1 /*
2 * Copyright (c) 2001, 2010, 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_IMPLEMENTATION_G1_G1SATBCARDTABLEMODREFBS_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1SATBCARDTABLEMODREFBS_HPP
27
28 #include "memory/cardTableModRefBS.hpp"
29 #include "memory/memRegion.hpp"
30 #include "oops/oop.inline.hpp"
31
32 #ifndef SERIALGC
33
34 class DirtyCardQueueSet;
35
36 // This barrier is specialized to use a logging barrier to support
37 // snapshot-at-the-beginning marking.
38
39 class G1SATBCardTableModRefBS: public CardTableModRefBSForCTRS {
40 private:
41 // Add "pre_val" to a set of objects that may have been disconnected from the
42 // pre-marking object graph.
43 static void enqueue(oop pre_val);
44
45 public:
46 G1SATBCardTableModRefBS(MemRegion whole_heap,
47 int max_covered_regions);
48
49 bool is_a(BarrierSet::Name bsn) {
50 return bsn == BarrierSet::G1SATBCT || CardTableModRefBS::is_a(bsn);
51 }
52
53 virtual bool has_write_ref_pre_barrier() { return true; }
54
55 // This notes that we don't need to access any BarrierSet data
56 // structures, so this can be called from a static context.
57 template <class T> static void write_ref_field_pre_static(T* field, oop newVal) {
58 T heap_oop = oopDesc::load_heap_oop(field);
59 if (!oopDesc::is_null(heap_oop)) {
60 enqueue(oopDesc::decode_heap_oop(heap_oop));
61 }
62 }
63
64 // When we know the current java thread:
65 template <class T> static void write_ref_field_pre_static(T* field, oop newVal,
66 JavaThread* jt);
67
68 // We export this to make it available in cases where the static
69 // type of the barrier set is known. Note that it is non-virtual.
70 template <class T> inline void inline_write_ref_field_pre(T* field, oop newVal) {
71 write_ref_field_pre_static(field, newVal);
72 }
73
74 // These are the more general virtual versions.
75 virtual void write_ref_field_pre_work(oop* field, oop new_val) {
76 inline_write_ref_field_pre(field, new_val);
77 }
78 virtual void write_ref_field_pre_work(narrowOop* field, oop new_val) {
79 inline_write_ref_field_pre(field, new_val);
80 }
81 virtual void write_ref_field_pre_work(void* field, oop new_val) {
82 guarantee(false, "Not needed");
83 }
84
85 template <class T> void write_ref_array_pre_work(T* dst, int count);
86 virtual void write_ref_array_pre(oop* dst, int count) {
87 write_ref_array_pre_work(dst, count);
88 }
89 virtual void write_ref_array_pre(narrowOop* dst, int count) {
90 write_ref_array_pre_work(dst, count);
91 }
92 };
93
94 // Adds card-table logging to the post-barrier.
95 // Usual invariant: all dirty cards are logged in the DirtyCardQueueSet.
96 class G1SATBCardTableLoggingModRefBS: public G1SATBCardTableModRefBS {
97 private:
98 DirtyCardQueueSet& _dcqs;
99 public:
100 G1SATBCardTableLoggingModRefBS(MemRegion whole_heap,
101 int max_covered_regions);
102
103 bool is_a(BarrierSet::Name bsn) {
104 return bsn == BarrierSet::G1SATBCTLogging ||
105 G1SATBCardTableModRefBS::is_a(bsn);
106 }
107
108 void write_ref_field_work(void* field, oop new_val);
109
110 // Can be called from static contexts.
111 static void write_ref_field_static(void* field, oop new_val);
112
113 // NB: if you do a whole-heap invalidation, the "usual invariant" defined
114 // above no longer applies.
115 void invalidate(MemRegion mr, bool whole_heap = false);
116
117 void write_region_work(MemRegion mr) { invalidate(mr); }
118 void write_ref_array_work(MemRegion mr) { invalidate(mr); }
119
120
121 };
122
123
124 #endif // SERIALGC
125
126 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1SATBCARDTABLEMODREFBS_HPP