Re: [PATCH V2 0/3] riscv: atomic: Optimize AMO instructions usage

[Andrea Parri]

> > Seems to me that you are basically reverting 5ce6c1f3535f
> > ("riscv/atomic: Strengthen implementations with fences"). That commit
> > fixed an memory ordering issue, could you explain why the issue no
> > longer needs a fix?
> 
> I'm not reverting the prior patch, just optimizing it.
> 
> In RISC-V “A” Standard Extension for Atomic Instructions spec, it said:

With reference to the RISC-V herd specification at:

  https://github.com/riscv/riscv-isa-manual.git

the issue, better, lr-sc-aqrl-pair-vs-full-barrier seems to _no longer_
need a fix since commit:

  03a5e722fc0f ("Updates to the memory consistency model spec")

(here a template, to double check:

  https://github.com/litmus-tests/litmus-tests-riscv/blob/master/tests/non-mixed-size/HAND/LR-SC-NOT-FENCE.litmus )

I defer to Daniel/others for a "bi-section" of the prose specification.
;-)

  Andrea