Slow Reports - Add message filter to trigger background traces from child processes.

content/browser/tracing/background_tracing_manager_impl.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_TRACING_BACKGROUND_TRACING_MANAGER_IMPL_H_
 #define CONTENT_BROWSER_TRACING_BACKGROUND_TRACING_MANAGER_IMPL_H_
 
 #include "base/lazy_instance.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/metrics/histogram.h"
 #include "content/browser/tracing/tracing_controller_impl.h"
 #include "content/public/browser/background_tracing_config.h"
 #include "content/public/browser/background_tracing_manager.h"
 
 namespace content {
 
+class TraceMessageFilter;
 class TracingDelegate;
 
 class BackgroundTracingManagerImpl : public content::BackgroundTracingManager {
  public:
   static BackgroundTracingManagerImpl* GetInstance();
 
   bool SetActiveScenario(scoped_ptr<BackgroundTracingConfig>,
                          const ReceiveCallback&,
                          DataFiltering data_filtering) override;
   void WhenIdle(IdleCallback idle_callback) override;
 
   void TriggerNamedEvent(TriggerHandle, StartedFinalizingCallback) override;
   TriggerHandle RegisterTriggerType(const char* trigger_name) override;
   void GetTriggerNameList(std::vector<std::string>* trigger_names) override;
 
   void InvalidateTriggerHandlesForTesting() override;
   void SetTracingEnabledCallbackForTesting(
       const base::Closure& callback) override;
   void FireTimerForTesting() override;
   bool HasActiveScenarioForTesting() override;
 
+  void AddFilter(scoped_refptr<TraceMessageFilter> filter);
+  void RemoveFilter(scoped_refptr<TraceMessageFilter> filter);
+
+  void OnHistogramTrigger(const std::string& histogram_name) override;
+
  private:
   BackgroundTracingManagerImpl();
   ~BackgroundTracingManagerImpl() override;
 
+  void CreateDelegate();
   void EnableRecording(std::string, base::trace_event::TraceRecordMode);
   void EnableRecordingIfConfigNeedsIt();
   void OnFinalizeStarted(base::RefCountedString*);
   void OnFinalizeComplete();
   void BeginFinalizing(StartedFinalizingCallback);
   void ValidateStartupScenario();
   void AbortScenario();
 
   enum SetupUMACallMode { CLEAR_CALLBACKS, BIND_CALLBACKS };
 
   void SetupUMACallbacks(SetupUMACallMode mode);
 
-  void OnHistogramChanged(const std::string& histogram_name,
-                          base::Histogram::Sample reference_value,
-                          base::Histogram::Sample actual_value);
+  void OnHistogramChangedCallback(const std::string& histogram_name,
+                                  base::Histogram::Sample reference_value,
+                                  base::Histogram::Sample actual_value);
+  void SetupFiltersFromConfig(SetupUMACallMode mode);
+  void SetupFilterFromConfig(scoped_refptr<TraceMessageFilter> filter,
+                             SetupUMACallMode mode);
 
   scoped_ptr<base::DictionaryValue> GenerateMetadataDict() const;
 
   std::string GetTriggerNameFromHandle(TriggerHandle handle) const;
   bool IsTriggerHandleValid(TriggerHandle handle) const;
 
   bool IsAbleToTriggerTracing(TriggerHandle handle) const;
   bool IsSupportedConfig(BackgroundTracingConfig* config);
 
   std::string GetCategoryFilterStringForCategoryPreset(
       BackgroundTracingConfig::CategoryPreset) const;
 
   class TracingTimer {
    public:
     explicit TracingTimer(StartedFinalizingCallback);
     ~TracingTimer();
 
     void StartTimer();
     void CancelTimer();
 
     void FireTimerForTesting();
 
    private:
     void TracingTimerFired();
 
     base::OneShotTimer<TracingTimer> tracing_timer_;
     StartedFinalizingCallback callback_;
   };
 
+  typedef std::set<scoped_refptr<TraceMessageFilter>> FilterSet;
+  FilterSet filters_;

[oystein (OOO til 10th of July), 2015/07/21 20:52:45]

Could we just use the list in TraceControllerImpl, instead of tracking this
separately?

[shatch, 2015/07/22 17:44:13]

Thought about this a bit more, didn't get any great ideas on a cleaner way. To
reuse the list in TraceControllerImpl, we need to expose both a GetFilters()
method as well as some way to get notified when a filter is added so that we can
send the appropriate IPC's to setup callbacks. Put up a version that does that,
tell me what you think.

+
   scoped_ptr<TracingDelegate> delegate_;
   scoped_ptr<content::BackgroundTracingConfig> config_;
   std::map<TriggerHandle, std::string> trigger_handles_;
   scoped_ptr<TracingTimer> tracing_timer_;
   ReceiveCallback receive_callback_;
 
   bool is_gathering_;
   bool is_tracing_;
   bool requires_anonymized_data_;
   int trigger_handle_ids_;
 
   IdleCallback idle_callback_;
   base::Closure tracing_enabled_callback_for_testing_;
 
   friend struct base::DefaultLazyInstanceTraits<BackgroundTracingManagerImpl>;
 
   DISALLOW_COPY_AND_ASSIGN(BackgroundTracingManagerImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_TRACING_BACKGROUND_TRACING_MANAGER_IMPL_H_