[RFC Part2 v1 02/21] genirq: Introduce helper functions to support stacked irq_chip

Jiang Liu
2014-09-17T03:07:13Z

On 2014/9/17 1:45, Thomas Gleixner wrote:
> On Thu, 11 Sep 2014, Jiang Liu wrote:
>> +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
>> +void irq_chip_ack_parent(struct irq_data *data)
>> +{
>> + data = data->parent_data;
>> + if (data && data->chip && data->chip->irq_ack)
>> + data->chip->irq_ack(data);
>
> Why is this restricted to a single parent level and does not go down
> the whole stack?
Hi Thomas,
It happens to work on x86, and we want to achieve a bit
performance advantage by not walking down the whole stack.
If preferred, I will change it to walk the whole stack.
Regards!
Gerry

>
> Thanks,
>
> tglx
>