1 /* 2 * Copyright (c) 2005, 2015, 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 #ifndef SHARE_VM_GC_CMS_VMCMSOPERATIONS_HPP 26 #define SHARE_VM_GC_CMS_VMCMSOPERATIONS_HPP 27 28 #include "gc/cms/concurrentMarkSweepGeneration.hpp" 29 #include "gc/shared/gcCause.hpp" 30 #include "gc/shared/gcId.hpp" 31 #include "gc/shared/vmGCOperations.hpp" 32 #include "runtime/vm_operations.hpp" 33 34 // The VM_CMS_Operation is slightly different from 35 // a VM_GC_Operation -- and would not have subclassed easily 36 // to VM_GC_Operation without several changes to VM_GC_Operation. 37 // To minimize the changes, we have replicated some of the VM_GC_Operation 38 // functionality here. We will consolidate that back by doing subclassing 39 // as appropriate in Dolphin. 40 // 41 // VM_Operation 42 // VM_CMS_Operation 43 // - implements the common portion of work done in support 44 // of CMS' stop-world phases (initial mark and remark). 45 // 46 // VM_CMS_Initial_Mark 47 // VM_CMS_Final_Mark 48 // 49 50 // Forward decl. 51 class CMSCollector; 52 53 class VM_CMS_Operation: public VM_Operation { 54 protected: 55 CMSCollector* _collector; // associated collector 56 bool _prologue_succeeded; // whether doit_prologue succeeded 57 uint _gc_id; 58 59 bool lost_race() const; 60 61 // java.lang.ref.Reference support 62 void acquire_pending_list_lock(); 63 void release_and_notify_pending_list_lock(); 64 65 public: 66 VM_CMS_Operation(CMSCollector* collector): 67 _collector(collector), 68 _prologue_succeeded(false), 69 _gc_id(GCId::current()) {} 70 ~VM_CMS_Operation() {} 71 72 // The legal collector state for executing this CMS op. 73 virtual const CMSCollector::CollectorState legal_state() const = 0; 74 75 // Whether the pending list lock needs to be held 76 virtual const bool needs_pll() const = 0; 77 78 // Execute operations in the context of the caller, 79 // prior to execution of the vm operation itself. 80 virtual bool doit_prologue(); 81 // Execute operations in the context of the caller, 82 // following completion of the vm operation. 83 virtual void doit_epilogue(); 84 85 virtual bool evaluate_at_safepoint() const { return true; } 86 virtual bool is_cheap_allocated() const { return false; } 87 virtual bool allow_nested_vm_operations() const { return false; } 88 bool prologue_succeeded() const { return _prologue_succeeded; } 89 90 void verify_before_gc(); 91 void verify_after_gc(); 92 }; 93 94 95 // VM_CMS_Operation for the initial marking phase of CMS. 96 class VM_CMS_Initial_Mark: public VM_CMS_Operation { 97 public: 98 VM_CMS_Initial_Mark(CMSCollector* _collector) : 99 VM_CMS_Operation(_collector) {} 100 101 virtual VMOp_Type type() const { return VMOp_CMS_Initial_Mark; } 102 virtual void doit(); 103 104 virtual const CMSCollector::CollectorState legal_state() const { 105 return CMSCollector::InitialMarking; 106 } 107 108 virtual const bool needs_pll() const { 109 return false; 110 } 111 }; 112 113 // VM_CMS_Operation for the final remark phase of CMS. 114 class VM_CMS_Final_Remark: public VM_CMS_Operation { 115 public: 116 VM_CMS_Final_Remark(CMSCollector* _collector) : 117 VM_CMS_Operation(_collector) {} 118 virtual VMOp_Type type() const { return VMOp_CMS_Final_Remark; } 119 virtual void doit(); 120 121 virtual const CMSCollector::CollectorState legal_state() const { 122 return CMSCollector::FinalMarking; 123 } 124 125 virtual const bool needs_pll() const { 126 return true; 127 } 128 }; 129 130 131 // VM operation to invoke a concurrent collection of the heap as a 132 // GenCollectedHeap heap. 133 class VM_GenCollectFullConcurrent: public VM_GC_Operation { 134 public: 135 VM_GenCollectFullConcurrent(uint gc_count_before, 136 uint full_gc_count_before, 137 GCCause::Cause gc_cause) 138 : VM_GC_Operation(gc_count_before, gc_cause, full_gc_count_before, true /* full */) 139 { 140 assert(FullGCCount_lock != NULL, "Error"); 141 } 142 ~VM_GenCollectFullConcurrent() {} 143 virtual VMOp_Type type() const { return VMOp_GenCollectFullConcurrent; } 144 virtual void doit(); 145 virtual void doit_epilogue(); 146 virtual bool is_cheap_allocated() const { return false; } 147 virtual bool evaluate_at_safepoint() const; 148 }; 149 150 #endif // SHARE_VM_GC_CMS_VMCMSOPERATIONS_HPP