Hi Yasumasa,
Could you explain a little bit the motivation to replace these vm operations
with handshakes?
Would be good, if you could add the goals as well to the JBS item.
Thanks, Richard.
-----Original Message-----
From: serviceability-dev <serviceability-dev-r...@openjdk.java.net> On Behalf
Of Yasumasa Suenaga
Sent: Montag, 24. August 2020 04:40
To: serviceability-dev <serviceability-dev@openjdk.java.net>
Subject: 8242427: JVMTI frame pop operations should use Thread-Local Handshakes
Hi all,
I want to hear your opinions about the change for JDK-8242427.
I'm trying to migrate following operations to direct handshake.
- VM_UpdateForPopTopFrame
- VM_SetFramePop
- VM_GetCurrentLocation
Some operations (VM_GetCurrentLocation and EnterInterpOnlyModeClosure) might be
called at safepoint, so I want to use JavaThread::active_handshaker() in
production VM to detect the process is in direct handshake or not.
However this function is available in debug VM only, so I want to hear the
reason why it is for debug VM only, and there are no problem to use it in
production VM. Of course another solutions are welcome.
webrev is here. It passed jtreg tests (vmTestbase/nsk/{jdi,jdwp,jvmti}
serviceability/{jdwp,jvmti})
http://cr.openjdk.java.net/~ysuenaga/JDK-8242427/proposal/
Thanks,
Yasumasa
