Dianne Hackborn 8d044e8bc2 Start combining threads in system process.
This introduces four generic thread that services can
use in the system process:

- Background: part of the framework for all processes, for
work that is purely background (no timing constraint).
- UI: for time-critical display of UI.
- Foreground: normal foreground work.
- IO: performing IO operations.

I went through and moved services into these threads in the
places I felt relatively comfortable about understanding what
they are doing.  There are still a bunch more we need to look
at -- lots of networking stuff left, 3 or so different native
daemon connectors which I didn't know how much would block,
audio stuff, etc.

Also updated Watchdog to be aware of and check these new
threads, with a new API for other threads to also participate
in this checking.

Change-Id: Ie2f11061cebde5f018d7383b3a910fbbd11d5e11
2013-05-02 17:42:40 -07:00

72 lines
2.3 KiB
Java

/*
* Copyright (C) 2013 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.os.Handler;
import android.os.HandlerThread;
import android.os.StrictMode;
import android.util.Slog;
/**
* Shared singleton thread for showing UI. This is a foreground thread, and in
* additional should not have operations that can take more than a few ms scheduled
* on it to avoid UI jank.
*/
public final class UiThread extends HandlerThread {
private static UiThread sInstance;
private static Handler sHandler;
private UiThread() {
super("android.ui", android.os.Process.THREAD_PRIORITY_FOREGROUND);
}
private static void ensureThreadLocked() {
if (sInstance == null) {
sInstance = new UiThread();
sInstance.start();
sHandler = new Handler(sInstance.getLooper());
sHandler.post(new Runnable() {
@Override
public void run() {
//Looper.myLooper().setMessageLogging(new LogPrinter(
// Log.VERBOSE, "WindowManagerPolicy", Log.LOG_ID_SYSTEM));
android.os.Process.setCanSelfBackground(false);
// For debug builds, log event loop stalls to dropbox for analysis.
if (StrictMode.conditionallyEnableDebugLogging()) {
Slog.i("UiThread", "Enabled StrictMode logging for UI thread");
}
}
});
}
}
public static UiThread get() {
synchronized (UiThread.class) {
ensureThreadLocked();
return sInstance;
}
}
public static Handler getHandler() {
synchronized (UiThread.class) {
ensureThreadLocked();
return sHandler;
}
}
}