On Thu, Feb 01, 2018 at 03:39:51PM +0000, Will Deacon wrote: > > I could've gotten my brain in a twist or course, which isn't _that_ > > unusual. I never seem to be able to quite remember the holes you have > > with ll/sc on arm64 :-) > > Is smp_mb__before_atomic supposed to provide ordering guarantees if it's > used before a failed cmpxchg? If so, I think it's needed here because the > l.swa might not even execute. Or did I just invent another problem?
I think it should do so indeed (and afaik all our current archs are good that way).