Re: [PATCH net-next 3/6] net: ethernet: ti: cpsw: add MQPRIO Qdisc offload

[Ivan Khoronzhuk]

On Tue, Jun 12, 2018 at 06:36:58PM +0200, Andrew Lunn wrote:
> On Mon, Jun 11, 2018 at 04:30:44PM +0300, Ivan Khoronzhuk wrote:
> > That's possible to offload vlan to tc priority mapping with
> > assumption sk_prio == L2 prio.
> >
> > Example:
> > $ ethtool -L eth0 rx 1 tx 4
> >
> > $ qdisc replace dev eth0 handle 100: parent root mqprio num_tc 3 \
> > map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 queues 1@0 1@1 2@2 hw 1
> >
> > $ tc -g class show dev eth0
> > +---(100:ffe2) mqprio
> > |    +---(100:3) mqprio
> > |    +---(100:4) mqprio
> > |    
> > +---(100:ffe1) mqprio
> > |    +---(100:2) mqprio
> > |    
> > +---(100:ffe0) mqprio
> >      +---(100:1) mqprio
> >
> > Here, 100:1 is txq0, 100:2 is txq1, 100:3 is txq2, 100:4 is txq3
> > txq0 belongs to tc0, txq1 to tc1, txq2 and txq3 to tc2
> > The offload part only maps L2 prio to classes of traffic, but not
> > to transmit queues, so to direct traffic to traffic class vlan has
> > to be created with appropriate egress map.
> >
> > Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@xxxxxxxxxx>
> > ---
> >  drivers/net/ethernet/ti/cpsw.c | 82 ++++++++++++++++++++++++++++++++++
> >  1 file changed, 82 insertions(+)
> >
> > diff --git a/drivers/net/ethernet/ti/cpsw.c b/drivers/net/ethernet/ti/cpsw.c
> > index 406537d74ec1..fd967d2bce5d 100644
> > --- a/drivers/net/ethernet/ti/cpsw.c
> > +++ b/drivers/net/ethernet/ti/cpsw.c
> > @@ -39,6 +39,7 @@
[...]

> > +static int cpsw_set_tc(struct net_device *ndev, void *type_data)
> > +{
>
> Hi Ivan
>
> Maybe this is not the best of names. What if you add support for
> another TC qdisc? So you have another case in the switch statement
> below?
>
> Maybe call it cpsw_set_mqprio?

Yes, proposed name is more suitable.

--
Regards,
Ivan Khoronzhuk