[dpdk-dev] [PATCH v4] examples/l2fwd: add cmdline option for forwarding port info

[<pbhagavatula@marvell.com>]

From: Vamsi Attunuru <vattunuru@marvell.com>

Current l2fwd application statically configures adjacent ports as
destination ports for forwarding the traffic.

Add a portmap option to pass the forwarding port pair mapping which allows
the user to configure forwarding port mapping.

If no portmap argument is specified, destination port map is not
changed and traffic gets forwarded with existing mapping.

To align port/queue configuration of each lcore with destination port
map, port/queue configuration of each lcore gets modified when portmap
option is specified.

Ex: ./l2fwd -c 0xff -- -p 0x3f -q 2 --portmap="(0,3)(1,4)(2,5)"

With above portmap option, traffic received from portid = 0 gets forwarded
to port = 3 and vice versa, similarly traffic gets forwarded on other port
pairs (1,4) and (2,5)

Signed-off-by: Vamsi Attunuru <vattunuru@marvell.com>
Signed-off-by: Pavan Nikhilesh <pbhagavatula@marvell.com>
Acked-by: Andrzej Ostruszka <aostruszka@marvell.com>
---
 v4 Changes:
 * Documentation changes. (Sunil)
 * reduce port_pair_params_array size. (Sunil)

 v3 Changes:
 * s/config/portmap/
 * rebase on master

 v2 Changes:
 * Fix command option format in docs.
 * Use memcpy instead of snprintf.
 * Rephrase if-else condition.

 doc/guides/rel_notes/release_20_05.rst        |   7 +
 .../sample_app_ug/l2_forward_real_virtual.rst |  17 +-
 examples/l2fwd/main.c                         | 182 +++++++++++++++---
 3 files changed, 180 insertions(+), 26 deletions(-)

diff --git a/doc/guides/rel_notes/release_20_05.rst b/doc/guides/rel_notes/release_20_05.rst
index b124c3f28..019bec5d7 100644
--- a/doc/guides/rel_notes/release_20_05.rst
+++ b/doc/guides/rel_notes/release_20_05.rst
@@ -212,6 +212,13 @@ New Features
   * Added IPsec inbound load-distribution support for ipsec-secgw application
     using NIC load distribution feature(Flow Director).

+* **Added --portmap command line parameter to l2fwd example.**
+
+  Added new command line option ``--portmap="(port, port)[,(port, port)]"`` to
+  pass forwarding port details.
+  See the :doc:`doc/guides/sample_app_ug/l2_forward_real_virtual` for more
+  details of this parameter usage.
+

 Removed Items
 -------------
diff --git a/doc/guides/sample_app_ug/l2_forward_real_virtual.rst b/doc/guides/sample_app_ug/l2_forward_real_virtual.rst
index 39d6b0067..90ca609d6 100644
--- a/doc/guides/sample_app_ug/l2_forward_real_virtual.rst
+++ b/doc/guides/sample_app_ug/l2_forward_real_virtual.rst
@@ -91,7 +91,10 @@ The application requires a number of command line options:

 .. code-block:: console

-    ./build/l2fwd [EAL options] -- -p PORTMASK [-q NQ] --[no-]mac-updating
+    ./build/l2fwd [EAL options] -- -p PORTMASK
+                                   [-q NQ]
+                                   --[no-]mac-updating
+                                   [--portmap="(port, port)[,(port, port)]"]

 where,

@@ -99,7 +102,9 @@ where,

 *   q NQ: A number of queues (=ports) per lcore (default is 1)

-*   --[no-]mac-updating: Enable or disable MAC addresses updating (enabled by default).
+*   --[no-]mac-updating: Enable or disable MAC addresses updating (enabled by default)
+
+*   --portmap="(port,port)[,(port,port)]": Determines forwarding ports mapping.

 To run the application in linux environment with 4 lcores, 16 ports and 8 RX queues per lcore and MAC address
 updating enabled, issue the command:
@@ -108,6 +113,14 @@ updating enabled, issue the command:

     $ ./build/l2fwd -l 0-3 -n 4 -- -q 8 -p ffff

+To run the application in linux environment with 4 lcores, 4 ports, 8 RX queues
+per lcore, to forward RX traffic of ports 0 & 1 on ports 2 & 3 respectively and
+vice versa, issue the command:
+
+.. code-block:: console
+
+    $ ./build/l2fwd -l 0-3 -n 4 -- -q 8 -p f --portmap="(0,2)(1,3)"
+
 Refer to the *DPDK Getting Started Guide* for general information on running applications
 and the Environment Abstraction Layer (EAL) options.

diff --git a/examples/l2fwd/main.c b/examples/l2fwd/main.c
index 88ddfe589..1d84cd789 100644
--- a/examples/l2fwd/main.c
+++ b/examples/l2fwd/main.c
@@ -38,6 +38,7 @@
 #include <rte_ethdev.h>
 #include <rte_mempool.h>
 #include <rte_mbuf.h>
+#include <rte_string_fns.h>

 static volatile bool force_quit;

@@ -67,6 +68,15 @@ static uint32_t l2fwd_enabled_port_mask = 0;
 /* list of enabled ports */
 static uint32_t l2fwd_dst_ports[RTE_MAX_ETHPORTS];

+struct port_pair_params {
+#define NUM_PORTS	2
+	uint16_t port[NUM_PORTS];
+} __rte_cache_aligned;
+
+static struct port_pair_params port_pair_params_array[RTE_MAX_ETHPORTS / 2];
+static struct port_pair_params *port_pair_params;
+static uint16_t nb_port_pair_params;
+
 static unsigned int l2fwd_rx_queue_per_lcore = 1;

 #define MAX_RX_QUEUE_PER_LCORE 16
@@ -294,11 +304,13 @@ l2fwd_usage(const char *prgname)
 	printf("%s [EAL options] -- -p PORTMASK [-q NQ]\n"
 	       "  -p PORTMASK: hexadecimal bitmask of ports to configure\n"
 	       "  -q NQ: number of queue (=ports) per lcore (default is 1)\n"
-		   "  -T PERIOD: statistics will be refreshed each PERIOD seconds (0 to disable, 10 default, 86400 maximum)\n"
-		   "  --[no-]mac-updating: Enable or disable MAC addresses updating (enabled by default)\n"
-		   "      When enabled:\n"
-		   "       - The source MAC address is replaced by the TX port MAC address\n"
-		   "       - The destination MAC address is replaced by 02:00:00:00:00:TX_PORT_ID\n",
+	       "  -T PERIOD: statistics will be refreshed each PERIOD seconds (0 to disable, 10 default, 86400 maximum)\n"
+	       "  --[no-]mac-updating: Enable or disable MAC addresses updating (enabled by default)\n"
+	       "      When enabled:\n"
+	       "       - The source MAC address is replaced by the TX port MAC address\n"
+	       "       - The destination MAC address is replaced by 02:00:00:00:00:TX_PORT_ID\n"
+	       "  --portmap: Configure forwarding port pair mapping\n"
+	       "	      Default: alternate port pairs\n\n",
 	       prgname);
 }

@@ -319,6 +331,61 @@ l2fwd_parse_portmask(const char *portmask)
 	return pm;
 }

+static int
+l2fwd_parse_port_pair_config(const char *q_arg)
+{
+	enum fieldnames {
+		FLD_PORT1 = 0,
+		FLD_PORT2,
+		_NUM_FLD
+	};
+	unsigned long int_fld[_NUM_FLD];
+	const char *p, *p0 = q_arg;
+	char *str_fld[_NUM_FLD];
+	unsigned int size;
+	char s[256];
+	char *end;
+	int i;
+
+	nb_port_pair_params = 0;
+
+	while ((p = strchr(p0, '(')) != NULL) {
+		++p;
+		p0 = strchr(p, ')');
+		if (p0 == NULL)
+			return -1;
+
+		size = p0 - p;
+		if (size >= sizeof(s))
+			return -1;
+
+		memcpy(s, p, size);
+		s[size] = '\0';
+		if (rte_strsplit(s, sizeof(s), str_fld,
+				 _NUM_FLD, ',') != _NUM_FLD)
+			return -1;
+		for (i = 0; i < _NUM_FLD; i++) {
+			errno = 0;
+			int_fld[i] = strtoul(str_fld[i], &end, 0);
+			if (errno != 0 || end == str_fld[i] ||
+			    int_fld[i] >= RTE_MAX_ETHPORTS)
+				return -1;
+		}
+		if (nb_port_pair_params >= RTE_MAX_ETHPORTS/2) {
+			printf("exceeded max number of port pair params: %hu\n",
+				nb_port_pair_params);
+			return -1;
+		}
+		port_pair_params_array[nb_port_pair_params].port[0] =
+				(uint16_t)int_fld[FLD_PORT1];
+		port_pair_params_array[nb_port_pair_params].port[1] =
+				(uint16_t)int_fld[FLD_PORT2];
+		++nb_port_pair_params;
+	}
+	port_pair_params = port_pair_params_array;
+	return 0;
+}
+
 static unsigned int
 l2fwd_parse_nqueue(const char *q_arg)
 {
@@ -361,6 +428,7 @@ static const char short_options[] =

 #define CMD_LINE_OPT_MAC_UPDATING "mac-updating"
 #define CMD_LINE_OPT_NO_MAC_UPDATING "no-mac-updating"
+#define CMD_LINE_OPT_PORTMAP_CONFIG "portmap"

 enum {
 	/* long options mapped to a short option */
@@ -368,11 +436,13 @@ enum {
 	/* first long only option value must be >= 256, so that we won't
 	 * conflict with short options */
 	CMD_LINE_OPT_MIN_NUM = 256,
+	CMD_LINE_OPT_PORTMAP_NUM,
 };

 static const struct option lgopts[] = {
 	{ CMD_LINE_OPT_MAC_UPDATING, no_argument, &mac_updating, 1},
 	{ CMD_LINE_OPT_NO_MAC_UPDATING, no_argument, &mac_updating, 0},
+	{ CMD_LINE_OPT_PORTMAP_CONFIG, 1, 0, CMD_LINE_OPT_PORTMAP_NUM},
 	{NULL, 0, 0, 0}
 };

@@ -386,6 +456,7 @@ l2fwd_parse_args(int argc, char **argv)
 	char *prgname = argv[0];

 	argvopt = argv;
+	port_pair_params = NULL;

 	while ((opt = getopt_long(argc, argvopt, short_options,
 				  lgopts, &option_index)) != EOF) {
@@ -423,7 +494,13 @@ l2fwd_parse_args(int argc, char **argv)
 			break;

 		/* long options */
-		case 0:
+		case CMD_LINE_OPT_PORTMAP_NUM:
+			ret = l2fwd_parse_port_pair_config(optarg);
+			if (ret) {
+				fprintf(stderr, "Invalid config\n");
+				l2fwd_usage(prgname);
+				return -1;
+			}
 			break;

 		default:
@@ -440,6 +517,48 @@ l2fwd_parse_args(int argc, char **argv)
 	return ret;
 }

+/*
+ * Check port pair config with enabled port mask,
+ * and for valid port pair combinations.
+ */
+static int
+check_port_pair_config(void)
+{
+	uint32_t port_pair_config_mask = 0;
+	uint32_t port_pair_mask = 0;
+	uint16_t index, i, portid;
+
+	for (index = 0; index < nb_port_pair_params; index++) {
+		port_pair_mask = 0;
+
+		for (i = 0; i < NUM_PORTS; i++)  {
+			portid = port_pair_params[index].port[i];
+			if ((l2fwd_enabled_port_mask & (1 << portid)) == 0) {
+				printf("port %u is not enabled in port mask\n",
+				       portid);
+				return -1;
+			}
+			if (!rte_eth_dev_is_valid_port(portid)) {
+				printf("port %u is not present on the board\n",
+				       portid);
+				return -1;
+			}
+
+			port_pair_mask |= 1 << portid;
+		}
+
+		if (port_pair_config_mask & port_pair_mask) {
+			printf("port %u is used in other port pairs\n", portid);
+			return -1;
+		}
+		port_pair_config_mask |= port_pair_mask;
+	}
+
+	l2fwd_enabled_port_mask &= port_pair_config_mask;
+
+	return 0;
+}
+
 /* Check the link status of all ports in up to 9s, and print them finally */
 static void
 check_all_ports_link_status(uint32_t port_mask)
@@ -555,6 +674,11 @@ main(int argc, char **argv)
 	if (nb_ports == 0)
 		rte_exit(EXIT_FAILURE, "No Ethernet ports - bye\n");

+	if (port_pair_params != NULL) {
+		if (check_port_pair_config() < 0)
+			rte_exit(EXIT_FAILURE, "Invalid port pair config\n");
+	}
+
 	/* check port mask to possible port mask */
 	if (l2fwd_enabled_port_mask & ~((1 << nb_ports) - 1))
 		rte_exit(EXIT_FAILURE, "Invalid portmask; possible (0x%x)\n",
@@ -565,26 +689,35 @@ main(int argc, char **argv)
 		l2fwd_dst_ports[portid] = 0;
 	last_port = 0;

-	/*
-	 * Each logical core is assigned a dedicated TX queue on each port.
-	 */
-	RTE_ETH_FOREACH_DEV(portid) {
-		/* skip ports that are not enabled */
-		if ((l2fwd_enabled_port_mask & (1 << portid)) == 0)
-			continue;
+	/* populate destination port details */
+	if (port_pair_params != NULL) {
+		uint16_t idx, p;

-		if (nb_ports_in_mask % 2) {
-			l2fwd_dst_ports[portid] = last_port;
-			l2fwd_dst_ports[last_port] = portid;
+		for (idx = 0; idx < (nb_port_pair_params << 1); idx++) {
+			p = idx & 1;
+			portid = port_pair_params[idx >> 1].port[p];
+			l2fwd_dst_ports[portid] =
+				port_pair_params[idx >> 1].port[p ^ 1];
 		}
-		else
-			last_port = portid;
+	} else {
+		RTE_ETH_FOREACH_DEV(portid) {
+			/* skip ports that are not enabled */
+			if ((l2fwd_enabled_port_mask & (1 << portid)) == 0)
+				continue;

-		nb_ports_in_mask++;
-	}
-	if (nb_ports_in_mask % 2) {
-		printf("Notice: odd number of ports in portmask.\n");
-		l2fwd_dst_ports[last_port] = last_port;
+			if (nb_ports_in_mask % 2) {
+				l2fwd_dst_ports[portid] = last_port;
+				l2fwd_dst_ports[last_port] = portid;
+			} else {
+				last_port = portid;
+			}
+
+			nb_ports_in_mask++;
+		}
+		if (nb_ports_in_mask % 2) {
+			printf("Notice: odd number of ports in portmask.\n");
+			l2fwd_dst_ports[last_port] = last_port;
+		}
 	}

 	rx_lcore_id = 0;
@@ -613,7 +746,8 @@ main(int argc, char **argv)

 		qconf->rx_port_list[qconf->n_rx_port] = portid;
 		qconf->n_rx_port++;
-		printf("Lcore %u: RX port %u\n", rx_lcore_id, portid);
+		printf("Lcore %u: RX port %u TX port %u\n", rx_lcore_id,
+		       portid, l2fwd_dst_ports[portid]);
 	}

 	nb_mbufs = RTE_MAX(nb_ports * (nb_rxd + nb_txd + MAX_PKT_BURST +
--
2.17.1