1/*
2 * Copyright (C) 2015 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
17import java.io.File;
18import java.io.IOException;
19import java.lang.reflect.Method;
20
21/**
22 * Controls deoptimization using dalvik.system.VMDebug class.
23 */
24public class DeoptimizationController {
25  private static final String TEMP_FILE_NAME_PREFIX = "test";
26  private static final String TEMP_FILE_NAME_SUFFIX = ".trace";
27
28  private static File createTempFile() throws Exception {
29    try {
30      return  File.createTempFile(TEMP_FILE_NAME_PREFIX, TEMP_FILE_NAME_SUFFIX);
31    } catch (IOException e) {
32      System.setProperty("java.io.tmpdir", "/data/local/tmp");
33      try {
34        return File.createTempFile(TEMP_FILE_NAME_PREFIX, TEMP_FILE_NAME_SUFFIX);
35      } catch (IOException e2) {
36        System.setProperty("java.io.tmpdir", "/sdcard");
37        return File.createTempFile(TEMP_FILE_NAME_PREFIX, TEMP_FILE_NAME_SUFFIX);
38      }
39    }
40  }
41
42  public static void startDeoptimization() {
43    File tempFile = null;
44    try {
45      tempFile = createTempFile();
46      String tempFileName = tempFile.getPath();
47
48      VMDebug.startMethodTracing(tempFileName, 0, 0, false, 1000);
49      if (VMDebug.getMethodTracingMode() == 0) {
50        throw new IllegalStateException("Not tracing.");
51      }
52    } catch (Exception exc) {
53      exc.printStackTrace(System.err);
54    } finally {
55      if (tempFile != null) {
56        tempFile.delete();
57      }
58    }
59  }
60
61  public static void stopDeoptimization() {
62    try {
63      VMDebug.stopMethodTracing();
64      if (VMDebug.getMethodTracingMode() != 0) {
65        throw new IllegalStateException("Still tracing.");
66      }
67    } catch (Exception exc) {
68      exc.printStackTrace(System.err);
69    }
70  }
71
72  private static class VMDebug {
73    private static final Method startMethodTracingMethod;
74    private static final Method stopMethodTracingMethod;
75    private static final Method getMethodTracingModeMethod;
76
77    static {
78      try {
79        Class<?> c = Class.forName("dalvik.system.VMDebug");
80        startMethodTracingMethod = c.getDeclaredMethod("startMethodTracing", String.class,
81            Integer.TYPE, Integer.TYPE, Boolean.TYPE, Integer.TYPE);
82        stopMethodTracingMethod = c.getDeclaredMethod("stopMethodTracing");
83        getMethodTracingModeMethod = c.getDeclaredMethod("getMethodTracingMode");
84      } catch (Exception e) {
85        throw new RuntimeException(e);
86      }
87    }
88
89    public static void startMethodTracing(String filename, int bufferSize, int flags,
90        boolean samplingEnabled, int intervalUs) throws Exception {
91      startMethodTracingMethod.invoke(null, filename, bufferSize, flags, samplingEnabled,
92          intervalUs);
93    }
94    public static void stopMethodTracing() throws Exception {
95      stopMethodTracingMethod.invoke(null);
96    }
97    public static int getMethodTracingMode() throws Exception {
98      return (int) getMethodTracingModeMethod.invoke(null);
99    }
100  }
101}
102