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Bug 351269

Summary:	Display#asyncExec causes deadlock
Product:	[RT] RAP	Reporter:	maoxuepeng <maoxuepeng>
Component:	RWT	Assignee:	Project Inbox <rap-inbox>
Status:	RESOLVED WORKSFORME	QA Contact:
Severity:	major
Priority:	P3
Version:	1.3
Target Milestone:	---
Hardware:	All
OS:	All
Whiteboard:

Description maoxuepeng

2011-07-06 02:54:24 EDT

Build Identifier: 20090619-0625

when we call the Display.asyncExec a little more frequently, then, the thread who call Display.asyncExec and the UIThread were dead locked.

stack info-------------------------
Found one Java-level deadlock:
=============================
"UIThread [1318389028214@180F4F39B29FFC8C43A72AE025367F56]":
  waiting to lock monitor 0x00002aaabd515d10 (object 0x00002aaab138d008, a java.lang.Object),
  which is held by "pool-5-thread-12"
"pool-5-thread-12":
  waiting to lock monitor 0x00002aaac0b8d1e0 (object 0x00002aaab27c2168, a java.lang.Object),
  which is held by "UIThread [1318342863314@0EB611216119E381C23A320412CA3939]"
"UIThread [1318342863314@0EB611216119E381C23A320412CA3939]":
  waiting to lock monitor 0x00002aaabd43db40 (object 0x00002aaab27b8930, a java.lang.Object),
  which is held by "pool-5-thread-12"


"pool-5-thread-12":
	at org.eclipse.rwt.internal.lifecycle.UICallBackManager.sendUICallBack(UICallBackManager.java:69)
	- waiting to lock <0x00002aaab27c2168> (a java.lang.Object)
	at org.eclipse.swt.widgets.Display$2.run(Display.java:1161)
	at org.eclipse.rwt.internal.lifecycle.FakeContextUtil.runNonUIThreadWithFakeContext(FakeContextUtil.java:60)
	at org.eclipse.rwt.lifecycle.UICallBack.runNonUIThreadWithFakeContext(UICallBack.java:48)
	at org.eclipse.swt.widgets.Display.wakeThread(Display.java:1159)
	at org.eclipse.swt.widgets.Synchronizer.addLast(Synchronizer.java:73)
	at org.eclipse.swt.widgets.Synchronizer.asyncExec(Synchronizer.java:95)
	at org.eclipse.ui.internal.UISynchronizer.asyncExec(UISynchronizer.java:129)
	at org.eclipse.swt.widgets.Display.asyncExec(Display.java:984)
	- locked <0x00002aaab27b8930> (a java.lang.Object)
	at imap.vts.osmu.maint.ui.BoardListComposite$BoardIPNetMaskListener.stateChanged(BoardListComposite.java:951)
	at imap.vts.osmu.svc.impl.boardstate.ServerContextMgr.notifyIPAndNetmaskChangedListeners(ServerContextMgr.java:885)
	- locked <0x00002aaab138d008> (a java.lang.Object)
	at imap.vts.osmu.svc.impl.boardstate.device.DeviceStateBase.notifyIPAndNetmaskChangedListeners(DeviceStateBase.java:135)
	at imap.vts.osmu.svc.impl.boardstate.device.DeviceStateBase.notifyListeners(DeviceStateBase.java:118)
	- locked <0x00002aaab1b99130> (a java.lang.Object)
	at imap.vts.osmu.svc.impl.boardstate.device.DeviceStateBase.resetStateContext(DeviceStateBase.java:92)
	at imap.vts.osmu.svc.impl.boardstate.MultiQueryState$1.executeDetailHandler(MultiQueryState.java:36)
	at imap.vts.osmu.common.threadpool.DataHandleThread.call(DataHandleThread.java:83)
	at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
	at java.util.concurrent.FutureTask.run(FutureTask.java:138)
	at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
	at java.lang.Thread.run(Thread.java:619)
"UIThread [1318342863314@0EB611216119E381C23A320412CA3939]":
	at org.eclipse.swt.graphics.Device.isDisposed(Device.java:300)
	- waiting to lock <0x00002aaab27b8930> (a java.lang.Object)
	at org.eclipse.rwt.internal.lifecycle.UICallBackManager.hasRunnables(UICallBackManager.java:100)
	at org.eclipse.rwt.internal.lifecycle.UICallBackManager.notifyUIThreadEnd(UICallBackManager.java:91)
	- locked <0x00002aaab27c2168> (a java.lang.Object)
	at org.eclipse.rwt.internal.lifecycle.RWTLifeCycle.sleep(RWTLifeCycle.java:297)
	at org.eclipse.swt.widgets.Display.sleep(Display.java:1128)
	at org.eclipse.ui.application.WorkbenchAdvisor.eventLoopIdle(WorkbenchAdvisor.java:361)
	at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2391)
	at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2351)
	at org.eclipse.ui.internal.Workbench.access$5(Workbench.java:2206)
	at org.eclipse.ui.internal.Workbench$4.run(Workbench.java:424)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
	at org.eclipse.jface.internal.databinding.realmadapter.RealmAdapter.run(RealmAdapter.java:44)
	at org.eclipse.rap.ui.internal.RealmAdapterHook.runWithDefault(RealmAdapterHook.java:48)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:427)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:157)
	at imap.vts.ui.internal.RapApplication.createUI(RapApplication.java:81)
	at org.eclipse.rwt.internal.lifecycle.EntryPointManager.createUI(EntryPointManager.java:92)
	at org.eclipse.rwt.internal.lifecycle.RWTLifeCycle.createUI(RWTLifeCycle.java:245)
	at org.eclipse.rwt.internal.lifecycle.RWTLifeCycle$UIThreadController.run(RWTLifeCycle.java:114)
	- locked <0x00002aaab2721328> (a org.eclipse.rwt.internal.lifecycle.UIThread)
	at java.lang.Thread.run(Thread.java:619)
	at org.eclipse.rwt.internal.lifecycle.UIThread.run(UIThread.java:102)

-------------------------------

it is easy to reproduce, is there any workround about it?

Reproducible: Sometimes

Steps to Reproduce:
1. In an object that hold a collection of listeners.
2. Start a backround thered every seconds, e.g 30s, notify the listeners.
3. In the listeners, call Display.asyncExec(new Runnable()...).
4. Open many browser, after a few minuts, it maybe dead locked.

Comment 1 Ralf Sternberg

2011-07-10 04:58:11 EDT

Could you try to reproduce this issue with RAP 1.4? There are no further builds planned for 1.3, so if we can only repair it in 1.4 if the issue still exists there.
Thanks.

Comment 2 Ralf Sternberg

2011-12-22 09:10:16 EST

Resolving this issue as it has been reported for 1.3 and there is no indication that is is present also in 1.4+.
Please reopen if you can reproduce it with RAP 1.4 or later.