From patchwork Fri May 18 09:14:16 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shahaf Shuler X-Patchwork-Id: 916155 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=openvswitch.org (client-ip=140.211.169.12; helo=mail.linuxfoundation.org; envelope-from=ovs-dev-bounces@openvswitch.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=mellanox.com Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 40nNGs161Qz9s2R for ; Fri, 18 May 2018 19:31:49 +1000 (AEST) Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 86962EEF; Fri, 18 May 2018 09:28:55 +0000 (UTC) X-Original-To: dev@openvswitch.org Delivered-To: ovs-dev@mail.linuxfoundation.org Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 4D88FEA3 for ; Fri, 18 May 2018 09:28:47 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mellanox.co.il (mail-il-dmz.mellanox.com [193.47.165.129]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id C17436DC for ; Fri, 18 May 2018 09:28:45 +0000 (UTC) Received: from Internal Mail-Server by MTLPINE1 (envelope-from shahafs@mellanox.com) with ESMTPS (AES256-SHA encrypted); 18 May 2018 12:16:19 +0300 Received: from unicorn01.mtl.labs.mlnx. (unicorn01.mtl.labs.mlnx [10.7.12.62]) by labmailer.mlnx (8.13.8/8.13.8) with ESMTP id w4I9EQRk004808; Fri, 18 May 2018 12:14:27 +0300 From: Shahaf Shuler To: fc@napatech.com, ian.stokes@intel.com Date: Fri, 18 May 2018 12:14:16 +0300 Message-Id: X-Mailer: git-send-email 2.12.0 In-Reply-To: References: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Cc: dev@openvswitch.org, simon.horman@netronome.com, fbl@redhat.com Subject: [ovs-dev] [PATCH v10 6/7] dpif-netdev: do hw flow offload in a thread X-BeenThere: ovs-dev@openvswitch.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: ovs-dev-bounces@openvswitch.org Errors-To: ovs-dev-bounces@openvswitch.org From: Yuanhan Liu Currently, the major trigger for hw flow offload is at upcall handling, which is actually in the datapath. Moreover, the hw offload installation and modification is not that lightweight. Meaning, if there are so many flows being added or modified frequently, it could stall the datapath, which could result to packet loss. To diminish that, all those flow operations will be recorded and appended to a list. A thread is then introduced to process this list (to do the real flow offloading put/del operations). This could leave the datapath as lightweight as possible. Signed-off-by: Yuanhan Liu Signed-off-by: Shahaf Shuler --- lib/dpif-netdev.c | 348 ++++++++++++++++++++++++++++++++++++------------- 1 file changed, 258 insertions(+), 90 deletions(-) diff --git a/lib/dpif-netdev.c b/lib/dpif-netdev.c index 4748f70fa..0343d0a71 100644 --- a/lib/dpif-netdev.c +++ b/lib/dpif-netdev.c @@ -348,6 +348,37 @@ enum rxq_cycles_counter_type { RXQ_N_CYCLES }; +enum { + DP_NETDEV_FLOW_OFFLOAD_OP_ADD, + DP_NETDEV_FLOW_OFFLOAD_OP_MOD, + DP_NETDEV_FLOW_OFFLOAD_OP_DEL, +}; + +struct dp_flow_offload_item { + struct dp_netdev_pmd_thread *pmd; + struct dp_netdev_flow *flow; + int op; + struct match match; + struct nlattr *actions; + size_t actions_len; + + struct ovs_list node; +}; + +struct dp_flow_offload { + struct ovs_mutex mutex; + struct ovs_list list; + pthread_cond_t cond; +}; + +static struct dp_flow_offload dp_flow_offload = { + .mutex = OVS_MUTEX_INITIALIZER, + .list = OVS_LIST_INITIALIZER(&dp_flow_offload.list), +}; + +static struct ovsthread_once offload_thread_once + = OVSTHREAD_ONCE_INITIALIZER; + #define XPS_TIMEOUT 500000LL /* In microseconds. */ /* Contained by struct dp_netdev_port's 'rxqs' member. */ @@ -727,6 +758,8 @@ static void emc_clear_entry(struct emc_entry *ce); static void dp_netdev_request_reconfigure(struct dp_netdev *dp); static inline bool pmd_perf_metrics_enabled(const struct dp_netdev_pmd_thread *pmd); +static void queue_netdev_flow_del(struct dp_netdev_pmd_thread *pmd, + struct dp_netdev_flow *flow); static void emc_cache_init(struct emc_cache *flow_cache) @@ -1957,13 +1990,11 @@ struct flow_mark { struct cmap megaflow_to_mark; struct cmap mark_to_flow; struct id_pool *pool; - struct ovs_mutex mutex; }; static struct flow_mark flow_mark = { .megaflow_to_mark = CMAP_INITIALIZER, .mark_to_flow = CMAP_INITIALIZER, - .mutex = OVS_MUTEX_INITIALIZER, }; static uint32_t @@ -2113,7 +2144,7 @@ flow_mark_flush(struct dp_netdev_pmd_thread *pmd) CMAP_FOR_EACH (flow, mark_node, &flow_mark.mark_to_flow) { if (flow->pmd_id == pmd->core_id) { - mark_to_flow_disassociate(pmd, flow); + queue_netdev_flow_del(pmd, flow); } } } @@ -2135,6 +2166,226 @@ mark_to_flow_find(const struct dp_netdev_pmd_thread *pmd, return NULL; } +static struct dp_flow_offload_item * +dp_netdev_alloc_flow_offload(struct dp_netdev_pmd_thread *pmd, + struct dp_netdev_flow *flow, + int op) +{ + struct dp_flow_offload_item *offload; + + offload = xzalloc(sizeof(*offload)); + offload->pmd = pmd; + offload->flow = flow; + offload->op = op; + + dp_netdev_flow_ref(flow); + dp_netdev_pmd_try_ref(pmd); + + return offload; +} + +static void +dp_netdev_free_flow_offload(struct dp_flow_offload_item *offload) +{ + dp_netdev_pmd_unref(offload->pmd); + dp_netdev_flow_unref(offload->flow); + + free(offload->actions); + free(offload); +} + +static void +dp_netdev_append_flow_offload(struct dp_flow_offload_item *offload) +{ + ovs_mutex_lock(&dp_flow_offload.mutex); + ovs_list_push_back(&dp_flow_offload.list, &offload->node); + xpthread_cond_signal(&dp_flow_offload.cond); + ovs_mutex_unlock(&dp_flow_offload.mutex); +} + +static int +dp_netdev_flow_offload_del(struct dp_flow_offload_item *offload) +{ + return mark_to_flow_disassociate(offload->pmd, offload->flow); +} + +/* + * There are two flow offload operations here: addition and modification. + * + * For flow addition, this function does: + * - allocate a new flow mark id + * - perform hardware flow offload + * - associate the flow mark with flow and mega flow + * + * For flow modification, both flow mark and the associations are still + * valid, thus only item 2 needed. + */ +static int +dp_netdev_flow_offload_put(struct dp_flow_offload_item *offload) +{ + struct dp_netdev_port *port; + struct dp_netdev_pmd_thread *pmd = offload->pmd; + struct dp_netdev_flow *flow = offload->flow; + odp_port_t in_port = flow->flow.in_port.odp_port; + bool modification = offload->op == DP_NETDEV_FLOW_OFFLOAD_OP_MOD; + struct offload_info info; + uint32_t mark; + int ret; + + if (flow->dead) { + return -1; + } + + if (modification) { + mark = flow->mark; + ovs_assert(mark != INVALID_FLOW_MARK); + } else { + /* + * If a mega flow has already been offloaded (from other PMD + * instances), do not offload it again. + */ + mark = megaflow_to_mark_find(&flow->mega_ufid); + if (mark != INVALID_FLOW_MARK) { + VLOG_DBG("Flow has already been offloaded with mark %u\n", mark); + if (flow->mark != INVALID_FLOW_MARK) { + ovs_assert(flow->mark == mark); + } else { + mark_to_flow_associate(mark, flow); + } + return 0; + } + + mark = flow_mark_alloc(); + if (mark == INVALID_FLOW_MARK) { + VLOG_ERR("Failed to allocate flow mark!\n"); + } + } + info.flow_mark = mark; + + ovs_mutex_lock(&pmd->dp->port_mutex); + port = dp_netdev_lookup_port(pmd->dp, in_port); + if (!port) { + ovs_mutex_unlock(&pmd->dp->port_mutex); + return -1; + } + ret = netdev_flow_put(port->netdev, &offload->match, + CONST_CAST(struct nlattr *, offload->actions), + offload->actions_len, &flow->mega_ufid, &info, + NULL); + ovs_mutex_unlock(&pmd->dp->port_mutex); + + if (ret) { + if (!modification) { + flow_mark_free(mark); + } else { + mark_to_flow_disassociate(pmd, flow); + } + return -1; + } + + if (!modification) { + megaflow_to_mark_associate(&flow->mega_ufid, mark); + mark_to_flow_associate(mark, flow); + } + + return 0; +} + +static void * +dp_netdev_flow_offload_main(void *data OVS_UNUSED) +{ + struct dp_flow_offload_item *offload; + struct ovs_list *list; + const char *op; + int ret; + + for (;;) { + ovs_mutex_lock(&dp_flow_offload.mutex); + if (ovs_list_is_empty(&dp_flow_offload.list)) { + ovsrcu_quiesce_start(); + ovs_mutex_cond_wait(&dp_flow_offload.cond, + &dp_flow_offload.mutex); + } + list = ovs_list_pop_front(&dp_flow_offload.list); + offload = CONTAINER_OF(list, struct dp_flow_offload_item, node); + ovs_mutex_unlock(&dp_flow_offload.mutex); + + switch (offload->op) { + case DP_NETDEV_FLOW_OFFLOAD_OP_ADD: + op = "add"; + ret = dp_netdev_flow_offload_put(offload); + break; + case DP_NETDEV_FLOW_OFFLOAD_OP_MOD: + op = "modify"; + ret = dp_netdev_flow_offload_put(offload); + break; + case DP_NETDEV_FLOW_OFFLOAD_OP_DEL: + op = "delete"; + ret = dp_netdev_flow_offload_del(offload); + break; + default: + OVS_NOT_REACHED(); + } + + VLOG_DBG("%s to %s netdev flow\n", + ret == 0 ? "succeed" : "failed", op); + dp_netdev_free_flow_offload(offload); + } + + return NULL; +} + +static void +queue_netdev_flow_del(struct dp_netdev_pmd_thread *pmd, + struct dp_netdev_flow *flow) +{ + struct dp_flow_offload_item *offload; + + if (ovsthread_once_start(&offload_thread_once)) { + xpthread_cond_init(&dp_flow_offload.cond, NULL); + ovs_thread_create("dp_netdev_flow_offload", + dp_netdev_flow_offload_main, NULL); + ovsthread_once_done(&offload_thread_once); + } + + offload = dp_netdev_alloc_flow_offload(pmd, flow, + DP_NETDEV_FLOW_OFFLOAD_OP_DEL); + dp_netdev_append_flow_offload(offload); +} + +static void +queue_netdev_flow_put(struct dp_netdev_pmd_thread *pmd, + struct dp_netdev_flow *flow, struct match *match, + const struct nlattr *actions, size_t actions_len) +{ + struct dp_flow_offload_item *offload; + int op; + + if (!netdev_is_flow_api_enabled()) { + return; + } + + if (ovsthread_once_start(&offload_thread_once)) { + xpthread_cond_init(&dp_flow_offload.cond, NULL); + ovs_thread_create("dp_netdev_flow_offload", + dp_netdev_flow_offload_main, NULL); + ovsthread_once_done(&offload_thread_once); + } + + if (flow->mark != INVALID_FLOW_MARK) { + op = DP_NETDEV_FLOW_OFFLOAD_OP_MOD; + } else { + op = DP_NETDEV_FLOW_OFFLOAD_OP_ADD; + } + offload = dp_netdev_alloc_flow_offload(pmd, flow, op); + offload->match = *match; + offload->actions = xmalloc(actions_len); + memcpy(offload->actions, actions, actions_len); + offload->actions_len = actions_len; + + dp_netdev_append_flow_offload(offload); +} + static void dp_netdev_pmd_remove_flow(struct dp_netdev_pmd_thread *pmd, struct dp_netdev_flow *flow) @@ -2149,7 +2400,7 @@ dp_netdev_pmd_remove_flow(struct dp_netdev_pmd_thread *pmd, dpcls_remove(cls, &flow->cr); cmap_remove(&pmd->flow_table, node, dp_netdev_flow_hash(&flow->ufid)); if (flow->mark != INVALID_FLOW_MARK) { - mark_to_flow_disassociate(pmd, flow); + queue_netdev_flow_del(pmd, flow); } flow->dead = true; @@ -2731,88 +2982,6 @@ out: return error; } -/* - * There are two flow offload operations here: addition and modification. - * - * For flow addition, this function does: - * - allocate a new flow mark id - * - perform hardware flow offload - * - associate the flow mark with flow and mega flow - * - * For flow modification, both flow mark and the associations are still - * valid, thus only item 2 needed. - */ -static void -try_netdev_flow_put(struct dp_netdev_pmd_thread *pmd, odp_port_t in_port, - struct dp_netdev_flow *flow, struct match *match, - const struct nlattr *actions, size_t actions_len) -{ - struct offload_info info; - struct dp_netdev_port *port; - bool modification = flow->mark != INVALID_FLOW_MARK; - const char *op = modification ? "modify" : "add"; - uint32_t mark; - int ret; - - ovs_mutex_lock(&flow_mark.mutex); - - if (modification) { - mark = flow->mark; - } else { - if (!netdev_is_flow_api_enabled()) { - goto out; - } - - /* - * If a mega flow has already been offloaded (from other PMD - * instances), do not offload it again. - */ - mark = megaflow_to_mark_find(&flow->mega_ufid); - if (mark != INVALID_FLOW_MARK) { - VLOG_DBG("Flow has already been offloaded with mark %u\n", mark); - mark_to_flow_associate(mark, flow); - goto out; - } - - mark = flow_mark_alloc(); - if (mark == INVALID_FLOW_MARK) { - VLOG_ERR("Failed to allocate flow mark!\n"); - goto out; - } - } - info.flow_mark = mark; - - ovs_mutex_lock(&pmd->dp->port_mutex); - port = dp_netdev_lookup_port(pmd->dp, in_port); - if (!port) { - ovs_mutex_unlock(&pmd->dp->port_mutex); - goto out; - } - ret = netdev_flow_put(port->netdev, match, - CONST_CAST(struct nlattr *, actions), - actions_len, &flow->mega_ufid, &info, NULL); - ovs_mutex_unlock(&pmd->dp->port_mutex); - - if (ret) { - VLOG_ERR("Failed to %s netdev flow with mark %u\n", op, mark); - if (!modification) { - flow_mark_free(mark); - } else { - mark_to_flow_disassociate(pmd, flow); - } - goto out; - } - - if (!modification) { - megaflow_to_mark_associate(&flow->mega_ufid, mark); - mark_to_flow_associate(mark, flow); - } - VLOG_DBG("Succeed to %s netdev flow with mark %u\n", op, mark); - -out: - ovs_mutex_unlock(&flow_mark.mutex); -} - static void dp_netdev_get_mega_ufid(const struct match *match, ovs_u128 *mega_ufid) { @@ -2878,7 +3047,7 @@ dp_netdev_flow_add(struct dp_netdev_pmd_thread *pmd, cmap_insert(&pmd->flow_table, CONST_CAST(struct cmap_node *, &flow->node), dp_netdev_flow_hash(&flow->ufid)); - try_netdev_flow_put(pmd, in_port, flow, match, actions, actions_len); + queue_netdev_flow_put(pmd, flow, match, actions, actions_len); if (OVS_UNLIKELY(!VLOG_DROP_DBG((&upcall_rl)))) { struct ds ds = DS_EMPTY_INITIALIZER; @@ -2960,7 +3129,6 @@ flow_put_on_pmd(struct dp_netdev_pmd_thread *pmd, if (put->flags & DPIF_FP_MODIFY) { struct dp_netdev_actions *new_actions; struct dp_netdev_actions *old_actions; - odp_port_t in_port = netdev_flow->flow.in_port.odp_port; new_actions = dp_netdev_actions_create(put->actions, put->actions_len); @@ -2968,8 +3136,8 @@ flow_put_on_pmd(struct dp_netdev_pmd_thread *pmd, old_actions = dp_netdev_flow_get_actions(netdev_flow); ovsrcu_set(&netdev_flow->actions, new_actions); - try_netdev_flow_put(pmd, in_port, netdev_flow, match, - put->actions, put->actions_len); + queue_netdev_flow_put(pmd, netdev_flow, match, + put->actions, put->actions_len); if (stats) { get_dpif_flow_stats(netdev_flow, stats);