1 /*
2 * Copyright (c) 2015, 2020, 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 #ifndef SHARE_GC_Z_ZLIVEMAP_INLINE_HPP
25 #define SHARE_GC_Z_ZLIVEMAP_INLINE_HPP
26
27 #include "gc/z/zLiveMap.hpp"
28
29 #include "gc/z/zBitMap.inline.hpp"
30 #include "gc/z/zMark.hpp"
31 #include "gc/z/zOop.inline.hpp"
32 #include "gc/z/zUtils.inline.hpp"
33 #include "runtime/atomic.hpp"
34 #include "utilities/bitMap.inline.hpp"
35 #include "utilities/debug.hpp"
36
37 inline void ZLiveMap::reset() {
38 _seqnum = 0;
39 }
40
41 inline bool ZLiveMap::is_marked() const {
42 return Atomic::load_acquire(&_seqnum) == ZGlobalSeqNum;
43 }
44
45 inline uint32_t ZLiveMap::live_objects() const {
46 assert(ZGlobalPhase != ZPhaseMark, "Invalid phase");
47 return _live_objects;
48 }
49
50 inline size_t ZLiveMap::live_bytes() const {
51 assert(ZGlobalPhase != ZPhaseMark, "Invalid phase");
52 return _live_bytes;
53 }
54
55 inline const BitMapView ZLiveMap::segment_live_bits() const {
56 return BitMapView(const_cast<BitMap::bm_word_t*>(&_segment_live_bits), nsegments);
57 }
58
59 inline const BitMapView ZLiveMap::segment_claim_bits() const {
60 return BitMapView(const_cast<BitMap::bm_word_t*>(&_segment_claim_bits), nsegments);
61 }
62
63 inline BitMapView ZLiveMap::segment_live_bits() {
64 return BitMapView(&_segment_live_bits, nsegments);
65 }
66
67 inline BitMapView ZLiveMap::segment_claim_bits() {
68 return BitMapView(&_segment_claim_bits, nsegments);
69 }
70
71 inline bool ZLiveMap::is_segment_live(BitMap::idx_t segment) const {
72 return segment_live_bits().par_at(segment);
73 }
74
75 inline bool ZLiveMap::set_segment_live(BitMap::idx_t segment) {
76 return segment_live_bits().par_set_bit(segment, memory_order_release);
77 }
78
79 inline bool ZLiveMap::claim_segment(BitMap::idx_t segment) {
80 return segment_claim_bits().par_set_bit(segment, memory_order_acq_rel);
81 }
82
83 inline BitMap::idx_t ZLiveMap::first_live_segment() const {
84 return segment_live_bits().get_next_one_offset(0, nsegments);
85 }
86
87 inline BitMap::idx_t ZLiveMap::next_live_segment(BitMap::idx_t segment) const {
88 return segment_live_bits().get_next_one_offset(segment + 1, nsegments);
89 }
90
91 inline BitMap::idx_t ZLiveMap::segment_size() const {
92 return _bitmap.size() / nsegments;
93 }
94
95 inline BitMap::idx_t ZLiveMap::index_to_segment(BitMap::idx_t index) const {
96 return index >> _segment_shift;
97 }
98
99 inline bool ZLiveMap::get(size_t index) const {
100 BitMap::idx_t segment = index_to_segment(index);
101 return is_marked() && // Page is marked
102 is_segment_live(segment) && // Segment is marked
103 _bitmap.at(index); // Object is marked
104 }
105
106 inline bool ZLiveMap::set(size_t index, bool finalizable, bool& inc_live) {
107 if (!is_marked()) {
108 // First object to be marked during this
109 // cycle, reset marking information.
110 reset(index);
111 }
112
113 const BitMap::idx_t segment = index_to_segment(index);
114 if (!is_segment_live(segment)) {
115 // First object to be marked in this segment during
116 // this cycle, reset segment bitmap.
117 reset_segment(segment);
118 }
119
120 return _bitmap.par_set_bit_pair(index, finalizable, inc_live);
121 }
122
123 inline void ZLiveMap::inc_live(uint32_t objects, size_t bytes) {
124 Atomic::add(&_live_objects, objects);
125 Atomic::add(&_live_bytes, bytes);
126 }
127
128 inline BitMap::idx_t ZLiveMap::segment_start(BitMap::idx_t segment) const {
129 return segment_size() * segment;
130 }
131
132 inline BitMap::idx_t ZLiveMap::segment_end(BitMap::idx_t segment) const {
133 return segment_start(segment) + segment_size();
134 }
135
136 inline void ZLiveMap::iterate_segment(ObjectClosure* cl, BitMap::idx_t segment, uintptr_t page_start, size_t page_object_alignment_shift) {
137 assert(is_segment_live(segment), "Must be");
138
139 const BitMap::idx_t start_index = segment_start(segment);
140 const BitMap::idx_t end_index = segment_end(segment);
141 BitMap::idx_t index = _bitmap.get_next_one_offset(start_index, end_index);
142
143 while (index < end_index) {
144 // Calculate object address
145 const uintptr_t addr = page_start + ((index / 2) << page_object_alignment_shift);
146
147 // Get the size of the object before calling the closure, which
148 // might overwrite the object in case we are relocating in-place.
149 const size_t size = ZUtils::object_size(addr);
150
151 // Apply closure
152 cl->do_object(ZOop::from_address(addr));
153
154 // Find next bit after this object
155 const uintptr_t next_addr = align_up(addr + size, 1 << page_object_alignment_shift);
156 const BitMap::idx_t next_index = ((next_addr - page_start) >> page_object_alignment_shift) * 2;
157 if (next_index >= end_index) {
158 // End of live map
159 break;
160 }
161
162 index = _bitmap.get_next_one_offset(next_index, end_index);
163 }
164 }
165
166 inline void ZLiveMap::iterate(ObjectClosure* cl, uintptr_t page_start, size_t page_object_alignment_shift) {
167 if (is_marked()) {
168 for (BitMap::idx_t segment = first_live_segment(); segment < nsegments; segment = next_live_segment(segment)) {
169 // For each live segment
170 iterate_segment(cl, segment, page_start, page_object_alignment_shift);
171 }
172 }
173 }
174
175 #endif // SHARE_GC_Z_ZLIVEMAP_INLINE_HPP