kvmclock: initial implementation

kernel-src/include/x86-64/arch/msr.h

@@ -12,6 +12,8 @@
 #define MSR_GSBASE 0xC0000101
 #define MSR_KERNELGSBASE 0xC0000102
 
+#define MSR_KVM_SYSTEM_TIME_NEW 0x4b564d01
+
 static inline uint64_t rdmsr(uint32_t which) {
 	uint64_t low,high;
 	asm volatile("rdmsr" : "=a"(low), "=d"(high) : "c"(which));

kernel-src/include/x86-64/arch/tsc.h

@@ -0,0 +1,11 @@
+#ifndef _TSC_H
+#define _TSC_H
+
+static inline uint64_t rdtsc_serialized(void) {
+	uint32_t high;
+	uint32_t low;
+	asm volatile("cpuid; rdtsc;" : "=a"(low), "=d"(high) : : "rbx", "rcx");
+	return ((uint64_t)high << 32) | low;
+}
+
+#endif