ethdev: fix check of threshold for Tx freeing

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

diff --git a/drivers/net/e1000/em_rxtx.c b/drivers/net/e1000/em_rxtx.c
index fdc825f..38f5c3b 100644 (file)
--- a/drivers/net/e1000/em_rxtx.c
+++ b/drivers/net/e1000/em_rxtx.c
@@ -182,7 +182,9 @@ struct em_tx_queue {
        volatile uint32_t      *tdt_reg_addr; /**< Address of TDT register. */
        uint16_t               nb_tx_desc;    /**< number of TX descriptors. */
        uint16_t               tx_tail;  /**< Current value of TDT register. */
-       uint16_t               tx_free_thresh;/**< minimum TX before freeing. */
+       /**< Start freeing TX buffers if there are less free descriptors than
+            this value. */
+       uint16_t               tx_free_thresh;
        /**< Number of TX descriptors to use before RS bit is set. */
        uint16_t               tx_rs_thresh;
        /** Number of TX descriptors used since RS bit was set. */
@@ -418,9 +420,8 @@ eth_em_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
        txe = &sw_ring[tx_id];
 
        /* Determine if the descriptor ring needs to be cleaned. */
-       if ((txq->nb_tx_desc - txq->nb_tx_free) > txq->tx_free_thresh) {
+        if (txq->nb_tx_free < txq->tx_free_thresh)
                em_xmit_cleanup(txq);
-       }
 
        /* TX loop */
        for (nb_tx = 0; nb_tx < nb_pkts; nb_tx++) {