From patchwork Sat Sep 30 14:35:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jamal Hadi Salim X-Patchwork-Id: 13405141 X-Patchwork-Delegate: kuba@kernel.org Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3FB10156E6 for ; Sat, 30 Sep 2023 14:36:03 +0000 (UTC) Received: from mail-vs1-xe2f.google.com (mail-vs1-xe2f.google.com [IPv6:2607:f8b0:4864:20::e2f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7B2A8100 for ; Sat, 30 Sep 2023 07:36:00 -0700 (PDT) Received: by mail-vs1-xe2f.google.com with SMTP id ada2fe7eead31-4528cba7892so7221334137.0 for ; Sat, 30 Sep 2023 07:36:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mojatatu-com.20230601.gappssmtp.com; s=20230601; t=1696084559; x=1696689359; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=HMT7GpYY5wKVo9A9jnqGQCAThU2ktlVPWLpYbBTG3l0=; b=2tFBWYcntoGeXkbuUq+zjttQUMgRYR/aOsWPrVv7nmQuOzIxJvCbExOKbwZtKtUGLY WNEpbaf8sPeqedwT5W+nEbZ4mbY9pHJlU6wIVk88oouTIvPdgBZWORGgfSsX0N+znMKF ni4p8Lri0zvi/d2eEdJq7LVuPMr1QJVmPxfFQYz16e+76LR4lvKEMxpMwaUPcpBSWF1v 0a7Ud8EBTBCGoMGOOyZXdXJB9FDVBKaQlDc0r6EdtzliC8q3IlXHuzez/K0gNxQmVIJv onjy2NYq2+Iyg3326Wf41d1oN1m9hibkbOKYzoC3Fh+RtQI5OVUJpXC0XrbUoBhlYwje /XCQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696084559; x=1696689359; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=HMT7GpYY5wKVo9A9jnqGQCAThU2ktlVPWLpYbBTG3l0=; b=v5H8Ug+GCOUCre06tiBcWge715+82OdKYZR+AJSSlKVyJRFF43zdAGGDK+iH8Oo1nc vZ8+162w+tJ5NuLRxemPc9Y053u04ZBh+ToBRwROfDKIW9JRHdzNYeepkxH7YSCYgttZ wZNV5zPymaBQG2jhrKIIK49SCAcaqA4fMYT3aciRNkh/8A/LMgKZy2AiWW6DPKCXYeNp 27+Fulnw1yhtjDt+CWNFHqA/9x8phlnqO+pYMqQvPmHxQ05C/zOoQB2UdaKvcX7zW08x ewoG9mm20yjUAsbw+w6YLl8ZcruLqF0TWuXx0PDwQn+GHa006fUdtL8ZZ64DoTkT/9/5 2iSg== X-Gm-Message-State: AOJu0YwMoJWV0vDJVIk3ITOrS0w74CDsfWQZtsEfOWnM4EsIi4M5hDw2 DsGWPAy630qSln7xQQIliXOpGyITjba1156z22g= X-Google-Smtp-Source: AGHT+IGBER2PBO7IdIycsoi1wr8kXjehiRUiJ6Ymsv97/z5LkWkA9jQnR/6ny6RjrlAbk2kK6/kicg== X-Received: by 2002:a05:6102:109:b0:452:5a95:16a with SMTP id z9-20020a056102010900b004525a95016amr6482433vsq.1.1696084559033; Sat, 30 Sep 2023 07:35:59 -0700 (PDT) Received: from majuu.waya ([174.93.66.252]) by smtp.gmail.com with ESMTPSA id vr25-20020a05620a55b900b0077434d0f06esm4466409qkn.52.2023.09.30.07.35.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 30 Sep 2023 07:35:58 -0700 (PDT) From: Jamal Hadi Salim To: netdev@vger.kernel.org Cc: deb.chatterjee@intel.com, anjali.singhai@intel.com, namrata.limaye@intel.com, tom@sipanda.io, mleitner@redhat.com, Mahesh.Shirshyad@amd.com, tomasz.osinski@intel.com, jiri@resnulli.us, xiyou.wangcong@gmail.com, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, vladbu@nvidia.com, horms@kernel.org, kernel@mojatatu.com, khalidm@nvidia.com, toke@redhat.com, mattyk@nvidia.com Subject: [PATCH RFC v6 net-next 05/17] net: sched: act_api: Add support for preallocated dynamic action instances Date: Sat, 30 Sep 2023 10:35:30 -0400 Message-Id: <20230930143542.101000-6-jhs@mojatatu.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230930143542.101000-1-jhs@mojatatu.com> References: <20230930143542.101000-1-jhs@mojatatu.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: kuba@kernel.org X-Patchwork-State: RFC In P4, actions are assumed to pre exist and have an upper bound number of instances. Typically if you have 1M table entries you want to allocate enough action instances to cover the 1M entries. However, this is a big waste of memory if the action instances are not in use. So for our case, we allow the user to specify a minimal amount of actions in the template and then if more dynamic action instances are needed then they will be added on demand as in the current approach with tc filter-action relationship. Add the necessary code to preallocate actions instances for dynamic actions. We add 2 new actions flags: - TCA_ACT_FLAGS_PREALLOC: Indicates the action instance is a dynamic action and was preallocated for future use the templating phase of P4TC - TCA_ACT_FLAGS_UNREFERENCED: Indicates the action instance was preallocated and is currently not being referenced by any other object. Which means it won't show up in an action instance dump. Once an action instance is created we don't free it when the last table entry referring to it is deleted. Instead we add it to the pool/cache of action instances for that specific action i.e it counts as if it is preallocated. Preallocated actions can't be deleted by the tc actions runtime commands and a dump or a get will only show preallocated actions instances which are being used (TCA_ACT_FLAGS_UNREFERENCED == false). The preallocated actions will be deleted once the pipeline is deleted (which will purge the dynamic action kind and its instances). For example, if we were to create a dynamic action that preallocates 128 elements and dumped: $ tc -j p4template get action/myprog/send_nh | jq . We'd see the following: [ { "obj": "action template", "pname": "myprog", "pipeid": 1 }, { "templates": [ { "aname": "myprog/send_nh", "actid": 1, "params": [ { "name": "port", "type": "dev", "id": 1 } ], "prealloc": 128 } ] } ] If we try to dump the dynamic action instances, we won't see any: $ tc -j actions ls action myprog/send_nh | jq . [] However, if we create a table entry which references this action kind: $ tc p4ctrl create myprog/table/cb/FDB \ dstAddr d2:96:91:5d:02:86 action myprog/send_nh \ param port type dev dummy0 Dumping the action instance will now show this one instance which is associated with the table entry: $ tc -j actions ls action myprog/send_nh | jq . [ { "total acts": 1 }, { "actions": [ { "order": 0, "kind": "myprog/send_nh", "index": 1, "ref": 1, "bind": 1, "params": [ { "name": "port", "type": "dev", "value": "dummy0", "id": 1 } ], "not_in_hw": true } ] } ] Co-developed-by: Victor Nogueira Signed-off-by: Victor Nogueira Co-developed-by: Pedro Tammela Signed-off-by: Pedro Tammela Signed-off-by: Jamal Hadi Salim --- include/net/act_api.h | 3 +++ net/sched/act_api.c | 50 ++++++++++++++++++++++++++++++++----------- 2 files changed, 41 insertions(+), 12 deletions(-) diff --git a/include/net/act_api.h b/include/net/act_api.h index 90e215f10..cd5a8e86f 100644 --- a/include/net/act_api.h +++ b/include/net/act_api.h @@ -68,6 +68,8 @@ struct tc_action { #define TCA_ACT_FLAGS_REPLACE (1U << (TCA_ACT_FLAGS_USER_BITS + 2)) #define TCA_ACT_FLAGS_NO_RTNL (1U << (TCA_ACT_FLAGS_USER_BITS + 3)) #define TCA_ACT_FLAGS_AT_INGRESS (1U << (TCA_ACT_FLAGS_USER_BITS + 4)) +#define TCA_ACT_FLAGS_PREALLOC (1U << (TCA_ACT_FLAGS_USER_BITS + 5)) +#define TCA_ACT_FLAGS_UNREFERENCED (1U << (TCA_ACT_FLAGS_USER_BITS + 6)) /* Update lastuse only if needed, to avoid dirtying a cache line. * We use a temp variable to avoid fetching jiffies twice. @@ -200,6 +202,7 @@ int tcf_idr_create_from_flags(struct tc_action_net *tn, u32 index, const struct tc_action_ops *ops, int bind, u32 flags); void tcf_idr_insert_many(struct tc_action *actions[]); +void tcf_idr_insert_n(struct tc_action *actions[], const u32 n); void tcf_idr_cleanup(struct tc_action_net *tn, u32 index); int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index, struct tc_action **a, int bind); diff --git a/net/sched/act_api.c b/net/sched/act_api.c index cfa74f521..6f4c29e90 100644 --- a/net/sched/act_api.c +++ b/net/sched/act_api.c @@ -560,6 +560,8 @@ static int tcf_dump_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb, continue; if (IS_ERR(p)) continue; + if (p->tcfa_flags & TCA_ACT_FLAGS_UNREFERENCED) + continue; if (jiffy_since && time_after(jiffy_since, @@ -640,6 +642,9 @@ static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb, idr_for_each_entry_ul(idr, p, tmp, id) { if (IS_ERR(p)) continue; + if (p->tcfa_flags & TCA_ACT_FLAGS_PREALLOC) + continue; + ret = tcf_idr_release_unsafe(p); if (ret == ACT_P_DELETED) module_put(ops->owner); @@ -1367,26 +1372,38 @@ static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = { [TCA_ACT_HW_STATS] = NLA_POLICY_BITFIELD32(TCA_ACT_HW_STATS_ANY), }; +static void tcf_idr_insert_1(struct tc_action *a) +{ + struct tcf_idrinfo *idrinfo; + + idrinfo = a->idrinfo; + mutex_lock(&idrinfo->lock); + /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc if + * it is just created, otherwise this is just a nop. + */ + idr_replace(&idrinfo->action_idr, a, a->tcfa_index); + mutex_unlock(&idrinfo->lock); +} + void tcf_idr_insert_many(struct tc_action *actions[]) { int i; for (i = 0; i < TCA_ACT_MAX_PRIO; i++) { - struct tc_action *a = actions[i]; - struct tcf_idrinfo *idrinfo; - - if (!a) + if (!actions[i]) continue; - idrinfo = a->idrinfo; - mutex_lock(&idrinfo->lock); - /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc if - * it is just created, otherwise this is just a nop. - */ - idr_replace(&idrinfo->action_idr, a, a->tcfa_index); - mutex_unlock(&idrinfo->lock); + tcf_idr_insert_1(actions[i]); } } +void tcf_idr_insert_n(struct tc_action *actions[], const u32 n) +{ + int i; + + for (i = 0; i < n; i++) + tcf_idr_insert_1(actions[i]); +} + struct tc_action_ops *tc_action_load_ops(struct net *net, struct nlattr *nla, bool police, bool rtnl_held, struct netlink_ext_ack *extack) @@ -2033,8 +2050,17 @@ tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n, ret = PTR_ERR(act); goto err; } - attr_size += tcf_action_fill_size(act); actions[i - 1] = act; + + if (event == RTM_DELACTION && + act->tcfa_flags & TCA_ACT_FLAGS_PREALLOC) { + ret = -EINVAL; + NL_SET_ERR_MSG_FMT(extack, + "Unable to delete preallocated action %s", + act->ops->kind); + goto err; + } + attr_size += tcf_action_fill_size(act); } attr_size = tcf_action_full_attrs_size(attr_size);