From: Eric Dumazet <[email protected]>
When multiple skb are TX-completed in a row, we might incorrectly keep
a timestamp of a prior skb and cause extra work.
Fixes: ec693d47010e8 ("net/mlx4_en: Add HW timestamping (TS) support")
Signed-off-by: Eric Dumazet <[email protected]>
Willem de Bruijn <[email protected]>
---
drivers/net/ethernet/mellanox/mlx4/en_tx.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c
b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
index c0d7b7296236..a386f047c1af 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
@@ -405,7 +405,6 @@ static bool mlx4_en_process_tx_cq(struct net_device *dev,
u32 packets = 0;
u32 bytes = 0;
int factor = priv->cqe_factor;
- u64 timestamp = 0;
int done = 0;
int budget = priv->tx_work_limit;
u32 last_nr_txbb;
@@ -445,9 +444,12 @@ static bool mlx4_en_process_tx_cq(struct net_device *dev,
new_index = be16_to_cpu(cqe->wqe_index) & size_mask;
do {
+ u64 timestamp = 0;
+
txbbs_skipped += last_nr_txbb;
ring_index = (ring_index + last_nr_txbb) & size_mask;
- if (ring->tx_info[ring_index].ts_requested)
+
+ if (unlikely(ring->tx_info[ring_index].ts_requested))
timestamp = mlx4_en_get_cqe_ts(cqe);
/* free next descriptor */