From 89add2582d3047bf0edf4e2a1d8801e9e3361d33 Mon Sep 17 00:00:00 2001
From: Valentin Shergin <shergin@fb.com>
Date: Mon, 4 Nov 2019 18:19:05 -0800
Subject: [PATCH] Fabric: Collecting mounting time inside `MountingTelemetry`

Summary:
Now we also collect mounting time inside MountingTelemetry.
We will use it soon.

Changelog: [Internal] Fabric-specific internal change.

Reviewed By: mdvacca

Differential Revision: D18285826

fbshipit-source-id: 512fc62c210a111614b0defb0d76cbd6228fe89f
---
 React/Fabric/Mounting/RCTMountingManager.mm   |  9 ++++---
 .../fabric/mounting/MountingTelemetry.cpp     | 24 +++++++++++++++++++
 .../fabric/mounting/MountingTelemetry.h       |  6 +++++
 3 files changed, 36 insertions(+), 3 deletions(-)

diff --git a/React/Fabric/Mounting/RCTMountingManager.mm b/React/Fabric/Mounting/RCTMountingManager.mm
index f5e8317846b..709b2e302cb 100644
--- a/React/Fabric/Mounting/RCTMountingManager.mm
+++ b/React/Fabric/Mounting/RCTMountingManager.mm
@@ -269,12 +269,15 @@ static void RNPerformMountInstructions(
   }
 
   RCTAssertMainQueue();
-  auto metadata = MountingTransactionMetadata{surfaceId, transaction->getNumber(), transaction->getTelemetry()};
+  auto telemetry = transaction->getTelemetry();
+  auto number = transaction->getNumber();
 
   [self.delegate mountingManager:self willMountComponentsWithRootTag:surfaceId];
-  _observerCoordinator.notifyObserversMountingTransactionWillMount(metadata);
+  _observerCoordinator.notifyObserversMountingTransactionWillMount({surfaceId, number, telemetry});
+  telemetry.willMount();
   RNPerformMountInstructions(mutations, self.componentViewRegistry, _observerCoordinator, surfaceId);
-  _observerCoordinator.notifyObserversMountingTransactionDidMount(metadata);
+  telemetry.didMount();
+  _observerCoordinator.notifyObserversMountingTransactionDidMount({surfaceId, number, telemetry});
   [self.delegate mountingManager:self didMountComponentsWithRootTag:surfaceId];
 }
 
diff --git a/ReactCommon/fabric/mounting/MountingTelemetry.cpp b/ReactCommon/fabric/mounting/MountingTelemetry.cpp
index f96e4b1d292..a3f2f8bc2b7 100644
--- a/ReactCommon/fabric/mounting/MountingTelemetry.cpp
+++ b/ReactCommon/fabric/mounting/MountingTelemetry.cpp
@@ -51,6 +51,18 @@ void MountingTelemetry::didLayout() {
   layoutEndTime_ = monotonicTimeInMilliseconds();
 }
 
+void MountingTelemetry::willMount() {
+  assert(mountStartTime_ == kUndefinedTime);
+  assert(mountEndTime_ == kUndefinedTime);
+  mountStartTime_ = monotonicTimeInMilliseconds();
+}
+
+void MountingTelemetry::didMount() {
+  assert(mountStartTime_ != kUndefinedTime);
+  assert(mountEndTime_ == kUndefinedTime);
+  mountEndTime_ = monotonicTimeInMilliseconds();
+}
+
 int64_t MountingTelemetry::getDiffStartTime() const {
   assert(diffStartTime_ != kUndefinedTime);
   assert(diffEndTime_ != kUndefinedTime);
@@ -91,5 +103,17 @@ int64_t MountingTelemetry::getLayoutEndTime() const {
   return layoutEndTime_;
 }
 
+int64_t MountingTelemetry::getMountStartTime() const {
+  assert(mountStartTime_ != kUndefinedTime);
+  assert(mountEndTime_ != kUndefinedTime);
+  return mountStartTime_;
+}
+
+int64_t MountingTelemetry::getMountEndTime() const {
+  assert(mountStartTime_ != kUndefinedTime);
+  assert(mountEndTime_ != kUndefinedTime);
+  return mountEndTime_;
+}
+
 } // namespace react
 } // namespace facebook
diff --git a/ReactCommon/fabric/mounting/MountingTelemetry.h b/ReactCommon/fabric/mounting/MountingTelemetry.h
index aa2062cf1e9..97735a10c47 100644
--- a/ReactCommon/fabric/mounting/MountingTelemetry.h
+++ b/ReactCommon/fabric/mounting/MountingTelemetry.h
@@ -28,6 +28,8 @@ class MountingTelemetry final {
   void didCommit();
   void willLayout();
   void didLayout();
+  void willMount();
+  void didMount();
 
   /*
    * Reading
@@ -39,6 +41,8 @@ class MountingTelemetry final {
   int64_t getCommitStartTime() const;
   int64_t getCommitEndTime() const;
   int64_t getCommitNumber() const;
+  int64_t getMountStartTime() const;
+  int64_t getMountEndTime() const;
 
  private:
   constexpr static int64_t kUndefinedTime = std::numeric_limits<int64_t>::max();
@@ -50,6 +54,8 @@ class MountingTelemetry final {
   int64_t commitEndTime_{kUndefinedTime};
   int64_t layoutStartTime_{kUndefinedTime};
   int64_t layoutEndTime_{kUndefinedTime};
+  int64_t mountStartTime_{kUndefinedTime};
+  int64_t mountEndTime_{kUndefinedTime};
 };
 
 } // namespace react