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 0A71DC77B73 for ; Tue, 25 Apr 2023 14:19:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234391AbjDYOSp (ORCPT ); Tue, 25 Apr 2023 10:18:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35182 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234246AbjDYOSn (ORCPT ); Tue, 25 Apr 2023 10:18:43 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B5F481447E for ; Tue, 25 Apr 2023 07:17:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1682432181; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=thZWYLLZcDX55mVu1+A52YHxk2dw+nbxOfZf7i61JuY=; b=V7kicDwjARzT6r5iFaUDwLMAKR2RcYB6XEfS9QuL0Ju/+hj0Y4loBWY77OyHPpJbAM0s3F ZCuBKUXH9rxvf5PNvkMbs0cPjPOA3hi9a1CPS1/Mb2ROz4YXid3xAFHX3mx/+eWm1OdjU2 RM5P/XAlSnDR6a2P9z5X07dD+yuCaNA= Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-483--GRGODr6OyOx_SB81BePLg-1; Tue, 25 Apr 2023 10:13:12 -0400 X-MC-Unique: -GRGODr6OyOx_SB81BePLg-1 Received: by mail-wm1-f71.google.com with SMTP id 5b1f17b1804b1-3f065208a64so33891545e9.3 for ; Tue, 25 Apr 2023 07:13:10 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1682431989; x=1685023989; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=thZWYLLZcDX55mVu1+A52YHxk2dw+nbxOfZf7i61JuY=; b=URhNAhXSRKQO/JHtnbC+tx0I+LJJV1X0DwcLKGMM2MfJ9bsL+ary4wTFKmVfkpv8uO v7LIWsDgoFSxZt3kXqUvSmdNCqbw5S0HP5HpfQJrgCCWVjGPphMFKmoQ1Y8Vm/dtRH9k 0upJep9AaZY66yTonZAntp4hteUcgCh/XuWQ00V1B05rmJC1VNCu/xK1HQBEVCqCMb3h Z5bVsPaEuLtyM9Pp/hFNdAP13ssVxlZNBFzgMRHCFCx7ktB0KQeOqUADbq+PPBxigjhQ aokHlIEoF3lI8ZxL8xfQ3fb2eDrCnNhR5ELRATaLkrjwhSJA9sbwmxyNwaMexZjwo9GH qarA== X-Gm-Message-State: AAQBX9d8fkm1JiHlFkxXgFuIhd6RxdqwO4XqSFM3uq3qMQBP2USkTOwI uefGcsLjm02eUgzBkwR/KNPscRYbTguqKxEthhrkj0xKKWZVqH9K2Hw332Q0abq2qQhjcGccsc0 xuZD2z7QttQKllDWR X-Received: by 2002:a1c:ed01:0:b0:3f1:7b8d:38ec with SMTP id l1-20020a1ced01000000b003f17b8d38ecmr10305880wmh.35.1682431989730; Tue, 25 Apr 2023 07:13:09 -0700 (PDT) X-Google-Smtp-Source: AKy350bJGY+FZC43FdCJjTRL7XkjQU2DBR+cD6qqUiqenfVzDuWXgnT/+wvkpBSWPa/aO83OrDN9FA== X-Received: by 2002:a1c:ed01:0:b0:3f1:7b8d:38ec with SMTP id l1-20020a1ced01000000b003f17b8d38ecmr10305856wmh.35.1682431989391; Tue, 25 Apr 2023 07:13:09 -0700 (PDT) Received: from localhost (net-130-25-106-149.cust.vodafonedsl.it. [130.25.106.149]) by smtp.gmail.com with ESMTPSA id c21-20020a7bc855000000b003f17300c7dcsm15023553wml.48.2023.04.25.07.13.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Apr 2023 07:13:08 -0700 (PDT) Date: Tue, 25 Apr 2023 16:13:07 +0200 From: Lorenzo Bianconi To: Yunsheng Lin Cc: Maciej Fijalkowski , Lorenzo Bianconi , netdev@vger.kernel.org, bpf@vger.kernel.org, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, hawk@kernel.org, john.fastabend@gmail.com, ast@kernel.org, daniel@iogearbox.net Subject: Re: [PATCH v2 net-next 1/2] net: veth: add page_pool for page recycling Message-ID: References: <6298f73f7cc7391c7c4a52a6a89b1ae21488bda1.1682188837.git.lorenzo@kernel.org> <4f008243-49d0-77aa-0e7f-d20be3a68f3c@huawei.com> <3c78f045-aa8e-22a5-4b38-ab271122a79e@huawei.com> <0c1790dc-dbeb-8664-64ca-1f71e6c4f3a9@huawei.com> <99890c72-eb61-e032-944a-6671d6494c23@huawei.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="CadSs8zlJcx9K3kf" Content-Disposition: inline In-Reply-To: <99890c72-eb61-e032-944a-6671d6494c23@huawei.com> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org --CadSs8zlJcx9K3kf Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > On 2023/4/24 21:10, Maciej Fijalkowski wrote: > >>> There was a discussion in the past to reduce XDP_PACKET_HEADROOM to 1= 92B but > >>> this is not merged yet and it is not related to this series. We can a= ddress > >>> your comments in a follow-up patch when XDP_PACKET_HEADROOM series is= merged. > >=20 > > Intel drivers still work just fine at 192 headroom and split the page b= ut > > it makes it problematic for BIG TCP where MAX_SKB_FRAGS from shinfo nee= ds >=20 > I am not sure why we are not enabling skb_shinfo(skb)->frag_list to suppo= rt > BIG TCP instead of increasing MAX_SKB_FRAGS, perhaps there was some dissc= ution > about this in the past I am not aware of? >=20 > > to be increased. So it's the tailroom that becomes the bottleneck, not = the > > headroom. I believe at some point we will convert our drivers to page_p= ool > > with full 4k page dedicated for a single frame. >=20 > Can we use header splitting to ensure there is enough tailroom for > napi_build_skb() or xdp_frame with shinfo? >=20 since veth_convert_skb_to_xdp_buff() runs in veth_poll() I think we can use napi_build_skb(). I tested it and we get an improvement (9.65Gbps vs 9.2Gbps for 1500B frames). Regards, Lorenzo --CadSs8zlJcx9K3kf Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTquNwa3Txd3rGGn7Y6cBh0uS2trAUCZEff8gAKCRA6cBh0uS2t rMbdAQD3WHQe/mjpUtHWLC7RlTGjjTZB2VrCKz6tldyN9wIguQEAsjoeLh830e8k AGbqbbOerSm9+RznSSmS08hoTh5VLQ8= =njoc -----END PGP SIGNATURE----- --CadSs8zlJcx9K3kf--