1 /* 2 * Copyright (c) 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_G1_ROOTPROCESSOR_HPP 26 #define SHARE_VM_GC_IMPLEMENTATION_G1_ROOTPROCESSOR_HPP 27 28 #include "memory/allocation.hpp" 29 #include "memory/sharedHeap.hpp" 30 #include "runtime/mutex.hpp" 31 32 class CLDClosure; 33 class CodeBlobClosure; 34 class G1CollectedHeap; 35 class G1ParPushHeapRSClosure; 36 class Monitor; 37 class OopClosure; 38 class SubTasksDone; 39 40 // Scoped object to assist in applying oop, CLD and code blob closures to 41 // root locations. Handles claiming of different root scanning tasks 42 // and takes care of global state for root scanning via a StrongRootsScope. 43 // In the parallel case there is a shared G1RootProcessor object where all 44 // worker thread call the process_roots methods. 45 class G1RootProcessor : public StackObj { 46 G1CollectedHeap* _g1h; 47 SubTasksDone* _process_strong_tasks; 48 SharedHeap::StrongRootsScope _srs; 49 50 // Used to implement the Thread work barrier. 51 Monitor _lock; 52 volatile jint _n_workers_discovered_strong_classes; 53 const bool _trace_metadata; 54 55 enum G1H_process_roots_tasks { 56 G1RP_PS_Universe_oops_do, 57 G1RP_PS_JNIHandles_oops_do, 58 G1RP_PS_ObjectSynchronizer_oops_do, 59 G1RP_PS_FlatProfiler_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_filter_satb_buffers, 66 G1RP_PS_refProcessor_oops_do, 67 // Leave this one last. 68 G1RP_PS_NumElements 69 }; 70 71 void worker_has_discovered_all_strong_classes(); 72 void wait_until_all_strong_classes_discovered(); 73 74 void process_java_roots(OopClosure* scan_non_heap_roots, 75 CLDClosure* thread_stack_clds, 76 CLDClosure* scan_strong_clds, 77 CLDClosure* scan_weak_clds, 78 CodeBlobClosure* scan_strong_code); 79 80 void process_vm_roots(OopClosure* scan_non_heap_roots, 81 OopClosure* scan_non_heap_weak_roots); 82 83 public: 84 G1RootProcessor(G1CollectedHeap* g1h, bool trace_metadata); 85 86 // Apply closures to the strongly and weakly reachable roots in the system 87 // in a single pass. 88 // Record and report timing measurements for sub phases using the worker_i 89 void evacuate_roots(OopClosure* scan_non_heap_roots, 90 OopClosure* scan_non_heap_weak_roots, 91 CLDClosure* scan_strong_clds, 92 CLDClosure* scan_weak_clds, 93 uint worker_i); 94 95 // Apply oops, clds and blobs to all strongly reachable roots in the system 96 void process_strong_roots(OopClosure* oops, 97 CLDClosure* clds, 98 CodeBlobClosure* blobs); 99 100 // Apply oops, clds and blobs to strongly and weakly reachable roots in the system 101 void process_all_roots(OopClosure* oops, 102 CLDClosure* clds, 103 CodeBlobClosure* blobs); 104 105 // Apply scan_rs to all locations in the union of the remembered sets for all 106 // regions in the collection set 107 // (having done "set_region" to indicate the region in which the root resides), 108 void scan_remembered_sets(G1ParPushHeapRSClosure* scan_rs, 109 OopClosure* scan_non_heap_weak_roots, 110 uint worker_i); 111 112 // Inform the root processor about the number of worker threads 113 void set_num_workers(int active_workers); 114 }; 115 116 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_ROOTPROCESSOR_HPP