net/ixgbe: cleanup Tx buffers

Add support to the ixgbe driver for the API rte_eth_tx_done_cleanup
to force free consumed buffers on Tx ring.

Signed-off-by: Chenxu Di <chenxux.di@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>

drivers/net/ixgbe/ixgbe_ethdev.c

@@ -602,6 +602,7 @@ static const struct eth_dev_ops ixgbe_eth_dev_ops = {
 	.udp_tunnel_port_add  = ixgbe_dev_udp_tunnel_port_add,
 	.udp_tunnel_port_del  = ixgbe_dev_udp_tunnel_port_del,
 	.tm_ops_get           = ixgbe_tm_ops_get,
+	.tx_done_cleanup      = ixgbe_dev_tx_done_cleanup,
 };
 
 /*
@@ -650,6 +651,7 @@ static const struct eth_dev_ops ixgbevf_eth_dev_ops = {
 	.reta_query           = ixgbe_dev_rss_reta_query,
 	.rss_hash_update      = ixgbe_dev_rss_hash_update,
 	.rss_hash_conf_get    = ixgbe_dev_rss_hash_conf_get,
+	.tx_done_cleanup      = ixgbe_dev_tx_done_cleanup,
 };
 
 /* store statistics names and its offset in stats structure */

drivers/net/ixgbe/ixgbe_rxtx.c

@@ -2306,6 +2306,116 @@ ixgbe_tx_queue_release_mbufs(struct ixgbe_tx_queue *txq)
 	}
 }
 
+static int
+ixgbe_tx_done_cleanup_full(struct ixgbe_tx_queue *txq, uint32_t free_cnt)
+{
+	struct ixgbe_tx_entry *swr_ring = txq->sw_ring;
+	uint16_t i, tx_last, tx_id;
+	uint16_t nb_tx_free_last;
+	uint16_t nb_tx_to_clean;
+	uint32_t pkt_cnt;
+
+	/* Start free mbuf from the next of tx_tail */
+	tx_last = txq->tx_tail;
+	tx_id  = swr_ring[tx_last].next_id;
+
+	if (txq->nb_tx_free == 0 && ixgbe_xmit_cleanup(txq))
+		return 0;
+
+	nb_tx_to_clean = txq->nb_tx_free;
+	nb_tx_free_last = txq->nb_tx_free;
+	if (!free_cnt)
+		free_cnt = txq->nb_tx_desc;
+
+	/* Loop through swr_ring to count the amount of
+	 * freeable mubfs and packets.
+	 */
+	for (pkt_cnt = 0; pkt_cnt < free_cnt; ) {
+		for (i = 0; i < nb_tx_to_clean &&
+			pkt_cnt < free_cnt &&
+			tx_id != tx_last; i++) {
+			if (swr_ring[tx_id].mbuf != NULL) {
+				rte_pktmbuf_free_seg(swr_ring[tx_id].mbuf);
+				swr_ring[tx_id].mbuf = NULL;
+
+				/*
+				 * last segment in the packet,
+				 * increment packet count
+				 */
+				pkt_cnt += (swr_ring[tx_id].last_id == tx_id);
+			}
+
+			tx_id = swr_ring[tx_id].next_id;
+		}
+
+		if (txq->tx_rs_thresh > txq->nb_tx_desc -
+			txq->nb_tx_free || tx_id == tx_last)
+			break;
+
+		if (pkt_cnt < free_cnt) {
+			if (ixgbe_xmit_cleanup(txq))
+				break;
+
+			nb_tx_to_clean = txq->nb_tx_free - nb_tx_free_last;
+			nb_tx_free_last = txq->nb_tx_free;
+		}
+	}
+
+	return (int)pkt_cnt;
+}
+
+static int
+ixgbe_tx_done_cleanup_simple(struct ixgbe_tx_queue *txq,
+			uint32_t free_cnt)
+{
+	int i, n, cnt;
+
+	if (free_cnt == 0 || free_cnt > txq->nb_tx_desc)
+		free_cnt = txq->nb_tx_desc;
+
+	cnt = free_cnt - free_cnt % txq->tx_rs_thresh;
+
+	for (i = 0; i < cnt; i += n) {
+		if (txq->nb_tx_desc - txq->nb_tx_free < txq->tx_rs_thresh)
+			break;
+
+		n = ixgbe_tx_free_bufs(txq);
+
+		if (n == 0)
+			break;
+	}
+
+	return i;
+}
+
+static int
+ixgbe_tx_done_cleanup_vec(struct ixgbe_tx_queue *txq __rte_unused,
+			uint32_t free_cnt __rte_unused)
+{
+	return -ENOTSUP;
+}
+
+int
+ixgbe_dev_tx_done_cleanup(void *tx_queue, uint32_t free_cnt)
+{
+	struct ixgbe_tx_queue *txq = (struct ixgbe_tx_queue *)tx_queue;
+	if (txq->offloads == 0 &&
+#ifdef RTE_LIBRTE_SECURITY
+			!(txq->using_ipsec) &&
+#endif
+			txq->tx_rs_thresh >= RTE_PMD_IXGBE_TX_MAX_BURST) {
+		if (txq->tx_rs_thresh <= RTE_IXGBE_TX_MAX_FREE_BUF_SZ &&
+				(rte_eal_process_type() != RTE_PROC_PRIMARY ||
+					txq->sw_ring_v != NULL)) {
+			return ixgbe_tx_done_cleanup_vec(txq, free_cnt);
+		} else {
+			return ixgbe_tx_done_cleanup_simple(txq, free_cnt);
+		}
+	}
+
+	return ixgbe_tx_done_cleanup_full(txq, free_cnt);
+}
+
 static void __attribute__((cold))
 ixgbe_tx_free_swring(struct ixgbe_tx_queue *txq)
 {

drivers/net/ixgbe/ixgbe_rxtx.h

@@ -284,6 +284,7 @@ uint16_t ixgbe_recv_scattered_pkts_vec(void *rx_queue,
 int ixgbe_rx_vec_dev_conf_condition_check(struct rte_eth_dev *dev);
 int ixgbe_rxq_vec_setup(struct ixgbe_rx_queue *rxq);
 void ixgbe_rx_queue_release_mbufs_vec(struct ixgbe_rx_queue *rxq);
+int ixgbe_dev_tx_done_cleanup(void *tx_queue, uint32_t free_cnt);
 
 extern const uint32_t ptype_table[IXGBE_PACKET_TYPE_MAX];
 extern const uint32_t ptype_table_tn[IXGBE_PACKET_TYPE_TN_MAX];