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