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 30 #if !defined(lint) && defined(LIBC_SCCS) 31 static char rcsid[] = "$OpenBSD: gmon.c,v 1.17 2005/03/23 19:32:09 otto Exp $"; 32 #endif 33 34 #include <sys/param.h> 35 #include <sys/time.h> 36 #include <sys/gmon.h> 37 #include <sys/sysctl.h> 38 39 #include <stdio.h> 40 #include <stdlib.h> 41 #include <string.h> 42 #include <fcntl.h> 43 #include <limits.h> 44 #include <unistd.h> 45 46 extern char *minbrk __asm ("minbrk"); 47 48 struct gmonparam _gmonparam = { GMON_PROF_OFF }; 49 50 static int s_scale; 51 /* see profil(2) where this is describe (incorrectly) */ 52 #define SCALE_1_TO_1 0x10000L 53 54 #define ERR(s) write(STDERR_FILENO, s, sizeof(s)) 55 56 void moncontrol(int); 57 static int hertz(void); 58 void monstartup(u_long lowpc, u_long highpc); 59 void _mcleanup(void); 60 61 void 62 monstartup(u_long lowpc, u_long highpc) 63 { 64 int o; 65 char *cp; 66 struct gmonparam *p = &_gmonparam; 67 68 /* 69 * round lowpc and highpc to multiples of the density we're using 70 * so the rest of the scaling (here and in gprof) stays in ints. 71 */ 72 p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER)); 73 p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER)); 74 p->textsize = p->highpc - p->lowpc; 75 p->kcountsize = p->textsize / HISTFRACTION; 76 p->hashfraction = HASHFRACTION; 77 p->fromssize = p->textsize / p->hashfraction; 78 p->tolimit = p->textsize * ARCDENSITY / 100; 79 if (p->tolimit < MINARCS) 80 p->tolimit = MINARCS; 81 else if (p->tolimit > MAXARCS) 82 p->tolimit = MAXARCS; 83 p->tossize = p->tolimit * sizeof(struct tostruct); 84 85 cp = sbrk(p->kcountsize + p->fromssize + p->tossize); 86 if (cp == (char *)-1) { 87 ERR("monstartup: out of memory\n"); 88 return; 89 } 90 #ifdef notdef 91 bzero(cp, p->kcountsize + p->fromssize + p->tossize); 92 #endif 93 p->tos = (struct tostruct *)cp; 94 cp += p->tossize; 95 p->kcount = (u_short *)cp; 96 cp += p->kcountsize; 97 p->froms = (u_short *)cp; 98 99 minbrk = sbrk(0); 100 p->tos[0].link = 0; 101 102 o = p->highpc - p->lowpc; 103 if (p->kcountsize < o) { 104 #ifndef notdef 105 s_scale = ((float)p->kcountsize / o ) * SCALE_1_TO_1; 106 #else /* avoid floating point */ 107 int quot = o / p->kcountsize; 108 109 if (quot >= 0x10000) 110 s_scale = 1; 111 else if (quot >= 0x100) 112 s_scale = 0x10000 / quot; 113 else if (o >= 0x800000) 114 s_scale = 0x1000000 / (o / (p->kcountsize >> 8)); 115 else 116 s_scale = 0x1000000 / ((o << 8) / p->kcountsize); 117 #endif 118 } else 119 s_scale = SCALE_1_TO_1; 120 121 moncontrol(1); 122 } 123 124 void 125 _mcleanup(void) 126 { 127 int fd; 128 int fromindex; 129 int endfrom; 130 u_long frompc; 131 int toindex; 132 struct rawarc rawarc; 133 struct gmonparam *p = &_gmonparam; 134 struct gmonhdr gmonhdr, *hdr; 135 struct clockinfo clockinfo; 136 int mib[2]; 137 size_t size; 138 char *profdir; 139 char *proffile; 140 char buf[PATH_MAX]; 141 #ifdef DEBUG 142 int log, len; 143 char dbuf[200]; 144 #endif 145 146 if (p->state == GMON_PROF_ERROR) 147 ERR("_mcleanup: tos overflow\n"); 148 149 size = sizeof(clockinfo); 150 mib[0] = CTL_KERN; 151 mib[1] = KERN_CLOCKRATE; 152 if (sysctl(mib, 2, &clockinfo, &size, NULL, 0) < 0) { 153 /* 154 * Best guess 155 */ 156 clockinfo.profhz = hertz(); 157 } else if (clockinfo.profhz == 0) { 158 if (clockinfo.hz != 0) 159 clockinfo.profhz = clockinfo.hz; 160 else 161 clockinfo.profhz = hertz(); 162 } 163 164 moncontrol(0); 165 166 if (issetugid() == 0 && (profdir = getenv("PROFDIR")) != NULL) { 167 extern char *__progname; 168 char *s, *t, *limit; 169 pid_t pid; 170 long divisor; 171 172 /* If PROFDIR contains a null value, no profiling 173 output is produced */ 174 if (*profdir == '\0') { 175 return; 176 } 177 178 limit = buf + sizeof buf - 1 - 10 - 1 - 179 strlen(__progname) - 1; 180 t = buf; 181 s = profdir; 182 while((*t = *s) != '\0' && t < limit) { 183 t++; 184 s++; 185 } 186 *t++ = '/'; 187 188 /* 189 * Copy and convert pid from a pid_t to a string. For 190 * best performance, divisor should be initialized to 191 * the largest power of 10 less than PID_MAX. 192 */ 193 pid = getpid(); 194 divisor=10000; 195 while (divisor > pid) divisor /= 10; /* skip leading zeros */ 196 do { 197 *t++ = (pid/divisor) + '0'; 198 pid %= divisor; 199 } while (divisor /= 10); 200 *t++ = '.'; 201 202 s = __progname; 203 while ((*t++ = *s++) != '\0') 204 ; 205 206 proffile = buf; 207 } else { 208 proffile = "gmon.out"; 209 } 210 211 fd = open(proffile , O_CREAT|O_TRUNC|O_WRONLY, 0664); 212 if (fd < 0) { 213 perror( proffile ); 214 return; 215 } 216 #ifdef DEBUG 217 log = open("gmon.log", O_CREAT|O_TRUNC|O_WRONLY, 0664); 218 if (log < 0) { 219 perror("mcount: gmon.log"); 220 return; 221 } 222 len = snprintf(dbuf, sizeof dbuf, "[mcleanup1] kcount 0x%x ssiz %d\n", 223 p->kcount, p->kcountsize); 224 write(log, dbuf, len); 225 #endif 226 hdr = (struct gmonhdr *)&gmonhdr; 227 bzero(hdr, sizeof(*hdr)); 228 hdr->lpc = p->lowpc; 229 hdr->hpc = p->highpc; 230 hdr->ncnt = p->kcountsize + sizeof(gmonhdr); 231 hdr->version = GMONVERSION; 232 hdr->profrate = clockinfo.profhz; 233 write(fd, (char *)hdr, sizeof *hdr); 234 write(fd, p->kcount, p->kcountsize); 235 endfrom = p->fromssize / sizeof(*p->froms); 236 for (fromindex = 0; fromindex < endfrom; fromindex++) { 237 if (p->froms[fromindex] == 0) 238 continue; 239 240 frompc = p->lowpc; 241 frompc += fromindex * p->hashfraction * sizeof(*p->froms); 242 for (toindex = p->froms[fromindex]; toindex != 0; 243 toindex = p->tos[toindex].link) { 244 #ifdef DEBUG 245 len = snprintf(dbuf, sizeof dbuf, 246 "[mcleanup2] frompc 0x%x selfpc 0x%x count %d\n" , 247 frompc, p->tos[toindex].selfpc, 248 p->tos[toindex].count); 249 write(log, dbuf, len); 250 #endif 251 rawarc.raw_frompc = frompc; 252 rawarc.raw_selfpc = p->tos[toindex].selfpc; 253 rawarc.raw_count = p->tos[toindex].count; 254 write(fd, &rawarc, sizeof rawarc); 255 } 256 } 257 close(fd); 258 } 259 260 /* 261 * Control profiling 262 * profiling is what mcount checks to see if 263 * all the data structures are ready. 264 */ 265 void 266 moncontrol(int mode) 267 { 268 struct gmonparam *p = &_gmonparam; 269 270 if (mode) { 271 /* start */ 272 profil((char *)p->kcount, p->kcountsize, p->lowpc, 273 s_scale); 274 p->state = GMON_PROF_ON; 275 } else { 276 /* stop */ 277 profil((char *)0, 0, 0, 0); 278 p->state = GMON_PROF_OFF; 279 } 280 } 281 282 /* 283 * discover the tick frequency of the machine 284 * if something goes wrong, we return 0, an impossible hertz. 285 */ 286 static int 287 hertz(void) 288 { 289 struct itimerval tim; 290 291 tim.it_interval.tv_sec = 0; 292 tim.it_interval.tv_usec = 1; 293 tim.it_value.tv_sec = 0; 294 tim.it_value.tv_usec = 0; 295 setitimer(ITIMER_REAL, &tim, 0); 296 setitimer(ITIMER_REAL, 0, &tim); 297 if (tim.it_interval.tv_usec < 2) 298 return(0); 299 return (1000000 / tim.it_interval.tv_usec); 300 } 301 302 303