tree a5b60f021fa257770d786ffec2e5c656c97d6c2e
parent d64a1f574a2957b4bcb06452d36cc1c6bf16e9fc
author Wei Wang <weiwan@google.com> 1561077400 -0700
committer David S. Miller <davem@davemloft.net> 1561321457 -0700

ipv6: convert rx data path to not take refcnt on dst

ip6_route_input() is the key function to do the route lookup in the
rx data path. All the callers to this function are already holding rcu
lock. So it is fairly easy to convert it to not take refcnt on the dst:
We pass in flag RT6_LOOKUP_F_DST_NOREF and do skb_dst_set_noref().
This saves a few atomic inc or dec operations and should boost
performance overall.
This also makes the logic more aligned with v4.

Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>