1 /* 2 * Copyright (c) 2013, 2019, Red Hat, Inc. 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_GC_SHENANDOAH_SHENANDOAHBARRIERSETCLONE_INLINE_HPP 26 #define SHARE_GC_SHENANDOAH_SHENANDOAHBARRIERSETCLONE_INLINE_HPP 27 28 #include "gc/shenandoah/shenandoahBarrierSet.inline.hpp" 29 #include "gc/shenandoah/shenandoahCollectionSet.inline.hpp" 30 #include "gc/shenandoah/shenandoahEvacOOMHandler.hpp" 31 #include "gc/shenandoah/shenandoahHeap.inline.hpp" 32 #include "memory/iterator.hpp" 33 #include "oops/access.hpp" 34 #include "oops/compressedOops.hpp" 35 36 template <bool EVAC, bool ENQUEUE> 37 class ShenandoahUpdateRefsForOopClosure: public BasicOopIterateClosure { 38 private: 39 ShenandoahHeap* const _heap; 40 ShenandoahBarrierSet* const _bs; 41 const ShenandoahCollectionSet* const _cset; 42 Thread* const _thread; 43 44 template <class T> 45 inline void do_oop_work(T* p) { 46 T o = RawAccess<>::oop_load(p); 47 if (!CompressedOops::is_null(o)) { 48 oop obj = CompressedOops::decode_not_null(o); 49 if (_cset->is_in(obj)) { 50 oop fwd = _bs->resolve_forwarded_not_null(obj); 51 if (EVAC && obj == fwd) { 52 fwd = _heap->evacuate_object(obj, _thread); 53 } 54 if (ENQUEUE) { 55 _bs->enqueue(fwd); 56 } 57 assert(obj != fwd || _heap->cancelled_gc(), "must be forwarded"); 58 ShenandoahHeap::cas_oop(fwd, p, o); 59 } 60 61 } 62 } 63 public: 64 ShenandoahUpdateRefsForOopClosure() : 65 _heap(ShenandoahHeap::heap()), 66 _bs(ShenandoahBarrierSet::barrier_set()), 67 _cset(_heap->collection_set()), 68 _thread(Thread::current()) { 69 } 70 71 virtual void do_oop(oop* p) { do_oop_work(p); } 72 virtual void do_oop(narrowOop* p) { do_oop_work(p); } 73 }; 74 75 void ShenandoahBarrierSet::clone_barrier(oop obj) { 76 assert(ShenandoahCloneBarrier, "only get here with clone barriers enabled"); 77 assert(_heap->has_forwarded_objects(), "only when heap is unstable"); 78 79 // This is called for cloning an object (see jvm.cpp) after the clone 80 // has been made. We are not interested in any 'previous value' because 81 // it would be NULL in any case. But we *are* interested in any oop* 82 // that potentially need to be updated. 83 84 shenandoah_assert_correct(NULL, obj); 85 if (skip_bulk_update(cast_from_oop<HeapWord*>(obj))) return; 86 if (_heap->is_evacuation_in_progress()) { 87 ShenandoahEvacOOMScope evac_scope; 88 ShenandoahUpdateRefsForOopClosure</* evac = */ true, /* enqueue */ false> cl; 89 obj->oop_iterate(&cl); 90 } else if (_heap->is_concurrent_traversal_in_progress()) { 91 ShenandoahEvacOOMScope evac_scope; 92 ShenandoahUpdateRefsForOopClosure</* evac = */ true, /* enqueue */ true> cl; 93 obj->oop_iterate(&cl); 94 } else { 95 ShenandoahUpdateRefsForOopClosure</* evac = */ false, /* enqueue */ false> cl; 96 obj->oop_iterate(&cl); 97 } 98 } 99 100 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHBARRIERSETCLONE_INLINE_HPP