2 * Copyright (c) 1997, 1998 Kenneth D. Merry.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
28 * $FreeBSD: src/lib/libdevstat/devstat.c,v 1.6 1999/08/28 00:04:26 peter Exp $
29 * $DragonFly: src/lib/libdevstat/devstat.c,v 1.2 2003/06/17 04:26:49 dillon Exp $
32 #include <sys/types.h>
33 #include <sys/sysctl.h>
34 #include <sys/errno.h>
35 #include <sys/dkstat.h>
45 char devstat_errbuf[DEVSTAT_ERRBUF_SIZE];
48 * Table to match descriptive strings with device types. These are in
49 * order from most common to least common to speed search time.
51 struct devstat_match_table match_table[] = {
52 {"da", DEVSTAT_TYPE_DIRECT, DEVSTAT_MATCH_TYPE},
53 {"cd", DEVSTAT_TYPE_CDROM, DEVSTAT_MATCH_TYPE},
54 {"scsi", DEVSTAT_TYPE_IF_SCSI, DEVSTAT_MATCH_IF},
55 {"ide", DEVSTAT_TYPE_IF_IDE, DEVSTAT_MATCH_IF},
56 {"other", DEVSTAT_TYPE_IF_OTHER, DEVSTAT_MATCH_IF},
57 {"worm", DEVSTAT_TYPE_WORM, DEVSTAT_MATCH_TYPE},
58 {"sa", DEVSTAT_TYPE_SEQUENTIAL,DEVSTAT_MATCH_TYPE},
59 {"pass", DEVSTAT_TYPE_PASS, DEVSTAT_MATCH_PASS},
60 {"optical", DEVSTAT_TYPE_OPTICAL, DEVSTAT_MATCH_TYPE},
61 {"array", DEVSTAT_TYPE_STORARRAY, DEVSTAT_MATCH_TYPE},
62 {"changer", DEVSTAT_TYPE_CHANGER, DEVSTAT_MATCH_TYPE},
63 {"scanner", DEVSTAT_TYPE_SCANNER, DEVSTAT_MATCH_TYPE},
64 {"printer", DEVSTAT_TYPE_PRINTER, DEVSTAT_MATCH_TYPE},
65 {"floppy", DEVSTAT_TYPE_FLOPPY, DEVSTAT_MATCH_TYPE},
66 {"proc", DEVSTAT_TYPE_PROCESSOR, DEVSTAT_MATCH_TYPE},
67 {"comm", DEVSTAT_TYPE_COMM, DEVSTAT_MATCH_TYPE},
68 {"enclosure", DEVSTAT_TYPE_ENCLOSURE, DEVSTAT_MATCH_TYPE},
73 * Local function declarations.
75 static int compare_select(const void *arg1, const void *arg2);
82 char *func_name = "getnumdevs";
84 numdevsize = sizeof(int);
87 * Find out how many devices we have in the system.
89 if (sysctlbyname("kern.devstat.numdevs", &numdevs,
90 &numdevsize, NULL, 0) == -1) {
91 sprintf(devstat_errbuf, "%s: error getting number of devices\n"
92 "%s: %s", func_name, func_name, strerror(errno));
99 * This is an easy way to get the generation number, but the generation is
100 * supplied in a more atmoic manner by the kern.devstat.all sysctl.
101 * Because this generation sysctl is separate from the statistics sysctl,
102 * the device list and the generation could change between the time that
103 * this function is called and the device list is retreived.
110 char *func_name = "getgeneration";
112 gensize = sizeof(long);
115 * Get the current generation number.
117 if (sysctlbyname("kern.devstat.generation", &generation,
118 &gensize, NULL, 0) == -1) {
119 sprintf(devstat_errbuf,"%s: error getting devstat generation\n"
120 "%s: %s", func_name, func_name, strerror(errno));
127 * Get the current devstat version. The return value of this function
128 * should be compared with DEVSTAT_VERSION, which is defined in
129 * sys/devicestat.h. This will enable userland programs to determine
130 * whether they are out of sync with the kernel.
137 char *func_name = "getversion";
139 versize = sizeof(int);
142 * Get the current devstat version.
144 if (sysctlbyname("kern.devstat.version", &version, &versize,
146 sprintf(devstat_errbuf, "%s: error getting devstat version\n"
147 "%s: %s", func_name, func_name, strerror(errno));
154 * Check the devstat version we know about against the devstat version the
155 * kernel knows about. If they don't match, print an error into the
156 * devstat error buffer, and return -1. If they match, return 0.
163 char *func_name = "checkversion";
166 version = getversion();
168 if (version != DEVSTAT_VERSION) {
173 * This is really pretty silly, but basically the idea is
174 * that if getversion() returns an error (i.e. -1), then it
175 * has printed an error message in the buffer. Therefore,
176 * we need to add a \n to the end of that message before we
177 * print our own message in the buffer.
180 buflen = strlen(devstat_errbuf);
181 errlen = snprintf(tmpstr, sizeof(tmpstr), "\n");
182 strncat(devstat_errbuf, tmpstr,
183 DEVSTAT_ERRBUF_SIZE - buflen - 1);
187 errlen = snprintf(tmpstr, sizeof(tmpstr),
188 "%s: userland devstat version %d is not "
189 "the same as the kernel\n%s: devstat "
190 "version %d\n", func_name, DEVSTAT_VERSION,
194 strncat(devstat_errbuf, tmpstr,
195 DEVSTAT_ERRBUF_SIZE - buflen - 1);
198 strncpy(devstat_errbuf, tmpstr, DEVSTAT_ERRBUF_SIZE);
199 devstat_errbuf[DEVSTAT_ERRBUF_SIZE - 1] = '\0';
202 if (version < DEVSTAT_VERSION)
203 snprintf(tmpstr, sizeof(tmpstr),
204 "%s: libdevstat newer than kernel\n",
207 snprintf(tmpstr, sizeof(tmpstr),
208 "%s: kernel newer than libdevstat\n",
211 strncat(devstat_errbuf, tmpstr,
212 DEVSTAT_ERRBUF_SIZE - buflen - 1);
221 * Get the current list of devices and statistics, and the current
226 * 0 -- device list is unchanged
227 * 1 -- device list has changed
230 getdevs(struct statinfo *stats)
237 struct devinfo *dinfo;
238 char *func_name = "getdevs";
240 dinfo = stats->dinfo;
243 sprintf(devstat_errbuf, "%s: stats->dinfo was NULL", func_name);
247 oldnumdevs = dinfo->numdevs;
248 oldgeneration = dinfo->generation;
251 * If this is our first time through, mem_ptr will be null.
253 if (dinfo->mem_ptr == NULL) {
255 * Get the number of devices. If it's negative, it's an
256 * error. Don't bother setting the error string, since
257 * getnumdevs() has already done that for us.
259 if ((dinfo->numdevs = getnumdevs()) < 0)
263 * The kern.devstat.all sysctl returns the current generation
264 * number, as well as all the devices. So we need four
267 dssize =(dinfo->numdevs * sizeof(struct devstat)) +sizeof(long);
268 dinfo->mem_ptr = (u_int8_t *)malloc(dssize);
270 dssize =(dinfo->numdevs * sizeof(struct devstat)) +sizeof(long);
272 /* Get the current time when we get the stats */
273 gettimeofday(&stats->busy_time, NULL);
276 * Request all of the devices. We only really allow for one
277 * ENOMEM failure. It would, of course, be possible to just go in
278 * a loop and keep reallocing the device structure until we don't
279 * get ENOMEM back. I'm not sure it's worth it, though. If
280 * devices are being added to the system that quickly, maybe the
281 * user can just wait until all devices are added.
283 if ((error = sysctlbyname("kern.devstat.all", dinfo->mem_ptr,
284 &dssize, NULL, 0)) == -1) {
286 * If we get ENOMEM back, that means that there are
287 * more devices now, so we need to allocate more
288 * space for the device array.
290 if (errno == ENOMEM) {
292 * No need to set the error string here, getnumdevs()
293 * will do that if it fails.
295 if ((dinfo->numdevs = getnumdevs()) < 0)
298 dssize = (dinfo->numdevs * sizeof(struct devstat)) +
300 dinfo->mem_ptr = (u_int8_t *)realloc(dinfo->mem_ptr,
302 if ((error = sysctlbyname("kern.devstat.all",
303 dinfo->mem_ptr, &dssize, NULL, 0)) == -1) {
304 sprintf(devstat_errbuf,
305 "%s: error getting device stats\n"
306 "%s: %s", func_name, func_name,
311 sprintf(devstat_errbuf,
312 "%s: error getting device stats\n"
313 "%s: %s", func_name, func_name,
320 * The sysctl spits out the generation as the first four bytes,
321 * then all of the device statistics structures.
323 dinfo->generation = *(long *)dinfo->mem_ptr;
326 * If the generation has changed, and if the current number of
327 * devices is not the same as the number of devices recorded in the
328 * devinfo structure, it is likely that the device list has shrunk.
329 * The reason that it is likely that the device list has shrunk in
330 * this case is that if the device list has grown, the sysctl above
331 * will return an ENOMEM error, and we will reset the number of
332 * devices and reallocate the device array. If the second sysctl
333 * fails, we will return an error and therefore never get to this
334 * point. If the device list has shrunk, the sysctl will not
335 * return an error since we have more space allocated than is
336 * necessary. So, in the shrinkage case, we catch it here and
337 * reallocate the array so that we don't use any more space than is
340 if (oldgeneration != dinfo->generation) {
341 if (getnumdevs() != dinfo->numdevs) {
342 if ((dinfo->numdevs = getnumdevs()) < 0)
344 dssize = (dinfo->numdevs * sizeof(struct devstat)) +
346 dinfo->mem_ptr = (u_int8_t *)realloc(dinfo->mem_ptr,
352 dinfo->devices = (struct devstat *)(dinfo->mem_ptr + sizeof(long));
360 * Devices are selected/deselected based upon the following criteria:
361 * - devices specified by the user on the command line
362 * - devices matching any device type expressions given on the command line
363 * - devices with the highest I/O, if 'top' mode is enabled
364 * - the first n unselected devices in the device list, if maxshowdevs
365 * devices haven't already been selected and if the user has not
366 * specified any devices on the command line and if we're in "add" mode.
369 * - device selection list (dev_select)
370 * - current number of devices selected (num_selected)
371 * - total number of devices in the selection list (num_selections)
372 * - devstat generation as of the last time selectdevs() was called
373 * (select_generation)
374 * - current devstat generation (current_generation)
375 * - current list of devices and statistics (devices)
376 * - number of devices in the current device list (numdevs)
377 * - compiled version of the command line device type arguments (matches)
378 * - This is optional. If the number of devices is 0, this will be ignored.
379 * - The matching code pays attention to the current selection mode. So
380 * if you pass in a matching expression, it will be evaluated based
381 * upon the selection mode that is passed in. See below for details.
382 * - number of device type matching expressions (num_matches)
383 * - Set to 0 to disable the matching code.
384 * - list of devices specified on the command line by the user (dev_selections)
385 * - number of devices selected on the command line by the user
386 * (num_dev_selections)
387 * - Our selection mode. There are four different selection modes:
388 * - add mode. (DS_SELECT_ADD) Any devices matching devices explicitly
389 * selected by the user or devices matching a pattern given by the
390 * user will be selected in addition to devices that are already
391 * selected. Additional devices will be selected, up to maxshowdevs
393 * - only mode. (DS_SELECT_ONLY) Only devices matching devices
394 * explicitly given by the user or devices matching a pattern
395 * given by the user will be selected. No other devices will be
397 * - addonly mode. (DS_SELECT_ADDONLY) This is similar to add and
398 * only. Basically, this will not de-select any devices that are
399 * current selected, as only mode would, but it will also not
400 * gratuitously select up to maxshowdevs devices as add mode would.
401 * - remove mode. (DS_SELECT_REMOVE) Any devices matching devices
402 * explicitly selected by the user or devices matching a pattern
403 * given by the user will be de-selected.
404 * - maximum number of devices we can select (maxshowdevs)
405 * - flag indicating whether or not we're in 'top' mode (perf_select)
408 * - the device selection list may be modified and passed back out
409 * - the number of devices selected and the total number of items in the
410 * device selection list may be changed
411 * - the selection generation may be changed to match the current generation
415 * 0 -- selected devices are unchanged
416 * 1 -- selected devices changed
419 selectdevs(struct device_selection **dev_select, int *num_selected,
420 int *num_selections, long *select_generation,
421 long current_generation, struct devstat *devices, int numdevs,
422 struct devstat_match *matches, int num_matches,
423 char **dev_selections, int num_dev_selections,
424 devstat_select_mode select_mode, int maxshowdevs, int perf_select)
426 register int i, j, k;
427 int init_selections = 0, init_selected_var = 0;
428 struct device_selection *old_dev_select = NULL;
429 int old_num_selections = 0, old_num_selected;
430 int selection_number = 0;
431 int changed = 0, found = 0;
433 if ((dev_select == NULL) || (devices == NULL) || (numdevs <= 0))
437 * We always want to make sure that we have as many dev_select
438 * entries as there are devices.
441 * In this case, we haven't selected devices before.
443 if (*dev_select == NULL) {
444 *dev_select = (struct device_selection *)malloc(numdevs *
445 sizeof(struct device_selection));
446 *select_generation = current_generation;
450 * In this case, we have selected devices before, but the device
451 * list has changed since we last selected devices, so we need to
452 * either enlarge or reduce the size of the device selection list.
454 } else if (*num_selections != numdevs) {
455 *dev_select = (struct device_selection *)realloc(*dev_select,
456 numdevs * sizeof(struct device_selection));
457 *select_generation = current_generation;
460 * In this case, we've selected devices before, and the selection
461 * list is the same size as it was the last time, but the device
464 } else if (*select_generation < current_generation) {
465 *select_generation = current_generation;
470 * If we're in "only" mode, we want to clear out the selected
471 * variable since we're going to select exactly what the user wants
474 if (select_mode == DS_SELECT_ONLY)
475 init_selected_var = 1;
478 * In all cases, we want to back up the number of selected devices.
479 * It is a quick and accurate way to determine whether the selected
480 * devices have changed.
482 old_num_selected = *num_selected;
485 * We want to make a backup of the current selection list if
486 * the list of devices has changed, or if we're in performance
487 * selection mode. In both cases, we don't want to make a backup
488 * if we already know for sure that the list will be different.
489 * This is certainly the case if this is our first time through the
492 if (((init_selected_var != 0) || (init_selections != 0)
493 || (perf_select != 0)) && (changed == 0)){
494 old_dev_select = (struct device_selection *)malloc(
495 *num_selections * sizeof(struct device_selection));
496 old_num_selections = *num_selections;
497 bcopy(*dev_select, old_dev_select,
498 sizeof(struct device_selection) * *num_selections);
501 if (init_selections != 0) {
502 bzero(*dev_select, sizeof(struct device_selection) * numdevs);
504 for (i = 0; i < numdevs; i++) {
505 (*dev_select)[i].device_number =
506 devices[i].device_number;
507 strncpy((*dev_select)[i].device_name,
508 devices[i].device_name,
510 (*dev_select)[i].device_name[DEVSTAT_NAME_LEN - 1]='\0';
511 (*dev_select)[i].unit_number = devices[i].unit_number;
512 (*dev_select)[i].position = i;
514 *num_selections = numdevs;
515 } else if (init_selected_var != 0) {
516 for (i = 0; i < numdevs; i++)
517 (*dev_select)[i].selected = 0;
520 /* we haven't gotten around to selecting anything yet.. */
521 if ((select_mode == DS_SELECT_ONLY) || (init_selections != 0)
522 || (init_selected_var != 0))
526 * Look through any devices the user specified on the command line
527 * and see if they match known devices. If so, select them.
529 for (i = 0; (i < *num_selections) && (num_dev_selections > 0); i++) {
532 snprintf(tmpstr, sizeof(tmpstr), "%s%d",
533 (*dev_select)[i].device_name,
534 (*dev_select)[i].unit_number);
535 for (j = 0; j < num_dev_selections; j++) {
536 if (strcmp(tmpstr, dev_selections[j]) == 0) {
538 * Here we do different things based on the
539 * mode we're in. If we're in add or
540 * addonly mode, we only select this device
541 * if it hasn't already been selected.
542 * Otherwise, we would be unnecessarily
543 * changing the selection order and
544 * incrementing the selection count. If
545 * we're in only mode, we unconditionally
546 * select this device, since in only mode
547 * any previous selections are erased and
548 * manually specified devices are the first
549 * ones to be selected. If we're in remove
550 * mode, we de-select the specified device and
551 * decrement the selection count.
553 switch(select_mode) {
555 case DS_SELECT_ADDONLY:
556 if ((*dev_select)[i].selected)
560 (*dev_select)[i].selected =
564 case DS_SELECT_REMOVE:
565 (*dev_select)[i].selected = 0;
568 * This isn't passed back out, we
569 * just use it to keep track of
570 * how many devices we've removed.
572 num_dev_selections--;
581 * Go through the user's device type expressions and select devices
582 * accordingly. We only do this if the number of devices already
583 * selected is less than the maximum number we can show.
585 for (i = 0; (i < num_matches) && (*num_selected < maxshowdevs); i++) {
586 /* We should probably indicate some error here */
587 if ((matches[i].match_fields == DEVSTAT_MATCH_NONE)
588 || (matches[i].num_match_categories <= 0))
591 for (j = 0; j < numdevs; j++) {
592 int num_match_categories;
594 num_match_categories = matches[i].num_match_categories;
597 * Determine whether or not the current device
598 * matches the given matching expression. This if
599 * statement consists of three components:
600 * - the device type check
601 * - the device interface check
602 * - the passthrough check
603 * If a the matching test is successful, it
604 * decrements the number of matching categories,
605 * and if we've reached the last element that
606 * needed to be matched, the if statement succeeds.
609 if ((((matches[i].match_fields & DEVSTAT_MATCH_TYPE)!=0)
610 && ((devices[j].device_type & DEVSTAT_TYPE_MASK) ==
611 (matches[i].device_type & DEVSTAT_TYPE_MASK))
612 &&(((matches[i].match_fields & DEVSTAT_MATCH_PASS)!=0)
613 || (((matches[i].match_fields &
614 DEVSTAT_MATCH_PASS) == 0)
615 && ((devices[j].device_type &
616 DEVSTAT_TYPE_PASS) == 0)))
617 && (--num_match_categories == 0))
618 || (((matches[i].match_fields & DEVSTAT_MATCH_IF) != 0)
619 && ((devices[j].device_type & DEVSTAT_TYPE_IF_MASK) ==
620 (matches[i].device_type & DEVSTAT_TYPE_IF_MASK))
621 &&(((matches[i].match_fields & DEVSTAT_MATCH_PASS)!=0)
622 || (((matches[i].match_fields &
623 DEVSTAT_MATCH_PASS) == 0)
624 && ((devices[j].device_type &
625 DEVSTAT_TYPE_PASS) == 0)))
626 && (--num_match_categories == 0))
627 || (((matches[i].match_fields & DEVSTAT_MATCH_PASS)!=0)
628 && ((devices[j].device_type & DEVSTAT_TYPE_PASS) != 0)
629 && (--num_match_categories == 0))) {
632 * This is probably a non-optimal solution
633 * to the problem that the devices in the
634 * device list will not be in the same
635 * order as the devices in the selection
638 for (k = 0; k < numdevs; k++) {
639 if ((*dev_select)[k].position == j) {
646 * There shouldn't be a case where a device
647 * in the device list is not in the
648 * selection list...but it could happen.
651 fprintf(stderr, "selectdevs: couldn't"
652 " find %s%d in selection "
654 devices[j].device_name,
655 devices[j].unit_number);
660 * We do different things based upon the
661 * mode we're in. If we're in add or only
662 * mode, we go ahead and select this device
663 * if it hasn't already been selected. If
664 * it has already been selected, we leave
665 * it alone so we don't mess up the
666 * selection ordering. Manually specified
667 * devices have already been selected, and
668 * they have higher priority than pattern
669 * matched devices. If we're in remove
670 * mode, we de-select the given device and
671 * decrement the selected count.
673 switch(select_mode) {
675 case DS_SELECT_ADDONLY:
677 if ((*dev_select)[k].selected != 0)
679 (*dev_select)[k].selected =
683 case DS_SELECT_REMOVE:
684 (*dev_select)[k].selected = 0;
693 * Here we implement "top" mode. Devices are sorted in the
694 * selection array based on two criteria: whether or not they are
695 * selected (not selection number, just the fact that they are
696 * selected!) and the number of bytes in the "bytes" field of the
697 * selection structure. The bytes field generally must be kept up
698 * by the user. In the future, it may be maintained by library
699 * functions, but for now the user has to do the work.
701 * At first glance, it may seem wrong that we don't go through and
702 * select every device in the case where the user hasn't specified
703 * any devices or patterns. In fact, though, it won't make any
704 * difference in the device sorting. In that particular case (i.e.
705 * when we're in "add" or "only" mode, and the user hasn't
706 * specified anything) the first time through no devices will be
707 * selected, so the only criterion used to sort them will be their
708 * performance. The second time through, and every time thereafter,
709 * all devices will be selected, so again selection won't matter.
711 if (perf_select != 0) {
713 /* Sort the device array by throughput */
714 qsort(*dev_select, *num_selections,
715 sizeof(struct device_selection),
718 if (*num_selected == 0) {
720 * Here we select every device in the array, if it
721 * isn't already selected. Because the 'selected'
722 * variable in the selection array entries contains
723 * the selection order, the devstats routine can show
724 * the devices that were selected first.
726 for (i = 0; i < *num_selections; i++) {
727 if ((*dev_select)[i].selected == 0) {
728 (*dev_select)[i].selected =
734 selection_number = 0;
735 for (i = 0; i < *num_selections; i++) {
736 if ((*dev_select)[i].selected != 0) {
737 (*dev_select)[i].selected =
745 * If we're in the "add" selection mode and if we haven't already
746 * selected maxshowdevs number of devices, go through the array and
747 * select any unselected devices. If we're in "only" mode, we
748 * obviously don't want to select anything other than what the user
749 * specifies. If we're in "remove" mode, it probably isn't a good
750 * idea to go through and select any more devices, since we might
751 * end up selecting something that the user wants removed. Through
752 * more complicated logic, we could actually figure this out, but
753 * that would probably require combining this loop with the various
754 * selections loops above.
756 if ((select_mode == DS_SELECT_ADD) && (*num_selected < maxshowdevs)) {
757 for (i = 0; i < *num_selections; i++)
758 if ((*dev_select)[i].selected == 0) {
759 (*dev_select)[i].selected = ++selection_number;
765 * Look at the number of devices that have been selected. If it
766 * has changed, set the changed variable. Otherwise, if we've
767 * made a backup of the selection list, compare it to the current
768 * selection list to see if the selected devices have changed.
770 if ((changed == 0) && (old_num_selected != *num_selected))
772 else if ((changed == 0) && (old_dev_select != NULL)) {
774 * Now we go through the selection list and we look at
775 * it three different ways.
777 for (i = 0; (i < *num_selections) && (changed == 0) &&
778 (i < old_num_selections); i++) {
780 * If the device at index i in both the new and old
781 * selection arrays has the same device number and
782 * selection status, it hasn't changed. We
783 * continue on to the next index.
785 if (((*dev_select)[i].device_number ==
786 old_dev_select[i].device_number)
787 && ((*dev_select)[i].selected ==
788 old_dev_select[i].selected))
792 * Now, if we're still going through the if
793 * statement, the above test wasn't true. So we
794 * check here to see if the device at index i in
795 * the current array is the same as the device at
796 * index i in the old array. If it is, that means
797 * that its selection number has changed. Set
798 * changed to 1 and exit the loop.
800 else if ((*dev_select)[i].device_number ==
801 old_dev_select[i].device_number) {
806 * If we get here, then the device at index i in
807 * the current array isn't the same device as the
808 * device at index i in the old array.
814 * Search through the old selection array
815 * looking for a device with the same
816 * device number as the device at index i
817 * in the current array. If the selection
818 * status is the same, then we mark it as
819 * found. If the selection status isn't
820 * the same, we break out of the loop.
821 * Since found isn't set, changed will be
824 for (j = 0; j < old_num_selections; j++) {
825 if (((*dev_select)[i].device_number ==
826 old_dev_select[j].device_number)
827 && ((*dev_select)[i].selected ==
828 old_dev_select[j].selected)){
832 else if ((*dev_select)[i].device_number
833 == old_dev_select[j].device_number)
841 if (old_dev_select != NULL)
842 free(old_dev_select);
848 * Comparison routine for qsort() above. Note that the comparison here is
849 * backwards -- generally, it should return a value to indicate whether
850 * arg1 is <, =, or > arg2. Instead, it returns the opposite. The reason
851 * it returns the opposite is so that the selection array will be sorted in
852 * order of decreasing performance. We sort on two parameters. The first
853 * sort key is whether or not one or the other of the devices in question
854 * has been selected. If one of them has, and the other one has not, the
855 * selected device is automatically more important than the unselected
856 * device. If neither device is selected, we judge the devices based upon
860 compare_select(const void *arg1, const void *arg2)
862 if ((((struct device_selection *)arg1)->selected)
863 && (((struct device_selection *)arg2)->selected == 0))
865 else if ((((struct device_selection *)arg1)->selected == 0)
866 && (((struct device_selection *)arg2)->selected))
868 else if (((struct device_selection *)arg2)->bytes <
869 ((struct device_selection *)arg1)->bytes)
871 else if (((struct device_selection *)arg2)->bytes >
872 ((struct device_selection *)arg1)->bytes)
879 * Take a string with the general format "arg1,arg2,arg3", and build a
880 * device matching expression from it.
883 buildmatch(char *match_str, struct devstat_match **matches, int *num_matches)
889 char *func_name = "buildmatch";
891 /* We can't do much without a string to parse */
892 if (match_str == NULL) {
893 sprintf(devstat_errbuf, "%s: no match expression", func_name);
898 * Break the (comma delimited) input string out into separate strings.
900 for (tempstr = tstr, num_args = 0;
901 (*tempstr = strsep(&match_str, ",")) != NULL && (num_args < 5);
903 if (**tempstr != '\0')
904 if (++tempstr >= &tstr[5])
907 /* The user gave us too many type arguments */
909 sprintf(devstat_errbuf, "%s: too many type arguments",
915 * Since you can't realloc a pointer that hasn't been malloced
916 * first, we malloc first and then realloc.
918 if (*num_matches == 0)
919 *matches = (struct devstat_match *)malloc(
920 sizeof(struct devstat_match));
922 *matches = (struct devstat_match *)realloc(*matches,
923 sizeof(struct devstat_match) * (*num_matches + 1));
925 /* Make sure the current entry is clear */
926 bzero(&matches[0][*num_matches], sizeof(struct devstat_match));
929 * Step through the arguments the user gave us and build a device
930 * matching expression from them.
932 for (i = 0; i < num_args; i++) {
933 char *tempstr2, *tempstr3;
936 * Get rid of leading white space.
939 while (isspace(*tempstr2) && (*tempstr2 != '\0'))
943 * Get rid of trailing white space.
945 tempstr3 = &tempstr2[strlen(tempstr2) - 1];
947 while ((*tempstr3 != '\0') && (tempstr3 > tempstr2)
948 && (isspace(*tempstr3))) {
954 * Go through the match table comparing the user's
955 * arguments to known device types, interfaces, etc.
957 for (j = 0; match_table[j].match_str != NULL; j++) {
959 * We do case-insensitive matching, in case someone
960 * wants to enter "SCSI" instead of "scsi" or
961 * something like that. Only compare as many
962 * characters as are in the string in the match
963 * table. This should help if someone tries to use
964 * a super-long match expression.
966 if (strncasecmp(tempstr2, match_table[j].match_str,
967 strlen(match_table[j].match_str)) == 0) {
969 * Make sure the user hasn't specified two
970 * items of the same type, like "da" and
971 * "cd". One device cannot be both.
973 if (((*matches)[*num_matches].match_fields &
974 match_table[j].match_field) != 0) {
975 sprintf(devstat_errbuf,
976 "%s: cannot have more than "
977 "one match item in a single "
978 "category", func_name);
982 * If we've gotten this far, we have a
983 * winner. Set the appropriate fields in
986 (*matches)[*num_matches].match_fields |=
987 match_table[j].match_field;
988 (*matches)[*num_matches].device_type |=
990 (*matches)[*num_matches].num_match_categories++;
995 * We should have found a match in the above for loop. If
996 * not, that means the user entered an invalid device type
999 if ((*matches)[*num_matches].num_match_categories != (i + 1)) {
1000 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
1001 "%s: unknown match item \"%s\"", func_name,
1013 * Compute a number of device statistics. Only one field is mandatory, and
1014 * that is "current". Everything else is optional. The caller passes in
1015 * pointers to variables to hold the various statistics he desires. If he
1016 * doesn't want a particular staistic, he should pass in a NULL pointer.
1022 compute_stats(struct devstat *current, struct devstat *previous,
1023 long double etime, u_int64_t *total_bytes,
1024 u_int64_t *total_transfers, u_int64_t *total_blocks,
1025 long double *kb_per_transfer, long double *transfers_per_second,
1026 long double *mb_per_second, long double *blocks_per_second,
1027 long double *ms_per_transaction)
1029 u_int64_t totalbytes, totaltransfers, totalblocks;
1030 char *func_name = "compute_stats";
1033 * current is the only mandatory field.
1035 if (current == NULL) {
1036 sprintf(devstat_errbuf, "%s: current stats structure was NULL",
1041 totalbytes = (current->bytes_written + current->bytes_read) -
1042 ((previous) ? (previous->bytes_written +
1043 previous->bytes_read) : 0);
1046 *total_bytes = totalbytes;
1048 totaltransfers = (current->num_reads +
1049 current->num_writes +
1050 current->num_other) -
1052 (previous->num_reads +
1053 previous->num_writes +
1054 previous->num_other) : 0);
1055 if (total_transfers)
1056 *total_transfers = totaltransfers;
1058 if (transfers_per_second) {
1060 *transfers_per_second = totaltransfers;
1061 *transfers_per_second /= etime;
1063 *transfers_per_second = 0.0;
1066 if (kb_per_transfer) {
1067 *kb_per_transfer = totalbytes;
1068 *kb_per_transfer /= 1024;
1069 if (totaltransfers > 0)
1070 *kb_per_transfer /= totaltransfers;
1072 *kb_per_transfer = 0.0;
1075 if (mb_per_second) {
1076 *mb_per_second = totalbytes;
1077 *mb_per_second /= 1024 * 1024;
1079 *mb_per_second /= etime;
1081 *mb_per_second = 0.0;
1084 totalblocks = totalbytes;
1085 if (current->block_size > 0)
1086 totalblocks /= current->block_size;
1091 *total_blocks = totalblocks;
1093 if (blocks_per_second) {
1094 *blocks_per_second = totalblocks;
1096 *blocks_per_second /= etime;
1098 *blocks_per_second = 0.0;
1101 if (ms_per_transaction) {
1102 if (totaltransfers > 0) {
1103 *ms_per_transaction = etime;
1104 *ms_per_transaction /= totaltransfers;
1105 *ms_per_transaction *= 1000;
1107 *ms_per_transaction = 0.0;
1114 compute_etime(struct timeval cur_time, struct timeval prev_time)
1116 struct timeval busy_time;
1117 u_int64_t busy_usec;
1120 timersub(&cur_time, &prev_time, &busy_time);
1122 busy_usec = busy_time.tv_sec;
1123 busy_usec *= 1000000;
1124 busy_usec += busy_time.tv_usec;