From: Eilon Greenstein Date: Mon, 2 Mar 2009 07:59:24 +0000 (+0000) Subject: bnx2x: Reduce the likelihood of smb_mb X-Git-Tag: v2.6.30-rc1~662^2~406 X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=6044735d8ddd96bf23cf975bae8729c65479aa14;p=~emulex%2Finfiniband.git bnx2x: Reduce the likelihood of smb_mb As the comment explains, this smb_mb is needed only if the queue is stopped (which is unlikely) so the barrier can be moved to that location Signed-off-by: Eilon Greenstein Signed-off-by: David S. Miller --- diff --git a/drivers/net/bnx2x_main.c b/drivers/net/bnx2x_main.c index 5954bed6065..fbd0f88fc81 100644 --- a/drivers/net/bnx2x_main.c +++ b/drivers/net/bnx2x_main.c @@ -916,18 +916,19 @@ static void bnx2x_tx_int(struct bnx2x_fastpath *fp, int work) fp->tx_pkt_cons = sw_cons; fp->tx_bd_cons = bd_cons; - /* Need to make the tx_bd_cons update visible to start_xmit() - * before checking for netif_tx_queue_stopped(). Without the - * memory barrier, there is a small possibility that start_xmit() - * will miss it and cause the queue to be stopped forever. - */ - smp_mb(); - /* TBD need a thresh? */ if (unlikely(netif_tx_queue_stopped(txq))) { __netif_tx_lock(txq, smp_processor_id()); + /* Need to make the tx_bd_cons update visible to start_xmit() + * before checking for netif_tx_queue_stopped(). Without the + * memory barrier, there is a small possibility that + * start_xmit() will miss it and cause the queue to be stopped + * forever. + */ + smp_mb(); + if ((netif_tx_queue_stopped(txq)) && (bp->state == BNX2X_STATE_OPEN) && (bnx2x_tx_avail(fp) >= MAX_SKB_FRAGS + 3))