RFR(XXS): 8207913: +EnableTracing crashes on jdk8u

[David Holmes]

Hi,

I dropped jdk8-dev at openjdk.java.net and added 
jdk8u-dev at openjdk.java.net to the cc line.

On 21/08/2018 8:38 AM, Liu, Xin wrote:
> Hi, Runtime develop,
> 
> Could you review this change basing on jdk8u?
> Problem: https://bugs.openjdk.java.net/browse/JDK-8207913
> Webrev: http://cr.openjdk.java.net/~phh/8207913/webrev.01/
> 
> JDK8u has this problem because Thread::current() is NULL when it handles global arguments at startup. OracleJDK8 doesn’t suffer from this issue.
> I found jdk12’s counterpart jfrEventClasses.hpp doesn’t have ResourceMark.  Removing it works for both with/without ttyLocker.

The ResourceMark has been there since the file was introduced in JDK 8. 
What has changed to cause this problem and when? If we remove the RM 
then we have to be sure no events that get traced will in fact rely on 
there being a RM present.

> We will check in jdk8u/hotspot if reviewers approve it.

There is a specific approval process that has to be followed after the 
change has been Reviewed.

http://openjdk.java.net/projects/jdk8u/approval-template.html

Thanks,
David

> Thanks,
> --lx
>