On Tue, Apr 20, 2021 at 12:37 PM Kumar Kartikeya Dwivedi
<memxor@xxxxxxxxx> wrote:
>
> This adds some basic tests for the low level bpf_tc_* API.
>
> Reviewed-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx>
> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>
> ---
> .../selftests/bpf/prog_tests/test_tc_bpf.c | 169 ++++++++++++++++++
> .../selftests/bpf/progs/test_tc_bpf_kern.c | 12 ++
> 2 files changed, 181 insertions(+)
> create mode 100644 tools/testing/selftests/bpf/prog_tests/test_tc_bpf.c
we normally don't call prog_test's files with "test_" prefix, it can
be just tc_bpf.c (or just tc.c)
> create mode 100644 tools/testing/selftests/bpf/progs/test_tc_bpf_kern.c
we also don't typically call BPF source code files with _kern suffix,
just test_tc_bpf.c would be more in line with most common case
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/test_tc_bpf.c b/tools/testing/selftests/bpf/prog_tests/test_tc_bpf.c
> new file mode 100644
> index 000000000000..563a3944553c
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/prog_tests/test_tc_bpf.c
> @@ -0,0 +1,169 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#include <linux/bpf.h>
> +#include <linux/err.h>
> +#include <linux/limits.h>
> +#include <bpf/libbpf.h>
> +#include <errno.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <test_progs.h>
> +#include <linux/if_ether.h>
> +
> +#define LO_IFINDEX 1
> +
> +static int test_tc_internal(int fd, __u32 parent_id)
> +{
> + DECLARE_LIBBPF_OPTS(bpf_tc_opts, opts, .handle = 1, .priority = 10,
> + .class_id = TC_H_MAKE(1UL << 16, 1));
> + struct bpf_tc_attach_id id = {};
> + struct bpf_tc_info info = {};
> + int ret;
> +
> + ret = bpf_tc_attach(fd, LO_IFINDEX, parent_id, &opts, &id);
> + if (!ASSERT_EQ(ret, 0, "bpf_tc_attach"))
> + return ret;
> +
> + ret = bpf_tc_get_info(LO_IFINDEX, parent_id, &id, &info);
> + if (!ASSERT_EQ(ret, 0, "bpf_tc_get_info"))
> + goto end;
> +
> + if (!ASSERT_EQ(info.id.handle, id.handle, "handle mismatch") ||
> + !ASSERT_EQ(info.id.priority, id.priority, "priority mismatch") ||
> + !ASSERT_EQ(info.id.handle, 1, "handle incorrect") ||
> + !ASSERT_EQ(info.chain_index, 0, "chain_index incorrect") ||
> + !ASSERT_EQ(info.id.priority, 10, "priority incorrect") ||
> + !ASSERT_EQ(info.class_id, TC_H_MAKE(1UL << 16, 1),
> + "class_id incorrect") ||
> + !ASSERT_EQ(info.protocol, ETH_P_ALL, "protocol incorrect"))
> + goto end;
> +
> + opts.replace = true;
> + ret = bpf_tc_attach(fd, LO_IFINDEX, parent_id, &opts, &id);
> + if (!ASSERT_EQ(ret, 0, "bpf_tc_attach in replace mode"))
> + return ret;
> +
> + /* Demonstrate changing attributes */
> + opts.class_id = TC_H_MAKE(1UL << 16, 2);
> +
> + ret = bpf_tc_attach(fd, LO_IFINDEX, parent_id, &opts, &id);
> + if (!ASSERT_EQ(ret, 0, "bpf_tc attach in replace mode"))
> + goto end;
> +
> + ret = bpf_tc_get_info(LO_IFINDEX, parent_id, &id, &info);
> + if (!ASSERT_EQ(ret, 0, "bpf_tc_get_info"))
> + goto end;
> +
> + if (!ASSERT_EQ(info.class_id, TC_H_MAKE(1UL << 16, 2),
> + "class_id incorrect after replace"))
> + goto end;
> + if (!ASSERT_EQ(info.bpf_flags & TCA_BPF_FLAG_ACT_DIRECT, 1,
> + "direct action mode not set"))
> + goto end;
> +
> +end:
> + ret = bpf_tc_detach(LO_IFINDEX, parent_id, &id);
> + ASSERT_EQ(ret, 0, "detach failed");
> + return ret;
> +}
> +
> +int test_tc_info(int fd)
> +{
> + DECLARE_LIBBPF_OPTS(bpf_tc_opts, opts, .handle = 1, .priority = 10,
> + .class_id = TC_H_MAKE(1UL << 16, 1));
> + struct bpf_tc_attach_id id = {}, old;
> + struct bpf_tc_info info = {};
> + int ret;
> +
> + ret = bpf_tc_attach(fd, LO_IFINDEX, BPF_TC_CLSACT_INGRESS, &opts, &id);
> + if (!ASSERT_EQ(ret, 0, "bpf_tc_attach"))
> + return ret;
> + old = id;
> +
> + ret = bpf_tc_get_info(LO_IFINDEX, BPF_TC_CLSACT_INGRESS, &id, &info);
> + if (!ASSERT_EQ(ret, 0, "bpf_tc_get_info"))
> + goto end_old;
> +
> + if (!ASSERT_EQ(info.id.handle, id.handle, "handle mismatch") ||
> + !ASSERT_EQ(info.id.priority, id.priority, "priority mismatch") ||
> + !ASSERT_EQ(info.id.handle, 1, "handle incorrect") ||
> + !ASSERT_EQ(info.chain_index, 0, "chain_index incorrect") ||
> + !ASSERT_EQ(info.id.priority, 10, "priority incorrect") ||
> + !ASSERT_EQ(info.class_id, TC_H_MAKE(1UL << 16, 1),
> + "class_id incorrect") ||
> + !ASSERT_EQ(info.protocol, ETH_P_ALL, "protocol incorrect"))
> + goto end_old;
> +
> + /* choose a priority */
> + opts.priority = 0;
> + ret = bpf_tc_attach(fd, LO_IFINDEX, BPF_TC_CLSACT_INGRESS, &opts, &id);
> + if (!ASSERT_EQ(ret, 0, "bpf_tc_attach"))
> + goto end_old;
> +
> + ret = bpf_tc_get_info(LO_IFINDEX, BPF_TC_CLSACT_INGRESS, &id, &info);
> + if (!ASSERT_EQ(ret, 0, "bpf_tc_get_info"))
> + goto end;
> +
> + if (!ASSERT_NEQ(id.priority, old.priority, "filter priority mismatch"))
> + goto end;
> + if (!ASSERT_EQ(info.id.priority, id.priority, "priority mismatch"))
> + goto end;
> +
> +end:
> + ret = bpf_tc_detach(LO_IFINDEX, BPF_TC_CLSACT_INGRESS, &id);
> + ASSERT_EQ(ret, 0, "detach failed");
> +end_old:
> + ret = bpf_tc_detach(LO_IFINDEX, BPF_TC_CLSACT_INGRESS, &old);
> + ASSERT_EQ(ret, 0, "detach failed");
> + return ret;
> +}
> +
> +void test_test_tc_bpf(void)
test_test_ tautology, drop one test?
> +{
> + const char *file = "./test_tc_bpf_kern.o";
please use BPF skeleton instead, see lots of other selftests doing
that already. You won't even need find_program_by_{name,title}, among
other things.
> + struct bpf_program *clsp;
> + struct bpf_object *obj;
> + int cls_fd, ret;
> +
> + obj = bpf_object__open(file);
> + if (!ASSERT_OK_PTR(obj, "bpf_object__open"))
> + return;
> +
> + clsp = bpf_object__find_program_by_title(obj, "classifier");
> + if (!ASSERT_OK_PTR(clsp, "bpf_object__find_program_by_title"))
> + goto end;
> +
> + ret = bpf_object__load(obj);
> + if (!ASSERT_EQ(ret, 0, "bpf_object__load"))
> + goto end;
> +
> + cls_fd = bpf_program__fd(clsp);
> +
> + system("tc qdisc del dev lo clsact");
can this fail? also why is this necessary? it's still not possible to
do anything with only libbpf APIs?
> +
> + ret = test_tc_internal(cls_fd, BPF_TC_CLSACT_INGRESS);
> + if (!ASSERT_EQ(ret, 0, "test_tc_internal INGRESS"))
> + goto end;
> +
> + if (!ASSERT_EQ(system("tc qdisc del dev lo clsact"), 0,
> + "clsact qdisc delete failed"))
> + goto end;
> +
> + ret = test_tc_info(cls_fd);
> + if (!ASSERT_EQ(ret, 0, "test_tc_info"))
> + goto end;
> +
> + if (!ASSERT_EQ(system("tc qdisc del dev lo clsact"), 0,
> + "clsact qdisc delete failed"))
> + goto end;
> +
> + ret = test_tc_internal(cls_fd, BPF_TC_CLSACT_EGRESS);
> + if (!ASSERT_EQ(ret, 0, "test_tc_internal EGRESS"))
> + goto end;
> +
> + ASSERT_EQ(system("tc qdisc del dev lo clsact"), 0,
> + "clsact qdisc delete failed");
> +
> +end:
> + bpf_object__close(obj);
> +}
> diff --git a/tools/testing/selftests/bpf/progs/test_tc_bpf_kern.c b/tools/testing/selftests/bpf/progs/test_tc_bpf_kern.c
> new file mode 100644
> index 000000000000..18a3a7ed924a
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/progs/test_tc_bpf_kern.c
> @@ -0,0 +1,12 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#include <linux/bpf.h>
> +#include <bpf/bpf_helpers.h>
> +
> +/* Dummy prog to test TC-BPF API */
> +
> +SEC("classifier")
> +int cls(struct __sk_buff *skb)
> +{
> + return 0;
> +}
> --
> 2.30.2
>
