[dpdk-dev] [PATCH v2] test: avoid hang if queues are full and Tx fails

[Rakesh Kudurumalla <rkudurumalla@marvell.com>]

Current pmd_perf_autotest() in continuous mode tries
to enqueue MAX_TRAFFIC_BURST completely before starting
the test. Some drivers cannot accept complete
MAX_TRAFFIC_BURST even though rx+tx desc count can fit it.
This patch changes behaviour to stop enqueuing after few
retries.

Fixes: 002ade70e933 ("app/test: measure cycles per packet in Rx/Tx")
Cc: stable@dpdk.org

Signed-off-by: Rakesh Kudurumalla <rkudurumalla@marvell.com>
---
v2:
- Fixed commit message errors

 app/test/test_pmd_perf.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/app/test/test_pmd_perf.c b/app/test/test_pmd_perf.c
index 3a248d512c..0a95b408e8 100644
--- a/app/test/test_pmd_perf.c
+++ b/app/test/test_pmd_perf.c
@@ -456,6 +456,7 @@ main_loop(__rte_unused void *args)
 #define PACKET_SIZE 64
 #define FRAME_GAP 12
 #define MAC_PREAMBLE 8
+#define MAX_RETRY_COUNT 5
 	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
 	unsigned lcore_id;
 	unsigned i, portid, nb_rx = 0, nb_tx = 0;
@@ -463,6 +464,8 @@ main_loop(__rte_unused void *args)
 	int pkt_per_port;
 	uint64_t diff_tsc;
 	uint64_t packets_per_second, total_packets;
+	int retry_cnt = 0;
+	int free_pkt = 0;
 
 	lcore_id = rte_lcore_id();
 	conf = &lcore_conf[lcore_id];
@@ -480,10 +483,19 @@ main_loop(__rte_unused void *args)
 			nb_tx = RTE_MIN(MAX_PKT_BURST, num);
 			nb_tx = rte_eth_tx_burst(portid, 0,
 						&tx_burst[idx], nb_tx);
+			if (nb_tx == 0)
+				retry_cnt++;
 			num -= nb_tx;
 			idx += nb_tx;
+			if (retry_cnt == MAX_RETRY_COUNT) {
+				retry_cnt = 0;
+				break;
+			}
 		}
 	}
+	for (free_pkt = idx; free_pkt < (MAX_TRAFFIC_BURST*conf->nb_ports)
+			; free_pkt++)
+		rte_pktmbuf_free(tx_burst[free_pkt]);
 	printf("Total packets inject to prime ports = %u\n", idx);
 
 	packets_per_second = (link_mbps * 1000 * 1000) /
-- 
2.25.1