8133821: Refactor initialization of the heap and the collector policy

Reviewed-by: pliden, tschatzl

hotspot/src/share/vm/memory/universe.cpp

@@ -694,13 +694,29 @@ jint universe_init() {
   return JNI_OK;
 }
 
-template <class Heap, class Policy>
+CollectedHeap* Universe::create_heap() {
-jint Universe::create_heap() {
   assert(_collectedHeap == NULL, "Heap already created");
-  Policy* policy = new Policy();
+#if !INCLUDE_ALL_GCS
-  policy->initialize_all();
+  if (UseParallelGC) {
-  _collectedHeap = new Heap(policy);
+    fatal("UseParallelGC not supported in this VM.");
-  return _collectedHeap->initialize();
+  } else if (UseG1GC) {
+    fatal("UseG1GC not supported in this VM.");
+  } else if (UseConcMarkSweepGC) {
+    fatal("UseConcMarkSweepGC not supported in this VM.");
+#else
+  if (UseParallelGC) {
+    return Universe::create_heap_with_policy<ParallelScavengeHeap, GenerationSizer>();
+  } else if (UseG1GC) {
+    return Universe::create_heap_with_policy<G1CollectedHeap, G1CollectorPolicyExt>();
+  } else if (UseConcMarkSweepGC) {
+    return Universe::create_heap_with_policy<GenCollectedHeap, ConcurrentMarkSweepPolicy>();
+#endif
+  } else if (UseSerialGC) {
+    return Universe::create_heap_with_policy<GenCollectedHeap, MarkSweepPolicy>();
+  }
+
+  ShouldNotReachHere();
+  return NULL;
 }
 
 // Choose the heap base address and oop encoding mode
@@ -714,27 +730,12 @@ jint Universe::create_heap() {
 jint Universe::initialize_heap() {
   jint status = JNI_ERR;
 
-#if !INCLUDE_ALL_GCS
+  _collectedHeap = create_heap_ext();
-  if (UseParallelGC) {
+  if (_collectedHeap == NULL) {
-    fatal("UseParallelGC not supported in this VM.");
+    _collectedHeap = create_heap();
-  } else if (UseG1GC) {
-    fatal("UseG1GC not supported in this VM.");
-  } else if (UseConcMarkSweepGC) {
-    fatal("UseConcMarkSweepGC not supported in this VM.");
-#else
-  if (UseParallelGC) {
-    status = Universe::create_heap<ParallelScavengeHeap, GenerationSizer>();
-  } else if (UseG1GC) {
-    status = Universe::create_heap<G1CollectedHeap, G1CollectorPolicyExt>();
-  } else if (UseConcMarkSweepGC) {
-    status = Universe::create_heap<GenCollectedHeap, ConcurrentMarkSweepPolicy>();
-#endif
-  } else if (UseSerialGC) {
-    status = Universe::create_heap<GenCollectedHeap, MarkSweepPolicy>();
-  } else {
-    ShouldNotReachHere();
   }
 
+  status = _collectedHeap->initialize();
   if (status != JNI_OK) {
     return status;
   }

hotspot/src/share/vm/memory/universe.hpp

@@ -214,7 +214,9 @@ class Universe: AllStatic {
   static size_t _heap_capacity_at_last_gc;
   static size_t _heap_used_at_last_gc;
 
-  template <class Heap, class Policy> static jint create_heap();
+  template <class Heap, class Policy> static CollectedHeap* create_heap_with_policy();
+  static CollectedHeap* create_heap();
+  static CollectedHeap* create_heap_ext();
   static jint initialize_heap();
   static void initialize_basic_type_mirrors(TRAPS);
   static void fixup_mirrors(TRAPS);

hotspot/src/share/vm/memory/universe.inline.hpp

@@ -49,4 +49,11 @@ inline void Universe::set_allocation_context_notification_obj(oop obj) {
   _allocation_context_notification_obj = obj;
 }
 
+template <class Heap, class Policy>
+CollectedHeap* Universe::create_heap_with_policy() {
+  Policy* policy = new Policy();
+  policy->initialize_all();
+  return new Heap(policy);
+}
+
 #endif // SHARE_VM_MEMORY_UNIVERSE_INLINE_HPP

hotspot/src/share/vm/memory/universe_ext.cpp

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2015, 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
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "memory/universe.hpp"
+
+CollectedHeap* Universe::create_heap_ext() {
+  return NULL;
+}