implement thread_get_nice & thread_get_recent_cpu

src/threads/thread.c

@@ -4,6 +4,7 @@
 #include <random.h>
 #include <stdio.h>
 #include <string.h>
+#include "threads/fixed-point.h"
 #include "threads/flags.h"
 #include "threads/interrupt.h"
 #include "threads/intr-stubs.h"
@@ -399,8 +400,7 @@ thread_get_load_avg (void)
 int
 thread_get_recent_cpu (void) 
 {
-  /* Not yet implemented. */
-  return 0;
+  return fp_round (fp_mul_int (thread_current ()->recent_cpu, 100));
 }
 
 /* Idle thread.  Executes when no other thread is ready to run.