Re: [PATCH bpf-next v2 2/5] selftests/bpf: xsk selftests - SKB POLL, NOPOLL

[Yonghong Song <yhs@fb.com>]

On 11/20/20 5:00 AM, Weqaar Janjua wrote:
> Adds following tests:
> 
> 1. AF_XDP SKB mode
>     Generic mode XDP is driver independent, used when the driver does
>     not have support for XDP. Works on any netdevice using sockets and
>     generic XDP path. XDP hook from netif_receive_skb().
>     a. nopoll - soft-irq processing
>     b. poll - using poll() syscall
> 
> Signed-off-by: Weqaar Janjua <weqaar.a.janjua@intel.com>
> ---
>   tools/testing/selftests/bpf/Makefile          |   5 +-
>   .../selftests/bpf/test_xsk_prerequisites.sh   |  15 +-
>   .../selftests/bpf/test_xsk_skb_nopoll.sh      |  20 +
>   ..._xsk_framework.sh => test_xsk_skb_poll.sh} |  12 +-
>   tools/testing/selftests/bpf/xdpxceiver.c      | 961 ++++++++++++++++++
>   tools/testing/selftests/bpf/xdpxceiver.h      | 151 +++
>   tools/testing/selftests/bpf/xsk_env.sh        |  17 +
>   7 files changed, 1174 insertions(+), 7 deletions(-)
>   create mode 100755 tools/testing/selftests/bpf/test_xsk_skb_nopoll.sh
>   rename tools/testing/selftests/bpf/{test_xsk_framework.sh => test_xsk_skb_poll.sh} (61%)
>   create mode 100644 tools/testing/selftests/bpf/xdpxceiver.c
>   create mode 100644 tools/testing/selftests/bpf/xdpxceiver.h
> 
> diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
> index 51436db24f32..17af570a32d7 100644
> --- a/tools/testing/selftests/bpf/Makefile
> +++ b/tools/testing/selftests/bpf/Makefile
> @@ -73,7 +73,8 @@ TEST_PROGS := test_kmod.sh \
>   	test_bpftool.sh \
>   	test_bpftool_metadata.sh \
>   	test_xsk_prerequisites.sh \
> -	test_xsk_framework.sh
> +	test_xsk_skb_nopoll.sh \
> +	test_xsk_skb_poll.sh
>   
>   TEST_PROGS_EXTENDED := with_addr.sh \
>   	with_tunnels.sh \
> @@ -84,7 +85,7 @@ TEST_PROGS_EXTENDED := with_addr.sh \
>   # Compile but not part of 'make run_tests'
>   TEST_GEN_PROGS_EXTENDED = test_sock_addr test_skb_cgroup_id_user \
>   	flow_dissector_load test_flow_dissector test_tcp_check_syncookie_user \
> -	test_lirc_mode2_user xdping test_cpp runqslower bench
> +	test_lirc_mode2_user xdping test_cpp runqslower bench xdpxceiver
>   
>   TEST_CUSTOM_PROGS = urandom_read
>   
> diff --git a/tools/testing/selftests/bpf/test_xsk_prerequisites.sh b/tools/testing/selftests/bpf/test_xsk_prerequisites.sh
> index 00bfcf53127c..a9ce8887dffc 100755
> --- a/tools/testing/selftests/bpf/test_xsk_prerequisites.sh
> +++ b/tools/testing/selftests/bpf/test_xsk_prerequisites.sh
> @@ -8,8 +8,17 @@
>   #
>   # Topology:
>   # ---------
> -#      -----------           -----------
> -#      |  xskX   | --------- |  xskY   |
> +#                 -----------
> +#               _ | Process | _
> +#              /  -----------  \
> +#             /        |        \
> +#            /         |         \
> +#      -----------     |     -----------
> +#      | Thread1 |     |     | Thread2 |
> +#      -----------     |     -----------
> +#           |          |          |
> +#      -----------     |     -----------
> +#      |  xskX   |     |     |  xskY   |
>   #      -----------     |     -----------
>   #           |          |          |
>   #      -----------     |     ----------
> @@ -40,6 +49,8 @@
>   #       conflict with any existing interface
>   #   * tests the veth and xsk layers of the topology
>   #
> +# See the source xdpxceiver.c for information on each test
> +#
>   # Kernel configuration:
>   # ---------------------
>   # See "config" file for recommended kernel config options.
> diff --git a/tools/testing/selftests/bpf/test_xsk_skb_nopoll.sh b/tools/testing/selftests/bpf/test_xsk_skb_nopoll.sh
> new file mode 100755
> index 000000000000..96600b0f5136
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/test_xsk_skb_nopoll.sh
> @@ -0,0 +1,20 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright(c) 2020 Intel Corporation.
> +
> +# See test_xsk_prerequisites.sh for detailed information on tests
> +
> +. xsk_prereqs.sh
> +. xsk_env.sh
> +
> +TEST_NAME="SKB NOPOLL"
> +
> +vethXDPgeneric ${VETH0} ${VETH1} ${NS1}
> +
> +params=("-S")
> +execxdpxceiver params
> +
> +retval=$?
> +test_status $retval "${TEST_NAME}"
> +
> +test_exit $retval 0
> diff --git a/tools/testing/selftests/bpf/test_xsk_framework.sh b/tools/testing/selftests/bpf/test_xsk_skb_poll.sh
> similarity index 61%
> rename from tools/testing/selftests/bpf/test_xsk_framework.sh
> rename to tools/testing/selftests/bpf/test_xsk_skb_poll.sh
> index 2e3f099d001c..d152c8a24251 100755
> --- a/tools/testing/selftests/bpf/test_xsk_framework.sh
> +++ b/tools/testing/selftests/bpf/test_xsk_skb_poll.sh
> @@ -7,11 +7,17 @@
>   . xsk_prereqs.sh
>   . xsk_env.sh

Here both xsk_prereqs.sh and xsk_env.sh are executed.
But xsk_env.sh also calls xsk_prereqs.sh. This double
execution of xsk_prereqs.sh is required or is an
oversight?

>   
> -TEST_NAME="XSK FRAMEWORK"
> +TEST_NAME="SKB POLL"
>   
> -test_status $ksft_pass "${TEST_NAME}"
> +vethXDPgeneric ${VETH0} ${VETH1} ${NS1}
> +
> +params=("-S" "-p")
> +execxdpxceiver params
> +
> +retval=$?
> +test_status $retval "${TEST_NAME}"
>   
>   # Must be called in the last test to execute
>   cleanup_exit ${VETH0} ${VETH1} ${NS1}
>   
> -test_exit $ksft_pass 0
> +test_exit $retval 0
> diff --git a/tools/testing/selftests/bpf/xdpxceiver.c b/tools/testing/selftests/bpf/xdpxceiver.c
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