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authorRoland McGrath <roland@gnu.org>1995-09-26 20:59:38 +0000
committerRoland McGrath <roland@gnu.org>1995-09-26 20:59:38 +0000
commit11c981a96d93feccba7cfb717f72db5d32a83f52 (patch)
treec9e22c5e94375dff6d4334b552dd0dbc1d169efb
parente11c394911f221a862cbdec8aab4a363394711c6 (diff)
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Tue Sep 26 16:50:17 1995 Roland McGrath <roland@churchy.gnu.ai.mit.edu>
	* gmon: New directory of profiling code, incorporated from
	4.4BSD-Lite and modified.
	* sysdeps/i386/machine-gmon.h: New file.
	* sysdeps/stub/machine-gmon.h: New file.
	* sysdeps/mach/hurd/profil.c: New file.
	* sysdeps/stub/profil.c: New file.
	* sysdeps/unix/bsd/profil.S: New file.
	* Makefile (subdirs): Add gmon.
	* csu/gmon-start.c: New file.
	* csu/Makefile (extra-objs): Add gmon-start.o,
	g$(start-installed-name).
	(install-lib, omit-deps): Add g$(start-installed-name).
	($(objpfx)g$(start-installed-name)): New target.
-rw-r--r--ChangeLog16
-rw-r--r--Makefile2
-rw-r--r--csu/Makefile25
-rw-r--r--csu/gmon-start.c47
-rw-r--r--gmon/Makefile28
-rw-r--r--gmon/gmon.c232
-rw-r--r--gmon/mcount.c178
-rw-r--r--gmon/sys/gmon.h159
-rw-r--r--sys/gmon.h1
-rw-r--r--sysdeps/i386/machine-gmon.h29
-rw-r--r--sysdeps/mach/hurd/profil.c164
-rw-r--r--sysdeps/stub/machine-gmon.h28
-rw-r--r--sysdeps/stub/profil.c40
-rw-r--r--sysdeps/unix/bsd/profil.S23
14 files changed, 963 insertions, 9 deletions
diff --git a/ChangeLog b/ChangeLog
index 427ec01b97..bf85dbe212 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,19 @@
+Tue Sep 26 16:50:17 1995  Roland McGrath  <roland@churchy.gnu.ai.mit.edu>
+
+	* gmon: New directory of profiling code, incorporated from
+	4.4BSD-Lite and modified.
+	* sysdeps/i386/machine-gmon.h: New file.
+	* sysdeps/stub/machine-gmon.h: New file.
+	* sysdeps/mach/hurd/profil.c: New file.
+	* sysdeps/stub/profil.c: New file.
+	* sysdeps/unix/bsd/profil.S: New file.
+	* Makefile (subdirs): Add gmon.
+	* csu/gmon-start.c: New file.
+	* csu/Makefile (extra-objs): Add gmon-start.o,
+	g$(start-installed-name).
+	(install-lib, omit-deps): Add g$(start-installed-name).
+	($(objpfx)g$(start-installed-name)): New target.
+
 Fri Sep 22 14:24:25 1995  Roland McGrath  <roland@churchy.gnu.ai.mit.edu>
 
 	* sysdeps/mach/hurd/Makefile: Elide sunrpc from $(subdirs) for the
diff --git a/Makefile b/Makefile
index 56601e5282..64cdebfeec 100644
--- a/Makefile
+++ b/Makefile
@@ -53,7 +53,7 @@ endif
 # These are the subdirectories containing the library source.
 subdirs := csu assert ctype locale math setjmp signal stdio stdlib	\
 	   malloc string time dirent grp pwd posix io termios resource	\
-	   misc socket sysvipc gnulib $(wildcard crypt) manual		\
+	   misc socket sysvipc gmon gnulib $(wildcard crypt) manual	\
 	   $(sysdep-subdirs) elf
 export subdirs := $(subdirs)	# Benign, useless in GNU make before 3.63.
 
diff --git a/csu/Makefile b/csu/Makefile
index 8f97624240..4fddba2f3a 100644
--- a/csu/Makefile
+++ b/csu/Makefile
@@ -20,18 +20,21 @@
 
 # This directory contains the C startup code (that which calls main).  This
 # consists of the startfile, built from start.c and installed as crt0.o
-# (traditionally) or crt1.o (for ELF); and some initialization code which
-# is in the C library itself.  In ELF we also install crti.o and crtn.o,
-# special "initializer" and "finalizer" files in used in the link to make
-# the .init and .fini sections work right; both these files are built (in
-# an arcane manner) from initfini.c.
+# (traditionally) or crt1.o (for ELF).  In ELF we also install crti.o and
+# crtn.o, special "initializer" and "finalizer" files in used in the link
+# to make the .init and .fini sections work right; both these files are
+# built (in an arcane manner) from initfini.c.
 
 subdir := csu
 
 csu-dummies = $(filter-out $(start-installed-name),crt1.o Mcrt1.o)
-extra-objs = start.o $(start-installed-name) $(csu-dummies)
-omit-deps = $(patsubst %.o,%,$(start-installed-name) $(csu-dummies))
-install-lib = $(start-installed-name) $(csu-dummies)
+extra-objs = start.o gmon-start.o \
+	     $(start-installed-name) g$(start-installed-name) \
+	     $(csu-dummies)
+omit-deps = $(patsubst %.o,%,$(start-installed-name) g$(start-installed-name) \
+		             $(csu-dummies))
+install-lib = $(start-installed-name) g$(start-installed-name) \
+	      $(csu-dummies)
 distribute = initfini.c
 
 all: # Make this the default target; it will be defined in Rules.
@@ -95,6 +98,12 @@ $(objpfx)$(start-installed-name): $(objpfx)start.o
 	ln $< $@
 endif
 
+# The profiling startfile is made by linking together the normal
+# startfile with gmon-start.o, which defines a constructor function
+# to turn on profiling code at startup.
+$(objpfx)g$(start-installed-name): $(objpfx)start.o $(objpfx)gmon-start.o
+	$(CC) -nostdlib -nostartfiles -r -o $@ $^
+
 # These extra files are sometimes expected by system standard linking
 # procedures, but we have nothing for them to do.  So compile empty files.
 $(addprefix $(objpfx),$(filter-out $(start-installed-name),$(csu-dummies))):
diff --git a/csu/gmon-start.c b/csu/gmon-start.c
new file mode 100644
index 0000000000..c9d51b113b
--- /dev/null
+++ b/csu/gmon-start.c
@@ -0,0 +1,47 @@
+/* Code to enable profiling at program startup.
+Copyright (C) 1995 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <sys/types.h>
+#include <sys/gmon.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+/* Beginning and end of our code segment.  */
+extern void _start (), etext ();
+
+/* These functions are defined in gmon/gmon.c;
+   they do all the work of setting up and cleaning up profiling.  */
+extern void monstartup (u_long, u_long);
+extern void _mcleanup (void);
+
+/* This function gets called at startup by the normal constructor
+   mechanism.  We link this file together with start.o to produce gcrt1.o,
+   so this constructor will be first in the list.  */
+static void gmon_start (void) __attribute__ ((constructor));
+static void
+gmon_start (void)
+{
+  /* Start keeping profiling records.  */
+  monstartup ((u_long) &_start, (u_long) &etext);
+
+  /* Call _mcleanup before exitting; it will write out gmon.out from the
+     collected data.  */
+  atexit (&_mcleanup);
+}
+
diff --git a/gmon/Makefile b/gmon/Makefile
new file mode 100644
index 0000000000..3bd4201b72
--- /dev/null
+++ b/gmon/Makefile
@@ -0,0 +1,28 @@
+# Copyright (C) 1995 Free Software Foundation, Inc.
+# This file is part of the GNU C Library.
+
+# The GNU C Library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Library General Public License as
+# published by the Free Software Foundation; either version 2 of the
+# License, or (at your option) any later version.
+
+# The GNU C Library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Library General Public License for more details.
+
+# You should have received a copy of the GNU Library General Public
+# License along with the GNU C Library; see the file COPYING.LIB.  If
+# not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+# Cambridge, MA 02139, USA.
+
+#
+#	Sub-makefile for gmon portion of the library.
+#
+subdir	:= gmon
+
+headers	:= sys/gmon.h machine-gmon.h
+
+routines := gmon mcount profil
+
+include ../Rules
diff --git a/gmon/gmon.c b/gmon/gmon.c
new file mode 100644
index 0000000000..df528e259f
--- /dev/null
+++ b/gmon/gmon.c
@@ -0,0 +1,232 @@
+/*-
+ * 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. 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(lint) && defined(LIBC_SCCS)
+static char sccsid[] = "@(#)gmon.c	8.1 (Berkeley) 6/4/93";
+#endif
+
+#include <sys/param.h>
+#include <sys/time.h>
+#include <sys/gmon.h>
+
+#include <stdio.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+struct gmonparam _gmonparam = { GMON_PROF_OFF };
+
+static int	s_scale;
+/* see profil(2) where this is describe (incorrectly) */
+#define		SCALE_1_TO_1	0x10000L
+
+#define ERR(s) write(2, s, sizeof(s) - 1)
+
+void	moncontrol __P((int));
+static int hertz __P((void));
+
+void
+monstartup(lowpc, highpc)
+	u_long lowpc;
+	u_long highpc;
+{
+	register 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 = malloc (p->kcountsize + p->fromssize + p->tossize);
+	if (! cp) {
+		ERR("monstartup: out of memory\n");
+		return;
+	}
+	bzero(cp, p->kcountsize + p->fromssize + p->tossize);
+	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;
+	if (p->kcountsize < o) {
+#ifndef hp300
+		s_scale = ((float)p->kcountsize / o ) * SCALE_1_TO_1;
+#else /* avoid floating point */
+		int quot = o / p->kcountsize;
+		
+		if (quot >= 0x10000)
+			s_scale = 1;
+		else if (quot >= 0x100)
+			s_scale = 0x10000 / quot;
+		else if (o >= 0x800000)
+			s_scale = 0x1000000 / (o / (p->kcountsize >> 8));
+		else
+			s_scale = 0x1000000 / ((o << 8) / p->kcountsize);
+#endif
+	} else
+		s_scale = SCALE_1_TO_1;
+
+	moncontrol(1);
+}
+
+void
+_mcleanup()
+{
+	int fd;
+	int fromindex;
+	int endfrom;
+	u_long frompc;
+	int toindex;
+	struct rawarc rawarc;
+	struct gmonparam *p = &_gmonparam;
+	struct gmonhdr gmonhdr, *hdr;
+#ifdef DEBUG
+	int log, len;
+	char buf[200];
+#endif
+
+	if (p->state == GMON_PROF_ERROR)
+		ERR("_mcleanup: tos overflow\n");
+
+	moncontrol(0);
+	fd = open("gmon.out", O_CREAT|O_TRUNC|O_WRONLY, 0666);
+	if (fd < 0) {
+		perror("mcount: gmon.out");
+		return;
+	}
+#ifdef DEBUG
+	log = open("gmon.log", O_CREAT|O_TRUNC|O_WRONLY, 0664);
+	if (log < 0) {
+		perror("mcount: gmon.log");
+		return;
+	}
+	len = sprintf(buf, "[mcleanup1] kcount 0x%x ssiz %d\n",
+	    p->kcount, p->kcountsize);
+	write(log, buf, len);
+#endif
+	hdr = (struct gmonhdr *)&gmonhdr;
+	hdr->lpc = p->lowpc;
+	hdr->hpc = p->highpc;
+	hdr->ncnt = p->kcountsize + sizeof(gmonhdr);
+	hdr->version = GMONVERSION;
+	hdr->profrate = hertz();
+	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%x selfpc 0x%x count %d\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(mode)
+	int mode;
+{
+	struct gmonparam *p = &_gmonparam;
+
+	if (mode) {
+		/* start */
+		profil((char *)p->kcount, p->kcountsize, (int)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()
+{
+	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);
+}
+
+
diff --git a/gmon/mcount.c b/gmon/mcount.c
new file mode 100644
index 0000000000..523217d1d2
--- /dev/null
+++ b/gmon/mcount.c
@@ -0,0 +1,178 @@
+/*-
+ * 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. 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(lint) && !defined(KERNEL) && defined(LIBC_SCCS)
+static char sccsid[] = "@(#)mcount.c	8.1 (Berkeley) 6/4/93";
+#endif
+
+#include <sys/param.h>
+#include <sys/gmon.h>
+
+/*
+ * mcount is called on entry to each function compiled with the profiling
+ * switch set.  _mcount(), which is declared in a machine-dependent way
+ * with _MCOUNT_DECL, does the actual work and is either inlined into a
+ * C routine or called by an assembly stub.  In any case, this magic is
+ * taken care of by the MCOUNT definition in <machine/profile.h>.
+ *
+ * _mcount updates data structures that represent traversals of the
+ * program's call graph edges.  frompc and selfpc are the return
+ * address and function address that represents the given call graph edge.
+ * 
+ * Note: the original BSD code used the same variable (frompcindex) for
+ * both frompcindex and frompc.  Any reasonable, modern compiler will
+ * perform this optimization.
+ */
+_MCOUNT_DECL(frompc, selfpc)	/* _mcount; may be static, inline, etc */
+	register u_long frompc, selfpc;
+{
+	register u_short *frompcindex;
+	register struct tostruct *top, *prevtop;
+	register struct gmonparam *p;
+	register long toindex;
+#ifdef KERNEL
+	register int s;
+#endif
+
+	p = &_gmonparam;
+	/*
+	 * check that we are profiling
+	 * and that we aren't recursively invoked.
+	 */
+	if (p->state != GMON_PROF_ON)
+		return;
+#ifdef KERNEL
+	MCOUNT_ENTER;
+#else
+	p->state = GMON_PROF_BUSY;
+#endif
+	/*
+	 * check that frompcindex is a reasonable pc value.
+	 * for example:	signal catchers get called from the stack,
+	 *		not from text space.  too bad.
+	 */
+	frompc -= p->lowpc;
+	if (frompc > p->textsize)
+		goto done;
+
+	frompcindex = &p->froms[frompc / (p->hashfraction * sizeof(*p->froms))];
+	toindex = *frompcindex;
+	if (toindex == 0) {
+		/*
+		 *	first time traversing this arc
+		 */
+		toindex = ++p->tos[0].link;
+		if (toindex >= p->tolimit)
+			/* halt further profiling */
+			goto overflow;
+
+		*frompcindex = toindex;
+		top = &p->tos[toindex];
+		top->selfpc = selfpc;
+		top->count = 1;
+		top->link = 0;
+		goto done;
+	}
+	top = &p->tos[toindex];
+	if (top->selfpc == selfpc) {
+		/*
+		 * arc at front of chain; usual case.
+		 */
+		top->count++;
+		goto done;
+	}
+	/*
+	 * have to go looking down chain for it.
+	 * top points to what we are looking at,
+	 * prevtop points to previous top.
+	 * we know it is not at the head of the chain.
+	 */
+	for (; /* goto done */; ) {
+		if (top->link == 0) {
+			/*
+			 * top is end of the chain and none of the chain
+			 * had top->selfpc == selfpc.
+			 * so we allocate a new tostruct
+			 * and link it to the head of the chain.
+			 */
+			toindex = ++p->tos[0].link;
+			if (toindex >= p->tolimit)
+				goto overflow;
+
+			top = &p->tos[toindex];
+			top->selfpc = selfpc;
+			top->count = 1;
+			top->link = *frompcindex;
+			*frompcindex = toindex;
+			goto done;
+		}
+		/*
+		 * otherwise, check the next arc on the chain.
+		 */
+		prevtop = top;
+		top = &p->tos[top->link];
+		if (top->selfpc == selfpc) {
+			/*
+			 * there it is.
+			 * increment its count
+			 * move it to the head of the chain.
+			 */
+			top->count++;
+			toindex = prevtop->link;
+			prevtop->link = top->link;
+			top->link = *frompcindex;
+			*frompcindex = toindex;
+			goto done;
+		}
+		
+	}
+done:
+#ifdef KERNEL
+	MCOUNT_EXIT;
+#else
+	p->state = GMON_PROF_ON;
+#endif
+	return;
+overflow:
+	p->state = GMON_PROF_ERROR;
+#ifdef KERNEL
+	MCOUNT_EXIT;
+#endif
+	return;
+}
+
+/*
+ * Actual definition of mcount function.  Defined in <machine/profile.h>,
+ * which is included by <sys/gmon.h>.
+ */
+MCOUNT
diff --git a/gmon/sys/gmon.h b/gmon/sys/gmon.h
new file mode 100644
index 0000000000..6a682d0b10
--- /dev/null
+++ b/gmon/sys/gmon.h
@@ -0,0 +1,159 @@
+/*-
+ * Copyright (c) 1982, 1986, 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. 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.
+ *
+ *	@(#)gmon.h	8.2 (Berkeley) 1/4/94
+ */
+
+#ifndef _SYS_GMON_H_
+#define _SYS_GMON_H_
+
+#include <machine-gmon.h>
+
+/*
+ * Structure prepended to gmon.out profiling data file.
+ */
+struct gmonhdr {
+	u_long	lpc;		/* base pc address of sample buffer */
+	u_long	hpc;		/* max pc address of sampled buffer */
+	int	ncnt;		/* size of sample buffer (plus this header) */
+	int	version;	/* version number */
+	int	profrate;	/* profiling clock rate */
+	int	spare[3];	/* reserved */
+};
+#define GMONVERSION	0x00051879
+
+/*
+ * histogram counters are unsigned shorts (according to the kernel).
+ */
+#define	HISTCOUNTER	unsigned short
+
+/*
+ * fraction of text space to allocate for histogram counters here, 1/2
+ */
+#define	HISTFRACTION	2
+
+/*
+ * Fraction of text space to allocate for from hash buckets.
+ * The value of HASHFRACTION is based on the minimum number of bytes
+ * of separation between two subroutine call points in the object code.
+ * Given MIN_SUBR_SEPARATION bytes of separation the value of
+ * HASHFRACTION is calculated as:
+ *
+ *	HASHFRACTION = MIN_SUBR_SEPARATION / (2 * sizeof(short) - 1);
+ *
+ * For example, on the VAX, the shortest two call sequence is:
+ *
+ *	calls	$0,(r0)
+ *	calls	$0,(r0)
+ *
+ * which is separated by only three bytes, thus HASHFRACTION is 
+ * calculated as:
+ *
+ *	HASHFRACTION = 3 / (2 * 2 - 1) = 1
+ *
+ * Note that the division above rounds down, thus if MIN_SUBR_FRACTION
+ * is less than three, this algorithm will not work!
+ *
+ * In practice, however, call instructions are rarely at a minimal 
+ * distance.  Hence, we will define HASHFRACTION to be 2 across all
+ * architectures.  This saves a reasonable amount of space for 
+ * profiling data structures without (in practice) sacrificing
+ * any granularity.
+ */
+#define	HASHFRACTION	2
+
+/*
+ * percent of text space to allocate for tostructs with a minimum.
+ */
+#define ARCDENSITY	2
+#define MINARCS		50
+#define MAXARCS		((1 << (8 * sizeof(HISTCOUNTER))) - 2)
+
+struct tostruct {
+	u_long	selfpc;
+	long	count;
+	u_short	link;
+	u_short pad;
+};
+
+/*
+ * a raw arc, with pointers to the calling site and 
+ * the called site and a count.
+ */
+struct rawarc {
+	u_long	raw_frompc;
+	u_long	raw_selfpc;
+	long	raw_count;
+};
+
+/*
+ * general rounding functions.
+ */
+#define ROUNDDOWN(x,y)	(((x)/(y))*(y))
+#define ROUNDUP(x,y)	((((x)+(y)-1)/(y))*(y))
+
+/*
+ * The profiling data structures are housed in this structure.
+ */
+struct gmonparam {
+	int		state;
+	u_short		*kcount;
+	u_long		kcountsize;
+	u_short		*froms;
+	u_long		fromssize;
+	struct tostruct	*tos;
+	u_long		tossize;
+	long		tolimit;
+	u_long		lowpc;
+	u_long		highpc;
+	u_long		textsize;
+	u_long		hashfraction;
+};
+extern struct gmonparam _gmonparam;
+
+/*
+ * Possible states of profiling.
+ */
+#define	GMON_PROF_ON	0
+#define	GMON_PROF_BUSY	1
+#define	GMON_PROF_ERROR	2
+#define	GMON_PROF_OFF	3
+
+/*
+ * Sysctl definitions for extracting profiling information from the kernel.
+ */
+#define	GPROF_STATE	0	/* int: profiling enabling variable */
+#define	GPROF_COUNT	1	/* struct: profile tick count buffer */
+#define	GPROF_FROMS	2	/* struct: from location hash bucket */
+#define	GPROF_TOS	3	/* struct: destination/count structure */
+#define	GPROF_GMONPARAM	4	/* struct: profiling parameters (see above) */
+#endif /* !_SYS_GMON_H_ */
diff --git a/sys/gmon.h b/sys/gmon.h
new file mode 100644
index 0000000000..987589fcfe
--- /dev/null
+++ b/sys/gmon.h
@@ -0,0 +1 @@
+#include <gmon/sys/gmon.h>
diff --git a/sysdeps/i386/machine-gmon.h b/sysdeps/i386/machine-gmon.h
new file mode 100644
index 0000000000..4128390b8b
--- /dev/null
+++ b/sysdeps/i386/machine-gmon.h
@@ -0,0 +1,29 @@
+/* Machine-specific calling sequence for `mcount' profiling function.  i386
+Copyright (C) 1995 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#define _MCOUNT_DECL static inline void _mcount
+
+/* Call _mcount with our the return PC for our caller,
+   and the return PC our caller will return to.  */
+#define MCOUNT								      \
+void mcount (u_long arg)						      \
+{									      \
+  _mcount (((u_long *) (&arg)[-2])[-1],					      \
+	   (&arg)[-1]);							      \
+}
diff --git a/sysdeps/mach/hurd/profil.c b/sysdeps/mach/hurd/profil.c
new file mode 100644
index 0000000000..4032219a9e
--- /dev/null
+++ b/sysdeps/mach/hurd/profil.c
@@ -0,0 +1,164 @@
+/* Low-level statistical profiling support function.  Mach/Hurd version.
+Copyright (C) 1995 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <sys/types.h>
+#include <unistd.h>
+#include <errno.h>
+#include <hurd.h>
+#include <mach/mach4.h>
+#include <mach/pc_sample.h>
+#include <cthreads.h>
+#include <assert.h>
+
+static thread_t profile_thread = MACH_PORT_NULL;
+static u_short *samples;
+static size_t maxsamples;
+static size_t pc_offset;
+static size_t sample_scale;
+static sampled_pc_seqno_t seqno;
+static struct mutex lock = MUTEX_INITIALIZER;
+
+/* Enable statistical profiling, writing samples of the PC into at most
+   SIZE bytes of SAMPLE_BUFFER; every processor clock tick while profiling
+   is enabled, the system examines the user PC and increments
+   SAMPLE_BUFFER[((PC - OFFSET) / 2) * SCALE / 65536].  If SCALE is zero,
+   disable profiling.  Returns zero on success, -1 on error.  */
+
+static error_t
+update_waiter (u_short *sample_buffer, size_t size, size_t offset, u_int scale)
+{
+  error_t err;
+
+  if (profile_thread == MACH_PORT_NULL)
+    {
+      /* Set up the profiling collector thread.  */
+      static void profile_waiter (void);
+      err = __thread_create (__mach_task_self (), &profile_thread);
+      if (! err)
+	err = __mach_setup_thread (__mach_task_self (), profile_thread,
+				   &profile_waiter, NULL, NULL);
+    }
+  else
+    err = 0;
+
+  if (! err)
+    {
+      if (sample_scale == 0)
+	err = __thread_resume (profile_thread);
+      if (! err)
+	{
+	  samples = sample_buffer;
+	  maxsamples = size / sizeof *sample_buffer;
+	  pc_offset = offset;
+	  sample_scale = scale;
+	}
+    }
+
+  return err;
+}
+
+int
+profil (u_short *sample_buffer, size_t size, size_t offset, u_int scale)
+{
+  error_t err;
+
+  __mutex_lock (&lock);
+
+  if (scale == 0)
+    {
+      /* Disable profiling.  */
+      int count;
+      __thread_suspend (profile_thread);
+      err = __task_disable_pc_sampling (__mach_task_self (), &count);
+      sample_scale = 0;
+      seqno = 0;
+    }
+  else
+    err = update_waiter (sample_buffer, size, offset, scale);
+
+  __mutex_unlock (&lock);
+
+  return err ? __hurd_fail (err) : 0;
+}
+
+static void
+profile_waiter (void)
+{
+  sampled_pc_t pc_samples[512];
+  mach_msg_type_number_t nsamples = 512, i;
+  mach_port_t rcv = __mach_reply_port ();
+  mach_msg_header_t msg;
+  const mach_msg_timeout_t timeout = 17; /* ??? XXX */
+  error_t err;
+
+  while (1)
+    {
+      __mutex_lock (&lock);
+
+      err = __task_get_sampled_pcs (__mach_task_self (), &seqno,
+				    pc_samples, &nsamples);
+      assert_perror (err);
+
+      for (i = 0; i < nsamples; ++i)
+	{
+	  size_t idx = (((pc_samples[i].pc - pc_offset) / 2) *
+			sample_scale / 65536);
+	  if (idx < maxsamples)
+	    ++samples[idx];
+	}
+
+      __vm_deallocate (__mach_task_self (),
+		       (vm_address_t) pc_samples,
+		       nsamples * sizeof *pc_samples);
+
+      __mutex_unlock (&lock);
+
+      __mach_msg (&msg, MACH_RCV_MSG|MACH_RCV_TIMEOUT, 0, sizeof msg,
+		  rcv, timeout, MACH_PORT_NULL);
+    }
+}
+
+data_set_element (_hurd_fork_locks, lock);
+
+static void
+fork_profil (void)
+{
+  u_short *sb;
+  size_t n, o, ss;
+  error_t err;
+
+  if (profile_thread != MACH_PORT_NULL)
+    {
+      __mach_port_deallocate (__mach_task_self (), profile_thread);
+      profile_thread = MACH_PORT_NULL;
+    }
+
+  sb = samples;
+  samples = NULL;
+  n = maxsamples;
+  maxsamples = 0;
+  o = pc_offset;
+  pc_offset = 0;
+  ss = sample_scale;
+  sample_scale = 0;
+
+  err = update_waiter (sb, n * sizeof *sb, o, ss);
+  assert_perror (err);
+}
+text_set_element (_hurd_fork_child_hook, fork_profil);
diff --git a/sysdeps/stub/machine-gmon.h b/sysdeps/stub/machine-gmon.h
new file mode 100644
index 0000000000..a6edbc062d
--- /dev/null
+++ b/sysdeps/stub/machine-gmon.h
@@ -0,0 +1,28 @@
+/* Machine-specific calling sequence for `mcount' profiling function.  Stub
+Copyright (C) 1995 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#define _MCOUNT_DECL static inline void _mcount
+
+/* Call _mcount with our the return PC for our caller,
+   and the return PC our caller will return to.  */
+#define MCOUNT								      \
+void mcount (u_long arg)						      \
+{									      \
+  _mcount (caller return PC, my return PC);				      \
+}
diff --git a/sysdeps/stub/profil.c b/sysdeps/stub/profil.c
new file mode 100644
index 0000000000..ab8e1d4ed6
--- /dev/null
+++ b/sysdeps/stub/profil.c
@@ -0,0 +1,40 @@
+/* Low-level statistical profiling support function.  Stub version.
+Copyright (C) 1995 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <sys/types.h>
+#include <unistd.h>
+#include <errno.h>
+
+/* Enable statistical profiling, writing samples of the PC into at most
+   SIZE bytes of SAMPLE_BUFFER; every processor clock tick while profiling
+   is enabled, the system examines the user PC and increments
+   SAMPLE_BUFFER[((PC - OFFSET) / 2) * SCALE / 65536].  If SCALE is zero,
+   disable profiling.  Returns zero on success, -1 on error.  */
+
+int
+profil (u_short *sample_buffer, size_t size, size_t offset, u_int scale)
+{
+  if (scale == 0)
+    /* Disable profiling.  */
+    return 0;
+
+  errno = ENOSYS;
+  return -1;
+}
+stub_warning (profil)
diff --git a/sysdeps/unix/bsd/profil.S b/sysdeps/unix/bsd/profil.S
new file mode 100644
index 0000000000..22429bd46b
--- /dev/null
+++ b/sysdeps/unix/bsd/profil.S
@@ -0,0 +1,23 @@
+/* Low-level statistical profiling support function.  Unix syscall version.
+Copyright (C) 1995 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include <sysdep.h>
+
+SYSCALL (profil, 4)
+	ret