1 /*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #ifndef ART_RUNTIME_CLASS_TABLE_INL_H_
18 #define ART_RUNTIME_CLASS_TABLE_INL_H_
19
20 #include "class_table.h"
21
22 #include "base/mutex-inl.h"
23 #include "gc_root-inl.h"
24 #include "mirror/class.h"
25 #include "oat_file.h"
26
27 namespace art {
28
29 template<class Visitor>
VisitRoots(Visitor & visitor)30 void ClassTable::VisitRoots(Visitor& visitor) {
31 ReaderMutexLock mu(Thread::Current(), lock_);
32 for (ClassSet& class_set : classes_) {
33 for (TableSlot& table_slot : class_set) {
34 table_slot.VisitRoot(visitor);
35 }
36 }
37 for (GcRoot<mirror::Object>& root : strong_roots_) {
38 visitor.VisitRoot(root.AddressWithoutBarrier());
39 }
40 for (const OatFile* oat_file : oat_files_) {
41 for (GcRoot<mirror::Object>& root : oat_file->GetBssGcRoots()) {
42 visitor.VisitRootIfNonNull(root.AddressWithoutBarrier());
43 }
44 }
45 }
46
47 template<class Visitor>
VisitRoots(const Visitor & visitor)48 void ClassTable::VisitRoots(const Visitor& visitor) {
49 ReaderMutexLock mu(Thread::Current(), lock_);
50 for (ClassSet& class_set : classes_) {
51 for (TableSlot& table_slot : class_set) {
52 table_slot.VisitRoot(visitor);
53 }
54 }
55 for (GcRoot<mirror::Object>& root : strong_roots_) {
56 visitor.VisitRoot(root.AddressWithoutBarrier());
57 }
58 for (const OatFile* oat_file : oat_files_) {
59 for (GcRoot<mirror::Object>& root : oat_file->GetBssGcRoots()) {
60 visitor.VisitRootIfNonNull(root.AddressWithoutBarrier());
61 }
62 }
63 }
64
65 template <typename Visitor, ReadBarrierOption kReadBarrierOption>
Visit(Visitor & visitor)66 bool ClassTable::Visit(Visitor& visitor) {
67 ReaderMutexLock mu(Thread::Current(), lock_);
68 for (ClassSet& class_set : classes_) {
69 for (TableSlot& table_slot : class_set) {
70 if (!visitor(table_slot.Read<kReadBarrierOption>())) {
71 return false;
72 }
73 }
74 }
75 return true;
76 }
77
78 template <typename Visitor, ReadBarrierOption kReadBarrierOption>
Visit(const Visitor & visitor)79 bool ClassTable::Visit(const Visitor& visitor) {
80 ReaderMutexLock mu(Thread::Current(), lock_);
81 for (ClassSet& class_set : classes_) {
82 for (TableSlot& table_slot : class_set) {
83 if (!visitor(table_slot.Read<kReadBarrierOption>())) {
84 return false;
85 }
86 }
87 }
88 return true;
89 }
90
91 template<ReadBarrierOption kReadBarrierOption>
Read()92 inline mirror::Class* ClassTable::TableSlot::Read() const {
93 const uint32_t before = data_.load(std::memory_order_relaxed);
94 const ObjPtr<mirror::Class> before_ptr(ExtractPtr(before));
95 const ObjPtr<mirror::Class> after_ptr(
96 GcRoot<mirror::Class>(before_ptr).Read<kReadBarrierOption>());
97 if (kReadBarrierOption != kWithoutReadBarrier && before_ptr != after_ptr) {
98 // If another thread raced and updated the reference, do not store the read barrier updated
99 // one.
100 data_.CompareAndSetStrongRelease(before, Encode(after_ptr, MaskHash(before)));
101 }
102 return after_ptr.Ptr();
103 }
104
105 template<typename Visitor>
VisitRoot(const Visitor & visitor)106 inline void ClassTable::TableSlot::VisitRoot(const Visitor& visitor) const {
107 const uint32_t before = data_.load(std::memory_order_relaxed);
108 ObjPtr<mirror::Class> before_ptr(ExtractPtr(before));
109 GcRoot<mirror::Class> root(before_ptr);
110 visitor.VisitRoot(root.AddressWithoutBarrier());
111 ObjPtr<mirror::Class> after_ptr(root.Read<kWithoutReadBarrier>());
112 if (before_ptr != after_ptr) {
113 // If another thread raced and updated the reference, do not store the read barrier updated
114 // one.
115 data_.CompareAndSetStrongRelease(before, Encode(after_ptr, MaskHash(before)));
116 }
117 }
118
ExtractPtr(uint32_t data)119 inline ObjPtr<mirror::Class> ClassTable::TableSlot::ExtractPtr(uint32_t data) {
120 return reinterpret_cast<mirror::Class*>(data & ~kHashMask);
121 }
122
Encode(ObjPtr<mirror::Class> klass,uint32_t hash_bits)123 inline uint32_t ClassTable::TableSlot::Encode(ObjPtr<mirror::Class> klass, uint32_t hash_bits) {
124 DCHECK_LE(hash_bits, kHashMask);
125 return reinterpret_cast<uintptr_t>(klass.Ptr()) | hash_bits;
126 }
127
TableSlot(ObjPtr<mirror::Class> klass,uint32_t descriptor_hash)128 inline ClassTable::TableSlot::TableSlot(ObjPtr<mirror::Class> klass, uint32_t descriptor_hash)
129 : data_(Encode(klass, MaskHash(descriptor_hash))) {
130 if (kIsDebugBuild) {
131 std::string temp;
132 const uint32_t hash = ComputeModifiedUtf8Hash(klass->GetDescriptor(&temp));
133 CHECK_EQ(descriptor_hash, hash);
134 }
135 }
136
137 template <typename Filter>
RemoveStrongRoots(const Filter & filter)138 inline void ClassTable::RemoveStrongRoots(const Filter& filter) {
139 WriterMutexLock mu(Thread::Current(), lock_);
140 strong_roots_.erase(std::remove_if(strong_roots_.begin(), strong_roots_.end(), filter),
141 strong_roots_.end());
142 }
143
144 } // namespace art
145
146 #endif // ART_RUNTIME_CLASS_TABLE_INL_H_
147