[news.eclipse.modeling.tmf] Re: Potential for deadlock in DefaultScopePr

[Sven Efftinge <sven.efftinge@xxxxxxxxx>]

Hi Miles,

thanks for the information.
Unfortunately I wasn't able to reproduce it (damn concurrency issues...)

I've filed a bugzilla so we can have a more cloer look as soon as it 
occurs a second time or we find a way to reproduce it.

https://bugs.eclipse.org/bugs/show_bug.cgi?id=289553

Cheers,
Sven

Miles Parker schrieb:
> Hi guys,
>
> I wanted to mention a deadlock situation that I came across. I'm not 
> sure yet if it's something completely silly that I've done that wouldn't 
> show up in a normal use case, but here are the stacks. The issue seems 
> to be in the case where there are two singleton scope providers, one of 
> which refers to the other. I think I can solve the issue for my usage 
> but I thought I'd point it out for when you are looking at the 
> SimpleCache implementation again -- I see you have a TODO mark there.
>
> cheers,
>
> Miles
>
>
> Worker-16 [BLOCKED; waiting to lock 
> org.eclipse.xtext.util.SimpleCache@4ebe2938]
> org.eclipse.xtext.util.SimpleCache.get(SimpleCache.java)
> org.eclipse.xtext.scoping.impl.DefaultScopeProvider.getScope(DefaultScopeProvider.java:79) 
>
> org.eclipse.amp.amf.parameters.scoping.AParScopeProvider.getScope(AParScopeProvider.java:65) 
>
> org.eclipse.xtext.linking.impl.DefaultLinkingService.getScope(DefaultLinkingService.java:55) 
>
> org.eclipse.xtext.linking.impl.DefaultLinkingService.getLinkedObjects(DefaultLinkingService.java:66) 
>
> org.eclipse.xtext.linking.impl.Linker.getLinkedObject(Linker.java:145)
> org.eclipse.xtext.linking.impl.Linker.ensureIsLinked(Linker.java:102)
> org.eclipse.xtext.linking.impl.Linker.ensureLinked(Linker.java:55)
> org.eclipse.xtext.linking.impl.Linker.ensureModelLinked(Linker.java:170)
> org.eclipse.xtext.linking.impl.Linker.doLinkModel(Linker.java:163)
> org.eclipse.xtext.linking.impl.AbstractCleaningLinker.linkModel(AbstractCleaningLinker.java:24) 
>
> org.eclipse.xtext.resource.XtextResource.doLinking(XtextResource.java:140)
> org.eclipse.xtext.linking.lazy.LazyLinkingResource.doLinking(LazyLinkingResource.java:50) 
>
> org.eclipse.xtext.resource.XtextResource.doLoad(XtextResource.java:160)
> org.eclipse.xtext.linking.lazy.LazyLinkingResource.doLoad(LazyLinkingResource.java:43) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceImpl.load(ResourceImpl.java:1494) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceImpl.load(ResourceImpl.java:1282) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.demandLoad(ResourceSetImpl.java:255) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.demandLoadHelper(ResourceSetImpl.java:270) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.getResource(ResourceSetImpl.java:397) 
>
> org.eclipse.xtext.scoping.impl.ImportUriUtil.getResource(ImportUriUtil.java:54) 
>
> org.eclipse.xtext.scoping.impl.DefaultScope$LazyReferencedResourceScope.<init>(DefaultScope.java:58) 
>
> org.eclipse.xtext.scoping.impl.DefaultScope.createParent(DefaultScope.java:50) 
>
> org.eclipse.xtext.scoping.impl.DefaultScope.<init>(DefaultScope.java:34)
> org.eclipse.xtext.scoping.impl.DefaultScope.<init>(DefaultScope.java:30)
> org.eclipse.xtext.scoping.impl.DefaultScopeProvider.createScope(DefaultScopeProvider.java:72) 
>
> org.eclipse.xtext.scoping.impl.DefaultScopeProvider$2.apply(DefaultScopeProvider.java:67) 
>
> org.eclipse.xtext.scoping.impl.DefaultScopeProvider$2.apply(DefaultScopeProvider.java:1) 
>
> org.eclipse.xtext.util.SimpleCache.get(SimpleCache.java:33)
> org.eclipse.xtext.scoping.impl.DefaultScopeProvider.getScope(DefaultScopeProvider.java:79) 
>
> org.eclipse.amp.amf.parameters.scoping.AParScopeProvider.getScope(AParScopeProvider.java:65) 
>
> org.eclipse.amp.amf.testing.scoping.ATestScopeProvider.getScope(ATestScopeProvider.java:46) 
>
> org.eclipse.xtext.linking.impl.DefaultLinkingService.getScope(DefaultLinkingService.java:55) 
>
> org.eclipse.xtext.linking.impl.DefaultLinkingService.getLinkedObjects(DefaultLinkingService.java:66) 
>
> org.eclipse.xtext.linking.impl.Linker.getLinkedObject(Linker.java:145)
> org.eclipse.xtext.linking.impl.Linker.ensureIsLinked(Linker.java:102)
> org.eclipse.xtext.linking.impl.Linker.ensureLinked(Linker.java:55)
> org.eclipse.xtext.linking.impl.Linker.ensureModelLinked(Linker.java:170)
> org.eclipse.xtext.linking.impl.Linker.doLinkModel(Linker.java:163)
> org.eclipse.xtext.linking.impl.AbstractCleaningLinker.linkModel(AbstractCleaningLinker.java:24) 
>
> org.eclipse.xtext.resource.XtextResource.doLinking(XtextResource.java:140)
> org.eclipse.xtext.linking.lazy.LazyLinkingResource.doLinking(LazyLinkingResource.java:50) 
>
> org.eclipse.xtext.resource.XtextResource.doLoad(XtextResource.java:160)
> org.eclipse.xtext.linking.lazy.LazyLinkingResource.doLoad(LazyLinkingResource.java:43) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceImpl.load(ResourceImpl.java:1494) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceImpl.load(ResourceImpl.java:1282) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.demandLoad(ResourceSetImpl.java:255) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.demandLoadHelper(ResourceSetImpl.java:270) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.getResource(ResourceSetImpl.java:397) 
>
> org.eclipse.amp.amf.testing.ATestInterpreter.load(ATestInterpreter.java:76)
> org.eclipse.amp.amf.testing.ide.TestRun$1.run(TestRun.java:127)
> org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)
>
>
> Worker-25
> [BLOCKED; waiting to lock org.eclipse.xtext.util.SimpleCache@60fc37f6]
> org.eclipse.xtext.util.SimpleCache.isEmpty(SimpleCache.java)
> org.eclipse.xtext.scoping.impl.DefaultScopeProvider$1.notifyChanged(DefaultScopeProvider.java:37) 
>
> org.eclipse.emf.common.notify.impl.BasicNotifierImpl.eNotify(BasicNotifierImpl.java:280) 
>
> org.eclipse.emf.common.notify.impl.NotifyingListImpl.dispatchNotification(NotifyingListImpl.java:267) 
>
> org.eclipse.emf.common.notify.impl.NotifyingListImpl.addUnique(NotifyingListImpl.java:300) 
>
> org.eclipse.emf.common.util.AbstractEList.add(AbstractEList.java:307)
> org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.createResource(ResourceSetImpl.java:426) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.demandCreateResource(ResourceSetImpl.java:239) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.getResource(ResourceSetImpl.java:391) 
>
> org.eclipse.xtext.scoping.impl.ImportUriUtil.getResource(ImportUriUtil.java:54) 
>
> org.eclipse.xtext.scoping.impl.DefaultScope$LazyReferencedResourceScope.<init>(DefaultScope.java:58) 
>
> org.eclipse.xtext.scoping.impl.DefaultScope.createParent(DefaultScope.java:50) 
>
> org.eclipse.xtext.scoping.impl.DefaultScope.<init>(DefaultScope.java:34)
> org.eclipse.xtext.scoping.impl.DefaultScope.<init>(DefaultScope.java:30)
> org.eclipse.xtext.scoping.impl.DefaultScopeProvider.createScope(DefaultScopeProvider.java:72) 
>
> org.eclipse.xtext.scoping.impl.DefaultScopeProvider$2.apply(DefaultScopeProvider.java:67) 
>
> org.eclipse.xtext.scoping.impl.DefaultScopeProvider$2.apply(DefaultScopeProvider.java:1) 
>
> org.eclipse.xtext.util.SimpleCache.get(SimpleCache.java:33)
> org.eclipse.xtext.scoping.impl.DefaultScopeProvider.getScope(DefaultScopeProvider.java:79) 
>
> org.eclipse.amp.amf.parameters.scoping.AParScopeProvider.getScope(AParScopeProvider.java:65) 
>
> org.eclipse.xtext.linking.impl.DefaultLinkingService.getScope(DefaultLinkingService.java:55) 

> org.eclipse.xtext.linking.impl.DefaultLinkingService.getLinkedObjects(DefaultLinkingService.java:66) 
>
> org.eclipse.xtext.linking.impl.Linker.getLinkedObject(Linker.java:145)
> org.eclipse.xtext.linking.impl.Linker.ensureIsLinked(Linker.java:102)
> org.eclipse.xtext.linking.impl.Linker.ensureLinked(Linker.java:55)
> org.eclipse.xtext.linking.impl.Linker.ensureModelLinked(Linker.java:170)
> org.eclipse.xtext.linking.impl.Linker.doLinkModel(Linker.java:163)
> org.eclipse.xtext.linking.impl.AbstractCleaningLinker.linkModel(AbstractCleaningLinker.java:24) 
>
> org.eclipse.xtext.resource.XtextResource.doLinking(XtextResource.java:140)
> org.eclipse.xtext.linking.lazy.LazyLinkingResource.doLinking(LazyLinkingResource.java:50) 
>
> org.eclipse.xtext.resource.XtextResource.doLoad(XtextResource.java:160)
> org.eclipse.xtext.linking.lazy.LazyLinkingResource.doLoad(LazyLinkingResource.java:43) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceImpl.load(ResourceImpl.java:1494) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceImpl.load(ResourceImpl.java:1282) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.demandLoad(ResourceSetImpl.java:255) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.demandLoadHelper(ResourceSetImpl.java:270) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.getResource(ResourceSetImpl.java:397) 
>
> org.eclipse.amp.amf.testing.scoping.ATestScopeProvider.getScope(ATestScopeProvider.java:53) 
>
> org.eclipse.xtext.linking.impl.DefaultLinkingService.getScope(DefaultLinkingService.java:55) 
>
> org.eclipse.xtext.linking.impl.DefaultLinkingService.getLinkedObjects(DefaultLinkingService.java:66) 
>
> org.eclipse.xtext.linking.impl.Linker.getLinkedObject(Linker.java:145)
> org.eclipse.xtext.linking.impl.Linker.ensureIsLinked(Linker.java:102)
> org.eclipse.xtext.linking.impl.Linker.ensureLinked(Linker.java:55)
> org.eclipse.xtext.linking.impl.Linker.ensureModelLinked(Linker.java:170)
> org.eclipse.xtext.linking.impl.Linker.doLinkModel(Linker.java:163)
> org.eclipse.xtext.linking.impl.AbstractCleaningLinker.linkModel(AbstractCleaningLinker.java:24) 
>
> org.eclipse.xtext.resource.XtextResource.doLinking(XtextResource.java:140)
> org.eclipse.xtext.linking.lazy.LazyLinkingResource.doLinking(LazyLinkingResource.java:50) 
>
> org.eclipse.xtext.resource.XtextResource.doLoad(XtextResource.java:160)
> org.eclipse.xtext.linking.lazy.LazyLinkingResource.doLoad(LazyLinkingResource.java:43) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceImpl.load(ResourceImpl.java:1494) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceImpl.load(ResourceImpl.java:1282) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.demandLoad(ResourceSetImpl.java:255) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.demandLoadHelper(ResourceSetImpl.java:270) 
>
> org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.getResource(ResourceSetImpl.java:397) 
>
> org.eclipse.amp.amf.testing.ATestInterpreter.load(ATestInterpreter.java:76)
> org.eclipse.amp.amf.testing.ide.TestRun$1.run(TestRun.java:127)
> org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)


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