Howard Hao | 1f81981 | 2021-06-21 15:28:29 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2021 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 | package com.android.car.telemetry.systemmonitor; |
| 18 | |
Howard Hao | 2b11eb5 | 2021-08-06 16:43:24 -0700 | [diff] [blame^] | 19 | import android.annotation.Nullable; |
| 20 | import android.app.ActivityManager; |
| 21 | import android.app.ActivityManager.MemoryInfo; |
| 22 | import android.content.Context; |
| 23 | import android.os.Handler; |
| 24 | import android.util.Slog; |
| 25 | |
| 26 | import com.android.car.CarLog; |
| 27 | import com.android.internal.annotations.GuardedBy; |
| 28 | import com.android.internal.annotations.VisibleForTesting; |
| 29 | |
| 30 | import java.io.BufferedReader; |
| 31 | import java.io.FileReader; |
| 32 | import java.io.IOException; |
| 33 | |
Howard Hao | 1f81981 | 2021-06-21 15:28:29 -0700 | [diff] [blame] | 34 | /** |
| 35 | * SystemMonitor monitors system states and report to listeners when there are |
| 36 | * important changes. |
| 37 | */ |
| 38 | public class SystemMonitor { |
| 39 | |
Howard Hao | 2b11eb5 | 2021-08-06 16:43:24 -0700 | [diff] [blame^] | 40 | private static final int NUM_LOADAVG_VALS = 3; |
| 41 | private static final float HI_CPU_LOAD_PER_CORE_BASE_LEVEL = 1.0f; |
| 42 | private static final float MED_CPU_LOAD_PER_CORE_BASE_LEVEL = 0.5f; |
| 43 | private static final float HI_MEM_LOAD_BASE_LEVEL = 0.95f; |
| 44 | private static final float MED_MEM_LOAD_BASE_LEVEL = 0.80f; |
| 45 | private static final String LOADAVG_PATH = "/proc/loadavg"; |
| 46 | |
| 47 | private static final int POLL_INTERVAL_MILLIS = 60000; |
| 48 | |
| 49 | private final Handler mWorkerHandler; |
| 50 | |
| 51 | private final Object mLock = new Object(); |
| 52 | |
| 53 | private final Context mContext; |
| 54 | private final ActivityManager mActivityManager; |
| 55 | private final String mLoadavgPath; |
| 56 | |
| 57 | @GuardedBy("mLock") |
| 58 | @Nullable private SystemMonitorCallback mCallback; |
| 59 | @GuardedBy("mLock") |
| 60 | private boolean mSystemMonitorRunning = false; |
| 61 | |
Howard Hao | 1f81981 | 2021-06-21 15:28:29 -0700 | [diff] [blame] | 62 | |
| 63 | /** |
| 64 | * Interface for receiving notifications about system monitor changes. |
| 65 | */ |
| 66 | public interface SystemMonitorCallback { |
| 67 | /** |
| 68 | * Listens to system monitor event. |
| 69 | * |
| 70 | * @param event the system monitor event. |
| 71 | */ |
| 72 | void onSystemMonitorEvent(SystemMonitorEvent event); |
| 73 | } |
| 74 | |
| 75 | /** |
Howard Hao | 2b11eb5 | 2021-08-06 16:43:24 -0700 | [diff] [blame^] | 76 | * Creates a SystemMonitor instance set with default loadavg path. |
| 77 | * |
| 78 | * @param context the context this is running in. |
| 79 | * @param workerHandler a handler for running monitoring jobs. |
| 80 | * @return SystemMonitor instance. |
| 81 | */ |
| 82 | public static SystemMonitor create(Context context, Handler workerHandler) { |
| 83 | return new SystemMonitor(context, workerHandler, LOADAVG_PATH); |
| 84 | } |
| 85 | |
| 86 | @VisibleForTesting |
| 87 | SystemMonitor(Context context, Handler workerHandler, String loadavgPath) { |
| 88 | mContext = context; |
| 89 | mWorkerHandler = workerHandler; |
| 90 | mActivityManager = (ActivityManager) |
| 91 | mContext.getSystemService(Context.ACTIVITY_SERVICE); |
| 92 | mLoadavgPath = loadavgPath; |
| 93 | } |
| 94 | |
| 95 | /** |
| 96 | * Sets the {@link SystemMonitorCallback} to notify of system state changes. |
Howard Hao | 1f81981 | 2021-06-21 15:28:29 -0700 | [diff] [blame] | 97 | * |
| 98 | * @param callback the callback to nofify state changes on. |
| 99 | */ |
| 100 | public void setSystemMonitorCallback(SystemMonitorCallback callback) { |
Howard Hao | 2b11eb5 | 2021-08-06 16:43:24 -0700 | [diff] [blame^] | 101 | synchronized (mLock) { |
| 102 | mCallback = callback; |
| 103 | if (!mWorkerHandler.hasCallbacks(this::getSystemLoadRepeated)) { |
| 104 | startSystemLoadMonitoring(); |
| 105 | } |
| 106 | } |
| 107 | } |
| 108 | |
| 109 | /** |
| 110 | * Unsets the {@link SystemMonitorCallback}. |
| 111 | */ |
| 112 | public void unsetSystemMonitorCallback() { |
| 113 | synchronized (mLock) { |
| 114 | stopSystemLoadMonitoringLocked(); |
| 115 | mCallback = null; |
| 116 | } |
| 117 | } |
| 118 | |
| 119 | /** |
| 120 | * Gets the loadavg data from /proc/loadavg, getting the first 3 averages, |
| 121 | * which are 1-min, 5-min and 15-min moving averages respectively. |
| 122 | * |
| 123 | * Requires Selinux permissions 'open', 'read, 'getattr' to proc_loadavg, |
| 124 | * which is set in Car/car_product/sepolicy/private/carservice_app.te. |
| 125 | * |
| 126 | * @return the {@link CpuLoadavg}. |
| 127 | */ |
| 128 | @VisibleForTesting |
| 129 | @Nullable |
| 130 | CpuLoadavg getCpuLoad() { |
| 131 | try (BufferedReader reader = new BufferedReader(new FileReader(mLoadavgPath))) { |
| 132 | String line = reader.readLine(); |
| 133 | String[] vals = line.split("\\s+", NUM_LOADAVG_VALS + 1); |
| 134 | if (vals.length < NUM_LOADAVG_VALS) { |
| 135 | Slog.w(CarLog.TAG_TELEMETRY, "Loadavg wrong format"); |
| 136 | return null; |
| 137 | } |
| 138 | CpuLoadavg cpuLoadavg = new CpuLoadavg(); |
| 139 | cpuLoadavg.mOneMinuteVal = Float.parseFloat(vals[0]); |
| 140 | cpuLoadavg.mFiveMinutesVal = Float.parseFloat(vals[1]); |
| 141 | cpuLoadavg.mFifteenMinutesVal = Float.parseFloat(vals[2]); |
| 142 | return cpuLoadavg; |
| 143 | } catch (IOException | NumberFormatException ex) { |
| 144 | Slog.w(CarLog.TAG_TELEMETRY, "Failed to read loadavg file.", ex); |
| 145 | return null; |
| 146 | } |
| 147 | } |
| 148 | |
| 149 | /** |
| 150 | * Gets the {@link ActivityManager.MemoryInfo} for system memory pressure. |
| 151 | * |
| 152 | * Of the MemoryInfo fields, we will only be using availMem and totalMem, |
| 153 | * since lowMemory and threshold are likely deprecated. |
| 154 | * |
| 155 | * @return {@link MemoryInfo} for the system. |
| 156 | */ |
| 157 | private MemoryInfo getMemoryLoad() { |
| 158 | MemoryInfo mi = new ActivityManager.MemoryInfo(); |
| 159 | mActivityManager.getMemoryInfo(mi); |
| 160 | return mi; |
| 161 | } |
| 162 | |
| 163 | /** |
| 164 | * Sets the CPU usage level for a {@link SystemMonitorEvent}. |
| 165 | * |
| 166 | * @param event the {@link SystemMonitorEvent}. |
| 167 | * @param cpuLoadPerCore the CPU load average per CPU core. |
| 168 | */ |
| 169 | @VisibleForTesting |
| 170 | void setEventCpuUsageLevel(SystemMonitorEvent event, double cpuLoadPerCore) { |
| 171 | if (cpuLoadPerCore > HI_CPU_LOAD_PER_CORE_BASE_LEVEL) { |
| 172 | event.setCpuUsageLevel(SystemMonitorEvent.USAGE_LEVEL_HI); |
| 173 | } else if (cpuLoadPerCore > MED_CPU_LOAD_PER_CORE_BASE_LEVEL |
| 174 | && cpuLoadPerCore <= HI_CPU_LOAD_PER_CORE_BASE_LEVEL) { |
| 175 | event.setCpuUsageLevel(SystemMonitorEvent.USAGE_LEVEL_MED); |
| 176 | } else { |
| 177 | event.setCpuUsageLevel(SystemMonitorEvent.USAGE_LEVEL_LOW); |
| 178 | } |
| 179 | } |
| 180 | |
| 181 | /** |
| 182 | * Sets the memory usage level for a {@link SystemMonitorEvent}. |
| 183 | * |
| 184 | * @param event the {@link SystemMonitorEvent}. |
| 185 | * @param memLoadRatio ratio of used memory to total memory. |
| 186 | */ |
| 187 | @VisibleForTesting |
| 188 | void setEventMemUsageLevel(SystemMonitorEvent event, double memLoadRatio) { |
| 189 | if (memLoadRatio > HI_MEM_LOAD_BASE_LEVEL) { |
| 190 | event.setMemoryUsageLevel(SystemMonitorEvent.USAGE_LEVEL_HI); |
| 191 | } else if (memLoadRatio > MED_MEM_LOAD_BASE_LEVEL |
| 192 | && memLoadRatio <= HI_MEM_LOAD_BASE_LEVEL) { |
| 193 | event.setMemoryUsageLevel(SystemMonitorEvent.USAGE_LEVEL_MED); |
| 194 | } else { |
| 195 | event.setMemoryUsageLevel(SystemMonitorEvent.USAGE_LEVEL_LOW); |
| 196 | } |
| 197 | } |
| 198 | |
| 199 | /** |
| 200 | * The Runnable to repeatedly getting system load data with some interval. |
| 201 | */ |
| 202 | private void getSystemLoadRepeated() { |
| 203 | synchronized (mLock) { |
| 204 | try { |
| 205 | CpuLoadavg cpuLoadAvg = getCpuLoad(); |
| 206 | if (cpuLoadAvg == null) { |
| 207 | return; |
| 208 | } |
| 209 | int numProcessors = Runtime.getRuntime().availableProcessors(); |
| 210 | |
| 211 | MemoryInfo memInfo = getMemoryLoad(); |
| 212 | |
| 213 | SystemMonitorEvent event = new SystemMonitorEvent(); |
| 214 | setEventCpuUsageLevel(event, cpuLoadAvg.mOneMinuteVal / numProcessors); |
| 215 | setEventMemUsageLevel(event, 1 - memInfo.availMem / memInfo.totalMem); |
| 216 | |
| 217 | mCallback.onSystemMonitorEvent(event); |
| 218 | } finally { |
| 219 | if (mSystemMonitorRunning) { |
| 220 | mWorkerHandler.postDelayed(this::getSystemLoadRepeated, POLL_INTERVAL_MILLIS); |
| 221 | } |
| 222 | } |
| 223 | } |
| 224 | } |
| 225 | |
| 226 | /** |
| 227 | * Starts system load monitoring. |
| 228 | */ |
| 229 | private void startSystemLoadMonitoring() { |
| 230 | synchronized (mLock) { |
| 231 | mWorkerHandler.post(this::getSystemLoadRepeated); |
| 232 | mSystemMonitorRunning = true; |
| 233 | } |
| 234 | } |
| 235 | |
| 236 | /** |
| 237 | * Stops system load monitoring. |
| 238 | */ |
| 239 | @GuardedBy("mLock") |
| 240 | private void stopSystemLoadMonitoringLocked() { |
| 241 | synchronized (mLock) { |
| 242 | mWorkerHandler.removeCallbacks(this::getSystemLoadRepeated); |
| 243 | mSystemMonitorRunning = false; |
| 244 | } |
| 245 | } |
| 246 | |
| 247 | static final class CpuLoadavg { |
| 248 | float mOneMinuteVal; |
| 249 | float mFiveMinutesVal; |
| 250 | float mFifteenMinutesVal; |
Howard Hao | 1f81981 | 2021-06-21 15:28:29 -0700 | [diff] [blame] | 251 | } |
| 252 | } |