RFR(S): 8166679: JNI AsyncGetCallTrace replaces topmost frame name with <no Java callstack recorded> starting with Java 9 b133

[David Holmes]

Hi Chris,

On 21/10/2016 6:28 AM, Chris Plummer wrote:
> Hello,
>
> Please review the following:
>
> http://cr.openjdk.java.net/~cjplummer/8166679/webrev.00/webrev.hotspot/
> https://bugs.openjdk.java.net/browse/JDK-8166679
>
> The fix is to partially undo the changes for JDK-8159284. There are two
> places where the fix for JDK-8159284 added an extra check of the
> validity of the entry frame, but really only the first one is
> appropriate since for the second one we are not in an entry frame. More
> details can be found near the end of the bug comments.

This all seems reasonable. Addressing the regression is important. If 
this exposes a continuing issue with the reverted code then we can look 
at this further. The lack of reproducability makes this a difficult area 
to work in.

Thanks,
David

> Note I did a straight patch of the old version of the code. It could
> probably use some formatting and comment cleanup. I decided not to clean
> it up to make it easy to compare the current code with the original.
> I'll clean it up if you feel it would be best to.
>
> Tested by running KitchenSink more times than I can count, since that's
> where JDK-8159284 turned up. However, that's not proving much since I
> could not reproduce JDK-8159284 even without its fix in place (it also
> couldn't be reproduced at the time JDK-8159284 was was being
> investigated and fixed). For this reason I can't be 100% sure that
> JDK-8159284 is not being re-introduced with my changes.
>
> Also tested by running a very large set of tests trough RBT, close to
> what we do for PIT testing, minus product builds and a few tests that
> take a long time to run.
>
> Lastly, I also tested with the test case in the CR to make sure it now
> passes. Unforgettably it's not possible to add the test case as a jtreg
> test since it requires the installation of the Oracle Studio tools.
>
> thanks,
>
> Chris