1 /* $OpenBSD: kern_exit.c,v 1.203 2022/03/31 01:41:22 millert Exp $ */ 2 /* $NetBSD: kern_exit.c,v 1.39 1996/04/22 01:38:25 christos Exp $ */ 3 4 /* 5 * Copyright (c) 1982, 1986, 1989, 1991, 1993 6 * The Regents of the University of California. All rights reserved. 7 * (c) UNIX System Laboratories, Inc. 8 * All or some portions of this file are derived from material licensed 9 * to the University of California by American Telephone and Telegraph 10 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 11 * the permission of UNIX System Laboratories, Inc. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * @(#)kern_exit.c 8.7 (Berkeley) 2/12/94 38 */ 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/ioctl.h> 43 #include <sys/proc.h> 44 #include <sys/tty.h> 45 #include <sys/time.h> 46 #include <sys/resource.h> 47 #include <sys/kernel.h> 48 #include <sys/sysctl.h> 49 #include <sys/wait.h> 50 #include <sys/vnode.h> 51 #include <sys/syslog.h> 52 #include <sys/malloc.h> 53 #include <sys/resourcevar.h> 54 #include <sys/ptrace.h> 55 #include <sys/acct.h> 56 #include <sys/filedesc.h> 57 #include <sys/signalvar.h> 58 #include <sys/sched.h> 59 #include <sys/ktrace.h> 60 #include <sys/pool.h> 61 #include <sys/mutex.h> 62 #include <sys/pledge.h> 63 #ifdef SYSVSEM 64 #include <sys/sem.h> 65 #endif 66 #include <sys/witness.h> 67 68 #include <sys/mount.h> 69 #include <sys/syscallargs.h> 70 71 #include <uvm/uvm_extern.h> 72 73 #include "kcov.h" 74 #if NKCOV > 0 75 #include <sys/kcov.h> 76 #endif 77 78 void proc_finish_wait(struct proc *, struct proc *); 79 void process_clear_orphan(struct process *); 80 void process_zap(struct process *); 81 void proc_free(struct proc *); 82 void unveil_destroy(struct process *ps); 83 84 /* 85 * exit -- 86 * Death of process. 87 */ 88 int 89 sys_exit(struct proc *p, void *v, register_t *retval) 90 { 91 struct sys_exit_args /* { 92 syscallarg(int) rval; 93 } */ *uap = v; 94 95 exit1(p, SCARG(uap, rval), 0, EXIT_NORMAL); 96 /* NOTREACHED */ 97 return (0); 98 } 99 100 int 101 sys___threxit(struct proc *p, void *v, register_t *retval) 102 { 103 struct sys___threxit_args /* { 104 syscallarg(pid_t *) notdead; 105 } */ *uap = v; 106 107 if (SCARG(uap, notdead) != NULL) { 108 pid_t zero = 0; 109 if (copyout(&zero, SCARG(uap, notdead), sizeof(zero))) 110 psignal(p, SIGSEGV); 111 } 112 exit1(p, 0, 0, EXIT_THREAD); 113 114 return (0); 115 } 116 117 /* 118 * Exit: deallocate address space and other resources, change proc state 119 * to zombie, and unlink proc from allproc and parent's lists. Save exit 120 * status and rusage for wait(). Check for child processes and orphan them. 121 */ 122 void 123 exit1(struct proc *p, int xexit, int xsig, int flags) 124 { 125 struct process *pr, *qr, *nqr; 126 struct rusage *rup; 127 int s; 128 129 atomic_setbits_int(&p->p_flag, P_WEXIT); 130 131 pr = p->p_p; 132 133 /* single-threaded? */ 134 if (!P_HASSIBLING(p)) { 135 flags = EXIT_NORMAL; 136 } else { 137 /* nope, multi-threaded */ 138 if (flags == EXIT_NORMAL) 139 single_thread_set(p, SINGLE_EXIT, 1); 140 else if (flags == EXIT_THREAD) 141 single_thread_check(p, 0); 142 } 143 144 if (flags == EXIT_NORMAL && !(pr->ps_flags & PS_EXITING)) { 145 if (pr->ps_pid == 1) 146 panic("init died (signal %d, exit %d)", xsig, xexit); 147 148 atomic_setbits_int(&pr->ps_flags, PS_EXITING); 149 pr->ps_xexit = xexit; 150 pr->ps_xsig = xsig; 151 152 /* 153 * If parent is waiting for us to exit or exec, PS_PPWAIT 154 * is set; we wake up the parent early to avoid deadlock. 155 */ 156 if (pr->ps_flags & PS_PPWAIT) { 157 atomic_clearbits_int(&pr->ps_flags, PS_PPWAIT); 158 atomic_clearbits_int(&pr->ps_pptr->ps_flags, 159 PS_ISPWAIT); 160 wakeup(pr->ps_pptr); 161 } 162 } 163 164 /* unlink ourselves from the active threads */ 165 SCHED_LOCK(s); 166 TAILQ_REMOVE(&pr->ps_threads, p, p_thr_link); 167 SCHED_UNLOCK(s); 168 if ((p->p_flag & P_THREAD) == 0) { 169 /* main thread gotta wait because it has the pid, et al */ 170 while (pr->ps_refcnt > 1) 171 tsleep_nsec(&pr->ps_threads, PWAIT, "thrdeath", INFSLP); 172 if (pr->ps_flags & PS_PROFIL) 173 stopprofclock(pr); 174 } 175 176 rup = pr->ps_ru; 177 if (rup == NULL) { 178 rup = pool_get(&rusage_pool, PR_WAITOK | PR_ZERO); 179 if (pr->ps_ru == NULL) { 180 pr->ps_ru = rup; 181 } else { 182 pool_put(&rusage_pool, rup); 183 rup = pr->ps_ru; 184 } 185 } 186 p->p_siglist = 0; 187 if ((p->p_flag & P_THREAD) == 0) 188 pr->ps_siglist = 0; 189 190 kqpoll_exit(); 191 192 #if NKCOV > 0 193 kcov_exit(p); 194 #endif 195 196 if ((p->p_flag & P_THREAD) == 0) { 197 sigio_freelist(&pr->ps_sigiolst); 198 199 /* close open files and release open-file table */ 200 fdfree(p); 201 202 cancel_all_itimers(); 203 204 timeout_del(&pr->ps_rucheck_to); 205 #ifdef SYSVSEM 206 semexit(pr); 207 #endif 208 killjobc(pr); 209 #ifdef ACCOUNTING 210 acct_process(p); 211 #endif 212 213 #ifdef KTRACE 214 /* release trace file */ 215 if (pr->ps_tracevp) 216 ktrcleartrace(pr); 217 #endif 218 219 unveil_destroy(pr); 220 221 /* 222 * If parent has the SAS_NOCLDWAIT flag set, we're not 223 * going to become a zombie. 224 */ 225 if (pr->ps_pptr->ps_sigacts->ps_sigflags & SAS_NOCLDWAIT) 226 atomic_setbits_int(&pr->ps_flags, PS_NOZOMBIE); 227 } 228 229 p->p_fd = NULL; /* zap the thread's copy */ 230 231 /* 232 * Remove proc from pidhash chain and allproc so looking 233 * it up won't work. We will put the proc on the 234 * deadproc list later (using the p_hash member), and 235 * wake up the reaper when we do. If this is the last 236 * thread of a process that isn't PS_NOZOMBIE, we'll put 237 * the process on the zombprocess list below. 238 */ 239 /* 240 * NOTE: WE ARE NO LONGER ALLOWED TO SLEEP! 241 */ 242 p->p_stat = SDEAD; 243 244 LIST_REMOVE(p, p_hash); 245 LIST_REMOVE(p, p_list); 246 247 if ((p->p_flag & P_THREAD) == 0) { 248 LIST_REMOVE(pr, ps_hash); 249 LIST_REMOVE(pr, ps_list); 250 251 if ((pr->ps_flags & PS_NOZOMBIE) == 0) 252 LIST_INSERT_HEAD(&zombprocess, pr, ps_list); 253 else { 254 /* 255 * Not going to be a zombie, so it's now off all 256 * the lists scanned by ispidtaken(), so block 257 * fast reuse of the pid now. 258 */ 259 freepid(pr->ps_pid); 260 } 261 262 /* 263 * Reparent children to their original parent, in case 264 * they were being traced, or to init(8). 265 */ 266 qr = LIST_FIRST(&pr->ps_children); 267 if (qr) /* only need this if any child is S_ZOMB */ 268 wakeup(initprocess); 269 for (; qr != NULL; qr = nqr) { 270 nqr = LIST_NEXT(qr, ps_sibling); 271 /* 272 * Traced processes are killed since their 273 * existence means someone is screwing up. 274 */ 275 if (qr->ps_flags & PS_TRACED && 276 !(qr->ps_flags & PS_EXITING)) { 277 process_untrace(qr); 278 279 /* 280 * If single threading is active, 281 * direct the signal to the active 282 * thread to avoid deadlock. 283 */ 284 if (qr->ps_single) 285 ptsignal(qr->ps_single, SIGKILL, 286 STHREAD); 287 else 288 prsignal(qr, SIGKILL); 289 } else { 290 process_reparent(qr, initprocess); 291 } 292 } 293 294 /* 295 * Make sure orphans won't remember the exiting process. 296 */ 297 while ((qr = LIST_FIRST(&pr->ps_orphans)) != NULL) { 298 KASSERT(qr->ps_oppid == pr->ps_pid); 299 qr->ps_oppid = 0; 300 process_clear_orphan(qr); 301 } 302 } 303 304 /* add thread's accumulated rusage into the process's total */ 305 ruadd(rup, &p->p_ru); 306 tuagg(pr, p); 307 308 /* 309 * clear %cpu usage during swap 310 */ 311 p->p_pctcpu = 0; 312 313 if ((p->p_flag & P_THREAD) == 0) { 314 /* 315 * Final thread has died, so add on our children's rusage 316 * and calculate the total times 317 */ 318 calcru(&pr->ps_tu, &rup->ru_utime, &rup->ru_stime, NULL); 319 ruadd(rup, &pr->ps_cru); 320 321 /* 322 * Notify parent that we're gone. If we're not going to 323 * become a zombie, reparent to process 1 (init) so that 324 * we can wake our original parent to possibly unblock 325 * wait4() to return ECHILD. 326 */ 327 if (pr->ps_flags & PS_NOZOMBIE) { 328 struct process *ppr = pr->ps_pptr; 329 process_reparent(pr, initprocess); 330 wakeup(ppr); 331 } 332 } 333 334 /* just a thread? detach it from its process */ 335 if (p->p_flag & P_THREAD) { 336 /* scheduler_wait_hook(pr->ps_mainproc, p); XXX */ 337 if (--pr->ps_refcnt == 1) 338 wakeup(&pr->ps_threads); 339 KASSERT(pr->ps_refcnt > 0); 340 } 341 342 /* Release the thread's read reference of resource limit structure. */ 343 if (p->p_limit != NULL) { 344 struct plimit *limit; 345 346 limit = p->p_limit; 347 p->p_limit = NULL; 348 lim_free(limit); 349 } 350 351 /* 352 * Other substructures are freed from reaper and wait(). 353 */ 354 355 /* 356 * Finally, call machine-dependent code to switch to a new 357 * context (possibly the idle context). Once we are no longer 358 * using the dead process's vmspace and stack, exit2() will be 359 * called to schedule those resources to be released by the 360 * reaper thread. 361 * 362 * Note that cpu_exit() will end with a call equivalent to 363 * cpu_switch(), finishing our execution (pun intended). 364 */ 365 uvmexp.swtch++; 366 cpu_exit(p); 367 panic("cpu_exit returned"); 368 } 369 370 /* 371 * Locking of this proclist is special; it's accessed in a 372 * critical section of process exit, and thus locking it can't 373 * modify interrupt state. We use a simple spin lock for this 374 * proclist. We use the p_hash member to linkup to deadproc. 375 */ 376 struct mutex deadproc_mutex = 377 MUTEX_INITIALIZER_FLAGS(IPL_NONE, "deadproc", MTX_NOWITNESS); 378 struct proclist deadproc = LIST_HEAD_INITIALIZER(deadproc); 379 380 /* 381 * We are called from cpu_exit() once it is safe to schedule the 382 * dead process's resources to be freed. 383 * 384 * NOTE: One must be careful with locking in this routine. It's 385 * called from a critical section in machine-dependent code, so 386 * we should refrain from changing any interrupt state. 387 * 388 * We lock the deadproc list, place the proc on that list (using 389 * the p_hash member), and wake up the reaper. 390 */ 391 void 392 exit2(struct proc *p) 393 { 394 mtx_enter(&deadproc_mutex); 395 LIST_INSERT_HEAD(&deadproc, p, p_hash); 396 mtx_leave(&deadproc_mutex); 397 398 wakeup(&deadproc); 399 } 400 401 void 402 proc_free(struct proc *p) 403 { 404 crfree(p->p_ucred); 405 pool_put(&proc_pool, p); 406 nthreads--; 407 } 408 409 /* 410 * Process reaper. This is run by a kernel thread to free the resources 411 * of a dead process. Once the resources are free, the process becomes 412 * a zombie, and the parent is allowed to read the undead's status. 413 */ 414 void 415 reaper(void *arg) 416 { 417 struct proc *p; 418 419 KERNEL_UNLOCK(); 420 421 SCHED_ASSERT_UNLOCKED(); 422 423 for (;;) { 424 mtx_enter(&deadproc_mutex); 425 while ((p = LIST_FIRST(&deadproc)) == NULL) 426 msleep_nsec(&deadproc, &deadproc_mutex, PVM, "reaper", 427 INFSLP); 428 429 /* Remove us from the deadproc list. */ 430 LIST_REMOVE(p, p_hash); 431 mtx_leave(&deadproc_mutex); 432 433 WITNESS_THREAD_EXIT(p); 434 435 KERNEL_LOCK(); 436 437 /* 438 * Free the VM resources we're still holding on to. 439 * We must do this from a valid thread because doing 440 * so may block. 441 */ 442 uvm_uarea_free(p); 443 p->p_vmspace = NULL; /* zap the thread's copy */ 444 445 if (p->p_flag & P_THREAD) { 446 /* Just a thread */ 447 proc_free(p); 448 } else { 449 struct process *pr = p->p_p; 450 451 /* Release the rest of the process's vmspace */ 452 uvm_exit(pr); 453 454 if ((pr->ps_flags & PS_NOZOMBIE) == 0) { 455 /* Process is now a true zombie. */ 456 atomic_setbits_int(&pr->ps_flags, PS_ZOMBIE); 457 } 458 459 /* Notify listeners of our demise and clean up. */ 460 knote_processexit(pr); 461 462 if (pr->ps_flags & PS_ZOMBIE) { 463 /* Post SIGCHLD and wake up parent. */ 464 prsignal(pr->ps_pptr, SIGCHLD); 465 wakeup(pr->ps_pptr); 466 } else { 467 /* No one will wait for us, just zap it. */ 468 process_zap(pr); 469 } 470 } 471 472 KERNEL_UNLOCK(); 473 } 474 } 475 476 int 477 sys_wait4(struct proc *q, void *v, register_t *retval) 478 { 479 struct sys_wait4_args /* { 480 syscallarg(pid_t) pid; 481 syscallarg(int *) status; 482 syscallarg(int) options; 483 syscallarg(struct rusage *) rusage; 484 } */ *uap = v; 485 struct rusage ru; 486 int status, error; 487 488 error = dowait4(q, SCARG(uap, pid), 489 SCARG(uap, status) ? &status : NULL, 490 SCARG(uap, options), SCARG(uap, rusage) ? &ru : NULL, retval); 491 if (error == 0 && retval[0] > 0 && SCARG(uap, status)) { 492 error = copyout(&status, SCARG(uap, status), sizeof(status)); 493 } 494 if (error == 0 && retval[0] > 0 && SCARG(uap, rusage)) { 495 error = copyout(&ru, SCARG(uap, rusage), sizeof(ru)); 496 #ifdef KTRACE 497 if (error == 0 && KTRPOINT(q, KTR_STRUCT)) 498 ktrrusage(q, &ru); 499 #endif 500 } 501 return (error); 502 } 503 504 int 505 dowait4(struct proc *q, pid_t pid, int *statusp, int options, 506 struct rusage *rusage, register_t *retval) 507 { 508 int nfound; 509 struct process *pr; 510 struct proc *p; 511 int error; 512 513 if (pid == 0) 514 pid = -q->p_p->ps_pgid; 515 if (options &~ (WUNTRACED|WNOHANG|WCONTINUED)) 516 return (EINVAL); 517 518 loop: 519 nfound = 0; 520 LIST_FOREACH(pr, &q->p_p->ps_children, ps_sibling) { 521 if ((pr->ps_flags & PS_NOZOMBIE) || 522 (pid != WAIT_ANY && 523 pr->ps_pid != pid && 524 pr->ps_pgid != -pid)) 525 continue; 526 527 p = pr->ps_mainproc; 528 529 nfound++; 530 if (pr->ps_flags & PS_ZOMBIE) { 531 retval[0] = pr->ps_pid; 532 533 if (statusp != NULL) 534 *statusp = W_EXITCODE(pr->ps_xexit, 535 pr->ps_xsig); 536 if (rusage != NULL) 537 memcpy(rusage, pr->ps_ru, sizeof(*rusage)); 538 proc_finish_wait(q, p); 539 return (0); 540 } 541 if (pr->ps_flags & PS_TRACED && 542 (pr->ps_flags & PS_WAITED) == 0 && pr->ps_single && 543 pr->ps_single->p_stat == SSTOP && 544 (pr->ps_single->p_flag & P_SUSPSINGLE) == 0) { 545 if (single_thread_wait(pr, 0)) 546 goto loop; 547 548 atomic_setbits_int(&pr->ps_flags, PS_WAITED); 549 retval[0] = pr->ps_pid; 550 551 if (statusp != NULL) 552 *statusp = W_STOPCODE(pr->ps_xsig); 553 if (rusage != NULL) 554 memset(rusage, 0, sizeof(*rusage)); 555 return (0); 556 } 557 if (p->p_stat == SSTOP && 558 (pr->ps_flags & PS_WAITED) == 0 && 559 (p->p_flag & P_SUSPSINGLE) == 0 && 560 (pr->ps_flags & PS_TRACED || 561 options & WUNTRACED)) { 562 atomic_setbits_int(&pr->ps_flags, PS_WAITED); 563 retval[0] = pr->ps_pid; 564 565 if (statusp != NULL) 566 *statusp = W_STOPCODE(pr->ps_xsig); 567 if (rusage != NULL) 568 memset(rusage, 0, sizeof(*rusage)); 569 return (0); 570 } 571 if ((options & WCONTINUED) && (p->p_flag & P_CONTINUED)) { 572 atomic_clearbits_int(&p->p_flag, P_CONTINUED); 573 retval[0] = pr->ps_pid; 574 575 if (statusp != NULL) 576 *statusp = _WCONTINUED; 577 if (rusage != NULL) 578 memset(rusage, 0, sizeof(*rusage)); 579 return (0); 580 } 581 } 582 /* 583 * Look in the orphans list too, to allow the parent to 584 * collect its child's exit status even if child is being 585 * debugged. 586 * 587 * Debugger detaches from the parent upon successful 588 * switch-over from parent to child. At this point due to 589 * re-parenting the parent loses the child to debugger and a 590 * wait4(2) call would report that it has no children to wait 591 * for. By maintaining a list of orphans we allow the parent 592 * to successfully wait until the child becomes a zombie. 593 */ 594 if (nfound == 0) { 595 LIST_FOREACH(pr, &q->p_p->ps_orphans, ps_orphan) { 596 if ((pr->ps_flags & PS_NOZOMBIE) || 597 (pid != WAIT_ANY && 598 pr->ps_pid != pid && 599 pr->ps_pgid != -pid)) 600 continue; 601 nfound++; 602 break; 603 } 604 } 605 if (nfound == 0) 606 return (ECHILD); 607 if (options & WNOHANG) { 608 retval[0] = 0; 609 return (0); 610 } 611 if ((error = tsleep_nsec(q->p_p, PWAIT | PCATCH, "wait", INFSLP)) != 0) 612 return (error); 613 goto loop; 614 } 615 616 void 617 proc_finish_wait(struct proc *waiter, struct proc *p) 618 { 619 struct process *pr, *tr; 620 struct rusage *rup; 621 622 /* 623 * If we got the child via a ptrace 'attach', 624 * we need to give it back to the old parent. 625 */ 626 pr = p->p_p; 627 if (pr->ps_oppid != 0 && (pr->ps_oppid != pr->ps_pptr->ps_pid) && 628 (tr = prfind(pr->ps_oppid))) { 629 pr->ps_oppid = 0; 630 atomic_clearbits_int(&pr->ps_flags, PS_TRACED); 631 process_reparent(pr, tr); 632 prsignal(tr, SIGCHLD); 633 wakeup(tr); 634 } else { 635 scheduler_wait_hook(waiter, p); 636 rup = &waiter->p_p->ps_cru; 637 ruadd(rup, pr->ps_ru); 638 LIST_REMOVE(pr, ps_list); /* off zombprocess */ 639 freepid(pr->ps_pid); 640 process_zap(pr); 641 } 642 } 643 644 /* 645 * give process back to original parent or init(8) 646 */ 647 void 648 process_untrace(struct process *pr) 649 { 650 struct process *ppr = NULL; 651 652 KASSERT(pr->ps_flags & PS_TRACED); 653 654 if (pr->ps_oppid != 0 && 655 (pr->ps_oppid != pr->ps_pptr->ps_pid)) 656 ppr = prfind(pr->ps_oppid); 657 658 /* not being traced any more */ 659 pr->ps_oppid = 0; 660 atomic_clearbits_int(&pr->ps_flags, PS_TRACED); 661 process_reparent(pr, ppr ? ppr : initprocess); 662 } 663 664 void 665 process_clear_orphan(struct process *pr) 666 { 667 if (pr->ps_flags & PS_ORPHAN) { 668 LIST_REMOVE(pr, ps_orphan); 669 atomic_clearbits_int(&pr->ps_flags, PS_ORPHAN); 670 } 671 } 672 673 /* 674 * make process 'parent' the new parent of process 'child'. 675 */ 676 void 677 process_reparent(struct process *child, struct process *parent) 678 { 679 680 if (child->ps_pptr == parent) 681 return; 682 683 KASSERT(child->ps_oppid == 0 || 684 child->ps_oppid == child->ps_pptr->ps_pid); 685 686 LIST_REMOVE(child, ps_sibling); 687 LIST_INSERT_HEAD(&parent->ps_children, child, ps_sibling); 688 689 process_clear_orphan(child); 690 if (child->ps_flags & PS_TRACED) { 691 atomic_setbits_int(&child->ps_flags, PS_ORPHAN); 692 LIST_INSERT_HEAD(&child->ps_pptr->ps_orphans, child, ps_orphan); 693 } 694 695 child->ps_pptr = parent; 696 child->ps_ppid = parent->ps_pid; 697 } 698 699 void 700 process_zap(struct process *pr) 701 { 702 struct vnode *otvp; 703 struct proc *p = pr->ps_mainproc; 704 705 /* 706 * Finally finished with old proc entry. 707 * Unlink it from its process group and free it. 708 */ 709 leavepgrp(pr); 710 LIST_REMOVE(pr, ps_sibling); 711 process_clear_orphan(pr); 712 713 /* 714 * Decrement the count of procs running with this uid. 715 */ 716 (void)chgproccnt(pr->ps_ucred->cr_ruid, -1); 717 718 /* 719 * Release reference to text vnode 720 */ 721 otvp = pr->ps_textvp; 722 pr->ps_textvp = NULL; 723 if (otvp) 724 vrele(otvp); 725 726 KASSERT(pr->ps_refcnt == 1); 727 if (pr->ps_ptstat != NULL) 728 free(pr->ps_ptstat, M_SUBPROC, sizeof(*pr->ps_ptstat)); 729 pool_put(&rusage_pool, pr->ps_ru); 730 KASSERT(TAILQ_EMPTY(&pr->ps_threads)); 731 sigactsfree(pr->ps_sigacts); 732 lim_free(pr->ps_limit); 733 crfree(pr->ps_ucred); 734 pool_put(&process_pool, pr); 735 nprocesses--; 736 737 proc_free(p); 738 } 739