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