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 * 3. 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 * @(#)gmon.c 8.1 (Berkeley) 6/4/93 30 * $FreeBSD: src/lib/libc/gmon/gmon.c,v 1.22 2007/01/09 00:27:58 imp Exp $ 31 */ 32 33 #include "namespace.h" 34 #include <sys/param.h> 35 #include <sys/time.h> 36 #include <sys/gmon.h> 37 #include <sys/mman.h> 38 #include <sys/sysctl.h> 39 40 #include <err.h> 41 #include <fcntl.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 = { .state = GMON_PROF_OFF }; 51 52 static int s_scale; 53 /* see profil(2) where this is describe (incorrectly) */ 54 #define SCALE_1_TO_1 0x10000L 55 56 #define ERR(s) _write(2, s, sizeof(s)) 57 58 void _mcleanup(void); 59 void moncontrol(int); 60 static int hertz(void); 61 62 void 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 if (p->kcountsize < o) 105 s_scale = ((float)p->kcountsize / o ) * SCALE_1_TO_1; 106 else 107 s_scale = SCALE_1_TO_1; 108 109 moncontrol(1); 110 } 111 112 void 113 _mcleanup(void) 114 { 115 int fd; 116 int fromindex; 117 int endfrom; 118 u_long frompc; 119 int toindex; 120 struct rawarc rawarc; 121 struct gmonparam *p = &_gmonparam; 122 struct gmonhdr gmonhdr, *hdr; 123 struct clockinfo clockinfo; 124 char outname[128]; 125 int mib[2]; 126 size_t size; 127 #ifdef DEBUG 128 int log, len; 129 char buf[200]; 130 #endif 131 132 if (p->state == GMON_PROF_ERROR) 133 ERR("_mcleanup: tos overflow\n"); 134 135 size = sizeof(clockinfo); 136 mib[0] = CTL_KERN; 137 mib[1] = KERN_CLOCKRATE; 138 if (sysctl(mib, 2, &clockinfo, &size, NULL, 0) < 0) { 139 /* 140 * Best guess 141 */ 142 clockinfo.profhz = hertz(); 143 } else if (clockinfo.profhz == 0) { 144 if (clockinfo.hz != 0) 145 clockinfo.profhz = clockinfo.hz; 146 else 147 clockinfo.profhz = hertz(); 148 } 149 150 moncontrol(0); 151 snprintf(outname, sizeof(outname), "%s.gmon", _getprogname()); 152 fd = _open(outname, O_CREAT|O_TRUNC|O_WRONLY|O_CLOEXEC, 0666); 153 if (fd < 0) { 154 _warn("_mcleanup: %s", outname); 155 return; 156 } 157 #ifdef DEBUG 158 log = _open("gmon.log", O_CREAT|O_TRUNC|O_WRONLY|O_CLOEXEC, 0664); 159 if (log < 0) { 160 _warn("_mcleanup: gmon.log"); 161 return; 162 } 163 len = sprintf(buf, "[mcleanup1] kcount 0x%p ssiz %lu\n", 164 p->kcount, p->kcountsize); 165 _write(log, buf, len); 166 #endif 167 hdr = (struct gmonhdr *)&gmonhdr; 168 bzero(hdr, sizeof(*hdr)); 169 hdr->lpc = p->lowpc; 170 hdr->hpc = p->highpc; 171 hdr->ncnt = p->kcountsize + sizeof(gmonhdr); 172 hdr->version = GMONVERSION; 173 hdr->profrate = clockinfo.profhz; 174 _write(fd, (char *)hdr, sizeof *hdr); 175 _write(fd, p->kcount, p->kcountsize); 176 endfrom = p->fromssize / sizeof(*p->froms); 177 for (fromindex = 0; fromindex < endfrom; fromindex++) { 178 if (p->froms[fromindex] == 0) 179 continue; 180 181 frompc = p->lowpc; 182 frompc += fromindex * p->hashfraction * sizeof(*p->froms); 183 for (toindex = p->froms[fromindex]; toindex != 0; 184 toindex = p->tos[toindex].link) { 185 #ifdef DEBUG 186 len = sprintf(buf, 187 "[mcleanup2] frompc 0x%lx selfpc 0x%lx count %lu\n" , 188 frompc, p->tos[toindex].selfpc, 189 p->tos[toindex].count); 190 _write(log, buf, len); 191 #endif 192 rawarc.raw_frompc = frompc; 193 rawarc.raw_selfpc = p->tos[toindex].selfpc; 194 rawarc.raw_count = p->tos[toindex].count; 195 _write(fd, &rawarc, sizeof rawarc); 196 } 197 } 198 _close(fd); 199 } 200 201 /* 202 * Control profiling 203 * profiling is what mcount checks to see if 204 * all the data structures are ready. 205 */ 206 void 207 moncontrol(int mode) 208 { 209 struct gmonparam *p = &_gmonparam; 210 211 if (mode) { 212 /* start */ 213 profil((char *)p->kcount, p->kcountsize, p->lowpc, s_scale); 214 p->state = GMON_PROF_ON; 215 } else { 216 /* stop */ 217 profil(NULL, 0, 0, 0); 218 p->state = GMON_PROF_OFF; 219 } 220 } 221 222 /* 223 * discover the tick frequency of the machine 224 * if something goes wrong, we return 0, an impossible hertz. 225 */ 226 static int 227 hertz(void) 228 { 229 struct itimerval tim; 230 231 tim.it_interval.tv_sec = 0; 232 tim.it_interval.tv_usec = 1; 233 tim.it_value.tv_sec = 0; 234 tim.it_value.tv_usec = 0; 235 setitimer(ITIMER_REAL, &tim, 0); 236 setitimer(ITIMER_REAL, 0, &tim); 237 if (tim.it_interval.tv_usec < 2) 238 return(0); 239 return (1000000 / tim.it_interval.tv_usec); 240 } 241