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b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
3f07c014 IM |
2 | #ifndef _LINUX_SCHED_SIGNAL_H |
3 | #define _LINUX_SCHED_SIGNAL_H | |
4 | ||
b2d09103 | 5 | #include <linux/rculist.h> |
f361bf4a | 6 | #include <linux/signal.h> |
3f07c014 | 7 | #include <linux/sched.h> |
1e4bae64 | 8 | #include <linux/sched/jobctl.h> |
9164bb4a | 9 | #include <linux/sched/task.h> |
2a1f062a | 10 | #include <linux/cred.h> |
3f07c014 | 11 | |
c3edc401 IM |
12 | /* |
13 | * Types defining task->signal and task->sighand and APIs using them: | |
14 | */ | |
15 | ||
16 | struct sighand_struct { | |
17 | atomic_t count; | |
18 | struct k_sigaction action[_NSIG]; | |
19 | spinlock_t siglock; | |
20 | wait_queue_head_t signalfd_wqh; | |
21 | }; | |
22 | ||
8d88460e IM |
23 | /* |
24 | * Per-process accounting stats: | |
25 | */ | |
26 | struct pacct_struct { | |
27 | int ac_flag; | |
28 | long ac_exitcode; | |
29 | unsigned long ac_mem; | |
30 | u64 ac_utime, ac_stime; | |
31 | unsigned long ac_minflt, ac_majflt; | |
32 | }; | |
33 | ||
34 | struct cpu_itimer { | |
35 | u64 expires; | |
36 | u64 incr; | |
37 | }; | |
38 | ||
1050b27c IM |
39 | /* |
40 | * This is the atomic variant of task_cputime, which can be used for | |
41 | * storing and updating task_cputime statistics without locking. | |
42 | */ | |
43 | struct task_cputime_atomic { | |
44 | atomic64_t utime; | |
45 | atomic64_t stime; | |
46 | atomic64_t sum_exec_runtime; | |
47 | }; | |
48 | ||
49 | #define INIT_CPUTIME_ATOMIC \ | |
50 | (struct task_cputime_atomic) { \ | |
51 | .utime = ATOMIC64_INIT(0), \ | |
52 | .stime = ATOMIC64_INIT(0), \ | |
53 | .sum_exec_runtime = ATOMIC64_INIT(0), \ | |
54 | } | |
55 | /** | |
56 | * struct thread_group_cputimer - thread group interval timer counts | |
57 | * @cputime_atomic: atomic thread group interval timers. | |
58 | * @running: true when there are timers running and | |
59 | * @cputime_atomic receives updates. | |
60 | * @checking_timer: true when a thread in the group is in the | |
61 | * process of checking for thread group timers. | |
62 | * | |
63 | * This structure contains the version of task_cputime, above, that is | |
64 | * used for thread group CPU timer calculations. | |
65 | */ | |
66 | struct thread_group_cputimer { | |
67 | struct task_cputime_atomic cputime_atomic; | |
68 | bool running; | |
69 | bool checking_timer; | |
70 | }; | |
71 | ||
c3edc401 IM |
72 | /* |
73 | * NOTE! "signal_struct" does not have its own | |
74 | * locking, because a shared signal_struct always | |
75 | * implies a shared sighand_struct, so locking | |
76 | * sighand_struct is always a proper superset of | |
77 | * the locking of signal_struct. | |
78 | */ | |
79 | struct signal_struct { | |
80 | atomic_t sigcnt; | |
81 | atomic_t live; | |
82 | int nr_threads; | |
83 | struct list_head thread_head; | |
84 | ||
85 | wait_queue_head_t wait_chldexit; /* for wait4() */ | |
86 | ||
87 | /* current thread group signal load-balancing target: */ | |
88 | struct task_struct *curr_target; | |
89 | ||
90 | /* shared signal handling: */ | |
91 | struct sigpending shared_pending; | |
92 | ||
93 | /* thread group exit support */ | |
94 | int group_exit_code; | |
95 | /* overloaded: | |
96 | * - notify group_exit_task when ->count is equal to notify_count | |
97 | * - everyone except group_exit_task is stopped during signal delivery | |
98 | * of fatal signals, group_exit_task processes the signal. | |
99 | */ | |
100 | int notify_count; | |
101 | struct task_struct *group_exit_task; | |
102 | ||
103 | /* thread group stop support, overloads group_exit_code too */ | |
104 | int group_stop_count; | |
105 | unsigned int flags; /* see SIGNAL_* flags below */ | |
106 | ||
107 | /* | |
108 | * PR_SET_CHILD_SUBREAPER marks a process, like a service | |
109 | * manager, to re-parent orphan (double-forking) child processes | |
110 | * to this process instead of 'init'. The service manager is | |
111 | * able to receive SIGCHLD signals and is able to investigate | |
112 | * the process until it calls wait(). All children of this | |
113 | * process will inherit a flag if they should look for a | |
114 | * child_subreaper process at exit. | |
115 | */ | |
116 | unsigned int is_child_subreaper:1; | |
117 | unsigned int has_child_subreaper:1; | |
118 | ||
119 | #ifdef CONFIG_POSIX_TIMERS | |
120 | ||
121 | /* POSIX.1b Interval Timers */ | |
122 | int posix_timer_id; | |
123 | struct list_head posix_timers; | |
124 | ||
125 | /* ITIMER_REAL timer for the process */ | |
126 | struct hrtimer real_timer; | |
127 | ktime_t it_real_incr; | |
128 | ||
129 | /* | |
130 | * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use | |
131 | * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these | |
132 | * values are defined to 0 and 1 respectively | |
133 | */ | |
134 | struct cpu_itimer it[2]; | |
135 | ||
136 | /* | |
137 | * Thread group totals for process CPU timers. | |
138 | * See thread_group_cputimer(), et al, for details. | |
139 | */ | |
140 | struct thread_group_cputimer cputimer; | |
141 | ||
142 | /* Earliest-expiration cache. */ | |
143 | struct task_cputime cputime_expires; | |
144 | ||
145 | struct list_head cpu_timers[3]; | |
146 | ||
147 | #endif | |
148 | ||
2c470475 | 149 | /* PID/PID hash table linkage. */ |
2c470475 | 150 | struct pid *pids[PIDTYPE_MAX]; |
c3edc401 IM |
151 | |
152 | #ifdef CONFIG_NO_HZ_FULL | |
153 | atomic_t tick_dep_mask; | |
154 | #endif | |
155 | ||
156 | struct pid *tty_old_pgrp; | |
157 | ||
158 | /* boolean value for session group leader */ | |
159 | int leader; | |
160 | ||
161 | struct tty_struct *tty; /* NULL if no tty */ | |
162 | ||
163 | #ifdef CONFIG_SCHED_AUTOGROUP | |
164 | struct autogroup *autogroup; | |
165 | #endif | |
166 | /* | |
167 | * Cumulative resource counters for dead threads in the group, | |
168 | * and for reaped dead child processes forked by this group. | |
169 | * Live threads maintain their own counters and add to these | |
170 | * in __exit_signal, except for the group leader. | |
171 | */ | |
172 | seqlock_t stats_lock; | |
173 | u64 utime, stime, cutime, cstime; | |
174 | u64 gtime; | |
175 | u64 cgtime; | |
176 | struct prev_cputime prev_cputime; | |
177 | unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw; | |
178 | unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt; | |
179 | unsigned long inblock, oublock, cinblock, coublock; | |
180 | unsigned long maxrss, cmaxrss; | |
181 | struct task_io_accounting ioac; | |
182 | ||
183 | /* | |
184 | * Cumulative ns of schedule CPU time fo dead threads in the | |
185 | * group, not including a zombie group leader, (This only differs | |
186 | * from jiffies_to_ns(utime + stime) if sched_clock uses something | |
187 | * other than jiffies.) | |
188 | */ | |
189 | unsigned long long sum_sched_runtime; | |
190 | ||
191 | /* | |
192 | * We don't bother to synchronize most readers of this at all, | |
193 | * because there is no reader checking a limit that actually needs | |
194 | * to get both rlim_cur and rlim_max atomically, and either one | |
195 | * alone is a single word that can safely be read normally. | |
196 | * getrlimit/setrlimit use task_lock(current->group_leader) to | |
197 | * protect this instead of the siglock, because they really | |
198 | * have no need to disable irqs. | |
199 | */ | |
200 | struct rlimit rlim[RLIM_NLIMITS]; | |
201 | ||
202 | #ifdef CONFIG_BSD_PROCESS_ACCT | |
203 | struct pacct_struct pacct; /* per-process accounting information */ | |
204 | #endif | |
205 | #ifdef CONFIG_TASKSTATS | |
206 | struct taskstats *stats; | |
207 | #endif | |
208 | #ifdef CONFIG_AUDIT | |
209 | unsigned audit_tty; | |
210 | struct tty_audit_buf *tty_audit_buf; | |
211 | #endif | |
212 | ||
213 | /* | |
214 | * Thread is the potential origin of an oom condition; kill first on | |
215 | * oom | |
216 | */ | |
217 | bool oom_flag_origin; | |
218 | short oom_score_adj; /* OOM kill score adjustment */ | |
219 | short oom_score_adj_min; /* OOM kill score adjustment min value. | |
220 | * Only settable by CAP_SYS_RESOURCE. */ | |
221 | struct mm_struct *oom_mm; /* recorded mm when the thread group got | |
222 | * killed by the oom killer */ | |
223 | ||
224 | struct mutex cred_guard_mutex; /* guard against foreign influences on | |
225 | * credential calculations | |
226 | * (notably. ptrace) */ | |
3859a271 | 227 | } __randomize_layout; |
c3edc401 IM |
228 | |
229 | /* | |
230 | * Bits in flags field of signal_struct. | |
231 | */ | |
232 | #define SIGNAL_STOP_STOPPED 0x00000001 /* job control stop in effect */ | |
233 | #define SIGNAL_STOP_CONTINUED 0x00000002 /* SIGCONT since WCONTINUED reap */ | |
234 | #define SIGNAL_GROUP_EXIT 0x00000004 /* group exit in progress */ | |
235 | #define SIGNAL_GROUP_COREDUMP 0x00000008 /* coredump in progress */ | |
236 | /* | |
237 | * Pending notifications to parent. | |
238 | */ | |
239 | #define SIGNAL_CLD_STOPPED 0x00000010 | |
240 | #define SIGNAL_CLD_CONTINUED 0x00000020 | |
241 | #define SIGNAL_CLD_MASK (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED) | |
242 | ||
243 | #define SIGNAL_UNKILLABLE 0x00000040 /* for init: ignore fatal signals */ | |
244 | ||
245 | #define SIGNAL_STOP_MASK (SIGNAL_CLD_MASK | SIGNAL_STOP_STOPPED | \ | |
246 | SIGNAL_STOP_CONTINUED) | |
247 | ||
248 | static inline void signal_set_stop_flags(struct signal_struct *sig, | |
249 | unsigned int flags) | |
250 | { | |
251 | WARN_ON(sig->flags & (SIGNAL_GROUP_EXIT|SIGNAL_GROUP_COREDUMP)); | |
252 | sig->flags = (sig->flags & ~SIGNAL_STOP_MASK) | flags; | |
253 | } | |
254 | ||
255 | /* If true, all threads except ->group_exit_task have pending SIGKILL */ | |
256 | static inline int signal_group_exit(const struct signal_struct *sig) | |
257 | { | |
258 | return (sig->flags & SIGNAL_GROUP_EXIT) || | |
259 | (sig->group_exit_task != NULL); | |
260 | } | |
261 | ||
262 | extern void flush_signals(struct task_struct *); | |
263 | extern void ignore_signals(struct task_struct *); | |
264 | extern void flush_signal_handlers(struct task_struct *, int force_default); | |
265 | extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info); | |
266 | ||
267 | static inline int kernel_dequeue_signal(siginfo_t *info) | |
268 | { | |
269 | struct task_struct *tsk = current; | |
270 | siginfo_t __info; | |
271 | int ret; | |
272 | ||
273 | spin_lock_irq(&tsk->sighand->siglock); | |
274 | ret = dequeue_signal(tsk, &tsk->blocked, info ?: &__info); | |
275 | spin_unlock_irq(&tsk->sighand->siglock); | |
276 | ||
277 | return ret; | |
278 | } | |
279 | ||
280 | static inline void kernel_signal_stop(void) | |
281 | { | |
282 | spin_lock_irq(¤t->sighand->siglock); | |
283 | if (current->jobctl & JOBCTL_STOP_DEQUEUED) | |
b5bf9a90 | 284 | set_special_state(TASK_STOPPED); |
c3edc401 IM |
285 | spin_unlock_irq(¤t->sighand->siglock); |
286 | ||
287 | schedule(); | |
288 | } | |
f8ec6601 EB |
289 | #ifdef __ARCH_SI_TRAPNO |
290 | # define ___ARCH_SI_TRAPNO(_a1) , _a1 | |
291 | #else | |
292 | # define ___ARCH_SI_TRAPNO(_a1) | |
293 | #endif | |
294 | #ifdef __ia64__ | |
295 | # define ___ARCH_SI_IA64(_a1, _a2, _a3) , _a1, _a2, _a3 | |
296 | #else | |
297 | # define ___ARCH_SI_IA64(_a1, _a2, _a3) | |
298 | #endif | |
299 | ||
300 | int force_sig_fault(int sig, int code, void __user *addr | |
301 | ___ARCH_SI_TRAPNO(int trapno) | |
302 | ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr) | |
303 | , struct task_struct *t); | |
304 | int send_sig_fault(int sig, int code, void __user *addr | |
305 | ___ARCH_SI_TRAPNO(int trapno) | |
306 | ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr) | |
307 | , struct task_struct *t); | |
308 | ||
38246735 EB |
309 | int force_sig_mceerr(int code, void __user *, short, struct task_struct *); |
310 | int send_sig_mceerr(int code, void __user *, short, struct task_struct *); | |
311 | ||
312 | int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper); | |
313 | int force_sig_pkuerr(void __user *addr, u32 pkey); | |
314 | ||
f71dd7dc EB |
315 | int force_sig_ptrace_errno_trap(int errno, void __user *addr); |
316 | ||
c3edc401 IM |
317 | extern int send_sig_info(int, struct siginfo *, struct task_struct *); |
318 | extern int force_sigsegv(int, struct task_struct *); | |
319 | extern int force_sig_info(int, struct siginfo *, struct task_struct *); | |
320 | extern int __kill_pgrp_info(int sig, struct siginfo *info, struct pid *pgrp); | |
321 | extern int kill_pid_info(int sig, struct siginfo *info, struct pid *pid); | |
322 | extern int kill_pid_info_as_cred(int, struct siginfo *, struct pid *, | |
6b4f3d01 | 323 | const struct cred *); |
c3edc401 IM |
324 | extern int kill_pgrp(struct pid *pid, int sig, int priv); |
325 | extern int kill_pid(struct pid *pid, int sig, int priv); | |
c3edc401 IM |
326 | extern __must_check bool do_notify_parent(struct task_struct *, int); |
327 | extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent); | |
328 | extern void force_sig(int, struct task_struct *); | |
329 | extern int send_sig(int, struct task_struct *, int); | |
330 | extern int zap_other_threads(struct task_struct *p); | |
331 | extern struct sigqueue *sigqueue_alloc(void); | |
332 | extern void sigqueue_free(struct sigqueue *); | |
24122c7f | 333 | extern int send_sigqueue(struct sigqueue *, struct pid *, enum pid_type); |
c3edc401 IM |
334 | extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *); |
335 | ||
2a1f062a IM |
336 | static inline int restart_syscall(void) |
337 | { | |
338 | set_tsk_thread_flag(current, TIF_SIGPENDING); | |
339 | return -ERESTARTNOINTR; | |
340 | } | |
341 | ||
342 | static inline int signal_pending(struct task_struct *p) | |
343 | { | |
344 | return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING)); | |
345 | } | |
346 | ||
347 | static inline int __fatal_signal_pending(struct task_struct *p) | |
348 | { | |
349 | return unlikely(sigismember(&p->pending.signal, SIGKILL)); | |
350 | } | |
351 | ||
352 | static inline int fatal_signal_pending(struct task_struct *p) | |
353 | { | |
354 | return signal_pending(p) && __fatal_signal_pending(p); | |
355 | } | |
356 | ||
357 | static inline int signal_pending_state(long state, struct task_struct *p) | |
358 | { | |
359 | if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL))) | |
360 | return 0; | |
361 | if (!signal_pending(p)) | |
362 | return 0; | |
363 | ||
364 | return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p); | |
365 | } | |
366 | ||
367 | /* | |
368 | * Reevaluate whether the task has signals pending delivery. | |
369 | * Wake the task if so. | |
370 | * This is required every time the blocked sigset_t changes. | |
371 | * callers must hold sighand->siglock. | |
372 | */ | |
373 | extern void recalc_sigpending_and_wake(struct task_struct *t); | |
374 | extern void recalc_sigpending(void); | |
088fe47c | 375 | extern void calculate_sigpending(void); |
2a1f062a IM |
376 | |
377 | extern void signal_wake_up_state(struct task_struct *t, unsigned int state); | |
378 | ||
379 | static inline void signal_wake_up(struct task_struct *t, bool resume) | |
380 | { | |
381 | signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0); | |
382 | } | |
383 | static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume) | |
384 | { | |
385 | signal_wake_up_state(t, resume ? __TASK_TRACED : 0); | |
386 | } | |
387 | ||
924de3b8 EB |
388 | void task_join_group_stop(struct task_struct *task); |
389 | ||
c3edc401 IM |
390 | #ifdef TIF_RESTORE_SIGMASK |
391 | /* | |
392 | * Legacy restore_sigmask accessors. These are inefficient on | |
393 | * SMP architectures because they require atomic operations. | |
394 | */ | |
395 | ||
396 | /** | |
397 | * set_restore_sigmask() - make sure saved_sigmask processing gets done | |
398 | * | |
399 | * This sets TIF_RESTORE_SIGMASK and ensures that the arch signal code | |
400 | * will run before returning to user mode, to process the flag. For | |
401 | * all callers, TIF_SIGPENDING is already set or it's no harm to set | |
402 | * it. TIF_RESTORE_SIGMASK need not be in the set of bits that the | |
403 | * arch code will notice on return to user mode, in case those bits | |
404 | * are scarce. We set TIF_SIGPENDING here to ensure that the arch | |
405 | * signal code always gets run when TIF_RESTORE_SIGMASK is set. | |
406 | */ | |
407 | static inline void set_restore_sigmask(void) | |
408 | { | |
409 | set_thread_flag(TIF_RESTORE_SIGMASK); | |
410 | WARN_ON(!test_thread_flag(TIF_SIGPENDING)); | |
411 | } | |
412 | static inline void clear_restore_sigmask(void) | |
413 | { | |
414 | clear_thread_flag(TIF_RESTORE_SIGMASK); | |
415 | } | |
416 | static inline bool test_restore_sigmask(void) | |
417 | { | |
418 | return test_thread_flag(TIF_RESTORE_SIGMASK); | |
419 | } | |
420 | static inline bool test_and_clear_restore_sigmask(void) | |
421 | { | |
422 | return test_and_clear_thread_flag(TIF_RESTORE_SIGMASK); | |
423 | } | |
424 | ||
425 | #else /* TIF_RESTORE_SIGMASK */ | |
426 | ||
427 | /* Higher-quality implementation, used if TIF_RESTORE_SIGMASK doesn't exist. */ | |
428 | static inline void set_restore_sigmask(void) | |
429 | { | |
430 | current->restore_sigmask = true; | |
431 | WARN_ON(!test_thread_flag(TIF_SIGPENDING)); | |
432 | } | |
433 | static inline void clear_restore_sigmask(void) | |
434 | { | |
435 | current->restore_sigmask = false; | |
436 | } | |
437 | static inline bool test_restore_sigmask(void) | |
438 | { | |
439 | return current->restore_sigmask; | |
440 | } | |
441 | static inline bool test_and_clear_restore_sigmask(void) | |
442 | { | |
443 | if (!current->restore_sigmask) | |
444 | return false; | |
445 | current->restore_sigmask = false; | |
446 | return true; | |
447 | } | |
448 | #endif | |
449 | ||
450 | static inline void restore_saved_sigmask(void) | |
451 | { | |
452 | if (test_and_clear_restore_sigmask()) | |
453 | __set_current_blocked(¤t->saved_sigmask); | |
454 | } | |
455 | ||
456 | static inline sigset_t *sigmask_to_save(void) | |
457 | { | |
458 | sigset_t *res = ¤t->blocked; | |
459 | if (unlikely(test_restore_sigmask())) | |
460 | res = ¤t->saved_sigmask; | |
461 | return res; | |
462 | } | |
463 | ||
464 | static inline int kill_cad_pid(int sig, int priv) | |
465 | { | |
466 | return kill_pid(cad_pid, sig, priv); | |
467 | } | |
468 | ||
469 | /* These can be the second arg to send_sig_info/send_group_sig_info. */ | |
470 | #define SEND_SIG_NOINFO ((struct siginfo *) 0) | |
471 | #define SEND_SIG_PRIV ((struct siginfo *) 1) | |
472 | #define SEND_SIG_FORCED ((struct siginfo *) 2) | |
473 | ||
474 | /* | |
475 | * True if we are on the alternate signal stack. | |
476 | */ | |
477 | static inline int on_sig_stack(unsigned long sp) | |
478 | { | |
479 | /* | |
480 | * If the signal stack is SS_AUTODISARM then, by construction, we | |
481 | * can't be on the signal stack unless user code deliberately set | |
482 | * SS_AUTODISARM when we were already on it. | |
483 | * | |
484 | * This improves reliability: if user state gets corrupted such that | |
485 | * the stack pointer points very close to the end of the signal stack, | |
486 | * then this check will enable the signal to be handled anyway. | |
487 | */ | |
488 | if (current->sas_ss_flags & SS_AUTODISARM) | |
489 | return 0; | |
490 | ||
491 | #ifdef CONFIG_STACK_GROWSUP | |
492 | return sp >= current->sas_ss_sp && | |
493 | sp - current->sas_ss_sp < current->sas_ss_size; | |
494 | #else | |
495 | return sp > current->sas_ss_sp && | |
496 | sp - current->sas_ss_sp <= current->sas_ss_size; | |
497 | #endif | |
498 | } | |
499 | ||
500 | static inline int sas_ss_flags(unsigned long sp) | |
501 | { | |
502 | if (!current->sas_ss_size) | |
503 | return SS_DISABLE; | |
504 | ||
505 | return on_sig_stack(sp) ? SS_ONSTACK : 0; | |
506 | } | |
507 | ||
508 | static inline void sas_ss_reset(struct task_struct *p) | |
509 | { | |
510 | p->sas_ss_sp = 0; | |
511 | p->sas_ss_size = 0; | |
512 | p->sas_ss_flags = SS_DISABLE; | |
513 | } | |
514 | ||
515 | static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig) | |
516 | { | |
517 | if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp)) | |
518 | #ifdef CONFIG_STACK_GROWSUP | |
519 | return current->sas_ss_sp; | |
520 | #else | |
521 | return current->sas_ss_sp + current->sas_ss_size; | |
522 | #endif | |
523 | return sp; | |
524 | } | |
525 | ||
526 | extern void __cleanup_sighand(struct sighand_struct *); | |
527 | extern void flush_itimer_signals(void); | |
528 | ||
529 | #define tasklist_empty() \ | |
530 | list_empty(&init_task.tasks) | |
531 | ||
532 | #define next_task(p) \ | |
533 | list_entry_rcu((p)->tasks.next, struct task_struct, tasks) | |
534 | ||
535 | #define for_each_process(p) \ | |
536 | for (p = &init_task ; (p = next_task(p)) != &init_task ; ) | |
537 | ||
538 | extern bool current_is_single_threaded(void); | |
539 | ||
540 | /* | |
541 | * Careful: do_each_thread/while_each_thread is a double loop so | |
542 | * 'break' will not work as expected - use goto instead. | |
543 | */ | |
544 | #define do_each_thread(g, t) \ | |
545 | for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do | |
546 | ||
547 | #define while_each_thread(g, t) \ | |
548 | while ((t = next_thread(t)) != g) | |
549 | ||
550 | #define __for_each_thread(signal, t) \ | |
551 | list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node) | |
552 | ||
553 | #define for_each_thread(p, t) \ | |
554 | __for_each_thread((p)->signal, t) | |
555 | ||
556 | /* Careful: this is a double loop, 'break' won't work as expected. */ | |
557 | #define for_each_process_thread(p, t) \ | |
558 | for_each_process(p) for_each_thread(p, t) | |
559 | ||
560 | typedef int (*proc_visitor)(struct task_struct *p, void *data); | |
561 | void walk_process_tree(struct task_struct *top, proc_visitor, void *); | |
562 | ||
1fb53567 EB |
563 | static inline |
564 | struct pid *task_pid_type(struct task_struct *task, enum pid_type type) | |
565 | { | |
2c470475 EB |
566 | struct pid *pid; |
567 | if (type == PIDTYPE_PID) | |
568 | pid = task_pid(task); | |
569 | else | |
570 | pid = task->signal->pids[type]; | |
571 | return pid; | |
1fb53567 EB |
572 | } |
573 | ||
7a36094d EB |
574 | static inline struct pid *task_tgid(struct task_struct *task) |
575 | { | |
6883f81a | 576 | return task->signal->pids[PIDTYPE_TGID]; |
7a36094d EB |
577 | } |
578 | ||
2c470475 EB |
579 | /* |
580 | * Without tasklist or RCU lock it is not safe to dereference | |
581 | * the result of task_pgrp/task_session even if task == current, | |
582 | * we can race with another thread doing sys_setsid/sys_setpgid. | |
583 | */ | |
584 | static inline struct pid *task_pgrp(struct task_struct *task) | |
585 | { | |
586 | return task->signal->pids[PIDTYPE_PGID]; | |
587 | } | |
588 | ||
589 | static inline struct pid *task_session(struct task_struct *task) | |
590 | { | |
591 | return task->signal->pids[PIDTYPE_SID]; | |
592 | } | |
593 | ||
c3edc401 IM |
594 | static inline int get_nr_threads(struct task_struct *tsk) |
595 | { | |
596 | return tsk->signal->nr_threads; | |
597 | } | |
598 | ||
599 | static inline bool thread_group_leader(struct task_struct *p) | |
600 | { | |
601 | return p->exit_signal >= 0; | |
602 | } | |
603 | ||
604 | /* Do to the insanities of de_thread it is possible for a process | |
605 | * to have the pid of the thread group leader without actually being | |
606 | * the thread group leader. For iteration through the pids in proc | |
607 | * all we care about is that we have a task with the appropriate | |
608 | * pid, we don't actually care if we have the right task. | |
609 | */ | |
610 | static inline bool has_group_leader_pid(struct task_struct *p) | |
611 | { | |
6883f81a | 612 | return task_pid(p) == task_tgid(p); |
c3edc401 IM |
613 | } |
614 | ||
615 | static inline | |
616 | bool same_thread_group(struct task_struct *p1, struct task_struct *p2) | |
617 | { | |
618 | return p1->signal == p2->signal; | |
619 | } | |
620 | ||
621 | static inline struct task_struct *next_thread(const struct task_struct *p) | |
622 | { | |
623 | return list_entry_rcu(p->thread_group.next, | |
624 | struct task_struct, thread_group); | |
625 | } | |
626 | ||
627 | static inline int thread_group_empty(struct task_struct *p) | |
628 | { | |
629 | return list_empty(&p->thread_group); | |
630 | } | |
631 | ||
632 | #define delay_group_leader(p) \ | |
633 | (thread_group_leader(p) && !thread_group_empty(p)) | |
634 | ||
635 | extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk, | |
636 | unsigned long *flags); | |
637 | ||
638 | static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk, | |
639 | unsigned long *flags) | |
640 | { | |
641 | struct sighand_struct *ret; | |
642 | ||
643 | ret = __lock_task_sighand(tsk, flags); | |
644 | (void)__cond_lock(&tsk->sighand->siglock, ret); | |
645 | return ret; | |
646 | } | |
647 | ||
648 | static inline void unlock_task_sighand(struct task_struct *tsk, | |
649 | unsigned long *flags) | |
650 | { | |
651 | spin_unlock_irqrestore(&tsk->sighand->siglock, *flags); | |
652 | } | |
653 | ||
654 | static inline unsigned long task_rlimit(const struct task_struct *tsk, | |
655 | unsigned int limit) | |
656 | { | |
657 | return READ_ONCE(tsk->signal->rlim[limit].rlim_cur); | |
658 | } | |
659 | ||
660 | static inline unsigned long task_rlimit_max(const struct task_struct *tsk, | |
661 | unsigned int limit) | |
662 | { | |
663 | return READ_ONCE(tsk->signal->rlim[limit].rlim_max); | |
664 | } | |
665 | ||
666 | static inline unsigned long rlimit(unsigned int limit) | |
667 | { | |
668 | return task_rlimit(current, limit); | |
669 | } | |
670 | ||
671 | static inline unsigned long rlimit_max(unsigned int limit) | |
672 | { | |
673 | return task_rlimit_max(current, limit); | |
674 | } | |
675 | ||
3f07c014 | 676 | #endif /* _LINUX_SCHED_SIGNAL_H */ |