Re: [PATCH v2] net-fq: Add WARN_ON check for null flow.

[Ben Greear <greearb@candelatech.com>]

On 06/07/2018 04:59 PM, Cong Wang wrote:
> On Thu, Jun 7, 2018 at 4:48 PM,  <greearb@candelatech.com> wrote:
>> diff --git a/include/net/fq_impl.h b/include/net/fq_impl.h
>> index be7c0fa..cb911f0 100644
>> --- a/include/net/fq_impl.h
>> +++ b/include/net/fq_impl.h
>> @@ -78,7 +78,10 @@ static struct sk_buff *fq_tin_dequeue(struct fq *fq,
>>                         return NULL;
>>         }
>>
>> -       flow = list_first_entry(head, struct fq_flow, flowchain);
>> +       flow = list_first_entry_or_null(head, struct fq_flow, flowchain);
>> +
>> +       if (WARN_ON_ONCE(!flow))
>> +               return NULL;
>
> This does not make sense either. list_first_entry_or_null()
> returns NULL only when the list is empty, but we already check
> list_empty() right before this code, and it is protected by fq->lock.
>

Nevermind then.

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com