1 files changed, 82 insertions, 0 deletions
diff --git a/libitm/config/linux/futex.cc b/libitm/config/linux/futex.cc
new file mode 100644
index 00000000000..45c9db62dbb
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+++ b/libitm/config/linux/futex.cc
@@ -0,0 +1,82 @@
+/* Copyright (C) 2008, 2009, 2011 Free Software Foundation, Inc.
+   Contributed by Richard Henderson <rth@redhat.com>.
+
+   This file is part of the GNU Transactional Memory Library (libitm).
+
+   Libitm 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 of the License, or
+   (at your option) any later version.
+
+   Libitm 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/>.  */
+
+/* Provide access to the futex system call.  */
+
+#include "libitm_i.h"
+#include "futex.h"
+#include <errno.h>
+
+namespace GTM HIDDEN {
+
+#define FUTEX_WAIT		0
+#define FUTEX_WAKE		1
+#define FUTEX_PRIVATE_FLAG	128L
+
+
+static long int gtm_futex_wait = FUTEX_WAIT | FUTEX_PRIVATE_FLAG;
+static long int gtm_futex_wake = FUTEX_WAKE | FUTEX_PRIVATE_FLAG;
+
+
+void
+futex_wait (int *addr, int val)
+{
+  long res;
+
+  res = sys_futex0 (addr, gtm_futex_wait, val);
+  if (__builtin_expect (res == -ENOSYS, 0))
+    {
+      gtm_futex_wait = FUTEX_WAIT;
+      gtm_futex_wake = FUTEX_WAKE;
+      res = sys_futex0 (addr, FUTEX_WAIT, val);
+    }
+  if (__builtin_expect (res < 0, 0))
+    {
+      if (res == -EWOULDBLOCK || res == -ETIMEDOUT)
+	;
+      else if (res == -EFAULT)
+	GTM_fatal ("futex failed (EFAULT %p)", addr);
+      else
+	GTM_fatal ("futex failed (%s)", strerror(-res));
+    }
+}
+
+
+long
+futex_wake (int *addr, int count)
+{
+  long res = sys_futex0 (addr, gtm_futex_wake, count);
+  if (__builtin_expect (res == -ENOSYS, 0))
+    {
+      gtm_futex_wait = FUTEX_WAIT;
+      gtm_futex_wake = FUTEX_WAKE;
+      res = sys_futex0 (addr, FUTEX_WAKE, count);
+    }
+  if (__builtin_expect (res < 0, 0))
+    GTM_fatal ("futex failed (%s)", strerror(-res));
+  else
+    return res;
+}
+
+} // namespace GTM