Re: [CFT][RFC] HT scheduler

Arjan van de Ven
2003-12-14T16:55:08Z

On Sun, Dec 14, 2003 at 05:26:23PM +0100, Andi Kleen wrote:
> Arjan van de Ven <arjanv@redhat.com> writes:
> >
> > also keep in mind that current x86 processors all will internally
> > optimize out the lock prefix in UP mode or when the cacheline is owned
> > exclusive.... If HT matters here let the cpu optimize it out.....
>
> Are you sure they optimize it out in UP mode? IMHO this would break
> device drivers that use locked cycles to communicate with bus master
> devices (and which are not necessarily mapped uncachable/write combining)

uncachable regions are different obviously....