After a checkpoint (and thus a stats reset), the not_idle_fraction/notIdleFraction statistic is really wrong.

The notIdleFraction statistic isn't updated when the statistics reset, probably because the cpu Status information
was pulled into the atomic and timing cpus. This changeset pulls Status back into the BaseSimpleCPU object. Anyone
care to comment on the odd naming of the Status instance? It shouldn't just be status because that is confusing
with Port::Status, but _status seems a bit strage too.

src/cpu/simple/atomic.cc

@@ -176,8 +176,6 @@ AtomicSimpleCPU::serialize(ostream &os)
 {
     SimObject::State so_state = SimObject::getState();
     SERIALIZE_ENUM(so_state);
-    Status _status = status();
-    SERIALIZE_ENUM(_status);
     BaseSimpleCPU::serialize(os);
     nameOut(os, csprintf("%s.tickEvent", name()));
     tickEvent.serialize(os);
@@ -188,7 +186,6 @@ AtomicSimpleCPU::unserialize(Checkpoint *cp, const string &section)
 {
     SimObject::State so_state;
     UNSERIALIZE_ENUM(so_state);
-    UNSERIALIZE_ENUM(_status);
     BaseSimpleCPU::unserialize(cp, section);
     tickEvent.unserialize(cp, csprintf("%s.tickEvent", section));
 }
@@ -213,7 +210,7 @@ AtomicSimpleCPU::resume()
 void
 AtomicSimpleCPU::switchOut()
 {
-    assert(status() == Running || status() == Idle);
+    assert(_status == Running || _status == Idle);
     _status = SwitchedOut;
 
     tickEvent.squash();

src/cpu/simple/atomic.hh

@@ -48,19 +48,6 @@ class AtomicSimpleCPU : public BaseSimpleCPU
 
     virtual void init();
 
-  public:
-    //
-    enum Status {
-        Running,
-        Idle,
-        SwitchedOut
-    };
-
-  protected:
-    Status _status;
-
-    Status status() const { return _status; }
-
   private:
 
     struct TickEvent : public Event

src/cpu/simple/base.cc

@@ -174,12 +174,13 @@ void
 BaseSimpleCPU::resetStats()
 {
 //    startNumInst = numInst;
-    // notIdleFraction = (_status != Idle);
+     notIdleFraction = (_status != Idle);
 }
 
 void
 BaseSimpleCPU::serialize(ostream &os)
 {
+    SERIALIZE_ENUM(_status);
     BaseCPU::serialize(os);
 //    SERIALIZE_SCALAR(inst);
     nameOut(os, csprintf("%s.xc.0", name()));
@@ -189,6 +190,7 @@ BaseSimpleCPU::serialize(ostream &os)
 void
 BaseSimpleCPU::unserialize(Checkpoint *cp, const string &section)
 {
+    UNSERIALIZE_ENUM(_status);
     BaseCPU::unserialize(cp, section);
 //    UNSERIALIZE_SCALAR(inst);
     thread->unserialize(cp, csprintf("%s.xc.0", section));

src/cpu/simple/base.hh

@@ -129,6 +129,20 @@ class BaseSimpleCPU : public BaseCPU
   protected:
     int cpuId;
 
+    enum Status {
+        Idle,
+        Running,
+        IcacheRetry,
+        IcacheWaitResponse,
+        IcacheWaitSwitch,
+        DcacheRetry,
+        DcacheWaitResponse,
+        DcacheWaitSwitch,
+        SwitchedOut
+    };
+
+    Status _status;
+
   public:
 
 #if FULL_SYSTEM

src/cpu/simple/timing.cc

@@ -145,7 +145,7 @@ TimingSimpleCPU::drain(Event *drain_event)
 {
     // TimingSimpleCPU is ready to drain if it's not waiting for
     // an access to complete.
-    if (status() == Idle || status() == Running || status() == SwitchedOut) {
+    if (_status == Idle || _status == Running || _status == SwitchedOut) {
         changeState(SimObject::Drained);
         return 0;
     } else {
@@ -179,7 +179,7 @@ TimingSimpleCPU::resume()
 void
 TimingSimpleCPU::switchOut()
 {
-    assert(status() == Running || status() == Idle);
+    assert(_status == Running || _status == Idle);
     _status = SwitchedOut;
     numCycles += tickToCycles(curTick - previousTick);
 

src/cpu/simple/timing.hh

@@ -46,24 +46,6 @@ class TimingSimpleCPU : public BaseSimpleCPU
     virtual void init();
 
   public:
-    //
-    enum Status {
-        Idle,
-        Running,
-        IcacheRetry,
-        IcacheWaitResponse,
-        IcacheWaitSwitch,
-        DcacheRetry,
-        DcacheWaitResponse,
-        DcacheWaitSwitch,
-        SwitchedOut
-    };
-
-  protected:
-    Status _status;
-
-    Status status() const { return _status; }
-
     Event *drainEvent;
 
   private: