> > Makes sense. My pitch at the documentation after dropping READ_ONCE(): > > I'm confused again, I thought you wanted to keep READ_ONCE(). > > > > > /* > > * The return value of kvm_request_pending() is implicitly volatile > > why is that, actually? > > > * and must be protected from reordering by the caller. > > */ > > Can we be specific about what that means? (e.g. must be preceded by a > full smp_mb() - or whatever the case is). You can play devil's advocate both ways and argue that READ_ONCE is better, or that it is unnecessary hence worse. You can write good comments in either case. That's how I read Radim's message. But I think we all agree on keeping it in the end. > Perhaps we should just let Drew respin at this point, in case he's > confident about the right path, and then pick up from there? I agree. In any case, the memory barrier is the important part, but adding READ_ONCE is self-documenting and I prefer to have it. Paolo
