On Wed, Jun 26, 2024 at 12:51:19PM GMT, Ilya Maximets wrote: > 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.
Thanks for the suggestion, will submit another version with this fix. Adrián > > 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