Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright 2005-2006 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.

  *

  */

 // The VM_CMS_Operation is slightly different from

 // a VM_GC_Operation -- and would not have subclassed easily

 // to VM_GC_Operation without several changes to VM_GC_Operation.

 // To minimize the changes, we have replicated some of the VM_GC_Operation

 // functionality here. We will consolidate that back by doing subclassing

 // as appropriate in Dolphin.

 //

 //  VM_Operation

 //    VM_CMS_Operation

 //    - implements the common portion of work done in support

 //      of CMS' stop-world phases (initial mark and remark).

 //

 //      VM_CMS_Initial_Mark

 //      VM_CMS_Final_Mark

 //

 // Forward decl.

 class CMSCollector;

 class VM_CMS_Operation: public VM_Operation {

  protected:

   CMSCollector*  _collector;                 // associated collector

   bool           _prologue_succeeded;     // whether doit_prologue succeeded

   bool lost_race() const;

   // java.lang.ref.Reference support

   void acquire_pending_list_lock();

   void release_and_notify_pending_list_lock();

  public:

   VM_CMS_Operation(CMSCollector* collector):

     _collector(collector),

     _prologue_succeeded(false) {}

   ~VM_CMS_Operation() {}

   // The legal collector state for executing this CMS op.

   virtual const CMSCollector::CollectorState legal_state() const = 0;

   // Whether the pending list lock needs to be held

   virtual const bool needs_pll() const = 0;

   // Execute operations in the context of the caller,

   // prior to execution of the vm operation itself.

   virtual bool doit_prologue();

   // Execute operations in the context of the caller,

   // following completion of the vm operation.

   virtual void doit_epilogue();

   virtual bool evaluate_at_safepoint() const { return true; }

   virtual bool is_cheap_allocated() const { return false; }

   virtual bool allow_nested_vm_operations() const  { return false; }

   bool prologue_succeeded() const { return _prologue_succeeded; }

   void verify_before_gc();

   void verify_after_gc();

 };

 // VM_CMS_Operation for the initial marking phase of CMS.

 class VM_CMS_Initial_Mark: public VM_CMS_Operation {

  public:

   VM_CMS_Initial_Mark(CMSCollector* _collector) :

     VM_CMS_Operation(_collector) {}

   virtual VMOp_Type type() const { return VMOp_CMS_Initial_Mark; }

   virtual void doit();

   virtual const CMSCollector::CollectorState legal_state() const {

     return CMSCollector::InitialMarking;

   }

   virtual const bool needs_pll() const {

     return false;

   }

 };

 // VM_CMS_Operation for the final remark phase of CMS.

 class VM_CMS_Final_Remark: public VM_CMS_Operation {

  public:

   VM_CMS_Final_Remark(CMSCollector* _collector) :

     VM_CMS_Operation(_collector) {}

   virtual VMOp_Type type() const { return VMOp_CMS_Final_Remark; }

   virtual void doit();

   virtual const CMSCollector::CollectorState legal_state() const {

     return CMSCollector::FinalMarking;

   }

   virtual const bool needs_pll() const {

     return true;

   }

 };

 // VM operation to invoke a concurrent collection of the heap as a

 // GenCollectedHeap heap.

 class VM_GenCollectFullConcurrent: public VM_GC_Operation {

  public:

   VM_GenCollectFullConcurrent(unsigned int gc_count_before,

                               unsigned int full_gc_count_before,

                               GCCause::Cause gc_cause)

     : VM_GC_Operation(gc_count_before, full_gc_count_before, true /* full */) {

     _gc_cause = gc_cause;

     assert(FullGCCount_lock != NULL, "Error");

     assert(UseAsyncConcMarkSweepGC, "Else will hang caller");

   }

   ~VM_GenCollectFullConcurrent() {}

   virtual VMOp_Type type() const { return VMOp_GenCollectFullConcurrent; }

   virtual void doit();

   virtual void doit_epilogue();

   virtual bool is_cheap_allocated() const { return false; }

   virtual bool evaluate_at_safepoint() const;

 };