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 int acct_flags; 145 static struct sx acct_sx; 146 147 SX_SYSINIT(acct, &acct_sx, "acct_sx"); 148 149 /* 150 * State of the accounting kthread. 151 */ 152 static int acct_state; 153 154 #define ACCT_RUNNING 1 /* Accounting kthread is running. */ 155 #define ACCT_EXITREQ 2 /* Accounting kthread should exit. */ 156 157 /* 158 * Values associated with enabling and disabling accounting 159 */ 160 static int acctsuspend = 2; /* stop accounting when < 2% free space left */ 161 SYSCTL_INT(_kern, OID_AUTO, acct_suspend, CTLFLAG_RW, 162 &acctsuspend, 0, "percentage of free disk space below which accounting stops"); 163 164 static int acctresume = 4; /* resume when free space risen to > 4% */ 165 SYSCTL_INT(_kern, OID_AUTO, acct_resume, CTLFLAG_RW, 166 &acctresume, 0, "percentage of free disk space above which accounting resumes"); 167 168 static int acctchkfreq = 15; /* frequency (in seconds) to check space */ 169 170 static int 171 sysctl_acct_chkfreq(SYSCTL_HANDLER_ARGS) 172 { 173 int error, value; 174 175 /* Write out the old value. */ 176 error = SYSCTL_OUT(req, &acctchkfreq, sizeof(int)); 177 if (error || req->newptr == NULL) 178 return (error); 179 180 /* Read in and verify the new value. */ 181 error = SYSCTL_IN(req, &value, sizeof(int)); 182 if (error) 183 return (error); 184 if (value <= 0) 185 return (EINVAL); 186 acctchkfreq = value; 187 return (0); 188 } 189 SYSCTL_PROC(_kern, OID_AUTO, acct_chkfreq, 190 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, &acctchkfreq, 0, 191 sysctl_acct_chkfreq, "I", 192 "frequency for checking the free space"); 193 194 SYSCTL_INT(_kern, OID_AUTO, acct_configured, CTLFLAG_RD, &acct_configured, 0, 195 "Accounting configured or not"); 196 197 SYSCTL_INT(_kern, OID_AUTO, acct_suspended, CTLFLAG_RD, &acct_suspended, 0, 198 "Accounting suspended or not"); 199 200 /* 201 * Accounting system call. Written based on the specification and previous 202 * implementation done by Mark Tinguely. 203 */ 204 int 205 sys_acct(struct thread *td, struct acct_args *uap) 206 { 207 struct nameidata nd; 208 int error, flags, replacing; 209 210 error = priv_check(td, PRIV_ACCT); 211 if (error) 212 return (error); 213 214 /* 215 * If accounting is to be started to a file, open that file for 216 * appending and make sure it's a 'normal'. 217 */ 218 if (uap->path != NULL) { 219 NDINIT(&nd, LOOKUP, NOFOLLOW | AUDITVNODE1, 220 UIO_USERSPACE, uap->path, td); 221 flags = FWRITE | O_APPEND; 222 error = vn_open(&nd, &flags, 0, NULL); 223 if (error) 224 return (error); 225 NDFREE(&nd, NDF_ONLY_PNBUF); 226 #ifdef MAC 227 error = mac_system_check_acct(td->td_ucred, nd.ni_vp); 228 if (error) { 229 VOP_UNLOCK(nd.ni_vp); 230 vn_close(nd.ni_vp, flags, td->td_ucred, td); 231 return (error); 232 } 233 #endif 234 VOP_UNLOCK(nd.ni_vp); 235 if (nd.ni_vp->v_type != VREG) { 236 vn_close(nd.ni_vp, flags, td->td_ucred, td); 237 return (EACCES); 238 } 239 #ifdef MAC 240 } else { 241 error = mac_system_check_acct(td->td_ucred, NULL); 242 if (error) 243 return (error); 244 #endif 245 } 246 247 /* 248 * Disallow concurrent access to the accounting vnode while we swap 249 * it out, in order to prevent access after close. 250 */ 251 sx_xlock(&acct_sx); 252 253 /* 254 * Don't log spurious disable/enable messages if we are 255 * switching from one accounting file to another due to log 256 * rotation. 257 */ 258 replacing = (acct_vp != NULL && uap->path != NULL); 259 260 /* 261 * If accounting was previously enabled, kill the old space-watcher, 262 * close the file, and (if no new file was specified, leave). Reset 263 * the suspended state regardless of whether accounting remains 264 * enabled. 265 */ 266 acct_suspended = 0; 267 if (acct_vp != NULL) 268 error = acct_disable(td, !replacing); 269 if (uap->path == NULL) { 270 if (acct_state & ACCT_RUNNING) { 271 acct_state |= ACCT_EXITREQ; 272 wakeup(&acct_state); 273 } 274 sx_xunlock(&acct_sx); 275 return (error); 276 } 277 278 /* 279 * Save the new accounting file vnode, and schedule the new 280 * free space watcher. 281 */ 282 acct_vp = nd.ni_vp; 283 acct_cred = crhold(td->td_ucred); 284 acct_flags = flags; 285 if (acct_state & ACCT_RUNNING) 286 acct_state &= ~ACCT_EXITREQ; 287 else { 288 /* 289 * Try to start up an accounting kthread. We may start more 290 * than one, but if so the extras will commit suicide as 291 * soon as they start up. 292 */ 293 error = kproc_create(acct_thread, NULL, NULL, 0, 0, 294 "accounting"); 295 if (error) { 296 (void) acct_disable(td, 0); 297 sx_xunlock(&acct_sx); 298 log(LOG_NOTICE, "Unable to start accounting thread\n"); 299 return (error); 300 } 301 } 302 acct_configured = 1; 303 sx_xunlock(&acct_sx); 304 if (!replacing) 305 log(LOG_NOTICE, "Accounting enabled\n"); 306 return (error); 307 } 308 309 /* 310 * Disable currently in-progress accounting by closing the vnode, dropping 311 * our reference to the credential, and clearing the vnode's flags. 312 */ 313 static int 314 acct_disable(struct thread *td, int logging) 315 { 316 int error; 317 318 sx_assert(&acct_sx, SX_XLOCKED); 319 error = vn_close(acct_vp, acct_flags, acct_cred, td); 320 crfree(acct_cred); 321 acct_configured = 0; 322 acct_vp = NULL; 323 acct_cred = NULL; 324 acct_flags = 0; 325 if (logging) 326 log(LOG_NOTICE, "Accounting disabled\n"); 327 return (error); 328 } 329 330 /* 331 * Write out process accounting information, on process exit. 332 * Data to be written out is specified in Leffler, et al. 333 * and are enumerated below. (They're also noted in the system 334 * "acct.h" header file.) 335 */ 336 int 337 acct_process(struct thread *td) 338 { 339 struct acctv3 acct; 340 struct timeval ut, st, tmp; 341 struct proc *p; 342 struct rusage ru; 343 int t, ret; 344 345 /* 346 * Lockless check of accounting condition before doing the hard 347 * work. 348 */ 349 if (acct_vp == NULL || acct_suspended) 350 return (0); 351 352 memset(&acct, 0, sizeof(acct)); 353 354 sx_slock(&acct_sx); 355 356 /* 357 * If accounting isn't enabled, don't bother. Have to check again 358 * once we own the lock in case we raced with disabling of accounting 359 * by another thread. 360 */ 361 if (acct_vp == NULL || acct_suspended) { 362 sx_sunlock(&acct_sx); 363 return (0); 364 } 365 366 p = td->td_proc; 367 td->td_pflags2 |= TDP2_ACCT; 368 369 /* 370 * Get process accounting information. 371 */ 372 373 sx_slock(&proctree_lock); 374 PROC_LOCK(p); 375 376 /* (1) The terminal from which the process was started */ 377 if ((p->p_flag & P_CONTROLT) && p->p_pgrp->pg_session->s_ttyp) 378 acct.ac_tty = tty_udev(p->p_pgrp->pg_session->s_ttyp); 379 else 380 acct.ac_tty = NODEV; 381 sx_sunlock(&proctree_lock); 382 383 /* (2) The name of the command that ran */ 384 bcopy(p->p_comm, acct.ac_comm, sizeof acct.ac_comm); 385 386 /* (3) The amount of user and system time that was used */ 387 rufetchcalc(p, &ru, &ut, &st); 388 acct.ac_utime = encode_timeval(ut); 389 acct.ac_stime = encode_timeval(st); 390 391 /* (4) The elapsed time the command ran (and its starting time) */ 392 getboottime(&tmp); 393 timevaladd(&tmp, &p->p_stats->p_start); 394 acct.ac_btime = tmp.tv_sec; 395 microuptime(&tmp); 396 timevalsub(&tmp, &p->p_stats->p_start); 397 acct.ac_etime = encode_timeval(tmp); 398 399 /* (5) The average amount of memory used */ 400 tmp = ut; 401 timevaladd(&tmp, &st); 402 /* Convert tmp (i.e. u + s) into hz units to match ru_i*. */ 403 t = tmp.tv_sec * hz + tmp.tv_usec / tick; 404 if (t) 405 acct.ac_mem = encode_long((ru.ru_ixrss + ru.ru_idrss + 406 + ru.ru_isrss) / t); 407 else 408 acct.ac_mem = 0; 409 410 /* (6) The number of disk I/O operations done */ 411 acct.ac_io = encode_long(ru.ru_inblock + ru.ru_oublock); 412 413 /* (7) The UID and GID of the process */ 414 acct.ac_uid = p->p_ucred->cr_ruid; 415 acct.ac_gid = p->p_ucred->cr_rgid; 416 417 /* (8) The boolean flags that tell how the process terminated, etc. */ 418 acct.ac_flagx = p->p_acflag; 419 420 PROC_UNLOCK(p); 421 422 /* Setup ancillary structure fields. */ 423 acct.ac_flagx |= ANVER; 424 acct.ac_zero = 0; 425 acct.ac_version = 3; 426 acct.ac_len = acct.ac_len2 = sizeof(acct); 427 428 /* 429 * Write the accounting information to the file. 430 */ 431 ret = vn_rdwr(UIO_WRITE, acct_vp, (caddr_t)&acct, sizeof (acct), 432 (off_t)0, UIO_SYSSPACE, IO_APPEND|IO_UNIT, acct_cred, NOCRED, 433 NULL, td); 434 sx_sunlock(&acct_sx); 435 td->td_pflags2 &= ~TDP2_ACCT; 436 return (ret); 437 } 438 439 /* FLOAT_CONVERSION_START (Regression testing; don't remove this line.) */ 440 441 /* Convert timevals and longs into IEEE-754 bit patterns. */ 442 443 /* Mantissa mask (MSB is implied, so subtract 1). */ 444 #define MANT_MASK ((1 << (FLT_MANT_DIG - 1)) - 1) 445 446 /* 447 * We calculate integer values to a precision of approximately 448 * 28 bits. 449 * This is high-enough precision to fill the 24 float bits 450 * and low-enough to avoid overflowing the 32 int bits. 451 */ 452 #define CALC_BITS 28 453 454 /* log_2(1000000). */ 455 #define LOG2_1M 20 456 457 /* 458 * Convert the elements of a timeval into a 32-bit word holding 459 * the bits of a IEEE-754 float. 460 * The float value represents the timeval's value in microsecond units. 461 */ 462 static uint32_t 463 encode_timeval(struct timeval tv) 464 { 465 int log2_s; 466 int val, exp; /* Unnormalized value and exponent */ 467 int norm_exp; /* Normalized exponent */ 468 int shift; 469 470 /* 471 * First calculate value and exponent to about CALC_BITS precision. 472 * Note that the following conditionals have been ordered so that 473 * the most common cases appear first. 474 */ 475 if (tv.tv_sec == 0) { 476 if (tv.tv_usec == 0) 477 return (0); 478 exp = 0; 479 val = tv.tv_usec; 480 } else { 481 /* 482 * Calculate the value to a precision of approximately 483 * CALC_BITS. 484 */ 485 log2_s = fls(tv.tv_sec) - 1; 486 if (log2_s + LOG2_1M < CALC_BITS) { 487 exp = 0; 488 val = 1000000 * tv.tv_sec + tv.tv_usec; 489 } else { 490 exp = log2_s + LOG2_1M - CALC_BITS; 491 val = (unsigned int)(((uint64_t)1000000 * tv.tv_sec + 492 tv.tv_usec) >> exp); 493 } 494 } 495 /* Now normalize and pack the value into an IEEE-754 float. */ 496 norm_exp = fls(val) - 1; 497 shift = FLT_MANT_DIG - norm_exp - 1; 498 #ifdef ACCT_DEBUG 499 printf("val=%d exp=%d shift=%d log2(val)=%d\n", 500 val, exp, shift, norm_exp); 501 printf("exp=%x mant=%x\n", FLT_MAX_EXP - 1 + exp + norm_exp, 502 ((shift > 0 ? (val << shift) : (val >> -shift)) & MANT_MASK)); 503 #endif 504 return (((FLT_MAX_EXP - 1 + exp + norm_exp) << (FLT_MANT_DIG - 1)) | 505 ((shift > 0 ? val << shift : val >> -shift) & MANT_MASK)); 506 } 507 508 /* 509 * Convert a non-negative long value into the bit pattern of 510 * an IEEE-754 float value. 511 */ 512 static uint32_t 513 encode_long(long val) 514 { 515 int norm_exp; /* Normalized exponent */ 516 int shift; 517 518 if (val == 0) 519 return (0); 520 if (val < 0) { 521 log(LOG_NOTICE, 522 "encode_long: negative value %ld in accounting record\n", 523 val); 524 val = LONG_MAX; 525 } 526 norm_exp = fls(val) - 1; 527 shift = FLT_MANT_DIG - norm_exp - 1; 528 #ifdef ACCT_DEBUG 529 printf("val=%d shift=%d log2(val)=%d\n", 530 val, shift, norm_exp); 531 printf("exp=%x mant=%x\n", FLT_MAX_EXP - 1 + exp + norm_exp, 532 ((shift > 0 ? (val << shift) : (val >> -shift)) & MANT_MASK)); 533 #endif 534 return (((FLT_MAX_EXP - 1 + norm_exp) << (FLT_MANT_DIG - 1)) | 535 ((shift > 0 ? val << shift : val >> -shift) & MANT_MASK)); 536 } 537 538 /* FLOAT_CONVERSION_END (Regression testing; don't remove this line.) */ 539 540 /* 541 * Periodically check the filesystem to see if accounting 542 * should be turned on or off. Beware the case where the vnode 543 * has been vgone()'d out from underneath us, e.g. when the file 544 * system containing the accounting file has been forcibly unmounted. 545 */ 546 /* ARGSUSED */ 547 static void 548 acctwatch(void) 549 { 550 struct statfs *sp; 551 552 sx_assert(&acct_sx, SX_XLOCKED); 553 554 /* 555 * If accounting was disabled before our kthread was scheduled, 556 * then acct_vp might be NULL. If so, just ask our kthread to 557 * exit and return. 558 */ 559 if (acct_vp == NULL) { 560 acct_state |= ACCT_EXITREQ; 561 return; 562 } 563 564 /* 565 * If our vnode is no longer valid, tear it down and signal the 566 * accounting thread to die. 567 */ 568 if (acct_vp->v_type == VBAD) { 569 (void) acct_disable(NULL, 1); 570 acct_state |= ACCT_EXITREQ; 571 return; 572 } 573 574 /* 575 * Stopping here is better than continuing, maybe it will be VBAD 576 * next time around. 577 */ 578 sp = malloc(sizeof(struct statfs), M_STATFS, M_WAITOK); 579 if (VFS_STATFS(acct_vp->v_mount, sp) < 0) { 580 free(sp, M_STATFS); 581 return; 582 } 583 if (acct_suspended) { 584 if (sp->f_bavail > (int64_t)(acctresume * sp->f_blocks / 585 100)) { 586 acct_suspended = 0; 587 log(LOG_NOTICE, "Accounting resumed\n"); 588 } 589 } else { 590 if (sp->f_bavail <= (int64_t)(acctsuspend * sp->f_blocks / 591 100)) { 592 acct_suspended = 1; 593 log(LOG_NOTICE, "Accounting suspended\n"); 594 } 595 } 596 free(sp, M_STATFS); 597 } 598 599 /* 600 * The main loop for the dedicated kernel thread that periodically calls 601 * acctwatch(). 602 */ 603 static void 604 acct_thread(void *dummy) 605 { 606 u_char pri; 607 608 /* This is a low-priority kernel thread. */ 609 pri = PRI_MAX_KERN; 610 thread_lock(curthread); 611 sched_prio(curthread, pri); 612 thread_unlock(curthread); 613 614 /* If another accounting kthread is already running, just die. */ 615 sx_xlock(&acct_sx); 616 if (acct_state & ACCT_RUNNING) { 617 sx_xunlock(&acct_sx); 618 kproc_exit(0); 619 } 620 acct_state |= ACCT_RUNNING; 621 622 /* Loop until we are asked to exit. */ 623 while (!(acct_state & ACCT_EXITREQ)) { 624 /* Perform our periodic checks. */ 625 acctwatch(); 626 627 /* 628 * We check this flag again before sleeping since the 629 * acctwatch() might have shut down accounting and asked us 630 * to exit. 631 */ 632 if (!(acct_state & ACCT_EXITREQ)) { 633 sx_sleep(&acct_state, &acct_sx, 0, "-", 634 acctchkfreq * hz); 635 } 636 } 637 638 /* 639 * Acknowledge the exit request and shutdown. We clear both the 640 * exit request and running flags. 641 */ 642 acct_state = 0; 643 sx_xunlock(&acct_sx); 644 kproc_exit(0); 645 } 646