14/07/2022 14:54, Ding, Xuan: > Hi, > > From: Thomas Monjalon <tho...@monjalon.net> > > 14/07/2022 07:50, Ding, Xuan: > > > From: Thomas Monjalon <tho...@monjalon.net> > > > > 23/05/2022 16:20, xuan.d...@intel.com: > > > > > From: Xuan Ding <xuan.d...@intel.com> > > > > > > > > > > RTE_ETH_RX_OFFLOAD_HEADER_SPLIT offload was introduced some > > time > > > > ago > > > > > to substitute bit-field header_split in struct rte_eth_rxmode. It > > > > > allows to enable header split offload with the header size > > > > > controlled using split_hdr_size in the same structure. > > > > > > > > > > Right now, no single PMD actually supports > > > > > RTE_ETH_RX_OFFLOAD_HEADER_SPLIT with above definition. Many > > > > > examples and test apps initialize the field to 0 explicitly. The > > > > > most of drivers simply ignore split_hdr_size since the offload is > > > > > not advertised, but > > > > some double-check that its value is 0. > > > > > > > > > > So the RTE_ETH_RX_OFFLOAD_HEADER_SPLIT and split_header_size > > field > > > > > will be removed in DPDK 22.11. > > > > > > > > > > Signed-off-by: Xuan Ding <xuan.d...@intel.com> > > > > > --- > > > > > doc/guides/rel_notes/deprecation.rst | 4 ++++ > > > > > 1 file changed, 4 insertions(+) > > > > > > > > > > diff --git a/doc/guides/rel_notes/deprecation.rst > > > > > b/doc/guides/rel_notes/deprecation.rst > > > > > index 4e5b23c53d..b8114f29ed 100644 > > > > > --- a/doc/guides/rel_notes/deprecation.rst > > > > > +++ b/doc/guides/rel_notes/deprecation.rst > > > > > @@ -125,3 +125,7 @@ Deprecation Notices > > > > > applications should be updated to use the ``dmadev`` library > > > > > instead, > > > > > with the underlying HW-functionality being provided by the > > > > > ``ioat`` or > > > > > ``idxd`` dma drivers > > > > > + > > > > > +* ethdev: After bit-field header split was removed, the > > > > > +``RTE_ETH_RX_OFFLOAD_HEADER_SPLIT`` > > > > > +offload and the ``split_hdr_size`` field in structure > > > > > +``rte_eth_rxmode`` to enable header split offload are not > > > > > +supported in any > > > > PMDs. They will be removed in DPDK 22.11. > > > > > > > > It would have been good to talk about rte_eth_rxseg_split which is > > > > similar and configured per-queue. > > > > > > Thanks for your suggestion. > > > > > > But I'm a little confused, are you referring that I need to involve > > > protocol > > based buffer split? > > > About the deprecation of header split, I haven't realized its connection > > > to > > rte_eth_rxseg_split. > > > > What??? > > In old versions of your patch "ethdev: introduce protocol type based header > > split" > > you wrote: > > " > > A new proto field is introduced in the > > rte_eth_rxseg_split structure reserved field to specify header protocol > > type. > > With Rx offload flag RTE_ETH_RX_OFFLOAD_HEADER_SPLIT enabled and > > protocol type configured, PMD will split the ingress packets into two > > separate > > regions. > > " > > It has a long history... > It was corrected in v4 that RTE_ETH_RX_OFFLOAD_HEADER_SPLIT is used to enable > header > split offload with the header size controlled using "split_hdr_size". > But no single PMD actually supports RTE_ETH_RX_OFFLOAD_HEADER_SPLIT for this > purpose. > So we finally decide to deprecate this flag. > > http://patchwork.dpdk.org/project/dpdk/patch/20220402104109.472078-2-wenxuanx...@intel.com/ > > In following series, I use RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT instead. It is for > multi-segments packet > split. And it still needs a "proto_hdr" field in rte_eth_rxmode to configure > split location.
I know this history because I was the one asking you to deprecate this. But it seems you didn't get the big picture. > > > Currently there are 2 acks, add more PMD maintainers to help review > > > this deprecation notice for header split, thanks a lot! > > > > I cannot say my feeling strong enough. > > So IMO the deprecation for header split is not relevant with buffer split. > But we can still clean the code. > Hope it make things clearer. They are almost the same features. So when deprecating one, it is important to mention what remains. If needed RTE_ETH_RX_OFFLOAD_BUFFER_SPLIT can still be used and it is configured per-queue, while RTE_ETH_RX_OFFLOAD_HEADER_SPLIT was configurable per-port. Andrew, Ferruh, do you agree to improve this deprecation notice by adding above information?
