RFR(XS): 8205195 NestedThreadsListHandleInErrorHandlingTest fails because hs_err doesn't contain _nested_thread_list_max

[David Holmes]

Hi Dan,

On 21/06/2018 10:18 AM, Daniel D. Daugherty wrote:
> Greetings,
> 
> I have a fix for a recent (very rare) Thread-SMR related test failure.
> 
> Since the fix is related to the ErrorHandling tests and affects hs_err_pid
> file generation, this code review is being sent to both the Runtime and
> the Serviceability teams. Please make sure you reply-all to any responses
> so we have complete review threads on both aliases.
> 
> Bug URL: https://bugs.openjdk.java.net/browse/JDK-8205195
> 
> Webrev URL: 
> http://cr.openjdk.java.net/~dcubed/8205195-webrev/0-for-jdk-jdk/
> 
> The bug itself contains analysis about the root cause of the bug and
> the comment updates to the code describes the no win scenario that the
> hs_err_pid file generation code is in. Of course, I also have a comment
> where I was able to harden the ErrorHandling tests. I did manage to
> resist the urge to mention the "Kobiyashi Maru" [1] in the new comments.
> 
> Testing: Mach5 builds-tier1,jdk-tier1,jdk-tier2,hs-tier1,hs-tier2,hs-tier3
>           on the usual Oracle platforms.
> 
> Thanks, in advance, for any comments, questions or suggestions.

I don't quite follow the fix. Won't you self-deadlock on acquiring the 
Threads_lock in the secondary error handler test, due to the recursive 
call to controlled_crash ?

David

> Dan
> 
> [1] https://www.urbandictionary.com/define.php?term=Kobayashi%20Maru
>