{"id":2221015,"url":"http://patchwork.ozlabs.org/api/1.1/patches/2221015/?format=json","web_url":"http://patchwork.ozlabs.org/project/openvswitch/patch/20260408170613.587902-13-aconole@redhat.com/","project":{"id":47,"url":"http://patchwork.ozlabs.org/api/1.1/projects/47/?format=json","name":"Open vSwitch","link_name":"openvswitch","list_id":"ovs-dev.openvswitch.org","list_email":"ovs-dev@openvswitch.org","web_url":"http://openvswitch.org/","scm_url":"git@github.com:openvswitch/ovs.git","webscm_url":"https://github.com/openvswitch/ovs"},"msgid":"<20260408170613.587902-13-aconole@redhat.com>","date":"2026-04-08T17:06:08","name":"[ovs-dev,RFC,12/12] Documentation: Announce and describe the conntrack offload feature.","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"e406354bb1be4481a78c90d38383ca390c3bdb5e","submitter":{"id":67184,"url":"http://patchwork.ozlabs.org/api/1.1/people/67184/?format=json","name":"Aaron Conole","email":"aconole@redhat.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/openvswitch/patch/20260408170613.587902-13-aconole@redhat.com/mbox/","series":[{"id":499163,"url":"http://patchwork.ozlabs.org/api/1.1/series/499163/?format=json","web_url":"http://patchwork.ozlabs.org/project/openvswitch/list/?series=499163","date":"2026-04-08T17:05:56","name":"ct-offload: Introduce a conntrack offload infrastructure.","version":1,"mbox":"http://patchwork.ozlabs.org/series/499163/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2221015/comments/","check":"fail","checks":"http://patchwork.ozlabs.org/api/patches/2221015/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":["incoming@patchwork.ozlabs.org","dev@openvswitch.org"],"Delivered-To":["patchwork-incoming@legolas.ozlabs.org","ovs-dev@lists.linuxfoundation.org"],"Authentication-Results":["legolas.ozlabs.org;\n\tdkim=fail reason=\"signature verification failed\" (1024-bit key;\n unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256\n header.s=mimecast20190719 header.b=jNiOCTmW;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=openvswitch.org\n (client-ip=2605:bc80:3010::136; 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charset=\"us-ascii\"","Content-Transfer-Encoding":"7bit","Errors-To":"ovs-dev-bounces@openvswitch.org","Sender":"\"dev\" "},"content":"Signed-off-by: Aaron Conole \n---\n Documentation/automake.mk | 1 +\n Documentation/topics/index.rst | 1 +\n .../topics/userspace-conntrack-offloading.rst | 76 +++++++++++++++++++\n NEWS | 1 +\n 4 files changed, 79 insertions(+)\n create mode 100644 Documentation/topics/userspace-conntrack-offloading.rst","diff":"diff --git a/Documentation/automake.mk b/Documentation/automake.mk\nindex ea9459b555..7b84af79ba 100644\n--- a/Documentation/automake.mk\n+++ b/Documentation/automake.mk\n@@ -59,6 +59,7 @@ DOC_SOURCE = \\\n \tDocumentation/topics/tracing.rst \\\n \tDocumentation/topics/usdt-probes.rst \\\n \tDocumentation/topics/userspace-checksum-offloading.rst \\\n+\tDocumentation/topics/userspace-conntrack-offloading.rst \\\n \tDocumentation/topics/userspace-tso.rst \\\n \tDocumentation/topics/userspace-tx-steering.rst \\\n \tDocumentation/topics/windows.rst \\\ndiff --git a/Documentation/topics/index.rst b/Documentation/topics/index.rst\nindex 9ddb145dd4..871871a3dc 100644\n--- a/Documentation/topics/index.rst\n+++ b/Documentation/topics/index.rst\n@@ -56,6 +56,7 @@ OVS\n idl-compound-indexes\n ovs-extensions\n userspace-checksum-offloading\n+ userspace-conntrack-offloading\n userspace-tx-steering\n usdt-probes\n flow-visualization\ndiff --git a/Documentation/topics/userspace-conntrack-offloading.rst b/Documentation/topics/userspace-conntrack-offloading.rst\nnew file mode 100644\nindex 0000000000..26ba838c88\n--- /dev/null\n+++ b/Documentation/topics/userspace-conntrack-offloading.rst\n@@ -0,0 +1,76 @@\n+..\n+ Licensed under the Apache License, Version 2.0 (the \"License\"); you may\n+ not use this file except in compliance with the License. You may obtain\n+ a copy of the License at\n+\n+ http://www.apache.org/licenses/LICENSE-2.0\n+\n+ Unless required by applicable law or agreed to in writing, software\n+ distributed under the License is distributed on an \"AS IS\" BASIS, WITHOUT\n+ WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the\n+ License for the specific language governing permissions and limitations\n+ under the License.\n+\n+ Convention for heading levels in Open vSwitch documentation:\n+\n+ ======= Heading 0 (reserved for the title in a document)\n+ ------- Heading 1\n+ ~~~~~~~ Heading 2\n+ +++++++ Heading 3\n+ ''''''' Heading 4\n+\n+ Avoid deeper levels because they do not render well.\n+\n+=========================================\n+Userspace Datapath - Conntrack offloading\n+=========================================\n+\n+This document explains the internals of the Open vSwitch userspace connection\n+tracking offloading.\n+\n+Design\n+------\n+\n+Open vSwitch provides a modified BSD stack based connection tracking facility\n+which primarily processes packet-at-a-time into various state updates.\n+This runs inline with the pmd execution pipeline through the\n+`conntrack_execute` into the `process_one` call.\n+\n+The core of the offload mechanism is the `ct_offload_class` structure. This\n+structure defines the callbacks for offload providers, allowing them to\n+register for specific connection tracking events. Each offload provider\n+instance is placed in a list in priority order, and each one is called during\n+operation processing. There is a single bulked operations interface, but it\n+currently is limited to calling into each ops list facility-at-a-time.\n+\n+All offload is done under a large `ct_offload` lock to keep the offload\n+provider list coherent.\n+\n+Primary Connection Events\n+-------------------------\n+\n+The offload provider handles specific events corresponding to the lifecycle of\n+a connection. These are call-ins provided by the `ct_offload_class` structure.\n+\n+* Connection Add (conn_add) is triggered when a connection is created and\n+ committed to the connection list.\n+ When triggered, the provider receives the conn_add event to initialize\n+ tracking for the new connection.\n+* Connection Delete (conn_del) is triggered when a connection is removed.\n+ The provider receives the conn_del event to clean up resources.\n+* Connection Established (conn_established)\n+ This is a special event that occurs exactly once when the first\n+ reply-direction packet is seen for an offloaded connection.\n+ The netdev_in will contain the reply netdev. The offload provider should\n+ have access to the initial netdev from the conn_add and the reply direction\n+ from the conn_established events. This allows the provider to track both\n+ sides of the connection.\n+* Connection Update (conn_update) is called when the connection tracking (ct)\n+ expiration timer is set to run expiration processing for a connection.\n+ It asks for an update on the packet list. It returns the last-used timestamp\n+ in milliseconds since epoch, or 0 on failure.\n+\n+Configuration\n+-------------\n+Conntrack offload is configured as part of dpif offloading for userspace. It\n+utilizes the same configuration knob to enable offloading features.\ndiff --git a/NEWS b/NEWS\nindex 1a3044cbfb..80ee597abb 100644\n--- a/NEWS\n+++ b/NEWS\n@@ -3,6 +3,7 @@ Post-v3.7.0\n - Userspace datapath:\n * ARP/ND lookups for native tunnel are now rate limited. The holdout\n timer can be configured with 'tnl/neigh/retrans_time'.\n+ * Add preliminary support for conntrack offloading.\n \n \n v3.7.0 - 16 Feb 2026\n","prefixes":["ovs-dev","RFC","12/12"]}