On Tue, 4 Feb 2025 17:26:43 +0000 Amit Cohen wrote: > > > You're right, most of packets should be handled by HW, XDP is > > > mainly useful for telemetry. > > > > Why skb path is not enough? > > We get better packet rates using XDP, this can be useful to redirect > packets to a server for analysis for example. TBH I also feel a little ambivalent about adding advanced software features to mlxsw. You have a dummy device off which you hang the NAPIs, the page pools, and now the RXQ objects. That already works poorly with our APIs. How are you going to handle the XDP side? Program per port, I hope? But the basic fact remains that only fallback traffic goes thru the XDP program which is not the normal Linux model, routing is after XDP. On one hand it'd be great if upstream switch drivers could benefit from the advanced features. On the other the HW is clearly not capable of delivering in line with how NICs work, so we're signing up for a stream of corner cases, bugs and incompatibility. Dunno.
