[openib-general] [PATCH 2/3] SA: add call to initialize ib_ah_attr from a path record

[Hal Rosenstock]

On Thu, 2006-05-18 at 23:09, Jason Gunthorpe wrote:
> On Thu, May 18, 2006 at 04:24:16PM -0700, Sean Hefty wrote:
> 
> > I should note that I compared the subnet prefixes to determine if the GRH 
> > should be used.  Reading back over the 'GRH flag in ib_ah_attr' thread, it 
> > looks like there's consensus that hop_limit > 1 is the check that we want.  
> > I will update the code accordingly.
> 
> I think it is also prudent to not use a GRH if the DGID's prefix is
> fe80::/64 (link local scope).

Agreed. This saves on the overhead in the local subnet case.

However, wouldn't the HopLimit returned from the SA in this case be 0 or
1 so why would that check be needed ?

If it is, I think the DGID prefix checking may be more than just this.

-- Hal