1 /* $NetBSD: kern_exit.c,v 1.107 2003/01/18 10:06:26 thorpej Exp $ */ 2 3 /*- 4 * Copyright (c) 1998, 1999 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the NetBSD 22 * Foundation, Inc. and its contributors. 23 * 4. Neither the name of The NetBSD Foundation nor the names of its 24 * contributors may be used to endorse or promote products derived 25 * from this software without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 37 * POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40 /* 41 * Copyright (c) 1982, 1986, 1989, 1991, 1993 42 * The Regents of the University of California. All rights reserved. 43 * (c) UNIX System Laboratories, Inc. 44 * All or some portions of this file are derived from material licensed 45 * to the University of California by American Telephone and Telegraph 46 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 47 * the permission of UNIX System Laboratories, Inc. 48 * 49 * Redistribution and use in source and binary forms, with or without 50 * modification, are permitted provided that the following conditions 51 * are met: 52 * 1. Redistributions of source code must retain the above copyright 53 * notice, this list of conditions and the following disclaimer. 54 * 2. Redistributions in binary form must reproduce the above copyright 55 * notice, this list of conditions and the following disclaimer in the 56 * documentation and/or other materials provided with the distribution. 57 * 3. All advertising materials mentioning features or use of this software 58 * must display the following acknowledgement: 59 * This product includes software developed by the University of 60 * California, Berkeley and its contributors. 61 * 4. Neither the name of the University nor the names of its contributors 62 * may be used to endorse or promote products derived from this software 63 * without specific prior written permission. 64 * 65 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 66 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 67 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 68 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 69 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 70 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 71 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 72 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 73 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 74 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 75 * SUCH DAMAGE. 76 * 77 * @(#)kern_exit.c 8.10 (Berkeley) 2/23/95 78 */ 79 80 #include <sys/cdefs.h> 81 __KERNEL_RCSID(0, "$NetBSD: kern_exit.c,v 1.107 2003/01/18 10:06:26 thorpej Exp $"); 82 83 #include "opt_ktrace.h" 84 #include "opt_perfctrs.h" 85 #include "opt_systrace.h" 86 #include "opt_sysv.h" 87 88 #include <sys/param.h> 89 #include <sys/systm.h> 90 #include <sys/ioctl.h> 91 #include <sys/proc.h> 92 #include <sys/tty.h> 93 #include <sys/time.h> 94 #include <sys/resource.h> 95 #include <sys/kernel.h> 96 #include <sys/ktrace.h> 97 #include <sys/proc.h> 98 #include <sys/buf.h> 99 #include <sys/wait.h> 100 #include <sys/file.h> 101 #include <sys/vnode.h> 102 #include <sys/syslog.h> 103 #include <sys/malloc.h> 104 #include <sys/pool.h> 105 #include <sys/resourcevar.h> 106 #if defined(PERFCTRS) 107 #include <sys/pmc.h> 108 #endif 109 #include <sys/ptrace.h> 110 #include <sys/acct.h> 111 #include <sys/filedesc.h> 112 #include <sys/ras.h> 113 #include <sys/signalvar.h> 114 #include <sys/sched.h> 115 #include <sys/sa.h> 116 #include <sys/savar.h> 117 #include <sys/mount.h> 118 #include <sys/syscallargs.h> 119 #include <sys/systrace.h> 120 121 #include <machine/cpu.h> 122 123 #include <uvm/uvm_extern.h> 124 125 #define DEBUG_EXIT 126 127 #ifdef DEBUG_EXIT 128 int debug_exit = 0; 129 #define DPRINTF(x) if (debug_exit) printf x 130 #else 131 #define DPRINTF(x) 132 #endif 133 134 static void lwp_exit_hook(struct lwp *, void *); 135 136 /* 137 * exit -- 138 * Death of process. 139 */ 140 int 141 sys_exit(struct lwp *l, void *v, register_t *retval) 142 { 143 struct sys_exit_args /* { 144 syscallarg(int) rval; 145 } */ *uap = v; 146 147 /* Don't call exit1() multiple times in the same process.*/ 148 if (l->l_proc->p_flag & P_WEXIT) 149 lwp_exit(l); 150 151 exit1(l, W_EXITCODE(SCARG(uap, rval), 0)); 152 /* NOTREACHED */ 153 return (0); 154 } 155 156 /* 157 * Exit: deallocate address space and other resources, change proc state 158 * to zombie, and unlink proc from allproc and parent's lists. Save exit 159 * status and rusage for wait(). Check for child processes and orphan them. 160 */ 161 void 162 exit1(struct lwp *l, int rv) 163 { 164 struct proc *p, *q, *nq; 165 int s; 166 167 p = l->l_proc; 168 169 if (__predict_false(p == initproc)) 170 panic("init died (signal %d, exit %d)", 171 WTERMSIG(rv), WEXITSTATUS(rv)); 172 173 DPRINTF(("exit1: %d.%d exiting.\n", p->p_pid, l->l_lid)); 174 /* 175 * Disable scheduler activation upcalls. 176 * We're trying to get out of here. 177 */ 178 if (l->l_flag & L_SA) { 179 l->l_flag &= ~L_SA; 180 p->p_flag &= ~P_SA; 181 } 182 183 #ifdef PGINPROF 184 vmsizmon(); 185 #endif 186 if (p->p_flag & P_PROFIL) 187 stopprofclock(p); 188 p->p_ru = pool_get(&rusage_pool, PR_WAITOK); 189 /* 190 * If parent is waiting for us to exit or exec, P_PPWAIT is set; we 191 * wake up the parent early to avoid deadlock. 192 */ 193 p->p_flag |= P_WEXIT; 194 if (p->p_flag & P_PPWAIT) { 195 p->p_flag &= ~P_PPWAIT; 196 wakeup((caddr_t)p->p_pptr); 197 } 198 sigfillset(&p->p_sigctx.ps_sigignore); 199 sigemptyset(&p->p_sigctx.ps_siglist); 200 p->p_sigctx.ps_sigcheck = 0; 201 timers_free(p, TIMERS_ALL); 202 203 if (p->p_nlwps > 1) 204 exit_lwps(l); 205 206 #if defined(__HAVE_RAS) 207 ras_purgeall(p); 208 #endif 209 210 /* 211 * Close open files and release open-file table. 212 * This may block! 213 */ 214 fdfree(p); 215 cwdfree(p); 216 217 doexithooks(p); 218 219 if (SESS_LEADER(p)) { 220 struct session *sp = p->p_session; 221 222 if (sp->s_ttyvp) { 223 /* 224 * Controlling process. 225 * Signal foreground pgrp, 226 * drain controlling terminal 227 * and revoke access to controlling terminal. 228 */ 229 if (sp->s_ttyp->t_session == sp) { 230 if (sp->s_ttyp->t_pgrp) 231 pgsignal(sp->s_ttyp->t_pgrp, SIGHUP, 1); 232 (void) ttywait(sp->s_ttyp); 233 /* 234 * The tty could have been revoked 235 * if we blocked. 236 */ 237 if (sp->s_ttyvp) 238 VOP_REVOKE(sp->s_ttyvp, REVOKEALL); 239 } 240 if (sp->s_ttyvp) 241 vrele(sp->s_ttyvp); 242 sp->s_ttyvp = NULL; 243 /* 244 * s_ttyp is not zero'd; we use this to indicate 245 * that the session once had a controlling terminal. 246 * (for logging and informational purposes) 247 */ 248 } 249 sp->s_leader = NULL; 250 } 251 fixjobc(p, p->p_pgrp, 0); 252 (void)acct_process(p); 253 #ifdef KTRACE 254 /* 255 * release trace file 256 */ 257 ktrderef(p); 258 #endif 259 #ifdef SYSTRACE 260 systrace_sys_exit(p); 261 #endif 262 /* 263 * If emulation has process exit hook, call it now. 264 */ 265 if (p->p_emul->e_proc_exit) 266 (*p->p_emul->e_proc_exit)(p); 267 268 /* 269 * NOTE: WE ARE NO LONGER ALLOWED TO SLEEP! 270 */ 271 p->p_stat = SDEAD; 272 p->p_nrlwps--; 273 l->l_stat = SDEAD; 274 275 /* 276 * Remove proc from pidhash chain so looking it up won't 277 * work. Move it from allproc to zombproc, but do not yet 278 * wake up the reaper. We will put the proc on the 279 * deadproc list later (using the p_hash member), and 280 * wake up the reaper when we do. 281 */ 282 s = proclist_lock_write(); 283 LIST_REMOVE(p, p_hash); 284 LIST_REMOVE(p, p_list); 285 LIST_INSERT_HEAD(&zombproc, p, p_list); 286 LIST_REMOVE(l, l_list); 287 l->l_flag |= L_DETACHED; 288 proclist_unlock_write(s); 289 290 /* 291 * Give orphaned children to init(8). 292 */ 293 q = LIST_FIRST(&p->p_children); 294 if (q) /* only need this if any child is S_ZOMB */ 295 wakeup((caddr_t)initproc); 296 for (; q != 0; q = nq) { 297 nq = LIST_NEXT(q, p_sibling); 298 299 /* 300 * Traced processes are killed since their existence 301 * means someone is screwing up. Since we reset the 302 * trace flags, the logic in sys_wait4() would not be 303 * triggered to reparent the process to its 304 * original parent, so we must do this here. 305 */ 306 if (q->p_flag & P_TRACED) { 307 if (q->p_opptr != q->p_pptr) { 308 struct proc *t = q->p_opptr; 309 proc_reparent(q, t ? t : initproc); 310 q->p_opptr = NULL; 311 } else 312 proc_reparent(q, initproc); 313 q->p_flag &= ~(P_TRACED|P_WAITED|P_FSTRACE); 314 psignal(q, SIGKILL); 315 } else { 316 proc_reparent(q, initproc); 317 } 318 } 319 320 /* 321 * Reset p_opptr pointer of all former children which got 322 * traced by another process and were reparented. We reset 323 * it to NULL here; the trace detach code then reparents 324 * the child to initproc. We only check allproc list, since 325 * eventual former children on zombproc list won't reference 326 * p_opptr anymore. 327 */ 328 if (p->p_flag & P_CHTRACED) { 329 struct proc *t; 330 331 proclist_lock_read(); 332 333 LIST_FOREACH(t, &allproc, p_list) { 334 if (t->p_opptr == p) 335 t->p_opptr = NULL; 336 } 337 338 proclist_unlock_read(); 339 } 340 341 /* 342 * Save exit status and final rusage info, adding in child rusage 343 * info and self times. 344 */ 345 p->p_xstat = rv; 346 *p->p_ru = p->p_stats->p_ru; 347 calcru(p, &p->p_ru->ru_utime, &p->p_ru->ru_stime, NULL); 348 ruadd(p->p_ru, &p->p_stats->p_cru); 349 350 /* 351 * Notify interested parties of our demise. 352 */ 353 KNOTE(&p->p_klist, NOTE_EXIT); 354 355 #if PERFCTRS 356 /* 357 * Save final PMC information in parent process & clean up. 358 */ 359 if (PMC_ENABLED(p)) { 360 pmc_save_context(p); 361 pmc_accumulate(p->p_pptr, p); 362 pmc_process_exit(p); 363 } 364 #endif 365 366 /* 367 * Notify parent that we're gone. If parent has the P_NOCLDWAIT 368 * flag set, notify init instead (and hope it will handle 369 * this situation). 370 */ 371 if (p->p_pptr->p_flag & P_NOCLDWAIT) { 372 struct proc *pp = p->p_pptr; 373 proc_reparent(p, initproc); 374 /* 375 * If this was the last child of our parent, notify 376 * parent, so in case he was wait(2)ing, he will 377 * continue. 378 */ 379 if (LIST_FIRST(&pp->p_children) == NULL) 380 wakeup((caddr_t)pp); 381 } 382 383 /* 384 * Release the process's signal state. 385 */ 386 sigactsfree(p); 387 388 /* 389 * Clear curlwp after we've done all operations 390 * that could block, and before tearing down the rest 391 * of the process state that might be used from clock, etc. 392 * Also, can't clear curlwp while we're still runnable, 393 * as we're not on a run queue (we are current, just not 394 * a proper proc any longer!). 395 * 396 * Other substructures are freed from wait(). 397 */ 398 curlwp = NULL; 399 limfree(p->p_limit); 400 pstatsfree(p->p_stats); 401 p->p_limit = NULL; 402 403 /* This process no longer needs to hold the kernel lock. */ 404 KERNEL_PROC_UNLOCK(l); 405 406 /* 407 * Finally, call machine-dependent code to switch to a new 408 * context (possibly the idle context). Once we are no longer 409 * using the dead process's vmspace and stack, exit2() will be 410 * called to schedule those resources to be released by the 411 * reaper thread. 412 * 413 * Note that cpu_exit() will end with a call equivalent to 414 * cpu_switch(), finishing our execution (pun intended). 415 */ 416 417 cpu_exit(l, 1); 418 } 419 420 void 421 exit_lwps(struct lwp *l) 422 { 423 struct proc *p; 424 struct lwp *l2; 425 int s, error; 426 lwpid_t waited; 427 428 p = l->l_proc; 429 430 /* XXX SMP 431 * This would be the right place to IPI any LWPs running on 432 * other processors so that they can notice the userret exit hook. 433 */ 434 p->p_userret = lwp_exit_hook; 435 p->p_userret_arg = NULL; 436 437 /* 438 * Make SA-cached LWPs normal process runnable LWPs so that 439 * they'll also self-destruct. 440 */ 441 if (p->p_sa && p->p_sa->sa_ncached > 0) { 442 DPRINTF(("exit_lwps: Making cached LWPs of %d runnable: ", 443 p->p_pid)); 444 SCHED_LOCK(s); 445 while ((l2 = sa_getcachelwp(p)) != 0) { 446 l2->l_priority = l2->l_usrpri; 447 setrunnable(l2); 448 DPRINTF(("%d ", l2->l_lid)); 449 } 450 DPRINTF(("\n")); 451 SCHED_UNLOCK(s); 452 } 453 454 /* 455 * Interrupt LWPs in interruptable sleep, unsuspend suspended 456 * LWPs, make detached LWPs undeached (so we can wait for 457 * them) and then wait for everyone else to finish. 458 */ 459 LIST_FOREACH(l2, &p->p_lwps, l_sibling) { 460 l2->l_flag &= ~(L_DETACHED|L_SA); 461 if ((l2->l_stat == LSSLEEP && (l2->l_flag & L_SINTR)) || 462 l2->l_stat == LSSUSPENDED) { 463 SCHED_LOCK(s); 464 setrunnable(l2); 465 SCHED_UNLOCK(s); 466 DPRINTF(("exit_lwps: Made %d.%d runnable\n", 467 p->p_pid, l2->l_lid)); 468 } 469 } 470 471 472 while (p->p_nlwps > 1) { 473 DPRINTF(("exit_lwps: waiting for %d LWPs (%d runnable, %d zombies)\n", 474 p->p_nlwps, p->p_nrlwps, p->p_nzlwps)); 475 error = lwp_wait1(l, 0, &waited, LWPWAIT_EXITCONTROL); 476 if (error) 477 panic("exit_lwps: lwp_wait1 failed with error %d\n", 478 error); 479 DPRINTF(("exit_lwps: Got LWP %d from lwp_wait1()\n", waited)); 480 } 481 482 p->p_userret = NULL; 483 } 484 485 /* Wrapper function for use in p_userret */ 486 static void 487 lwp_exit_hook(struct lwp *l, void *arg) 488 { 489 KERNEL_PROC_LOCK(l); 490 lwp_exit(l); 491 } 492 493 /* 494 * We are called from cpu_exit() once it is safe to schedule the 495 * dead process's resources to be freed (i.e., once we've switched to 496 * the idle PCB for the current CPU). 497 * 498 * NOTE: One must be careful with locking in this routine. It's 499 * called from a critical section in machine-dependent code, so 500 * we should refrain from changing any interrupt state. 501 * 502 * We lock the deadproc list (a spin lock), place the proc on that 503 * list (using the p_hash member), and wake up the reaper. 504 */ 505 void 506 exit2(struct lwp *l) 507 { 508 struct proc *p = l->l_proc; 509 510 simple_lock(&deadproc_slock); 511 LIST_INSERT_HEAD(&deadproc, p, p_hash); 512 simple_unlock(&deadproc_slock); 513 514 /* lwp_exit2() will wake up deadproc for us. */ 515 lwp_exit2(l); 516 } 517 518 /* 519 * Process reaper. This is run by a kernel thread to free the resources 520 * of a dead process. Once the resources are free, the process becomes 521 * a zombie, and the parent is allowed to read the undead's status. 522 */ 523 void 524 reaper(void *arg) 525 { 526 struct proc *p; 527 struct lwp *l; 528 529 KERNEL_PROC_UNLOCK(curlwp); 530 531 for (;;) { 532 simple_lock(&deadproc_slock); 533 p = LIST_FIRST(&deadproc); 534 l = LIST_FIRST(&deadlwp); 535 if (p == NULL && l == NULL) { 536 /* No work for us; go to sleep until someone exits. */ 537 (void) ltsleep(&deadproc, PVM|PNORELOCK, 538 "reaper", 0, &deadproc_slock); 539 continue; 540 } 541 542 if (l != NULL ) { 543 p = l->l_proc; 544 545 /* Remove us from the deadlwp list. */ 546 LIST_REMOVE(l, l_list); 547 simple_unlock(&deadproc_slock); 548 KERNEL_PROC_LOCK(curlwp); 549 550 /* 551 * Give machine-dependent code a chance to free any 552 * resources it couldn't free while still running on 553 * that process's context. This must be done before 554 * uvm_lwp_exit(), in case these resources are in the 555 * PCB. 556 */ 557 cpu_wait(l); 558 559 /* 560 * Free the VM resources we're still holding on to. 561 */ 562 uvm_lwp_exit(l); 563 564 l->l_stat = LSZOMB; 565 if (l->l_flag & L_DETACHED) { 566 /* Nobody waits for detached LWPs. */ 567 LIST_REMOVE(l, l_sibling); 568 p->p_nlwps--; 569 pool_put(&lwp_pool, l); 570 } else { 571 p->p_nzlwps++; 572 wakeup((caddr_t)&p->p_nlwps); 573 } 574 /* XXXNJW where should this be with respect to 575 * the wakeup() above? */ 576 KERNEL_PROC_UNLOCK(curlwp); 577 } else { 578 /* Remove us from the deadproc list. */ 579 LIST_REMOVE(p, p_hash); 580 simple_unlock(&deadproc_slock); 581 KERNEL_PROC_LOCK(curlwp); 582 583 /* 584 * Free the VM resources we're still holding on to. 585 * We must do this from a valid thread because doing 586 * so may block. 587 */ 588 uvm_proc_exit(p); 589 590 /* Process is now a true zombie. */ 591 p->p_stat = SZOMB; 592 593 /* Wake up the parent so it can get exit status. */ 594 if ((p->p_flag & P_FSTRACE) == 0 && p->p_exitsig != 0) 595 psignal(p->p_pptr, P_EXITSIG(p)); 596 KERNEL_PROC_UNLOCK(curlwp); 597 wakeup((caddr_t)p->p_pptr); 598 } 599 } 600 } 601 602 int 603 sys_wait4(struct lwp *l, void *v, register_t *retval) 604 { 605 struct sys_wait4_args /* { 606 syscallarg(int) pid; 607 syscallarg(int *) status; 608 syscallarg(int) options; 609 syscallarg(struct rusage *) rusage; 610 } */ *uap = v; 611 struct proc *p, *q, *t; 612 int nfound, status, error, s; 613 614 q = l->l_proc; 615 616 if (SCARG(uap, pid) == 0) 617 SCARG(uap, pid) = -q->p_pgid; 618 if (SCARG(uap, options) &~ (WUNTRACED|WNOHANG|WALTSIG)) 619 return (EINVAL); 620 621 loop: 622 nfound = 0; 623 LIST_FOREACH(p, &q->p_children, p_sibling) { 624 if (SCARG(uap, pid) != WAIT_ANY && 625 p->p_pid != SCARG(uap, pid) && 626 p->p_pgid != -SCARG(uap, pid)) 627 continue; 628 /* 629 * Wait for processes with p_exitsig != SIGCHLD processes only 630 * if WALTSIG is set; wait for processes with p_exitsig == 631 * SIGCHLD only if WALTSIG is clear. 632 */ 633 if (((SCARG(uap, options) & WALLSIG) == 0) && 634 ((SCARG(uap, options) & WALTSIG) ? 635 (p->p_exitsig == SIGCHLD) : (P_EXITSIG(p) != SIGCHLD))) 636 continue; 637 638 nfound++; 639 if (p->p_stat == SZOMB) { 640 retval[0] = p->p_pid; 641 642 if (SCARG(uap, status)) { 643 status = p->p_xstat; /* convert to int */ 644 error = copyout((caddr_t)&status, 645 (caddr_t)SCARG(uap, status), 646 sizeof(status)); 647 if (error) 648 return (error); 649 } 650 if (SCARG(uap, rusage) && 651 (error = copyout((caddr_t)p->p_ru, 652 (caddr_t)SCARG(uap, rusage), 653 sizeof(struct rusage)))) 654 return (error); 655 /* 656 * If we got the child via ptrace(2) or procfs, and 657 * the parent is different (meaning the process was 658 * attached, rather than run as a child), then we need 659 * to give it back to the old parent, and send the 660 * parent the exit signal. The rest of the cleanup 661 * will be done when the old parent waits on the child. 662 */ 663 if ((p->p_flag & P_TRACED) && p->p_opptr != p->p_pptr){ 664 t = p->p_opptr; 665 proc_reparent(p, t ? t : initproc); 666 p->p_opptr = NULL; 667 p->p_flag &= ~(P_TRACED|P_WAITED|P_FSTRACE); 668 if (p->p_exitsig != 0) 669 psignal(p->p_pptr, P_EXITSIG(p)); 670 wakeup((caddr_t)p->p_pptr); 671 return (0); 672 } 673 scheduler_wait_hook(q, p); 674 p->p_xstat = 0; 675 ruadd(&q->p_stats->p_cru, p->p_ru); 676 pool_put(&rusage_pool, p->p_ru); 677 678 /* 679 * Finally finished with old proc entry. 680 * Unlink it from its process group and free it. 681 */ 682 leavepgrp(p); 683 684 s = proclist_lock_write(); 685 LIST_REMOVE(p, p_list); /* off zombproc */ 686 proclist_unlock_write(s); 687 688 LIST_REMOVE(p, p_sibling); 689 690 /* 691 * Decrement the count of procs running with this uid. 692 */ 693 (void)chgproccnt(p->p_cred->p_ruid, -1); 694 695 /* 696 * Free up credentials. 697 */ 698 if (--p->p_cred->p_refcnt == 0) { 699 crfree(p->p_cred->pc_ucred); 700 pool_put(&pcred_pool, p->p_cred); 701 } 702 703 /* 704 * Release reference to text vnode 705 */ 706 if (p->p_textvp) 707 vrele(p->p_textvp); 708 709 /* 710 * Release any SA state 711 */ 712 if (p->p_sa) { 713 free(p->p_sa->sa_stacks, M_SA); 714 pool_put(&sadata_pool, p->p_sa); 715 } 716 717 pool_put(&proc_pool, p); 718 nprocs--; 719 return (0); 720 } 721 if (p->p_stat == SSTOP && (p->p_flag & P_WAITED) == 0 && 722 (p->p_flag & P_TRACED || SCARG(uap, options) & WUNTRACED)) { 723 p->p_flag |= P_WAITED; 724 retval[0] = p->p_pid; 725 726 if (SCARG(uap, status)) { 727 status = W_STOPCODE(p->p_xstat); 728 error = copyout((caddr_t)&status, 729 (caddr_t)SCARG(uap, status), 730 sizeof(status)); 731 } else 732 error = 0; 733 return (error); 734 } 735 } 736 if (nfound == 0) 737 return (ECHILD); 738 if (SCARG(uap, options) & WNOHANG) { 739 retval[0] = 0; 740 return (0); 741 } 742 if ((error = tsleep((caddr_t)q, PWAIT | PCATCH, "wait", 0)) != 0) 743 return (error); 744 goto loop; 745 } 746 747 /* 748 * make process 'parent' the new parent of process 'child'. 749 */ 750 void 751 proc_reparent(struct proc *child, struct proc *parent) 752 { 753 754 if (child->p_pptr == parent) 755 return; 756 757 if (parent == initproc) 758 child->p_exitsig = SIGCHLD; 759 760 LIST_REMOVE(child, p_sibling); 761 LIST_INSERT_HEAD(&parent->p_children, child, p_sibling); 762 child->p_pptr = parent; 763 } 764