Re: Why Semaphore Hardware-Dependent?

Christoph Lameter
2006-08-29T15:57:12Z

On Tue, 29 Aug 2006, David Howells wrote:

> Because i386 (and x86_64) can do better by using XADDL/XADDQ.

And Ia64 would like to use fetchadd....

> CMPXCHG is not available on all archs, and may not be implemented on all archs
> through other atomic instructions.

Which arches do not support cmpxchg?