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diff --git a/tensorflow/compiler/xla/service/gpu/xfeed_queue.h b/tensorflow/compiler/xla/service/gpu/xfeed_queue.h
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+/* Copyright 2018 The TensorFlow Authors. All Rights Reserved.
+
+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 TENSORFLOW_COMPILER_XLA_SERVICE_GPU_XFEED_QUEUE_H_
+#define TENSORFLOW_COMPILER_XLA_SERVICE_GPU_XFEED_QUEUE_H_
+
+#include <deque>
+#include <functional>
+#include <vector>
+
+#include "tensorflow/core/platform/mutex.h"
+#include "tensorflow/core/platform/notification.h"
+#include "tensorflow/core/platform/thread_annotations.h"
+
+namespace xla {
+namespace gpu {
+
+// TODO(b/30467474) Once GPU outfeed implementation settles, consider
+// folding back the cpu and gpu outfeed implementations into a generic
+// one if possible.
+
+// Manages a thread-safe queue of buffers.
+template <typename BufferType>
+class XfeedQueue {
+ public:
+  // Adds a tree of buffers to the queue. The individual buffers correspond to
+  // the elements of a tuple and may be nullptr if the buffer is a tuple index
+  // buffer.
+  void EnqueueDestination(BufferType buffers) {
+    tensorflow::mutex_lock l(mu_);
+    enqueued_buffers_.push_back(std::move(buffers));
+    cv_.notify_one();
+  }
+
+  // Blocks until the queue is non-empty, then returns the buffer at the head of
+  // the queue.
+  BufferType BlockingGetNextDestination() {
+    bool became_empty;
+    BufferType current_buffer;
+    {
+      tensorflow::mutex_lock l(mu_);
+      while (enqueued_buffers_.empty()) {
+        cv_.wait(l);
+      }
+      current_buffer = std::move(enqueued_buffers_.front());
+      enqueued_buffers_.pop_front();
+      became_empty = enqueued_buffers_.empty();
+    }
+    if (became_empty) {
+      for (const auto& callback : on_empty_callbacks_) {
+        callback();
+      }
+    }
+    return current_buffer;
+  }
+
+  void RegisterOnEmptyCallback(std::function<void()> callback) {
+    on_empty_callbacks_.push_back(std::move(callback));
+  }
+
+ private:
+  tensorflow::mutex mu_;
+
+  // Condition variable that is signaled every time a buffer is enqueued.
+  tensorflow::condition_variable cv_;
+
+  // The queue of trees of buffers. Buffer* queue contents are not owned.
+  std::deque<BufferType> enqueued_buffers_ GUARDED_BY(mu_);
+
+  // List of callbacks which will be called when 'enqueued_buffers_' becomes
+  // empty.
+  std::vector<std::function<void()>> on_empty_callbacks_;
+};
+
+}  // namespace gpu
+}  // namespace xla
+
+#endif  // TENSORFLOW_COMPILER_XLA_SERVICE_GPU_XFEED_QUEUE_H_