Move some system services to separate directories

Refactored the directory structure so that services can be optionally
excluded. This is step 1. Will be followed by another change that makes
it possible to remove services from the build.

Change-Id: Ideacedfd34b5e213217ad3ff4ebb21c4a8e73f85

1 files changed, 483 insertions, 0 deletions

diff --git a/services/core/java/com/android/server/Watchdog.java b/services/core/java/com/android/server/Watchdog.java
new file mode 100644
index 0000000..b249953
--- /dev/null
+++ b/services/core/java/com/android/server/Watchdog.java
@@ -0,0 +1,483 @@
+/*
+ * Copyright (C) 2008 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 com.android.server;
+
+import android.app.IActivityController;
+import android.os.Binder;
+import android.os.RemoteException;
+import com.android.server.am.ActivityManagerService;
+import com.android.server.power.PowerManagerService;
+
+import android.app.AlarmManager;
+import android.app.PendingIntent;
+import android.content.BroadcastReceiver;
+import android.content.ContentResolver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.os.BatteryManager;
+import android.os.Debug;
+import android.os.Handler;
+import android.os.Looper;
+import android.os.Process;
+import android.os.ServiceManager;
+import android.os.SystemClock;
+import android.os.SystemProperties;
+import android.util.EventLog;
+import android.util.Log;
+import android.util.Slog;
+
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Calendar;
+
+/** This class calls its monitor every minute. Killing this process if they don't return **/
+public class Watchdog extends Thread {
+    static final String TAG = "Watchdog";
+    static final boolean localLOGV = false || false;
+
+    // Set this to true to use debug default values.
+    static final boolean DB = false;
+
+    // Set this to true to have the watchdog record kernel thread stacks when it fires
+    static final boolean RECORD_KERNEL_THREADS = true;
+
+    static final long DEFAULT_TIMEOUT = DB ? 10*1000 : 60*1000;
+    static final long CHECK_INTERVAL = DEFAULT_TIMEOUT / 2;
+
+    // These are temporally ordered: larger values as lateness increases
+    static final int COMPLETED = 0;
+    static final int WAITING = 1;
+    static final int WAITED_HALF = 2;
+    static final int OVERDUE = 3;
+
+    // Which native processes to dump into dropbox's stack traces
+    public static final String[] NATIVE_STACKS_OF_INTEREST = new String[] {
+        "/system/bin/mediaserver",
+        "/system/bin/sdcard",
+        "/system/bin/surfaceflinger"
+    };
+
+    static Watchdog sWatchdog;
+
+    /* This handler will be used to post message back onto the main thread */
+    final ArrayList<HandlerChecker> mHandlerCheckers = new ArrayList<HandlerChecker>();
+    final HandlerChecker mMonitorChecker;
+    ContentResolver mResolver;
+    ActivityManagerService mActivity;
+
+    int mPhonePid;
+    IActivityController mController;
+    boolean mAllowRestart = true;
+
+    /**
+     * Used for checking status of handle threads and scheduling monitor callbacks.
+     */
+    public final class HandlerChecker implements Runnable {
+        private final Handler mHandler;
+        private final String mName;
+        private final long mWaitMax;
+        private final ArrayList<Monitor> mMonitors = new ArrayList<Monitor>();
+        private boolean mCompleted;
+        private Monitor mCurrentMonitor;
+        private long mStartTime;
+
+        HandlerChecker(Handler handler, String name, long waitMaxMillis) {
+            mHandler = handler;
+            mName = name;
+            mWaitMax = waitMaxMillis;
+            mCompleted = true;
+        }
+
+        public void addMonitor(Monitor monitor) {
+            mMonitors.add(monitor);
+        }
+
+        public void scheduleCheckLocked() {
+            if (mMonitors.size() == 0 && mHandler.getLooper().isIdling()) {
+                // If the target looper is or just recently was idling, then
+                // there is no reason to enqueue our checker on it since that
+                // is as good as it not being deadlocked.  This avoid having
+                // to do a context switch to check the thread.  Note that we
+                // only do this if mCheckReboot is false and we have no
+                // monitors, since those would need to be executed at this point.
+                mCompleted = true;
+                return;
+            }
+
+            if (!mCompleted) {
+                // we already have a check in flight, so no need
+                return;
+            }
+
+            mCompleted = false;
+            mCurrentMonitor = null;
+            mStartTime = SystemClock.uptimeMillis();
+            mHandler.postAtFrontOfQueue(this);
+        }
+
+        public boolean isOverdueLocked() {
+            return (!mCompleted) && (SystemClock.uptimeMillis() > mStartTime + mWaitMax);
+        }
+
+        public int getCompletionStateLocked() {
+            if (mCompleted) {
+                return COMPLETED;
+            } else {
+                long latency = SystemClock.uptimeMillis() - mStartTime;
+                if (latency < mWaitMax/2) {
+                    return WAITING;
+                } else if (latency < mWaitMax) {
+                    return WAITED_HALF;
+                }
+            }
+            return OVERDUE;
+        }
+
+        public Thread getThread() {
+            return mHandler.getLooper().getThread();
+        }
+
+        public String getName() {
+            return mName;
+        }
+
+        public String describeBlockedStateLocked() {
+            if (mCurrentMonitor == null) {
+                return "Blocked in handler on " + mName + " (" + getThread().getName() + ")";
+            } else {
+                return "Blocked in monitor " + mCurrentMonitor.getClass().getName()
+                        + " on " + mName + " (" + getThread().getName() + ")";
+            }
+        }
+
+        @Override
+        public void run() {
+            final int size = mMonitors.size();
+            for (int i = 0 ; i < size ; i++) {
+                synchronized (Watchdog.this) {
+                    mCurrentMonitor = mMonitors.get(i);
+                }
+                mCurrentMonitor.monitor();
+            }
+
+            synchronized (Watchdog.this) {
+                mCompleted = true;
+                mCurrentMonitor = null;
+            }
+        }
+    }
+
+    final class RebootRequestReceiver extends BroadcastReceiver {
+        @Override
+        public void onReceive(Context c, Intent intent) {
+            if (intent.getIntExtra("nowait", 0) != 0) {
+                rebootSystem("Received ACTION_REBOOT broadcast");
+                return;
+            }
+            Slog.w(TAG, "Unsupported ACTION_REBOOT broadcast: " + intent);
+        }
+    }
+
+    public interface Monitor {
+        void monitor();
+    }
+
+    public static Watchdog getInstance() {
+        if (sWatchdog == null) {
+            sWatchdog = new Watchdog();
+        }
+
+        return sWatchdog;
+    }
+
+    private Watchdog() {
+        super("watchdog");
+        // Initialize handler checkers for each common thread we want to check.  Note
+        // that we are not currently checking the background thread, since it can
+        // potentially hold longer running operations with no guarantees about the timeliness
+        // of operations there.
+
+        // The shared foreground thread is the main checker.  It is where we
+        // will also dispatch monitor checks and do other work.
+        mMonitorChecker = new HandlerChecker(FgThread.getHandler(),
+                "foreground thread", DEFAULT_TIMEOUT);
+        mHandlerCheckers.add(mMonitorChecker);
+        // Add checker for main thread.  We only do a quick check since there
+        // can be UI running on the thread.
+        mHandlerCheckers.add(new HandlerChecker(new Handler(Looper.getMainLooper()),
+                "main thread", DEFAULT_TIMEOUT));
+        // Add checker for shared UI thread.
+        mHandlerCheckers.add(new HandlerChecker(UiThread.getHandler(),
+                "ui thread", DEFAULT_TIMEOUT));
+        // And also check IO thread.
+        mHandlerCheckers.add(new HandlerChecker(IoThread.getHandler(),
+                "i/o thread", DEFAULT_TIMEOUT));
+    }
+
+    public void init(Context context, ActivityManagerService activity) {
+        mResolver = context.getContentResolver();
+        mActivity = activity;
+
+        context.registerReceiver(new RebootRequestReceiver(),
+                new IntentFilter(Intent.ACTION_REBOOT),
+                android.Manifest.permission.REBOOT, null);
+    }
+
+    public void processStarted(String name, int pid) {
+        synchronized (this) {
+            if ("com.android.phone".equals(name)) {
+                mPhonePid = pid;
+            }
+        }
+    }
+
+    public void setActivityController(IActivityController controller) {
+        synchronized (this) {
+            mController = controller;
+        }
+    }
+
+    public void setAllowRestart(boolean allowRestart) {
+        synchronized (this) {
+            mAllowRestart = allowRestart;
+        }
+    }
+
+    public void addMonitor(Monitor monitor) {
+        synchronized (this) {
+            if (isAlive()) {
+                throw new RuntimeException("Monitors can't be added once the Watchdog is running");
+            }
+            mMonitorChecker.addMonitor(monitor);
+        }
+    }
+
+    public void addThread(Handler thread, String name) {
+        addThread(thread, name, DEFAULT_TIMEOUT);
+    }
+
+    public void addThread(Handler thread, String name, long timeoutMillis) {
+        synchronized (this) {
+            if (isAlive()) {
+                throw new RuntimeException("Threads can't be added once the Watchdog is running");
+            }
+            mHandlerCheckers.add(new HandlerChecker(thread, name, timeoutMillis));
+        }
+    }
+
+    /**
+     * Perform a full reboot of the system.
+     */
+    void rebootSystem(String reason) {
+        Slog.i(TAG, "Rebooting system because: " + reason);
+        PowerManagerService pms = (PowerManagerService) ServiceManager.getService("power");
+        pms.reboot(false, reason, false);
+    }
+
+    private int evaluateCheckerCompletionLocked() {
+        int state = COMPLETED;
+        for (int i=0; i<mHandlerCheckers.size(); i++) {
+            HandlerChecker hc = mHandlerCheckers.get(i);
+            state = Math.max(state, hc.getCompletionStateLocked());
+        }
+        return state;
+    }
+
+    private ArrayList<HandlerChecker> getBlockedCheckersLocked() {
+        ArrayList<HandlerChecker> checkers = new ArrayList<HandlerChecker>();
+        for (int i=0; i<mHandlerCheckers.size(); i++) {
+            HandlerChecker hc = mHandlerCheckers.get(i);
+            if (hc.isOverdueLocked()) {
+                checkers.add(hc);
+            }
+        }
+        return checkers;
+    }
+
+    private String describeCheckersLocked(ArrayList<HandlerChecker> checkers) {
+        StringBuilder builder = new StringBuilder(128);
+        for (int i=0; i<checkers.size(); i++) {
+            if (builder.length() > 0) {
+                builder.append(", ");
+            }
+            builder.append(checkers.get(i).describeBlockedStateLocked());
+        }
+        return builder.toString();
+    }
+
+    @Override
+    public void run() {
+        boolean waitedHalf = false;
+        while (true) {
+            final ArrayList<HandlerChecker> blockedCheckers;
+            final String subject;
+            final boolean allowRestart;
+            synchronized (this) {
+                long timeout = CHECK_INTERVAL;
+                // Make sure we (re)spin the checkers that have become idle within
+                // this wait-and-check interval
+                for (int i=0; i<mHandlerCheckers.size(); i++) {
+                    HandlerChecker hc = mHandlerCheckers.get(i);
+                    hc.scheduleCheckLocked();
+                }
+
+                // NOTE: We use uptimeMillis() here because we do not want to increment the time we
+                // wait while asleep. If the device is asleep then the thing that we are waiting
+                // to timeout on is asleep as well and won't have a chance to run, causing a false
+                // positive on when to kill things.
+                long start = SystemClock.uptimeMillis();
+                while (timeout > 0) {
+                    try {
+                        wait(timeout);
+                    } catch (InterruptedException e) {
+                        Log.wtf(TAG, e);
+                    }
+                    timeout = CHECK_INTERVAL - (SystemClock.uptimeMillis() - start);
+                }
+
+                final int waitState = evaluateCheckerCompletionLocked();
+                if (waitState == COMPLETED) {
+                    // The monitors have returned; reset
+                    waitedHalf = false;
+                    continue;
+                } else if (waitState == WAITING) {
+                    // still waiting but within their configured intervals; back off and recheck
+                    continue;
+                } else if (waitState == WAITED_HALF) {
+                    if (!waitedHalf) {
+                        // We've waited half the deadlock-detection interval.  Pull a stack
+                        // trace and wait another half.
+                        ArrayList<Integer> pids = new ArrayList<Integer>();
+                        pids.add(Process.myPid());
+                        ActivityManagerService.dumpStackTraces(true, pids, null, null,
+                                NATIVE_STACKS_OF_INTEREST);
+                        waitedHalf = true;
+                    }
+                    continue;
+                }
+
+                // something is overdue!
+                blockedCheckers = getBlockedCheckersLocked();
+                subject = describeCheckersLocked(blockedCheckers);
+                allowRestart = mAllowRestart;
+            }
+
+            // If we got here, that means that the system is most likely hung.
+            // First collect stack traces from all threads of the system process.
+            // Then kill this process so that the system will restart.
+            EventLog.writeEvent(EventLogTags.WATCHDOG, subject);
+
+            ArrayList<Integer> pids = new ArrayList<Integer>();
+            pids.add(Process.myPid());
+            if (mPhonePid > 0) pids.add(mPhonePid);
+            // Pass !waitedHalf so that just in case we somehow wind up here without having
+            // dumped the halfway stacks, we properly re-initialize the trace file.
+            final File stack = ActivityManagerService.dumpStackTraces(
+                    !waitedHalf, pids, null, null, NATIVE_STACKS_OF_INTEREST);
+
+            // Give some extra time to make sure the stack traces get written.
+            // The system's been hanging for a minute, another second or two won't hurt much.
+            SystemClock.sleep(2000);
+
+            // Pull our own kernel thread stacks as well if we're configured for that
+            if (RECORD_KERNEL_THREADS) {
+                dumpKernelStackTraces();
+            }
+
+            // Trigger the kernel to dump all blocked threads to the kernel log
+            try {
+                FileWriter sysrq_trigger = new FileWriter("/proc/sysrq-trigger");
+                sysrq_trigger.write("w");
+                sysrq_trigger.close();
+            } catch (IOException e) {
+                Slog.e(TAG, "Failed to write to /proc/sysrq-trigger");
+                Slog.e(TAG, e.getMessage());
+            }
+
+            // Try to add the error to the dropbox, but assuming that the ActivityManager
+            // itself may be deadlocked.  (which has happened, causing this statement to
+            // deadlock and the watchdog as a whole to be ineffective)
+            Thread dropboxThread = new Thread("watchdogWriteToDropbox") {
+                    public void run() {
+                        mActivity.addErrorToDropBox(
+                                "watchdog", null, "system_server", null, null,
+                                subject, null, stack, null);
+                    }
+                };
+            dropboxThread.start();
+            try {
+                dropboxThread.join(2000);  // wait up to 2 seconds for it to return.
+            } catch (InterruptedException ignored) {}
+
+            IActivityController controller;
+            synchronized (this) {
+                controller = mController;
+            }
+            if (controller != null) {
+                Slog.i(TAG, "Reporting stuck state to activity controller");
+                try {
+                    Binder.setDumpDisabled("Service dumps disabled due to hung system process.");
+                    // 1 = keep waiting, -1 = kill system
+                    int res = controller.systemNotResponding(subject);
+                    if (res >= 0) {
+                        Slog.i(TAG, "Activity controller requested to coninue to wait");
+                        waitedHalf = false;
+                        continue;
+                    }
+                } catch (RemoteException e) {
+                }
+            }
+
+            // Only kill the process if the debugger is not attached.
+            if (Debug.isDebuggerConnected()) {
+                Slog.w(TAG, "Debugger connected: Watchdog is *not* killing the system process");
+            } else if (!allowRestart) {
+                Slog.w(TAG, "Restart not allowed: Watchdog is *not* killing the system process");
+            } else {
+                Slog.w(TAG, "*** WATCHDOG KILLING SYSTEM PROCESS: " + subject);
+                for (int i=0; i<blockedCheckers.size(); i++) {
+                    Slog.w(TAG, blockedCheckers.get(i).getName() + " stack trace:");
+                    StackTraceElement[] stackTrace
+                            = blockedCheckers.get(i).getThread().getStackTrace();
+                    for (StackTraceElement element: stackTrace) {
+                        Slog.w(TAG, "    at " + element);
+                    }
+                }
+                Slog.w(TAG, "*** GOODBYE!");
+                Process.killProcess(Process.myPid());
+                System.exit(10);
+            }
+
+            waitedHalf = false;
+        }
+    }
+
+    private File dumpKernelStackTraces() {
+        String tracesPath = SystemProperties.get("dalvik.vm.stack-trace-file", null);
+        if (tracesPath == null || tracesPath.length() == 0) {
+            return null;
+        }
+
+        native_dumpKernelStacks(tracesPath);
+        return new File(tracesPath);
+    }
+
+    private native void native_dumpKernelStacks(String tracesPath);
+}