| /* |
| * Copyright (C) 2015 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package com.android.internal.os; |
| |
| import android.annotation.Nullable; |
| import android.os.SystemClock; |
| import android.text.TextUtils; |
| import android.util.Slog; |
| import android.util.SparseLongArray; |
| import android.util.TimeUtils; |
| |
| import java.io.BufferedReader; |
| import java.io.FileReader; |
| import java.io.FileWriter; |
| import java.io.IOException; |
| |
| /** |
| * Reads /proc/uid_cputime/show_uid_stat which has the line format: |
| * |
| * uid: user_time_micro_seconds system_time_micro_seconds power_in_milli-amp-micro_seconds |
| * |
| * This provides the time a UID's processes spent executing in user-space and kernel-space. |
| * The file contains a monotonically increasing count of time for a single boot. This class |
| * maintains the previous results of a call to {@link #readDelta} in order to provide a proper |
| * delta. |
| */ |
| public class KernelUidCpuTimeReader { |
| private static final String TAG = "KernelUidCpuTimeReader"; |
| private static final String sProcFile = "/proc/uid_cputime/show_uid_stat"; |
| private static final String sRemoveUidProcFile = "/proc/uid_cputime/remove_uid_range"; |
| |
| /** |
| * Callback interface for processing each line of the proc file. |
| */ |
| public interface Callback { |
| /** |
| * @param uid UID of the app |
| * @param userTimeUs time spent executing in user space in microseconds |
| * @param systemTimeUs time spent executing in kernel space in microseconds |
| * @param powerMaUs power consumed executing, in milli-ampere microseconds |
| */ |
| void onUidCpuTime(int uid, long userTimeUs, long systemTimeUs, long powerMaUs); |
| } |
| |
| private SparseLongArray mLastUserTimeUs = new SparseLongArray(); |
| private SparseLongArray mLastSystemTimeUs = new SparseLongArray(); |
| private SparseLongArray mLastPowerMaUs = new SparseLongArray(); |
| private long mLastTimeReadUs = 0; |
| |
| /** |
| * Reads the proc file, calling into the callback with a delta of time for each UID. |
| * @param callback The callback to invoke for each line of the proc file. If null, |
| * the data is consumed and subsequent calls to readDelta will provide |
| * a fresh delta. |
| */ |
| public void readDelta(@Nullable Callback callback) { |
| long nowUs = SystemClock.elapsedRealtime() * 1000; |
| try (BufferedReader reader = new BufferedReader(new FileReader(sProcFile))) { |
| TextUtils.SimpleStringSplitter splitter = new TextUtils.SimpleStringSplitter(' '); |
| String line; |
| while ((line = reader.readLine()) != null) { |
| splitter.setString(line); |
| final String uidStr = splitter.next(); |
| final int uid = Integer.parseInt(uidStr.substring(0, uidStr.length() - 1), 10); |
| final long userTimeUs = Long.parseLong(splitter.next(), 10); |
| final long systemTimeUs = Long.parseLong(splitter.next(), 10); |
| final long powerMaUs; |
| if (splitter.hasNext()) { |
| powerMaUs = Long.parseLong(splitter.next(), 10) / 1000; |
| } else { |
| powerMaUs = 0; |
| } |
| |
| // Only report if there is a callback and if this is not the first read. |
| if (callback != null && mLastTimeReadUs != 0) { |
| long userTimeDeltaUs = userTimeUs; |
| long systemTimeDeltaUs = systemTimeUs; |
| long powerDeltaMaUs = powerMaUs; |
| int index = mLastUserTimeUs.indexOfKey(uid); |
| if (index >= 0) { |
| userTimeDeltaUs -= mLastUserTimeUs.valueAt(index); |
| systemTimeDeltaUs -= mLastSystemTimeUs.valueAt(index); |
| powerDeltaMaUs -= mLastPowerMaUs.valueAt(index); |
| |
| final long timeDiffUs = nowUs - mLastTimeReadUs; |
| if (userTimeDeltaUs < 0 || systemTimeDeltaUs < 0 || powerDeltaMaUs < 0) { |
| StringBuilder sb = new StringBuilder("Malformed cpu data for UID="); |
| sb.append(uid).append("!\n"); |
| sb.append("Time between reads: "); |
| TimeUtils.formatDuration(timeDiffUs / 1000, sb); |
| sb.append("\n"); |
| sb.append("Previous times: u="); |
| TimeUtils.formatDuration(mLastUserTimeUs.valueAt(index) / 1000, sb); |
| sb.append(" s="); |
| TimeUtils.formatDuration(mLastSystemTimeUs.valueAt(index) / 1000, sb); |
| sb.append(" p=").append(mLastPowerMaUs.valueAt(index) / 1000); |
| sb.append("mAms\n"); |
| |
| sb.append("Current times: u="); |
| TimeUtils.formatDuration(userTimeUs / 1000, sb); |
| sb.append(" s="); |
| TimeUtils.formatDuration(systemTimeUs / 1000, sb); |
| sb.append(" p=").append(powerMaUs / 1000); |
| sb.append("mAms\n"); |
| sb.append("Delta: u="); |
| TimeUtils.formatDuration(userTimeDeltaUs / 1000, sb); |
| sb.append(" s="); |
| TimeUtils.formatDuration(systemTimeDeltaUs / 1000, sb); |
| sb.append(" p=").append(powerDeltaMaUs / 1000).append("mAms"); |
| Slog.e(TAG, sb.toString()); |
| |
| userTimeDeltaUs = 0; |
| systemTimeDeltaUs = 0; |
| powerDeltaMaUs = 0; |
| } |
| } |
| |
| if (userTimeDeltaUs != 0 || systemTimeDeltaUs != 0 || powerDeltaMaUs != 0) { |
| callback.onUidCpuTime(uid, userTimeDeltaUs, systemTimeDeltaUs, |
| powerDeltaMaUs); |
| } |
| } |
| mLastUserTimeUs.put(uid, userTimeUs); |
| mLastSystemTimeUs.put(uid, systemTimeUs); |
| mLastPowerMaUs.put(uid, powerMaUs); |
| } |
| } catch (IOException e) { |
| Slog.e(TAG, "Failed to read uid_cputime: " + e.getMessage()); |
| } |
| mLastTimeReadUs = nowUs; |
| } |
| |
| /** |
| * Removes the UID from the kernel module and from internal accounting data. |
| * @param uid The UID to remove. |
| */ |
| public void removeUid(int uid) { |
| int index = mLastUserTimeUs.indexOfKey(uid); |
| if (index >= 0) { |
| mLastUserTimeUs.removeAt(index); |
| mLastSystemTimeUs.removeAt(index); |
| mLastPowerMaUs.removeAt(index); |
| } |
| |
| try (FileWriter writer = new FileWriter(sRemoveUidProcFile)) { |
| writer.write(Integer.toString(uid) + "-" + Integer.toString(uid)); |
| writer.flush(); |
| } catch (IOException e) { |
| Slog.e(TAG, "failed to remove uid from uid_cputime module", e); |
| } |
| } |
| } |