From: Benjamin LaHaise <bcrl@kvack.org>
Date: Sun, 29 Apr 2007 11:03:36 -0400

Hello

The patch below fixes a case where fib_find_info() is consume excessive 
amounts of CPU during the creation of 10000 PPP interfaces.  In access 
servers, each point to point link has the same local address, but a different 
destination and interface.  Because the device is not included in the hash 
calculation, the chain grows excessively large and we end up spinning the 
CPU walking the list.  As near as I can tell, this shouldn't have any negative 
sideeffects, but someone with a better understanding of fib_semantics.c will 
need to check over it.  Cheers,

fib_create_info() makes sure that fi->fib_nhs is always at least one.
So the conditional can be removed.  After a fib_info is create, it's
fi->fib_nhs is immutable, it doesn't change.

In fact there are some checks for fi->fib_nhs == 0 elsewhere in this
code, those are bogus too, and I imagine you saw those when coding
up this patch. :-)