gcc/libgomp/config/posix/proc.c
Thomas Schwinge f1f3453e11 libgomp: Now known as the GNU Offloading and Multi Processing Runtime Library.
libgomp/
	* configure.ac: Rename libgomp from "GNU OpenMP Runtime Library"
	to "GNU Offloading and Multi Processing Runtime Library".  Change
	all users.
	* configure: Regenerate.
	* libgomp.texi: Update.
	gcc/
	* doc/install.texi: Update for libgomp being renamed from "GNU
	OpenMP Runtime Library" to "GNU Offloading and Multi Processing
	Runtime Library".
	* doc/sourcebuild.texi: Likewise.
	gcc/fortran/
	* gfortran.texi: Update for libgomp being renamed from "GNU OpenMP
	Runtime Library" to "GNU Offloading and Multi Processing Runtime
	Library".
	* intrinsic.texi: Likewise.
	libstdc++-v3/
	* doc/xml/manual/parallel_mode.xml: Update for libgomp being
	renamed from "GNU OpenMP Runtime Library" to "GNU Offloading and
	Multi Processing Runtime Library".

Co-Authored-By: David Malcolm <dmalcolm@redhat.com>
Co-Authored-By: Julian Brown <julian@codesourcery.com>

From-SVN: r219425
2015-01-10 20:10:37 +01:00

103 lines
2.9 KiB
C

/* Copyright (C) 2005-2015 Free Software Foundation, Inc.
Contributed by Richard Henderson <rth@redhat.com>.
This file is part of the GNU Offloading and Multi Processing Library
(libgomp).
Libgomp is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
Libgomp 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 General Public License for
more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
/* This file contains system specific routines related to counting
online processors and dynamic load balancing. It is expected that
a system may well want to write special versions of each of these.
The following implementation uses a mix of POSIX and BSD routines. */
#include "libgomp.h"
#include <unistd.h>
#include <stdlib.h>
#ifdef HAVE_GETLOADAVG
# ifdef HAVE_SYS_LOADAVG_H
# include <sys/loadavg.h>
# endif
#endif
/* At startup, determine the default number of threads. It would seem
this should be related to the number of cpus online. */
void
gomp_init_num_threads (void)
{
#ifdef _SC_NPROCESSORS_ONLN
gomp_global_icv.nthreads_var = sysconf (_SC_NPROCESSORS_ONLN);
#endif
}
/* When OMP_DYNAMIC is set, at thread launch determine the number of
threads we should spawn for this team. */
/* ??? I have no idea what best practice for this is. Surely some
function of the number of processors that are *still* online and
the load average. Here I use the number of processors online
minus the 15 minute load average. */
unsigned
gomp_dynamic_max_threads (void)
{
unsigned n_onln, loadavg;
unsigned nthreads_var = gomp_icv (false)->nthreads_var;
#ifdef _SC_NPROCESSORS_ONLN
n_onln = sysconf (_SC_NPROCESSORS_ONLN);
if (n_onln > nthreads_var)
n_onln = nthreads_var;
#else
n_onln = nthreads_var;
#endif
loadavg = 0;
#ifdef HAVE_GETLOADAVG
{
double dloadavg[3];
if (getloadavg (dloadavg, 3) == 3)
{
/* Add 0.1 to get a kind of biased rounding. */
loadavg = dloadavg[2] + 0.1;
}
}
#endif
if (loadavg >= n_onln)
return 1;
else
return n_onln - loadavg;
}
int
omp_get_num_procs (void)
{
#ifdef _SC_NPROCESSORS_ONLN
return sysconf (_SC_NPROCESSORS_ONLN);
#else
return gomp_icv (false)->nthreads_var;
#endif
}
ialias (omp_get_num_procs)