From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga14.intel.com ([192.55.52.115]:64700 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725828AbgFCKwm (ORCPT ); Wed, 3 Jun 2020 06:52:42 -0400 Date: Wed, 3 Jun 2020 12:48:33 +0200 From: Maciej Fijalkowski Subject: Re: XDP_REDIRECT with xsks_map and dev_map Message-ID: <20200603104833.GA14391@ranger.igk.intel.com> References: <87d06hzvr8.fsf@toke.dk> <877dwpmp7f.fsf@toke.dk> <87lfl4l8zu.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <87lfl4l8zu.fsf@toke.dk> Sender: xdp-newbies-owner@vger.kernel.org List-ID: To: Toke =?iso-8859-1?Q?H=F8iland-J=F8rgensen?= Cc: maharishi bhargava , xdp-newbies@vger.kernel.org On Wed, Jun 03, 2020 at 12:49:25PM +0200, Toke Høiland-Jørgensen wrote: > maharishi bhargava writes: > > > On Tue, Jun 2, 2020 at 9:31 PM Toke Høiland-Jørgensen wrote: > >> > >> maharishi bhargava writes: > >> > >> > On Tue 2 Jun, 2020, 14:31 Toke Høiland-Jørgensen, wrote: > >> >> > >> >> maharishi bhargava writes: > >> >> > >> >> > Hi, in my XDP program, I want to redirect some packets using AF_XDP > >> >> > and redirect other packets directly from driver space. > >> >> > Redirection through AF_XDP works fine, but redirection through dev map > >> >> > stops after some packets are processed. > >> >> > >> >> Do you mean it stops even if you are *only* redirecting to a devmap, or > >> >> if you are first redirecting a few packets to AF_XDP, then to devmap? > >> >> > >> >> Also, which driver(s) are the physical NICs you're redirecting to/from > >> >> using, and which kernel version are you on? > >> >> > >> >> -Toke > >> > > >> > > >> > > >> > Currently, I'm trying to redirect packets only using devmap. But also > >> > have code for redirection using AF_XDP(only when a given condition is > >> > satisfied). A DPDK program is running in userspace which will receive > >> > packets from AF_XDP. > >> > >> Right, so it's just devmap redirect that breaks. What do you mean > >> 'redirection stops', exactly? How are you seeing this? Does xdp_monitor > >> (from samples/bpf) report any exceptions? > >> > >> -Toke > >> > > So, In my setup, there are three systems, Let's Assume A, B, C. System > > B is acting as a forwarder between A and C. So I can see the number of > > packets received at system C. To be specific, only 1024 packets are > > received. If I remove the xsks_map part from the code and don't run > > DPDK in userspace. This problem does not occur. Also if I forward all > > the packets using AF_XDP, there is no such issue. > > I thought you said you were seeing the problem when only redirecting to > a devmap? So why does the xsk_map code impact this? I think you may have > to share some code... Isn't the case here that either xsk_map or dev_map consumes the frame and therefore the latter doesn't see it? so cloning might be needed here? > > Also, what does xdp_monitor say? > > -Toke >