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

[Daniel D. Daugherty]

On 2/13/17 12:33 AM, serguei.spit...@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/

src/share/vm/prims/jvmti.xml
    No comments.

Thumbs up!

Dan

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