[11u] RFR(S): 8241234: Unify monitor enter/exit runtime entries.

[Andrew Haley]

On 28/08/2020 17:19, Doerr, Martin wrote:

> 1. Some people assume that all of Oracle's 11u changes should get
> integrated into the open version.
> 2. Others only want to take them on demand with a good reason.
>
> I think there are good arguments for and against both ones.

> Personally, I think approach 1. is better at the beginning of an
> updates branch while it may be reasonable to switch at some point of
> time.
> At the moment, I still prefer to stay in sync with Oracle as far as
> we can.
>
> Regarding this change, I don't see a high risk.
> What it basically does is that it reuses better code which is
> already used by C2 for C1 and JVMCI compilers. So there's no
> substantial new code.
> It's tested by GraalVM and by our internal testing. There are no
> known issues with it.
>
> So I'd rather vote for taking it.

OK for this particular change. Please go ahead.

On the wider point:

A while ago I announced that we should not continue to independently
approve backports that had already been approved by Oracle. My
reasoning was that they'd done the work of balancing risk and reward,
and that for us to do it again when the decision would almost
inevitably be the same was not a good use of our time. After some very
noisy protests which insisted that this project must continue to
approve backports independently, I relented. But there is no point
retaining that right if we're never going to use it!

We should keep a close watch on Oracle backports for a while to try to
understand what their criteria are, and whether those criteria are a
good fit for our mission. If we see a significant number of minor
performance tweaks and "cleanups" we should reconsider our policy.

-- 
Andrew Haley  (he/him)
Java Platform Lead Engineer
Red Hat UK Ltd. <https://www.redhat.com>
https://keybase.io/andrewhaley
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