From: Paolo Abeni <pab...@redhat.com> Date: Wed, 21 Jun 2017 11:45:31 +0200
> for connected socket, the incoming_cpu field in the sock struct > is not going to change frequently, but we are setting it > unconditionally for each packet. > > Since sk_incoming_cpu and sk_flags share the same cacheline, > and the latter is access by udp_recvmsg(), this cause a cache > miss for each packet for UDP connected socket. > > With this patch, we set the incoming cpu field only when the > ingress cpu really changes. > > This gives a small but measurable performance improvement for > connected UDP socket. > > Signed-off-by: Paolo Abeni <pab...@redhat.com> Applied.
