On 9/5/16, 10:18 AM, Jiri Pirko wrote: > From: Jiri Pirko <j...@mellanox.com> > > The problem we try to handle is about offloaded forwarded packets > which are not seen by kernel. Let me try to draw it: > > port1 port2 (HW stats are counted here) > \ / > \ / > \ / > --(A)---- ASIC --(B)-- > | > (C) > | > CPU (SW stats are counted here) > > > Now we have couple of flows for TX and RX (direction does not matter here): > > 1) port1->A->ASIC->C->CPU > > For this flow, HW and SW stats are equal. > > 2) port1->A->ASIC->C->CPU->C->ASIC->B->port2 > > For this flow, HW and SW stats are equal. > > 3) port1->A->ASIC->B->port2 > > For this flow, SW stats are 0. > > The purpose of this patchset is to provide facility for user to > find out the difference between flows 1+2 and 3. In other words, user > will be able to see the statistics for the slow-path (through kernel). > > Also note that HW stats are what someone calls "accumulated" stats. > Every packet counted by SW is also counted by HW. Not the other way around. > > As a default the accumulated stats (HW) will be exposed to user > so the userspace apps can react properly. > > This patchset add the SW stats (flows 1+2) under offload related stats, so > in the future we can expose other offload related stat in a similar way. > > --- > Acked-by: Roopa Prabhu <ro...@cumulusnetworks.com> few questions on the two ndo's on specific patches, but, the user api LGTM.
thanks jiri and nogah.
