How to install, build and use XDP related packages

PAGE UNDER CONSTRUCTION

There are multiple software packages that need to be downloaded, compiled, and installed for XPD-related code to run

Installing libbpf

1st: install the libelf library

sudo apt-get install -y libelf-dev

2nd: get and install the libbpf related files

export DESTDIR=<installation dir>
export PREFIX=""
git clone https://github.com/libbpf/libbpf.git
cd libbpf
cd src
make install
make install_uapi_headers

Get and install the libxpd related files

export DESTDIR=<installation dir>
export PREFIX=""
git clone https://github.com/xdp-project/xdp-tools.git
cd xdp-tools

Follow the instructions in xdp-tools/README.md file for compilation.

There is no need to do a git submodule on libbpf since we just installed it above.

Instructions are at https://github.com/xdp-project/xdp-tutorial , go to the setup_dependencies.org link at

https://github.com/xdp-project/xdp-tutorial/blob/master/setup_dependencies.org

This tells us to:

// (to get bpftool)
sudo apt install linux-tools-common linux-tools-generic
sudo apt install clang llvm libpcap-dev build-essential
sudo apt install linux-headers-$(uname -r)

// xdl-tools needs emacs
sudo apt install emacs

// you will need to use clang 11 for this to work so install and set commands to this version
sudo apt install clang-11 clang-format-11
sudo update-alternatives --install /usr/bin/clang clang /usr/bin/clang-11 100
sudo update-alternatives --install /usr/bin/clang++ clang++ /usr/bin/clang++-11 100
sudo update-alternatives --install /usr/bin/clang-format clang-format /usr/bin/clang-format-11 100
sudo update-alternatives --install /usr/bin/llc llc /usr/bin/llc-11 100

// check to see if this worked by doing
ls -al /usr/bin/clang*
ls -al /etc/alternatives/clang*
ls -al /usr/bin/llc*
ls -al /etc/alternatives/llc*

// now one can do
./configure
make

// to install
export DESTDIR=<install dir>
export LIBDIR=lib
export HDRDIR=include
export MANDIR=share
export SBINDIR=bin
export SCRIPTSDIR=scripts
make install

Get and install ejfat's XDP related files

git clone https://github.com/JeffersonLab/ejfat-xdp.git
cd ejfat-xdp
mkdir build
cd build
cmake ..
make install

Getting ready to use XDP sockets

• Each ejfat node has a Mellanox ConnectX-6 Dx NIC which can handle 2x100Gbps or 1x200Gbps.
• Avoid running XDP code in the skb (generic) mode in which the linux stack is NOT bypassed.
• Use the NIC's native mode I which the linux network stack is bypassed by placing code in the NIC driver of the kernel.