2016-02-26 04:31, Wang, Xiao W: > From: Richardson, Bruce > > On Thu, Feb 25, 2016 at 03:45:45PM +0000, Chen, Jing D wrote: > > > From: Richardson, Bruce > > > > On Thu, Feb 25, 2016 at 10:04:02AM +0000, Chen, Jing D wrote: > > > > > This feature is trying to use FTAG (a unique tech in fm10k) > > > > > instead of mac/vlan to forward packets. App need a way to tell PMD > > > > > driver that which forwarding style it would like to use. > > > > > > > > Why not just specify this in the port configuration at setup time? > > > > > > > > > > Please educate me. I think the port configuration flags are also > > > common to all PMD Drivers. Is it possible to add a flag like > > > "RTE_USE_FTAG" > > and pass to PMD driver? > > > > > They are. > > For something PMD specific, like FTAG, it's always a challenge, and I don't > > know off the top of my head if there is a simple option. However, given the > > choice between an mbuf flag and a port config flag, I'd always choose the > > former. > > Other alternatives would be to have a fm10k specific API in the fm10k driver > > alone. > > > > I'll let Thomas as ethdev maintainer comment if he has other suggestions as > > to > > how to handle this case. I suspect this won't be the first device-specific > > piece of > > functionality we need to deal with. > > > > /Bruce > > Whatever method we choose, we have to find a way for the user to express his > need > for FTAG, it maybe a build time config option, or a port config flag (no such > flag now), > or a fast path flag in mbuf (no such flag now) etc. For the customer Topsec's > use case, > they use FTAG for all the TX packets, so all the above methods (per build > config, per > port config, per mbuf config) can meet their need. Since the pmd frame work > is for > common, it's hard to add new fields only for one specific NIC, so I add a > build time > config and make an introduction in the doc. > > Thanks for the discussion, Thomas, do you have any suggestions?
I don't understand why you say this feature is specific to fm10k. Can we imagine another NIC having this capability? I think it must be an port configuration, as Bruce suggested. What about a field in struct rte_eth_conf?
