RFR: 8353263: Parallel: Remove locking in PSOldGen::resize

[Zhengyu Gu]

On Mon, 31 Mar 2025 09:45:23 GMT, Albert Mingkun Yang <ayang at openjdk.org> wrote:

> Simple removing the use of `PSOldGenExpand_lock` in resizing logic after full-gc, because the calling context is inside a safepoint.
> 
> Test: tier1-5

LGTM

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Marked as reviewed by zgu (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/24322#pullrequestreview-2736263356