Subject: Re: [PATCH 1/7] net: refactor __netif_receive_skb_core

From: Alexander Duyck <[email-masked]>
Date: Wed, 15 Apr 2015 06:28:22 -0700

On 04/15/2015 05:44 AM, David Laight wrote:
> From: Alexander Duyck
>> Sent: 10 April 2015 20:56
>> On 04/10/2015 05:15 AM, Pablo Neira Ayuso wrote:
>>> +another_round:
>>> +	ret = __netif_receive_skb_ingress(skb, pfmemalloc, orig_dev);
>>> +	switch (ret) {
>>> +	case NET_RX_SUCCESS:
>>> +	case NET_RX_DROP:
>>> +		break;
>>> +	case __NET_RX_ANOTHER_ROUND:
>>> +		goto another_round;
>>> +	}
>>>   	rcu_read_unlock();
>>> +
>>>   	return ret;
>>>   }
>>>
>>>
>>
>> Couldn't this just be done as a do while?  It would probably be easier
>> to read and there wouldn't be any need for the another_round label anymore.
>
> Or an infinite loop with a break at the bottom, as in:
> 	for (;;) {
> 		switch (...) {
> 		case again:
> 			continue;
> 		default:
> 			break;
> 		}
> 		break;
> 	}
>
> 	David
>

That is even more complicated.  What I was thinking was
	do {
		ret = __netif_receive_skb_ingress(skb, pfmemalloc,
						  orig_dev);
	} while (ret == __NET_RX_ANOTHER_ROUND);

Either that or the switch could just be replaced with a if statement 
since the only case that really goes anywhere is __NET_RX_ANOTHER_ROUND 
and everything else just exits anyway.  I had just suggested a do/while 
since that lets the goto be dropped, but an if would allow for avoiding 
any unnecessary indentation on the call to __netif_receive_skb_ingress.

- Alex