From patchwork Sun Jul 11 05:00:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tonghao Zhang X-Patchwork-Id: 12368981 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A9BDC07E96 for ; Sun, 11 Jul 2021 05:00:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 64C7161351 for ; Sun, 11 Jul 2021 05:00:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229726AbhGKFDC (ORCPT ); Sun, 11 Jul 2021 01:03:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59452 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229485AbhGKFDB (ORCPT ); Sun, 11 Jul 2021 01:03:01 -0400 Received: from mail-pg1-x52d.google.com (mail-pg1-x52d.google.com [IPv6:2607:f8b0:4864:20::52d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1064BC0613DD for ; Sat, 10 Jul 2021 22:00:15 -0700 (PDT) Received: by mail-pg1-x52d.google.com with SMTP id y17so14482098pgf.12 for ; Sat, 10 Jul 2021 22:00:15 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=B/YrxSl2tp9RWF+ZcjOCmhzeXts8i9KqtNHczK7Iknc=; b=VcUihxtBee+rfMhfi8PRjeiq3sp/jZxEMC+PMo86bHOchp/daCxFV2lByRxk3rDOwD Ys9cuFWXhQE0DM2TTNracGZjWfIAFfPHsloQO0eonqYVtTjrgE+eKu9u6sgc0T3orWWn HKG14Ipyi+TPvm5/X+pMhvSD7ZJR7ArJdAvFj5hDmYz0ESGRjqUf0zsw0TKRW/NbuA33 YqPGvVguGgEVKIWSY666mZim5C80vlrUjscceGCRwUiIC+Wt/ZsOXwPoRJ7S1GeZ2je/ Q1wTKeajIT7GJsi4ESBRuolNPxYNrfgUDW42wWe04WP8/1Vn0mlJzRm2nGICf5eH/q7H UnWQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=B/YrxSl2tp9RWF+ZcjOCmhzeXts8i9KqtNHczK7Iknc=; b=D4PKA6Y+q7LAea6y+N2x7RFgnr0tV0f+puBR2ab7CaEeyLVCzuADJBSYGqg3C+ItVX CuOi73fmQHK/leJMSpoqGVmamAqmYL0VORc6cum3Y2ISsVhScnQZbdgyat/cWU5MbNOi eEedvUdygPMDIOUiT0qxvk0fHc30wzqSTSJDSK3Bb9k3Yi7DNfHTrhIZvteVloYPZUgq eJ8hREzX3P0eBY8eJzT68vWbQlWrjHtNwo+Vr28Bduel6seYuKXhF1qZ4BM5kMIcNEaC qM/P/IYwKvdqAoA9OIpbBZdgVuNksyTfw9MuRKUFfqc+HcU0qXbf00T27MZQ+Av8uHDx lbzg== X-Gm-Message-State: AOAM5302FIkBinD2zSOlMNwfe4cCv+qse2mednhOFBmPsmHxBQN6lVwF IAeblnW9+2mxBsvn/2tGzio= X-Google-Smtp-Source: ABdhPJwLBa+JNnSNWLhH7GuUi3MOV8GOJPCLn5L5mdkCuRcfiI2/0lg20LAfJIFrSYpaCwew0llalA== X-Received: by 2002:a63:582:: with SMTP id 124mr46493859pgf.299.1625979614677; Sat, 10 Jul 2021 22:00:14 -0700 (PDT) Received: from localhost.localdomain ([111.204.182.99]) by smtp.gmail.com with ESMTPSA id u37sm11147448pfg.140.2021.07.10.22.00.11 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Sat, 10 Jul 2021 22:00:14 -0700 (PDT) From: xiangxia.m.yue@gmail.com To: xiyou.wangcong@gmail.com, jhs@mojatatu.com Cc: netdev@vger.kernel.org, Tonghao Zhang Subject: [net-next 1/2] qdisc: add tracepoint qdisc:qdisc_enqueue for enqueued SKBs Date: Sun, 11 Jul 2021 13:00:06 +0800 Message-Id: <20210711050007.1200-1-xiangxia.m.yue@gmail.com> X-Mailer: git-send-email 2.30.1 (Apple Git-130) MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Tonghao Zhang This tracepoint can work with qdisc:qdisc_dequeue to measure packets latency in qdisc queue. In some case, for example, if TX queues are stopped or frozen, sch_direct_xmit will invoke the dev_requeue_skb to requeue SKBs to qdisc->gso_skb, that may delay the SKBs in qdisc queue. With this patch, we can measure packets latency. Signed-off-by: Tonghao Zhang --- include/net/pkt_sched.h | 4 ++++ include/trace/events/qdisc.h | 32 ++++++++++++++++++++++++++++++++ net/core/dev.c | 4 ++-- net/sched/sch_generic.c | 11 +++++++++++ 4 files changed, 49 insertions(+), 2 deletions(-) diff --git a/include/net/pkt_sched.h b/include/net/pkt_sched.h index 6d7b12cba015..66411b4ff284 100644 --- a/include/net/pkt_sched.h +++ b/include/net/pkt_sched.h @@ -133,6 +133,10 @@ static inline void qdisc_run(struct Qdisc *q) } } +int qdisc_enqueue_skb(struct netdev_queue *txq, struct Qdisc *q, + struct sk_buff *skb, + struct sk_buff **to_free); + /* Calculate maximal size of packet seen by hard_start_xmit routine of this device. */ diff --git a/include/trace/events/qdisc.h b/include/trace/events/qdisc.h index 330d32d84485..b0e76237bb74 100644 --- a/include/trace/events/qdisc.h +++ b/include/trace/events/qdisc.h @@ -11,6 +11,38 @@ #include #include +TRACE_EVENT(qdisc_enqueue, + + TP_PROTO(struct Qdisc *qdisc, const struct netdev_queue *txq, + struct sk_buff *skb, int ret), + + TP_ARGS(qdisc, txq, skb, ret), + + TP_STRUCT__entry( + __field( struct Qdisc *, qdisc ) + __field(const struct netdev_queue *, txq ) + __field( void *, skbaddr ) + __field( int, ifindex ) + __field( u32, handle ) + __field( u32, parent ) + __field( int, ret ) + ), + + TP_fast_assign( + __entry->qdisc = qdisc; + __entry->txq = txq; + __entry->skbaddr = skb; + __entry->ifindex = txq->dev ? txq->dev->ifindex : 0; + __entry->handle = qdisc->handle; + __entry->parent = qdisc->parent; + __entry->ret = ret; + ), + + TP_printk("enqueue ifindex=%d qdisc handle=0x%X parent=0x%X skbaddr=%p ret=%d", + __entry->ifindex, __entry->handle, __entry->parent, + __entry->skbaddr, __entry->ret) +); + TRACE_EVENT(qdisc_dequeue, TP_PROTO(struct Qdisc *qdisc, const struct netdev_queue *txq, diff --git a/net/core/dev.c b/net/core/dev.c index 50531a2d0b20..78efac6b2e60 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3852,7 +3852,7 @@ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, qdisc_calculate_pkt_len(skb, q); if (q->flags & TCQ_F_NOLOCK) { - rc = q->enqueue(skb, q, &to_free) & NET_XMIT_MASK; + rc = qdisc_enqueue_skb(txq, q, skb, &to_free); if (likely(!netif_xmit_frozen_or_stopped(txq))) qdisc_run(q); @@ -3896,7 +3896,7 @@ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q, qdisc_run_end(q); rc = NET_XMIT_SUCCESS; } else { - rc = q->enqueue(skb, q, &to_free) & NET_XMIT_MASK; + rc = qdisc_enqueue_skb(txq, q, skb, &to_free); if (qdisc_run_begin(q)) { if (unlikely(contended)) { spin_unlock(&q->busylock); diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c index e9c0afc8becc..75605075178f 100644 --- a/net/sched/sch_generic.c +++ b/net/sched/sch_generic.c @@ -415,6 +415,17 @@ void __qdisc_run(struct Qdisc *q) } } +int qdisc_enqueue_skb(struct netdev_queue *txq, struct Qdisc *q, + struct sk_buff *skb, + struct sk_buff **to_free) +{ + int ret; + + ret = q->enqueue(skb, q, to_free) & NET_XMIT_MASK; + trace_qdisc_enqueue(q, txq, skb, ret); + return ret; +} + unsigned long dev_trans_start(struct net_device *dev) { unsigned long val, res;