xref: /freebsd/usr.bin/systat/swap.c (revision 1130b656e5fe4c2d1ba299e024d1b40eaeebd380)
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/stat.h>
47 #include <sys/rlist.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 	{ "_swaplist" },/* list of free swap areas */
66 #define VM_SWAPLIST	0
67 	{ "_swdevt" },	/* list of swap devices and sizes */
68 #define VM_SWDEVT	1
69 	{ "_nswap" },	/* size of largest swap device */
70 #define VM_NSWAP	2
71 	{ "_nswdev" },	/* number of swap devices */
72 #define VM_NSWDEV	3
73 	{ "_dmmax" },	/* maximum size of a swap block */
74 #define VM_DMMAX	4
75 	0
76 };
77 
78 static int nswap, nswdev, dmmax;
79 static struct swdevt *sw;
80 static long *perdev, blocksize;
81 static int nfree, hlen;
82 static struct rlisthdr swaplist;
83 
84 #define	SVAR(var) __STRING(var)	/* to force expansion */
85 #define	KGET(idx, var) \
86 	KGET1(idx, &var, sizeof(var), SVAR(var), (0))
87 #define	KGET1(idx, p, s, msg, rv) \
88 	KGET2(syms[idx].n_value, p, s, msg, rv)
89 #define	KGET2(addr, p, s, msg, rv) \
90 	if (kvm_read(kd, addr, p, s) != s) { \
91 		error("cannot read %s: %s", msg, kvm_geterr(kd)); \
92 		return rv; \
93 	}
94 
95 WINDOW *
96 openswap()
97 {
98 	return (subwin(stdscr, LINES-5-1, 0, 5, 0));
99 }
100 
101 void
102 closeswap(w)
103 	WINDOW *w;
104 {
105 	if (w == NULL)
106 		return;
107 	wclear(w);
108 	wrefresh(w);
109 	delwin(w);
110 }
111 
112 /*
113  * The meat of all the swap stuff is stolen from pstat(8)'s
114  * swapmode(), which is based on a program called swapinfo written by
115  * Kevin Lahey <kml@rokkaku.atl.ga.us>.
116  */
117 
118 initswap()
119 {
120 	int i;
121 	char msgbuf[BUFSIZ];
122 	static int once = 0;
123 	u_long ptr;
124 
125 	if (once)
126 		return (1);
127 	if (kvm_nlist(kd, syms)) {
128 		strcpy(msgbuf, "systat: swap: cannot find");
129 		for (i = 0; syms[i].n_name != NULL; i++) {
130 			if (syms[i].n_value == 0) {
131 				strcat(msgbuf, " ");
132 				strcat(msgbuf, syms[i].n_name);
133 			}
134 		}
135 		error(msgbuf);
136 		return (0);
137 	}
138 	KGET(VM_NSWAP, nswap);
139 	KGET(VM_NSWDEV, nswdev);
140 	KGET(VM_DMMAX, dmmax);
141 	if ((sw = malloc(nswdev * sizeof(*sw))) == NULL ||
142 	    (perdev = malloc(nswdev * sizeof(*perdev))) == NULL)
143 		err(1, "malloc");
144 	KGET1(VM_SWDEVT, &ptr, sizeof ptr, "swdevt", (0));
145 	KGET2(ptr, sw, nswdev * sizeof(*sw), "*swdevt", (0));
146 	once = 1;
147 	return (1);
148 }
149 
150 void
151 fetchswap()
152 {
153 	struct rlist head;
154 	struct rlist *swapptr;
155 
156 	/* Count up swap space. */
157 	nfree = 0;
158 	memset(perdev, 0, nswdev * sizeof(*perdev));
159 	KGET1(VM_SWAPLIST, &swaplist, sizeof swaplist, "swaplist", /* none */);
160 	swapptr = swaplist.rlh_list;
161 	while (swapptr) {
162 		int	top, bottom, next_block;
163 
164 		KGET2((unsigned long)swapptr, &head,
165 		      sizeof(struct rlist), "swapptr", /* none */);
166 
167 		top = head.rl_end;
168 		bottom = head.rl_start;
169 
170 		nfree += top - bottom + 1;
171 
172 		/*
173 		 * Swap space is split up among the configured disks.
174 		 *
175 		 * For interleaved swap devices, the first dmmax blocks
176 		 * of swap space some from the first disk, the next dmmax
177 		 * blocks from the next, and so on up to nswap blocks.
178 		 *
179 		 * The list of free space joins adjacent free blocks,
180 		 * ignoring device boundries.  If we want to keep track
181 		 * of this information per device, we'll just have to
182 		 * extract it ourselves.
183 		 */
184 		while (top / dmmax != bottom / dmmax) {
185 			next_block = ((bottom + dmmax) / dmmax);
186 			perdev[(bottom / dmmax) % nswdev] +=
187 				next_block * dmmax - bottom;
188 			bottom = next_block * dmmax;
189 		}
190 		perdev[(bottom / dmmax) % nswdev] +=
191 			top - bottom + 1;
192 
193 		swapptr = head.rl_next;
194 	}
195 
196 }
197 
198 void
199 labelswap()
200 {
201 	char *header;
202 	int row, i;
203 
204 	row = 0;
205 	wmove(wnd, row, 0); wclrtobot(wnd);
206 	header = getbsize(&hlen, &blocksize);
207 	mvwprintw(wnd, row++, 0, "%-5s%*s%9s %55s",
208 	    "Disk", hlen, header, "Used",
209 	    "/0%  /10% /20% /30% /40% /50% /60% /70% /80% /90% /100");
210 	for (i = 0; i < nswdev; i++) {
211 		if (!sw[i].sw_freed)
212 			continue;
213 		mvwprintw(wnd, i + 1, 0, "%-5s",
214 			  sw[i].sw_dev != NODEV?
215 			  devname(sw[i].sw_dev, S_IFBLK): "[NFS]");
216 	}
217 }
218 
219 void
220 showswap()
221 {
222 	int col, row, div, i, j, k, avail, npfree, used, xsize, xfree;
223 
224 	div = blocksize / 512;
225 	avail = npfree = 0;
226 	for (i = k = 0; i < nswdev; i++) {
227 		/*
228 		 * Don't report statistics for partitions which have not
229 		 * yet been activated via swapon(8).
230 		 */
231 		if (!sw[i].sw_freed)
232 			continue;
233 
234 		col = 5;
235 		mvwprintw(wnd, i + 1, col, "%*d", hlen, sw[i].sw_nblks / div);
236 		col += hlen;
237 
238 		/*
239 		 * The first dmmax is never allocated to avoid trashing of
240 		 * disklabels
241 		 */
242 		xsize = sw[i].sw_nblks - dmmax;
243 		xfree = perdev[i];
244 		used = xsize - xfree;
245 		mvwprintw(wnd, i + 1, col, "%9d  ", used / div);
246 		for (j = (100 * used / xsize + 1) / 2; j > 0; j--)
247 			waddch(wnd, 'X');
248 		npfree++;
249 		avail += xsize;
250 		k++;
251 	}
252 	/*
253 	 * If only one partition has been set up via swapon(8), we don't
254 	 * need to bother with totals.
255 	 */
256 	if (npfree > 1) {
257 		used = avail - nfree;
258 		mvwprintw(wnd, k + 1, 0, "%-5s%*d%9d  ",
259 		    "Total", hlen, avail / div, used / div);
260 		for (j = (100 * used / avail + 1) / 2; j > 0; j--)
261 			waddch(wnd, 'X');
262 	}
263 }
264