1 /* $NetBSD: subr_iostat.c,v 1.22 2017/03/05 23:07:12 mlelstv 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 1.22 2017/03/05 23:07:12 mlelstv 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 if (stats == NULL) 144 panic("iostat_alloc: cannot allocate memory for stats buffer"); 145 146 stats->io_type = type; 147 stats->io_parent = parent; 148 (void)strlcpy(stats->io_name, name, sizeof(stats->io_name)); 149 150 /* 151 * Set the attached timestamp. 152 */ 153 getmicrouptime(&stats->io_attachtime); 154 155 /* 156 * Link into the drivelist. 157 */ 158 rw_enter(&iostatlist_lock, RW_WRITER); 159 TAILQ_INSERT_TAIL(&iostatlist, stats, io_link); 160 iostat_count++; 161 rw_exit(&iostatlist_lock); 162 163 return stats; 164 } 165 166 /* 167 * Remove i/o from stats collection. 168 */ 169 void 170 iostat_free(struct io_stats *stats) 171 { 172 173 /* 174 * Remove from the iostat list. 175 */ 176 if (iostat_count == 0) 177 panic("iostat_free: iostat_count == 0"); 178 rw_enter(&iostatlist_lock, RW_WRITER); 179 TAILQ_REMOVE(&iostatlist, stats, io_link); 180 iostat_count--; 181 rw_exit(&iostatlist_lock); 182 kmem_free(stats, sizeof(*stats)); 183 } 184 185 /* 186 * multiply timeval by unsigned integer and add to result 187 */ 188 static void 189 timermac(struct timeval *a, uint64_t count, struct timeval *res) 190 { 191 struct timeval part = *a; 192 193 while (count) { 194 if (count & 1) 195 timeradd(res, &part, res); 196 timeradd(&part, &part, &part); 197 count >>= 1; 198 } 199 } 200 201 /* 202 * Increment the iostat wait counter. 203 * Accumulate wait time and timesum. 204 * 205 * Wait time is spent in the device bufq. 206 */ 207 void 208 iostat_wait(struct io_stats *stats) 209 { 210 struct timeval dv_time, diff_time; 211 int32_t count; 212 213 KASSERT(stats->io_wait >= 0); 214 215 getmicrouptime(&dv_time); 216 217 timersub(&dv_time, &stats->io_waitstamp, &diff_time); 218 count = stats->io_wait++; 219 if (count != 0) { 220 timermac(&diff_time, count, &stats->io_waitsum); 221 timeradd(&stats->io_waittime, &diff_time, &stats->io_waittime); 222 } 223 stats->io_waitstamp = dv_time; 224 } 225 226 /* 227 * Decrement the iostat wait counter. 228 * Increment the iostat busy counter. 229 * Accumulate wait and busy times and timesums. 230 * 231 * Busy time is spent being processed by the device. 232 * 233 * Old devices do not yet measure wait time, so skip 234 * processing it if the counter is still zero. 235 */ 236 void 237 iostat_busy(struct io_stats *stats) 238 { 239 struct timeval dv_time, diff_time; 240 int32_t count; 241 242 KASSERT(stats->io_wait >= 0); /* > 0 when iostat_wait is used */ 243 KASSERT(stats->io_busy >= 0); 244 245 getmicrouptime(&dv_time); 246 247 timersub(&dv_time, &stats->io_waitstamp, &diff_time); 248 if (stats->io_wait != 0) { 249 count = stats->io_wait--; 250 timermac(&diff_time, count, &stats->io_waitsum); 251 timeradd(&stats->io_waittime, &diff_time, &stats->io_waittime); 252 } 253 stats->io_waitstamp = dv_time; 254 255 timersub(&dv_time, &stats->io_busystamp, &diff_time); 256 count = stats->io_busy++; 257 if (count != 0) { 258 timermac(&diff_time, count, &stats->io_busysum); 259 timeradd(&stats->io_busytime, &diff_time, &stats->io_busytime); 260 } 261 stats->io_busystamp = dv_time; 262 } 263 264 /* 265 * Decrement the iostat busy counter, increment the byte count. 266 * Accumulate busy time and timesum. 267 */ 268 void 269 iostat_unbusy(struct io_stats *stats, long bcount, int read) 270 { 271 struct timeval dv_time, diff_time; 272 int32_t count; 273 274 KASSERT(stats->io_busy > 0); 275 276 getmicrouptime(&dv_time); 277 stats->io_timestamp = dv_time; 278 279 /* any op */ 280 timersub(&dv_time, &stats->io_busystamp, &diff_time); 281 count = stats->io_busy--; 282 timermac(&diff_time, count, &stats->io_busysum); 283 timeradd(&stats->io_busytime, &diff_time, &stats->io_busytime); 284 stats->io_busystamp = dv_time; 285 286 if (bcount > 0) { 287 if (read) { 288 stats->io_rbytes += bcount; 289 stats->io_rxfer++; 290 } else { 291 stats->io_wbytes += bcount; 292 stats->io_wxfer++; 293 } 294 } 295 } 296 297 /* 298 * Return non-zero if a device has an I/O request in flight. 299 */ 300 bool 301 iostat_isbusy(struct io_stats *stats) 302 { 303 304 return stats->io_busy != 0; 305 } 306 307 /* 308 * Increment the seek counter. This does look almost redundant but it 309 * abstracts the stats gathering. 310 */ 311 void 312 iostat_seek(struct io_stats *stats) 313 { 314 315 stats->io_seek++; 316 } 317 318 static int 319 sysctl_hw_disknames(SYSCTLFN_ARGS) 320 { 321 322 return iostati_getnames(1, oldp, oldlenp, newp, namelen); 323 } 324 325 static int 326 sysctl_hw_iostatnames(SYSCTLFN_ARGS) 327 { 328 329 return iostati_getnames(0, oldp, oldlenp, newp, namelen); 330 } 331 332 static int 333 iostati_getnames(int disk_only, char *oldp, size_t *oldlenp, const void *newp, 334 u_int namelen) 335 { 336 char bf[IOSTATNAMELEN + 1]; 337 char *where = oldp; 338 struct io_stats *stats; 339 size_t needed, left, slen; 340 int error, first; 341 342 if (newp != NULL) 343 return (EPERM); 344 if (namelen != 0) 345 return (EINVAL); 346 347 first = 1; 348 error = 0; 349 needed = 0; 350 left = *oldlenp; 351 352 rw_enter(&iostatlist_lock, RW_READER); 353 for (stats = TAILQ_FIRST(&iostatlist); stats != NULL; 354 stats = TAILQ_NEXT(stats, io_link)) { 355 if ((disk_only == 1) && (stats->io_type != IOSTAT_DISK)) 356 continue; 357 358 if (where == NULL) 359 needed += strlen(stats->io_name) + 1; 360 else { 361 memset(bf, 0, sizeof(bf)); 362 if (first) { 363 strncpy(bf, stats->io_name, sizeof(bf)); 364 first = 0; 365 } else { 366 bf[0] = ' '; 367 strncpy(bf + 1, stats->io_name, 368 sizeof(bf) - 1); 369 } 370 bf[IOSTATNAMELEN] = '\0'; 371 slen = strlen(bf); 372 if (left < slen + 1) 373 break; 374 /* +1 to copy out the trailing NUL byte */ 375 error = copyout(bf, where, slen + 1); 376 if (error) 377 break; 378 where += slen; 379 needed += slen; 380 left -= slen; 381 } 382 } 383 rw_exit(&iostatlist_lock); 384 *oldlenp = needed; 385 return (error); 386 } 387 388 static int 389 sysctl_hw_iostats(SYSCTLFN_ARGS) 390 { 391 struct io_sysctl sdrive; 392 struct io_stats *stats; 393 char *where = oldp; 394 size_t tocopy, left; 395 int error; 396 397 if (newp != NULL) 398 return (EPERM); 399 400 /* 401 * The original hw.diskstats call was broken and did not require 402 * the userland to pass in its size of struct disk_sysctl. This 403 * was fixed after NetBSD 1.6 was released. 404 */ 405 if (namelen == 0) 406 tocopy = offsetof(struct io_sysctl, busy); 407 else 408 tocopy = name[0]; 409 410 if (where == NULL) { 411 *oldlenp = iostat_count * tocopy; 412 return (0); 413 } 414 415 error = 0; 416 left = *oldlenp; 417 memset(&sdrive, 0, sizeof(sdrive)); 418 *oldlenp = 0; 419 420 rw_enter(&iostatlist_lock, RW_READER); 421 TAILQ_FOREACH(stats, &iostatlist, io_link) { 422 if (left < tocopy) 423 break; 424 425 strncpy(sdrive.name, stats->io_name, sizeof(sdrive.name)); 426 sdrive.attachtime_sec = stats->io_attachtime.tv_sec; 427 sdrive.attachtime_usec = stats->io_attachtime.tv_usec; 428 sdrive.timestamp_sec = stats->io_busystamp.tv_sec; 429 sdrive.timestamp_usec = stats->io_busystamp.tv_usec; 430 431 sdrive.time_sec = stats->io_busytime.tv_sec; 432 sdrive.time_usec = stats->io_busytime.tv_usec; 433 434 sdrive.seek = stats->io_seek; 435 436 sdrive.rxfer = stats->io_rxfer; 437 sdrive.wxfer = stats->io_wxfer; 438 sdrive.xfer = stats->io_rxfer + stats->io_wxfer; 439 440 sdrive.rbytes = stats->io_rbytes; 441 sdrive.wbytes = stats->io_wbytes; 442 sdrive.bytes = stats->io_rbytes + stats->io_wbytes; 443 444 sdrive.wait_sec = stats->io_waittime.tv_sec; 445 sdrive.wait_usec = stats->io_waittime.tv_usec; 446 447 sdrive.time_sec = stats->io_busytime.tv_sec; 448 sdrive.time_usec = stats->io_busytime.tv_usec; 449 450 sdrive.waitsum_sec = stats->io_waitsum.tv_sec; 451 sdrive.waitsum_usec = stats->io_waitsum.tv_usec; 452 453 sdrive.busysum_sec = stats->io_busysum.tv_sec; 454 sdrive.busysum_usec = stats->io_busysum.tv_usec; 455 456 sdrive.busy = stats->io_busy; 457 458 error = copyout(&sdrive, where, min(tocopy, sizeof(sdrive))); 459 if (error) 460 break; 461 where += tocopy; 462 *oldlenp += tocopy; 463 left -= tocopy; 464 } 465 rw_exit(&iostatlist_lock); 466 return (error); 467 } 468 469 static void 470 sysctl_io_stats_setup(struct sysctllog **clog) 471 { 472 473 sysctl_createv(clog, 0, NULL, NULL, 474 CTLFLAG_PERMANENT, 475 CTLTYPE_STRING, "disknames", 476 SYSCTL_DESCR("List of disk drives present"), 477 sysctl_hw_disknames, 0, NULL, 0, 478 CTL_HW, HW_DISKNAMES, CTL_EOL); 479 sysctl_createv(clog, 0, NULL, NULL, 480 CTLFLAG_PERMANENT, 481 CTLTYPE_STRING, "iostatnames", 482 SYSCTL_DESCR("I/O stats are being collected for these" 483 " devices"), 484 sysctl_hw_iostatnames, 0, NULL, 0, 485 CTL_HW, HW_IOSTATNAMES, CTL_EOL); 486 sysctl_createv(clog, 0, NULL, NULL, 487 CTLFLAG_PERMANENT, 488 CTLTYPE_STRUCT, "iostats", 489 SYSCTL_DESCR("Statistics on device I/O operations"), 490 sysctl_hw_iostats, 0, NULL, 0, 491 CTL_HW, HW_IOSTATS, CTL_EOL); 492 } 493