RFR: 8272807: Permit use of memory concurrent with pretouch

[Kim Barrett]

On Tue, 24 Aug 2021 13:48:19 GMT, Kim Barrett <kbarrett at openjdk.org> wrote:

> > And this is x86_64. Whereas I see that AArch64 seems to do the call to the helper with `memory_order_conservative` always.
> 
> ??? Not sure where this `memory_order_conservative` might be. The new code use `memory_order_relaxed`.

Oh, the aarch64 atomics are going through common stubs that ignore the memory order.  Wow!  Why did I think they were using the gcc intrinsics and taking advantage of the memory order?

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PR: https://git.openjdk.java.net/jdk/pull/5215