1 /* 2 * Copyright (c) 2015, 2017, 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_G1_G1ROOTPROCESSOR_HPP 26 #define SHARE_VM_GC_G1_G1ROOTPROCESSOR_HPP 27 28 #include "gc/shared/strongRootsScope.hpp" 29 #include "memory/allocation.hpp" 30 #include "runtime/mutex.hpp" 31 32 class CLDClosure; 33 class CodeBlobClosure; 34 class G1CollectedHeap; 35 class G1EvacuationRootClosures; 36 class G1GCPhaseTimes; 37 class G1RootClosures; 38 class Monitor; 39 class OopClosure; 40 class SubTasksDone; 41 42 // Scoped object to assist in applying oop, CLD and code blob closures to 43 // root locations. Handles claiming of different root scanning tasks 44 // and takes care of global state for root scanning via a StrongRootsScope. 45 // In the parallel case there is a shared G1RootProcessor object where all 46 // worker thread call the process_roots methods. 47 class G1RootProcessor : public StackObj { 48 G1CollectedHeap* _g1h; 49 SubTasksDone _process_strong_tasks; 50 StrongRootsScope _srs; 51 52 // Used to implement the Thread work barrier. 53 Monitor _lock; 54 volatile jint _n_workers_discovered_strong_classes; 55 56 enum G1H_process_roots_tasks { 57 G1RP_PS_Universe_oops_do, 58 G1RP_PS_JNIHandles_oops_do, 59 G1RP_PS_ObjectSynchronizer_oops_do, 60 G1RP_PS_Management_oops_do, 61 G1RP_PS_SystemDictionary_oops_do, 62 G1RP_PS_ClassLoaderDataGraph_oops_do, 63 G1RP_PS_jvmti_oops_do, 64 G1RP_PS_CodeCache_oops_do, 65 G1RP_PS_aot_oops_do, 66 G1RP_PS_filter_satb_buffers, 67 G1RP_PS_refProcessor_oops_do, 68 G1RP_PS_weakProcessor_oops_do, 69 // Leave this one last. 70 G1RP_PS_NumElements 71 }; 72 73 void worker_has_discovered_all_strong_classes(); 74 void wait_until_all_strong_classes_discovered(); 75 76 void process_all_roots(OopClosure* oops, 77 CLDClosure* clds, 78 CodeBlobClosure* blobs, 79 bool process_string_table); 80 81 void process_java_roots(G1RootClosures* closures, 82 G1GCPhaseTimes* phase_times, 83 uint worker_i); 84 85 void process_vm_roots(G1RootClosures* closures, 86 G1GCPhaseTimes* phase_times, 87 uint worker_i); 88 89 void process_string_table_roots(G1RootClosures* closures, 90 G1GCPhaseTimes* phase_times, 91 uint worker_i); 92 93 void process_code_cache_roots(CodeBlobClosure* code_closure, 94 G1GCPhaseTimes* phase_times, 95 uint worker_i); 96 97 public: 98 G1RootProcessor(G1CollectedHeap* g1h, uint n_workers); 99 100 // Apply closures to the strongly and weakly reachable roots in the system 101 // in a single pass. 102 // Record and report timing measurements for sub phases using the worker_i 103 void evacuate_roots(G1EvacuationRootClosures* closures, uint worker_i); 104 105 // Apply oops, clds and blobs to all strongly reachable roots in the system 106 void process_strong_roots(OopClosure* oops, 107 CLDClosure* clds, 108 CodeBlobClosure* blobs); 109 110 // Apply oops, clds and blobs to strongly and weakly reachable roots in the system 111 void process_all_roots(OopClosure* oops, 112 CLDClosure* clds, 113 CodeBlobClosure* blobs); 114 115 // Apply oops, clds and blobs to strongly and weakly reachable roots in the system, 116 // the only thing different from process_all_roots is that we skip the string table 117 // to avoid keeping every string live when doing class unloading. 118 void process_all_roots_no_string_table(OopClosure* oops, 119 CLDClosure* clds, 120 CodeBlobClosure* blobs); 121 122 // Apply closure to weak roots in the system. Used during the adjust phase 123 // for the Full GC. 124 void process_full_gc_weak_roots(OopClosure* oops); 125 126 // Number of worker threads used by the root processor. 127 uint n_workers() const; 128 }; 129 130 #endif // SHARE_VM_GC_G1_G1ROOTPROCESSOR_HPP