From 3822882b32d9b1b803aaff9b657a91d680f1d0f9 Mon Sep 17 00:00:00 2001
From: "Torne (Richard Coles)" <torne@google.com>
Date: Wed, 13 Aug 2014 17:11:45 +0100
Subject: [PATCH] Add trace events to WebView startup.

Add system trace events for several interesting points during the
loading of the WebView APK so we can measure how much each part
contributes to startup time.

Bug: 16870075
Change-Id: Iadfd1881faea0377fa01313dddabb1d030962c5f
---
 core/java/android/webkit/WebViewFactory.java | 56 +++++++++++++-------
 1 file changed, 37 insertions(+), 19 deletions(-)

diff --git a/core/java/android/webkit/WebViewFactory.java b/core/java/android/webkit/WebViewFactory.java
index 23894ee7e43f7..ec589a5740ab9 100644
--- a/core/java/android/webkit/WebViewFactory.java
+++ b/core/java/android/webkit/WebViewFactory.java
@@ -29,6 +29,7 @@ import android.os.RemoteException;
 import android.os.ServiceManager;
 import android.os.StrictMode;
 import android.os.SystemProperties;
+import android.os.Trace;
 import android.text.TextUtils;
 import android.util.AndroidRuntimeException;
 import android.util.Log;
@@ -83,26 +84,38 @@ public final class WebViewFactory {
             // us honest and minimize usage of WebView internals when binding the proxy.
             if (sProviderInstance != null) return sProviderInstance;
 
-            loadNativeLibrary();
-
-            Class<WebViewFactoryProvider> providerClass;
+            Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "WebViewFactory.getProvider()");
             try {
-                providerClass = getFactoryClass();
-            } catch (ClassNotFoundException e) {
-                Log.e(LOGTAG, "error loading provider", e);
-                throw new AndroidRuntimeException(e);
-            }
+                Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "WebViewFactory.loadNativeLibrary()");
+                loadNativeLibrary();
+                Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW);
 
-            StrictMode.ThreadPolicy oldPolicy = StrictMode.allowThreadDiskReads();
-            try {
-                sProviderInstance = providerClass.newInstance();
-                if (DEBUG) Log.v(LOGTAG, "Loaded provider: " + sProviderInstance);
-                return sProviderInstance;
-            } catch (Exception e) {
-                Log.e(LOGTAG, "error instantiating provider", e);
-                throw new AndroidRuntimeException(e);
+                Class<WebViewFactoryProvider> providerClass;
+                Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "WebViewFactory.getFactoryClass()");
+                try {
+                    providerClass = getFactoryClass();
+                } catch (ClassNotFoundException e) {
+                    Log.e(LOGTAG, "error loading provider", e);
+                    throw new AndroidRuntimeException(e);
+                } finally {
+                    Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW);
+                }
+
+                StrictMode.ThreadPolicy oldPolicy = StrictMode.allowThreadDiskReads();
+                Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "providerClass.newInstance()");
+                try {
+                    sProviderInstance = providerClass.newInstance();
+                    if (DEBUG) Log.v(LOGTAG, "Loaded provider: " + sProviderInstance);
+                    return sProviderInstance;
+                } catch (Exception e) {
+                    Log.e(LOGTAG, "error instantiating provider", e);
+                    throw new AndroidRuntimeException(e);
+                } finally {
+                    Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW);
+                    StrictMode.setThreadPolicy(oldPolicy);
+                }
             } finally {
-                StrictMode.setThreadPolicy(oldPolicy);
+                Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW);
             }
         }
     }
@@ -122,8 +135,13 @@ public final class WebViewFactory {
             initialApplication.getAssets().addAssetPath(
                     webViewContext.getApplicationInfo().sourceDir);
             ClassLoader clazzLoader = webViewContext.getClassLoader();
-            return (Class<WebViewFactoryProvider>) Class.forName(CHROMIUM_WEBVIEW_FACTORY, true,
-                                                                 clazzLoader);
+            Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "Class.forName()");
+            try {
+                return (Class<WebViewFactoryProvider>) Class.forName(CHROMIUM_WEBVIEW_FACTORY, true,
+                                                                     clazzLoader);
+            } finally {
+                Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW);
+            }
         } catch (PackageManager.NameNotFoundException e) {
             // If the package doesn't exist, then try loading the null WebView instead.
             // If that succeeds, then this is a device without WebView support; if it fails then