RFR: 8328944: NMT reports "unknown" memory

[Gerard Ziemski]

On Mon, 4 Nov 2024 08:23:13 GMT, Thomas Stuefe <stuefe at openjdk.org> wrote:

>> We use mtNone value in several functions default parameters, which may show up in NMT reports.
>> 
>> We address this, by removing the default value and forcing, where possible, for the callers to declare NMT tag that reflects the usage.
>> 
>> Eventually the goal would be not to use mtNone anywhere, but we are not there quite yet.
>> 
>> TODO: update copyrights.
>> 
>> Testing: undergoing MARCH5 tier1-5 ...
>
> src/hotspot/share/nmt/memReporter.cpp line 252:
> 
>> 250:    // report malloc'd memory
>> 251:   if (amount_in_current_scale(MAX2(malloc_memory->malloc_size(), pk_malloc)) > 0) {
>> 252:     print_malloc(malloc_memory->malloc_counter(), mtNMT);
> 
> Please revert, the original was correct. print_malloc is used for both summary and detail reports; for summary, we pass in mtNone deliberately since the report happens under a common tag.

I need to look into this further, but I think "mtAllocated" would be better.

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PR Review Comment: https://git.openjdk.org/jdk/pull/21843#discussion_r1844890055