subr_iostat.c revision 1.21
1 /* $NetBSD: subr_iostat.c,v 1.21 2014/10/18 08:33:29 snj 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 1.21 2014/10/18 08:33:29 snj 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 * Increment a iostat busy counter. If the counter is going from 187 * 0 to 1, set the timestamp. 188 */ 189 void 190 iostat_busy(struct io_stats *stats) 191 { 192 193 if (stats->io_busy++ == 0) 194 getmicrouptime(&stats->io_timestamp); 195 } 196 197 /* 198 * Decrement a iostat busy counter, increment the byte count, total busy 199 * time, and reset the timestamp. 200 */ 201 void 202 iostat_unbusy(struct io_stats *stats, long bcount, int read) 203 { 204 struct timeval dv_time, diff_time; 205 206 if (stats->io_busy-- == 0) { 207 printf("%s: busy < 0\n", stats->io_name); 208 panic("iostat_unbusy"); 209 } 210 211 getmicrouptime(&dv_time); 212 213 timersub(&dv_time, &stats->io_timestamp, &diff_time); 214 timeradd(&stats->io_time, &diff_time, &stats->io_time); 215 216 stats->io_timestamp = dv_time; 217 if (bcount > 0) { 218 if (read) { 219 stats->io_rbytes += bcount; 220 stats->io_rxfer++; 221 } else { 222 stats->io_wbytes += bcount; 223 stats->io_wxfer++; 224 } 225 } 226 } 227 228 /* 229 * Return non-zero if a device has an I/O request in flight. 230 */ 231 bool 232 iostat_isbusy(struct io_stats *stats) 233 { 234 235 return stats->io_busy != 0; 236 } 237 238 /* 239 * Increment the seek counter. This does look almost redundant but it 240 * abstracts the stats gathering. 241 */ 242 void 243 iostat_seek(struct io_stats *stats) 244 { 245 246 stats->io_seek++; 247 } 248 249 static int 250 sysctl_hw_disknames(SYSCTLFN_ARGS) 251 { 252 253 return iostati_getnames(1, oldp, oldlenp, newp, namelen); 254 } 255 256 static int 257 sysctl_hw_iostatnames(SYSCTLFN_ARGS) 258 { 259 260 return iostati_getnames(0, oldp, oldlenp, newp, namelen); 261 } 262 263 static int 264 iostati_getnames(int disk_only, char *oldp, size_t *oldlenp, const void *newp, 265 u_int namelen) 266 { 267 char bf[IOSTATNAMELEN + 1]; 268 char *where = oldp; 269 struct io_stats *stats; 270 size_t needed, left, slen; 271 int error, first; 272 273 if (newp != NULL) 274 return (EPERM); 275 if (namelen != 0) 276 return (EINVAL); 277 278 first = 1; 279 error = 0; 280 needed = 0; 281 left = *oldlenp; 282 283 rw_enter(&iostatlist_lock, RW_READER); 284 for (stats = TAILQ_FIRST(&iostatlist); stats != NULL; 285 stats = TAILQ_NEXT(stats, io_link)) { 286 if ((disk_only == 1) && (stats->io_type != IOSTAT_DISK)) 287 continue; 288 289 if (where == NULL) 290 needed += strlen(stats->io_name) + 1; 291 else { 292 memset(bf, 0, sizeof(bf)); 293 if (first) { 294 strncpy(bf, stats->io_name, sizeof(bf)); 295 first = 0; 296 } else { 297 bf[0] = ' '; 298 strncpy(bf + 1, stats->io_name, 299 sizeof(bf) - 1); 300 } 301 bf[IOSTATNAMELEN] = '\0'; 302 slen = strlen(bf); 303 if (left < slen + 1) 304 break; 305 /* +1 to copy out the trailing NUL byte */ 306 error = copyout(bf, where, slen + 1); 307 if (error) 308 break; 309 where += slen; 310 needed += slen; 311 left -= slen; 312 } 313 } 314 rw_exit(&iostatlist_lock); 315 *oldlenp = needed; 316 return (error); 317 } 318 319 static int 320 sysctl_hw_iostats(SYSCTLFN_ARGS) 321 { 322 struct io_sysctl sdrive; 323 struct io_stats *stats; 324 char *where = oldp; 325 size_t tocopy, left; 326 int error; 327 328 if (newp != NULL) 329 return (EPERM); 330 331 /* 332 * The original hw.diskstats call was broken and did not require 333 * the userland to pass in its size of struct disk_sysctl. This 334 * was fixed after NetBSD 1.6 was released. 335 */ 336 if (namelen == 0) 337 tocopy = offsetof(struct io_sysctl, busy); 338 else 339 tocopy = name[0]; 340 341 if (where == NULL) { 342 *oldlenp = iostat_count * tocopy; 343 return (0); 344 } 345 346 error = 0; 347 left = *oldlenp; 348 memset(&sdrive, 0, sizeof(sdrive)); 349 *oldlenp = 0; 350 351 rw_enter(&iostatlist_lock, RW_READER); 352 TAILQ_FOREACH(stats, &iostatlist, io_link) { 353 if (left < tocopy) 354 break; 355 strncpy(sdrive.name, stats->io_name, sizeof(sdrive.name)); 356 sdrive.xfer = stats->io_rxfer + stats->io_wxfer; 357 sdrive.rxfer = stats->io_rxfer; 358 sdrive.wxfer = stats->io_wxfer; 359 sdrive.seek = stats->io_seek; 360 sdrive.bytes = stats->io_rbytes + stats->io_wbytes; 361 sdrive.rbytes = stats->io_rbytes; 362 sdrive.wbytes = stats->io_wbytes; 363 sdrive.attachtime_sec = stats->io_attachtime.tv_sec; 364 sdrive.attachtime_usec = stats->io_attachtime.tv_usec; 365 sdrive.timestamp_sec = stats->io_timestamp.tv_sec; 366 sdrive.timestamp_usec = stats->io_timestamp.tv_usec; 367 sdrive.time_sec = stats->io_time.tv_sec; 368 sdrive.time_usec = stats->io_time.tv_usec; 369 sdrive.busy = stats->io_busy; 370 371 error = copyout(&sdrive, where, min(tocopy, sizeof(sdrive))); 372 if (error) 373 break; 374 where += tocopy; 375 *oldlenp += tocopy; 376 left -= tocopy; 377 } 378 rw_exit(&iostatlist_lock); 379 return (error); 380 } 381 382 static void 383 sysctl_io_stats_setup(struct sysctllog **clog) 384 { 385 386 sysctl_createv(clog, 0, NULL, NULL, 387 CTLFLAG_PERMANENT, 388 CTLTYPE_STRING, "disknames", 389 SYSCTL_DESCR("List of disk drives present"), 390 sysctl_hw_disknames, 0, NULL, 0, 391 CTL_HW, HW_DISKNAMES, CTL_EOL); 392 sysctl_createv(clog, 0, NULL, NULL, 393 CTLFLAG_PERMANENT, 394 CTLTYPE_STRING, "iostatnames", 395 SYSCTL_DESCR("I/O stats are being collected for these" 396 " devices"), 397 sysctl_hw_iostatnames, 0, NULL, 0, 398 CTL_HW, HW_IOSTATNAMES, CTL_EOL); 399 sysctl_createv(clog, 0, NULL, NULL, 400 CTLFLAG_PERMANENT, 401 CTLTYPE_STRUCT, "iostats", 402 SYSCTL_DESCR("Statistics on device I/O operations"), 403 sysctl_hw_iostats, 0, NULL, 0, 404 CTL_HW, HW_IOSTATS, CTL_EOL); 405 } 406
Indexes created Tue Sep 23 02:09:52 GMT 2025