On Wed, Apr 07, 2021 at 05:52:36PM +0200, Peter Zijlstra wrote: > On Wed, Apr 07, 2021 at 04:29:12PM +0200, Christoph Müllner wrote: > > The comparison with sparc64 is not applicable, as sparc64 does not > > have LL/SC instructions. > > Sparc64 has CAS, without hardware fwd progress. It has to do software > backoff for failed CAS in order to do software fwd progress. Again, the longer answer is that this applies identically to LL/SC and I'm sure we actually have (or had) an architecture in tree that did just that. I just cannot remember which architecture that was.
