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