content/browser/tracing/etw_system_event_consumer_win.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CONTENT_BROWSER_TRACING_ETW_SYSTEM_EVENT_CONSUMER_WIN_H_
   6 #define CONTENT_BROWSER_TRACING_ETW_SYSTEM_EVENT_CONSUMER_WIN_H_
   7
   8 #include "base/bind.h"
   9 #include "base/memory/ref_counted_memory.h"
  10 #include "base/threading/thread.h"
  11 #include "base/values.h"
  12 #include "base/win/event_trace_consumer.h"
  13 #include "base/win/event_trace_controller.h"
  14
  15 namespace base {
  16 template <typename Type>
  17 struct DefaultSingletonTraits;
  18 }
  19
  20 namespace content {
  21
  22 class EtwSystemEventConsumer :
  23     public base::win::EtwTraceConsumerBase<EtwSystemEventConsumer> {
  24  public:
  25   typedef base::Callback<void(const scoped_refptr<base::RefCountedString>&)>
  26       OutputCallback;
  27
  28   bool StartSystemTracing();
  29   void StopSystemTracing(const OutputCallback& callback);
  30
  31   // Retrieve the ETW consumer instance.
  32   static EtwSystemEventConsumer* GetInstance();
  33
  34  private:
  35   // This allows constructor and destructor to be private and usable only
  36   // by the Singleton class.
  37   friend struct base::DefaultSingletonTraits<EtwSystemEventConsumer>;
  38
  39   // Constructor.
  40   EtwSystemEventConsumer();
  41   virtual ~EtwSystemEventConsumer();
  42
  43   void AddSyncEventToBuffer();
  44   void AppendEventToBuffer(EVENT_TRACE* event);
  45
  46   // Static override of EtwTraceConsumerBase::ProcessEvent.
  47   // @param event the raw ETW event to process.
  48   friend class base::win::EtwTraceConsumerBase<EtwSystemEventConsumer>;
  49   static void ProcessEvent(EVENT_TRACE* event);
  50
  51   // Request the ETW trace controller to activate the kernel tracing.
  52   // returns true on success, false if the kernel tracing isn't activated.
  53   bool StartKernelSessionTracing();
  54
  55   // Request the ETW trace controller to deactivate the kernel tracing.
  56   // @param callback the callback to call with the consumed events.
  57   // @returns true on success, false if an error occurred.
  58   bool StopKernelSessionTracing();
  59
  60   void OnStopSystemTracingDone(
  61     const OutputCallback& callback,
  62     const scoped_refptr<base::RefCountedString>& result);
  63
  64   void TraceAndConsumeOnThread();
  65   void FlushOnThread(const OutputCallback& callback);
  66
  67   scoped_ptr<base::ListValue> events_;
  68   base::Thread thread_;
  69   TRACEHANDLE session_handle_;
  70   base::win::EtwTraceProperties properties_;
  71
  72   DISALLOW_COPY_AND_ASSIGN(EtwSystemEventConsumer);
  73 };
  74
  75 }  // namespace content
  76
  77 #endif  // CONTENT_BROWSER_TRACING_ETW_SYSTEM_EVENT_CONSUMER_WIN_H_