| /* |
| * 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.os.Process; |
| import android.os.StrictMode; |
| import android.os.SystemClock; |
| import android.util.Slog; |
| |
| import com.android.internal.annotations.VisibleForTesting; |
| |
| import java.io.FileInputStream; |
| import java.util.Iterator; |
| |
| /** |
| * Reads and parses wakelock stats from the kernel (/proc/wakelocks). |
| */ |
| public class KernelWakelockReader { |
| private static final String TAG = "KernelWakelockReader"; |
| private static int sKernelWakelockUpdateVersion = 0; |
| private static final String sWakelockFile = "/proc/wakelocks"; |
| private static final String sWakeupSourceFile = "/d/wakeup_sources"; |
| |
| private static final int[] PROC_WAKELOCKS_FORMAT = new int[] { |
| Process.PROC_TAB_TERM|Process.PROC_OUT_STRING| // 0: name |
| Process.PROC_QUOTES, |
| Process.PROC_TAB_TERM|Process.PROC_OUT_LONG, // 1: count |
| Process.PROC_TAB_TERM, |
| Process.PROC_TAB_TERM, |
| Process.PROC_TAB_TERM, |
| Process.PROC_TAB_TERM|Process.PROC_OUT_LONG, // 5: totalTime |
| }; |
| |
| private static final int[] WAKEUP_SOURCES_FORMAT = new int[] { |
| Process.PROC_TAB_TERM|Process.PROC_OUT_STRING, // 0: name |
| Process.PROC_TAB_TERM|Process.PROC_COMBINE| |
| Process.PROC_OUT_LONG, // 1: count |
| Process.PROC_TAB_TERM|Process.PROC_COMBINE, |
| Process.PROC_TAB_TERM|Process.PROC_COMBINE, |
| Process.PROC_TAB_TERM|Process.PROC_COMBINE, |
| Process.PROC_TAB_TERM|Process.PROC_COMBINE, |
| Process.PROC_TAB_TERM|Process.PROC_COMBINE |
| |Process.PROC_OUT_LONG, // 6: totalTime |
| }; |
| |
| private final String[] mProcWakelocksName = new String[3]; |
| private final long[] mProcWakelocksData = new long[3]; |
| |
| /** |
| * Reads kernel wakelock stats and updates the staleStats with the new information. |
| * @param staleStats Existing object to update. |
| * @return the updated data. |
| */ |
| public final KernelWakelockStats readKernelWakelockStats(KernelWakelockStats staleStats) { |
| byte[] buffer = new byte[32*1024]; |
| int len = 0; |
| boolean wakeup_sources; |
| final long startTime = SystemClock.uptimeMillis(); |
| |
| final int oldMask = StrictMode.allowThreadDiskReadsMask(); |
| try { |
| FileInputStream is; |
| try { |
| is = new FileInputStream(sWakelockFile); |
| wakeup_sources = false; |
| } catch (java.io.FileNotFoundException e) { |
| try { |
| is = new FileInputStream(sWakeupSourceFile); |
| wakeup_sources = true; |
| } catch (java.io.FileNotFoundException e2) { |
| Slog.wtf(TAG, "neither " + sWakelockFile + " nor " + |
| sWakeupSourceFile + " exists"); |
| return null; |
| } |
| } |
| |
| int cnt; |
| while ((cnt = is.read(buffer, len, buffer.length - len)) > 0) { |
| len += cnt; |
| } |
| |
| is.close(); |
| } catch (java.io.IOException e) { |
| Slog.wtf(TAG, "failed to read kernel wakelocks", e); |
| return null; |
| } finally { |
| StrictMode.setThreadPolicyMask(oldMask); |
| } |
| |
| final long readTime = SystemClock.uptimeMillis() - startTime; |
| if (readTime > 100) { |
| Slog.w(TAG, "Reading wakelock stats took " + readTime + "ms"); |
| } |
| |
| if (len > 0) { |
| if (len >= buffer.length) { |
| Slog.wtf(TAG, "Kernel wake locks exceeded buffer size " + buffer.length); |
| } |
| int i; |
| for (i=0; i<len; i++) { |
| if (buffer[i] == '\0') { |
| len = i; |
| break; |
| } |
| } |
| } |
| return parseProcWakelocks(buffer, len, wakeup_sources, staleStats); |
| } |
| |
| /** |
| * Reads the wakelocks and updates the staleStats with the new information. |
| */ |
| @VisibleForTesting |
| public KernelWakelockStats parseProcWakelocks(byte[] wlBuffer, int len, boolean wakeup_sources, |
| final KernelWakelockStats staleStats) { |
| String name; |
| int count; |
| long totalTime; |
| int startIndex; |
| int endIndex; |
| |
| // Advance past the first line. |
| int i; |
| for (i = 0; i < len && wlBuffer[i] != '\n' && wlBuffer[i] != '\0'; i++); |
| startIndex = endIndex = i + 1; |
| |
| synchronized(this) { |
| sKernelWakelockUpdateVersion++; |
| while (endIndex < len) { |
| for (endIndex=startIndex; |
| endIndex < len && wlBuffer[endIndex] != '\n' && wlBuffer[endIndex] != '\0'; |
| endIndex++); |
| // Don't go over the end of the buffer, Process.parseProcLine might |
| // write to wlBuffer[endIndex] |
| if (endIndex > (len - 1) ) { |
| break; |
| } |
| |
| String[] nameStringArray = mProcWakelocksName; |
| long[] wlData = mProcWakelocksData; |
| // Stomp out any bad characters since this is from a circular buffer |
| // A corruption is seen sometimes that results in the vm crashing |
| // This should prevent crashes and the line will probably fail to parse |
| for (int j = startIndex; j < endIndex; j++) { |
| if ((wlBuffer[j] & 0x80) != 0) wlBuffer[j] = (byte) '?'; |
| } |
| boolean parsed = Process.parseProcLine(wlBuffer, startIndex, endIndex, |
| wakeup_sources ? WAKEUP_SOURCES_FORMAT : |
| PROC_WAKELOCKS_FORMAT, |
| nameStringArray, wlData, null); |
| |
| name = nameStringArray[0].trim(); |
| count = (int) wlData[1]; |
| |
| if (wakeup_sources) { |
| // convert milliseconds to microseconds |
| totalTime = wlData[2] * 1000; |
| } else { |
| // convert nanoseconds to microseconds with rounding. |
| totalTime = (wlData[2] + 500) / 1000; |
| } |
| |
| if (parsed && name.length() > 0) { |
| if (!staleStats.containsKey(name)) { |
| staleStats.put(name, new KernelWakelockStats.Entry(count, totalTime, |
| sKernelWakelockUpdateVersion)); |
| } else { |
| KernelWakelockStats.Entry kwlStats = staleStats.get(name); |
| if (kwlStats.mVersion == sKernelWakelockUpdateVersion) { |
| kwlStats.mCount += count; |
| kwlStats.mTotalTime += totalTime; |
| } else { |
| kwlStats.mCount = count; |
| kwlStats.mTotalTime = totalTime; |
| kwlStats.mVersion = sKernelWakelockUpdateVersion; |
| } |
| } |
| } else if (!parsed) { |
| try { |
| Slog.wtf(TAG, "Failed to parse proc line: " + |
| new String(wlBuffer, startIndex, endIndex - startIndex)); |
| } catch (Exception e) { |
| Slog.wtf(TAG, "Failed to parse proc line!"); |
| } |
| } |
| startIndex = endIndex + 1; |
| } |
| |
| // Don't report old data. |
| Iterator<KernelWakelockStats.Entry> itr = staleStats.values().iterator(); |
| while (itr.hasNext()) { |
| if (itr.next().mVersion != sKernelWakelockUpdateVersion) { |
| itr.remove(); |
| } |
| } |
| |
| staleStats.kernelWakelockVersion = sKernelWakelockUpdateVersion; |
| return staleStats; |
| } |
| } |
| } |