subr_iostat.c revision 1.17
1 /* $NetBSD: subr_iostat.c,v 1.17 2009/04/04 07:30:10 ad 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 1.17 2009/04/04 07:30:10 ad 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 /* 100 * Initialise the iostat subsystem. 101 */ 102 void 103 iostat_init(void) 104 { 105 106 rw_init(&iostatlist_lock); 107 } 108 109 /* 110 * Searches the iostatlist for the iostat corresponding to the 111 * name provided. 112 */ 113 struct io_stats * 114 iostat_find(const char *name) 115 { 116 struct io_stats *iostatp; 117 118 KASSERT(name != NULL); 119 120 rw_enter(&iostatlist_lock, RW_READER); 121 TAILQ_FOREACH(iostatp, &iostatlist, io_link) { 122 if (strcmp(iostatp->io_name, name) == 0) { 123 break; 124 } 125 } 126 rw_exit(&iostatlist_lock); 127 128 return iostatp; 129 } 130 131 /* 132 * Allocate and initialise memory for the i/o statistics. 133 */ 134 struct io_stats * 135 iostat_alloc(int32_t type, void *parent, const char *name) 136 { 137 struct io_stats *stats; 138 139 stats = kmem_zalloc(sizeof(*stats), KM_SLEEP); 140 if (stats == NULL) 141 panic("iostat_alloc: cannot allocate memory for stats buffer"); 142 143 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 * Increment a iostat busy counter. If the counter is going from 184 * 0 to 1, set the timestamp. 185 */ 186 void 187 iostat_busy(struct io_stats *stats) 188 { 189 190 if (stats->io_busy++ == 0) 191 getmicrouptime(&stats->io_timestamp); 192 } 193 194 /* 195 * Decrement a iostat busy counter, increment the byte count, total busy 196 * time, and reset the timestamp. 197 */ 198 void 199 iostat_unbusy(struct io_stats *stats, long bcount, int read) 200 { 201 struct timeval dv_time, diff_time; 202 203 if (stats->io_busy-- == 0) { 204 printf("%s: busy < 0\n", stats->io_name); 205 panic("iostat_unbusy"); 206 } 207 208 getmicrouptime(&dv_time); 209 210 timersub(&dv_time, &stats->io_timestamp, &diff_time); 211 timeradd(&stats->io_time, &diff_time, &stats->io_time); 212 213 stats->io_timestamp = dv_time; 214 if (bcount > 0) { 215 if (read) { 216 stats->io_rbytes += bcount; 217 stats->io_rxfer++; 218 } else { 219 stats->io_wbytes += bcount; 220 stats->io_wxfer++; 221 } 222 } 223 } 224 225 /* 226 * Return non-zero if a device has an I/O request in flight. 227 */ 228 bool 229 iostat_isbusy(struct io_stats *stats) 230 { 231 232 return stats->io_busy != 0; 233 } 234 235 /* 236 * Increment the seek counter. This does look almost redundant but it 237 * abstracts the stats gathering. 238 */ 239 void 240 iostat_seek(struct io_stats *stats) 241 { 242 243 stats->io_seek++; 244 } 245 246 static int 247 sysctl_hw_disknames(SYSCTLFN_ARGS) 248 { 249 250 return iostati_getnames(1, oldp, oldlenp, newp, namelen); 251 } 252 253 static int 254 sysctl_hw_iostatnames(SYSCTLFN_ARGS) 255 { 256 257 return iostati_getnames(0, oldp, oldlenp, newp, namelen); 258 } 259 260 static int 261 iostati_getnames(int disk_only, char *oldp, size_t *oldlenp, const void *newp, 262 u_int namelen) 263 { 264 char bf[IOSTATNAMELEN + 1]; 265 char *where = oldp; 266 struct io_stats *stats; 267 size_t needed, left, slen; 268 int error, first; 269 270 if (newp != NULL) 271 return (EPERM); 272 if (namelen != 0) 273 return (EINVAL); 274 275 first = 1; 276 error = 0; 277 needed = 0; 278 left = *oldlenp; 279 280 rw_enter(&iostatlist_lock, RW_READER); 281 for (stats = TAILQ_FIRST(&iostatlist); stats != NULL; 282 stats = TAILQ_NEXT(stats, io_link)) { 283 if ((disk_only == 1) && (stats->io_type != IOSTAT_DISK)) 284 continue; 285 286 if (where == NULL) 287 needed += strlen(stats->io_name) + 1; 288 else { 289 memset(bf, 0, sizeof(bf)); 290 if (first) { 291 strncpy(bf, stats->io_name, sizeof(bf)); 292 first = 0; 293 } else { 294 bf[0] = ' '; 295 strncpy(bf + 1, stats->io_name, 296 sizeof(bf) - 1); 297 } 298 bf[IOSTATNAMELEN] = '\0'; 299 slen = strlen(bf); 300 if (left < slen + 1) 301 break; 302 /* +1 to copy out the trailing NUL byte */ 303 error = copyout(bf, where, slen + 1); 304 if (error) 305 break; 306 where += slen; 307 needed += slen; 308 left -= slen; 309 } 310 } 311 rw_exit(&iostatlist_lock); 312 *oldlenp = needed; 313 return (error); 314 } 315 316 static int 317 sysctl_hw_iostats(SYSCTLFN_ARGS) 318 { 319 struct io_sysctl sdrive; 320 struct io_stats *stats; 321 char *where = oldp; 322 size_t tocopy, left; 323 int error; 324 325 if (newp != NULL) 326 return (EPERM); 327 328 /* 329 * The original hw.diskstats call was broken and did not require 330 * the userland to pass in it's size of struct disk_sysctl. This 331 * was fixed after NetBSD 1.6 was released. 332 */ 333 if (namelen == 0) 334 tocopy = offsetof(struct io_sysctl, busy); 335 else 336 tocopy = name[0]; 337 338 if (where == NULL) { 339 *oldlenp = iostat_count * tocopy; 340 return (0); 341 } 342 343 error = 0; 344 left = *oldlenp; 345 memset(&sdrive, 0, sizeof(sdrive)); 346 *oldlenp = 0; 347 348 rw_enter(&iostatlist_lock, RW_READER); 349 TAILQ_FOREACH(stats, &iostatlist, io_link) { 350 if (left < tocopy) 351 break; 352 strncpy(sdrive.name, stats->io_name, sizeof(sdrive.name)); 353 sdrive.xfer = stats->io_rxfer + stats->io_wxfer; 354 sdrive.rxfer = stats->io_rxfer; 355 sdrive.wxfer = stats->io_wxfer; 356 sdrive.seek = stats->io_seek; 357 sdrive.bytes = stats->io_rbytes + stats->io_wbytes; 358 sdrive.rbytes = stats->io_rbytes; 359 sdrive.wbytes = stats->io_wbytes; 360 sdrive.attachtime_sec = stats->io_attachtime.tv_sec; 361 sdrive.attachtime_usec = stats->io_attachtime.tv_usec; 362 sdrive.timestamp_sec = stats->io_timestamp.tv_sec; 363 sdrive.timestamp_usec = stats->io_timestamp.tv_usec; 364 sdrive.time_sec = stats->io_time.tv_sec; 365 sdrive.time_usec = stats->io_time.tv_usec; 366 sdrive.busy = stats->io_busy; 367 368 error = copyout(&sdrive, where, min(tocopy, sizeof(sdrive))); 369 if (error) 370 break; 371 where += tocopy; 372 *oldlenp += tocopy; 373 left -= tocopy; 374 } 375 rw_exit(&iostatlist_lock); 376 return (error); 377 } 378 379 SYSCTL_SETUP(sysctl_io_stats_setup, "sysctl i/o stats setup") 380 { 381 382 sysctl_createv(clog, 0, NULL, NULL, 383 CTLFLAG_PERMANENT, 384 CTLTYPE_STRING, "disknames", 385 SYSCTL_DESCR("List of disk drives present"), 386 sysctl_hw_disknames, 0, NULL, 0, 387 CTL_HW, HW_DISKNAMES, CTL_EOL); 388 sysctl_createv(clog, 0, NULL, NULL, 389 CTLFLAG_PERMANENT, 390 CTLTYPE_STRING, "iostatnames", 391 SYSCTL_DESCR("I/O stats are being collected for these" 392 " devices"), 393 sysctl_hw_iostatnames, 0, NULL, 0, 394 CTL_HW, HW_IOSTATNAMES, CTL_EOL); 395 sysctl_createv(clog, 0, NULL, NULL, 396 CTLFLAG_PERMANENT, 397 CTLTYPE_STRUCT, "iostats", 398 SYSCTL_DESCR("Statistics on device I/O operations"), 399 sysctl_hw_iostats, 0, NULL, 0, 400 CTL_HW, HW_IOSTATS, CTL_EOL); 401 } 402
Indexes created Mon Sep 22 13:09:51 GMT 2025