On Wed, 28 May 2025 12:58:49 GMT, Alan Bateman <al...@openjdk.org> wrote:
>> src/hotspot/share/prims/jvmtiThreadState.hpp line 80:
>>
>>> 78: // Virtual Thread Mount State Transition (VTMS transition) mechanism
>>> 79: //
>>> 80: class JvmtiVTMSTransitionDisabler : public AnyObj {
>>
>> Why this change?
>
> It's used by VMThreadSnapshot::get_thread_snapshot. The transition disabling
> support is currently in the jvmti code. I think this is the first usage in a
> handshake op that isn't supporting a JVMTI function. Maybe in the future this
> could be separated.
> Why this change?
To be more clear about the change:
We need JvmtiVTMSTransitionDisabler for virtual threads only, for platform
threads handshake is enough. And currently for platform threads
JvmtiVTMSTransitionDisabler disables all mount/unmount transitions (and I'd
prefer to avoid this).
So we cannot create JvmtiVTMSTransitionDisabler on a stack (this is standard
use scenario), but need to create it conditionally by `new`/`delete`
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/25425#discussion_r2112491335
