RFR: 8337217: Port VirtualMemoryTracker to use VMATree [v31]

[Afshin Zafari]

On Wed, 26 Feb 2025 12:31:39 GMT, Johan Sjölen <jsjolen at openjdk.org> wrote:

>> Afshin Zafari has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   reviews applied.
>
> test/hotspot/gtest/nmt/test_vmatree.cpp line 221:
> 
>> 219:   EXPECT_EQ(-50, diff.tag[NMTUtil::tag_to_index(mtTest)].commit);
>> 220: }
>> 221: 
> 
> What's going on with this test?

It checks the `use_tag_inplace` in committing a region, by passing `true` to the last parameter of the `VMATree::commit_mapping`. It is expected that the existing tag from the previous region to be copied to this new region. The mem tag of the `rd2` (`mtNone`) should not be used for the new committed region.

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PR Review Comment: https://git.openjdk.org/jdk/pull/20425#discussion_r1971643555