1 /*
2 * Copyright (c) 2017, 2024, 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_GC_G1_G1FULLGCMARKER_INLINE_HPP
26 #define SHARE_GC_G1_G1FULLGCMARKER_INLINE_HPP
27
28 #include "gc/g1/g1FullGCMarker.hpp"
29
30 #include "classfile/classLoaderData.hpp"
31 #include "classfile/javaClasses.inline.hpp"
32 #include "gc/g1/g1Allocator.inline.hpp"
33 #include "gc/g1/g1ConcurrentMarkBitMap.inline.hpp"
34 #include "gc/g1/g1FullCollector.inline.hpp"
35 #include "gc/g1/g1FullGCOopClosures.inline.hpp"
36 #include "gc/g1/g1OopClosures.inline.hpp"
37 #include "gc/g1/g1RegionMarkStatsCache.hpp"
38 #include "gc/g1/g1StringDedup.hpp"
39 #include "gc/shared/continuationGCSupport.inline.hpp"
40 #include "gc/shared/preservedMarks.inline.hpp"
41 #include "gc/shared/stringdedup/stringDedup.hpp"
42 #include "oops/access.inline.hpp"
43 #include "oops/compressedOops.inline.hpp"
44 #include "oops/oop.inline.hpp"
45 #include "utilities/debug.hpp"
46
47 inline bool G1FullGCMarker::mark_object(oop obj) {
48 // Try to mark.
49 if (!_bitmap->par_mark(obj)) {
50 // Lost mark race.
51 return false;
52 }
53
54 // Check if deduplicatable string.
55 if (StringDedup::is_enabled() &&
56 java_lang_String::is_instance(obj) &&
57 G1StringDedup::is_candidate_from_mark(obj)) {
58 _string_dedup_requests.add(obj);
59 }
60
61 ContinuationGCSupport::transform_stack_chunk(obj);
62
63 // Collect live words.
64 _mark_stats_cache.add_live_words(obj);
65
66 return true;
67 }
68
69 template <class T> inline void G1FullGCMarker::mark_and_push(T* p) {
70 T heap_oop = RawAccess<>::oop_load(p);
71 if (!CompressedOops::is_null(heap_oop)) {
72 oop obj = CompressedOops::decode_not_null(heap_oop);
73 if (mark_object(obj)) {
74 _oop_stack.push(obj);
75 }
76 assert(_bitmap->is_marked(obj), "Must be marked");
77 }
78 }
79
80 inline bool G1FullGCMarker::is_empty() {
81 return _oop_stack.is_empty() && _objarray_stack.is_empty();
82 }
83
84 inline void G1FullGCMarker::push_objarray(oop obj, size_t index) {
85 ObjArrayTask task(obj, index);
86 assert(task.is_valid(), "bad ObjArrayTask");
87 _objarray_stack.push(task);
88 }
89
90 inline void G1FullGCMarker::follow_array(objArrayOop array) {
91 mark_closure()->do_klass(array->klass());
92 // Don't push empty arrays to avoid unnecessary work.
93 if (array->length() > 0) {
94 push_objarray(array, 0);
95 }
96 }
97
98 void G1FullGCMarker::follow_array_chunk(objArrayOop array, int index) {
99 const int len = array->length();
100 const int beg_index = index;
101 assert(beg_index < len || len == 0, "index too large");
102
103 const int stride = MIN2(len - beg_index, (int) ObjArrayMarkingStride);
104 const int end_index = beg_index + stride;
105
106 // Push the continuation first to allow more efficient work stealing.
107 if (end_index < len) {
108 push_objarray(array, end_index);
109 }
110
111 array->oop_iterate_range(mark_closure(), beg_index, end_index);
112 }
113
114 inline void G1FullGCMarker::follow_object(oop obj) {
115 assert(_bitmap->is_marked(obj), "should be marked");
116 if (obj->is_objArray()) {
117 // Handle object arrays explicitly to allow them to
118 // be split into chunks if needed.
119 follow_array((objArrayOop)obj);
120 } else {
121 obj->oop_iterate(mark_closure());
122 }
123 }
124
125 inline void G1FullGCMarker::publish_and_drain_oop_tasks() {
126 oop obj;
127 while (_oop_stack.pop_overflow(obj)) {
128 if (!_oop_stack.try_push_to_taskqueue(obj)) {
129 assert(_bitmap->is_marked(obj), "must be marked");
130 follow_object(obj);
131 }
132 }
133 while (_oop_stack.pop_local(obj)) {
134 assert(_bitmap->is_marked(obj), "must be marked");
135 follow_object(obj);
136 }
137 }
138
139 inline bool G1FullGCMarker::publish_or_pop_objarray_tasks(ObjArrayTask& task) {
140 // It is desirable to move as much as possible work from the overflow queue to
141 // the shared queue as quickly as possible.
142 while (_objarray_stack.pop_overflow(task)) {
143 if (!_objarray_stack.try_push_to_taskqueue(task)) {
144 return true;
145 }
146 }
147 return false;
148 }
149
150 void G1FullGCMarker::follow_marking_stacks() {
151 do {
152 // First, drain regular oop stack.
153 publish_and_drain_oop_tasks();
154
155 // Then process ObjArrays one at a time to avoid marking stack bloat.
156 ObjArrayTask task;
157 if (publish_or_pop_objarray_tasks(task) ||
158 _objarray_stack.pop_local(task)) {
159 follow_array_chunk(objArrayOop(task.obj()), task.index());
160 }
161 } while (!is_empty());
162 }
163
164 #endif // SHARE_GC_G1_G1FULLGCMARKER_INLINE_HPP