RFR: 8324828: Avoid multiple search of reserved regions during splitting

[Johan Sjölen]

On Mon, 26 Feb 2024 07:55:26 GMT, Afshin Zafari <azafari at openjdk.org> wrote:

> To reserve two consequent memory regions, developers need to reserve a large region and then split it into two sub parts. To register memory type `(MEMFLAGS) mtXXX` for a region another call to NMT API is needed for every sub part. Since at every NMT call a linked list of reserved regions is searched, therefore for every split operation there are three NMT calls and search in the list.
> This PR adds the memory flags of the two sub regions to the split API to avoid extra search in the list.
> 
> tiers1-5 tests passed

Nice!

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Marked as reviewed by jsjolen (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/18001#pullrequestreview-1900800256