gmon.c revision 1.15 1 /* $NetBSD: gmon.c,v 1.15 1999/01/14 22:48:19 kleink 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 1.15 1999/01/14 22:48:19 kleink 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 #include "extern.h"
58
59 struct gmonparam _gmonparam = { GMON_PROF_OFF };
60
61 static u_int s_scale;
62 /* see profil(2) where this is describe (incorrectly) */
63 #define SCALE_1_TO_1 0x10000L
64
65 #define ERR(s) write(STDERR_FILENO, s, sizeof(s))
66
67 void moncontrol __P((int));
68 void monstartup __P((u_long, u_long));
69 void _mcleanup __P((void));
70 static int hertz __P((void));
71
72 void
73 monstartup(lowpc, highpc)
74 u_long lowpc;
75 u_long highpc;
76 {
77 long o;
78 char *cp;
79 struct gmonparam *p = &_gmonparam;
80
81 /*
82 * round lowpc and highpc to multiples of the density we're using
83 * so the rest of the scaling (here and in gprof) stays in ints.
84 */
85 p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER));
86 p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER));
87 p->textsize = p->highpc - p->lowpc;
88 p->kcountsize = p->textsize / HISTFRACTION;
89 p->hashfraction = HASHFRACTION;
90 p->fromssize = p->textsize / p->hashfraction;
91 p->tolimit = p->textsize * ARCDENSITY / 100;
92 if (p->tolimit < MINARCS)
93 p->tolimit = MINARCS;
94 else if (p->tolimit > MAXARCS)
95 p->tolimit = MAXARCS;
96 p->tossize = p->tolimit * sizeof(struct tostruct);
97
98 cp = sbrk((int)(p->kcountsize + p->fromssize + p->tossize));
99 if (cp == (char *)-1) {
100 ERR("monstartup: out of memory\n");
101 return;
102 }
103 #ifdef notdef
104 memset(cp, 0, p->kcountsize + p->fromssize + p->tossize);
105 #endif
106 p->tos = (struct tostruct *)(void *)cp;
107 cp += (size_t)p->tossize;
108 p->kcount = (u_short *)(void *)cp;
109 cp += (size_t)p->kcountsize;
110 p->froms = (u_short *)(void *)cp;
111
112 __minbrk = sbrk(0);
113 p->tos[0].link = 0;
114
115 o = p->highpc - p->lowpc;
116 if (p->kcountsize < o) {
117 #ifndef notdef
118 s_scale = ((float)p->kcountsize / o ) * SCALE_1_TO_1;
119 #else /* avoid floating point */
120 int quot = o / p->kcountsize;
121
122 if (quot >= 0x10000)
123 s_scale = 1;
124 else if (quot >= 0x100)
125 s_scale = 0x10000 / quot;
126 else if (o >= 0x800000)
127 s_scale = 0x1000000 / (o / (p->kcountsize >> 8));
128 else
129 s_scale = 0x1000000 / ((o << 8) / p->kcountsize);
130 #endif
131 } else
132 s_scale = SCALE_1_TO_1;
133
134 moncontrol(1);
135 }
136
137 void
138 _mcleanup()
139 {
140 int fd;
141 int fromindex;
142 int endfrom;
143 u_long frompc;
144 int toindex;
145 struct rawarc rawarc;
146 struct gmonparam *p = &_gmonparam;
147 struct gmonhdr gmonhdr, *hdr;
148 struct clockinfo clockinfo;
149 int mib[2];
150 size_t size;
151 char *profdir;
152 char *proffile;
153 char buf[PATH_MAX];
154 int len = sizeof(buf) - 1;
155 #ifdef DEBUG
156 int log, len;
157 char buf2[200];
158 #endif
159
160 if (p->state == GMON_PROF_ERROR)
161 ERR("_mcleanup: tos overflow\n");
162
163 size = sizeof(clockinfo);
164 mib[0] = CTL_KERN;
165 mib[1] = KERN_CLOCKRATE;
166 if (sysctl(mib, 2, &clockinfo, &size, NULL, 0) < 0) {
167 /*
168 * Best guess
169 */
170 clockinfo.profhz = hertz();
171 } else if (clockinfo.profhz == 0) {
172 if (clockinfo.hz != 0)
173 clockinfo.profhz = clockinfo.hz;
174 else
175 clockinfo.profhz = hertz();
176 }
177
178 moncontrol(0);
179
180 if ((profdir = getenv("PROFDIR")) != NULL) {
181 extern char *__progname;
182 char *s, *t;
183 pid_t pid;
184 long divisor;
185
186 /* If PROFDIR contains a null value, no profiling
187 output is produced */
188 if (*profdir == '\0') {
189 return;
190 }
191
192 t = buf;
193 s = profdir;
194 while ((*t = *s) != '\0') {
195 if (len-- == 0) {
196 warnx("_mcleanup: internal buffer overflow, PROFDIR too long");
197 return;
198 }
199 t++;
200 s++;
201 }
202 *t++ = '/';
203
204 /*
205 * Copy and convert pid from a pid_t to a string. For
206 * best performance, divisor should be initialized to
207 * the largest power of 10 less than PID_MAX.
208 */
209 pid = getpid();
210 divisor=10000;
211 while (divisor > pid) divisor /= 10; /* skip leading zeros */
212 do {
213 *t++ = (char)((pid/divisor) + '0');
214 pid %= (pid_t)divisor;
215 } while (divisor /= 10);
216 *t++ = '.';
217
218 s = __progname;
219 while ((*t++ = *s++) != '\0')
220 ;
221
222 proffile = buf;
223 } else {
224 proffile = "gmon.out";
225 }
226
227 fd = open(proffile , O_CREAT|O_TRUNC|O_WRONLY, 0666);
228 if (fd < 0) {
229 warn("mcount: Cannot open `%s'", proffile);
230 return;
231 }
232 #ifdef DEBUG
233 log = open("gmon.log", O_CREAT|O_TRUNC|O_WRONLY, 0664);
234 if (log < 0) {
235 warn("mcount: Cannot open `gmon.log'");
236 return;
237 }
238 len = snprintf(buf2, sizeof buf2, "[mcleanup1] kcount 0x%x ssiz %d\n",
239 p->kcount, p->kcountsize);
240 write(log, buf2, len);
241 #endif
242 hdr = (struct gmonhdr *)&gmonhdr;
243 hdr->lpc = p->lowpc;
244 hdr->hpc = p->highpc;
245 hdr->ncnt = (int)(p->kcountsize + sizeof(gmonhdr));
246 hdr->version = GMONVERSION;
247 hdr->profrate = clockinfo.profhz;
248 (void)write(fd, hdr, sizeof *hdr);
249 (void)write(fd, p->kcount, (size_t)p->kcountsize);
250 endfrom = (int)(p->fromssize / sizeof(*p->froms));
251 for (fromindex = 0; fromindex < endfrom; fromindex++) {
252 if (p->froms[fromindex] == 0)
253 continue;
254
255 frompc = p->lowpc;
256 frompc += fromindex * p->hashfraction * sizeof(*p->froms);
257 for (toindex = p->froms[fromindex]; toindex != 0;
258 toindex = p->tos[toindex].link) {
259 #ifdef DEBUG
260 len = snprintf(buf2, sizeof buf2,
261 "[mcleanup2] frompc 0x%x selfpc 0x%x count %d\n" ,
262 frompc, p->tos[toindex].selfpc,
263 p->tos[toindex].count);
264 write(log, buf2, len);
265 #endif
266 rawarc.raw_frompc = frompc;
267 rawarc.raw_selfpc = p->tos[toindex].selfpc;
268 rawarc.raw_count = p->tos[toindex].count;
269 write(fd, &rawarc, sizeof rawarc);
270 }
271 }
272 close(fd);
273 }
274
275 /*
276 * Control profiling
277 * profiling is what mcount checks to see if
278 * all the data structures are ready.
279 */
280 void
281 moncontrol(mode)
282 int mode;
283 {
284 struct gmonparam *p = &_gmonparam;
285
286 if (mode) {
287 /* start */
288 profil((char *)(void *)p->kcount, (size_t)p->kcountsize,
289 p->lowpc, s_scale);
290 p->state = GMON_PROF_ON;
291 } else {
292 /* stop */
293 profil(NULL, 0, (u_long)0, 0);
294 p->state = GMON_PROF_OFF;
295 }
296 }
297
298 /*
299 * discover the tick frequency of the machine
300 * if something goes wrong, we return 0, an impossible hertz.
301 */
302 static int
303 hertz()
304 {
305 struct itimerval tim;
306
307 tim.it_interval.tv_sec = 0;
308 tim.it_interval.tv_usec = 1;
309 tim.it_value.tv_sec = 0;
310 tim.it_value.tv_usec = 0;
311 setitimer(ITIMER_REAL, &tim, 0);
312 setitimer(ITIMER_REAL, 0, &tim);
313 if (tim.it_interval.tv_usec < 2)
314 return(0);
315 return (int)(1000000 / tim.it_interval.tv_usec);
316 }
317