Re: [Intel-gfx] [PATCH v3 2/4] drm/i915/pmu: Use kstat_irqs to get interrupt count

[Thomas Gleixner]

On Thu, Dec 10 2020 at 17:09, Tvrtko Ursulin wrote:
> On 10/12/2020 16:35, Thomas Gleixner wrote:
>> I'll send out a series addressing irq_to_desc() (ab)use all over the
>> place shortly. i915 is in there...
>
> Yep we don't need atomic, my bad. And we would care about the shared 
> interrupt line. And without atomic the extra accounting falls way below 
> noise.

You have to be careful though. If you make the accumulated counter 64
bit wide then you need to be careful vs. 32bit machines.

> So in the light of it all, it sounds best I just quickly replace our 
> abuse with private counting and then you don't have to deal with it in 
> your series.

I mostly have it. Still chewing on the 32bit vs. 64bit thing. And
keeping it in my series allows me to remove the export of irq_to_desc()
at the end without waiting for your tree to be merged.

Give me a few.

Thanks,

        tglx