On Mon, Jun 11, 2018 at 08:29:05PM -0700, David Miller wrote:
> I would like to bring up some problems with the current GSO
> implementation in SCTP.
> The most important for me right now is that SCTP uses
> "skb_gro_receive()" to build "GSO" frames :-(
> Really it just ends up using the slow path (basically, label 'merge'
> and onwards).
> So, using a GRO helper to build GSO packets is not great.
> I want to make major surgery here and the only way I can is if
> it is exactly the GRO demuxing path that uses skb_gro_receive().
> Those paths pass in the list head from the NAPI struct that initiated
> the GRO code paths. That makes it easy for me to change this to use a
> list_head or a hash chain.
> Probably in the short term SCTP should just have a private helper that
> builds the frag list, appending 'skb' to 'head'.
> In the long term, SCTP should use the page frags just like TCP to
> append the data when building GSO frames. Then it could actually be
> offloaded and passed into drivers without linearizing.
Sounds like a plan. Shouldn't be too hard to do it.
(I'm out on PTO, btw)