From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bruce Richardson Subject: Re: [PATCH v3] drivers: advertise kmod dependencies in pmdinfo Date: Fri, 16 Dec 2016 13:04:56 +0000 Message-ID: <20161216130456.GA154860@bricha3-MOBL3.ger.corp.intel.com> References: <1479808257-8725-1-git-send-email-olivier.matz@6wind.com> <1481809599-27896-1-git-send-email-olivier.matz@6wind.com> <20161215160912.GA4450@neilslaptop.think-freely.org> <20161215092207.168ba141@xeon-e3> <20161216102208.08955321@platinum> <20161216123738.GA2255@hmsreliant.think-freely.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Olivier Matz , Stephen Hemminger , dev@dpdk.org, thomas.monjalon@6wind.com, vido@cesnet.cz, fiona.trahe@intel.com, adrien.mazarguil@6wind.com To: Neil Horman Return-path: Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by dpdk.org (Postfix) with ESMTP id 72E29379E for ; Fri, 16 Dec 2016 14:05:01 +0100 (CET) Content-Disposition: inline In-Reply-To: <20161216123738.GA2255@hmsreliant.think-freely.org> List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On Fri, Dec 16, 2016 at 07:37:38AM -0500, Neil Horman wrote: > On Fri, Dec 16, 2016 at 10:22:08AM +0100, Olivier Matz wrote: > > Hi, > > > > On Thu, 15 Dec 2016 09:22:07 -0800, Stephen Hemminger > > wrote: > > > On Thu, 15 Dec 2016 11:09:12 -0500 > > > Neil Horman wrote: > > > > > > > On Thu, Dec 15, 2016 at 02:46:39PM +0100, Olivier Matz wrote: > > > > > Add a new macro RTE_PMD_REGISTER_KMOD_DEP() that allows a driver > > > > > to declare the list of kernel modules required to run properly. > > > > > > > > > > Today, most PCI drivers require uio/vfio. > > > > > > > > > > Signed-off-by: Olivier Matz > > > > > Acked-by: Fiona Trahe > > > > > --- > > > > > > > > > > v2 -> v3: > > > > > - fix kmods deps advertised by mellanox drivers as pointed out > > > > > by Adrien > > > > > > > > > > v1 -> > > > > > v2: > > > > > - do not advertise uio_pci_generic for vf drivers > > > > > - rebase on top of head: use new driver names and prefix > > > > > macro with > > > > > RTE_ > > > > > > > > > > rfc -> v1: > > > > > - the kmod information can be per-device using a modalias-like > > > > > pattern > > > > > - change syntax to use '&' and '|' instead of ',' and ':' > > > > > - remove useless prerequisites in kmod lis: no need to > > > > > specify both uio and uio_pci_generic, only the latter is > > > > > required > > > > > - update kmod list in szedata2 driver > > > > > - remove kmod list in qat driver: it requires more than just > > > > > loading a kmod, which is described in documentation > > > > > > > > > > buildtools/pmdinfogen/pmdinfogen.c | 1 + > > > > > buildtools/pmdinfogen/pmdinfogen.h | 1 + > > > > > drivers/net/bnx2x/bnx2x_ethdev.c | 2 ++ > > > > > drivers/net/bnxt/bnxt_ethdev.c | 1 + > > > > > drivers/net/cxgbe/cxgbe_ethdev.c | 1 + > > > > > drivers/net/e1000/em_ethdev.c | 1 + > > > > > drivers/net/e1000/igb_ethdev.c | 2 ++ > > > > > drivers/net/ena/ena_ethdev.c | 1 + > > > > > drivers/net/enic/enic_ethdev.c | 1 + > > > > > drivers/net/fm10k/fm10k_ethdev.c | 1 + > > > > > drivers/net/i40e/i40e_ethdev.c | 1 + > > > > > drivers/net/i40e/i40e_ethdev_vf.c | 1 + > > > > > drivers/net/ixgbe/ixgbe_ethdev.c | 2 ++ > > > > > drivers/net/mlx4/mlx4.c | 2 ++ > > > > > drivers/net/mlx5/mlx5.c | 1 + > > > > > drivers/net/nfp/nfp_net.c | 1 + > > > > > drivers/net/qede/qede_ethdev.c | 2 ++ > > > > > drivers/net/szedata2/rte_eth_szedata2.c | 2 ++ > > > > > drivers/net/thunderx/nicvf_ethdev.c | 1 + > > > > > drivers/net/virtio/virtio_ethdev.c | 1 + > > > > > drivers/net/vmxnet3/vmxnet3_ethdev.c | 1 + > > > > > lib/librte_eal/common/include/rte_dev.h | 25 > > > > > +++++++++++++++++++++++++ tools/dpdk-pmdinfo.py > > > > > | 5 ++++- 23 files changed, 56 insertions(+), 1 deletion(-) > > > > > > > > > Its odd that all devices, regardless of vendor should depend on the > > > > igb_uio module. It seems to me that depending on uio_pci_generic > > > > or vfio is sufficient. > > > > igb_uio is the historical uio module of dpdk. Although it is called > > igb_uio, it is not specific to Intel drivers. > > > > Most drivers declare "igb_uio | uio_pci_generic | vfio", which means > > that any of the 3 kernel modules can be used. > > > > I think there are some cases where people will prefer using igb_uio, > > for instance to use a vf pmd in a vm where there is no iommu, > > and where the kernel vfio module does not support the no-iommu mode. > > > > > > > > > > Yes it seems just a special case extension for Mellanox drivers. > > > > Kmod deps are different whether it's a vf driver or not. > > Mellanox drivers are not the only drivers that do not require uio, > > there is also szedata2. > > > > Is it an argument for not including this patch? > > > Speaking only for myself, I'm not suggesting the patch not be included, only > questioning the need to list igb_uio as an optional dependency. From what I > understand uio_pci_generic is equaly capable of being used in a vf as igb_uio, > and so it seems like its sufficient to list in the deps alone, or am I missing > something? > Unfortunately uio_pci_generic cannot be used with VFs either inside or outside a VM, as VFs use MSI/MSI-X rather than legacy interrupts. For newer kernels with vfio-noiommu, that is an option, but for any other case, igb_uio is needed. /Bruce