summaryrefslogtreecommitdiff
path: root/runtime/class_table.cc
blob: 03921a132abca21e4aa27751739fd748c738d1f2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
/*
 * Copyright (C) 2015 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "class_table-inl.h"

#include "base/stl_util.h"
#include "mirror/class-inl.h"
#include "oat_file.h"

namespace art {

ClassTable::ClassTable() : lock_("Class loader classes", kClassLoaderClassesLock) {
  Runtime* const runtime = Runtime::Current();
  classes_.push_back(ClassSet(runtime->GetHashTableMinLoadFactor(),
                              runtime->GetHashTableMaxLoadFactor()));
}

void ClassTable::FreezeSnapshot() {
  WriterMutexLock mu(Thread::Current(), lock_);
  classes_.push_back(ClassSet());
}

ObjPtr<mirror::Class> ClassTable::UpdateClass(const char* descriptor,
                                              ObjPtr<mirror::Class> klass,
                                              size_t hash) {
  WriterMutexLock mu(Thread::Current(), lock_);
  // Should only be updating latest table.
  DescriptorHashPair pair(descriptor, hash);
  auto existing_it = classes_.back().FindWithHash(pair, hash);
  if (existing_it == classes_.back().end()) {
    for (const ClassSet& class_set : classes_) {
      if (class_set.FindWithHash(pair, hash) != class_set.end()) {
        LOG(FATAL) << "Updating class found in frozen table " << descriptor;
      }
    }
    LOG(FATAL) << "Updating class not found " << descriptor;
  }
  const ObjPtr<mirror::Class> existing = existing_it->Read();
  CHECK_NE(existing, klass) << descriptor;
  CHECK(!existing->IsResolved()) << descriptor;
  CHECK_EQ(klass->GetStatus(), ClassStatus::kResolving) << descriptor;
  CHECK(!klass->IsTemp()) << descriptor;
  VerifyObject(klass);
  // Update the element in the hash set with the new class. This is safe to do since the descriptor
  // doesn't change.
  *existing_it = TableSlot(klass, hash);
  return existing;
}

size_t ClassTable::CountDefiningLoaderClasses(ObjPtr<mirror::ClassLoader> defining_loader,
                                              const ClassSet& set) const {
  size_t count = 0;
  for (const TableSlot& root : set) {
    if (root.Read()->GetClassLoader() == defining_loader) {
      ++count;
    }
  }
  return count;
}

size_t ClassTable::NumZygoteClasses(ObjPtr<mirror::ClassLoader> defining_loader) const {
  ReaderMutexLock mu(Thread::Current(), lock_);
  size_t sum = 0;
  for (size_t i = 0; i < classes_.size() - 1; ++i) {
    sum += CountDefiningLoaderClasses(defining_loader, classes_[i]);
  }
  return sum;
}

size_t ClassTable::NumNonZygoteClasses(ObjPtr<mirror::ClassLoader> defining_loader) const {
  ReaderMutexLock mu(Thread::Current(), lock_);
  return CountDefiningLoaderClasses(defining_loader, classes_.back());
}

size_t ClassTable::NumReferencedZygoteClasses() const {
  ReaderMutexLock mu(Thread::Current(), lock_);
  size_t sum = 0;
  for (size_t i = 0; i < classes_.size() - 1; ++i) {
    sum += classes_[i].size();
  }
  return sum;
}

size_t ClassTable::NumReferencedNonZygoteClasses() const {
  ReaderMutexLock mu(Thread::Current(), lock_);
  return classes_.back().size();
}

ObjPtr<mirror::Class> ClassTable::Lookup(const char* descriptor, size_t hash) {
  DescriptorHashPair pair(descriptor, hash);
  ReaderMutexLock mu(Thread::Current(), lock_);
  for (ClassSet& class_set : classes_) {
    auto it = class_set.FindWithHash(pair, hash);
    if (it != class_set.end()) {
      return it->Read();
    }
  }
  return nullptr;
}

void ClassTable::Insert(ObjPtr<mirror::Class> klass) {
  InsertWithHash(klass, TableSlot::HashDescriptor(klass));
}

void ClassTable::InsertWithHash(ObjPtr<mirror::Class> klass, size_t hash) {
  WriterMutexLock mu(Thread::Current(), lock_);
  classes_.back().InsertWithHash(TableSlot(klass, hash), hash);
}

bool ClassTable::Remove(const char* descriptor) {
  DescriptorHashPair pair(descriptor, ComputeModifiedUtf8Hash(descriptor));
  WriterMutexLock mu(Thread::Current(), lock_);
  for (ClassSet& class_set : classes_) {
    auto it = class_set.find(pair);
    if (it != class_set.end()) {
      class_set.erase(it);
      return true;
    }
  }
  return false;
}

bool ClassTable::InsertStrongRoot(ObjPtr<mirror::Object> obj) {
  WriterMutexLock mu(Thread::Current(), lock_);
  DCHECK(obj != nullptr);
  for (GcRoot<mirror::Object>& root : strong_roots_) {
    if (root.Read() == obj) {
      return false;
    }
  }
  strong_roots_.push_back(GcRoot<mirror::Object>(obj));
  // If `obj` is a dex cache associated with a new oat file with GC roots, add it to oat_files_.
  if (obj->IsDexCache()) {
    const DexFile* dex_file = ObjPtr<mirror::DexCache>::DownCast(obj)->GetDexFile();
    if (dex_file != nullptr && dex_file->GetOatDexFile() != nullptr) {
      const OatFile* oat_file = dex_file->GetOatDexFile()->GetOatFile();
      if (oat_file != nullptr && !oat_file->GetBssGcRoots().empty()) {
        InsertOatFileLocked(oat_file);  // Ignore return value.
      }
    }
  }
  return true;
}

bool ClassTable::InsertOatFile(const OatFile* oat_file) {
  WriterMutexLock mu(Thread::Current(), lock_);
  return InsertOatFileLocked(oat_file);
}

bool ClassTable::InsertOatFileLocked(const OatFile* oat_file) {
  if (ContainsElement(oat_files_, oat_file)) {
    return false;
  }
  oat_files_.push_back(oat_file);
  return true;
}

size_t ClassTable::ReadFromMemory(uint8_t* ptr) {
  size_t read_count = 0;
  AddClassSet(ClassSet(ptr, /*make copy*/false, &read_count));
  return read_count;
}

void ClassTable::AddClassSet(ClassSet&& set) {
  WriterMutexLock mu(Thread::Current(), lock_);
  classes_.insert(classes_.begin(), std::move(set));
}

void ClassTable::ClearStrongRoots() {
  WriterMutexLock mu(Thread::Current(), lock_);
  oat_files_.clear();
  strong_roots_.clear();
}

ClassTable::TableSlot::TableSlot(ObjPtr<mirror::Class> klass)
    : TableSlot(klass, HashDescriptor(klass)) {}

uint32_t ClassTable::TableSlot::HashDescriptor(ObjPtr<mirror::Class> klass) {
  std::string temp;
  return ComputeModifiedUtf8Hash(klass->GetDescriptor(&temp));
}

}  // namespace art