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 #if defined(LIBC_SCCS) && !defined(lint) 33 static char sccsid[] = "@(#)gmon.c 8.1 (Berkeley) 6/4/93"; 34 #endif 35 #include <sys/cdefs.h> 36 __FBSDID("$FreeBSD$"); 37 38 #include "namespace.h" 39 #include <sys/param.h> 40 #include <sys/time.h> 41 #include <sys/gmon.h> 42 #include <sys/mman.h> 43 #include <sys/sysctl.h> 44 45 #include <err.h> 46 #include <fcntl.h> 47 #include <inttypes.h> 48 #include <stdio.h> 49 #include <stdlib.h> 50 #include <string.h> 51 #include <unistd.h> 52 #include "un-namespace.h" 53 54 #include "libc_private.h" 55 56 struct gmonparam _gmonparam = { GMON_PROF_OFF }; 57 58 static int s_scale; 59 /* See profil(2) where this is described (incorrectly). */ 60 #define SCALE_SHIFT 16 61 62 #define ERR(s) _write(2, s, sizeof(s)) 63 64 void moncontrol(int); 65 static int hertz(void); 66 void _mcleanup(void); 67 68 void 69 monstartup(u_long lowpc, u_long highpc) 70 { 71 int o; 72 char *cp; 73 struct gmonparam *p = &_gmonparam; 74 75 /* 76 * round lowpc and highpc to multiples of the density we're using 77 * so the rest of the scaling (here and in gprof) stays in ints. 78 */ 79 p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER)); 80 p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER)); 81 p->textsize = p->highpc - p->lowpc; 82 p->kcountsize = p->textsize / HISTFRACTION; 83 p->hashfraction = HASHFRACTION; 84 p->fromssize = p->textsize / HASHFRACTION; 85 p->tolimit = p->textsize * ARCDENSITY / 100; 86 if (p->tolimit < MINARCS) 87 p->tolimit = MINARCS; 88 else if (p->tolimit > MAXARCS) 89 p->tolimit = MAXARCS; 90 p->tossize = p->tolimit * sizeof(struct tostruct); 91 92 cp = mmap(NULL, p->kcountsize + p->fromssize + p->tossize, 93 PROT_READ | PROT_WRITE, MAP_ANON, -1, 0); 94 if (cp == MAP_FAILED) { 95 ERR("monstartup: out of memory\n"); 96 return; 97 } 98 #ifdef notdef 99 bzero(cp, p->kcountsize + p->fromssize + p->tossize); 100 #endif 101 p->tos = (struct tostruct *)cp; 102 cp += p->tossize; 103 p->kcount = (u_short *)cp; 104 cp += p->kcountsize; 105 p->froms = (u_short *)cp; 106 107 p->tos[0].link = 0; 108 109 o = p->highpc - p->lowpc; 110 s_scale = (p->kcountsize < o) ? 111 ((uintmax_t)p->kcountsize << SCALE_SHIFT) / o : (1 << SCALE_SHIFT); 112 moncontrol(1); 113 } 114 115 void 116 _mcleanup(void) 117 { 118 int fd; 119 int fromindex; 120 int endfrom; 121 u_long frompc; 122 int toindex; 123 struct rawarc rawarc; 124 struct gmonparam *p = &_gmonparam; 125 struct gmonhdr gmonhdr, *hdr; 126 struct clockinfo clockinfo; 127 char outname[128]; 128 int mib[2]; 129 size_t size; 130 #ifdef DEBUG 131 int log, len; 132 char buf[200]; 133 #endif 134 135 if (p->state == GMON_PROF_ERROR) 136 ERR("_mcleanup: tos overflow\n"); 137 138 size = sizeof(clockinfo); 139 mib[0] = CTL_KERN; 140 mib[1] = KERN_CLOCKRATE; 141 if (sysctl(mib, 2, &clockinfo, &size, NULL, 0) < 0) { 142 /* 143 * Best guess 144 */ 145 clockinfo.profhz = hertz(); 146 } else if (clockinfo.profhz == 0) { 147 if (clockinfo.hz != 0) 148 clockinfo.profhz = clockinfo.hz; 149 else 150 clockinfo.profhz = hertz(); 151 } 152 153 moncontrol(0); 154 if (getenv("PROFIL_USE_PID")) 155 snprintf(outname, sizeof(outname), "%s.%d.gmon", 156 _getprogname(), getpid()); 157 else 158 snprintf(outname, sizeof(outname), "%s.gmon", _getprogname()); 159 160 fd = _open(outname, O_CREAT|O_TRUNC|O_WRONLY|O_CLOEXEC, 0666); 161 if (fd < 0) { 162 _warn("_mcleanup: %s", outname); 163 return; 164 } 165 #ifdef DEBUG 166 log = _open("gmon.log", O_CREAT|O_TRUNC|O_WRONLY|O_CLOEXEC, 0664); 167 if (log < 0) { 168 _warn("_mcleanup: gmon.log"); 169 return; 170 } 171 len = sprintf(buf, "[mcleanup1] kcount 0x%p ssiz %lu\n", 172 p->kcount, p->kcountsize); 173 _write(log, buf, len); 174 #endif 175 hdr = (struct gmonhdr *)&gmonhdr; 176 bzero(hdr, sizeof(*hdr)); 177 hdr->lpc = p->lowpc; 178 hdr->hpc = p->highpc; 179 hdr->ncnt = p->kcountsize + sizeof(gmonhdr); 180 hdr->version = GMONVERSION; 181 hdr->profrate = clockinfo.profhz; 182 _write(fd, (char *)hdr, sizeof *hdr); 183 _write(fd, p->kcount, p->kcountsize); 184 endfrom = p->fromssize / sizeof(*p->froms); 185 for (fromindex = 0; fromindex < endfrom; fromindex++) { 186 if (p->froms[fromindex] == 0) 187 continue; 188 189 frompc = p->lowpc; 190 frompc += fromindex * p->hashfraction * sizeof(*p->froms); 191 for (toindex = p->froms[fromindex]; toindex != 0; 192 toindex = p->tos[toindex].link) { 193 #ifdef DEBUG 194 len = sprintf(buf, 195 "[mcleanup2] frompc 0x%lx selfpc 0x%lx count %lu\n" , 196 frompc, p->tos[toindex].selfpc, 197 p->tos[toindex].count); 198 _write(log, buf, len); 199 #endif 200 rawarc.raw_frompc = frompc; 201 rawarc.raw_selfpc = p->tos[toindex].selfpc; 202 rawarc.raw_count = p->tos[toindex].count; 203 _write(fd, &rawarc, sizeof rawarc); 204 } 205 } 206 _close(fd); 207 } 208 209 /* 210 * Control profiling 211 * profiling is what mcount checks to see if 212 * all the data structures are ready. 213 */ 214 void 215 moncontrol(int mode) 216 { 217 struct gmonparam *p = &_gmonparam; 218 219 if (mode) { 220 /* start */ 221 profil((char *)p->kcount, p->kcountsize, p->lowpc, s_scale); 222 p->state = GMON_PROF_ON; 223 } else { 224 /* stop */ 225 profil((char *)0, 0, 0, 0); 226 p->state = GMON_PROF_OFF; 227 } 228 } 229 230 /* 231 * discover the tick frequency of the machine 232 * if something goes wrong, we return 0, an impossible hertz. 233 */ 234 static int 235 hertz(void) 236 { 237 struct itimerval tim; 238 239 tim.it_interval.tv_sec = 0; 240 tim.it_interval.tv_usec = 1; 241 tim.it_value.tv_sec = 0; 242 tim.it_value.tv_usec = 0; 243 setitimer(ITIMER_REAL, &tim, 0); 244 setitimer(ITIMER_REAL, 0, &tim); 245 if (tim.it_interval.tv_usec < 2) 246 return(0); 247 return (1000000 / tim.it_interval.tv_usec); 248 } 249