1 // Copyright (c) 2012 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 // This is a glue file, which allows third party code to call into our profiler 6 // without having to include most any functions from base. 7 8 #ifndef BASE_PROFILER_ALTERNATE_TIMER_H_ 9 #define BASE_PROFILER_ALTERNATE_TIMER_H_ 10 11 #include "base/base_export.h" 12 13 namespace tracked_objects { 14 15 enum TimeSourceType { 16 TIME_SOURCE_TYPE_WALL_TIME, 17 TIME_SOURCE_TYPE_TCMALLOC 18 }; 19 20 // Provide type for an alternate timer function. 21 typedef unsigned int NowFunction(); 22 23 // Environment variable name that is used to activate alternate timer profiling 24 // (such as using TCMalloc allocations to provide a pseudo-timer) for tasks 25 // instead of wall clock profiling. 26 BASE_EXPORT extern const char kAlternateProfilerTime[]; 27 28 // Set an alternate timer function to replace the OS time function when 29 // profiling. Typically this is called by an allocator that is providing a 30 // function that indicates how much memory has been allocated on any given 31 // thread. 32 BASE_EXPORT void SetAlternateTimeSource(NowFunction* now_function, 33 TimeSourceType type); 34 35 // Gets the pointer to a function that was set via SetAlternateTimeSource(). 36 // Returns NULL if no set was done prior to calling GetAlternateTimeSource. 37 NowFunction* GetAlternateTimeSource(); 38 39 // Returns the type of the currently set time source. 40 BASE_EXPORT TimeSourceType GetTimeSourceType(); 41 42 } // namespace tracked_objects 43 44 #endif // BASE_PROFILER_ALTERNATE_TIMER_H_ 45