Fri, May 13, 2016 at 12:23:13AM CEST, f.faine...@gmail.com wrote: >2016-05-12 14:10 GMT-07:00 Roopa Prabhu <ro...@cumulusnetworks.com>: >> On 5/12/16, 4:48 AM, Jiri Pirko wrote: >>> From: Nogah Frankel <nog...@mellanox.com> >>> >>> Till now we had a ndo statistics function that returned SW statistics. >>> We want to change the "basic" statistics to return HW statistics if >>> available. >>> In this case we need to expose a new ndo to return the SW statistics. >>> Add a new ndo declaration to get SW statistics >>> Add a function that gets SW statistics if a competible ndo exist >>> >>> Signed-off-by: Nogah Frankel <nog...@mellanox.com> >>> Reviewed-by: Ido Schimmel <ido...@mellanox.com> >>> Signed-off-by: Jiri Pirko <j...@mellanox.com> >>> --- >>> >> To me netdev stats is combined 'SW + HW' stats for that netdev. >> ndo_get_stats64 callback into the drivers does the magic of adding HW stats >> to SW (netdev) stats and returning (see enic_get_stats). HW stats is >> available for netdevs >> that are offloaded or are backed by hardware. SW stats is the stats that the >> driver maintains >> (logical or physical). HW stats is queried and added to the SW stats. >> In fact, we represent all our offloaded netdev stats following this model. >> This fits well for logical devices like vlan/bond/vxlan which are hardware >> offloaded too. > >Agreed, if you take a look at what the DSA slave network devices do in >net/dsa/slave.c they basically overload the switch-mainainted >statistics with some per-port net_device software stats. We would >probably want to do the same thing
net/dsa/slave.c does not define ndo_get_stats*. I don't follow. > >> >> There is HW extended stats which today are represented by ethtool >> and I had an example of a new nested attribute like >> IFLA_STATS_LINK_HW_EXTENDED >> to provide ethtool like extensible stats. If people want pure hardware >> stats, they >> get it via this. In which case I am not seeing the point in adding a new ndo >> and a new >> stats attribute just for this. If you are looking for pure hardware stats, >> any reason we cant >> just use the IFLA_STATS_LINK_HW_EXTENDED and add ethtool like hw stats ?. >> This will be one place to look for all hardware stats and will be extensible >> too. > >Agreed, worste case, you format your statistics such that they reflect >they come from the HW (e.g: hw_TxOctets...) >-- >Florian
