From 48c8ed422c4d35bbbc8a3e8e137e5c778ac0e441 Mon Sep 17 00:00:00 2001
From: Mikhail Atuchin <matuchin@brave.com>
Date: Tue, 10 Oct 2023 01:15:54 +0100
Subject: [PATCH] Add adblock loading traces & UMAs

---
 .../browser/dat_file_util.cc                  |  6 +++-
 .../brave_shields/browser/ad_block_engine.cc  | 35 ++++++++++++++++++-
 2 files changed, 39 insertions(+), 2 deletions(-)

diff --git a/components/brave_component_updater/browser/dat_file_util.cc b/components/brave_component_updater/browser/dat_file_util.cc
index 9376d9db8850..ce8c9f55e8db 100644
--- a/components/brave_component_updater/browser/dat_file_util.cc
+++ b/components/brave_component_updater/browser/dat_file_util.cc
@@ -8,9 +8,10 @@
 #include <memory>
 #include <string>
 
-#include "base/logging.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
+#include "base/logging.h"
+#include "base/trace_event/trace_event.h"
 
 namespace {
 
@@ -40,8 +41,11 @@ void GetDATFileData(const base::FilePath& file_path,
 namespace brave_component_updater {
 
 DATFileDataBuffer ReadDATFileData(const base::FilePath& dat_file_path) {
+  TRACE_EVENT_BEGIN1("brave.adblock", "ReadDATFileData", "path",
+                     dat_file_path.MaybeAsASCII());
   DATFileDataBuffer buffer;
   GetDATFileData(dat_file_path, &buffer);
+  TRACE_EVENT_END1("brave.adblock", "ReadDATFileData", "size", buffer.size());
   return buffer;
 }
 
diff --git a/components/brave_shields/browser/ad_block_engine.cc b/components/brave_shields/browser/ad_block_engine.cc
index 5aa3f42b6551..7512329e3551 100644
--- a/components/brave_shields/browser/ad_block_engine.cc
+++ b/components/brave_shields/browser/ad_block_engine.cc
@@ -12,7 +12,10 @@
 
 #include "base/containers/contains.h"
 #include "base/json/json_reader.h"
+#include "base/metrics/histogram_functions.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/timer/elapsed_timer.h"
+#include "base/trace_event/trace_event.h"
 #include "net/base/registry_controlled_domains/registry_controlled_domain.h"
 #include "url/origin.h"
 
@@ -243,6 +246,7 @@ base::Value::List AdBlockEngine::HiddenClassIdSelectors(
 void AdBlockEngine::Load(bool deserialize,
                          const DATFileDataBuffer& dat_buf,
                          const std::string& resources_json) {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
   if (deserialize) {
     OnDATLoaded(dat_buf, resources_json);
   } else {
@@ -275,7 +279,21 @@ void AdBlockEngine::AddKnownTagsToAdBlockInstance() {
 
 void AdBlockEngine::OnListSourceLoaded(const DATFileDataBuffer& filters,
                                        const std::string& resources_json) {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+
+  base::ElapsedTimer timer;
+  TRACE_EVENT_BEGIN1("brave.adblock", "MakeEngineWithRules", "size",
+                     filters.size());
+
   auto result = adblock::engine_with_rules(filters);
+
+  TRACE_EVENT_END0("brave.adblock", "MakeEngineWithRules");
+  base::UmaHistogramTimes("Brave.Adblock.MakeEngineWithRules", timer.Elapsed());
+  if (filters.size() > 10'000) {
+    base::UmaHistogramTimes("Brave.Adblock.MakeEngineWithRules.Large",
+                            timer.Elapsed());
+  }
+
   if (result.result_kind != adblock::ResultKind::Success) {
     LOG(ERROR) << "AdBlockEngine::OnListSourceLoaded failed: "
                << result.error_message.c_str();
@@ -286,13 +304,28 @@ void AdBlockEngine::OnListSourceLoaded(const DATFileDataBuffer& filters,
 
 void AdBlockEngine::OnDATLoaded(const DATFileDataBuffer& dat_buf,
                                 const std::string& resources_json) {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+
   // An empty buffer will not load successfully.
   if (dat_buf.empty()) {
     return;
   }
 
+  base::ElapsedTimer timer;
+  TRACE_EVENT_BEGIN1("brave.adblock", "EngineDeserialize", "size",
+                     dat_buf.size());
+
   auto client = adblock::new_engine();
-  if (!client->deserialize(dat_buf)) {
+  const auto result = client->deserialize(dat_buf);
+
+  TRACE_EVENT_END0("brave.adblock", "EngineDeserialize");
+  base::UmaHistogramTimes("Brave.Adblock.EngineDeserialize", timer.Elapsed());
+  if (dat_buf.size() > 10'000) {
+    base::UmaHistogramTimes("Brave.Adblock.EngineDeserialize.Large",
+                            timer.Elapsed());
+  }
+
+  if (!result) {
     LOG(ERROR) << "AdBlockEngine::OnDATLoaded deserialize failed";
     return;
   }