view src/share/vm/gc_implementation/g1/vm_operations_g1.hpp @ 453:c96030fff130

6684579: SoftReference processing can be made more efficient Summary: For current soft-ref clearing policies, we can decide at marking time if a soft-reference will definitely not be cleared, postponing the decision of whether it will definitely be cleared to the final reference processing phase. This can be especially beneficial in the case of concurrent collectors where the marking is usually concurrent but reference processing is usually not. Reviewed-by: jmasa
author ysr
date Thu, 20 Nov 2008 16:56:09 -0800
parents 37f87013dfd8
children 96b229c54d1e
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/*
 * Copyright 2001-2007 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 */

// VM_operations for the G1 collector.
// VM_GC_Operation:
//   - VM_CGC_Operation
//   - VM_G1CollectFull
//   - VM_G1CollectForAllocation
//   - VM_G1IncCollectionPause
//   - VM_G1PopRegionCollectionPause

class VM_G1CollectFull: public VM_GC_Operation {
 private:
 public:
  VM_G1CollectFull(int gc_count_before,
                   GCCause::Cause gc_cause)
    : VM_GC_Operation(gc_count_before)
  {
    _gc_cause = gc_cause;
  }
  ~VM_G1CollectFull() {}
  virtual VMOp_Type type() const { return VMOp_G1CollectFull; }
  virtual void doit();
  virtual const char* name() const {
    return "full garbage-first collection";
  }
};

class VM_G1CollectForAllocation: public VM_GC_Operation {
 private:
  HeapWord*   _res;
  size_t      _size;                       // size of object to be allocated
 public:
  VM_G1CollectForAllocation(size_t size, int gc_count_before)
    : VM_GC_Operation(gc_count_before) {
    _size        = size;
    _res         = NULL;
  }
  ~VM_G1CollectForAllocation()        {}
  virtual VMOp_Type type() const { return VMOp_G1CollectForAllocation; }
  virtual void doit();
  virtual const char* name() const {
    return "garbage-first collection to satisfy allocation";
  }
  HeapWord* result() { return _res; }
};

class VM_G1IncCollectionPause: public VM_GC_Operation {
 public:
  VM_G1IncCollectionPause(int gc_count_before) :
    VM_GC_Operation(gc_count_before) {}
  virtual VMOp_Type type() const { return VMOp_G1IncCollectionPause; }
  virtual void doit();
  virtual const char* name() const {
    return "garbage-first incremental collection pause";
  }
};

class VM_G1PopRegionCollectionPause: public VM_GC_Operation {
  HeapRegion* _pop_region;
 public:
  VM_G1PopRegionCollectionPause(int gc_count_before, HeapRegion* pop_region) :
    VM_GC_Operation(gc_count_before),
    _pop_region(pop_region)
  {}
  virtual VMOp_Type type() const { return VMOp_G1PopRegionCollectionPause; }
  virtual void doit();
  virtual const char* name() const {
    return "garbage-first popular region collection pause";
  }
};

// Concurrent GC stop-the-world operations such as initial and final mark;
// consider sharing these with CMS's counterparts.
class VM_CGC_Operation: public VM_Operation {
  VoidClosure* _cl;
  const char* _printGCMessage;
 public:
  VM_CGC_Operation(VoidClosure* cl, const char *printGCMsg) :
    _cl(cl),
    _printGCMessage(printGCMsg)
    {}

  ~VM_CGC_Operation() {}

  virtual VMOp_Type type() const { return VMOp_CGC_Operation; }
  virtual void doit();
  virtual bool doit_prologue();
  virtual void doit_epilogue();
  virtual const char* name() const {
    return "concurrent gc";
  }
};