Hi Simon, Thanks for the feedback.
Please find my comments inline. Best Regards Chandra On Tue, Jun 2, 2020 at 2:20 PM Simon Horman <[email protected]> wrote: > On Fri, May 29, 2020 at 01:45:16PM -0700, Ben Pfaff wrote: > > This seems like something for Simon to look at. > > > > On Fri, May 29, 2020 at 04:56:11PM +0530, K Chandra wrote: > > > OVS-TC offload sends only fields that are not completely masked out to > the > > > TC kernel module. Some of the hardware we work with requires all fields > > > extracted from the packet along with the mask to be sent to the driver. > > > Hardware may optimise tables based on entire fields of packet and mask > of > > > field, even though certain fields are masked out. OVS when offloading > to > > > ovs kernel datapath sends the entire key along with the mask. Proposal > > > requests for similar behaviour in ovs-vswitchd in case of tc-offload. > While > > > constructing netlink messages, ovs-vswitchd is removing completely > masked > > > out fields. Sending additional masked fields should not impact existing > > > drivers. TC internally uses dissectors to extract non masked fields, > so it > > > should not impact existing drivers in tc. > > > > > > Example: > > > > > > ovs-rule:ovs-ofctl add-flow br0 \ > > > > > > "table=0, dl_dst=00:a1:45:23:23:11/ff:ff:ff:ff:ff:ff, actions=1" > > > > > > If we have above rule in ovs and an icmp packet matching destination > MAC > > > 00:a1:45:23:23:11 arrives, ovs prepares the key and mask with all > relevant > > > fields. When sending to TC it removes fields which are completely > masked > > > out. In this case ethertype, ip-proto and dst_mac fields are sent as > part > > > of netlink message to tc. > > Hi K Chandra, > > I agree that this is reasonable from a HW perspective and should not pose > a problem for existing HW offload that does not require this (though > perhaps kernel TC or offlaod driver code may need to be updated). > I agree that changes are required for kernel TC as well. We identified code changes required for kernel TC. We will post the patch to Linux community as well. > > It does seem likely to me that the bulk of this work would likely lie > in modifications to ovs-vswitchd. Are you aware of any existing work in > this area - I am not. > All the changes are in ovs-vswitchd only. Will post a patch to ovs-dev after testing. > > Kind regards, > Simon >
_______________________________________________ discuss mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-discuss
