On Fri, 18 Jun 2021 13:31:06 -0300 "Ethy H. Brito" <ethy.brito@xxxxxxxxxxxx> wrote: > Hi All. > > I've been doing some home work reading the docs and some doubts have raised. > For reference, my environment is > Ubuntu 20.04 > kernel 5.4.0-66 > tc utility, iproute2-ss200127. > > 1) https://xdp-project.net/areas/cpumap.html#cpumap--Create-script-MQ-HTB-silo-setup says that: > "XPS (Transmit Packet Steering) will take precedence over any changes to > skb->queue_mapping. You need to disable *XDP* via mask=00 in files > /sys/class/net/DEV/queues/tx-*/xps_cpus" > > Shouldn't it say I need to disable *XPS* (not XDP) using mask=00?? You are absolutely right it is a typo. Can I ask you to fix that and send a GitHub PR? The file you need to change is: https://github.com/xdp-project/xdp-project/blob/master/areas/cpumap.org > 2) Taking tc_mq_htb_setup_example.sh as reference, how to enable XDP? XDP gets enabled when you load an XDP program. > Since I have to disable XPS, I assume I have to enable something in > replacement, right? No, XPS is just a kernel feature you need to disable, because it conflicts with the TC-BPF program usage of skb->queue_mapping. > How to set that CPU-0 will deal with mq queue 7FFF:1, CPU-1 will deal > with 7FFF:2, and so on? That is the role of the XDP program that redirect into a cpumap, and the key in the cpumap is the CPU number. > 3) Is XDP available in kernel 5.4.0 ? I think so. The real question is what NIC card drivers are you using? > 4) Is XPS a suitable "substitute" for XDP ? XPS and XDP are completely unrelated kernel features. -- Best regards, Jesper Dangaard Brouer MSc.CS, Principal Kernel Engineer at Red Hat LinkedIn: http://www.linkedin.com/in/brouer
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