On Fri, Jan 11, 2008 at 08:35:43PM +0100, Joerg Sonnenberger wrote:
> On Thu, Jan 10, 2008 at 08:41:35PM +0000, David Laight wrote:
> > > Could it be this change ?
> > > - low = inb(IO_TIMER1 + TIMER_CNTR0);
> > > - high = inb(IO_TIMER1 + TIMER_CNTR0);
> > > - count = rtclock_tval - ((high <<8) | low);
> > > -
> > > + /* insb to make the read atomic */
> > > + insb(IO_TIMER1+TIMER_CNTR0, &rdval, 2);
> > > + count = rtclock_tval - rdval;
> >
> > I don't know, but I also have no reason to believe that the comment (and
> > hence the modified code) is correct.
>
> The only real diff is that you won't get interrupts processed in the
> middle, I think.
You think incorrectly :-) the x86 'rep' instructions are interruptable
between the iterations.
David
--
David Laight: david%l8s.co.uk@localhost