Re: Concurrency via isolated process/thread

[Ihor Radchenko]

Po Lu <luangruo@yahoo.com> writes:

>> Sure, but the whole chapter design shows that READ_ONCE/WRITE_ONCE is
>> not the best design. They go deep and complex just to avoid using it too
>> much.
>
> That's because READ_ONCE and WRITE_ONCE both have additional semantics
> beyond ensuring that loads and stores are coherently propagated and
> received to and from other CPUs.  For example, the compiler is not
> allowed to merge loads and stores, although it and the CPU are both
> allowed to reorder them.
>
> We don't have similar requirements in Emacs.

I've seen a couple of volatile variables in the code.
So, there is at least some fighting with GCC optimizations going on.

-- 
Ihor Radchenko // yantar92,
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