[PATCH net-next 05/11] net: hns3: add unlikely for error check

From: Peng Li
Date: Wed Jun 27 2018 - 23:43:54 EST


The first bd of a packet is invalid and invalid ring head for tx
IRQ is not offen, they may occur when there is error,
Add unlikely for error check branch is better for performance.

Signed-off-by: Peng Li <lipeng321@xxxxxxxxxx>
---
drivers/net/ethernet/hisilicon/hns3/hns3_enet.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
index 99bb6a8..1a68952 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
@@ -1917,7 +1917,7 @@ bool hns3_clean_tx_ring(struct hns3_enet_ring *ring, int budget)
if (is_ring_empty(ring) || head == ring->next_to_clean)
return true; /* no data to poll */

- if (!is_valid_clean_head(ring, head)) {
+ if (unlikely(!is_valid_clean_head(ring, head))) {
netdev_err(netdev, "wrong head (%d, %d-%d)\n", head,
ring->next_to_use, ring->next_to_clean);

@@ -2174,7 +2174,7 @@ static int hns3_handle_rx_bd(struct hns3_enet_ring *ring,
bd_base_info = le32_to_cpu(desc->rx.bd_base_info);

/* Check valid BD */
- if (!hnae_get_bit(bd_base_info, HNS3_RXD_VLD_B))
+ if (unlikely(!hnae_get_bit(bd_base_info, HNS3_RXD_VLD_B)))
return -EFAULT;

va = (unsigned char *)desc_cb->buf + desc_cb->page_offset;
--
2.9.3