RFR: 8330303: Crash: assert(_target_jt == nullptr || _target_jt->vthread() == target_h()) failed

[Chris Plummer]

On Wed, 17 Apr 2024 00:29:52 GMT, Serguei Spitsyn <sspitsyn at openjdk.org> wrote:

> This is a simple fix of three similar asserts.
> The `_target_jt->jvmti_vthread()` has to be used instead of `_target_jt->vthread()`. 
> The `_target_jt->vthread()` can be outdated in some specific contexts as shown in the `hs_err` stack trace.
> 
> I've seen similar issue and already fixed it in this fragment of code:
> 
> class GetCurrentLocationClosure : public JvmtiUnitedHandshakeClosure {
>   . . .
>   void do_vthread(Handle target_h) {
>     assert(_target_jt == nullptr || !_target_jt->is_exiting(), "sanity check");
>     // use jvmti_vthread() as vthread() can be outdated
>     assert(_target_jt == nullptr || _target_jt->jvmti_vthread() == target_h(), "sanity check");
>     . . .
> 
> The issue above was fixed by replacing `_target_jt->vthread()` with `_target_jt->jvmti_vthread()`.
> 
> There are three places which need to be fixed the same way:
>  - `GetSingleStackTraceClosure::do_vthread(Handle target_h)`
>  - `SetForceEarlyReturn::do_vthread(Handle target_h)`
>  - `UpdateForPopTopFrameClosure::do_vthread(Handle target_h)`
> 
> Testing:
>  - Run mach5 tiers 1-6

Looks good.

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Marked as reviewed by cjplummer (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/18806#pullrequestreview-2018277846