[PATCH 0/2] Fix nh_saddr caching.

[PATCH 0/2] Fix nh_saddr caching.

[David Miller]

Julian, the following two patches should take all of the
issues we discovered the other week wrt. nh_saddr caching.

First, we use a generation ID to invalidate cache nh_saddr
settings any time a device goes up or an IP address is
added/removed.

Second, we move fa_scope up to fib_info->fib_scope, so that
we always use the correct scope when computing the cached
nh_saddr.

Please review this carefully as this is delicate code.

Thanks!

Re: [PATCH 0/2] Fix nh_saddr caching.

[Julian Anastasov]

 	Hello,

On Thu, 24 Mar 2011, David Miller wrote:

> Julian, the following two patches should take all of the
> issues we discovered the other week wrt. nh_saddr caching.
>
> First, we use a generation ID to invalidate cache nh_saddr
> settings any time a device goes up or an IP address is
> added/removed.
>
> Second, we move fa_scope up to fib_info->fib_scope, so that
> we always use the correct scope when computing the cached
> nh_saddr.
>
> Please review this carefully as this is delicate code.

 	Looks very good. I checked the tree to make sure that
FIB_RES_PREFSRC, FIB_RES_DEV and fib_info_update_nh_saddr are
called only for res after successful fib_lookup. Even
fib_create_info calls fib_info_update_nh_saddr at a place
where nh_dev != NULL.

 	Only one thing: as the preferred addresses can be used
even if they are configured on downed interface there is no
gain to increase dev_addr_genid in fib_netdev_event(). If there are
address changes while some device is down all nh_saddr_genid
values for the downed device will be outdated because there is
no traffic that can refresh the nh_saddr.

 	Tests revealed unrelated problem in fib_trie, preparing
separate patch...

Regards

--
Julian Anastasov <ja@ssi.bg>