From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 77F6A436F7; Fri, 15 Dec 2023 05:58:20 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 48F8D402A6; Fri, 15 Dec 2023 05:58:20 +0100 (CET) Received: from mail-yw1-f176.google.com (mail-yw1-f176.google.com [209.85.128.176]) by mails.dpdk.org (Postfix) with ESMTP id 3B494402A6 for ; Fri, 15 Dec 2023 05:58:18 +0100 (CET) Received: by mail-yw1-f176.google.com with SMTP id 00721157ae682-5d7a47d06eeso2129507b3.1 for ; Thu, 14 Dec 2023 20:58:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1702616297; x=1703221097; darn=dpdk.org; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=7/vysXNxqJ9Q/C3SVYhm/KYBTj0phEiepJpfsqpmtKY=; b=ldIoqKrKCGzFz9+wSQZ079GSsACHTmon3BL6dfNAaMepyZiH/7vykFh9FQ3DfTEOMJ 9c5uz5NBTHt/YkN3f5UokTpb5jl+BzYZjeMz6p7UvaAA+0sHF4LJYv2Tq6vcpPz7nRiK gdirWkB41sb1xsi/SRjxKJJ6UulWEe0TAPtvKGN6rQXkL0qzwGbnwVVJQkBw8lXXp2nl B22WRG26MxpPbhj4zKZjJSAFrmsn3DKf5mtXIXxjzFAucXsRqMQnC/8tuuyeLhN2aLJ9 Jfyp/4d7KVj57Z3gNn7gatDQYKpzl6Y5sDa639sfDEXUCoMKW/pwMQUpjSU7sHB7VaC0 J0Bw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702616297; x=1703221097; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=7/vysXNxqJ9Q/C3SVYhm/KYBTj0phEiepJpfsqpmtKY=; b=M02jbpx3BT4YjGIWsKtNz/3OGyV83rKCa7vyJR+UyNbP5IdVmnMOF4hRqi4h10IXm6 /mQIQCCOE/Y/6nVmHcbY8tBsk+benmvDGQpwA079VCvABQxX7SfhiolFoOQCDYTaHVq9 UodfWHvjt0qPJOXlEzCw8hadrOBhPDv/2BuOR4DDY/P1+CErDdP/KbldFwy7aG60eMyI 6Mu4AA06dN4Xd9lfsk0J3AeDk0AuYHgQH/HsyY50XR7qbfZSa+HqoiLjyZohY6/2VUR0 UJxYNfPg8+6G8oMdfl+SipQW7LcB6Dq9qtQk6FIs016P0rUW67X0o5yrGzBzAVtolCtN G+5Q== X-Gm-Message-State: AOJu0YxuxTGIziWI7vx3Z6uFZ2KoxLwCZENmrOTqZX4BQj4q07Hl/Gt6 3ZtOmwhgGzFogxARUhdAQymoTz4EVjgijLyegZAxirEl X-Google-Smtp-Source: AGHT+IE4iWZn0E0XvFNcA35ceaAWoC4sHOaa3icpHuqTwx6wRxY/8lqAO4qAdL7X+1oKlzjdNEhT9m8Tma4xVVGSNh8= X-Received: by 2002:a5b:787:0:b0:d9a:66a1:a957 with SMTP id b7-20020a5b0787000000b00d9a66a1a957mr7813898ybq.13.1702616297345; Thu, 14 Dec 2023 20:58:17 -0800 (PST) MIME-Version: 1.0 References: <20231214174951.8317-1-stephen@networkplumber.org> <20231214190119.7bb28203@hermes.local> In-Reply-To: <20231214190119.7bb28203@hermes.local> From: kumaraparameshwaran rathinavel Date: Fri, 15 Dec 2023 10:28:06 +0530 Message-ID: Subject: Re: [PATCH] net/tap: add deprecation notice for RTE_FLOW_ACTION_RSS To: Stephen Hemminger Cc: dev Content-Type: multipart/alternative; boundary="000000000000979702060c853f02" X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org --000000000000979702060c853f02 Content-Type: text/plain; charset="UTF-8" On Fri, Dec 15, 2023, 8:31 AM Stephen Hemminger wrote: > On Fri, 15 Dec 2023 00:18:41 +0530 > kumaraparameshwaran rathinavel wrote: > > > On Thu, Dec 14, 2023, 11:20 PM Stephen Hemminger < > stephen@networkplumber.org> > > wrote: > > > > > The BPF infrastructure in kernel changed which broke the method > > > being used to load the RSS part of rte_flow in the TAP device. > > > Since this is a little used feature, and fixing the problem would > > > be moderately complex and create new dependency on libbpf, > > > mark the feature as deprecated and plan for removal. > > > > Does this mean that RSS will not work with netvsc as netvsc is using > > tap and mellanox ? Or will that not be affected . > > > The netvsc driver does not support rte_flow because the packets arrive > direct from host (over vmbus). It does have normal RSS. > It many ways netvsc is equivalent in functionality to virtio and vmxnet3. > > The tap BPF stuff was only useful for doing flow steering to a set of > queues. It was a hack to get the kernel to do flow steering. > Sure. I wanted to mean that the failsafe PMD that uses tap and mellanox relies on offloads of both the devices. So will this cause failsafe PMD to not use RSS and hence some performance impact ? > --000000000000979702060c853f02 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable


On Fri, Dec 15, 2023, 8:31 AM Stephen Hemminger <stephen@networkplumber.org&= gt; wrote:
On Fri, 15 Dec 2023 00:1= 8:41 +0530
kumaraparameshwaran rathinavel <kumaraparamesh92@gmail.com&g= t; wrote:

> On Thu, Dec 14, 2023, 11:20 PM Stephen Hemminger <stephen@n= etworkplumber.org>
> wrote:
>
> > The BPF infrastructure in kernel changed which broke the method > > being used to load the RSS part of rte_flow in the TAP device. > > Since this is a little used feature, and fixing the problem would=
> > be moderately complex and create new dependency on libbpf,
> > mark the feature as deprecated and plan for removal.=C2=A0
>
>=C2=A0 =C2=A0 =C2=A0Does this mean that RSS will not work with netvsc a= s netvsc is using
> tap and mellanox ? Or will that not be affected .


The netvsc driver does not support rte_flow because the packets arrive
direct from host (over vmbus). It does have normal RSS.
It many ways netvsc is equivalent in functionality to virtio and vmxnet3.
The tap BPF stuff was only useful for doing flow steering to a set of
queues. It was a hack to get the kernel to do flow steering.

Sure. I wanted = to mean that the failsafe PMD that uses tap and mellanox=C2=A0 relies on of= floads of both the devices. So=C2=A0 will this cause failsafe PMD to not us= e RSS and hence some performance impact ?=C2=A0
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