--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/memory/metablock.cpp	Thu Nov 29 10:09:04 2012 -0800
@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 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
+ * 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/allocation.hpp"
+#include "memory/metablock.hpp"
+#include "utilities/copy.hpp"
+#include "utilities/debug.hpp"
+
+// Blocks of space for metadata are allocated out of Metachunks.
+//
+// Metachunk are allocated out of MetadataVirtualspaces and once
+// allocated there is no explicit link between a Metachunk and
+// the MetadataVirtualspaces from which it was allocated.
+//
+// Each SpaceManager maintains a
+// list of the chunks it is using and the current chunk.  The current
+// chunk is the chunk from which allocations are done.  Space freed in
+// a chunk is placed on the free list of blocks (BlockFreelist) and
+// reused from there.
+//
+// Future modification
+//
+// The Metachunk can conceivable be replaced by the Chunk in
+// allocation.hpp.  Note that the latter Chunk is the space for
+// allocation (allocations from the chunk are out of the space in
+// the Chunk after the header for the Chunk) where as Metachunks
+// point to space in a VirtualSpace.  To replace Metachunks with
+// Chunks, change Chunks so that they can be allocated out of a VirtualSpace.
+size_t Metablock::_min_block_byte_size = sizeof(Metablock);
+
+#ifdef ASSERT
+size_t Metablock::_overhead =
+  Chunk::aligned_overhead_size(sizeof(Metablock)) / BytesPerWord;
+#else
+size_t Metablock::_overhead = 0;
+#endif
+
+// New blocks returned by the Metaspace are zero initialized.
+// We should fix the constructors to not assume this instead.
+Metablock* Metablock::initialize(MetaWord* p, size_t word_size) {
+  if (p == NULL) {
+    return NULL;
+  }
+
+  Metablock* result = (Metablock*) p;
+
+  // Clear the memory
+  Copy::fill_to_aligned_words((HeapWord*)result, word_size);
+#ifdef ASSERT
+  result->set_word_size(word_size);
+#endif
+  return result;
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/memory/metachunk.cpp	Thu Nov 29 10:09:04 2012 -0800
@@ -0,0 +1,117 @@
+/*
+ * Copyright (c) 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
+ * 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/allocation.hpp"
+#include "memory/metachunk.hpp"
+#include "utilities/copy.hpp"
+#include "utilities/debug.hpp"
+
+//
+// Future modification
+//
+// The Metachunk can conceivable be replaced by the Chunk in
+// allocation.hpp.  Note that the latter Chunk is the space for
+// allocation (allocations from the chunk are out of the space in
+// the Chunk after the header for the Chunk) where as Metachunks
+// point to space in a VirtualSpace.  To replace Metachunks with
+// Chunks, change Chunks so that they can be allocated out of a VirtualSpace.
+
+const size_t metadata_chunk_initialize = 0xf7f7f7f7;
+
+size_t Metachunk::_overhead =
+  Chunk::aligned_overhead_size(sizeof(Metachunk)) / BytesPerWord;
+
+// Metachunk methods
+
+Metachunk* Metachunk::initialize(MetaWord* ptr, size_t word_size) {
+  // Set bottom, top, and end.  Allow space for the Metachunk itself
+  Metachunk* chunk = (Metachunk*) ptr;
+
+  MetaWord* chunk_bottom = ptr + _overhead;
+  chunk->set_bottom(ptr);
+  chunk->set_top(chunk_bottom);
+  MetaWord* chunk_end = ptr + word_size;
+  assert(chunk_end > chunk_bottom, "Chunk must be too small");
+  chunk->set_end(chunk_end);
+  chunk->set_next(NULL);
+  chunk->set_word_size(word_size);
+#ifdef ASSERT
+  size_t data_word_size = pointer_delta(chunk_end, chunk_bottom, sizeof(MetaWord));
+  Copy::fill_to_words((HeapWord*) chunk_bottom, data_word_size, metadata_chunk_initialize);
+#endif
+  return chunk;
+}
+
+
+MetaWord* Metachunk::allocate(size_t word_size) {
+  MetaWord* result = NULL;
+  // If available, bump the pointer to allocate.
+  if (free_word_size() >= word_size) {
+    result = _top;
+    _top = _top + word_size;
+  }
+  return result;
+}
+
+// _bottom points to the start of the chunk including the overhead.
+size_t Metachunk::used_word_size() {
+  return pointer_delta(_top, _bottom, sizeof(MetaWord));
+}
+
+size_t Metachunk::free_word_size() {
+  return pointer_delta(_end, _top, sizeof(MetaWord));
+}
+
+size_t Metachunk::capacity_word_size() {
+  return pointer_delta(_end, _bottom, sizeof(MetaWord));
+}
+
+void Metachunk::print_on(outputStream* st) const {
+  st->print_cr("Metachunk:"
+               " bottom " PTR_FORMAT " top " PTR_FORMAT
+               " end " PTR_FORMAT " size " SIZE_FORMAT,
+               bottom(), top(), end(), word_size());
+}
+
+#ifndef PRODUCT
+void Metachunk::mangle() {
+  // Mangle the payload of the chunk and not the links that
+  // maintain list of chunks.
+  HeapWord* start = (HeapWord*)(bottom() + overhead());
+  size_t word_size = capacity_word_size() - overhead();
+  Copy::fill_to_words(start, word_size, metadata_chunk_initialize);
+}
+#endif // PRODUCT
+
+void Metachunk::verify() {
+#ifdef ASSERT
+  // Cannot walk through the blocks unless the blocks have
+  // headers with sizes.
+  assert(_bottom <= _top &&
+         _top <= _end,
+         "Chunk has been smashed");
+#endif
+  return;
+}

--- a/hotspot/src/share/vm/memory/metaspace.cpp	Fri Nov 30 11:46:17 2012 -0800
+++ b/hotspot/src/share/vm/memory/metaspace.cpp	Thu Nov 29 10:09:04 2012 -0800
@@ -52,7 +52,6 @@
 const uint metadata_deallocate_a_lot_block = 10;
 const uint metadata_deallocate_a_lock_chunk = 3;
 size_t const allocation_from_dictionary_limit = 64 * K;
-const size_t metadata_chunk_initialize = 0xf7f7f7f7;
 const size_t metadata_deallocate = 0xf5f5f5f5;
 
 MetaWord* last_allocated = 0;
@@ -92,22 +91,6 @@
 // chunk is the chunk from which allocations are done.  Space freed in
 // a chunk is placed on the free list of blocks (BlockFreelist) and
 // reused from there.
-//
-// Future modification
-//
-// The Metachunk can conceivable be replaced by the Chunk in
-// allocation.hpp.  Note that the latter Chunk is the space for
-// allocation (allocations from the chunk are out of the space in
-// the Chunk after the header for the Chunk) where as Metachunks
-// point to space in a VirtualSpace.  To replace Metachunks with
-// Chunks, change Chunks so that they can be allocated out of a VirtualSpace.
-size_t Metablock::_min_block_byte_size = sizeof(Metablock);
-#ifdef ASSERT
-  size_t Metablock::_overhead =
-    Chunk::aligned_overhead_size(sizeof(Metablock)) / BytesPerWord;
-#else
-  size_t Metablock::_overhead = 0;
-#endif
 
 // Pointer to list of Metachunks.
 class ChunkList VALUE_OBJ_CLASS_SPEC {
@@ -623,6 +606,7 @@
   void locked_print_chunks_in_use_on(outputStream* st) const;
 
   void verify();
+  void verify_chunk_size(Metachunk* chunk);
   NOT_PRODUCT(void mangle_freed_chunks();)
 #ifdef ASSERT
   void verify_allocation_total();
@@ -631,8 +615,6 @@
 
 uint const SpaceManager::_small_chunk_limit = 4;
 
-
-
 const char* SpaceManager::_expand_lock_name =
   "SpaceManager chunk allocation lock";
 const int SpaceManager::_expand_lock_rank = Monitor::leaf - 1;
@@ -641,103 +623,6 @@
             SpaceManager::_expand_lock_name,
             Mutex::_allow_vm_block_flag);
 
-size_t Metachunk::_overhead =
-  Chunk::aligned_overhead_size(sizeof(Metachunk)) / BytesPerWord;
-
-// New blocks returned by the Metaspace are zero initialized.
-// We should fix the constructors to not assume this instead.
-Metablock* Metablock::initialize(MetaWord* p, size_t word_size) {
-  if (p == NULL) {
-    return NULL;
-  }
-
-  Metablock* result = (Metablock*) p;
-
-  // Clear the memory
-  Copy::fill_to_aligned_words((HeapWord*)result, word_size);
-#ifdef ASSERT
-  result->set_word_size(word_size);
-#endif
-  return result;
-}
-
-// Metachunk methods
-
-Metachunk* Metachunk::initialize(MetaWord* ptr, size_t word_size) {
-  // Set bottom, top, and end.  Allow space for the Metachunk itself
-  Metachunk* chunk = (Metachunk*) ptr;
-
-  MetaWord* chunk_bottom = ptr + _overhead;
-  chunk->set_bottom(ptr);
-  chunk->set_top(chunk_bottom);
-  MetaWord* chunk_end = ptr + word_size;
-  assert(chunk_end > chunk_bottom, "Chunk must be too small");
-  chunk->set_end(chunk_end);
-  chunk->set_next(NULL);
-  chunk->set_word_size(word_size);
-#ifdef ASSERT
-  size_t data_word_size = pointer_delta(chunk_end, chunk_bottom, sizeof(MetaWord));
-  Copy::fill_to_words((HeapWord*) chunk_bottom, data_word_size, metadata_chunk_initialize);
-#endif
-  return chunk;
-}
-
-
-MetaWord* Metachunk::allocate(size_t word_size) {
-  MetaWord* result = NULL;
-  // If available, bump the pointer to allocate.
-  if (free_word_size() >= word_size) {
-    result = _top;
-    _top = _top + word_size;
-  }
-  return result;
-}
-
-// _bottom points to the start of the chunk including the overhead.
-size_t Metachunk::used_word_size() {
-  return pointer_delta(_top, _bottom, sizeof(MetaWord));
-}
-
-size_t Metachunk::free_word_size() {
-  return pointer_delta(_end, _top, sizeof(MetaWord));
-}
-
-size_t Metachunk::capacity_word_size() {
-  return pointer_delta(_end, _bottom, sizeof(MetaWord));
-}
-
-void Metachunk::print_on(outputStream* st) const {
-  st->print_cr("Metachunk:"
-               " bottom " PTR_FORMAT " top " PTR_FORMAT
-               " end " PTR_FORMAT " size " SIZE_FORMAT,
-               bottom(), top(), end(), word_size());
-}
-
-#ifndef PRODUCT
-void Metachunk::mangle() {
-  // Mangle the payload of the chunk and not the links that
-  // maintain list of chunks.
-  HeapWord* start = (HeapWord*)(bottom() + overhead());
-  size_t word_size = capacity_word_size() - overhead();
-  Copy::fill_to_words(start, word_size, metadata_chunk_initialize);
-}
-#endif // PRODUCT
-
-void Metachunk::verify() {
-#ifdef ASSERT
-  // Cannot walk through the blocks unless the blocks have
-  // headers with sizes.
-  assert(_bottom <= _top &&
-         _top <= _end,
-         "Chunk has been smashed");
-  assert(SpaceManager::is_humongous(_word_size) ||
-         _word_size == SpaceManager::MediumChunk ||
-         _word_size == SpaceManager::SmallChunk,
-         "Chunk size is wrong");
-#endif
-  return;
-}
-
 // BlockFreelist methods
 
 BlockFreelist::BlockFreelist() : _dictionary(NULL) {}
@@ -2214,12 +2099,21 @@
       Metachunk* curr = chunks_in_use(i);
       while (curr != NULL) {
         curr->verify();
+        verify_chunk_size(curr);
         curr = curr->next();
       }
     }
   }
 }
 
+void SpaceManager::verify_chunk_size(Metachunk* chunk) {
+  assert(is_humongous(chunk->word_size()) ||
+         chunk->word_size() == MediumChunk ||
+         chunk->word_size() == SmallChunk,
+         "Chunk size is wrong");
+  return;
+}
+
 #ifdef ASSERT
 void SpaceManager::verify_allocation_total() {
 #if 0