freebsd-dev/usr.sbin/pstat/pstat.c
Ed Schouten c0086bf202 Serialize write() calls on TTYs.
Just like the old TTY layer, the current MPSAFE TTY layer does not make
any attempt to serialize calls of write(). Data is copied into the
kernel in 256 (TTY_STACKBUF) byte chunks. If a write() call occurs at
the same time, the data may interleave. This is especially likely when
the TTY starts blocking, because the output queue reaches the high
watermark.

I've implemented this by adding a new flag, TTY_BUSY_OUT, which is used
to mark a TTY as having a thread stuck in write(). Because I don't want
non-blocking processes to be possibly blocked by a sleeping thread, I'm
still allowing it to bypass the protection. According to this message,
the Linux kernel returns EAGAIN in such cases, but I think that's a
little too restrictive:

	http://kerneltrap.org/index.php?q=mailarchive/linux-kernel/2007/5/2/85418/thread

PR:		kern/118287
2009-02-11 16:28:49 +00:00

585 lines
14 KiB
C

/*-
* Copyright (c) 1980, 1991, 1993, 1994
* The Regents of the University of California. All rights reserved.
* Copyright (c) 2002 Networks Associates Technologies, Inc.
* All rights reserved.
*
* Portions of this software were developed for the FreeBSD Project by
* ThinkSec AS and NAI Labs, the Security Research Division of Network
* Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035
* ("CBOSS"), as part of the DARPA CHATS research program.
*
* 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.
* 4. 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.
*/
#if 0
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1980, 1991, 1993, 1994\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
static char sccsid[] = "@(#)pstat.c 8.16 (Berkeley) 5/9/95";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/time.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/stdint.h>
#include <sys/ioctl.h>
#include <sys/tty.h>
#include <sys/blist.h>
#include <sys/sysctl.h>
#include <vm/vm_param.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <kvm.h>
#include <libutil.h>
#include <limits.h>
#include <nlist.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
enum {
NL_CONSTTY,
NL_MAXFILES,
NL_NFILES,
NL_TTY_LIST
};
static struct nlist nl[] = {
{ .n_name = "_constty" },
{ .n_name = "_maxfiles" },
{ .n_name = "_openfiles" },
{ .n_name = "_tty_list" },
{ .n_name = "" }
};
static int humanflag;
static int usenumflag;
static int totalflag;
static int swapflag;
static char *nlistf;
static char *memf;
static kvm_t *kd;
static char *usagestr;
static void filemode(void);
static int getfiles(char **, size_t *);
static void swapmode(void);
static void ttymode(void);
static void ttyprt(struct xtty *);
static void usage(void);
int
main(int argc, char *argv[])
{
int ch, i, quit, ret;
int fileflag, ttyflag;
char buf[_POSIX2_LINE_MAX],*opts;
fileflag = swapflag = ttyflag = 0;
/* We will behave like good old swapinfo if thus invoked */
opts = strrchr(argv[0], '/');
if (opts)
opts++;
else
opts = argv[0];
if (!strcmp(opts, "swapinfo")) {
swapflag = 1;
opts = "ghkmM:N:";
usagestr = "swapinfo [-ghkm] [-M core [-N system]]";
} else {
opts = "TM:N:fghkmnst";
usagestr = "pstat [-Tfghkmnst] [-M core [-N system]]";
}
while ((ch = getopt(argc, argv, opts)) != -1)
switch (ch) {
case 'f':
fileflag = 1;
break;
case 'g':
setenv("BLOCKSIZE", "1G", 1);
break;
case 'h':
humanflag = 1;
break;
case 'k':
setenv("BLOCKSIZE", "1K", 1);
break;
case 'm':
setenv("BLOCKSIZE", "1M", 1);
break;
case 'M':
memf = optarg;
break;
case 'N':
nlistf = optarg;
break;
case 'n':
usenumflag = 1;
break;
case 's':
++swapflag;
break;
case 'T':
totalflag = 1;
break;
case 't':
ttyflag = 1;
break;
default:
usage();
}
argc -= optind;
argv += optind;
if (memf != NULL) {
kd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, buf);
if (kd == NULL)
errx(1, "kvm_openfiles: %s", buf);
if ((ret = kvm_nlist(kd, nl)) != 0) {
if (ret == -1)
errx(1, "kvm_nlist: %s", kvm_geterr(kd));
quit = 0;
for (i = 0; nl[i].n_name[0] != '\0'; ++i)
if (nl[i].n_value == 0) {
quit = 1;
warnx("undefined symbol: %s",
nl[i].n_name);
}
if (quit)
exit(1);
}
}
if (!(fileflag | ttyflag | swapflag | totalflag))
usage();
if (fileflag || totalflag)
filemode();
if (ttyflag)
ttymode();
if (swapflag || totalflag)
swapmode();
exit (0);
}
static void
usage(void)
{
fprintf(stderr, "usage: %s\n", usagestr);
exit (1);
}
static const char fhdr32[] =
" LOC TYPE FLG CNT MSG DATA OFFSET\n";
/* c0000000 ------ RWAI 123 123 c0000000 1000000000000000 */
static const char fhdr64[] =
" LOC TYPE FLG CNT MSG DATA OFFSET\n";
/* c000000000000000 ------ RWAI 123 123 c000000000000000 1000000000000000 */
static const char hdr[] =
" LINE INQ CAN LIN LOW OUTQ USE LOW COL SESS PGID STATE\n";
static void
ttymode_kvm(void)
{
TAILQ_HEAD(, tty) tl;
struct tty *tp, tty;
struct xtty xt;
(void)printf("%s", hdr);
bzero(&xt, sizeof xt);
xt.xt_size = sizeof xt;
if (kvm_read(kd, nl[NL_TTY_LIST].n_value, &tl, sizeof tl) != sizeof tl)
errx(1, "kvm_read(): %s", kvm_geterr(kd));
tp = TAILQ_FIRST(&tl);
while (tp != NULL) {
if (kvm_read(kd, (u_long)tp, &tty, sizeof tty) != sizeof tty)
errx(1, "kvm_read(): %s", kvm_geterr(kd));
xt.xt_insize = tty.t_inq.ti_nblocks * TTYINQ_DATASIZE;
xt.xt_incc = tty.t_inq.ti_linestart - tty.t_inq.ti_begin;
xt.xt_inlc = tty.t_inq.ti_end - tty.t_inq.ti_linestart;
xt.xt_inlow = tty.t_inlow;
xt.xt_outsize = tty.t_outq.to_nblocks * TTYOUTQ_DATASIZE;
xt.xt_outcc = tty.t_outq.to_end - tty.t_outq.to_begin;
xt.xt_outlow = tty.t_outlow;
xt.xt_column = tty.t_column;
/* xt.xt_pgid = ... */
/* xt.xt_sid = ... */
xt.xt_flags = tty.t_flags;
xt.xt_dev = NODEV;
ttyprt(&xt);
tp = TAILQ_NEXT(&tty, t_list);
}
}
static void
ttymode_sysctl(void)
{
struct xtty *xt, *end;
void *xttys;
size_t len;
(void)printf("%s", hdr);
if ((xttys = malloc(len = sizeof *xt)) == NULL)
err(1, "malloc()");
while (sysctlbyname("kern.ttys", xttys, &len, 0, 0) == -1) {
if (errno != ENOMEM)
err(1, "sysctlbyname()");
len *= 2;
if ((xttys = realloc(xttys, len)) == NULL)
err(1, "realloc()");
}
if (len > 0) {
end = (struct xtty *)((char *)xttys + len);
for (xt = xttys; xt < end; xt++)
ttyprt(xt);
}
}
static void
ttymode(void)
{
if (kd != NULL)
ttymode_kvm();
else
ttymode_sysctl();
}
static struct {
int flag;
char val;
} ttystates[] = {
#if 0
{ TF_NOPREFIX, 'N' },
#endif
{ TF_INITLOCK, 'I' },
{ TF_CALLOUT, 'C' },
/* Keep these together -> 'Oi' and 'Oo'. */
{ TF_OPENED, 'O' },
{ TF_OPENED_IN, 'i' },
{ TF_OPENED_OUT, 'o' },
{ TF_OPENED_CONS, 'c' },
{ TF_GONE, 'G' },
{ TF_OPENCLOSE, 'B' },
{ TF_ASYNC, 'Y' },
{ TF_LITERAL, 'L' },
/* Keep these together -> 'Hi' and 'Ho'. */
{ TF_HIWAT, 'H' },
{ TF_HIWAT_IN, 'i' },
{ TF_HIWAT_OUT, 'o' },
{ TF_STOPPED, 'S' },
{ TF_EXCLUDE, 'X' },
{ TF_BYPASS, 'l' },
{ TF_ZOMBIE, 'Z' },
{ TF_HOOK, 's' },
/* Keep these together -> 'bi' and 'bo'. */
{ TF_BUSY, 'b' },
{ TF_BUSY_IN, 'i' },
{ TF_BUSY_OUT, 'o' },
{ 0, '\0'},
};
static void
ttyprt(struct xtty *xt)
{
int i, j;
char *name;
if (xt->xt_size != sizeof *xt)
errx(1, "struct xtty size mismatch");
if (usenumflag || xt->xt_dev == 0 ||
(name = devname(xt->xt_dev, S_IFCHR)) == NULL)
printf("%5d,%4d ", major(xt->xt_dev), minor(xt->xt_dev));
else
printf("%10s ", name);
printf("%5zu %4zu %4zu %4zu %5zu %4zu %4zu %5u %5d %5d ",
xt->xt_insize, xt->xt_incc, xt->xt_inlc,
(xt->xt_insize - xt->xt_inlow), xt->xt_outsize,
xt->xt_outcc, (xt->xt_outsize - xt->xt_outlow),
MIN(xt->xt_column, 99999), xt->xt_sid, xt->xt_pgid);
for (i = j = 0; ttystates[i].flag; i++)
if (xt->xt_flags & ttystates[i].flag) {
putchar(ttystates[i].val);
j++;
}
if (j == 0)
putchar('-');
putchar('\n');
}
static void
filemode(void)
{
struct xfile *fp;
char *buf, flagbuf[16], *fbp;
int maxf, openf;
size_t len;
static char *dtypes[] = { "???", "inode", "socket", "pipe",
"fifo", "kqueue", "crypto" };
int i;
int wid;
if (kd != NULL) {
if (kvm_read(kd, nl[NL_MAXFILES].n_value,
&maxf, sizeof maxf) != sizeof maxf ||
kvm_read(kd, nl[NL_NFILES].n_value,
&openf, sizeof openf) != sizeof openf)
errx(1, "kvm_read(): %s", kvm_geterr(kd));
} else {
len = sizeof(int);
if (sysctlbyname("kern.maxfiles", &maxf, &len, 0, 0) == -1 ||
sysctlbyname("kern.openfiles", &openf, &len, 0, 0) == -1)
err(1, "sysctlbyname()");
}
if (totalflag) {
(void)printf("%3d/%3d files\n", openf, maxf);
return;
}
if (getfiles(&buf, &len) == -1)
return;
openf = len / sizeof *fp;
(void)printf("%d/%d open files\n", openf, maxf);
printf(sizeof(uintptr_t) == 4 ? fhdr32 : fhdr64);
wid = (int)sizeof(uintptr_t) * 2;
for (fp = (struct xfile *)buf, i = 0; i < openf; ++fp, ++i) {
if ((size_t)fp->xf_type >= sizeof(dtypes) / sizeof(dtypes[0]))
continue;
(void)printf("%*jx", wid, (uintmax_t)(uintptr_t)fp->xf_file);
(void)printf(" %-6.6s", dtypes[fp->xf_type]);
fbp = flagbuf;
if (fp->xf_flag & FREAD)
*fbp++ = 'R';
if (fp->xf_flag & FWRITE)
*fbp++ = 'W';
if (fp->xf_flag & FAPPEND)
*fbp++ = 'A';
if (fp->xf_flag & FASYNC)
*fbp++ = 'I';
*fbp = '\0';
(void)printf(" %4s %3d", flagbuf, fp->xf_count);
(void)printf(" %3d", fp->xf_msgcount);
(void)printf(" %*jx", wid, (uintmax_t)(uintptr_t)fp->xf_data);
(void)printf(" %*jx\n", (int)sizeof(fp->xf_offset) * 2,
(uintmax_t)fp->xf_offset);
}
free(buf);
}
static int
getfiles(char **abuf, size_t *alen)
{
size_t len;
int mib[2];
char *buf;
/*
* XXX
* Add emulation of KINFO_FILE here.
*/
if (kd != NULL)
errx(1, "files on dead kernel, not implemented");
mib[0] = CTL_KERN;
mib[1] = KERN_FILE;
if (sysctl(mib, 2, NULL, &len, NULL, 0) == -1) {
warn("sysctl: KERN_FILE");
return (-1);
}
if ((buf = malloc(len)) == NULL)
errx(1, "malloc");
if (sysctl(mib, 2, buf, &len, NULL, 0) == -1) {
warn("sysctl: KERN_FILE");
return (-1);
}
*abuf = buf;
*alen = len;
return (0);
}
/*
* swapmode is based on a program called swapinfo written
* by Kevin Lahey <kml@rokkaku.atl.ga.us>.
*/
#define CONVERT(v) ((int64_t)(v) * pagesize / blocksize)
static struct kvm_swap swtot;
static int nswdev;
static void
print_swap_header(void)
{
int hlen;
long blocksize;
const char *header;
header = getbsize(&hlen, &blocksize);
if (totalflag == 0)
(void)printf("%-15s %*s %8s %8s %8s\n",
"Device", hlen, header,
"Used", "Avail", "Capacity");
}
static void
print_swap_line(const char *devname, intmax_t nblks, intmax_t bused,
intmax_t bavail, float bpercent)
{
char usedbuf[5];
char availbuf[5];
int hlen, pagesize;
long blocksize;
pagesize = getpagesize();
getbsize(&hlen, &blocksize);
printf("%-15s %*jd ", devname, hlen, CONVERT(nblks));
if (humanflag) {
humanize_number(usedbuf, sizeof(usedbuf),
CONVERT(blocksize * bused), "",
HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
humanize_number(availbuf, sizeof(availbuf),
CONVERT(blocksize * bavail), "",
HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
printf("%8s %8s %5.0f%%\n", usedbuf, availbuf, bpercent);
} else {
printf("%8jd %8jd %5.0f%%\n", (intmax_t)CONVERT(bused),
(intmax_t)CONVERT(bavail), bpercent);
}
}
static void
print_swap(struct kvm_swap *ksw)
{
swtot.ksw_total += ksw->ksw_total;
swtot.ksw_used += ksw->ksw_used;
++nswdev;
if (totalflag == 0)
print_swap_line(ksw->ksw_devname, ksw->ksw_total,
ksw->ksw_used, ksw->ksw_total - ksw->ksw_used,
(ksw->ksw_used * 100.0) / ksw->ksw_total);
}
static void
print_swap_total(void)
{
int hlen, pagesize;
long blocksize;
pagesize = getpagesize();
getbsize(&hlen, &blocksize);
if (totalflag) {
blocksize = 1024 * 1024;
(void)printf("%jdM/%jdM swap space\n",
CONVERT(swtot.ksw_used), CONVERT(swtot.ksw_total));
} else if (nswdev > 1) {
print_swap_line("Total", swtot.ksw_total, swtot.ksw_used,
swtot.ksw_total - swtot.ksw_used,
(swtot.ksw_used * 100.0) / swtot.ksw_total);
}
}
static void
swapmode_kvm(void)
{
struct kvm_swap kswap[16];
int i, n;
n = kvm_getswapinfo(kd, kswap, sizeof kswap / sizeof kswap[0],
SWIF_DEV_PREFIX);
print_swap_header();
for (i = 0; i < n; ++i)
print_swap(&kswap[i]);
print_swap_total();
}
static void
swapmode_sysctl(void)
{
struct kvm_swap ksw;
struct xswdev xsw;
size_t mibsize, size;
int mib[16], n;
print_swap_header();
mibsize = sizeof mib / sizeof mib[0];
if (sysctlnametomib("vm.swap_info", mib, &mibsize) == -1)
err(1, "sysctlnametomib()");
for (n = 0; ; ++n) {
mib[mibsize] = n;
size = sizeof xsw;
if (sysctl(mib, mibsize + 1, &xsw, &size, NULL, 0) == -1)
break;
if (xsw.xsw_version != XSWDEV_VERSION)
errx(1, "xswdev version mismatch");
if (xsw.xsw_dev == NODEV)
snprintf(ksw.ksw_devname, sizeof ksw.ksw_devname,
"<NFSfile>");
else
snprintf(ksw.ksw_devname, sizeof ksw.ksw_devname,
"/dev/%s", devname(xsw.xsw_dev, S_IFCHR));
ksw.ksw_used = xsw.xsw_used;
ksw.ksw_total = xsw.xsw_nblks;
ksw.ksw_flags = xsw.xsw_flags;
print_swap(&ksw);
}
if (errno != ENOENT)
err(1, "sysctl()");
print_swap_total();
}
static void
swapmode(void)
{
if (kd != NULL)
swapmode_kvm();
else
swapmode_sysctl();
}