d/numam-dpdk
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
4690a6114f
numam-dpdk/doc/guides/sample_app_ug/flow_classify.rst
Ciara Power e2a94f9ad3 doc: remove references to make from apps guide 
While make has been deprecated for DPDK, it's still applicable for
some example apps to be built standalone, this patch adjusts the
guides to take that into consideration.

Signed-off-by: Ciara Power <ciara.power@intel.com>
Acked-by: Nicolas Chautru <nicolas.chautru@intel.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
2020-10-22 22:54:05 +02:00

545 lines
17 KiB
ReStructuredText
Raw Blame History

.. SPDX-License-Identifier: BSD-3-Clause
Copyright(c) 2017 Intel Corporation.
Flow Classify Sample Application
================================
The Flow Classify sample application is based on the simple *skeleton* example
of a forwarding application.
It is intended as a demonstration of the basic components of a DPDK forwarding
application which uses the Flow Classify library API's.
Please refer to the
:doc:`../prog_guide/flow_classify_lib`
for more information.
Compiling the Application
-------------------------
To compile the sample application see :doc:`compiling`.
The application is located in the ``flow_classify`` sub-directory.
Running the Application
-----------------------
To run the example in a ``linux`` environment:
.. code-block:: console
./<build_dir>/examples/dpdk-flow_classify -c 4 -n 4 -- /
--rule_ipv4="../ipv4_rules_file.txt"
Please refer to the *DPDK Getting Started Guide*, section
:doc:`../linux_gsg/build_sample_apps`
for general information on running applications and the Environment Abstraction
Layer (EAL) options.
Sample ipv4_rules_file.txt
--------------------------
.. code-block:: console
#file format:
#src_ip/masklen dst_ip/masklen src_port : mask dst_port : mask proto/mask priority
#
2.2.2.3/24 2.2.2.7/24 32 : 0xffff 33 : 0xffff 17/0xff 0
9.9.9.3/24 9.9.9.7/24 32 : 0xffff 33 : 0xffff 17/0xff 1
9.9.9.3/24 9.9.9.7/24 32 : 0xffff 33 : 0xffff 6/0xff 2
9.9.8.3/24 9.9.8.7/24 32 : 0xffff 33 : 0xffff 6/0xff 3
6.7.8.9/24 2.3.4.5/24 32 : 0x0000 33 : 0x0000 132/0xff 4
Explanation
-----------
The following sections provide an explanation of the main components of the
code.
All DPDK library functions used in the sample code are prefixed with ``rte_``
and are explained in detail in the *DPDK API Documentation*.
ACL field definitions for the IPv4 5 tuple rule
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The following field definitions are used when creating the ACL table during
initialisation of the ``Flow Classify`` application..
.. code-block:: c
enum {
PROTO_FIELD_IPV4,
SRC_FIELD_IPV4,
DST_FIELD_IPV4,
SRCP_FIELD_IPV4,
DSTP_FIELD_IPV4,
NUM_FIELDS_IPV4
};
enum {
PROTO_INPUT_IPV4,
SRC_INPUT_IPV4,
DST_INPUT_IPV4,
SRCP_DESTP_INPUT_IPV4
};
static struct rte_acl_field_def ipv4_defs[NUM_FIELDS_IPV4] = {
/* first input field - always one byte long. */
{
.type = RTE_ACL_FIELD_TYPE_BITMASK,
.size = sizeof(uint8_t),
.field_index = PROTO_FIELD_IPV4,
.input_index = PROTO_INPUT_IPV4,
.offset = sizeof(struct rte_ether_hdr) +
offsetof(struct rte_ipv4_hdr, next_proto_id),
},
/* next input field (IPv4 source address) - 4 consecutive bytes. */
{
/* rte_flow uses a bit mask for IPv4 addresses */
.type = RTE_ACL_FIELD_TYPE_BITMASK,
.size = sizeof(uint32_t),
.field_index = SRC_FIELD_IPV4,
.input_index = SRC_INPUT_IPV4,
.offset = sizeof(struct rte_ether_hdr) +
offsetof(struct rte_ipv4_hdr, src_addr),
},
/* next input field (IPv4 destination address) - 4 consecutive bytes. */
{
/* rte_flow uses a bit mask for IPv4 addresses */
.type = RTE_ACL_FIELD_TYPE_BITMASK,
.size = sizeof(uint32_t),
.field_index = DST_FIELD_IPV4,
.input_index = DST_INPUT_IPV4,
.offset = sizeof(struct rte_ether_hdr) +
offsetof(struct rte_ipv4_hdr, dst_addr),
},
/*
* Next 2 fields (src & dst ports) form 4 consecutive bytes.
* They share the same input index.
*/
{
/* rte_flow uses a bit mask for protocol ports */
.type = RTE_ACL_FIELD_TYPE_BITMASK,
.size = sizeof(uint16_t),
.field_index = SRCP_FIELD_IPV4,
.input_index = SRCP_DESTP_INPUT_IPV4,
.offset = sizeof(struct rte_ether_hdr) +
sizeof(struct rte_ipv4_hdr) +
offsetof(struct rte_tcp_hdr, src_port),
},
{
/* rte_flow uses a bit mask for protocol ports */
.type = RTE_ACL_FIELD_TYPE_BITMASK,
.size = sizeof(uint16_t),
.field_index = DSTP_FIELD_IPV4,
.input_index = SRCP_DESTP_INPUT_IPV4,
.offset = sizeof(struct rte_ether_hdr) +
sizeof(struct rte_ipv4_hdr) +
offsetof(struct rte_tcp_hdr, dst_port),
},
};
The Main Function
~~~~~~~~~~~~~~~~~
The ``main()`` function performs the initialization and calls the execution
threads for each lcore.
The first task is to initialize the Environment Abstraction Layer (EAL).
The ``argc`` and ``argv`` arguments are provided to the ``rte_eal_init()``
function. The value returned is the number of parsed arguments:
.. code-block:: c
int ret = rte_eal_init(argc, argv);
if (ret < 0)
rte_exit(EXIT_FAILURE, "Error with EAL initialization\n");
It then parses the flow_classify application arguments
.. code-block:: c
ret = parse_args(argc, argv);
if (ret < 0)
rte_exit(EXIT_FAILURE, "Invalid flow_classify parameters\n");
The ``main()`` function also allocates a mempool to hold the mbufs
(Message Buffers) used by the application:
.. code-block:: c
mbuf_pool = rte_mempool_create("MBUF_POOL",
NUM_MBUFS * nb_ports,
MBUF_SIZE,
MBUF_CACHE_SIZE,
sizeof(struct rte_pktmbuf_pool_private),
rte_pktmbuf_pool_init, NULL,
rte_pktmbuf_init, NULL,
rte_socket_id(),
0);
mbufs are the packet buffer structure used by DPDK. They are explained in
detail in the "Mbuf Library" section of the *DPDK Programmer's Guide*.
The ``main()`` function also initializes all the ports using the user defined
``port_init()`` function which is explained in the next section:
.. code-block:: c
RTE_ETH_FOREACH_DEV(portid) {
if (port_init(portid, mbuf_pool) != 0) {
rte_exit(EXIT_FAILURE,
"Cannot init port %" PRIu8 "\n", portid);
}
}
The ``main()`` function creates the ``flow classifier object`` and adds an ``ACL
table`` to the flow classifier.
.. code-block:: c
struct flow_classifier {
struct rte_flow_classifier *cls;
};
struct flow_classifier_acl {
struct flow_classifier cls;
} __rte_cache_aligned;
/* Memory allocation */
size = RTE_CACHE_LINE_ROUNDUP(sizeof(struct flow_classifier_acl));
cls_app = rte_zmalloc(NULL, size, RTE_CACHE_LINE_SIZE);
if (cls_app == NULL)
rte_exit(EXIT_FAILURE, "Cannot allocate classifier memory\n");
cls_params.name = "flow_classifier";
cls_params.socket_id = socket_id;
cls_app->cls = rte_flow_classifier_create(&cls_params);
if (cls_app->cls == NULL) {
rte_free(cls_app);
rte_exit(EXIT_FAILURE, "Cannot create classifier\n");
}
/* initialise ACL table params */
table_acl_params.name = "table_acl_ipv4_5tuple";
table_acl_params.n_rule_fields = RTE_DIM(ipv4_defs);
table_acl_params.n_rules = FLOW_CLASSIFY_MAX_RULE_NUM;
memcpy(table_acl_params.field_format, ipv4_defs, sizeof(ipv4_defs));
/* initialise table create params */
cls_table_params.ops = &rte_table_acl_ops,
cls_table_params.arg_create = &table_acl_params,
cls_table_params.type = RTE_FLOW_CLASSIFY_TABLE_ACL_IP4_5TUPLE;
ret = rte_flow_classify_table_create(cls_app->cls, &cls_table_params);
if (ret) {
rte_flow_classifier_free(cls_app->cls);
rte_free(cls);
rte_exit(EXIT_FAILURE, "Failed to create classifier table\n");
}
It then reads the ipv4_rules_file.txt file and initialises the parameters for
the ``rte_flow_classify_table_entry_add`` API.
This API adds a rule to the ACL table.
.. code-block:: c
if (add_rules(parm_config.rule_ipv4_name)) {
rte_flow_classifier_free(cls_app->cls);
rte_free(cls_app);
rte_exit(EXIT_FAILURE, "Failed to add rules\n");
}
Once the initialization is complete, the application is ready to launch a
function on an lcore. In this example ``lcore_main()`` is called on a single
lcore.
.. code-block:: c
lcore_main(cls_app);
The ``lcore_main()`` function is explained below.
The Port Initialization Function
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The main functional part of the port initialization used in the Basic
Forwarding application is shown below:
.. code-block:: c
static inline int
port_init(uint16_t port, struct rte_mempool *mbuf_pool)
{
struct rte_eth_conf port_conf = port_conf_default;
const uint16_t rx_rings = 1, tx_rings = 1;
struct rte_ether_addr addr;
int retval;
uint16_t q;
/* Configure the Ethernet device. */
retval = rte_eth_dev_configure(port, rx_rings, tx_rings, &port_conf);
if (retval != 0)
return retval;
/* Allocate and set up 1 RX queue per Ethernet port. */
for (q = 0; q < rx_rings; q++) {
retval = rte_eth_rx_queue_setup(port, q, RX_RING_SIZE,
rte_eth_dev_socket_id(port), NULL, mbuf_pool);
if (retval < 0)
return retval;
}
/* Allocate and set up 1 TX queue per Ethernet port. */
for (q = 0; q < tx_rings; q++) {
retval = rte_eth_tx_queue_setup(port, q, TX_RING_SIZE,
rte_eth_dev_socket_id(port), NULL);
if (retval < 0)
return retval;
}
/* Start the Ethernet port. */
retval = rte_eth_dev_start(port);
if (retval < 0)
return retval;
/* Display the port MAC address. */
retval = rte_eth_macaddr_get(port, &addr);
if (retval < 0)
return retval;
printf("Port %u MAC: %02" PRIx8 " %02" PRIx8 " %02" PRIx8
" %02" PRIx8 " %02" PRIx8 " %02" PRIx8 "\n",
port,
addr.addr_bytes[0], addr.addr_bytes[1],
addr.addr_bytes[2], addr.addr_bytes[3],
addr.addr_bytes[4], addr.addr_bytes[5]);
/* Enable RX in promiscuous mode for the Ethernet device. */
retval = rte_eth_promiscuous_enable(port);
if (retval != 0)
return retval;
return 0;
}
The Ethernet ports are configured with default settings using the
``rte_eth_dev_configure()`` function and the ``port_conf_default`` struct.
.. code-block:: c
static const struct rte_eth_conf port_conf_default = {
.rxmode = { .max_rx_pkt_len = RTE_ETHER_MAX_LEN }
};
For this example the ports are set up with 1 RX and 1 TX queue using the
``rte_eth_rx_queue_setup()`` and ``rte_eth_tx_queue_setup()`` functions.
The Ethernet port is then started:
.. code-block:: c
retval = rte_eth_dev_start(port);
Finally the RX port is set in promiscuous mode:
.. code-block:: c
retval = rte_eth_promiscuous_enable(port);
The Add Rules function
~~~~~~~~~~~~~~~~~~~~~~
The ``add_rules`` function reads the ``ipv4_rules_file.txt`` file and calls the
``add_classify_rule`` function which calls the
``rte_flow_classify_table_entry_add`` API.
.. code-block:: c
static int
add_rules(const char *rule_path)
{
FILE *fh;
char buff[LINE_MAX];
unsigned int i = 0;
unsigned int total_num = 0;
struct rte_eth_ntuple_filter ntuple_filter;
fh = fopen(rule_path, "rb");
if (fh == NULL)
rte_exit(EXIT_FAILURE, "%s: Open %s failed\n", __func__,
rule_path);
fseek(fh, 0, SEEK_SET);
i = 0;
while (fgets(buff, LINE_MAX, fh) != NULL) {
i++;
if (is_bypass_line(buff))
continue;
if (total_num >= FLOW_CLASSIFY_MAX_RULE_NUM - 1) {
printf("\nINFO: classify rule capacity %d reached\n",
total_num);
break;
}
if (parse_ipv4_5tuple_rule(buff, &ntuple_filter) != 0)
rte_exit(EXIT_FAILURE,
"%s Line %u: parse rules error\n",
rule_path, i);
if (add_classify_rule(&ntuple_filter) != 0)
rte_exit(EXIT_FAILURE, "add rule error\n");
total_num++;
}
fclose(fh);
return 0;
}
The Lcore Main function
~~~~~~~~~~~~~~~~~~~~~~~
As we saw above the ``main()`` function calls an application function on the
available lcores.
The ``lcore_main`` function calls the ``rte_flow_classifier_query`` API.
For the Basic Forwarding application the ``lcore_main`` function looks like the
following:
.. code-block:: c
/* flow classify data */
static int num_classify_rules;
static struct rte_flow_classify_rule *rules[MAX_NUM_CLASSIFY];
static struct rte_flow_classify_ipv4_5tuple_stats ntuple_stats;
static struct rte_flow_classify_stats classify_stats = {
.stats = (void *)&ntuple_stats
};
static __rte_noreturn void
lcore_main(cls_app)
{
uint16_t port;
/*
* Check that the port is on the same NUMA node as the polling thread
* for best performance.
*/
RTE_ETH_FOREACH_DEV(port)
if (rte_eth_dev_socket_id(port) > 0 &&
rte_eth_dev_socket_id(port) != (int)rte_socket_id()) {
printf("\n\n");
printf("WARNING: port %u is on remote NUMA node\n",
port);
printf("to polling thread.\n");
printf("Performance will not be optimal.\n");
printf("\nCore %u forwarding packets. \n",
rte_lcore_id());
printf("[Ctrl+C to quit]\n
}
/* Run until the application is quit or killed. */
for (;;) {
/*
* Receive packets on a port and forward them on the paired
* port. The mapping is 0 -> 1, 1 -> 0, 2 -> 3, 3 -> 2, etc.
*/
RTE_ETH_FOREACH_DEV(port) {
/* Get burst of RX packets, from first port of pair. */
struct rte_mbuf *bufs[BURST_SIZE];
const uint16_t nb_rx = rte_eth_rx_burst(port, 0,
bufs, BURST_SIZE);
if (unlikely(nb_rx == 0))
continue;
for (i = 0; i < MAX_NUM_CLASSIFY; i++) {
if (rules[i]) {
ret = rte_flow_classifier_query(
cls_app->cls,
bufs, nb_rx, rules[i],
&classify_stats);
if (ret)
printf(
"rule [%d] query failed ret [%d]\n\n",
i, ret);
else {
printf(
"rule[%d] count=%"PRIu64"\n",
i, ntuple_stats.counter1);
printf("proto = %d\n",
ntuple_stats.ipv4_5tuple.proto);
}
}
}
/* Send burst of TX packets, to second port of pair. */
const uint16_t nb_tx = rte_eth_tx_burst(port ^ 1, 0,
bufs, nb_rx);
/* Free any unsent packets. */
if (unlikely(nb_tx < nb_rx)) {
uint16_t buf;
for (buf = nb_tx; buf < nb_rx; buf++)
rte_pktmbuf_free(bufs[buf]);
}
}
}
}
The main work of the application is done within the loop:
.. code-block:: c
for (;;) {
RTE_ETH_FOREACH_DEV(port) {
/* Get burst of RX packets, from first port of pair. */
struct rte_mbuf *bufs[BURST_SIZE];
const uint16_t nb_rx = rte_eth_rx_burst(port, 0,
bufs, BURST_SIZE);
if (unlikely(nb_rx == 0))
continue;
/* Send burst of TX packets, to second port of pair. */
const uint16_t nb_tx = rte_eth_tx_burst(port ^ 1, 0,
bufs, nb_rx);
/* Free any unsent packets. */
if (unlikely(nb_tx < nb_rx)) {
uint16_t buf;
for (buf = nb_tx; buf < nb_rx; buf++)
rte_pktmbuf_free(bufs[buf]);
}
}
}
Packets are received in bursts on the RX ports and transmitted in bursts on
the TX ports. The ports are grouped in pairs with a simple mapping scheme
using the an XOR on the port number::
0 -> 1
1 -> 0
2 -> 3
3 -> 2
etc.
The ``rte_eth_tx_burst()`` function frees the memory buffers of packets that
are transmitted. If packets fail to transmit, ``(nb_tx < nb_rx)``, then they
must be freed explicitly using ``rte_pktmbuf_free()``.
The forwarding loop can be interrupted and the application closed using
``Ctrl-C``.
Reference in New Issue View Git Blame Copy Permalink