From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id 67471A0613 for ; Thu, 26 Sep 2019 17:48:47 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 2C1403237; Thu, 26 Sep 2019 17:48:47 +0200 (CEST) Received: from dispatch1-us1.ppe-hosted.com (dispatch1-us1.ppe-hosted.com [67.231.154.164]) by dpdk.org (Postfix) with ESMTP id B185E2C57 for ; Thu, 26 Sep 2019 17:48:45 +0200 (CEST) X-Virus-Scanned: Proofpoint Essentials engine Received: from webmail.solarflare.com (uk.solarflare.com [193.34.186.16]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mx1-us3.ppe-hosted.com (PPE Hosted ESMTP Server) with ESMTPS id 112829C0059; Thu, 26 Sep 2019 15:48:44 +0000 (UTC) Received: from [192.168.38.17] (91.220.146.112) by ukex01.SolarFlarecom.com (10.17.10.4) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Thu, 26 Sep 2019 16:48:37 +0100 To: Ori Kam CC: "dev@dpdk.org" , "jingjing.wu@intel.com" , "stephen@networkplumber.org" , "wenzhuo.lu@intel.com" , "bernard.iremonger@intel.com" , Thomas Monjalon , "ferruh.yigit@intel.com" , Slava Ovsiienko References: <1569479349-36962-1-git-send-email-orika@mellanox.com> From: Andrew Rybchenko Message-ID: Date: Thu, 26 Sep 2019 18:48:22 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-GB X-Originating-IP: [91.220.146.112] X-ClientProxiedBy: ocex03.SolarFlarecom.com (10.20.40.36) To ukex01.SolarFlarecom.com (10.17.10.4) X-TM-AS-Product-Ver: SMEX-12.5.0.1300-8.5.1010-24934.003 X-TM-AS-Result: No-22.356600-8.000000-10 X-TMASE-MatchedRID: pS5owHKhBO3mLzc6AOD8DfHkpkyUphL9ekMgTOQbVFuZt08TfNy6ON4V yKV9HAY3b3zp7Fd+U6ddOsaQOyKqmkaLFcw9F5OfUFJbPlmBv8PmP4XGEn488Q0dBhor/KuTwOW nbwsz43J1dkOHjwzQSHk5w+l3wsE1wB10SpFwpjwRZz7NjbwI0kqAhuLHn5fEQW6eCaGxKwIAWI kVozTVKwaTUlC0TbWA4YDNIWcGOsnWQNtoKISeLI9Ha73XaFhEP8DCBJyxDJnHN9tnHHgXhFb8K 2l7VvRSBSuHQ7HM64tLpc6AgM5ZL0FzHGaCt9Jl0H8ihGEHNUePzv8sr7ayo1ddtl4yXVYP9KWr ++yBQKMyqo0DCUsIXdNSAQ9Iwyl4b8YiNEMbR7ASEYfcJF0pRcoioCrSMgeKpjfLp08U3/VC663 F8Drn+BiH7F9sR3YLeCcv2/o3nDvjF3loif3ojEAvdL4TzpZNp1Pjcaldww04XREg9Ki10x/bLD YkGYch7I1AVGSPbUCyRoa4j2WmwiFXb/D0c7S5UeavKZUnS5AiJN3aXuV/oSNGK7UC7ElMi38wO ddlOps08+Wg+T/5wMO9G/I9jBtvMQwHKalfMOH0hv/rD7WVZCl06rL9FnHsYtJaVJe/wLEoWHlk tzCpMicZNojJ1G2ht6xSkNhe8NiZMrhqeTBW6klR2DE0NRdaRiPTMMc/MmlTbQ95zRbWVu2pyVW YHO0O3UwJgnKc1S4xc7rYSSRkuzOsAO+2EKqEhrO2+pxhVk+PGXEebjsPOnIfMVdBLSnmpC22f9 8zCIPnzlXMYw4XMAGLeSok4rrZ/wnffsU7xJLEQdG7H66TyFKwAwReS6XbUlC29sED2GQ= X-TM-AS-User-Approved-Sender: Yes X-TM-AS-User-Blocked-Sender: No X-TMASE-Result: 10--22.356600-8.000000 X-TMASE-Version: SMEX-12.5.0.1300-8.5.1010-24934.003 X-MDID: 1569512925-J8LHU8apcscx Subject: Re: [dpdk-dev] [PATCH 00/13] add hairpin feature X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Hi Ori, On 9/26/19 6:22 PM, Ori Kam wrote: > Hi Andrew, > Thanks for your comments please see blow. > >> -----Original Message----- >> From: Andrew Rybchenko >> >> On 9/26/19 9:28 AM, Ori Kam wrote: >>> This patch set implements the hairpin feature. >>> The hairpin feature was introduced in RFC[1] >>> >>> The hairpin feature (different name can be forward) acts as "bump on the >> wire", >>> meaning that a packet that is received from the wire can be modified using >>> offloaded action and then sent back to the wire without application >> intervention >>> which save CPU cycles. >>> >>> The hairpin is the inverse function of loopback in which application >>> sends a packet then it is received again by the >>> application without being sent to the wire. >>> >>> The hairpin can be used by a number of different NVF, for example load >>> balancer, gateway and so on. >>> >>> As can be seen from the hairpin description, hairpin is basically RX queue >>> connected to TX queue. >> Is it just a pipe or RTE flow API rules required? >> If it is just a pipe, what about transformations which could be useful >> in this >> case (encaps/decaps, NAT etc)? How to achieve it? >> If it is not a pipe and flow API rules are required, why is peer information >> required? >> > RTE flow is required, and the peer information is needed in order to connect between the RX queue to the > TX queue. From application it simply set ingress RTE flow rule that has queue or RSS actions, > with queues that are hairpin queues. > It may be possible to have one RX connected to number of TX queues in order to distribute the sending. It looks like I start to understand. First, RTE flow does its job and redirects some packets to hairpin Rx queue(s). Then, connection of hairpin Rx queues to Tx queues does its job. What happens if an Rx queue is connected to many Tx queues? Are packets duplicated? >>> During the design phase I was thinking of two ways to implement this >>> feature the first one is adding a new rte flow action. and the second >>> one is create a special kind of queue. >>> >>> The advantages of using the queue approch: >>> 1. More control for the application. queue depth (the memory size that >>> should be used). >> But it inherits many parameters which are not really applicable to hairpin >> queues. If all parameters are applicable, it should be explained in the >> context of the hairpin queues. >> > Most if not all parameters can be applicable also for hairpin queue. > And the one that wasn’t for example mempool was removed. I would really like to understand meaning of each Rx/Tx queue configuration parameter for hairpin case. So, I hope to see it in the documentation. >>> 2. Enable QoS. QoS is normaly a parametr of queue, so in this approch it >>> will be easy to integrate with such system. >> Could you elaborate it. >> > I will try. > If you are asking about use cases, we can assume a cloud provider that has number > of customers each with different bandwidth. We can configure a Tx queue with higher > priority which will result in that this queue will get more bandwidth. > This is true also for hairpin and non-hairpin. > We are working on more detail API how to use it, but the HW can support it. OK, a bit abstract still, but makes sense. >>> 3. Native integression with the rte flow API. Just setting the target >>> queue/rss to hairpin queue, will result that the traffic will be routed >>> to the hairpin queue. >> It sounds like queues are not required for flow API at all. >> If the goal is to send traffic outside to specified physical port, >> just specify it as an flow API action. That's it. >> > This was one of the possible options, but like stated above we think that there is more meaning to look > at it as a queue, which will give the application better control, for example selecting which queues > to connect to which queues. If it would have been done as RTE flow action then the PMD will create the queues and > binding internally and the application will lose control. > >>> 4. Enable queue offloading. >> Which offloads are applicable to hairpin queues? >> > Vlan striping for example, and all of the rte flow actions that targets a queue. Can it be done with VLAN_POP action at RTE flow level? The question is why we need it here as Rx queue offload. Who will get and process stripped VLAN? I don't understand what do you mean by the rte flow actions here. Sorry, but I still think that many Rx and Tx offloads are not applicable. >>> Each hairpin Rxq can be connected Txq / number of Txqs which can belong to >> a >>> different ports assuming the PMD supports it. The same goes the other >>> way each hairpin Txq can be connected to one or more Rxqs. >>> This is the reason that both the Txq setup and Rxq setup are getting the >>> hairpin configuration structure. >>> >>> From PMD prespctive the number of Rxq/Txq is the total of standard >>> queues + hairpin queues. >>> >>> To configure hairpin queue the user should call >>> rte_eth_rx_hairpin_queue_setup / rte_eth_tx_hairpin_queue_setup insteed >>> of the normal queue setup functions. >>> >>> The hairpin queues are not part of the normal RSS functiosn. >>> >>> To use the queues the user simply create a flow that points to RSS/queue >>> actions that are hairpin queues. >>> The reason for selecting 2 new functions for hairpin queue setup are: >>> 1. avoid API break. >>> 2. avoid extra and unused parameters. >>> >>> >>> This series must be applied after series[2] >>> >>> [1] >> https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Finbox.dpd >> k.org%2Fdev%2F1565703468-55617-1-git-send-email- >> orika%40mellanox.com%2F&data=02%7C01%7Corika%40mellanox.com%7 >> C3f32608241834727763208d7427d9b85%7Ca652971c7d2e4d9ba6a4d149256f4 >> 61b%7C0%7C0%7C637050979561965175&sdata=M%2F9hfQxEeYx23oHeS >> AQlzJmeWtOzaL%2FhWNmCC7u3E9g%3D&reserved=0 >>> [2] >> https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Finbox.dpd >> k.org%2Fdev%2F1569398015-6027-1-git-send-email- >> viacheslavo%40mellanox.com%2F&data=02%7C01%7Corika%40mellanox. >> com%7C3f32608241834727763208d7427d9b85%7Ca652971c7d2e4d9ba6a4d1 >> 49256f461b%7C0%7C0%7C637050979561965175&sdata=MP8hZ81ZO6br >> RoGeUY5v4%2FMIlFAhzAzryH4NW0MmnTI%3D&reserved=0 >> >> [snip] > Thanks > Ori