From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next v2] ipv4: fib: Replay events when registering
 FIB notifier
Date: Mon, 31 Oct 2016 14:24:06 -0700
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        kuznet@ms2.inr.ac.ru, jmorris@namei.org, yoshfuji@linux-ipv6.org,
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On Mon, 2016-10-31 at 23:13 +0200, idosch@idosch.org wrote:
> From: Ido Schimmel <idosch@mellanox.com>
> 
> When registering a FIB notifier block we should notify the caller of
> already existing FIB entries and rules, as it would otherwise have an
> incomplete view of the FIB tables. This is especially important for
> switchdev drivers that support FIB offloads. Failing to notify them of
> existing entries may lead to packet loss.
> 
> Upon registration, walk the leafs of all the routing tables and for each
> leaf send notification of existing FIB aliases. Similarly, when
> unregistering the notifier synthesize a deletion event, thereby
> relieving potential callers from the need to perform cleanup.
> 
> The above is consistent with the netdevice notification chain, where
> "registration and up events are replayed to the new notifier" upon
> registration.
> 
> Signed-off-by: Ido Schimmel <idosch@mellanox.com>
> Reviewed-by: Jiri Pirko <jiri@mellanox.com>



How well will this work for large FIB tables ?

Holding rtnl while sending thousands of skb will prevent consumers to
make progress ?