On Thu, 16 Nov 2023 19:02:39 GMT, Patricio Chilano Mateo
<pchilanom...@openjdk.org> wrote:
>> I'm suggesting to fix it this way for the unmounted case only:
>>
>> @@ -1976,6 +1976,13 @@ JvmtiHandshake::execute(JvmtiUnitedHandshakeClosure*
>> hs_cl, ThreadsListHandle* t
>> return;
>> }
>> if (target_jt == nullptr) { // unmounted virtual thread
>> + // JvmtiVTMSTransitionDisabler can start after the vthread executed
>> notifyJvmtiUnmount(), i.e.
>> + // the vthread is already outside the transition, but before changing
>> the state to TERMINATED.
>> + // Changing the state to TERMINATED is racy, so we check if the
>> continuation is done in advance.
>> + oop cont = java_lang_VirtualThread::continuation(target_h());
>> + if (jdk_internal_vm_Continuation::done(cont)) {
>> + return;
>> + }
>> hs_cl->do_vthread(target_h); // execute handshake closure callback on
>> current thread directly
>> }
>> }
>
> Sounds good. Is there a reason why not have the check inside
> JvmtiEnvBase::is_vthread_alive()?
If it is a part of the `JvmtiEnvBase::is_vthread_alive()` then it is racy for
mounted virtual threads.
It is not racy for unmounted virtual threads.
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PR Review Comment: https://git.openjdk.org/jdk/pull/16460#discussion_r1396456207
