bnx2x: change smp_mb() comment to conform the true
authorStanislaw Gruszka <sgruszka@redhat.com>
Tue, 9 Mar 2010 06:55:02 +0000 (06:55 +0000)
committerDavid S. Miller <davem@davemloft.net>
Mon, 15 Mar 2010 22:47:01 +0000 (15:47 -0700)
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>
drivers/net/bnx2x_main.c

index ae62b67..6c042a7 100644 (file)
@@ -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);