From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 07E9BC433F5 for ; Wed, 1 Dec 2021 22:35:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353629AbhLAWjS (ORCPT ); Wed, 1 Dec 2021 17:39:18 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46298 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1353606AbhLAWjP (ORCPT ); Wed, 1 Dec 2021 17:39:15 -0500 Received: from mail-oo1-xc34.google.com (mail-oo1-xc34.google.com [IPv6:2607:f8b0:4864:20::c34]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 515B6C061574; Wed, 1 Dec 2021 14:35:54 -0800 (PST) Received: by mail-oo1-xc34.google.com with SMTP id p2-20020a4adfc2000000b002c2676904fdso8274583ood.13; Wed, 01 Dec 2021 14:35:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=aR6nqdM/vydgq6qDfEEr9BeTcrpq85WJhoLFzTKF01M=; b=RcUbS1boQiYqSykhzAsqltKp+aHjFfaKdIydgFxEoyskq29KoB0wm4pEkUFgLp5Wwh /PbHfQpjwZesa2NPKMLdKjtLAnoqmfXKFsB77s4ybwBuBaR78NeoAxj+DZ+57ygp1Yt6 TABoebiwraKNfoTRK30+j8sXLA/uVeQzm6pi0VKDWRpFE2urbEoZT71XMWJ98oYk50Ae pn13DQKE32SGrUHscqux1h7x8siLb59MS7wdwCOIdFb71feMyG0CjCvG+sspJzffrKGP xWmyf7gcaAZNMvslj3zxJxPwV7zfxb1+dZuGxZmRGSNE8QUpLfruClQKqZ3cHo+mQwmF QSwQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=aR6nqdM/vydgq6qDfEEr9BeTcrpq85WJhoLFzTKF01M=; b=YEY8QPFZmTp4lb4lgi6E/3GZeBe/9qfu84t49m7UtzlZ3GP7d7lkVL9JSsC4Yrs4jf kSbjACl7qmXfVAw165nTye7FnwK8RH/Hj4nClEpA1MNMa9wZqxkDEQex7psc5QXlPVdg UEkL2F8TmXtW/UsZO47OPYM07ppcA5mSIfqhPQwQTFAr+NK1VJh65wc3Qf7kODNjkrl1 F6b49b/LDEYQWNefSGdv7tPcccGg9qKYX5Z887J9AnnKTykA+1Dvv1NArL3I6Wt+KBEx G/qieV6/FpUkhPeR+7mV04RiwQj5JesIHyzDJkSJkzH6mbgzr9Xcv+sW0Ck3p8a7qzvh PajA== X-Gm-Message-State: AOAM532SNTdDqE7z0qhx9pa8OLy2apUEYnSZl3RtHJFPWrcnq9huA/Jm Ba69tJOcvcUNcYb1bg6QIi0= X-Google-Smtp-Source: ABdhPJxZz2rIE36CCv540gJdfz2xnJhbK3KScVA2690elpnzWMQmFM2+1TF0I9dSWDib52/BRbkjFA== X-Received: by 2002:a4a:c890:: with SMTP id t16mr6186170ooq.95.1638398153705; Wed, 01 Dec 2021 14:35:53 -0800 (PST) Received: from [172.16.0.2] ([8.48.134.30]) by smtp.googlemail.com with ESMTPSA id l27sm439576ota.26.2021.12.01.14.35.52 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 01 Dec 2021 14:35:53 -0800 (PST) Message-ID: <66dc5bcb-633d-efe8-0ccc-dcb97d08769c@gmail.com> Date: Wed, 1 Dec 2021 15:35:49 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.3.1 Subject: Re: [RFC 00/12] io_uring zerocopy send Content-Language: en-US To: Martin KaFai Lau , Pavel Begunkov Cc: io-uring@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jakub Kicinski , Jonathan Lemon , "David S . Miller" , Willem de Bruijn , Eric Dumazet , Hideaki YOSHIFUJI , David Ahern , Jens Axboe References: <994e315b-fdb7-1467-553e-290d4434d853@gmail.com> <889c0306-afed-62cd-d95b-a20b8e798979@gmail.com> <0b92f046-5ac3-7138-2775-59fadee6e17a@gmail.com> <974b266e-d224-97da-708f-c4a7e7050190@gmail.com> <20211201215157.kgqd5attj3dytfgs@kafai-mbp.dhcp.thefacebook.com> From: David Ahern In-Reply-To: <20211201215157.kgqd5attj3dytfgs@kafai-mbp.dhcp.thefacebook.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 12/1/21 2:51 PM, Martin KaFai Lau wrote: > > To tx out dummy, I did: > #> ip a add 10.0.0.1/24 dev dummy0 ^^^^^^^^ > > #> ip -4 r > 10.0.0.0/24 dev dummy0 proto kernel scope link src 10.0.0.1 > > #> ./send-zc -4 -D 10.0.0.(2) -t 10 udp ^^^^^^^^^^ Pavel's commands have: 'send-zc -4 -D -t 10 udp' I read dummy_ip_addr as the address assigned to dummy0; that's an important detail. You are sending to an address on that network, not the address assigned to the device, in which case packets are created and then dropped by the dummy driver - nothing actually makes it to the server. > ip -s link show dev dummy0 > 2: dummy0: mtu 65535 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000 > link/ether 82:0f:e0:dc:f7:e6 brd ff:ff:ff:ff:ff:ff > RX: bytes packets errors dropped missed mcast > 0 0 0 0 0 0 > TX: bytes packets errors dropped carrier collsns > 140800890299 2150397 0 0 0 0 >