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

From: [email-masked] (Jiang Liu)
Date: Wed, 17 Sep 2014 11:07:13 +0800

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