RE: [PATCH v3 00/14] add lookup fib nodes in graph library

["Morten Brørup" <mb@smartsharesystems.com>]

+TO: Robin Jarry, might have relevant feedback for such a node

> From: Ankur Dwivedi [mailto:adwivedi@marvell.com]
> Sent: Monday, 2 June 2025 08.36
> 
> This patch series adds two inbuilt nodes ip4_lookup_fib and
> ip6_lookup_fib in graph library. These nodes uses the existing
> Forwarding Information Base (FIB) library to create FIB, to do
> route addition and route lookup.
> 
> Two new commands (for ipv4 and ipv6) for providing the lookup mode
> is added in the dpdk-graph application. fib or lpm can be given as
> lookup mode. If these new lookup mode commands are not given, the
> dpdk-graph uses lpm (Longest Prefix Match) or lpm6 by default.
> If fib is given as lookup mode then the ip4_lookup_fib or
> ip6_lookup_fib
> nodes are used by the application.

@Ankur, @Vladimir, @Jerin,

A couple of high level questions...

1. Thread safety:
I'm not familiar with the thread safety models of the FIB and Graph libraries.
Is the FIB library thread safe, so one thread can invoke the FIB modify operation while other threads invoke the FIB lookup operation?
If it isn't, how does the Graph library make its use of the FIB library thread safe?

2. VRF support:
This looks like a global route table for the entire graph.
Shouldn't there be a route table per FIB node?
Or how are VRFs supported by the Graph library?
Or is there no requirement to support VRFs in the Graph library?

-Morten