1 /* 2 * Copyright (c) 1997, 1998 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 1.7 1998/12/04 22:54:51 archie 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 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 { 57 int s; 58 struct devstatlist *devstat_head; 59 60 if (ds == NULL) 61 return; 62 63 if (devstat_num_devs == 0) 64 STAILQ_INIT(&device_statq); 65 66 devstat_generation++; 67 devstat_num_devs++; 68 69 devstat_head = &device_statq; 70 71 STAILQ_INSERT_TAIL(devstat_head, ds, dev_links); 72 73 ds->device_number = devstat_current_devnumber++; 74 ds->unit_number = unit_number; 75 strncpy(ds->device_name, dev_name, DEVSTAT_NAME_LEN); 76 ds->device_name[DEVSTAT_NAME_LEN - 1] = 0; 77 ds->block_size = block_size; 78 ds->flags = flags; 79 ds->device_type = device_type; 80 81 s = splclock(); 82 getmicrotime(&ds->dev_creation_time); 83 splx(s); 84 } 85 86 /* 87 * Remove a devstat structure from the list of devices. 88 */ 89 void 90 devstat_remove_entry(struct devstat *ds) 91 { 92 struct devstatlist *devstat_head; 93 94 if (ds == NULL) 95 return; 96 97 devstat_generation++; 98 devstat_num_devs--; 99 100 devstat_head = &device_statq; 101 102 /* Remove this entry from the devstat queue */ 103 STAILQ_REMOVE(devstat_head, ds, devstat, dev_links); 104 } 105 106 /* 107 * Record a transaction start. 108 */ 109 void 110 devstat_start_transaction(struct devstat *ds) 111 { 112 int s; 113 114 /* sanity check */ 115 if (ds == NULL) 116 return; 117 118 /* 119 * We only want to set the start time when we are going from idle 120 * to busy. The start time is really the start of the latest busy 121 * period. 122 */ 123 if (ds->busy_count == 0) { 124 s = splclock(); 125 getmicrouptime(&ds->start_time); 126 splx(s); 127 } 128 ds->busy_count++; 129 } 130 131 /* 132 * Record the ending of a transaction, and incrment the various counters. 133 */ 134 void 135 devstat_end_transaction(struct devstat *ds, u_int32_t bytes, 136 devstat_tag_type tag_type, devstat_trans_flags flags) 137 { 138 int s; 139 struct timeval busy_time; 140 141 /* sanity check */ 142 if (ds == NULL) 143 return; 144 145 s = splclock(); 146 getmicrouptime(&ds->last_comp_time); 147 splx(s); 148 149 ds->busy_count--; 150 151 /* 152 * There might be some transactions (DEVSTAT_NO_DATA) that don't 153 * transfer any data. 154 */ 155 if (flags == DEVSTAT_READ) { 156 ds->bytes_read += bytes; 157 ds->num_reads++; 158 } else if (flags == DEVSTAT_WRITE) { 159 ds->bytes_written += bytes; 160 ds->num_writes++; 161 } else 162 ds->num_other++; 163 164 /* 165 * Keep a count of the various tag types sent. 166 */ 167 if (tag_type != DEVSTAT_TAG_NONE) 168 ds->tag_types[tag_type]++; 169 170 /* 171 * We only update the busy time when we go idle. Otherwise, this 172 * calculation would require many more clock cycles. 173 */ 174 if (ds->busy_count == 0) { 175 /* Calculate how long we were busy */ 176 busy_time = ds->last_comp_time; 177 timevalsub(&busy_time, &ds->start_time); 178 179 /* Add our busy time to the total busy time. */ 180 timevaladd(&ds->busy_time, &busy_time); 181 } else if (ds->busy_count < 0) 182 printf("devstat_end_transaction: HELP!! busy_count " 183 "for %s%d is < 0 (%d)!\n", ds->device_name, 184 ds->unit_number, ds->busy_count); 185 } 186 187 /* 188 * This is the sysctl handler for the devstat package. The data pushed out 189 * on the kern.devstat.all sysctl variable consists of the current devstat 190 * generation number, and then an array of devstat structures, one for each 191 * device in the system. 192 * 193 * I'm really not too fond of this method of doing things, but there really 194 * aren't that many alternatives. We must have some method of making sure 195 * that the generation number the user gets corresponds with the data the 196 * user gets. If the user makes a separate sysctl call to get the 197 * generation, and then a sysctl call to get the device statistics, the 198 * device list could have changed in that brief period of time. By 199 * supplying the generation number along with the statistics output, we can 200 * guarantee that the generation number and the statistics match up. 201 */ 202 static int 203 sysctl_devstat SYSCTL_HANDLER_ARGS 204 { 205 int error, i; 206 struct devstat *nds; 207 struct devstatlist *devstat_head; 208 209 if (devstat_num_devs == 0) 210 return(EINVAL); 211 212 error = 0; 213 devstat_head = &device_statq; 214 215 /* 216 * First push out the generation number. 217 */ 218 error = SYSCTL_OUT(req, &devstat_generation, sizeof(long)); 219 220 /* 221 * Now push out all the devices. 222 */ 223 for (i = 0, nds = devstat_head->stqh_first; 224 (nds != NULL) && (i < devstat_num_devs) && (error == 0); 225 nds = nds->dev_links.stqe_next, i++) 226 error = SYSCTL_OUT(req, nds, sizeof(struct devstat)); 227 228 return(error); 229 } 230 231 /* 232 * Sysctl entries for devstat. The first one is a node that all the rest 233 * hang off of. 234 */ 235 SYSCTL_NODE(_kern, OID_AUTO, devstat, CTLFLAG_RD, 0, "Device Statistics"); 236 237 SYSCTL_PROC(_kern_devstat, OID_AUTO, all, CTLFLAG_RD|CTLTYPE_OPAQUE, 238 0, 0, sysctl_devstat, "S,devstat", "All Devices"); 239 /* 240 * Export the number of devices in the system so that userland utilities 241 * can determine how much memory to allocate to hold all the devices. 242 */ 243 SYSCTL_INT(_kern_devstat, OID_AUTO, numdevs, CTLFLAG_RD, &devstat_num_devs, 244 0, "Number of devices in the devstat list"); 245 SYSCTL_LONG(_kern_devstat, OID_AUTO, generation, CTLFLAG_RD, 246 &devstat_generation, "Devstat list generation"); 247 SYSCTL_INT(_kern_devstat, OID_AUTO, version, CTLFLAG_RD, &devstat_version, 248 0, "Devstat list version number"); 249