# RE: \[PATCH net-next\] mlx4: dont orphan skbs in mlx4\_en\_xmit()

- From: Yevgeny Petrilin \<hidden\>
- Date: 2012-09-30 06:58:41 
- List: netdev
- Page: https://ratatoskr.run/netdev/2012/09/10905247
- Thread: https://ratatoskr.run/netdev/2012/09/10904103/t.md

```text
Acked-by: Yevgeny Petrilin <redacted>

> -----Original Message-----
> From: Eric Dumazet [mailto:<redacted>]
> Sent: Friday, September 28, 2012 7:54 PM
> To: Yevgeny Petrilin
> Cc: David Miller; netdev; Or Gerlitz
> Subject: [PATCH net-next] mlx4: dont orphan skbs in mlx4_en_xmit()
> 
> From: Eric Dumazet <redacted>
> 
> After commit e22979d96a55d (mlx4_en: Moving to Interrupts for TX
> completions) we no longer need to orphan skbs in mlx4_en_xmit()
> since skb wont stay a long time in TX ring before their release.
> 
> Orphaning skbs in ndo_start_xmit() should be avoided as much as
> possible, since it breaks TCP Small Queue or other flow control
> mechanisms (per socket limits)
> 
> Signed-off-by: Eric Dumazet <redacted>
> Cc: Yevgeny Petrilin <redacted>
> Cc: Or Gerlitz <redacted>
> ---
>  drivers/net/ethernet/mellanox/mlx4/en_tx.c |    4 ----
>  1 file changed, 4 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx4/en_tx.c
> b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
> index 10bba09..c10e3a6 100644
> --- a/drivers/net/ethernet/mellanox/mlx4/en_tx.c
> +++ b/drivers/net/ethernet/mellanox/mlx4/en_tx.c
> @@ -712,10 +712,6 @@ netdev_tx_t mlx4_en_xmit(struct sk_buff *skb, struct net_device *dev)
>  	if (bounce)
>  		tx_desc = mlx4_en_bounce_to_desc(priv, ring, index, desc_size);
> 
> -	/* Run destructor before passing skb to HW */
> -	if (likely(!skb_shared(skb)))
> -		skb_orphan(skb);
> -
>  	if (ring->bf_enabled && desc_size <= MAX_BF && !bounce && !vlan_tag) {
>  		*(__be32 *) (&tx_desc->ctrl.vlan_tag) |= cpu_to_be32(ring->doorbell_qpn);
>  		op_own |= htonl((bf_index & 0xffff) << 8);
> 

```
