1 /* $NetBSD: gmon.c,v 1.16 2000/12/20 20:55:23 christos Exp $ */ 2 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #if !defined(lint) && defined(LIBC_SCCS) 38 #if 0 39 static char sccsid[] = "@(#)gmon.c 8.1 (Berkeley) 6/4/93"; 40 #else 41 __RCSID("$NetBSD: gmon.c,v 1.16 2000/12/20 20:55:23 christos Exp $"); 42 #endif 43 #endif 44 45 #include "namespace.h" 46 #include <sys/param.h> 47 #include <sys/time.h> 48 #include <sys/gmon.h> 49 #include <sys/sysctl.h> 50 51 #include <stdio.h> 52 #include <stdlib.h> 53 #include <fcntl.h> 54 #include <limits.h> 55 #include <unistd.h> 56 #include <err.h> 57 #include "extern.h" 58 59 extern char *__progname; 60 61 struct gmonparam _gmonparam = { GMON_PROF_OFF }; 62 63 static u_int s_scale; 64 /* see profil(2) where this is describe (incorrectly) */ 65 #define SCALE_1_TO_1 0x10000L 66 67 #define ERR(s) write(STDERR_FILENO, s, sizeof(s)) 68 69 void moncontrol __P((int)); 70 void monstartup __P((u_long, u_long)); 71 void _mcleanup __P((void)); 72 static int hertz __P((void)); 73 74 75 void 76 monstartup(lowpc, highpc) 77 u_long lowpc; 78 u_long highpc; 79 { 80 long o; 81 char *cp; 82 struct gmonparam *p = &_gmonparam; 83 84 /* 85 * round lowpc and highpc to multiples of the density we're using 86 * so the rest of the scaling (here and in gprof) stays in ints. 87 */ 88 p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER)); 89 p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER)); 90 p->textsize = p->highpc - p->lowpc; 91 p->kcountsize = p->textsize / HISTFRACTION; 92 p->hashfraction = HASHFRACTION; 93 p->fromssize = p->textsize / p->hashfraction; 94 p->tolimit = p->textsize * ARCDENSITY / 100; 95 if (p->tolimit < MINARCS) 96 p->tolimit = MINARCS; 97 else if (p->tolimit > MAXARCS) 98 p->tolimit = MAXARCS; 99 p->tossize = p->tolimit * sizeof(struct tostruct); 100 101 cp = sbrk((intptr_t)(p->kcountsize + p->fromssize + p->tossize)); 102 if (cp == (char *)-1) { 103 ERR("monstartup: out of memory\n"); 104 return; 105 } 106 #ifdef notdef 107 memset(cp, 0, p->kcountsize + p->fromssize + p->tossize); 108 #endif 109 p->tos = (struct tostruct *)(void *)cp; 110 cp += (size_t)p->tossize; 111 p->kcount = (u_short *)(void *)cp; 112 cp += (size_t)p->kcountsize; 113 p->froms = (u_short *)(void *)cp; 114 115 __minbrk = sbrk((intptr_t)0); 116 p->tos[0].link = 0; 117 118 o = p->highpc - p->lowpc; 119 if (p->kcountsize < o) { 120 #ifndef notdef 121 s_scale = ((float)p->kcountsize / o ) * SCALE_1_TO_1; 122 #else /* avoid floating point */ 123 int quot = o / p->kcountsize; 124 125 if (quot >= 0x10000) 126 s_scale = 1; 127 else if (quot >= 0x100) 128 s_scale = 0x10000 / quot; 129 else if (o >= 0x800000) 130 s_scale = 0x1000000 / (o / (p->kcountsize >> 8)); 131 else 132 s_scale = 0x1000000 / ((o << 8) / p->kcountsize); 133 #endif 134 } else 135 s_scale = SCALE_1_TO_1; 136 137 moncontrol(1); 138 } 139 140 void 141 _mcleanup() 142 { 143 int fd; 144 int fromindex; 145 int endfrom; 146 u_long frompc; 147 int toindex; 148 struct rawarc rawarc; 149 struct gmonparam *p = &_gmonparam; 150 struct gmonhdr gmonhdr, *hdr; 151 struct clockinfo clockinfo; 152 int mib[2]; 153 size_t size; 154 char *profdir; 155 char *proffile; 156 char buf[PATH_MAX]; 157 int len = sizeof(buf) - 1; 158 #ifdef DEBUG 159 int log, len; 160 char buf2[200]; 161 #endif 162 163 if (p->state == GMON_PROF_ERROR) 164 ERR("_mcleanup: tos overflow\n"); 165 166 size = sizeof(clockinfo); 167 mib[0] = CTL_KERN; 168 mib[1] = KERN_CLOCKRATE; 169 if (sysctl(mib, 2, &clockinfo, &size, NULL, 0) < 0) { 170 /* 171 * Best guess 172 */ 173 clockinfo.profhz = hertz(); 174 } else if (clockinfo.profhz == 0) { 175 if (clockinfo.hz != 0) 176 clockinfo.profhz = clockinfo.hz; 177 else 178 clockinfo.profhz = hertz(); 179 } 180 181 moncontrol(0); 182 183 if ((profdir = getenv("PROFDIR")) != NULL) { 184 char *s, *t; 185 pid_t pid; 186 long divisor; 187 188 /* If PROFDIR contains a null value, no profiling 189 output is produced */ 190 if (*profdir == '\0') { 191 return; 192 } 193 194 t = buf; 195 s = profdir; 196 while ((*t = *s) != '\0') { 197 if (len-- == 0) { 198 warnx("_mcleanup: internal buffer overflow, PROFDIR too long"); 199 return; 200 } 201 t++; 202 s++; 203 } 204 *t++ = '/'; 205 206 /* 207 * Copy and convert pid from a pid_t to a string. For 208 * best performance, divisor should be initialized to 209 * the largest power of 10 less than PID_MAX. 210 */ 211 pid = getpid(); 212 divisor=10000; 213 while (divisor > pid) divisor /= 10; /* skip leading zeros */ 214 do { 215 *t++ = (char)((pid/divisor) + '0'); 216 pid %= (pid_t)divisor; 217 } while (divisor /= 10); 218 *t++ = '.'; 219 220 s = __progname; 221 while ((*t++ = *s++) != '\0') 222 ; 223 224 proffile = buf; 225 } else { 226 proffile = "gmon.out"; 227 } 228 229 fd = open(proffile , O_CREAT|O_TRUNC|O_WRONLY, 0666); 230 if (fd < 0) { 231 warn("mcount: Cannot open `%s'", proffile); 232 return; 233 } 234 #ifdef DEBUG 235 log = open("gmon.log", O_CREAT|O_TRUNC|O_WRONLY, 0664); 236 if (log < 0) { 237 warn("mcount: Cannot open `gmon.log'"); 238 return; 239 } 240 len = snprintf(buf2, sizeof buf2, "[mcleanup1] kcount 0x%x ssiz %d\n", 241 p->kcount, p->kcountsize); 242 write(log, buf2, len); 243 #endif 244 hdr = (struct gmonhdr *)&gmonhdr; 245 hdr->lpc = p->lowpc; 246 hdr->hpc = p->highpc; 247 hdr->ncnt = (int)(p->kcountsize + sizeof(gmonhdr)); 248 hdr->version = GMONVERSION; 249 hdr->profrate = clockinfo.profhz; 250 (void)write(fd, hdr, sizeof *hdr); 251 (void)write(fd, p->kcount, (size_t)p->kcountsize); 252 endfrom = (int)(p->fromssize / sizeof(*p->froms)); 253 for (fromindex = 0; fromindex < endfrom; fromindex++) { 254 if (p->froms[fromindex] == 0) 255 continue; 256 257 frompc = p->lowpc; 258 frompc += fromindex * p->hashfraction * sizeof(*p->froms); 259 for (toindex = p->froms[fromindex]; toindex != 0; 260 toindex = p->tos[toindex].link) { 261 #ifdef DEBUG 262 len = snprintf(buf2, sizeof buf2, 263 "[mcleanup2] frompc 0x%x selfpc 0x%x count %d\n" , 264 frompc, p->tos[toindex].selfpc, 265 p->tos[toindex].count); 266 write(log, buf2, len); 267 #endif 268 rawarc.raw_frompc = frompc; 269 rawarc.raw_selfpc = p->tos[toindex].selfpc; 270 rawarc.raw_count = p->tos[toindex].count; 271 write(fd, &rawarc, sizeof rawarc); 272 } 273 } 274 close(fd); 275 } 276 277 /* 278 * Control profiling 279 * profiling is what mcount checks to see if 280 * all the data structures are ready. 281 */ 282 void 283 moncontrol(mode) 284 int mode; 285 { 286 struct gmonparam *p = &_gmonparam; 287 288 if (mode) { 289 /* start */ 290 profil((char *)(void *)p->kcount, (size_t)p->kcountsize, 291 p->lowpc, s_scale); 292 p->state = GMON_PROF_ON; 293 } else { 294 /* stop */ 295 profil(NULL, 0, (u_long)0, 0); 296 p->state = GMON_PROF_OFF; 297 } 298 } 299 300 /* 301 * discover the tick frequency of the machine 302 * if something goes wrong, we return 0, an impossible hertz. 303 */ 304 static int 305 hertz() 306 { 307 struct itimerval tim; 308 309 tim.it_interval.tv_sec = 0; 310 tim.it_interval.tv_usec = 1; 311 tim.it_value.tv_sec = 0; 312 tim.it_value.tv_usec = 0; 313 setitimer(ITIMER_REAL, &tim, 0); 314 setitimer(ITIMER_REAL, 0, &tim); 315 if (tim.it_interval.tv_usec < 2) 316 return(0); 317 return (int)(1000000 / tim.it_interval.tv_usec); 318 } 319