Re: Updated MSI Patches

Jeff Garzik
2003-08-12T18:49:12Z

Nakajima, Jun wrote:
> The issue with do_MSI() approach is that it's very similar to do_IRQ(),
> and we may have maintenance issues there. However, if we make a common

I agree

> do_MSI() code, that might be worth it, and I would expect much fewer
> architecture-dependent issues there, compared to do_IRQ (the common
> do_IRQ() hasn't happened yet as far as I know).

However, we have maintenance issues in this area as well :)

If you look at each architecture's implementation of do_IRQ, you can see
each implementation is strikingly similar... except for some subtle
differences. So there are arguments both ways: creating a common
do_IRQ may add maintenance value... but also create corner-case
problems for the arch maintainers.

So, IMO, do_IRQ is one special case where copying code may be preferred
over common code.

And I also feel the same way about do_MSI(). However, I have not looked
at non-ia32 MSI implementations to know what sort of issues exist.

Jeff