3. Compiling and testing a PMD for a NIC

This section demonstrates how to compile and run a Poll Mode Driver (PMD) for the available Network Interface Cards in DPDK using TestPMD.

TestPMD is one of the reference applications distributed with the DPDK. Its main purpose is to forward packets between Ethernet ports on a network interface and as such is the best way to test a PMD.

Refer to the testpmd application user guide for detailed information on how to build and run testpmd.

3.1. Driver Compilation

To compile a PMD for a platform, run make with appropriate target as shown below. Use “make” command in Linux and “gmake” in FreeBSD. This will also build testpmd.

To check available targets:

cd <DPDK-source-directory>
make showconfigs

Example output:

arm-armv7a-linuxapp-gcc
arm64-armv8a-linuxapp-gcc
arm64-dpaa2-linuxapp-gcc
arm64-thunderx-linuxapp-gcc
arm64-xgene1-linuxapp-gcc
i686-native-linuxapp-gcc
i686-native-linuxapp-icc
ppc_64-power8-linuxapp-gcc
x86_64-native-bsdapp-clang
x86_64-native-bsdapp-gcc
x86_64-native-linuxapp-clang
x86_64-native-linuxapp-gcc
x86_64-native-linuxapp-icc
x86_x32-native-linuxapp-gcc

To compile a PMD for Linux x86_64 gcc target, run the following “make” command:

make install T=x86_64-native-linuxapp-gcc

Use ARM (ThunderX, DPAA, X-Gene) or PowerPC target for respective platform.

For more information, refer to the Getting Started Guide for Linux or Getting Started Guide for FreeBSD depending on your platform.

3.2. Running testpmd in Linux

This section demonstrates how to setup and run testpmd in Linux.

Mount huge pages:

mkdir /mnt/huge
mount -t hugetlbfs nodev /mnt/huge

Request huge pages:

Hugepage memory should be reserved as per application requirement. Check hugepage size configured in the system and calculate the number of pages required.

To reserve 1024 pages of 2MB:
```
echo 1024 > /sys/kernel/mm/hugepages/hugepages-2048kB/nr_hugepages
```
Note

Check /proc/meminfo to find system hugepage size:
```
grep "Hugepagesize:" /proc/meminfo
```
Example output:
```
Hugepagesize:       2048 kB
```

Load igb_uio or vfio-pci driver:

modprobe uio
insmod ./x86_64-native-linuxapp-gcc/kmod/igb_uio.ko

or

modprobe vfio-pci

Setup VFIO permissions for regular users before binding to vfio-pci:
```
sudo chmod a+x /dev/vfio

sudo chmod 0666 /dev/vfio/*
```
Bind the adapters to igb_uio or vfio-pci loaded in the previous step:
```
./usertools/dpdk-devbind.py --bind igb_uio DEVICE1 DEVICE2 ...
```
Or setup VFIO permissions for regular users and then bind to vfio-pci:
```
./usertools/dpdk-devbind.py --bind vfio-pci DEVICE1 DEVICE2 ...
```
Note

DEVICE1, DEVICE2 are specified via PCI “domain:bus:slot.func” syntax or “bus:slot.func” syntax.
Start testpmd with basic parameters:
```
./x86_64-native-linuxapp-gcc/app/testpmd -l 0-3 -n 4 -- -i
```
Successful execution will show initialization messages from EAL, PMD and testpmd application. A prompt will be displayed at the end for user commands as interactive mode (-i) is on.
```
testpmd>
```
Refer to the testpmd runtime functions for a list of available commands.

Note

When testpmd is built with shared library, use option -d to load the dynamic PMD for rte_eal_init.