[OpenJDK 2D-Dev] [9] Review Request: 8158072 Need a test for JDK-7172749

[Phil Race]

+1

-phil.

On 05/27/2016 12:36 PM, Sergey Bylokhov wrote:
> On 27.05.16 22:17, Phil Race wrote:
>> I suppose this will pass on the various platforms and pipelines since
>> we've only seen the bug reported against xrender ? ....
>
> Long time ago we had the similar issues on other platforms:
> https://bugs.openjdk.java.net/browse/JDK-7112642
>
> So I assume that it should not fail on all configurations(tested 
> ogl/xrender+linux/osx). But I intentionally added more draw operations 
> and didn't restrict the test on Xrender pipeline, on each platform 
> default will be selected and tested.
>
>>
>>  41  * @bug 8158072
>>
>> I think you should also include 7172749 on this line.
>
> updated:
> http://cr.openjdk.java.net/~serb/8158072/webrev.01
>
>> On 05/27/2016 11:47 AM, Sergey Bylokhov wrote:
>>> Hello.
>>> Please review the new test for jdk9.
>>> To me the reason of JDK-7172749 [1] falling was curious. So I decided
>>> to dig into it.
>>>
>>> To reproduce the bug the next sequence is necessary:
>>> Thread A
>>>  - create the surface
>>>  - SG2D is created for the surface
>>>  - SG2D.drawLine is called
>>>  - XRRenderer(Pipe).drawLine is called
>>>  - ========= STOP "THREAD A" for a nanoseconds=========
>>>
>>> Thread B
>>>  - SG2D is created for the surface create in Thread A
>>>  - SG2D.drawLine is called or any other draw operations.
>>>  - The surface is flushed.
>>>
>>> Thread A
>>>  -  ========= RUN "THREAD A" again=========
>>>  - (we still inside XRRenderer(Pipe).drawLine)
>>>  - SG2D.getCompClip() is called, and this caused revalidation of SG2D,
>>> because it was already flushed. This means that the surface/pipes etc
>>> are changed, but note we still in the old XRRenderer(PixelDrawPipe)
>>> which actually should be disposed as well
>>>  - we try to use the new surface and got ClassCastException.
>>>  - After the fix we will start to draw the line again from
>>> "SG2D.drawLine" above, using new surface and the new PixelDrawPipe.
>>>
>>> The interesting thing is how we will work if revalidation will replace
>>> the surface to the same type(so ClassCastException will not occurred)
>>> but the pipe will be changed to the new? I cannot prove it but it
>>> seems that we will draw something to the new surface using the old
>>> PixelDrawPipe. (But this is only for the record if someone will work
>>> on this/or similar issues).
>>>
>>> And the test which reproduce the bug.
>>>
>>> Bug: https://bugs.openjdk.java.net/browse/JDK-8158072
>>> Webrev can be found at:
>>> http://cr.openjdk.java.net/~serb/8158072/webrev.00
>>>
>>> [1] https://bugs.openjdk.java.net/browse/JDK-7172749
>>>
>>
>
>