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 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)kern_exit.c 8.7 (Berkeley) 2/12/94 39 */ 40 41 #include <sys/cdefs.h> 42 __FBSDID("$FreeBSD$"); 43 44 #include "opt_compat.h" 45 #include "opt_ktrace.h" 46 #include "opt_mac.h" 47 48 #include <sys/param.h> 49 #include <sys/systm.h> 50 #include <sys/sysproto.h> 51 #include <sys/eventhandler.h> 52 #include <sys/kernel.h> 53 #include <sys/malloc.h> 54 #include <sys/lock.h> 55 #include <sys/mutex.h> 56 #include <sys/proc.h> 57 #include <sys/pioctl.h> 58 #include <sys/tty.h> 59 #include <sys/wait.h> 60 #include <sys/vmmeter.h> 61 #include <sys/vnode.h> 62 #include <sys/resourcevar.h> 63 #include <sys/signalvar.h> 64 #include <sys/sched.h> 65 #include <sys/sx.h> 66 #include <sys/ptrace.h> 67 #include <sys/acct.h> /* for acct_process() function prototype */ 68 #include <sys/filedesc.h> 69 #include <sys/mac.h> 70 #include <sys/shm.h> 71 #include <sys/sem.h> 72 #ifdef KTRACE 73 #include <sys/ktrace.h> 74 #endif 75 76 #include <vm/vm.h> 77 #include <vm/vm_extern.h> 78 #include <vm/vm_param.h> 79 #include <vm/pmap.h> 80 #include <vm/vm_map.h> 81 #include <vm/vm_page.h> 82 #include <vm/uma.h> 83 #include <sys/user.h> 84 85 /* Required to be non-static for SysVR4 emulator */ 86 MALLOC_DEFINE(M_ZOMBIE, "zombie", "zombie proc status"); 87 88 static int wait1(struct thread *, struct wait_args *, int); 89 90 /* 91 * exit -- 92 * Death of process. 93 * 94 * MPSAFE 95 */ 96 void 97 sys_exit(struct thread *td, struct sys_exit_args *uap) 98 { 99 100 mtx_lock(&Giant); 101 exit1(td, W_EXITCODE(uap->rval, 0)); 102 /* NOTREACHED */ 103 } 104 105 /* 106 * Exit: deallocate address space and other resources, change proc state 107 * to zombie, and unlink proc from allproc and parent's lists. Save exit 108 * status and rusage for wait(). Check for child processes and orphan them. 109 */ 110 void 111 exit1(struct thread *td, int rv) 112 { 113 struct proc *p, *nq, *q; 114 struct tty *tp; 115 struct vnode *ttyvp; 116 struct vmspace *vm; 117 struct vnode *vtmp; 118 #ifdef KTRACE 119 struct vnode *tracevp; 120 struct ucred *tracecred; 121 #endif 122 struct plimit *plim; 123 124 GIANT_REQUIRED; 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_SA || p->p_numthreads > 1) { 138 /* 139 * First check if some other thread got here before us.. 140 * if so, act apropriatly, (exit or suspend); 141 */ 142 thread_suspend_check(0); 143 144 /* 145 * Kill off the other threads. This requires 146 * Some co-operation from other parts of the kernel 147 * so it may not be instant. 148 * 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 immediatly 152 * with EINTR or EWOULDBLOCK, which will hopefully force them 153 * to back out to userland, freeing resources as they go, and 154 * anything attempting to return to userland will thread_exit() 155 * from userret(). thread_exit() will unsuspend us 156 * when the last other thread exits. 157 */ 158 if (thread_single(SINGLE_EXIT)) { 159 panic ("Exit: Single threading fouled up"); 160 } 161 /* 162 * All other activity in this process is now stopped. 163 * Remove excess KSEs and KSEGRPS. XXXKSE (when we have them) 164 * ... 165 * Turn off threading support. 166 */ 167 p->p_flag &= ~P_SA; 168 thread_single_end(); /* Don't need this any more. */ 169 } 170 /* 171 * With this state set: 172 * Any thread entering the kernel from userspace will thread_exit() 173 * in trap(). Any thread attempting to sleep will return immediatly 174 * with EINTR or EWOULDBLOCK, which will hopefully force them 175 * to back out to userland, freeing resources as they go, and 176 * anything attempting to return to userland will thread_exit() 177 * from userret(). thread_exit() will do a wakeup on p->p_numthreads 178 * if it transitions to 1. 179 */ 180 181 p->p_flag |= P_WEXIT; 182 PROC_UNLOCK(p); 183 184 /* Are we a task leader? */ 185 if (p == p->p_leader) { 186 mtx_lock(&ppeers_lock); 187 q = p->p_peers; 188 while (q != NULL) { 189 PROC_LOCK(q); 190 psignal(q, SIGKILL); 191 PROC_UNLOCK(q); 192 q = q->p_peers; 193 } 194 while (p->p_peers != NULL) 195 msleep(p, &ppeers_lock, PWAIT, "exit1", 0); 196 mtx_unlock(&ppeers_lock); 197 } 198 199 #ifdef PGINPROF 200 vmsizmon(); 201 #endif 202 STOPEVENT(p, S_EXIT, rv); 203 wakeup(&p->p_stype); /* Wakeup anyone in procfs' PIOCWAIT */ 204 205 /* 206 * Check if any loadable modules need anything done at process exit. 207 * e.g. SYSV IPC stuff 208 * XXX what if one of these generates an error? 209 */ 210 EVENTHANDLER_INVOKE(process_exit, p); 211 212 MALLOC(p->p_ru, struct rusage *, sizeof(struct rusage), 213 M_ZOMBIE, M_WAITOK); 214 /* 215 * If parent is waiting for us to exit or exec, 216 * P_PPWAIT is set; we will wakeup the parent below. 217 */ 218 PROC_LOCK(p); 219 stopprofclock(p); 220 p->p_flag &= ~(P_TRACED | P_PPWAIT); 221 SIGEMPTYSET(p->p_siglist); 222 SIGEMPTYSET(td->td_siglist); 223 224 /* 225 * Stop the real interval timer. If the handler is currently 226 * executing, prevent it from rearming itself and let it finish. 227 */ 228 if (timevalisset(&p->p_realtimer.it_value) && 229 callout_stop(&p->p_itcallout) == 0) { 230 timevalclear(&p->p_realtimer.it_interval); 231 msleep(&p->p_itcallout, &p->p_mtx, PWAIT, "ritwait", 0); 232 KASSERT(!timevalisset(&p->p_realtimer.it_value), 233 ("realtime timer is still armed")); 234 } 235 PROC_UNLOCK(p); 236 237 /* 238 * Reset any sigio structures pointing to us as a result of 239 * F_SETOWN with our pid. 240 */ 241 funsetownlst(&p->p_sigiolst); 242 243 /* 244 * Close open files and release open-file table. 245 * This may block! 246 */ 247 fdfree(td); 248 249 /* 250 * Remove ourself from our leader's peer list and wake our leader. 251 */ 252 mtx_lock(&ppeers_lock); 253 if (p->p_leader->p_peers) { 254 q = p->p_leader; 255 while (q->p_peers != p) 256 q = q->p_peers; 257 q->p_peers = p->p_peers; 258 wakeup(p->p_leader); 259 } 260 mtx_unlock(&ppeers_lock); 261 262 /* The next two chunks should probably be moved to vmspace_exit. */ 263 vm = p->p_vmspace; 264 /* 265 * Release user portion of address space. 266 * This releases references to vnodes, 267 * which could cause I/O if the file has been unlinked. 268 * Need to do this early enough that we can still sleep. 269 * Can't free the entire vmspace as the kernel stack 270 * may be mapped within that space also. 271 * 272 * Processes sharing the same vmspace may exit in one order, and 273 * get cleaned up by vmspace_exit() in a different order. The 274 * last exiting process to reach this point releases as much of 275 * the environment as it can, and the last process cleaned up 276 * by vmspace_exit() (which decrements exitingcnt) cleans up the 277 * remainder. 278 */ 279 ++vm->vm_exitingcnt; 280 if (--vm->vm_refcnt == 0) { 281 shmexit(vm); 282 vm_page_lock_queues(); 283 pmap_remove_pages(vmspace_pmap(vm), vm_map_min(&vm->vm_map), 284 vm_map_max(&vm->vm_map)); 285 vm_page_unlock_queues(); 286 (void) vm_map_remove(&vm->vm_map, vm_map_min(&vm->vm_map), 287 vm_map_max(&vm->vm_map)); 288 } 289 290 sx_xlock(&proctree_lock); 291 if (SESS_LEADER(p)) { 292 struct session *sp; 293 294 sp = p->p_session; 295 if (sp->s_ttyvp) { 296 /* 297 * Controlling process. 298 * Signal foreground pgrp, 299 * drain controlling terminal 300 * and revoke access to controlling terminal. 301 */ 302 if (sp->s_ttyp && (sp->s_ttyp->t_session == sp)) { 303 tp = sp->s_ttyp; 304 if (sp->s_ttyp->t_pgrp) { 305 PGRP_LOCK(sp->s_ttyp->t_pgrp); 306 pgsignal(sp->s_ttyp->t_pgrp, SIGHUP, 1); 307 PGRP_UNLOCK(sp->s_ttyp->t_pgrp); 308 } 309 /* XXX tp should be locked. */ 310 sx_xunlock(&proctree_lock); 311 (void) ttywait(tp); 312 sx_xlock(&proctree_lock); 313 /* 314 * The tty could have been revoked 315 * if we blocked. 316 */ 317 if (sp->s_ttyvp) { 318 ttyvp = sp->s_ttyvp; 319 SESS_LOCK(p->p_session); 320 sp->s_ttyvp = NULL; 321 SESS_UNLOCK(p->p_session); 322 sx_xunlock(&proctree_lock); 323 VOP_REVOKE(ttyvp, REVOKEALL); 324 vrele(ttyvp); 325 sx_xlock(&proctree_lock); 326 } 327 } 328 if (sp->s_ttyvp) { 329 ttyvp = sp->s_ttyvp; 330 SESS_LOCK(p->p_session); 331 sp->s_ttyvp = NULL; 332 SESS_UNLOCK(p->p_session); 333 vrele(ttyvp); 334 } 335 /* 336 * s_ttyp is not zero'd; we use this to indicate 337 * that the session once had a controlling terminal. 338 * (for logging and informational purposes) 339 */ 340 } 341 SESS_LOCK(p->p_session); 342 sp->s_leader = NULL; 343 SESS_UNLOCK(p->p_session); 344 } 345 fixjobc(p, p->p_pgrp, 0); 346 sx_xunlock(&proctree_lock); 347 (void)acct_process(td); 348 #ifdef KTRACE 349 /* 350 * release trace file 351 */ 352 PROC_LOCK(p); 353 mtx_lock(&ktrace_mtx); 354 p->p_traceflag = 0; /* don't trace the vrele() */ 355 tracevp = p->p_tracevp; 356 p->p_tracevp = NULL; 357 tracecred = p->p_tracecred; 358 p->p_tracecred = NULL; 359 mtx_unlock(&ktrace_mtx); 360 PROC_UNLOCK(p); 361 if (tracevp != NULL) 362 vrele(tracevp); 363 if (tracecred != NULL) 364 crfree(tracecred); 365 #endif 366 /* 367 * Release reference to text vnode 368 */ 369 if ((vtmp = p->p_textvp) != NULL) { 370 p->p_textvp = NULL; 371 vrele(vtmp); 372 } 373 374 /* 375 * Release our limits structure. 376 */ 377 PROC_LOCK(p); 378 plim = p->p_limit; 379 p->p_limit = NULL; 380 PROC_UNLOCK(p); 381 lim_free(plim); 382 383 /* 384 * Release this thread's reference to the ucred. The actual proc 385 * reference will stay around until the proc is harvested by 386 * wait(). At this point the ucred is immutable (no other threads 387 * from this proc are around that can change it) so we leave the 388 * per-thread ucred pointer intact in case it is needed although 389 * in theory nothing should be using it at this point. 390 */ 391 crfree(td->td_ucred); 392 393 /* 394 * Remove proc from allproc queue and pidhash chain. 395 * Place onto zombproc. Unlink from parent's child list. 396 */ 397 sx_xlock(&allproc_lock); 398 LIST_REMOVE(p, p_list); 399 LIST_INSERT_HEAD(&zombproc, p, p_list); 400 LIST_REMOVE(p, p_hash); 401 sx_xunlock(&allproc_lock); 402 403 sx_xlock(&proctree_lock); 404 q = LIST_FIRST(&p->p_children); 405 if (q != NULL) /* only need this if any child is S_ZOMB */ 406 wakeup(initproc); 407 for (; q != NULL; q = nq) { 408 nq = LIST_NEXT(q, p_sibling); 409 PROC_LOCK(q); 410 proc_reparent(q, initproc); 411 q->p_sigparent = SIGCHLD; 412 /* 413 * Traced processes are killed 414 * since their existence means someone is screwing up. 415 */ 416 if (q->p_flag & P_TRACED) { 417 q->p_flag &= ~P_TRACED; 418 psignal(q, SIGKILL); 419 } 420 PROC_UNLOCK(q); 421 } 422 423 /* 424 * Save exit status and final rusage info, adding in child rusage 425 * info and self times. 426 */ 427 PROC_LOCK(p); 428 p->p_xstat = rv; 429 *p->p_ru = p->p_stats->p_ru; 430 mtx_lock_spin(&sched_lock); 431 calcru(p, &p->p_ru->ru_utime, &p->p_ru->ru_stime, NULL); 432 mtx_unlock_spin(&sched_lock); 433 ruadd(p->p_ru, &p->p_stats->p_cru); 434 435 /* 436 * Notify interested parties of our demise. 437 */ 438 KNOTE(&p->p_klist, NOTE_EXIT); 439 /* 440 * Just delete all entries in the p_klist. At this point we won't 441 * report any more events, and there are nasty race conditions that 442 * can beat us if we don't. 443 */ 444 while (SLIST_FIRST(&p->p_klist)) 445 SLIST_REMOVE_HEAD(&p->p_klist, kn_selnext); 446 447 /* 448 * Notify parent that we're gone. If parent has the PS_NOCLDWAIT 449 * flag set, or if the handler is set to SIG_IGN, notify process 450 * 1 instead (and hope it will handle this situation). 451 */ 452 PROC_LOCK(p->p_pptr); 453 mtx_lock(&p->p_pptr->p_sigacts->ps_mtx); 454 if (p->p_pptr->p_sigacts->ps_flag & (PS_NOCLDWAIT | PS_CLDSIGIGN)) { 455 struct proc *pp; 456 457 mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx); 458 pp = p->p_pptr; 459 PROC_UNLOCK(pp); 460 proc_reparent(p, initproc); 461 p->p_sigparent = SIGCHLD; 462 PROC_LOCK(p->p_pptr); 463 /* 464 * If this was the last child of our parent, notify 465 * parent, so in case he was wait(2)ing, he will 466 * continue. 467 */ 468 if (LIST_EMPTY(&pp->p_children)) 469 wakeup(pp); 470 } else 471 mtx_unlock(&p->p_pptr->p_sigacts->ps_mtx); 472 473 if (p->p_pptr == initproc) 474 psignal(p->p_pptr, SIGCHLD); 475 else if (p->p_sigparent != 0) 476 psignal(p->p_pptr, p->p_sigparent); 477 PROC_UNLOCK(p->p_pptr); 478 479 /* 480 * If this is a kthread, then wakeup anyone waiting for it to exit. 481 */ 482 if (p->p_flag & P_KTHREAD) 483 wakeup(p); 484 PROC_UNLOCK(p); 485 486 /* 487 * Finally, call machine-dependent code to release the remaining 488 * resources including address space. 489 * The address space is released by "vmspace_exitfree(p)" in 490 * vm_waitproc(). 491 */ 492 cpu_exit(td); 493 494 PROC_LOCK(p); 495 PROC_LOCK(p->p_pptr); 496 sx_xunlock(&proctree_lock); 497 mtx_lock_spin(&sched_lock); 498 499 while (mtx_owned(&Giant)) 500 mtx_unlock(&Giant); 501 502 /* 503 * We have to wait until after acquiring all locks before 504 * changing p_state. If we block on a mutex then we will be 505 * back at SRUN when we resume and our parent will never 506 * harvest us. 507 */ 508 p->p_state = PRS_ZOMBIE; 509 510 wakeup(p->p_pptr); 511 PROC_UNLOCK(p->p_pptr); 512 cnt.v_swtch++; 513 binuptime(PCPU_PTR(switchtime)); 514 PCPU_SET(switchticks, ticks); 515 516 cpu_sched_exit(td); /* XXXKSE check if this should be in thread_exit */ 517 /* 518 * Allow the scheduler to adjust the priority of the 519 * parent when a kseg is exiting. 520 */ 521 if (p->p_pid != 1) 522 sched_exit(p->p_pptr, p); 523 524 /* 525 * Make sure the scheduler takes this thread out of its tables etc. 526 * This will also release this thread's reference to the ucred. 527 * Other thread parts to release include pcb bits and such. 528 */ 529 thread_exit(); 530 } 531 532 #ifdef COMPAT_43 533 /* 534 * MPSAFE. The dirty work is handled by wait1(). 535 */ 536 int 537 owait(struct thread *td, struct owait_args *uap __unused) 538 { 539 struct wait_args w; 540 541 w.options = 0; 542 w.rusage = NULL; 543 w.pid = WAIT_ANY; 544 w.status = NULL; 545 return (wait1(td, &w, 1)); 546 } 547 #endif /* COMPAT_43 */ 548 549 /* 550 * MPSAFE. The dirty work is handled by wait1(). 551 */ 552 int 553 wait4(struct thread *td, struct wait_args *uap) 554 { 555 556 return (wait1(td, uap, 0)); 557 } 558 559 /* 560 * MPSAFE 561 */ 562 static int 563 wait1(struct thread *td, struct wait_args *uap, int compat) 564 { 565 struct rusage ru; 566 int nfound; 567 struct proc *p, *q, *t; 568 int status, error; 569 570 q = td->td_proc; 571 if (uap->pid == 0) { 572 PROC_LOCK(q); 573 uap->pid = -q->p_pgid; 574 PROC_UNLOCK(q); 575 } 576 if (uap->options &~ (WUNTRACED|WNOHANG|WCONTINUED|WLINUXCLONE)) 577 return (EINVAL); 578 mtx_lock(&Giant); 579 loop: 580 nfound = 0; 581 sx_xlock(&proctree_lock); 582 LIST_FOREACH(p, &q->p_children, p_sibling) { 583 PROC_LOCK(p); 584 if (uap->pid != WAIT_ANY && 585 p->p_pid != uap->pid && p->p_pgid != -uap->pid) { 586 PROC_UNLOCK(p); 587 continue; 588 } 589 590 /* 591 * This special case handles a kthread spawned by linux_clone 592 * (see linux_misc.c). The linux_wait4 and linux_waitpid 593 * functions need to be able to distinguish between waiting 594 * on a process and waiting on a thread. It is a thread if 595 * p_sigparent is not SIGCHLD, and the WLINUXCLONE option 596 * signifies we want to wait for threads and not processes. 597 */ 598 if ((p->p_sigparent != SIGCHLD) ^ 599 ((uap->options & WLINUXCLONE) != 0)) { 600 PROC_UNLOCK(p); 601 continue; 602 } 603 604 nfound++; 605 if (p->p_state == PRS_ZOMBIE) { 606 td->td_retval[0] = p->p_pid; 607 #ifdef COMPAT_43 608 if (compat) 609 td->td_retval[1] = p->p_xstat; 610 else 611 #endif 612 if (uap->status) { 613 status = p->p_xstat; /* convert to int */ 614 PROC_UNLOCK(p); 615 if ((error = copyout(&status, 616 uap->status, sizeof(status)))) { 617 sx_xunlock(&proctree_lock); 618 mtx_unlock(&Giant); 619 return (error); 620 } 621 PROC_LOCK(p); 622 } 623 if (uap->rusage) { 624 bcopy(p->p_ru, &ru, sizeof(ru)); 625 PROC_UNLOCK(p); 626 if ((error = copyout(&ru, 627 uap->rusage, sizeof (struct rusage)))) { 628 sx_xunlock(&proctree_lock); 629 mtx_unlock(&Giant); 630 return (error); 631 } 632 } else 633 PROC_UNLOCK(p); 634 /* 635 * If we got the child via a ptrace 'attach', 636 * we need to give it back to the old parent. 637 */ 638 if (p->p_oppid && (t = pfind(p->p_oppid)) != NULL) { 639 PROC_LOCK(p); 640 p->p_oppid = 0; 641 proc_reparent(p, t); 642 PROC_UNLOCK(p); 643 psignal(t, SIGCHLD); 644 wakeup(t); 645 PROC_UNLOCK(t); 646 sx_xunlock(&proctree_lock); 647 mtx_unlock(&Giant); 648 return (0); 649 } 650 651 /* 652 * Remove other references to this process to ensure 653 * we have an exclusive reference. 654 */ 655 sx_xlock(&allproc_lock); 656 LIST_REMOVE(p, p_list); /* off zombproc */ 657 sx_xunlock(&allproc_lock); 658 LIST_REMOVE(p, p_sibling); 659 leavepgrp(p); 660 sx_xunlock(&proctree_lock); 661 662 /* 663 * As a side effect of this lock, we know that 664 * all other writes to this proc are visible now, so 665 * no more locking is needed for p. 666 */ 667 PROC_LOCK(p); 668 p->p_xstat = 0; /* XXX: why? */ 669 PROC_UNLOCK(p); 670 PROC_LOCK(q); 671 ruadd(&q->p_stats->p_cru, p->p_ru); 672 PROC_UNLOCK(q); 673 FREE(p->p_ru, M_ZOMBIE); 674 p->p_ru = NULL; 675 676 /* 677 * Decrement the count of procs running with this uid. 678 */ 679 (void)chgproccnt(p->p_ucred->cr_ruidinfo, -1, 0); 680 681 /* 682 * Free credentials, arguments, and sigacts 683 */ 684 crfree(p->p_ucred); 685 p->p_ucred = NULL; 686 pargs_drop(p->p_args); 687 p->p_args = NULL; 688 sigacts_free(p->p_sigacts); 689 p->p_sigacts = NULL; 690 691 /* 692 * do any thread-system specific cleanups 693 */ 694 thread_wait(p); 695 696 /* 697 * Give vm and machine-dependent layer a chance 698 * to free anything that cpu_exit couldn't 699 * release while still running in process context. 700 */ 701 vm_waitproc(p); 702 #ifdef MAC 703 mac_destroy_proc(p); 704 #endif 705 KASSERT(FIRST_THREAD_IN_PROC(p), 706 ("wait1: no residual thread!")); 707 uma_zfree(proc_zone, p); 708 sx_xlock(&allproc_lock); 709 nprocs--; 710 sx_xunlock(&allproc_lock); 711 mtx_unlock(&Giant); 712 return (0); 713 } 714 mtx_lock_spin(&sched_lock); 715 if (P_SHOULDSTOP(p) && (p->p_suspcount == p->p_numthreads) && 716 ((p->p_flag & P_WAITED) == 0) && 717 (p->p_flag & P_TRACED || uap->options & WUNTRACED)) { 718 mtx_unlock_spin(&sched_lock); 719 p->p_flag |= P_WAITED; 720 sx_xunlock(&proctree_lock); 721 td->td_retval[0] = p->p_pid; 722 #ifdef COMPAT_43 723 if (compat) { 724 td->td_retval[1] = W_STOPCODE(p->p_xstat); 725 PROC_UNLOCK(p); 726 error = 0; 727 } else 728 #endif 729 if (uap->status) { 730 status = W_STOPCODE(p->p_xstat); 731 PROC_UNLOCK(p); 732 error = copyout(&status, 733 uap->status, sizeof(status)); 734 } else { 735 PROC_UNLOCK(p); 736 error = 0; 737 } 738 mtx_unlock(&Giant); 739 return (error); 740 } 741 mtx_unlock_spin(&sched_lock); 742 if (uap->options & WCONTINUED && (p->p_flag & P_CONTINUED)) { 743 sx_xunlock(&proctree_lock); 744 td->td_retval[0] = p->p_pid; 745 p->p_flag &= ~P_CONTINUED; 746 PROC_UNLOCK(p); 747 748 if (uap->status) { 749 status = SIGCONT; 750 error = copyout(&status, 751 uap->status, sizeof(status)); 752 } else 753 error = 0; 754 755 mtx_unlock(&Giant); 756 return (error); 757 } 758 PROC_UNLOCK(p); 759 } 760 if (nfound == 0) { 761 sx_xunlock(&proctree_lock); 762 mtx_unlock(&Giant); 763 return (ECHILD); 764 } 765 if (uap->options & WNOHANG) { 766 sx_xunlock(&proctree_lock); 767 td->td_retval[0] = 0; 768 mtx_unlock(&Giant); 769 return (0); 770 } 771 PROC_LOCK(q); 772 sx_xunlock(&proctree_lock); 773 error = msleep(q, &q->p_mtx, PWAIT | PCATCH, "wait", 0); 774 PROC_UNLOCK(q); 775 if (error) { 776 mtx_unlock(&Giant); 777 return (error); 778 } 779 goto loop; 780 } 781 782 /* 783 * Make process 'parent' the new parent of process 'child'. 784 * Must be called with an exclusive hold of proctree lock. 785 */ 786 void 787 proc_reparent(struct proc *child, struct proc *parent) 788 { 789 790 sx_assert(&proctree_lock, SX_XLOCKED); 791 PROC_LOCK_ASSERT(child, MA_OWNED); 792 if (child->p_pptr == parent) 793 return; 794 795 LIST_REMOVE(child, p_sibling); 796 LIST_INSERT_HEAD(&parent->p_children, child, p_sibling); 797 child->p_pptr = parent; 798 } 799