Re: [PATCH] RTC: Add mmap method to rtc character driver

Jim Gettys
2006-07-25T18:02:01Z

On Tue, 2006-07-25 at 19:55 +0200, Arjan van de Ven wrote:
> > @@ -265,6 +269,7 @@ irqreturn_t rtc_interrupt(int irq, void
> >
> > kill_fasync (&rtc_async_queue, SIGIO, POLL_IN);
> >
> > + *count_ptr = (*count_ptr)++;
>
> Hi,
>
> it's a cute idea, however 3 questions:
> 1) you probably want to add a few memory barriers around this, right?
> 2) why use the rtc and not the regular timer interrupt?
>
> (and
> 3) this will negate the power gain you get for tickless kernels, since
> now they need to start ticking again ;( )

The field only needs to get updated if you've scheduled something to
run...
- Jim

>
> Greetings,
> Arjan van de Ven
>
--
Jim Gettys
One Laptop Per Child