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mojo/services/tracing/tracing.mojom

Index: mojo/services/tracing/tracing.mojom
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+// Copyright 2014 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.
+
+module tracing;
+
+// To participate in the tracing ecosystem, implement the TraceController
+// interface and connect to the tracing app. Then, when the controller's Start()
+// function is called collect tracing data and pass it back via the provided
+// TraceDataCollector interface up until Stop() is called.
+
+interface TraceController {
+  StartTracing(string categories, TraceDataCollector collector);
+  StopTracing();
+};
+
+interface TraceDataCollector {
+  DataCollected(string json);
+};
+
+interface TraceCoordinator {
+  // Request tracing data from all connected TraceControllers to stream to
+  // |stream|.
+  Start(handle<data_pipe_producer> stream, string categories);
+
+  // Stop tracing and flush results to file.
+  StopAndFlush();
+};