Re: [PATCH v5 net-next 2/5] net: implement support for low latency socket polling

[Eliezer Tamir <eliezer.tamir@linux.intel.com>]

On 28/05/2013 03:26, Eric Dumazet wrote:
> On Mon, 2013-05-27 at 10:44 +0300, Eliezer Tamir wrote:

>> diff --git a/include/net/sock.h b/include/net/sock.h
>> index 66772cf..c7c3ea6 100644
>> --- a/include/net/sock.h
>> +++ b/include/net/sock.h
>> @@ -281,6 +281,7 @@ struct cg_proto;
>>     *	@sk_error_report: callback to indicate errors (e.g. %MSG_ERRQUEUE)
>>     *	@sk_backlog_rcv: callback to process the backlog
>>     *	@sk_destruct: called at sock freeing time, i.e. when all refcnt == 0
>> +  *	@sk_napi_id: id of the last napi context to receive data for sk
>>    */
>>   struct sock {
>>   	/*
>> @@ -399,6 +400,9 @@ struct sock {
>>   	int			(*sk_backlog_rcv)(struct sock *sk,
>>   						  struct sk_buff *skb);
>>   	void                    (*sk_destruct)(struct sock *sk);
>> +#ifdef CONFIG_NET_LL_RX_POLL
>> +	unsigned int		sk_napi_id;
>> +#endif
>>   };
>
> I believe this is a bad choice for data locality.
>
> I would rather move it in the same cache line than sk_rxhash

I will move it to right after sk_rxhash.

-Eliezer