RFR: 8364280: NMTCommittedVirtualMemoryTracker.test_committed_virtualmemory_region_vm fails with assertion "negative distance"

[Johan Sjölen]

On Fri, 8 Aug 2025 08:52:48 GMT, Afshin Zafari <azafari at openjdk.org> wrote:

> The VirtualMemoryTracker API uses a tree internally for tracking the memory regions and their states/info. This tree should not be changed when looking for some regions. If not synch'ed, the nodes in the tree may change meanwhile and the retrieved info are not as expected. The unit test in this PR did not synch these looking up with VMT. The corresponding lock is used to address the problem.
> 
> Tests:
> local: linux-x64-debug NMTGtests
> mach5: tiers 1-5, {macosx-aarch64, linux-x64, windows-x64} x {debug, release}

Marked as reviewed by jsjolen (Reviewer).

test/hotspot/gtest/runtime/test_committed_virtualmemory.cpp line 70:

> 68:           found_stack_top = true;
> 69:         }
> 70:         if(i_addr < stack_top && i_addr >= cmr.base()) {

Could you add a space between the `if` and opening paren?

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PR Review: https://git.openjdk.org/jdk/pull/26689#pullrequestreview-3100043596
PR Review Comment: https://git.openjdk.org/jdk/pull/26689#discussion_r2262386191