freebsd-dev/lib/libc/gmon/gmon.c
Pedro F. Giffuni 8a16b7a18f General further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
2017-11-20 19:49:47 +00:00

249 lines
6.6 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1983, 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)gmon.c 8.1 (Berkeley) 6/4/93";
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "namespace.h"
#include <sys/param.h>
#include <sys/time.h>
#include <sys/gmon.h>
#include <sys/mman.h>
#include <sys/sysctl.h>
#include <err.h>
#include <fcntl.h>
#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "un-namespace.h"
#include "libc_private.h"
struct gmonparam _gmonparam = { GMON_PROF_OFF };
static int s_scale;
/* See profil(2) where this is described (incorrectly). */
#define SCALE_SHIFT 16
#define ERR(s) _write(2, s, sizeof(s))
void moncontrol(int);
static int hertz(void);
void _mcleanup(void);
void
monstartup(u_long lowpc, u_long highpc)
{
int o;
char *cp;
struct gmonparam *p = &_gmonparam;
/*
* round lowpc and highpc to multiples of the density we're using
* so the rest of the scaling (here and in gprof) stays in ints.
*/
p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER));
p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER));
p->textsize = p->highpc - p->lowpc;
p->kcountsize = p->textsize / HISTFRACTION;
p->hashfraction = HASHFRACTION;
p->fromssize = p->textsize / HASHFRACTION;
p->tolimit = p->textsize * ARCDENSITY / 100;
if (p->tolimit < MINARCS)
p->tolimit = MINARCS;
else if (p->tolimit > MAXARCS)
p->tolimit = MAXARCS;
p->tossize = p->tolimit * sizeof(struct tostruct);
cp = mmap(NULL, p->kcountsize + p->fromssize + p->tossize,
PROT_READ | PROT_WRITE, MAP_ANON, -1, 0);
if (cp == MAP_FAILED) {
ERR("monstartup: out of memory\n");
return;
}
#ifdef notdef
bzero(cp, p->kcountsize + p->fromssize + p->tossize);
#endif
p->tos = (struct tostruct *)cp;
cp += p->tossize;
p->kcount = (u_short *)cp;
cp += p->kcountsize;
p->froms = (u_short *)cp;
p->tos[0].link = 0;
o = p->highpc - p->lowpc;
s_scale = (p->kcountsize < o) ?
((uintmax_t)p->kcountsize << SCALE_SHIFT) / o : (1 << SCALE_SHIFT);
moncontrol(1);
}
void
_mcleanup(void)
{
int fd;
int fromindex;
int endfrom;
u_long frompc;
int toindex;
struct rawarc rawarc;
struct gmonparam *p = &_gmonparam;
struct gmonhdr gmonhdr, *hdr;
struct clockinfo clockinfo;
char outname[128];
int mib[2];
size_t size;
#ifdef DEBUG
int log, len;
char buf[200];
#endif
if (p->state == GMON_PROF_ERROR)
ERR("_mcleanup: tos overflow\n");
size = sizeof(clockinfo);
mib[0] = CTL_KERN;
mib[1] = KERN_CLOCKRATE;
if (sysctl(mib, 2, &clockinfo, &size, NULL, 0) < 0) {
/*
* Best guess
*/
clockinfo.profhz = hertz();
} else if (clockinfo.profhz == 0) {
if (clockinfo.hz != 0)
clockinfo.profhz = clockinfo.hz;
else
clockinfo.profhz = hertz();
}
moncontrol(0);
if (getenv("PROFIL_USE_PID"))
snprintf(outname, sizeof(outname), "%s.%d.gmon",
_getprogname(), getpid());
else
snprintf(outname, sizeof(outname), "%s.gmon", _getprogname());
fd = _open(outname, O_CREAT|O_TRUNC|O_WRONLY|O_CLOEXEC, 0666);
if (fd < 0) {
_warn("_mcleanup: %s", outname);
return;
}
#ifdef DEBUG
log = _open("gmon.log", O_CREAT|O_TRUNC|O_WRONLY|O_CLOEXEC, 0664);
if (log < 0) {
_warn("_mcleanup: gmon.log");
return;
}
len = sprintf(buf, "[mcleanup1] kcount 0x%p ssiz %lu\n",
p->kcount, p->kcountsize);
_write(log, buf, len);
#endif
hdr = (struct gmonhdr *)&gmonhdr;
bzero(hdr, sizeof(*hdr));
hdr->lpc = p->lowpc;
hdr->hpc = p->highpc;
hdr->ncnt = p->kcountsize + sizeof(gmonhdr);
hdr->version = GMONVERSION;
hdr->profrate = clockinfo.profhz;
_write(fd, (char *)hdr, sizeof *hdr);
_write(fd, p->kcount, p->kcountsize);
endfrom = p->fromssize / sizeof(*p->froms);
for (fromindex = 0; fromindex < endfrom; fromindex++) {
if (p->froms[fromindex] == 0)
continue;
frompc = p->lowpc;
frompc += fromindex * p->hashfraction * sizeof(*p->froms);
for (toindex = p->froms[fromindex]; toindex != 0;
toindex = p->tos[toindex].link) {
#ifdef DEBUG
len = sprintf(buf,
"[mcleanup2] frompc 0x%lx selfpc 0x%lx count %lu\n" ,
frompc, p->tos[toindex].selfpc,
p->tos[toindex].count);
_write(log, buf, len);
#endif
rawarc.raw_frompc = frompc;
rawarc.raw_selfpc = p->tos[toindex].selfpc;
rawarc.raw_count = p->tos[toindex].count;
_write(fd, &rawarc, sizeof rawarc);
}
}
_close(fd);
}
/*
* Control profiling
* profiling is what mcount checks to see if
* all the data structures are ready.
*/
void
moncontrol(int mode)
{
struct gmonparam *p = &_gmonparam;
if (mode) {
/* start */
profil((char *)p->kcount, p->kcountsize, p->lowpc, s_scale);
p->state = GMON_PROF_ON;
} else {
/* stop */
profil((char *)0, 0, 0, 0);
p->state = GMON_PROF_OFF;
}
}
/*
* discover the tick frequency of the machine
* if something goes wrong, we return 0, an impossible hertz.
*/
static int
hertz(void)
{
struct itimerval tim;
tim.it_interval.tv_sec = 0;
tim.it_interval.tv_usec = 1;
tim.it_value.tv_sec = 0;
tim.it_value.tv_usec = 0;
setitimer(ITIMER_REAL, &tim, 0);
setitimer(ITIMER_REAL, 0, &tim);
if (tim.it_interval.tv_usec < 2)
return(0);
return (1000000 / tim.it_interval.tv_usec);
}