freebsd-skq/usr.bin/systat/mbufs.c
Bosko Milekic 099a0e588c Bring in mbuma to replace mballoc.
mbuma is an Mbuf & Cluster allocator built on top of a number of
extensions to the UMA framework, all included herein.

Extensions to UMA worth noting:
  - Better layering between slab <-> zone caches; introduce
    Keg structure which splits off slab cache away from the
    zone structure and allows multiple zones to be stacked
    on top of a single Keg (single type of slab cache);
    perhaps we should look into defining a subset API on
    top of the Keg for special use by malloc(9),
    for example.
  - UMA_ZONE_REFCNT zones can now be added, and reference
    counters automagically allocated for them within the end
    of the associated slab structures.  uma_find_refcnt()
    does a kextract to fetch the slab struct reference from
    the underlying page, and lookup the corresponding refcnt.

mbuma things worth noting:
  - integrates mbuf & cluster allocations with extended UMA
    and provides caches for commonly-allocated items; defines
    several zones (two primary, one secondary) and two kegs.
  - change up certain code paths that always used to do:
    m_get() + m_clget() to instead just use m_getcl() and
    try to take advantage of the newly defined secondary
    Packet zone.
  - netstat(1) and systat(1) quickly hacked up to do basic
    stat reporting but additional stats work needs to be
    done once some other details within UMA have been taken
    care of and it becomes clearer to how stats will work
    within the modified framework.

From the user perspective, one implication is that the
NMBCLUSTERS compile-time option is no longer used.  The
maximum number of clusters is still capped off according
to maxusers, but it can be made unlimited by setting
the kern.ipc.nmbclusters boot-time tunable to zero.
Work should be done to write an appropriate sysctl
handler allowing dynamic tuning of kern.ipc.nmbclusters
at runtime.

Additional things worth noting/known issues (READ):
   - One report of 'ips' (ServeRAID) driver acting really
     slow in conjunction with mbuma.  Need more data.
     Latest report is that ips is equally sucking with
     and without mbuma.
   - Giant leak in NFS code sometimes occurs, can't
     reproduce but currently analyzing; brueffer is
     able to reproduce but THIS IS NOT an mbuma-specific
     problem and currently occurs even WITHOUT mbuma.
   - Issues in network locking: there is at least one
     code path in the rip code where one or more locks
     are acquired and we end up in m_prepend() with
     M_WAITOK, which causes WITNESS to whine from within
     UMA.  Current temporary solution: force all UMA
     allocations to be M_NOWAIT from within UMA for now
     to avoid deadlocks unless WITNESS is defined and we
     can determine with certainty that we're not holding
     any locks when we're M_WAITOK.
   - I've seen at least one weird socketbuffer empty-but-
     mbuf-still-attached panic.  I don't believe this
     to be related to mbuma but please keep your eyes
     open, turn on debugging, and capture crash dumps.

This change removes more code than it adds.

A paper is available detailing the change and considering
various performance issues, it was presented at BSDCan2004:
http://www.unixdaemons.com/~bmilekic/netbuf_bmilekic.pdf
Please read the paper for Future Work and implementation
details, as well as credits.

Testing and Debugging:
    rwatson,
    brueffer,
    Ketrien I. Saihr-Kesenchedra,
    ...
Reviewed by: Lots of people (for different parts)
2004-05-31 21:46:06 +00:00

201 lines
4.7 KiB
C

/*-
* Copyright (c) 1980, 1992, 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#ifdef lint
static const char sccsid[] = "@(#)mbufs.c 8.1 (Berkeley) 6/6/93";
#endif
#include <sys/param.h>
#include <sys/types.h>
#include <sys/mbuf.h>
#include <sys/sysctl.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <paths.h>
#include "systat.h"
#include "extern.h"
static struct mbstat *mbstat;
static long *m_mbtypes;
static short nmbtypes;
static struct mtnames {
short mt_type;
const char *mt_name;
} mtnames[] = {
{ MT_DATA, "data"},
{ MT_HEADER, "headers"},
{ MT_SONAME, "socknames"},
{ MT_FTABLE, "frags"},
{ MT_CONTROL, "control"},
{ MT_OOBDATA, "oobdata"}
};
#define NNAMES (sizeof (mtnames) / sizeof (mtnames[0]))
WINDOW *
openmbufs()
{
return (subwin(stdscr, LINES-5-1, 0, 5, 0));
}
void
closembufs(w)
WINDOW *w;
{
if (w == NULL)
return;
wclear(w);
wrefresh(w);
delwin(w);
}
void
labelmbufs()
{
wmove(wnd, 0, 0); wclrtoeol(wnd);
mvwaddstr(wnd, 0, 10,
"/0 /5 /10 /15 /20 /25 /30 /35 /40 /45 /50 /55 /60");
}
void
showmbufs()
{
int i, j, max, idx;
u_long totmbufs;
char buf[10];
const char *mtname;
totmbufs = mbstat->m_mbufs;
/*
* Print totals for different mbuf types.
*/
for (j = 0; j < wnd->_maxy; j++) {
max = 0, idx = -1;
for (i = 0; i < wnd->_maxy; i++) {
if (i == MT_NOTMBUF)
continue;
if (i >= nmbtypes)
break;
if (m_mbtypes[i] > max) {
max = m_mbtypes[i];
idx = i;
}
}
if (max == 0)
break;
mtname = NULL;
for (i = 0; i < (int)NNAMES; i++)
if (mtnames[i].mt_type == idx)
mtname = mtnames[i].mt_name;
if (mtname == NULL)
mvwprintw(wnd, 1+j, 0, "%10d", idx);
else
mvwprintw(wnd, 1+j, 0, "%-10.10s", mtname);
wmove(wnd, 1 + j, 10);
if (max > 60) {
snprintf(buf, sizeof(buf), " %d", max);
max = 60;
while (max--)
waddch(wnd, 'X');
waddstr(wnd, buf);
} else
while (max--)
waddch(wnd, 'X');
wclrtoeol(wnd);
m_mbtypes[idx] = 0;
}
/*
* Print total number of free mbufs.
*/
if (totmbufs > 0) {
mvwprintw(wnd, 1+j, 0, "%-10.10s", "Mbufs");
if (totmbufs > 60) {
snprintf(buf, sizeof(buf), " %lu", totmbufs);
totmbufs = 60;
while(totmbufs--)
waddch(wnd, 'X');
waddstr(wnd, buf);
} else {
while(totmbufs--)
waddch(wnd, 'X');
}
wclrtoeol(wnd);
j++;
}
wmove(wnd, 1+j, 0); wclrtobot(wnd);
}
int
initmbufs()
{
int i;
size_t len;
len = sizeof *mbstat;
if ((mbstat = malloc(len)) == NULL) {
error("malloc mbstat failed");
return 0;
}
if (sysctlbyname("kern.ipc.mbstat", mbstat, &len, NULL, 0) < 0) {
error("sysctl retrieving mbstat");
return 0;
}
nmbtypes = mbstat->m_numtypes;
if ((m_mbtypes = calloc(nmbtypes, sizeof(long *))) == NULL) {
error("calloc m_mbtypes failed");
return 0;
}
return 1;
}
void
fetchmbufs()
{
size_t len;
len = sizeof *mbstat;
if (sysctlbyname("kern.ipc.mbstat", mbstat, &len, NULL, 0) < 0)
printw("sysctl: mbstat: %s", strerror(errno));
}