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diff --git a/tools/performance/Perfetto.h b/tools/performance/Perfetto.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_Perfetto_h
+#define mozilla_Perfetto_h
+
+#ifdef MOZ_PERFETTO
+#  include "perfetto/perfetto.h"
+#  include "mozilla/TimeStamp.h"
+
+// Initialization is called when a content process is created.
+// This can be called multiple times.
+extern void InitPerfetto();
+
+/* Perfetto Tracing:
+ *
+ * This file provides an interface to the perfetto tracing API.  The API from
+ * the perfetto sdk can be used directly, but an additional set of macros
+ * prefixed with PERFETTO_* have been defined to help minimize the use of
+ * ifdef's.
+ *
+ * The common perfetto macros require a category and name at the very least.
+ * These must be static strings, or wrapped with perfetto::DynamicString if
+ * dynamic. If the string is static, but provided through a runtime pointer,
+ * then it must be wrapped with perfetto::StaticString.
+ *
+ * You can also provide additional parameters such as a timestamp,
+ * or a lambda to add additional information to the trace marker.
+ * For more info, see https://perfetto.dev/docs/instrumentation/tracing-sdk
+ *
+ * Examples:
+ *
+ *  // Add a trace event to measure work inside a block,
+ *  // using static strings only.
+ *
+ *  {
+ *    PERFETTO_TRACE_EVENT("js", "JS::RunScript");
+ *    run_script();
+ *  }
+ *
+ *  // Add a trace event to measure work inside a block,
+ *  // using a dynamic string.
+ *
+ *  void runScript(nsCString& scriptName)
+ *  {
+ *    PERFETTO_TRACE_EVENT("js", perfetto::DynamicString{scriptName.get()});
+ *    run_script();
+ *  }
+ *
+ *  // Add a trace event using a dynamic category and name.
+ *
+ *  void runScript(nsCString& categoryName, nsCString& scriptName)
+ *  {
+ *    perfetto::DynamicCategory category{category.get()};
+ *    PERFETTO_TRACE_EVENT(category, perfetto::DynamicString{scriptName.get()});
+ *    run_script();
+ *  }
+ *
+ *  // Add a trace event to measure two arbitrary points of code.
+ *  // Events in the same category must always be nested.
+ *
+ *  void startWork() {
+ *    PERFETTO_TRACE_EVENT_BEGIN("js", "StartWork");
+ *    ...
+ *    PERFETTO_TRACE_EVENT_END("js");
+ *  }
+ *
+ *  // Create a trace marker for an event that has already occurred
+ *  // using previously saved timestamps.
+ *
+ *  void record_event(TimeStamp startTimeStamp, TimeStamp endTimeStamp)
+ *  {
+ *    PERFETTO_TRACE_EVENT_BEGIN("js", "Some Event", startTimeStamp);
+ *    PERFETTO_TRACE_EVENT_END("js", endTimeStamp);
+ *  }
+ */
+
+// Wrap the common trace event macros from perfetto so
+// they can be called without #ifdef's.
+#  define PERFETTO_TRACE_EVENT(...) TRACE_EVENT(__VA_ARGS__)
+#  define PERFETTO_TRACE_EVENT_BEGIN(...) TRACE_EVENT_BEGIN(__VA_ARGS__)
+#  define PERFETTO_TRACE_EVENT_END(...) TRACE_EVENT_END(__VA_ARGS__)
+
+namespace perfetto {
+// Specialize custom timestamps for mozilla::TimeStamp.
+template <>
+struct TraceTimestampTraits<mozilla::TimeStamp> {
+  static inline TraceTimestamp ConvertTimestampToTraceTimeNs(
+      const mozilla::TimeStamp& timestamp) {
+    return {protos::gen::BuiltinClock::BUILTIN_CLOCK_MONOTONIC,
+            timestamp.RawClockMonotonicNanosecondsSinceBoot()};
+  }
+};
+}  // namespace perfetto
+
+// Categories can be added dynamically, but to minimize overhead
+// all categories should be pre-defined here whenever possible.
+PERFETTO_DEFINE_CATEGORIES(perfetto::Category("task"),
+                           perfetto::Category("usertiming"));
+
+#else  // !defined(MOZ_PERFETTO)
+#  define PERFETTO_TRACE_EVENT(...) \
+    do {                            \
+    } while (0)
+#  define PERFETTO_TRACE_EVENT_BEGIN(...) \
+    do {                                  \
+    } while (0)
+#  define PERFETTO_TRACE_EVENT_END(...) \
+    do {                                \
+    } while (0)
+inline void InitPerfetto() {}
+#endif  // MOZ_PERFETTO
+
+#endif  // mozilla_Perfetto_h