[PATCH v3 2/3] examples/dma: fix Tx drop statistic is not collected

[Chengwen Feng <fengchengwen@huawei.com>]

The Tx drop statistic was designed to collected by
rte_eth_dev_tx_buffer mechanism, but the application uses
rte_eth_tx_burst to send packets and this lead the Tx drop statistic
was not collected.

This patch removes rte_eth_dev_tx_buffer mechanism to fix the problem.

Fixes: 632bcd9b5d4f ("examples/ioat: print statistics")
Cc: stable@dpdk.org

Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
---
 examples/dma/dmafwd.c | 27 +++++----------------------
 1 file changed, 5 insertions(+), 22 deletions(-)

diff --git a/examples/dma/dmafwd.c b/examples/dma/dmafwd.c
index a03ca05129..dd576bcf77 100644
--- a/examples/dma/dmafwd.c
+++ b/examples/dma/dmafwd.c
@@ -122,7 +122,6 @@ static uint32_t max_frame_size;
 /* ethernet addresses of ports */
 static struct rte_ether_addr dma_ports_eth_addr[RTE_MAX_ETHPORTS];
 
-static struct rte_eth_dev_tx_buffer *tx_buffer[RTE_MAX_ETHPORTS];
 struct rte_mempool *dma_pktmbuf_pool;
 
 /* Print out statistics for one port. */
@@ -484,10 +483,13 @@ dma_tx_port(struct rxtx_port_config *tx_config)
 
 		port_statistics.tx[tx_config->rxtx_port] += nb_tx;
 
-		/* Free any unsent packets. */
-		if (unlikely(nb_tx < nb_dq))
+		if (unlikely(nb_tx < nb_dq)) {
+			port_statistics.tx_dropped[tx_config->rxtx_port] +=
+				(nb_dq - nb_tx);
+			/* Free any unsent packets. */
 			rte_mempool_put_bulk(dma_pktmbuf_pool,
 			(void *)&mbufs[nb_tx], nb_dq - nb_tx);
+		}
 	}
 }
 /* >8 End of transmitting packets from dmadev. */
@@ -970,25 +972,6 @@ port_init(uint16_t portid, struct rte_mempool *mbuf_pool, uint16_t nb_queues)
 			"rte_eth_tx_queue_setup:err=%d,port=%u\n",
 			ret, portid);
 
-	/* Initialize TX buffers */
-	tx_buffer[portid] = rte_zmalloc_socket("tx_buffer",
-			RTE_ETH_TX_BUFFER_SIZE(MAX_PKT_BURST), 0,
-			rte_eth_dev_socket_id(portid));
-	if (tx_buffer[portid] == NULL)
-		rte_exit(EXIT_FAILURE,
-			"Cannot allocate buffer for tx on port %u\n",
-			portid);
-
-	rte_eth_tx_buffer_init(tx_buffer[portid], MAX_PKT_BURST);
-
-	ret = rte_eth_tx_buffer_set_err_callback(tx_buffer[portid],
-		rte_eth_tx_buffer_count_callback,
-		&port_statistics.tx_dropped[portid]);
-	if (ret < 0)
-		rte_exit(EXIT_FAILURE,
-			"Cannot set error callback for tx buffer on port %u\n",
-			portid);
-
 	/* Start device. 8< */
 	ret = rte_eth_dev_start(portid);
 	if (ret < 0)
-- 
2.33.0