netdev - [PATCH net-next 1/1] forcedeth: optimize the rx with likely

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Date:   Tue, 26 Dec 2017 01:22:50 -0500
From:   Zhu Yanjun <yanjun.zhu@...cle.com>
To:     keescook@...omium.org, netdev@...r.kernel.org
Subject: [PATCH net-next 1/1] forcedeth: optimize the rx with likely

In the rx fastpath, the function netdev_alloc_skb rarely fails.
Therefore, a likely() optimization is added to this error check
conditional.

CC: Srinivas Eeda <srinivas.eeda@...cle.com>
CC: Joe Jin <joe.jin@...cle.com>
CC: Junxiao Bi <junxiao.bi@...cle.com>
Signed-off-by: Zhu Yanjun <yanjun.zhu@...cle.com>
---
 drivers/net/ethernet/nvidia/forcedeth.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/nvidia/forcedeth.c b/drivers/net/ethernet/nvidia/forcedeth.c
index 49d6d78..a79b9f8 100644
--- a/drivers/net/ethernet/nvidia/forcedeth.c
+++ b/drivers/net/ethernet/nvidia/forcedeth.c
@@ -1817,7 +1817,7 @@ static int nv_alloc_rx(struct net_device *dev)
 
 	while (np->put_rx.orig != less_rx) {
 		struct sk_buff *skb = netdev_alloc_skb(dev, np->rx_buf_sz + NV_RX_ALLOC_PAD);
-		if (skb) {
+		if (likely(skb)) {
 			np->put_rx_ctx->skb = skb;
 			np->put_rx_ctx->dma = dma_map_single(&np->pci_dev->dev,
 							     skb->data,
@@ -1858,7 +1858,7 @@ static int nv_alloc_rx_optimized(struct net_device *dev)
 
 	while (np->put_rx.ex != less_rx) {
 		struct sk_buff *skb = netdev_alloc_skb(dev, np->rx_buf_sz + NV_RX_ALLOC_PAD);
-		if (skb) {
+		if (likely(skb)) {
 			np->put_rx_ctx->skb = skb;
 			np->put_rx_ctx->dma = dma_map_single(&np->pci_dev->dev,
 							     skb->data,
-- 
2.7.4