ixgbe: fix Tx hang when RS distance exceeds HW limit

[dpdk.git] / drivers / net / ixgbe / ixgbe_rxtx.c

diff --git a/drivers/net/ixgbe/ixgbe_rxtx.c b/drivers/net/ixgbe/ixgbe_rxtx.c
index 5561195..ca6fb69 100644 (file)
--- a/drivers/net/ixgbe/ixgbe_rxtx.c
+++ b/drivers/net/ixgbe/ixgbe_rxtx.c
@@ -572,7 +572,7 @@ ixgbe_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
        struct ixgbe_tx_entry *sw_ring;
        struct ixgbe_tx_entry *txe, *txn;
        volatile union ixgbe_adv_tx_desc *txr;
-       volatile union ixgbe_adv_tx_desc *txd;
+       volatile union ixgbe_adv_tx_desc *txd, *txp;
        struct rte_mbuf     *tx_pkt;
        struct rte_mbuf     *m_seg;
        uint64_t buf_dma_addr;
@@ -595,6 +595,7 @@ ixgbe_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
        txr     = txq->tx_ring;
        tx_id   = txq->tx_tail;
        txe = &sw_ring[tx_id];
+       txp = NULL;
 
        /* Determine if the descriptor ring needs to be cleaned. */
        if (txq->nb_tx_free < txq->tx_free_thresh)
@@ -638,6 +639,12 @@ ixgbe_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
                 */
                nb_used = (uint16_t)(tx_pkt->nb_segs + new_ctx);
 
+               if (txp != NULL &&
+                               nb_used + txq->nb_tx_used >= txq->tx_rs_thresh)
+                       /* set RS on the previous packet in the burst */
+                       txp->read.cmd_type_len |=
+                               rte_cpu_to_le_32(IXGBE_TXD_CMD_RS);
+
                /*
                 * The number of descriptors that must be allocated for a
                 * packet is the number of segments of that packet, plus 1
@@ -840,10 +847,18 @@ ixgbe_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 
                        /* Update txq RS bit counters */
                        txq->nb_tx_used = 0;
-               }
+                       txp = NULL;
+               } else
+                       txp = txd;
+
                txd->read.cmd_type_len |= rte_cpu_to_le_32(cmd_type_len);
        }
+
 end_of_tx:
+       /* set RS on last packet in the burst */
+       if (txp != NULL)
+               txp->read.cmd_type_len |= rte_cpu_to_le_32(IXGBE_TXD_CMD_RS);
+
        rte_wmb();
 
        /*
@@ -2019,9 +2034,16 @@ ixgbe_dev_tx_queue_setup(struct rte_eth_dev *dev,
                        tx_conf->tx_free_thresh : DEFAULT_TX_FREE_THRESH);
        if (tx_rs_thresh >= (nb_desc - 2)) {
                PMD_INIT_LOG(ERR, "tx_rs_thresh must be less than the number "
-                            "of TX descriptors minus 2. (tx_rs_thresh=%u "
-                            "port=%d queue=%d)", (unsigned int)tx_rs_thresh,
-                            (int)dev->data->port_id, (int)queue_idx);
+                       "of TX descriptors minus 2. (tx_rs_thresh=%u "
+                       "port=%d queue=%d)", (unsigned int)tx_rs_thresh,
+                       (int)dev->data->port_id, (int)queue_idx);
+               return -(EINVAL);
+       }
+       if (tx_rs_thresh > DEFAULT_TX_RS_THRESH) {
+               PMD_INIT_LOG(ERR, "tx_rs_thresh must be less or equal than %u. "
+                       "(tx_rs_thresh=%u port=%d queue=%d)",
+                       DEFAULT_TX_RS_THRESH, (unsigned int)tx_rs_thresh,
+                       (int)dev->data->port_id, (int)queue_idx);
                return -(EINVAL);
        }
        if (tx_free_thresh >= (nb_desc - 3)) {