>
> > -----Original Message-----
> > From: Dekel Peled [mailto:dek...@mellanox.com]
> > Sent: Monday, August 13, 2018 10:47 AM
> > To: dev@dpdk.org
> > Cc: Ori Kam <or...@mellanox.com>; Shahaf Shuler
> > <shah...@mellanox.com>
> > Subject: [RFC] ethdev: support metadata as flow rule criteria
> >
> > Current implementation of rte_flow allows match pattern of flow rule, based
> > on packet data or header fields.
> > This limits the application use of match patterns.
> >
> > For example, consider a vswitch application which controls a set of VMs,
> > connected with virtio, in a fabric with overlay of VXLAN.
> > Several VMs can have the same inner tuple, while the outer tuple is
> > different
> > and controlled by the vswitch (encap action).
> > For the vswtich to be able to offload the rule to the NIC, it must use a
> > unique
> > match criteria, independent from the inner tuple, to perform the encap
> > action.
> >
> > This RFC adds support for additional metadata to use as match pattern.
> > The metadata is an opaque item, fully controlled by the application.
> >
> > The use of metadata is relevant for egress rules only.
> > It can be set in the flow rule using the RTE_FLOW_ITEM_META.
> >
> > Application should set the packet metdata in the mbuf->metadata field, and
> > set the PKT_TX_METADATA flag in the mbuf->ol_flags.
> > The NIC will use the packet metadata as match criteria for relevant flow
> > rules.
> >
> > For example, to do an encap action depending on the VM id, the application
> > needs to configure 'match on metadata' rte_flow rule with VM id as
> > metadata, along with desired encap action.
> > When preparing an egress data packet, application will set VM id data in
> > mbuf metadata field and set PKT_TX_METADATA flag.
> >
> > PMD will send data packets to NIC, with VM id as metadata.
> > Egress flow on NIC will match metadata as done with other criteria.
> > Upon match on metadata (VM id) the appropriate encap action will be
> > performed.
> >
> > This RFC introduces metadata item type for rte_flow
> > RTE_FLOW_ITEM_META, along with corresponding struct
> > rte_flow_item_meta and ol_flag PKT_TX_METADATA.
> > It also enhances struct rte_mbuf with new data item, uint64_t metadata.
> >
> > Comments are welcome.
> >
> > Signed-off-by: Dekel Peled <dek...@mellanox.com>
> > ---
> > doc/guides/prog_guide/rte_flow.rst | 21 +++++++++++++++++++++
> > lib/librte_ethdev/rte_flow.c | 1 +
> > lib/librte_ethdev/rte_flow.h | 25 +++++++++++++++++++++++++
> > lib/librte_mbuf/rte_mbuf.h | 11 +++++++++++
> > 4 files changed, 58 insertions(+)
> >
> > diff --git a/doc/guides/prog_guide/rte_flow.rst
> > b/doc/guides/prog_guide/rte_flow.rst
> > index b305a72..b6e35f1 100644
> > --- a/doc/guides/prog_guide/rte_flow.rst
> > +++ b/doc/guides/prog_guide/rte_flow.rst
> > @@ -1191,6 +1191,27 @@ Normally preceded by any of:
> > - `Item: ICMP6_ND_NS`_
> > - `Item: ICMP6_ND_OPT`_
> >
> > +Item: ``META``
> > +^^^^^^^^^^^^^^
> > +
> > +Matches an application specific 64 bit metadata item.
> > +
> > +- Default ``mask`` matches any 64 bit value.
> > +
> > +.. _table_rte_flow_item_meta:
> > +
> > +.. table:: META
> > +
> > + +----------+----------+---------------------------+
> > + | Field | Subfield | Value |
> > + +==========+==========+===========================+
> > + | ``spec`` | ``data`` | 64 bit metadata value |
> > + +----------+--------------------------------------+
> > + | ``last`` | ``data`` | upper range value |
> > + +----------+----------+---------------------------+
> > + | ``mask`` | ``data`` | zeroed to match any value |
> > + +----------+----------+---------------------------+
> > +
> > Actions
> > ~~~~~~~
> >
> > diff --git a/lib/librte_ethdev/rte_flow.c b/lib/librte_ethdev/rte_flow.c
> > index
> > cff4b52..54e5ef8 100644
> > --- a/lib/librte_ethdev/rte_flow.c
> > +++ b/lib/librte_ethdev/rte_flow.c
> > @@ -66,6 +66,7 @@ struct rte_flow_desc_data {
> > sizeof(struct rte_flow_item_icmp6_nd_opt_sla_eth)),
> > MK_FLOW_ITEM(ICMP6_ND_OPT_TLA_ETH,
> > sizeof(struct rte_flow_item_icmp6_nd_opt_tla_eth)),
> > + MK_FLOW_ITEM(META, sizeof(struct rte_flow_item_meta)),
> > };
> >
> > /** Generate flow_action[] entry. */
> > diff --git a/lib/librte_ethdev/rte_flow.h b/lib/librte_ethdev/rte_flow.h
> > index
> > f8ba71c..b81c816 100644
> > --- a/lib/librte_ethdev/rte_flow.h
> > +++ b/lib/librte_ethdev/rte_flow.h
> > @@ -413,6 +413,15 @@ enum rte_flow_item_type {
> > * See struct rte_flow_item_mark.
> > */
> > RTE_FLOW_ITEM_TYPE_MARK,
> > +
> > + /**
> > + * [META]
> > + *
> > + * Matches a metadata value specified in mbuf metadata field.
> > + *
> > + * See struct rte_flow_item_meta.
> > + */
> > + RTE_FLOW_ITEM_TYPE_META,
> > };
> >
> > /**
> > @@ -849,6 +858,22 @@ struct rte_flow_item_gre { #endif
> >
> > /**
> > + * RTE_FLOW_ITEM_TYPE_META.
> > + *
> > + * Matches a specified metadata value.
> > + */
> > +struct rte_flow_item_meta {
> > + uint64_t data;
> > +};
> > +
> > +/** Default mask for RTE_FLOW_ITEM_TYPE_META. */ #ifndef __cplusplus
> > +static const struct rte_flow_item_meta rte_flow_item_meta_mask = {
> > + .data = RTE_BE64(UINT64_MAX),
> > +};
> > +#endif
> > +
> > +/**
> > * RTE_FLOW_ITEM_TYPE_FUZZY
> > *
> > * Fuzzy pattern match, expect faster than default.
> > diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h index
> > 9ce5d76..8f06a78 100644
> > --- a/lib/librte_mbuf/rte_mbuf.h
> > +++ b/lib/librte_mbuf/rte_mbuf.h
> > @@ -182,6 +182,11 @@
> > /* add new TX flags here */
> >
> > /**
> > + * This flag indicates that the metadata field in the mbuf is in use.
> > + */
> > +#define PKT_TX_METADATA (1ULL << 41)
> > +
> > +/**
> > * UDP Fragmentation Offload flag. This flag is used for enabling UDP
> > * fragmentation in SW or in HW. When use UFO, mbuf->tso_segsz is used
> > * to store the MSS of UDP fragments.
> > @@ -593,6 +598,12 @@ struct rte_mbuf {
> > */
> > struct rte_mbuf_ext_shared_info *shinfo;
> >
> > + /**
> > + * Application specific metadata value for flow rule match.
> > + * Valid if PKT_TX_METADATA is set.
> > + */
> > + uint64_t metadata;
> > +
Just one thought - with that change we'll have only 8 free bytes left inside
rte_mbuf.
Wonder tan this metadata field be combined within tx_offload or probably hash
fields?
Konstantin
> > } __rte_cache_aligned;
> >
> > /**
> > --
> > 1.8.3.1
