1 /*
2 * Copyright (c) 2007, 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.
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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
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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/cmsHeap.hpp"
29 #include "gc/cms/parNewGeneration.hpp"
30 #include "gc/cms/parOopClosures.hpp"
31 #include "gc/shared/cardTableRS.hpp"
32 #include "gc/shared/genOopClosures.inline.hpp"
33 #include "logging/log.hpp"
34 #include "logging/logStream.hpp"
35
36 template <class T> inline void ParScanWeakRefClosure::do_oop_work(T* p) {
37 assert (!oopDesc::is_null(*p), "null weak reference?");
38 oop obj = oopDesc::load_decode_heap_oop_not_null(p);
39 // weak references are sometimes scanned twice; must check
40 // that to-space doesn't already contain this object
41 if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) {
42 // we need to ensure that it is copied (see comment in
43 // ParScanClosure::do_oop_work).
44 Klass* objK = obj->klass();
45 markOop m = obj->mark();
46 oop new_obj;
47 if (m->is_marked()) { // Contains forwarding pointer.
48 new_obj = ParNewGeneration::real_forwardee(obj);
49 } else {
50 size_t obj_sz = obj->size_given_klass(objK);
51 new_obj = ((ParNewGeneration*)_g)->copy_to_survivor_space(_par_scan_state,
52 obj, obj_sz, m);
53 }
54 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
55 }
56 }
57
58 inline void ParScanWeakRefClosure::do_oop_nv(oop* p) { ParScanWeakRefClosure::do_oop_work(p); }
59 inline void ParScanWeakRefClosure::do_oop_nv(narrowOop* p) { ParScanWeakRefClosure::do_oop_work(p); }
60
61 template <class T> inline void ParScanClosure::par_do_barrier(T* p) {
62 assert(generation()->is_in_reserved(p), "expected ref in generation");
63 assert(!oopDesc::is_null(*p), "expected non-null object");
64 oop obj = oopDesc::load_decode_heap_oop_not_null(p);
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 template <class T>
72 inline void ParScanClosure::do_oop_work(T* p,
73 bool gc_barrier,
74 bool root_scan) {
75 assert((!CMSHeap::heap()->is_in_reserved(p) ||
76 generation()->is_in_reserved(p))
77 && (CMSHeap::heap()->is_young_gen(generation()) || gc_barrier),
78 "The gen must be right, and we must be doing the barrier "
79 "in older generations.");
80 T heap_oop = oopDesc::load_heap_oop(p);
81 if (!oopDesc::is_null(heap_oop)) {
82 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);
83 if ((HeapWord*)obj < _boundary) {
84 #ifndef PRODUCT
85 if (_g->to()->is_in_reserved(obj)) {
86 Log(gc) log;
87 log.error("Scanning field (" PTR_FORMAT ") twice?", p2i(p));
88 CMSHeap* heap = CMSHeap::heap();
89 Space* sp = heap->space_containing(p);
90 oop obj = oop(sp->block_start(p));
91 assert((HeapWord*)obj < (HeapWord*)p, "Error");
92 log.error("Object: " PTR_FORMAT, p2i((void *)obj));
93 log.error("-------");
94 LogStream ls(log.error());
95 obj->print_on(&ls);
96 log.error("-----");
97 log.error("Heap:");
98 log.error("-----");
99 heap->print_on(&ls);
100 ShouldNotReachHere();
101 }
102 #endif
103 // OK, we need to ensure that it is copied.
104 // We read the klass and mark in this order, so that we can reliably
105 // get the size of the object: if the mark we read is not a
106 // forwarding pointer, then the klass is valid: the klass is only
107 // overwritten with an overflow next pointer after the object is
108 // forwarded.
109 Klass* objK = obj->klass();
110 markOop m = obj->mark();
111 oop new_obj;
112 if (m->is_marked()) { // Contains forwarding pointer.
113 new_obj = ParNewGeneration::real_forwardee(obj);
114 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
115 log_develop_trace(gc, scavenge)("{%s %s ( " PTR_FORMAT " ) " PTR_FORMAT " -> " PTR_FORMAT " (%d)}",
116 "forwarded ",
117 new_obj->klass()->internal_name(), p2i(p), p2i((void *)obj), p2i((void *)new_obj), new_obj->size());
118 } else {
119 size_t obj_sz = obj->size_given_klass(objK);
120 new_obj = _g->copy_to_survivor_space(_par_scan_state, obj, obj_sz, m);
121 oopDesc::encode_store_heap_oop_not_null(p, new_obj);
122 if (root_scan) {
123 // This may have pushed an object. If we have a root
124 // category with a lot of roots, can't let the queue get too
125 // full:
126 (void)_par_scan_state->trim_queues(10 * ParallelGCThreads);
127 }
128 }
129 if (is_scanning_a_cld()) {
130 do_cld_barrier();
131 } else if (gc_barrier) {
132 // Now call parent closure
133 par_do_barrier(p);
134 }
135 }
136 }
137 }
138
139 inline void ParScanWithBarrierClosure::do_oop_nv(oop* p) { ParScanClosure::do_oop_work(p, true, false); }
140 inline void ParScanWithBarrierClosure::do_oop_nv(narrowOop* p) { ParScanClosure::do_oop_work(p, true, false); }
141
142 inline void ParScanWithoutBarrierClosure::do_oop_nv(oop* p) { ParScanClosure::do_oop_work(p, false, false); }
143 inline void ParScanWithoutBarrierClosure::do_oop_nv(narrowOop* p) { ParScanClosure::do_oop_work(p, false, false); }
144
145 #endif // SHARE_VM_GC_CMS_PAROOPCLOSURES_INLINE_HPP