[dpdk-dev] [PATCH v2] app/testpmd: make txonly mode generate multiple flows

[Yongseok Koh]

Testpmd can generate multiple flows without taking much cost and this could
be a simple traffic generator for developer's quick tests. IP destination
address is varied.

Signed-off-by: Yongseok Koh <ys...@mellanox.com>
---

v2:
* Add detailed explanation in a comment.

 app/test-pmd/txonly.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/app/test-pmd/txonly.c b/app/test-pmd/txonly.c
index 1f08b6ed3..253cf2385 100644
--- a/app/test-pmd/txonly.c
+++ b/app/test-pmd/txonly.c
@@ -44,7 +44,7 @@
 #define UDP_DST_PORT 1024
 
 #define IP_SRC_ADDR ((192U << 24) | (168 << 16) | (0 << 8) | 1)
-#define IP_DST_ADDR ((192U << 24) | (168 << 16) | (0 << 8) | 2)
+#define IP_DST_ADDR ((192U << 24) | (168 << 16))
 
 #define IP_DEFTTL  64   /* from RFC 1340. */
 #define IP_VERSION 0x40
@@ -52,6 +52,7 @@
 #define IP_VHL_DEF (IP_VERSION | IP_HDRLEN)
 
 static struct ipv4_hdr  pkt_ip_hdr;  /**< IP header of transmitted packets. */
+static __thread uint8_t ip_var; /**< IP address variation */
 static struct udp_hdr pkt_udp_hdr; /**< UDP header of transmitted packets. */
 
 static void
@@ -159,6 +160,7 @@ pkt_burst_transmit(struct fwd_stream *fs)
        struct rte_mbuf *pkt_seg;
        struct rte_mempool *mbp;
        struct ether_hdr eth_hdr;
+       struct ipv4_hdr *ip_hdr;
        uint16_t nb_tx;
        uint16_t nb_pkt;
        uint16_t vlan_tci, vlan_tci_outer;
@@ -237,6 +239,17 @@ pkt_burst_transmit(struct fwd_stream *fs)
                copy_buf_to_pkt(&eth_hdr, sizeof(eth_hdr), pkt, 0);
                copy_buf_to_pkt(&pkt_ip_hdr, sizeof(pkt_ip_hdr), pkt,
                                sizeof(struct ether_hdr));
+               ip_hdr = rte_pktmbuf_mtod_offset(pkt, struct ipv4_hdr *,
+                                                sizeof(struct ether_hdr));
+               /*
+                * Generate multiple flows by varying IP dest addr. This enables
+                * packets are well distributed by RSS in receiver side if any
+                * and txonly mode can be a decent packet generator for
+                * developer's quick performance regression test.
+                */
+               ip_hdr->dst_addr =
+                       rte_cpu_to_be_32(IP_DST_ADDR | (ip_var++ << 8) |
+                                        (rte_lcore_id() + 1));
                copy_buf_to_pkt(&pkt_udp_hdr, sizeof(pkt_udp_hdr), pkt,
                                sizeof(struct ether_hdr) +
                                sizeof(struct ipv4_hdr));
-- 
2.11.0