On 6/25/24 22:51, Adrian Moreno wrote: > Add support for a new action: emit_sample. > > This action accepts a u32 group id and a variable-length cookie and uses > the psample multicast group to make the packet available for > observability. > > The maximum length of the user-defined cookie is set to 16, same as > tc_cookie, to discourage using cookies that will not be offloadable. > > Signed-off-by: Adrian Moreno <amore...@redhat.com> > --- > Documentation/netlink/specs/ovs_flow.yaml | 17 +++++++++ > include/uapi/linux/openvswitch.h | 28 ++++++++++++++ > net/openvswitch/Kconfig | 1 + > net/openvswitch/actions.c | 45 +++++++++++++++++++++++ > net/openvswitch/flow_netlink.c | 33 ++++++++++++++++- > 5 files changed, 123 insertions(+), 1 deletion(-) > > diff --git a/Documentation/netlink/specs/ovs_flow.yaml > b/Documentation/netlink/specs/ovs_flow.yaml > index 4fdfc6b5cae9..a7ab5593a24f 100644 > --- a/Documentation/netlink/specs/ovs_flow.yaml > +++ b/Documentation/netlink/specs/ovs_flow.yaml > @@ -727,6 +727,12 @@ attribute-sets: > name: dec-ttl > type: nest > nested-attributes: dec-ttl-attrs > + - > + name: emit-sample > + type: nest > + nested-attributes: emit-sample-attrs > + doc: | > + Sends a packet sample to psample for external observation. > - > name: tunnel-key-attrs > enum-name: ovs-tunnel-key-attr > @@ -938,6 +944,17 @@ attribute-sets: > - > name: gbp > type: u32 > + - > + name: emit-sample-attrs > + enum-name: ovs-emit-sample-attr > + name-prefix: ovs-emit-sample-attr- > + attributes: > + - > + name: group > + type: u32 > + - > + name: cookie > + type: binary > > operations: > name-prefix: ovs-flow-cmd- > diff --git a/include/uapi/linux/openvswitch.h > b/include/uapi/linux/openvswitch.h > index efc82c318fa2..8cfa1b3f6b06 100644 > --- a/include/uapi/linux/openvswitch.h > +++ b/include/uapi/linux/openvswitch.h > @@ -914,6 +914,31 @@ struct check_pkt_len_arg { > }; > #endif > > +#define OVS_EMIT_SAMPLE_COOKIE_MAX_SIZE 16 > +/** > + * enum ovs_emit_sample_attr - Attributes for %OVS_ACTION_ATTR_EMIT_SAMPLE > + * action. > + * > + * @OVS_EMIT_SAMPLE_ATTR_GROUP: 32-bit number to identify the source of the > + * sample. > + * @OVS_EMIT_SAMPLE_ATTR_COOKIE: A variable-length binary cookie that > contains > + * user-defined metadata. The maximum length is > OVS_EMIT_SAMPLE_COOKIE_MAX_SIZE > + * bytes. > + * > + * Sends the packet to the psample multicast group with the specified group > and > + * cookie. It is possible to combine this action with the > + * %OVS_ACTION_ATTR_TRUNC action to limit the size of the packet being > emitted. > + */ > +enum ovs_emit_sample_attr { > + OVS_EMIT_SAMPLE_ATTR_GROUP = 1, /* u32 number. */ > + OVS_EMIT_SAMPLE_ATTR_COOKIE, /* Optional, user specified cookie. */ > + > + /* private: */ > + __OVS_EMIT_SAMPLE_ATTR_MAX > +}; > + > +#define OVS_EMIT_SAMPLE_ATTR_MAX (__OVS_EMIT_SAMPLE_ATTR_MAX - 1) > + > /** > * enum ovs_action_attr - Action types. > * > @@ -966,6 +991,8 @@ struct check_pkt_len_arg { > * of l3 tunnel flag in the tun_flags field of OVS_ACTION_ATTR_ADD_MPLS > * argument. > * @OVS_ACTION_ATTR_DROP: Explicit drop action. > + * @OVS_ACTION_ATTR_EMIT_SAMPLE: Send a sample of the packet to external > + * observers via psample. > * > * Only a single header can be set with a single %OVS_ACTION_ATTR_SET. Not > all > * fields within a header are modifiable, e.g. the IPv4 protocol and fragment > @@ -1004,6 +1031,7 @@ enum ovs_action_attr { > OVS_ACTION_ATTR_ADD_MPLS, /* struct ovs_action_add_mpls. */ > OVS_ACTION_ATTR_DEC_TTL, /* Nested OVS_DEC_TTL_ATTR_*. */ > OVS_ACTION_ATTR_DROP, /* u32 error code. */ > + OVS_ACTION_ATTR_EMIT_SAMPLE, /* Nested OVS_EMIT_SAMPLE_ATTR_*. */ > > __OVS_ACTION_ATTR_MAX, /* Nothing past this will be accepted > * from userspace. */ > diff --git a/net/openvswitch/Kconfig b/net/openvswitch/Kconfig > index 29a7081858cd..2535f3f9f462 100644 > --- a/net/openvswitch/Kconfig > +++ b/net/openvswitch/Kconfig > @@ -10,6 +10,7 @@ config OPENVSWITCH > (NF_CONNTRACK && ((!NF_DEFRAG_IPV6 || NF_DEFRAG_IPV6) && \ > (!NF_NAT || NF_NAT) && \ > (!NETFILTER_CONNCOUNT || > NETFILTER_CONNCOUNT))) > + depends on PSAMPLE || !PSAMPLE > select LIBCRC32C > select MPLS > select NET_MPLS_GSO > diff --git a/net/openvswitch/actions.c b/net/openvswitch/actions.c > index 964225580824..1f555cbba312 100644 > --- a/net/openvswitch/actions.c > +++ b/net/openvswitch/actions.c > @@ -24,6 +24,11 @@ > #include <net/checksum.h> > #include <net/dsfield.h> > #include <net/mpls.h> > + > +#if IS_ENABLED(CONFIG_PSAMPLE) > +#include <net/psample.h> > +#endif > + > #include <net/sctp/checksum.h> > > #include "datapath.h" > @@ -1299,6 +1304,37 @@ static int execute_dec_ttl(struct sk_buff *skb, struct > sw_flow_key *key) > return 0; > } > > +static void execute_emit_sample(struct datapath *dp, struct sk_buff *skb, > + const struct sw_flow_key *key,
The 'key' is not used in the function. > + const struct nlattr *attr) > +{ > +#if IS_ENABLED(CONFIG_PSAMPLE) IIUC, the general coding style guideline is to compile out the whole function, instead of only the parts. i.e. something like: #if IS_ENABLED(CONFIG_PSAMPLE) static void execute_emit_sample(...) { <body> } #else #define execute_emit_sample(dp, skb, attr) #endif Otherwise, we'll also need to mark the arguments with __maybe_unused. The rest of the patch looks good to me. Best regards, Ilya Maximets. _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev