gmon.c revision 1.14 1 /* $NetBSD: gmon.c,v 1.14 1998/11/13 15:47:09 christos Exp $ */
2
3 /*-
4 * Copyright (c) 1983, 1992, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by the University of
18 * California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #include <sys/cdefs.h>
37 #if !defined(lint) && defined(LIBC_SCCS)
38 #if 0
39 static char sccsid[] = "@(#)gmon.c 8.1 (Berkeley) 6/4/93";
40 #else
41 __RCSID("$NetBSD: gmon.c,v 1.14 1998/11/13 15:47:09 christos Exp $");
42 #endif
43 #endif
44
45 #include "namespace.h"
46 #include <sys/param.h>
47 #include <sys/time.h>
48 #include <sys/gmon.h>
49 #include <sys/sysctl.h>
50
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <fcntl.h>
54 #include <limits.h>
55 #include <unistd.h>
56 #include <err.h>
57
58 extern char *minbrk __asm ("minbrk");
59
60 struct gmonparam _gmonparam = { GMON_PROF_OFF };
61
62 static u_int s_scale;
63 /* see profil(2) where this is describe (incorrectly) */
64 #define SCALE_1_TO_1 0x10000L
65
66 #define ERR(s) write(STDERR_FILENO, s, sizeof(s))
67
68 void moncontrol __P((int));
69 void monstartup __P((u_long, u_long));
70 void _mcleanup __P((void));
71 static int hertz __P((void));
72
73 void
74 monstartup(lowpc, highpc)
75 u_long lowpc;
76 u_long highpc;
77 {
78 long o;
79 char *cp;
80 struct gmonparam *p = &_gmonparam;
81
82 /*
83 * round lowpc and highpc to multiples of the density we're using
84 * so the rest of the scaling (here and in gprof) stays in ints.
85 */
86 p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER));
87 p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER));
88 p->textsize = p->highpc - p->lowpc;
89 p->kcountsize = p->textsize / HISTFRACTION;
90 p->hashfraction = HASHFRACTION;
91 p->fromssize = p->textsize / p->hashfraction;
92 p->tolimit = p->textsize * ARCDENSITY / 100;
93 if (p->tolimit < MINARCS)
94 p->tolimit = MINARCS;
95 else if (p->tolimit > MAXARCS)
96 p->tolimit = MAXARCS;
97 p->tossize = p->tolimit * sizeof(struct tostruct);
98
99 cp = sbrk((int)(p->kcountsize + p->fromssize + p->tossize));
100 if (cp == (char *)-1) {
101 ERR("monstartup: out of memory\n");
102 return;
103 }
104 #ifdef notdef
105 memset(cp, 0, p->kcountsize + p->fromssize + p->tossize);
106 #endif
107 p->tos = (struct tostruct *)(void *)cp;
108 cp += (size_t)p->tossize;
109 p->kcount = (u_short *)(void *)cp;
110 cp += (size_t)p->kcountsize;
111 p->froms = (u_short *)(void *)cp;
112
113 minbrk = sbrk(0);
114 p->tos[0].link = 0;
115
116 o = p->highpc - p->lowpc;
117 if (p->kcountsize < o) {
118 #ifndef notdef
119 s_scale = ((float)p->kcountsize / o ) * SCALE_1_TO_1;
120 #else /* avoid floating point */
121 int quot = o / p->kcountsize;
122
123 if (quot >= 0x10000)
124 s_scale = 1;
125 else if (quot >= 0x100)
126 s_scale = 0x10000 / quot;
127 else if (o >= 0x800000)
128 s_scale = 0x1000000 / (o / (p->kcountsize >> 8));
129 else
130 s_scale = 0x1000000 / ((o << 8) / p->kcountsize);
131 #endif
132 } else
133 s_scale = SCALE_1_TO_1;
134
135 moncontrol(1);
136 }
137
138 void
139 _mcleanup()
140 {
141 int fd;
142 int fromindex;
143 int endfrom;
144 u_long frompc;
145 int toindex;
146 struct rawarc rawarc;
147 struct gmonparam *p = &_gmonparam;
148 struct gmonhdr gmonhdr, *hdr;
149 struct clockinfo clockinfo;
150 int mib[2];
151 size_t size;
152 char *profdir;
153 char *proffile;
154 char buf[PATH_MAX];
155 int len = sizeof(buf) - 1;
156 #ifdef DEBUG
157 int log, len;
158 char buf2[200];
159 #endif
160
161 if (p->state == GMON_PROF_ERROR)
162 ERR("_mcleanup: tos overflow\n");
163
164 size = sizeof(clockinfo);
165 mib[0] = CTL_KERN;
166 mib[1] = KERN_CLOCKRATE;
167 if (sysctl(mib, 2, &clockinfo, &size, NULL, 0) < 0) {
168 /*
169 * Best guess
170 */
171 clockinfo.profhz = hertz();
172 } else if (clockinfo.profhz == 0) {
173 if (clockinfo.hz != 0)
174 clockinfo.profhz = clockinfo.hz;
175 else
176 clockinfo.profhz = hertz();
177 }
178
179 moncontrol(0);
180
181 if ((profdir = getenv("PROFDIR")) != NULL) {
182 extern char *__progname;
183 char *s, *t;
184 pid_t pid;
185 long divisor;
186
187 /* If PROFDIR contains a null value, no profiling
188 output is produced */
189 if (*profdir == '\0') {
190 return;
191 }
192
193 t = buf;
194 s = profdir;
195 while ((*t = *s) != '\0') {
196 if (len-- == 0) {
197 warnx("_mcleanup: internal buffer overflow, PROFDIR too long");
198 return;
199 }
200 t++;
201 s++;
202 }
203 *t++ = '/';
204
205 /*
206 * Copy and convert pid from a pid_t to a string. For
207 * best performance, divisor should be initialized to
208 * the largest power of 10 less than PID_MAX.
209 */
210 pid = getpid();
211 divisor=10000;
212 while (divisor > pid) divisor /= 10; /* skip leading zeros */
213 do {
214 *t++ = (char)((pid/divisor) + '0');
215 pid %= (pid_t)divisor;
216 } while (divisor /= 10);
217 *t++ = '.';
218
219 s = __progname;
220 while ((*t++ = *s++) != '\0')
221 ;
222
223 proffile = buf;
224 } else {
225 proffile = "gmon.out";
226 }
227
228 fd = open(proffile , O_CREAT|O_TRUNC|O_WRONLY, 0666);
229 if (fd < 0) {
230 warn("mcount: Cannot open `%s'", proffile);
231 return;
232 }
233 #ifdef DEBUG
234 log = open("gmon.log", O_CREAT|O_TRUNC|O_WRONLY, 0664);
235 if (log < 0) {
236 warn("mcount: Cannot open `gmon.log'");
237 return;
238 }
239 len = snprintf(buf2, sizeof buf2, "[mcleanup1] kcount 0x%x ssiz %d\n",
240 p->kcount, p->kcountsize);
241 write(log, buf2, len);
242 #endif
243 hdr = (struct gmonhdr *)&gmonhdr;
244 hdr->lpc = p->lowpc;
245 hdr->hpc = p->highpc;
246 hdr->ncnt = (int)(p->kcountsize + sizeof(gmonhdr));
247 hdr->version = GMONVERSION;
248 hdr->profrate = clockinfo.profhz;
249 (void)write(fd, hdr, sizeof *hdr);
250 (void)write(fd, p->kcount, (size_t)p->kcountsize);
251 endfrom = (int)(p->fromssize / sizeof(*p->froms));
252 for (fromindex = 0; fromindex < endfrom; fromindex++) {
253 if (p->froms[fromindex] == 0)
254 continue;
255
256 frompc = p->lowpc;
257 frompc += fromindex * p->hashfraction * sizeof(*p->froms);
258 for (toindex = p->froms[fromindex]; toindex != 0;
259 toindex = p->tos[toindex].link) {
260 #ifdef DEBUG
261 len = snprintf(buf2, sizeof buf2,
262 "[mcleanup2] frompc 0x%x selfpc 0x%x count %d\n" ,
263 frompc, p->tos[toindex].selfpc,
264 p->tos[toindex].count);
265 write(log, buf2, len);
266 #endif
267 rawarc.raw_frompc = frompc;
268 rawarc.raw_selfpc = p->tos[toindex].selfpc;
269 rawarc.raw_count = p->tos[toindex].count;
270 write(fd, &rawarc, sizeof rawarc);
271 }
272 }
273 close(fd);
274 }
275
276 /*
277 * Control profiling
278 * profiling is what mcount checks to see if
279 * all the data structures are ready.
280 */
281 void
282 moncontrol(mode)
283 int mode;
284 {
285 struct gmonparam *p = &_gmonparam;
286
287 if (mode) {
288 /* start */
289 profil((char *)(void *)p->kcount, (size_t)p->kcountsize,
290 p->lowpc, s_scale);
291 p->state = GMON_PROF_ON;
292 } else {
293 /* stop */
294 profil(NULL, 0, (u_long)0, 0);
295 p->state = GMON_PROF_OFF;
296 }
297 }
298
299 /*
300 * discover the tick frequency of the machine
301 * if something goes wrong, we return 0, an impossible hertz.
302 */
303 static int
304 hertz()
305 {
306 struct itimerval tim;
307
308 tim.it_interval.tv_sec = 0;
309 tim.it_interval.tv_usec = 1;
310 tim.it_value.tv_sec = 0;
311 tim.it_value.tv_usec = 0;
312 setitimer(ITIMER_REAL, &tim, 0);
313 setitimer(ITIMER_REAL, 0, &tim);
314 if (tim.it_interval.tv_usec < 2)
315 return(0);
316 return (int)(1000000 / tim.it_interval.tv_usec);
317 }
318