Merge "Precreate the classloader for the WebView." (566b1c80) · Commits · e / os / android_frameworks_base

core/java/android/app/ApplicationLoaders.java

+17 −2

Original line number	Diff line number	Diff line
		@@ -16,17 +16,19 @@

		package android.app;

		import android.os.Build;
		import android.os.Trace;
		import android.util.ArrayMap;
		import com.android.internal.os.PathClassLoaderFactory;
		import dalvik.system.PathClassLoader;

		class ApplicationLoaders {
		/** @hide */
		public class ApplicationLoaders {
		public static ApplicationLoaders getDefault() {
		return gApplicationLoaders;
		}

		public ClassLoader getClassLoader(String zip, int targetSdkVersion, boolean isBundled,
		ClassLoader getClassLoader(String zip, int targetSdkVersion, boolean isBundled,
		String librarySearchPath, String libraryPermittedPath,
		ClassLoader parent) {
		/*
		@@ -80,6 +82,19 @@ class ApplicationLoaders {
		}
		}

		/**
		* Creates a classloader for the WebView APK and places it in the cache of loaders maintained
		* by this class. This is used in the WebView zygote, where its presence in the cache speeds up
		* startup and enables memory sharing.
		*/
		public ClassLoader createAndCacheWebViewClassLoader(String packagePath, String libsPath) {
		// The correct paths are calculated by WebViewZygote in the system server and passed to
		// us here. We hardcode the other parameters: WebView always targets the current SDK,
		// does not need to use non-public system libraries, and uses the base classloader as its
		// parent to permit usage of the cache.
		return getClassLoader(packagePath, Build.VERSION.SDK_INT, false, libsPath, null, null);
		}

		private static native void setupVulkanLayerPath(ClassLoader classLoader, String librarySearchPath);

		/**

core/java/android/app/LoadedApk.java

+32 −28

Original line number	Diff line number	Diff line
		@@ -339,6 +339,10 @@ public final class LoadedApk {
		* concatenation of both apps' shared library lists.
		*/

		String[] instrumentationLibs = null;
		// activityThread will be null when called from the WebView zygote; just assume
		// no instrumentation applies in this case.
		if (activityThread != null) {
		String instrumentationPackageName = activityThread.mInstrumentationPackageName;
		String instrumentationAppDir = activityThread.mInstrumentationAppDir;
		String[] instrumentationSplitAppDirs = activityThread.mInstrumentationSplitAppDirs;
		@@ -347,7 +351,6 @@ public final class LoadedApk {
		String instrumentedAppDir = activityThread.mInstrumentedAppDir;
		String[] instrumentedSplitAppDirs = activityThread.mInstrumentedSplitAppDirs;
		String instrumentedLibDir = activityThread.mInstrumentedLibDir;
		String[] instrumentationLibs = null;

		if (appDir.equals(instrumentationAppDir)
		\|\| appDir.equals(instrumentedAppDir)) {
		@@ -374,6 +377,7 @@ public final class LoadedApk {
		instrumentationLibs = getLibrariesFor(instrumentationPackageName);
		}
		}
		}

		if (outLibPaths != null) {
		if (outLibPaths.isEmpty()) {

core/java/android/webkit/WebViewFactory.java

+3 −1

Original line number	Diff line number	Diff line
		@@ -56,7 +56,9 @@ import java.util.zip.ZipFile;
		@SystemApi
		public final class WebViewFactory {

		private static final String CHROMIUM_WEBVIEW_FACTORY =
		// visible for WebViewZygoteInit to look up the class by reflection and call preloadInZygote.
		/** @hide */
		public static final String CHROMIUM_WEBVIEW_FACTORY =
		"com.android.webview.chromium.WebViewChromiumFactoryProvider";

		private static final String NULL_WEBVIEW_FACTORY =

core/java/android/webkit/WebViewZygote.java

+20 −5

Original line number	Diff line number	Diff line
		@@ -16,14 +16,19 @@

		package android.webkit;

		import android.app.LoadedApk;
		import android.content.pm.PackageInfo;
		import android.os.Build;
		import android.os.SystemService;
		import android.os.ZygoteProcess;
		import android.text.TextUtils;
		import android.util.Log;

		import java.io.File;
		import java.io.IOException;
		import java.util.ArrayList;
		import java.util.Arrays;
		import java.util.List;
		import java.util.concurrent.TimeoutException;

		/** @hide */
		@@ -122,11 +127,21 @@ public class WebViewZygote {
		try {
		sZygote = new ZygoteProcess("webview_zygote", null);

		String packagePath = sPackage.applicationInfo.sourceDir;
		String libsPath = sPackage.applicationInfo.nativeLibraryDir;

		Log.d(LOGTAG, "Preloading package " + packagePath + " " + libsPath);
		sZygote.preloadPackageForAbi(packagePath, libsPath, Build.SUPPORTED_ABIS[0]);
		// All the work below is usually done by LoadedApk, but the zygote can't talk to
		// PackageManager or construct a LoadedApk since it's single-threaded pre-fork, so
		// doesn't have an ActivityThread and can't use Binder.
		// Instead, figure out the paths here, in the system server where we have access to
		// the package manager. Reuse the logic from LoadedApk to determine the correct
		// paths and pass them to the zygote as strings.
		final List<String> zipPaths = new ArrayList<>(10);
		final List<String> libPaths = new ArrayList<>(10);
		LoadedApk.makePaths(null, sPackage.applicationInfo, zipPaths, libPaths);
		final String librarySearchPath = TextUtils.join(File.pathSeparator, libPaths);
		final String zip = (zipPaths.size() == 1) ? zipPaths.get(0) :
		TextUtils.join(File.pathSeparator, zipPaths);

		Log.d(LOGTAG, "Preloading package " + zip + " " + librarySearchPath);
		sZygote.preloadPackageForAbi(zip, librarySearchPath, Build.SUPPORTED_ABIS[0]);
		} catch (Exception e) {
		Log.e(LOGTAG, "Error connecting to " + serviceName, e);
		sZygote = null;

core/java/com/android/internal/os/WebViewZygoteInit.java

+24 −1

Original line number	Diff line number	Diff line
		@@ -16,14 +16,17 @@

		package com.android.internal.os;

		import android.app.ApplicationLoaders;
		import android.net.LocalSocket;
		import android.os.Build;
		import android.system.ErrnoException;
		import android.system.Os;
		import android.text.TextUtils;
		import android.util.Log;
		import android.webkit.WebViewFactory;

		import java.io.IOException;
		import java.lang.reflect.InvocationTargetException;

		/**
		* Startup class for the WebView zygote process.
		@@ -52,7 +55,27 @@ class WebViewZygoteInit {

		@Override
		protected boolean handlePreloadPackage(String packagePath, String libsPath) {
		// TODO: Use preload information to setup the ClassLoader.
		// Ask ApplicationLoaders to create and cache a classloader for the WebView APK so that
		// our children will reuse the same classloader instead of creating their own.
		// This enables us to preload Java and native code in the webview zygote process and
		// have the preloaded versions actually be used post-fork.
		ClassLoader loader = ApplicationLoaders.getDefault().createAndCacheWebViewClassLoader(
		packagePath, libsPath);

		// Once we have the classloader, look up the WebViewFactoryProvider implementation and
		// call preloadInZygote() on it to give it the opportunity to preload the native library
		// and perform any other initialisation work that should be shared among the children.
		try {
		Class providerClass = Class.forName(WebViewFactory.CHROMIUM_WEBVIEW_FACTORY, true,
		loader);
		Object result = providerClass.getMethod("preloadInZygote").invoke(null);
		if (!((Boolean)result).booleanValue()) {
		Log.e(TAG, "preloadInZygote returned false");
		}
		} catch (ClassNotFoundException \| NoSuchMethodException \| SecurityException \|
		IllegalAccessException \| InvocationTargetException e) {
		Log.e(TAG, "Exception while preloading package", e);
		}
		return false;
		}
		}