diff --git a/src/circular-queue-inl.h b/src/circular-queue-inl.h
index 373bf60..2f06f6c 100644
--- a/src/circular-queue-inl.h
+++ b/src/circular-queue-inl.h
@@ -1,53 +1,69 @@
 // Copyright 2011 the V8 project authors. All rights reserved.
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-//       notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-//       copyright notice, this list of conditions and the following
-//       disclaimer in the documentation and/or other materials provided
-//       with the distribution.
-//     * Neither the name of Google Inc. nor the names of its
-//       contributors may be used to endorse or promote products derived
-//       from this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
 
 #ifndef V8_CIRCULAR_QUEUE_INL_H_
 #define V8_CIRCULAR_QUEUE_INL_H_
 
-#include "circular-queue.h"
+#include "src/circular-queue.h"
 
 namespace v8 {
 namespace internal {
 
-
-void* SamplingCircularQueue::Enqueue() {
-  WrapPositionIfNeeded(&producer_pos_->enqueue_pos);
-  void* result = producer_pos_->enqueue_pos;
-  producer_pos_->enqueue_pos += record_size_;
-  return result;
+template<typename T, unsigned L>
+SamplingCircularQueue<T, L>::SamplingCircularQueue()
+    : enqueue_pos_(buffer_),
+      dequeue_pos_(buffer_) {
 }
 
 
-void SamplingCircularQueue::WrapPositionIfNeeded(
-    SamplingCircularQueue::Cell** pos) {
-  if (**pos == kEnd) *pos = buffer_;
+template<typename T, unsigned L>
+SamplingCircularQueue<T, L>::~SamplingCircularQueue() {
 }
 
 
+template<typename T, unsigned L>
+T* SamplingCircularQueue<T, L>::Peek() {
+  base::MemoryBarrier();
+  if (base::Acquire_Load(&dequeue_pos_->marker) == kFull) {
+    return &dequeue_pos_->record;
+  }
+  return NULL;
+}
+
+
+template<typename T, unsigned L>
+void SamplingCircularQueue<T, L>::Remove() {
+  base::Release_Store(&dequeue_pos_->marker, kEmpty);
+  dequeue_pos_ = Next(dequeue_pos_);
+}
+
+
+template<typename T, unsigned L>
+T* SamplingCircularQueue<T, L>::StartEnqueue() {
+  base::MemoryBarrier();
+  if (base::Acquire_Load(&enqueue_pos_->marker) == kEmpty) {
+    return &enqueue_pos_->record;
+  }
+  return NULL;
+}
+
+
+template<typename T, unsigned L>
+void SamplingCircularQueue<T, L>::FinishEnqueue() {
+  base::Release_Store(&enqueue_pos_->marker, kFull);
+  enqueue_pos_ = Next(enqueue_pos_);
+}
+
+
+template<typename T, unsigned L>
+typename SamplingCircularQueue<T, L>::Entry* SamplingCircularQueue<T, L>::Next(
+    Entry* entry) {
+  Entry* next = entry + 1;
+  if (next == &buffer_[L]) return buffer_;
+  return next;
+}
+
 } }  // namespace v8::internal
 
 #endif  // V8_CIRCULAR_QUEUE_INL_H_