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 smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 62CCAC6FD1F for ; Sun, 12 Mar 2023 10:25:22 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id B4EE24183D; Sun, 12 Mar 2023 10:25:21 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org B4EE24183D Authentication-Results: smtp4.osuosl.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=U254Ki+X X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Fbq-aR-dt5_j; Sun, 12 Mar 2023 10:25:20 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by smtp4.osuosl.org (Postfix) with ESMTPS id CF28F416E7; Sun, 12 Mar 2023 10:25:19 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org CF28F416E7 Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 83C01C0071; Sun, 12 Mar 2023 10:25:19 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [IPv6:2605:bc80:3010::137]) by lists.linuxfoundation.org (Postfix) with ESMTP id DAB56C0032 for ; Sun, 12 Mar 2023 10:25:18 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id A11274176C for ; Sun, 12 Mar 2023 10:25:18 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org A11274176C X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id QbXpbAWuCWh7 for ; Sun, 12 Mar 2023 10:25:16 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org 9B624416E7 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by smtp4.osuosl.org (Postfix) with ESMTPS id 9B624416E7 for ; Sun, 12 Mar 2023 10:25:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1678616715; 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=ZXkk+bo18qTgFk5moKFN7B92iiR/As5vddC+8S+S5ic=; b=U254Ki+XG53ZfwYzZ7fb9N01gIj6x/peDoMwXExTQsgN5RcaJ0Vw93vjQw+5WJzJ3+HSn6 2wuexTwXQRw4UEHpJNa+WHZ4ep0UNTs06+Tm/Q+utgJBz1rcE4GwUXRBzsccdfHsRqUVrs ShIfwO8m5a9LnJheEq9NNFfxfzOI9sU= Received: from mail-ed1-f71.google.com (mail-ed1-f71.google.com [209.85.208.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-549-FlJmaw5tOkqZrZa351vTEg-1; Sun, 12 Mar 2023 06:25:13 -0400 X-MC-Unique: FlJmaw5tOkqZrZa351vTEg-1 Received: by mail-ed1-f71.google.com with SMTP id e18-20020a056402191200b004fa702d64b3so3606236edz.23 for ; Sun, 12 Mar 2023 03:25:13 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1678616712; 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=ZXkk+bo18qTgFk5moKFN7B92iiR/As5vddC+8S+S5ic=; b=rq1rc6Cdk49SzRUPOA5RUZvlfXkavP9uAY8DuuT0hFNPWgL3WRETIxbgjLxPy+DQ36 KU4/Tq2ZF/27Tc5j/gen7ryNquV+V+NOHMgQS059Qrt4+mRrEFVaUmR2Pa3H6vSjNq9Y I0ZgbrfF9bZYBlzJHGQFmEsPCVHPWJVsHT5lwNp7LkTw/z1drEdX17lvgc5o1O6AW5Aj TzLO8sR6nVWdBR3BYmn16HQyQ3BjtKhNCfPS50rWbuGjS+7cylu6DVreQ9qWGS8SDP1Q HvlYoJnq8NCDljh/Qv8MZRAbD2ST/uVzVnRKbWUBXNg/aDMGxVxUbhYEwgtZN+QseHsE EOFA== X-Gm-Message-State: AO0yUKXNlI/3csq5zAApLKQXQmI1zep3EFOA9GzmxCwDeywotluCsRYq zUa0fFrEWB3ad9t0dlhfa5A5Tr5Lip7xh71Fi5eQmfzwzB/Fe4nYY4Q5I9GslCdohHRioAtYbXF ML38ay2bew2Ev0Qp3DjskbDtEBS6HHRyw/MCOd0fTUA== X-Received: by 2002:a17:907:6289:b0:91d:9745:407e with SMTP id nd9-20020a170907628900b0091d9745407emr7799652ejc.18.1678616712719; Sun, 12 Mar 2023 03:25:12 -0700 (PDT) X-Google-Smtp-Source: AK7set9Xk1f2bF7i87QqYQvVBuYhNLE0YiaA43XdMk6WHTfahjqThLHzPXP1hZuwBonoO6VHOspIHg== X-Received: by 2002:a17:907:6289:b0:91d:9745:407e with SMTP id nd9-20020a170907628900b0091d9745407emr7799634ejc.18.1678616712418; Sun, 12 Mar 2023 03:25:12 -0700 (PDT) Received: from redhat.com ([2a02:14f:1fb:4775:5c5c:4007:acc2:a326]) by smtp.gmail.com with ESMTPSA id du1-20020a17090772c100b00926a3155fd0sm454438ejc.98.2023.03.12.03.25.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 12 Mar 2023 03:25:11 -0700 (PDT) Date: Sun, 12 Mar 2023 06:25:06 -0400 From: "Michael S. Tsirkin" To: Eli Cohen Subject: Re: [PATCH 1/2] vdpa/mlx5: Make VIRTIO_NET_F_MRG_RXBUF off by default Message-ID: <20230312054559-mutt-send-email-mst@kernel.org> References: <20230312083920.2300028-1-elic@nvidia.com> <20230312083920.2300028-2-elic@nvidia.com> <20230312045717-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Disposition: inline Cc: perezma@redhat.com, virtualization@lists.linux-foundation.org, Eugenio Perez Martin , parav@mellanox.com X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" On Sun, Mar 12, 2023 at 11:10:25AM +0200, Eli Cohen wrote: > > On 12/03/2023 10:58, Michael S. Tsirkin wrote: > > On Sun, Mar 12, 2023 at 10:39:19AM +0200, Eli Cohen wrote: > > > One can still enable it when creating the vdpa device using vdpa tool by > > > providing features that include it. > > > > > > For example: > > > $ vdpa dev add name vdpa0 mgmtdev pci/0000:86:00.2 device_features 0x300cb982b > > > > > > Signed-off-by: Eli Cohen > > What's the reason to turn it off by default? It's generally a > > performance win isn't it? > It has negative impact on packet rate so we want to keep it off by default. Interesting. I feel this would benefit from a bit more analysis. Packet rate with dpdk? With linux? Is there a chance this will regress some workloads? VIRTIO_NET_F_MRG_RXBUF was designed to save memory, which is good for small tcp buffers. > > > > > --- > > > drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 ++ > > > 1 file changed, 2 insertions(+) > > > > > > diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c > > > index 4abc3a4ee515..3858ba1e8975 100644 > > > --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c > > > +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c > > > @@ -3154,6 +3154,8 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name, > > > return -EINVAL; > > > } > > > device_features &= add_config->device_features; > > > + } else { > > > + device_features &= ~BIT_ULL(VIRTIO_NET_F_MRG_RXBUF); > > > } > > > if (!(device_features & BIT_ULL(VIRTIO_F_VERSION_1) && > > > device_features & BIT_ULL(VIRTIO_F_ACCESS_PLATFORM))) { > > > -- > > > 2.38.1 _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization