On Fri, 22 Feb 2008, Ingo Molnar wrote: > > * Gregory Haskins <gregory.haskins.ml@xxxxxxxxx> wrote: > > > My assumption is that the xchg() (inside update_current()) acts as an > > effective wmb(). If xchg() does not have this property, then this > > code is broken and patch 6/14 should also add a: > > xchg() is a strong implicit memory barrier, it implies smp_mb(). > (historic sidenote: it was the very first SMP primitive we had in > Linux.) OK, I've been proven wrong ;-) I was just thinking of how an arch would implement it. No need for memory barriers in just an xchg. But if Linux "implies it" then that's another story. Thanks, -- Steve /me learns something new everyday. - To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
