1 /* $NetBSD: subr_iostat.c,v 1.24 2018/09/03 16:29:35 riastradh Exp $ */ 2 /* NetBSD: subr_disk.c,v 1.69 2005/05/29 22:24:15 christos Exp */ 3 4 /*- 5 * Copyright (c) 1996, 1997, 1999, 2000, 2009 The NetBSD Foundation, Inc. 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to The NetBSD Foundation 9 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 10 * NASA Ames Research Center. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 23 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 24 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 * POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 /* 35 * Copyright (c) 1982, 1986, 1988, 1993 36 * The Regents of the University of California. All rights reserved. 37 * (c) UNIX System Laboratories, Inc. 38 * All or some portions of this file are derived from material licensed 39 * to the University of California by American Telephone and Telegraph 40 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 41 * the permission of UNIX System Laboratories, Inc. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. Neither the name of the University nor the names of its contributors 52 * may be used to endorse or promote products derived from this software 53 * without specific prior written permission. 54 * 55 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 56 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 57 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 58 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 59 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 60 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 61 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 62 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 63 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 64 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 65 * SUCH DAMAGE. 66 * 67 * @(#)ufs_disksubr.c 8.5 (Berkeley) 1/21/94 68 */ 69 70 #include <sys/cdefs.h> 71 __KERNEL_RCSID(0, "$NetBSD: subr_iostat.c,v 1.24 2018/09/03 16:29:35 riastradh Exp $"); 72 73 #include <sys/param.h> 74 #include <sys/kernel.h> 75 #include <sys/kmem.h> 76 #include <sys/iostat.h> 77 #include <sys/sysctl.h> 78 #include <sys/rwlock.h> 79 80 /* 81 * Function prototypes for sysctl nodes 82 */ 83 static int sysctl_hw_disknames(SYSCTLFN_PROTO); 84 static int sysctl_hw_iostatnames(SYSCTLFN_PROTO); 85 static int sysctl_hw_iostats(SYSCTLFN_PROTO); 86 87 static int 88 iostati_getnames(int disk_only, char *oldp, size_t *oldlenp, const void *newp, 89 u_int namelen); 90 91 /* 92 * A global list of all drives attached to the system. May grow or 93 * shrink over time. 94 */ 95 struct iostatlist_head iostatlist = TAILQ_HEAD_INITIALIZER(iostatlist); 96 int iostat_count; /* number of drives in global drivelist */ 97 krwlock_t iostatlist_lock; 98 99 static void sysctl_io_stats_setup(struct sysctllog **); 100 101 /* 102 * Initialise the iostat subsystem. 103 */ 104 void 105 iostat_init(void) 106 { 107 108 rw_init(&iostatlist_lock); 109 sysctl_io_stats_setup(NULL); 110 } 111 112 /* 113 * Searches the iostatlist for the iostat corresponding to the 114 * name provided. 115 */ 116 struct io_stats * 117 iostat_find(const char *name) 118 { 119 struct io_stats *iostatp; 120 121 KASSERT(name != NULL); 122 123 rw_enter(&iostatlist_lock, RW_READER); 124 TAILQ_FOREACH(iostatp, &iostatlist, io_link) { 125 if (strcmp(iostatp->io_name, name) == 0) { 126 break; 127 } 128 } 129 rw_exit(&iostatlist_lock); 130 131 return iostatp; 132 } 133 134 /* 135 * Allocate and initialise memory for the i/o statistics. 136 */ 137 struct io_stats * 138 iostat_alloc(int32_t type, void *parent, const char *name) 139 { 140 struct io_stats *stats; 141 142 stats = kmem_zalloc(sizeof(*stats), KM_SLEEP); 143 stats->io_type = type; 144 stats->io_parent = parent; 145 (void)strlcpy(stats->io_name, name, sizeof(stats->io_name)); 146 147 /* 148 * Set the attached timestamp. 149 */ 150 getmicrouptime(&stats->io_attachtime); 151 152 /* 153 * Link into the drivelist. 154 */ 155 rw_enter(&iostatlist_lock, RW_WRITER); 156 TAILQ_INSERT_TAIL(&iostatlist, stats, io_link); 157 iostat_count++; 158 rw_exit(&iostatlist_lock); 159 160 return stats; 161 } 162 163 /* 164 * Remove i/o from stats collection. 165 */ 166 void 167 iostat_free(struct io_stats *stats) 168 { 169 170 /* 171 * Remove from the iostat list. 172 */ 173 if (iostat_count == 0) 174 panic("iostat_free: iostat_count == 0"); 175 rw_enter(&iostatlist_lock, RW_WRITER); 176 TAILQ_REMOVE(&iostatlist, stats, io_link); 177 iostat_count--; 178 rw_exit(&iostatlist_lock); 179 kmem_free(stats, sizeof(*stats)); 180 } 181 182 /* 183 * multiply timeval by unsigned integer and add to result 184 */ 185 static void 186 timermac(struct timeval *a, uint64_t count, struct timeval *res) 187 { 188 struct timeval part = *a; 189 190 while (count) { 191 if (count & 1) 192 timeradd(res, &part, res); 193 timeradd(&part, &part, &part); 194 count >>= 1; 195 } 196 } 197 198 /* 199 * Increment the iostat wait counter. 200 * Accumulate wait time and timesum. 201 * 202 * Wait time is spent in the device bufq. 203 */ 204 void 205 iostat_wait(struct io_stats *stats) 206 { 207 struct timeval dv_time, diff_time; 208 int32_t count; 209 210 KASSERT(stats->io_wait >= 0); 211 212 getmicrouptime(&dv_time); 213 214 timersub(&dv_time, &stats->io_waitstamp, &diff_time); 215 count = stats->io_wait++; 216 if (count != 0) { 217 timermac(&diff_time, count, &stats->io_waitsum); 218 timeradd(&stats->io_waittime, &diff_time, &stats->io_waittime); 219 } 220 stats->io_waitstamp = dv_time; 221 } 222 223 /* 224 * Decrement the iostat wait counter. 225 * Increment the iostat busy counter. 226 * Accumulate wait and busy times and timesums. 227 * 228 * Busy time is spent being processed by the device. 229 * 230 * Old devices do not yet measure wait time, so skip 231 * processing it if the counter is still zero. 232 */ 233 void 234 iostat_busy(struct io_stats *stats) 235 { 236 struct timeval dv_time, diff_time; 237 int32_t count; 238 239 KASSERT(stats->io_wait >= 0); /* > 0 when iostat_wait is used */ 240 KASSERT(stats->io_busy >= 0); 241 242 getmicrouptime(&dv_time); 243 244 timersub(&dv_time, &stats->io_waitstamp, &diff_time); 245 if (stats->io_wait != 0) { 246 count = stats->io_wait--; 247 timermac(&diff_time, count, &stats->io_waitsum); 248 timeradd(&stats->io_waittime, &diff_time, &stats->io_waittime); 249 } 250 stats->io_waitstamp = dv_time; 251 252 timersub(&dv_time, &stats->io_busystamp, &diff_time); 253 count = stats->io_busy++; 254 if (count != 0) { 255 timermac(&diff_time, count, &stats->io_busysum); 256 timeradd(&stats->io_busytime, &diff_time, &stats->io_busytime); 257 } 258 stats->io_busystamp = dv_time; 259 } 260 261 /* 262 * Decrement the iostat busy counter, increment the byte count. 263 * Accumulate busy time and timesum. 264 */ 265 void 266 iostat_unbusy(struct io_stats *stats, long bcount, int read) 267 { 268 struct timeval dv_time, diff_time; 269 int32_t count; 270 271 KASSERT(stats->io_busy > 0); 272 273 getmicrouptime(&dv_time); 274 stats->io_timestamp = dv_time; 275 276 /* any op */ 277 timersub(&dv_time, &stats->io_busystamp, &diff_time); 278 count = stats->io_busy--; 279 timermac(&diff_time, count, &stats->io_busysum); 280 timeradd(&stats->io_busytime, &diff_time, &stats->io_busytime); 281 stats->io_busystamp = dv_time; 282 283 if (bcount > 0) { 284 if (read) { 285 stats->io_rbytes += bcount; 286 stats->io_rxfer++; 287 } else { 288 stats->io_wbytes += bcount; 289 stats->io_wxfer++; 290 } 291 } 292 } 293 294 /* 295 * Return non-zero if a device has an I/O request in flight. 296 */ 297 bool 298 iostat_isbusy(struct io_stats *stats) 299 { 300 301 return stats->io_busy != 0; 302 } 303 304 /* 305 * Increment the seek counter. This does look almost redundant but it 306 * abstracts the stats gathering. 307 */ 308 void 309 iostat_seek(struct io_stats *stats) 310 { 311 312 stats->io_seek++; 313 } 314 315 static int 316 sysctl_hw_disknames(SYSCTLFN_ARGS) 317 { 318 319 return iostati_getnames(1, oldp, oldlenp, newp, namelen); 320 } 321 322 static int 323 sysctl_hw_iostatnames(SYSCTLFN_ARGS) 324 { 325 326 return iostati_getnames(0, oldp, oldlenp, newp, namelen); 327 } 328 329 static int 330 iostati_getnames(int disk_only, char *oldp, size_t *oldlenp, const void *newp, 331 u_int namelen) 332 { 333 char bf[IOSTATNAMELEN + 1]; 334 char *where = oldp; 335 struct io_stats *stats; 336 size_t needed, left, slen; 337 int error, first; 338 339 if (newp != NULL) 340 return (EPERM); 341 if (namelen != 0) 342 return (EINVAL); 343 344 first = 1; 345 error = 0; 346 needed = 0; 347 left = *oldlenp; 348 349 rw_enter(&iostatlist_lock, RW_READER); 350 for (stats = TAILQ_FIRST(&iostatlist); stats != NULL; 351 stats = TAILQ_NEXT(stats, io_link)) { 352 if ((disk_only == 1) && (stats->io_type != IOSTAT_DISK)) 353 continue; 354 355 if (where == NULL) 356 needed += strlen(stats->io_name) + 1; 357 else { 358 memset(bf, 0, sizeof(bf)); 359 if (first) { 360 strncpy(bf, stats->io_name, sizeof(bf)); 361 first = 0; 362 } else { 363 bf[0] = ' '; 364 strncpy(bf + 1, stats->io_name, 365 sizeof(bf) - 1); 366 } 367 bf[IOSTATNAMELEN] = '\0'; 368 slen = strlen(bf); 369 if (left < slen + 1) 370 break; 371 /* +1 to copy out the trailing NUL byte */ 372 error = copyout(bf, where, slen + 1); 373 if (error) 374 break; 375 where += slen; 376 needed += slen; 377 left -= slen; 378 } 379 } 380 rw_exit(&iostatlist_lock); 381 *oldlenp = needed; 382 return (error); 383 } 384 385 static int 386 sysctl_hw_iostats(SYSCTLFN_ARGS) 387 { 388 struct io_sysctl sdrive; 389 struct io_stats *stats; 390 char *where = oldp; 391 size_t tocopy, left; 392 int error; 393 394 if (newp != NULL) 395 return (EPERM); 396 397 /* 398 * The original hw.diskstats call was broken and did not require 399 * the userland to pass in its size of struct disk_sysctl. This 400 * was fixed after NetBSD 1.6 was released. 401 */ 402 if (namelen == 0) 403 tocopy = offsetof(struct io_sysctl, busy); 404 else 405 tocopy = name[0]; 406 407 if (where == NULL) { 408 *oldlenp = iostat_count * tocopy; 409 return (0); 410 } 411 412 error = 0; 413 left = *oldlenp; 414 memset(&sdrive, 0, sizeof(sdrive)); 415 *oldlenp = 0; 416 417 rw_enter(&iostatlist_lock, RW_READER); 418 TAILQ_FOREACH(stats, &iostatlist, io_link) { 419 if (left < tocopy) 420 break; 421 422 strncpy(sdrive.name, stats->io_name, sizeof(sdrive.name)); 423 sdrive.attachtime_sec = stats->io_attachtime.tv_sec; 424 sdrive.attachtime_usec = stats->io_attachtime.tv_usec; 425 sdrive.timestamp_sec = stats->io_busystamp.tv_sec; 426 sdrive.timestamp_usec = stats->io_busystamp.tv_usec; 427 428 sdrive.time_sec = stats->io_busytime.tv_sec; 429 sdrive.time_usec = stats->io_busytime.tv_usec; 430 431 sdrive.seek = stats->io_seek; 432 433 sdrive.rxfer = stats->io_rxfer; 434 sdrive.wxfer = stats->io_wxfer; 435 sdrive.xfer = stats->io_rxfer + stats->io_wxfer; 436 437 sdrive.rbytes = stats->io_rbytes; 438 sdrive.wbytes = stats->io_wbytes; 439 sdrive.bytes = stats->io_rbytes + stats->io_wbytes; 440 441 sdrive.wait_sec = stats->io_waittime.tv_sec; 442 sdrive.wait_usec = stats->io_waittime.tv_usec; 443 444 sdrive.time_sec = stats->io_busytime.tv_sec; 445 sdrive.time_usec = stats->io_busytime.tv_usec; 446 447 sdrive.waitsum_sec = stats->io_waitsum.tv_sec; 448 sdrive.waitsum_usec = stats->io_waitsum.tv_usec; 449 450 sdrive.busysum_sec = stats->io_busysum.tv_sec; 451 sdrive.busysum_usec = stats->io_busysum.tv_usec; 452 453 sdrive.busy = stats->io_busy; 454 455 error = copyout(&sdrive, where, uimin(tocopy, sizeof(sdrive))); 456 if (error) 457 break; 458 where += tocopy; 459 *oldlenp += tocopy; 460 left -= tocopy; 461 } 462 rw_exit(&iostatlist_lock); 463 return (error); 464 } 465 466 static void 467 sysctl_io_stats_setup(struct sysctllog **clog) 468 { 469 470 sysctl_createv(clog, 0, NULL, NULL, 471 CTLFLAG_PERMANENT, 472 CTLTYPE_STRING, "disknames", 473 SYSCTL_DESCR("List of disk drives present"), 474 sysctl_hw_disknames, 0, NULL, 0, 475 CTL_HW, HW_DISKNAMES, CTL_EOL); 476 sysctl_createv(clog, 0, NULL, NULL, 477 CTLFLAG_PERMANENT, 478 CTLTYPE_STRING, "iostatnames", 479 SYSCTL_DESCR("I/O stats are being collected for these" 480 " devices"), 481 sysctl_hw_iostatnames, 0, NULL, 0, 482 CTL_HW, HW_IOSTATNAMES, CTL_EOL); 483 sysctl_createv(clog, 0, NULL, NULL, 484 CTLFLAG_PERMANENT, 485 CTLTYPE_STRUCT, "iostats", 486 SYSCTL_DESCR("Statistics on device I/O operations"), 487 sysctl_hw_iostats, 0, NULL, 0, 488 CTL_HW, HW_IOSTATS, CTL_EOL); 489 } 490