root/usr.bin/vmstat/vmstat.c
/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1980, 1986, 1991, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/proc.h>
#include <sys/uio.h>
#include <sys/namei.h>
#include <sys/malloc.h>
#include <sys/signal.h>
#include <sys/fcntl.h>
#include <sys/ioctl.h>
#include <sys/resource.h>
#include <sys/sysctl.h>
#include <sys/time.h>
#include <sys/user.h>
#define _WANT_VMMETER
#include <sys/vmmeter.h>
#include <sys/pcpu.h>

#include <vm/vm_param.h>

#include <ctype.h>
#include <devstat.h>
#include <errno.h>
#include <inttypes.h>
#include <kvm.h>
#include <limits.h>
#include <memstat.h>
#include <nlist.h>
#include <paths.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <time.h>
#include <unistd.h>
#include <libutil.h>
#include <libxo/xo.h>

#define VMSTAT_XO_VERSION "2"

static char da[] = "da";

enum x_stats { X_SUM, X_HZ, X_STATHZ, X_NCHSTATS, X_INTRNAMES, X_SINTRNAMES,
    X_INTRCNT, X_SINTRCNT, X_NINTRCNT };

static struct nlist namelist[] = {
        [X_SUM] = { .n_name = "_vm_cnt", },
        [X_HZ] = { .n_name = "_hz", },
        [X_STATHZ] = { .n_name = "_stathz", },
        [X_NCHSTATS] = { .n_name = "_nchstats", },
        [X_INTRNAMES] = { .n_name = "_intrnames", },
        [X_SINTRNAMES] = { .n_name = "_sintrnames", },
        [X_INTRCNT] = { .n_name = "_intrcnt", },
        [X_SINTRCNT] = { .n_name = "_sintrcnt", },
        [X_NINTRCNT] = { .n_name = "_nintrcnt", },
        { .n_name = NULL, },
};

static struct devstat_match *matches;
static struct device_selection *dev_select;
static struct statinfo cur, last;
static devstat_select_mode select_mode;
static size_t size_cp_times;
static long *cur_cp_times, *last_cp_times;
static long generation, select_generation;
static int hz, hdrcnt, maxshowdevs;
static int num_devices, num_devices_specified;
static int num_matches, num_selected, num_selections;
static char **specified_devices;

static struct __vmmeter {
        uint64_t v_swtch;
        uint64_t v_trap;
        uint64_t v_syscall;
        uint64_t v_intr;
        uint64_t v_soft;
        uint64_t v_vm_faults;
        uint64_t v_io_faults;
        uint64_t v_cow_faults;
        uint64_t v_cow_optim;
        uint64_t v_zfod;
        uint64_t v_ozfod;
        uint64_t v_swapin;
        uint64_t v_swapout;
        uint64_t v_swappgsin;
        uint64_t v_swappgsout;
        uint64_t v_vnodein;
        uint64_t v_vnodeout;
        uint64_t v_vnodepgsin;
        uint64_t v_vnodepgsout;
        uint64_t v_intrans;
        uint64_t v_reactivated;
        uint64_t v_pdwakeups;
        uint64_t v_pdpages;
        uint64_t v_pdshortfalls;
        uint64_t v_dfree;
        uint64_t v_pfree;
        uint64_t v_tfree;
        uint64_t v_forks;
        uint64_t v_vforks;
        uint64_t v_rforks;
        uint64_t v_kthreads;
        uint64_t v_forkpages;
        uint64_t v_vforkpages;
        uint64_t v_rforkpages;
        uint64_t v_kthreadpages;
        u_int v_page_size;
        u_int v_page_count;
        u_int v_free_reserved;
        u_int v_free_target;
        u_int v_free_min;
        u_int v_free_count;
        u_int v_wire_count;
        u_long v_user_wire_count;
        u_int v_nofree_count;
        u_int v_active_count;
        u_int v_inactive_target;
        u_int v_inactive_count;
        u_int v_laundry_count;
        u_int v_pageout_free_min;
        u_int v_interrupt_free_min;
        u_int v_free_severe;
} sum, osum;

#define VMSTAT_DEFAULT_LINES    20      /* Default number of `winlines'. */
static volatile sig_atomic_t wresized;          /* Tty resized when non-zero. */
static int winlines = VMSTAT_DEFAULT_LINES; /* Current number of tty rows. */

static int      aflag;
static int      nflag;
static int      Pflag;
static int      hflag;

static kvm_t    *kd;

#define FORKSTAT        0x01
#define INTRSTAT        0x02
#define MEMSTAT         0x04
#define SUMSTAT         0x08
#define TIMESTAT        0x10
#define VMSTAT          0x20
#define ZMEMSTAT        0x40
#define OBJSTAT         0x80

static void     cpustats(void);
static void     pcpustats(u_long, int);
static void     devstats(void);
static void     doforkst(void);
static void     dointr(unsigned int, int);
static void     doobjstat(void);
static void     dosum(void);
static void     dovmstat(unsigned int, int);
static void     domemstat_malloc(void);
static void     domemstat_zone(void);
static void     kread(int, void *, size_t);
static void     kreado(int, void *, size_t, size_t);
static void     kreadptr(uintptr_t, void *, size_t);
static void     needhdr(int);
static void     needresize(int);
static void     doresize(void);
static void     printhdr(int, u_long);
static void     usage(void);

static long     pct(long, long);
static long long        getuptime(void);

static char     **getdrivedata(char **);

int
main(int argc, char *argv[])
{
        char *bp, *buf, *memf, *nlistf;
        float f;
        int bufsize, c, reps, todo;
        size_t len;
        unsigned int interval;
        char errbuf[_POSIX2_LINE_MAX];

        memf = nlistf = NULL;
        interval = reps = todo = 0;
        maxshowdevs = 2;

        argc = xo_parse_args(argc, argv);
        if (argc < 0)
                return (argc);

        hflag = isatty(1);

        while ((c = getopt(argc, argv, "ac:fhHiM:mN:n:oPp:sw:z")) != -1) {
                switch (c) {
                case 'a':
                        aflag++;
                        break;
                case 'c':
                        reps = atoi(optarg);
                        break;
                case 'P':
                        Pflag++;
                        break;
                case 'f':
                        todo |= FORKSTAT;
                        break;
                case 'h':
                        hflag = 1;
                        break;
                case 'H':
                        hflag = 0;
                        break;
                case 'i':
                        todo |= INTRSTAT;
                        break;
                case 'M':
                        memf = optarg;
                        break;
                case 'm':
                        todo |= MEMSTAT;
                        break;
                case 'N':
                        nlistf = optarg;
                        break;
                case 'n':
                        nflag = 1;
                        maxshowdevs = atoi(optarg);
                        if (maxshowdevs < 0)
                                xo_errx(1, "number of devices %d is < 0",
                                    maxshowdevs);
                        break;
                case 'o':
                        todo |= OBJSTAT;
                        break;
                case 'p':
                        if (devstat_buildmatch(optarg, &matches, &num_matches)
                            != 0)
                                xo_errx(1, "%s", devstat_errbuf);
                        break;
                case 's':
                        todo |= SUMSTAT;
                        break;
                case 'w':
                        /* Convert to milliseconds. */
                        f = atof(optarg);
                        interval = f * 1000;
                        break;
                case 'z':
                        todo |= ZMEMSTAT;
                        break;
                case '?':
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;

        xo_set_version(VMSTAT_XO_VERSION);
        xo_open_container("vmstat");
        if (!hflag)
                xo_set_options(NULL, "no-humanize");
        if (todo == 0)
                todo = VMSTAT;

        if (memf != NULL) {
                kd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, errbuf);
                if (kd == NULL)
                        xo_errx(1, "kvm_openfiles: %s", errbuf);
        }

retry_nlist:
        if (kd != NULL && (c = kvm_nlist(kd, namelist)) != 0) {
                if (c > 0) {
                        bufsize = 0;
                        len = 0;

                        /*
                         * 'cnt' was renamed to 'vm_cnt'.  If 'vm_cnt' is not
                         * found try looking up older 'cnt' symbol.
                         * */
                        if (namelist[X_SUM].n_type == 0 &&
                            strcmp(namelist[X_SUM].n_name, "_vm_cnt") == 0) {
                                namelist[X_SUM].n_name = "_cnt";
                                goto retry_nlist;
                        }

                        /*
                         * 'nintrcnt' doesn't exist in older kernels, but
                         * that isn't fatal.
                         */
                        if (namelist[X_NINTRCNT].n_type == 0 && c == 1)
                                goto nlist_ok;

                        for (c = 0; c < (int)(nitems(namelist)); c++)
                                if (namelist[c].n_type == 0)
                                        bufsize += strlen(namelist[c].n_name)
                                            + 1;
                        bufsize += len + 1;
                        buf = bp = alloca(bufsize);

                        for (c = 0; c < (int)(nitems(namelist)); c++)
                                if (namelist[c].n_type == 0) {
                                        xo_error(" %s",
                                            namelist[c].n_name);
                                        len = strlen(namelist[c].n_name);
                                        *bp++ = ' ';
                                        memcpy(bp, namelist[c].n_name, len);
                                        bp += len;
                                }
                        *bp = '\0';
                        xo_error("undefined symbols:\n", buf);
                } else
                        xo_warnx("kvm_nlist: %s", kvm_geterr(kd));
                if (xo_finish() < 0)
                        xo_err(EXIT_FAILURE, "stdout");
                exit(EXIT_FAILURE);
        }
nlist_ok:
        if (kd && Pflag)
                xo_errx(1, "Cannot use -P with crash dumps");

        if (todo & VMSTAT) {
                /*
                 * Make sure that the userland devstat version matches the
                 * kernel devstat version.  If not, exit and print a
                 * message informing the user of his mistake.
                 */
                if (devstat_checkversion(NULL) < 0)
                        xo_errx(1, "%s", devstat_errbuf);


                argv = getdrivedata(argv);
        }

        if (*argv) {
                f = atof(*argv);
                interval = f * 1000;
                if (*++argv)
                        reps = atoi(*argv);
        }

        if (interval) {
                if (!reps)
                        reps = -1;
        } else if (reps)
                interval = 1 * 1000;

        if (todo & FORKSTAT)
                doforkst();
        if (todo & MEMSTAT)
                domemstat_malloc();
        if (todo & ZMEMSTAT)
                domemstat_zone();
        if (todo & SUMSTAT)
                dosum();
        if (todo & OBJSTAT)
                doobjstat();
        if (todo & INTRSTAT)
                dointr(interval, reps);
        if (todo & VMSTAT)
                dovmstat(interval, reps);
        xo_close_container("vmstat");
        if (xo_finish() < 0)
                xo_err(EXIT_FAILURE, "stdout");
        exit(EXIT_SUCCESS);
}

static int
mysysctl(const char *name, void *oldp, size_t *oldlenp)
{
        int error;

        error = sysctlbyname(name, oldp, oldlenp, NULL, 0);
        if (error != 0 && errno != ENOMEM)
                xo_err(1, "sysctl(%s)", name);
        return (error);
}

static char **
getdrivedata(char **argv)
{

        if ((num_devices = devstat_getnumdevs(NULL)) < 0)
                xo_errx(1, "%s", devstat_errbuf);

        cur.dinfo = (struct devinfo *)calloc(1, sizeof(struct devinfo));
        last.dinfo = (struct devinfo *)calloc(1, sizeof(struct devinfo));

        if (devstat_getdevs(NULL, &cur) == -1)
                xo_errx(1, "%s", devstat_errbuf);

        num_devices = cur.dinfo->numdevs;
        generation = cur.dinfo->generation;

        specified_devices = malloc(sizeof(char *));
        for (num_devices_specified = 0; *argv; ++argv) {
                if (isdigit(**argv))
                        break;
                num_devices_specified++;
                specified_devices = reallocf(specified_devices,
                    sizeof(char *) * num_devices_specified);
                if (specified_devices == NULL) {
                        xo_errx(1, "%s", "reallocf (specified_devices)");
                }
                specified_devices[num_devices_specified - 1] = *argv;
        }
        dev_select = NULL;

        if (nflag == 0 && maxshowdevs < num_devices_specified)
                maxshowdevs = num_devices_specified;

        /*
         * People are generally only interested in disk statistics when
         * they're running vmstat.  So, that's what we're going to give
         * them if they don't specify anything by default.  We'll also give
         * them any other random devices in the system so that we get to
         * maxshowdevs devices, if that many devices exist.  If the user
         * specifies devices on the command line, either through a pattern
         * match or by naming them explicitly, we will give the user only
         * those devices.
         */
        if ((num_devices_specified == 0) && (num_matches == 0)) {
                if (devstat_buildmatch(da, &matches, &num_matches) != 0)
                        xo_errx(1, "%s", devstat_errbuf);
                select_mode = DS_SELECT_ADD;
        } else
                select_mode = DS_SELECT_ONLY;

        /*
         * At this point, selectdevs will almost surely indicate that the
         * device list has changed, so we don't look for return values of 0
         * or 1.  If we get back -1, though, there is an error.
         */
        if (devstat_selectdevs(&dev_select, &num_selected, &num_selections,
            &select_generation, generation, cur.dinfo->devices,
            num_devices, matches, num_matches, specified_devices,
            num_devices_specified, select_mode,
            maxshowdevs, 0) == -1)
                xo_errx(1, "%s", devstat_errbuf);

        return(argv);
}

/* Return system uptime in nanoseconds */
static long long
getuptime(void)
{
        struct timespec sp;

        (void)clock_gettime(CLOCK_UPTIME, &sp);
        return((long long)sp.tv_sec * 1000000000LL + sp.tv_nsec);
}

static void
fill_vmmeter(struct __vmmeter *vmmp)
{
        struct vmmeter vm_cnt;
        size_t size;

        if (kd != NULL) {
                kread(X_SUM, &vm_cnt, sizeof(vm_cnt));
#define GET_COUNTER(name) \
                vmmp->name = kvm_counter_u64_fetch(kd, (u_long)vm_cnt.name)
                GET_COUNTER(v_swtch);
                GET_COUNTER(v_trap);
                GET_COUNTER(v_syscall);
                GET_COUNTER(v_intr);
                GET_COUNTER(v_soft);
                GET_COUNTER(v_vm_faults);
                GET_COUNTER(v_io_faults);
                GET_COUNTER(v_cow_faults);
                GET_COUNTER(v_cow_optim);
                GET_COUNTER(v_zfod);
                GET_COUNTER(v_ozfod);
                GET_COUNTER(v_swapin);
                GET_COUNTER(v_swapout);
                GET_COUNTER(v_swappgsin);
                GET_COUNTER(v_swappgsout);
                GET_COUNTER(v_vnodein);
                GET_COUNTER(v_vnodeout);
                GET_COUNTER(v_vnodepgsin);
                GET_COUNTER(v_vnodepgsout);
                GET_COUNTER(v_intrans);
                GET_COUNTER(v_tfree);
                GET_COUNTER(v_forks);
                GET_COUNTER(v_vforks);
                GET_COUNTER(v_rforks);
                GET_COUNTER(v_kthreads);
                GET_COUNTER(v_forkpages);
                GET_COUNTER(v_vforkpages);
                GET_COUNTER(v_rforkpages);
                GET_COUNTER(v_kthreadpages);
#undef GET_COUNTER
        } else {
#define GET_VM_STATS(cat, name) do {                                    \
        size = sizeof(vmmp->name);                                      \
        mysysctl("vm.stats." #cat "." #name, &vmmp->name, &size);       \
} while (0)
                /* sys */
                GET_VM_STATS(sys, v_swtch);
                GET_VM_STATS(sys, v_trap);
                GET_VM_STATS(sys, v_syscall);
                GET_VM_STATS(sys, v_intr);
                GET_VM_STATS(sys, v_soft);

                /* vm */
                GET_VM_STATS(vm, v_vm_faults);
                GET_VM_STATS(vm, v_io_faults);
                GET_VM_STATS(vm, v_cow_faults);
                GET_VM_STATS(vm, v_cow_optim);
                GET_VM_STATS(vm, v_zfod);
                GET_VM_STATS(vm, v_ozfod);
                GET_VM_STATS(vm, v_swapin);
                GET_VM_STATS(vm, v_swapout);
                GET_VM_STATS(vm, v_swappgsin);
                GET_VM_STATS(vm, v_swappgsout);
                GET_VM_STATS(vm, v_vnodein);
                GET_VM_STATS(vm, v_vnodeout);
                GET_VM_STATS(vm, v_vnodepgsin);
                GET_VM_STATS(vm, v_vnodepgsout);
                GET_VM_STATS(vm, v_intrans);
                GET_VM_STATS(vm, v_reactivated);
                GET_VM_STATS(vm, v_pdwakeups);
                GET_VM_STATS(vm, v_pdpages);
                GET_VM_STATS(vm, v_pdshortfalls);
                GET_VM_STATS(vm, v_dfree);
                GET_VM_STATS(vm, v_pfree);
                GET_VM_STATS(vm, v_tfree);
                GET_VM_STATS(vm, v_page_size);
                GET_VM_STATS(vm, v_page_count);
                GET_VM_STATS(vm, v_free_reserved);
                GET_VM_STATS(vm, v_free_target);
                GET_VM_STATS(vm, v_free_min);
                GET_VM_STATS(vm, v_free_count);
                GET_VM_STATS(vm, v_wire_count);
                GET_VM_STATS(vm, v_user_wire_count);
                GET_VM_STATS(vm, v_nofree_count);
                GET_VM_STATS(vm, v_active_count);
                GET_VM_STATS(vm, v_inactive_target);
                GET_VM_STATS(vm, v_inactive_count);
                GET_VM_STATS(vm, v_laundry_count);
                GET_VM_STATS(vm, v_pageout_free_min);
                GET_VM_STATS(vm, v_interrupt_free_min);
                /*GET_VM_STATS(vm, v_free_severe);*/
                GET_VM_STATS(vm, v_forks);
                GET_VM_STATS(vm, v_vforks);
                GET_VM_STATS(vm, v_rforks);
                GET_VM_STATS(vm, v_kthreads);
                GET_VM_STATS(vm, v_forkpages);
                GET_VM_STATS(vm, v_vforkpages);
                GET_VM_STATS(vm, v_rforkpages);
                GET_VM_STATS(vm, v_kthreadpages);
#undef GET_VM_STATS
        }
}

static void
fill_vmtotal(struct vmtotal *vmtp)
{
        size_t size;

        if (kd != NULL) {
                /* XXX fill vmtp */
                xo_errx(1, "not implemented");
        } else {
                size = sizeof(*vmtp);
                mysysctl("vm.vmtotal", vmtp, &size);
                if (size != sizeof(*vmtp))
                        xo_errx(1, "vm.total size mismatch");
        }
}

/* Determine how many cpu columns, and what index they are in kern.cp_times */
static void
getcpuinfo(u_long *maskp, int *maxidp)
{
        long *times;
        u_long mask;
        size_t size;
        int empty, i, j, maxcpu, maxid;

        if (kd != NULL)
                xo_errx(1, "not implemented");
        mask = 0;
        size = sizeof(maxcpu);
        mysysctl("kern.smp.maxcpus", &maxcpu, &size);
        if (size != sizeof(maxcpu))
                xo_errx(1, "sysctl kern.smp.maxcpus");
        size = sizeof(long) * maxcpu * CPUSTATES;
        times = malloc(size);
        if (times == NULL)
                xo_err(1, "malloc %zd bytes", size);
        mysysctl("kern.cp_times", times, &size);
        maxid = (size / CPUSTATES / sizeof(long)) - 1;
        for (i = 0; i <= maxid; i++) {
                empty = 1;
                for (j = 0; empty && j < CPUSTATES; j++) {
                        if (times[i * CPUSTATES + j] != 0)
                                empty = 0;
                }
                if (!empty)
                        mask |= (1ul << i);
        }
        if (maskp)
                *maskp = mask;
        if (maxidp)
                *maxidp = maxid;
}

static void
dovmstat(unsigned int interval, int reps)
{
        struct clockinfo clockrate;
        struct vmtotal total;
        struct devinfo *tmp_dinfo;
        u_long cpumask;
        size_t size;
        time_t uptime, halfuptime;
        int maxid, rate_adj, retval;

        uptime = getuptime() / 1000000000LL;
        halfuptime = uptime / 2;
        rate_adj = 1;
        maxid = 0;
        cpumask = 0;

        /*
         * If the user stops the program (control-Z) and then resumes it,
         * print out the header again.
         */
        (void)signal(SIGCONT, needhdr);

        /*
         * If our standard output is a tty, then install a SIGWINCH handler
         * and set wresized so that our first iteration through the main
         * vmstat loop will peek at the terminal's current rows to find out
         * how many lines can fit in a screenful of output.
         */
        if (isatty(fileno(stdout)) != 0) {
                wresized = 1;
                (void)signal(SIGWINCH, needresize);
        } else {
                wresized = 0;
                winlines = VMSTAT_DEFAULT_LINES;
        }

        if (kd != NULL) {
                if (namelist[X_STATHZ].n_type != 0 &&
                    namelist[X_STATHZ].n_value != 0)
                        kread(X_STATHZ, &hz, sizeof(hz));
                if (!hz)
                        kread(X_HZ, &hz, sizeof(hz));
        } else {
                size = sizeof(clockrate);
                mysysctl("kern.clockrate", &clockrate, &size);
                if (size != sizeof(clockrate))
                        xo_errx(1, "clockrate size mismatch");
                hz = clockrate.hz;
        }

        if (Pflag) {
                getcpuinfo(&cpumask, &maxid);
                size_cp_times = sizeof(long) * (maxid + 1) * CPUSTATES;
                cur_cp_times = calloc(1, size_cp_times);
                last_cp_times = calloc(1, size_cp_times);
        }
        for (hdrcnt = 1;;) {
                if (!--hdrcnt)
                        printhdr(maxid, cpumask);
                if (kd != NULL) {
                        if (kvm_getcptime(kd, cur.cp_time) < 0)
                                xo_errx(1, "kvm_getcptime: %s", kvm_geterr(kd));
                } else {
                        size = sizeof(cur.cp_time);
                        mysysctl("kern.cp_time", &cur.cp_time, &size);
                        if (size != sizeof(cur.cp_time))
                                xo_errx(1, "cp_time size mismatch");
                }
                if (Pflag) {
                        size = size_cp_times;
                        mysysctl("kern.cp_times", cur_cp_times, &size);
                        if (size != size_cp_times)
                                xo_errx(1, "cp_times mismatch");
                }

                tmp_dinfo = last.dinfo;
                last.dinfo = cur.dinfo;
                cur.dinfo = tmp_dinfo;
                last.snap_time = cur.snap_time;

                /*
                 * Here what we want to do is refresh our device stats.
                 * getdevs() returns 1 when the device list has changed.
                 * If the device list has changed, we want to go through
                 * the selection process again, in case a device that we
                 * were previously displaying has gone away.
                 */
                switch (devstat_getdevs(NULL, &cur)) {
                case -1:
                        xo_errx(1, "%s", devstat_errbuf);
                        break;
                case 1:
                        num_devices = cur.dinfo->numdevs;
                        generation = cur.dinfo->generation;

                        retval = devstat_selectdevs(&dev_select, &num_selected,
                            &num_selections, &select_generation,
                            generation, cur.dinfo->devices,
                            num_devices, matches, num_matches,
                            specified_devices,
                            num_devices_specified, select_mode,
                            maxshowdevs, 0);
                        switch (retval) {
                        case -1:
                                xo_errx(1, "%s", devstat_errbuf);
                                break;
                        case 1:
                                printhdr(maxid, cpumask);
                                break;
                        default:
                                break;
                        }
                        break;
                default:
                        break;
                }

                fill_vmmeter(&sum);
                fill_vmtotal(&total);
                xo_open_container("processes");
                xo_emit("{:runnable/%2d} {:waiting/%2ld} "
                    "{:swapped-out/%2ld}", total.t_rq - 1, total.t_dw +
                    total.t_pw, total.t_sw);
                xo_close_container("processes");
                xo_open_container("memory");
#define rate(x) (unsigned long)(((x) * rate_adj + halfuptime) / uptime)
                xo_emit(" {[:4}{h,hn-decimal:available-memory/%ju}{]:}",
                    (uintmax_t)total.t_avm * sum.v_page_size);
                xo_emit(" {[:4}{h,hn-decimal:free-memory/%ju}{]:}",
                    (uintmax_t)total.t_free * sum.v_page_size);
                xo_emit(" {[:4}{h,hn-decimal,hn-1000:total-page-faults/%lu}{]:} ",
                    rate(sum.v_vm_faults - osum.v_vm_faults));
                xo_close_container("memory");

                xo_open_container("paging-rates");
                xo_emit("{:page-reactivated/%3lu} ",
                    rate(sum.v_reactivated - osum.v_reactivated));
                xo_emit("{:paged-in/%3lu} ",
                    rate(sum.v_swapin + sum.v_vnodein -
                    (osum.v_swapin + osum.v_vnodein)));
                xo_emit("{:paged-out/%3lu}",
                    rate(sum.v_swapout + sum.v_vnodeout -
                    (osum.v_swapout + osum.v_vnodeout)));
                xo_emit(" {[:4}{h,hn-decimal,hn-1000:freed/%lu}{]:}",
                    rate(sum.v_tfree - osum.v_tfree));
                xo_emit(" {[:4}{h,hn-decimal,hn-1000:scanned/%lu}{]:}",
                    rate(sum.v_pdpages - osum.v_pdpages));
                xo_close_container("paging-rates");

                devstats();
                xo_open_container("fault-rates");
                xo_emit(" {[:4}{h,hn-decimal,hn-1000:interrupts/%lu}{]:}"
                    " {[:4}{h,hn-decimal,hn-1000:system-calls/%lu}{]:}"
                    " {[:4}{h,hn-decimal,hn-1000:context-switches/%lu}{]:}",
                    rate(sum.v_intr - osum.v_intr),
                    rate(sum.v_syscall - osum.v_syscall),
                    rate(sum.v_swtch - osum.v_swtch));
                xo_close_container("fault-rates");
                if (Pflag)
                        pcpustats(cpumask, maxid);
                else
                        cpustats();
                xo_emit("\n");
                if (xo_flush() < 0)
                        xo_err(EXIT_FAILURE, "stdout");
                if (reps >= 0 && --reps <= 0)
                        break;
                osum = sum;
                uptime = interval;
                rate_adj = 1000;
                /*
                 * We round upward to avoid losing low-frequency events
                 * (i.e., >= 1 per interval but < 1 per millisecond).
                 */
                if (interval != 1)
                        halfuptime = (uptime + 1) / 2;
                else
                        halfuptime = 0;
                (void)usleep(interval * 1000);
        }
}

static void
printhdr(int maxid, u_long cpumask)
{
        int i, num_shown;

        num_shown = MIN(num_selected, maxshowdevs);
        xo_emit(" {T:procs}    {T:memory}    {T:/page%*s}", 19, "");
        if (num_shown > 1)
                xo_emit("   {T:/disks %*s}  ", num_shown * 5 - 7, "");
        else if (num_shown == 1)
                xo_emit("   {T:disks} ");
        xo_emit(" {T:faults}      ");
        if (Pflag) {
                for (i = 0; i <= maxid; i++) {
                        if (cpumask & (1ul << i))
                                xo_emit("  {T:/cpu%d}   ", i);
                }
                xo_emit("\n");
        } else
                xo_emit(" {T:cpu}\n");
        xo_emit(" {T:r}  {T:b}  {T:w}  {T:avm}  {T:fre}  {T:flt}  {T:re}"
            "  {T:pi}  {T:po}   {T:fr}   {T:sr} ");
        for (i = 0; i < num_devices; i++)
                if ((dev_select[i].selected) &&
                    (dev_select[i].selected <= maxshowdevs))
                        xo_emit("{T:/%3.3s%d} ", dev_select[i].device_name,
                            dev_select[i].unit_number);
        xo_emit("  {T:in}   {T:sy}   {T:cs}");
        if (Pflag) {
                for (i = 0; i <= maxid; i++) {
                        if (cpumask & (1ul << i))
                                xo_emit(" {T:us} {T:sy} {T:id}");
                }
                xo_emit("\n");
        } else
                xo_emit(" {T:us} {T:sy} {T:id}\n");
        if (wresized != 0)
                doresize();
        hdrcnt = winlines;
}

/*
 * Force a header to be prepended to the next output.
 */
static void
needhdr(int dummy __unused)
{

        hdrcnt = 1;
}

/*
 * When the terminal is resized, force an update of the maximum number of rows
 * printed between each header repetition.  Then force a new header to be
 * prepended to the next output.
 */
void
needresize(int signo __unused)
{

        wresized = 1;
        hdrcnt = 1;
}

/*
 * Update the global `winlines' count of terminal rows.
 */
void
doresize(void)
{
        struct winsize w;
        int status;

        for (;;) {
                status = ioctl(fileno(stdout), TIOCGWINSZ, &w);
                if (status == -1 && errno == EINTR)
                        continue;
                else if (status == -1)
                        xo_err(1, "ioctl");
                if (w.ws_row > 3)
                        winlines = w.ws_row - 3;
                else
                        winlines = VMSTAT_DEFAULT_LINES;
                break;
        }

        /*
         * Inhibit doresize() calls until we are rescheduled by SIGWINCH.
         */
        wresized = 0;
}

static long
pct(long top, long bot)
{
        long ans;

        if (bot == 0)
                return(0);
        ans = (quad_t)top * 100 / bot;
        return (ans);
}

#define PCT(top, bot) pct((long)(top), (long)(bot))

static void
dosum(void)
{
        struct nchstats lnchstats;
        size_t size;
        long nchtotal;

        fill_vmmeter(&sum);
        xo_open_container("summary-statistics");
        xo_emit("{:context-switches/%9u} {N:cpu context switches}\n",
            sum.v_swtch);
        xo_emit("{:interrupts/%9u} {N:device interrupts}\n",
            sum.v_intr);
        xo_emit("{:software-interrupts/%9u} {N:software interrupts}\n",
            sum.v_soft);
        xo_emit("{:traps/%9u} {N:traps}\n", sum.v_trap);
        xo_emit("{:system-calls/%9u} {N:system calls}\n",
            sum.v_syscall);
        xo_emit("{:kernel-threads/%9u} {N:kernel threads created}\n",
            sum.v_kthreads);
        xo_emit("{:forks/%9u} {N: fork() calls}\n", sum.v_forks);
        xo_emit("{:vforks/%9u} {N:vfork() calls}\n",
            sum.v_vforks);
        xo_emit("{:rforks/%9u} {N:rfork() calls}\n",
            sum.v_rforks);
        xo_emit("{:swap-ins/%9u} {N:swap pager pageins}\n",
            sum.v_swapin);
        xo_emit("{:swap-in-pages/%9u} {N:swap pager pages paged in}\n",
            sum.v_swappgsin);
        xo_emit("{:swap-outs/%9u} {N:swap pager pageouts}\n",
            sum.v_swapout);
        xo_emit("{:swap-out-pages/%9u} {N:swap pager pages paged out}\n",
            sum.v_swappgsout);
        xo_emit("{:vnode-page-ins/%9u} {N:vnode pager pageins}\n",
            sum.v_vnodein);
        xo_emit("{:vnode-page-in-pages/%9u} {N:vnode pager pages paged in}\n",
            sum.v_vnodepgsin);
        xo_emit("{:vnode-page-outs/%9u} {N:vnode pager pageouts}\n",
            sum.v_vnodeout);
        xo_emit("{:vnode-page-out-pages/%9u} {N:vnode pager pages paged out}\n",
            sum.v_vnodepgsout);
        xo_emit("{:page-daemon-wakeups/%9u} {N:page daemon wakeups}\n",
            sum.v_pdwakeups);
        xo_emit("{:page-daemon-pages/%9u} {N:pages examined by the page "
            "daemon}\n", sum.v_pdpages);
        xo_emit("{:page-reclamation-shortfalls/%9u} {N:clean page reclamation "
            "shortfalls}\n", sum.v_pdshortfalls);
        xo_emit("{:reactivated/%9u} {N:pages reactivated by the page daemon}\n",
            sum.v_reactivated);
        xo_emit("{:copy-on-write-faults/%9u} {N:copy-on-write faults}\n",
            sum.v_cow_faults);
        xo_emit("{:copy-on-write-optimized-faults/%9u} {N:copy-on-write "
            "optimized faults}\n", sum.v_cow_optim);
        xo_emit("{:zero-fill-pages/%9u} {N:zero fill pages zeroed}\n",
            sum.v_zfod);
        xo_emit("{:zero-fill-prezeroed/%9u} {N:zero fill pages prezeroed}\n",
            sum.v_ozfod);
        xo_emit("{:intransit-blocking/%9u} {N:intransit blocking page faults}\n",
            sum.v_intrans);
        xo_emit("{:total-faults/%9u} {N:total VM faults taken}\n",
            sum.v_vm_faults);
        xo_emit("{:faults-requiring-io/%9u} {N:page faults requiring I\\/O}\n",
            sum.v_io_faults);
        xo_emit("{:faults-from-thread-creation/%9u} {N:pages affected by "
            "kernel thread creation}\n", sum.v_kthreadpages);
        xo_emit("{:faults-from-fork/%9u} {N:pages affected by  fork}()\n",
            sum.v_forkpages);
        xo_emit("{:faults-from-vfork/%9u} {N:pages affected by vfork}()\n",
            sum.v_vforkpages);
        xo_emit("{:pages-rfork/%9u} {N:pages affected by rfork}()\n",
            sum.v_rforkpages);
        xo_emit("{:pages-freed/%9u} {N:pages freed}\n",
            sum.v_tfree);
        xo_emit("{:pages-freed-by-daemon/%9u} {N:pages freed by daemon}\n",
            sum.v_dfree);
        xo_emit("{:pages-freed-on-exit/%9u} {N:pages freed by exiting processes}\n",
            sum.v_pfree);
        xo_emit("{:active-pages/%9u} {N:pages active}\n",
            sum.v_active_count);
        xo_emit("{:inactive-pages/%9u} {N:pages inactive}\n",
            sum.v_inactive_count);
        xo_emit("{:laundry-pages/%9u} {N:pages in the laundry queue}\n",
            sum.v_laundry_count);
        xo_emit("{:wired-pages/%9u} {N:pages wired down}\n",
            sum.v_wire_count);
        xo_emit("{:virtual-user-wired-pages/%9lu} {N:virtual user pages wired "
            "down}\n", sum.v_user_wire_count);
        xo_emit("{:nofree-pages/%9u} {N:permanently allocated pages}\n",
            sum.v_nofree_count);
        xo_emit("{:free-pages/%9u} {N:pages free}\n",
            sum.v_free_count);
        xo_emit("{:bytes-per-page/%9u} {N:bytes per page}\n", sum.v_page_size);
        if (kd != NULL) {
                kread(X_NCHSTATS, &lnchstats, sizeof(lnchstats));
        } else {
                size = sizeof(lnchstats);
                mysysctl("vfs.cache.nchstats", &lnchstats, &size);
                if (size != sizeof(lnchstats))
                        xo_errx(1, "vfs.cache.nchstats size mismatch");
        }
        nchtotal = lnchstats.ncs_goodhits + lnchstats.ncs_neghits +
            lnchstats.ncs_badhits + lnchstats.ncs_falsehits +
            lnchstats.ncs_miss + lnchstats.ncs_long;
        xo_emit("{:total-name-lookups/%9ld} {N:total name lookups}\n",
            nchtotal);
        xo_emit("{P:/%9s} {N:cache hits} "
            "({:positive-cache-hits/%ld}% pos + "
            "{:negative-cache-hits/%ld}% {N:neg}) "
            "system {:cache-hit-percent/%ld}% per-directory\n",
            "", PCT(lnchstats.ncs_goodhits, nchtotal),
            PCT(lnchstats.ncs_neghits, nchtotal),
            PCT(lnchstats.ncs_pass2, nchtotal));
        xo_emit("{P:/%9s} {L:deletions} {:deletions/%ld}%, "
            "{L:falsehits} {:false-hits/%ld}%, "
            "{L:toolong} {:too-long/%ld}%\n", "",
            PCT(lnchstats.ncs_badhits, nchtotal),
            PCT(lnchstats.ncs_falsehits, nchtotal),
            PCT(lnchstats.ncs_long, nchtotal));
        xo_close_container("summary-statistics");
}

static void
doforkst(void)
{

        fill_vmmeter(&sum);
        xo_open_container("fork-statistics");
        xo_emit("{:fork/%u} {N:forks}, {:fork-pages/%u} {N:pages}, "
            "{L:average} {:fork-average/%.2f}\n",
            sum.v_forks, sum.v_forkpages,
            sum.v_forks == 0 ? 0.0 :
            (double)sum.v_forkpages / sum.v_forks);
        xo_emit("{:vfork/%u} {N:vforks}, {:vfork-pages/%u} {N:pages}, "
            "{L:average} {:vfork-average/%.2f}\n",
            sum.v_vforks, sum.v_vforkpages,
            sum.v_vforks == 0 ? 0.0 :
            (double)sum.v_vforkpages / sum.v_vforks);
        xo_emit("{:rfork/%u} {N:rforks}, {:rfork-pages/%u} {N:pages}, "
            "{L:average} {:rfork-average/%.2f}\n",
            sum.v_rforks, sum.v_rforkpages,
            sum.v_rforks == 0 ? 0.0 :
            (double)sum.v_rforkpages / sum.v_rforks);
        xo_close_container("fork-statistics");
}

static void
devstats(void)
{
        long double busy_seconds, transfers_per_second;
        long tmp;
        int di, dn, state;

        for (state = 0; state < CPUSTATES; ++state) {
                tmp = cur.cp_time[state];
                cur.cp_time[state] -= last.cp_time[state];
                last.cp_time[state] = tmp;
        }

        busy_seconds = cur.snap_time - last.snap_time;

        xo_open_list("device");
        for (dn = 0; dn < num_devices; dn++) {
                if (dev_select[dn].selected == 0 ||
                    dev_select[dn].selected > maxshowdevs)
                        continue;

                di = dev_select[dn].position;

                if (devstat_compute_statistics(&cur.dinfo->devices[di],
                    &last.dinfo->devices[di], busy_seconds,
                    DSM_TRANSFERS_PER_SECOND, &transfers_per_second,
                    DSM_NONE) != 0)
                        xo_errx(1, "%s", devstat_errbuf);

                xo_open_instance("device");
                xo_emit("{ekq:name/%s%d}",
                    dev_select[dn].device_name,
                    dev_select[dn].unit_number);
                xo_emit("{[:5}{h,hn-decimal,hn-1000:transfers/%ju}{]:}",
                    (uintmax_t)transfers_per_second);
                xo_close_instance("device");
        }
        xo_close_list("device");
}

static void
percent(const char *name, long pctv, int *over)
{
        char fmt[64];

        snprintf(fmt, sizeof(fmt), " {:%s/%%%uld/%%ld}", name,
            (*over && pctv <= 9) ? 1 : 2);
        xo_emit(fmt, pctv);
        if (*over && pctv <= 9)
                (*over)--;
        else if (pctv >= 100)
                (*over)++;
}

static void
cpustats(void)
{
        long total;
        int state, over;

        total = 0;
        for (state = 0; state < CPUSTATES; ++state)
                total += cur.cp_time[state];
        if (total == 0)
                total = 1;
        over = 0;
        xo_open_container("cpu-statistics");
        percent("user", 100LL * (cur.cp_time[CP_USER] + cur.cp_time[CP_NICE]) /
            total, &over);
        percent("system", 100LL * (cur.cp_time[CP_SYS] + cur.cp_time[CP_INTR]) /
            total, &over);
        percent("idle", 100LL * cur.cp_time[CP_IDLE] / total, &over);
        xo_close_container("cpu-statistics");
}

static void
pcpustats(u_long cpumask, int maxid)
{
        long tmp, total;
        int i, state, over;

        /* devstats does this for cp_time */
        for (i = 0; i <= maxid; i++) {
                if ((cpumask & (1ul << i)) == 0)
                        continue;
                for (state = 0; state < CPUSTATES; ++state) {
                        tmp = cur_cp_times[i * CPUSTATES + state];
                        cur_cp_times[i * CPUSTATES + state] -= last_cp_times[i *
                            CPUSTATES + state];
                        last_cp_times[i * CPUSTATES + state] = tmp;
                }
        }

        over = 0;
        xo_open_list("cpu");
        for (i = 0; i <= maxid; i++) {
                if ((cpumask & (1ul << i)) == 0)
                        continue;
                xo_open_instance("cpu");
                xo_emit("{ke:name/%d}", i);
                total = 0;
                for (state = 0; state < CPUSTATES; ++state)
                        total += cur_cp_times[i * CPUSTATES + state];
                if (total == 0)
                        total = 1;
                percent("user",
                    100LL * (cur_cp_times[i * CPUSTATES + CP_USER] +
                    cur_cp_times[i * CPUSTATES + CP_NICE]) / total, &over);
                percent("system",
                    100LL * (cur_cp_times[i * CPUSTATES + CP_SYS] +
                    cur_cp_times[i * CPUSTATES + CP_INTR]) / total, &over);
                percent("idle",
                    100LL * cur_cp_times[i * CPUSTATES + CP_IDLE] / total,
                    &over);
                xo_close_instance("cpu");
        }
        xo_close_list("cpu");
}

static unsigned int
read_intrcnts(unsigned long **intrcnts)
{
        size_t intrcntlen;
        uintptr_t kaddr;

        if (kd != NULL) {
                kread(X_SINTRCNT, &intrcntlen, sizeof(intrcntlen));
                if ((*intrcnts = malloc(intrcntlen)) == NULL)
                        xo_err(1, "malloc()");
                if (namelist[X_NINTRCNT].n_type == 0)
                        kread(X_INTRCNT, *intrcnts, intrcntlen);
                else {
                        kread(X_INTRCNT, &kaddr, sizeof(kaddr));
                        kreadptr(kaddr, *intrcnts, intrcntlen);
                }
        } else {
                for (*intrcnts = NULL, intrcntlen = 1024; ; intrcntlen *= 2) {
                        *intrcnts = reallocf(*intrcnts, intrcntlen);
                        if (*intrcnts == NULL)
                                xo_err(1, "reallocf()");
                        if (mysysctl("hw.intrcnt", *intrcnts, &intrcntlen) == 0)
                                break;
                }
        }

        return (intrcntlen / sizeof(unsigned long));
}

static void
print_intrcnts(unsigned long *intrcnts, unsigned long *old_intrcnts,
    char *intrnames, unsigned int nintr, size_t istrnamlen, long long period_ms)
{
        uint64_t inttotal, old_inttotal, total_count, total_rate;
        unsigned long count, rate;
        unsigned int i;

        inttotal = 0;
        old_inttotal = 0;
        xo_open_list("interrupt");
        for (i = 0; i < nintr; i++) {
                if (intrnames[0] != '\0' && (*intrcnts != 0 || aflag)) {
                        count = *intrcnts - *old_intrcnts;
                        rate = ((uint64_t)count * 1000 + period_ms / 2) / period_ms;
                        xo_open_instance("interrupt");
                        xo_emit("{d:name/%-*s}{ket:name/%s} "
                            "{:total/%20lu} {:rate/%10lu}\n",
                            (int)istrnamlen, intrnames, intrnames, count, rate);
                        xo_close_instance("interrupt");
                }
                intrnames += strlen(intrnames) + 1;
                inttotal += *intrcnts++;
                old_inttotal += *old_intrcnts++;
        }
        total_count = inttotal - old_inttotal;
        total_rate = (total_count * 1000 + period_ms / 2) / period_ms;
        xo_close_list("interrupt");
        xo_emit("{L:/%-*s} {:total-interrupts/%20ju} "
            "{:total-rate/%10ju}\n", (int)istrnamlen,
            "Total", (uintmax_t)total_count, (uintmax_t)total_rate);
}

static void
dointr(unsigned int interval, int reps)
{
        unsigned long *intrcnts, *old_intrcnts;
        char *intrname, *intrnames;
        long long period_ms, old_uptime, uptime;
        size_t clen, inamlen, istrnamlen;
        uintptr_t kaddr;
        unsigned int nintr;

        old_intrcnts = NULL;
        uptime = getuptime();

        /* Get the names of each interrupt source */
        if (kd != NULL) {
                kread(X_SINTRNAMES, &inamlen, sizeof(inamlen));
                if ((intrnames = malloc(inamlen)) == NULL)
                        xo_err(1, "malloc()");
                if (namelist[X_NINTRCNT].n_type == 0)
                        kread(X_INTRNAMES, intrnames, inamlen);
                else {
                        kread(X_INTRNAMES, &kaddr, sizeof(kaddr));
                        kreadptr(kaddr, intrnames, inamlen);
                }
        } else {
                for (intrnames = NULL, inamlen = 1024; ; inamlen *= 2) {
                        if ((intrnames = reallocf(intrnames, inamlen)) == NULL)
                                xo_err(1, "reallocf()");
                        if (mysysctl("hw.intrnames", intrnames, &inamlen) == 0)
                                break;
                }
        }

        /* Determine the length of the longest interrupt name */
        intrname = intrnames;
        istrnamlen = strlen("interrupt");
        while (intrname < intrnames + inamlen) {
                clen = strlen(intrname);
                if (clen > istrnamlen)
                        istrnamlen = clen;
                intrname += strlen(intrname) + 1;
        }
        xo_emit("{T:/%-*s} {T:/%20s} {T:/%10s}\n",
            (int)istrnamlen, "interrupt", "total", "rate");

        /* 
         * Loop reps times printing differential interrupt counts.  If reps is
         * zero, then run just once, printing total counts
         */
        xo_open_container("interrupt-statistics");

        period_ms = uptime / 1000000;
        while(1) {
                nintr = read_intrcnts(&intrcnts);
                /* 
                 * Initialize old_intrcnts to 0 for the first pass, so
                 * print_intrcnts will print total interrupts since boot
                 */
                if (old_intrcnts == NULL) {
                        old_intrcnts = calloc(nintr, sizeof(unsigned long));
                        if (old_intrcnts == NULL)
                                xo_err(1, "calloc()");
                }

                print_intrcnts(intrcnts, old_intrcnts, intrnames, nintr,
                    istrnamlen, period_ms);
                if (xo_flush() < 0)
                        xo_err(EXIT_FAILURE, "stdout");

                free(old_intrcnts);
                old_intrcnts = intrcnts;
                if (reps >= 0 && --reps <= 0)
                        break;
                usleep(interval * 1000);
                old_uptime = uptime;
                uptime = getuptime();
                period_ms = (uptime - old_uptime) / 1000000;
        }

        xo_close_container("interrupt-statistics");
}

static void
domemstat_malloc(void)
{
        struct memory_type_list *mtlp;
        struct memory_type *mtp;
        size_t i, zones;
        int error, first;

        mtlp = memstat_mtl_alloc();
        if (mtlp == NULL) {
                xo_warn("memstat_mtl_alloc");
                return;
        }
        if (kd == NULL) {
                if (memstat_sysctl_malloc(mtlp, 0) < 0) {
                        xo_warnx("memstat_sysctl_malloc: %s",
                            memstat_strerror(memstat_mtl_geterror(mtlp)));
                        return;
                }
        } else {
                if (memstat_kvm_malloc(mtlp, kd) < 0) {
                        error = memstat_mtl_geterror(mtlp);
                        if (error == MEMSTAT_ERROR_KVM)
                                xo_warnx("memstat_kvm_malloc: %s",
                                    kvm_geterr(kd));
                        else
                                xo_warnx("memstat_kvm_malloc: %s",
                                    memstat_strerror(error));
                }
        }
        xo_open_container("malloc-statistics");
        xo_emit("{T:/%16s} {T:/%4s} {T:/%5s} {T:/%3s} {T:Size(s)}\n",
            "Type", "Use", "Memory", "Req");
        xo_open_list("memory");
        zones = memstat_malloc_zone_get_count();
        for (mtp = memstat_mtl_first(mtlp); mtp != NULL;
            mtp = memstat_mtl_next(mtp)) {
                if (memstat_get_numallocs(mtp) == 0 &&
                    memstat_get_count(mtp) == 0)
                        continue;
                xo_open_instance("memory");
                xo_emit("{k:type/%16s/%s} "
                    "{[:4}{h,hn-decimal,hn-1000:in-use/%ju}{]:} "
                    "{[:5}{h,hn-decimal:memory-use/%ju}{]:} "
                    "{[:4}{h,hn-decimal,hn-1000:requests/%ju}{]:} ",
                    memstat_get_name(mtp), (uintmax_t)memstat_get_count(mtp),
                    (uintmax_t)memstat_get_bytes(mtp),
                    (uintmax_t)memstat_get_numallocs(mtp));
                first = 1;
                xo_open_list("size");
                for (i = 0; i < zones; i++) {
                        if (memstat_malloc_zone_used(mtp, i)) {
                                if (!first)
                                        xo_emit(",");
                                xo_emit("{lh:size/%d}", memstat_malloc_zone_get_size(i));
                                first = 0;
                        }
                }
                xo_close_list("size");
                xo_close_instance("memory");
                xo_emit("\n");
        }
        xo_close_list("memory");
        xo_close_container("malloc-statistics");
        memstat_mtl_free(mtlp);
}

static void
domemstat_zone(void)
{
        struct memory_type_list *mtlp;
        struct memory_type *mtp;
        int error, len;

        mtlp = memstat_mtl_alloc();
        if (mtlp == NULL) {
                xo_warn("memstat_mtl_alloc");
                return;
        }
        if (kd == NULL) {
                if (memstat_sysctl_uma(mtlp, 0) < 0) {
                        xo_warnx("memstat_sysctl_uma: %s",
                            memstat_strerror(memstat_mtl_geterror(mtlp)));
                        return;
                }
        } else {
                if (memstat_kvm_uma(mtlp, kd) < 0) {
                        error = memstat_mtl_geterror(mtlp);
                        if (error == MEMSTAT_ERROR_KVM)
                                xo_warnx("memstat_kvm_uma: %s",
                                    kvm_geterr(kd));
                        else
                                xo_warnx("memstat_kvm_uma: %s",
                                    memstat_strerror(error));
                }
        }
        xo_open_container("memory-zone-statistics");
        xo_emit("{T:/%-19s} {T:/%7s} {T:/%7s} {T:/%8s} {T:/%8s} {T:/%8s} "
            "{T:/%4s} {T:/%4s} {T:/%4s}\n", "ITEM", "SIZE",
            "LIMIT", "USED", "FREE", "REQ", "FAIL", "SLEEP", "XDOM");
        xo_open_list("zone");
        for (mtp = memstat_mtl_first(mtlp); mtp != NULL;
            mtp = memstat_mtl_next(mtp)) {
                len = strlen(memstat_get_name(mtp));
                xo_open_instance("zone");
                xo_emit("{k:name/%s}:{d:size/%*ju}{e:size/%ju},"
                    "{:limit/%7ju},{:used/%8ju},"
                    "{:free/%8ju},{:requests/%8ju},"
                    "{:fail/%4ju},{:sleep/%4ju},{:xdomain/%4ju}\n",
                    memstat_get_name(mtp), MAX(1, 26 - len),
                    (uintmax_t)memstat_get_size(mtp),
                    (uintmax_t)memstat_get_size(mtp),
                    (uintmax_t)memstat_get_countlimit(mtp),
                    (uintmax_t)memstat_get_count(mtp),
                    (uintmax_t)memstat_get_free(mtp),
                    (uintmax_t)memstat_get_numallocs(mtp),
                    (uintmax_t)memstat_get_failures(mtp),
                    (uintmax_t)memstat_get_sleeps(mtp),
                    (uintmax_t)memstat_get_xdomain(mtp));
                xo_close_instance("zone");
        }
        memstat_mtl_free(mtlp);
        xo_close_list("zone");
        xo_close_container("memory-zone-statistics");
}

static void
display_object(struct kinfo_vmobject *kvo)
{
        const char *str;

        xo_open_instance("object");
        xo_emit("{:resident/%5ju} ", (uintmax_t)kvo->kvo_resident);
        xo_emit("{:active/%5ju} ", (uintmax_t)kvo->kvo_active);
        xo_emit("{:inactive/%5ju} ", (uintmax_t)kvo->kvo_inactive);
        xo_emit("{:laundry/%5ju} ", (uintmax_t)kvo->kvo_laundry);
        xo_emit("{:wired/%5ju} ", (uintmax_t)kvo->kvo_wired);
        xo_emit("{:refcount/%3d} ", kvo->kvo_ref_count);
        xo_emit("{:shadowcount/%3d} ", kvo->kvo_shadow_count);

#define MEMATTR_STR(type, val)                                  \
        if (kvo->kvo_memattr == (type)) {                       \
                str = (val);                                    \
        } else
#ifdef VM_MEMATTR_UNCACHEABLE
        MEMATTR_STR(VM_MEMATTR_UNCACHEABLE, "UC")
#endif
#ifdef VM_MEMATTR_WRITE_COMBINING
        MEMATTR_STR(VM_MEMATTR_WRITE_COMBINING, "WC")
#endif
#ifdef VM_MEMATTR_WRITE_THROUGH
        MEMATTR_STR(VM_MEMATTR_WRITE_THROUGH, "WT")
#endif
#ifdef VM_MEMATTR_WRITE_PROTECTED
        MEMATTR_STR(VM_MEMATTR_WRITE_PROTECTED, "WP")
#endif
#ifdef VM_MEMATTR_WRITE_BACK
        MEMATTR_STR(VM_MEMATTR_WRITE_BACK, "WB")
#endif
#ifdef VM_MEMATTR_WEAK_UNCACHEABLE
        MEMATTR_STR(VM_MEMATTR_WEAK_UNCACHEABLE, "UC-")
#endif
#ifdef VM_MEMATTR_WB_WA
        MEMATTR_STR(VM_MEMATTR_WB_WA, "WB")
#endif
#ifdef VM_MEMATTR_NOCACHE
        MEMATTR_STR(VM_MEMATTR_NOCACHE, "NC")
#endif
#ifdef VM_MEMATTR_DEVICE
        MEMATTR_STR(VM_MEMATTR_DEVICE, "DEV")
#endif
#ifdef VM_MEMATTR_DEVICE_NP
        MEMATTR_STR(VM_MEMATTR_DEVICE, "NP")
#endif
#ifdef VM_MEMATTR_CACHEABLE
        MEMATTR_STR(VM_MEMATTR_CACHEABLE, "C")
#endif
#ifdef VM_MEMATTR_PREFETCHABLE
        MEMATTR_STR(VM_MEMATTR_PREFETCHABLE, "PRE")
#endif
        {
                str = "??";
        }
#undef MEMATTR_STR
        xo_emit("{:attribute/%-3s} ", str);
        switch (kvo->kvo_type) {
        case KVME_TYPE_NONE:
                str = "--";
                break;
        case KVME_TYPE_DEFAULT:
                str = "df";
                break;
        case KVME_TYPE_VNODE:
                str = "vn";
                break;
        case KVME_TYPE_SWAP:
                str = "sw";
                break;
        case KVME_TYPE_DEVICE:
                str = "dv";
                break;
        case KVME_TYPE_PHYS:
                str = "ph";
                break;
        case KVME_TYPE_DEAD:
                str = "dd";
                break;
        case KVME_TYPE_SG:
                str = "sg";
                break;
        case KVME_TYPE_MGTDEVICE:
                str = "md";
                break;
        case KVME_TYPE_UNKNOWN:
        default:
                str = "??";
                break;
        }
        xo_emit("{:type/%-2s} ", str);
        if ((kvo->kvo_flags & KVMO_FLAG_SYSVSHM) != 0)
                xo_emit("{:sysvshm/sysvshm(%ju:%u)} ",
                    (uintmax_t)kvo->kvo_vn_fileid, kvo->kvo_vn_fsid_freebsd11);
        if ((kvo->kvo_flags & KVMO_FLAG_POSIXSHM) != 0)
                xo_emit("{:posixshm/posixshm@/posixshm}");
        xo_emit("{:path/%-s}\n", kvo->kvo_path);
        xo_close_instance("object");
}

static void
doobjstat(void)
{
        struct kinfo_vmobject *kvo;
        int cnt, i;

        kvo = kinfo_getvmobject(&cnt);
        if (kvo == NULL) {
                xo_warn("Failed to fetch VM object list");
                return;
        }
        xo_emit("{T:RES/%5s} {T:ACT/%5s} {T:INACT/%5s} {T:LAUND/%5s} "
            "{T:WIRED/%5s} {T:REF/%3s} {T:SHD/%3s} {T:CM/%2s} {T:TP/%3s} "
            "{T:PATH/%s}\n");
        xo_open_list("object");
        for (i = 0; i < cnt; i++)
                display_object(&kvo[i]);
        free(kvo);
        xo_close_list("object");
}

/*
 * kread reads something from the kernel, given its nlist index.
 */
static void
kreado(int nlx, void *addr, size_t size, size_t offset)
{
        const char *sym;

        if (namelist[nlx].n_type == 0 || namelist[nlx].n_value == 0) {
                sym = namelist[nlx].n_name;
                if (*sym == '_')
                        ++sym;
                xo_errx(1, "symbol %s not defined", sym);
        }
        if ((size_t)kvm_read(kd, namelist[nlx].n_value + offset, addr,
            size) != size) {
                sym = namelist[nlx].n_name;
                if (*sym == '_')
                        ++sym;
                xo_errx(1, "%s: %s", sym, kvm_geterr(kd));
        }
}

static void
kread(int nlx, void *addr, size_t size)
{

        kreado(nlx, addr, size, 0);
}

static void
kreadptr(uintptr_t addr, void *buf, size_t size)
{

        if ((size_t)kvm_read(kd, addr, buf, size) != size)
                xo_errx(1, "%s", kvm_geterr(kd));
}

static void __dead2
usage(void)
{
        xo_error("%s%s",
            "usage: vmstat [-afHhimoPsz] [-M core [-N system]] [-c count] [-n devs]\n",
            "              [-p type,if,pass] [-w wait] [disks] [wait [count]]\n");
        if (xo_finish() < 0)
                xo_err(EXIT_FAILURE, "stdout");
        exit(EXIT_FAILURE);
}