1 /* 2 * Copyright (c) 2013, 2019, Red Hat, Inc. All rights reserved. 3 * 4 * This code is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 only, as 6 * published by the Free Software Foundation. 7 * 8 * This code is distributed in the hope that it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 11 * version 2 for more details (a copy is included in the LICENSE file that 12 * accompanied this code). 13 * 14 * You should have received a copy of the GNU General Public License version 15 * 2 along with this work; if not, write to the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 17 * 18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 19 * or visit www.oracle.com if you need additional information or have any 20 * questions. 21 * 22 */ 23 24 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHBARRIERSETCLONE_INLINE_HPP 25 #define SHARE_GC_SHENANDOAH_SHENANDOAHBARRIERSETCLONE_INLINE_HPP 26 27 #include "gc/shenandoah/shenandoahBarrierSet.inline.hpp" 28 #include "gc/shenandoah/shenandoahCollectionSet.inline.hpp" 29 #include "gc/shenandoah/shenandoahEvacOOMHandler.hpp" 30 #include "gc/shenandoah/shenandoahHeap.inline.hpp" 31 #include "memory/iterator.hpp" 32 #include "oops/access.hpp" 33 #include "oops/compressedOops.hpp" 34 35 template <bool EVAC, bool ENQUEUE> 36 class ShenandoahUpdateRefsForOopClosure: public BasicOopIterateClosure { 37 private: 38 ShenandoahHeap* const _heap; 39 ShenandoahBarrierSet* const _bs; 40 const ShenandoahCollectionSet* const _cset; 41 Thread* const _thread; 42 43 template <class T> 44 inline void do_oop_work(T* p) { 45 T o = RawAccess<>::oop_load(p); 46 if (!CompressedOops::is_null(o)) { 47 oop obj = CompressedOops::decode_not_null(o); 48 if (_cset->is_in((HeapWord *)obj)) { 49 oop fwd = _bs->resolve_forwarded_not_null(obj); 50 if (EVAC && obj == fwd) { 51 fwd = _heap->evacuate_object(obj, _thread); 52 } 53 if (ENQUEUE) { 54 _bs->enqueue(fwd); 55 } 56 assert(obj != fwd || _heap->cancelled_gc(), "must be forwarded"); 57 ShenandoahHeap::cas_oop(fwd, p, o); 58 } 59 60 } 61 } 62 public: 63 ShenandoahUpdateRefsForOopClosure() : 64 _heap(ShenandoahHeap::heap()), 65 _bs(ShenandoahBarrierSet::barrier_set()), 66 _cset(_heap->collection_set()), 67 _thread(Thread::current()) { 68 } 69 70 virtual void do_oop(oop* p) { do_oop_work(p); } 71 virtual void do_oop(narrowOop* p) { do_oop_work(p); } 72 }; 73 74 void ShenandoahBarrierSet::clone_barrier(oop obj) { 75 assert(ShenandoahCloneBarrier, "only get here with clone barriers enabled"); 76 if (!_heap->has_forwarded_objects()) return; 77 78 // This is called for cloning an object (see jvm.cpp) after the clone 79 // has been made. We are not interested in any 'previous value' because 80 // it would be NULL in any case. But we *are* interested in any oop* 81 // that potentially need to be updated. 82 83 shenandoah_assert_correct(NULL, obj); 84 if (_heap->is_evacuation_in_progress()) { 85 ShenandoahEvacOOMScope evac_scope; 86 ShenandoahUpdateRefsForOopClosure</* evac = */ true, /* enqueue */ false> cl; 87 obj->oop_iterate(&cl); 88 } else if (_heap->is_concurrent_traversal_in_progress()) { 89 ShenandoahEvacOOMScope evac_scope; 90 ShenandoahUpdateRefsForOopClosure</* evac = */ true, /* enqueue */ true> cl; 91 obj->oop_iterate(&cl); 92 } else { 93 ShenandoahUpdateRefsForOopClosure</* evac = */ false, /* enqueue */ false> cl; 94 obj->oop_iterate(&cl); 95 } 96 } 97 98 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHBARRIERSETCLONE_INLINE_HPP