1 /*- 2 * Copyright (c) 1982, 1986, 1989, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)kern_exit.c 8.7 (Berkeley) 2/12/94 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include "opt_compat.h" 41 #include "opt_ktrace.h" 42 #include "opt_mac.h" 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/sysproto.h> 47 #include <sys/eventhandler.h> 48 #include <sys/kernel.h> 49 #include <sys/malloc.h> 50 #include <sys/lock.h> 51 #include <sys/mutex.h> 52 #include <sys/proc.h> 53 #include <sys/pioctl.h> 54 #include <sys/tty.h> 55 #include <sys/wait.h> 56 #include <sys/vmmeter.h> 57 #include <sys/vnode.h> 58 #include <sys/resourcevar.h> 59 #include <sys/signalvar.h> 60 #include <sys/sched.h> 61 #include <sys/sx.h> 62 #include <sys/syscallsubr.h> 63 #include <sys/ptrace.h> 64 #include <sys/acct.h> /* for acct_process() function prototype */ 65 #include <sys/filedesc.h> 66 #include <sys/mac.h> 67 #include <sys/shm.h> 68 #include <sys/sem.h> 69 #ifdef KTRACE 70 #include <sys/ktrace.h> 71 #endif 72 73 #include <vm/vm.h> 74 #include <vm/vm_extern.h> 75 #include <vm/vm_param.h> 76 #include <vm/pmap.h> 77 #include <vm/vm_map.h> 78 #include <vm/vm_page.h> 79 #include <vm/uma.h> 80 81 /* Required to be non-static for SysVR4 emulator */ 82 MALLOC_DEFINE(M_ZOMBIE, "zombie", "zombie proc status"); 83 84 /* 85 * exit -- 86 * Death of process. 87 * 88 * MPSAFE 89 */ 90 void 91 sys_exit(struct thread *td, struct sys_exit_args *uap) 92 { 93 94 exit1(td, W_EXITCODE(uap->rval, 0)); 95 /* NOTREACHED */ 96 } 97 98 /* 99 * Exit: deallocate address space and other resources, change proc state 100 * to zombie, and unlink proc from allproc and parent's lists. Save exit 101 * status and rusage for wait(). Check for child processes and orphan them. 102 */ 103 void 104 exit1(struct thread *td, int rv) 105 { 106 struct bintime new_switchtime; 107 struct proc *p, *nq, *q; 108 struct tty *tp; 109 struct vnode *ttyvp; 110 struct vmspace *vm; 111 struct vnode *vtmp; 112 #ifdef KTRACE 113 struct vnode *tracevp; 114 struct ucred *tracecred; 115 #endif 116 struct plimit *plim; 117 int refcnt; 118 119 /* 120 * Drop Giant if caller has it. Eventually we should warn about 121 * being called with Giant held. 122 */ 123 while (mtx_owned(&Giant)) 124 mtx_unlock(&Giant); 125 126 p = td->td_proc; 127 if (p == initproc) { 128 printf("init died (signal %d, exit %d)\n", 129 WTERMSIG(rv), WEXITSTATUS(rv)); 130 panic("Going nowhere without my init!"); 131 } 132 133 /* 134 * MUST abort all other threads before proceeding past here. 135 */ 136 PROC_LOCK(p); 137 if (p->p_flag & P_HADTHREADS) { 138 retry: 139 /* 140 * First check if some other thread got here before us.. 141 * if so, act apropriatly, (exit or suspend); 142 */ 143 thread_suspend_check(0); 144 145 /* 146 * Kill off the other threads. This requires 147 * some co-operation from other parts of the kernel 148 * so it may not be instantaneous. With this state set 149 * any thread entering the kernel from userspace will 150 * thread_exit() in trap(). Any thread attempting to 151 * sleep will return immediately with EINTR or EWOULDBLOCK 152 * which will hopefully force them to back out to userland 153 * freeing resources as they go. Any thread attempting 154 * to return to userland will thread_exit() from userret(). 155 * thread_exit() will unsuspend us when the last of the 156 * other threads exits. 157 * If there is already a thread singler after resumption, 158 * calling thread_single will fail; in that case, we just 159 * re-check all suspension request, the thread should 160 * either be suspended there or exit. 161 */ 162 if (thread_single(SINGLE_EXIT)) 163 goto retry; 164 165 /* 166 * All other activity in this process is now stopped. 167 * Threading support has been turned off. 168 */ 169 } 170 171 p->p_flag |= P_WEXIT; 172 PROC_UNLOCK(p); 173 174 /* Are we a task leader? */ 175 if (p == p->p_leader) { 176 mtx_lock(&ppeers_lock); 177 q = p->p_peers; 178 while (q != NULL) { 179 PROC_LOCK(q); 180 psignal(q, SIGKILL); 181 PROC_UNLOCK(q); 182 q = q->p_peers; 183 } 184 while (p->p_peers != NULL) 185 msleep(p, &ppeers_lock, PWAIT, "exit1", 0); 186 mtx_unlock(&ppeers_lock); 187 } 188 189 PROC_LOCK(p); 190 _STOPEVENT(p, S_EXIT, rv); 191 wakeup(&p->p_stype); /* Wakeup anyone in procfs' PIOCWAIT */ 192 PROC_UNLOCK(p); 193 194 /* 195 * Check if any loadable modules need anything done at process exit. 196 * E.g. SYSV IPC stuff 197 * XXX what if one of these generates an error? 198 */ 199 EVENTHANDLER_INVOKE(process_exit, p); 200 201 MALLOC(p->p_ru, struct rusage *, sizeof(struct rusage), 202 M_ZOMBIE, M_WAITOK); 203 /* 204 * If parent is waiting for us to exit or exec, 205 * P_PPWAIT is set; we will wakeup the parent below. 206 */ 207 PROC_LOCK(p); 208 stopprofclock(p); 209 p->p_flag &= ~(P_TRACED | P_PPWAIT); 210 SIGEMPTYSET(p->p_siglist); 211 SIGEMPTYSET(td->td_siglist); 212 213 /* 214 * Stop the real interval timer. If the handler is currently 215 * executing, prevent it from rearming itself and let it finish. 216 */ 217 if (timevalisset(&p->p_realtimer.it_value) && 218 callout_stop(&p->p_itcallout) == 0) { 219 timevalclear(&p->p_realtimer.it_interval); 220 msleep(&p->p_itcallout, &p->p_mtx, PWAIT, "ritwait", 0); 221 KASSERT(!timevalisset(&p->p_realtimer.it_value), 222 ("realtime timer is still armed")); 223 } 224 PROC_UNLOCK(p); 225 226 /* 227 * Reset any sigio structures pointing to us as a result of 228 * F_SETOWN with our pid. 229 */ 230 mtx_lock(&Giant); /* XXX: not sure if needed */ 231 funsetownlst(&p->p_sigiolst); 232 233 /* 234 * Close open files and release open-file table. 235 * This may block! 236 */ 237 fdfree(td); 238 mtx_unlock(&Giant); 239 240 /* 241 * Remove ourself from our leader's peer list and wake our leader. 242 */ 243 mtx_lock(&ppeers_lock); 244 if (p->p_leader->p_peers) { 245 q = p->p_leader; 246 while (q->p_peers != p) 247 q = q->p_peers; 248 q->p_peers = p->p_peers; 249 wakeup(p->p_leader); 250 } 251 mtx_unlock(&ppeers_lock); 252 253 /* The next two chunks should probably be moved to vmspace_exit. */ 254 vm = p->p_vmspace; 255 /* 256 * Release user portion of address space. 257 * This releases references to vnodes, 258 * which could cause I/O if the file has been unlinked. 259 * Need to do this early enough that we can still sleep. 260 * Can't free the entire vmspace as the kernel stack 261 * may be mapped within that space also. 262 * 263 * Processes sharing the same vmspace may exit in one order, and 264 * get cleaned up by vmspace_exit() in a different order. The 265 * last exiting process to reach this point releases as much of 266 * the environment as it can, and the last process cleaned up 267 * by vmspace_exit() (which decrements exitingcnt) cleans up the 268 * remainder. 269 */ 270 atomic_add_int(&vm->vm_exitingcnt, 1); 271 do 272 refcnt = vm->vm_refcnt; 273 while (!atomic_cmpset_int(&vm->vm_refcnt, refcnt, refcnt - 1)); 274 if (refcnt == 1) { 275 shmexit(vm); 276 pmap_remove_pages(vmspace_pmap(vm), vm_map_min(&vm->vm_map), 277 vm_map_max(&vm->vm_map)); 278 (void) vm_map_remove(&vm->vm_map, vm_map_min(&vm->vm_map), 279 vm_map_max(&vm->vm_map)); 280 } 281 282 mtx_lock(&Giant); 283 sx_xlock(&proctree_lock); 284 if (SESS_LEADER(p)) { 285 struct session *sp; 286 287 sp = p->p_session; 288 if (sp->s_ttyvp) { 289 /* 290 * Controlling process. 291 * Signal foreground pgrp, 292 * drain controlling terminal 293 * and revoke access to controlling terminal. 294 */ 295 if (sp->s_ttyp && (sp->s_ttyp->t_session == sp)) { 296 tp = sp->s_ttyp; 297 if (sp->s_ttyp->t_pgrp) { 298 PGRP_LOCK(sp->s_ttyp->t_pgrp); 299 pgsignal(sp->s_ttyp->t_pgrp, SIGHUP, 1); 300 PGRP_UNLOCK(sp->s_ttyp->t_pgrp); 301 } 302 /* XXX tp should be locked. */ 303 sx_xunlock(&proctree_lock); 304 (void) ttywait(tp); 305 sx_xlock(&proctree_lock); 306 /* 307 * The tty could have been revoked 308 * if we blocked. 309 */ 310 if (sp->s_ttyvp) { 311 ttyvp = sp->s_ttyvp; 312 SESS_LOCK(p->p_session); 313 sp->s_ttyvp = NULL; 314 SESS_UNLOCK(p->p_session); 315 sx_xunlock(&proctree_lock); 316 VOP_REVOKE(ttyvp, REVOKEALL); 317 vrele(ttyvp); 318 sx_xlock(&proctree_lock); 319 } 320 } 321 if (sp->s_ttyvp) { 322 ttyvp = sp->s_ttyvp; 323 SESS_LOCK(p->p_session); 324 sp->s_ttyvp = NULL; 325 SESS_UNLOCK(p->p_session); 326 vrele(ttyvp); 327 } 328 /* 329 * s_ttyp is not zero'd; we use this to indicate 330 * that the session once had a controlling terminal. 331 * (for logging and informational purposes) 332 */ 333 } 334 SESS_LOCK(p->p_session); 335 sp->s_leader = NULL; 336 SESS_UNLOCK(p->p_session); 337 } 338 fixjobc(p, p->p_pgrp, 0); 339 sx_xunlock(&proctree_lock); 340 (void)acct_process(td); 341 mtx_unlock(&Giant); 342 #ifdef KTRACE 343 /* 344 * release trace file 345 */ 346 PROC_LOCK(p); 347 mtx_lock(&ktrace_mtx); 348 p->p_traceflag = 0; /* don't trace the vrele() */ 349 tracevp = p->p_tracevp; 350 p->p_tracevp = NULL; 351 tracecred = p->p_tracecred; 352 p->p_tracecred = NULL; 353 mtx_unlock(&ktrace_mtx); 354 PROC_UNLOCK(p); 355 if (tracevp != NULL) { 356 mtx_lock(&Giant); 357 vrele(tracevp); 358 mtx_unlock(&Giant); 359 } 360 if (tracecred != NULL) 361 crfree(tracecred); 362 #endif 363 /* 364 * Release reference to text vnode 365 */ 366 if ((vtmp = p->p_textvp) != NULL) { 367 p->p_textvp = NULL; 368 mtx_lock(&Giant); 369 vrele(vtmp); 370 mtx_unlock(&Giant); 371 } 372 373 /* 374 * Release our limits structure. 375 */ 376 PROC_LOCK(p); 377 plim = p->p_limit; 378 p->p_limit = NULL; 379 PROC_UNLOCK(p); 380 lim_free(plim); 381 382 /* 383 * Remove proc from allproc queue and pidhash chain. 384 * Place onto zombproc. Unlink from parent's child list. 385 */ 386 sx_xlock(&allproc_lock); 387 LIST_REMOVE(p, p_list); 388 LIST_INSERT_HEAD(&zombproc, p, p_list); 389 LIST_REMOVE(p, p_hash); 390 sx_xunlock(&allproc_lock); 391 392 sx_xlock(&proctree_lock); 393 q = LIST_FIRST(&p->p_children); 394 if (q != NULL) /* only need this if any child is S_ZOMB */ 395 wakeup(initproc); 396 for (; q != NULL; q = nq) { 397 nq = LIST_NEXT(q, p_sibling); 398 PROC_LOCK(q); 399 proc_reparent(q, initproc); 400 q->p_sigparent = SIGCHLD; 401 /* 402 * Traced processes are killed 403 * since their existence means someone is screwing up. 404 */ 405 if (q->p_flag & P_TRACED) { 406 q->p_flag &= ~(P_TRACED | P_STOPPED_TRACE); 407 psignal(q, SIGKILL); 408 } 409 PROC_UNLOCK(q); 410 } 411 412 /* 413 * Save exit status and finalize rusage info except for times, 414 * adding in child rusage info. 415 */ 416 PROC_LOCK(p); 417 p->p_xstat = rv; 418 p->p_xthread = td; 419 p->p_stats->p_ru.ru_nvcsw++; 420 *p->p_ru = p->p_stats->p_ru; 421 ruadd(p->p_ru, &p->p_rux, &p->p_stats->p_cru, &p->p_crux); 422 423 /* 424 * Notify interested parties of our demise. 425 */ 426 KNOTE_LOCKED(&p->p_klist, NOTE_EXIT); 427 428 /* 429 * Just delete all entries in the p_klist. At this point we won't 430 * report any more events, and there are nasty race conditions that 431 * can beat us if we don't. 432 */ 433 knlist_clear(&p->p_klist, 1); 434 435 /* 436 * Notify parent that we're gone. If parent has the PS_NOCLDWAIT 437 * flag set, or if the handler is set to SIG_IGN, notify process 438 * 1 instead (and hope it will handle this situation). 439 */ 440 PROC_LOCK(p->p_pptr); 441 mtx_lock(&p->p_pptr->p_sigacts->ps_mtx); 442 if (p->p_pptr->p_sigacts->ps_flag & (PS_NOCLDWAIT | PS_CLDSIGIGN)) { 443 struct proc *pp; 444 445 mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx); 446 pp = p->p_pptr; 447 PROC_UNLOCK(pp); 448 proc_reparent(p, initproc); 449 p->p_sigparent = SIGCHLD; 450 PROC_LOCK(p->p_pptr); 451 /* 452 * If this was the last child of our parent, notify 453 * parent, so in case he was wait(2)ing, he will 454 * continue. 455 */ 456 if (LIST_EMPTY(&pp->p_children)) 457 wakeup(pp); 458 } else 459 mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx); 460 461 if (p->p_pptr == initproc) 462 psignal(p->p_pptr, SIGCHLD); 463 else if (p->p_sigparent != 0) 464 psignal(p->p_pptr, p->p_sigparent); 465 PROC_UNLOCK(p->p_pptr); 466 467 /* 468 * If this is a kthread, then wakeup anyone waiting for it to exit. 469 */ 470 if (p->p_flag & P_KTHREAD) 471 wakeup(p); 472 PROC_UNLOCK(p); 473 474 /* 475 * Finally, call machine-dependent code to release the remaining 476 * resources including address space. 477 * The address space is released by "vmspace_exitfree(p)" in 478 * vm_waitproc(). 479 */ 480 cpu_exit(td); 481 482 PROC_LOCK(p); 483 PROC_LOCK(p->p_pptr); 484 sx_xunlock(&proctree_lock); 485 486 /* 487 * We have to wait until after acquiring all locks before 488 * changing p_state. We need to avoid all possible context 489 * switches (including ones from blocking on a mutex) while 490 * marked as a zombie. 491 */ 492 mtx_lock_spin(&sched_lock); 493 p->p_state = PRS_ZOMBIE; 494 495 critical_enter(); 496 mtx_unlock_spin(&sched_lock); 497 wakeup(p->p_pptr); 498 PROC_UNLOCK(p->p_pptr); 499 mtx_lock_spin(&sched_lock); 500 critical_exit(); 501 502 /* Do the same timestamp bookkeeping that mi_switch() would do. */ 503 binuptime(&new_switchtime); 504 bintime_add(&p->p_rux.rux_runtime, &new_switchtime); 505 bintime_sub(&p->p_rux.rux_runtime, PCPU_PTR(switchtime)); 506 PCPU_SET(switchtime, new_switchtime); 507 PCPU_SET(switchticks, ticks); 508 cnt.v_swtch++; 509 510 sched_exit(p->p_pptr, td); 511 512 /* 513 * Hopefully no one will try to deliver a signal to the process this 514 * late in the game. 515 */ 516 knlist_destroy(&p->p_klist); 517 518 /* 519 * Make sure the scheduler takes this thread out of its tables etc. 520 * This will also release this thread's reference to the ucred. 521 * Other thread parts to release include pcb bits and such. 522 */ 523 thread_exit(); 524 } 525 526 #ifdef COMPAT_43 527 /* 528 * The dirty work is handled by kern_wait(). 529 * 530 * MPSAFE. 531 */ 532 int 533 owait(struct thread *td, struct owait_args *uap __unused) 534 { 535 int error, status; 536 537 error = kern_wait(td, WAIT_ANY, &status, 0, NULL); 538 if (error == 0) 539 td->td_retval[1] = status; 540 return (error); 541 } 542 #endif /* COMPAT_43 */ 543 544 /* 545 * The dirty work is handled by kern_wait(). 546 * 547 * MPSAFE. 548 */ 549 int 550 wait4(struct thread *td, struct wait_args *uap) 551 { 552 struct rusage ru, *rup; 553 int error, status; 554 555 if (uap->rusage != NULL) 556 rup = &ru; 557 else 558 rup = NULL; 559 error = kern_wait(td, uap->pid, &status, uap->options, rup); 560 if (uap->status != NULL && error == 0) 561 error = copyout(&status, uap->status, sizeof(status)); 562 if (uap->rusage != NULL && error == 0) 563 error = copyout(&ru, uap->rusage, sizeof(struct rusage)); 564 return (error); 565 } 566 567 int 568 kern_wait(struct thread *td, pid_t pid, int *status, int options, 569 struct rusage *rusage) 570 { 571 struct proc *p, *q, *t; 572 int error, nfound; 573 574 q = td->td_proc; 575 if (pid == 0) { 576 PROC_LOCK(q); 577 pid = -q->p_pgid; 578 PROC_UNLOCK(q); 579 } 580 if (options &~ (WUNTRACED|WNOHANG|WCONTINUED|WLINUXCLONE)) 581 return (EINVAL); 582 loop: 583 nfound = 0; 584 sx_xlock(&proctree_lock); 585 LIST_FOREACH(p, &q->p_children, p_sibling) { 586 PROC_LOCK(p); 587 if (pid != WAIT_ANY && 588 p->p_pid != pid && p->p_pgid != -pid) { 589 PROC_UNLOCK(p); 590 continue; 591 } 592 593 /* 594 * This special case handles a kthread spawned by linux_clone 595 * (see linux_misc.c). The linux_wait4 and linux_waitpid 596 * functions need to be able to distinguish between waiting 597 * on a process and waiting on a thread. It is a thread if 598 * p_sigparent is not SIGCHLD, and the WLINUXCLONE option 599 * signifies we want to wait for threads and not processes. 600 */ 601 if ((p->p_sigparent != SIGCHLD) ^ 602 ((options & WLINUXCLONE) != 0)) { 603 PROC_UNLOCK(p); 604 continue; 605 } 606 607 nfound++; 608 if (p->p_state == PRS_ZOMBIE) { 609 td->td_retval[0] = p->p_pid; 610 if (status) 611 *status = p->p_xstat; /* convert to int */ 612 if (rusage) { 613 *rusage = *p->p_ru; 614 calcru(p, &rusage->ru_utime, &rusage->ru_stime); 615 } 616 617 /* 618 * If we got the child via a ptrace 'attach', 619 * we need to give it back to the old parent. 620 */ 621 PROC_UNLOCK(p); 622 if (p->p_oppid && (t = pfind(p->p_oppid)) != NULL) { 623 PROC_LOCK(p); 624 p->p_oppid = 0; 625 proc_reparent(p, t); 626 PROC_UNLOCK(p); 627 psignal(t, SIGCHLD); 628 wakeup(t); 629 PROC_UNLOCK(t); 630 sx_xunlock(&proctree_lock); 631 return (0); 632 } 633 634 /* 635 * Remove other references to this process to ensure 636 * we have an exclusive reference. 637 */ 638 sx_xlock(&allproc_lock); 639 LIST_REMOVE(p, p_list); /* off zombproc */ 640 sx_xunlock(&allproc_lock); 641 LIST_REMOVE(p, p_sibling); 642 leavepgrp(p); 643 sx_xunlock(&proctree_lock); 644 645 /* 646 * As a side effect of this lock, we know that 647 * all other writes to this proc are visible now, so 648 * no more locking is needed for p. 649 */ 650 PROC_LOCK(p); 651 p->p_xstat = 0; /* XXX: why? */ 652 PROC_UNLOCK(p); 653 PROC_LOCK(q); 654 ruadd(&q->p_stats->p_cru, &q->p_crux, p->p_ru, 655 &p->p_rux); 656 PROC_UNLOCK(q); 657 FREE(p->p_ru, M_ZOMBIE); 658 p->p_ru = NULL; 659 660 /* 661 * Decrement the count of procs running with this uid. 662 */ 663 (void)chgproccnt(p->p_ucred->cr_ruidinfo, -1, 0); 664 665 /* 666 * Free credentials, arguments, and sigacts. 667 */ 668 crfree(p->p_ucred); 669 p->p_ucred = NULL; 670 pargs_drop(p->p_args); 671 p->p_args = NULL; 672 sigacts_free(p->p_sigacts); 673 p->p_sigacts = NULL; 674 675 /* 676 * Do any thread-system specific cleanups. 677 */ 678 thread_wait(p); 679 680 /* 681 * Give vm and machine-dependent layer a chance 682 * to free anything that cpu_exit couldn't 683 * release while still running in process context. 684 */ 685 vm_waitproc(p); 686 #ifdef MAC 687 mac_destroy_proc(p); 688 #endif 689 KASSERT(FIRST_THREAD_IN_PROC(p), 690 ("kern_wait: no residual thread!")); 691 uma_zfree(proc_zone, p); 692 sx_xlock(&allproc_lock); 693 nprocs--; 694 sx_xunlock(&allproc_lock); 695 return (0); 696 } 697 mtx_lock_spin(&sched_lock); 698 if (P_SHOULDSTOP(p) && p->p_suspcount == p->p_numthreads && 699 (p->p_flag & P_WAITED) == 0 && 700 (p->p_flag & P_TRACED || options & WUNTRACED)) { 701 mtx_unlock_spin(&sched_lock); 702 p->p_flag |= P_WAITED; 703 sx_xunlock(&proctree_lock); 704 td->td_retval[0] = p->p_pid; 705 if (status) 706 *status = W_STOPCODE(p->p_xstat); 707 PROC_UNLOCK(p); 708 return (0); 709 } 710 mtx_unlock_spin(&sched_lock); 711 if (options & WCONTINUED && (p->p_flag & P_CONTINUED)) { 712 sx_xunlock(&proctree_lock); 713 td->td_retval[0] = p->p_pid; 714 p->p_flag &= ~P_CONTINUED; 715 PROC_UNLOCK(p); 716 717 if (status) 718 *status = SIGCONT; 719 return (0); 720 } 721 PROC_UNLOCK(p); 722 } 723 if (nfound == 0) { 724 sx_xunlock(&proctree_lock); 725 return (ECHILD); 726 } 727 if (options & WNOHANG) { 728 sx_xunlock(&proctree_lock); 729 td->td_retval[0] = 0; 730 return (0); 731 } 732 PROC_LOCK(q); 733 sx_xunlock(&proctree_lock); 734 error = msleep(q, &q->p_mtx, PWAIT | PCATCH, "wait", 0); 735 PROC_UNLOCK(q); 736 if (error) 737 return (error); 738 goto loop; 739 } 740 741 /* 742 * Make process 'parent' the new parent of process 'child'. 743 * Must be called with an exclusive hold of proctree lock. 744 */ 745 void 746 proc_reparent(struct proc *child, struct proc *parent) 747 { 748 749 sx_assert(&proctree_lock, SX_XLOCKED); 750 PROC_LOCK_ASSERT(child, MA_OWNED); 751 if (child->p_pptr == parent) 752 return; 753 754 LIST_REMOVE(child, p_sibling); 755 LIST_INSERT_HEAD(&parent->p_children, child, p_sibling); 756 child->p_pptr = parent; 757 } 758