Re: Memory ordering issue in LWLockRelease, WakeupWaiters, WALInsertSlotRelease

Florian Pflug <fgp@phlo.org> writes:
> Another idea for a fix would be to conflate lwWaiting and lwWaitLink into one
> field. We could replace "lwWaiting" by "lwWaitLink != NULL" everywhere it's
> tested, and set lwWaitLink to some special non-NULL value (say 0x1) when we
> enqueue a PGPROC, instead of setting it to NULL and setting lwWaiting to true.

> We'd then depend on pointer-sized stores being atomic, which I think we depend
> on in other places already.

I don't believe that's true; neither that we depend on it now, nor that
it would be safe to do so.
        regards, tom lane