1 /* 2 * Copyright (C) 2019 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef _UI_INPUT_STATISTICS_H 18 #define _UI_INPUT_STATISTICS_H 19 20 #include <android-base/chrono_utils.h> 21 22 #include <stddef.h> 23 24 namespace android { 25 26 class LatencyStatistics { 27 private: 28 /* Minimum sample recorded */ 29 float mMin; 30 /* Maximum sample recorded */ 31 float mMax; 32 /* Sum of all samples recorded */ 33 float mSum; 34 /* Sum of all the squares of samples recorded */ 35 float mSum2; 36 /* Count of all samples recorded */ 37 size_t mCount; 38 /* The last time statistics were reported */ 39 std::chrono::steady_clock::time_point mLastReportTime; 40 /* Statistics Report Frequency */ 41 const std::chrono::seconds mReportPeriod; 42 43 public: 44 LatencyStatistics(std::chrono::seconds period); 45 46 void addValue(float); 47 void reset(); 48 bool shouldReport(); 49 50 float getMean(); 51 float getMin(); 52 float getMax(); 53 float getStDev(); 54 size_t getCount(); 55 }; 56 57 } // namespace android 58 59 #endif // _UI_INPUT_STATISTICS_H 60