This series introduces tracing infrastructure for AF_XDP sockets (xsks). A trace event 'xsk_packet_drop' is created which can be enabled by toggling /sys/kernel/debug/tracing/events/xsk/xsk_packet_drop/enable When enabled and packets are dropped in the kernel, traces are generated which describe the reason for the packet drop as well as the netdev and qid information of the xsk which encountered the drop. Example traces: 507.588563: xsk_packet_drop: netdev: eth0 qid 0 reason: rxq full 507.588567: xsk_packet_drop: netdev: eth0 qid 0 reason: packet too big 507.588568: xsk_packet_drop: netdev: eth0 qid 0 reason: fq empty The event can also be monitored using perf: perf stat -a -e xsk:xsk_packet_drop Three selftests are added which each ensure the appropriate traces are generated for the following scenarios: * rx queue full * packet too big * fill queue empty Ciara Loftus (6): xsk: add tracepoints for packet drops selftests/bpf: restructure setting the packet count selftests/bpf: add framework for xsk selftests selftests/bpf: XSK_TRACE_DROP_RXQ_FULL test selftests/bpf: XSK_TRACE_DROP_PKT_TOO_BIG test selftests/bpf: XSK_TRACE_DROP_FQ_EMPTY test MAINTAINERS | 1 + include/linux/bpf_trace.h | 1 + include/trace/events/xsk.h | 45 +++++ include/uapi/linux/if_xdp.h | 8 + kernel/bpf/core.c | 1 + net/xdp/xsk.c | 5 + net/xdp/xsk_buff_pool.c | 8 +- tools/include/uapi/linux/if_xdp.h | 8 + tools/testing/selftests/bpf/test_xsk.sh | 90 +++++++++- tools/testing/selftests/bpf/xdpxceiver.c | 186 +++++++++++++++++++-- tools/testing/selftests/bpf/xdpxceiver.h | 10 ++ tools/testing/selftests/bpf/xsk_prereqs.sh | 3 +- 12 files changed, 344 insertions(+), 22 deletions(-) create mode 100644 include/trace/events/xsk.h -- 2.17.1
