1 /*
2 * Copyright (c) 2016, 2019, 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_G1BARRIERSET_INLINE_HPP
26 #define SHARE_GC_G1_G1BARRIERSET_INLINE_HPP
27
28 #include "gc/g1/g1BarrierSet.hpp"
29 #include "gc/g1/g1CardTable.hpp"
30 #include "gc/shared/accessBarrierSupport.inline.hpp"
31 #include "oops/access.inline.hpp"
32 #include "oops/compressedOops.inline.hpp"
33 #include "oops/oop.hpp"
34 #ifdef ASSERT
35 #include "runtime/thread.inline.hpp"
36 #endif
37
38 template <DecoratorSet decorators, typename T>
39 inline void G1BarrierSet::write_ref_field_pre(T* field) {
40 if (HasDecorator<decorators, IS_DEST_UNINITIALIZED>::value ||
41 HasDecorator<decorators, AS_NO_KEEPALIVE>::value) {
42 return;
43 }
44
45 T heap_oop = RawAccess<MO_VOLATILE>::oop_load(field);
46 if (!CompressedOops::is_null(heap_oop)) {
47 enqueue(CompressedOops::decode_not_null(heap_oop));
48 }
49 }
50
51 template <DecoratorSet decorators, typename T>
52 inline void G1BarrierSet::write_ref_field_post(T* field, oop new_val) {
53 /*
54 #ifdef ASSERT
55 if (Thread::current()->is_Java_thread()) {
56 JavaThreadState s = ((JavaThread*)Thread::current())->thread_state();
57 if (s != _thread_in_vm) {
58 tty->print_cr("T(%s).state = %d", Thread::current()->name(), s);
59 assert(false, "fail");
60 }
61 } else {
62 tty->print_cr("T(%s) not JavaThread", Thread::current()->name());
63 tty->print_cr("At safepoint? %d", SafepointSynchronize::is_at_safepoint());
64 assert(false, "fail");
65 }
66 #endif
67 */
68 // assert(SafepointSynchronize::is_at_safepoint() ||
69 // (Thread::current()->is_Java_thread() &&
70 // ((JavaThread*)Thread::current())->thread_state() == _thread_in_vm),
71 // "sanity");
72
73 volatile CardValue* byte = _card_table->byte_for(field);
74 if (*byte != G1CardTable::g1_young_card_val()) {
75 // Take a slow path for cards in old
76 write_ref_field_post_slow(byte);
77 }
78 }
79
80 inline void G1BarrierSet::enqueue_if_weak(DecoratorSet decorators, oop value) {
81 assert((decorators & ON_UNKNOWN_OOP_REF) == 0, "Reference strength must be known");
82 // Loading from a weak or phantom reference needs enqueueing, as
83 // the object may not have been reachable (part of the snapshot)
84 // when marking started.
85 const bool on_strong_oop_ref = (decorators & ON_STRONG_OOP_REF) != 0;
86 const bool peek = (decorators & AS_NO_KEEPALIVE) != 0;
87 const bool needs_enqueue = (!peek && !on_strong_oop_ref);
88
89 if (needs_enqueue && value != NULL) {
90 enqueue(value);
91 }
92 }
93
94 template <DecoratorSet decorators, typename BarrierSetT>
95 template <typename T>
96 inline oop G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::
97 oop_load_not_in_heap(T* addr) {
98 oop value = ModRef::oop_load_not_in_heap(addr);
99 enqueue_if_weak(decorators, value);
100 return value;
101 }
102
103 template <DecoratorSet decorators, typename BarrierSetT>
104 template <typename T>
105 inline oop G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::
106 oop_load_in_heap(T* addr) {
107 oop value = ModRef::oop_load_in_heap(addr);
108 enqueue_if_weak(decorators, value);
109 return value;
110 }
111
112 template <DecoratorSet decorators, typename BarrierSetT>
113 inline oop G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::
114 oop_load_in_heap_at(oop base, ptrdiff_t offset) {
115 oop value = ModRef::oop_load_in_heap_at(base, offset);
116 enqueue_if_weak(AccessBarrierSupport::resolve_possibly_unknown_oop_ref_strength<decorators>(base, offset), value);
117 return value;
118 }
119
120 template <DecoratorSet decorators, typename BarrierSetT>
121 template <typename T>
122 inline void G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::
123 oop_store_not_in_heap(T* addr, oop new_value) {
124 // Apply SATB barriers for all non-heap references, to allow
125 // concurrent scanning of such references.
126 G1BarrierSet *bs = barrier_set_cast<G1BarrierSet>(BarrierSet::barrier_set());
127 bs->write_ref_field_pre<decorators>(addr);
128 Raw::oop_store(addr, new_value);
129 }
130
131 #endif // SHARE_GC_G1_G1BARRIERSET_INLINE_HPP