From: Junyu Jiang Date: Wed, 25 Mar 2020 06:32:47 +0000 (+0000) Subject: doc: add user guide for VMDq example X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=9a82259d5ddd6e73f1369ba6fb63cab251efa96d;p=dpdk.git doc: add user guide for VMDq example Currently, there is no documentation for VMDq example, this path added the user guide for VMDq. Signed-off-by: Junyu Jiang Reviewed-by: Jingjing Wu --- diff --git a/MAINTAINERS b/MAINTAINERS index e18b2dba7e..005f430fad 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1594,5 +1594,6 @@ M: Xiaoyun Li F: examples/tep_termination/ F: examples/vmdq/ +F: doc/guides/sample_app_ug/vmdq_forwarding.rst F: examples/vmdq_dcb/ F: doc/guides/sample_app_ug/vmdq_dcb_forwarding.rst diff --git a/doc/guides/sample_app_ug/index.rst b/doc/guides/sample_app_ug/index.rst index ac34451479..4b16dd161e 100644 --- a/doc/guides/sample_app_ug/index.rst +++ b/doc/guides/sample_app_ug/index.rst @@ -40,6 +40,7 @@ Sample Applications User Guides timer packet_ordering vmdq_dcb_forwarding + vmdq_forwarding vhost vhost_blk vhost_crypto diff --git a/doc/guides/sample_app_ug/vmdq_forwarding.rst b/doc/guides/sample_app_ug/vmdq_forwarding.rst new file mode 100644 index 0000000000..d2585687bb --- /dev/null +++ b/doc/guides/sample_app_ug/vmdq_forwarding.rst @@ -0,0 +1,208 @@ +.. SPDX-License-Identifier: BSD-3-Clause + Copyright(c) 2020 Intel Corporation. + +VMDq Forwarding Sample Application +========================================== + +The VMDq Forwarding sample application is a simple example of packet processing using the DPDK. +The application performs L2 forwarding using VMDq to divide the incoming traffic into queues. +The traffic splitting is performed in hardware by the VMDq feature of the Intel® 82599 and X710/XL710 Ethernet Controllers. + +Overview +-------- + +This sample application can be used as a starting point for developing a new application that is based on the DPDK and +uses VMDq for traffic partitioning. + +VMDq filters split the incoming packets up into different "pools" - each with its own set of RX queues - based upon +the MAC address and VLAN ID within the VLAN tag of the packet. + +All traffic is read from a single incoming port and output on another port, without any processing being performed. +With Intel® 82599 NIC, for example, the traffic is split into 128 queues on input, where each thread of the application reads from +multiple queues. When run with 8 threads, that is, with the -c FF option, each thread receives and forwards packets from 16 queues. + +As supplied, the sample application configures the VMDq feature to have 32 pools with 4 queues each. +The Intel® 82599 10 Gigabit Ethernet Controller NIC also supports the splitting of traffic into 16 pools of 2 queues. +While the Intel® X710 or XL710 Ethernet Controller NICs support many configurations of VMDq pools of 4 or 8 queues each. +And queues numbers for each VMDq pool can be changed by setting CONFIG_RTE_LIBRTE_I40E_QUEUE_NUM_PER_VM +in config/common_* file. +The nb-pools parameter can be passed on the command line, after the EAL parameters: + +.. code-block:: console + + ./build/vmdq_app [EAL options] -- -p PORTMASK --nb-pools NP + +where, NP can be 8, 16 or 32. + +In Linux* user space, the application can display statistics with the number of packets received on each queue. +To have the application display the statistics, send a SIGHUP signal to the running application process. + +The VMDq Forwarding sample application is in many ways simpler than the L2 Forwarding application +(see :doc:`l2_forward_real_virtual`) +as it performs unidirectional L2 forwarding of packets from one port to a second port. +No command-line options are taken by this application apart from the standard EAL command-line options. + +Compiling the Application +------------------------- + +To compile the sample application see :doc:`compiling`. + +The application is located in the ``vmdq`` sub-directory. + +Running the Application +----------------------- + +To run the example in a Linux environment: + +.. code-block:: console + + user@target:~$ ./build/vmdq_app -l 0-3 -n 4 -- -p 0x3 --nb-pools 16 + +Refer to the *DPDK Getting Started Guide* for general information on running applications and +the Environment Abstraction Layer (EAL) options. + +Explanation +----------- + +The following sections provide some explanation of the code. + +Initialization +~~~~~~~~~~~~~~ + +The EAL, driver and PCI configuration is performed largely as in the L2 Forwarding sample application, +as is the creation of the mbuf pool. +See :doc:`l2_forward_real_virtual`. +Where this example application differs is in the configuration of the NIC port for RX. + +The VMDq hardware feature is configured at port initialization time by setting the appropriate values in the +rte_eth_conf structure passed to the rte_eth_dev_configure() API. +Initially in the application, +a default structure is provided for VMDq configuration to be filled in later by the application. + +.. code-block:: c + + /* empty vmdq configuration structure. Filled in programmatically */ + static const struct rte_eth_conf vmdq_conf_default = { + .rxmode = { + .mq_mode = ETH_MQ_RX_VMDQ_ONLY, + .split_hdr_size = 0, + }, + + .txmode = { + .mq_mode = ETH_MQ_TX_NONE, + }, + .rx_adv_conf = { + /* + * should be overridden separately in code with + * appropriate values + */ + .vmdq_rx_conf = { + .nb_queue_pools = ETH_8_POOLS, + .enable_default_pool = 0, + .default_pool = 0, + .nb_pool_maps = 0, + .pool_map = {{0, 0},}, + }, + }, + }; + +The get_eth_conf() function fills in an rte_eth_conf structure with the appropriate values, +based on the global vlan_tags array. +For the VLAN IDs, each one can be allocated to possibly multiple pools of queues. +For destination MAC, each VMDq pool will be assigned with a MAC address. In this sample, each VMDq pool +is assigned to the MAC like 52:54:00:12::, that is, +the MAC of VMDq pool 2 on port 1 is 52:54:00:12:01:02. + +.. code-block:: c + + const uint16_t vlan_tags[] = { + 0, 1, 2, 3, 4, 5, 6, 7, + 8, 9, 10, 11, 12, 13, 14, 15, + 16, 17, 18, 19, 20, 21, 22, 23, + 24, 25, 26, 27, 28, 29, 30, 31, + 32, 33, 34, 35, 36, 37, 38, 39, + 40, 41, 42, 43, 44, 45, 46, 47, + 48, 49, 50, 51, 52, 53, 54, 55, + 56, 57, 58, 59, 60, 61, 62, 63, + }; + + /* pool mac addr template, pool mac addr is like: 52 54 00 12 port# pool# */ + static struct rte_ether_addr pool_addr_template = { + .addr_bytes = {0x52, 0x54, 0x00, 0x12, 0x00, 0x00} + }; + + /* + * Builds up the correct configuration for vmdq based on the vlan tags array + * given above, and determine the queue number and pool map number according to + * valid pool number + */ + static inline int + get_eth_conf(struct rte_eth_conf *eth_conf, uint32_t num_pools) + { + struct rte_eth_vmdq_rx_conf conf; + unsigned i; + + conf.nb_queue_pools = (enum rte_eth_nb_pools)num_pools; + conf.nb_pool_maps = num_pools; + conf.enable_default_pool = 0; + conf.default_pool = 0; /* set explicit value, even if not used */ + + for (i = 0; i < conf.nb_pool_maps; i++) { + conf.pool_map[i].vlan_id = vlan_tags[i]; + conf.pool_map[i].pools = (1UL << (i % num_pools)); + } + + (void)(rte_memcpy(eth_conf, &vmdq_conf_default, sizeof(*eth_conf))); + (void)(rte_memcpy(ð_conf->rx_adv_conf.vmdq_rx_conf, &conf, + sizeof(eth_conf->rx_adv_conf.vmdq_rx_conf))); + return 0; + } + + ...... + + /* + * Set mac for each pool. + * There is no default mac for the pools in i40. + * Removes this after i40e fixes this issue. + */ + for (q = 0; q < num_pools; q++) { + struct rte_ether_addr mac; + mac = pool_addr_template; + mac.addr_bytes[4] = port; + mac.addr_bytes[5] = q; + printf("Port %u vmdq pool %u set mac %02x:%02x:%02x:%02x:%02x:%02x\n", + port, q, + mac.addr_bytes[0], mac.addr_bytes[1], + mac.addr_bytes[2], mac.addr_bytes[3], + mac.addr_bytes[4], mac.addr_bytes[5]); + retval = rte_eth_dev_mac_addr_add(port, &mac, + q + vmdq_pool_base); + if (retval) { + printf("mac addr add failed at pool %d\n", q); + return retval; + } + } + +Once the network port has been initialized using the correct VMDq values, +the initialization of the port's RX and TX hardware rings is performed similarly to that +in the L2 Forwarding sample application. +See :doc:`l2_forward_real_virtual` for more information. + +Statistics Display +~~~~~~~~~~~~~~~~~~ + +When run in a Linux environment, +the VMDq Forwarding sample application can display statistics showing the number of packets read from each RX queue. +This is provided by way of a signal handler for the SIGHUP signal, +which simply prints to standard output the packet counts in grid form. +Each row of the output is a single pool with the columns being the queue number within that pool. + +To generate the statistics output, use the following command: + +.. code-block:: console + + user@host$ sudo killall -HUP vmdq_app + +Please note that the statistics output will appear on the terminal where the vmdq_app is running, +rather than the terminal from which the HUP signal was sent. +