gmon.c revision 288009
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 * 4. 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(LIBC_SCCS) && !defined(lint) 31static char sccsid[] = "@(#)gmon.c 8.1 (Berkeley) 6/4/93"; 32#endif 33#include <sys/cdefs.h> 34__FBSDID("$FreeBSD: head/lib/libc/gmon/gmon.c 288009 2015-09-20 03:59:27Z rodrigc $"); 35 36#include "namespace.h" 37#include <sys/param.h> 38#include <sys/time.h> 39#include <sys/gmon.h> 40#include <sys/sysctl.h> 41 42#include <err.h> 43#include <fcntl.h> 44#include <inttypes.h> 45#include <stdio.h> 46#include <stdlib.h> 47#include <string.h> 48#include <unistd.h> 49#include "un-namespace.h" 50 51#include "libc_private.h" 52 53#if defined(__i386__) || defined(__sparc64__) || defined(__amd64__) || (defined(__powerpc__) && !defined(__powerpc64__)) 54extern char *minbrk __asm (".minbrk"); 55#elif defined(__powerpc64__) 56extern char *minbrk __asm ("_minbrk"); 57#else 58extern char *minbrk __asm ("minbrk"); 59#endif 60 61struct gmonparam _gmonparam = { GMON_PROF_OFF }; 62 63static int s_scale; 64/* See profil(2) where this is described (incorrectly). */ 65#define SCALE_SHIFT 16 66 67#define ERR(s) _write(2, s, sizeof(s)) 68 69void moncontrol(int); 70static int hertz(void); 71void _mcleanup(void); 72 73void 74monstartup(u_long lowpc, u_long highpc) 75{ 76 int o; 77 char *cp; 78 struct gmonparam *p = &_gmonparam; 79 80 /* 81 * round lowpc and highpc to multiples of the density we're using 82 * so the rest of the scaling (here and in gprof) stays in ints. 83 */ 84 p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER)); 85 p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER)); 86 p->textsize = p->highpc - p->lowpc; 87 p->kcountsize = p->textsize / HISTFRACTION; 88 p->hashfraction = HASHFRACTION; 89 p->fromssize = p->textsize / HASHFRACTION; 90 p->tolimit = p->textsize * ARCDENSITY / 100; 91 if (p->tolimit < MINARCS) 92 p->tolimit = MINARCS; 93 else if (p->tolimit > MAXARCS) 94 p->tolimit = MAXARCS; 95 p->tossize = p->tolimit * sizeof(struct tostruct); 96 97 cp = sbrk(p->kcountsize + p->fromssize + p->tossize); 98 if (cp == (char *)-1) { 99 ERR("monstartup: out of memory\n"); 100 return; 101 } 102#ifdef notdef 103 bzero(cp, p->kcountsize + p->fromssize + p->tossize); 104#endif 105 p->tos = (struct tostruct *)cp; 106 cp += p->tossize; 107 p->kcount = (u_short *)cp; 108 cp += p->kcountsize; 109 p->froms = (u_short *)cp; 110 111 minbrk = sbrk(0); 112 p->tos[0].link = 0; 113 114 o = p->highpc - p->lowpc; 115 s_scale = (p->kcountsize < o) ? 116 ((uintmax_t)p->kcountsize << SCALE_SHIFT) / o : (1 << SCALE_SHIFT); 117 moncontrol(1); 118} 119 120void 121_mcleanup(void) 122{ 123 int fd; 124 int fromindex; 125 int endfrom; 126 u_long frompc; 127 int toindex; 128 struct rawarc rawarc; 129 struct gmonparam *p = &_gmonparam; 130 struct gmonhdr gmonhdr, *hdr; 131 struct clockinfo clockinfo; 132 char outname[128]; 133 int mib[2]; 134 size_t size; 135#ifdef DEBUG 136 int log, len; 137 char buf[200]; 138#endif 139 140 if (p->state == GMON_PROF_ERROR) 141 ERR("_mcleanup: tos overflow\n"); 142 143 size = sizeof(clockinfo); 144 mib[0] = CTL_KERN; 145 mib[1] = KERN_CLOCKRATE; 146 if (sysctl(mib, 2, &clockinfo, &size, NULL, 0) < 0) { 147 /* 148 * Best guess 149 */ 150 clockinfo.profhz = hertz(); 151 } else if (clockinfo.profhz == 0) { 152 if (clockinfo.hz != 0) 153 clockinfo.profhz = clockinfo.hz; 154 else 155 clockinfo.profhz = hertz(); 156 } 157 158 moncontrol(0); 159 if (getenv("PROFIL_USE_PID")) 160 snprintf(outname, sizeof(outname), "%s.%d.gmon", 161 _getprogname(), getpid()); 162 else 163 snprintf(outname, sizeof(outname), "%s.gmon", _getprogname()); 164 165 fd = _open(outname, O_CREAT|O_TRUNC|O_WRONLY|O_CLOEXEC, 0666); 166 if (fd < 0) { 167 _warn("_mcleanup: %s", outname); 168 return; 169 } 170#ifdef DEBUG 171 log = _open("gmon.log", O_CREAT|O_TRUNC|O_WRONLY|O_CLOEXEC, 0664); 172 if (log < 0) { 173 _warn("_mcleanup: gmon.log"); 174 return; 175 } 176 len = sprintf(buf, "[mcleanup1] kcount 0x%p ssiz %lu\n", 177 p->kcount, p->kcountsize); 178 _write(log, buf, len); 179#endif 180 hdr = (struct gmonhdr *)&gmonhdr; 181 bzero(hdr, sizeof(*hdr)); 182 hdr->lpc = p->lowpc; 183 hdr->hpc = p->highpc; 184 hdr->ncnt = p->kcountsize + sizeof(gmonhdr); 185 hdr->version = GMONVERSION; 186 hdr->profrate = clockinfo.profhz; 187 _write(fd, (char *)hdr, sizeof *hdr); 188 _write(fd, p->kcount, p->kcountsize); 189 endfrom = p->fromssize / sizeof(*p->froms); 190 for (fromindex = 0; fromindex < endfrom; fromindex++) { 191 if (p->froms[fromindex] == 0) 192 continue; 193 194 frompc = p->lowpc; 195 frompc += fromindex * p->hashfraction * sizeof(*p->froms); 196 for (toindex = p->froms[fromindex]; toindex != 0; 197 toindex = p->tos[toindex].link) { 198#ifdef DEBUG 199 len = sprintf(buf, 200 "[mcleanup2] frompc 0x%lx selfpc 0x%lx count %lu\n" , 201 frompc, p->tos[toindex].selfpc, 202 p->tos[toindex].count); 203 _write(log, buf, len); 204#endif 205 rawarc.raw_frompc = frompc; 206 rawarc.raw_selfpc = p->tos[toindex].selfpc; 207 rawarc.raw_count = p->tos[toindex].count; 208 _write(fd, &rawarc, sizeof rawarc); 209 } 210 } 211 _close(fd); 212} 213 214/* 215 * Control profiling 216 * profiling is what mcount checks to see if 217 * all the data structures are ready. 218 */ 219void 220moncontrol(int mode) 221{ 222 struct gmonparam *p = &_gmonparam; 223 224 if (mode) { 225 /* start */ 226 profil((char *)p->kcount, p->kcountsize, p->lowpc, s_scale); 227 p->state = GMON_PROF_ON; 228 } else { 229 /* stop */ 230 profil((char *)0, 0, 0, 0); 231 p->state = GMON_PROF_OFF; 232 } 233} 234 235/* 236 * discover the tick frequency of the machine 237 * if something goes wrong, we return 0, an impossible hertz. 238 */ 239static int 240hertz(void) 241{ 242 struct itimerval tim; 243 244 tim.it_interval.tv_sec = 0; 245 tim.it_interval.tv_usec = 1; 246 tim.it_value.tv_sec = 0; 247 tim.it_value.tv_usec = 0; 248 setitimer(ITIMER_REAL, &tim, 0); 249 setitimer(ITIMER_REAL, 0, &tim); 250 if (tim.it_interval.tv_usec < 2) 251 return(0); 252 return (1000000 / tim.it_interval.tv_usec); 253} 254