Trace-based benchmarking via a mojo app.

apps/benchmark/measurements.h

Index: apps/benchmark/measurements.h
diff --git a/apps/benchmark/measurements.h b/apps/benchmark/measurements.h
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+// Copyright 2015 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 APPS_BENCHMARK_MEASUREMENTS_HH_
+#define APPS_BENCHMARK_MEASUREMENTS_HH_
+
+#include <vector>
+
+#include "apps/benchmark/event.h"
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/time/time.h"
+#include "base/values.h"
+
+namespace benchmark {
+
+// Describes a trace event to match.
+struct EventSpec {
+  std::string name;
+  std::string category;
+};
+
+// Represents a single measurement to be performed on the collected trace.
+struct Measurement {
+  enum MeasurementType { TIME_UNTIL, AVG_DURATION };
+
+  MeasurementType type;
+  EventSpec target_event;
+  std::string spec;
+};
+
+class Measurements {
+ public:
+  Measurements(std::vector<Event> events, EventSpec reference_spec);
+  ~Measurements();
+
+  double Measure(const Measurement& measurement);
+
+ private:
+  double TimeUntil(const EventSpec& event_spec);
+  double AvgDuration(const EventSpec& event_spec);
+
+  base::TimeTicks FindEarliest(const EventSpec& spec);
+
+  std::vector<Event> events_;
+  EventSpec reference_spec_;
+  DISALLOW_COPY_AND_ASSIGN(Measurements);
+};
+
+}  // namespace benchmark
+
+#endif  // APPS_BENCHMARK_MEASUREMENTS_HH_