1 /* 2 * Copyright (c) 2005, 2016, 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 public: 62 VM_CMS_Operation(CMSCollector* collector): 63 _collector(collector), 64 _prologue_succeeded(false), 65 _gc_id(GCId::current()) {} 66 ~VM_CMS_Operation() {} 67 68 // The legal collector state for executing this CMS op. 69 virtual const CMSCollector::CollectorState legal_state() const = 0; 70 71 // Whether the pending list lock needs to be held 72 virtual const bool needs_pending_list_lock() const = 0; 73 74 // Execute operations in the context of the caller, 75 // prior to execution of the vm operation itself. 76 virtual bool doit_prologue(); 77 // Execute operations in the context of the caller, 78 // following completion of the vm operation. 79 virtual void doit_epilogue(); 80 81 virtual bool evaluate_at_safepoint() const { return true; } 82 virtual bool is_cheap_allocated() const { return false; } 83 virtual bool allow_nested_vm_operations() const { return false; } 84 bool prologue_succeeded() const { return _prologue_succeeded; } 85 86 void verify_before_gc(); 87 void verify_after_gc(); 88 }; 89 90 91 // VM_CMS_Operation for the initial marking phase of CMS. 92 class VM_CMS_Initial_Mark: public VM_CMS_Operation { 93 public: 94 VM_CMS_Initial_Mark(CMSCollector* _collector) : 95 VM_CMS_Operation(_collector) {} 96 97 virtual VMOp_Type type() const { return VMOp_CMS_Initial_Mark; } 98 virtual void doit(); 99 100 virtual const CMSCollector::CollectorState legal_state() const { 101 return CMSCollector::InitialMarking; 102 } 103 104 virtual const bool needs_pending_list_lock() const { 105 return false; 106 } 107 }; 108 109 // VM_CMS_Operation for the final remark phase of CMS. 110 class VM_CMS_Final_Remark: public VM_CMS_Operation { 111 public: 112 VM_CMS_Final_Remark(CMSCollector* _collector) : 113 VM_CMS_Operation(_collector) {} 114 virtual VMOp_Type type() const { return VMOp_CMS_Final_Remark; } 115 virtual void doit(); 116 117 virtual const CMSCollector::CollectorState legal_state() const { 118 return CMSCollector::FinalMarking; 119 } 120 121 virtual const bool needs_pending_list_lock() const { 122 return true; 123 } 124 }; 125 126 127 // VM operation to invoke a concurrent collection of the heap as a 128 // GenCollectedHeap heap. 129 class VM_GenCollectFullConcurrent: public VM_GC_Operation { 130 public: 131 VM_GenCollectFullConcurrent(uint gc_count_before, 132 uint full_gc_count_before, 133 GCCause::Cause gc_cause) 134 : VM_GC_Operation(gc_count_before, gc_cause, full_gc_count_before, true /* full */) 135 { 136 assert(FullGCCount_lock != NULL, "Error"); 137 } 138 ~VM_GenCollectFullConcurrent() {} 139 virtual VMOp_Type type() const { return VMOp_GenCollectFullConcurrent; } 140 virtual void doit(); 141 virtual void doit_epilogue(); 142 virtual bool is_cheap_allocated() const { return false; } 143 virtual bool evaluate_at_safepoint() const; 144 }; 145 146 #endif // SHARE_VM_GC_CMS_VMCMSOPERATIONS_HPP