RFR: 8373100: Genshen: Control thread can miss allocation failure notification [v3]

[Y. Srinivas Ramakrishna]

On Sat, 13 Dec 2025 00:41:01 GMT, William Kemper <wkemper at openjdk.org> wrote:

>> In some cases, the control thread may fail to observe an allocation failure. This results in the thread which failed to allocate waiting forever for the control thread to run a cycle. Depending on which thread fails to allocate, the process may not make progress.
>
> William Kemper has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains four additional commits since the last revision:
> 
>  - Merge remote-tracking branch 'jdk/master' into fix-missed-cancellation
>  - Improve comment
>  - Set requested gc cause under a lock when allocation fails
>  - Expand scope of control lock so that it can't miss cancellation notifications

Marked as reviewed by ysr (Reviewer).

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

PR Review: https://git.openjdk.org/jdk/pull/28665#pullrequestreview-3573980764