1 /*
2 * Copyright (c) 2007, 2018, 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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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 #include "oops/access.inline.hpp"
36 #include "oops/compressedOops.inline.hpp"
37 #include "oops/oop.inline.hpp"
38
39 template <class T> inline void ParScanWeakRefClosure::do_oop_work(T* p) {
40 oop obj = RawAccess<IS_NOT_NULL>::oop_load(p);
41 // weak references are sometimes scanned twice; must check
42 // that to-space doesn't already contain this object
43 if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) {
44 // we need to ensure that it is copied (see comment in
45 // ParScanClosure::do_oop_work).
46 Klass* objK = obj->klass();
47 markOop m = obj->mark_raw();
48 oop new_obj;
49 if (m->is_marked()) { // Contains forwarding pointer.
50 new_obj = ParNewGeneration::real_forwardee(obj);
51 } else {
52 size_t obj_sz = obj->size_given_klass(objK);
53 new_obj = ((ParNewGeneration*)_g)->copy_to_survivor_space(_par_scan_state,
54 obj, obj_sz, m);
55 }
56 RawAccess<IS_NOT_NULL>::oop_store(p, new_obj);
57 }
58 }
59
60 inline void ParScanWeakRefClosure::do_oop(oop* p) { ParScanWeakRefClosure::do_oop_work(p); }
61 inline void ParScanWeakRefClosure::do_oop(narrowOop* p) { ParScanWeakRefClosure::do_oop_work(p); }
62
63 template <class T> inline void ParScanClosure::par_do_barrier(T* p) {
64 assert(generation()->is_in_reserved(p), "expected ref in generation");
65 oop obj = RawAccess<IS_NOT_NULL>::oop_load(p);
66 // If p points to a younger generation, mark the card.
67 if ((HeapWord*)obj < gen_boundary()) {
68 rs()->write_ref_field_gc_par(p, obj);
69 }
70 }
71
72 template <class T>
73 inline void ParScanClosure::do_oop_work(T* p,
74 bool gc_barrier,
75 bool root_scan) {
76 assert((!CMSHeap::heap()->is_in_reserved(p) ||
77 generation()->is_in_reserved(p))
78 && (CMSHeap::heap()->is_young_gen(generation()) || gc_barrier),
79 "The gen must be right, and we must be doing the barrier "
80 "in older generations.");
81 T heap_oop = RawAccess<>::oop_load(p);
82 if (!CompressedOops::is_null(heap_oop)) {
83 oop obj = CompressedOops::decode_not_null(heap_oop);
84 if ((HeapWord*)obj < _boundary) {
85 #ifndef PRODUCT
86 if (_g->to()->is_in_reserved(obj)) {
87 Log(gc) log;
88 log.error("Scanning field (" PTR_FORMAT ") twice?", p2i(p));
89 CMSHeap* heap = CMSHeap::heap();
90 Space* sp = heap->space_containing(p);
91 oop obj = oop(sp->block_start(p));
92 assert((HeapWord*)obj < (HeapWord*)p, "Error");
93 log.error("Object: " PTR_FORMAT, p2i((void *)obj));
94 log.error("-------");
95 LogStream ls(log.error());
96 oopDesc::print_on(&ls, obj);
97 log.error("-----");
98 log.error("Heap:");
99 log.error("-----");
100 heap->print_on(&ls);
101 ShouldNotReachHere();
102 }
103 #endif
104 // OK, we need to ensure that it is copied.
105 // We read the klass and mark in this order, so that we can reliably
106 // get the size of the object: if the mark we read is not a
107 // forwarding pointer, then the klass is valid: the klass is only
108 // overwritten with an overflow next pointer after the object is
109 // forwarded.
110 Klass* objK = obj->klass();
111 markOop m = obj->mark_raw();
112 oop new_obj;
113 if (m->is_marked()) { // Contains forwarding pointer.
114 new_obj = ParNewGeneration::real_forwardee(obj);
115 RawAccess<IS_NOT_NULL>::oop_store(p, new_obj);
116 log_develop_trace(gc, scavenge)("{%s %s ( " PTR_FORMAT " ) " PTR_FORMAT " -> " PTR_FORMAT " (%d)}",
117 "forwarded ",
118 new_obj->klass()->internal_name(), p2i(p), p2i((void *)obj), p2i((void *)new_obj), new_obj->size());
119 } else {
120 size_t obj_sz = obj->size_given_klass(objK);
121 new_obj = _g->copy_to_survivor_space(_par_scan_state, obj, obj_sz, m);
122 RawAccess<IS_NOT_NULL>::oop_store(p, new_obj);
123 if (root_scan) {
124 // This may have pushed an object. If we have a root
125 // category with a lot of roots, can't let the queue get too
126 // full:
127 (void)_par_scan_state->trim_queues(10 * ParallelGCThreads);
128 }
129 }
130 if (is_scanning_a_cld()) {
131 do_cld_barrier();
132 } else if (gc_barrier) {
133 // Now call parent closure
134 par_do_barrier(p);
135 }
136 }
137 }
138 }
139
140 inline void ParScanWithBarrierClosure::do_oop(oop* p) { ParScanClosure::do_oop_work(p, true, false); }
141 inline void ParScanWithBarrierClosure::do_oop(narrowOop* p) { ParScanClosure::do_oop_work(p, true, false); }
142
143 inline void ParScanWithoutBarrierClosure::do_oop(oop* p) { ParScanClosure::do_oop_work(p, false, false); }
144 inline void ParScanWithoutBarrierClosure::do_oop(narrowOop* p) { ParScanClosure::do_oop_work(p, false, false); }
145
146 #endif // SHARE_VM_GC_CMS_PAROOPCLOSURES_INLINE_HPP