> -----Original Message-----
> From: Roopa Prabhu [mailto:ro...@cumulusnetworks.com]
> Sent: Wednesday, August 10, 2016 9:09 AM
> To: Jiri Pirko <j...@resnulli.us>
> Cc: netdev@vger.kernel.org; da...@davemloft.net; Nogah Frankel
> <nog...@mellanox.com>; Ido Schimmel <ido...@mellanox.com>; Elad
> Raz <el...@mellanox.com>; Yotam Gigi <yot...@mellanox.com>; Or
> Gerlitz <ogerl...@mellanox.com>; niko...@cumulusnetworks.com;
> linvi...@tuxdriver.com; tg...@suug.ch; go...@cumulusnetworks.com;
> sfel...@gmail.com; s...@queasysnail.net; Eran Ben Elisha
> <era...@mellanox.com>; a...@plumgrid.com; eduma...@google.com;
> han...@stressinduktion.org; f.faine...@gmail.com;
> d...@cumulusnetworks.com
> Subject: Re: [patch net-next v6 2/3] net: core: add SW stats to if_stats_msg
>
> On 8/9/16, 2:25 PM, Jiri Pirko wrote:
> > From: Nogah Frankel <nog...@mellanox.com>
> >
> > Add a nested attribute of SW stats to if_stats_msg
> > under IFLA_STATS_LINK_SW_64.
> >
> > Signed-off-by: Nogah Frankel <nog...@mellanox.com>
> > Reviewed-by: Ido Schimmel <ido...@mellanox.com>
> > Signed-off-by: Jiri Pirko <j...@mellanox.com>
> > ---
> > include/uapi/linux/if_link.h | 1 +
> > net/core/rtnetlink.c | 21 +++++++++++++++++++++
> > 2 files changed, 22 insertions(+)
> >
> > diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
> > index a1b5202..1c9b808 100644
> > --- a/include/uapi/linux/if_link.h
> > +++ b/include/uapi/linux/if_link.h
> > @@ -825,6 +825,7 @@ enum {
> > IFLA_STATS_LINK_64,
> > IFLA_STATS_LINK_XSTATS,
> > IFLA_STATS_LINK_XSTATS_SLAVE,
> > + IFLA_STATS_LINK_SW_64,
>
> sorry, don't mean to drag this discussion forever...but...
>
> IIRC on the switchdev call, I thought we had agreed to just put these kind of
> breakdown
> stats in one more layer of nesting.. which can be extended for everybody.
>
> IFLA_STATS_LINK_DRIVER_XSTATS (or some other name) [
> IFLA_STATS_LINK_SW_64 (struct rtnl_link_stats64) <----
> you get
> the well defined struct here as you wanted.
> IFLA_STATS_LINK_HW_ACL_DROPS /* u64 */ <----- we can
> keep extending this for other stats people want.
>
> /* just keeps it extensible */
> ]
>
> because in addition to all other reasons I have mentioned before,
> technically IFLA_STATS_LINK_64 (top-level aggregate stats)
> are also software only stats for say most logical devices etc.
>
>
> and instead of adding one ndo for your software only stats now and then
> again for other ethtool
> like hw stats from all drivers, it could also be like the below:
>
> new ndo_get_hw_stats
>
> IFLA_STATS_LINK_HW_XSTATS (or some other name) [
> IFLA_STATS_LINK_CPU_64 (struct rtnl_link_stats64) <----
> you
> get the well defined struct here as you wanted.
> IFLA_STATS_LINK_HW_ACL_DROPS /* u64 */ <-----
> we can
> keep extending this for other stats people want.
> /* just keeps it extensible */
> ]
>
> It gets you what you want and keeps the api extensible IMO. your call.
>
I don't think extra nesting is a good idea because when we are called for
IFLA_STATS_LINK_DRIVER_XSTATS we can't distinguish between subtypes of it.
So for each driver stats we are going to need different XSTATS types anyway.
We shouldn't return all the stats a driver can provide when we are asked for
one.
HW_ACL_DROPS shouldn't be queried when user want SW stats nor the other
way around.
(And I think that stats exposed here should be well defined so they could
be exposed to ifstat. The place for not well define stats is in ethtool)
> > __IFLA_STATS_MAX,
> > };
> >
> > diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
> > index 189cc78..910f802 100644
> > --- a/net/core/rtnetlink.c
> > +++ b/net/core/rtnetlink.c
> > @@ -3583,6 +3583,21 @@ static int rtnl_fill_statsinfo(struct sk_buff
> *skb, struct net_device *dev,
> > dev_get_stats(dev, sp);
> > }
> >
> > + if (stats_attr_valid(filter_mask, IFLA_STATS_LINK_SW_64,
> *idxattr)) {
> > + if (dev_have_sw_stats(dev)) {
> > + struct rtnl_link_stats64 *sp;
> > +
> > + attr = nla_reserve_64bit(skb,
> IFLA_STATS_LINK_SW_64,
> > + sizeof(struct
> rtnl_link_stats64),
> > + IFLA_STATS_UNSPEC);
> > + if (!attr)
> > + goto nla_put_failure;
> > +
> > + sp = nla_data(attr);
> > + dev_get_sw_stats(dev, sp);
> > + }
> > + }
> > +
> > if (stats_attr_valid(filter_mask, IFLA_STATS_LINK_XSTATS,
> *idxattr)) {
> > const struct rtnl_link_ops *ops = dev->rtnl_link_ops;
> >
> > @@ -3644,6 +3659,7 @@ nla_put_failure:
> >
> > static const struct nla_policy ifla_stats_policy[IFLA_STATS_MAX + 1] = {
> > [IFLA_STATS_LINK_64] = { .len = sizeof(struct rtnl_link_stats64) },
> > + [IFLA_STATS_LINK_SW_64] = { .len = sizeof(struct
> rtnl_link_stats64) },
> > };
> >
> > static size_t if_nlmsg_stats_size(const struct net_device *dev,
> > @@ -3685,6 +3701,11 @@ static size_t if_nlmsg_stats_size(const struct
> net_device *dev,
> > }
> > }
> >
> > + if (stats_attr_valid(filter_mask, IFLA_STATS_LINK_SW_64, 0)) {
> > + if (dev_have_sw_stats(dev))
> > + size += nla_total_size_64bit(sizeof(struct
> rtnl_link_stats64));
> > + }
> > +
> > return size;
> > }
> >
