net/igb: fix Tx descriptor status api

[dpdk.git] / drivers / net / e1000 / igb_rxtx.c

diff --git a/drivers/net/e1000/igb_rxtx.c b/drivers/net/e1000/igb_rxtx.c
index 5f729f2..22ca364 100644 (file)
--- a/drivers/net/e1000/igb_rxtx.c
+++ b/drivers/net/e1000/igb_rxtx.c
@@ -1826,14 +1826,15 @@ eth_igb_tx_descriptor_status(void *tx_queue, uint16_t offset)
 {
        struct igb_tx_queue *txq = tx_queue;
        volatile uint32_t *status;
-       uint32_t desc;
+       int32_t desc;
 
        if (unlikely(offset >= txq->nb_tx_desc))
                return -EINVAL;
 
-       desc = txq->tx_tail + offset;
-       if (desc >= txq->nb_tx_desc)
-               desc -= txq->nb_tx_desc;
+       desc = txq->tx_tail - offset - 1;
+       if (desc < 0)
+               desc += txq->nb_tx_desc;
+       desc = txq->sw_ring[desc].last_id;
 
        status = &txq->tx_ring[desc].wb.status;
        if (*status & rte_cpu_to_le_32(E1000_TXD_STAT_DD))