From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bruce Richardson Subject: Re: Using multi-queue with RSS on X540 VF Date: Mon, 15 Dec 2014 10:52:41 +0000 Message-ID: <20141215105240.GB11332@bricha3-MOBL3> References: <20141215104739.GA11332@bricha3-MOBL3> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Cc: "dev-VfR2kkLFssw@public.gmane.org" To: Anant Mudambi Return-path: Content-Disposition: inline In-Reply-To: <20141215104739.GA11332@bricha3-MOBL3> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces-VfR2kkLFssw@public.gmane.org Sender: "dev" On Mon, Dec 15, 2014 at 10:47:40AM +0000, Bruce Richardson wrote: > On Sat, Dec 13, 2014 at 01:44:36AM +0000, Anant Mudambi wrote: > > Hi all, > > I am using DPDK 1.7.0. > > Qemu-KVM system with the Intel 10G X540 NIC; host has the Linux ixgbe= PF driver and a guest is using a VF with the DPDK ixgbevf PMD (uio). > > I am trying to configure multiple (2 for now) receive queues on the V= F and use RSS. > > I see packets coming only to queue 0 for some reason. Some questions = about this: > >=20 > > 1] I see that most of the initial configuration to make multi-queue += RSS work is done in ixgbe_dev_mq_rx_configure() > > [e.g. Setting up the redirect table and the MRQC register]. Howe= ver, only the non-VF ixgbe_dev_rx_init() calls the above function; > > ixgbevf_dev_rx_init() doesn't configure RSS-related hardware. Do= n't we need to do this configuration to use RSS on a VF? > > 2] Even after configuring the RSS-related hardware in ixgbevf PMD, pa= ckets only come to queue 0. I printed out the RSS-type and RSS-hash-value > > fields from the write back Rx descriptor and they are both set t= o 0. So for some reason no RSS hash is being done for any packets. > > 3] Has anyone seen this kind of configuration work (multi-queue + RSS= + VF)? I have an X540 NIC but has this worked on any other NIC for anyon= e? > > 4] Also any ideas on how to debug this problem further? > >=20 > > Thanks, > > Anant >=20 > RSS redirection of traffic in a VF is not supported by the hardware, so= you are > pretty much stuck with all VF traffic going to queue 0. [Later hardware= , such as > 4x10G NICs e.g. "Intel=AE Ethernet Converged Network Adapters XL710" us= ing the > i40e driver should support RSS with VFs] >=20 > /Bruce Actually, I see Changchun has posted a patch giving support for RSS use w= ith VF's so apparently some functionality is possible with 10G NICs such as the x5= 40. There may be some limitations with it, however, but I'll defer any further expl= anation to him. :-) /Bruce