Re: [patch 2/3] atomics: Provide rcuref - scalable reference counting

[Linus Torvalds]

On Tue, Feb 28, 2023 at 4:42 PM Linus Torvalds
<torvalds@xxxxxxxxxxxxxxxxxxx> wrote:
>
> And yes, that may mean that it should have some architecture-specific
> code (with fallback defaults for the generic case).

Another reason for architecture-specific code is that anybody who
doesn't have atomics and just relies on an LL/SC model is actually
better of *not* having any of this complexity.

In fact, the Intel RAO instruction set would likely do that on x86
too. With that alleged future "CMPccXADD", there likely is no longer
any advantage to this model of rcuref.

Now, I don't know when - if ever - said RAO instruction set extension
comes, but I'd hope that the new scalable reference counting would be
ready for it.

             Linus