Re: [PATCH v3] irqchip/tango: Don't use incorrect irq_mask_ack callback

Måns Rullgård
2017-07-25T13:29:22Z

Marc Gonzalez <marc_gonzalez@sigmadesigns.com> writes:

> On 25/07/2017 15:16, Måns Rullgård wrote:
>
>> What happened to the patch adding the proper combined function?
>
> It appears you're not CCed on v2.
>
> https://patchwork.kernel.org/patch/9859799/
>
> Doug wrote:
>> Yes, you understand correctly. The irq_mask_ack method is entirely
>> optional and I assume that is why this issue went undetected for so
>> long; however, it is slightly more efficient to combine the functions
>> (even if the ack is unnecessary) which is why I chose to do so for my
>> changes to the irqchip-brcmstb-l2 driver where I first discovered this
>> issue. How much value the improved efficiency has is certainly
>> debatable, but interrupt handling is one area where people might care
>> about such a small difference. As the irqchip-tango driver maintainer
>> you are welcome to decide whether or not the irq_mask_ack method makes
>> sense to you.
>
> My preference goes to leaving the irq_mask_ack callback undefined,
> and let the irqchip framework use irq_mask and irq_ack instead.

Why would you prefer the less efficient way?

--
Måns Rullgård