[linux-dvb] Re: SMP problems with dvb-ttpci (was: Re: testing refactored drivers)

[Johannes Stezenbach <js@linuxtv.org>]

Ralph Metzler wrote:
> Johannes Stezenbach writes:
>  > OTOH, the way the host/firmware protocol is designed there is no
>  > advantage having two tasklets. The whole problem could be avoided
>  > by having one tasklet for both irqs. The only difficulty is to
>  > pass the isr value from av7110_irq() to the tasklet in a safe
>  > way.
> 
> If you reduce the number of debi port accesses you can keep almost 
> the whole stuff in IRQ without causing much delay (maybe in total even
> less than if you always schedule a tasklet) and you only have to put the 
> packet reception part of the debi IRQ into a tasklet.
> I did this in my driver version and this can probably be further
> optimized to have only one debi access (you need that anyway to 
> clear the IRQ) in almost all cases.

Yes. The important thing is to keep calls to dvb_dmx_swfilter_packets()
etc. out of the irq. The DEBI handling itself doesn't take much time.

Johannes