Re: Allow IP header alignment to be overriden

[jamal <hadi@xxxxxxxxxx>]

On Fri, 2004-06-11 at 01:35, David S. Miller wrote:
> On Fri, 11 Jun 2004 11:27:27 +1000
> Anton Blanchard <anton@xxxxxxxxx> wrote:
> 
> > The following patch creates skb_align and allows an architecture to
> > override it. Thoughts?
> 
> This transformation is not valid for a lot of drivers, that "2"
> in the reserve exists elsewhere in other calculations in the
> drivers.  For example, it is added to the RX skb allocation
> size.  Sometimes this '2' is there in non-trivial or hard to
> see ways (ie. it's implicitly in some DMA alignment value)

An interesting (annoying one) that falls into that category is
sb1250-mac.c::sbdma_align_skb()
shows up prominently in profiles

cheers,
jamal