1 files changed, 55 insertions, 0 deletions
diff --git a/runtime/barrier.h b/runtime/barrier.h
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+++ b/runtime/barrier.h
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+/*
+ * Copyright (C) 2012 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.
+ */
+
+#ifndef ART_SRC_BARRIER_H_
+#define ART_SRC_BARRIER_H_
+
+#include "base/mutex.h"
+#include "locks.h"
+#include "UniquePtr.h"
+
+namespace art {
+
+class Barrier {
+ public:
+  Barrier(int count);
+  virtual ~Barrier();
+
+  // Pass through the barrier, decrements the count but does not block.
+  void Pass(Thread* self);
+
+  // Wait on the barrier, decrement the count.
+  void Wait(Thread* self);
+
+  // Set the count to a new value, if the value is 0 then everyone waiting on the condition
+  // variable is resumed.
+  void Init(Thread* self, int count);
+
+  // Increment the count by delta, wait on condition if count is non zero.
+  void Increment(Thread* self, int delta);
+
+ private:
+  void SetCountLocked(Thread* self, int count) EXCLUSIVE_LOCKS_REQUIRED(lock_);
+
+  // Counter, when this reaches 0 all people blocked on the barrier are signalled.
+  int count_ GUARDED_BY(lock_);
+
+  Mutex lock_ DEFAULT_MUTEX_ACQUIRED_AFTER;
+  ConditionVariable condition_ GUARDED_BY(lock_);
+};
+
+}  // namespace art
+#endif  // ART_SRC_GC_BARRIER_H_