Revert "Watchdog: Improvement of debuggability"

This reverts commit 9211b13.

Author: Jean-Baptiste Queru

services/java/com/android/server/Watchdog.java

@@ -25,7 +25,6 @@
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
-import android.os.Build;
 import android.os.Debug;
 import android.os.Handler;
 import android.os.Message;
@@ -39,8 +38,6 @@
 import android.util.Slog;
 
 import java.io.File;
-import java.io.FileWriter;
-import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Calendar;
 
@@ -431,10 +428,11 @@ public void run() {
             }
 
             // 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.
 
             final String name = (mCurrentMonitor != null) ?
                     mCurrentMonitor.getClass().getName() : "null";
-            Slog.w(TAG, "WATCHDOG PROBLEM IN SYSTEM SERVER: " + name);
             EventLog.writeEvent(EventLogTags.WATCHDOG, name);
 
             ArrayList<Integer> pids = new ArrayList<Integer>();
@@ -469,15 +467,11 @@ public void run() {
                 dropboxThread.join(2000);  // wait up to 2 seconds for it to return.
             } catch (InterruptedException ignored) {}
 
-            // Only kill/crash the process if the debugger is not attached.
+            // Only kill the process if the debugger is not attached.
             if (!Debug.isDebuggerConnected()) {
                 Slog.w(TAG, "*** WATCHDOG KILLING SYSTEM PROCESS: " + name);
-                if (!Build.TYPE.equals("user")) {
-                    forceCrashDump();
-                } else {
-                    Process.killProcess(Process.myPid());
-                    System.exit(10);
-                }
+                Process.killProcess(Process.myPid());
+                System.exit(10);
             } else {
                 Slog.w(TAG, "Debugger connected: Watchdog is *not* killing the system process");
             }
@@ -486,50 +480,6 @@ public void run() {
         }
     }
 
-    private void forceCrashDump() {
-        /* Sync file system to flash the data which is written just before the
-         * crash.
-         */
-        java.lang.Process p = null;
-        try {
-            p = Runtime.getRuntime().exec("sync");
-            if (p != null) {
-                // It is not necessary to check the exit code, here.
-                // 'sync' command always succeeds, and this function returns 0.
-                p.waitFor();
-            } else {
-                Slog.e(TAG, "Failed to execute 'sync' command. (no process handle)");
-            }
-        } catch (Exception e) {
-            // This code is an emergency path to crash MUT. The system already
-            // caused fatal error, and then calls this function to create a
-            // crash dump. This function must run the code below to force a
-            // crash, even if the sync command failed.
-            // Therefore, ignore all exceptions, here.
-            Slog.e(TAG, "Failed to execute 'sync' command prior to forcing crash: " + e);
-        } finally {
-            if (p != null) {
-                p.destroy();
-            }
-        }
-
-        FileWriter out = null;
-        try {
-            out = new FileWriter("/proc/sysrq-trigger");
-            out.write("c");
-        } catch (IOException e) {
-            Slog.e(TAG, "Failed to write to sysrq-trigger while triggering crash: " + e);
-        } finally {
-            if (out != null) {
-                try {
-                    out.close();
-                } catch (IOException e) {
-                    Slog.e(TAG, "Failed to close sysrq-trigger while triggering crash: " + e);
-                }
-            }
-        }
-    }
-
     private File dumpKernelStackTraces() {
         String tracesPath = SystemProperties.get("dalvik.vm.stack-trace-file", null);
         if (tracesPath == null || tracesPath.length() == 0) {