1 files changed, 65 insertions, 0 deletions
diff --git a/libgomp/config/linux/wait.h b/libgomp/config/linux/wait.h
new file mode 100644
index 000000000..0e8abf111
--- /dev/null
+++ b/libgomp/config/linux/wait.h
@@ -0,0 +1,65 @@
+/* Copyright (C) 2008, 2009, 2011 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 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 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 */