Implement KeGetCurrentProcessorNumber() routine

xtoskrnl/ke/amd64/proc.c

@@ -38,6 +38,20 @@ KeGetCurrentProcessorControlBlock(VOID)
     return (PKPROCESSOR_CONTROL_BLOCK)ArReadGSQuadWord(FIELD_OFFSET(KPROCESSOR_BLOCK, CurrentPrcb));
 }
 
+/**
+ * Gets the number of the currently executing processor.
+ *
+ * @return This routine returns the zero-indexed processor number.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+ULONG
+KeGetCurrentProcessorNumber(VOID)
+{
+    return (ULONG)ArReadGSQuadWord(FIELD_OFFSET(KPROCESSOR_BLOCK, CpuNumber));
+}
+
 /**
  * Gets the current thread running on the currently executing processor.
  *