RFR: 8348347: Cleanup JavaThread subclass support in SA [v2]

[Serguei Spitsyn]

On Thu, 6 Feb 2025 22:44:48 GMT, Chris Plummer <cjplummer at openjdk.org> wrote:

>> Cleanup SA JavaThread support. Details in first comment:
>> 
>> Testing:
>> - Tier1
>> - Tier2 svc
>> - Tier3
>> - Tier5 svc
>> - Local testing of debuggee using graal java compiler threads. Verified that the compiler threads shows up in jstack output if the property is set.
>
> Chris Plummer has updated the pull request incrementally with one additional commit since the last revision:
> 
>   update comments

This looks pretty good. Nice cleanup and simplification.
I've posted some nit and one question.

src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/runtime/ThreadStackTrace.java line 51:

> 49:         if (!thread.isJavaThread()) {
> 50:             return;
> 51:         }

Q: I wonder why does `!thread.isHiddenFromExternalView()` not used here. Have we always dumped the hidden from external view threads?

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Marked as reviewed by sspitsyn (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/23456#pullrequestreview-2610327458
PR Review Comment: https://git.openjdk.org/jdk/pull/23456#discussion_r1951738696