Add wrapper for RDTSCP instruction

xtoskrnl/ar/amd64/cpufunc.cc

@@ -573,6 +573,33 @@ AR::CpuFunc::ReadTimeStampCounter(VOID)
     return ((ULONGLONG)High << 32) | Low;
 }
 
+/**
+ * Reads the current value of the CPU's time-stamp counter and processor ID.
+ *
+ * @param TscAux
+ *        Supplies a pointer to a variable that receives the auxiliary TSC information (IA32_TSC_AUX).
+ *
+ * @return This routine returns the current instruction cycle count since the processor was last reset.
+ *
+ * @since XT 1.0
+ */
+XTCDECL
+ULONGLONG
+AR::CpuFunc::ReadTimeStampCounterProcessor(OUT PULONG TscAux)
+{
+    ULONG Low, High;
+
+    /* Execute the RDTSCP instruction */
+    __asm__ volatile("rdtscp"
+                     : "=a" (Low),
+                       "=d" (High),
+                       "=c" (*TscAux)
+    );
+
+    /* Combine the two 32-bit registers into a single 64-bit unsigned integer and return the value */
+    return ((ULONGLONG)High << 32) | Low;
+}
+
 /**
  * Orders memory accesses as seen by other processors, without fence.
  *

xtoskrnl/ar/i686/cpufunc.cc

@@ -543,6 +543,33 @@ AR::CpuFunc::ReadTimeStampCounter(VOID)
     return Value;
 }
 
+/**
+ * Reads the current value of the CPU's time-stamp counter and processor ID.
+ *
+ * @param TscAux
+ *        Supplies a pointer to a variable that receives the auxiliary TSC information (IA32_TSC_AUX).
+ *
+ * @return This routine returns the current instruction cycle count since the processor was last reset.
+ *
+ * @since XT 1.0
+ */
+XTCDECL
+ULONGLONG
+AR::CpuFunc::ReadTimeStampCounterProcessor(OUT PULONG TscAux)
+{
+    ULONG Low, High;
+
+    /* Execute the RDTSCP instruction */
+    __asm__ volatile("rdtscp"
+                     : "=a" (Low),
+                       "=d" (High),
+                       "=c" (*TscAux)
+    );
+
+    /* Combine the two 32-bit registers into a single 64-bit unsigned integer and return the value */
+    return ((ULONGLONG)High << 32) | Low;
+}
+
 /**
  * Orders memory accesses as seen by other processors, without fence.
  *

xtoskrnl/includes/ar/amd64/cpufunc.hh

@@ -40,6 +40,7 @@ namespace AR
             STATIC XTCDECL ULONGLONG ReadModelSpecificRegister(IN ULONG Register);
             STATIC XTCDECL UINT ReadMxCsrRegister(VOID);
             STATIC XTCDECL ULONGLONG ReadTimeStampCounter(VOID);
+            STATIC XTCDECL ULONGLONG ReadTimeStampCounterProcessor(OUT PULONG TscAux);
             STATIC XTCDECL VOID ReadWriteBarrier(VOID);
             STATIC XTCDECL VOID SetInterruptFlag(VOID);
             STATIC XTCDECL VOID StoreGlobalDescriptorTable(OUT PVOID Destination);

xtoskrnl/includes/ar/i686/cpufunc.hh

@@ -39,6 +39,7 @@ namespace AR
             STATIC XTCDECL ULONGLONG ReadModelSpecificRegister(IN ULONG Register);
             STATIC XTCDECL UINT ReadMxCsrRegister(VOID);
             STATIC XTCDECL ULONGLONG ReadTimeStampCounter(VOID);
+            STATIC XTCDECL ULONGLONG ReadTimeStampCounterProcessor(OUT PULONG TscAux);
             STATIC XTCDECL VOID ReadWriteBarrier(VOID);
             STATIC XTCDECL VOID SetInterruptFlag(VOID);
             STATIC XTCDECL VOID StoreGlobalDescriptorTable(OUT PVOID Destination);