Google cloud routes traffic using IP addresses without the support of MAC
addresses, so changing source IP address for txonly-multi-flow can have
negative performance implications for net/gve when using testpmd. This
patch updates txonly multiflow mode to modify source ports instead of
source IP addresses.
The change can be tested with the following command:
dpdk-testpmd -- --forward-mode=txonly --txonly-multi-flow \
--txip=<SRC>,<DST>
Signed-off-by: Joshua Washington <joshw...@google.com>
Reviewed-by: Rushil Gupta <rush...@google.com>
---
app/test-pmd/txonly.c | 34 ++++++++++++++++++----------------
1 file changed, 18 insertions(+), 16 deletions(-)
diff --git a/app/test-pmd/txonly.c b/app/test-pmd/txonly.c
index b3d6873104..7fc743b508 100644
--- a/app/test-pmd/txonly.c
+++ b/app/test-pmd/txonly.c
@@ -56,7 +56,7 @@ uint32_t tx_ip_dst_addr = (198U << 24) | (18 << 16) | (0 <<
8) | 2;
#define IP_DEFTTL 64 /* from RFC 1340. */
static struct rte_ipv4_hdr pkt_ip_hdr; /**< IP header of transmitted packets.
*/
-RTE_DEFINE_PER_LCORE(uint8_t, _ip_var); /**< IP address variation */
+RTE_DEFINE_PER_LCORE(uint16_t, _src_var); /**< Source port variation */
static struct rte_udp_hdr pkt_udp_hdr; /**< UDP header of tx packets. */
static uint64_t timestamp_mask; /**< Timestamp dynamic flag mask */
@@ -230,28 +230,30 @@ pkt_burst_prepare(struct rte_mbuf *pkt, struct
rte_mempool *mbp,
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 rte_ether_hdr));
+ copy_buf_to_pkt(&pkt_udp_hdr, sizeof(pkt_udp_hdr), pkt,
+ sizeof(struct rte_ether_hdr) +
+ sizeof(struct rte_ipv4_hdr));
if (txonly_multi_flow) {
- uint8_t ip_var = RTE_PER_LCORE(_ip_var);
- struct rte_ipv4_hdr *ip_hdr;
- uint32_t addr;
+ uint16_t src_var = RTE_PER_LCORE(_src_var);
+ struct rte_udp_hdr *udp_hdr;
+ uint16_t port;
- ip_hdr = rte_pktmbuf_mtod_offset(pkt,
- struct rte_ipv4_hdr *,
- sizeof(struct rte_ether_hdr));
+ udp_hdr = rte_pktmbuf_mtod_offset(pkt,
+ struct rte_udp_hdr *,
+ sizeof(struct rte_ether_hdr) +
+ sizeof(struct rte_ipv4_hdr));
/*
- * Generate multiple flows by varying IP src addr. This
- * enables packets are well distributed by RSS in
+ * Generate multiple flows by varying UDP source port.
+ * 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.
*/
- 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;
+
+ port = src_var++;
+ udp_hdr->src_port = rte_cpu_to_be_16(port);
+ RTE_PER_LCORE(_src_var) = src_var;
}
- copy_buf_to_pkt(&pkt_udp_hdr, sizeof(pkt_udp_hdr), pkt,
- sizeof(struct rte_ether_hdr) +
- sizeof(struct rte_ipv4_hdr));
if (unlikely(tx_pkt_split == TX_PKT_SPLIT_RND) || txonly_multi_flow)
update_pkt_header(pkt, pkt_len);
@@ -393,7 +395,7 @@ pkt_burst_transmit(struct fwd_stream *fs)
nb_tx = common_fwd_stream_transmit(fs, pkts_burst, nb_pkt);
if (txonly_multi_flow)
- RTE_PER_LCORE(_ip_var) -= nb_pkt - nb_tx;
+ RTE_PER_LCORE(_src_var) -= nb_pkt - nb_tx;
if (unlikely(nb_tx < nb_pkt)) {
if (verbose_level > 0 && fs->fwd_dropped == 0)
--
2.40.0.577.gac1e443424-goog
