Merge "Reparent the webview_zygote to be a child of the main app_process zygote." am: 1c81aa6375

am: 486190f87b

Change-Id: I683dbbf730bfd02e43cb67bfcaa0df56d69c9796

cmds/webview_zygote/Android.mk

@@ -1,51 +0,0 @@
-#
-# Copyright (C) 2016 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.
-#
-
-LOCAL_PATH := $(call my-dir)
-include $(CLEAR_VARS)
-
-LOCAL_MODULE := webview_zygote
-
-LOCAL_SRC_FILES := webview_zygote.cpp
-
-LOCAL_CFLAGS := -Wall -Werror
-
-LOCAL_SHARED_LIBRARIES := \
-	libandroid_runtime \
-	libbinder \
-	liblog \
-	libcutils \
-	libutils
-
-LOCAL_LDFLAGS_32 := -Wl,--version-script,art/sigchainlib/version-script32.txt -Wl,--export-dynamic
-LOCAL_LDFLAGS_64 := -Wl,--version-script,art/sigchainlib/version-script64.txt -Wl,--export-dynamic
-
-LOCAL_WHOLE_STATIC_LIBRARIES := libsigchain
-
-LOCAL_INIT_RC := webview_zygote32.rc
-
-# Always include the 32-bit version of webview_zygote. If the target is 64-bit,
-# also include the 64-bit webview_zygote.
-ifeq ($(TARGET_SUPPORTS_64_BIT_APPS),true)
-	LOCAL_INIT_RC += webview_zygote64.rc
-endif
-
-LOCAL_MULTILIB := both
-
-LOCAL_MODULE_STEM_32 := webview_zygote32
-LOCAL_MODULE_STEM_64 := webview_zygote64
-
-include $(BUILD_EXECUTABLE)

cmds/webview_zygote/webview_zygote.cpp

@@ -1,76 +0,0 @@
-/*
- * Copyright (C) 2016 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.
- */
-
-
-#define LOG_TAG "WebViewZygote"
-
-#include <sys/prctl.h>
-
-#include <android_runtime/AndroidRuntime.h>
-#include <binder/IPCThreadState.h>
-#include <binder/ProcessState.h>
-#include <utils/Log.h>
-#include <utils/String8.h>
-#include <utils/Vector.h>
-
-namespace android {
-
-class WebViewRuntime : public AndroidRuntime {
-public:
-    WebViewRuntime(char* argBlockStart, size_t argBlockSize)
-        : AndroidRuntime(argBlockStart, argBlockSize) {}
-
-    ~WebViewRuntime() override {}
-
-    void onStarted() override {
-        // Nothing to do since this is a zygote server.
-    }
-
-    void onVmCreated(JNIEnv*) override {
-        // Nothing to do when the VM is created in the zygote.
-    }
-
-    void onZygoteInit() override {
-        // Called after a new process is forked.
-        sp<ProcessState> proc = ProcessState::self();
-        proc->startThreadPool();
-    }
-
-    void onExit(int code) override {
-        IPCThreadState::self()->stopProcess();
-        AndroidRuntime::onExit(code);
-    }
-};
-
-}  // namespace android
-
-int main(int argc, char* const argv[]) {
-    if (prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) < 0) {
-        LOG_ALWAYS_FATAL("PR_SET_NO_NEW_PRIVS failed: %s", strerror(errno));
-        return 12;
-    }
-
-    size_t argBlockSize = 0;
-    for (int i = 0; i < argc; ++i) {
-        argBlockSize += strlen(argv[i]) + 1;
-    }
-
-    android::WebViewRuntime runtime(argv[0], argBlockSize);
-    runtime.addOption("-Xzygote");
-
-    android::Vector<android::String8> args;
-    runtime.start("com.android.internal.os.WebViewZygoteInit", args, /*zygote=*/ true);
-}

cmds/webview_zygote/webview_zygote32.rc

@@ -1,22 +0,0 @@
-#
-# Copyright (C) 2016 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.
-#
-
-service webview_zygote32 /system/bin/webview_zygote32
-    user webview_zygote
-    socket webview_zygote stream 660 webview_zygote system
-
-on property:init.svc.zygote=stopped
-    stop webview_zygote32

cmds/webview_zygote/webview_zygote64.rc

@@ -1,22 +0,0 @@
-#
-# Copyright (C) 2016 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.
-#
-
-service webview_zygote64 /system/bin/webview_zygote64
-    user webview_zygote
-    socket webview_zygote stream 660 webview_zygote system
-
-on property:init.svc.zygote=stopped
-    stop webview_zygote64

core/java/android/webkit/WebViewZygote.java

@@ -20,29 +20,22 @@ import android.app.LoadedApk;
 import android.content.pm.ApplicationInfo;
 import android.content.pm.PackageInfo;
 import android.os.Build;
-import android.os.SystemService;
+import android.os.ChildZygoteProcess;
+import android.os.Process;
 import android.os.ZygoteProcess;
 import android.text.TextUtils;
-import android.util.AndroidRuntimeException;
 import android.util.Log;
 
 import com.android.internal.annotations.GuardedBy;
 
 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 */
 public class WebViewZygote {
     private static final String LOGTAG = "WebViewZygote";
 
-    private static final String WEBVIEW_ZYGOTE_SERVICE_32 = "webview_zygote32";
-    private static final String WEBVIEW_ZYGOTE_SERVICE_64 = "webview_zygote64";
-    private static final String WEBVIEW_ZYGOTE_SOCKET = "webview_zygote";
-
     /**
      * Lock object that protects all other static members.
      */
@@ -53,14 +46,7 @@ public class WebViewZygote {
      * is not running or is not connected.
      */
     @GuardedBy("sLock")
-    private static ZygoteProcess sZygote;
+    private static ChildZygoteProcess sZygote;
-
-    /**
-     * Variable that allows us to determine whether the WebView zygote Service has already been
-     * started.
-     */
-    @GuardedBy("sLock")
-    private static boolean sStartedService = false;
 
     /**
      * Information about the selected WebView package. This is set from #onWebViewProviderChanged().
@@ -86,7 +72,7 @@ public class WebViewZygote {
         synchronized (sLock) {
             if (sZygote != null) return sZygote;
 
-            waitForServiceStartAndConnect();
+            connectToZygoteIfNeededLocked();
             return sZygote;
         }
     }
@@ -108,21 +94,13 @@ public class WebViewZygote {
             sMultiprocessEnabled = enabled;
 
             // When toggling between multi-process being on/off, start or stop the
-            // service. If it is enabled and the zygote is not yet started, bring up the service.
+            // zygote. If it is enabled and the zygote is not yet started, launch it.
-            // Otherwise, bring down the service. The name may be null if the package
+            // Otherwise, kill it. The name may be null if the package information has
-            // information has not yet been resolved.
+            // not yet been resolved.
-            final String serviceName = getServiceNameLocked();
-            if (serviceName == null) return;
-
             if (enabled) {
-                if (!sStartedService) {
+                connectToZygoteIfNeededLocked();
-                    SystemService.start(serviceName);
-                    sStartedService = true;
-                }
             } else {
-                SystemService.stop(serviceName);
+                stopZygoteLocked();
-                sStartedService = false;
-                sZygote = null;
             }
         }
     }
@@ -138,53 +116,21 @@ public class WebViewZygote {
                 return;
             }
 
-            final String serviceName = getServiceNameLocked();
+            stopZygoteLocked();
-            sZygote = null;
-
-            // The service may enter the RUNNING state before it opens the socket,
-            // so connectToZygoteIfNeededLocked() may still fail.
-            if (SystemService.isStopped(serviceName)) {
-                SystemService.start(serviceName);
-            } else {
-                SystemService.restart(serviceName);
-            }
-            sStartedService = true;
-        }
-    }
-
-    private static void waitForServiceStartAndConnect() {
-        if (!sStartedService) {
-            throw new AndroidRuntimeException("Tried waiting for the WebView Zygote Service to " +
-                    "start running without first starting the service.");
-        }
-
-        String serviceName;
-        synchronized (sLock) {
-            serviceName = getServiceNameLocked();
-        }
-        try {
-            SystemService.waitForState(serviceName, SystemService.State.RUNNING, 5000);
-        } catch (TimeoutException e) {
-            Log.e(LOGTAG, "Timed out waiting for " + serviceName);
-            return;
-        }
-
-        synchronized (sLock) {
-            connectToZygoteIfNeededLocked();
         }
     }
 
     @GuardedBy("sLock")
-    private static String getServiceNameLocked() {
+    private static void stopZygoteLocked() {
-        if (sPackage == null)
+        if (sZygote != null) {
-            return null;
+            // Close the connection and kill the zygote process. This will not cause
-
+            // child processes to be killed by itself. But if this is called in response to
-        if (Arrays.asList(Build.SUPPORTED_64_BIT_ABIS).contains(
+            // setMultiprocessEnabled() or onWebViewProviderChanged(), the WebViewUpdater
-                    sPackage.applicationInfo.primaryCpuAbi)) {
+            // will kill all processes that depend on the WebView package.
-            return WEBVIEW_ZYGOTE_SERVICE_64;
+            sZygote.close();
+            Process.killProcess(sZygote.getPid());
+            sZygote = null;
         }
-
-        return WEBVIEW_ZYGOTE_SERVICE_32;
     }
 
     @GuardedBy("sLock")
@@ -198,14 +144,17 @@ public class WebViewZygote {
             return;
         }
 
-        final String serviceName = getServiceNameLocked();
-        if (!SystemService.isRunning(serviceName)) {
-            Log.e(LOGTAG, serviceName + " is not running");
-            return;
-        }
-
         try {
-            sZygote = new ZygoteProcess(WEBVIEW_ZYGOTE_SOCKET, null);
+            sZygote = Process.zygoteProcess.startChildZygote(
+                    "com.android.internal.os.WebViewZygoteInit",
+                    "webview_zygote",
+                    Process.WEBVIEW_ZYGOTE_UID,
+                    Process.WEBVIEW_ZYGOTE_UID,
+                    null,  // gids
+                    0,  // runtimeFlags
+                    "webview_zygote",  // seInfo
+                    sPackage.applicationInfo.primaryCpuAbi,  // abi
+                    null);  // instructionSet
 
             // 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
@@ -227,14 +176,14 @@ public class WebViewZygote {
             final String cacheKey = (zipPaths.size() == 1) ? zipPaths.get(0) :
                     TextUtils.join(File.pathSeparator, zipPaths);
 
-            ZygoteProcess.waitForConnectionToZygote(WEBVIEW_ZYGOTE_SOCKET);
+            ZygoteProcess.waitForConnectionToZygote(sZygote.getPrimarySocketAddress());
 
             Log.d(LOGTAG, "Preloading package " + zip + " " + librarySearchPath);
             sZygote.preloadPackageForAbi(zip, librarySearchPath, cacheKey,
                                          Build.SUPPORTED_ABIS[0]);
         } catch (Exception e) {
-            Log.e(LOGTAG, "Error connecting to " + serviceName, e);
+            Log.e(LOGTAG, "Error connecting to webview zygote", e);
-            sZygote = null;
+            stopZygoteLocked();
         }
     }
 }

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

@@ -18,9 +18,11 @@ package com.android.internal.os;
 
 import android.app.ApplicationLoaders;
 import android.net.LocalSocket;
+import android.net.LocalServerSocket;
 import android.os.Build;
 import android.system.ErrnoException;
 import android.system.Os;
+import android.system.OsConstants;
 import android.text.TextUtils;
 import android.util.Log;
 import android.webkit.WebViewFactory;
@@ -118,18 +120,35 @@ class WebViewZygoteInit {
     }
 
     public static void main(String argv[]) {
-        sServer = new WebViewZygoteServer();
+        Log.i(TAG, "Starting WebViewZygoteInit");
 
-        // Zygote goes into its own process group.
+        String socketName = null;
-        try {
+        for (String arg : argv) {
-            Os.setpgid(0, 0);
+            Log.i(TAG, arg);
-        } catch (ErrnoException ex) {
+            if (arg.startsWith(Zygote.CHILD_ZYGOTE_SOCKET_NAME_ARG)) {
-            throw new RuntimeException("Failed to setpgid(0,0)", ex);
+                socketName = arg.substring(Zygote.CHILD_ZYGOTE_SOCKET_NAME_ARG.length());
+            }
         }
+        if (socketName == null) {
+            throw new RuntimeException("No " + Zygote.CHILD_ZYGOTE_SOCKET_NAME_ARG + " specified");
+        }
+
+        try {
+            Os.prctl(OsConstants.PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0);
+        } catch (ErrnoException ex) {
+            throw new RuntimeException("Failed to set PR_SET_NO_NEW_PRIVS", ex);
+        }
+
+        sServer = new WebViewZygoteServer();
 
         final Runnable caller;
         try {
-            sServer.registerServerSocketFromEnv("webview_zygote");
+            sServer.registerServerSocketAtAbstractName(socketName);
+
+            // Add the abstract socket to the FD whitelist so that the native zygote code
+            // can properly detach it after forking.
+            Zygote.nativeAllowFileAcrossFork("ABSTRACT/" + socketName);
+
             // 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));