cpu: Unify SimpleCPU and O3 CPU serialization code

The O3 CPU used to copy its thread context to a SimpleThread in order
to do serialization. This was a bit of a hack involving two static
SimpleThread instances and a magic constructor that was only used by
the O3 CPU.

This patch moves the ThreadContext serialization code into two global
procedures that, in addition to the normal serialization parameters,
take a ThreadContext reference as a parameter. This allows us to reuse
the serialization code in all ThreadContext implementations.

4 files changed, 40 insertions, 40 deletions

diff --git a/src/cpu/o3/cpu.cc b/src/cpu/o3/cpu.cc
index 0419a6173..2613a8da3 100644
--- a/src/cpu/o3/cpu.cc
+++ b/src/cpu/o3/cpu.cc
@@ -1097,16 +1097,9 @@ FullO3CPU<Impl>::serialize(std::ostream &os)
     nameOut(os, csprintf("%s.tickEvent", name()));
     tickEvent.serialize(os);
 
-    // Use SimpleThread's ability to checkpoint to make it easier to
-    // write out the registers.  Also make this static so it doesn't
-    // get instantiated multiple times (causes a panic in statistics).
-    static SimpleThread temp;
-
-    ThreadID size = thread.size();
-    for (ThreadID i = 0; i < size; i++) {
+    for (ThreadID i = 0; i < thread.size(); i++) {
         nameOut(os, csprintf("%s.xc.%i", name(), i));
-        temp.copyTC(thread[i]->getTC());
-        temp.serialize(os);
+        thread[i]->serialize(os);
     }
 }
 
@@ -1119,16 +1112,11 @@ FullO3CPU<Impl>::unserialize(Checkpoint *cp, const std::string &section)
     BaseCPU::unserialize(cp, section);
     tickEvent.unserialize(cp, csprintf("%s.tickEvent", section));
 
-    // Use SimpleThread's ability to checkpoint to make it easier to
-    // read in the registers.  Also make this static so it doesn't
-    // get instantiated multiple times (causes a panic in statistics).
-    static SimpleThread temp;
-
-    ThreadID size = thread.size();
-    for (ThreadID i = 0; i < size; i++) {
-        temp.copyTC(thread[i]->getTC());
-        temp.unserialize(cp, csprintf("%s.xc.%i", section, i));
-        thread[i]->getTC()->copyArchRegs(temp.getTC());
+    for (ThreadID i = 0; i < thread.size(); i++) {
+        thread[i]->unserialize(cp,
+                               csprintf("%s.xc.%i", section, i));
+        if (thread[i]->status() == ThreadContext::Active)
+            activateThread(i);
     }
 }
 
diff --git a/src/cpu/o3/thread_context.hh b/src/cpu/o3/thread_context.hh
index 1efcfff9c..4201878af 100755
--- a/src/cpu/o3/thread_context.hh
+++ b/src/cpu/o3/thread_context.hh
@@ -153,11 +153,6 @@ class O3ThreadContext : public ThreadContext
     /** Registers statistics associated with this TC. */
     virtual void regStats(const std::string &name);
 
-    /** Serializes state. */
-    virtual void serialize(std::ostream &os);
-    /** Unserializes state. */
-    virtual void unserialize(Checkpoint *cp, const std::string &section);
-
     /** Reads the last tick that this thread was activated on. */
     virtual Tick readLastActivate();
     /** Reads the last tick that this thread was suspended on. */
diff --git a/src/cpu/o3/thread_context_impl.hh b/src/cpu/o3/thread_context_impl.hh
index 4ab793538..2de6dbc1b 100755
--- a/src/cpu/o3/thread_context_impl.hh
+++ b/src/cpu/o3/thread_context_impl.hh
@@ -159,22 +159,6 @@ O3ThreadContext<Impl>::regStats(const std::string &name)
 }
 
 template <class Impl>
-void
-O3ThreadContext<Impl>::serialize(std::ostream &os)
-{
-    if (FullSystem && thread->kernelStats)
-        thread->kernelStats->serialize(os);
-}
-
-template <class Impl>
-void
-O3ThreadContext<Impl>::unserialize(Checkpoint *cp, const std::string &section)
-{
-    if (FullSystem && thread->kernelStats)
-        thread->kernelStats->unserialize(cp, section);
-}
-
-template <class Impl>
 Tick
 O3ThreadContext<Impl>::readLastActivate()
 {
diff --git a/src/cpu/o3/thread_state.hh b/src/cpu/o3/thread_state.hh
index 96ccfc95c..406c798f0 100644
--- a/src/cpu/o3/thread_state.hh
+++ b/src/cpu/o3/thread_state.hh
@@ -1,4 +1,16 @@
 /*
+ * Copyright (c) 2012 ARM Limited
+ * All rights reserved
+ *
+ * The license below extends only to copyright in the software and shall
+ * not be construed as granting a license to any other intellectual
+ * property including but not limited to intellectual property relating
+ * to a hardware implementation of the functionality of the software
+ * licensed hereunder.  You may use the software subject to the license
+ * terms below provided that you ensure that this notice is replicated
+ * unmodified and in its entirety in all distributions of the software,
+ * modified or unmodified, in source code or in binary form.
+ *
  * Copyright (c) 2006 The Regents of The University of Michigan
  * All rights reserved.
  *
@@ -99,6 +111,27 @@ struct O3ThreadState : public ThreadState {
         profilePC = 3;
     }
 
+    void serialize(std::ostream &os)
+    {
+        ThreadState::serialize(os);
+        // Use the ThreadContext serialization helper to serialize the
+        // TC.
+        ::serialize(*tc, os);
+    }
+
+    void unserialize(Checkpoint *cp, const std::string &section)
+    {
+        // Prevent squashing - we don't have any instructions in
+        // flight that we need to squash since we just instantiated a
+        // clean system.
+        noSquashFromTC = true;
+        ThreadState::unserialize(cp, section);
+        // Use the ThreadContext serialization helper to unserialize
+        // the TC.
+        ::unserialize(*tc, cp, section);
+        noSquashFromTC = false;
+    }
+
     /** Pointer to the ThreadContext of this thread. */
     ThreadContext *tc;