JDK-8166862 : CMS needs klass_or_null_acquire
  • Type: Sub-task
  • Component: hotspot
  • Sub-Component: gc
  • Affected Version: 9
  • Priority: P2
  • Status: Resolved
  • Resolution: Fixed
  • OS: generic
  • CPU: generic
  • Submitted: 2016-09-28
  • Updated: 2021-02-05
  • Resolved: 2016-10-22
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JDK 8 JDK 9 Other
8u301Fixed 9 b146Fixed openjdk8u282Fixed
Description
Some of the places where CMS uses klass_or_null really should be using klass_or_null_acquire, in order to ensure the successful read of the klass preceeds later reads that are dependent on it.
Comments
Original patch does not apply to 8u-dev repo after path shuffling due to code changes in the surrounding context. 8u backport RFR thread: https://mail.openjdk.java.net/pipermail/jdk8u-dev/2020-November/012931.html
03-11-2020
Fix Request [8u] As mentioned in [1], JDK-8160369 have not been backported to JDK8u. This is necessary for RMO architectures like aarch64. Reviewing thread: https://mail.openjdk.java.net/pipermail/jdk8u-dev/2020-November/012931.html [1] https://mail.openjdk.java.net/pipermail/hotspot-gc-dev/2020-July/030313.html
03-11-2020