[dpdk-dev] [PATCH v3 2/3] net/pcap: fix transmit return count in error conditions

[David Marchand <david.marchand@redhat.com>]

When a packet cannot be transmitted, the driver is supposed to free this
packet and report it as handled.
This is to prevent the application from retrying to send the same packet
and ending up in a liveloop since the driver will never manage to send
it.

Fixes: 49a0a2ffd5db ("net/pcap: fix possible mbuf double freeing")
Fixes: 6db141c91e1f ("pcap: support jumbo frames")
CC: stable@dpdk.org

Signed-off-by: David Marchand <david.marchand@redhat.com>
Acked-by: Ferruh Yigit <ferruh.yigit@intel.com>
---
Changelog since v1:
- restored the original behavior if pcap_sendpacket returns an error

---
 drivers/net/pcap/rte_eth_pcap.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/net/pcap/rte_eth_pcap.c b/drivers/net/pcap/rte_eth_pcap.c
index 470867d..bfc0756 100644
--- a/drivers/net/pcap/rte_eth_pcap.c
+++ b/drivers/net/pcap/rte_eth_pcap.c
@@ -354,7 +354,8 @@ eth_pcap_tx_dumper(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
 					mbuf->pkt_len,
 					RTE_ETHER_MAX_JUMBO_FRAME_LEN);
 
-				break;
+				rte_pktmbuf_free(mbuf);
+				continue;
 			}
 		}
 
@@ -373,7 +374,7 @@ eth_pcap_tx_dumper(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
 	dumper_q->tx_stat.bytes += tx_bytes;
 	dumper_q->tx_stat.err_pkts += nb_pkts - num_tx;
 
-	return num_tx;
+	return nb_pkts;
 }
 
 /*
@@ -439,7 +440,8 @@ eth_pcap_tx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
 					mbuf->pkt_len,
 					RTE_ETHER_MAX_JUMBO_FRAME_LEN);
 
-				break;
+				rte_pktmbuf_free(mbuf);
+				continue;
 			}
 		}
 
@@ -452,9 +454,9 @@ eth_pcap_tx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
 
 	tx_queue->tx_stat.pkts += num_tx;
 	tx_queue->tx_stat.bytes += tx_bytes;
-	tx_queue->tx_stat.err_pkts += nb_pkts - num_tx;
+	tx_queue->tx_stat.err_pkts += i - num_tx;
 
-	return num_tx;
+	return i;
 }
 
 /*
-- 
1.8.3.1