On Mon, Mar 13, 2017 at 4:40 PM, Alexei Starovoitov
<alexei.starovoi...@gmail.com> wrote:
> On Mon, Mar 13, 2017 at 04:28:04PM -0700, Eric Dumazet wrote:
>> On Mon, Mar 13, 2017 at 4:21 PM, Alexei Starovoitov
>> <alexei.starovoi...@gmail.com> wrote:
>> >
>> > is it once in the beginning only? If so then why that
>> > 'if (!ring->page_cache.index)' check is done for every packet?
>>
>>
>>
>> You did not really read the patch, otherwise you would not ask these
>> questions.
>
> please explain. I see
> + if (!ring->page_cache.index) {
> + npage = mlx4_alloc_page(priv, ring,
> which is done for every packet that goes via XDP_TX.
>
Well, we do for all packets, even on hosts not running XDP:
if (xdp_prog) { ...
...
Then :
if (doorbell_pending))
mlx4_en_xmit_doorbell(priv->tx_ring[TX_XDP][cq->ring]);
And nobody complained of few additional instructions.
Should I had, very loudly ?
>> Test it, and if you find a regression, shout loudly.
>
> that's not how it works. It's a job of submitter to prove
> that additional code doesn't cause regressions especially
> when there are legitimate concerns.
I have no easy way to test XDP. I have never used it and am not
planning to use it any time soon.
Does it mean I no longer can participate to linux dev ?
Nice to hear Alexei.
