Subject: Re: [PATCH net-next V6 7/8] net/dcb: Add an optional max rate attribute

From: John Fastabend <[email-masked]>
Date: Wed, 04 Apr 2012 17:23:58 -0700

On 4/4/2012 3:58 AM, Amir Vadai wrote:
> Although not specified in 8021Qaz spec, it could be useful to enable drivers
> whose HW supports setting a rate limit for an ETS TC. This patch adds this
> optional attribute to DCB netlink. To use it, drivers should implement and
> register the callbacks ieee_setmaxrate and ieee_getmaxrate. The units are 64
> bits long and specified in Kbps to enable usage over both slow and very fast
> networks.
> 
> Signed-off-by: Amir Vadai <[email-masked]>
> ---

Or, Amir,

Two more comments inline really just minor nit picks but if your going
to roll new patch mind as well. I'll ack a patch with these changes.

>  include/linux/dcbnl.h |    5 +++++
>  include/net/dcbnl.h   |    2 ++
>  net/dcb/dcbnl.c       |   21 +++++++++++++++++++++
>  3 files changed, 28 insertions(+), 0 deletions(-)
> 
> diff --git a/include/linux/dcbnl.h b/include/linux/dcbnl.h
> index 65a2562..ec8e372 100644
> --- a/include/linux/dcbnl.h
> +++ b/include/linux/dcbnl.h
> @@ -67,6 +67,10 @@ struct ieee_ets {
>  	__u8	reco_prio_tc[IEEE_8021QAZ_MAX_TCS];
>  };
>  

annotate ieee_maxrate so implementers use it correctly per previous note.

> +struct ieee_maxrate {
> +	__u64	tc_maxrate[IEEE_8021QAZ_MAX_TCS];
> +};
> +
>  /* This structure contains the IEEE 802.1Qaz PFC managed object
>   *
>   * @pfc_cap: Indicates the number of traffic classes on the local device
> @@ -321,6 +325,7 @@ enum ieee_attrs {
>  	DCB_ATTR_IEEE_PEER_ETS,
>  	DCB_ATTR_IEEE_PEER_PFC,
>  	DCB_ATTR_IEEE_PEER_APP,
> +	DCB_ATTR_IEEE_MAXRATE,
>  	__DCB_ATTR_IEEE_MAX
>  };
>  #define DCB_ATTR_IEEE_MAX (__DCB_ATTR_IEEE_MAX - 1)
> diff --git a/include/net/dcbnl.h b/include/net/dcbnl.h
> index f55c980..fc5d5dc 100644
> --- a/include/net/dcbnl.h
> +++ b/include/net/dcbnl.h
> @@ -48,6 +48,8 @@ struct dcbnl_rtnl_ops {
>  	/* IEEE 802.1Qaz std */
>  	int (*ieee_getets) (struct net_device *, struct ieee_ets *);
>  	int (*ieee_setets) (struct net_device *, struct ieee_ets *);
> +	int (*ieee_getmaxrate) (struct net_device *, struct ieee_maxrate *);
> +	int (*ieee_setmaxrate) (struct net_device *, struct ieee_maxrate *);
>  	int (*ieee_getpfc) (struct net_device *, struct ieee_pfc *);
>  	int (*ieee_setpfc) (struct net_device *, struct ieee_pfc *);
>  	int (*ieee_getapp) (struct net_device *, struct dcb_app *);
> diff --git a/net/dcb/dcbnl.c b/net/dcb/dcbnl.c
> index 36f37af..d3df048 100644
> --- a/net/dcb/dcbnl.c
> +++ b/net/dcb/dcbnl.c
> @@ -178,6 +178,8 @@ static const struct nla_policy dcbnl_ieee_policy[DCB_ATTR_IEEE_MAX + 1] = {
>  	[DCB_ATTR_IEEE_ETS]	    = {.len = sizeof(struct ieee_ets)},
>  	[DCB_ATTR_IEEE_PFC]	    = {.len = sizeof(struct ieee_pfc)},
>  	[DCB_ATTR_IEEE_APP_TABLE]   = {.type = NLA_NESTED},
> +	[DCB_ATTR_IEEE_MAXRATE]   = {.len = sizeof(struct ieee_maxrate)},
> +

spurious newline remove it

>  };
>  
>  static const struct nla_policy dcbnl_ieee_app[DCB_ATTR_IEEE_APP_MAX + 1] = {
> @@ -1246,6 +1248,17 @@ static int dcbnl_ieee_fill(struct sk_buff *skb, struct net_device *netdev)
>  			goto nla_put_failure;
>  	}
>  
> +	if (ops->ieee_getmaxrate) {
> +		struct ieee_maxrate maxrate;
> +		err = ops->ieee_getmaxrate(netdev, &maxrate);
> +		if (!err) {
> +			err = nla_put(skb, DCB_ATTR_IEEE_MAXRATE,
> +					sizeof(maxrate), &maxrate);

align sizeof with skb

Thanks,
John