Re: [PATCH 0/7] atomics: generate atomic headers

[Mark Rutland]

On Tue, Jun 05, 2018 at 04:14:16PM +0200, Peter Zijlstra wrote:
> On Tue, Jun 05, 2018 at 02:58:23PM +0100, Mark Rutland wrote:
> 
> > Sure, it all works, it's just less than optimal as above, and also means
> > that we have to duplicate the ifdeffery for optional atomics -- once in
> > the instrumented atomics, then in the "real" atomics.
> > 
> > Whereas if we filled in the raw atomics atop of the arch atomics,
> > everything above that can assume the whole API is present, no ifdeffery
> > required.
> 
> Aah, I see your point now. I don't think performance is a particular
> concern when you enable K*SAN, but getting rid of a fair bunch of
> ifdeffery is always nice.

I agree that performance isn't a concern there when debugging, but I
would like to keep the overhead down when fuzzing.

Regardless, we'd have to move arches over to arch_atomic_* first, and
once that's done the raw_atomic_* stuff is fairly easy to implement by
reworking the scripts.

Thanks,
Mark.