2 files changed, 52 insertions, 1 deletions

diff --git a/lib/libc/i386/sys/Makefile.inc b/lib/libc/i386/sys/Makefile.inc
index 98a9c9e7d3943..9eefabca2ac38 100644
--- a/lib/libc/i386/sys/Makefile.inc
+++ b/lib/libc/i386/sys/Makefile.inc
@@ -5,7 +5,8 @@
 SRCS+=	i386_clr_watch.c i386_set_watch.c i386_vm86.c
 .endif
 SRCS+=	i386_get_fsbase.c i386_get_gsbase.c i386_get_ioperm.c i386_get_ldt.c \
-	i386_set_fsbase.c i386_set_gsbase.c i386_set_ioperm.c i386_set_ldt.c
+	i386_set_fsbase.c i386_set_gsbase.c i386_set_ioperm.c i386_set_ldt.c \
+	__vdso_gettc.c
 
 MDASM=	Ovfork.S brk.S cerror.S exect.S getcontext.S pipe.S ptrace.S \
 	reboot.S sbrk.S setlogin.S sigreturn.S syscall.S
diff --git a/lib/libc/i386/sys/__vdso_gettc.c b/lib/libc/i386/sys/__vdso_gettc.c
new file mode 100644
index 0000000000000..4419141a51979
--- /dev/null
+++ b/lib/libc/i386/sys/__vdso_gettc.c
@@ -0,0 +1,50 @@
+/*-
+ * Copyright (c) 2012 Konstantin Belousov <kib@FreeBSD.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <sys/time.h>
+#include <sys/vdso.h>
+#include <machine/cpufunc.h>
+
+static u_int
+__vdso_gettc_low(const struct vdso_timehands *th)
+{
+	uint32_t rv;
+
+	__asm __volatile("rdtsc; shrd %%cl, %%edx, %0"
+	    : "=a" (rv) : "c" (th->th_x86_shift) : "edx");
+	return (rv);
+}
+
+#pragma weak __vdso_gettc
+u_int
+__vdso_gettc(const struct vdso_timehands *th)
+{
+
+	return (th->th_x86_shift > 0 ? __vdso_gettc_low(th) : rdtsc32());
+}