xref: /freebsd/usr.bin/systat/swap.c (revision a8445737e740901f5f2c8d24c12ef7fc8b00134e)
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
36 static char sccsid[] = "@(#)swap.c	8.3 (Berkeley) 4/29/95";
37 #endif
38 static const char rcsid[] =
39 	"$Id: swap.c,v 1.5 1997/07/06 04:37:22 bde Exp $";
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 
62 extern char *getbsize __P((int *headerlenp, long *blocksizep));
63 void showspace __P((char *header, int hlen, long blocksize));
64 
65 kvm_t	*kd;
66 
67 struct 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 
81 static int nswap, nswdev, dmmax;
82 static struct swdevt *sw;
83 static long *perdev, blocksize;
84 static int nfree, hlen;
85 static 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 
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 /*
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 
121 initswap()
122 {
123 	int i;
124 	char msgbuf[BUFSIZ];
125 	char *cp;
126 	static int once = 0;
127 	u_long ptr;
128 
129 	if (once)
130 		return (1);
131 	if (kvm_nlist(kd, syms)) {
132 		snprintf(msgbuf, sizeof(msgbuf), "systat: swap: cannot find");
133 		cp = msgbuf + strlen(msgbuf) + 1;
134 		for (i = 0;
135 		    syms[i].n_name != NULL && cp - msgbuf < sizeof(msgbuf);
136 		    i++) {
137 			if (syms[i].n_value == 0) {
138 				snprintf(cp, sizeof(msgbuf) - (cp - msgbuf),
139 				    " %s", syms[i].n_name);
140 				cp += strlen(cp) + 1;
141 			}
142 		}
143 		error(msgbuf);
144 		return (0);
145 	}
146 	KGET(VM_NSWAP, nswap);
147 	KGET(VM_NSWDEV, nswdev);
148 	KGET(VM_DMMAX, dmmax);
149 	if ((sw = malloc(nswdev * sizeof(*sw))) == NULL ||
150 	    (perdev = malloc(nswdev * sizeof(*perdev))) == NULL)
151 		err(1, "malloc");
152 	KGET1(VM_SWDEVT, &ptr, sizeof ptr, "swdevt", (0));
153 	KGET2(ptr, sw, nswdev * sizeof(*sw), "*swdevt", (0));
154 	once = 1;
155 	return (1);
156 }
157 
158 void
159 fetchswap()
160 {
161 	struct rlist head;
162 	struct rlist *swapptr;
163 
164 	/* Count up swap space. */
165 	nfree = 0;
166 	memset(perdev, 0, nswdev * sizeof(*perdev));
167 	KGET1(VM_SWAPLIST, &swaplist, sizeof swaplist, "swaplist", /* none */);
168 	swapptr = swaplist.rlh_list;
169 	while (swapptr) {
170 		int	top, bottom, next_block;
171 
172 		KGET2((unsigned long)swapptr, &head,
173 		      sizeof(struct rlist), "swapptr", /* none */);
174 
175 		top = head.rl_end;
176 		bottom = head.rl_start;
177 
178 		nfree += top - bottom + 1;
179 
180 		/*
181 		 * Swap space is split up among the configured disks.
182 		 *
183 		 * For interleaved swap devices, the first dmmax blocks
184 		 * of swap space some from the first disk, the next dmmax
185 		 * blocks from the next, and so on up to nswap blocks.
186 		 *
187 		 * The list of free space joins adjacent free blocks,
188 		 * ignoring device boundries.  If we want to keep track
189 		 * of this information per device, we'll just have to
190 		 * extract it ourselves.
191 		 */
192 		while (top / dmmax != bottom / dmmax) {
193 			next_block = ((bottom + dmmax) / dmmax);
194 			perdev[(bottom / dmmax) % nswdev] +=
195 				next_block * dmmax - bottom;
196 			bottom = next_block * dmmax;
197 		}
198 		perdev[(bottom / dmmax) % nswdev] +=
199 			top - bottom + 1;
200 
201 		swapptr = head.rl_next;
202 	}
203 
204 }
205 
206 void
207 labelswap()
208 {
209 	char *header, *p;
210 	int row, i;
211 
212 	row = 0;
213 	wmove(wnd, row, 0); wclrtobot(wnd);
214 	header = getbsize(&hlen, &blocksize);
215 	mvwprintw(wnd, row++, 0, "%-5s%*s%9s %55s",
216 	    "Disk", hlen, header, "Used",
217 	    "/0%  /10% /20% /30% /40% /50% /60% /70% /80% /90% /100");
218 	for (i = 0; i < nswdev; i++) {
219 		if (!sw[i].sw_freed)
220 			continue;
221 		p = devname(sw[i].sw_dev, S_IFBLK);
222 		mvwprintw(wnd, i + 1, 0, "%-5s",
223 			  sw[i].sw_dev == NODEV ? "[NFS]" :
224 			  p == NULL ? "??" : p);
225 	}
226 }
227 
228 void
229 showswap()
230 {
231 	int col, row, div, i, j, k, avail, npfree, used, xsize, xfree;
232 
233 	div = blocksize / 512;
234 	avail = npfree = 0;
235 	for (i = k = 0; i < nswdev; i++) {
236 		/*
237 		 * Don't report statistics for partitions which have not
238 		 * yet been activated via swapon(8).
239 		 */
240 		if (!sw[i].sw_freed)
241 			continue;
242 
243 		col = 5;
244 		mvwprintw(wnd, i + 1, col, "%*d", hlen, sw[i].sw_nblks / div);
245 		col += hlen;
246 
247 		/*
248 		 * The first dmmax is never allocated to avoid trashing of
249 		 * disklabels
250 		 */
251 		xsize = sw[i].sw_nblks - dmmax;
252 		xfree = perdev[i];
253 		used = xsize - xfree;
254 		mvwprintw(wnd, i + 1, col, "%9d  ", used / div);
255 		for (j = (100 * used / xsize + 1) / 2; j > 0; j--)
256 			waddch(wnd, 'X');
257 		npfree++;
258 		avail += xsize;
259 		k++;
260 	}
261 	/*
262 	 * If only one partition has been set up via swapon(8), we don't
263 	 * need to bother with totals.
264 	 */
265 	if (npfree > 1) {
266 		used = avail - nfree;
267 		mvwprintw(wnd, k + 1, 0, "%-5s%*d%9d  ",
268 		    "Total", hlen, avail / div, used / div);
269 		for (j = (100 * used / avail + 1) / 2; j > 0; j--)
270 			waddch(wnd, 'X');
271 	}
272 }
273