--- /dev/null	2014-02-13 08:58:41.047762989 +0100
+++ new/src/share/vm/gc_implementation/g1/g1CodeCacheRemSet.cpp	2014-02-13 17:48:10.589769586 +0100
@@ -0,0 +1,191 @@
+/*
+ * Copyright (c) 2014, 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 "code/nmethod.hpp"
+#include "gc_implementation/g1/g1CodeCacheRemSet.hpp"
+#include "memory/iterator.hpp"
+
+G1CodeRootChunk::G1CodeRootChunk() : _alloc_next(NULL), _next(NULL), _prev(NULL) {
+  _alloc_next = first_element();
+}
+
+void G1CodeRootChunk::reset() {
+  _next = _prev = NULL;
+  _alloc_next = first_element();
+}
+
+void G1CodeRootChunk::nmethods_do(CodeBlobClosure* cl) {
+  nmethod** cur = first_element();
+  while (cur != _alloc_next) {
+    cl->do_code_blob(*cur);
+    cur++;
+  }
+}
+
+FreeList<G1CodeRootChunk> G1CodeRootSet::_free_list;
+size_t G1CodeRootSet::_num_chunks_handed_out = 0;
+
+G1CodeRootChunk* G1CodeRootSet::new_chunk() {
+  G1CodeRootChunk* result = _free_list.get_chunk_at_head();
+  if (result == NULL) {
+    result = new G1CodeRootChunk();
+  }
+  G1CodeRootSet::_num_chunks_handed_out++;
+  result->reset();
+  return result;
+}
+
+void G1CodeRootSet::free_chunk(G1CodeRootChunk* chunk) {
+  _free_list.return_chunk_at_head(chunk);
+  G1CodeRootSet::_num_chunks_handed_out--;
+}
+
+void G1CodeRootSet::free_all_chunks(FreeList<G1CodeRootChunk>* list) {
+  _free_list.prepend(list);
+}
+
+void G1CodeRootSet::purge_chunks(size_t keep_ratio) {
+  size_t keep = G1CodeRootSet::_num_chunks_handed_out * keep_ratio / 100;
+
+  if (keep >= (size_t)_free_list.count()) {
+    return;
+  }
+
+  FreeList<G1CodeRootChunk> temp;
+  temp.initialize();
+  temp.set_size(G1CodeRootChunk::word_size());
+
+  _free_list.getFirstNChunksFromList((size_t)_free_list.count() - keep, &temp);
+
+  G1CodeRootChunk* cur = temp.get_chunk_at_head();
+  while (cur != NULL) {
+    delete cur;
+    cur = temp.get_chunk_at_head();
+  }
+}
+
+size_t G1CodeRootSet::static_mem_size() {
+  return sizeof(_free_list) + sizeof(_num_chunks_handed_out);
+}
+
+size_t G1CodeRootSet::fl_mem_size() {
+  return _free_list.count() * _free_list.size();
+}
+
+void G1CodeRootSet::initialize() {
+  _free_list.initialize();
+  _free_list.set_size(G1CodeRootChunk::word_size());
+}
+
+G1CodeRootSet::G1CodeRootSet() : _list(), _length(0) {
+  _list.initialize();
+  _list.set_size(G1CodeRootChunk::word_size());
+}
+
+G1CodeRootSet::~G1CodeRootSet() {
+  clear();
+}
+
+void G1CodeRootSet::add(nmethod* method) {
+  if (!contains(method)) {
+    // Try to add the nmethod. If there is not enough space, get a new chunk.
+    if (_list.head() == NULL || _list.head()->is_full()) {
+      G1CodeRootChunk* cur = new_chunk();
+      _list.return_chunk_at_head(cur);
+    }
+    bool result = _list.head()->add(method);
+    guarantee(result, err_msg("Not able to add nmethod "PTR_FORMAT" to newly allocated chunk.", method));
+    _length++;
+  }
+}
+
+void G1CodeRootSet::remove(nmethod* method) {
+  G1CodeRootChunk* found = find(method);
+  if (found != NULL) {
+    bool result = found->remove(method);
+    guarantee(result, err_msg("could not find nmethod "PTR_FORMAT" during removal although we previously found it", method));
+    // eventually free completely emptied chunk
+    if (found->is_empty()) {
+      _list.remove_chunk(found);
+      free(found);
+    }
+    _length--;
+  }
+  assert(!contains(method), err_msg(PTR_FORMAT" still contains nmethod "PTR_FORMAT, this, method));
+}
+
+nmethod* G1CodeRootSet::pop() {
+  do {
+    G1CodeRootChunk* cur = _list.head();
+    if (cur == NULL) {
+      assert(_length == 0, "when there are no chunks, there should be no elements");
+      return NULL;
+    }
+    nmethod* result = cur->pop();
+    if (result != NULL) {
+      _length--;
+      return result;
+    } else {
+      free(_list.get_chunk_at_head());
+    }
+  } while (true);
+}
+
+G1CodeRootChunk* G1CodeRootSet::find(nmethod* method) {
+  G1CodeRootChunk* cur = _list.tail();
+  while (cur != NULL) {
+    if (cur->find(method)) {
+      return cur;
+    }
+    cur = (G1CodeRootChunk*)cur->prev();
+  }
+  return NULL;
+}
+
+void G1CodeRootSet::free(G1CodeRootChunk* chunk) {
+  free_chunk(chunk);
+}
+
+bool G1CodeRootSet::contains(nmethod* method) {
+  return find(method) != NULL;
+}
+
+void G1CodeRootSet::clear() {
+  free_all_chunks(&_list);
+  _length = 0;
+}
+
+void G1CodeRootSet::nmethods_do(CodeBlobClosure* blk) {
+  G1CodeRootChunk* cur = _list.head();
+  while (cur != NULL) {
+    cur->nmethods_do(blk);
+    cur = (G1CodeRootChunk*)cur->next();
+  }
+}
+
+size_t G1CodeRootSet::mem_size() {
+  return sizeof(this) + _list.count() * _list.size();
+}