2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1997, 1998 Kenneth D. Merry.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. The name of the author may not be used to endorse or promote products
16 * derived from this software without specific prior written permission.
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
34 #include <sys/types.h>
35 #include <sys/sysctl.h>
36 #include <sys/errno.h>
37 #include <sys/resource.h>
38 #include <sys/queue.h>
54 compute_stats(struct devstat *current, struct devstat *previous,
55 long double etime, u_int64_t *total_bytes,
56 u_int64_t *total_transfers, u_int64_t *total_blocks,
57 long double *kb_per_transfer, long double *transfers_per_second,
58 long double *mb_per_second, long double *blocks_per_second,
59 long double *ms_per_transaction);
68 char devstat_errbuf[DEVSTAT_ERRBUF_SIZE];
71 * Table to match descriptive strings with device types. These are in
72 * order from most common to least common to speed search time.
74 struct devstat_match_table match_table[] = {
75 {"da", DEVSTAT_TYPE_DIRECT, DEVSTAT_MATCH_TYPE},
76 {"cd", DEVSTAT_TYPE_CDROM, DEVSTAT_MATCH_TYPE},
77 {"scsi", DEVSTAT_TYPE_IF_SCSI, DEVSTAT_MATCH_IF},
78 {"ide", DEVSTAT_TYPE_IF_IDE, DEVSTAT_MATCH_IF},
79 {"other", DEVSTAT_TYPE_IF_OTHER, DEVSTAT_MATCH_IF},
80 {"worm", DEVSTAT_TYPE_WORM, DEVSTAT_MATCH_TYPE},
81 {"sa", DEVSTAT_TYPE_SEQUENTIAL,DEVSTAT_MATCH_TYPE},
82 {"pass", DEVSTAT_TYPE_PASS, DEVSTAT_MATCH_PASS},
83 {"optical", DEVSTAT_TYPE_OPTICAL, DEVSTAT_MATCH_TYPE},
84 {"array", DEVSTAT_TYPE_STORARRAY, DEVSTAT_MATCH_TYPE},
85 {"changer", DEVSTAT_TYPE_CHANGER, DEVSTAT_MATCH_TYPE},
86 {"scanner", DEVSTAT_TYPE_SCANNER, DEVSTAT_MATCH_TYPE},
87 {"printer", DEVSTAT_TYPE_PRINTER, DEVSTAT_MATCH_TYPE},
88 {"floppy", DEVSTAT_TYPE_FLOPPY, DEVSTAT_MATCH_TYPE},
89 {"proc", DEVSTAT_TYPE_PROCESSOR, DEVSTAT_MATCH_TYPE},
90 {"comm", DEVSTAT_TYPE_COMM, DEVSTAT_MATCH_TYPE},
91 {"enclosure", DEVSTAT_TYPE_ENCLOSURE, DEVSTAT_MATCH_TYPE},
96 devstat_metric metric;
97 devstat_arg_type argtype;
98 } devstat_arg_list[] = {
99 { DSM_NONE, DEVSTAT_ARG_NOTYPE },
100 { DSM_TOTAL_BYTES, DEVSTAT_ARG_UINT64 },
101 { DSM_TOTAL_BYTES_READ, DEVSTAT_ARG_UINT64 },
102 { DSM_TOTAL_BYTES_WRITE, DEVSTAT_ARG_UINT64 },
103 { DSM_TOTAL_TRANSFERS, DEVSTAT_ARG_UINT64 },
104 { DSM_TOTAL_TRANSFERS_READ, DEVSTAT_ARG_UINT64 },
105 { DSM_TOTAL_TRANSFERS_WRITE, DEVSTAT_ARG_UINT64 },
106 { DSM_TOTAL_TRANSFERS_OTHER, DEVSTAT_ARG_UINT64 },
107 { DSM_TOTAL_BLOCKS, DEVSTAT_ARG_UINT64 },
108 { DSM_TOTAL_BLOCKS_READ, DEVSTAT_ARG_UINT64 },
109 { DSM_TOTAL_BLOCKS_WRITE, DEVSTAT_ARG_UINT64 },
110 { DSM_KB_PER_TRANSFER, DEVSTAT_ARG_LD },
111 { DSM_KB_PER_TRANSFER_READ, DEVSTAT_ARG_LD },
112 { DSM_KB_PER_TRANSFER_WRITE, DEVSTAT_ARG_LD },
113 { DSM_TRANSFERS_PER_SECOND, DEVSTAT_ARG_LD },
114 { DSM_TRANSFERS_PER_SECOND_READ, DEVSTAT_ARG_LD },
115 { DSM_TRANSFERS_PER_SECOND_WRITE, DEVSTAT_ARG_LD },
116 { DSM_TRANSFERS_PER_SECOND_OTHER, DEVSTAT_ARG_LD },
117 { DSM_MB_PER_SECOND, DEVSTAT_ARG_LD },
118 { DSM_MB_PER_SECOND_READ, DEVSTAT_ARG_LD },
119 { DSM_MB_PER_SECOND_WRITE, DEVSTAT_ARG_LD },
120 { DSM_BLOCKS_PER_SECOND, DEVSTAT_ARG_LD },
121 { DSM_BLOCKS_PER_SECOND_READ, DEVSTAT_ARG_LD },
122 { DSM_BLOCKS_PER_SECOND_WRITE, DEVSTAT_ARG_LD },
123 { DSM_MS_PER_TRANSACTION, DEVSTAT_ARG_LD },
124 { DSM_MS_PER_TRANSACTION_READ, DEVSTAT_ARG_LD },
125 { DSM_MS_PER_TRANSACTION_WRITE, DEVSTAT_ARG_LD },
126 { DSM_SKIP, DEVSTAT_ARG_SKIP },
127 { DSM_TOTAL_BYTES_FREE, DEVSTAT_ARG_UINT64 },
128 { DSM_TOTAL_TRANSFERS_FREE, DEVSTAT_ARG_UINT64 },
129 { DSM_TOTAL_BLOCKS_FREE, DEVSTAT_ARG_UINT64 },
130 { DSM_KB_PER_TRANSFER_FREE, DEVSTAT_ARG_LD },
131 { DSM_MB_PER_SECOND_FREE, DEVSTAT_ARG_LD },
132 { DSM_TRANSFERS_PER_SECOND_FREE, DEVSTAT_ARG_LD },
133 { DSM_BLOCKS_PER_SECOND_FREE, DEVSTAT_ARG_LD },
134 { DSM_MS_PER_TRANSACTION_OTHER, DEVSTAT_ARG_LD },
135 { DSM_MS_PER_TRANSACTION_FREE, DEVSTAT_ARG_LD },
136 { DSM_BUSY_PCT, DEVSTAT_ARG_LD },
137 { DSM_QUEUE_LENGTH, DEVSTAT_ARG_UINT64 },
138 { DSM_TOTAL_DURATION, DEVSTAT_ARG_LD },
139 { DSM_TOTAL_DURATION_READ, DEVSTAT_ARG_LD },
140 { DSM_TOTAL_DURATION_WRITE, DEVSTAT_ARG_LD },
141 { DSM_TOTAL_DURATION_FREE, DEVSTAT_ARG_LD },
142 { DSM_TOTAL_DURATION_OTHER, DEVSTAT_ARG_LD },
143 { DSM_TOTAL_BUSY_TIME, DEVSTAT_ARG_LD },
146 static const char *namelist[] = {
149 #define X_GENERATION 1
150 "_devstat_generation",
153 #define X_DEVICE_STATQ 3
155 #define X_TIME_UPTIME 4
161 * Local function declarations.
163 static int compare_select(const void *arg1, const void *arg2);
164 static int readkmem(kvm_t *kd, unsigned long addr, void *buf, size_t nbytes);
165 static int readkmem_nl(kvm_t *kd, const char *name, void *buf, size_t nbytes);
166 static char *get_devstat_kvm(kvm_t *kd);
168 #define KREADNL(kd, var, val) \
169 readkmem_nl(kd, namelist[var], &val, sizeof(val))
172 devstat_getnumdevs(kvm_t *kd)
177 numdevsize = sizeof(int);
180 * Find out how many devices we have in the system.
183 if (sysctlbyname("kern.devstat.numdevs", &numdevs,
184 &numdevsize, NULL, 0) == -1) {
185 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
186 "%s: error getting number of devices\n"
187 "%s: %s", __func__, __func__,
194 if (KREADNL(kd, X_NUMDEVS, numdevs) == -1)
202 * This is an easy way to get the generation number, but the generation is
203 * supplied in a more atmoic manner by the kern.devstat.all sysctl.
204 * Because this generation sysctl is separate from the statistics sysctl,
205 * the device list and the generation could change between the time that
206 * this function is called and the device list is retrieved.
209 devstat_getgeneration(kvm_t *kd)
214 gensize = sizeof(long);
217 * Get the current generation number.
220 if (sysctlbyname("kern.devstat.generation", &generation,
221 &gensize, NULL, 0) == -1) {
222 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
223 "%s: error getting devstat generation\n%s: %s",
224 __func__, __func__, strerror(errno));
229 if (KREADNL(kd, X_GENERATION, generation) == -1)
237 * Get the current devstat version. The return value of this function
238 * should be compared with DEVSTAT_VERSION, which is defined in
239 * sys/devicestat.h. This will enable userland programs to determine
240 * whether they are out of sync with the kernel.
243 devstat_getversion(kvm_t *kd)
248 versize = sizeof(int);
251 * Get the current devstat version.
254 if (sysctlbyname("kern.devstat.version", &version, &versize,
256 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
257 "%s: error getting devstat version\n%s: %s",
258 __func__, __func__, strerror(errno));
263 if (KREADNL(kd, X_VERSION, version) == -1)
271 * Check the devstat version we know about against the devstat version the
272 * kernel knows about. If they don't match, print an error into the
273 * devstat error buffer, and return -1. If they match, return 0.
276 devstat_checkversion(kvm_t *kd)
278 int buflen, res, retval = 0, version;
280 version = devstat_getversion(kd);
282 if (version != DEVSTAT_VERSION) {
284 * If getversion() returns an error (i.e. -1), then it
285 * has printed an error message in the buffer. Therefore,
286 * we need to add a \n to the end of that message before we
287 * print our own message in the buffer.
290 buflen = strlen(devstat_errbuf);
294 res = snprintf(devstat_errbuf + buflen,
295 DEVSTAT_ERRBUF_SIZE - buflen,
296 "%s%s: userland devstat version %d is not "
297 "the same as the kernel\n%s: devstat "
298 "version %d\n", version == -1 ? "\n" : "",
299 __func__, DEVSTAT_VERSION, __func__, version);
302 devstat_errbuf[buflen] = '\0';
304 buflen = strlen(devstat_errbuf);
305 if (version < DEVSTAT_VERSION)
306 res = snprintf(devstat_errbuf + buflen,
307 DEVSTAT_ERRBUF_SIZE - buflen,
308 "%s: libdevstat newer than kernel\n",
311 res = snprintf(devstat_errbuf + buflen,
312 DEVSTAT_ERRBUF_SIZE - buflen,
313 "%s: kernel newer than libdevstat\n",
317 devstat_errbuf[buflen] = '\0';
326 * Get the current list of devices and statistics, and the current
331 * 0 -- device list is unchanged
332 * 1 -- device list has changed
335 devstat_getdevs(kvm_t *kd, struct statinfo *stats)
341 struct devinfo *dinfo;
344 dinfo = stats->dinfo;
347 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
348 "%s: stats->dinfo was NULL", __func__);
352 oldgeneration = dinfo->generation;
355 clock_gettime(CLOCK_MONOTONIC, &ts);
356 stats->snap_time = ts.tv_sec + ts.tv_nsec * 1e-9;
358 /* If this is our first time through, mem_ptr will be null. */
359 if (dinfo->mem_ptr == NULL) {
361 * Get the number of devices. If it's negative, it's an
362 * error. Don't bother setting the error string, since
363 * getnumdevs() has already done that for us.
365 if ((dinfo->numdevs = devstat_getnumdevs(kd)) < 0)
369 * The kern.devstat.all sysctl returns the current
370 * generation number, as well as all the devices.
371 * So we need four bytes more.
373 dssize = (dinfo->numdevs * sizeof(struct devstat)) +
375 dinfo->mem_ptr = (u_int8_t *)malloc(dssize);
376 if (dinfo->mem_ptr == NULL) {
377 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
378 "%s: Cannot allocate memory for mem_ptr element",
383 dssize = (dinfo->numdevs * sizeof(struct devstat)) +
387 * Request all of the devices. We only really allow for one
388 * ENOMEM failure. It would, of course, be possible to just go
389 * in a loop and keep reallocing the device structure until we
390 * don't get ENOMEM back. I'm not sure it's worth it, though.
391 * If devices are being added to the system that quickly, maybe
392 * the user can just wait until all devices are added.
395 error = sysctlbyname("kern.devstat.all",
398 if (error != -1 || errno != EBUSY)
403 * If we get ENOMEM back, that means that there are
404 * more devices now, so we need to allocate more
405 * space for the device array.
407 if (errno == ENOMEM) {
409 * No need to set the error string here,
410 * devstat_getnumdevs() will do that if it fails.
412 if ((dinfo->numdevs = devstat_getnumdevs(kd)) < 0)
415 dssize = (dinfo->numdevs *
416 sizeof(struct devstat)) + sizeof(long);
417 dinfo->mem_ptr = (u_int8_t *)
418 realloc(dinfo->mem_ptr, dssize);
419 if ((error = sysctlbyname("kern.devstat.all",
420 dinfo->mem_ptr, &dssize, NULL, 0)) == -1) {
421 snprintf(devstat_errbuf,
422 sizeof(devstat_errbuf),
423 "%s: error getting device "
424 "stats\n%s: %s", __func__,
425 __func__, strerror(errno));
429 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
430 "%s: error getting device stats\n"
431 "%s: %s", __func__, __func__,
438 if (KREADNL(kd, X_TIME_UPTIME, ts.tv_sec) == -1)
441 stats->snap_time = ts.tv_sec;
444 * This is of course non-atomic, but since we are working
445 * on a core dump, the generation is unlikely to change
447 if ((dinfo->numdevs = devstat_getnumdevs(kd)) == -1)
449 if ((dinfo->mem_ptr = (u_int8_t *)get_devstat_kvm(kd)) == NULL)
453 * The sysctl spits out the generation as the first four bytes,
454 * then all of the device statistics structures.
456 dinfo->generation = *(long *)dinfo->mem_ptr;
459 * If the generation has changed, and if the current number of
460 * devices is not the same as the number of devices recorded in the
461 * devinfo structure, it is likely that the device list has shrunk.
462 * The reason that it is likely that the device list has shrunk in
463 * this case is that if the device list has grown, the sysctl above
464 * will return an ENOMEM error, and we will reset the number of
465 * devices and reallocate the device array. If the second sysctl
466 * fails, we will return an error and therefore never get to this
467 * point. If the device list has shrunk, the sysctl will not
468 * return an error since we have more space allocated than is
469 * necessary. So, in the shrinkage case, we catch it here and
470 * reallocate the array so that we don't use any more space than is
473 if (oldgeneration != dinfo->generation) {
474 if (devstat_getnumdevs(kd) != dinfo->numdevs) {
475 if ((dinfo->numdevs = devstat_getnumdevs(kd)) < 0)
477 dssize = (dinfo->numdevs * sizeof(struct devstat)) +
479 dinfo->mem_ptr = (u_int8_t *)realloc(dinfo->mem_ptr,
485 dinfo->devices = (struct devstat *)(dinfo->mem_ptr + sizeof(long));
493 * Devices are selected/deselected based upon the following criteria:
494 * - devices specified by the user on the command line
495 * - devices matching any device type expressions given on the command line
496 * - devices with the highest I/O, if 'top' mode is enabled
497 * - the first n unselected devices in the device list, if maxshowdevs
498 * devices haven't already been selected and if the user has not
499 * specified any devices on the command line and if we're in "add" mode.
502 * - device selection list (dev_select)
503 * - current number of devices selected (num_selected)
504 * - total number of devices in the selection list (num_selections)
505 * - devstat generation as of the last time selectdevs() was called
506 * (select_generation)
507 * - current devstat generation (current_generation)
508 * - current list of devices and statistics (devices)
509 * - number of devices in the current device list (numdevs)
510 * - compiled version of the command line device type arguments (matches)
511 * - This is optional. If the number of devices is 0, this will be ignored.
512 * - The matching code pays attention to the current selection mode. So
513 * if you pass in a matching expression, it will be evaluated based
514 * upon the selection mode that is passed in. See below for details.
515 * - number of device type matching expressions (num_matches)
516 * - Set to 0 to disable the matching code.
517 * - list of devices specified on the command line by the user (dev_selections)
518 * - number of devices selected on the command line by the user
519 * (num_dev_selections)
520 * - Our selection mode. There are four different selection modes:
521 * - add mode. (DS_SELECT_ADD) Any devices matching devices explicitly
522 * selected by the user or devices matching a pattern given by the
523 * user will be selected in addition to devices that are already
524 * selected. Additional devices will be selected, up to maxshowdevs
526 * - only mode. (DS_SELECT_ONLY) Only devices matching devices
527 * explicitly given by the user or devices matching a pattern
528 * given by the user will be selected. No other devices will be
530 * - addonly mode. (DS_SELECT_ADDONLY) This is similar to add and
531 * only. Basically, this will not de-select any devices that are
532 * current selected, as only mode would, but it will also not
533 * gratuitously select up to maxshowdevs devices as add mode would.
534 * - remove mode. (DS_SELECT_REMOVE) Any devices matching devices
535 * explicitly selected by the user or devices matching a pattern
536 * given by the user will be de-selected.
537 * - maximum number of devices we can select (maxshowdevs)
538 * - flag indicating whether or not we're in 'top' mode (perf_select)
541 * - the device selection list may be modified and passed back out
542 * - the number of devices selected and the total number of items in the
543 * device selection list may be changed
544 * - the selection generation may be changed to match the current generation
548 * 0 -- selected devices are unchanged
549 * 1 -- selected devices changed
552 devstat_selectdevs(struct device_selection **dev_select, int *num_selected,
553 int *num_selections, long *select_generation,
554 long current_generation, struct devstat *devices,
555 int numdevs, struct devstat_match *matches, int num_matches,
556 char **dev_selections, int num_dev_selections,
557 devstat_select_mode select_mode, int maxshowdevs,
561 int init_selections = 0, init_selected_var = 0;
562 struct device_selection *old_dev_select = NULL;
563 int old_num_selections = 0, old_num_selected;
564 int selection_number = 0;
565 int changed = 0, found = 0;
567 if ((dev_select == NULL) || (devices == NULL) || (numdevs < 0))
571 * We always want to make sure that we have as many dev_select
572 * entries as there are devices.
575 * In this case, we haven't selected devices before.
577 if (*dev_select == NULL) {
578 *dev_select = (struct device_selection *)malloc(numdevs *
579 sizeof(struct device_selection));
580 *select_generation = current_generation;
584 * In this case, we have selected devices before, but the device
585 * list has changed since we last selected devices, so we need to
586 * either enlarge or reduce the size of the device selection list.
588 } else if (*num_selections != numdevs) {
589 *dev_select = (struct device_selection *)reallocf(*dev_select,
590 numdevs * sizeof(struct device_selection));
591 *select_generation = current_generation;
594 * In this case, we've selected devices before, and the selection
595 * list is the same size as it was the last time, but the device
598 } else if (*select_generation < current_generation) {
599 *select_generation = current_generation;
603 if (*dev_select == NULL) {
604 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
605 "%s: Cannot (re)allocate memory for dev_select argument",
611 * If we're in "only" mode, we want to clear out the selected
612 * variable since we're going to select exactly what the user wants
615 if (select_mode == DS_SELECT_ONLY)
616 init_selected_var = 1;
619 * In all cases, we want to back up the number of selected devices.
620 * It is a quick and accurate way to determine whether the selected
621 * devices have changed.
623 old_num_selected = *num_selected;
626 * We want to make a backup of the current selection list if
627 * the list of devices has changed, or if we're in performance
628 * selection mode. In both cases, we don't want to make a backup
629 * if we already know for sure that the list will be different.
630 * This is certainly the case if this is our first time through the
633 if (((init_selected_var != 0) || (init_selections != 0)
634 || (perf_select != 0)) && (changed == 0)){
635 old_dev_select = (struct device_selection *)malloc(
636 *num_selections * sizeof(struct device_selection));
637 if (old_dev_select == NULL) {
638 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
639 "%s: Cannot allocate memory for selection list backup",
643 old_num_selections = *num_selections;
644 bcopy(*dev_select, old_dev_select,
645 sizeof(struct device_selection) * *num_selections);
648 if (init_selections != 0) {
649 bzero(*dev_select, sizeof(struct device_selection) * numdevs);
651 for (i = 0; i < numdevs; i++) {
652 (*dev_select)[i].device_number =
653 devices[i].device_number;
654 strncpy((*dev_select)[i].device_name,
655 devices[i].device_name,
657 (*dev_select)[i].device_name[DEVSTAT_NAME_LEN - 1]='\0';
658 (*dev_select)[i].unit_number = devices[i].unit_number;
659 (*dev_select)[i].position = i;
661 *num_selections = numdevs;
662 } else if (init_selected_var != 0) {
663 for (i = 0; i < numdevs; i++)
664 (*dev_select)[i].selected = 0;
667 /* we haven't gotten around to selecting anything yet.. */
668 if ((select_mode == DS_SELECT_ONLY) || (init_selections != 0)
669 || (init_selected_var != 0))
673 * Look through any devices the user specified on the command line
674 * and see if they match known devices. If so, select them.
676 for (i = 0; (i < *num_selections) && (num_dev_selections > 0); i++) {
679 snprintf(tmpstr, sizeof(tmpstr), "%s%d",
680 (*dev_select)[i].device_name,
681 (*dev_select)[i].unit_number);
682 for (j = 0; j < num_dev_selections; j++) {
683 if (strcmp(tmpstr, dev_selections[j]) == 0) {
685 * Here we do different things based on the
686 * mode we're in. If we're in add or
687 * addonly mode, we only select this device
688 * if it hasn't already been selected.
689 * Otherwise, we would be unnecessarily
690 * changing the selection order and
691 * incrementing the selection count. If
692 * we're in only mode, we unconditionally
693 * select this device, since in only mode
694 * any previous selections are erased and
695 * manually specified devices are the first
696 * ones to be selected. If we're in remove
697 * mode, we de-select the specified device and
698 * decrement the selection count.
700 switch(select_mode) {
702 case DS_SELECT_ADDONLY:
703 if ((*dev_select)[i].selected)
707 (*dev_select)[i].selected =
711 case DS_SELECT_REMOVE:
712 (*dev_select)[i].selected = 0;
715 * This isn't passed back out, we
716 * just use it to keep track of
717 * how many devices we've removed.
719 num_dev_selections--;
728 * Go through the user's device type expressions and select devices
729 * accordingly. We only do this if the number of devices already
730 * selected is less than the maximum number we can show.
732 for (i = 0; (i < num_matches) && (*num_selected < maxshowdevs); i++) {
733 /* We should probably indicate some error here */
734 if ((matches[i].match_fields == DEVSTAT_MATCH_NONE)
735 || (matches[i].num_match_categories <= 0))
738 for (j = 0; j < numdevs; j++) {
739 int num_match_categories;
741 num_match_categories = matches[i].num_match_categories;
744 * Determine whether or not the current device
745 * matches the given matching expression. This if
746 * statement consists of three components:
747 * - the device type check
748 * - the device interface check
749 * - the passthrough check
750 * If a the matching test is successful, it
751 * decrements the number of matching categories,
752 * and if we've reached the last element that
753 * needed to be matched, the if statement succeeds.
756 if ((((matches[i].match_fields & DEVSTAT_MATCH_TYPE)!=0)
757 && ((devices[j].device_type & DEVSTAT_TYPE_MASK) ==
758 (matches[i].device_type & DEVSTAT_TYPE_MASK))
759 &&(((matches[i].match_fields & DEVSTAT_MATCH_PASS)!=0)
760 || (((matches[i].match_fields &
761 DEVSTAT_MATCH_PASS) == 0)
762 && ((devices[j].device_type &
763 DEVSTAT_TYPE_PASS) == 0)))
764 && (--num_match_categories == 0))
765 || (((matches[i].match_fields & DEVSTAT_MATCH_IF) != 0)
766 && ((devices[j].device_type & DEVSTAT_TYPE_IF_MASK) ==
767 (matches[i].device_type & DEVSTAT_TYPE_IF_MASK))
768 &&(((matches[i].match_fields & DEVSTAT_MATCH_PASS)!=0)
769 || (((matches[i].match_fields &
770 DEVSTAT_MATCH_PASS) == 0)
771 && ((devices[j].device_type &
772 DEVSTAT_TYPE_PASS) == 0)))
773 && (--num_match_categories == 0))
774 || (((matches[i].match_fields & DEVSTAT_MATCH_PASS)!=0)
775 && ((devices[j].device_type & DEVSTAT_TYPE_PASS) != 0)
776 && (--num_match_categories == 0))) {
779 * This is probably a non-optimal solution
780 * to the problem that the devices in the
781 * device list will not be in the same
782 * order as the devices in the selection
785 for (k = 0; k < numdevs; k++) {
786 if ((*dev_select)[k].position == j) {
793 * There shouldn't be a case where a device
794 * in the device list is not in the
795 * selection list...but it could happen.
798 fprintf(stderr, "selectdevs: couldn't"
799 " find %s%d in selection "
801 devices[j].device_name,
802 devices[j].unit_number);
807 * We do different things based upon the
808 * mode we're in. If we're in add or only
809 * mode, we go ahead and select this device
810 * if it hasn't already been selected. If
811 * it has already been selected, we leave
812 * it alone so we don't mess up the
813 * selection ordering. Manually specified
814 * devices have already been selected, and
815 * they have higher priority than pattern
816 * matched devices. If we're in remove
817 * mode, we de-select the given device and
818 * decrement the selected count.
820 switch(select_mode) {
822 case DS_SELECT_ADDONLY:
824 if ((*dev_select)[k].selected != 0)
826 (*dev_select)[k].selected =
830 case DS_SELECT_REMOVE:
831 (*dev_select)[k].selected = 0;
840 * Here we implement "top" mode. Devices are sorted in the
841 * selection array based on two criteria: whether or not they are
842 * selected (not selection number, just the fact that they are
843 * selected!) and the number of bytes in the "bytes" field of the
844 * selection structure. The bytes field generally must be kept up
845 * by the user. In the future, it may be maintained by library
846 * functions, but for now the user has to do the work.
848 * At first glance, it may seem wrong that we don't go through and
849 * select every device in the case where the user hasn't specified
850 * any devices or patterns. In fact, though, it won't make any
851 * difference in the device sorting. In that particular case (i.e.
852 * when we're in "add" or "only" mode, and the user hasn't
853 * specified anything) the first time through no devices will be
854 * selected, so the only criterion used to sort them will be their
855 * performance. The second time through, and every time thereafter,
856 * all devices will be selected, so again selection won't matter.
858 if (perf_select != 0) {
860 /* Sort the device array by throughput */
861 qsort(*dev_select, *num_selections,
862 sizeof(struct device_selection),
865 if (*num_selected == 0) {
867 * Here we select every device in the array, if it
868 * isn't already selected. Because the 'selected'
869 * variable in the selection array entries contains
870 * the selection order, the devstats routine can show
871 * the devices that were selected first.
873 for (i = 0; i < *num_selections; i++) {
874 if ((*dev_select)[i].selected == 0) {
875 (*dev_select)[i].selected =
881 selection_number = 0;
882 for (i = 0; i < *num_selections; i++) {
883 if ((*dev_select)[i].selected != 0) {
884 (*dev_select)[i].selected =
892 * If we're in the "add" selection mode and if we haven't already
893 * selected maxshowdevs number of devices, go through the array and
894 * select any unselected devices. If we're in "only" mode, we
895 * obviously don't want to select anything other than what the user
896 * specifies. If we're in "remove" mode, it probably isn't a good
897 * idea to go through and select any more devices, since we might
898 * end up selecting something that the user wants removed. Through
899 * more complicated logic, we could actually figure this out, but
900 * that would probably require combining this loop with the various
901 * selections loops above.
903 if ((select_mode == DS_SELECT_ADD) && (*num_selected < maxshowdevs)) {
904 for (i = 0; i < *num_selections; i++)
905 if ((*dev_select)[i].selected == 0) {
906 (*dev_select)[i].selected = ++selection_number;
912 * Look at the number of devices that have been selected. If it
913 * has changed, set the changed variable. Otherwise, if we've
914 * made a backup of the selection list, compare it to the current
915 * selection list to see if the selected devices have changed.
917 if ((changed == 0) && (old_num_selected != *num_selected))
919 else if ((changed == 0) && (old_dev_select != NULL)) {
921 * Now we go through the selection list and we look at
922 * it three different ways.
924 for (i = 0; (i < *num_selections) && (changed == 0) &&
925 (i < old_num_selections); i++) {
927 * If the device at index i in both the new and old
928 * selection arrays has the same device number and
929 * selection status, it hasn't changed. We
930 * continue on to the next index.
932 if (((*dev_select)[i].device_number ==
933 old_dev_select[i].device_number)
934 && ((*dev_select)[i].selected ==
935 old_dev_select[i].selected))
939 * Now, if we're still going through the if
940 * statement, the above test wasn't true. So we
941 * check here to see if the device at index i in
942 * the current array is the same as the device at
943 * index i in the old array. If it is, that means
944 * that its selection number has changed. Set
945 * changed to 1 and exit the loop.
947 else if ((*dev_select)[i].device_number ==
948 old_dev_select[i].device_number) {
953 * If we get here, then the device at index i in
954 * the current array isn't the same device as the
955 * device at index i in the old array.
961 * Search through the old selection array
962 * looking for a device with the same
963 * device number as the device at index i
964 * in the current array. If the selection
965 * status is the same, then we mark it as
966 * found. If the selection status isn't
967 * the same, we break out of the loop.
968 * Since found isn't set, changed will be
971 for (j = 0; j < old_num_selections; j++) {
972 if (((*dev_select)[i].device_number ==
973 old_dev_select[j].device_number)
974 && ((*dev_select)[i].selected ==
975 old_dev_select[j].selected)){
979 else if ((*dev_select)[i].device_number
980 == old_dev_select[j].device_number)
988 if (old_dev_select != NULL)
989 free(old_dev_select);
995 * Comparison routine for qsort() above. Note that the comparison here is
996 * backwards -- generally, it should return a value to indicate whether
997 * arg1 is <, =, or > arg2. Instead, it returns the opposite. The reason
998 * it returns the opposite is so that the selection array will be sorted in
999 * order of decreasing performance. We sort on two parameters. The first
1000 * sort key is whether or not one or the other of the devices in question
1001 * has been selected. If one of them has, and the other one has not, the
1002 * selected device is automatically more important than the unselected
1003 * device. If neither device is selected, we judge the devices based upon
1007 compare_select(const void *arg1, const void *arg2)
1009 if ((((const struct device_selection *)arg1)->selected)
1010 && (((const struct device_selection *)arg2)->selected == 0))
1012 else if ((((const struct device_selection *)arg1)->selected == 0)
1013 && (((const struct device_selection *)arg2)->selected))
1015 else if (((const struct device_selection *)arg2)->bytes <
1016 ((const struct device_selection *)arg1)->bytes)
1018 else if (((const struct device_selection *)arg2)->bytes >
1019 ((const struct device_selection *)arg1)->bytes)
1026 * Take a string with the general format "arg1,arg2,arg3", and build a
1027 * device matching expression from it.
1030 devstat_buildmatch(char *match_str, struct devstat_match **matches,
1038 /* We can't do much without a string to parse */
1039 if (match_str == NULL) {
1040 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
1041 "%s: no match expression", __func__);
1046 * Break the (comma delimited) input string out into separate strings.
1048 for (tempstr = tstr, num_args = 0;
1049 (*tempstr = strsep(&match_str, ",")) != NULL && (num_args < 5);)
1050 if (**tempstr != '\0') {
1052 if (++tempstr >= &tstr[5])
1056 /* The user gave us too many type arguments */
1058 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
1059 "%s: too many type arguments", __func__);
1063 if (*num_matches == 0)
1066 *matches = (struct devstat_match *)reallocf(*matches,
1067 sizeof(struct devstat_match) * (*num_matches + 1));
1069 if (*matches == NULL) {
1070 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
1071 "%s: Cannot allocate memory for matches list", __func__);
1075 /* Make sure the current entry is clear */
1076 bzero(&matches[0][*num_matches], sizeof(struct devstat_match));
1079 * Step through the arguments the user gave us and build a device
1080 * matching expression from them.
1082 for (i = 0; i < num_args; i++) {
1083 char *tempstr2, *tempstr3;
1086 * Get rid of leading white space.
1089 while (isspace(*tempstr2) && (*tempstr2 != '\0'))
1093 * Get rid of trailing white space.
1095 tempstr3 = &tempstr2[strlen(tempstr2) - 1];
1097 while ((*tempstr3 != '\0') && (tempstr3 > tempstr2)
1098 && (isspace(*tempstr3))) {
1104 * Go through the match table comparing the user's
1105 * arguments to known device types, interfaces, etc.
1107 for (j = 0; match_table[j].match_str != NULL; j++) {
1109 * We do case-insensitive matching, in case someone
1110 * wants to enter "SCSI" instead of "scsi" or
1111 * something like that. Only compare as many
1112 * characters as are in the string in the match
1113 * table. This should help if someone tries to use
1114 * a super-long match expression.
1116 if (strncasecmp(tempstr2, match_table[j].match_str,
1117 strlen(match_table[j].match_str)) == 0) {
1119 * Make sure the user hasn't specified two
1120 * items of the same type, like "da" and
1121 * "cd". One device cannot be both.
1123 if (((*matches)[*num_matches].match_fields &
1124 match_table[j].match_field) != 0) {
1125 snprintf(devstat_errbuf,
1126 sizeof(devstat_errbuf),
1127 "%s: cannot have more than "
1128 "one match item in a single "
1129 "category", __func__);
1133 * If we've gotten this far, we have a
1134 * winner. Set the appropriate fields in
1137 (*matches)[*num_matches].match_fields |=
1138 match_table[j].match_field;
1139 (*matches)[*num_matches].device_type |=
1140 match_table[j].type;
1141 (*matches)[*num_matches].num_match_categories++;
1146 * We should have found a match in the above for loop. If
1147 * not, that means the user entered an invalid device type
1150 if ((*matches)[*num_matches].num_match_categories != (i + 1)) {
1151 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
1152 "%s: unknown match item \"%s\"", __func__,
1164 * Compute a number of device statistics. Only one field is mandatory, and
1165 * that is "current". Everything else is optional. The caller passes in
1166 * pointers to variables to hold the various statistics he desires. If he
1167 * doesn't want a particular staistic, he should pass in a NULL pointer.
1173 compute_stats(struct devstat *current, struct devstat *previous,
1174 long double etime, u_int64_t *total_bytes,
1175 u_int64_t *total_transfers, u_int64_t *total_blocks,
1176 long double *kb_per_transfer, long double *transfers_per_second,
1177 long double *mb_per_second, long double *blocks_per_second,
1178 long double *ms_per_transaction)
1180 return(devstat_compute_statistics(current, previous, etime,
1181 total_bytes ? DSM_TOTAL_BYTES : DSM_SKIP,
1183 total_transfers ? DSM_TOTAL_TRANSFERS : DSM_SKIP,
1185 total_blocks ? DSM_TOTAL_BLOCKS : DSM_SKIP,
1187 kb_per_transfer ? DSM_KB_PER_TRANSFER : DSM_SKIP,
1189 transfers_per_second ? DSM_TRANSFERS_PER_SECOND : DSM_SKIP,
1190 transfers_per_second,
1191 mb_per_second ? DSM_MB_PER_SECOND : DSM_SKIP,
1193 blocks_per_second ? DSM_BLOCKS_PER_SECOND : DSM_SKIP,
1195 ms_per_transaction ? DSM_MS_PER_TRANSACTION : DSM_SKIP,
1201 /* This is 1/2^64 */
1202 #define BINTIME_SCALE 5.42101086242752217003726400434970855712890625e-20
1205 devstat_compute_etime(struct bintime *cur_time, struct bintime *prev_time)
1209 etime = cur_time->sec;
1210 etime += cur_time->frac * BINTIME_SCALE;
1211 if (prev_time != NULL) {
1212 etime -= prev_time->sec;
1213 etime -= prev_time->frac * BINTIME_SCALE;
1218 #define DELTA(field, index) \
1219 (current->field[(index)] - (previous ? previous->field[(index)] : 0))
1221 #define DELTA_T(field) \
1222 devstat_compute_etime(¤t->field, \
1223 (previous ? &previous->field : NULL))
1226 devstat_compute_statistics(struct devstat *current, struct devstat *previous,
1227 long double etime, ...)
1229 u_int64_t totalbytes, totalbytesread, totalbyteswrite, totalbytesfree;
1230 u_int64_t totaltransfers, totaltransfersread, totaltransferswrite;
1231 u_int64_t totaltransfersother, totalblocks, totalblocksread;
1232 u_int64_t totalblockswrite, totaltransfersfree, totalblocksfree;
1233 long double totalduration, totaldurationread, totaldurationwrite;
1234 long double totaldurationfree, totaldurationother;
1236 devstat_metric metric;
1238 long double *destld;
1244 * current is the only mandatory field.
1246 if (current == NULL) {
1247 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
1248 "%s: current stats structure was NULL", __func__);
1252 totalbytesread = DELTA(bytes, DEVSTAT_READ);
1253 totalbyteswrite = DELTA(bytes, DEVSTAT_WRITE);
1254 totalbytesfree = DELTA(bytes, DEVSTAT_FREE);
1255 totalbytes = totalbytesread + totalbyteswrite + totalbytesfree;
1257 totaltransfersread = DELTA(operations, DEVSTAT_READ);
1258 totaltransferswrite = DELTA(operations, DEVSTAT_WRITE);
1259 totaltransfersother = DELTA(operations, DEVSTAT_NO_DATA);
1260 totaltransfersfree = DELTA(operations, DEVSTAT_FREE);
1261 totaltransfers = totaltransfersread + totaltransferswrite +
1262 totaltransfersother + totaltransfersfree;
1264 totalblocks = totalbytes;
1265 totalblocksread = totalbytesread;
1266 totalblockswrite = totalbyteswrite;
1267 totalblocksfree = totalbytesfree;
1269 if (current->block_size > 0) {
1270 totalblocks /= current->block_size;
1271 totalblocksread /= current->block_size;
1272 totalblockswrite /= current->block_size;
1273 totalblocksfree /= current->block_size;
1276 totalblocksread /= 512;
1277 totalblockswrite /= 512;
1278 totalblocksfree /= 512;
1281 totaldurationread = DELTA_T(duration[DEVSTAT_READ]);
1282 totaldurationwrite = DELTA_T(duration[DEVSTAT_WRITE]);
1283 totaldurationfree = DELTA_T(duration[DEVSTAT_FREE]);
1284 totaldurationother = DELTA_T(duration[DEVSTAT_NO_DATA]);
1285 totalduration = totaldurationread + totaldurationwrite +
1286 totaldurationfree + totaldurationother;
1288 va_start(ap, etime);
1290 while ((metric = (devstat_metric)va_arg(ap, devstat_metric)) != 0) {
1292 if (metric == DSM_NONE)
1295 if (metric >= DSM_MAX) {
1296 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
1297 "%s: metric %d is out of range", __func__,
1303 switch (devstat_arg_list[metric].argtype) {
1304 case DEVSTAT_ARG_UINT64:
1305 destu64 = (u_int64_t *)va_arg(ap, u_int64_t *);
1307 case DEVSTAT_ARG_LD:
1308 destld = (long double *)va_arg(ap, long double *);
1310 case DEVSTAT_ARG_SKIP:
1311 destld = (long double *)va_arg(ap, long double *);
1316 break; /* NOTREACHED */
1319 if (devstat_arg_list[metric].argtype == DEVSTAT_ARG_SKIP)
1323 case DSM_TOTAL_BYTES:
1324 *destu64 = totalbytes;
1326 case DSM_TOTAL_BYTES_READ:
1327 *destu64 = totalbytesread;
1329 case DSM_TOTAL_BYTES_WRITE:
1330 *destu64 = totalbyteswrite;
1332 case DSM_TOTAL_BYTES_FREE:
1333 *destu64 = totalbytesfree;
1335 case DSM_TOTAL_TRANSFERS:
1336 *destu64 = totaltransfers;
1338 case DSM_TOTAL_TRANSFERS_READ:
1339 *destu64 = totaltransfersread;
1341 case DSM_TOTAL_TRANSFERS_WRITE:
1342 *destu64 = totaltransferswrite;
1344 case DSM_TOTAL_TRANSFERS_FREE:
1345 *destu64 = totaltransfersfree;
1347 case DSM_TOTAL_TRANSFERS_OTHER:
1348 *destu64 = totaltransfersother;
1350 case DSM_TOTAL_BLOCKS:
1351 *destu64 = totalblocks;
1353 case DSM_TOTAL_BLOCKS_READ:
1354 *destu64 = totalblocksread;
1356 case DSM_TOTAL_BLOCKS_WRITE:
1357 *destu64 = totalblockswrite;
1359 case DSM_TOTAL_BLOCKS_FREE:
1360 *destu64 = totalblocksfree;
1362 case DSM_KB_PER_TRANSFER:
1363 *destld = totalbytes;
1365 if (totaltransfers > 0)
1366 *destld /= totaltransfers;
1370 case DSM_KB_PER_TRANSFER_READ:
1371 *destld = totalbytesread;
1373 if (totaltransfersread > 0)
1374 *destld /= totaltransfersread;
1378 case DSM_KB_PER_TRANSFER_WRITE:
1379 *destld = totalbyteswrite;
1381 if (totaltransferswrite > 0)
1382 *destld /= totaltransferswrite;
1386 case DSM_KB_PER_TRANSFER_FREE:
1387 *destld = totalbytesfree;
1389 if (totaltransfersfree > 0)
1390 *destld /= totaltransfersfree;
1394 case DSM_TRANSFERS_PER_SECOND:
1396 *destld = totaltransfers;
1401 case DSM_TRANSFERS_PER_SECOND_READ:
1403 *destld = totaltransfersread;
1408 case DSM_TRANSFERS_PER_SECOND_WRITE:
1410 *destld = totaltransferswrite;
1415 case DSM_TRANSFERS_PER_SECOND_FREE:
1417 *destld = totaltransfersfree;
1422 case DSM_TRANSFERS_PER_SECOND_OTHER:
1424 *destld = totaltransfersother;
1429 case DSM_MB_PER_SECOND:
1430 *destld = totalbytes;
1431 *destld /= 1024 * 1024;
1437 case DSM_MB_PER_SECOND_READ:
1438 *destld = totalbytesread;
1439 *destld /= 1024 * 1024;
1445 case DSM_MB_PER_SECOND_WRITE:
1446 *destld = totalbyteswrite;
1447 *destld /= 1024 * 1024;
1453 case DSM_MB_PER_SECOND_FREE:
1454 *destld = totalbytesfree;
1455 *destld /= 1024 * 1024;
1461 case DSM_BLOCKS_PER_SECOND:
1462 *destld = totalblocks;
1468 case DSM_BLOCKS_PER_SECOND_READ:
1469 *destld = totalblocksread;
1475 case DSM_BLOCKS_PER_SECOND_WRITE:
1476 *destld = totalblockswrite;
1482 case DSM_BLOCKS_PER_SECOND_FREE:
1483 *destld = totalblocksfree;
1490 * Some devstat callers update the duration and some don't.
1491 * So this will only be accurate if they provide the
1494 case DSM_MS_PER_TRANSACTION:
1495 if (totaltransfers > 0) {
1496 *destld = totalduration;
1497 *destld /= totaltransfers;
1502 case DSM_MS_PER_TRANSACTION_READ:
1503 if (totaltransfersread > 0) {
1504 *destld = totaldurationread;
1505 *destld /= totaltransfersread;
1510 case DSM_MS_PER_TRANSACTION_WRITE:
1511 if (totaltransferswrite > 0) {
1512 *destld = totaldurationwrite;
1513 *destld /= totaltransferswrite;
1518 case DSM_MS_PER_TRANSACTION_FREE:
1519 if (totaltransfersfree > 0) {
1520 *destld = totaldurationfree;
1521 *destld /= totaltransfersfree;
1526 case DSM_MS_PER_TRANSACTION_OTHER:
1527 if (totaltransfersother > 0) {
1528 *destld = totaldurationother;
1529 *destld /= totaltransfersother;
1535 *destld = DELTA_T(busy_time);
1543 case DSM_QUEUE_LENGTH:
1544 *destu64 = current->start_count - current->end_count;
1546 case DSM_TOTAL_DURATION:
1547 *destld = totalduration;
1549 case DSM_TOTAL_DURATION_READ:
1550 *destld = totaldurationread;
1552 case DSM_TOTAL_DURATION_WRITE:
1553 *destld = totaldurationwrite;
1555 case DSM_TOTAL_DURATION_FREE:
1556 *destld = totaldurationfree;
1558 case DSM_TOTAL_DURATION_OTHER:
1559 *destld = totaldurationother;
1561 case DSM_TOTAL_BUSY_TIME:
1562 *destld = DELTA_T(busy_time);
1565 * XXX: comment out the default block to see if any case's are missing.
1570 * This shouldn't happen, since we should have
1571 * caught any out of range metrics at the top of
1574 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
1575 "%s: unknown metric %d", __func__, metric);
1578 break; /* NOTREACHED */
1590 readkmem(kvm_t *kd, unsigned long addr, void *buf, size_t nbytes)
1593 if (kvm_read(kd, addr, buf, nbytes) == -1) {
1594 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
1595 "%s: error reading value (kvm_read): %s", __func__,
1603 readkmem_nl(kvm_t *kd, const char *name, void *buf, size_t nbytes)
1607 nl[0].n_name = (char *)name;
1608 nl[1].n_name = NULL;
1610 if (kvm_nlist(kd, nl) == -1) {
1611 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
1612 "%s: error getting name list (kvm_nlist): %s",
1613 __func__, kvm_geterr(kd));
1616 return(readkmem(kd, nl[0].n_value, buf, nbytes));
1620 * This duplicates the functionality of the kernel sysctl handler for poking
1621 * through crash dumps.
1624 get_devstat_kvm(kvm_t *kd)
1628 struct devstat *nds;
1630 struct devstatlist dhead;
1634 if ((num_devs = devstat_getnumdevs(kd)) <= 0)
1636 if (KREADNL(kd, X_DEVICE_STATQ, dhead) == -1)
1639 nds = STAILQ_FIRST(&dhead);
1641 if ((rv = malloc(sizeof(gen))) == NULL) {
1642 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
1643 "%s: out of memory (initial malloc failed)",
1647 gen = devstat_getgeneration(kd);
1648 memcpy(rv, &gen, sizeof(gen));
1651 * Now push out all the devices.
1653 for (i = 0; (nds != NULL) && (i < num_devs);
1654 nds = STAILQ_NEXT(nds, dev_links), i++) {
1655 if (readkmem(kd, (long)nds, &ds, sizeof(ds)) == -1) {
1660 rv = (char *)reallocf(rv, sizeof(gen) +
1661 sizeof(ds) * (i + 1));
1663 snprintf(devstat_errbuf, sizeof(devstat_errbuf),
1664 "%s: out of memory (malloc failed)",
1668 memcpy(rv + wp, &ds, sizeof(ds));