base/profiler/scoped_profile.h

   1 // Copyright (c) 2011 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
   6 #ifndef BASE_PROFILER_SCOPED_PROFILE_H_
   7 #define BASE_PROFILER_SCOPED_PROFILE_H_
   8
   9 //------------------------------------------------------------------------------
  10 // ScopedProfile provides basic helper functions for profiling a short
  11 // region of code within a scope.  It is separate from the related ThreadData
  12 // class so that it can be included without much other cruft, and provide the
  13 // macros listed below.
  14
  15 #include "base/base_export.h"
  16 #include "base/location.h"
  17 #include "base/profiler/tracked_time.h"
  18
  19 #if defined(GOOGLE_CHROME_BUILD)
  20
  21 // We don't ship these profiled regions.  This is for developer builds only.
  22 // It allows developers to do some profiling of their code, and see results on
  23 // their about:profiler page.
  24 #define TRACK_RUN_IN_THIS_SCOPED_REGION_FOR_DEVELOPER_BUILDS(scope_name)       \
  25     ((void)0)
  26
  27 #else
  28
  29 #define TRACK_RUN_IN_THIS_SCOPED_REGION_FOR_DEVELOPER_BUILDS(scope_name)       \
  30     ::tracked_objects::ScopedProfile  LINE_BASED_VARIABLE_NAME_FOR_PROFILING(  \
  31         FROM_HERE_WITH_EXPLICIT_FUNCTION(#scope_name))
  32
  33 #endif
  34
  35
  36
  37 #define PASTE_LINE_NUMBER_ON_NAME(name, line) name##line
  38
  39 #define LINE_BASED_VARIABLE_NAME_FOR_PROFILING                                 \
  40     PASTE_LINE_NUMBER_ON_NAME(some_profiler_variable_, __LINE__)
  41
  42 #define TRACK_RUN_IN_IPC_HANDLER(dispatch_function_name)                       \
  43     ::tracked_objects::ScopedProfile some_tracking_variable_name(              \
  44         FROM_HERE_WITH_EXPLICIT_FUNCTION(#dispatch_function_name))
  45
  46
  47 namespace tracked_objects {
  48 class Births;
  49
  50 class BASE_EXPORT ScopedProfile {
  51  public:
  52   explicit ScopedProfile(const Location& location);
  53   ~ScopedProfile();
  54
  55   // Stop tracing prior to the end destruction of the instance.
  56   void StopClockAndTally();
  57
  58  private:
  59   Births* birth_;  // Place in code where tracking started.
  60   const TrackedTime start_of_run_;
  61
  62   DISALLOW_COPY_AND_ASSIGN(ScopedProfile);
  63 };
  64
  65 }  // namespace tracked_objects
  66
  67 #endif   // BASE_PROFILER_SCOPED_PROFILE_H_