1 /* 2 * Copyright (c) 1997, 1998, 1999 Kenneth D. Merry. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * $Id: subr_devstat.c,v 1.10 1999/04/11 02:27:06 eivind Exp $ 29 */ 30 31 #include <sys/param.h> 32 #include <sys/kernel.h> 33 #include <sys/systm.h> 34 #include <sys/time.h> 35 #include <sys/types.h> 36 #include <sys/sysctl.h> 37 38 #include <sys/devicestat.h> 39 40 static int devstat_num_devs; 41 static long devstat_generation; 42 static int devstat_version = DEVSTAT_VERSION; 43 static int devstat_current_devnumber; 44 45 static STAILQ_HEAD(devstatlist, devstat) device_statq; 46 47 /* 48 * Take a malloced and zeroed devstat structure given to us, fill it in 49 * and add it to the queue of devices. 50 */ 51 void 52 devstat_add_entry(struct devstat *ds, const char *dev_name, 53 int unit_number, u_int32_t block_size, 54 devstat_support_flags flags, 55 devstat_type_flags device_type, 56 devstat_priority priority) 57 { 58 int s; 59 struct devstatlist *devstat_head; 60 struct devstat *ds_tmp; 61 62 if (ds == NULL) 63 return; 64 65 if (devstat_num_devs == 0) 66 STAILQ_INIT(&device_statq); 67 68 devstat_generation++; 69 devstat_num_devs++; 70 71 devstat_head = &device_statq; 72 73 /* 74 * Priority sort. Each driver passes in its priority when it adds 75 * its devstat entry. Drivers are sorted first by priority, and 76 * then by probe order. 77 * 78 * For the first device, we just insert it, since the priority 79 * doesn't really matter yet. Subsequent devices are inserted into 80 * the list using the order outlined above. 81 */ 82 if (devstat_num_devs == 1) 83 STAILQ_INSERT_TAIL(devstat_head, ds, dev_links); 84 else { 85 for (ds_tmp = STAILQ_FIRST(devstat_head); ds_tmp != NULL; 86 ds_tmp = STAILQ_NEXT(ds_tmp, dev_links)) { 87 struct devstat *ds_next; 88 89 ds_next = STAILQ_NEXT(ds_tmp, dev_links); 90 91 /* 92 * If we find a break between higher and lower 93 * priority items, and if this item fits in the 94 * break, insert it. This also applies if the 95 * "lower priority item" is the end of the list. 96 */ 97 if ((priority <= ds_tmp->priority) 98 && ((ds_next == NULL) 99 || (priority > ds_next->priority))) { 100 STAILQ_INSERT_AFTER(devstat_head, ds_tmp, ds, 101 dev_links); 102 break; 103 } else if (priority > ds_tmp->priority) { 104 /* 105 * If this is the case, we should be able 106 * to insert ourselves at the head of the 107 * list. If we can't, something is wrong. 108 */ 109 if (ds_tmp == STAILQ_FIRST(devstat_head)) { 110 STAILQ_INSERT_HEAD(devstat_head, 111 ds, dev_links); 112 break; 113 } else { 114 STAILQ_INSERT_TAIL(devstat_head, 115 ds, dev_links); 116 printf("devstat_add_entry: HELP! " 117 "sorting problem detected " 118 "for %s%d\n", dev_name, 119 unit_number); 120 break; 121 } 122 } 123 } 124 } 125 126 ds->device_number = devstat_current_devnumber++; 127 ds->unit_number = unit_number; 128 strncpy(ds->device_name, dev_name, DEVSTAT_NAME_LEN); 129 ds->device_name[DEVSTAT_NAME_LEN - 1] = '\0'; 130 ds->block_size = block_size; 131 ds->flags = flags; 132 ds->device_type = device_type; 133 ds->priority = priority; 134 135 s = splclock(); 136 getmicrotime(&ds->dev_creation_time); 137 splx(s); 138 } 139 140 /* 141 * Remove a devstat structure from the list of devices. 142 */ 143 void 144 devstat_remove_entry(struct devstat *ds) 145 { 146 struct devstatlist *devstat_head; 147 148 if (ds == NULL) 149 return; 150 151 devstat_generation++; 152 devstat_num_devs--; 153 154 devstat_head = &device_statq; 155 156 /* Remove this entry from the devstat queue */ 157 STAILQ_REMOVE(devstat_head, ds, devstat, dev_links); 158 } 159 160 /* 161 * Record a transaction start. 162 */ 163 void 164 devstat_start_transaction(struct devstat *ds) 165 { 166 int s; 167 168 /* sanity check */ 169 if (ds == NULL) 170 return; 171 172 /* 173 * We only want to set the start time when we are going from idle 174 * to busy. The start time is really the start of the latest busy 175 * period. 176 */ 177 if (ds->busy_count == 0) { 178 s = splclock(); 179 getmicrouptime(&ds->start_time); 180 splx(s); 181 } 182 ds->busy_count++; 183 } 184 185 /* 186 * Record the ending of a transaction, and incrment the various counters. 187 */ 188 void 189 devstat_end_transaction(struct devstat *ds, u_int32_t bytes, 190 devstat_tag_type tag_type, devstat_trans_flags flags) 191 { 192 int s; 193 struct timeval busy_time; 194 195 /* sanity check */ 196 if (ds == NULL) 197 return; 198 199 s = splclock(); 200 getmicrouptime(&ds->last_comp_time); 201 splx(s); 202 203 ds->busy_count--; 204 205 /* 206 * There might be some transactions (DEVSTAT_NO_DATA) that don't 207 * transfer any data. 208 */ 209 if (flags == DEVSTAT_READ) { 210 ds->bytes_read += bytes; 211 ds->num_reads++; 212 } else if (flags == DEVSTAT_WRITE) { 213 ds->bytes_written += bytes; 214 ds->num_writes++; 215 } else 216 ds->num_other++; 217 218 /* 219 * Keep a count of the various tag types sent. 220 */ 221 if (tag_type != DEVSTAT_TAG_NONE) 222 ds->tag_types[tag_type]++; 223 224 /* 225 * We only update the busy time when we go idle. Otherwise, this 226 * calculation would require many more clock cycles. 227 */ 228 if (ds->busy_count == 0) { 229 /* Calculate how long we were busy */ 230 busy_time = ds->last_comp_time; 231 timevalsub(&busy_time, &ds->start_time); 232 233 /* Add our busy time to the total busy time. */ 234 timevaladd(&ds->busy_time, &busy_time); 235 } else if (ds->busy_count < 0) 236 printf("devstat_end_transaction: HELP!! busy_count " 237 "for %s%d is < 0 (%d)!\n", ds->device_name, 238 ds->unit_number, ds->busy_count); 239 } 240 241 /* 242 * This is the sysctl handler for the devstat package. The data pushed out 243 * on the kern.devstat.all sysctl variable consists of the current devstat 244 * generation number, and then an array of devstat structures, one for each 245 * device in the system. 246 * 247 * I'm really not too fond of this method of doing things, but there really 248 * aren't that many alternatives. We must have some method of making sure 249 * that the generation number the user gets corresponds with the data the 250 * user gets. If the user makes a separate sysctl call to get the 251 * generation, and then a sysctl call to get the device statistics, the 252 * device list could have changed in that brief period of time. By 253 * supplying the generation number along with the statistics output, we can 254 * guarantee that the generation number and the statistics match up. 255 */ 256 static int 257 sysctl_devstat SYSCTL_HANDLER_ARGS 258 { 259 int error, i; 260 struct devstat *nds; 261 struct devstatlist *devstat_head; 262 263 if (devstat_num_devs == 0) 264 return(EINVAL); 265 266 error = 0; 267 devstat_head = &device_statq; 268 269 /* 270 * First push out the generation number. 271 */ 272 error = SYSCTL_OUT(req, &devstat_generation, sizeof(long)); 273 274 /* 275 * Now push out all the devices. 276 */ 277 for (i = 0, nds = devstat_head->stqh_first; 278 (nds != NULL) && (i < devstat_num_devs) && (error == 0); 279 nds = nds->dev_links.stqe_next, i++) 280 error = SYSCTL_OUT(req, nds, sizeof(struct devstat)); 281 282 return(error); 283 } 284 285 /* 286 * Sysctl entries for devstat. The first one is a node that all the rest 287 * hang off of. 288 */ 289 SYSCTL_NODE(_kern, OID_AUTO, devstat, CTLFLAG_RD, 0, "Device Statistics"); 290 291 SYSCTL_PROC(_kern_devstat, OID_AUTO, all, CTLFLAG_RD|CTLTYPE_OPAQUE, 292 0, 0, sysctl_devstat, "S,devstat", "All devices in the devstat list"); 293 /* 294 * Export the number of devices in the system so that userland utilities 295 * can determine how much memory to allocate to hold all the devices. 296 */ 297 SYSCTL_INT(_kern_devstat, OID_AUTO, numdevs, CTLFLAG_RD, 298 &devstat_num_devs, 0, "Number of devices in the devstat list"); 299 SYSCTL_LONG(_kern_devstat, OID_AUTO, generation, CTLFLAG_RD, 300 &devstat_generation, "Devstat list generation"); 301 SYSCTL_INT(_kern_devstat, OID_AUTO, version, CTLFLAG_RD, 302 &devstat_version, 0, "Devstat list version number"); 303