bnx2x: change smp_mb() comment to conform the true

Access to fp->tx_bp_prod is protected by __netif_tx_lock,
smp_mb() is not needed for that.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 2 deletions

diff --git a/drivers/net/bnx2x_main.c b/drivers/net/bnx2x_main.c
index ae62b67aa597..6c042a72d6cc 100644
--- a/drivers/net/bnx2x_main.c
+++ b/drivers/net/bnx2x_main.c
@@ -11428,9 +11428,12 @@ static netdev_tx_t bnx2x_start_xmit(struct sk_buff *skb, struct net_device *dev)
 
         if (unlikely(bnx2x_tx_avail(fp) < MAX_SKB_FRAGS + 3)) {
                 netif_tx_stop_queue(txq);
-                /* We want bnx2x_tx_int to "see" the updated tx_bd_prod
-                   if we put Tx into XOFF state. */
+
+                /* paired memory barrier is in bnx2x_tx_int(), we have to keep
+                 * ordering of set_bit() in netif_tx_stop_queue() and read of
+                 * fp->bd_tx_cons */
                 smp_mb();
+
                 fp->eth_q_stats.driver_xoff++;
                 if (bnx2x_tx_avail(fp) >= MAX_SKB_FRAGS + 3)
                         netif_tx_wake_queue(txq);