[dpdk-dev] [PATCH] [new]ixgbe:set txep.mbuf to NULL when calling ixgbe_tx_free_bufs

[hepeng <xnhp0320@icloud.com>]

In *ixgbe_tx_free_bufs*, after recycling some tx entries, one should set their mbuf pointers to NULL.

The first path is not correct, the txep->mbuf should be set to NULL no matter if it is recycled into mempool
Signed-off-by: hepeng <xnhp0320@icloud.com>
---
 drivers/net/ixgbe/ixgbe_rxtx_vec.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ixgbe/ixgbe_rxtx_vec.c b/drivers/net/ixgbe/ixgbe_rxtx_vec.c
index 1c16dec..e7ce740 100644
--- a/drivers/net/ixgbe/ixgbe_rxtx_vec.c
+++ b/drivers/net/ixgbe/ixgbe_rxtx_vec.c
@@ -612,6 +612,7 @@ ixgbe_tx_free_bufs(struct ixgbe_tx_queue *txq)
 	 */
 	txep = &txq->sw_ring_v[txq->tx_next_dd - (n - 1)];
 	m = __rte_pktmbuf_prefree_seg(txep[0].mbuf);
+    txep[0].mbuf = NULL;
 	if (likely(m != NULL)) {
 		free[0] = m;
 		nb_free = 1;
@@ -632,11 +633,21 @@ ixgbe_tx_free_bufs(struct ixgbe_tx_queue *txq)
 	} else {
 		for (i = 1; i < n; i++) {
 			m = __rte_pktmbuf_prefree_seg(txep[i].mbuf);
-			if (m != NULL)
+			if (m != NULL) {
 				rte_mempool_put(m->pool, m);
+            }
 		}
 	}
 
+    /*
+     * No matter the mbufs have been put back to mempool or not,
+     * we should set the txep[i].mbuf to NULL
+     */
+
+    for( i = 1; i < n; i++) {
+        txep[i].mbuf = NULL;
+    }
+
 	/* buffers were freed, update counters */
 	txq->nb_tx_free = (uint16_t)(txq->nb_tx_free + txq->tx_rs_thresh);
 	txq->tx_next_dd = (uint16_t)(txq->tx_next_dd + txq->tx_rs_thresh);
-- 
1.9.1