add rdtsc() to match amd64

ok mikeb@ mlarkin@

diff --git a/sys/arch/i386/include/cpufunc.h b/sys/arch/i386/include/cpufunc.h
index 8ae5382..fb745da 100644 (file)
--- a/sys/arch/i386/include/cpufunc.h
+++ b/sys/arch/i386/include/cpufunc.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: cpufunc.h,v 1.25 2017/05/27 12:21:50 tedu Exp $       */
+/*     $OpenBSD: cpufunc.h,v 1.26 2017/06/17 09:32:26 jmatthew Exp $   */
 /*     $NetBSD: cpufunc.h,v 1.8 1994/10/27 04:15:59 cgd Exp $  */
 
 /*
@@ -217,6 +217,15 @@ mfence(void)
        __asm volatile("mfence" : : : "memory");
 }
 
+static __inline u_int64_t
+rdtsc(void)
+{
+       uint64_t tsc;
+
+       __asm volatile("rdtsc" : "=A" (tsc));
+       return (tsc);
+}
+
 static __inline void
 wrmsr(u_int msr, u_int64_t newval)
 {