> -----Original Message-----
> From: David Marchand <david.march...@redhat.com>
> Sent: Thursday, April 8, 2021 4:40 PM
> To: Yigit, Ferruh <ferruh.yi...@intel.com>
> Cc: Rong, Leyi <leyi.r...@intel.com>; Zhang, Qi Z <qi.z.zh...@intel.com>;
> Xing,
> Beilei <beilei.x...@intel.com>; dev <dev@dpdk.org>
> Subject: Re: [dpdk-dev] [PATCH] net/i40e: add Tx preparation for vector data
> path
>
> On Wed, Apr 7, 2021 at 6:40 PM Ferruh Yigit <ferruh.yi...@intel.com> wrote:
> >
> > On 3/31/2021 9:53 AM, Leyi Rong wrote:
> > > Fill up dev->tx_pkt_prepare to i40e_pkt_prepare when on vector and
> > > simple data path selection, as the sanity check is needed ideally.
> > >
> > > Signed-off-by: Leyi Rong <leyi.r...@intel.com>
> > > ---
> > > drivers/net/i40e/i40e_rxtx.c | 2 +-
> > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/net/i40e/i40e_rxtx.c
> > > b/drivers/net/i40e/i40e_rxtx.c index 61cb204be2..b3d7765e3b 100644
> > > --- a/drivers/net/i40e/i40e_rxtx.c
> > > +++ b/drivers/net/i40e/i40e_rxtx.c
> > > @@ -3412,7 +3412,7 @@ i40e_set_tx_function(struct rte_eth_dev *dev)
> > > PMD_INIT_LOG(DEBUG, "Simple tx finally be used.");
> > > dev->tx_pkt_burst = i40e_xmit_pkts_simple;
> > > }
> > > - dev->tx_pkt_prepare = NULL;
> > > + dev->tx_pkt_prepare = i40e_prep_pkts;
> > > } else {
> > > PMD_INIT_LOG(DEBUG, "Xmit tx finally be used.");
> > > dev->tx_pkt_burst = i40e_xmit_pkts;
> > >
> >
> > It seems prepare function is doing some sanity checks before handing
> > packets to the HW.
> > So with this change all Tx paths calls the same Tx prepare function,
> > if so why not set the function pointer outside of the if block,
> > instead of setting it in both legs of the if/else? This clarifies that Tx
> > prepare
> used always.
>
> As I said earlier, what is the point of setting it in ethdev.c too?
> It would be more consistent to have this in a single location.
>
> drivers/net/i40e/i40e_ethdev.c: dev->tx_pkt_burst = i40e_xmit_pkts;
> drivers/net/i40e/i40e_ethdev.c: dev->tx_pkt_prepare = i40e_prep_pkts;
> drivers/net/i40e/i40e_ethdev_vf.c: eth_dev->tx_pkt_burst =
> &i40e_xmit_pkts;
> drivers/net/i40e/i40e_rxtx.c: if (dev->tx_pkt_burst ==
> i40e_xmit_pkts_vec_avx512) {
> drivers/net/i40e/i40e_rxtx.c: if (dev->tx_pkt_burst ==
> i40e_xmit_pkts_vec_avx2 ||
> drivers/net/i40e/i40e_rxtx.c: dev->tx_pkt_burst ==
> i40e_xmit_pkts_vec) {
> drivers/net/i40e/i40e_rxtx.c:
> dev->tx_pkt_burst = i40e_xmit_pkts_vec_avx512;
> drivers/net/i40e/i40e_rxtx.c:
> dev->tx_pkt_burst = use_avx2 ?
> drivers/net/i40e/i40e_rxtx.c: dev->tx_pkt_burst =
> i40e_xmit_pkts_simple;
> drivers/net/i40e/i40e_rxtx.c: dev->tx_pkt_prepare = NULL;
> drivers/net/i40e/i40e_rxtx.c: dev->tx_pkt_burst = i40e_xmit_pkts;
> drivers/net/i40e/i40e_rxtx.c: dev->tx_pkt_prepare = i40e_prep_pkts;
> drivers/net/i40e/i40e_rxtx.c: eth_tx_burst_t pkt_burst = dev->tx_pkt_burst;
> drivers/net/i40e/i40e_vf_representor.c: ethdev->tx_pkt_burst =
> i40e_vf_representor_tx_burst;
>
>
> --
> David Marchand
Hi David,
Yes, if agreed to set the same prepare function for all Tx path, can leave the
setting in one place.
