1 /*- 2 * SPDX-License-Identifier: BSD-4-Clause 3 * 4 * Copyright (c) 1982, 1986, 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * Copyright (c) 2005 Robert N. M. Watson 8 * All rights reserved. 9 * 10 * All or some portions of this file are derived from material licensed 11 * to the University of California by American Telephone and Telegraph 12 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 13 * the permission of UNIX System Laboratories, Inc. 14 * 15 * Redistribution and use in source and binary forms, with or without 16 * modification, are permitted provided that the following conditions 17 * are met: 18 * 1. Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 2. Redistributions in binary form must reproduce the above copyright 21 * notice, this list of conditions and the following disclaimer in the 22 * documentation and/or other materials provided with the distribution. 23 * 3. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * Copyright (c) 1994 Christopher G. Demetriou 40 * 41 * Redistribution and use in source and binary forms, with or without 42 * modification, are permitted provided that the following conditions 43 * are met: 44 * 1. Redistributions of source code must retain the above copyright 45 * notice, this list of conditions and the following disclaimer. 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in the 48 * documentation and/or other materials provided with the distribution. 49 * 3. All advertising materials mentioning features or use of this software 50 * must display the following acknowledgement: 51 * This product includes software developed by the University of 52 * California, Berkeley and its contributors. 53 * 4. Neither the name of the University nor the names of its contributors 54 * may be used to endorse or promote products derived from this software 55 * without specific prior written permission. 56 * 57 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 58 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 59 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 60 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 61 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 62 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 63 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 64 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 65 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 66 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 67 * SUCH DAMAGE. 68 * 69 * @(#)kern_acct.c 8.1 (Berkeley) 6/14/93 70 */ 71 72 #include <sys/cdefs.h> 73 __FBSDID("$FreeBSD$"); 74 75 #include <sys/param.h> 76 #include <sys/systm.h> 77 #include <sys/acct.h> 78 #include <sys/fcntl.h> 79 #include <sys/kernel.h> 80 #include <sys/kthread.h> 81 #include <sys/limits.h> 82 #include <sys/lock.h> 83 #include <sys/malloc.h> 84 #include <sys/mount.h> 85 #include <sys/mutex.h> 86 #include <sys/namei.h> 87 #include <sys/priv.h> 88 #include <sys/proc.h> 89 #include <sys/resourcevar.h> 90 #include <sys/sched.h> 91 #include <sys/sx.h> 92 #include <sys/sysctl.h> 93 #include <sys/sysent.h> 94 #include <sys/syslog.h> 95 #include <sys/sysproto.h> 96 #include <sys/tty.h> 97 #include <sys/vnode.h> 98 99 #include <security/mac/mac_framework.h> 100 101 _Static_assert(sizeof(struct acctv3) - offsetof(struct acctv3, ac_trailer) == 102 sizeof(struct acctv2) - offsetof(struct acctv2, ac_trailer), "trailer"); 103 _Static_assert(sizeof(struct acctv3) - offsetof(struct acctv3, ac_len2) == 104 sizeof(struct acctv2) - offsetof(struct acctv2, ac_len2), "len2"); 105 106 /* 107 * The routines implemented in this file are described in: 108 * Leffler, et al.: The Design and Implementation of the 4.3BSD 109 * UNIX Operating System (Addison Welley, 1989) 110 * on pages 62-63. 111 * On May 2007 the historic 3 bits base 8 exponent, 13 bit fraction 112 * compt_t representation described in the above reference was replaced 113 * with that of IEEE-754 floats. 114 * 115 * Arguably, to simplify accounting operations, this mechanism should 116 * be replaced by one in which an accounting log file (similar to /dev/klog) 117 * is read by a user process, etc. However, that has its own problems. 118 */ 119 120 /* Floating point definitions from <float.h>. */ 121 #define FLT_MANT_DIG 24 /* p */ 122 #define FLT_MAX_EXP 128 /* emax */ 123 124 /* 125 * Internal accounting functions. 126 * The former's operation is described in Leffler, et al., and the latter 127 * was provided by UCB with the 4.4BSD-Lite release 128 */ 129 static uint32_t encode_timeval(struct timeval); 130 static uint32_t encode_long(long); 131 static void acctwatch(void); 132 static void acct_thread(void *); 133 static int acct_disable(struct thread *, int); 134 135 /* 136 * Accounting vnode pointer, saved vnode pointer, and flags for each. 137 * acct_sx protects against changes to the active vnode and credentials 138 * while accounting records are being committed to disk. 139 */ 140 static int acct_configured; 141 static int acct_suspended; 142 static struct vnode *acct_vp; 143 static struct ucred *acct_cred; 144 static struct plimit *acct_limit; 145 static int acct_flags; 146 static struct sx acct_sx; 147 148 SX_SYSINIT(acct, &acct_sx, "acct_sx"); 149 150 /* 151 * State of the accounting kthread. 152 */ 153 static int acct_state; 154 155 #define ACCT_RUNNING 1 /* Accounting kthread is running. */ 156 #define ACCT_EXITREQ 2 /* Accounting kthread should exit. */ 157 158 /* 159 * Values associated with enabling and disabling accounting 160 */ 161 static int acctsuspend = 2; /* stop accounting when < 2% free space left */ 162 SYSCTL_INT(_kern, OID_AUTO, acct_suspend, CTLFLAG_RW, 163 &acctsuspend, 0, "percentage of free disk space below which accounting stops"); 164 165 static int acctresume = 4; /* resume when free space risen to > 4% */ 166 SYSCTL_INT(_kern, OID_AUTO, acct_resume, CTLFLAG_RW, 167 &acctresume, 0, "percentage of free disk space above which accounting resumes"); 168 169 static int acctchkfreq = 15; /* frequency (in seconds) to check space */ 170 171 static int 172 sysctl_acct_chkfreq(SYSCTL_HANDLER_ARGS) 173 { 174 int error, value; 175 176 /* Write out the old value. */ 177 error = SYSCTL_OUT(req, &acctchkfreq, sizeof(int)); 178 if (error || req->newptr == NULL) 179 return (error); 180 181 /* Read in and verify the new value. */ 182 error = SYSCTL_IN(req, &value, sizeof(int)); 183 if (error) 184 return (error); 185 if (value <= 0) 186 return (EINVAL); 187 acctchkfreq = value; 188 return (0); 189 } 190 SYSCTL_PROC(_kern, OID_AUTO, acct_chkfreq, 191 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &acctchkfreq, 0, 192 sysctl_acct_chkfreq, "I", 193 "frequency for checking the free space"); 194 195 SYSCTL_INT(_kern, OID_AUTO, acct_configured, CTLFLAG_RD, &acct_configured, 0, 196 "Accounting configured or not"); 197 198 SYSCTL_INT(_kern, OID_AUTO, acct_suspended, CTLFLAG_RD, &acct_suspended, 0, 199 "Accounting suspended or not"); 200 201 /* 202 * Accounting system call. Written based on the specification and previous 203 * implementation done by Mark Tinguely. 204 */ 205 int 206 sys_acct(struct thread *td, struct acct_args *uap) 207 { 208 struct nameidata nd; 209 int error, flags, i, replacing; 210 211 error = priv_check(td, PRIV_ACCT); 212 if (error) 213 return (error); 214 215 /* 216 * If accounting is to be started to a file, open that file for 217 * appending and make sure it's a 'normal'. 218 */ 219 if (uap->path != NULL) { 220 NDINIT(&nd, LOOKUP, NOFOLLOW | AUDITVNODE1, 221 UIO_USERSPACE, uap->path, td); 222 flags = FWRITE | O_APPEND; 223 error = vn_open(&nd, &flags, 0, NULL); 224 if (error) 225 return (error); 226 NDFREE(&nd, NDF_ONLY_PNBUF); 227 #ifdef MAC 228 error = mac_system_check_acct(td->td_ucred, nd.ni_vp); 229 if (error) { 230 VOP_UNLOCK(nd.ni_vp); 231 vn_close(nd.ni_vp, flags, td->td_ucred, td); 232 return (error); 233 } 234 #endif 235 VOP_UNLOCK(nd.ni_vp); 236 if (nd.ni_vp->v_type != VREG) { 237 vn_close(nd.ni_vp, flags, td->td_ucred, td); 238 return (EACCES); 239 } 240 #ifdef MAC 241 } else { 242 error = mac_system_check_acct(td->td_ucred, NULL); 243 if (error) 244 return (error); 245 #endif 246 } 247 248 /* 249 * Disallow concurrent access to the accounting vnode while we swap 250 * it out, in order to prevent access after close. 251 */ 252 sx_xlock(&acct_sx); 253 254 /* 255 * Don't log spurious disable/enable messages if we are 256 * switching from one accounting file to another due to log 257 * rotation. 258 */ 259 replacing = (acct_vp != NULL && uap->path != NULL); 260 261 /* 262 * If accounting was previously enabled, kill the old space-watcher, 263 * close the file, and (if no new file was specified, leave). Reset 264 * the suspended state regardless of whether accounting remains 265 * enabled. 266 */ 267 acct_suspended = 0; 268 if (acct_vp != NULL) 269 error = acct_disable(td, !replacing); 270 if (uap->path == NULL) { 271 if (acct_state & ACCT_RUNNING) { 272 acct_state |= ACCT_EXITREQ; 273 wakeup(&acct_state); 274 } 275 sx_xunlock(&acct_sx); 276 return (error); 277 } 278 279 /* 280 * Create our own plimit object without limits. It will be assigned 281 * to exiting processes. 282 */ 283 acct_limit = lim_alloc(); 284 for (i = 0; i < RLIM_NLIMITS; i++) 285 acct_limit->pl_rlimit[i].rlim_cur = 286 acct_limit->pl_rlimit[i].rlim_max = RLIM_INFINITY; 287 288 /* 289 * Save the new accounting file vnode, and schedule the new 290 * free space watcher. 291 */ 292 acct_vp = nd.ni_vp; 293 acct_cred = crhold(td->td_ucred); 294 acct_flags = flags; 295 if (acct_state & ACCT_RUNNING) 296 acct_state &= ~ACCT_EXITREQ; 297 else { 298 /* 299 * Try to start up an accounting kthread. We may start more 300 * than one, but if so the extras will commit suicide as 301 * soon as they start up. 302 */ 303 error = kproc_create(acct_thread, NULL, NULL, 0, 0, 304 "accounting"); 305 if (error) { 306 (void) acct_disable(td, 0); 307 sx_xunlock(&acct_sx); 308 log(LOG_NOTICE, "Unable to start accounting thread\n"); 309 return (error); 310 } 311 } 312 acct_configured = 1; 313 sx_xunlock(&acct_sx); 314 if (!replacing) 315 log(LOG_NOTICE, "Accounting enabled\n"); 316 return (error); 317 } 318 319 /* 320 * Disable currently in-progress accounting by closing the vnode, dropping 321 * our reference to the credential, and clearing the vnode's flags. 322 */ 323 static int 324 acct_disable(struct thread *td, int logging) 325 { 326 int error; 327 328 sx_assert(&acct_sx, SX_XLOCKED); 329 error = vn_close(acct_vp, acct_flags, acct_cred, td); 330 crfree(acct_cred); 331 lim_free(acct_limit); 332 acct_configured = 0; 333 acct_vp = NULL; 334 acct_cred = NULL; 335 acct_flags = 0; 336 if (logging) 337 log(LOG_NOTICE, "Accounting disabled\n"); 338 return (error); 339 } 340 341 /* 342 * Write out process accounting information, on process exit. 343 * Data to be written out is specified in Leffler, et al. 344 * and are enumerated below. (They're also noted in the system 345 * "acct.h" header file.) 346 */ 347 int 348 acct_process(struct thread *td) 349 { 350 struct acctv3 acct; 351 struct timeval ut, st, tmp; 352 struct plimit *oldlim; 353 struct proc *p; 354 struct rusage ru; 355 int t, ret; 356 357 /* 358 * Lockless check of accounting condition before doing the hard 359 * work. 360 */ 361 if (acct_vp == NULL || acct_suspended) 362 return (0); 363 364 sx_slock(&acct_sx); 365 366 /* 367 * If accounting isn't enabled, don't bother. Have to check again 368 * once we own the lock in case we raced with disabling of accounting 369 * by another thread. 370 */ 371 if (acct_vp == NULL || acct_suspended) { 372 sx_sunlock(&acct_sx); 373 return (0); 374 } 375 376 p = td->td_proc; 377 378 /* 379 * Get process accounting information. 380 */ 381 382 sx_slock(&proctree_lock); 383 PROC_LOCK(p); 384 385 /* (1) The terminal from which the process was started */ 386 if ((p->p_flag & P_CONTROLT) && p->p_pgrp->pg_session->s_ttyp) 387 acct.ac_tty = tty_udev(p->p_pgrp->pg_session->s_ttyp); 388 else 389 acct.ac_tty = NODEV; 390 sx_sunlock(&proctree_lock); 391 392 /* (2) The name of the command that ran */ 393 bcopy(p->p_comm, acct.ac_comm, sizeof acct.ac_comm); 394 395 /* (3) The amount of user and system time that was used */ 396 rufetchcalc(p, &ru, &ut, &st); 397 acct.ac_utime = encode_timeval(ut); 398 acct.ac_stime = encode_timeval(st); 399 400 /* (4) The elapsed time the command ran (and its starting time) */ 401 getboottime(&tmp); 402 timevaladd(&tmp, &p->p_stats->p_start); 403 acct.ac_btime = tmp.tv_sec; 404 microuptime(&tmp); 405 timevalsub(&tmp, &p->p_stats->p_start); 406 acct.ac_etime = encode_timeval(tmp); 407 408 /* (5) The average amount of memory used */ 409 tmp = ut; 410 timevaladd(&tmp, &st); 411 /* Convert tmp (i.e. u + s) into hz units to match ru_i*. */ 412 t = tmp.tv_sec * hz + tmp.tv_usec / tick; 413 if (t) 414 acct.ac_mem = encode_long((ru.ru_ixrss + ru.ru_idrss + 415 + ru.ru_isrss) / t); 416 else 417 acct.ac_mem = 0; 418 419 /* (6) The number of disk I/O operations done */ 420 acct.ac_io = encode_long(ru.ru_inblock + ru.ru_oublock); 421 422 /* (7) The UID and GID of the process */ 423 acct.ac_uid = p->p_ucred->cr_ruid; 424 acct.ac_gid = p->p_ucred->cr_rgid; 425 426 /* (8) The boolean flags that tell how the process terminated, etc. */ 427 acct.ac_flagx = p->p_acflag; 428 429 /* Setup ancillary structure fields. */ 430 acct.ac_flagx |= ANVER; 431 acct.ac_zero = 0; 432 acct.ac_version = 3; 433 acct.ac_len = acct.ac_len2 = sizeof(acct); 434 435 /* 436 * Eliminate rlimits (file size limit in particular). 437 */ 438 oldlim = p->p_limit; 439 p->p_limit = lim_hold(acct_limit); 440 PROC_UNLOCK(p); 441 lim_free(oldlim); 442 443 /* 444 * Write the accounting information to the file. 445 */ 446 ret = vn_rdwr(UIO_WRITE, acct_vp, (caddr_t)&acct, sizeof (acct), 447 (off_t)0, UIO_SYSSPACE, IO_APPEND|IO_UNIT, acct_cred, NOCRED, 448 NULL, td); 449 sx_sunlock(&acct_sx); 450 return (ret); 451 } 452 453 /* FLOAT_CONVERSION_START (Regression testing; don't remove this line.) */ 454 455 /* Convert timevals and longs into IEEE-754 bit patterns. */ 456 457 /* Mantissa mask (MSB is implied, so subtract 1). */ 458 #define MANT_MASK ((1 << (FLT_MANT_DIG - 1)) - 1) 459 460 /* 461 * We calculate integer values to a precision of approximately 462 * 28 bits. 463 * This is high-enough precision to fill the 24 float bits 464 * and low-enough to avoid overflowing the 32 int bits. 465 */ 466 #define CALC_BITS 28 467 468 /* log_2(1000000). */ 469 #define LOG2_1M 20 470 471 /* 472 * Convert the elements of a timeval into a 32-bit word holding 473 * the bits of a IEEE-754 float. 474 * The float value represents the timeval's value in microsecond units. 475 */ 476 static uint32_t 477 encode_timeval(struct timeval tv) 478 { 479 int log2_s; 480 int val, exp; /* Unnormalized value and exponent */ 481 int norm_exp; /* Normalized exponent */ 482 int shift; 483 484 /* 485 * First calculate value and exponent to about CALC_BITS precision. 486 * Note that the following conditionals have been ordered so that 487 * the most common cases appear first. 488 */ 489 if (tv.tv_sec == 0) { 490 if (tv.tv_usec == 0) 491 return (0); 492 exp = 0; 493 val = tv.tv_usec; 494 } else { 495 /* 496 * Calculate the value to a precision of approximately 497 * CALC_BITS. 498 */ 499 log2_s = fls(tv.tv_sec) - 1; 500 if (log2_s + LOG2_1M < CALC_BITS) { 501 exp = 0; 502 val = 1000000 * tv.tv_sec + tv.tv_usec; 503 } else { 504 exp = log2_s + LOG2_1M - CALC_BITS; 505 val = (unsigned int)(((uint64_t)1000000 * tv.tv_sec + 506 tv.tv_usec) >> exp); 507 } 508 } 509 /* Now normalize and pack the value into an IEEE-754 float. */ 510 norm_exp = fls(val) - 1; 511 shift = FLT_MANT_DIG - norm_exp - 1; 512 #ifdef ACCT_DEBUG 513 printf("val=%d exp=%d shift=%d log2(val)=%d\n", 514 val, exp, shift, norm_exp); 515 printf("exp=%x mant=%x\n", FLT_MAX_EXP - 1 + exp + norm_exp, 516 ((shift > 0 ? (val << shift) : (val >> -shift)) & MANT_MASK)); 517 #endif 518 return (((FLT_MAX_EXP - 1 + exp + norm_exp) << (FLT_MANT_DIG - 1)) | 519 ((shift > 0 ? val << shift : val >> -shift) & MANT_MASK)); 520 } 521 522 /* 523 * Convert a non-negative long value into the bit pattern of 524 * an IEEE-754 float value. 525 */ 526 static uint32_t 527 encode_long(long val) 528 { 529 int norm_exp; /* Normalized exponent */ 530 int shift; 531 532 if (val == 0) 533 return (0); 534 if (val < 0) { 535 log(LOG_NOTICE, 536 "encode_long: negative value %ld in accounting record\n", 537 val); 538 val = LONG_MAX; 539 } 540 norm_exp = fls(val) - 1; 541 shift = FLT_MANT_DIG - norm_exp - 1; 542 #ifdef ACCT_DEBUG 543 printf("val=%d shift=%d log2(val)=%d\n", 544 val, shift, norm_exp); 545 printf("exp=%x mant=%x\n", FLT_MAX_EXP - 1 + exp + norm_exp, 546 ((shift > 0 ? (val << shift) : (val >> -shift)) & MANT_MASK)); 547 #endif 548 return (((FLT_MAX_EXP - 1 + norm_exp) << (FLT_MANT_DIG - 1)) | 549 ((shift > 0 ? val << shift : val >> -shift) & MANT_MASK)); 550 } 551 552 /* FLOAT_CONVERSION_END (Regression testing; don't remove this line.) */ 553 554 /* 555 * Periodically check the filesystem to see if accounting 556 * should be turned on or off. Beware the case where the vnode 557 * has been vgone()'d out from underneath us, e.g. when the file 558 * system containing the accounting file has been forcibly unmounted. 559 */ 560 /* ARGSUSED */ 561 static void 562 acctwatch(void) 563 { 564 struct statfs *sp; 565 566 sx_assert(&acct_sx, SX_XLOCKED); 567 568 /* 569 * If accounting was disabled before our kthread was scheduled, 570 * then acct_vp might be NULL. If so, just ask our kthread to 571 * exit and return. 572 */ 573 if (acct_vp == NULL) { 574 acct_state |= ACCT_EXITREQ; 575 return; 576 } 577 578 /* 579 * If our vnode is no longer valid, tear it down and signal the 580 * accounting thread to die. 581 */ 582 if (acct_vp->v_type == VBAD) { 583 (void) acct_disable(NULL, 1); 584 acct_state |= ACCT_EXITREQ; 585 return; 586 } 587 588 /* 589 * Stopping here is better than continuing, maybe it will be VBAD 590 * next time around. 591 */ 592 sp = malloc(sizeof(struct statfs), M_STATFS, M_WAITOK); 593 if (VFS_STATFS(acct_vp->v_mount, sp) < 0) { 594 free(sp, M_STATFS); 595 return; 596 } 597 if (acct_suspended) { 598 if (sp->f_bavail > (int64_t)(acctresume * sp->f_blocks / 599 100)) { 600 acct_suspended = 0; 601 log(LOG_NOTICE, "Accounting resumed\n"); 602 } 603 } else { 604 if (sp->f_bavail <= (int64_t)(acctsuspend * sp->f_blocks / 605 100)) { 606 acct_suspended = 1; 607 log(LOG_NOTICE, "Accounting suspended\n"); 608 } 609 } 610 free(sp, M_STATFS); 611 } 612 613 /* 614 * The main loop for the dedicated kernel thread that periodically calls 615 * acctwatch(). 616 */ 617 static void 618 acct_thread(void *dummy) 619 { 620 u_char pri; 621 622 /* This is a low-priority kernel thread. */ 623 pri = PRI_MAX_KERN; 624 thread_lock(curthread); 625 sched_prio(curthread, pri); 626 thread_unlock(curthread); 627 628 /* If another accounting kthread is already running, just die. */ 629 sx_xlock(&acct_sx); 630 if (acct_state & ACCT_RUNNING) { 631 sx_xunlock(&acct_sx); 632 kproc_exit(0); 633 } 634 acct_state |= ACCT_RUNNING; 635 636 /* Loop until we are asked to exit. */ 637 while (!(acct_state & ACCT_EXITREQ)) { 638 639 /* Perform our periodic checks. */ 640 acctwatch(); 641 642 /* 643 * We check this flag again before sleeping since the 644 * acctwatch() might have shut down accounting and asked us 645 * to exit. 646 */ 647 if (!(acct_state & ACCT_EXITREQ)) { 648 sx_sleep(&acct_state, &acct_sx, 0, "-", 649 acctchkfreq * hz); 650 } 651 } 652 653 /* 654 * Acknowledge the exit request and shutdown. We clear both the 655 * exit request and running flags. 656 */ 657 acct_state = 0; 658 sx_xunlock(&acct_sx); 659 kproc_exit(0); 660 } 661