From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luca Boccassi Subject: Re: [PATCH v10 1/1] net/af_xdp: introduce AF XDP PMD driver Date: Thu, 04 Apr 2019 09:39:05 +0100 Message-ID: References: <20190301080947.91086-1-xiaolong.ye@intel.com> <20190403165949.44857-1-xiaolong.ye@intel.com> <20190403165949.44857-2-xiaolong.ye@intel.com> <25be95ff-132c-9e3e-fe3d-b5aac3dfb388@intel.com> <181fca1e5a2274ad2e7638c25b459ab7f426f254.camel@debian.org> <20190404055515.GB45121@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Cc: dev@dpdk.org, Stephen Hemminger , Qi Zhang , Karlsson Magnus , Topel Bjorn , Maxime Coquelin , Bruce Richardson , Ananyev Konstantin , David Marchand , Andrew Rybchenko , Olivier Matz To: Ye Xiaolong , Ferruh Yigit Return-path: Received: from mail-wr1-f68.google.com (mail-wr1-f68.google.com [209.85.221.68]) by dpdk.org (Postfix) with ESMTP id 48E573798 for ; Thu, 4 Apr 2019 10:39:09 +0200 (CEST) Received: by mail-wr1-f68.google.com with SMTP id s15so2554922wra.12 for ; Thu, 04 Apr 2019 01:39:09 -0700 (PDT) In-Reply-To: <20190404055515.GB45121@intel.com> 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 Thu, 2019-04-04 at 13:55 +0800, Ye Xiaolong wrote: > Hi, Luca >=20 > On 04/03, Luca Boccassi wrote: > > On Wed, 2019-04-03 at 18:44 +0100, Ferruh Yigit wrote: > > > On 4/3/2019 5:59 PM, Xiaolong Ye wrote: > > > > Add a new PMD driver for AF_XDP which is a proposed faster > > > > version > > > > of > > > > AF_PACKET interface in Linux. More info about AF_XDP, please > > > > refer > > > > to [1] > > > > [2]. > > > >=20 > > > > This is the vanilla version PMD which just uses a raw buffer > > > > registered as > > > > the umem. > > > >=20 > > > > [1]=20 > > > > https://fosdem.org/2018/schedule/event/af_xdp/ > > > >=20 > > > >=20 > > > > [2]=20 > > > > https://lwn.net/Articles/745934/ > > > >=20 > > > >=20 > > > >=20 > > > > Signed-off-by: Xiaolong Ye < > > > > xiaolong.ye@intel.com > > > >=20 > > >=20 > > > I am not able to test functionality but code looks good to me, I > > > can > > > compile via > > > Makefile (with suggested steps in doc) but not able to build with > > > meson, can you > > > please check below comments? > > >=20 > > > <...> > > >=20 > > > > @@ -0,0 +1,21 @@ > > > > +# SPDX-License-Identifier: BSD-3-Clause > > > > +# Copyright(c) 2019 Intel Corporation > > > > + > > > > +if host_machine.system() !=3D 'linux' > > > > + build =3D false > > > > +endif > > >=20 > > > After this point, if build is false it shouldn't continue to > > > below > > > checks I think. > > >=20 > > > > + > > > > +bpf_dep =3D dependency('libbpf', required: false) > > >=20 > > > My library is in '/usr/local/lib64/libbpf.so' but this line can't > > > find it. Where > > > does 'dependency()' checks for libraries? > >=20 > > dependency() uses only pkg-config (or cmake or embedded specific > > tools, > > neither of which applies to bpf), so if you haven't built from bpf- > > next=20 > > you won't have the pkg-config file installed, and it will fall back > > to > > the next block. > >=20 > > Side note, there's an issue open upstream in Meson to merge > > dependency() and find_library(), with some traction but it's not > > done > > yet. > >=20 > > For me building from bpf-next it works fine: > >=20 > > $ PKG_CONFIG_PATH=3D/tmp/bpf/lib64/pkgconfig/ ninja -C build-gcc- > > shared > > ... > > Dependency libbpf found: YES 0.0.2 > > ... > > $ lddtree build-gcc-shared/drivers/librte_pmd_af_xdp.so.1.1=20 > > librte_pmd_af_xdp.so.1.1 =3D> build-gcc- > > shared/drivers/librte_pmd_af_xdp.so.1.1 (interpreter =3D> none) > > libm.so.6 =3D> /lib/x86_64-linux-gnu/libm.so.6 > > libdl.so.2 =3D> /lib/x86_64-linux-gnu/libdl.so.2 > > libnuma.so.1 =3D> /lib/x86_64-linux-gnu/libnuma.so.1 > > librte_ethdev.so.12 =3D> build-gcc- > > shared/drivers/../lib/librte_ethdev.so.12 > > librte_eal.so.10 =3D> build-gcc- > > shared/drivers/../lib/librte_eal.so.10 > > librte_kvargs.so.1 =3D> build-gcc- > > shared/drivers/../lib/librte_kvargs.so.1 > > librte_net.so.1 =3D> build-gcc- > > shared/drivers/../lib/librte_net.so.1 > > librte_mbuf.so.5 =3D> build-gcc- > > shared/drivers/../lib/librte_mbuf.so.5 > > librte_mempool.so.5 =3D> build-gcc- > > shared/drivers/../lib/librte_mempool.so.5 > > librte_ring.so.2 =3D> build-gcc- > > shared/drivers/../lib/librte_ring.so.2 > > librte_cmdline.so.2 =3D> build-gcc- > > shared/drivers/../lib/librte_cmdline.so.2 > > librte_meter.so.2 =3D> build-gcc- > > shared/drivers/../lib/librte_meter.so.2 > > librte_bus_pci.so.2 =3D> not found > > librte_pci.so.1 =3D> build-gcc- > > shared/drivers/../lib/librte_pci.so.1 > > librte_bus_vdev.so.2 =3D> not found > > libbsd.so.0 =3D> /lib/x86_64-linux-gnu/libbsd.so.0 > > librt.so.1 =3D> /lib/x86_64-linux-gnu/librt.so.1 > > libbpf.so.0 =3D> /tmp/bpf/lib64/libbpf.so.0 > > libelf.so.1 =3D> /lib/x86_64-linux-gnu/libelf.so.1 > > libz.so.1 =3D> /lib/x86_64-linux-gnu/libz.so.1 > > libpthread.so.0 =3D> /lib/x86_64-linux-gnu/libpthread.so.0 > > libc.so.6 =3D> /lib/x86_64-linux-gnu/libc.so.6 > > ld-linux-x86-64.so.2 =3D> /lib/x86_64-linux-gnu/ld-linux-x86- > > 64.so.2 > >=20 > > > > +if bpf_dep.found() > > > > + build =3D true > > > > +else > > > > + bpf_dep =3D cc.find_library('libbpf', required: false) > > >=20 > > > Also this line can't find it, in log it says "(tried pkgconfig > > > and > > > cmake)" and > > > yes there is no pkgconfig for it, any idea how 'cmake' used? > >=20 > > The issue here is that it should be cc.find_library('bpf' - not > > 'libbpf'. I missed this when reviewing, good catch. > >=20 > > That's because find_library just does a compilation test passing > > the > > value to the compiler as a linker flag - so right now it's passing > > -llibbpf. Fixing this line and the header line below makes it work > > without pkg-config: > >=20 > > $ CPPFLAGS=3D-I/tmp/bpf/include LDFLAGS=3D-L/tmp/bpf/lib64 meson testt > > ... > > Dependency libbpf found: NO (tried pkgconfig and cmake) > > Library bpf found: YES >=20 > After apply the fix in af_xdp pmd's meson.build, now I was able to > build > library for af_xdp pmd. >=20 > $ ls drivers/ |grep xdp > a715181@@rte_pmd_af_xdp@sha > a715181@@rte_pmd_af_xdp@sta > a715181@@tmp_rte_pmd_af_xdp@sta > librte_pmd_af_xdp.a > librte_pmd_af_xdp.so > librte_pmd_af_xdp.so.1 > librte_pmd_af_xdp.so.1.1 > libtmp_rte_pmd_af_xdp.a > rte_pmd_af_xdp.pmd.c >=20 > But I found that if I install libbpf to /usr/local/lib64 by default, > application > built by meson build will fail to run: >=20 > $ ./dpdk-testpmd > ./dpdk-testpmd: error while loading shared libraries: libbpf.so.0: > cannot open shared object file: No such file or directory >=20 > While install libbpf to /usr/lib doesn't have this issue (I was > testing on ubuntu system). > Is it a expected behavior? Do we need any fix for it? Hi, That is expected and distro specific: if your distro doesn't add /usr/local/lib* to the compiler path, it also won't be in the LD_LIBRARY_PATH. So if you do: LD_LIBRARY_PATH=3D/usr/local/lib64 ./dpdk-testpmd It should then work. It's not related to the build system, but just to what the default paths are in the distro. --=20 Kind regards, Luca Boccassi