arch: x86 -> x86_64 and build system changes

arch/x86_64/kernel/include/arch/cpu.h

@@ -0,0 +1,37 @@
+/**
+ * \file cpu.h
+ *  License details are found in the file LICENSE.
+ * \brief
+ *  Declare architecture-dependent types and functions to control CPU.
+ * \author Gou Nakamura  <go.nakamura.yw@hitachi-solutions.com>
+ *      Copyright (C) 2015  RIKEN AICS
+ */
+/*
+ * HISTORY
+ */
+
+#ifndef ARCH_CPU_H
+#define ARCH_CPU_H
+
+#define arch_barrier()	asm volatile("" : : : "memory")
+
+static inline void rmb(void)
+{
+	arch_barrier();
+}
+
+static inline void wmb(void)
+{
+	arch_barrier();
+}
+
+static unsigned long read_tsc(void)
+{
+	unsigned int low, high;
+
+	asm volatile("rdtsc" : "=a"(low), "=d"(high));
+
+	return (low | ((unsigned long)high << 32));
+}
+
+#endif /* ARCH_CPU_H */