1 /*
   2  * Copyright (c) 2001, 2005, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 class PSAdaptiveSizePolicy;
  26 class PSYoungGen;
  27 class PSOldGen;
  28 
  29 class PSMarkSweep : public MarkSweep {
  30  private:
  31   static elapsedTimer        _accumulated_time;
  32   static unsigned int        _total_invocations;
  33   static jlong               _time_of_last_gc;   // ms
  34   static CollectorCounters*  _counters;
  35 
  36   // Closure accessors
  37   static OopClosure* mark_and_push_closure() { return &MarkSweep::mark_and_push_closure; }
  38   static VoidClosure* follow_stack_closure() { return (VoidClosure*)&MarkSweep::follow_stack_closure; }
  39   static OopClosure* adjust_pointer_closure() { return (OopClosure*)&MarkSweep::adjust_pointer_closure; }
  40   static OopClosure* adjust_root_pointer_closure() { return (OopClosure*)&MarkSweep::adjust_root_pointer_closure; }
  41   static BoolObjectClosure* is_alive_closure() { return (BoolObjectClosure*)&MarkSweep::is_alive; }
  42 
  43  debug_only(public:)  // Used for PSParallelCompact debugging
  44   // Mark live objects
  45   static void mark_sweep_phase1(bool clear_all_softrefs);
  46   // Calculate new addresses
  47   static void mark_sweep_phase2();
  48  debug_only(private:) // End used for PSParallelCompact debugging
  49   // Update pointers
  50   static void mark_sweep_phase3();
  51   // Move objects to new positions
  52   static void mark_sweep_phase4();
  53 
  54  debug_only(public:)  // Used for PSParallelCompact debugging
  55   // Temporary data structures for traversal and storing/restoring marks
  56   static void allocate_stacks();
  57   static void deallocate_stacks();
  58   static void set_ref_processor(ReferenceProcessor* rp) {  // delete this method
  59     _ref_processor = rp;
  60   }
  61  debug_only(private:) // End used for PSParallelCompact debugging
  62 
  63   // If objects are left in eden after a collection, try to move the boundary
  64   // and absorb them into the old gen.  Returns true if eden was emptied.
  65   static bool absorb_live_data_from_eden(PSAdaptiveSizePolicy* size_policy,
  66                                          PSYoungGen* young_gen,
  67                                          PSOldGen* old_gen);
  68 
  69   // Reset time since last full gc
  70   static void reset_millis_since_last_gc();
  71 
  72  public:
  73   static void invoke(bool clear_all_softrefs);
  74   static void invoke_no_policy(bool clear_all_softrefs);
  75 
  76   static void initialize();
  77 
  78   // Public accessors
  79   static elapsedTimer* accumulated_time() { return &_accumulated_time; }
  80   static unsigned int total_invocations() { return _total_invocations; }
  81   static CollectorCounters* counters()    { return _counters; }
  82 
  83   // Time since last full gc (in milliseconds)
  84   static jlong millis_since_last_gc();
  85 };