Tracing pre-filtering

base/trace_event/trace_config.cc

Index: base/trace_event/trace_config.cc
diff --git a/base/trace_event/trace_config.cc b/base/trace_event/trace_config.cc
index 25a0cd6d40b5d7aee19c68a9eb06a54f2c665bd5..16e1232846bef3d4e0a28274dc3e722cd9fefce9 100644
--- a/base/trace_event/trace_config.cc
+++ b/base/trace_event/trace_config.cc
@@ -53,6 +53,11 @@ const char kModeParam[] = "mode";
 const char kHeapProfilerOptions[] = "heap_profiler_options";
 const char kBreakdownThresholdBytes[] = "breakdown_threshold_bytes";
 
+// String parameters used to parse category event filters.
+const char kEventFiltersParam[] = "event_filters";
+const char kFilterPredicateParam[] = "filter_predicate";
+const char kFilterArgsParam[] = "filter_args";
+
 // Default configuration of memory dumps.
 const TraceConfig::MemoryDumpConfig::Trigger kDefaultHeavyMemoryDumpTrigger = {
     2000,  // periodic_interval_ms
@@ -66,7 +71,9 @@ class ConvertableTraceConfigToTraceFormat
  public:
   explicit ConvertableTraceConfigToTraceFormat(const TraceConfig& trace_config)
       : trace_config_(trace_config) {}
+
   ~ConvertableTraceConfigToTraceFormat() override {}
+
   void AppendAsTraceFormat(std::string* out) const override {
     out->append(trace_config_.ToString());
   }
@@ -97,6 +104,74 @@ void TraceConfig::MemoryDumpConfig::Clear() {
   heap_profiler_options.Clear();
 }
 
+TraceConfig::EventFilterConfig::EventFilterConfig(
+    const std::string& predicate_name)
+    : predicate_name_(predicate_name) {}
+TraceConfig::EventFilterConfig::~EventFilterConfig() {}
+
+TraceConfig::EventFilterConfig::EventFilterConfig(const EventFilterConfig& tc)
+    : predicate_name_(tc.predicate_name_),
+      included_categories_(tc.included_categories_),
+      excluded_categories_(tc.excluded_categories_) {
+  if (tc.args_)
+    args_ = tc.args_->CreateDeepCopy();

[Primiano Tucci (use gerrit), 2016/05/27 17:47:06]

I wonder, can you just say *this = tc here and reuse the code from the =
operator, instead of duping it?

[oystein (OOO til 10th of July), 2016/08/01 13:39:48]

Done.

+}
+
+TraceConfig::EventFilterConfig& TraceConfig::EventFilterConfig::operator=(
+    const TraceConfig::EventFilterConfig& rhs) {
+  if (this == &rhs)
+    return *this;
+
+  predicate_name_ = rhs.predicate_name_;
+  included_categories_ = rhs.included_categories_;
+  excluded_categories_ = rhs.excluded_categories_;
+  if (rhs.args_)
+    args_ = rhs.args_->CreateDeepCopy();
+
+  return *this;
+}
+
+void TraceConfig::EventFilterConfig::AddIncludedCategory(
+    const std::string& category) {
+  included_categories_.push_back(category);
+}
+
+void TraceConfig::EventFilterConfig::AddExcludedCategory(
+    const std::string& category) {
+  excluded_categories_.push_back(category);
+}
+
+void TraceConfig::EventFilterConfig::SetArgs(
+    std::unique_ptr<base::DictionaryValue> args) {
+  args_ = std::move(args);
+}
+
+bool TraceConfig::EventFilterConfig::IsCategoryGroupEnabled(
+    const char* category_group_name) const {
+  CStringTokenizer category_group_tokens(
+      category_group_name, category_group_name + strlen(category_group_name),
+      ",");
+  while (category_group_tokens.GetNext()) {
+    std::string category_group_token = category_group_tokens.token();
+
+    for (const auto& excluded_category : excluded_categories_) {
+      if (base::MatchPattern(category_group_token.c_str(),

[Primiano Tucci (use gerrit), 2016/05/27 17:47:06]

nit: i think you dont' need c_str as StringPiece has an implicit ctor from
std::string.

[oystein (OOO til 10th of July), 2016/08/01 13:39:48]

Done.

+                             excluded_category.c_str())) {
+        return false;
+      }
+    }
+
+    for (const auto& included_category : included_categories_) {
+      if (base::MatchPattern(category_group_token.c_str(),
+                             included_category.c_str())) {
+        return true;
+      }
+    }
+  }
+
+  return false;
+}
+
 TraceConfig::TraceConfig() {
   InitializeDefault();
 }
@@ -148,7 +223,8 @@ TraceConfig::TraceConfig(const TraceConfig& tc)
       included_categories_(tc.included_categories_),
       disabled_categories_(tc.disabled_categories_),
       excluded_categories_(tc.excluded_categories_),
-      synthetic_delays_(tc.synthetic_delays_) {}
+      synthetic_delays_(tc.synthetic_delays_),
+      event_filters_(tc.event_filters_) {}
 
 TraceConfig::~TraceConfig() {
 }
@@ -166,6 +242,7 @@ TraceConfig& TraceConfig::operator=(const TraceConfig& rhs) {
   disabled_categories_ = rhs.disabled_categories_;
   excluded_categories_ = rhs.excluded_categories_;
   synthetic_delays_ = rhs.synthetic_delays_;
+  event_filters_ = rhs.event_filters_;
   return *this;
 }
 
@@ -304,6 +381,7 @@ void TraceConfig::Clear() {
   excluded_categories_.clear();
   synthetic_delays_.clear();
   memory_dump_config_.Clear();
+  event_filters_.clear();
 }
 
 void TraceConfig::InitializeDefault() {
@@ -365,6 +443,10 @@ void TraceConfig::InitializeFromConfigDict(const DictionaryValue& dict) {
     else
       SetDefaultMemoryDumpConfig();
   }
+
+  const base::ListValue* category_event_filters = nullptr;
+  if (dict.GetList(kEventFiltersParam, &category_event_filters))
+    SetEventFilters(*category_event_filters);
 }
 
 void TraceConfig::InitializeFromConfigString(const std::string& config_string) {
@@ -561,6 +643,51 @@ void TraceConfig::SetDefaultMemoryDumpConfig() {
   memory_dump_config_.triggers.push_back(kDefaultLightMemoryDumpTrigger);
 }
 
+void TraceConfig::SetEventFilters(
+    const base::ListValue& category_event_filters) {
+  event_filters_.clear();
+
+  for (size_t i = 0; i < category_event_filters.GetSize(); ++i) {
+    const base::DictionaryValue* event_filter = nullptr;
+    if (!category_event_filters.GetDictionary(i, &event_filter))
+      continue;
+
+    std::string predicate_name;
+    if (!event_filter->GetString(kFilterPredicateParam, &predicate_name)) {
+      LOG(ERROR) << "Invalid predicate name in category event filter.";

[Primiano Tucci (use gerrit), 2016/05/27 17:47:06]

I might be wrong but I seem to remember that LOG (i.e. non DLOG or VLOG ) are
banned these days as they just spam chrome and nobody looks at them.
Maybe just make this a CHECK and turn it into a hard crash, people will look at
that :)

[oystein (OOO til 10th of July), 2016/08/01 13:39:48]

Done.

+      continue;
+    }
+
+    EventFilterConfig new_config(predicate_name);
+    const base::ListValue* included_list = nullptr;
+    if (!event_filter->GetList(kIncludedCategoriesParam, &included_list)) {
+      LOG(ERROR) << "Missing included_categories in category event filter.";
+      continue;
+    }
+
+    for (size_t i = 0; i < included_list->GetSize(); ++i) {

[Primiano Tucci (use gerrit), 2016/05/27 17:47:06]

note you use i outside and inside the scope. I thought we had some warning for
this. Maybe pick a different letter? :)

[oystein (OOO til 10th of July), 2016/08/01 13:39:48]

Done.

+      std::string category;
+      if (included_list->GetString(i, &category))
+        new_config.AddIncludedCategory(category);
+    }
+
+    const base::ListValue* excluded_list = nullptr;
+    if (event_filter->GetList(kExcludedCategoriesParam, &excluded_list)) {
+      for (size_t i = 0; i < excluded_list->GetSize(); ++i) {
+        std::string category;
+        if (excluded_list->GetString(i, &category))
+          new_config.AddExcludedCategory(category);
+      }
+    }
+
+    const base::DictionaryValue* args_dict = nullptr;
+    if (event_filter->GetDictionary(kFilterArgsParam, &args_dict))
+      new_config.SetArgs(args_dict->CreateDeepCopy());
+
+    event_filters_.push_back(new_config);
+  }
+}
+
 void TraceConfig::ToDict(base::DictionaryValue& dict) const {
   switch (record_mode_) {
     case RECORD_UNTIL_FULL:
@@ -602,6 +729,41 @@ void TraceConfig::ToDict(base::DictionaryValue& dict) const {
   AddCategoryToDict(dict, kExcludedCategoriesParam, excluded_categories_);
   AddCategoryToDict(dict, kSyntheticDelaysParam, synthetic_delays_);
 
+  if (!event_filters_.empty()) {
+    std::unique_ptr<base::ListValue> filter_list(new base::ListValue());
+    for (const EventFilterConfig& filter : event_filters_) {
+      std::unique_ptr<base::DictionaryValue> filter_dict(
+          new base::DictionaryValue());
+      filter_dict->SetString(kFilterPredicateParam, filter.predicate_name());
+
+      std::unique_ptr<base::ListValue> included_categories_list(
+          new base::ListValue());
+      for (const std::string& included_category : filter.included_categories())
+        included_categories_list->AppendString(included_category);
+
+      filter_dict->Set(kIncludedCategoriesParam,
+                       std::move(included_categories_list));
+
+      if (!filter.excluded_categories().empty()) {
+        std::unique_ptr<base::ListValue> excluded_categories_list(
+            new base::ListValue());
+        for (const std::string& excluded_category :
+             filter.excluded_categories())
+          excluded_categories_list->AppendString(excluded_category);
+
+        filter_dict->Set(kExcludedCategoriesParam,
+                         std::move(excluded_categories_list));
+      }
+
+      if (filter.filter_args())
+        filter_dict->Set(kFilterArgsParam,
+                         filter.filter_args()->CreateDeepCopy());
+
+      filter_list->Append(std::move(filter_dict));
+    }
+    dict.Set(kEventFiltersParam, std::move(filter_list));
+  }
+
   if (IsCategoryEnabled(MemoryDumpManager::kTraceCategory)) {
     std::unique_ptr<base::DictionaryValue> memory_dump_config(
         new base::DictionaryValue());