ui/latency/latency_tracker.h

// Copyright 2017 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_LATENCY_LATENCY_TRACKER_H_
#define UI_LATENCY_LATENCY_TRACKER_H_

#include "base/macros.h"
#include "ui/latency/latency_info.h"

namespace ui {

// Utility class for tracking the latency of events. Relies on LatencyInfo
// components logged by content::RenderWidgetHostLatencyTracker.
class LatencyTracker {
 public:
  LatencyTracker() = default;
  ~LatencyTracker() = default;

  // Terminates latency tracking for events that triggered rendering, also
  // performing relevant UMA latency reporting.
  // Called when GPU buffers swap completes.
  void OnGpuSwapBuffersCompleted(const LatencyInfo& latency);

 protected:
  virtual void ReportRapporScrollLatency(
      const std::string& name,
      const LatencyInfo::LatencyComponent& start_component,
      const LatencyInfo::LatencyComponent& end_component);

 private:
  void ComputeEndToEndLatencyHistograms(
      const LatencyInfo::LatencyComponent& gpu_swap_begin_component,
      const LatencyInfo::LatencyComponent& gpu_swap_end_component,
      const LatencyInfo& latency);

  DISALLOW_COPY_AND_ASSIGN(LatencyTracker);
};

}  // namespace latency

#endif  // UI_LATENCY_LATENCY_TRACKER_H_