--- /dev/null
+/* Copyright (C) 2005, 2006, 2008 Free Software Foundation, Inc.
+ Contributed by Richard Henderson <rth@redhat.com>.
+
+ This file is part of the GNU OpenMP Library (libgomp).
+
+ Libgomp is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, 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 Lesser General Public License for
+ more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with libgomp; see the file COPYING.LIB. If not, write to the
+ Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+ MA 02110-1301, USA. */
+
+/* As a special exception, if you link this library with other files, some
+ of which are compiled with GCC, to produce an executable, this library
+ does not by itself cause the resulting executable to be covered by the
+ GNU General Public License. This exception does not however invalidate
+ any other reasons why the executable file might be covered by the GNU
+ General Public License. */
+
+/* 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
+#ifdef HAVE_SYS_SYSCTL_H
+# include <sys/sysctl.h>
+#endif
+
+static int
+get_num_procs (void)
+{
+#ifdef _SC_NPROCESSORS_ONLN
+ return sysconf (_SC_NPROCESSORS_ONLN);
+#elif defined HW_NCPU
+ int ncpus = 1;
+ size_t len = sizeof(ncpus);
+ sysctl((int[2]) {CTL_HW, HW_NCPU}, 2, &ncpus, &len, NULL, 0);
+ return ncpus;
+#else
+ return 0;
+#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)
+{
+ int ncpus = get_num_procs ();
+
+ if (ncpus > 0)
+ gomp_global_icv.nthreads_var = ncpus;
+}
+
+/* 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;
+
+ n_onln = get_num_procs ();
+ if (!n_onln || n_onln > nthreads_var)
+ n_onln = nthreads_var;
+
+ 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)
+{
+ int ncpus = get_num_procs ();
+ if (ncpus <= 0)
+ ncpus = gomp_icv (false)->nthreads_var;
+ return ncpus;
+}
+
+ialias (omp_get_num_procs)
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