/*

 * Copyright (c) 2007, 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.

 *

 */

class CardTableRS;   // fwd decl

class ConcurrentMarkSweepGeneration;

// A PermGen implemented with a CMS space, collected by a CMS collector.

class CMSPermGen:  public PermGen {

  friend class VMStructs;

 protected:

  // The "generation" view.

  ConcurrentMarkSweepGeneration* _gen;

  // Override default implementation from PermGen

  virtual HeapWord* request_expand_and_allocate(Generation* gen, size_t size,

                                                GCCause::Cause prev_cause);

 public:

  CMSPermGen(ReservedSpace rs, size_t initial_byte_size,

             CardTableRS* ct, FreeBlockDictionary::DictionaryChoice);

  HeapWord* mem_allocate(size_t size);

  void compute_new_size();

  Generation* as_gen() const { return _gen; }

};

// This is the "generation" view of a CMSPermGen.

class CMSPermGenGen: public ConcurrentMarkSweepGeneration {

  // Abstractly, this is a subtype that gets access to protected fields.

  friend class CMSPermGen;

public:

  CMSPermGenGen(ReservedSpace rs, size_t initial_byte_size,

                       int level, CardTableRS* ct):

    // See comments in the constructor for CompactibleFreeListSpace

    // regarding not using adaptive free lists for a perm gen.

    ConcurrentMarkSweepGeneration(rs, initial_byte_size, // MinPermHeapExapnsion

      level, ct, false /* use adaptive freelists */,

      (FreeBlockDictionary::DictionaryChoice)CMSDictionaryChoice)

  {}

  void initialize_performance_counters();

  const char* name() const {

    return "concurrent-mark-sweep perm gen";

  }

  const char* short_name() const {

    return "CMS Perm";

  }

  bool must_be_youngest() const { return false; }

  bool must_be_oldest() const { return false; }

};