app/testpmd: fix txonly flow generation entropy

The testpmd application in txonly forwarding mode has an option
to generate the packet flows by varying the destination IP address.
The patch increments the IP for each packet sent, this improves
the entropy and RSS distribution on the peer receiving size
is getting more uniform.

Fixes: 01b645dcff7f ("app/testpmd: move txonly prepare in separate function")
Cc: stable@dpdk.org
Signed-off-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>

diff --git a/app/test-pmd/txonly.c b/app/test-pmd/txonly.c
index 4b5bec4..8a1989f 100644 (file)
--- a/app/test-pmd/txonly.c
+++ b/app/test-pmd/txonly.c
@@ -153,7 +153,6 @@ pkt_burst_prepare(struct rte_mbuf *pkt, struct rte_mempool *mbp,
                const uint16_t vlan_tci_outer, const uint64_t ol_flags)
 {
        struct rte_mbuf *pkt_segs[RTE_MAX_SEGS_PER_PKT];
-       uint8_t  ip_var = RTE_PER_LCORE(_ip_var);
        struct rte_mbuf *pkt_seg;
        uint32_t nb_segs, pkt_len;
        uint8_t i;
@@ -193,6 +192,7 @@ pkt_burst_prepare(struct rte_mbuf *pkt, struct rte_mempool *mbp,
        copy_buf_to_pkt(&pkt_ip_hdr, sizeof(pkt_ip_hdr), pkt,
                        sizeof(struct rte_ether_hdr));
        if (txonly_multi_flow) {
+               uint8_t  ip_var = RTE_PER_LCORE(_ip_var);
                struct rte_ipv4_hdr *ip_hdr;
                uint32_t addr;
 
@@ -208,6 +208,7 @@ pkt_burst_prepare(struct rte_mbuf *pkt, struct rte_mempool *mbp,
                 */
                addr = (tx_ip_dst_addr | (ip_var++ << 8)) + rte_lcore_id();
                ip_hdr->src_addr = rte_cpu_to_be_32(addr);
+               RTE_PER_LCORE(_ip_var) = ip_var;
        }
        copy_buf_to_pkt(&pkt_udp_hdr, sizeof(pkt_udp_hdr), pkt,
                        sizeof(struct rte_ether_hdr) +
@@ -315,7 +316,7 @@ pkt_burst_transmit(struct fwd_stream *fs)
        fs->tx_packets += nb_tx;
 
        if (txonly_multi_flow)
-               RTE_PER_LCORE(_ip_var) += nb_tx;
+               RTE_PER_LCORE(_ip_var) -= nb_pkt - nb_tx;
 
 #ifdef RTE_TEST_PMD_RECORD_BURST_STATS
        fs->tx_burst_stats.pkt_burst_spread[nb_tx]++;