1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
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. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include "namespace.h"
33 #include <sys/param.h>
34 #include <sys/time.h>
35 #include <sys/gmon.h>
36 #include <sys/mman.h>
37 #include <sys/sysctl.h>
38
39 #include <err.h>
40 #include <fcntl.h>
41 #include <inttypes.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <unistd.h>
46 #include "un-namespace.h"
47
48 #include "libc_private.h"
49
50 struct gmonparam _gmonparam = { GMON_PROF_OFF };
51
52 static int s_scale;
53 /* See profil(2) where this is described (incorrectly). */
54 #define SCALE_SHIFT 16
55
56 #define ERR(s) _write(2, s, sizeof(s))
57
58 void moncontrol(int);
59 static int hertz(void);
60 void _mcleanup(void);
61
62 void
monstartup(u_long lowpc,u_long highpc)63 monstartup(u_long lowpc, u_long highpc)
64 {
65 int o;
66 char *cp;
67 struct gmonparam *p = &_gmonparam;
68
69 /*
70 * round lowpc and highpc to multiples of the density we're using
71 * so the rest of the scaling (here and in gprof) stays in ints.
72 */
73 p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER));
74 p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER));
75 p->textsize = p->highpc - p->lowpc;
76 p->kcountsize = p->textsize / HISTFRACTION;
77 p->hashfraction = HASHFRACTION;
78 p->fromssize = p->textsize / HASHFRACTION;
79 p->tolimit = p->textsize * ARCDENSITY / 100;
80 if (p->tolimit < MINARCS)
81 p->tolimit = MINARCS;
82 else if (p->tolimit > MAXARCS)
83 p->tolimit = MAXARCS;
84 p->tossize = p->tolimit * sizeof(struct tostruct);
85
86 cp = mmap(NULL, p->kcountsize + p->fromssize + p->tossize,
87 PROT_READ | PROT_WRITE, MAP_ANON, -1, 0);
88 if (cp == MAP_FAILED) {
89 ERR("monstartup: out of memory\n");
90 return;
91 }
92 #ifdef notdef
93 bzero(cp, p->kcountsize + p->fromssize + p->tossize);
94 #endif
95 p->tos = (struct tostruct *)cp;
96 cp += p->tossize;
97 p->kcount = (u_short *)cp;
98 cp += p->kcountsize;
99 p->froms = (u_short *)cp;
100
101 p->tos[0].link = 0;
102
103 o = p->highpc - p->lowpc;
104 s_scale = (p->kcountsize < o) ?
105 ((uintmax_t)p->kcountsize << SCALE_SHIFT) / o : (1 << SCALE_SHIFT);
106 moncontrol(1);
107 }
108
109 void
_mcleanup(void)110 _mcleanup(void)
111 {
112 int fd;
113 int fromindex;
114 int endfrom;
115 u_long frompc;
116 int toindex;
117 struct rawarc rawarc;
118 struct gmonparam *p = &_gmonparam;
119 struct gmonhdr gmonhdr, *hdr;
120 struct clockinfo clockinfo;
121 char outname[128];
122 int mib[2];
123 size_t size;
124 #ifdef DEBUG
125 int log, len;
126 char buf[200];
127 #endif
128
129 if (p->state == GMON_PROF_ERROR)
130 ERR("_mcleanup: tos overflow\n");
131
132 size = sizeof(clockinfo);
133 mib[0] = CTL_KERN;
134 mib[1] = KERN_CLOCKRATE;
135 if (sysctl(mib, 2, &clockinfo, &size, NULL, 0) < 0) {
136 /*
137 * Best guess
138 */
139 clockinfo.profhz = hertz();
140 } else if (clockinfo.profhz == 0) {
141 if (clockinfo.hz != 0)
142 clockinfo.profhz = clockinfo.hz;
143 else
144 clockinfo.profhz = hertz();
145 }
146
147 moncontrol(0);
148 if (getenv("PROFIL_USE_PID"))
149 snprintf(outname, sizeof(outname), "%s.%d.gmon",
150 _getprogname(), getpid());
151 else
152 snprintf(outname, sizeof(outname), "%s.gmon", _getprogname());
153
154 fd = _open(outname, O_CREAT|O_TRUNC|O_WRONLY|O_CLOEXEC, 0666);
155 if (fd < 0) {
156 _warn("_mcleanup: %s", outname);
157 return;
158 }
159 #ifdef DEBUG
160 log = _open("gmon.log", O_CREAT|O_TRUNC|O_WRONLY|O_CLOEXEC, 0664);
161 if (log < 0) {
162 _warn("_mcleanup: gmon.log");
163 return;
164 }
165 len = sprintf(buf, "[mcleanup1] kcount 0x%p ssiz %lu\n",
166 p->kcount, p->kcountsize);
167 _write(log, buf, len);
168 #endif
169 hdr = (struct gmonhdr *)&gmonhdr;
170 bzero(hdr, sizeof(*hdr));
171 hdr->lpc = p->lowpc;
172 hdr->hpc = p->highpc;
173 hdr->ncnt = p->kcountsize + sizeof(gmonhdr);
174 hdr->version = GMONVERSION;
175 hdr->profrate = clockinfo.profhz;
176 _write(fd, (char *)hdr, sizeof *hdr);
177 _write(fd, p->kcount, p->kcountsize);
178 endfrom = p->fromssize / sizeof(*p->froms);
179 for (fromindex = 0; fromindex < endfrom; fromindex++) {
180 if (p->froms[fromindex] == 0)
181 continue;
182
183 frompc = p->lowpc;
184 frompc += fromindex * p->hashfraction * sizeof(*p->froms);
185 for (toindex = p->froms[fromindex]; toindex != 0;
186 toindex = p->tos[toindex].link) {
187 #ifdef DEBUG
188 len = sprintf(buf,
189 "[mcleanup2] frompc 0x%lx selfpc 0x%lx count %lu\n" ,
190 frompc, p->tos[toindex].selfpc,
191 p->tos[toindex].count);
192 _write(log, buf, len);
193 #endif
194 rawarc.raw_frompc = frompc;
195 rawarc.raw_selfpc = p->tos[toindex].selfpc;
196 rawarc.raw_count = p->tos[toindex].count;
197 _write(fd, &rawarc, sizeof rawarc);
198 }
199 }
200 _close(fd);
201 }
202
203 /*
204 * Control profiling
205 * profiling is what mcount checks to see if
206 * all the data structures are ready.
207 */
208 void
moncontrol(int mode)209 moncontrol(int mode)
210 {
211 struct gmonparam *p = &_gmonparam;
212
213 if (mode) {
214 /* start */
215 profil((char *)p->kcount, p->kcountsize, p->lowpc, s_scale);
216 p->state = GMON_PROF_ON;
217 } else {
218 /* stop */
219 profil((char *)0, 0, 0, 0);
220 p->state = GMON_PROF_OFF;
221 }
222 }
223
224 /*
225 * discover the tick frequency of the machine
226 * if something goes wrong, we return 0, an impossible hertz.
227 */
228 static int
hertz(void)229 hertz(void)
230 {
231 struct itimerval tim;
232
233 tim.it_interval.tv_sec = 0;
234 tim.it_interval.tv_usec = 1;
235 tim.it_value.tv_sec = 0;
236 tim.it_value.tv_usec = 0;
237 setitimer(ITIMER_REAL, &tim, 0);
238 setitimer(ITIMER_REAL, 0, &tim);
239 if (tim.it_interval.tv_usec < 2)
240 return(0);
241 return (1000000 / tim.it_interval.tv_usec);
242 }
243