Commit Graph

2 Commits

Author SHA1 Message Date
Eric Leblond b259c2ffd9 samples/bpf: use bpf_set_link_xdp_fd
Use bpf_set_link_xdp_fd instead of set_link_xdp_fd to remove some
code duplication and benefit of netlink ext ack errors message.

Signed-off-by: Eric Leblond <eric@regit.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-02-02 17:53:48 -08:00
Jesper Dangaard Brouer 0fca931a6f samples/bpf: program demonstrating access to xdp_rxq_info
This sample program can be used for monitoring and reporting how many
packets per sec (pps) are received per NIC RX queue index and which
CPU processed the packet. In itself it is a useful tool for quickly
identifying RSS imbalance issues, see below.

The default XDP action is XDP_PASS in-order to provide a monitor
mode. For benchmarking purposes it is possible to specify other XDP
actions on the cmdline --action.

Output below shows an imbalance RSS case where most RXQ's deliver to
CPU-0 while CPU-2 only get packets from a single RXQ.  Looking at
things from a CPU level the two CPUs are processing approx the same
amount, BUT looking at the rx_queue_index levels it is clear that
RXQ-2 receive much better service, than other RXQs which all share CPU-0.

Running XDP on dev:i40e1 (ifindex:3) action:XDP_PASS
XDP stats       CPU     pps         issue-pps
XDP-RX CPU      0       900,473     0
XDP-RX CPU      2       906,921     0
XDP-RX CPU      total   1,807,395

RXQ stats       RXQ:CPU pps         issue-pps
rx_queue_index    0:0   180,098     0
rx_queue_index    0:sum 180,098
rx_queue_index    1:0   180,098     0
rx_queue_index    1:sum 180,098
rx_queue_index    2:2   906,921     0
rx_queue_index    2:sum 906,921
rx_queue_index    3:0   180,098     0
rx_queue_index    3:sum 180,098
rx_queue_index    4:0   180,082     0
rx_queue_index    4:sum 180,082
rx_queue_index    5:0   180,093     0
rx_queue_index    5:sum 180,093

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-05 15:21:22 -08:00