swap.c revision 27232 
1/*-
2 * Copyright (c) 1980, 1992, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35#if 0
36static char sccsid[] = "@(#)swap.c	8.3 (Berkeley) 4/29/95";
37#endif
38static const char rcsid[] =
39	"$Id$";
40#endif /* not lint */
41
42/*
43 * swapinfo - based on a program of the same name by Kevin Lahey
44 */
45
46#include <sys/param.h>
47#include <sys/buf.h>
48#include <sys/conf.h>
49#include <sys/ioctl.h>
50#include <sys/stat.h>
51#include <sys/rlist.h>
52
53#include <kvm.h>
54#include <nlist.h>
55#include <stdio.h>
56#include <stdlib.h>
57#include <unistd.h>
58
59#include "systat.h"
60#include "extern.h"
61
62extern char *getbsize __P((int *headerlenp, long *blocksizep));
63void showspace __P((char *header, int hlen, long blocksize));
64
65kvm_t	*kd;
66
67struct nlist syms[] = {
68	{ "_swaplist" },/* list of free swap areas */
69#define VM_SWAPLIST	0
70	{ "_swdevt" },	/* list of swap devices and sizes */
71#define VM_SWDEVT	1
72	{ "_nswap" },	/* size of largest swap device */
73#define VM_NSWAP	2
74	{ "_nswdev" },	/* number of swap devices */
75#define VM_NSWDEV	3
76	{ "_dmmax" },	/* maximum size of a swap block */
77#define VM_DMMAX	4
78	0
79};
80
81static int nswap, nswdev, dmmax;
82static struct swdevt *sw;
83static long *perdev, blocksize;
84static int nfree, hlen;
85static struct rlisthdr swaplist;
86
87#define	SVAR(var) __STRING(var)	/* to force expansion */
88#define	KGET(idx, var) \
89	KGET1(idx, &var, sizeof(var), SVAR(var), (0))
90#define	KGET1(idx, p, s, msg, rv) \
91	KGET2(syms[idx].n_value, p, s, msg, rv)
92#define	KGET2(addr, p, s, msg, rv) \
93	if (kvm_read(kd, addr, p, s) != s) { \
94		error("cannot read %s: %s", msg, kvm_geterr(kd)); \
95		return rv; \
96	}
97
98WINDOW *
99openswap()
100{
101	return (subwin(stdscr, LINES-5-1, 0, 5, 0));
102}
103
104void
105closeswap(w)
106	WINDOW *w;
107{
108	if (w == NULL)
109		return;
110	wclear(w);
111	wrefresh(w);
112	delwin(w);
113}
114
115/*
116 * The meat of all the swap stuff is stolen from pstat(8)'s
117 * swapmode(), which is based on a program called swapinfo written by
118 * Kevin Lahey <kml@rokkaku.atl.ga.us>.
119 */
120
121initswap()
122{
123	int i;
124	char msgbuf[BUFSIZ];
125	static int once = 0;
126	u_long ptr;
127
128	if (once)
129		return (1);
130	if (kvm_nlist(kd, syms)) {
131		strcpy(msgbuf, "systat: swap: cannot find");
132		for (i = 0; syms[i].n_name != NULL; i++) {
133			if (syms[i].n_value == 0) {
134				strcat(msgbuf, " ");
135				strcat(msgbuf, syms[i].n_name);
136			}
137		}
138		error(msgbuf);
139		return (0);
140	}
141	KGET(VM_NSWAP, nswap);
142	KGET(VM_NSWDEV, nswdev);
143	KGET(VM_DMMAX, dmmax);
144	if ((sw = malloc(nswdev * sizeof(*sw))) == NULL ||
145	    (perdev = malloc(nswdev * sizeof(*perdev))) == NULL)
146		err(1, "malloc");
147	KGET1(VM_SWDEVT, &ptr, sizeof ptr, "swdevt", (0));
148	KGET2(ptr, sw, nswdev * sizeof(*sw), "*swdevt", (0));
149	once = 1;
150	return (1);
151}
152
153void
154fetchswap()
155{
156	struct rlist head;
157	struct rlist *swapptr;
158
159	/* Count up swap space. */
160	nfree = 0;
161	memset(perdev, 0, nswdev * sizeof(*perdev));
162	KGET1(VM_SWAPLIST, &swaplist, sizeof swaplist, "swaplist", /* none */);
163	swapptr = swaplist.rlh_list;
164	while (swapptr) {
165		int	top, bottom, next_block;
166
167		KGET2((unsigned long)swapptr, &head,
168		      sizeof(struct rlist), "swapptr", /* none */);
169
170		top = head.rl_end;
171		bottom = head.rl_start;
172
173		nfree += top - bottom + 1;
174
175		/*
176		 * Swap space is split up among the configured disks.
177		 *
178		 * For interleaved swap devices, the first dmmax blocks
179		 * of swap space some from the first disk, the next dmmax
180		 * blocks from the next, and so on up to nswap blocks.
181		 *
182		 * The list of free space joins adjacent free blocks,
183		 * ignoring device boundries.  If we want to keep track
184		 * of this information per device, we'll just have to
185		 * extract it ourselves.
186		 */
187		while (top / dmmax != bottom / dmmax) {
188			next_block = ((bottom + dmmax) / dmmax);
189			perdev[(bottom / dmmax) % nswdev] +=
190				next_block * dmmax - bottom;
191			bottom = next_block * dmmax;
192		}
193		perdev[(bottom / dmmax) % nswdev] +=
194			top - bottom + 1;
195
196		swapptr = head.rl_next;
197	}
198
199}
200
201void
202labelswap()
203{
204	char *header, *p;
205	int row, i;
206
207	row = 0;
208	wmove(wnd, row, 0); wclrtobot(wnd);
209	header = getbsize(&hlen, &blocksize);
210	mvwprintw(wnd, row++, 0, "%-5s%*s%9s %55s",
211	    "Disk", hlen, header, "Used",
212	    "/0%  /10% /20% /30% /40% /50% /60% /70% /80% /90% /100");
213	for (i = 0; i < nswdev; i++) {
214		if (!sw[i].sw_freed)
215			continue;
216		p = devname(sw[i].sw_dev, S_IFBLK);
217		mvwprintw(wnd, i + 1, 0, "%-5s",
218			  sw[i].sw_dev == NODEV ? "[NFS]" :
219			  p == NULL ? "??" : p);
220	}
221}
222
223void
224showswap()
225{
226	int col, row, div, i, j, k, avail, npfree, used, xsize, xfree;
227
228	div = blocksize / 512;
229	avail = npfree = 0;
230	for (i = k = 0; i < nswdev; i++) {
231		/*
232		 * Don't report statistics for partitions which have not
233		 * yet been activated via swapon(8).
234		 */
235		if (!sw[i].sw_freed)
236			continue;
237
238		col = 5;
239		mvwprintw(wnd, i + 1, col, "%*d", hlen, sw[i].sw_nblks / div);
240		col += hlen;
241
242		/*
243		 * The first dmmax is never allocated to avoid trashing of
244		 * disklabels
245		 */
246		xsize = sw[i].sw_nblks - dmmax;
247		xfree = perdev[i];
248		used = xsize - xfree;
249		mvwprintw(wnd, i + 1, col, "%9d  ", used / div);
250		for (j = (100 * used / xsize + 1) / 2; j > 0; j--)
251			waddch(wnd, 'X');
252		npfree++;
253		avail += xsize;
254		k++;
255	}
256	/*
257	 * If only one partition has been set up via swapon(8), we don't
258	 * need to bother with totals.
259	 */
260	if (npfree > 1) {
261		used = avail - nfree;
262		mvwprintw(wnd, k + 1, 0, "%-5s%*d%9d  ",
263		    "Total", hlen, avail / div, used / div);
264		for (j = (100 * used / avail + 1) / 2; j > 0; j--)
265			waddch(wnd, 'X');
266	}
267}
268