On 12 May 2016 at 16:57, Santosh Shukla <santosh.shukla at caviumnetworks.com> wrote: > On Thu, May 12, 2016 at 01:54:13PM +0800, Jianbo Liu wrote: >> On 12 May 2016 at 13:06, Santosh Shukla >> <santosh.shukla at caviumnetworks.com> wrote: >> > On Thu, May 12, 2016 at 11:42:26AM +0800, Jianbo Liu wrote: >> >> On 12 May 2016 at 11:17, Santosh Shukla >> >> <santosh.shukla at caviumnetworks.com> wrote: >> >> > On Thu, May 12, 2016 at 10:01:05AM +0800, Jianbo Liu wrote: >> >> >> On 12 May 2016 at 02:25, Stephen Hemminger <stephen at >> >> >> networkplumber.org> wrote: >> >> >> > On Wed, 11 May 2016 22:32:16 +0530 >> >> >> > Jerin Jacob <jerin.jacob at caviumnetworks.com> wrote: >> >> >> > >> >> >> >> On Wed, May 11, 2016 at 08:22:59AM -0700, Stephen Hemminger wrote: >> >> >> >> > On Wed, 11 May 2016 19:17:58 +0530 >> >> >> >> > Hemant Agrawal <hemant.agrawal at nxp.com> wrote: >> >> >> >> > >> >> >> >> > > IGB_UIO not supported for arm64 arch in kernel so disable. >> >> >> >> > > >> >> >> >> > > Signed-off-by: Hemant Agrawal <hemant.agrawal at nxp.com> >> >> >> >> > > Reviewed-by: Santosh Shukla <santosh.shukla at >> >> >> >> > > caviumnetworks.com> >> >> >> >> > >> >> >> >> > Really, I have use IGB_UIO on ARM64 >> >> >> >> >> >> >> >> May I know what is the technical use case for igb_uio on arm64 >> >> >> >> which cannot be addressed through vfio or vfioionommu. >> >> >> > >> >> >> > I was running on older kernel which did not support vfioionommu mode. >> >> >> >> >> >> As I said, most of DPDK developers are not kernel developers. They may >> >> >> have their own kernel tree, and couldn't like to upgrade to latest >> >> >> kernel. >> >> >> They can choose to use or not use igb_uio when binding the driver. But >> >> >> blindly disabling it in the base config seems unreasonable. >> >> > >> >> > if user keeping his own kernel so they could also keep IGB_UIO=y in >> >> > their local >> >> Most likely they don't have local dpdk tree. They write their own >> >> applications, complie and link to dpdk lib, then done. >> >> >> >> > dpdk tree. Why are you imposing user-x custome depedancy on upstream >> >> > dpdk base >> >> Customer requiremnts is important. I want they can choose the way they >> >> like. >> >> >> > >> > so you choose to keep igb_uio option, provided arch doesn't support? >> > new user did reported issues with igb_uio for arm64, refer this thread >> > [1], as >> > well hemanth too faced issues. we want to avoid that. >> > >> > If customer maintaing out-of-tree kernel then he can also switch to >> > vfio-way. >> > isn;t it? >> > >> >> > config. Is it not enough for explanation that - Base config ie.. armv8 >> >> > doesn;t >> >> > support pci mmap, so igb_uio is n/a. New user wont able to build/run >> >> > dpdk/arm64 >> >> > in igb_uio-way, He'll prefer to use upstream stuff. I think, you are >> >> > not making >> >> You are wrong, he can build dpdk. If he like to use upstream without >> >> patching, he can use vfio. >> > >> > I disagree, we want to avoid [1] for new user. >> > >> >> But you can't ignore the need from old user which is more comfortable >> >> with older kernel. >> >> >> > arm/arm64 dpdk support recently added and I am guessing, most likely >> > customer >> > using near latest kernel, switching to vfio won't be so difficult. >> > >> > Or can you take up responsibility of upstreaming pci mmap patch, then we >> > don't >> > need this patch. >> > >> > [1] http://dpdk.org/ml/archives/dev/2016-January/031313.html >> >> Can you read carefully about the guide at >> http://dpdk.org/doc/guides/linux_gsg/build_dpdk.html? It says to use >> uio_pci_generic, igb_uio or vfio-pci. > > *** applicable and works for x86 only, not for arm64: because pci mmap support > not present for arm64, in that case we should update the doc. > >> Could it be possible that the user in that thread has already read and >> tried them all and found that he can't enable vifo with his kernel, >> and igb_uio is the easy way for him and asked for help from community? >> If so, we have no choice but keeping igb_uio enabled. > > By then vfionoiommu support was wip progress in dpdk/linux. but now it merged > and it works. So no need to retain igb_uio in base config for which to work - > user need to use mmap patch at linux side.
We can't decide which kernel user will use. > > Or can you maintain out-of-tree pci mmap patch/ kerne source and make it > explicit somewhere in dpdk build doc that - if user want igb_uio way then > use kernel/mmap patch from x location. The patch is in the kernel maillist, and user google it. And isn't funny to ask someone to do something again and again (3 times) in this thread? > >> He use lsmod to show us the modules, most likely he know vifo-pci. >> >> Below are the details on modules, hugepages and device binding. >> root at arm64:~# lsmod >> Module Size Used by >> rte_kni 292795 0 >> igb_uio 4338 0 >> ixgbe 184456 0
