1 files changed, 68 insertions, 0 deletions
diff --git a/libgomp/config/linux/wait.h b/libgomp/config/linux/wait.h
new file mode 100644
index 00000000000..21f0ab8756c
--- /dev/null
+++ b/libgomp/config/linux/wait.h
@@ -0,0 +1,68 @@
+/* Copyright (C) 2008 Free Software Foundation, Inc.
+   Contributed by Jakub Jelinek <jakub@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 is a Linux specific implementation of a mutex synchronization
+   mechanism for libgomp.  This type is private to the library.  This
+   implementation uses atomic instructions and the futex syscall.  */
+
+#ifndef GOMP_WAIT_H
+#define GOMP_WAIT_H 1
+
+#include "libgomp.h"
+#include <errno.h>
+
+#define FUTEX_WAIT	0
+#define FUTEX_WAKE	1
+#define FUTEX_PRIVATE_FLAG	128L
+
+#ifdef HAVE_ATTRIBUTE_VISIBILITY
+# pragma GCC visibility push(hidden)
+#endif
+
+extern long int gomp_futex_wait, gomp_futex_wake;
+
+#include "futex.h"
+
+static inline void do_wait (int *addr, int val)
+{
+  unsigned long long i, count = gomp_spin_count_var;
+
+  if (__builtin_expect (gomp_managed_threads > gomp_available_cpus, 0))
+    count = gomp_throttled_spin_count_var;
+  for (i = 0; i < count; i++)
+    if (__builtin_expect (*addr != val, 0))
+      return;
+    else
+      cpu_relax ();
+  futex_wait (addr, val);
+}
+
+#ifdef HAVE_ATTRIBUTE_VISIBILITY
+# pragma GCC visibility pop
+#endif
+
+#endif /* GOMP_WAIT_H */