From: Eric Dumazet Date: Wed, 30 Sep 2009 13:03:33 +0000 (+0000) Subject: pktgen: Avoid dirtying skb->users when txq is full X-Git-Tag: v2.6.33-rc1~388^2~943 X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=0835acfe72e43b2f9bd46ec8c0d219e94c3525e0;p=~emulex%2Finfiniband.git pktgen: Avoid dirtying skb->users when txq is full We can avoid two atomic ops on skb->users if packet is not going to be sent to the device (because hardware txqueue is full) Signed-off-by: Eric Dumazet Acked-by: Stephen Hemminger Signed-off-by: David S. Miller --- diff --git a/net/core/pktgen.c b/net/core/pktgen.c index b69455217ed..e856ab0d074 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -3441,12 +3441,14 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev) txq = netdev_get_tx_queue(odev, queue_map); __netif_tx_lock_bh(txq); - atomic_inc(&(pkt_dev->skb->users)); - if (unlikely(netif_tx_queue_stopped(txq) || netif_tx_queue_frozen(txq))) + if (unlikely(netif_tx_queue_stopped(txq) || netif_tx_queue_frozen(txq))) { ret = NETDEV_TX_BUSY; - else - ret = (*xmit)(pkt_dev->skb, odev); + pkt_dev->last_ok = 0; + goto unlock; + } + atomic_inc(&(pkt_dev->skb->users)); + ret = (*xmit)(pkt_dev->skb, odev); switch (ret) { case NETDEV_TX_OK: @@ -3468,6 +3470,7 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev) atomic_dec(&(pkt_dev->skb->users)); pkt_dev->last_ok = 0; } +unlock: __netif_tx_unlock_bh(txq); /* If pkt_dev->count is zero, then run forever */