[PATCH v2 01/10] net/ngbe: fix Rx buffer size in configure register

[Jiawen Wu]

On Wednesday, February 15, 2023 5:36 PM, Ferruh Yigit wrote:
> On 2/14/2023 9:55 AM, Ferruh Yigit wrote:
> > On 2/14/2023 8:15 AM, Jiawen Wu wrote:
> >> On Thursday, February 9, 2023 5:00 PM, Jiawen Wu wrote:
> >>> On Wednesday, February 8, 2023 6:28 PM, Ferruh Yigit wrote:
> >>>> On 2/2/2023 9:21 AM, Jiawen Wu wrote:
> >>>>> When buffer size is less than 1K, round down makes it 0, which is
> >>>>> an error value.
> >>>>>
> >>>>> Fixes: 62fc35e63d0e ("net/ngbe: support Rx queue start/stop")
> >>>>> Cc: stable at dpdk.org
> >>>>>
> >>>>> Signed-off-by: Jiawen Wu <jiawenwu at trustnetic.com>
> >>>>> ---
> >>>>>  drivers/net/ngbe/ngbe_rxtx.c | 5 ++++-
> >>>>>  1 file changed, 4 insertions(+), 1 deletion(-)
> >>>>>
> >>>>> diff --git a/drivers/net/ngbe/ngbe_rxtx.c
> >>>>> b/drivers/net/ngbe/ngbe_rxtx.c index 9fd24fa444..9a646cb6a7 100644
> >>>>> --- a/drivers/net/ngbe/ngbe_rxtx.c
> >>>>> +++ b/drivers/net/ngbe/ngbe_rxtx.c
> >>>>> @@ -2944,7 +2944,10 @@ ngbe_dev_rx_init(struct rte_eth_dev *dev)
> >>>>>  		 */
> >>>>>  		buf_size = (uint16_t)(rte_pktmbuf_data_room_size(rxq->mb_pool) -
> >>>>>  			RTE_PKTMBUF_HEADROOM);
> >>>>> -		buf_size = ROUND_DOWN(buf_size, 0x1 << 10);
> >>>>> +		if (buf_size < 1024)
> >>>>> +			buf_size = ROUND_UP(buf_size, 0x1 << 10);
> >>>>
> >>>> Back to original problem statement in previous version, can't this
> >>>> cause HW to receive packets exceeding the buffer size?
> >>>>
> >>>> If HW accepts buffer size in multiple of 1K, does this mean any
> >>>> buffer size less than 1K is an error condition for this HW?
> >>>>
> >>>
> >>> After rechecking the code, the minimum buffer size is limited to 1K
> >>> by the txgbe/ngbe [1].
> >>> I think v1 patch for txgbe is enough.
> >>>
> >>> [1]
> >>> static int
> >>> txgbe_dev_info_get(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info) {
> >>> 	struct rte_pci_device *pci_dev = RTE_ETH_DEV_TO_PCI(dev);
> >>> 	struct txgbe_hw *hw = TXGBE_DEV_HW(dev);
> >>>
> >>> 	dev_info->min_rx_bufsize = 1024;
> >>>
> >>>
> >>>>> +		else
> >>>>> +			buf_size = ROUND_DOWN(buf_size, 0x1 << 10);
> >>>>>  		srrctl |= NGBE_RXCFG_PKTLEN(buf_size);
> >>>>>
> >>>>>  		wr32(hw, NGBE_RXCFG(rxq->reg_idx), srrctl);
> >>>>
> >>>>
> >>>
> >>
> >> Hi Ferruh,
> >>
> >> Is my proposal feasible or do I need to send v3 patch for it?
> >>
> >>
> >
> > Sorry Jiawen, I missed your response.
> >
> > Yes, you are right, 'dev_info->min_rx_bufsize' prevents user to set
> > buffer size less than 1K, so change in V1 is good.
> >
> > There were some other changes too, instead of getting this patch from
> > v1, can you please send a new version with latest updates?
> 
> We can drop 1/10 and you have sent a v3 for 2/10, right?
> 
> 

Yes.