monitor_pool.cc revision 85ae517ebb093d6c3bcc86f87b5a70c720cefd04 
1/*
2 * Copyright (C) 2014 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#include "monitor_pool.h"
18
19#include "base/logging.h"
20#include "base/mutex-inl.h"
21#include "monitor.h"
22
23namespace art {
24
25MonitorPool::MonitorPool() : allocated_ids_lock_("allocated monitor ids lock",
26                                                 LockLevel::kMonitorPoolLock) {
27}
28
29Monitor* MonitorPool::LookupMonitorFromTable(MonitorId mon_id) {
30  ReaderMutexLock mu(Thread::Current(), allocated_ids_lock_);
31  return table_.Get(mon_id);
32}
33
34MonitorId MonitorPool::AllocMonitorIdFromTable(Thread* self, Monitor* mon) {
35  WriterMutexLock mu(self, allocated_ids_lock_);
36  for (size_t i = 0; i < allocated_ids_.size(); ++i) {
37    if (!allocated_ids_[i]) {
38      allocated_ids_.set(i);
39      MonitorId mon_id = i + 1;  // Zero is reserved to mean "invalid".
40      table_.Put(mon_id, mon);
41      return mon_id;
42    }
43  }
44  LOG(FATAL) << "Out of internal monitor ids";
45  return 0;
46}
47
48void MonitorPool::ReleaseMonitorIdFromTable(MonitorId mon_id) {
49  WriterMutexLock mu(Thread::Current(), allocated_ids_lock_);
50  DCHECK(table_.Get(mon_id) != nullptr);
51  table_.erase(mon_id);
52  --mon_id;  // Zero is reserved to mean "invalid".
53  DCHECK(allocated_ids_[mon_id]) << mon_id;
54  allocated_ids_.reset(mon_id);
55}
56
57}  // namespace art
58