--- a/hotspot/src/share/tools/ProjectCreator/BuildConfig.java	Fri Feb 03 12:08:55 2012 -0800
+++ b/hotspot/src/share/tools/ProjectCreator/BuildConfig.java	Fri Feb 03 12:20:11 2012 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2005, 2011, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2012, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -243,6 +243,7 @@
         sysDefines.add("_WINDOWS");
         sysDefines.add("HOTSPOT_BUILD_USER=\\\""+System.getProperty("user.name")+"\\\"");
         sysDefines.add("HOTSPOT_BUILD_TARGET=\\\""+get("Build")+"\\\"");
+        sysDefines.add("INCLUDE_TRACE");
         sysDefines.add("_JNI_IMPLEMENTATION_");
         if (vars.get("PlatformName").equals("Win32")) {
             sysDefines.add("HOTSPOT_LIB_ARCH=\\\"i386\\\"");

--- a/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp	Fri Feb 03 12:08:55 2012 -0800
+++ b/hotspot/src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp	Fri Feb 03 12:20:11 2012 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2011, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2012, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -5594,6 +5594,7 @@
     GenCollectedHeap::StrongRootsScope srs(gch);
     workers->run_task(&tsk);
   } else {
+    ReferenceProcessorMTDiscoveryMutator mt(ref_processor(), false);
     GenCollectedHeap::StrongRootsScope srs(gch);
     tsk.work(0);
   }
@@ -5608,6 +5609,8 @@
   ResourceMark rm;
   HandleMark   hm;
   GenCollectedHeap* gch = GenCollectedHeap::heap();
+  ReferenceProcessorMTDiscoveryMutator mt(ref_processor(), false);
+
   MarkRefsIntoAndScanClosure
     mrias_cl(_span, ref_processor(), &_markBitMap, &_modUnionTable,
              &_markStack, &_revisitStack, this,

--- a/hotspot/src/share/vm/runtime/arguments.cpp	Fri Feb 03 12:08:55 2012 -0800
+++ b/hotspot/src/share/vm/runtime/arguments.cpp	Fri Feb 03 12:20:11 2012 -0800
@@ -1400,10 +1400,11 @@
 
 void Arguments::set_parallel_gc_flags() {
   assert(UseParallelGC || UseParallelOldGC, "Error");
-  // If parallel old was requested, automatically enable parallel scavenge.
-  if (UseParallelOldGC && !UseParallelGC && FLAG_IS_DEFAULT(UseParallelGC)) {
-    FLAG_SET_DEFAULT(UseParallelGC, true);
+  // Enable ParallelOld unless it was explicitly disabled (cmd line or rc file).
+  if (FLAG_IS_DEFAULT(UseParallelOldGC)) {
+    FLAG_SET_DEFAULT(UseParallelOldGC, true);
   }
+  FLAG_SET_DEFAULT(UseParallelGC, true);
 
   // If no heap maximum was requested explicitly, use some reasonable fraction
   // of the physical memory, up to a maximum of 1GB.