content/public/browser/tracing_controller.h

   1 // Copyright 2013 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_PUBLIC_BROWSER_TRACING_CONTROLLER_H_
   6 #define CONTENT_PUBLIC_BROWSER_TRACING_CONTROLLER_H_
   7
   8 #include <set>
   9 #include <string>
  10
  11 #include "base/callback.h"
  12 #include "base/memory/ref_counted.h"
  13 #include "base/trace_event/trace_event.h"
  14 #include "content/common/content_export.h"
  15
  16 namespace content {
  17
  18 class TracingController;
  19
  20 // TracingController is used on the browser processes to enable/disable
  21 // trace status and collect trace data. Only the browser UI thread is allowed
  22 // to interact with the TracingController object. All callbacks are called on
  23 // the UI thread.
  24 class TracingController {
  25  public:
  26
  27   CONTENT_EXPORT static TracingController* GetInstance();
  28
  29   // An interface for trace data consumer. An implemnentation of this interface
  30   // is passed to either DisableTracing() or CaptureMonitoringSnapshot() and
  31   // receives the trace data followed by a notification that all child processes
  32   // have completed tracing and the data collection is over.
  33   // All methods are called on the UI thread.
  34   // Close method will be called exactly once and no methods will be
  35   // called after that.
  36   class CONTENT_EXPORT TraceDataSink
  37       : public base::RefCountedThreadSafe<TraceDataSink> {
  38    public:
  39     virtual void AddTraceChunk(const std::string& chunk) {}
  40     virtual void SetSystemTrace(const std::string& data) {}
  41     virtual void SetMetadata(const std::string& data) {}
  42     virtual void Close() {}
  43
  44    protected:
  45     friend class base::RefCountedThreadSafe<TraceDataSink>;
  46     virtual ~TraceDataSink() {}
  47   };
  48
  49   // An implementation of this interface is passed when constructing a
  50   // TraceDataSink, and receives chunks of the final trace data as it's being
  51   // constructed.
  52   // Methods may be called from any thread.
  53   class CONTENT_EXPORT TraceDataEndpoint
  54       : public base::RefCountedThreadSafe<TraceDataEndpoint> {
  55    public:
  56     virtual void ReceiveTraceChunk(const std::string& chunk) {}
  57     virtual void ReceiveTraceFinalContents(const std::string& contents) {}
  58
  59    protected:
  60     friend class base::RefCountedThreadSafe<TraceDataEndpoint>;
  61     virtual ~TraceDataEndpoint() {}
  62   };
  63
  64   // Create a trace sink that may be supplied to DisableRecording or
  65   // CaptureMonitoringSnapshot to capture the trace data as a string.
  66   CONTENT_EXPORT static scoped_refptr<TraceDataSink> CreateStringSink(
  67       const base::Callback<void(base::RefCountedString*)>& callback);
  68
  69   CONTENT_EXPORT static scoped_refptr<TraceDataSink> CreateCompressedStringSink(
  70       scoped_refptr<TraceDataEndpoint> endpoint);
  71
  72   // Create a trace sink that may be supplied to DisableRecording or
  73   // CaptureMonitoringSnapshot to dump the trace data to a file.
  74   CONTENT_EXPORT static scoped_refptr<TraceDataSink> CreateFileSink(
  75       const base::FilePath& file_path,
  76       const base::Closure& callback);
  77
  78   // Create an endpoint that may be supplied to any TraceDataSink to
  79   // dump the trace data to a file.
  80   CONTENT_EXPORT static scoped_refptr<TraceDataEndpoint> CreateFileEndpoint(
  81       const base::FilePath& file_path,
  82       const base::Closure& callback);
  83
  84   // Get a set of category groups. The category groups can change as
  85   // new code paths are reached.
  86   //
  87   // Once all child processes have acked to the GetCategories request,
  88   // GetCategoriesDoneCallback is called back with a set of category
  89   // groups.
  90   typedef base::Callback<void(const std::set<std::string>&)>
  91       GetCategoriesDoneCallback;
  92   virtual bool GetCategories(
  93       const GetCategoriesDoneCallback& callback) = 0;
  94
  95   // Start recording on all processes.
  96   //
  97   // Recording begins immediately locally, and asynchronously on child processes
  98   // as soon as they receive the EnableRecording request.
  99   //
 100   // Once all child processes have acked to the EnableRecording request,
 101   // EnableRecordingDoneCallback will be called back.
 102   //
 103   // |category_filter| is a filter to control what category groups should be
 104   // traced. A filter can have an optional '-' prefix to exclude category groups
 105   // that contain a matching category. Having both included and excluded
 106   // category patterns in the same list would not be supported.
 107   //
 108   // Examples: "test_MyTest*",
 109   //           "test_MyTest*,test_OtherStuff",
 110   //           "-excluded_category1,-excluded_category2"
 111   //
 112   // |options| controls what kind of tracing is enabled.
 113   typedef base::Callback<void()> EnableRecordingDoneCallback;
 114   virtual bool EnableRecording(
 115       const base::trace_event::TraceConfig& trace_config,
 116       const EnableRecordingDoneCallback& callback) = 0;
 117
 118   // Stop recording on all processes.
 119   //
 120   // Child processes typically are caching trace data and only rarely flush
 121   // and send trace data back to the browser process. That is because it may be
 122   // an expensive operation to send the trace data over IPC, and we would like
 123   // to avoid much runtime overhead of tracing. So, to end tracing, we must
 124   // asynchronously ask all child processes to flush any pending trace data.
 125   //
 126   // Once all child processes have acked to the DisableRecording request,
 127   // TracingFileResultCallback will be called back with a file that contains
 128   // the traced data.
 129   //
 130   // If |trace_data_sink| is not null, it will receive chunks of trace data
 131   // as a comma-separated sequences of JSON-stringified events, followed by
 132   // a notification that the trace collection is finished.
 133   //
 134   virtual bool DisableRecording(
 135       const scoped_refptr<TraceDataSink>& trace_data_sink) = 0;
 136
 137   // Start monitoring on all processes.
 138   //
 139   // Monitoring begins immediately locally, and asynchronously on child
 140   // processes as soon as they receive the EnableMonitoring request.
 141   //
 142   // Once all child processes have acked to the EnableMonitoring request,
 143   // EnableMonitoringDoneCallback will be called back.
 144   //
 145   // |category_filter| is a filter to control what category groups should be
 146   // traced.
 147   //
 148   // |options| controls what kind of tracing is enabled.
 149   typedef base::Callback<void()> EnableMonitoringDoneCallback;
 150   virtual bool EnableMonitoring(
 151       const base::trace_event::TraceConfig& trace_config,
 152       const EnableMonitoringDoneCallback& callback) = 0;
 153
 154   // Stop monitoring on all processes.
 155   //
 156   // Once all child processes have acked to the DisableMonitoring request,
 157   // DisableMonitoringDoneCallback is called back.
 158   typedef base::Callback<void()> DisableMonitoringDoneCallback;
 159   virtual bool DisableMonitoring(
 160       const DisableMonitoringDoneCallback& callback) = 0;
 161
 162   // Get the current monitoring configuration.
 163   virtual void GetMonitoringStatus(
 164       bool* out_enabled,
 165       base::trace_event::TraceConfig* out_trace_config) = 0;
 166
 167   // Get the current monitoring traced data.
 168   //
 169   // Child processes typically are caching trace data and only rarely flush
 170   // and send trace data back to the browser process. That is because it may be
 171   // an expensive operation to send the trace data over IPC, and we would like
 172   // to avoid much runtime overhead of tracing. So, to end tracing, we must
 173   // asynchronously ask all child processes to flush any pending trace data.
 174   //
 175   // Once all child processes have acked to the CaptureMonitoringSnapshot
 176   // request, TracingFileResultCallback will be called back with a file that
 177   // contains the traced data.
 178   //
 179   // If |trace_data_sink| is not null, it will receive chunks of trace data
 180   // as a comma-separated sequences of JSON-stringified events, followed by
 181   // a notification that the trace collection is finished.
 182   virtual bool CaptureMonitoringSnapshot(
 183       const scoped_refptr<TraceDataSink>& trace_data_sink) = 0;
 184
 185   // Get the maximum across processes of trace buffer percent full state.
 186   // When the TraceBufferUsage value is determined, the callback is
 187   // called.
 188   typedef base::Callback<void(float, size_t)> GetTraceBufferUsageCallback;
 189   virtual bool GetTraceBufferUsage(
 190       const GetTraceBufferUsageCallback& callback) = 0;
 191
 192   // |callback| will will be called every time the given event occurs on any
 193   // process.
 194   typedef base::Callback<void()> WatchEventCallback;
 195   virtual bool SetWatchEvent(const std::string& category_name,
 196                              const std::string& event_name,
 197                              const WatchEventCallback& callback) = 0;
 198
 199   // Cancel the watch event. If tracing is enabled, this may race with the
 200   // watch event callback.
 201   virtual bool CancelWatchEvent() = 0;
 202
 203   // Check if the tracing system is recording
 204   virtual bool IsRecording() const = 0;
 205
 206  protected:
 207   virtual ~TracingController() {}
 208 };
 209
 210 }  // namespace content
 211
 212 #endif  // CONTENT_PUBLIC_BROWSER_TRACING_CONTROLLER_H_