RFR: 8233343: Deprecate -XX:+CriticalJNINatives flag which implements Java…

[Robbin Ehn]

On Tue, 20 Oct 2020 11:41:17 GMT, Coleen Phillimore <coleenp at openjdk.org> wrote:

> This change deprecates the -XX:+CriticalJNINatives flag and removes the develop flag -XX:+StressCriticalJNINatives.
> See CSR for more details.
> This change also removes the lazy GC lock in the critical native transition, and runs the critical native function as
> thread_in_Java.  I add a safepoint check at the end of the native function and transition to native and poll again for
> the safepoint after the function if a safepoint is requested.  Tested with tier 1-6 (we have a few tests that use
> this).  And built on linux-x86-open,linux-s390x-open,linux-arm32-debug,linux-ppc64le-debug.

Thanks you @coleenp!
Looks good, really nice delta of -800 LOC !

-------------

Marked as reviewed by rehn (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/764