Hi Ferruh,
> -----Original Message----- > From: Yigit, Ferruh > Sent: Friday, April 28, 2017 8:38 PM > To: Wu, Jingjing; Lu, Wenzhuo; dev@dpdk.org > Subject: Re: [dpdk-dev] [PATCH] net/i40e: consider QinQ when setting MTU > > On 4/28/2017 9:27 AM, Wu, Jingjing wrote: > > > > > >> -----Original Message----- > >> From: dev [mailto:dev-boun...@dpdk.org] On Behalf Of Ferruh Yigit > >> Sent: Friday, April 28, 2017 1:55 PM > >> To: Lu, Wenzhuo <wenzhuo...@intel.com>; dev@dpdk.org > >> Subject: Re: [dpdk-dev] [PATCH] net/i40e: consider QinQ when setting > >> MTU > >> > >> On 4/28/2017 2:55 AM, Wenzhuo Lu wrote: > >>> When counting max packet length from MTU, count VLAN tag length > >>> twice for QinQ packets. > >>> > >>> Signed-off-by: Wenzhuo Lu <wenzhuo...@intel.com> > >>> --- > >>> drivers/net/i40e/i40e_ethdev.c | 2 +- > >>> drivers/net/i40e/i40e_ethdev_vf.c | 2 +- > >>> 2 files changed, 2 insertions(+), 2 deletions(-) > >>> > >>> diff --git a/drivers/net/i40e/i40e_ethdev.c > >>> b/drivers/net/i40e/i40e_ethdev.c index 3fa25dc..74041ae 100644 > >>> --- a/drivers/net/i40e/i40e_ethdev.c > >>> +++ b/drivers/net/i40e/i40e_ethdev.c > >>> @@ -10593,7 +10593,7 @@ static void > i40e_set_default_mac_addr(struct > >> rte_eth_dev *dev, > >>> struct i40e_pf *pf = I40E_DEV_PRIVATE_TO_PF(dev->data- > >>> dev_private); > >>> struct rte_eth_dev_data *dev_data = pf->dev_data; > >>> uint32_t frame_size = mtu + ETHER_HDR_LEN > >>> - + ETHER_CRC_LEN + I40E_VLAN_TAG_SIZE; > >>> + + ETHER_CRC_LEN + I40E_VLAN_TAG_SIZE * 2; > >> > >> Hi Wenzhuo, > >> > >> Shouldn't we check if QinQ enabled before taking size account? > > > > Hi, Ferruh > > > > Checking QinQ enabled here makes no sense, because we don't know If > > the packets is carry single vlan or double vlan. > > What do you think commenting code to say "I40E_VLAN_TAG_SIZE * 2" is for > QinQ? > > It is not obvious and in the feature somebody not thinking about QinQ use > case may miss this, and do something wrong, even can fix this J Thanks for your suggestion. I'll send a V2 to add the comments. > > > > > Acked-by: Jingjing Wu <jingjing...@intel.com> > >
