Add systrace support in Fabric C++

Summary: This diff adds systrace support in the C++ side of Fabric

Reviewed By: ejanzer

Differential Revision: D12861373

fbshipit-source-id: 0291f3e406f239bbef3686ac0bba6e9f1c7eac57

Author: mdvacca

ReactCommon/fabric/debug/SystraceSection.h

@@ -0,0 +1,49 @@
+// Copyright (c) Facebook, Inc. and its affiliates.
+
+// This source code is licensed under the MIT license found in the
+// LICENSE file in the root directory of this source tree.
+
+#pragma once
+
+#ifdef WITH_FBSYSTRACE
+#include <fbsystrace.h>
+#endif
+
+namespace facebook {
+namespace react {
+
+/**
+ * This is a convenience class to avoid lots of verbose profiling
+ * #ifdefs.  If WITH_FBSYSTRACE is not defined, the optimizer will
+ * remove this completely.  If it is defined, it will behave as
+ * FbSystraceSection, with the right tag provided. Use two separate classes to
+ * to ensure that the ODR rule isn't violated, that is, if WITH_FBSYSTRACE has
+ * different values in different files, there is no inconsistency in the sizes
+ * of defined symbols.
+ */
+#ifdef WITH_FBSYSTRACE
+struct ConcreteSystraceSection {
+ public:
+  template <typename... ConvertsToStringPiece>
+  explicit ConcreteSystraceSection(
+      const char *name,
+      ConvertsToStringPiece &&... args)
+      : m_section(TRACE_TAG_REACT_CXX_BRIDGE, name, args...) {}
+
+ private:
+  fbsystrace::FbSystraceSection m_section;
+};
+using SystraceSection = ConcreteSystraceSection;
+#else
+struct DummySystraceSection {
+ public:
+  template <typename... ConvertsToStringPiece>
+  explicit DummySystraceSection(
+      const char *name,
+      ConvertsToStringPiece &&... args) {}
+};
+using SystraceSection = DummySystraceSection;
+#endif
+
+} // namespace react
+} // namespace facebook

ReactCommon/fabric/events/EventEmitter.cpp

@@ -7,6 +7,7 @@
 
 #include "EventEmitter.h"
 
+#include <fabric/debug/SystraceSection.h>
 #include <folly/dynamic.h>
 
 #include "RawEvent.h"
@@ -46,6 +47,7 @@ void EventEmitter::dispatchEvent(
     const std::string &type,
     const folly::dynamic &payload,
     const EventPriority &priority) const {
+  SystraceSection s("EventEmitter::dispatchEvent");
   auto eventDispatcher = eventDispatcher_.lock();
   if (!eventDispatcher) {
     return;

ReactCommon/fabric/uimanager/UIManager.cpp

@@ -3,6 +3,7 @@
 #include "UIManager.h"
 
 #include <fabric/core/ShadowNodeFragment.h>
+#include <fabric/debug/SystraceSection.h>
 
 namespace facebook {
 namespace react {
@@ -60,6 +61,7 @@ void UIManager::appendChild(
 void UIManager::completeSurface(
     SurfaceId surfaceId,
     const SharedShadowNodeUnsharedList &rootChildren) const {
+  SystraceSection s("FabricUIManager::completeSurface");
   if (delegate_) {
     delegate_->uiManagerDidFinishTransaction(surfaceId, rootChildren);
   }

ReactCommon/fabric/uimanager/UIManagerBinding.cpp

@@ -2,6 +2,8 @@
 
 #include "UIManagerBinding.h"
 
+#include <fabric/debug/SystraceSection.h>
+
 #include <jsi/JSIDynamic.h>
 
 namespace facebook {
@@ -69,6 +71,7 @@ void UIManagerBinding::dispatchEvent(
   auto eventTargetValue = jsi::Value::null();
 
   if (eventTarget) {
+    SystraceSection s("UIManagerBinding::JSIDispatchFabricEventToTarget");
     auto &eventTargetWrapper =
         static_cast<const EventTargetWrapper &>(*eventTarget);
     eventTargetValue = eventTargetWrapper.instanceHandle.lock(runtime);