Merge "Add Zygote.startChildZygote() to fork a new process that itself is a zygote." (554cfd1f) · Commits · e / os / android_frameworks_base

core/java/android/os/ChildZygoteProcess.java

0 → 100644

+44 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2018 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 android.os;

		import android.net.LocalSocketAddress;

		/**
		* Represents a connection to a child-zygote process. A child-zygote is spawend from another
		* zygote process using {@link startChildZygote()}.
		*
		* {@hide}
		*/
		public class ChildZygoteProcess extends ZygoteProcess {
		/**
		* The PID of the child zygote process.
		*/
		private final int mPid;

		ChildZygoteProcess(LocalSocketAddress socketAddress, int pid) {
		super(socketAddress, null);
		mPid = pid;
		}

		/**
		* Returns the PID of the child-zygote process.
		*/
		public int getPid() {
		return mPid;
		}
		}

core/java/android/os/ZygoteProcess.java

+54 −1

Original line number	Diff line number	Diff line
		@@ -33,6 +33,7 @@ import java.nio.charset.StandardCharsets;
		import java.util.ArrayList;
		import java.util.Arrays;
		import java.util.List;
		import java.util.UUID;

		/package/ class ZygoteStartFailedEx extends Exception {
		ZygoteStartFailedEx(String s) {
		@@ -217,7 +218,8 @@ public class ZygoteProcess {
		try {
		return startViaZygote(processClass, niceName, uid, gid, gids,
		runtimeFlags, mountExternal, targetSdkVersion, seInfo,
		abi, instructionSet, appDataDir, invokeWith, zygoteArgs);
		abi, instructionSet, appDataDir, invokeWith, false /* startChildZygote */,
		zygoteArgs);
		} catch (ZygoteStartFailedEx ex) {
		Log.e(LOG_TAG,
		"Starting VM process through Zygote failed");
		@@ -333,6 +335,8 @@ public class ZygoteProcess {
		* @param abi the ABI the process should use.
		* @param instructionSet null-ok the instruction set to use.
		* @param appDataDir null-ok the data directory of the app.
		* @param startChildZygote Start a sub-zygote. This creates a new zygote process
		* that has its state cloned from this zygote process.
		* @param extraArgs Additional arguments to supply to the zygote process.
		* @return An object that describes the result of the attempt to start the process.
		* @throws ZygoteStartFailedEx if process start failed for any reason
		@@ -348,6 +352,7 @@ public class ZygoteProcess {
		String instructionSet,
		String appDataDir,
		String invokeWith,
		boolean startChildZygote,
		String[] extraArgs)
		throws ZygoteStartFailedEx {
		ArrayList<String> argsForZygote = new ArrayList<String>();
		@@ -404,6 +409,10 @@ public class ZygoteProcess {
		argsForZygote.add(invokeWith);
		}

		if (startChildZygote) {
		argsForZygote.add("--start-child-zygote");
		}

		argsForZygote.add(processClass);

		if (extraArgs != null) {
		@@ -417,6 +426,18 @@ public class ZygoteProcess {
		}
		}

		/**
		* Closes the connections to the zygote, if they exist.
		*/
		public void close() {
		if (primaryZygoteState != null) {
		primaryZygoteState.close();
		}
		if (secondaryZygoteState != null) {
		secondaryZygoteState.close();
		}
		}

		/**
		* Tries to establish a connection to the zygote that handles a given {@code abi}. Might block
		* and retry if the zygote is unresponsive. This method is a no-op if a connection is
		@@ -549,4 +570,36 @@ public class ZygoteProcess {
		}
		Slog.wtf(LOG_TAG, "Failed to connect to Zygote through socket " + address.getName());
		}

		/**
		* Starts a new zygote process as a child of this zygote. This is used to create
		* secondary zygotes that inherit data from the zygote that this object
		* communicates with. This returns a new ZygoteProcess representing a connection
		* to the newly created zygote. Throws an exception if the zygote cannot be started.
		*/
		public ChildZygoteProcess startChildZygote(final String processClass,
		final String niceName,
		int uid, int gid, int[] gids,
		int runtimeFlags,
		String seInfo,
		String abi,
		String instructionSet) {
		// Create an unguessable address in the global abstract namespace.
		final LocalSocketAddress serverAddress = new LocalSocketAddress(
		processClass + "/" + UUID.randomUUID().toString());

		final String[] extraArgs = {Zygote.CHILD_ZYGOTE_SOCKET_NAME_ARG + serverAddress.getName()};

		Process.ProcessStartResult result;
		try {
		result = startViaZygote(processClass, niceName, uid, gid,
		gids, runtimeFlags, 0 /* mountExternal /, 0 / targetSdkVersion */, seInfo,
		abi, instructionSet, null /* appDataDir /, null / invokeWith */,
		true /* startChildZygote */, extraArgs);
		} catch (ZygoteStartFailedEx ex) {
		throw new RuntimeException("Starting child-zygote through Zygote failed", ex);
		}

		return new ChildZygoteProcess(serverAddress, result.pid);
		}
		}

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

+1 −1

Original line number	Diff line number	Diff line
		@@ -230,7 +230,7 @@ public class RuntimeInit {
		* @param argv Argument vector for main()
		* @param classLoader the classLoader to load {@className} with
		*/
		private static Runnable findStaticMain(String className, String[] argv,
		protected static Runnable findStaticMain(String className, String[] argv,
		ClassLoader classLoader) {
		Class<?> cl;

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

+1 −1

Original line number	Diff line number	Diff line
		@@ -129,7 +129,7 @@ class WebViewZygoteInit {

		final Runnable caller;
		try {
		sServer.registerServerSocket("webview_zygote");
		sServer.registerServerSocketFromEnv("webview_zygote");
		// The select loop returns early in the child process after a fork and
		// loops forever in the zygote.
		caller = sServer.runSelectLoop(TextUtils.join(",", Build.SUPPORTED_ABIS));

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

+14 −5

Original line number	Diff line number	Diff line
		@@ -71,6 +71,13 @@ public final class Zygote {

		private static final ZygoteHooks VM_HOOKS = new ZygoteHooks();

		/**
		* An extraArg passed when a zygote process is forking a child-zygote, specifying a name
		* in the abstract socket namespace. This socket name is what the new child zygote
		* should listen for connections on.
		*/
		public static final String CHILD_ZYGOTE_SOCKET_NAME_ARG = "--zygote-socket=";

		private Zygote() {}

		/** Called for some security initialization before any fork. */
		@@ -102,6 +109,8 @@ public final class Zygote {
		* @param fdsToIgnore null-ok an array of ints, either null or holding
		* one or more POSIX file descriptor numbers that are to be ignored
		* in the file descriptor table check.
		* @param startChildZygote if true, the new child process will itself be a
		* new zygote process.
		* @param instructionSet null-ok the instruction set to use.
		* @param appDataDir null-ok the data directory of the app.
		*
		@@ -110,13 +119,13 @@ public final class Zygote {
		*/
		public static int forkAndSpecialize(int uid, int gid, int[] gids, int runtimeFlags,
		int[][] rlimits, int mountExternal, String seInfo, String niceName, int[] fdsToClose,
		int[] fdsToIgnore, String instructionSet, String appDataDir) {
		int[] fdsToIgnore, boolean startChildZygote, String instructionSet, String appDataDir) {
		VM_HOOKS.preFork();
		// Resets nice priority for zygote process.
		resetNicePriority();
		int pid = nativeForkAndSpecialize(
		uid, gid, gids, runtimeFlags, rlimits, mountExternal, seInfo, niceName, fdsToClose,
		fdsToIgnore, instructionSet, appDataDir);
		fdsToIgnore, startChildZygote, instructionSet, appDataDir);
		// Enable tracing as soon as possible for the child process.
		if (pid == 0) {
		Trace.setTracingEnabled(true, runtimeFlags);
		@@ -130,7 +139,7 @@ public final class Zygote {

		native private static int nativeForkAndSpecialize(int uid, int gid, int[] gids,int runtimeFlags,
		int[][] rlimits, int mountExternal, String seInfo, String niceName, int[] fdsToClose,
		int[] fdsToIgnore, String instructionSet, String appDataDir);
		int[] fdsToIgnore, boolean startChildZygote, String instructionSet, String appDataDir);

		/**
		* Called to do any initialization before starting an application.
		@@ -190,8 +199,8 @@ public final class Zygote {
		native protected static void nativeUnmountStorageOnInit();

		private static void callPostForkChildHooks(int runtimeFlags, boolean isSystemServer,
		String instructionSet) {
		VM_HOOKS.postForkChild(runtimeFlags, isSystemServer, instructionSet);
		boolean isZygote, String instructionSet) {
		VM_HOOKS.postForkChild(runtimeFlags, isSystemServer, isZygote, instructionSet);
		}

		/**