From 5a22d0be5050bb08ff3dbc9fd09c049bf8b4d0a1 Mon Sep 17 00:00:00 2001
From: chaopeng <chaopeng@chaopeng.me>
Date: Mon, 18 Mar 2024 18:51:31 -0400
Subject: [PATCH] [Fuchsia] Support per app present latency tracing

Bug: http://b/323408867
---
 shell/platform/fuchsia/flutter/flatland_connection.cc | 6 +++++-
 shell/platform/fuchsia/flutter/flatland_connection.h  | 1 +
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/shell/platform/fuchsia/flutter/flatland_connection.cc b/shell/platform/fuchsia/flutter/flatland_connection.cc
index cfc7ea0923455..6a45b8b44e83c 100644
--- a/shell/platform/fuchsia/flutter/flatland_connection.cc
+++ b/shell/platform/fuchsia/flutter/flatland_connection.cc
@@ -33,6 +33,7 @@ FlatlandConnection::FlatlandConnection(
     FML_LOG(ERROR) << "Flatland disconnected: " << zx_status_get_string(status);
     callback();
   });
+  debug_label_ = debug_label;
   flatland_->SetDebugName(debug_label);
   flatland_.events().OnError =
       fit::bind_member(this, &FlatlandConnection::OnError);
@@ -58,7 +59,10 @@ void FlatlandConnection::Present() {
 // This method is called from the raster thread.
 void FlatlandConnection::DoPresent() {
   TRACE_DURATION("flutter", "FlatlandConnection::DoPresent");
-  TRACE_FLOW_BEGIN("gfx", "Flatland::Present", next_present_trace_id_);
+
+  std::string per_app_tracing_name =
+      "Flatland::PerAppPresent[" + debug_label_ + "]";
+  TRACE_FLOW_BEGIN("gfx", per_app_tracing_name.c_str(), next_present_trace_id_);
   ++next_present_trace_id_;
 
   FML_CHECK(threadsafe_state_.present_credits_ > 0);
diff --git a/shell/platform/fuchsia/flutter/flatland_connection.h b/shell/platform/fuchsia/flutter/flatland_connection.h
index 87020058db6df..59c67e14f430e 100644
--- a/shell/platform/fuchsia/flutter/flatland_connection.h
+++ b/shell/platform/fuchsia/flutter/flatland_connection.h
@@ -105,6 +105,7 @@ class FlatlandConnection final {
   std::vector<zx::event> acquire_fences_;
   std::vector<zx::event> current_present_release_fences_;
   std::vector<zx::event> previous_present_release_fences_;
+  std::string debug_label_;
 
   FML_DISALLOW_COPY_AND_ASSIGN(FlatlandConnection);
 };