Re: [PATCH 1/5] net/fm10k: remove limit of fm10k_xmit_pkts_vec burst size

[Bruce Richardson <bruce.richardson@intel.com>]

On Fri, Feb 24, 2017 at 09:32:56AM +0000, Bruce Richardson wrote:
> On Fri, Feb 24, 2017 at 04:48:17PM +0800, Zhiyong Yang wrote:
> > To add a wrapper function fm10k_xmit_pkts_vec_simple to remove
> > the limit of tx burst size. The patch makes fm10k vec function
> > an best effort to transmit the pkts in the consistent behavior
> > like fm10k_xmit_pkts does that.
> > 
> > Cc: Jing Chen <jing.d.chen@intel.com>
> > 
> > Signed-off-by: Zhiyong Yang <zhiyong.yang@intel.com>
> > ---
> >  drivers/net/fm10k/fm10k_ethdev.c | 27 ++++++++++++++++++++++++++-
> >  1 file changed, 26 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/net/fm10k/fm10k_ethdev.c b/drivers/net/fm10k/fm10k_ethdev.c
> > index c4fe746..e9b6254 100644
> > --- a/drivers/net/fm10k/fm10k_ethdev.c
> > +++ b/drivers/net/fm10k/fm10k_ethdev.c
> > @@ -2741,6 +2741,31 @@ fm10k_check_ftag(struct rte_devargs *devargs)
> >  	return 1;
> >  }
> >  
> > +static uint16_t
> > +fm10k_xmit_pkts_vec_simple(void *tx_queue, struct rte_mbuf **tx_pkts,
> > +			   uint16_t nb_pkts)
> > +{
> > +	uint16_t nb_tx = 0;
> > +	struct fm10k_tx_queue *txq = (struct fm10k_tx_queue *)tx_queue;
> > +
> > +	if (likely(nb_pkts <= txq->rs_thresh))
> > +		return fm10k_xmit_pkts_vec(tx_queue, tx_pkts, nb_pkts);
> > +
> > +	/* transmit in chunks of at least txq->rs_thresh */
> > +	while (nb_pkts) {
> > +		uint16_t ret, num;
> > +
> > +		num = (uint16_t)RTE_MIN(nb_pkts, txq->rs_thresh);
> > +		ret = fm10k_xmit_pkts_vec(tx_queue, &tx_pkts[nb_tx], num);
> > +		nb_tx += ret;
> > +		nb_pkts -= ret;
> > +		if (ret < num)
> > +			break;
> > +	}
> > +
> > +	return nb_tx;
> > +}
> > +
> >  static void __attribute__((cold))
> >  fm10k_set_tx_function(struct rte_eth_dev *dev)
> >  {
> > @@ -2766,7 +2791,7 @@ fm10k_set_tx_function(struct rte_eth_dev *dev)
> >  			txq = dev->data->tx_queues[i];
> >  			fm10k_txq_vec_setup(txq);
> >  		}
> > -		dev->tx_pkt_burst = fm10k_xmit_pkts_vec;
> > +		dev->tx_pkt_burst = fm10k_xmit_pkts_vec_simple;
> >  		dev->tx_pkt_prepare = NULL;
> >  	} else {
> 
> The names of the functions do not look right to me. I don't think the
> suffic "_simple" is suitable for describing the functionality of the
> wrapper function vs the original function. I think instead that the
> original function should be renamed to indicate that it is only handles
> a fixed size burst of pkts, and the new wrapper function takes the
> original name. For example:
> 
> 	fm10k_xmit_fixed_burst_vec (original fn)
> 	fm10k_xmit_pkts_vec (new fn)
>
This comment applies for the other patches in the set too.

/Bruce