1 /* 2 * Copyright (c) 2001, 2012, 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 #ifndef SHARE_VM_MEMORY_GENOOPCLOSURES_INLINE_HPP 26 #define SHARE_VM_MEMORY_GENOOPCLOSURES_INLINE_HPP 27 28 #include "memory/cardTableRS.hpp" 29 #include "memory/defNewGeneration.hpp" 30 #include "memory/genCollectedHeap.hpp" 31 #include "memory/genOopClosures.hpp" 32 #include "memory/genRemSet.hpp" 33 #include "memory/generation.hpp" 34 #include "memory/sharedHeap.hpp" 35 #include "memory/space.hpp" 36 37 inline OopsInGenClosure::OopsInGenClosure(Generation* gen) : 38 ExtendedOopClosure(gen->ref_processor()), _orig_gen(gen), _rs(NULL) { 39 set_generation(gen); 40 } 41 42 inline void OopsInGenClosure::set_generation(Generation* gen) { 43 _gen = gen; 44 _gen_boundary = _gen->reserved().start(); 45 // Barrier set for the heap, must be set after heap is initialized 46 if (_rs == NULL) { 47 GenRemSet* rs = GenCollectedHeap::heap()->rem_set(); 48 _rs = (CardTableRS*)rs; 49 } 50 } 51 52 template <class T> inline void OopsInGenClosure::do_barrier(T* p) { 53 assert(generation()->is_in_reserved(p), "expected ref in generation"); 54 T heap_oop = oopDesc::load_heap_oop(p); 55 assert(!oopDesc::is_null(heap_oop), "expected non-null oop"); 56 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); 57 // If p points to a younger generation, mark the card. 58 if ((HeapWord*)obj < _gen_boundary) { 59 _rs->inline_write_ref_field_gc(p, obj); 60 } 61 } 62 63 template <class T> inline void OopsInGenClosure::par_do_barrier(T* p) { 64 assert(generation()->is_in_reserved(p), "expected ref in generation"); 65 T heap_oop = oopDesc::load_heap_oop(p); 66 assert(!oopDesc::is_null(heap_oop), "expected non-null oop"); 67 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); 68 // If p points to a younger generation, mark the card. 69 if ((HeapWord*)obj < gen_boundary()) { 70 rs()->write_ref_field_gc_par(p, obj); 71 } 72 } 73 74 inline void OopsInKlassOrGenClosure::do_klass_barrier() { 75 assert(_scanned_klass != NULL, "Must be"); 76 _scanned_klass->record_modified_oops(); 77 } 78 79 // NOTE! Any changes made here should also be made 80 // in FastScanClosure::do_oop_work() 81 template <class T> inline void ScanClosure::do_oop_work(T* p) { 82 T heap_oop = oopDesc::load_heap_oop(p); 83 // Should we copy the obj? 84 if (!oopDesc::is_null(heap_oop)) { 85 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); 86 if ((HeapWord*)obj < _boundary) { 87 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?"); 88 oop new_obj = obj->is_forwarded() ? obj->forwardee() 89 : _g->copy_to_survivor_space(obj); 90 oopDesc::encode_store_heap_oop_not_null(p, new_obj); 91 } 92 93 if (is_scanning_a_klass()) { 94 do_klass_barrier(); 95 } else if (_gc_barrier) { 96 // Now call parent closure 97 do_barrier(p); 98 } 99 } 100 } 101 102 inline void ScanClosure::do_oop_nv(oop* p) { ScanClosure::do_oop_work(p); } 103 inline void ScanClosure::do_oop_nv(narrowOop* p) { ScanClosure::do_oop_work(p); } 104 105 // NOTE! Any changes made here should also be made 106 // in ScanClosure::do_oop_work() 107 template <class T> inline void FastScanClosure::do_oop_work(T* p) { 108 T heap_oop = oopDesc::load_heap_oop(p); 109 // Should we copy the obj? 110 if (!oopDesc::is_null(heap_oop)) { 111 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); 112 if ((HeapWord*)obj < _boundary) { 113 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?"); 114 oop new_obj = obj->is_forwarded() ? obj->forwardee() 115 : _g->copy_to_survivor_space(obj); 116 oopDesc::encode_store_heap_oop_not_null(p, new_obj); 117 if (is_scanning_a_klass()) { 118 do_klass_barrier(); 119 } else if (_gc_barrier) { 120 // Now call parent closure 121 do_barrier(p); 122 } 123 } 124 } 125 } 126 127 inline void FastScanClosure::do_oop_nv(oop* p) { FastScanClosure::do_oop_work(p); } 128 inline void FastScanClosure::do_oop_nv(narrowOop* p) { FastScanClosure::do_oop_work(p); } 129 130 // Note similarity to ScanClosure; the difference is that 131 // the barrier set is taken care of outside this closure. 132 template <class T> inline void ScanWeakRefClosure::do_oop_work(T* p) { 133 assert(!oopDesc::is_null(*p), "null weak reference?"); 134 oop obj = oopDesc::load_decode_heap_oop_not_null(p); 135 // weak references are sometimes scanned twice; must check 136 // that to-space doesn't already contain this object 137 if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) { 138 oop new_obj = obj->is_forwarded() ? obj->forwardee() 139 : _g->copy_to_survivor_space(obj); 140 oopDesc::encode_store_heap_oop_not_null(p, new_obj); 141 } 142 } 143 144 inline void ScanWeakRefClosure::do_oop_nv(oop* p) { ScanWeakRefClosure::do_oop_work(p); } 145 inline void ScanWeakRefClosure::do_oop_nv(narrowOop* p) { ScanWeakRefClosure::do_oop_work(p); } 146 147 #endif // SHARE_VM_MEMORY_GENOOPCLOSURES_INLINE_HPP