Re: About irq_create_affinity_masks() for a platform device driver

[John Garry]

On 22/01/2020 10:59, Thomas Gleixner wrote:

Hi Thomas,

> John Garry <john.garry@xxxxxxxxxx> writes:
> > Would there be any issue with a SCSI platform device driver referencing
> > this function?
> >
> > So I have a multi-queue platform device, and I want to spread interrupts
> > over all possible CPUs, just like we can do for PCI MSI vectors. This
> > topic was touched on in [0].
> >
> > And, if so it's ok, could we export that same symbol?
>
> I think you will need something similar to what we have in the pci/msi
> code, but that shouldn't be in your device driver. So I'd rather create
> platform infrastructure for this and export that.

That would seem the proper thing do to.

So I was doing this for legacy hw as a cheap and quick performance 
boost, but I doubt how many other users there would be in future for any 
new API. Also, the effort could be more than the reward and so I may 
consider dropping the whole idea.

But I'll have a play with how the code could look now.

Cheers,
john