On Thu, 5 Feb 2026 02:29:53 GMT, Patricio Chilano Mateo
<[email protected]> wrote:
>> src/java.base/share/classes/jdk/internal/vm/ThreadSnapshot.java line 63:
>>
>>> 61: */
>>> 62: static ThreadSnapshot of(Thread thread) {
>>> 63: ThreadSnapshot snapshot = thread.isAlive() ? create(thread) :
>>> null;
>>
>> Looking at the implementation of `Thread.isAlive` for platform threads I'm
>> confused now. It checks `eetop != 0`, but we set it
>> [here](https://github.com/openjdk/jdk/blob/949370ab0e701cfcc68cb84dd0f91e5db41f4f45/src/hotspot/share/runtime/javaThread.cpp#L1732),
>> before we change the state to RUNNABLE
>> [here](https://github.com/openjdk/jdk/blob/949370ab0e701cfcc68cb84dd0f91e5db41f4f45/src/hotspot/share/runtime/thread.cpp#L408).
>> So I'm wondering if we could hit the assert added in the last update in
>> `ThreadSnapshotFactory::get_thread_snapshot`.
>
> Never mind, the `GetThreadSnapshotHandshakeClosure` handshake will not
> procede until the thread is started and becomes safepoint safe, which happens
> after the state is set to RUNNABLE. The attached case is also fine for a
> similar reason.
Thanks for the thorough analysis.
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PR Review Comment: https://git.openjdk.org/jdk/pull/29461#discussion_r2767772222
