigned long)addr+sizeof(void*)-1) & (THREAD_SIZE-sizeof(void*)));
2409 }
2410 #endif
2411
2412 extern union thread_union init_thread_union;
2413 extern struct task_struct init_task;
2414
2415 extern struct mm_struct init_mm;
2416
2417 extern struct pid_namespace init_pid_ns;
2418
2419 /*
2420 * find a task by one of its numerical ids
2421 *
2422 * find_task_by_pid_ns():
2423 * finds a task by its pid in the specified namespace
2424 * find_task_by_vpid():
2425 * finds a task by its virtual pid
2426 *
2427 * see also find_vpid() etc in include/linux/pid.h
2428 */
2429
2430 extern struct task_struct *find_task_by_vpid(pid_t nr);
2431 extern struct task_struct *find_task_by_pid_ns(pid_t nr,
2432 struct pid_namespace *ns);
2433
2434 /* per-UID process charging. */
2435 extern struct user_struct * alloc_uid(kuid_t);
2436 static inline struct user_struct *get_uid(struct user_struct *u)
2437 {
2438 atomic_inc(&u->__count);
2439 return u;
2440 }
2441 extern void free_uid(struct user_struct *);
2442
2443 #include <asm/current.h>
2444
2445 extern void xtime_update(unsigned long ticks);
2446
2447 extern int wake_up_state(struct task_struct *tsk, unsigned int state);
2448 extern int wake_up_process(struct task_struct *tsk);
2449 extern void wake_up_new_task(struct task_struct *tsk);
2450 #ifdef CONFIG_SMP
2451 extern void kick_process(struct task_struct *tsk);
2452 #else
2453 static inline void kick_process(struct task_struct *tsk) { }
2454 #endif
2455 extern int sched_fork(unsigned long clone_flags, struct task_struct *p);
2456 extern void sched_dead(struct task_struct *p);
2457
2458 extern void proc_caches_init(void);
2459 extern void flush_signals(struct task_struct *);
2460 extern void ignore_signals(struct task_struct *);
2461 extern void flush_signal_handlers(struct task_struct *, int force_default);
2462 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info);
2463
2464 static inline int dequeue_signal_lock(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
2465 {
2466 unsigned long flags;
2467 int ret;
2468
2469 spin_lock_irqsave(&tsk->sighand->siglock, flags);
2470 ret = dequeue_signal(tsk, mask, info);
2471 spin_unlock_irqrestore(&tsk->sighand->siglock, flags);
2472
2473 return ret;
2474 }
2475
2476 extern void block_all_signals(int (*notifier)(void *priv), void *priv,
2477 sigset_t *mask);
2478 extern void unblock_all_signals(void);
2479 extern void release_task(struct task_struct * p);
2480 extern int send_sig_info(int, struct siginfo *, struct task_struct *);
2481 extern int force_sigsegv(int, struct task_struct *);
2482 extern int force_sig_info(int, struct siginfo *, struct task_struct *);
2483 extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp);
2484 extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid);
2485 extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *,
2486 const struct cred *, u32);
2487 extern int kill_pgrp(struct pid *pid, int sig, int priv);
2488 extern int kill_pid(struct pid *pid, int sig, int priv);
2489 extern int kill_proc_info(int, struct siginfo *, pid_t);
2490 extern __must_check bool do_notify_parent(struct task_struct *, int);
2491 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
2492 extern void force_sig(int, struct task_struct *);
2493 extern int send_sig(int, struct task_struct *, int);
2494 extern int zap_other_threads(struct task_struct *p);
2495 extern struct sigqueue *sigqueue_alloc(void);
2496 extern void sigqueue_free(struct sigqueue *);
2497 extern int send_sigqueue(struct sigqueue *, struct task_struct *, int group);
2498 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
2499
2500 static inline void restore_saved_sigmask(void)
2501 {
2502 if (test_and_clear_restore_sigmask())
2503 __set_current_blocked(&current->saved_sigmask);
2504 }
2505
2506 static inline sigset_t *sigmask_to_save(void)
2507 {
2508 sigset_t *res = &current->blocked;
2509 if (unlikely(test_restore_sigmask()))
2510 res = &current->saved_sigmask;
2511 return res;
2512 }
2513
2514 static inline int kill_cad_pid(int sig, int priv)
2515 {
2516 return kill_pid(cad_pid, sig, priv);
2517 }
2518
2519 /* These can be the second arg to send_sig_info/send_group_sig_info. */
2520 #define SEND_SIG_NOINFO ((struct siginfo *) 0)
2521 #define SEND_SIG_PRIV ((struct siginfo *) 1)
2522 #define SEND_SIG_FORCED ((struct siginfo *) 2)
2523
2524 /*
2525 * True if we are on the alternate signal stack.
2526 */
2527 static inline int on_sig_stack(unsigned long sp)
2528 {
2529 #ifdef CONFIG_STACK_GROWSUP
2530 return sp >= current->sas_ss_sp &&
2531 sp - current->sas_ss_sp < current->sas_ss_size;
2532 #else
2533 return sp > current->sas_ss_sp &&
2534 sp - current->sas_ss_sp <= current->sas_ss_size;
2535 #endif
2536 }
2537
2538 static inline int sas_ss_flags(unsigned long sp)
2539 {
2540 if (!current->sas_ss_size)
2541 return SS_DISABLE;
2542
2543 return on_sig_stack(sp) ? SS_ONSTACK : 0;
2544 }
2545
2546 static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig)
2547 {
2548 if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp))
2549 #ifdef CONFIG_STACK_GROWSUP
2550 return current->sas_ss_sp;
2551 #else
2552 return current->sas_ss_sp + current->sas_ss_size;
2553 #endif
2554 return sp;
2555 }
2556
2557 /*
2558 * Routines for handling mm_structs
2559 */
2560 extern struct mm_struct * mm_alloc(void);
2561
2562 /* mmdrop drops the mm and the page tables */
2563 extern void __mmdrop(struct mm_struct *);
2564 static inline void mmdrop(struct mm_struct * mm)
2565 {
2566 if (unlikely(atomic_dec_and_test(&mm->mm_count)))
2567 __mmdrop(mm);
2568 }
2569
2570 /* mmput gets rid of the mappings and all user-space */
2571 extern void mmput(struct mm_struct *);
2572 /* Grab a reference to a task's mm, if it is not already going away */
2573 extern struct mm_struct *get_task_mm(struct task_struct *task);
2574 /*
2575 * Grab a reference to a task's mm, if it is not already going away
2576 * and ptrace_may_access with the mode parameter passed to it
2577 * succeeds.
2578 */
2579 extern struct mm_struct *mm_access(struct task_struct *task, unsigned int mode);
2580 /* Remove the current tasks stale references to the old mm_struct */
2581 extern void mm_release(struct task_struct *, struct mm_struct *);
2582
2583 #ifdef CONFIG_HAVE_COPY_THREAD_TLS
2584 extern int copy_thread_tls(unsigned long, unsigned long, unsigned long,
2585 struct task_struct *, unsigned long);
2586 #else
2587 extern int copy_thread(unsigned long, unsigned long, unsigned long,
2588 struct task_struct *);
2589
2590 /* Architectures that haven't opted into copy_thread_tls get the tls argument
2591 * via pt_regs, so ignore the tls argument passed via C. */
2592 static inline int copy_thread_tls(
2593 unsigned long clone_flags, unsigned long sp, unsigned long arg,
2594 struct task_struct *p, unsigned long tls)
2595 {
2596 return copy_thread(clone_flags, sp, arg, p);
2597 }
2598 #endif
2599 extern void flush_thread(void);
2600 extern void exit_thread(void);
2601
2602 extern void exit_files(struct task_struct *);
2603 extern void __cleanup_sighand(struct sighand_struct *);
2604
2605 extern void exit_itimers(struct signal_struct *);
2606 extern void flush_itimer_signals(void);
2607
2608 extern void do_group_exit(int);
2609
2610 extern int do_execve(struct filename *,
2611 const char __user * const __user *,
2612 const char __user * const __user *);
2613 extern int do_execveat(int, struct filename *,
2614 const char __user * const __user *,
2615 const char __user * const __user *,
2616 int);
2617 extern long _do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *, unsigned long);
2618 extern long do_fork(unsigned long, unsigned long, unsigned long, int __user *, int __user *);
2619 struct task_struct *fork_idle(int);
2620 extern pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
2621
2622 extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec);
2623 static inline void set_task_comm(struct task_struct *tsk, const char *from)
2624 {
2625 __set_task_comm(tsk, from, false);
2626 }
2627 extern char *get_task_comm(char *to, struct task_struct *tsk);
2628
2629 #ifdef CONFIG_SMP
2630 void scheduler_ipi(void);
2631 extern unsigned long wait_task_inactive(struct task_struct *, long match_state);
2632 #else
2633 static inline void scheduler_ipi(void) { }
2634 static inline unsigned long wait_task_inactive(struct task_struct *p,
2635 long match_state)
2636 {
2637 return 1;
2638 }
2639 #endif
2640
2641 #define tasklist_empty() \
2642 list_empty(&init_task.tasks)
2643
2644 #define next_task(p) \
2645 list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
2646
2647 #define for_each_process(p) \
2648 for (p = &init_task ; (p = next_task(p)) != &init_task ; )
2649
2650 extern bool current_is_single_threaded(void);
2651
2652 /*
2653 * Careful: do_each_thread/while_each_thread is a double loop so
2654 * 'break' will not work as expected - use goto instead.
2655 */
2656 #define do_each_thread(g, t) \
2657 for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
2658
2659 #define while_each_thread(g, t) \
2660 while ((t = next_thread(t)) != g)
2661
2662 #define __for_each_thread(signal, t) \
2663 list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node)
2664
2665 #define for_each_thread(p, t) \
2666 __for_each_thread((p)->signal, t)
2667
2668 /* Careful: this is a double loop, 'break' won't work as expected. */
2669 #define for_each_process_thread(p, t) \
2670 for_each_process(p) for_each_thread(p, t)
2671
2672 static inline int get_nr_threads(struct task_struct *tsk)
2673 {
2674 return tsk->signal->nr_threads;
2675 }
2676
2677 static inline bool thread_group_leader(struct task_struct *p)
2678 {
2679 return p->exit_signal >= 0;
2680 }
2681
2682 /* Do to the insanities of de_thread it is possible for a process
2683 * to have the pid of the thread group leader without actually being
2684 * the thread group leader. For iteration through the pids in proc
2685 * all we care about is that we have a task with the appropriate
2686 * pid, we don't actually care if we have the right task.
2687 */
2688 static inline bool has_group_leader_pid(struct task_struct *p)
2689 {
2690 return task_pid(p) == p->signal->leader_pid;
2691 }
2692
2693 static inline
2694 bool same_thread_group(struct task_struct *p1, struct task_struct *p2)
2695 {
2696 return p1->signal == p2->signal;
2697 }
2698
2699 static inline struct task_struct *next_thread(const struct task_struct *p)
2700 {
2701 return list_entry_rcu(p->thread_group.next,
2702 struct task_struct, thread_group);
2703 }
2704
2705 static inline int thread_group_empty(struct task_struct *p)
2706 {
2707 return list_empty(&p->thread_group);
2708 }
2709
2710 #define delay_group_leader(p) \
2711 (thread_group_leader(p) && !thread_group_empty(p))
2712
2713 /*
2714 * Protects ->fs, ->files, ->mm, ->group_info, ->comm, keyring
2715 * subscriptions and synchronises with wait4(). Also used in procfs. Also
2716 * pins the final release of task.io_context. Also protects ->cpuset and
2717 * ->cgroup.subsys[]. And ->vfork_done.
2718 *
2719 * Nests both inside and outside of read_lock(&tasklist_lock).
2720 * It must not be nested with write_lock_irq(&tasklist_lock),
2721 * neither inside nor outside.
2722 */
2723 static inline void task_lock(struct task_struct *p)
2724 {
2725 spin_lock(&p->alloc_lock);
2726 }
2727
2728 static inline void task_unlock(struct task_struct *p)
2729 {
2730 spin_unlock(&p->alloc_lock);
2731 }
2732
2733 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
2734 unsigned long *flags);
2735
2736 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
2737 unsigned long *flags)
2738 {
2739 struct sighand_struct *ret;
2740
2741 ret = __lock_task_sighand(tsk, flags);
2742 (void)__cond_lock(&tsk->sighand->siglock, ret);
2743 return ret;
2744 }
2745
2746 static inline void unlock_task_sighand(struct task_struct *tsk,
2747 unsigned long *flags)
2748 {
2749 spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
2750 }
2751
2752 /**
2753 * threadgroup_change_begin - mark the beginning of changes to a threadgroup
2754 * @tsk: task causing the changes
2755 *
2756 * All operations which modify a threadgroup - a new thread joining the
2757 * group, death of a member thread (the assertion of PF_EXITING) and
2758 * exec(2) dethreading the process and replacing the leader - are wrapped
2759 * by threadgroup_change_{begin|end}(). This is to provide a place which
2760 * subsystems needing threadgroup stability can hook into for
2761 * synchronization.
2762 */
2763 static inline void threadgroup_change_begin(struct task_struct *tsk)
2764 {
2765 might_sleep();
2766 cgroup_threadgroup_change_begin(tsk);
2767 }
2768
2769 /**
2770 * threadgroup_change_end - mark the end of changes to a threadgroup
2771 * @tsk: task causing the changes
2772 *
2773 * See threadgroup_change_begin().
2774 */
2775 static inline void threadgroup_change_end(struct task_struct *tsk)
2776 {
2777 cgroup_threadgroup_change_end(tsk);
2778 }
2779
2780 #ifndef __HAVE_THREAD_FUNCTIONS
2781
2782 #define task_thread_info(task) ((struct thread_info *)(task)->stack)
2783 #define task_stack_page(task) ((task)->stack)
2784
2785 static inline void setup_thread_stack(struct task_struct *p, struct task_struct *org)
2786 {
2787 *task_thread_info(p) = *task_thread_info(org);
2788 task_thread_info(p)->task = p;
2789 }
2790
2791 /*
2792 * Return the address of the last usable long on the stack.
2793 *
2794 * When the stack grows down, this is just above the thread
2795 * info struct. Going any lower will corrupt the threadinfo.
2796 *
2797 * When the stack grows up, this is the highest address.
2798 * Beyond that position, we corrupt data on the next page.
2799 */
2800 static inline unsigned long *end_of_stack(struct task_struct *p)
2801 {
2802 #ifdef CONFIG_STACK_GROWSUP
2803 return (unsigned long *)((unsigned long)task_thread_info(p) + THREAD_SIZE) - 1;
2804 #else
2805 return (unsigned long *)(task_thread_info(p) + 1);
2806 #endif
2807 }
2808
2809 #endif
2810 #define task_stack_end_corrupted(task) \
2811 (*(end_of_stack(task)) != STACK_END_MAGIC)
2812
2813 static inline int object_is_on_stack(void *obj)
2814 {
2815 void *stack = task_stack_page(current);
2816
2817 return (obj >= stack) && (obj < (stack + THREAD_SIZE));
2818 }
2819
2820 extern void thread_info_cache_init(void);
2821
2822 #ifdef CONFIG_DEBUG_STACK_USAGE
2823 static inline unsigned long stack_not_used(struct task_struct *p)
2824 {
2825 unsigned long *n = end_of_stack(p);
2826
2827 do { /* Skip over canary */
2828 n++;
2829 } while (!*n);
2830
2831 return (unsigned long)n - (unsigned long)end_of_stack(p);
2832 }
2833 #endif
2834 extern void set_task_stack_end_magic(struct task_struct *tsk);
2835
2836 /* set thread flags in other task's structures
2837 * - see asm/thread_info.h for TIF_xxxx flags available
2838 */
2839 static inline void set_tsk_thread_flag(struct task_struct *tsk, int flag)
2840 {
2841 set_ti_thread_flag(task_thread_info(tsk), flag);
2842 }
2843
2844 static inline void clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2845 {
2846 clear_ti_thread_flag(task_thread_info(tsk), flag);
2847 }
2848
2849 static inline int test_and_set_tsk_thread_flag(struct task_struct *tsk, int flag)
2850 {
2851 return test_and_set_ti_thread_flag(task_thread_info(tsk), flag);
2852 }
2853
2854 static inline int test_and_clear_tsk_thread_flag(struct task_struct *tsk, int flag)
2855 {
2856 return test_and_clear_ti_thread_flag(task_thread_info(tsk), flag);
2857 }
2858
2859 static inline int test_tsk_thread_flag(struct task_struct *tsk, int flag)
2860 {
2861 return test_ti_thread_flag(task_thread_info(tsk), flag);
2862 }
2863
2864 static inline void set_tsk_need_resched(struct task_struct *tsk)
2865 {
2866 set_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2867 }
2868
2869 static inline void clear_tsk_need_resched(struct task_struct *tsk)
2870 {
2871 clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED);
2872 }
2873
2874 static inline int test_tsk_need_resched(struct task_struct *tsk)
2875 {
2876 return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED));
2877 }
2878
2879 static inline int restart_syscall(void)
2880 {
2881 set_tsk_thread_flag(current, TIF_SIGPENDING);
2882 return -ERESTARTNOINTR;
2883 }
2884
2885 static inline int signal_pending(struct task_struct *p)
2886 {
2887 return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
2888 }
2889
2890 static inline int __fatal_signal_pending(struct task_struct *p)
2891 {
2892 return unlikely(sigismember(&p->pending.signal, SIGKILL));
2893 }
2894
2895 static inline int fatal_signal_pending(struct task_struct *p)
2896 {
2897 return signal_pending(p) && __fatal_signal_pending(p);
2898 }
2899
2900 static inline int signal_pending_state(long state, struct task_struct *p)
2901 {
2902 if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
2903 return 0;
2904 if (!signal_pending(p))
2905 return 0;
2906
2907 return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
2908 }
2909
2910 /*
2911 * cond_resched() and cond_resched_lock(): latency reduction via
2912 * explicit rescheduling in places that are safe. The return
2913 * value indicates whether a reschedule was done in fact.
2914 * cond_resched_lock() will drop the spinlock before scheduling,
2915 * cond_resched_softirq() will enable bhs before scheduling.
2916 */
2917 extern int _cond_resched(void);
2918
2919 #define cond_resched() ({ \
2920 ___might_sleep(__FILE__, __LINE__, 0); \
2921 _cond_resched(); \
2922 })
2923
2924 extern int __cond_resched_lock(spinlock_t *lock);
2925
2926 #define cond_resched_lock(lock) ({ \
2927 ___might_sleep(__FILE__, __LINE__, PREEMPT_LOCK_OFFSET);\
2928 __cond_resched_lock(lock); \
2929 })
2930
2931 extern int __cond_resched_softirq(void);
2932
2933 #define cond_resched_softirq() ({ \
2934 ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \
2935 __cond_resched_softirq(); \
2936 })
2937
2938 static inline void cond_resched_rcu(void)
2939 {
2940 #if defined(CONFIG_DEBUG_ATOMIC_SLEEP) || !defined(CONFIG_PREEMPT_RCU)
2941 rcu_read_unlock();
2942 cond_resched();
2943 rcu_read_lock();
2944 #endif
2945 }
2946
2947 /*
2948 * Does a critical section need to be broken due to another
2949 * task waiting?: (technically does not depend on CONFIG_PREEMPT,
2950 * but a general need for low latency)
2951 */
2952 static inline int spin_needbreak(spinlock_t *lock)
2953 {
2954 #ifdef CONFIG_PREEMPT
2955 return spin_is_contended(lock);
2956 #else
2957 return 0;
2958 #endif
2959 }
2960
2961 /*
2962 * Idle thread specific functions to determine the need_resched
2963 * polling state.
2964 */
2965 #ifdef TIF_POLLING_NRFLAG
2966 static inline int tsk_is_polling(struct task_struct *p)
2967 {
2968 return test_tsk_thread_flag(p, TIF_POLLING_NRFLAG);
2969 }
2970
2971 static inline void __current_set_polling(void)
2972 {
2973 set_thread_flag(TIF_POLLING_NRFLAG);
2974 }
2975
2976 static inline bool __must_check current_set_polling_and_test(void)
2977 {
2978 __current_set_polling();
2979
2980 /*
2981 * Polling state must be visible before we test NEED_RESCHED,
2982 * paired by resched_curr()
2983 */
2984 smp_mb__after_atomic();
2985
2986 return unlikely(tif_need_resched());
2987 }
2988
2989 static inline void __current_clr_polling(void)
2990 {
2991 clear_thread_flag(TIF_POLLING_NRFLAG);
2992 }
2993
2994 static inline bool __must_check current_clr_polling_and_test(void)
2995 {
2996 __current_clr_polling();
2997
2998 /*
2999 * Polling state must be visible before we test NEED_RESCHED,
3000 * paired by resched_curr()
3001 */
3002 smp_mb__after_atomic();
3003
3004 return unlikely(tif_need_resched());
3005 }
3006
3007 #else
3008 static inline int tsk_is_polling(struct task_struct *p) { return 0; }
3009 static inline void __current_set_polling(void) { }
3010 static inline void __current_clr_polling(void) { }
3011
3012 static inline bool __must_check current_set_polling_and_test(void)
3013 {
3014 return unlikely(tif_need_resched());
3015 }
3016 static inline bool __must_check current_clr_polling_and_test(void)
3017 {
3018 return unlikely(tif_need_resched());
3019 }
3020 #endif
3021
3022 static inline void current_clr_polling(void)
3023 {
3024 __current_clr_polling();
3025
3026 /*
3027 * Ensure we check TIF_NEED_RESCHED after we clear the polling bit.
3028 * Once the bit is cleared, we'll get IPIs with every new
3029 * TIF_NEED_RESCHED and the IPI handler, scheduler_ipi(), will also
3030 * fold.
3031 */
3032 smp_mb(); /* paired with resched_curr() */
3033
3034 preempt_fold_need_resched();
3035 }
3036
3037 static __always_inline bool need_resched(void)
3038 {
3039 return unlikely(tif_need_resched());
3040 }
3041
3042 /*
3043 * Thread group CPU time accounting.
3044 */
3045 void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times);
3046 void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times);
3047
3048 /*
3049 * Reevaluate whether the task has signals pending delivery.
3050 * Wake the task if so.
3051 * This is required every time the blocked sigset_t changes.
3052 * callers must hold sighand->siglock.
3053 */
3054 extern void recalc_sigpending_and_wake(struct task_struct *t);
3055 extern void recalc_sigpending(void);
3056
3057 extern void signal_wake_up_state(struct task_struct *t, unsigned int state);
3058
3059 static inline void signal_wake_up(struct task_struct *t, bool resume)
3060 {
3061 signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
3062 }
3063 static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
3064 {
3065 signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
3066 }
3067
3068 /*
3069 * Wrappers for p->thread_info->cpu access. No-op on UP.
3070 */
3071 #ifdef CONFIG_SMP
3072
3073 static inline unsigned int task_cpu(const struct task_struct *p)
3074 {
3075 return task_thread_info(p)->cpu;
3076 }
3077
3078 static inline int task_node(const struct task_struct *p)
3079 {
3080 return cpu_to_node(task_cpu(p));
3081 }
3082
3083 extern void set_task_cpu(struct task_struct *p, unsigned int cpu);
3084
3085 #else
3086
3087 static inline unsigned int task_cpu(const struct task_struct *p)
3088 {
3089 return 0;
3090 }
3091
3092 static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
3093 {
3094 }
3095
3096 #endif /* CONFIG_SMP */
3097
3098 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
3099 extern long sched_getaffinity(pid_t pid, struct cpumask *mask);
3100
3101 #ifdef CONFIG_CGROUP_SCHED
3102 extern struct task_group root_task_group;
3103 #endif /* CONFIG_CGROUP_SCHED */
3104
3105 extern int task_can_switch_user(struct user_struct *up,
3106 struct task_struct *tsk);
3107
3108 #ifdef CONFIG_TASK_XACCT
3109 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3110 {
3111 tsk->ioac.rchar += amt;
3112 }
3113
3114 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3115 {
3116 tsk->ioac.wchar += amt;
3117 }
3118
3119 static inline void inc_syscr(struct task_struct *tsk)
3120 {
3121 tsk->ioac.syscr++;
3122 }
3123
3124 static inline void inc_syscw(struct task_struct *tsk)
3125 {
3126 tsk->ioac.syscw++;
3127 }
3128 #else
3129 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
3130 {
3131 }
3132
3133 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
3134 {
3135 }
3136
3137 static inline void inc_syscr(struct task_struct *tsk)
3138 {
3139 }
3140
3141 static inline void inc_syscw(struct task_struct *tsk)
3142 {
3143 }
3144 #endif
3145
3146 #ifndef TASK_SIZE_OF
3147 #define TASK_SIZE_OF(tsk) TASK_SIZE
3148 #endif
3149
3150 #ifdef CONFIG_MEMCG
3151 extern void mm_update_next_owner(struct mm_struct *mm);
3152 #else
3153 static inline void mm_update_next_owner(struct mm_struct *mm)
3154 {
3155 }
3156 #endif /* CONFIG_MEMCG */
3157
3158 static inline unsigned long task_rlimit(const struct task_struct *tsk,
3159 unsigned int limit)
3160 {
3161 return READ_ONCE(tsk->signal->rlim[limit].rlim_cur);
3162 }
3163
3164 static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
3165 unsigned int limit)
3166 {
3167 return READ_ONCE(tsk->signal->rlim[limit].rlim_max);
3168 }
3169
3170 static inline unsigned long rlimit(unsigned int limit)
3171 {
3172 return task_rlimit(current, limit);
3173 }
3174
3175 static inline unsigned long rlimit_max(unsigned int limit)
3176 {
3177 return task_rlimit_max(current, limit);
3178 }
3179
3180 #endif
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