Hi,
On 2022-10-27 19:44:13 -0400, Tom Lane wrote:
> Turns out they have a pretty cute workaround for it, on HPPA and a couple of
> other atomics-less arches they still support. They've written short
> sequences that have the effect of CAS and are designed to store to memory
> only at the end. To make them atomic, libc asks the kernel "pretty please,
> if you happen to notice that I've been interrupted in the PC range from here
> to here, would you reset the PC to the start of that before returning?".
That sounds roughly like restartable sequences in the linux world - a pretty
cool feature. It's too bad that it's not yet available everywhere, it does
make some things a lot easier [to make performant].
> Anyway, I think the big picture here is that nowadays we could
> assume that the platform offers this feature.
Agreed.
Greetings,
Andres Freund
