RFR: 8355938: Addressed rare lost unpark bug 8074773 by pre-loading LockSupport.class

[Alan Bateman]

On Fri, 9 May 2025 02:45:16 GMT, David Holmes <dholmes at openjdk.org> wrote:

> The underlying issue is nested-parking as Alan notes. From re-reading 8074773, pre-loading in any class loaded by the boot loader, has no affect on the bug. The issue was the action taken by the AppLoader that involved creating an entry in the lockMap CHM. That particular bug-path was closed when CHM was rewritten to use object monitors (did it re-open again when Loom came along?).

No, it will still uses synchronized if there is contention and this will not consume the park permit when it's a virtual thread. Im not sure if Heinz ran into an issue, or just remember the issue from 2015, Heinz?

-------------

PR Comment: https://git.openjdk.org/jdk/pull/24952#issuecomment-2865320135