JDK-8340826 : Should not send unload notification for scratch classes
  • Type: Bug
  • Component: hotspot
  • Sub-Component: jvmti
  • Affected Version: 24
  • Priority: P4
  • Status: Resolved
  • Resolution: Fixed
  • Submitted: 2024-09-24
  • Updated: 2024-10-07
  • Resolved: 2024-09-27
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JDK 24
24 b18Fixed
Related Reports
Relates :  
JDK-8318098 - Update jfr tests with corresponding requires flags
Relates :  
JDK-8341421 - Update 8340826 fix for jfr
Description
The jvmti class redefinition creates temporary scratch classes for it's own purposes. These classes are added to corresponding classloaders and might be unloaded. 
In this case the jvmti/jfr and log events are generated twice: for original class and for it's scratch.

The bug could be reproduced by jfr test
jdk/jfr/api/metadata/eventtype/TestUnloadingEventClass.java 
with '-Xcomp  -XX:TieredStopAtLevel=1' or with '-Xcomp'

The test hang because got 2 events while waiting for one.
Comments
Changeset: 12de4fbc Branch: master Author: Leonid Mesnik <lmesnik@openjdk.org> Date: 2024-09-27 15:02:01 +0000 URL: https://git.openjdk.org/jdk/commit/12de4fbce7a314a1c5c84340526cd65b9a4a29d1
27-09-2024
A pull request was submitted for review. Branch: master URL: https://git.openjdk.org/jdk/pull/21166 Date: 2024-09-24 16:29:36 +0000
24-09-2024