On 8/10/20 10:40 AM, Ori Kam wrote: > Hi Andrew, > > >> -----Original Message----- >> From: Andrew Rybchenko <arybche...@solarflare.com> >> >> On 8/7/20 8:02 AM, Ori Kam wrote: >>> Using the rte_flow action RSS types field, >>> may result in undefined outcome. >>> >>> For example selecting both UDP and TCP, >>> selecting TCP RSS type but the pattern is targeting UDP traffic. >>> another option is that the PMD doesn't support all requested types. >>> >>> Until now, it wasn't clear what will happen in such cases. >>> This commit clarify this issue by stating that the PMD >>> will work in the best-effort mode, and will fail >>> in case the requested type is not supported. >>> >>> Signed-off-by: Ori Kam <or...@mellanox.com> >>> --- >>> v3: >>> * Address ML comments. >>> >>> v2: >>> * Address ML comments. >>> --- >>> doc/guides/prog_guide/rte_flow.rst | 12 ++++++++++++ >>> 1 file changed, 12 insertions(+) >>> >>> diff --git a/doc/guides/prog_guide/rte_flow.rst >> b/doc/guides/prog_guide/rte_flow.rst >>> index 3e5cd1e..eada283 100644 >>> --- a/doc/guides/prog_guide/rte_flow.rst >>> +++ b/doc/guides/prog_guide/rte_flow.rst >>> @@ -1735,6 +1735,18 @@ unspecified "best-effort" settings from the >> underlying PMD, which depending >>> on the flow rule, may result in anything ranging from empty (single queue) >>> to all-inclusive RSS. >>> >>> +In case there are Non-applicable RSS types in the rule, >>> +Best effort will be used. >>> +This may be the result of: >>> + >>> +- Setting both UDP and TCP on the same rule. >>> + >>> +- Setting RSS types that don't match the requested pattern, >>> + for example, matching on UDP and hashing RSS on TCP. >>> + >>> +If requested RSS hash type is not supported in ``dev_info``. >>> +The flow creation will fail. >>> + >> Consider: >> If non-applicable for matching packets RSS types are requested, >> these RSS types are simply ignored. For example, it happens if: >> >> - Hashing of both TCP and UDP ports is requested >> (only one can present in a packet). >> >> - Requested RSS types contradict to flow rule pattern >> (e.g. pattern has UDP item, but RSS types contain TCP). >> >> If requested RSS types are not supported by the Ethernet device >> at all (not reported in ``dev_info.flow_type_rss_offloads``), >> the flow creation will fail. >> > Sure sounds good, but since this is just copying your words, > I will add your Signed-off-by to this patch, is that O.K?
OK >>> Note: RSS hash result is stored in the ``hash.rss`` mbuf field which >>> overlaps ``hash.fdir.lo``. Since `Action: MARK`_ sets the ``hash.fdir.hi`` >>> field only, both can be requested simultaneously. >>>
