Re: [PATCH net-next-2.6] vlan: lockless transmit path

Jesse Gross
2010-11-11T18:56:15Z

On Thu, Nov 11, 2010 at 9:52 AM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> Le jeudi 11 novembre 2010 à 09:40 -0800, Jesse Gross a écrit :
>
>> If we're only allocating a single queue then we should also drop
>> vlan_dev_select_queue() and the netdev_ops that call it.  If the
>> underlying device is multiqueue and has its own select_queue function
>> then it can pick a queue number that is larger than what the vlan
>> device has.  The problem will be caught by dev_cap_txqueue() but it's
>> not right and it would also be nice to get rid of half of those
>> netdev_ops.
>
> Hmm, you refer to old kernels dont you ?
>
> My patch is for net-next

Well, I was referring to checked-in code.

>
> The plan is that after last Tom Herbert patches, dev_pick_tx()  wont
> call do_select_queue() on mono queue device.
>
> http://patchwork.ozlabs.org/patch/70369/

Before Tom's patch, a warning will be generated if a single queue vlan
device is stacked on top of a multiqueue physical device that
implements ndo_select_queue(). After Tom's patch, we avoid the
warning so vlan_dev_select_queue() is merely dead code. Either way,
what's the benefit in keeping it?

>
>
> This logicaly is a second cleanup patch I believe.

I'm not arguing against your patch, I just think it should go a step further.