Re: [tipc-discussion] [PATCH net-next 0/8] tipc: add PLPMTUD probe and GSO offload

[Jon M. <jm...@re...>]

On 06/07/2021 14:22, Xin Long wrote:
> This patchset is to implement PLPMTUD and GSO for TIPC,
> Patch 1-5 are for PLPMTUD while 6-8 are for GSO.

I think this should be posted as two separate series, as they really 
implement two different features.

The problem I see with this is that you reduce MTU in patch #1, so
performance will suffer until the second series is adapted.

Unless there is a way around this the two series mut at least be
applied within the same release.

Also, if I understand this correctly, PLTMUD will work also for
the Ethernet bearer, so that jumbo frame capability can be detected?
I am uncertain about the value of this, since jumbo frame capability is 
already detected by the endpoint bearers, and I doubt that such frames
ever do more than one intra-subnet hop. But maybe I am wrong here? 
Anyway, this feature cannot do any harm even on Ethernet.

///jon

> 
> It gets some ideas from SCTP as their similarities like
> both are reliable datagram packets and possible to run
> over IP(v6)/UDP. But also it does some adjustments for
> TIPC.
> 
> Xin Long (8):
>    tipc: set the mtu for bearer properly for udp media
>    tipc: add the constants and variables for plpmtud
>    tipc: build probe and its reply in tipc_link_build_proto_msg
>    tipc: add probe send and state transition
>    tipc: add probe recv and state transition
>    tipc: add offload base
>    tipc: add software gso
>    tipc: add hardware gso
> 
>   include/uapi/linux/tipc_config.h |   6 --
>   net/tipc/Makefile                |   2 +-
>   net/tipc/bearer.c                |  23 ++++-
>   net/tipc/core.c                  |   3 +
>   net/tipc/link.c                  | 147 +++++++++++++++++++++++++++----
>   net/tipc/link.h                  |  29 ++++++
>   net/tipc/msg.c                   |   1 +
>   net/tipc/msg.h                   |   3 +
>   net/tipc/node.c                  |  15 +++-
>   net/tipc/offload.c               |  70 +++++++++++++++
>   net/tipc/udp_media.c             |  18 ++--
>   11 files changed, 287 insertions(+), 30 deletions(-)
>   create mode 100644 net/tipc/offload.c
>