1 /* 2 ** 3 ** Copyright 2015, The Android Open Source Project 4 ** 5 ** Licensed under the Apache License, Version 2.0 (the "License"); 6 ** you may not use this file except in compliance with the License. 7 ** You may obtain a copy of the License at 8 ** 9 ** http://www.apache.org/licenses/LICENSE-2.0 10 ** 11 ** Unless required by applicable law or agreed to in writing, software 12 ** distributed under the License is distributed on an "AS IS" BASIS, 13 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 ** See the License for the specific language governing permissions and 15 ** limitations under the License. 16 */ 17 18 // 19 // Helper class to perform cpu setup (if needed) prior to a profile collection. 20 // 21 class HardwireCpuHelper { 22 public: 23 24 // The constructor for this class checks to see if the 'mpdecision' 25 // service is running; if so (and if 'perform' is TRUE), then it 26 // disables the service and on-lines all of the available cores/cpus 27 // (anything listed in /sys/devices/system/cpu/possible). The 28 // destructor will re-enable the mpdecision service if it was 29 // previously disabled. 30 HardwireCpuHelper(bool perform); 31 virtual ~HardwireCpuHelper(); 32 33 private: 34 bool mpdecision_stopped_; 35 36 // Collect the number of available cpus/cores from /sys/devices/system/cpu/possible 37 int GetNumCores(); 38 39 // Returns TRUE if the system service 'mpdecision' is running 40 bool GetMpdecisionRunning(); 41 42 // Online/offline the specified cpu 43 void OnlineCore(int whichCore, int onoff); 44 45 // Enable/disable the mpdecision service via the equivalent of 46 // setprop ctl.start mpdecision 47 // setprop ctl.stop mpdecision 48 void StopMpdecision(); 49 void RestartMpdecision(); 50 }; 51