On Fri, 8 Dec 2006, David Howells wrote: > > It is the most universal atomic instruction that I know of. > > I think TAS-type things and XCHG-type things are more common.
Huh? The most popular architectures are i386 x86_64 sparc ia64 etc which all have one or the other form of cmpxchg (some issues with early sparc and i386). And yes the xchg was the first multiprocessor instruction and therefore is also available on very old processors. > In fact I think more things have LL/SC than have CMPXCHG. LL/SC can be easily used to come up with a cmpxchg equivalent. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/