1 /* $OpenBSD: kern_fork.c,v 1.254 2024/01/15 15:47:37 mvs Exp $ */ 2 /* $NetBSD: kern_fork.c,v 1.29 1996/02/09 18:59:34 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_fork.c 8.6 (Berkeley) 4/8/94 38 */ 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/filedesc.h> 43 #include <sys/malloc.h> 44 #include <sys/mount.h> 45 #include <sys/proc.h> 46 #include <sys/resourcevar.h> 47 #include <sys/signalvar.h> 48 #include <sys/vnode.h> 49 #include <sys/vmmeter.h> 50 #include <sys/acct.h> 51 #include <sys/ktrace.h> 52 #include <sys/sched.h> 53 #include <sys/smr.h> 54 #include <sys/sysctl.h> 55 #include <sys/pool.h> 56 #include <sys/mman.h> 57 #include <sys/ptrace.h> 58 #include <sys/atomic.h> 59 #include <sys/unistd.h> 60 #include <sys/tracepoint.h> 61 62 #include <sys/syscallargs.h> 63 64 #include <uvm/uvm.h> 65 #include <machine/tcb.h> 66 67 int nprocesses = 1; /* process 0 */ 68 int nthreads = 1; /* proc 0 */ 69 struct forkstat forkstat; 70 71 void fork_return(void *); 72 pid_t alloctid(void); 73 pid_t allocpid(void); 74 int ispidtaken(pid_t); 75 76 void unveil_copy(struct process *parent, struct process *child); 77 78 struct proc *thread_new(struct proc *_parent, vaddr_t _uaddr); 79 struct process *process_new(struct proc *, struct process *, int); 80 int fork_check_maxthread(uid_t _uid); 81 82 void 83 fork_return(void *arg) 84 { 85 struct proc *p = (struct proc *)arg; 86 87 if (p->p_p->ps_flags & PS_TRACED) 88 psignal(p, SIGTRAP); 89 90 child_return(p); 91 } 92 93 int 94 sys_fork(struct proc *p, void *v, register_t *retval) 95 { 96 void (*func)(void *) = child_return; 97 int flags; 98 99 flags = FORK_FORK; 100 if (p->p_p->ps_ptmask & PTRACE_FORK) { 101 flags |= FORK_PTRACE; 102 func = fork_return; 103 } 104 return fork1(p, flags, func, NULL, retval, NULL); 105 } 106 107 int 108 sys_vfork(struct proc *p, void *v, register_t *retval) 109 { 110 return fork1(p, FORK_VFORK|FORK_PPWAIT, child_return, NULL, 111 retval, NULL); 112 } 113 114 int 115 sys___tfork(struct proc *p, void *v, register_t *retval) 116 { 117 struct sys___tfork_args /* { 118 syscallarg(const struct __tfork) *param; 119 syscallarg(size_t) psize; 120 } */ *uap = v; 121 size_t psize = SCARG(uap, psize); 122 struct __tfork param = { 0 }; 123 int error; 124 125 if (psize == 0 || psize > sizeof(param)) 126 return EINVAL; 127 if ((error = copyin(SCARG(uap, param), ¶m, psize))) 128 return error; 129 #ifdef KTRACE 130 if (KTRPOINT(p, KTR_STRUCT)) 131 ktrstruct(p, "tfork", ¶m, sizeof(param)); 132 #endif 133 #ifdef TCB_INVALID 134 if (TCB_INVALID(param.tf_tcb)) 135 return EINVAL; 136 #endif /* TCB_INVALID */ 137 138 return thread_fork(p, param.tf_stack, param.tf_tcb, param.tf_tid, 139 retval); 140 } 141 142 /* 143 * Allocate and initialize a thread (proc) structure, given the parent thread. 144 */ 145 struct proc * 146 thread_new(struct proc *parent, vaddr_t uaddr) 147 { 148 struct proc *p; 149 150 p = pool_get(&proc_pool, PR_WAITOK); 151 p->p_stat = SIDL; /* protect against others */ 152 p->p_runpri = 0; 153 p->p_flag = 0; 154 155 /* 156 * Make a proc table entry for the new process. 157 * Start by zeroing the section of proc that is zero-initialized, 158 * then copy the section that is copied directly from the parent. 159 */ 160 memset(&p->p_startzero, 0, 161 (caddr_t)&p->p_endzero - (caddr_t)&p->p_startzero); 162 memcpy(&p->p_startcopy, &parent->p_startcopy, 163 (caddr_t)&p->p_endcopy - (caddr_t)&p->p_startcopy); 164 crhold(p->p_ucred); 165 p->p_addr = (struct user *)uaddr; 166 167 /* 168 * Initialize the timeouts. 169 */ 170 timeout_set(&p->p_sleep_to, endtsleep, p); 171 172 return p; 173 } 174 175 /* 176 * Initialize common bits of a process structure, given the initial thread. 177 */ 178 void 179 process_initialize(struct process *pr, struct proc *p) 180 { 181 /* initialize the thread links */ 182 pr->ps_mainproc = p; 183 TAILQ_INIT(&pr->ps_threads); 184 TAILQ_INSERT_TAIL(&pr->ps_threads, p, p_thr_link); 185 pr->ps_threadcnt = 1; 186 p->p_p = pr; 187 188 /* give the process the same creds as the initial thread */ 189 pr->ps_ucred = p->p_ucred; 190 crhold(pr->ps_ucred); 191 /* new thread and new process */ 192 KASSERT(p->p_ucred->cr_refcnt.r_refs >= 2); 193 194 LIST_INIT(&pr->ps_children); 195 LIST_INIT(&pr->ps_orphans); 196 LIST_INIT(&pr->ps_ftlist); 197 LIST_INIT(&pr->ps_sigiolst); 198 TAILQ_INIT(&pr->ps_tslpqueue); 199 200 refcnt_init(&pr->ps_refcnt); 201 rw_init(&pr->ps_lock, "pslock"); 202 mtx_init(&pr->ps_mtx, IPL_HIGH); 203 204 timeout_set_flags(&pr->ps_realit_to, realitexpire, pr, 205 KCLOCK_UPTIME, 0); 206 timeout_set(&pr->ps_rucheck_to, rucheck, pr); 207 } 208 209 210 /* 211 * Allocate and initialize a new process. 212 */ 213 struct process * 214 process_new(struct proc *p, struct process *parent, int flags) 215 { 216 struct process *pr; 217 218 pr = pool_get(&process_pool, PR_WAITOK); 219 220 /* 221 * Make a process structure for the new process. 222 * Start by zeroing the section of proc that is zero-initialized, 223 * then copy the section that is copied directly from the parent. 224 */ 225 memset(&pr->ps_startzero, 0, 226 (caddr_t)&pr->ps_endzero - (caddr_t)&pr->ps_startzero); 227 memcpy(&pr->ps_startcopy, &parent->ps_startcopy, 228 (caddr_t)&pr->ps_endcopy - (caddr_t)&pr->ps_startcopy); 229 230 process_initialize(pr, p); 231 pr->ps_pid = allocpid(); 232 lim_fork(parent, pr); 233 234 /* post-copy fixups */ 235 pr->ps_pptr = parent; 236 pr->ps_ppid = parent->ps_pid; 237 238 /* bump references to the text vnode (for sysctl) */ 239 pr->ps_textvp = parent->ps_textvp; 240 if (pr->ps_textvp) 241 vref(pr->ps_textvp); 242 243 /* copy unveil if unveil is active */ 244 unveil_copy(parent, pr); 245 246 pr->ps_flags = parent->ps_flags & 247 (PS_SUGID | PS_SUGIDEXEC | PS_PLEDGE | PS_EXECPLEDGE | 248 PS_WXNEEDED | PS_CHROOT); 249 if (parent->ps_session->s_ttyvp != NULL) 250 pr->ps_flags |= parent->ps_flags & PS_CONTROLT; 251 252 /* 253 * Duplicate sub-structures as needed. 254 * Increase reference counts on shared objects. 255 */ 256 if (flags & FORK_SHAREFILES) 257 pr->ps_fd = fdshare(parent); 258 else 259 pr->ps_fd = fdcopy(parent); 260 pr->ps_sigacts = sigactsinit(parent); 261 if (flags & FORK_SHAREVM) 262 pr->ps_vmspace = uvmspace_share(parent); 263 else 264 pr->ps_vmspace = uvmspace_fork(parent); 265 266 if (parent->ps_flags & PS_PROFIL) 267 startprofclock(pr); 268 if (flags & FORK_PTRACE) 269 pr->ps_flags |= parent->ps_flags & PS_TRACED; 270 if (flags & FORK_NOZOMBIE) 271 pr->ps_flags |= PS_NOZOMBIE; 272 if (flags & FORK_SYSTEM) 273 pr->ps_flags |= PS_SYSTEM; 274 275 /* mark as embryo to protect against others */ 276 pr->ps_flags |= PS_EMBRYO; 277 278 /* Force visibility of all of the above changes */ 279 membar_producer(); 280 281 /* it's sufficiently inited to be globally visible */ 282 LIST_INSERT_HEAD(&allprocess, pr, ps_list); 283 284 return pr; 285 } 286 287 /* print the 'table full' message once per 10 seconds */ 288 struct timeval fork_tfmrate = { 10, 0 }; 289 290 int 291 fork_check_maxthread(uid_t uid) 292 { 293 /* 294 * Although process entries are dynamically created, we still keep 295 * a global limit on the maximum number we will create. We reserve 296 * the last 5 processes to root. The variable nprocesses is the 297 * current number of processes, maxprocess is the limit. Similar 298 * rules for threads (struct proc): we reserve the last 5 to root; 299 * the variable nthreads is the current number of procs, maxthread is 300 * the limit. 301 */ 302 if ((nthreads >= maxthread - 5 && uid != 0) || nthreads >= maxthread) { 303 static struct timeval lasttfm; 304 305 if (ratecheck(&lasttfm, &fork_tfmrate)) 306 tablefull("thread"); 307 return EAGAIN; 308 } 309 nthreads++; 310 311 return 0; 312 } 313 314 static inline void 315 fork_thread_start(struct proc *p, struct proc *parent, int flags) 316 { 317 struct cpu_info *ci; 318 int s; 319 320 SCHED_LOCK(s); 321 ci = sched_choosecpu_fork(parent, flags); 322 TRACEPOINT(sched, fork, p->p_tid + THREAD_PID_OFFSET, 323 p->p_p->ps_pid, CPU_INFO_UNIT(ci)); 324 setrunqueue(ci, p, p->p_usrpri); 325 SCHED_UNLOCK(s); 326 } 327 328 int 329 fork1(struct proc *curp, int flags, void (*func)(void *), void *arg, 330 register_t *retval, struct proc **rnewprocp) 331 { 332 struct process *curpr = curp->p_p; 333 struct process *pr; 334 struct proc *p; 335 uid_t uid = curp->p_ucred->cr_ruid; 336 struct vmspace *vm; 337 int count; 338 vaddr_t uaddr; 339 int error; 340 struct ptrace_state *newptstat = NULL; 341 342 KASSERT((flags & ~(FORK_FORK | FORK_VFORK | FORK_PPWAIT | FORK_PTRACE 343 | FORK_IDLE | FORK_SHAREVM | FORK_SHAREFILES | FORK_NOZOMBIE 344 | FORK_SYSTEM)) == 0); 345 KASSERT(func != NULL); 346 347 if ((error = fork_check_maxthread(uid))) 348 return error; 349 350 if ((nprocesses >= maxprocess - 5 && uid != 0) || 351 nprocesses >= maxprocess) { 352 static struct timeval lasttfm; 353 354 if (ratecheck(&lasttfm, &fork_tfmrate)) 355 tablefull("process"); 356 nthreads--; 357 return EAGAIN; 358 } 359 nprocesses++; 360 361 /* 362 * Increment the count of processes running with this uid. 363 * Don't allow a nonprivileged user to exceed their current limit. 364 */ 365 count = chgproccnt(uid, 1); 366 if (uid != 0 && count > lim_cur(RLIMIT_NPROC)) { 367 (void)chgproccnt(uid, -1); 368 nprocesses--; 369 nthreads--; 370 return EAGAIN; 371 } 372 373 uaddr = uvm_uarea_alloc(); 374 if (uaddr == 0) { 375 (void)chgproccnt(uid, -1); 376 nprocesses--; 377 nthreads--; 378 return (ENOMEM); 379 } 380 381 /* 382 * From now on, we're committed to the fork and cannot fail. 383 */ 384 p = thread_new(curp, uaddr); 385 pr = process_new(p, curpr, flags); 386 387 p->p_fd = pr->ps_fd; 388 p->p_vmspace = pr->ps_vmspace; 389 if (pr->ps_flags & PS_SYSTEM) 390 atomic_setbits_int(&p->p_flag, P_SYSTEM); 391 392 if (flags & FORK_PPWAIT) { 393 atomic_setbits_int(&pr->ps_flags, PS_PPWAIT); 394 atomic_setbits_int(&curpr->ps_flags, PS_ISPWAIT); 395 } 396 397 #ifdef KTRACE 398 /* 399 * Copy traceflag and tracefile if enabled. 400 * If not inherited, these were zeroed above. 401 */ 402 if (curpr->ps_traceflag & KTRFAC_INHERIT) 403 ktrsettrace(pr, curpr->ps_traceflag, curpr->ps_tracevp, 404 curpr->ps_tracecred); 405 #endif 406 407 /* 408 * Finish creating the child thread. cpu_fork() will copy 409 * and update the pcb and make the child ready to run. If 410 * this is a normal user fork, the child will exit directly 411 * to user mode via child_return() on its first time slice 412 * and will not return here. If this is a kernel thread, 413 * the specified entry point will be executed. 414 */ 415 cpu_fork(curp, p, NULL, NULL, func, arg ? arg : p); 416 417 vm = pr->ps_vmspace; 418 419 if (flags & FORK_FORK) { 420 forkstat.cntfork++; 421 forkstat.sizfork += vm->vm_dsize + vm->vm_ssize; 422 } else if (flags & FORK_VFORK) { 423 forkstat.cntvfork++; 424 forkstat.sizvfork += vm->vm_dsize + vm->vm_ssize; 425 } else { 426 forkstat.cntkthread++; 427 } 428 429 if (pr->ps_flags & PS_TRACED && flags & FORK_FORK) 430 newptstat = malloc(sizeof(*newptstat), M_SUBPROC, M_WAITOK); 431 432 p->p_tid = alloctid(); 433 434 LIST_INSERT_HEAD(&allproc, p, p_list); 435 LIST_INSERT_HEAD(TIDHASH(p->p_tid), p, p_hash); 436 LIST_INSERT_HEAD(PIDHASH(pr->ps_pid), pr, ps_hash); 437 LIST_INSERT_AFTER(curpr, pr, ps_pglist); 438 LIST_INSERT_HEAD(&curpr->ps_children, pr, ps_sibling); 439 440 if (pr->ps_flags & PS_TRACED) { 441 pr->ps_oppid = curpr->ps_pid; 442 process_reparent(pr, curpr->ps_pptr); 443 444 /* 445 * Set ptrace status. 446 */ 447 if (newptstat != NULL) { 448 pr->ps_ptstat = newptstat; 449 newptstat = NULL; 450 curpr->ps_ptstat->pe_report_event = PTRACE_FORK; 451 pr->ps_ptstat->pe_report_event = PTRACE_FORK; 452 curpr->ps_ptstat->pe_other_pid = pr->ps_pid; 453 pr->ps_ptstat->pe_other_pid = curpr->ps_pid; 454 } 455 } 456 457 /* 458 * For new processes, set accounting bits and mark as complete. 459 */ 460 nanouptime(&pr->ps_start); 461 pr->ps_acflag = AFORK; 462 atomic_clearbits_int(&pr->ps_flags, PS_EMBRYO); 463 464 if ((flags & FORK_IDLE) == 0) 465 fork_thread_start(p, curp, flags); 466 else 467 p->p_cpu = arg; 468 469 free(newptstat, M_SUBPROC, sizeof(*newptstat)); 470 471 /* 472 * Notify any interested parties about the new process. 473 */ 474 knote_locked(&curpr->ps_klist, NOTE_FORK | pr->ps_pid); 475 476 /* 477 * Update stats now that we know the fork was successful. 478 */ 479 uvmexp.forks++; 480 if (flags & FORK_PPWAIT) 481 uvmexp.forks_ppwait++; 482 if (flags & FORK_SHAREVM) 483 uvmexp.forks_sharevm++; 484 485 /* 486 * Pass a pointer to the new process to the caller. 487 */ 488 if (rnewprocp != NULL) 489 *rnewprocp = p; 490 491 /* 492 * Preserve synchronization semantics of vfork. If waiting for 493 * child to exec or exit, set PS_PPWAIT on child and PS_ISPWAIT 494 * on ourselves, and sleep on our process for the latter flag 495 * to go away. 496 * XXX Need to stop other rthreads in the parent 497 */ 498 if (flags & FORK_PPWAIT) 499 while (curpr->ps_flags & PS_ISPWAIT) 500 tsleep_nsec(curpr, PWAIT, "ppwait", INFSLP); 501 502 /* 503 * If we're tracing the child, alert the parent too. 504 */ 505 if ((flags & FORK_PTRACE) && (curpr->ps_flags & PS_TRACED)) 506 psignal(curp, SIGTRAP); 507 508 /* 509 * Return child pid to parent process 510 */ 511 if (retval != NULL) 512 *retval = pr->ps_pid; 513 return (0); 514 } 515 516 int 517 thread_fork(struct proc *curp, void *stack, void *tcb, pid_t *tidptr, 518 register_t *retval) 519 { 520 struct process *pr = curp->p_p; 521 struct proc *p; 522 pid_t tid; 523 vaddr_t uaddr; 524 int s, error; 525 526 if (stack == NULL) 527 return EINVAL; 528 529 if ((error = fork_check_maxthread(curp->p_ucred->cr_ruid))) 530 return error; 531 532 uaddr = uvm_uarea_alloc(); 533 if (uaddr == 0) { 534 nthreads--; 535 return ENOMEM; 536 } 537 538 /* 539 * From now on, we're committed to the fork and cannot fail. 540 */ 541 p = thread_new(curp, uaddr); 542 atomic_setbits_int(&p->p_flag, P_THREAD); 543 sigstkinit(&p->p_sigstk); 544 memset(p->p_name, 0, sizeof p->p_name); 545 546 /* other links */ 547 p->p_p = pr; 548 pr->ps_threadcnt++; 549 550 /* local copies */ 551 p->p_fd = pr->ps_fd; 552 p->p_vmspace = pr->ps_vmspace; 553 554 /* 555 * Finish creating the child thread. cpu_fork() will copy 556 * and update the pcb and make the child ready to run. The 557 * child will exit directly to user mode via child_return() 558 * on its first time slice and will not return here. 559 */ 560 cpu_fork(curp, p, stack, tcb, child_return, p); 561 562 p->p_tid = alloctid(); 563 564 LIST_INSERT_HEAD(&allproc, p, p_list); 565 LIST_INSERT_HEAD(TIDHASH(p->p_tid), p, p_hash); 566 567 SCHED_LOCK(s); 568 TAILQ_INSERT_TAIL(&pr->ps_threads, p, p_thr_link); 569 570 /* 571 * if somebody else wants to take us to single threaded mode, 572 * count ourselves in. 573 */ 574 if (pr->ps_single) { 575 atomic_inc_int(&pr->ps_singlecount); 576 atomic_setbits_int(&p->p_flag, P_SUSPSINGLE); 577 } 578 SCHED_UNLOCK(s); 579 580 /* 581 * Return tid to parent thread and copy it out to userspace 582 */ 583 *retval = tid = p->p_tid + THREAD_PID_OFFSET; 584 if (tidptr != NULL) { 585 if (copyout(&tid, tidptr, sizeof(tid))) 586 psignal(curp, SIGSEGV); 587 } 588 589 fork_thread_start(p, curp, 0); 590 591 /* 592 * Update stats now that we know the fork was successful. 593 */ 594 forkstat.cnttfork++; 595 uvmexp.forks++; 596 uvmexp.forks_sharevm++; 597 598 return 0; 599 } 600 601 602 /* Find an unused tid */ 603 pid_t 604 alloctid(void) 605 { 606 pid_t tid; 607 608 do { 609 /* (0 .. TID_MASK+1] */ 610 tid = 1 + (arc4random() & TID_MASK); 611 } while (tfind(tid) != NULL); 612 613 return (tid); 614 } 615 616 /* 617 * Checks for current use of a pid, either as a pid or pgid. 618 */ 619 pid_t oldpids[128]; 620 int 621 ispidtaken(pid_t pid) 622 { 623 uint32_t i; 624 625 for (i = 0; i < nitems(oldpids); i++) 626 if (pid == oldpids[i]) 627 return (1); 628 629 if (prfind(pid) != NULL) 630 return (1); 631 if (pgfind(pid) != NULL) 632 return (1); 633 if (zombiefind(pid) != NULL) 634 return (1); 635 return (0); 636 } 637 638 /* Find an unused pid */ 639 pid_t 640 allocpid(void) 641 { 642 static int first = 1; 643 pid_t pid; 644 645 /* The first PID allocated is always 1. */ 646 if (first) { 647 first = 0; 648 return 1; 649 } 650 651 /* 652 * All subsequent PIDs are chosen randomly. We need to 653 * find an unused PID in the range [2, PID_MAX]. 654 */ 655 do { 656 pid = 2 + arc4random_uniform(PID_MAX - 1); 657 } while (ispidtaken(pid)); 658 return pid; 659 } 660 661 void 662 freepid(pid_t pid) 663 { 664 static uint32_t idx; 665 666 oldpids[idx++ % nitems(oldpids)] = pid; 667 } 668 669 /* Do machine independent parts of switching to a new process */ 670 void 671 proc_trampoline_mi(void) 672 { 673 struct schedstate_percpu *spc = &curcpu()->ci_schedstate; 674 struct proc *p = curproc; 675 676 SCHED_ASSERT_LOCKED(); 677 678 clear_resched(curcpu()); 679 680 #if defined(MULTIPROCESSOR) 681 __mp_unlock(&sched_lock); 682 #endif 683 spl0(); 684 685 SCHED_ASSERT_UNLOCKED(); 686 KERNEL_ASSERT_UNLOCKED(); 687 assertwaitok(); 688 smr_idle(); 689 690 /* Start any optional clock interrupts needed by the thread. */ 691 if (ISSET(p->p_p->ps_flags, PS_ITIMER)) { 692 atomic_setbits_int(&spc->spc_schedflags, SPCF_ITIMER); 693 clockintr_advance(spc->spc_itimer, hardclock_period); 694 } 695 if (ISSET(p->p_p->ps_flags, PS_PROFIL)) { 696 atomic_setbits_int(&spc->spc_schedflags, SPCF_PROFCLOCK); 697 clockintr_advance(spc->spc_profclock, profclock_period); 698 } 699 700 nanouptime(&spc->spc_runtime); 701 KERNEL_LOCK(); 702 } 703