1 /* 2 * Copyright (c) 2001, 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 25 #ifndef SHARE_VM_GC_SHARED_GENOOPCLOSURES_INLINE_HPP 26 #define SHARE_VM_GC_SHARED_GENOOPCLOSURES_INLINE_HPP 27 28 #include "gc/serial/defNewGeneration.hpp" 29 #include "gc/shared/cardTableRS.hpp" 30 #include "gc/shared/genCollectedHeap.hpp" 31 #include "gc/shared/genOopClosures.hpp" 32 #include "gc/shared/generation.hpp" 33 #include "gc/shared/space.hpp" 34 35 inline OopsInGenClosure::OopsInGenClosure(Generation* gen) : 36 ExtendedOopClosure(gen->ref_processor()), _orig_gen(gen), _rs(NULL) { 37 set_generation(gen); 38 } 39 40 inline void OopsInGenClosure::set_generation(Generation* gen) { 41 _gen = gen; 42 _gen_boundary = _gen->reserved().start(); 43 // Barrier set for the heap, must be set after heap is initialized 44 if (_rs == NULL) { 45 _rs = GenCollectedHeap::heap()->rem_set(); 46 } 47 } 48 49 template <class T> inline void OopsInGenClosure::do_barrier(T* p) { 50 assert(generation()->is_in_reserved(p), "expected ref in generation"); 51 T heap_oop = oopDesc::load_heap_oop(p); 52 assert(!oopDesc::is_null(heap_oop), "expected non-null oop"); 53 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); 54 // If p points to a younger generation, mark the card. 55 if ((HeapWord*)obj < _gen_boundary) { 56 _rs->inline_write_ref_field_gc(p, obj); 57 } 58 } 59 60 template <class T> inline void OopsInGenClosure::par_do_barrier(T* p) { 61 assert(generation()->is_in_reserved(p), "expected ref in generation"); 62 T heap_oop = oopDesc::load_heap_oop(p); 63 assert(!oopDesc::is_null(heap_oop), "expected non-null oop"); 64 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); 65 // If p points to a younger generation, mark the card. 66 if ((HeapWord*)obj < gen_boundary()) { 67 rs()->write_ref_field_gc_par(p, obj); 68 } 69 } 70 71 inline void OopsInClassLoaderDataOrGenClosure::do_cld_barrier() { 72 assert(_scanned_cld != NULL, "Must be"); 73 if (!_scanned_cld->has_modified_oops()) { 74 _scanned_cld->record_modified_oops(); 75 } 76 } 77 78 // NOTE! Any changes made here should also be made 79 // in FastScanClosure::do_oop_work() 80 template <class T> inline void ScanClosure::do_oop_work(T* p) { 81 T heap_oop = oopDesc::load_heap_oop(p); 82 // Should we copy the obj? 83 if (!oopDesc::is_null(heap_oop)) { 84 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); 85 if ((HeapWord*)obj < _boundary) { 86 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?"); 87 oop new_obj = obj->is_forwarded() ? obj->forwardee() 88 : _g->copy_to_survivor_space(obj); 89 oopDesc::encode_store_heap_oop_not_null(p, new_obj); 90 } 91 92 if (is_scanning_a_cld()) { 93 do_cld_barrier(); 94 } else if (_gc_barrier) { 95 // Now call parent closure 96 do_barrier(p); 97 } 98 } 99 } 100 101 inline void ScanClosure::do_oop_nv(oop* p) { ScanClosure::do_oop_work(p); } 102 inline void ScanClosure::do_oop_nv(narrowOop* p) { ScanClosure::do_oop_work(p); } 103 104 // NOTE! Any changes made here should also be made 105 // in ScanClosure::do_oop_work() 106 template <class T> inline void FastScanClosure::do_oop_work(T* p) { 107 T heap_oop = oopDesc::load_heap_oop(p); 108 // Should we copy the obj? 109 if (!oopDesc::is_null(heap_oop)) { 110 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); 111 if ((HeapWord*)obj < _boundary) { 112 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?"); 113 oop new_obj = obj->is_forwarded() ? obj->forwardee() 114 : _g->copy_to_survivor_space(obj); 115 oopDesc::encode_store_heap_oop_not_null(p, new_obj); 116 if (is_scanning_a_cld()) { 117 do_cld_barrier(); 118 } else if (_gc_barrier) { 119 // Now call parent closure 120 do_barrier(p); 121 } 122 } 123 } 124 } 125 126 inline void FastScanClosure::do_oop_nv(oop* p) { FastScanClosure::do_oop_work(p); } 127 inline void FastScanClosure::do_oop_nv(narrowOop* p) { FastScanClosure::do_oop_work(p); } 128 129 template <class T> void FilteringClosure::do_oop_work(T* p) { 130 T heap_oop = oopDesc::load_heap_oop(p); 131 if (!oopDesc::is_null(heap_oop)) { 132 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); 133 if ((HeapWord*)obj < _boundary) { 134 _cl->do_oop(p); 135 } 136 } 137 } 138 139 void FilteringClosure::do_oop_nv(oop* p) { FilteringClosure::do_oop_work(p); } 140 void FilteringClosure::do_oop_nv(narrowOop* p) { FilteringClosure::do_oop_work(p); } 141 142 // Note similarity to ScanClosure; the difference is that 143 // the barrier set is taken care of outside this closure. 144 template <class T> inline void ScanWeakRefClosure::do_oop_work(T* p) { 145 assert(!oopDesc::is_null(*p), "null weak reference?"); 146 oop obj = oopDesc::load_decode_heap_oop_not_null(p); 147 // weak references are sometimes scanned twice; must check 148 // that to-space doesn't already contain this object 149 if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) { 150 oop new_obj = obj->is_forwarded() ? obj->forwardee() 151 : _g->copy_to_survivor_space(obj); 152 oopDesc::encode_store_heap_oop_not_null(p, new_obj); 153 } 154 } 155 156 inline void ScanWeakRefClosure::do_oop_nv(oop* p) { ScanWeakRefClosure::do_oop_work(p); } 157 inline void ScanWeakRefClosure::do_oop_nv(narrowOop* p) { ScanWeakRefClosure::do_oop_work(p); } 158 159 #endif // SHARE_VM_GC_SHARED_GENOOPCLOSURES_INLINE_HPP