xref: /freebsd/usr.bin/systat/swap.c (revision afe61c15161c324a7af299a9b8457aba5afc92db)
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 static char sccsid[] = "@(#)swap.c	8.2 (Berkeley) 2/21/94";
36 #endif /* not lint */
37 
38 /*
39  * swapinfo - based on a program of the same name by Kevin Lahey
40  */
41 
42 #include <sys/param.h>
43 #include <sys/buf.h>
44 #include <sys/conf.h>
45 #include <sys/ioctl.h>
46 #include <sys/map.h>
47 #include <sys/stat.h>
48 
49 #include <kvm.h>
50 #include <nlist.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <unistd.h>
54 
55 #include "systat.h"
56 #include "extern.h"
57 
58 extern char *devname __P((int, int));
59 extern char *getbsize __P((int *headerlenp, long *blocksizep));
60 void showspace __P((char *header, int hlen, long blocksize));
61 
62 kvm_t	*kd;
63 
64 struct nlist syms[] = {
65 	{ "_swapmap" },	/* list of free swap areas */
66 #define VM_SWAPMAP	0
67 	{ "_nswapmap" },/* size of the swap map */
68 #define VM_NSWAPMAP	1
69 	{ "_swdevt" },	/* list of swap devices and sizes */
70 #define VM_SWDEVT	2
71 	{ "_nswap" },	/* size of largest swap device */
72 #define VM_NSWAP	3
73 	{ "_nswdev" },	/* number of swap devices */
74 #define VM_NSWDEV	4
75 	{ "_dmmax" },	/* maximum size of a swap block */
76 #define VM_DMMAX	5
77 	0
78 };
79 
80 static int nswap, nswdev, dmmax, nswapmap;
81 static struct swdevt *sw;
82 static long *perdev, blocksize;
83 static struct map *swapmap, *kswapmap;
84 static struct mapent *mp;
85 static int nfree, hlen;
86 
87 #define	SVAR(var) __STRING(var)	/* to force expansion */
88 #define	KGET(idx, var) \
89 	KGET1(idx, &var, sizeof(var), SVAR(var))
90 #define	KGET1(idx, p, s, msg) \
91 	KGET2(syms[idx].n_value, p, s, msg)
92 #define	KGET2(addr, p, s, msg) \
93 	if (kvm_read(kd, addr, p, s) != s) { \
94 		error("cannot read %s: %s", msg, kvm_geterr(kd)); \
95 		return (0); \
96 	}
97 
98 WINDOW *
99 openswap()
100 {
101 	return (subwin(stdscr, LINES-5-1, 0, 5, 0));
102 }
103 
104 void
105 closeswap(w)
106 	WINDOW *w;
107 {
108 	if (w == NULL)
109 		return;
110 	wclear(w);
111 	wrefresh(w);
112 	delwin(w);
113 }
114 
115 initswap()
116 {
117 	int i;
118 	char msgbuf[BUFSIZ];
119 	static int once = 0;
120 
121 	if (once)
122 		return (1);
123 	if (kvm_nlist(kd, syms)) {
124 		strcpy(msgbuf, "systat: swap: cannot find");
125 		for (i = 0; syms[i].n_name != NULL; i++) {
126 			if (syms[i].n_value == 0) {
127 				strcat(msgbuf, " ");
128 				strcat(msgbuf, syms[i].n_name);
129 			}
130 		}
131 		error(msgbuf);
132 		return (0);
133 	}
134 	KGET(VM_NSWAP, nswap);
135 	KGET(VM_NSWDEV, nswdev);
136 	KGET(VM_DMMAX, dmmax);
137 	KGET(VM_NSWAPMAP, nswapmap);
138 	KGET(VM_SWAPMAP, kswapmap);	/* kernel `swapmap' is a pointer */
139 	if ((sw = malloc(nswdev * sizeof(*sw))) == NULL ||
140 	    (perdev = malloc(nswdev * sizeof(*perdev))) == NULL ||
141 	    (mp = malloc(nswapmap * sizeof(*mp))) == NULL) {
142 		error("swap malloc");
143 		return (0);
144 	}
145 	KGET1(VM_SWDEVT, sw, nswdev * sizeof(*sw), "swdevt");
146 	once = 1;
147 	return (1);
148 }
149 
150 void
151 fetchswap()
152 {
153 	int s, e, i;
154 
155 	s = nswapmap * sizeof(*mp);
156 	if (kvm_read(kd, (long)kswapmap, mp, s) != s)
157 		error("cannot read swapmap: %s", kvm_geterr(kd));
158 
159 	/* first entry in map is `struct map'; rest are mapent's */
160 	swapmap = (struct map *)mp;
161 	if (nswapmap != swapmap->m_limit - (struct mapent *)kswapmap)
162 		error("panic: swap: nswapmap goof");
163 
164 	/*
165 	 * Count up swap space.
166 	 */
167 	nfree = 0;
168 	bzero(perdev, nswdev * sizeof(*perdev));
169 	for (mp++; mp->m_addr != 0; mp++) {
170 		s = mp->m_addr;			/* start of swap region */
171 		e = mp->m_addr + mp->m_size;	/* end of region */
172 		nfree += mp->m_size;
173 
174 		/*
175 		 * Swap space is split up among the configured disks.
176 		 * The first dmmax blocks of swap space some from the
177 		 * first disk, the next dmmax blocks from the next,
178 		 * and so on.  The list of free space joins adjacent
179 		 * free blocks, ignoring device boundries.  If we want
180 		 * to keep track of this information per device, we'll
181 		 * just have to extract it ourselves.
182 		 */
183 
184 		/* calculate first device on which this falls */
185 		i = (s / dmmax) % nswdev;
186 		while (s < e) {		/* XXX this is inefficient */
187 			int bound = roundup(s + 1, dmmax);
188 
189 			if (bound > e)
190 				bound = e;
191 			perdev[i] += bound - s;
192 			if (++i >= nswdev)
193 				i = 0;
194 			s = bound;
195 		}
196 	}
197 }
198 
199 void
200 labelswap()
201 {
202 	char *header;
203 	int row, i;
204 
205 	row = 0;
206 	wmove(wnd, row, 0); wclrtobot(wnd);
207 	header = getbsize(&hlen, &blocksize);
208 	mvwprintw(wnd, row++, 0, "%-5s%*s%9s  %55s",
209 	    "Disk", hlen, header, "Used",
210 	    "/0%  /10% /20% /30% /40% /50% /60% /70% /80% /90% /100%");
211 	for (i = 0; i < nswdev; i++) {
212 		mvwprintw(wnd, i + 1, 0, "%-5s",
213 		    devname(sw[i].sw_dev, S_IFBLK));
214 	}
215 }
216 
217 void
218 showswap()
219 {
220 	int col, row, div, i, j, avail, npfree, used, xsize, xfree;
221 
222 	div = blocksize / 512;
223 	avail = npfree = 0;
224 	for (i = 0; i < nswdev; i++) {
225 		col = 5;
226 		mvwprintw(wnd, i + 1, col, "%*d", hlen, sw[i].sw_nblks / div);
227 		col += hlen;
228 		/*
229 		 * Don't report statistics for partitions which have not
230 		 * yet been activated via swapon(8).
231 		 */
232 		if (!sw[i].sw_freed) {
233 			mvwprintw(wnd, i + 1, col + 8,
234 			    "0  *** not available for swapping ***");
235 			continue;
236 		}
237 		xsize = sw[i].sw_nblks;
238 		xfree = perdev[i];
239 		used = xsize - xfree;
240 		mvwprintw(wnd, i + 1, col, "%9d  ", used / div);
241 		for (j = (100 * used / xsize + 1) / 2; j > 0; j--)
242 			waddch(wnd, 'X');
243 		npfree++;
244 		avail += xsize;
245 	}
246 	/*
247 	 * If only one partition has been set up via swapon(8), we don't
248 	 * need to bother with totals.
249 	 */
250 	if (npfree > 1) {
251 		used = avail - nfree;
252 		mvwprintw(wnd, i + 1, 0, "%-5s%*d%9d  ",
253 		    "Total", hlen, avail / div, used / div);
254 		for (j = (100 * used / avail + 1) / 2; j > 0; j--)
255 			waddch(wnd, 'X');
256 	}
257 }
258