Re: [dpdk-dev] [PATCH] net/iavf: fix adding multicast MAC address

["Xing, Beilei" <beilei.xing@intel.com>]

> -----Original Message-----
> From: Sun, GuinanX <guinanx.sun@intel.com>
> Sent: Thursday, October 15, 2020 1:57 PM
> To: Xing, Beilei <beilei.xing@intel.com>; Peng, Yuan <yuan.peng@intel.com>;
> dev@dpdk.org
> Cc: Wu, Jingjing <jingjing.wu@intel.com>; Zhang, Qi Z <qi.z.zhang@intel.com>
> Subject: RE: [dpdk-dev] [PATCH] net/iavf: fix adding multicast MAC address
> 
> Hi beilei
> 
> > -----Original Message-----
> > From: Xing, Beilei <beilei.xing@intel.com>
> > Sent: Thursday, October 15, 2020 1:37 PM
> > To: Peng, Yuan <yuan.peng@intel.com>; Sun, GuinanX
> > <guinanx.sun@intel.com>; dev@dpdk.org
> > Cc: Wu, Jingjing <jingjing.wu@intel.com>; Zhang, Qi Z
> > <qi.z.zhang@intel.com>; Sun, GuinanX <guinanx.sun@intel.com>
> > Subject: RE: [dpdk-dev] [PATCH] net/iavf: fix adding multicast MAC
> > address
> >
> >
> >
> > > -----Original Message-----
> > > From: Peng, Yuan <yuan.peng@intel.com>
> > > Sent: Thursday, October 15, 2020 1:14 PM
> > > To: Sun, GuinanX <guinanx.sun@intel.com>; dev@dpdk.org
> > > Cc: Xing, Beilei <beilei.xing@intel.com>; Wu, Jingjing
> > > <jingjing.wu@intel.com>; Zhang, Qi Z <qi.z.zhang@intel.com>; Sun,
> > > GuinanX <guinanx.sun@intel.com>
> > > Subject: RE: [dpdk-dev] [PATCH] net/iavf: fix adding multicast MAC
> > > address
> > >
> > > Test-by Peng, Yuan <yuan.peng@intel.com>
> > >
> > >
> > > -----Original Message-----
> > > From: dev <dev-bounces@dpdk.org> On Behalf Of Guinan Sun
> > > Sent: Thursday, October 15, 2020 10:02 AM
> > > To: dev@dpdk.org
> > > Cc: Xing, Beilei <beilei.xing@intel.com>; Wu, Jingjing
> > > <jingjing.wu@intel.com>; Zhang, Qi Z <qi.z.zhang@intel.com>; Sun,
> > > GuinanX <guinanx.sun@intel.com>
> > > Subject: [dpdk-dev] [PATCH] net/iavf: fix adding multicast MAC
> > > address
> > >
> > > When the multicast address is added, it will flush previous
> > > addresses first, and then add new ones.
> > > So when adding an address that exceeds the upper limit causes a
> > > failure, you need to add the previous address list back. This patch
> > > fixes the
> > issue.
> > >
> > > Fixes: 05e4c3aff35f ("net/iavf: support multicast configuration")
> > >
> > > Signed-off-by: Guinan Sun <guinanx.sun@intel.com>
> > > ---
> > >  drivers/net/iavf/iavf_ethdev.c | 30 ++++++++++++++++++++++--------
> > > drivers/net/iavf/iavf_vchnl.c  |  3 ---
> > >  2 files changed, 22 insertions(+), 11 deletions(-)
> > >
> > > diff --git a/drivers/net/iavf/iavf_ethdev.c
> > > b/drivers/net/iavf/iavf_ethdev.c index e68e3bc71..042edadd9 100644
> > > --- a/drivers/net/iavf/iavf_ethdev.c
> > > +++ b/drivers/net/iavf/iavf_ethdev.c
> > > @@ -164,7 +164,14 @@ iavf_set_mc_addr_list(struct rte_eth_dev *dev,
> > > struct iavf_info *vf = IAVF_DEV_PRIVATE_TO_VF(dev->data-
> > > >dev_private);
> > >  struct iavf_adapter *adapter =
> > >  IAVF_DEV_PRIVATE_TO_ADAPTER(dev->data->dev_private);
> > > -int err;
> > > +int err, temp_err;
> > > +
> > > +if (mc_addrs_num > IAVF_NUM_MACADDR_MAX) { PMD_DRV_LOG(ERR,
> > > +    "can't add more than a limited number (%u) of
> > > addresses.",
> > > +    (uint32_t)IAVF_NUM_MACADDR_MAX); return -EINVAL; }
> > >
> > >  /* flush previous addresses */
> > >  err = iavf_add_del_mc_addr_list(adapter, vf->mc_addrs, vf-
> > > >mc_addrs_num, @@ -172,17 +179,24 @@ iavf_set_mc_addr_list(struct
> > > rte_eth_dev *dev,
> > >  if (err)
> > >  return err;
> > >
> > > -vf->mc_addrs_num = 0;
> > > -
> > >  /* add new ones */
> > >  err = iavf_add_del_mc_addr_list(adapter, mc_addrs, mc_addrs_num,
> > > true); -if (err) -return err;
> > >
> > > -vf->mc_addrs_num = mc_addrs_num;
> > > -memcpy(vf->mc_addrs, mc_addrs, mc_addrs_num * sizeof(*mc_addrs));
> > > +if (err) {
> > > +/* When adding new addresses fail, need to add the
> > > + * previous addresses back.
> > > + */
> > > +temp_err = iavf_add_del_mc_addr_list(adapter, vf->mc_addrs,
> > > +     vf->mc_addrs_num, true);
> >
> > Can we reuse err here?
> 
> This err cannot be reused.
> 
> When performing mac address addition, the testpmd side will first add the
> mac address to mac_pool.
> When the driver layer returns that it failed to add an address, the tespmd layer
> will delete the failed address from mac_pool.
> 
> If err is reused, the successful result of executing the add back address will
> overwrite the previous err, causing problems with the address stored in
> mac_pool on the testpmd side.
> 

Yes, I missed return err in the end of the function.
Little comments, can we use 'ret' which is more common to indicate return value?

> >
> > > +if (temp_err)
> > > +return temp_err;
> > > +} else {
> > > +vf->mc_addrs_num = mc_addrs_num;
> > > +memcpy(vf->mc_addrs,
> > > +       mc_addrs, mc_addrs_num * sizeof(*mc_addrs)); }
> > >
> > > -return 0;
> > > +return err;
> > >  }
> > >
> > >  static int
> > > diff --git a/drivers/net/iavf/iavf_vchnl.c
> > > b/drivers/net/iavf/iavf_vchnl.c index
> > > db0b76876..a2295f879 100644
> > > --- a/drivers/net/iavf/iavf_vchnl.c
> > > +++ b/drivers/net/iavf/iavf_vchnl.c
> > > @@ -1107,9 +1107,6 @@ iavf_add_del_mc_addr_list(struct iavf_adapter
> > > *adapter,  if (mc_addrs == NULL || mc_addrs_num == 0)  return 0;
> > >
> > > -if (mc_addrs_num > IAVF_NUM_MACADDR_MAX) -return -EINVAL;
> > > -
> > >  list = (struct virtchnl_ether_addr_list *)cmd_buffer;  list->vsi_id
> > > =
> > > vf->vsi_res->vsi_id;  list->num_elements = mc_addrs_num;
> > > --
> > > 2.13.6
> >
>