Re: [PATCH net-next 4/6] net: hip04: Don't free the tx skb when the buffer is not ready for xmit

Ding Tianhong
2015-04-16T06:26:21Z

On 2015/4/15 22:19, Arnd Bergmann wrote:
> On Wednesday 15 April 2015 20:30:06 Ding Tianhong wrote:
>> @@ -489,6 +487,8 @@ static int hip04_mac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
>>
>> /* Ensure tx_head update visible to tx reclaim */
>> smp_wmb();
>> + count++;
>> + priv->tx_head = TX_NEXT(tx_head);
>>
>>
>
> Something is wrong here, the comment does not match the code any more, because
> the smp_wmb() won't actually make the tx_head update visible.
>
> Arnd
>
Yes, the smp_wmb() could only make sure the tx buffer was ready to xmit.

> .