tree ed61c22b342c82a64ca16e97a356acff94bc930c
parent 4115ded131645a7311a5d9afa9ff2b263dd91c2d
author Julian Anastasov <ja@ssi.bg> 1363859886 +0200
committer Pablo Neira Ayuso <pablo@netfilter.org> 1364855022 +0200

ipvs: optimize dst usage for real server

Currently when forwarding requests to real servers
we use dst_lock and atomic operations when cloning the
dst_cache value. As the dst_cache value does not change
most of the time it is better to use RCU and to lock
dst_lock only when we need to replace the obsoleted dst.
For this to work we keep dst_cache in new structure protected
by RCU. For packets to remote real servers we will use noref
version of dst_cache, it will be valid while we are in RCU
read-side critical section because now dst_release for replaced
dsts will be invoked after the grace period. Packets to
local real servers that are passed to local stack with
NF_ACCEPT need a dst clone.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off by: Hans Schillstrom <hans@schillstrom.com>
Signed-off-by: Simon Horman <horms@verge.net.au>