Commenting on Jon's response fist. Den tors 20 juni 2019 kl 13:26 skrev Xin Long <lucien....@gmail.com>: > > On Mon, Jun 17, 2019 at 10:28 PM Jon Maloy <jon.ma...@ericsson.com> wrote: > > Hi Xin, > > As I remember the discussion around introduction of UDP media a few years ago, the developer, Erik Huge, only chose to register TIPC as a udp tunnel user instead of regular udp user because it provides a more efficient way to receive packet in kernel space. > >With UDP tunnel, we could receive packet directly in a callback, while TIPC had to run in a work queue thread in order to read packets from the socket. The performance was largely dependant on TIPC message size, for large packets there was no measurable difference, but the tunnel approach was considerably faster for small packets than the kernel socket interface. I dont have the numbers, but i think i posted them on this list around 8 years ago.
>[...] > To implement this gso callback, we need to require an ipproto number for TIPC, > and register the callback into inet_offloads by inet_add_offload(). > And on tx path set: > skb->encapsulation = 1, > skb_shinfo(skb)->gso_type|= SKB_GSO_UDP_TUNNEL, > skb->inner_protocol_type = ENCAP_TYPE_IPPROTO. > > Then it will be called by: > dev_queue_xmit() .. -> skb_mac_gso_segment() ... -> > udp4_ufo_fragment() -> skb_udp_tunnel_segment() -> > skb_udp_tunnel_segment() -> tipc_gso_fragment() > > btw, do we have an official ipproto number for TIPC already? Not afak, but we have an IANA assigned UDP port for TIPC though, 6118. https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=tipc TIPC does: skb_set_inner_protocol <https://elixir.bootlin.com/linux/v5.2-rc5/ident/skb_set_inner_protocol>(skb , htons <https://elixir.bootlin.com/linux/v5.2-rc5/ident/htons>(ETH_P_TIPC <https://elixir.bootlin.com/linux/v5.2-rc5/ident/ETH_P_TIPC>)); which will in turn set skb_inner_protocol_type to ENCAP_TYPE_ETHER. So how about implementing something similar to what's done for ENCAP_TYPE_IPPROTO, but for ENCAP_TYPE_ETHER? In udp_offload.c, something in the line of: ... skb_udp_tunnel_segment(....) .... switch (skb->inner_protocol_type) { case ENCAP_TYPE_ETHER: protocol = skb->inner_protocol; ops = rcu_dereference(ether_offloads[protocol]); if (!ops || !ops->callbacks->gso_segment) goto out_unlock; gso_inner_segment = ops->callbacks.gso_segment; break; .... And obviously define ether_offloads, and corresponding ether_add_protocol and ether_add_offload functions. //E _______________________________________________ tipc-discussion mailing list tipc-discussion@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/tipc-discussion
