1 /* 2 * Copyright (c) 2014, 2018, 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 #include "precompiled.hpp" 26 #include "classfile/classLoaderData.hpp" 27 #include "classfile/systemDictionary.hpp" 28 #include "jfr/leakprofiler/chains/edgeQueue.hpp" 29 #include "jfr/leakprofiler/chains/rootSetClosure.hpp" 30 #include "jfr/leakprofiler/utilities/saveRestore.hpp" 31 #include "jfr/leakprofiler/utilities/unifiedOop.hpp" 32 #include "memory/universe.hpp" 33 #include "prims/jvmtiExport.hpp" 34 #include "runtime/jniHandles.hpp" 35 #include "runtime/synchronizer.hpp" 36 #include "runtime/thread.hpp" 37 #include "services/management.hpp" 38 #include "utilities/align.hpp" 39 40 RootSetClosure::RootSetClosure(EdgeQueue* edge_queue) : 41 _edge_queue(edge_queue) { 42 } 43 44 void RootSetClosure::do_oop(oop* ref) { 45 assert(ref != NULL, "invariant"); 46 // We discard unaligned root references because 47 // our reference tagging scheme will use 48 // the lowest bit in a represented reference 49 // to indicate the reference is narrow. 50 // It is mainly roots delivered via nmethods::do_oops() 51 // that come in unaligned. It should be ok to duck these 52 // since they are supposedly weak. 53 if (!is_aligned(ref, HeapWordSize)) { 54 return; 55 } 56 57 assert(is_aligned(ref, HeapWordSize), "invariant"); 58 const oop pointee = *ref; 59 if (pointee != NULL) { 60 closure_impl(ref, pointee); 61 } 62 } 63 64 void RootSetClosure::do_oop(narrowOop* ref) { 65 assert(ref != NULL, "invariant"); 66 assert(is_aligned(ref, sizeof(narrowOop)), "invariant"); 67 const oop pointee = oopDesc::load_decode_heap_oop(ref); 68 if (pointee != NULL) { 69 closure_impl(UnifiedOop::encode(ref), pointee); 70 } 71 } 72 73 void RootSetClosure::closure_impl(const oop* reference, const oop pointee) { 74 if (!_edge_queue->is_full()) { 75 _edge_queue->add(NULL, reference); 76 } 77 } 78 79 void RootSetClosure::add_to_queue(EdgeQueue* edge_queue) { 80 RootSetClosure rs(edge_queue); 81 process_roots(&rs); 82 } 83 84 class RootSetClosureMarkScope : public MarkingCodeBlobClosure::MarkScope { 85 }; 86 87 void RootSetClosure::process_roots(OopClosure* closure) { 88 SaveRestoreCLDClaimBits save_restore_cld_claim_bits; 89 RootSetClosureMarkScope mark_scope; 90 91 CLDToOopClosure cldt_closure(closure); 92 ClassLoaderDataGraph::always_strong_cld_do(&cldt_closure); 93 CodeBlobToOopClosure blobs(closure, false); 94 Threads::oops_do(closure, NULL, &blobs); // XXX set CLDClosure to NULL 95 ObjectSynchronizer::oops_do(closure); 96 Universe::oops_do(closure); 97 JNIHandles::oops_do(closure); 98 JvmtiExport::oops_do(closure); 99 SystemDictionary::oops_do(closure); 100 Management::oops_do(closure); 101 StringTable::oops_do(closure); 102 }