1 /* 2 * Copyright (C) 2012 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_BARRIER_H_ 18 #define ART_RUNTIME_BARRIER_H_ 19 20 #include <memory> 21 #include "base/mutex.h" 22 23 namespace art { 24 25 class Barrier { 26 public: 27 explicit Barrier(int count); 28 virtual ~Barrier(); 29 30 // Pass through the barrier, decrements the count but does not block. 31 void Pass(Thread* self); 32 33 // Wait on the barrier, decrement the count. 34 void Wait(Thread* self); 35 36 // Set the count to a new value, if the value is 0 then everyone waiting on the condition 37 // variable is resumed. 38 void Init(Thread* self, int count); 39 40 // Increment the count by delta, wait on condition if count is non zero. 41 void Increment(Thread* self, int delta); 42 43 // Increment the count by delta, wait on condition if count is non zero, with a timeout 44 void Increment(Thread* self, int delta, uint32_t timeout_ms) LOCKS_EXCLUDED(lock_); 45 46 private: 47 void SetCountLocked(Thread* self, int count) EXCLUSIVE_LOCKS_REQUIRED(lock_); 48 49 // Counter, when this reaches 0 all people blocked on the barrier are signalled. 50 int count_ GUARDED_BY(lock_); 51 52 Mutex lock_ DEFAULT_MUTEX_ACQUIRED_AFTER; 53 ConditionVariable condition_ GUARDED_BY(lock_); 54 }; 55 56 } // namespace art 57 #endif // ART_RUNTIME_BARRIER_H_ 58