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 CC_DEBUG_LAP_TIMER_H_ 6 #define CC_DEBUG_LAP_TIMER_H_ 7 8 #include "base/time/time.h" 9 #include "cc/base/cc_export.h" 10 11 namespace cc { 12 13 // LapTimer is used to calculate average times per "Lap" in perf tests. 14 // Current() reports the time since the last call to Start(). 15 // Store() adds the time since the last call to Start() to the accumulator, and 16 // resets the start time to now. Stored() returns the accumulated time. 17 // NextLap increments the lap counter, used in counting the per lap averages. 18 // If you initialize the LapTimer with a non zero warmup_laps, it will ignore 19 // the times for that many laps at the start. 20 // If you set the time_limit then you can use HasTimeLimitExpired() to see if 21 // the current accumulated time has crossed that threshold, with an optimization 22 // that it only tests this every check_interval laps. 23 class CC_EXPORT LapTimer { 24 public: 25 LapTimer(int warmup_laps, base::TimeDelta time_limit, int check_interval); 26 // Resets the timer back to it's starting state. 27 void Reset(); 28 // Sets the start point to now. 29 void Start(); 30 // Returns true if there are no more warmup laps to do. 31 bool IsWarmedUp(); 32 // Advance the lap counter and update the accumulated time. 33 // The accumulated time is only updated every check_interval laps. 34 // If accumulating then the start point will also be updated. 35 void NextLap(); 36 // Returns true if the stored time has exceeded the time limit specified. 37 // May cause a call to Store(). 38 bool HasTimeLimitExpired(); 39 // Returns true if all lap times have been timed. Only true every n'th 40 // lap, where n = check_interval. 41 bool HasTimedAllLaps(); 42 // The average milliseconds per lap. 43 float MsPerLap(); 44 // The number of laps per second. 45 float LapsPerSecond(); 46 // The number of laps recorded. 47 int NumLaps(); 48 49 private: 50 base::TimeTicks start_time_; 51 base::TimeDelta accumulator_; 52 int num_laps_; 53 int warmup_laps_; 54 int remaining_warmups_; 55 int remaining_no_check_laps_; 56 base::TimeDelta time_limit_; 57 int check_interval_; 58 59 DISALLOW_COPY_AND_ASSIGN(LapTimer); 60 }; 61 62 } // namespace cc 63 64 #endif // CC_DEBUG_LAP_TIMER_H_ 65
