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

[Jim Gettys <jg@laptop.org>]

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


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