1 /*-
2 * Copyright (c) 1983, 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 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30 #if defined(LIBC_SCCS) && !defined(lint)
31 static char sccsid[] = "@(#)gmon.c 8.1 (Berkeley) 6/4/93";
32 #endif
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35
36 #include "namespace.h"
37 #include <sys/param.h>
38 #include <sys/time.h>
39 #include <sys/gmon.h>
40 #include <sys/mman.h>
41 #include <sys/sysctl.h>
42
43 #include <err.h>
44 #include <fcntl.h>
45 #include <inttypes.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <unistd.h>
50 #include "un-namespace.h"
51
52 #include "libc_private.h"
53
54 struct gmonparam _gmonparam = { GMON_PROF_OFF };
55
56 static int s_scale;
57 /* See profil(2) where this is described (incorrectly). */
58 #define SCALE_SHIFT 16
59
60 #define ERR(s) _write(2, s, sizeof(s))
61
62 void moncontrol(int);
63 static int hertz(void);
64 void _mcleanup(void);
65
66 void
monstartup(u_long lowpc,u_long highpc)67 monstartup(u_long lowpc, u_long highpc)
68 {
69 int o;
70 char *cp;
71 struct gmonparam *p = &_gmonparam;
72
73 /*
74 * round lowpc and highpc to multiples of the density we're using
75 * so the rest of the scaling (here and in gprof) stays in ints.
76 */
77 p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER));
78 p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER));
79 p->textsize = p->highpc - p->lowpc;
80 p->kcountsize = p->textsize / HISTFRACTION;
81 p->hashfraction = HASHFRACTION;
82 p->fromssize = p->textsize / HASHFRACTION;
83 p->tolimit = p->textsize * ARCDENSITY / 100;
84 if (p->tolimit < MINARCS)
85 p->tolimit = MINARCS;
86 else if (p->tolimit > MAXARCS)
87 p->tolimit = MAXARCS;
88 p->tossize = p->tolimit * sizeof(struct tostruct);
89
90 cp = mmap(NULL, p->kcountsize + p->fromssize + p->tossize,
91 PROT_READ | PROT_WRITE, MAP_ANON, -1, 0);
92 if (cp == MAP_FAILED) {
93 ERR("monstartup: out of memory\n");
94 return;
95 }
96 #ifdef notdef
97 bzero(cp, p->kcountsize + p->fromssize + p->tossize);
98 #endif
99 p->tos = (struct tostruct *)cp;
100 cp += p->tossize;
101 p->kcount = (u_short *)cp;
102 cp += p->kcountsize;
103 p->froms = (u_short *)cp;
104
105 p->tos[0].link = 0;
106
107 o = p->highpc - p->lowpc;
108 s_scale = (p->kcountsize < o) ?
109 ((uintmax_t)p->kcountsize << SCALE_SHIFT) / o : (1 << SCALE_SHIFT);
110 moncontrol(1);
111 }
112
113 void
_mcleanup(void)114 _mcleanup(void)
115 {
116 int fd;
117 int fromindex;
118 int endfrom;
119 u_long frompc;
120 int toindex;
121 struct rawarc rawarc;
122 struct gmonparam *p = &_gmonparam;
123 struct gmonhdr gmonhdr, *hdr;
124 struct clockinfo clockinfo;
125 char outname[128];
126 int mib[2];
127 size_t size;
128 #ifdef DEBUG
129 int log, len;
130 char buf[200];
131 #endif
132
133 if (p->state == GMON_PROF_ERROR)
134 ERR("_mcleanup: tos overflow\n");
135
136 size = sizeof(clockinfo);
137 mib[0] = CTL_KERN;
138 mib[1] = KERN_CLOCKRATE;
139 if (sysctl(mib, 2, &clockinfo, &size, NULL, 0) < 0) {
140 /*
141 * Best guess
142 */
143 clockinfo.profhz = hertz();
144 } else if (clockinfo.profhz == 0) {
145 if (clockinfo.hz != 0)
146 clockinfo.profhz = clockinfo.hz;
147 else
148 clockinfo.profhz = hertz();
149 }
150
151 moncontrol(0);
152 if (getenv("PROFIL_USE_PID"))
153 snprintf(outname, sizeof(outname), "%s.%d.gmon",
154 _getprogname(), getpid());
155 else
156 snprintf(outname, sizeof(outname), "%s.gmon", _getprogname());
157
158 fd = _open(outname, O_CREAT|O_TRUNC|O_WRONLY|O_CLOEXEC, 0666);
159 if (fd < 0) {
160 _warn("_mcleanup: %s", outname);
161 return;
162 }
163 #ifdef DEBUG
164 log = _open("gmon.log", O_CREAT|O_TRUNC|O_WRONLY|O_CLOEXEC, 0664);
165 if (log < 0) {
166 _warn("_mcleanup: gmon.log");
167 return;
168 }
169 len = sprintf(buf, "[mcleanup1] kcount 0x%p ssiz %lu\n",
170 p->kcount, p->kcountsize);
171 _write(log, buf, len);
172 #endif
173 hdr = (struct gmonhdr *)&gmonhdr;
174 bzero(hdr, sizeof(*hdr));
175 hdr->lpc = p->lowpc;
176 hdr->hpc = p->highpc;
177 hdr->ncnt = p->kcountsize + sizeof(gmonhdr);
178 hdr->version = GMONVERSION;
179 hdr->profrate = clockinfo.profhz;
180 _write(fd, (char *)hdr, sizeof *hdr);
181 _write(fd, p->kcount, p->kcountsize);
182 endfrom = p->fromssize / sizeof(*p->froms);
183 for (fromindex = 0; fromindex < endfrom; fromindex++) {
184 if (p->froms[fromindex] == 0)
185 continue;
186
187 frompc = p->lowpc;
188 frompc += fromindex * p->hashfraction * sizeof(*p->froms);
189 for (toindex = p->froms[fromindex]; toindex != 0;
190 toindex = p->tos[toindex].link) {
191 #ifdef DEBUG
192 len = sprintf(buf,
193 "[mcleanup2] frompc 0x%lx selfpc 0x%lx count %lu\n" ,
194 frompc, p->tos[toindex].selfpc,
195 p->tos[toindex].count);
196 _write(log, buf, len);
197 #endif
198 rawarc.raw_frompc = frompc;
199 rawarc.raw_selfpc = p->tos[toindex].selfpc;
200 rawarc.raw_count = p->tos[toindex].count;
201 _write(fd, &rawarc, sizeof rawarc);
202 }
203 }
204 _close(fd);
205 }
206
207 /*
208 * Control profiling
209 * profiling is what mcount checks to see if
210 * all the data structures are ready.
211 */
212 void
moncontrol(int mode)213 moncontrol(int mode)
214 {
215 struct gmonparam *p = &_gmonparam;
216
217 if (mode) {
218 /* start */
219 profil((char *)p->kcount, p->kcountsize, p->lowpc, s_scale);
220 p->state = GMON_PROF_ON;
221 } else {
222 /* stop */
223 profil((char *)0, 0, 0, 0);
224 p->state = GMON_PROF_OFF;
225 }
226 }
227
228 /*
229 * discover the tick frequency of the machine
230 * if something goes wrong, we return 0, an impossible hertz.
231 */
232 static int
hertz(void)233 hertz(void)
234 {
235 struct itimerval tim;
236
237 tim.it_interval.tv_sec = 0;
238 tim.it_interval.tv_usec = 1;
239 tim.it_value.tv_sec = 0;
240 tim.it_value.tv_usec = 0;
241 setitimer(ITIMER_REAL, &tim, 0);
242 setitimer(ITIMER_REAL, 0, &tim);
243 if (tim.it_interval.tv_usec < 2)
244 return(0);
245 return (1000000 / tim.it_interval.tv_usec);
246 }
247