[dpdk-dev] [PATCH v9 1/1] net/af_xdp: introduce AF XDP PMD driver

[Luca Boccassi]

On Wed, 2019-04-03 at 12:35 +0100, Luca Boccassi wrote:
> On Wed, 2019-04-03 at 12:18 +0100, Ferruh Yigit wrote:
> > On 4/3/2019 11:42 AM, Luca Boccassi wrote:
> > > On Wed, 2019-04-03 at 11:36 +0100, Luca Boccassi wrote:
> > > > On Wed, 2019-04-03 at 17:59 +0800, Ye Xiaolong wrote:
> > > > > Hi, Luca
> > > > > 
> > > > > On 04/02, Luca Boccassi wrote:
> > > > > > On Tue, 2019-04-02 at 23:46 +0800, Xiaolong Ye wrote:
> > > > > > > diff --git a/drivers/net/af_xdp/Makefile
> > > > > > > b/drivers/net/af_xdp/Makefile
> > > > > > > new file mode 100644
> > > > > > > index 000000000..8343e3016
> > > > > > > --- /dev/null
> > > > > > > +++ b/drivers/net/af_xdp/Makefile
> > > > > > > @@ -0,0 +1,32 @@
> > > > > > > +# SPDX-License-Identifier: BSD-3-Clause
> > > > > > > +# Copyright(c) 2019 Intel Corporation
> > > > > > > +
> > > > > > > +include $(RTE_SDK)/mk/rte.vars.mk
> > > > > > > +
> > > > > > > +#
> > > > > > > +# library name
> > > > > > > +#
> > > > > > > +LIB = librte_pmd_af_xdp.a
> > > > > > > +
> > > > > > > +EXPORT_MAP := rte_pmd_af_xdp_version.map
> > > > > > > +
> > > > > > > +LIBABIVER := 1
> > > > > > > +
> > > > > > > +CFLAGS += -O3
> > > > > > > +
> > > > > > > +# require kernel version >= v5.1-rc1
> > > > > > > +CFLAGS += -I$(RTE_KERNELDIR)/tools/include
> > > > > > > +CFLAGS += -I$(RTE_KERNELDIR)/tools/lib/bpf
> > > > > > 
> > > > > > Sorry for not noticing this before, but doesn't this
> > > > > > require
> > > > > > the
> > > > > > full
> > > > > > kernel tree rather than just the typical headers package?
> > > > > > Requiring
> > > > > > the
> > > > > > full kernel tree to be available at build time will make
> > > > > > this
> > > > > > unbuildable on distros that still use makefiles, like RHEL
> > > > > > and
> > > > > > SUSE. At
> > > > > > least on Debian and Ubuntu, the kernel headers packages
> > > > > > distributed
> > > > > > do
> > > > > > not include the full kernel tree, only the headers, so
> > > > > > there's no
> > > > > > tools/lib or tools/include.
> > > > > 
> > > > > Currently we do have dependencies on the kernel src tree, as
> > > > > xsk.h
> > > > > and
> > > > > asm/barrier wouldn't be installed by libbpf, so before libbpf
> > > > > handles
> > > > > these
> > > > > properly, can we keep the current RTE_KERNELDIR in Makefile
> > > > > for
> > > > > now,
> > > > > and mention
> > > > > the dependencies in document, also suggest users to config
> > > > > RTE_KERNELDIR to correct
> > > > > kernel src tree if they want to use af_xdp pmd?
> > > > > 
> > > > > Something like:
> > > > > 
> > > > > dependencies:
> > > > > - kernel source code (>= v5.1-rc1)
> > > > > - build libbfp and install
> > > > > 
> > > > > Thanks,
> > > > > Xiaolong
> > > > 
> > > > asm/barrier.h is installed by the kernel headers packages so it
> > > > would
> > > > be fine (although not ideal) and not need the full source tree.
> > > > xsk.h is a bit more worrying, as it looks like an internal
> > > > header
> > > > from
> > > > here.
> > > > 
> > > > Is it really necessary for external applications to use an
> > > > internal-
> > > > only header and a kernel header to be able to use libbpf?
> > > 
> > > Actually, xsk.h is now installed by the library makefile:
> > > 
> > > https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=379e2014c95b
> > > 
> > > 
> > 
> > Good to have this one. But again it is in BPF tree and it won't be
> > in
> > 5.1.
> 
> It looks like a small and required bug fix to me, and 5.1 is still in
> RC state, so perhaps there's still time.
> 
> Bjorn and Magnus, any chance the above makefile install fix could be
> sent for inclusion in 5.1-rc4?

Actually the bpf tree was already merged in the net tree a couple of
days ago. As far as I understand from the process, this should mean
that this fix should be set for inclusion in Linus' tree in time for
5.1-rc4:

https://git.kernel.org/pub/scm/linux/kernel/git/davem/net.git/commit?id=379e2014c95b7a454713da822b8ef4ec51ab8a75

-- 
Kind regards,
Luca Boccassi