1481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown/* 2481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * Copyright (C) 2012 The Android Open Source Project 3481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * 4481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * Licensed under the Apache License, Version 2.0 (the "License"); 5481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * you may not use this file except in compliance with the License. 6481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * You may obtain a copy of the License at 7481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * 8481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * http://www.apache.org/licenses/LICENSE-2.0 9481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * 10481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * Unless required by applicable law or agreed to in writing, software 11481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * distributed under the License is distributed on an "AS IS" BASIS, 12481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * See the License for the specific language governing permissions and 14481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * limitations under the License. 15481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown */ 16481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown 17481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brownpackage android.os; 18481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown 19d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFaddenimport android.util.Log; 20d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden 21481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown/** 22481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * Writes trace events to the kernel trace buffer. These trace events can be 23481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * collected using the "atrace" program for offline analysis. 24481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * 25481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * This tracing mechanism is independent of the method tracing mechanism 26481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * offered by {@link Debug#startMethodTracing}. In particular, it enables 27481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * tracing of events that occur across processes. 28481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * 29481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * @hide 30481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown */ 31481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brownpublic final class Trace { 32d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden private static final String TAG = "Trace"; 33d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden 34481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown // These tags must be kept in sync with frameworks/native/include/utils/Trace.h. 35481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown public static final long TRACE_TAG_NEVER = 0; 36481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown public static final long TRACE_TAG_ALWAYS = 1L << 0; 37481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown public static final long TRACE_TAG_GRAPHICS = 1L << 1; 38481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown public static final long TRACE_TAG_INPUT = 1L << 2; 39481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown public static final long TRACE_TAG_VIEW = 1L << 3; 40192a65e9f6ebdc452520e19f95c68c270b3f96daChris Craik public static final long TRACE_TAG_WEBVIEW = 1L << 4; 411ded0b1f6af65c2f95f8327f7f3df4cee1bf2346Dianne Hackborn public static final long TRACE_TAG_WINDOW_MANAGER = 1L << 5; 421ded0b1f6af65c2f95f8327f7f3df4cee1bf2346Dianne Hackborn public static final long TRACE_TAG_ACTIVITY_MANAGER = 1L << 6; 4309b45a3ad96379b4181d32f8391f63e9c57dc316Andy Stadler public static final long TRACE_TAG_SYNC_MANAGER = 1L << 7; 44ed853fc4e0ba8ce0692d65064e12cf129b5d1f3eGlenn Kasten public static final long TRACE_TAG_AUDIO = 1L << 8; 4524dae6c611455ec38675554033e4d18810d77d6cJamie Gennis public static final long TRACE_TAG_VIDEO = 1L << 9; 469c0d9cf25ffdf4f6545e489b22ba621bf0b7ba29Eino-Ville Talvala public static final long TRACE_TAG_CAMERA = 1L << 10; 47481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown 4883e6eb11d7ec24e7c363beccab0806989ad89ec5Dianne Hackborn public static final int TRACE_FLAGS_START_BIT = 1; 4983e6eb11d7ec24e7c363beccab0806989ad89ec5Dianne Hackborn public static final String[] TRACE_TAGS = { 5083e6eb11d7ec24e7c363beccab0806989ad89ec5Dianne Hackborn "Graphics", "Input", "View", "WebView", "Window Manager", 519c0d9cf25ffdf4f6545e489b22ba621bf0b7ba29Eino-Ville Talvala "Activity Manager", "Sync Manager", "Audio", "Video", "Camera", 5283e6eb11d7ec24e7c363beccab0806989ad89ec5Dianne Hackborn }; 5383e6eb11d7ec24e7c363beccab0806989ad89ec5Dianne Hackborn 5483e6eb11d7ec24e7c363beccab0806989ad89ec5Dianne Hackborn public static final String PROPERTY_TRACE_TAG_ENABLEFLAGS = "debug.atrace.tags.enableflags"; 5583e6eb11d7ec24e7c363beccab0806989ad89ec5Dianne Hackborn 56d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden // This works as a "not ready" flag because TRACE_TAG_ALWAYS is always set. 57d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden private static final long TRACE_FLAGS_NOT_READY = 0; 58d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden 59d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden // Must be volatile to avoid word tearing. 60d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden private static volatile long sEnabledTags = TRACE_FLAGS_NOT_READY; 61481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown 62481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown private static native long nativeGetEnabledTags(); 63481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown private static native void nativeTraceCounter(long tag, String name, int value); 64481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown private static native void nativeTraceBegin(long tag, String name); 65481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown private static native void nativeTraceEnd(long tag); 66481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown 67a53de0629f3b94472c0f160f5bbe1090b020feabDianne Hackborn static { 68d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden // We configure two separate change callbacks, one in Trace.cpp and one here. The 69d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden // native callback reads the tags from the system property, and this callback 70d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden // reads the value that the native code retrieved. It's essential that the native 71d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden // callback executes first. 72d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden // 73d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden // The system provides ordering through a priority level. Callbacks made through 74d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden // SystemProperties.addChangeCallback currently have a negative priority, while 75d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden // our native code is using a priority of zero. 76a53de0629f3b94472c0f160f5bbe1090b020feabDianne Hackborn SystemProperties.addChangeCallback(new Runnable() { 77a53de0629f3b94472c0f160f5bbe1090b020feabDianne Hackborn @Override public void run() { 78d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden cacheEnabledTags(); 79a53de0629f3b94472c0f160f5bbe1090b020feabDianne Hackborn } 80a53de0629f3b94472c0f160f5bbe1090b020feabDianne Hackborn }); 81a53de0629f3b94472c0f160f5bbe1090b020feabDianne Hackborn } 82a53de0629f3b94472c0f160f5bbe1090b020feabDianne Hackborn 83481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown private Trace() { 84481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown } 85481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown 86481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown /** 87d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden * Caches a copy of the enabled-tag bits. The "master" copy is held by the native code, 88d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden * and comes from the PROPERTY_TRACE_TAG_ENABLEFLAGS property. 89d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden * <p> 90d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden * If the native code hasn't yet read the property, we will cause it to do one-time 91d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden * initialization. We don't want to do this during class init, because this class is 92d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden * preloaded, so all apps would be stuck with whatever the zygote saw. (The zygote 93d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden * doesn't see the system-property update broadcasts.) 94d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden * <p> 95d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden * We want to defer initialization until the first use by an app, post-zygote. 96d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden * <p> 97d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden * We're okay if multiple threads call here simultaneously -- the native state is 98d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden * synchronized, and sEnabledTags is volatile (prevents word tearing). 99d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden */ 100d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden private static long cacheEnabledTags() { 101d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden long tags = nativeGetEnabledTags(); 102d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden if (tags == TRACE_FLAGS_NOT_READY) { 103d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden Log.w(TAG, "Unexpected value from nativeGetEnabledTags: " + tags); 104d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden // keep going 105d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden } 106d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden sEnabledTags = tags; 107d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden return tags; 108d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden } 109d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden 110d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden /** 111481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * Returns true if a trace tag is enabled. 112481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * 113481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * @param traceTag The trace tag to check. 114481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * @return True if the trace tag is valid. 115481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown */ 116481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown public static boolean isTagEnabled(long traceTag) { 117d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden long tags = sEnabledTags; 118d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden if (tags == TRACE_FLAGS_NOT_READY) { 119d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden tags = cacheEnabledTags(); 120d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden } 121d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden return (tags & traceTag) != 0; 122481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown } 123481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown 124481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown /** 125481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * Writes trace message to indicate the value of a given counter. 126481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * 127481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * @param traceTag The trace tag. 128481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * @param counterName The counter name to appear in the trace. 129481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * @param counterValue The counter value. 130481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown */ 131481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown public static void traceCounter(long traceTag, String counterName, int counterValue) { 132d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden if (isTagEnabled(traceTag)) { 133481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown nativeTraceCounter(traceTag, counterName, counterValue); 134481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown } 135481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown } 136481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown 137481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown /** 138481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * Writes a trace message to indicate that a given method has begun. 139481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * Must be followed by a call to {@link #traceEnd} using the same tag. 140481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * 141481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * @param traceTag The trace tag. 142481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * @param methodName The method name to appear in the trace. 143481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown */ 144481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown public static void traceBegin(long traceTag, String methodName) { 145d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden if (isTagEnabled(traceTag)) { 146481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown nativeTraceBegin(traceTag, methodName); 147481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown } 148481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown } 149481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown 150481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown /** 151481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * Writes a trace message to indicate that the current method has ended. 152481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * Must be called exactly once for each call to {@link #traceBegin} using the same tag. 153481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * 154481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown * @param traceTag The trace tag. 155481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown */ 156481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown public static void traceEnd(long traceTag) { 157d11ca4dd2ca90e1412b24f4526a56f7b963054a8Andy McFadden if (isTagEnabled(traceTag)) { 158481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown nativeTraceEnd(traceTag); 159481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown } 160481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown } 161481c1570dc5cdf58265b53f657801709dd05d1dfJeff Brown} 162