From 093b0f366567aa3fed85c316f832607069202b23 Mon Sep 17 00:00:00 2001 From: Adrian Moreno Date: Thu, 4 Jul 2024 10:56:52 +0200 Subject: [PATCH 01/10] net: psample: add user cookie Add a user cookie to the sample metadata so that sample emitters can provide more contextual information to samples. If present, send the user cookie in a new attribute: PSAMPLE_ATTR_USER_COOKIE. Reviewed-by: Michal Kubiak Acked-by: Eelco Chaudron Reviewed-by: Simon Horman Reviewed-by: Ido Schimmel Signed-off-by: Adrian Moreno Link: https://patch.msgid.link/20240704085710.353845-2-amorenoz@redhat.com Signed-off-by: Jakub Kicinski --- include/net/psample.h | 2 ++ include/uapi/linux/psample.h | 1 + net/psample/psample.c | 9 ++++++++- 3 files changed, 11 insertions(+), 1 deletion(-) diff --git a/include/net/psample.h b/include/net/psample.h index 0509d2d6be67..2ac71260a546 100644 --- a/include/net/psample.h +++ b/include/net/psample.h @@ -25,6 +25,8 @@ struct psample_metadata { out_tc_occ_valid:1, latency_valid:1, unused:5; + const u8 *user_cookie; + u32 user_cookie_len; }; struct psample_group *psample_group_get(struct net *net, u32 group_num); diff --git a/include/uapi/linux/psample.h b/include/uapi/linux/psample.h index e585db5bf2d2..e80637e1d97b 100644 --- a/include/uapi/linux/psample.h +++ b/include/uapi/linux/psample.h @@ -19,6 +19,7 @@ enum { PSAMPLE_ATTR_LATENCY, /* u64, nanoseconds */ PSAMPLE_ATTR_TIMESTAMP, /* u64, nanoseconds */ PSAMPLE_ATTR_PROTO, /* u16 */ + PSAMPLE_ATTR_USER_COOKIE, /* binary, user provided data */ __PSAMPLE_ATTR_MAX }; diff --git a/net/psample/psample.c b/net/psample/psample.c index a5d9b8446f77..b37488f426bc 100644 --- a/net/psample/psample.c +++ b/net/psample/psample.c @@ -386,7 +386,9 @@ void psample_sample_packet(struct psample_group *group, struct sk_buff *skb, nla_total_size(sizeof(u32)) + /* group_num */ nla_total_size(sizeof(u32)) + /* seq */ nla_total_size_64bit(sizeof(u64)) + /* timestamp */ - nla_total_size(sizeof(u16)); /* protocol */ + nla_total_size(sizeof(u16)) + /* protocol */ + (md->user_cookie_len ? + nla_total_size(md->user_cookie_len) : 0); /* user cookie */ #ifdef CONFIG_INET tun_info = skb_tunnel_info(skb); @@ -486,6 +488,11 @@ void psample_sample_packet(struct psample_group *group, struct sk_buff *skb, } #endif + if (md->user_cookie && md->user_cookie_len && + nla_put(nl_skb, PSAMPLE_ATTR_USER_COOKIE, md->user_cookie_len, + md->user_cookie)) + goto error; + genlmsg_end(nl_skb, data); genlmsg_multicast_netns(&psample_nl_family, group->net, nl_skb, 0, PSAMPLE_NL_MCGRP_SAMPLE, GFP_ATOMIC); From 03448444ae5c6e1de1ae7ff9fa19dc320eeb2d49 Mon Sep 17 00:00:00 2001 From: Adrian Moreno Date: Thu, 4 Jul 2024 10:56:53 +0200 Subject: [PATCH 02/10] net: sched: act_sample: add action cookie to sample If the action has a user_cookie, pass it along to the sample so it can be easily identified. Reviewed-by: Michal Kubiak Reviewed-by: Aaron Conole Acked-by: Eelco Chaudron Reviewed-by: Ido Schimmel Signed-off-by: Adrian Moreno Link: https://patch.msgid.link/20240704085710.353845-3-amorenoz@redhat.com Signed-off-by: Jakub Kicinski --- net/sched/act_sample.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/net/sched/act_sample.c b/net/sched/act_sample.c index a69b53d54039..2ceb4d141b71 100644 --- a/net/sched/act_sample.c +++ b/net/sched/act_sample.c @@ -167,7 +167,9 @@ TC_INDIRECT_SCOPE int tcf_sample_act(struct sk_buff *skb, { struct tcf_sample *s = to_sample(a); struct psample_group *psample_group; + u8 cookie_data[TC_COOKIE_MAX_SIZE]; struct psample_metadata md = {}; + struct tc_cookie *user_cookie; int retval; tcf_lastuse_update(&s->tcf_tm); @@ -189,6 +191,16 @@ TC_INDIRECT_SCOPE int tcf_sample_act(struct sk_buff *skb, if (skb_at_tc_ingress(skb) && tcf_sample_dev_ok_push(skb->dev)) skb_push(skb, skb->mac_len); + rcu_read_lock(); + user_cookie = rcu_dereference(a->user_cookie); + if (user_cookie) { + memcpy(cookie_data, user_cookie->data, + user_cookie->len); + md.user_cookie = cookie_data; + md.user_cookie_len = user_cookie->len; + } + rcu_read_unlock(); + md.trunc_size = s->truncate ? s->trunc_size : skb->len; psample_sample_packet(psample_group, skb, s->rate, &md); From c35d86a23029f1186e3c7a65df7c38b762fb0434 Mon Sep 17 00:00:00 2001 From: Adrian Moreno Date: Thu, 4 Jul 2024 10:56:54 +0200 Subject: [PATCH 03/10] net: psample: skip packet copy if no listeners If nobody is listening on the multicast group, generating the sample, which involves copying packet data, seems completely unnecessary. Return fast in this case. Reviewed-by: Aaron Conole Acked-by: Eelco Chaudron Reviewed-by: Ido Schimmel Reviewed-by: Simon Horman Signed-off-by: Adrian Moreno Link: https://patch.msgid.link/20240704085710.353845-4-amorenoz@redhat.com Signed-off-by: Jakub Kicinski --- net/psample/psample.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/psample/psample.c b/net/psample/psample.c index b37488f426bc..1c76f3e48dcd 100644 --- a/net/psample/psample.c +++ b/net/psample/psample.c @@ -376,6 +376,10 @@ void psample_sample_packet(struct psample_group *group, struct sk_buff *skb, void *data; int ret; + if (!genl_has_listeners(&psample_nl_family, group->net, + PSAMPLE_NL_MCGRP_SAMPLE)) + return; + meta_len = (in_ifindex ? nla_total_size(sizeof(u16)) : 0) + (out_ifindex ? nla_total_size(sizeof(u16)) : 0) + (md->out_tc_valid ? nla_total_size(sizeof(u16)) : 0) + From 7b1b2b60c63f070e0dfbe072ccaae13168b38d01 Mon Sep 17 00:00:00 2001 From: Adrian Moreno Date: Thu, 4 Jul 2024 10:56:55 +0200 Subject: [PATCH 04/10] net: psample: allow using rate as probability Although not explicitly documented in the psample module itself, the definition of PSAMPLE_ATTR_SAMPLE_RATE seems inherited from act_sample. Quoting tc-sample(8): "RATE of 100 will lead to an average of one sampled packet out of every 100 observed." With this semantics, the rates that we can express with an unsigned 32-bits number are very unevenly distributed and concentrated towards "sampling few packets". For example, we can express a probability of 2.32E-8% but we cannot express anything between 100% and 50%. For sampling applications that are capable of sampling a decent amount of packets, this sampling rate semantics is not very useful. Add a new flag to the uAPI that indicates that the sampling rate is expressed in scaled probability, this is: - 0 is 0% probability, no packets get sampled. - U32_MAX is 100% probability, all packets get sampled. Reviewed-by: Aaron Conole Acked-by: Eelco Chaudron Reviewed-by: Ido Schimmel Signed-off-by: Adrian Moreno Link: https://patch.msgid.link/20240704085710.353845-5-amorenoz@redhat.com Signed-off-by: Jakub Kicinski --- include/net/psample.h | 3 ++- include/uapi/linux/psample.h | 10 +++++++++- net/psample/psample.c | 3 +++ 3 files changed, 14 insertions(+), 2 deletions(-) diff --git a/include/net/psample.h b/include/net/psample.h index 2ac71260a546..c52e9ebd88dd 100644 --- a/include/net/psample.h +++ b/include/net/psample.h @@ -24,7 +24,8 @@ struct psample_metadata { u8 out_tc_valid:1, out_tc_occ_valid:1, latency_valid:1, - unused:5; + rate_as_probability:1, + unused:4; const u8 *user_cookie; u32 user_cookie_len; }; diff --git a/include/uapi/linux/psample.h b/include/uapi/linux/psample.h index e80637e1d97b..b765f0e81f20 100644 --- a/include/uapi/linux/psample.h +++ b/include/uapi/linux/psample.h @@ -8,7 +8,11 @@ enum { PSAMPLE_ATTR_ORIGSIZE, PSAMPLE_ATTR_SAMPLE_GROUP, PSAMPLE_ATTR_GROUP_SEQ, - PSAMPLE_ATTR_SAMPLE_RATE, + PSAMPLE_ATTR_SAMPLE_RATE, /* u32, ratio between observed and + * sampled packets or scaled probability + * if PSAMPLE_ATTR_SAMPLE_PROBABILITY + * is set. + */ PSAMPLE_ATTR_DATA, PSAMPLE_ATTR_GROUP_REFCOUNT, PSAMPLE_ATTR_TUNNEL, @@ -20,6 +24,10 @@ enum { PSAMPLE_ATTR_TIMESTAMP, /* u64, nanoseconds */ PSAMPLE_ATTR_PROTO, /* u16 */ PSAMPLE_ATTR_USER_COOKIE, /* binary, user provided data */ + PSAMPLE_ATTR_SAMPLE_PROBABILITY,/* no argument, interpret rate in + * PSAMPLE_ATTR_SAMPLE_RATE as a + * probability scaled 0 - U32_MAX. + */ __PSAMPLE_ATTR_MAX }; diff --git a/net/psample/psample.c b/net/psample/psample.c index 1c76f3e48dcd..f48b5b9cd409 100644 --- a/net/psample/psample.c +++ b/net/psample/psample.c @@ -497,6 +497,9 @@ void psample_sample_packet(struct psample_group *group, struct sk_buff *skb, md->user_cookie)) goto error; + if (md->rate_as_probability) + nla_put_flag(skb, PSAMPLE_ATTR_SAMPLE_PROBABILITY); + genlmsg_end(nl_skb, data); genlmsg_multicast_netns(&psample_nl_family, group->net, nl_skb, 0, PSAMPLE_NL_MCGRP_SAMPLE, GFP_ATOMIC); From aae0b82b46cb5004bdf82a000c004d69a0885c33 Mon Sep 17 00:00:00 2001 From: Adrian Moreno Date: Thu, 4 Jul 2024 10:56:56 +0200 Subject: [PATCH 05/10] net: openvswitch: add psample action Add support for a new action: psample. 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. Reviewed-by: Michal Kubiak Reviewed-by: Aaron Conole Reviewed-by: Ilya Maximets Acked-by: Eelco Chaudron Signed-off-by: Adrian Moreno Link: https://patch.msgid.link/20240704085710.353845-6-amorenoz@redhat.com Signed-off-by: Jakub Kicinski --- Documentation/netlink/specs/ovs_flow.yaml | 17 ++++++++ include/uapi/linux/openvswitch.h | 28 +++++++++++++ net/openvswitch/Kconfig | 1 + net/openvswitch/actions.c | 48 +++++++++++++++++++++++ net/openvswitch/flow_netlink.c | 32 ++++++++++++++- 5 files changed, 125 insertions(+), 1 deletion(-) diff --git a/Documentation/netlink/specs/ovs_flow.yaml b/Documentation/netlink/specs/ovs_flow.yaml index 4fdfc6b5cae9..46f5d1cd8a5f 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: psample + type: nest + nested-attributes: psample-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: psample-attrs + enum-name: ovs-psample-attr + name-prefix: ovs-psample-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..3dd653748725 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_PSAMPLE_COOKIE_MAX_SIZE 16 +/** + * enum ovs_psample_attr - Attributes for %OVS_ACTION_ATTR_PSAMPLE + * action. + * + * @OVS_PSAMPLE_ATTR_GROUP: 32-bit number to identify the source of the + * sample. + * @OVS_PSAMPLE_ATTR_COOKIE: An optional variable-length binary cookie that + * contains user-defined metadata. The maximum length is + * OVS_PSAMPLE_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 sample. + */ +enum ovs_psample_attr { + OVS_PSAMPLE_ATTR_GROUP = 1, /* u32 number. */ + OVS_PSAMPLE_ATTR_COOKIE, /* Optional, user specified cookie. */ + + /* private: */ + __OVS_PSAMPLE_ATTR_MAX +}; + +#define OVS_PSAMPLE_ATTR_MAX (__OVS_PSAMPLE_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_PSAMPLE: 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_PSAMPLE, /* Nested OVS_PSAMPLE_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..892d7e48fc5b 100644 --- a/net/openvswitch/actions.c +++ b/net/openvswitch/actions.c @@ -24,6 +24,11 @@ #include #include #include + +#if IS_ENABLED(CONFIG_PSAMPLE) +#include +#endif + #include #include "datapath.h" @@ -1299,6 +1304,40 @@ static int execute_dec_ttl(struct sk_buff *skb, struct sw_flow_key *key) return 0; } +#if IS_ENABLED(CONFIG_PSAMPLE) +static void execute_psample(struct datapath *dp, struct sk_buff *skb, + const struct nlattr *attr) +{ + struct psample_group psample_group = {}; + struct psample_metadata md = {}; + const struct nlattr *a; + int rem; + + nla_for_each_attr(a, nla_data(attr), nla_len(attr), rem) { + switch (nla_type(a)) { + case OVS_PSAMPLE_ATTR_GROUP: + psample_group.group_num = nla_get_u32(a); + break; + + case OVS_PSAMPLE_ATTR_COOKIE: + md.user_cookie = nla_data(a); + md.user_cookie_len = nla_len(a); + break; + } + } + + psample_group.net = ovs_dp_get_net(dp); + md.in_ifindex = OVS_CB(skb)->input_vport->dev->ifindex; + md.trunc_size = skb->len - OVS_CB(skb)->cutlen; + + psample_sample_packet(&psample_group, skb, 0, &md); +} +#else +static void execute_psample(struct datapath *dp, struct sk_buff *skb, + const struct nlattr *attr) +{} +#endif + /* Execute a list of actions against 'skb'. */ static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, struct sw_flow_key *key, @@ -1502,6 +1541,15 @@ static int do_execute_actions(struct datapath *dp, struct sk_buff *skb, ovs_kfree_skb_reason(skb, reason); return 0; } + + case OVS_ACTION_ATTR_PSAMPLE: + execute_psample(dp, skb, a); + OVS_CB(skb)->cutlen = 0; + if (nla_is_last(a, rem)) { + consume_skb(skb); + return 0; + } + break; } if (unlikely(err)) { diff --git a/net/openvswitch/flow_netlink.c b/net/openvswitch/flow_netlink.c index f224d9bcea5e..c92bdc4dfe19 100644 --- a/net/openvswitch/flow_netlink.c +++ b/net/openvswitch/flow_netlink.c @@ -64,6 +64,7 @@ static bool actions_may_change_flow(const struct nlattr *actions) case OVS_ACTION_ATTR_TRUNC: case OVS_ACTION_ATTR_USERSPACE: case OVS_ACTION_ATTR_DROP: + case OVS_ACTION_ATTR_PSAMPLE: break; case OVS_ACTION_ATTR_CT: @@ -2409,7 +2410,7 @@ static void ovs_nla_free_nested_actions(const struct nlattr *actions, int len) /* Whenever new actions are added, the need to update this * function should be considered. */ - BUILD_BUG_ON(OVS_ACTION_ATTR_MAX != 24); + BUILD_BUG_ON(OVS_ACTION_ATTR_MAX != 25); if (!actions) return; @@ -3157,6 +3158,28 @@ static int validate_and_copy_check_pkt_len(struct net *net, return 0; } +static int validate_psample(const struct nlattr *attr) +{ + static const struct nla_policy policy[OVS_PSAMPLE_ATTR_MAX + 1] = { + [OVS_PSAMPLE_ATTR_GROUP] = { .type = NLA_U32 }, + [OVS_PSAMPLE_ATTR_COOKIE] = { + .type = NLA_BINARY, + .len = OVS_PSAMPLE_COOKIE_MAX_SIZE, + }, + }; + struct nlattr *a[OVS_PSAMPLE_ATTR_MAX + 1]; + int err; + + if (!IS_ENABLED(CONFIG_PSAMPLE)) + return -EOPNOTSUPP; + + err = nla_parse_nested(a, OVS_PSAMPLE_ATTR_MAX, attr, policy, NULL); + if (err) + return err; + + return a[OVS_PSAMPLE_ATTR_GROUP] ? 0 : -EINVAL; +} + static int copy_action(const struct nlattr *from, struct sw_flow_actions **sfa, bool log) { @@ -3212,6 +3235,7 @@ static int __ovs_nla_copy_actions(struct net *net, const struct nlattr *attr, [OVS_ACTION_ATTR_ADD_MPLS] = sizeof(struct ovs_action_add_mpls), [OVS_ACTION_ATTR_DEC_TTL] = (u32)-1, [OVS_ACTION_ATTR_DROP] = sizeof(u32), + [OVS_ACTION_ATTR_PSAMPLE] = (u32)-1, }; const struct ovs_action_push_vlan *vlan; int type = nla_type(a); @@ -3490,6 +3514,12 @@ static int __ovs_nla_copy_actions(struct net *net, const struct nlattr *attr, return -EINVAL; break; + case OVS_ACTION_ATTR_PSAMPLE: + err = validate_psample(a); + if (err) + return err; + break; + default: OVS_NLERR(log, "Unknown Action type %d", type); return -EINVAL; From 71763d8a8203c28178d7be7f18af73d4dddb36ba Mon Sep 17 00:00:00 2001 From: Adrian Moreno Date: Thu, 4 Jul 2024 10:56:57 +0200 Subject: [PATCH 06/10] net: openvswitch: store sampling probability in cb. When a packet sample is observed, the sampling rate that was used is important to estimate the real frequency of such event. Store the probability of the parent sample action in the skb's cb area and use it in psample action to pass it down to psample module. Reviewed-by: Aaron Conole Acked-by: Eelco Chaudron Reviewed-by: Ilya Maximets Signed-off-by: Adrian Moreno Link: https://patch.msgid.link/20240704085710.353845-7-amorenoz@redhat.com Signed-off-by: Jakub Kicinski --- include/uapi/linux/openvswitch.h | 3 ++- net/openvswitch/actions.c | 20 +++++++++++++++++--- net/openvswitch/datapath.h | 3 +++ net/openvswitch/vport.c | 1 + 4 files changed, 23 insertions(+), 4 deletions(-) diff --git a/include/uapi/linux/openvswitch.h b/include/uapi/linux/openvswitch.h index 3dd653748725..3a701bd1f31b 100644 --- a/include/uapi/linux/openvswitch.h +++ b/include/uapi/linux/openvswitch.h @@ -649,7 +649,8 @@ enum ovs_flow_attr { * Actions are passed as nested attributes. * * Executes the specified actions with the given probability on a per-packet - * basis. + * basis. Nested actions will be able to access the probability value of the + * parent @OVS_ACTION_ATTR_SAMPLE. */ enum ovs_sample_attr { OVS_SAMPLE_ATTR_UNSPEC, diff --git a/net/openvswitch/actions.c b/net/openvswitch/actions.c index 892d7e48fc5b..101f9a23792c 100644 --- a/net/openvswitch/actions.c +++ b/net/openvswitch/actions.c @@ -1048,12 +1048,15 @@ static int sample(struct datapath *dp, struct sk_buff *skb, struct nlattr *sample_arg; int rem = nla_len(attr); const struct sample_arg *arg; + u32 init_probability; bool clone_flow_key; + int err; /* The first action is always 'OVS_SAMPLE_ATTR_ARG'. */ sample_arg = nla_data(attr); arg = nla_data(sample_arg); actions = nla_next(sample_arg, &rem); + init_probability = OVS_CB(skb)->probability; if ((arg->probability != U32_MAX) && (!arg->probability || get_random_u32() > arg->probability)) { @@ -1062,9 +1065,16 @@ static int sample(struct datapath *dp, struct sk_buff *skb, return 0; } + OVS_CB(skb)->probability = arg->probability; + clone_flow_key = !arg->exec; - return clone_execute(dp, skb, key, 0, actions, rem, last, - clone_flow_key); + err = clone_execute(dp, skb, key, 0, actions, rem, last, + clone_flow_key); + + if (!last) + OVS_CB(skb)->probability = init_probability; + + return err; } /* When 'last' is true, clone() should always consume the 'skb'. @@ -1311,6 +1321,7 @@ static void execute_psample(struct datapath *dp, struct sk_buff *skb, struct psample_group psample_group = {}; struct psample_metadata md = {}; const struct nlattr *a; + u32 rate; int rem; nla_for_each_attr(a, nla_data(attr), nla_len(attr), rem) { @@ -1329,8 +1340,11 @@ static void execute_psample(struct datapath *dp, struct sk_buff *skb, psample_group.net = ovs_dp_get_net(dp); md.in_ifindex = OVS_CB(skb)->input_vport->dev->ifindex; md.trunc_size = skb->len - OVS_CB(skb)->cutlen; + md.rate_as_probability = 1; - psample_sample_packet(&psample_group, skb, 0, &md); + rate = OVS_CB(skb)->probability ? OVS_CB(skb)->probability : U32_MAX; + + psample_sample_packet(&psample_group, skb, rate, &md); } #else static void execute_psample(struct datapath *dp, struct sk_buff *skb, diff --git a/net/openvswitch/datapath.h b/net/openvswitch/datapath.h index 0cd29971a907..9ca6231ea647 100644 --- a/net/openvswitch/datapath.h +++ b/net/openvswitch/datapath.h @@ -115,12 +115,15 @@ struct datapath { * fragmented. * @acts_origlen: The netlink size of the flow actions applied to this skb. * @cutlen: The number of bytes from the packet end to be removed. + * @probability: The sampling probability that was applied to this skb; 0 means + * no sampling has occurred; U32_MAX means 100% probability. */ struct ovs_skb_cb { struct vport *input_vport; u16 mru; u16 acts_origlen; u32 cutlen; + u32 probability; }; #define OVS_CB(skb) ((struct ovs_skb_cb *)(skb)->cb) diff --git a/net/openvswitch/vport.c b/net/openvswitch/vport.c index 972ae01a70f7..8732f6e51ae5 100644 --- a/net/openvswitch/vport.c +++ b/net/openvswitch/vport.c @@ -500,6 +500,7 @@ int ovs_vport_receive(struct vport *vport, struct sk_buff *skb, OVS_CB(skb)->input_vport = vport; OVS_CB(skb)->mru = 0; OVS_CB(skb)->cutlen = 0; + OVS_CB(skb)->probability = 0; if (unlikely(dev_net(skb->dev) != ovs_dp_get_net(vport->dp))) { u32 mark; From 60ccf62d3ceb37c89391e60d5ba402f52b720b62 Mon Sep 17 00:00:00 2001 From: Adrian Moreno Date: Thu, 4 Jul 2024 10:56:58 +0200 Subject: [PATCH 07/10] selftests: openvswitch: add psample action Add sample and psample action support to ovs-dpctl.py. Refactor common attribute parsing logic into an external function. Reviewed-by: Aaron Conole Signed-off-by: Adrian Moreno Link: https://patch.msgid.link/20240704085710.353845-8-amorenoz@redhat.com Signed-off-by: Jakub Kicinski --- .../selftests/net/openvswitch/ovs-dpctl.py | 162 +++++++++++++++++- 1 file changed, 161 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py index 182a09975975..dcc400a21a22 100644 --- a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py +++ b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py @@ -8,6 +8,7 @@ import argparse import errno import ipaddress import logging +import math import multiprocessing import re import socket @@ -60,6 +61,7 @@ OVS_FLOW_CMD_DEL = 2 OVS_FLOW_CMD_GET = 3 OVS_FLOW_CMD_SET = 4 +UINT32_MAX = 0xFFFFFFFF def macstr(mac): outstr = ":".join(["%02X" % i for i in mac]) @@ -281,6 +283,75 @@ def parse_extract_field( return str_skipped, data +def parse_attrs(actstr, attr_desc): + """Parses the given action string and returns a list of netlink + attributes based on a list of attribute descriptions. + + Each element in the attribute description list is a tuple such as: + (name, attr_name, parse_func) + where: + name: is the string representing the attribute + attr_name: is the name of the attribute as defined in the uAPI. + parse_func: is a callable accepting a string and returning either + a single object (the parsed attribute value) or a tuple of + two values (the parsed attribute value and the remaining string) + + Returns a list of attributes and the remaining string. + """ + def parse_attr(actstr, key, func): + actstr = actstr[len(key) :] + + if not func: + return None, actstr + + delim = actstr[0] + actstr = actstr[1:] + + if delim == "=": + pos = strcspn(actstr, ",)") + ret = func(actstr[:pos]) + else: + ret = func(actstr) + + if isinstance(ret, tuple): + (datum, actstr) = ret + else: + datum = ret + actstr = actstr[strcspn(actstr, ",)"):] + + if delim == "(": + if not actstr or actstr[0] != ")": + raise ValueError("Action contains unbalanced parentheses") + + actstr = actstr[1:] + + actstr = actstr[strspn(actstr, ", ") :] + + return datum, actstr + + attrs = [] + attr_desc = list(attr_desc) + while actstr and actstr[0] != ")" and attr_desc: + found = False + for i, (key, attr, func) in enumerate(attr_desc): + if actstr.startswith(key): + datum, actstr = parse_attr(actstr, key, func) + attrs.append([attr, datum]) + found = True + del attr_desc[i] + + if not found: + raise ValueError("Unknown attribute: '%s'" % actstr) + + actstr = actstr[strspn(actstr, ", ") :] + + if actstr[0] != ")": + raise ValueError("Action string contains extra garbage or has " + "unbalanced parenthesis: '%s'" % actstr) + + return attrs, actstr[1:] + + class ovs_dp_msg(genlmsg): # include the OVS version # We need a custom header rather than just being able to rely on @@ -299,7 +370,7 @@ class ovsactions(nla): ("OVS_ACTION_ATTR_SET", "ovskey"), ("OVS_ACTION_ATTR_PUSH_VLAN", "none"), ("OVS_ACTION_ATTR_POP_VLAN", "flag"), - ("OVS_ACTION_ATTR_SAMPLE", "none"), + ("OVS_ACTION_ATTR_SAMPLE", "sample"), ("OVS_ACTION_ATTR_RECIRC", "uint32"), ("OVS_ACTION_ATTR_HASH", "none"), ("OVS_ACTION_ATTR_PUSH_MPLS", "none"), @@ -318,8 +389,85 @@ class ovsactions(nla): ("OVS_ACTION_ATTR_ADD_MPLS", "none"), ("OVS_ACTION_ATTR_DEC_TTL", "none"), ("OVS_ACTION_ATTR_DROP", "uint32"), + ("OVS_ACTION_ATTR_PSAMPLE", "psample"), ) + class psample(nla): + nla_flags = NLA_F_NESTED + + nla_map = ( + ("OVS_PSAMPLE_ATTR_UNSPEC", "none"), + ("OVS_PSAMPLE_ATTR_GROUP", "uint32"), + ("OVS_PSAMPLE_ATTR_COOKIE", "array(uint8)"), + ) + + def dpstr(self, more=False): + args = "group=%d" % self.get_attr("OVS_PSAMPLE_ATTR_GROUP") + + cookie = self.get_attr("OVS_PSAMPLE_ATTR_COOKIE") + if cookie: + args += ",cookie(%s)" % \ + "".join(format(x, "02x") for x in cookie) + + return "psample(%s)" % args + + def parse(self, actstr): + desc = ( + ("group", "OVS_PSAMPLE_ATTR_GROUP", int), + ("cookie", "OVS_PSAMPLE_ATTR_COOKIE", + lambda x: list(bytearray.fromhex(x))) + ) + + attrs, actstr = parse_attrs(actstr, desc) + + for attr in attrs: + self["attrs"].append(attr) + + return actstr + + class sample(nla): + nla_flags = NLA_F_NESTED + + nla_map = ( + ("OVS_SAMPLE_ATTR_UNSPEC", "none"), + ("OVS_SAMPLE_ATTR_PROBABILITY", "uint32"), + ("OVS_SAMPLE_ATTR_ACTIONS", "ovsactions"), + ) + + def dpstr(self, more=False): + args = [] + + args.append("sample={:.2f}%".format( + 100 * self.get_attr("OVS_SAMPLE_ATTR_PROBABILITY") / + UINT32_MAX)) + + actions = self.get_attr("OVS_SAMPLE_ATTR_ACTIONS") + if actions: + args.append("actions(%s)" % actions.dpstr(more)) + + return "sample(%s)" % ",".join(args) + + def parse(self, actstr): + def parse_nested_actions(actstr): + subacts = ovsactions() + parsed_len = subacts.parse(actstr) + return subacts, actstr[parsed_len :] + + def percent_to_rate(percent): + percent = float(percent.strip('%')) + return int(math.floor(UINT32_MAX * (percent / 100.0) + .5)) + + desc = ( + ("sample", "OVS_SAMPLE_ATTR_PROBABILITY", percent_to_rate), + ("actions", "OVS_SAMPLE_ATTR_ACTIONS", parse_nested_actions), + ) + attrs, actstr = parse_attrs(actstr, desc) + + for attr in attrs: + self["attrs"].append(attr) + + return actstr + class ctact(nla): nla_flags = NLA_F_NESTED @@ -683,6 +831,18 @@ class ovsactions(nla): self["attrs"].append(["OVS_ACTION_ATTR_CT", ctact]) parsed = True + elif parse_starts_block(actstr, "sample(", False): + sampleact = self.sample() + actstr = sampleact.parse(actstr[len("sample(") : ]) + self["attrs"].append(["OVS_ACTION_ATTR_SAMPLE", sampleact]) + parsed = True + + elif parse_starts_block(actstr, "psample(", False): + psampleact = self.psample() + actstr = psampleact.parse(actstr[len("psample(") : ]) + self["attrs"].append(["OVS_ACTION_ATTR_PSAMPLE", psampleact]) + parsed = True + actstr = actstr[strspn(actstr, ", ") :] while parencount > 0: parencount -= 1 From c7815abbea457afa2a1ab3ded46d29c19da377d2 Mon Sep 17 00:00:00 2001 From: Adrian Moreno Date: Thu, 4 Jul 2024 10:56:59 +0200 Subject: [PATCH 08/10] selftests: openvswitch: add userspace parsing The userspace action lacks parsing support plus it contains a bug in the name of one of its attributes. This patch makes userspace action work. Reviewed-by: Aaron Conole Signed-off-by: Adrian Moreno Link: https://patch.msgid.link/20240704085710.353845-9-amorenoz@redhat.com Signed-off-by: Jakub Kicinski --- .../selftests/net/openvswitch/ovs-dpctl.py | 24 +++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py index dcc400a21a22..4ccf26f96327 100644 --- a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py +++ b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py @@ -589,13 +589,27 @@ class ovsactions(nla): print_str += "userdata=" for f in self.get_attr("OVS_USERSPACE_ATTR_USERDATA"): print_str += "%x." % f - if self.get_attr("OVS_USERSPACE_ATTR_TUN_PORT") is not None: + if self.get_attr("OVS_USERSPACE_ATTR_EGRESS_TUN_PORT") is not None: print_str += "egress_tun_port=%d" % self.get_attr( - "OVS_USERSPACE_ATTR_TUN_PORT" + "OVS_USERSPACE_ATTR_EGRESS_TUN_PORT" ) print_str += ")" return print_str + def parse(self, actstr): + attrs_desc = ( + ("pid", "OVS_USERSPACE_ATTR_PID", int), + ("userdata", "OVS_USERSPACE_ATTR_USERDATA", + lambda x: list(bytearray.fromhex(x))), + ("egress_tun_port", "OVS_USERSPACE_ATTR_EGRESS_TUN_PORT", int) + ) + + attrs, actstr = parse_attrs(actstr, attrs_desc) + for attr in attrs: + self["attrs"].append(attr) + + return actstr + def dpstr(self, more=False): print_str = "" @@ -843,6 +857,12 @@ class ovsactions(nla): self["attrs"].append(["OVS_ACTION_ATTR_PSAMPLE", psampleact]) parsed = True + elif parse_starts_block(actstr, "userspace(", False): + uact = self.userspace() + actstr = uact.parse(actstr[len("userspace(") : ]) + self["attrs"].append(["OVS_ACTION_ATTR_USERSPACE", uact]) + parsed = True + actstr = actstr[strspn(actstr, ", ") :] while parencount > 0: parencount -= 1 From b192bf12dbb015d37bb904d61751cad431ceb578 Mon Sep 17 00:00:00 2001 From: Adrian Moreno Date: Thu, 4 Jul 2024 10:57:00 +0200 Subject: [PATCH 09/10] selftests: openvswitch: parse trunc action The trunc action was supported decode-able but not parse-able. Add support for parsing the action string. Reviewed-by: Aaron Conole Signed-off-by: Adrian Moreno Link: https://patch.msgid.link/20240704085710.353845-10-amorenoz@redhat.com Signed-off-by: Jakub Kicinski --- .../testing/selftests/net/openvswitch/ovs-dpctl.py | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py index 4ccf26f96327..e8dc9af10d4d 100644 --- a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py +++ b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py @@ -863,6 +863,19 @@ class ovsactions(nla): self["attrs"].append(["OVS_ACTION_ATTR_USERSPACE", uact]) parsed = True + elif parse_starts_block(actstr, "trunc(", False): + parencount += 1 + actstr, val = parse_extract_field( + actstr, + "trunc(", + r"([0-9]+)", + int, + False, + None, + ) + self["attrs"].append(["OVS_ACTION_ATTR_TRUNC", val]) + parsed = True + actstr = actstr[strspn(actstr, ", ") :] while parencount > 0: parencount -= 1 From 30d772a03582bd10447af1bcdd1c731c89b54174 Mon Sep 17 00:00:00 2001 From: Adrian Moreno Date: Thu, 4 Jul 2024 10:57:01 +0200 Subject: [PATCH 10/10] selftests: openvswitch: add psample test Add a test to verify sampling packets via psample works. In order to do that, create a subcommand in ovs-dpctl.py to listen to on the psample multicast group and print samples. Reviewed-by: Aaron Conole Tested-by: Ilya Maximets Signed-off-by: Adrian Moreno Link: https://patch.msgid.link/20240704085710.353845-11-amorenoz@redhat.com Signed-off-by: Jakub Kicinski --- .../selftests/net/openvswitch/openvswitch.sh | 115 +++++++++++++++++- .../selftests/net/openvswitch/ovs-dpctl.py | 73 ++++++++++- 2 files changed, 182 insertions(+), 6 deletions(-) diff --git a/tools/testing/selftests/net/openvswitch/openvswitch.sh b/tools/testing/selftests/net/openvswitch/openvswitch.sh index 531951086d9c..bc71dbc18b21 100755 --- a/tools/testing/selftests/net/openvswitch/openvswitch.sh +++ b/tools/testing/selftests/net/openvswitch/openvswitch.sh @@ -20,7 +20,8 @@ tests=" nat_related_v4 ip4-nat-related: ICMP related matches work with SNAT netlink_checks ovsnl: validate netlink attrs and settings upcall_interfaces ovs: test the upcall interfaces - drop_reason drop: test drop reasons are emitted" + drop_reason drop: test drop reasons are emitted + psample psample: Sampling packets with psample" info() { [ "${ovs_dir}" != "" ] && @@ -105,12 +106,21 @@ ovs_netns_spawn_daemon() { shift netns=$1 shift - info "spawning cmd: $*" - ip netns exec $netns $* >> $ovs_dir/stdout 2>> $ovs_dir/stderr & + if [ "$netns" == "_default" ]; then + $* >> $ovs_dir/stdout 2>> $ovs_dir/stderr & + else + ip netns exec $netns $* >> $ovs_dir/stdout 2>> $ovs_dir/stderr & + fi pid=$! ovs_sbx "$sbx" on_exit "kill -TERM $pid 2>/dev/null" } +ovs_spawn_daemon() { + sbx=$1 + shift + ovs_netns_spawn_daemon $sbx "_default" $* +} + ovs_add_netns_and_veths () { info "Adding netns attached: sbx:$1 dp:$2 {$3, $4, $5}" ovs_sbx "$1" ip netns add "$3" || return 1 @@ -173,6 +183,19 @@ ovs_drop_reason_count() return `echo "$perf_output" | grep "$pattern" | wc -l` } +ovs_test_flow_fails () { + ERR_MSG="Flow actions may not be safe on all matching packets" + + PRE_TEST=$(dmesg | grep -c "${ERR_MSG}") + ovs_add_flow $@ &> /dev/null $@ && return 1 + POST_TEST=$(dmesg | grep -c "${ERR_MSG}") + + if [ "$PRE_TEST" == "$POST_TEST" ]; then + return 1 + fi + return 0 +} + usage() { echo echo "$0 [OPTIONS] [TEST]..." @@ -187,6 +210,92 @@ usage() { exit 1 } + +# psample test +# - use psample to observe packets +test_psample() { + sbx_add "test_psample" || return $? + + # Add a datapath with per-vport dispatching. + ovs_add_dp "test_psample" psample -V 2:1 || return 1 + + info "create namespaces" + ovs_add_netns_and_veths "test_psample" "psample" \ + client c0 c1 172.31.110.10/24 -u || return 1 + ovs_add_netns_and_veths "test_psample" "psample" \ + server s0 s1 172.31.110.20/24 -u || return 1 + + # Check if psample actions can be configured. + ovs_add_flow "test_psample" psample \ + 'in_port(1),eth(),eth_type(0x0806),arp()' 'psample(group=1)' &> /dev/null + if [ $? == 1 ]; then + info "no support for psample - skipping" + ovs_exit_sig + return $ksft_skip + fi + + ovs_del_flows "test_psample" psample + + # Test action verification. + OLDIFS=$IFS + IFS='*' + min_key='in_port(1),eth(),eth_type(0x0800),ipv4()' + for testcase in \ + "cookie to large"*"psample(group=1,cookie=1615141312111009080706050403020100)" \ + "no group with cookie"*"psample(cookie=abcd)" \ + "no group"*"psample()"; + do + set -- $testcase; + ovs_test_flow_fails "test_psample" psample $min_key $2 + if [ $? == 1 ]; then + info "failed - $1" + return 1 + fi + done + IFS=$OLDIFS + + ovs_del_flows "test_psample" psample + # Allow ARP + ovs_add_flow "test_psample" psample \ + 'in_port(1),eth(),eth_type(0x0806),arp()' '2' || return 1 + ovs_add_flow "test_psample" psample \ + 'in_port(2),eth(),eth_type(0x0806),arp()' '1' || return 1 + + # Sample first 14 bytes of all traffic. + ovs_add_flow "test_psample" psample \ + "in_port(1),eth(),eth_type(0x0800),ipv4()" \ + "trunc(14),psample(group=1,cookie=c0ffee),2" + + # Sample all traffic. In this case, use a sample() action with both + # psample and an upcall emulating simultaneous local sampling and + # sFlow / IPFIX. + nlpid=$(grep -E "listening on upcall packet handler" \ + $ovs_dir/s0.out | cut -d ":" -f 2 | tr -d ' ') + + ovs_add_flow "test_psample" psample \ + "in_port(2),eth(),eth_type(0x0800),ipv4()" \ + "sample(sample=100%,actions(psample(group=2,cookie=eeff0c),userspace(pid=${nlpid},userdata=eeff0c))),1" + + # Record psample data. + ovs_spawn_daemon "test_psample" python3 $ovs_base/ovs-dpctl.py psample-events + + # Send a single ping. + sleep 1 + ovs_sbx "test_psample" ip netns exec client ping -I c1 172.31.110.20 -c 1 || return 1 + sleep 1 + + # We should have received one userspace action upcall and 2 psample packets. + grep -E "userspace action command" $ovs_dir/s0.out >/dev/null 2>&1 || return 1 + + # client -> server samples should only contain the first 14 bytes of the packet. + grep -E "rate:4294967295,group:1,cookie:c0ffee data:[0-9a-f]{28}$" \ + $ovs_dir/stdout >/dev/null 2>&1 || return 1 + grep -E "rate:4294967295,group:2,cookie:eeff0c" \ + $ovs_dir/stdout >/dev/null 2>&1 || return 1 + + return 0 +} + # drop_reason test # - drop packets and verify the right drop reason is reported test_drop_reason() { diff --git a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py index e8dc9af10d4d..1e15b0818074 100644 --- a/tools/testing/selftests/net/openvswitch/ovs-dpctl.py +++ b/tools/testing/selftests/net/openvswitch/ovs-dpctl.py @@ -28,8 +28,10 @@ try: from pyroute2.netlink import genlmsg from pyroute2.netlink import nla from pyroute2.netlink import nlmsg_atoms + from pyroute2.netlink.event import EventSocket from pyroute2.netlink.exceptions import NetlinkError from pyroute2.netlink.generic import GenericNetlinkSocket + from pyroute2.netlink.nlsocket import Marshal import pyroute2 import pyroute2.iproute @@ -2460,10 +2462,70 @@ class OvsFlow(GenericNetlinkSocket): print("MISS upcall[%d/%s]: %s" % (seq, pktpres, keystr), flush=True) def execute(self, packetmsg): - print("userspace execute command") + print("userspace execute command", flush=True) def action(self, packetmsg): - print("userspace action command") + print("userspace action command", flush=True) + + +class psample_sample(genlmsg): + nla_map = ( + ("PSAMPLE_ATTR_IIFINDEX", "none"), + ("PSAMPLE_ATTR_OIFINDEX", "none"), + ("PSAMPLE_ATTR_ORIGSIZE", "none"), + ("PSAMPLE_ATTR_SAMPLE_GROUP", "uint32"), + ("PSAMPLE_ATTR_GROUP_SEQ", "none"), + ("PSAMPLE_ATTR_SAMPLE_RATE", "uint32"), + ("PSAMPLE_ATTR_DATA", "array(uint8)"), + ("PSAMPLE_ATTR_GROUP_REFCOUNT", "none"), + ("PSAMPLE_ATTR_TUNNEL", "none"), + ("PSAMPLE_ATTR_PAD", "none"), + ("PSAMPLE_ATTR_OUT_TC", "none"), + ("PSAMPLE_ATTR_OUT_TC_OCC", "none"), + ("PSAMPLE_ATTR_LATENCY", "none"), + ("PSAMPLE_ATTR_TIMESTAMP", "none"), + ("PSAMPLE_ATTR_PROTO", "none"), + ("PSAMPLE_ATTR_USER_COOKIE", "array(uint8)"), + ) + + def dpstr(self): + fields = [] + data = "" + for (attr, value) in self["attrs"]: + if attr == "PSAMPLE_ATTR_SAMPLE_GROUP": + fields.append("group:%d" % value) + if attr == "PSAMPLE_ATTR_SAMPLE_RATE": + fields.append("rate:%d" % value) + if attr == "PSAMPLE_ATTR_USER_COOKIE": + value = "".join(format(x, "02x") for x in value) + fields.append("cookie:%s" % value) + if attr == "PSAMPLE_ATTR_DATA" and len(value) > 0: + data = "data:%s" % "".join(format(x, "02x") for x in value) + + return ("%s %s" % (",".join(fields), data)).strip() + + +class psample_msg(Marshal): + PSAMPLE_CMD_SAMPLE = 0 + PSAMPLE_CMD_GET_GROUP = 1 + PSAMPLE_CMD_NEW_GROUP = 2 + PSAMPLE_CMD_DEL_GROUP = 3 + PSAMPLE_CMD_SET_FILTER = 4 + msg_map = {PSAMPLE_CMD_SAMPLE: psample_sample} + + +class PsampleEvent(EventSocket): + genl_family = "psample" + mcast_groups = ["packets"] + marshal_class = psample_msg + + def read_samples(self): + while True: + try: + for msg in self.get(): + print(msg.dpstr(), flush=True) + except NetlinkError as ne: + raise ne def print_ovsdp_full(dp_lookup_rep, ifindex, ndb=NDB(), vpl=OvsVport()): @@ -2530,7 +2592,7 @@ def main(argv): help="Increment 'verbose' output counter.", default=0, ) - subparsers = parser.add_subparsers() + subparsers = parser.add_subparsers(dest="subcommand") showdpcmd = subparsers.add_parser("show") showdpcmd.add_argument( @@ -2605,6 +2667,8 @@ def main(argv): delfscmd = subparsers.add_parser("del-flows") delfscmd.add_argument("flsbr", help="Datapath name") + subparsers.add_parser("psample-events") + args = parser.parse_args() if args.verbose > 0: @@ -2619,6 +2683,9 @@ def main(argv): sys.setrecursionlimit(100000) + if args.subcommand == "psample-events": + PsampleEvent().read_samples() + if hasattr(args, "showdp"): found = False for iface in ndb.interfaces: