Re: [PATCH] iommu: Remove stub functions for !CONFIG_IOMMU_API

Ohad Ben-Cohen
2011-08-29T13:22:20Z

On Mon, Aug 29, 2011 at 4:05 PM, Roedel, Joerg <Joerg.Roedel@amd.com> wrote:
> So in this case you can skip this whole part when CONFIG_IOMMU_API is
> disabled

Sure, we can do something like this in the driver:

#ifdef CONFIG_IOMMU_API

int do_the_iommu_thing(..)
{
... call the IOMMU API as needed...
}

#else

int do_the_iommu_thing(..)
{
return 0;
}

#endif

Essentially, this means implementing the !CONFIG_IOMMU_API stubs in the driver.

Possible of course, but I think it's a bit neater to have that in one
place, where all drivers can use. Similar to !CONFIG_HWSPINLOCK,
!CONFIG_DEBUG_FS, ...

> This saves you even more .text size, no?

Not sure; I expect the code to be compiled out today when the IOMMU
API is called and CONFIG_IOMMU_API is not set.