[OpenJDK 2D-Dev] bug 8146238 - Java Queue Flusher on MacOS
william at mathworks.com
Wed Sep 4 23:42:47 UTC 2019
Thanks, it looks like you made the change here:
Do you know if this change will work with Java 8?
On 8/24/19, 6:22 PM, "Sergey Bylokhov" <Sergey.Bylokhov at oracle.com> wrote:
I'll push it soon
On 8/24/19 10:27 am, Phil Race wrote:
> Since you proposed this version of the fix, do you want to push it ?
> On 8/24/19 5:09 AM, Alexey Ushakov wrote:
>> Hi Sergey,
>> The proposed solution looks good for me.
>> Best Regards,
>>> On 12 Aug 2019, at 12:29, Sergey Bylokhov <Sergey.Bylokhov at oracle.com> wrote:
>>> Hi, Phil, Alexey.
>>> I recheck this bug, and here is some of my thought:
>>> 1. We have two java classes:
>>> - GLX/CGL/WGL/GraphicsConfig which maintain the native structure WGL/GLX/CGL/GraphicsConfigInfo
>>> - GLX/CGL/WGL/SurfaceData which maintain the native structure CGL/GLXS/WGL/SDOps
>>> 2. The native structures should be disposed of by the "Disposer" machinery
>>> 3. The native part XXXSDOps has a pointer to the CGL/GraphicsConfigInfo
>>> 4. To prevent the usage of dangling pointer to the XXXGraphicsConfigInfo, the java part of XXXSDOps has a strong reference to the java part of XXXGraphicsConfigInfo
>>> The assumption at point 4 is not correct, it is possible that the native part of the XXXGraphicsConfigInfo could be disposed before XXXSDOps, and we will get a crash when we will try to dispose the XXXSDOps.
>>> Long time ago when it was implemented it works fine, because we never dispose the graphics configs, we read them on-start and use till the end of the application, even now we use this approach on Linux(JDK-8076313).
>>> So this bug existed on Linux, Windows and migrated to the macOS platform, but only on macOS and windows we can get a crash.
>>> I have rechecked the usage of the pointer from XXXSDOps to XXXGraphicsConfigInfo which caused a crash and think that we can get rid it, but it will required to change bunch of code on all platforms, so as a minimal fix I suggest this one:
>>> Just to store the reference to the GC till the moment it will not be used by the SurfaceData.
>>> On 8/7/19 10:56 am, Phil Race wrote:
>>>> This fix seems OK to me. Can you please do whatever re-evaluation you meant
>>>> as I'd like to pull it into jdk/client for Alexey (since he does not have current commit rights).
>>>> On 3/8/18 2:59 PM, Sergey Bylokhov wrote:
>>>>> Hi, Bill.
>>>>> Thank you for confirmation.
>>>>> On 08/03/2018 14:08, Bill York wrote:
>>>>>> 3. Is there a plan to get this bug fix into the JRE distributed by Oracle?
>>>>> I will reevaluate the fix for inclusion in jdk11.
>>> Best regards, Sergey.
Best regards, Sergey.
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