NetBSD/usr.bin/systat/bufcache.c

371 lines
8.8 KiB
C

/* $NetBSD: bufcache.c,v 1.5 1999/12/20 23:11:50 jwise Exp $ */
/*-
* Copyright (c) 1999 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Simon Burge.
*
* 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 NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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>
#ifndef lint
__RCSID("$NetBSD: bufcache.c,v 1.5 1999/12/20 23:11:50 jwise Exp $");
#endif /* not lint */
#include <sys/param.h>
#include <sys/buf.h>
#include <sys/mount.h>
#include <sys/queue.h>
#include <sys/time.h>
#include <sys/vnode.h>
#include <err.h>
#include <kvm.h>
#include <nlist.h>
#include <paths.h>
#include <stdlib.h>
#include <unistd.h>
#include "systat.h"
#include "extern.h"
/*
* Definitions for the buffer free lists (from sys/kern/vfs_bio.c).
*/
#define BQUEUES 4 /* number of free buffer queues */
#define BQ_LOCKED 0 /* super-blocks &c */
#define BQ_LRU 1 /* lru, useful buffers */
#define BQ_AGE 2 /* rubbish */
#define BQ_EMPTY 3 /* buffer headers with no memory */
#define VCACHE_SIZE 50
struct vcache {
int vc_age;
struct vnode *vc_addr;
struct vnode vc_node;
};
struct ml_entry {
int ml_count;
long ml_size;
long ml_valid;
struct mount *ml_addr;
struct mount ml_mount;
LIST_ENTRY(ml_entry) ml_entries;
};
static struct nlist namelist[] = {
#define X_NBUF 0
{ "_nbuf" },
#define X_BUF 1
{ "_buf" },
#define X_BUFQUEUES 2
{ "_bufqueues" },
#define X_BUFPAGES 3
{ "_bufpages" },
{ "" },
};
static struct vcache vcache[VCACHE_SIZE];
static LIST_HEAD(mount_list, ml_entry) mount_list;
static int nbuf, bufpages, bufbytes;
static void *bufaddr;
static struct buf *buf = NULL;
static TAILQ_HEAD(bqueues, buf) bufqueues[BQUEUES];
static void vc_init __P((void));
static void ml_init __P((void));
static struct vnode *vc_lookup __P((struct vnode *));
static struct mount *ml_lookup __P((struct mount *, int, int));
WINDOW *
openbufcache()
{
return (subwin(stdscr, LINES-5-1, 0, 5, 0));
}
void
closebufcache(w)
WINDOW *w;
{
if (w == NULL)
return;
wclear(w);
wrefresh(w);
delwin(w);
ml_init(); /* Clear out mount list */
}
void
labelbufcache()
{
mvwprintw(wnd, 0, 0, "There are %d buffers using %d kBytes of memory.",
nbuf, bufbytes / 1024);
wclrtoeol(wnd);
wmove(wnd, 1, 0);
wclrtoeol(wnd);
mvwaddstr(wnd, 2, 0,
"File System Bufs used % kB in use % Bufsize kB % Util %");
wclrtoeol(wnd);
}
void
showbufcache()
{
int tbuf, i, lastrow;
long tvalid, tsize;
struct ml_entry *ml;
tbuf = tvalid = tsize = 0;
lastrow = 3; /* Leave room for header. */
for (i = lastrow, ml = LIST_FIRST(&mount_list); ml != NULL;
i++, ml = LIST_NEXT(ml, ml_entries)) {
/* Display in window if enough room. */
if (i < getmaxy(wnd) - 2) {
mvwprintw(wnd, i, 0, "%-20.20s", ml->ml_addr == NULL ?
"NULL" : ml->ml_mount.mnt_stat.f_mntonname);
wprintw(wnd,
" %6d %3d %8ld %3d %8ld %3d %3d",
ml->ml_count,
(100 * ml->ml_count) / nbuf,
ml->ml_valid / 1024,
(100 * ml->ml_valid) / bufbytes,
ml->ml_size / 1024,
(100 * ml->ml_size) / bufbytes,
(100 * ml->ml_valid) / ml->ml_size);
wclrtoeol(wnd);
lastrow = i;
}
/* Update statistics. */
tbuf += ml->ml_count;
tvalid += ml->ml_valid / 1024;
tsize += ml->ml_size / 1024;
}
wclrtobot(wnd);
mvwprintw(wnd, lastrow + 2, 0,
"%-20s %6d %3d %8d %3d %8d %3d %3d",
"Total:", tbuf, (100 * tbuf) / nbuf,
tvalid, (100 * tvalid * 1024) / bufbytes,
tsize, (100 * tsize * 1024) / bufbytes, (100 * tvalid) / tsize);
}
int
initbufcache()
{
if (namelist[X_NBUF].n_type == 0) {
if (kvm_nlist(kd, namelist)) {
nlisterr(namelist);
return(0);
}
if (namelist[X_NBUF].n_type == 0) {
error("namelist on %s failed", _PATH_UNIX);
return(0);
}
}
NREAD(X_NBUF, &nbuf, sizeof(nbuf));
NREAD(X_BUFPAGES, &bufpages, sizeof(bufpages));
bufbytes = bufpages * sysconf(_SC_PAGESIZE);
if ((buf = malloc(nbuf * sizeof(struct buf))) == NULL) {
error("malloc failed");
die(0);
}
NREAD(X_BUF, &bufaddr, sizeof(bufaddr));
return(1);
}
void
fetchbufcache()
{
int i, count;
struct buf *bp;
struct vnode *vn;
struct mount *mt;
struct ml_entry *ml;
/* Re-read bufqueues lists and buffer cache headers */
NREAD(X_BUFQUEUES, bufqueues, sizeof(bufqueues));
KREAD(bufaddr, buf, sizeof(struct buf) * nbuf);
/* Initialise vnode cache and mount list. */
vc_init();
ml_init();
for (i = 0; i < BQUEUES; i++) {
for (bp = bufqueues[i].tqh_first; bp != NULL;
bp = bp->b_freelist.tqe_next) {
if (bp != NULL) {
bp = (struct buf *)((u_long)bp + (u_long)buf -
(u_long)bufaddr);
if (bp->b_vp != NULL) {
vn = vc_lookup(bp->b_vp);
if (vn == NULL)
errx(1,
"vc_lookup returns NULL!\n");
if (vn->v_mount != NULL)
mt = ml_lookup(vn->v_mount,
bp->b_bufsize,
bp->b_bcount);
}
}
}
}
/* simple sort - there's not that many entries */
do {
if ((ml = LIST_FIRST(&mount_list)) == NULL ||
LIST_NEXT(ml, ml_entries) == NULL)
break;
count = 0;
for (ml = LIST_FIRST(&mount_list); ml != NULL;
ml = LIST_NEXT(ml, ml_entries)) {
if (LIST_NEXT(ml, ml_entries) == NULL)
break;
if (ml->ml_count < LIST_NEXT(ml, ml_entries)->ml_count) {
ml = LIST_NEXT(ml, ml_entries);
LIST_REMOVE(ml, ml_entries);
LIST_INSERT_HEAD(&mount_list, ml, ml_entries);
count++;
}
}
} while (count != 0);
}
static void
vc_init()
{
int i;
/* vc_addr == NULL for unused cache entry. */
for (i = 0; i < VCACHE_SIZE; i++)
vcache[i].vc_addr = NULL;
}
static void
ml_init()
{
struct ml_entry *ml;
/* Throw out the current mount list and start again. */
while ((ml = LIST_FIRST(&mount_list)) != NULL) {
LIST_REMOVE(ml, ml_entries);
free(ml);
}
}
static struct vnode *
vc_lookup(vaddr)
struct vnode *vaddr;
{
struct vnode *ret;
int i, oldest, match;
ret = NULL;
oldest = match = 0;
for (i = 0; i < VCACHE_SIZE || vcache[i].vc_addr == NULL; i++) {
vcache[i].vc_age++;
if (vcache[i].vc_addr == NULL)
break;
if (vcache[i].vc_age < vcache[oldest].vc_age)
oldest = i;
if (vcache[i].vc_addr == vaddr) {
vcache[i].vc_age = 0;
match = i;
ret = &vcache[i].vc_node;
}
}
/* Find an entry in the cache? */
if (ret != NULL)
return(ret);
/* Go past the end of the cache? */
if (i >= VCACHE_SIZE)
i = oldest;
/* Read in new vnode and reset age counter. */
KREAD(vaddr, &vcache[i].vc_node, sizeof(struct vnode));
vcache[i].vc_addr = vaddr;
vcache[i].vc_age = 0;
return(&vcache[i].vc_node);
}
static struct mount *
ml_lookup(maddr, size, valid)
struct mount *maddr;
int size, valid;
{
struct ml_entry *ml;
for (ml = LIST_FIRST(&mount_list); ml != NULL;
ml = LIST_NEXT(ml, ml_entries))
if (ml->ml_addr == maddr) {
ml->ml_count++;
ml->ml_size += size;
ml->ml_valid += valid;
if (ml->ml_addr == NULL)
return(NULL);
else
return(&ml->ml_mount);
}
if ((ml = malloc(sizeof(struct ml_entry))) == NULL) {
error("out of memory");
die(0);
}
LIST_INSERT_HEAD(&mount_list, ml, ml_entries);
ml->ml_count = 1;
ml->ml_size = size;
ml->ml_valid = valid;
ml->ml_addr = maddr;
if (maddr == NULL)
return(NULL);
KREAD(maddr, &ml->ml_mount, sizeof(struct mount));
return(&ml->ml_mount);
}