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 * $FreeBSD$ 40 */ 41 42 #include "opt_compat.h" 43 #include "opt_ktrace.h" 44 #include "opt_mac.h" 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/sysproto.h> 49 #include <sys/eventhandler.h> 50 #include <sys/kernel.h> 51 #include <sys/malloc.h> 52 #include <sys/lock.h> 53 #include <sys/mutex.h> 54 #include <sys/proc.h> 55 #include <sys/pioctl.h> 56 #include <sys/tty.h> 57 #include <sys/wait.h> 58 #include <sys/vmmeter.h> 59 #include <sys/vnode.h> 60 #include <sys/resourcevar.h> 61 #include <sys/signalvar.h> 62 #include <sys/sched.h> 63 #include <sys/sx.h> 64 #include <sys/ptrace.h> 65 #include <sys/acct.h> /* for acct_process() function prototype */ 66 #include <sys/filedesc.h> 67 #include <sys/mac.h> 68 #include <sys/shm.h> 69 #include <sys/sem.h> 70 #include <sys/jail.h> 71 #ifdef KTRACE 72 #include <sys/ktrace.h> 73 #endif 74 75 #include <vm/vm.h> 76 #include <vm/vm_extern.h> 77 #include <vm/vm_param.h> 78 #include <vm/pmap.h> 79 #include <vm/vm_map.h> 80 #include <vm/vm_page.h> 81 #include <vm/uma.h> 82 #include <sys/user.h> 83 84 /* Required to be non-static for SysVR4 emulator */ 85 MALLOC_DEFINE(M_ZOMBIE, "zombie", "zombie proc status"); 86 87 static int wait1(struct thread *, struct wait_args *, int); 88 89 /* 90 * exit -- 91 * Death of process. 92 * 93 * MPSAFE 94 */ 95 void 96 sys_exit(struct thread *td, struct sys_exit_args *uap) 97 { 98 99 mtx_lock(&Giant); 100 exit1(td, W_EXITCODE(uap->rval, 0)); 101 /* NOTREACHED */ 102 } 103 104 /* 105 * Exit: deallocate address space and other resources, change proc state 106 * to zombie, and unlink proc from allproc and parent's lists. Save exit 107 * status and rusage for wait(). Check for child processes and orphan them. 108 */ 109 void 110 exit1(struct thread *td, int rv) 111 { 112 struct proc *p, *nq, *q; 113 struct tty *tp; 114 struct vnode *ttyvp; 115 struct vmspace *vm; 116 struct vnode *vtmp; 117 #ifdef KTRACE 118 struct vnode *tracevp; 119 struct ucred *tracecred; 120 #endif 121 122 GIANT_REQUIRED; 123 124 p = td->td_proc; 125 if (p == initproc) { 126 printf("init died (signal %d, exit %d)\n", 127 WTERMSIG(rv), WEXITSTATUS(rv)); 128 panic("Going nowhere without my init!"); 129 } 130 131 /* 132 * MUST abort all other threads before proceeding past here. 133 */ 134 PROC_LOCK(p); 135 if (p->p_flag & P_THREADED || p->p_numthreads > 1) { 136 /* 137 * First check if some other thread got here before us.. 138 * if so, act apropriatly, (exit or suspend); 139 */ 140 DROP_GIANT(); 141 thread_suspend_check(0); 142 PICKUP_GIANT(); 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_THREADED; 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 if (timevalisset(&p->p_realtimer.it_value)) 224 callout_stop(&p->p_itcallout); 225 PROC_UNLOCK(p); 226 227 /* 228 * Reset any sigio structures pointing to us as a result of 229 * F_SETOWN with our pid. 230 */ 231 funsetownlst(&p->p_sigiolst); 232 233 /* 234 * Close open files and release open-file table. 235 * This may block! 236 */ 237 fdfree(td); 238 239 /* 240 * Remove ourself from our leader's peer list and wake our leader. 241 */ 242 mtx_lock(&ppeers_lock); 243 if (p->p_leader->p_peers) { 244 q = p->p_leader; 245 while (q->p_peers != p) 246 q = q->p_peers; 247 q->p_peers = p->p_peers; 248 wakeup(p->p_leader); 249 } 250 mtx_unlock(&ppeers_lock); 251 252 /* The next two chunks should probably be moved to vmspace_exit. */ 253 vm = p->p_vmspace; 254 /* 255 * Release user portion of address space. 256 * This releases references to vnodes, 257 * which could cause I/O if the file has been unlinked. 258 * Need to do this early enough that we can still sleep. 259 * Can't free the entire vmspace as the kernel stack 260 * may be mapped within that space also. 261 * 262 * Processes sharing the same vmspace may exit in one order, and 263 * get cleaned up by vmspace_exit() in a different order. The 264 * last exiting process to reach this point releases as much of 265 * the environment as it can, and the last process cleaned up 266 * by vmspace_exit() (which decrements exitingcnt) cleans up the 267 * remainder. 268 */ 269 ++vm->vm_exitingcnt; 270 if (--vm->vm_refcnt == 0) { 271 shmexit(vm); 272 vm_page_lock_queues(); 273 pmap_remove_pages(vmspace_pmap(vm), vm_map_min(&vm->vm_map), 274 vm_map_max(&vm->vm_map)); 275 vm_page_unlock_queues(); 276 (void) vm_map_remove(&vm->vm_map, vm_map_min(&vm->vm_map), 277 vm_map_max(&vm->vm_map)); 278 } 279 280 sx_xlock(&proctree_lock); 281 if (SESS_LEADER(p)) { 282 struct session *sp; 283 284 sp = p->p_session; 285 if (sp->s_ttyvp) { 286 /* 287 * Controlling process. 288 * Signal foreground pgrp, 289 * drain controlling terminal 290 * and revoke access to controlling terminal. 291 */ 292 if (sp->s_ttyp && (sp->s_ttyp->t_session == sp)) { 293 tp = sp->s_ttyp; 294 if (sp->s_ttyp->t_pgrp) { 295 PGRP_LOCK(sp->s_ttyp->t_pgrp); 296 pgsignal(sp->s_ttyp->t_pgrp, SIGHUP, 1); 297 PGRP_UNLOCK(sp->s_ttyp->t_pgrp); 298 } 299 /* XXX tp should be locked. */ 300 sx_xunlock(&proctree_lock); 301 (void) ttywait(tp); 302 sx_xlock(&proctree_lock); 303 /* 304 * The tty could have been revoked 305 * if we blocked. 306 */ 307 if (sp->s_ttyvp) { 308 ttyvp = sp->s_ttyvp; 309 SESS_LOCK(p->p_session); 310 sp->s_ttyvp = NULL; 311 SESS_UNLOCK(p->p_session); 312 sx_xunlock(&proctree_lock); 313 VOP_REVOKE(ttyvp, REVOKEALL); 314 vrele(ttyvp); 315 sx_xlock(&proctree_lock); 316 } 317 } 318 if (sp->s_ttyvp) { 319 ttyvp = sp->s_ttyvp; 320 SESS_LOCK(p->p_session); 321 sp->s_ttyvp = NULL; 322 SESS_UNLOCK(p->p_session); 323 vrele(ttyvp); 324 } 325 /* 326 * s_ttyp is not zero'd; we use this to indicate 327 * that the session once had a controlling terminal. 328 * (for logging and informational purposes) 329 */ 330 } 331 SESS_LOCK(p->p_session); 332 sp->s_leader = NULL; 333 SESS_UNLOCK(p->p_session); 334 } 335 fixjobc(p, p->p_pgrp, 0); 336 sx_xunlock(&proctree_lock); 337 (void)acct_process(td); 338 #ifdef KTRACE 339 /* 340 * release trace file 341 */ 342 PROC_LOCK(p); 343 mtx_lock(&ktrace_mtx); 344 p->p_traceflag = 0; /* don't trace the vrele() */ 345 tracevp = p->p_tracevp; 346 p->p_tracevp = NULL; 347 tracecred = p->p_tracecred; 348 p->p_tracecred = NULL; 349 mtx_unlock(&ktrace_mtx); 350 PROC_UNLOCK(p); 351 if (tracevp != NULL) 352 vrele(tracevp); 353 if (tracecred != NULL) 354 crfree(tracecred); 355 #endif 356 /* 357 * Release reference to text vnode 358 */ 359 if ((vtmp = p->p_textvp) != NULL) { 360 p->p_textvp = NULL; 361 vrele(vtmp); 362 } 363 364 /* 365 * Release our limits structure. 366 */ 367 mtx_assert(&Giant, MA_OWNED); 368 if (--p->p_limit->p_refcnt == 0) { 369 FREE(p->p_limit, M_SUBPROC); 370 p->p_limit = NULL; 371 } 372 373 /* 374 * Release this thread's reference to the ucred. The actual proc 375 * reference will stay around until the proc is harvested by 376 * wait(). At this point the ucred is immutable (no other threads 377 * from this proc are around that can change it) so we leave the 378 * per-thread ucred pointer intact in case it is needed although 379 * in theory nothing should be using it at this point. 380 */ 381 crfree(td->td_ucred); 382 383 /* 384 * Remove proc from allproc queue and pidhash chain. 385 * Place onto zombproc. Unlink from parent's child list. 386 */ 387 sx_xlock(&allproc_lock); 388 LIST_REMOVE(p, p_list); 389 LIST_INSERT_HEAD(&zombproc, p, p_list); 390 LIST_REMOVE(p, p_hash); 391 sx_xunlock(&allproc_lock); 392 393 sx_xlock(&proctree_lock); 394 q = LIST_FIRST(&p->p_children); 395 if (q != NULL) /* only need this if any child is S_ZOMB */ 396 wakeup(initproc); 397 for (; q != NULL; q = nq) { 398 nq = LIST_NEXT(q, p_sibling); 399 PROC_LOCK(q); 400 proc_reparent(q, initproc); 401 q->p_sigparent = SIGCHLD; 402 /* 403 * Traced processes are killed 404 * since their existence means someone is screwing up. 405 */ 406 if (q->p_flag & P_TRACED) { 407 q->p_flag &= ~P_TRACED; 408 psignal(q, SIGKILL); 409 } 410 PROC_UNLOCK(q); 411 } 412 413 /* 414 * Save exit status and final rusage info, adding in child rusage 415 * info and self times. 416 */ 417 PROC_LOCK(p); 418 p->p_xstat = rv; 419 *p->p_ru = p->p_stats->p_ru; 420 mtx_lock_spin(&sched_lock); 421 calcru(p, &p->p_ru->ru_utime, &p->p_ru->ru_stime, NULL); 422 mtx_unlock_spin(&sched_lock); 423 ruadd(p->p_ru, &p->p_stats->p_cru); 424 425 /* 426 * Notify interested parties of our demise. 427 */ 428 KNOTE(&p->p_klist, NOTE_EXIT); 429 430 /* 431 * Notify parent that we're gone. If parent has the PS_NOCLDWAIT 432 * flag set, or if the handler is set to SIG_IGN, notify process 433 * 1 instead (and hope it will handle this situation). 434 */ 435 PROC_LOCK(p->p_pptr); 436 if (p->p_pptr->p_procsig->ps_flag & (PS_NOCLDWAIT | PS_CLDSIGIGN)) { 437 struct proc *pp; 438 439 pp = p->p_pptr; 440 PROC_UNLOCK(pp); 441 proc_reparent(p, initproc); 442 PROC_LOCK(p->p_pptr); 443 /* 444 * If this was the last child of our parent, notify 445 * parent, so in case he was wait(2)ing, he will 446 * continue. 447 */ 448 if (LIST_EMPTY(&pp->p_children)) 449 wakeup(pp); 450 } 451 452 if (p->p_sigparent && p->p_pptr != initproc) 453 psignal(p->p_pptr, p->p_sigparent); 454 else 455 psignal(p->p_pptr, SIGCHLD); 456 PROC_UNLOCK(p->p_pptr); 457 458 /* 459 * If this is a kthread, then wakeup anyone waiting for it to exit. 460 */ 461 if (p->p_flag & P_KTHREAD) 462 wakeup(p); 463 PROC_UNLOCK(p); 464 465 /* 466 * Finally, call machine-dependent code to release the remaining 467 * resources including address space. 468 * The address space is released by "vmspace_exitfree(p)" in 469 * vm_waitproc(). 470 */ 471 cpu_exit(td); 472 473 PROC_LOCK(p); 474 PROC_LOCK(p->p_pptr); 475 sx_xunlock(&proctree_lock); 476 mtx_lock_spin(&sched_lock); 477 478 while (mtx_owned(&Giant)) 479 mtx_unlock(&Giant); 480 481 /* 482 * We have to wait until after releasing all locks before 483 * changing p_state. If we block on a mutex then we will be 484 * back at SRUN when we resume and our parent will never 485 * harvest us. 486 */ 487 p->p_state = PRS_ZOMBIE; 488 489 wakeup(p->p_pptr); 490 PROC_UNLOCK(p->p_pptr); 491 cnt.v_swtch++; 492 binuptime(PCPU_PTR(switchtime)); 493 PCPU_SET(switchticks, ticks); 494 495 cpu_sched_exit(td); /* XXXKSE check if this should be in thread_exit */ 496 /* 497 * Make sure the scheduler takes this thread out of its tables etc. 498 * This will also release this thread's reference to the ucred. 499 * Other thread parts to release include pcb bits and such. 500 */ 501 thread_exit(); 502 } 503 504 #ifdef COMPAT_43 505 /* 506 * MPSAFE. The dirty work is handled by wait1(). 507 */ 508 int 509 owait(struct thread *td, struct owait_args *uap __unused) 510 { 511 struct wait_args w; 512 513 w.options = 0; 514 w.rusage = NULL; 515 w.pid = WAIT_ANY; 516 w.status = NULL; 517 return (wait1(td, &w, 1)); 518 } 519 #endif /* COMPAT_43 */ 520 521 /* 522 * MPSAFE. The dirty work is handled by wait1(). 523 */ 524 int 525 wait4(struct thread *td, struct wait_args *uap) 526 { 527 528 return (wait1(td, uap, 0)); 529 } 530 531 /* 532 * MPSAFE 533 */ 534 static int 535 wait1(struct thread *td, struct wait_args *uap, int compat) 536 { 537 struct rusage ru; 538 int nfound; 539 struct proc *p, *q, *t; 540 int status, error; 541 542 q = td->td_proc; 543 if (uap->pid == 0) { 544 PROC_LOCK(q); 545 uap->pid = -q->p_pgid; 546 PROC_UNLOCK(q); 547 } 548 if (uap->options &~ (WUNTRACED|WNOHANG|WCONTINUED|WLINUXCLONE)) 549 return (EINVAL); 550 mtx_lock(&Giant); 551 loop: 552 nfound = 0; 553 sx_xlock(&proctree_lock); 554 LIST_FOREACH(p, &q->p_children, p_sibling) { 555 PROC_LOCK(p); 556 if (uap->pid != WAIT_ANY && 557 p->p_pid != uap->pid && p->p_pgid != -uap->pid) { 558 PROC_UNLOCK(p); 559 continue; 560 } 561 562 /* 563 * This special case handles a kthread spawned by linux_clone 564 * (see linux_misc.c). The linux_wait4 and linux_waitpid 565 * functions need to be able to distinguish between waiting 566 * on a process and waiting on a thread. It is a thread if 567 * p_sigparent is not SIGCHLD, and the WLINUXCLONE option 568 * signifies we want to wait for threads and not processes. 569 */ 570 if ((p->p_sigparent != SIGCHLD) ^ 571 ((uap->options & WLINUXCLONE) != 0)) { 572 PROC_UNLOCK(p); 573 continue; 574 } 575 576 nfound++; 577 if (p->p_state == PRS_ZOMBIE) { 578 /* 579 * Allow the scheduler to adjust the priority of the 580 * parent when a kseg is exiting. 581 */ 582 if (curthread->td_proc->p_pid != 1) { 583 mtx_lock_spin(&sched_lock); 584 sched_exit(curthread->td_ksegrp, 585 FIRST_KSEGRP_IN_PROC(p)); 586 mtx_unlock_spin(&sched_lock); 587 } 588 589 td->td_retval[0] = p->p_pid; 590 #ifdef COMPAT_43 591 if (compat) 592 td->td_retval[1] = p->p_xstat; 593 else 594 #endif 595 if (uap->status) { 596 status = p->p_xstat; /* convert to int */ 597 PROC_UNLOCK(p); 598 if ((error = copyout(&status, 599 uap->status, sizeof(status)))) { 600 sx_xunlock(&proctree_lock); 601 mtx_unlock(&Giant); 602 return (error); 603 } 604 PROC_LOCK(p); 605 } 606 if (uap->rusage) { 607 bcopy(p->p_ru, &ru, sizeof(ru)); 608 PROC_UNLOCK(p); 609 if ((error = copyout(&ru, 610 uap->rusage, sizeof (struct rusage)))) { 611 sx_xunlock(&proctree_lock); 612 mtx_unlock(&Giant); 613 return (error); 614 } 615 } else 616 PROC_UNLOCK(p); 617 /* 618 * If we got the child via a ptrace 'attach', 619 * we need to give it back to the old parent. 620 */ 621 if (p->p_oppid && (t = pfind(p->p_oppid)) != NULL) { 622 PROC_LOCK(p); 623 p->p_oppid = 0; 624 proc_reparent(p, t); 625 PROC_UNLOCK(p); 626 psignal(t, SIGCHLD); 627 wakeup(t); 628 PROC_UNLOCK(t); 629 sx_xunlock(&proctree_lock); 630 mtx_unlock(&Giant); 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, p->p_ru); 655 PROC_UNLOCK(q); 656 FREE(p->p_ru, M_ZOMBIE); 657 p->p_ru = NULL; 658 659 /* 660 * Decrement the count of procs running with this uid. 661 */ 662 (void)chgproccnt(p->p_ucred->cr_ruidinfo, -1, 0); 663 664 /* 665 * Free up credentials. 666 */ 667 crfree(p->p_ucred); 668 p->p_ucred = NULL; /* XXX: why? */ 669 670 /* 671 * Remove unused arguments 672 */ 673 pargs_drop(p->p_args); 674 p->p_args = NULL; 675 676 if (--p->p_procsig->ps_refcnt == 0) { 677 if (p->p_sigacts != &p->p_uarea->u_sigacts) 678 FREE(p->p_sigacts, M_SUBPROC); 679 FREE(p->p_procsig, M_SUBPROC); 680 p->p_procsig = NULL; 681 } 682 683 /* 684 * do any thread-system specific cleanups 685 */ 686 thread_wait(p); 687 688 /* 689 * Give vm and machine-dependent layer a chance 690 * to free anything that cpu_exit couldn't 691 * release while still running in process context. 692 */ 693 vm_waitproc(p); 694 mtx_destroy(&p->p_mtx); 695 #ifdef MAC 696 mac_destroy_proc(p); 697 #endif 698 KASSERT(FIRST_THREAD_IN_PROC(p), 699 ("wait1: no residual thread!")); 700 uma_zfree(proc_zone, p); 701 sx_xlock(&allproc_lock); 702 nprocs--; 703 sx_xunlock(&allproc_lock); 704 mtx_unlock(&Giant); 705 return (0); 706 } 707 if (P_SHOULDSTOP(p) && (p->p_suspcount == p->p_numthreads) && 708 ((p->p_flag & P_WAITED) == 0) && 709 (p->p_flag & P_TRACED || uap->options & WUNTRACED)) { 710 p->p_flag |= P_WAITED; 711 sx_xunlock(&proctree_lock); 712 td->td_retval[0] = p->p_pid; 713 #ifdef COMPAT_43 714 if (compat) { 715 td->td_retval[1] = W_STOPCODE(p->p_xstat); 716 PROC_UNLOCK(p); 717 error = 0; 718 } else 719 #endif 720 if (uap->status) { 721 status = W_STOPCODE(p->p_xstat); 722 PROC_UNLOCK(p); 723 error = copyout(&status, 724 uap->status, sizeof(status)); 725 } else { 726 PROC_UNLOCK(p); 727 error = 0; 728 } 729 mtx_unlock(&Giant); 730 return (error); 731 } 732 if (uap->options & WCONTINUED && (p->p_flag & P_CONTINUED)) { 733 sx_xunlock(&proctree_lock); 734 td->td_retval[0] = p->p_pid; 735 p->p_flag &= ~P_CONTINUED; 736 PROC_UNLOCK(p); 737 738 if (uap->status) { 739 status = SIGCONT; 740 error = copyout(&status, 741 uap->status, sizeof(status)); 742 } else 743 error = 0; 744 745 mtx_unlock(&Giant); 746 return (error); 747 } 748 PROC_UNLOCK(p); 749 } 750 if (nfound == 0) { 751 sx_xunlock(&proctree_lock); 752 mtx_unlock(&Giant); 753 return (ECHILD); 754 } 755 if (uap->options & WNOHANG) { 756 sx_xunlock(&proctree_lock); 757 td->td_retval[0] = 0; 758 mtx_unlock(&Giant); 759 return (0); 760 } 761 PROC_LOCK(q); 762 sx_xunlock(&proctree_lock); 763 error = msleep(q, &q->p_mtx, PWAIT | PCATCH, "wait", 0); 764 PROC_UNLOCK(q); 765 if (error) { 766 mtx_unlock(&Giant); 767 return (error); 768 } 769 goto loop; 770 } 771 772 /* 773 * Make process 'parent' the new parent of process 'child'. 774 * Must be called with an exclusive hold of proctree lock. 775 */ 776 void 777 proc_reparent(struct proc *child, struct proc *parent) 778 { 779 780 sx_assert(&proctree_lock, SX_XLOCKED); 781 PROC_LOCK_ASSERT(child, MA_OWNED); 782 if (child->p_pptr == parent) 783 return; 784 785 LIST_REMOVE(child, p_sibling); 786 LIST_INSERT_HEAD(&parent->p_children, child, p_sibling); 787 child->p_pptr = parent; 788 } 789