Add x86 32 bit vDSO time function support

Linux 3.15 adds support for clock_gettime, gettimeofday, and time vDSO
(commit id 37c975545ec63320789962bf307f000f08fabd48).  This patch adds
GLIBC supports to use such symbol when they are avaiable.

Along with x86 vDSO support, this patch cleanup x86_64 code by moving
all common code to x86 common folder.  Only init-first.c is different
between implementations.

1 files changed, 31 insertions, 0 deletions

diff --git a/sysdeps/unix/sysv/linux/x86/libc-vdso.h b/sysdeps/unix/sysv/linux/x86/libc-vdso.h
new file mode 100644
index 0000000000..03ff875035
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86/libc-vdso.h
@@ -0,0 +1,31 @@
+/* Resolve function pointers to VDSO functions.
+   Copyright (C) 2005-2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library 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.
+
+   The GNU C Library 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 the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _LIBC_VDSO_H
+#define _LIBC_VDSO_H
+
+#include <time.h>
+#include <sys/time.h>
+
+#ifdef SHARED
+
+extern long int (*__vdso_clock_gettime) (clockid_t, struct timespec *);
+
+#endif
+
+#endif /* _LIBC_VDSO_H */