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 #include "precompiled.hpp" 25 #include "gc/z/zHeap.hpp" 26 #include "gc/z/zOopClosures.inline.hpp" 27 #include "gc/z/zPage.hpp" 28 #include "gc/z/zRelocate.hpp" 29 #include "gc/z/zRelocationSet.inline.hpp" 30 #include "gc/z/zRootsIterator.hpp" 31 #include "gc/z/zTask.hpp" 32 #include "gc/z/zWorkers.hpp" 33 34 ZRelocate::ZRelocate(ZWorkers* workers) : 35 _workers(workers) {} 36 37 class ZRelocateRootsTask : public ZTask { 38 private: 39 ZRootsIterator _roots; 40 41 public: 42 ZRelocateRootsTask() : 43 ZTask("ZRelocateRootsTask"), 44 _roots() {} 45 46 virtual void work() { 47 // During relocation we need to visit the JVMTI 48 // export weak roots to rehash the JVMTI tag map 49 ZRelocateRootOopClosure cl; 50 _roots.oops_do(&cl, true /* visit_jvmti_weak_export */); 51 } 52 }; 53 54 void ZRelocate::start() { 55 ZRelocateRootsTask task; 56 _workers->run_parallel(&task); 57 } 58 59 class ZRelocateObjectClosure : public ObjectClosure { 60 private: 61 ZPage* const _page; 62 63 public: 64 ZRelocateObjectClosure(ZPage* page) : 65 _page(page) {} 66 67 virtual void do_object(oop o) { 68 _page->relocate_object(ZOop::to_address(o)); 69 } 70 }; 71 72 bool ZRelocate::work(ZRelocationSetParallelIterator* iter) { 73 bool success = true; 74 75 // Relocate pages in the relocation set 76 for (ZPage* page; iter->next(&page);) { 77 // Relocate objects in page 78 ZRelocateObjectClosure cl(page); 79 page->object_iterate(&cl); 80 81 if (ZVerifyForwarding) { 82 page->verify_forwarding(); 83 } 84 85 if (page->is_pinned()) { 86 // Relocation failed, page is now pinned 87 success = false; 88 } else { 89 // Relocation succeeded, release page 90 ZHeap::heap()->release_page(page, true /* reclaimed */); 91 } 92 } 93 94 return success; 95 } 96 97 class ZRelocateTask : public ZTask { 98 private: 99 ZRelocate* const _relocate; 100 ZRelocationSetParallelIterator _iter; 101 bool _failed; 102 103 public: 104 ZRelocateTask(ZRelocate* relocate, ZRelocationSet* relocation_set) : 105 ZTask("ZRelocateTask"), 106 _relocate(relocate), 107 _iter(relocation_set), 108 _failed(false) {} 109 110 virtual void work() { 111 if (!_relocate->work(&_iter)) { 112 _failed = true; 113 } 114 } 115 116 bool failed() const { 117 return _failed; 118 } 119 }; 120 121 bool ZRelocate::relocate(ZRelocationSet* relocation_set) { 122 ZRelocateTask task(this, relocation_set); 123 _workers->run_concurrent(&task); 124 return !task.failed(); 125 }