1 /* 2 * Copyright (c) 2007, 2015, 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_CMS_PAROOPCLOSURES_INLINE_HPP 26 #define SHARE_VM_GC_CMS_PAROOPCLOSURES_INLINE_HPP 27 28 #include "gc/cms/parNewGeneration.hpp" 29 #include "gc/cms/parOopClosures.hpp" 30 #include "gc/shared/cardTableRS.hpp" 31 #include "gc/shared/genCollectedHeap.hpp" 32 #include "gc/shared/genOopClosures.inline.hpp" 33 #include "logging/log.hpp" 34 35 template <class T> inline void ParScanWeakRefClosure::do_oop_work(T* p) { 36 assert (!oopDesc::is_null(*p), "null weak reference?"); 37 oop obj = oopDesc::load_decode_heap_oop_not_null(p); 38 // weak references are sometimes scanned twice; must check 39 // that to-space doesn't already contain this object 40 if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) { 41 // we need to ensure that it is copied (see comment in 42 // ParScanClosure::do_oop_work). 43 Klass* objK = obj->klass(); 44 markOop m = obj->mark(); 45 oop new_obj; 46 if (m->is_marked()) { // Contains forwarding pointer. 47 new_obj = ParNewGeneration::real_forwardee(obj); 48 } else { 49 size_t obj_sz = obj->size_given_klass(objK); 50 new_obj = ((ParNewGeneration*)_g)->copy_to_survivor_space(_par_scan_state, 51 obj, obj_sz, m); 52 } 53 oopDesc::encode_store_heap_oop_not_null(p, new_obj); 54 } 55 } 56 57 inline void ParScanWeakRefClosure::do_oop_nv(oop* p) { ParScanWeakRefClosure::do_oop_work(p); } 58 inline void ParScanWeakRefClosure::do_oop_nv(narrowOop* p) { ParScanWeakRefClosure::do_oop_work(p); } 59 60 template <class T> inline void ParScanClosure::par_do_barrier(T* p) { 61 assert(generation()->is_in_reserved(p), "expected ref in generation"); 62 assert(!oopDesc::is_null(*p), "expected non-null object"); 63 oop obj = oopDesc::load_decode_heap_oop_not_null(p); 64 // If p points to a younger generation, mark the card. 65 if ((HeapWord*)obj < gen_boundary()) { 66 rs()->write_ref_field_gc_par(p, obj); 67 } 68 } 69 70 template <class T> 71 inline void ParScanClosure::do_oop_work(T* p, 72 bool gc_barrier, 73 bool root_scan) { 74 assert((!GenCollectedHeap::heap()->is_in_reserved(p) || 75 generation()->is_in_reserved(p)) 76 && (GenCollectedHeap::heap()->is_young_gen(generation()) || gc_barrier), 77 "The gen must be right, and we must be doing the barrier " 78 "in older generations."); 79 T heap_oop = oopDesc::load_heap_oop(p); 80 if (!oopDesc::is_null(heap_oop)) { 81 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); 82 if ((HeapWord*)obj < _boundary) { 83 #ifndef PRODUCT 84 if (_g->to()->is_in_reserved(obj)) { 85 tty->print_cr("Scanning field (" PTR_FORMAT ") twice?", p2i(p)); 86 GenCollectedHeap* gch = GenCollectedHeap::heap(); 87 Space* sp = gch->space_containing(p); 88 oop obj = oop(sp->block_start(p)); 89 assert((HeapWord*)obj < (HeapWord*)p, "Error"); 90 tty->print_cr("Object: " PTR_FORMAT, p2i((void *)obj)); 91 tty->print_cr("-------"); 92 obj->print(); 93 tty->print_cr("-----"); 94 tty->print_cr("Heap:"); 95 tty->print_cr("-----"); 96 gch->print(); 97 ShouldNotReachHere(); 98 } 99 #endif 100 // OK, we need to ensure that it is copied. 101 // We read the klass and mark in this order, so that we can reliably 102 // get the size of the object: if the mark we read is not a 103 // forwarding pointer, then the klass is valid: the klass is only 104 // overwritten with an overflow next pointer after the object is 105 // forwarded. 106 Klass* objK = obj->klass(); 107 markOop m = obj->mark(); 108 oop new_obj; 109 if (m->is_marked()) { // Contains forwarding pointer. 110 new_obj = ParNewGeneration::real_forwardee(obj); 111 oopDesc::encode_store_heap_oop_not_null(p, new_obj); 112 log_develop(gc, scavenge)("{forwarded %s ( " PTR_FORMAT " ) " PTR_FORMAT " -> " PTR_FORMAT " (%d)}", 113 new_obj->klass()->internal_name(), p2i(p), p2i((void *)obj), p2i((void *)new_obj), new_obj->size()); 114 } else { 115 size_t obj_sz = obj->size_given_klass(objK); 116 new_obj = _g->copy_to_survivor_space(_par_scan_state, obj, obj_sz, m); 117 oopDesc::encode_store_heap_oop_not_null(p, new_obj); 118 if (root_scan) { 119 // This may have pushed an object. If we have a root 120 // category with a lot of roots, can't let the queue get too 121 // full: 122 (void)_par_scan_state->trim_queues(10 * ParallelGCThreads); 123 } 124 } 125 if (is_scanning_a_klass()) { 126 do_klass_barrier(); 127 } else if (gc_barrier) { 128 // Now call parent closure 129 par_do_barrier(p); 130 } 131 } 132 } 133 } 134 135 inline void ParScanWithBarrierClosure::do_oop_nv(oop* p) { ParScanClosure::do_oop_work(p, true, false); } 136 inline void ParScanWithBarrierClosure::do_oop_nv(narrowOop* p) { ParScanClosure::do_oop_work(p, true, false); } 137 138 inline void ParScanWithoutBarrierClosure::do_oop_nv(oop* p) { ParScanClosure::do_oop_work(p, false, false); } 139 inline void ParScanWithoutBarrierClosure::do_oop_nv(narrowOop* p) { ParScanClosure::do_oop_work(p, false, false); } 140 141 #endif // SHARE_VM_GC_CMS_PAROOPCLOSURES_INLINE_HPP