Refactor the INSTALL.DPDK in to two documents named INSTALL.DPDK and INSTALL.DPDK-ADVANCED. While INSTALL.DPDK document shall facilitate the novice user in setting up the OVS DPDK and running it out of box, the ADVANCED document is targeted at expert users looking for the optimum performance running dpdk datapath.
This commit updates INSTALL.DPDK.md document. Signed-off-by: Bhanuprakash Bodireddy <bhanuprakash.bodire...@intel.com> --- INSTALL.DPDK.md | 1303 ++++++++++++++++++------------------------------------- 1 file changed, 430 insertions(+), 873 deletions(-) diff --git a/INSTALL.DPDK.md b/INSTALL.DPDK.md index c2e32bf..283504b 100644 --- a/INSTALL.DPDK.md +++ b/INSTALL.DPDK.md @@ -1,1024 +1,581 @@ -Using Open vSwitch with DPDK -============================ +OVS DPDK INSTALL GUIDE +================================ -Open vSwitch can use Intel(R) DPDK lib to operate entirely in -userspace. This file explains how to install and use Open vSwitch in -such a mode. +## Contents -The DPDK support of Open vSwitch is considered experimental. -It has not been thoroughly tested. +1. [Overview](#overview) +2. [Building and Installation](#build) +3. [Setup OVS DPDK datapath](#ovssetup) +4. [DPDK in the VM](#builddpdk) +5. [OVS Testcases](#ovstc) +6. [Limitations ](#ovslimits) -This version of Open vSwitch should be built manually with `configure` -and `make`. +## <a name="overview"></a> 1. Overview -OVS needs a system with 1GB hugepages support. +Open vSwitch can use DPDK lib to operate entirely in userspace. +This file provides information on installation and use of Open vSwitch +using DPDK datapath. This version of Open vSwitch should be built manually +with `configure` and `make`. -Building and Installing: ------------------------- +The DPDK support of Open vSwitch is considered 'experimental'. -Required: DPDK 16.04 -Optional (if building with vhost-cuse): `fuse`, `fuse-devel` (`libfuse-dev` -on Debian/Ubuntu) +### Prerequisites -1. Configure build & install DPDK: - 1. Set `$DPDK_DIR` +* Required: DPDK 16.04 +* Hardware: [DPDK Supported NICs] when physical ports in use - ``` - export DPDK_DIR=/usr/src/dpdk-16.04 - cd $DPDK_DIR - ``` - - 2. Then run `make install` to build and install the library. - For default install without IVSHMEM: - - `make install T=x86_64-native-linuxapp-gcc DESTDIR=install` - - To include IVSHMEM (shared memory): - - `make install T=x86_64-ivshmem-linuxapp-gcc DESTDIR=install` - - For further details refer to http://dpdk.org/ - -2. Configure & build the Linux kernel: - - Refer to intel-dpdk-getting-started-guide.pdf for understanding - DPDK kernel requirement. - -3. Configure & build OVS: - - * Non IVSHMEM: - - `export DPDK_BUILD=$DPDK_DIR/x86_64-native-linuxapp-gcc/` - - * IVSHMEM: - - `export DPDK_BUILD=$DPDK_DIR/x86_64-ivshmem-linuxapp-gcc/` - - ``` - cd $(OVS_DIR)/ - ./boot.sh - ./configure --with-dpdk=$DPDK_BUILD [CFLAGS="-g -O2 -Wno-cast-align"] - make - ``` - - Note: 'clang' users may specify the '-Wno-cast-align' flag to suppress DPDK cast-align warnings. - -To have better performance one can enable aggressive compiler optimizations and -use the special instructions(popcnt, crc32) that may not be available on all -machines. Instead of typing `make`, type: - -`make CFLAGS='-O3 -march=native'` - -Refer to [INSTALL.userspace.md] for general requirements of building userspace OVS. - -Using the DPDK with ovs-vswitchd: ---------------------------------- - -1. Setup system boot - Add the following options to the kernel bootline: - - `default_hugepagesz=1GB hugepagesz=1G hugepages=1` - -2. Setup DPDK devices: - - DPDK devices can be setup using either the VFIO (for DPDK 1.7+) or UIO - modules. UIO requires inserting an out of tree driver igb_uio.ko that is - available in DPDK. Setup for both methods are described below. - - * UIO: - 1. insert uio.ko: `modprobe uio` - 2. insert igb_uio.ko: `insmod $DPDK_BUILD/kmod/igb_uio.ko` - 3. Bind network device to igb_uio: - `$DPDK_DIR/tools/dpdk_nic_bind.py --bind=igb_uio eth1` - - * VFIO: - - VFIO needs to be supported in the kernel and the BIOS. More information - can be found in the [DPDK Linux GSG]. - - 1. Insert vfio-pci.ko: `modprobe vfio-pci` - 2. Set correct permissions on vfio device: `sudo /usr/bin/chmod a+x /dev/vfio` - and: `sudo /usr/bin/chmod 0666 /dev/vfio/*` - 3. Bind network device to vfio-pci: - `$DPDK_DIR/tools/dpdk_nic_bind.py --bind=vfio-pci eth1` - -3. Mount the hugetable filesystem - - `mount -t hugetlbfs -o pagesize=1G none /dev/hugepages` - - Ref to http://www.dpdk.org/doc/quick-start for verifying DPDK setup. - -4. Follow the instructions in [INSTALL.md] to install only the - userspace daemons and utilities (via 'make install'). - 1. First time only db creation (or clearing): - - ``` - mkdir -p /usr/local/etc/openvswitch - mkdir -p /usr/local/var/run/openvswitch - rm /usr/local/etc/openvswitch/conf.db - ovsdb-tool create /usr/local/etc/openvswitch/conf.db \ - /usr/local/share/openvswitch/vswitch.ovsschema - ``` - - 2. Start ovsdb-server - - ``` - ovsdb-server --remote=punix:/usr/local/var/run/openvswitch/db.sock \ - --remote=db:Open_vSwitch,Open_vSwitch,manager_options \ - --private-key=db:Open_vSwitch,SSL,private_key \ - --certificate=Open_vSwitch,SSL,certificate \ - --bootstrap-ca-cert=db:Open_vSwitch,SSL,ca_cert --pidfile --detach - ``` - - 3. First time after db creation, initialize: - - ``` - ovs-vsctl --no-wait init - ``` - -5. Start vswitchd: - - DPDK configuration arguments can be passed to vswitchd via Open_vSwitch - other_config column. The recognized configuration options are listed. - Defaults will be provided for all values not explicitly set. - - * dpdk-init - Specifies whether OVS should initialize and support DPDK ports. This is - a boolean, and defaults to false. - - * dpdk-lcore-mask - Specifies the CPU cores on which dpdk lcore threads should be spawned. - The DPDK lcore threads are used for DPDK library tasks, such as - library internal message processing, logging, etc. Value should be in - the form of a hex string (so '0x123') similar to the 'taskset' mask - input. - If not specified, the value will be determined by choosing the lowest - CPU core from initial cpu affinity list. Otherwise, the value will be - passed directly to the DPDK library. - For performance reasons, it is best to set this to a single core on - the system, rather than allow lcore threads to float. - - * dpdk-alloc-mem - This sets the total memory to preallocate from hugepages regardless of - processor socket. It is recommended to use dpdk-socket-mem instead. - - * dpdk-socket-mem - Comma separated list of memory to pre-allocate from hugepages on specific - sockets. - - * dpdk-hugepage-dir - Directory where hugetlbfs is mounted - - * dpdk-extra - Extra arguments to provide to DPDK EAL, as previously specified on the - command line. Do not pass '--no-huge' to the system in this way. Support - for running the system without hugepages is nonexistent. - - * cuse-dev-name - Option to set the vhost_cuse character device name. - - * vhost-sock-dir - Option to set the path to the vhost_user unix socket files. - - NOTE: Changing any of these options requires restarting the ovs-vswitchd - application. - - Open vSwitch can be started as normal. DPDK will be initialized as long - as the dpdk-init option has been set to 'true'. - - - ``` - export DB_SOCK=/usr/local/var/run/openvswitch/db.sock - ovs-vsctl --no-wait set Open_vSwitch . other_config:dpdk-init=true - ovs-vswitchd unix:$DB_SOCK --pidfile --detach - ``` - - If allocated more than one GB hugepage (as for IVSHMEM), set amount and - use NUMA node 0 memory: - - ``` - ovs-vsctl --no-wait set Open_vSwitch . other_config:dpdk-socket-mem="1024,0" - ovs-vswitchd unix:$DB_SOCK --pidfile --detach - ``` - -6. Add bridge & ports - - To use ovs-vswitchd with DPDK, create a bridge with datapath_type - "netdev" in the configuration database. For example: - - `ovs-vsctl add-br br0 -- set bridge br0 datapath_type=netdev` - - Now you can add dpdk devices. OVS expects DPDK device names to start with - "dpdk" and end with a portid. vswitchd should print (in the log file) the - number of dpdk devices found. - - ``` - ovs-vsctl add-port br0 dpdk0 -- set Interface dpdk0 type=dpdk - ovs-vsctl add-port br0 dpdk1 -- set Interface dpdk1 type=dpdk - ``` - - Once first DPDK port is added to vswitchd, it creates a Polling thread and - polls dpdk device in continuous loop. Therefore CPU utilization - for that thread is always 100%. - - Note: creating bonds of DPDK interfaces is slightly different to creating - bonds of system interfaces. For DPDK, the interface type must be explicitly - set, for example: - - ``` - ovs-vsctl add-bond br0 dpdkbond dpdk0 dpdk1 -- set Interface dpdk0 type=dpdk -- set Interface dpdk1 type=dpdk - ``` - -7. Add test flows - - Test flow script across NICs (assuming ovs in /usr/src/ovs): - Execute script: - - ``` - #! /bin/sh - # Move to command directory - cd /usr/src/ovs/utilities/ - - # Clear current flows - ./ovs-ofctl del-flows br0 - - # Add flows between port 1 (dpdk0) to port 2 (dpdk1) - ./ovs-ofctl add-flow br0 in_port=1,action=output:2 - ./ovs-ofctl add-flow br0 in_port=2,action=output:1 - ``` - -8. QoS usage example - - Assuming you have a vhost-user port transmitting traffic consisting of - packets of size 64 bytes, the following command would limit the egress - transmission rate of the port to ~1,000,000 packets per second: - - `ovs-vsctl set port vhost-user0 qos=@newqos -- --id=@newqos create qos - type=egress-policer other-config:cir=46000000 other-config:cbs=2048` - - To examine the QoS configuration of the port: - - `ovs-appctl -t ovs-vswitchd qos/show vhost-user0` - - To clear the QoS configuration from the port and ovsdb use the following: - - `ovs-vsctl destroy QoS vhost-user0 -- clear Port vhost-user0 qos` - - For more details regarding egress-policer parameters please refer to the - vswitch.xml. - -9. Ingress Policing Example - - Assuming you have a vhost-user port receiving traffic consisting of - packets of size 64 bytes, the following command would limit the reception - rate of the port to ~1,000,000 packets per second: - - `ovs-vsctl set interface vhost-user0 ingress_policing_rate=368000 - ingress_policing_burst=1000` - - To examine the ingress policer configuration of the port: - - `ovs-vsctl list interface vhost-user0` - - To clear the ingress policer configuration from the port use the following: - - `ovs-vsctl set interface vhost-user0 ingress_policing_rate=0` - - For more details regarding ingress-policer see the vswitch.xml. - -Performance Tuning: -------------------- - -1. PMD affinitization - - A poll mode driver (pmd) thread handles the I/O of all DPDK - interfaces assigned to it. A pmd thread will busy loop through - the assigned port/rxq's polling for packets, switch the packets - and send to a tx port if required. Typically, it is found that - a pmd thread is CPU bound, meaning that the greater the CPU - occupancy the pmd thread can get, the better the performance. To - that end, it is good practice to ensure that a pmd thread has as - many cycles on a core available to it as possible. This can be - achieved by affinitizing the pmd thread with a core that has no - other workload. See section 7 below for a description of how to - isolate cores for this purpose also. - - The following command can be used to specify the affinity of the - pmd thread(s). - - `ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=<hex string>` +## <a name="build"></a> 2. Building and Installation - By setting a bit in the mask, a pmd thread is created and pinned - to the corresponding CPU core. e.g. to run a pmd thread on core 1 +### 2.1 Configure & build the Linux kernel - `ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=2` +On Linux Distros running kernel version >= 3.0, kernel rebuild is not required +and only grub cmdline needs to be updated for enabling IOMMU [VFIO support - 3.2]. +For older kernels, check if kernel is built with UIO, HUGETLBFS, PROC_PAGE_MONITOR, +HPET, HPET_MMAP support. - For more information, please refer to the Open_vSwitch TABLE section in +Detailed system requirements can be found at [DPDK requirements] and also refer to +advanced install guide [INSTALL.DPDK-ADVANCED.md] - `man ovs-vswitchd.conf.db` +### 2.2 Install DPDK + 1. [Download DPDK] and extract the file, for example in to /usr/src + and set DPDK_DIR - Note, that a pmd thread on a NUMA node is only created if there is - at least one DPDK interface from that NUMA node added to OVS. - -2. Multiple poll mode driver threads - - With pmd multi-threading support, OVS creates one pmd thread - for each NUMA node by default. However, it can be seen that in cases - where there are multiple ports/rxq's producing traffic, performance - can be improved by creating multiple pmd threads running on separate - cores. These pmd threads can then share the workload by each being - responsible for different ports/rxq's. Assignment of ports/rxq's to - pmd threads is done automatically. - - The following command can be used to specify the affinity of the - pmd threads. - - `ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=<hex string>` - - A set bit in the mask means a pmd thread is created and pinned - to the corresponding CPU core. e.g. to run pmd threads on core 1 and 2 - - `ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=6` - - For more information, please refer to the Open_vSwitch TABLE section in - - `man ovs-vswitchd.conf.db` - - For example, when using dpdk and dpdkvhostuser ports in a bi-directional - VM loopback as shown below, spreading the workload over 2 or 4 pmd - threads shows significant improvements as there will be more total CPU - occupancy available. - - NIC port0 <-> OVS <-> VM <-> OVS <-> NIC port 1 - - The following command can be used to confirm that the port/rxq assignment - to pmd threads is as required: - - `ovs-appctl dpif-netdev/pmd-rxq-show` - - This can also be checked with: - - ``` - top -H - taskset -p <pid_of_pmd> - ``` - - To understand where most of the pmd thread time is spent and whether the - caches are being utilized, these commands can be used: - - ``` - # Clear previous stats - ovs-appctl dpif-netdev/pmd-stats-clear - - # Check current stats - ovs-appctl dpif-netdev/pmd-stats-show - ``` - -3. DPDK port Rx Queues - - `ovs-vsctl set Interface <DPDK interface> options:n_rxq=<integer>` - - The command above sets the number of rx queues for DPDK interface. - The rx queues are assigned to pmd threads on the same NUMA node in a - round-robin fashion. For more information, please refer to the - Open_vSwitch TABLE section in - - `man ovs-vswitchd.conf.db` - -4. Exact Match Cache - - Each pmd thread contains one EMC. After initial flow setup in the - datapath, the EMC contains a single table and provides the lowest level - (fastest) switching for DPDK ports. If there is a miss in the EMC then - the next level where switching will occur is the datapath classifier. - Missing in the EMC and looking up in the datapath classifier incurs a - significant performance penalty. If lookup misses occur in the EMC - because it is too small to handle the number of flows, its size can - be increased. The EMC size can be modified by editing the define - EM_FLOW_HASH_SHIFT in lib/dpif-netdev.c. - - As mentioned above an EMC is per pmd thread. So an alternative way of - increasing the aggregate amount of possible flow entries in EMC and - avoiding datapath classifier lookups is to have multiple pmd threads - running. This can be done as described in section 2. - -5. Compiler options - - The default compiler optimization level is '-O2'. Changing this to - more aggressive compiler optimizations such as '-O3' or - '-Ofast -march=native' with gcc can produce performance gains. - -6. Simultaneous Multithreading (SMT) - - With SMT enabled, one physical core appears as two logical cores - which can improve performance. - - SMT can be utilized to add additional pmd threads without consuming - additional physical cores. Additional pmd threads may be added in the - same manner as described in section 2. If trying to minimize the use - of physical cores for pmd threads, care must be taken to set the - correct bits in the pmd-cpu-mask to ensure that the pmd threads are - pinned to SMT siblings. - - For example, when using 2x 10 core processors in a dual socket system - with HT enabled, /proc/cpuinfo will report 40 logical cores. To use - two logical cores which share the same physical core for pmd threads, - the following command can be used to identify a pair of logical cores. - - `cat /sys/devices/system/cpu/cpuN/topology/thread_siblings_list` - - where N is the logical core number. In this example, it would show that - cores 1 and 21 share the same physical core. The pmd-cpu-mask to enable - two pmd threads running on these two logical cores (one physical core) - is. + ``` + cd /usr/src/ + wget http://dpdk.org/browse/dpdk/snapshot/dpdk-16.04.zip + unzip dpdk-16.04.zip - `ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=100002` + export DPDK_DIR=/usr/src/dpdk-16.04 + cd $DPDK_DIR + ``` - Note that SMT is enabled by the Hyper-Threading section in the - BIOS, and as such will apply to the whole system. So the impact of - enabling/disabling it for the whole system should be considered - e.g. If workloads on the system can scale across multiple cores, - SMT may very beneficial. However, if they do not and perform best - on a single physical core, SMT may not be beneficial. + 2. Configure and Install DPDK -7. The isolcpus kernel boot parameter + Build and install the DPDK library. - isolcpus can be used on the kernel bootline to isolate cores from the - kernel scheduler and hence dedicate them to OVS or other packet - forwarding related workloads. For example a Linux kernel boot-line - could be: + ``` + export DPDK_TARGET=x86_64-native-linuxapp-gcc + export DPDK_BUILD=$DPDK_DIR/$DPDK_TARGET + make install T=$DPDK_TARGET DESTDIR=install + ``` - ``` - GRUB_CMDLINE_LINUX_DEFAULT="quiet hugepagesz=1G hugepages=4 - default_hugepagesz=1G 'intel_iommu=off' isolcpus=1-19" - ``` + Note: For IVSHMEM, Set `export DPDK_TARGET=x86_64-ivshmem-linuxapp-gcc` -8. NUMA/Cluster On Die +### 2.3 Install OVS + OVS can be installed using different methods. For OVS to use DPDK datapath, + it has to be configured with DPDK support and is done by './configure --with-dpdk'. + This section focus on generic recipe that suits most cases and for distribution + specific instructions, refer [INSTALL.Fedora.md], [INSTALL.RHEL.md] and + [INSTALL.Debian.md]. - Ideally inter NUMA datapaths should be avoided where possible as packets - will go across QPI and there may be a slight performance penalty when - compared with intra NUMA datapaths. On Intel Xeon Processor E5 v3, - Cluster On Die is introduced on models that have 10 cores or more. - This makes it possible to logically split a socket into two NUMA regions - and again it is preferred where possible to keep critical datapaths - within the one cluster. + The OVS sources can be downloaded in different ways and skip this section + if already having the correct sources. Otherwise download the correct version using + one of the below suggested methods and follow the documentation of that specific + version. - It is good practice to ensure that threads that are in the datapath are - pinned to cores in the same NUMA area. e.g. pmd threads and QEMU vCPUs - responsible for forwarding. + - OVS stable releases can be downloaded in compressed format from [Download OVS] -9. Rx Mergeable buffers + ``` + cd /usr/src + wget http://openvswitch.org/releases/openvswitch-<version>.tar.gz + tar -zxvf openvswitch-<version>.tar.gz + export OVS_DIR=/usr/src/openvswitch-<version> + ``` - Rx Mergeable buffers is a virtio feature that allows chaining of multiple - virtio descriptors to handle large packet sizes. As such, large packets - are handled by reserving and chaining multiple free descriptors - together. Mergeable buffer support is negotiated between the virtio - driver and virtio device and is supported by the DPDK vhost library. - This behavior is typically supported and enabled by default, however - in the case where the user knows that rx mergeable buffers are not needed - i.e. jumbo frames are not needed, it can be forced off by adding - mrg_rxbuf=off to the QEMU command line options. By not reserving multiple - chains of descriptors it will make more individual virtio descriptors - available for rx to the guest using dpdkvhost ports and this can improve - performance. + - OVS current development can be downloaded in compressed format from + https://github.com/openvswitch/ovs/tarball/master -10. Packet processing in the guest + ``` + wget -O ovs.tar https://github.com/openvswitch/ovs/tarball/master + mkdir -p /usr/src/ovs + tar -xvf ovs.tar -C /usr/src/ovs --strip-components=1 + export OVS_DIR=/usr/src/ovs + ``` - It is good practice whether simply forwarding packets from one - interface to another or more complex packet processing in the guest, - to ensure that the thread performing this work has as much CPU - occupancy as possible. For example when the DPDK sample application - `testpmd` is used to forward packets in the guest, multiple QEMU vCPU - threads can be created. Taskset can then be used to affinitize the - vCPU thread responsible for forwarding to a dedicated core not used - for other general processing on the host system. + - OVS current development can be clone using 'git' tool -11. DPDK virtio pmd in the guest + ``` + cd /usr/src/ + git clone https://github.com/openvswitch/ovs.git + export OVS_DIR=/usr/src/ovs + ``` - dpdkvhostcuse or dpdkvhostuser ports can be used to accelerate the path - to the guest using the DPDK vhost library. This library is compatible with - virtio-net drivers in the guest but significantly better performance can - be observed when using the DPDK virtio pmd driver in the guest. The DPDK - `testpmd` application can be used in the guest as an example application - that forwards packet from one DPDK vhost port to another. An example of - running `testpmd` in the guest can be seen here. + - Install OVS dependencies - ``` - ./testpmd -c 0x3 -n 4 --socket-mem 512 -- --burst=64 -i --txqflags=0xf00 - --disable-hw-vlan --forward-mode=io --auto-start - ``` + GNU make, GCC 4.x (or) Clang 3.4 (Mandatory) + libssl, libcap-ng, Python 2.7 (Optional) + More information can be found at [Build Requirements] - See below information on dpdkvhostcuse and dpdkvhostuser ports. - See [DPDK Docs] for more information on `testpmd`. + - Configure, Install OVS -DPDK Rings : ------------- + ``` + cd $OVS_DIR + ./boot.sh + ./configure --with-dpdk=$DPDK_BUILD + make install + ``` -Following the steps above to create a bridge, you can now add dpdk rings -as a port to the vswitch. OVS will expect the DPDK ring device name to -start with dpdkr and end with a portid. + Note: Passing DPDK_BUILD can be skipped if DPDK library is installed in + standard locations i.e `./configure --with-dpdk` should suffice. -`ovs-vsctl add-port br0 dpdkr0 -- set Interface dpdkr0 type=dpdkr` + Additional information can be found in [INSTALL.md]. -DPDK rings client test application +## <a name="ovssetup"></a> 3. Setup OVS with DPDK datapath -Included in the test directory is a sample DPDK application for testing -the rings. This is from the base dpdk directory and modified to work -with the ring naming used within ovs. +### 3.1 Setup Hugepages -location tests/ovs_client + Allocate and mount 2M Huge pages: -To run the client : + - For persistent allocation of huge pages, write to hugepages.conf file + in /etc/sysctl.d -``` -cd /usr/src/ovs/tests/ -ovsclient -c 1 -n 4 --proc-type=secondary -- -n "port id you gave dpdkr" -``` + `echo 'vm.nr_hugepages=2048' > /etc/sysctl.d/hugepages.conf` -In the case of the dpdkr example above the "port id you gave dpdkr" is 0. + - For run-time allocation of huge pages -It is essential to have --proc-type=secondary + `sysctl -w vm.nr_hugepages=N` where N = No. of 2M huge pages allocated -The application simply receives an mbuf on the receive queue of the -ethernet ring and then places that same mbuf on the transmit ring of -the ethernet ring. It is a trivial loopback application. + - To verify hugepage configuration -DPDK rings in VM (IVSHMEM shared memory communications) -------------------------------------------------------- + `grep HugePages_ /proc/meminfo` -In addition to executing the client in the host, you can execute it within -a guest VM. To do so you will need a patched qemu. You can download the -patch and getting started guide at : + - Mount hugepages -https://01.org/packet-processing/downloads + `mount -t hugetlbfs none /dev/hugepages` -A general rule of thumb for better performance is that the client -application should not be assigned the same dpdk core mask "-c" as -the vswitchd. + Note: Mount hugepages if not already mounted by default. -DPDK vhost: ------------ +### 3.2 Setup DPDK devices using VFIO -DPDK 16.04 supports two types of vhost: + - Supported with kernel version >= 3.6 + - VFIO needs support from BIOS and kernel. + - BIOS changes: -1. vhost-user -2. vhost-cuse + Enable VT-d, can be verified from `dmesg | grep -e DMAR -e IOMMU` output -Whatever type of vhost is enabled in the DPDK build specified, is the type -that will be enabled in OVS. By default, vhost-user is enabled in DPDK. -Therefore, unless vhost-cuse has been enabled in DPDK, vhost-user ports -will be enabled in OVS. -Please note that support for vhost-cuse is intended to be deprecated in OVS -in a future release. + - GRUB bootline: -DPDK vhost-user: ----------------- + Add `iommu=pt intel_iommu=on`, can be verified from `cat /proc/cmdline` output -The following sections describe the use of vhost-user 'dpdkvhostuser' ports -with OVS. + - Load modules and bind the NIC to VFIO driver -DPDK vhost-user Prerequisites: -------------------------- + ``` + modprobe vfio-pci + sudo /usr/bin/chmod a+x /dev/vfio + sudo /usr/bin/chmod 0666 /dev/vfio/* + $DPDK_DIR/tools/dpdk_nic_bind.py --bind=vfio-pci eth1 + $DPDK_DIR/tools/dpdk_nic_bind.py --status + ``` -1. DPDK 16.04 with vhost support enabled as documented in the "Building and - Installing section" + Note: If running kernels < 3.6 UIO drivers to be used, + please check [DPDK in the VM], DPDK devices using UIO section for the steps. -2. QEMU version v2.1.0+ +### 3.3 Setup OVS - QEMU v2.1.0 will suffice, but it is recommended to use v2.2.0 if providing - your VM with memory greater than 1GB due to potential issues with memory - mapping larger areas. + 1. DB creation (One time step) -Adding DPDK vhost-user ports to the Switch: --------------------------------------- + ``` + mkdir -p /usr/local/etc/openvswitch + mkdir -p /usr/local/var/run/openvswitch + rm /usr/local/etc/openvswitch/conf.db + ovsdb-tool create /usr/local/etc/openvswitch/conf.db \ + /usr/local/share/openvswitch/vswitch.ovsschema + ``` -Following the steps above to create a bridge, you can now add DPDK vhost-user -as a port to the vswitch. Unlike DPDK ring ports, DPDK vhost-user ports can -have arbitrary names, except that forward and backward slashes are prohibited -in the names. + 2. Start ovsdb-server - - For vhost-user, the name of the port type is `dpdkvhostuser` + No SSL support ``` - ovs-vsctl add-port br0 vhost-user-1 -- set Interface vhost-user-1 - type=dpdkvhostuser + ovsdb-server --remote=punix:/usr/local/var/run/openvswitch/db.sock \ + --remote=db:Open_vSwitch,Open_vSwitch,manager_options \ + --pidfile --detach ``` - This action creates a socket located at - `/usr/local/var/run/openvswitch/vhost-user-1`, which you must provide - to your VM on the QEMU command line. More instructions on this can be - found in the next section "DPDK vhost-user VM configuration" - - If you wish for the vhost-user sockets to be created in a sub-directory of - `/usr/local/var/run/openvswitch`, you may specify this directory in the - ovsdb like so: - - `./utilities/ovs-vsctl --no-wait \ - set Open_vSwitch . other_config:vhost-sock-dir=subdir` - -DPDK vhost-user VM configuration: ---------------------------------- -Follow the steps below to attach vhost-user port(s) to a VM. + SSL support -1. Configure sockets. - Pass the following parameters to QEMU to attach a vhost-user device: + ``` + ovsdb-server --remote=punix:/usr/local/var/run/openvswitch/db.sock \ + --remote=db:Open_vSwitch,Open_vSwitch,manager_options \ + --private-key=db:Open_vSwitch,SSL,private_key \ + --certificate=Open_vSwitch,SSL,certificate \ + --bootstrap-ca-cert=db:Open_vSwitch,SSL,ca_cert --pidfile --detach + ``` - ``` - -chardev socket,id=char1,path=/usr/local/var/run/openvswitch/vhost-user-1 - -netdev type=vhost-user,id=mynet1,chardev=char1,vhostforce - -device virtio-net-pci,mac=00:00:00:00:00:01,netdev=mynet1 - ``` + 3. Initialize DB (One time step) - ...where vhost-user-1 is the name of the vhost-user port added - to the switch. - Repeat the above parameters for multiple devices, changing the - chardev path and id as necessary. Note that a separate and different - chardev path needs to be specified for each vhost-user device. For - example you have a second vhost-user port named 'vhost-user-2', you - append your QEMU command line with an additional set of parameters: + ``` + ovs-vsctl --no-wait init + ``` - ``` - -chardev socket,id=char2,path=/usr/local/var/run/openvswitch/vhost-user-2 - -netdev type=vhost-user,id=mynet2,chardev=char2,vhostforce - -device virtio-net-pci,mac=00:00:00:00:00:02,netdev=mynet2 - ``` + 4. Start vswitchd -2. Configure huge pages. - QEMU must allocate the VM's memory on hugetlbfs. vhost-user ports access - a virtio-net device's virtual rings and packet buffers mapping the VM's - physical memory on hugetlbfs. To enable vhost-user ports to map the VM's - memory into their process address space, pass the following paramters - to QEMU: + DPDK configuration arguments can be passed to vswitchd via Open_vSwitch + 'other_config' column. The important configuration options are listed below. + Defaults will be provided for all values not explicitly set. Refer + ovs-vswitchd.conf.db(5) for additional information on configuration options. - ``` - -object memory-backend-file,id=mem,size=4096M,mem-path=/dev/hugepages, - share=on - -numa node,memdev=mem -mem-prealloc - ``` + * dpdk-init + Specifies whether OVS should initialize and support DPDK ports. This is + a boolean, and defaults to false. -3. Optional: Enable multiqueue support - The vhost-user interface must be configured in Open vSwitch with the - desired amount of queues with: + * dpdk-lcore-mask + Specifies the CPU cores on which dpdk lcore threads should be spawned and + expects hex string (eg '0x123'). - ``` - ovs-vsctl set Interface vhost-user-2 options:n_rxq=<requested queues> - ``` + * dpdk-socket-mem + Comma separated list of memory to pre-allocate from hugepages on specific + sockets. - QEMU needs to be configured as well. - The $q below should match the queues requested in OVS (if $q is more, - packets will not be received). - The $v is the number of vectors, which is '$q x 2 + 2'. + * dpdk-hugepage-dir + Directory where hugetlbfs is mounted - ``` - -chardev socket,id=char2,path=/usr/local/var/run/openvswitch/vhost-user-2 - -netdev type=vhost-user,id=mynet2,chardev=char2,vhostforce,queues=$q - -device virtio-net-pci,mac=00:00:00:00:00:02,netdev=mynet2,mq=on,vectors=$v - ``` + * vhost-sock-dir + Option to set the path to the vhost_user unix socket files. - If one wishes to use multiple queues for an interface in the guest, the - driver in the guest operating system must be configured to do so. It is - recommended that the number of queues configured be equal to '$q'. + NOTE: Changing any of these options requires restarting the ovs-vswitchd + application. - For example, this can be done for the Linux kernel virtio-net driver with: + Open vSwitch can be started as normal. DPDK will be initialized as long + as the dpdk-init option has been set to 'true'. - ``` - ethtool -L <DEV> combined <$q> - ``` + ``` + export DB_SOCK=/usr/local/var/run/openvswitch/db.sock + ovs-vsctl --no-wait set Open_vSwitch . other_config:dpdk-init=true + ovs-vswitchd unix:$DB_SOCK --pidfile --detach + ``` - A note on the command above: + If allocated more than one GB hugepage (as for IVSHMEM), set amount and + use NUMA node 0 memory. For details on using ivshmem with DPDK, refer to + [OVS Testcases]. - `-L`: Changes the numbers of channels of the specified network device + ``` + ovs-vsctl --no-wait set Open_vSwitch . other_config:dpdk-socket-mem="1024,0" + ovs-vswitchd unix:$DB_SOCK --pidfile --detach + ``` - `combined`: Changes the number of multi-purpose channels. + To better scale the work loads across cores, Multiple pmd threads can be + created and pinned to CPU cores by explicity specifying pmd-cpu-mask. + eg: To spawn 2 pmd threads and pin them to cores 1, 2 -DPDK vhost-cuse: ----------------- + ``` + ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=6 + ``` -The following sections describe the use of vhost-cuse 'dpdkvhostcuse' ports -with OVS. + 5. Create bridge & add DPDK devices -DPDK vhost-cuse Prerequisites: -------------------------- + create a bridge with datapath_type "netdev" in the configuration database -1. DPDK 16.04 with vhost support enabled as documented in the "Building and - Installing section" - As an additional step, you must enable vhost-cuse in DPDK by setting the - following additional flag in `config/common_base`: + `ovs-vsctl add-br br0 -- set bridge br0 datapath_type=netdev` - `CONFIG_RTE_LIBRTE_VHOST_USER=n` + Now you can add DPDK devices. OVS expects DPDK device names to start with + "dpdk" and end with a portid. vswitchd should print (in the log file) the + number of dpdk devices found. - Following this, rebuild DPDK as per the instructions in the "Building and - Installing" section. Finally, rebuild OVS as per step 3 in the "Building - and Installing" section - OVS will detect that DPDK has vhost-cuse libraries - compiled and in turn will enable support for it in the switch and disable - vhost-user support. + ``` + ovs-vsctl add-port br0 dpdk0 -- set Interface dpdk0 type=dpdk + ovs-vsctl add-port br0 dpdk1 -- set Interface dpdk1 type=dpdk + ``` -2. Insert the Cuse module: + After the DPDK ports get added to switch, a polling thread continuously polls + DPDK devices and consumes 100% of the core as can be checked from 'top' and 'ps' cmds. - `modprobe cuse` + ``` + top -H + ps -eLo pid,psr,comm | grep pmd + ``` -3. Build and insert the `eventfd_link` module: + Note: creating bonds of DPDK interfaces is slightly different to creating + bonds of system interfaces. For DPDK, the interface type must be explicitly + set, for example: ``` - cd $DPDK_DIR/lib/librte_vhost/eventfd_link/ - make - insmod $DPDK_DIR/lib/librte_vhost/eventfd_link.ko + ovs-vsctl add-bond br0 dpdkbond dpdk0 dpdk1 -- set Interface dpdk0 type=dpdk -- set Interface dpdk1 type=dpdk ``` -4. QEMU version v2.1.0+ + 6. PMD thread statistics - vhost-cuse will work with QEMU v2.1.0 and above, however it is recommended to - use v2.2.0 if providing your VM with memory greater than 1GB due to potential - issues with memory mapping larger areas. - Note: QEMU v1.6.2 will also work, with slightly different command line parameters, - which are specified later in this document. + ``` + # Check current stats + ovs-appctl dpif-netdev/pmd-stats-show -Adding DPDK vhost-cuse ports to the Switch: --------------------------------------- + # Show port/rxq assignment + ovs-appctl dpif-netdev/pmd-rxq-show -Following the steps above to create a bridge, you can now add DPDK vhost-cuse -as a port to the vswitch. Unlike DPDK ring ports, DPDK vhost-cuse ports can have -arbitrary names. + # Clear previous stats + ovs-appctl dpif-netdev/pmd-stats-clear + ``` - - For vhost-cuse, the name of the port type is `dpdkvhostcuse` + 7. Stop vswitchd & Delete bridge ``` - ovs-vsctl add-port br0 vhost-cuse-1 -- set Interface vhost-cuse-1 - type=dpdkvhostcuse + ovs-appctl -t ovs-vswitchd exit + ovs-appctl -t ovsdb-server exit + ovs-vsctl del-br br0 ``` - When attaching vhost-cuse ports to QEMU, the name provided during the - add-port operation must match the ifname parameter on the QEMU command - line. More instructions on this can be found in the next section. +## <a name="builddpdk"></a> 4. DPDK in the VM -DPDK vhost-cuse VM configuration: ---------------------------------- +DPDK 'testpmd' application can be run in the Guest VM for high speed +packet forwarding between vhostuser ports. DPDK and testpmd application +has to be compiled on the guest VM. Below are the steps for setting up +the testpmd application in the VM. More information on the vhostuser ports +can be found in [Vhost Walkthrough]. - vhost-cuse ports use a Linux* character device to communicate with QEMU. - By default it is set to `/dev/vhost-net`. It is possible to reuse this - standard device for DPDK vhost, which makes setup a little simpler but it - is better practice to specify an alternative character device in order to - avoid any conflicts if kernel vhost is to be used in parallel. + * Instantiate the Guest -1. This step is only needed if using an alternative character device. + ``` + Qemu version >= 2.2.0 - The new character device filename must be specified in the ovsdb: + export VM_NAME=Centos-vm + export GUEST_MEM=3072M + export QCOW2_IMAGE=/root/CentOS7_x86_64.qcow2 + export VHOST_SOCK_DIR=/usr/local/var/run/openvswitch - `./utilities/ovs-vsctl --no-wait set Open_vSwitch . \ - other_config:cuse-dev-name=my-vhost-net` + qemu-system-x86_64 -name $VM_NAME -cpu host -enable-kvm -m $GUEST_MEM -object memory-backend-file,id=mem,size=$GUEST_MEM,mem-path=/dev/hugepages,share=on -numa node,memdev=mem -mem-prealloc -smp sockets=1,cores=2 -drive file=$QCOW2_IMAGE -chardev socket,id=char0,path=$VHOST_SOCK_DIR/dpdkvhostuser0 -netdev type=vhost-user,id=mynet1,chardev=char0,vhostforce -device virtio-net-pci,mac=00:00:00:00:00:01,netdev=mynet1,mrg_rxbuf=off -chardev socket,id=char1,path=$VHOST_SOCK_DIR/dpdkvhostuser1 -netdev type=vhost-user,id=mynet2,chardev=char1,vhostforce -device virtio-net-pci,mac=00:00:00:00:00:02,netdev=mynet2,mrg_rxbuf=off --nographic -snapshot + ``` - In the example above, the character device to be used will be - `/dev/my-vhost-net`. + * Download the DPDK Srcs to VM and build DPDK -2. This step is only needed if reusing the standard character device. It will - conflict with the kernel vhost character device so the user must first - remove it. + ``` + cd /root/dpdk/ + wget http://dpdk.org/browse/dpdk/snapshot/dpdk-16.04.zip + unzip dpdk-16.04.zip + export DPDK_DIR=/root/dpdk/dpdk-16.04 + export DPDK_TARGET=x86_64-native-linuxapp-gcc + export DPDK_BUILD=$DPDK_DIR/$DPDK_TARGET + cd $DPDK_DIR + make install T=$DPDK_TARGET DESTDIR=install + ``` - `rm -rf /dev/vhost-net` + * Build the test-pmd application -3a. Configure virtio-net adaptors: - The following parameters must be passed to the QEMU binary: + ``` + cd app/test-pmd + export RTE_SDK=$DPDK_DIR + export RTE_TARGET=$DPDK_TARGET + make + ``` - ``` - -netdev tap,id=<id>,script=no,downscript=no,ifname=<name>,vhost=on - -device virtio-net-pci,netdev=net1,mac=<mac> - ``` + * Setup Huge pages and DPDK devices using UIO - Repeat the above parameters for multiple devices. + ``` + sysctl vm.nr_hugepages=1024 + mkdir -p /dev/hugepages + mount -t hugetlbfs hugetlbfs /dev/hugepages (only if not already mounted) + modprobe uio + insmod $DPDK_BUILD/kmod/igb_uio.ko + $DPDK_DIR/tools/dpdk_nic_bind.py --status + $DPDK_DIR/tools/dpdk_nic_bind.py -b igb_uio 00:03.0 00:04.0 + ``` - The DPDK vhost library will negiotiate its own features, so they - need not be passed in as command line params. Note that as offloads are - disabled this is the equivalent of setting: + vhost ports pci ids can be retrieved using `lspci | grep Ethernet` cmd. - `csum=off,gso=off,guest_tso4=off,guest_tso6=off,guest_ecn=off` +## <a name="ovstc"></a> 5. OVS Testcases -3b. If using an alternative character device. It must be also explicitly - passed to QEMU using the `vhostfd` argument: + Below are few testcases and the list of steps to be followed. - ``` - -netdev tap,id=<id>,script=no,downscript=no,ifname=<name>,vhost=on, - vhostfd=<open_fd> - -device virtio-net-pci,netdev=net1,mac=<mac> - ``` +### 5.1 PHY-PHY + + The steps (1-5) in 3.3 section will create & initialize DB, start vswitchd and also + add DPDK devices to bridge 'br0'. - The open file descriptor must be passed to QEMU running as a child - process. This could be done with a simple python script. + 1. Add Test flows to forward packets betwen DPDK port 0 and port 1 ``` - #!/usr/bin/python - fd = os.open("/dev/usvhost", os.O_RDWR) - subprocess.call("qemu-system-x86_64 .... -netdev tap,id=vhostnet0,\ - vhost=on,vhostfd=" + fd +"...", shell=True) - - Alternatively the `qemu-wrap.py` script can be used to automate the - requirements specified above and can be used in conjunction with libvirt if - desired. See the "DPDK vhost VM configuration with QEMU wrapper" section - below. - -4. Configure huge pages: - QEMU must allocate the VM's memory on hugetlbfs. Vhost ports access a - virtio-net device's virtual rings and packet buffers mapping the VM's - physical memory on hugetlbfs. To enable vhost-ports to map the VM's - memory into their process address space, pass the following parameters - to QEMU: - - `-object memory-backend-file,id=mem,size=4096M,mem-path=/dev/hugepages, - share=on -numa node,memdev=mem -mem-prealloc` - - Note: For use with an earlier QEMU version such as v1.6.2, use the - following to configure hugepages instead: - - `-mem-path /dev/hugepages -mem-prealloc` - -DPDK vhost-cuse VM configuration with QEMU wrapper: ---------------------------------------------------- -The QEMU wrapper script automatically detects and calls QEMU with the -necessary parameters. It performs the following actions: - - * Automatically detects the location of the hugetlbfs and inserts this - into the command line parameters. - * Automatically open file descriptors for each virtio-net device and - inserts this into the command line parameters. - * Calls QEMU passing both the command line parameters passed to the - script itself and those it has auto-detected. - -Before use, you **must** edit the configuration parameters section of the -script to point to the correct emulator location and set additional -settings. Of these settings, `emul_path` and `us_vhost_path` **must** be -set. All other settings are optional. - -To use directly from the command line simply pass the wrapper some of the -QEMU parameters: it will configure the rest. For example: - -``` -qemu-wrap.py -cpu host -boot c -hda <disk image> -m 4096 -smp 4 - --enable-kvm -nographic -vnc none -net none -netdev tap,id=net1, - script=no,downscript=no,ifname=if1,vhost=on -device virtio-net-pci, - netdev=net1,mac=00:00:00:00:00:01 -``` - -DPDK vhost-cuse VM configuration with libvirt: ----------------------------------------------- - -If you are using libvirt, you must enable libvirt to access the character -device by adding it to controllers cgroup for libvirtd using the following -steps. - - 1. In `/etc/libvirt/qemu.conf` add/edit the following lines: - - ``` - 1) clear_emulator_capabilities = 0 - 2) user = "root" - 3) group = "root" - 4) cgroup_device_acl = [ - "/dev/null", "/dev/full", "/dev/zero", - "/dev/random", "/dev/urandom", - "/dev/ptmx", "/dev/kvm", "/dev/kqemu", - "/dev/rtc", "/dev/hpet", "/dev/net/tun", - "/dev/<my-vhost-device>", - "/dev/hugepages"] - ``` - - <my-vhost-device> refers to "vhost-net" if using the `/dev/vhost-net` - device. If you have specificed a different name in the database - using the "other_config:cuse-dev-name" parameter, please specify that - filename instead. - - 2. Disable SELinux or set to permissive mode - - 3. Restart the libvirtd process - For example, on Fedora: - - `systemctl restart libvirtd.service` - -After successfully editing the configuration, you may launch your -vhost-enabled VM. The XML describing the VM can be configured like so -within the <qemu:commandline> section: - - 1. Set up shared hugepages: + # Clear current flows + ovs-ofctl del-flows br0 - ``` - <qemu:arg value='-object'/> - <qemu:arg value='memory-backend-file,id=mem,size=4096M,mem-path=/dev/hugepages,share=on'/> - <qemu:arg value='-numa'/> - <qemu:arg value='node,memdev=mem'/> - <qemu:arg value='-mem-prealloc'/> - ``` + # Add flows between port 1 (dpdk0) to port 2 (dpdk1) + ovs-ofctl add-flow br0 in_port=1,action=output:2 + ovs-ofctl add-flow br0 in_port=2,action=output:1 + ``` - 2. Set up your tap devices: +### 5.2 PHY-VM-PHY [VHOST LOOPBACK] - ``` - <qemu:arg value='-netdev'/> - <qemu:arg value='type=tap,id=net1,script=no,downscript=no,ifname=vhost0,vhost=on'/> - <qemu:arg value='-device'/> - <qemu:arg value='virtio-net-pci,netdev=net1,mac=00:00:00:00:00:01'/> - ``` + The steps (1-5) in 3.3 section will create & initialize DB, start vswitchd and also + add DPDK devices to bridge 'br0'. - Repeat for as many devices as are desired, modifying the id, ifname - and mac as necessary. + 1. Add dpdkvhostuser ports to bridge 'br0'. More information on the dpdkvhostuser ports + can be found in [Vhost Walkthrough]. - Again, if you are using an alternative character device (other than - `/dev/vhost-net`), please specify the file descriptor like so: + ``` + ovs-vsctl add-port br0 dpdkvhostuser0 -- set Interface dpdkvhostuser0 type=dpdkvhostuser + ovs-vsctl add-port br0 dpdkvhostuser1 -- set Interface dpdkvhostuser1 type=dpdkvhostuser + ``` - `<qemu:arg value='type=tap,id=net3,script=no,downscript=no,ifname=vhost0,vhost=on,vhostfd=<open_fd>'/>` + 2. Add Test flows to forward packets betwen DPDK devices and VM ports - Where <open_fd> refers to the open file descriptor of the character device. - Instructions of how to retrieve the file descriptor can be found in the - "DPDK vhost VM configuration" section. - Alternatively, the process is automated with the qemu-wrap.py script, - detailed in the next section. + ``` + # Clear current flows + ovs-ofctl del-flows br0 -Now you may launch your VM using virt-manager, or like so: + # Add flows + ovs-ofctl add-flow br0 in_port=1,action=output:3 + ovs-ofctl add-flow br0 in_port=3,action=output:1 + ovs-ofctl add-flow br0 in_port=4,action=output:2 + ovs-ofctl add-flow br0 in_port=2,action=output:4 - `virsh create my_vhost_vm.xml` + # Dump flows + ovs-ofctl dump-flows br0 + ``` -DPDK vhost-cuse VM configuration with libvirt and QEMU wrapper: ----------------------------------------------------------- + 3. Instantiate Guest VM using Qemu cmdline -To use the qemu-wrapper script in conjuntion with libvirt, follow the -steps in the previous section before proceeding with the following steps: + Guest Configuration - 1. Place `qemu-wrap.py` in libvirtd's binary search PATH ($PATH) - Ideally in the same directory that the QEMU binary is located. + ``` + | configuration | values | comments + |----------------------|--------|----------------- + | qemu version | 2.2.0 | + | qemu thread affinity | core 5 | taskset 0x20 + | memory | 4GB | - + | cores | 2 | - + | Qcow2 image | CentOS7| - + | mrg_rxbuf | off | - + ``` - 2. Ensure that the script has the same owner/group and file permissions - as the QEMU binary. + Instantiate Guest - 3. Update the VM xml file using "virsh edit VM.xml" + ``` + export VM_NAME=vhost-vm + export GUEST_MEM=3072M + export QCOW2_IMAGE=/root/CentOS7_x86_64.qcow2 + export VHOST_SOCK_DIR=/usr/local/var/run/openvswitch - 1. Set the VM to use the launch script. - Set the emulator path contained in the `<emulator><emulator/>` tags. - For example, replace: + taskset 0x20 qemu-system-x86_64 -name $VM_NAME -cpu host -enable-kvm -m $GUEST_MEM -object memory-backend-file,id=mem,size=$GUEST_MEM,mem-path=/dev/hugepages,share=on -numa node,memdev=mem -mem-prealloc -smp sockets=1,cores=2 -drive file=$QCOW2_IMAGE -chardev socket,id=char0,path=$VHOST_SOCK_DIR/dpdkvhostuser0 -netdev type=vhost-user,id=mynet1,chardev=char0,vhostforce -device virtio-net-pci,mac=00:00:00:00:00:01,netdev=mynet1,mrg_rxbuf=off -chardev socket,id=char1,path=$VHOST_SOCK_DIR/dpdkvhostuser1 -netdev type=vhost-user,id=mynet2,chardev=char1,vhostforce -device virtio-net-pci,mac=00:00:00:00:00:02,netdev=mynet2,mrg_rxbuf=off --nographic -snapshot + ``` - `<emulator>/usr/bin/qemu-kvm<emulator/>` + 4. Guest VM using libvirt - with: + The below is a simple xml configuration of 'demovm' guest that can be instantiated + using 'virsh'. The guest uses a pair of vhostuser port and boots with 4GB RAM and 2 cores. + More information can be found in [Vhost Walkthrough]. - `<emulator>/usr/bin/qemu-wrap.py<emulator/>` + ``` + <domain type='kvm'> + <name>demovm</name> + <uuid>4a9b3f53-fa2a-47f3-a757-dd87720d9d1d</uuid> + <memory unit='KiB'>4194304</memory> + <currentMemory unit='KiB'>4194304</currentMemory> + <memoryBacking> + <hugepages> + <page size='2' unit='M' nodeset='0'/> + </hugepages> + </memoryBacking> + <vcpu placement='static'>2</vcpu> + <cputune> + <shares>4096</shares> + <vcpupin vcpu='0' cpuset='4'/> + <vcpupin vcpu='1' cpuset='5'/> + <emulatorpin cpuset='4,5'/> + </cputune> + <os> + <type arch='x86_64' machine='pc'>hvm</type> + <boot dev='hd'/> + </os> + <features> + <acpi/> + <apic/> + </features> + <cpu mode='host-model'> + <model fallback='allow'/> + <topology sockets='2' cores='1' threads='1'/> + <numa> + <cell id='0' cpus='0-1' memory='4194304' unit='KiB' memAccess='shared'/> + </numa> + </cpu> + <on_poweroff>destroy</on_poweroff> + <on_reboot>restart</on_reboot> + <on_crash>destroy</on_crash> + <devices> + <emulator>/usr/bin/qemu-kvm</emulator> + <disk type='file' device='disk'> + <driver name='qemu' type='qcow2' cache='none'/> + <source file='/root/CentOS7_x86_64.qcow2'/> + <target dev='vda' bus='virtio'/> + </disk> + <disk type='dir' device='disk'> + <driver name='qemu' type='fat'/> + <source dir='/usr/src/dpdk-16.04'/> + <target dev='vdb' bus='virtio'/> + <readonly/> + </disk> + <interface type='vhostuser'> + <mac address='00:00:00:00:00:01'/> + <source type='unix' path='/usr/local/var/run/openvswitch/dpdkvhostuser0' mode='client'/> + <model type='virtio'/> + <driver queues='2'> + <host mrg_rxbuf='off'/> + </driver> + </interface> + <interface type='vhostuser'> + <mac address='00:00:00:00:00:02'/> + <source type='unix' path='/usr/local/var/run/openvswitch/dpdkvhostuser1' mode='client'/> + <model type='virtio'/> + <driver queues='2'> + <host mrg_rxbuf='off'/> + </driver> + </interface> + <serial type='pty'> + <target port='0'/> + </serial> + <console type='pty'> + <target type='serial' port='0'/> + </console> + </devices> + </domain> + ``` - 4. Edit the Configuration Parameters section of the script to point to - the correct emulator location and set any additional options. If you are - using a alternative character device name, please set "us_vhost_path" to the - location of that device. The script will automatically detect and insert - the correct "vhostfd" value in the QEMU command line arguments. + 5. DPDK Packet forwarding in Guest VM - 5. Use virt-manager to launch the VM + To accomplish this, DPDK and testpmd application have to be first compiled + on the VM and the steps are listed in [DPDK in the VM]. -Running ovs-vswitchd with DPDK backend inside a VM --------------------------------------------------- + * Run test-pmd application -Please note that additional configuration is required if you want to run -ovs-vswitchd with DPDK backend inside a QEMU virtual machine. Ovs-vswitchd -creates separate DPDK TX queues for each CPU core available. This operation -fails inside QEMU virtual machine because, by default, VirtIO NIC provided -to the guest is configured to support only single TX queue and single RX -queue. To change this behavior, you need to turn on 'mq' (multiqueue) -property of all virtio-net-pci devices emulated by QEMU and used by DPDK. -You may do it manually (by changing QEMU command line) or, if you use Libvirt, -by adding the following string: + ``` + cd $DPDK_DIR/app/test-pmd; + ./testpmd -c 0x3 -n 4 --socket-mem 1024 -- --burst=64 -i --txqflags=0xf00 --disable-hw-vlan + set fwd mac_retry + start + ``` -`<driver name='vhost' queues='N'/>` + * Bind vNIC back to kernel once the test is completed. -to <interface> sections of all network devices used by DPDK. Parameter 'N' -determines how many queues can be used by the guest. + ``` + $DPDK_DIR/tools/dpdk_nic_bind.py --bind=virtio-pci 0000:00:03.0 + $DPDK_DIR/tools/dpdk_nic_bind.py --bind=virtio-pci 0000:00:04.0 + ``` + Note: Appropriate PCI IDs to be passed in above example. The PCI IDs can be + retrieved using '$DPDK_DIR/tools/dpdk_nic_bind.py --status' cmd. -Restrictions: -------------- +### 5.3 PHY-VM-PHY [IVSHMEM] - - Work with 1500 MTU, needs few changes in DPDK lib to fix this issue. - - Currently DPDK port does not make use any offload functionality. - - DPDK-vHost support works with 1G huge pages. + The steps for setup of IVSHMEM are covered in section 5.2(PVP - IVSHMEM) + of [OVS Testcases] in ADVANCED install guide. - ivshmem: - - If you run Open vSwitch with smaller page sizes (e.g. 2MB), you may be - unable to share any rings or mempools with a virtual machine. - This is because the current implementation of ivshmem works by sharing - a single 1GB huge page from the host operating system to any guest - operating system through the Qemu ivshmem device. When using smaller - page sizes, multiple pages may be required to hold the ring descriptors - and buffer pools. The Qemu ivshmem device does not allow you to share - multiple file descriptors to the guest operating system. However, if you - want to share dpdkr rings with other processes on the host, you can do - this with smaller page sizes. +## <a name="ovslimits"></a> 6. Limitations - Platform and Network Interface: - - By default with DPDK 16.04, a maximum of 64 TX queues can be used with an - Intel XL710 Network Interface on a platform with more than 64 logical - cores. If a user attempts to add an XL710 interface as a DPDK port type to - a system as described above, an error will be reported that initialization - failed for the 65th queue. OVS will then roll back to the previous - successful queue initialization and use that value as the total number of - TX queues available with queue locking. If a user wishes to use more than - 64 queues and avoid locking, then the - `CONFIG_RTE_LIBRTE_I40E_QUEUE_NUM_PER_PF` config parameter in DPDK must be - increased to the desired number of queues. Both DPDK and OVS must be - recompiled for this change to take effect. + - Supports MTU size 1500, MTU setting for DPDK netdevs will be in future OVS release. + - Currently DPDK ports does not use HW offload functionality. Bug Reporting: -------------- Please report problems to b...@openvswitch.org. -[INSTALL.userspace.md]:INSTALL.userspace.md + +[DPDK requirements]: http://dpdk.org/doc/guides/linux_gsg/sys_reqs.html +[Download DPDK]: http://dpdk.org/browse/dpdk/refs/ +[Download OVS]: http://openvswitch.org/releases/ +[DPDK Supported NICs]: http://dpdk.org/doc/nics +[Build Requirements]: https://github.com/openvswitch/ovs/blob/master/INSTALL.md#build-requirements +[INSTALL.DPDK-ADVANCED.md]: INSTALL.DPDK-ADVANCED.md +[OVS Testcases]: INSTALL.DPDK-ADVANCED.md#ovstc +[Vhost Walkthrough]: INSTALL.DPDK-ADVANCED.md#vhost +[DPDK in the VM]: INSTALL.DPDK.md#builddpdk [INSTALL.md]:INSTALL.md -[DPDK Linux GSG]: http://www.dpdk.org/doc/guides/linux_gsg/build_dpdk.html#binding-and-unbinding-network-ports-to-from-the-igb-uioor-vfio-modules -[DPDK Docs]: http://dpdk.org/doc +[INSTALL.Fedora.md]:INSTALL.Fedora.md +[INSTALL.RHEL.md]:INSTALL.RHEL.md +[INSTALL.Debian.md]:INSTALL.Debian.md -- 2.4.11 _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
