| /* |
| * Copyright (C) 2017 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 static com.android.internal.util.Preconditions.checkNotNull; |
| |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.os.StrictMode; |
| import android.util.IntArray; |
| import android.util.Slog; |
| import android.util.SparseArray; |
| |
| import com.android.internal.annotations.VisibleForTesting; |
| |
| import java.io.BufferedReader; |
| import java.io.FileReader; |
| import java.io.IOException; |
| import java.nio.ByteBuffer; |
| import java.nio.IntBuffer; |
| import java.util.function.Consumer; |
| |
| /** |
| * Reads /proc/uid_time_in_state which has the format: |
| * |
| * uid: [freq1] [freq2] [freq3] ... |
| * [uid1]: [time in freq1] [time in freq2] [time in freq3] ... |
| * [uid2]: [time in freq1] [time in freq2] [time in freq3] ... |
| * ... |
| * |
| * Binary variation reads /proc/uid_cpupower/time_in_state in the following format: |
| * [n, uid0, time0a, time0b, ..., time0n, |
| * uid1, time1a, time1b, ..., time1n, |
| * uid2, time2a, time2b, ..., time2n, etc.] |
| * where n is the total number of frequencies. |
| * |
| * This provides the times a UID's processes spent executing at each different cpu frequency. |
| * 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. |
| * |
| * This class uses a throttler to reject any {@link #readDelta} call within |
| * {@link #mThrottleInterval}. This is different from the throttler in {@link KernelCpuProcReader}, |
| * which has a shorter throttle interval and returns cached result from last read when the request |
| * is throttled. |
| * |
| * This class is NOT thread-safe and NOT designed to be accessed by more than one caller since each |
| * caller has its own view of delta. |
| */ |
| public class KernelUidCpuFreqTimeReader extends |
| KernelUidCpuTimeReaderBase<KernelUidCpuFreqTimeReader.Callback> { |
| private static final String TAG = KernelUidCpuFreqTimeReader.class.getSimpleName(); |
| static final String UID_TIMES_PROC_FILE = "/proc/uid_time_in_state"; |
| |
| public interface Callback extends KernelUidCpuTimeReaderBase.Callback { |
| void onUidCpuFreqTime(int uid, long[] cpuFreqTimeMs); |
| } |
| |
| private long[] mCpuFreqs; |
| private long[] mCurTimes; // Reuse to prevent GC. |
| private long[] mDeltaTimes; // Reuse to prevent GC. |
| private int mCpuFreqsCount; |
| private final KernelCpuProcReader mProcReader; |
| |
| private SparseArray<long[]> mLastUidCpuFreqTimeMs = new SparseArray<>(); |
| |
| // We check the existence of proc file a few times (just in case it is not ready yet when we |
| // start reading) and if it is not available, we simply ignore further read requests. |
| private static final int TOTAL_READ_ERROR_COUNT = 5; |
| private int mReadErrorCounter; |
| private boolean mPerClusterTimesAvailable; |
| private boolean mAllUidTimesAvailable = true; |
| |
| public KernelUidCpuFreqTimeReader() { |
| mProcReader = KernelCpuProcReader.getFreqTimeReaderInstance(); |
| } |
| |
| @VisibleForTesting |
| public KernelUidCpuFreqTimeReader(KernelCpuProcReader procReader) { |
| mProcReader = procReader; |
| } |
| |
| public boolean perClusterTimesAvailable() { |
| return mPerClusterTimesAvailable; |
| } |
| |
| public boolean allUidTimesAvailable() { |
| return mAllUidTimesAvailable; |
| } |
| |
| public SparseArray<long[]> getAllUidCpuFreqTimeMs() { |
| return mLastUidCpuFreqTimeMs; |
| } |
| |
| public long[] readFreqs(@NonNull PowerProfile powerProfile) { |
| checkNotNull(powerProfile); |
| if (mCpuFreqs != null) { |
| // No need to read cpu freqs more than once. |
| return mCpuFreqs; |
| } |
| if (!mAllUidTimesAvailable) { |
| return null; |
| } |
| final int oldMask = StrictMode.allowThreadDiskReadsMask(); |
| try (BufferedReader reader = new BufferedReader(new FileReader(UID_TIMES_PROC_FILE))) { |
| return readFreqs(reader, powerProfile); |
| } catch (IOException e) { |
| if (++mReadErrorCounter >= TOTAL_READ_ERROR_COUNT) { |
| mAllUidTimesAvailable = false; |
| } |
| Slog.e(TAG, "Failed to read " + UID_TIMES_PROC_FILE + ": " + e); |
| return null; |
| } finally { |
| StrictMode.setThreadPolicyMask(oldMask); |
| } |
| } |
| |
| @VisibleForTesting |
| public long[] readFreqs(BufferedReader reader, PowerProfile powerProfile) |
| throws IOException { |
| final String line = reader.readLine(); |
| if (line == null) { |
| return null; |
| } |
| final String[] freqStr = line.split(" "); |
| // First item would be "uid: " which needs to be ignored. |
| mCpuFreqsCount = freqStr.length - 1; |
| mCpuFreqs = new long[mCpuFreqsCount]; |
| mCurTimes = new long[mCpuFreqsCount]; |
| mDeltaTimes = new long[mCpuFreqsCount]; |
| for (int i = 0; i < mCpuFreqsCount; ++i) { |
| mCpuFreqs[i] = Long.parseLong(freqStr[i + 1], 10); |
| } |
| |
| // Check if the freqs in the proc file correspond to per-cluster freqs. |
| final IntArray numClusterFreqs = extractClusterInfoFromProcFileFreqs(); |
| final int numClusters = powerProfile.getNumCpuClusters(); |
| if (numClusterFreqs.size() == numClusters) { |
| mPerClusterTimesAvailable = true; |
| for (int i = 0; i < numClusters; ++i) { |
| if (numClusterFreqs.get(i) != powerProfile.getNumSpeedStepsInCpuCluster(i)) { |
| mPerClusterTimesAvailable = false; |
| break; |
| } |
| } |
| } else { |
| mPerClusterTimesAvailable = false; |
| } |
| Slog.i(TAG, "mPerClusterTimesAvailable=" + mPerClusterTimesAvailable); |
| return mCpuFreqs; |
| } |
| |
| @Override |
| @VisibleForTesting |
| public void readDeltaImpl(@Nullable Callback callback) { |
| if (mCpuFreqs == null) { |
| return; |
| } |
| readImpl((buf) -> { |
| int uid = buf.get(); |
| long[] lastTimes = mLastUidCpuFreqTimeMs.get(uid); |
| if (lastTimes == null) { |
| lastTimes = new long[mCpuFreqsCount]; |
| mLastUidCpuFreqTimeMs.put(uid, lastTimes); |
| } |
| if (!getFreqTimeForUid(buf, mCurTimes)) { |
| return; |
| } |
| boolean notify = false; |
| boolean valid = true; |
| for (int i = 0; i < mCpuFreqsCount; i++) { |
| mDeltaTimes[i] = mCurTimes[i] - lastTimes[i]; |
| if (mDeltaTimes[i] < 0) { |
| Slog.e(TAG, "Negative delta from freq time proc: " + mDeltaTimes[i]); |
| valid = false; |
| } |
| notify |= mDeltaTimes[i] > 0; |
| } |
| if (notify && valid) { |
| System.arraycopy(mCurTimes, 0, lastTimes, 0, mCpuFreqsCount); |
| if (callback != null) { |
| callback.onUidCpuFreqTime(uid, mDeltaTimes); |
| } |
| } |
| }); |
| } |
| |
| public void readAbsolute(Callback callback) { |
| readImpl((buf) -> { |
| int uid = buf.get(); |
| if (getFreqTimeForUid(buf, mCurTimes)) { |
| callback.onUidCpuFreqTime(uid, mCurTimes); |
| } |
| }); |
| } |
| |
| private boolean getFreqTimeForUid(IntBuffer buffer, long[] freqTime) { |
| boolean valid = true; |
| for (int i = 0; i < mCpuFreqsCount; i++) { |
| freqTime[i] = (long) buffer.get() * 10; // Unit is 10ms. |
| if (freqTime[i] < 0) { |
| Slog.e(TAG, "Negative time from freq time proc: " + freqTime[i]); |
| valid = false; |
| } |
| } |
| return valid; |
| } |
| |
| /** |
| * readImpl accepts a callback to process the uid entry. readDeltaImpl needs to store the last |
| * seen results while processing the buffer, while readAbsolute returns the absolute value read |
| * from the buffer without storing. So readImpl contains the common logic of the two, leaving |
| * the difference to a processUid function. |
| * |
| * @param processUid the callback function to process the uid entry in the buffer. |
| */ |
| private void readImpl(Consumer<IntBuffer> processUid) { |
| synchronized (mProcReader) { |
| ByteBuffer bytes = mProcReader.readBytes(); |
| if (bytes == null || bytes.remaining() <= 4) { |
| // Error already logged in mProcReader. |
| return; |
| } |
| if ((bytes.remaining() & 3) != 0) { |
| Slog.wtf(TAG, "Cannot parse freq time proc bytes to int: " + bytes.remaining()); |
| return; |
| } |
| IntBuffer buf = bytes.asIntBuffer(); |
| final int freqs = buf.get(); |
| if (freqs != mCpuFreqsCount) { |
| Slog.wtf(TAG, "Cpu freqs expect " + mCpuFreqsCount + " , got " + freqs); |
| return; |
| } |
| if (buf.remaining() % (freqs + 1) != 0) { |
| Slog.wtf(TAG, "Freq time format error: " + buf.remaining() + " / " + (freqs + 1)); |
| return; |
| } |
| int numUids = buf.remaining() / (freqs + 1); |
| for (int i = 0; i < numUids; i++) { |
| processUid.accept(buf); |
| } |
| if (DEBUG) { |
| Slog.d(TAG, "Read uids: #" + numUids); |
| } |
| } |
| } |
| |
| public void removeUid(int uid) { |
| mLastUidCpuFreqTimeMs.delete(uid); |
| } |
| |
| public void removeUidsInRange(int startUid, int endUid) { |
| mLastUidCpuFreqTimeMs.put(startUid, null); |
| mLastUidCpuFreqTimeMs.put(endUid, null); |
| final int firstIndex = mLastUidCpuFreqTimeMs.indexOfKey(startUid); |
| final int lastIndex = mLastUidCpuFreqTimeMs.indexOfKey(endUid); |
| mLastUidCpuFreqTimeMs.removeAtRange(firstIndex, lastIndex - firstIndex + 1); |
| } |
| |
| /** |
| * Extracts no. of cpu clusters and no. of freqs in each of these clusters from the freqs |
| * read from the proc file. |
| * |
| * We need to assume that freqs in each cluster are strictly increasing. |
| * For e.g. if the freqs read from proc file are: 12, 34, 15, 45, 12, 15, 52. Then it means |
| * there are 3 clusters: (12, 34), (15, 45), (12, 15, 52) |
| * |
| * @return an IntArray filled with no. of freqs in each cluster. |
| */ |
| private IntArray extractClusterInfoFromProcFileFreqs() { |
| final IntArray numClusterFreqs = new IntArray(); |
| int freqsFound = 0; |
| for (int i = 0; i < mCpuFreqsCount; ++i) { |
| freqsFound++; |
| if (i + 1 == mCpuFreqsCount || mCpuFreqs[i + 1] <= mCpuFreqs[i]) { |
| numClusterFreqs.add(freqsFound); |
| freqsFound = 0; |
| } |
| } |
| return numClusterFreqs; |
| } |
| } |