1 /* 2 * Copyright (c) 2014, 2019, 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/synchronizer.hpp" 35 #include "runtime/thread.hpp" 36 #include "services/management.hpp" 37 #include "jfr/utilities/align.hpp" 38 39 RootSetClosure::RootSetClosure(EdgeQueue* edge_queue) : 40 _edge_queue(edge_queue) { 41 } 42 43 void RootSetClosure::do_oop(oop* ref) { 44 assert(ref != NULL, "invariant"); 45 // We discard unaligned root references because 46 // our reference tagging scheme will use 47 // the lowest bit in a represented reference 48 // to indicate the reference is narrow. 49 // It is mainly roots delivered via nmethods::do_oops() 50 // that come in unaligned. It should be ok to duck these 51 // since they are supposedly weak. 52 if (!is_aligned(ref, HeapWordSize)) { 53 return; 54 } 55 56 assert(is_aligned(ref, HeapWordSize), "invariant"); 57 const oop pointee = *ref; 58 if (pointee != NULL) { 59 closure_impl(ref, pointee); 60 } 61 } 62 63 void RootSetClosure::do_oop(narrowOop* ref) { 64 assert(ref != NULL, "invariant"); 65 assert(is_aligned(ref, sizeof(narrowOop)), "invariant"); 66 const oop pointee = oopDesc::load_decode_heap_oop(ref); 67 if (pointee != NULL) { 68 closure_impl(UnifiedOop::encode(ref), pointee); 69 } 70 } 71 72 void RootSetClosure::closure_impl(const oop* reference, const oop pointee) { 73 if (!_edge_queue->is_full()) { 74 _edge_queue->add(NULL, reference); 75 } 76 } 77 78 void RootSetClosure::add_to_queue(EdgeQueue* edge_queue) { 79 RootSetClosure rs(edge_queue); 80 process_roots(&rs); 81 } 82 83 class RootSetClosureMarkScope : public MarkingCodeBlobClosure::MarkScope { 84 }; 85 86 void RootSetClosure::process_roots(OopClosure* closure) { 87 SaveRestoreCLDClaimBits save_restore_cld_claim_bits; 88 RootSetClosureMarkScope mark_scope; 89 90 CLDToOopClosure cldt_closure(closure); 91 ClassLoaderDataGraph::always_strong_cld_do(&cldt_closure); 92 CodeBlobToOopClosure blobs(closure, false); 93 Threads::oops_do(closure, &cldt_closure, &blobs); 94 ObjectSynchronizer::oops_do(closure); 95 Universe::oops_do(closure); 96 JNIHandles::oops_do(closure); 97 JvmtiExport::oops_do(closure); 98 SystemDictionary::always_strong_oops_do(closure); 99 Management::oops_do(closure); 100 StringTable::oops_do(closure); 101 }