1 /* 2 * Copyright (C) 2011 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_INTERPRETER_LOCK_COUNT_DATA_H_ 18 #define ART_RUNTIME_INTERPRETER_LOCK_COUNT_DATA_H_ 19 20 #include <memory> 21 #include <vector> 22 23 #include "base/locks.h" 24 25 namespace art { 26 27 namespace mirror { 28 class Object; 29 } // namespace mirror 30 31 class Thread; 32 33 // Counting locks by storing object pointers into a vector. Duplicate entries mark recursive locks. 34 // The vector will be visited with the ShadowFrame during GC (so all the locked-on objects are 35 // thread roots). 36 // Note: implementation is split so that the call sites may be optimized to no-ops in case no 37 // lock counting is necessary. The actual implementation is in the cc file to avoid 38 // dependencies. 39 class LockCountData { 40 public: 41 // Add the given object to the list of monitors, that is, objects that have been locked. This 42 // will not throw (but be skipped if there is an exception pending on entry). 43 void AddMonitor(Thread* self, mirror::Object* obj) REQUIRES_SHARED(Locks::mutator_lock_); 44 45 // Try to remove the given object from the monitor list, indicating an unlock operation. 46 // This will throw an IllegalMonitorStateException (clearing any already pending exception), in 47 // case that there wasn't a lock recorded for the object. 48 void RemoveMonitorOrThrow(Thread* self, 49 const mirror::Object* obj) REQUIRES_SHARED(Locks::mutator_lock_); 50 51 // Check whether all acquired monitors have been released. This will potentially throw an 52 // IllegalMonitorStateException, clearing any already pending exception. Returns true if the 53 // check shows that everything is OK wrt/ lock counting, false otherwise. 54 bool CheckAllMonitorsReleasedOrThrow(Thread* self) REQUIRES_SHARED(Locks::mutator_lock_); 55 56 template <typename T, typename... Args> VisitMonitors(T visitor,Args &&...args)57 void VisitMonitors(T visitor, Args&&... args) REQUIRES_SHARED(Locks::mutator_lock_) { 58 if (monitors_ != nullptr) { 59 // Visitors may change the Object*. Be careful with the foreach loop. 60 for (mirror::Object*& obj : *monitors_) { 61 visitor(/* inout */ &obj, std::forward<Args>(args)...); 62 } 63 } 64 } 65 66 private: 67 // Stores references to the locked-on objects. As noted, this should be visited during thread 68 // marking. 69 std::unique_ptr<std::vector<mirror::Object*>> monitors_; 70 }; 71 72 } // namespace art 73 74 #endif // ART_RUNTIME_INTERPRETER_LOCK_COUNT_DATA_H_ 75