RFR: 8257831: Suspend with handshakes [v2]

[David Holmes]

On 7/04/2021 5:08 pm, Robbin Ehn wrote:
> On Wed, 7 Apr 2021 04:22:21 GMT, David Holmes <dholmes at openjdk.org> wrote:
> 
>>> By "treat this the same way as the others", you mean check and return either
>>> JVMTI_ERROR_THREAD_NOT_ALIVE or JVMTI_ERROR_THREAD_SUSPENDED as
>>> appropriate when we get a false back from JvmtiSuspendControl::suspend(current)?
>>>
>>> I'm not sure what this question is about:
>>>
>>>> it seem like we could be posting JvmtiExport::post_monitor_contended_enter() from the ensure_join() which locks the threadObj.
>>
>> I'm also unclear what Robbin is referring to. I go back to my original comment that surely JVMTI_ERROR_THREAD_NOT_ALIVE is impossible here?
> 
> We do a callback with a terminated thread, if the thread then in the agent tries to suspend itself we should return JVMTI_ERROR_THREAD_NOT_ALIVE.

How can you do a callback on a terminated thread here? The thread should 
only respond to the suspend request before it reaches the point in its 
exit where it would report "not alive".

David

> -------------
> 
> PR: https://git.openjdk.java.net/jdk/pull/3191
>