From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: <dev-bounces@dpdk.org> Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 6BF23A054F; Mon, 15 Mar 2021 20:49:00 +0100 (CET) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 5691F2427C3; Mon, 15 Mar 2021 20:49:00 +0100 (CET) Received: from office2.cesnet.cz (office2.cesnet.cz [195.113.144.244]) by mails.dpdk.org (Postfix) with ESMTP id 6D0D74069F for <dev@dpdk.org>; Mon, 15 Mar 2021 20:48:58 +0100 (CET) Received: from tanguero.localdomain (unknown [95.82.133.55]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by office2.cesnet.cz (Postfix) with ESMTPSA id 2ECAF400052; Mon, 15 Mar 2021 20:48:58 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cesnet.cz; s=office2-2020; t=1615837738; bh=ygwYPTMAN80PwGFQZxcH0gsGkPXEQfzjsitC8pu8s3k=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=CktUrZUAhlmb89/1EQR6QRaqwRTVz9uAJTjRRd39XgTwINXflOrHJTkeuaRG8VQJB 28YujVQubchjewB0MYlVMJ5xJbrOFrQDve/U5w3VRCcorycLjp9Lbp2dJvj/eUStAP ZZT8tnsKTRK7iZBwFwiVj082rLCALoIlsZs7cf/jPNnjGYFmVHCaMMsgD2kbPmoBTN iRJyZhIJgZfX5qJhl3P3VpunqDQ2hnu3inGh5eavrhih3r+25rfswcoMPe7P8bdgwC Sq07obg90PakggKQB6x/igGcrBZGeETyaS31NC2wSz42q6mTiIpchGxTYmrGld4kHh NwRIXrouprpVA== Date: Mon, 15 Mar 2021 20:48:56 +0100 From: Jan Viktorin <viktorin@cesnet.cz> To: Slava Ovsiienko <viacheslavo@nvidia.com> Cc: "dev@dpdk.org" <dev@dpdk.org>, Asaf Penso <asafp@nvidia.com>, Shahaf Shuler <shahafs@nvidia.com>, Matan Azrad <matan@nvidia.com> Message-ID: <20210315204856.615637a5@tanguero.localdomain> In-Reply-To: <DM6PR12MB3753ECA40CD54808E32EBF98DF6C9@DM6PR12MB3753.namprd12.prod.outlook.com> References: <1615822438-10082-1-git-send-email-iviktorin@fit.vutbr.cz> <1615822438-10082-2-git-send-email-iviktorin@fit.vutbr.cz> <DM6PR12MB3753C3CAF7C3840D296DEA19DF6C9@DM6PR12MB3753.namprd12.prod.outlook.com> <20210315171039.16b3965e@tanguero.localdomain> <DM6PR12MB3753ECA40CD54808E32EBF98DF6C9@DM6PR12MB3753.namprd12.prod.outlook.com> Organization: CESNET MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [dpdk-dev] [PATCH 2/2] net/mlx5: avoid unbind step to enable switchdev mode X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions <dev.dpdk.org> List-Unsubscribe: <https://mails.dpdk.org/options/dev>, <mailto:dev-request@dpdk.org?subject=unsubscribe> List-Archive: <http://mails.dpdk.org/archives/dev/> List-Post: <mailto:dev@dpdk.org> List-Help: <mailto:dev-request@dpdk.org?subject=help> List-Subscribe: <https://mails.dpdk.org/listinfo/dev>, <mailto:dev-request@dpdk.org?subject=subscribe> Errors-To: dev-bounces@dpdk.org Sender: "dev" <dev-bounces@dpdk.org> On Mon, 15 Mar 2021 19:31:25 +0000 Slava Ovsiienko <viacheslavo@nvidia.com> wrote: > Hi, Jan Hello Salva, I am sorry, but I didn't get the point of your response. For me, there was 1 PF 0000:05:00.1, SRIOV disabled. So, I followed the guide [1]. 1. Enable SRIOV via mlxconfig. Done. 2. Configure max number of VFs. Done. 3. Reset firmware. Done. In fact, I had to reboot the machine here so I am not convinced the reset of firmware is the thing. But I can image that there is some other use case for it. After reboot, I configured 2 VFs: 0000:05:00.4, 0000:05:00.5. 4. Unbind the PF 0000:05:00.1. Done. 5. Fail, no way how to configure switchdev because of previous step. Thus, I strongly believe that the guide is misleading here. When I bound the PF 0000:05:00.1 back, I could configure the switchdev mode and everything was just OK and seemed to be working. So **after** the bind I configured the switchdev mode properly. [1] https://doc.dpdk.org/guides/nics/mlx5.html#enable-switchdev-mode Jan > > 1. Let's suppose we have the one port NIC, PCI BDF 08:00.0, SR-IOV enabled, 0 VFs is configured, > netdev name is ens1f0 (depends on distro and kernel version). > > 2. Then, we configure 3 VFs with SR-IOV, we get : > - 08:00.0 - PF, ens1f0 > - 08:00.1 - VF0, ens1f1 > - 08:00.2 - VF1, ens1f2 > - 08:00.3 - VF2, ens1f3 > > 3. Then, we should unbind VFs ONLY, PF should be kept untouched. > - 08:00.0 - PF, ens1f0 > - 08:00.1 - VF0, - > - 08:00.2 - VF1, - > - 08:00.3 - VF2, - > > 4. Then, configure switchdev mode > - 08:00.0 - PF, ens1f0 > - 08:00.1 - VF0, - > - 08:00.2 - VF1, - > - 08:00.3 - VF2, - > + we get 3 representor netdevs: > ens1f0_0 (no dedicated PCI device) > ens1f0_1 (no dedicated PCI device) > ens1f0_2 (no dedicated PCI device) > > 5. Then, bind VFs back (assume we are no going to map them to VMs) > - 08:00.0 - PF, ens1f0 > - 08:00.1 - VF0, ens1f1 > - 08:00.2 - VF1, ens1f2 > - 08:00.3 - VF2, ens1f3 > - ens1f0_0 (no dedicated PCI device) > - ens1f0_1 (no dedicated PCI device) > - ens1f0_2 (no dedicated PCI device) > > 6. As result we should get 7 netdevs - 1 PF (Uplink representor), 3 VFs, 3 representors (no PCI device, pure netdev) > > With best regards, Slava > > > -----Original Message----- > > From: Jan Viktorin <viktorin@cesnet.cz> > > Sent: Monday, March 15, 2021 18:11 > > To: Slava Ovsiienko <viacheslavo@nvidia.com> > > Cc: dev@dpdk.org; Asaf Penso <asafp@nvidia.com>; Shahaf Shuler > > <shahafs@nvidia.com>; Matan Azrad <matan@nvidia.com> > > Subject: Re: [PATCH 2/2] net/mlx5: avoid unbind step to enable switchdev > > mode > > > > Hello Salva, > > > > On Mon, 15 Mar 2021 15:53:51 +0000 > > Slava Ovsiienko <viacheslavo@nvidia.com> wrote: > > > > > Hi, Jan > > > > > > Yes, bullet [4] explicitly requires to unbind VFs, and detach the netdevs > > from the mlx5_core driver. > > > Otherwise, kernel driver refuses to be configured with switchdev mode in > > [5]. So, [4] can't be skipped. > > > After setting swithdev mode, VFs can be bound back (if it is needed, and > > these ones are not mapped to VMs): > > > > OK, but I believe that it is **not possible** to follow the rule [5]. > > The guide explicitly says in [4] "can be rebind **after** the switchdev > > mode". > > Just, if you unbind the device, there is no way how to configure the > > switchdev mode, this is the contradiction I mentioned in the commit. You > > cannot configure switchdev mode because the interface is gone and the path > > /sys/class/net/<net device>/compat/devlink/mode no longer exists. > > > > So, maybe, just the formulation is wrong. So, what is the **exact > > right** way how to do it? I would change the commit accordingly. Just, let's > > make it right. Would it work this way? > > > > # echo -n "<device pci address>" > /sys/bus/pci/drivers/mlx5_core/unbind > > # echo -n "<device pci address>" > /sys/bus/pci/drivers/mlx5_core/bind > > # echo switchdev > /sys/class/net/<net device>/compat/devlink/mode > > > > It is good to mention that after the rebind, the <net device> can change. > > > > Regards, > > Jan > > > > > > > > echo -n "<device pci address>" > > /sys/bus/pci/drivers/mlx5_core/bind > > > > > > With best regards, > > > Slava > > > > > > > -----Original Message----- > > > > From: Jan Viktorin <iviktorin@fit.vutbr.cz> > > > > Sent: Monday, March 15, 2021 17:34 > > > > To: dev@dpdk.org > > > > Cc: Jan Viktorin <viktorin@cesnet.cz>; Asaf Penso > > > > <asafp@nvidia.com>; Shahaf Shuler <shahafs@nvidia.com>; Slava > > > > Ovsiienko <viacheslavo@nvidia.com>; Matan Azrad > > <matan@nvidia.com> > > > > Subject: [PATCH 2/2] net/mlx5: avoid unbind step to enable switchdev > > > > mode > > > > > > > > From: Jan Viktorin <viktorin@cesnet.cz> > > > > > > > > The step 4 is a contradiction. It advices to unbind the device from > > > > the mlx5_core which removes the associated system network interface > > (e.g. > > > > eth0). In the step 5, the same system network interface (e.g. eth0) > > > > is required to exist. > > > > > > > > Signed-off-by: Jan Viktorin <viktorin@cesnet.cz> > > > > --- > > > > doc/guides/nics/mlx5.rst | 6 +----- > > > > 1 file changed, 1 insertion(+), 5 deletions(-) > > > > > > > > diff --git a/doc/guides/nics/mlx5.rst b/doc/guides/nics/mlx5.rst > > > > index 0a2dc3dee..122d8e0fc 100644 > > > > --- a/doc/guides/nics/mlx5.rst > > > > +++ b/doc/guides/nics/mlx5.rst > > > > @@ -1370,11 +1370,7 @@ the DPDK application. > > > > > > > > echo <num of vfs > /sys/class/net/<net > > > > device>/device/sriov_numvfs > > > > > > > > -4. Unbind the device (can be rebind after the switchdev mode):: > > > > - > > > > - echo -n "<device pci address>" > > > > > /sys/bus/pci/drivers/mlx5_core/unbind > > > > - > > > > -5. Enable switchdev mode:: > > > > +4. Enable switchdev mode:: > > > > > > > > echo switchdev > /sys/class/net/<net > > > > device>/compat/devlink/mode > > > > > > > > -- > > > > 2.30.1 > > > >