CPU profiler: make code events handling scalable.

src/circular-queue.h

 // Copyright 2010 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
@@ skipping 14 matching lines @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #ifndef V8_CIRCULAR_QUEUE_H_
 #define V8_CIRCULAR_QUEUE_H_
 
 namespace v8 {
 namespace internal {
 
 
-// Lock-based blocking circular queue for small records.  Intended for
-// transfer of small records between a single producer and a single
-// consumer. Blocks on enqueue operation if the queue is full.
-template<typename Record>
-class CircularQueue {
- public:
-  inline explicit CircularQueue(int desired_buffer_size_in_bytes);
-  inline ~CircularQueue();
-
-  INLINE(void Dequeue(Record* rec));
-  INLINE(void Enqueue(const Record& rec));
-  INLINE(bool IsEmpty()) { return enqueue_pos_ == dequeue_pos_; }
-
- private:
-  INLINE(Record* Next(Record* curr));
-
-  Record* buffer_;
-  Record* const buffer_end_;
-  Semaphore* enqueue_semaphore_;
-  Record* enqueue_pos_;
-  Record* dequeue_pos_;
-
-  DISALLOW_COPY_AND_ASSIGN(CircularQueue);
-};
-
-
 // Lock-free cache-friendly sampling circular queue for large
 // records. Intended for fast transfer of large records between a
 // single producer and a single consumer. If the queue is full,
 // previous unread records are overwritten. The queue is designed with
 // a goal in mind to evade cache lines thrashing by preventing
 // simultaneous reads and writes to adjanced memory locations.
 //
 // IMPORTANT: as a producer never checks for chunks cleanness, it is
 // possible that it can catch up and overwrite a chunk that a consumer
 // is currently reading, resulting in a corrupt record being read.
@@ skipping 49 matching lines @@
   ProducerPosition* producer_pos_;
   ConsumerPosition* consumer_pos_;
 
   DISALLOW_COPY_AND_ASSIGN(SamplingCircularQueue);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_CIRCULAR_QUEUE_H_