RFR (XXS): 8172969: JVMTI spec: GetCurrentThread may return NULL in the early start phase

[David Holmes]

Looks good!

Thanks Serguei!

David

On 13/02/2017 5:33 PM, serguei.spitsyn at oracle.com wrote:
> Please, review a JDK 9 fix for the bug:
>   https://bugs.openjdk.java.net/browse/JDK-8172969
>
> Webrev:
> http://cr.openjdk.java.net/~sspitsyn/webrevs/2017/hotspot/8172969-jvmti-spec.hs1/
>
>
>
> Summary:
>
>   It was identified during the review of 8172261 that the GetCurrentThread
>   may return NULL during the early start phase. This issue existed with
>   the normal start phase in the initial JVM TI implementation (JDK 1.5).
>   Now the GetCurrentThread is Ok to call during the normal start phase
> as the
>   VMStart event is shifted to the point where the java.base is fully
> initialized.
>   But now the early VMStart event is at the same point where the VMStart
>   was in all previous releases.
>
>   The fix is a spec update saying that the GetCurrentThread may return
> NULL in the
>   early start phase when the java.lang.Thread class has not been
> initialized yet.
>
> Thanks,
> Serguei