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SubjectRe: "Verifying and Optimizing Compact NUMA-Aware Locks on Weak Memory Models"
On Fri, Aug 26, 2022 at 01:10:39PM -0400, Alan Stern wrote:

> > - some babbling about a missing propagation -- ISTR Linux if stuffed
> > full of them, specifically we require stores to auto propagate
> > without help from barriers
>
> Not a missing propagation; a late one.
>
> Don't understand what you mean by "auto propagate without help from
> barriers".

Linux hard relies on:

CPU0 CPU1

WRITE_ONCE(foo, 1); while (!READ_ONCE(foo));

making forward progress.

There were a few 'funny' uarchs that were broken, see for example commit
a30718868915f.

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