Re: [PATCH v2 bpf-next 05/16] selftests/bpf: Test for syscall program type

[Andrii Nakryiko <andrii.nakryiko@gmail.com>]

On Thu, Apr 22, 2021 at 5:26 PM Alexei Starovoitov
<alexei.starovoitov@gmail.com> wrote:
>
> From: Alexei Starovoitov <ast@kernel.org>
>
> bpf_prog_type_syscall is a program that creates a bpf map,
> updates it, and loads another bpf program using bpf_sys_bpf() helper.
>
> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
> ---
>  tools/testing/selftests/bpf/Makefile          |  1 +
>  .../selftests/bpf/prog_tests/syscall.c        | 53 ++++++++++++++
>  tools/testing/selftests/bpf/progs/syscall.c   | 73 +++++++++++++++++++
>  3 files changed, 127 insertions(+)
>  create mode 100644 tools/testing/selftests/bpf/prog_tests/syscall.c
>  create mode 100644 tools/testing/selftests/bpf/progs/syscall.c
>
> diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
> index c5bcdb3d4b12..9fdfdbc61857 100644
> --- a/tools/testing/selftests/bpf/Makefile
> +++ b/tools/testing/selftests/bpf/Makefile
> @@ -278,6 +278,7 @@ MENDIAN=$(if $(IS_LITTLE_ENDIAN),-mlittle-endian,-mbig-endian)
>  CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG))
>  BPF_CFLAGS = -g -D__TARGET_ARCH_$(SRCARCH) $(MENDIAN)                  \
>              -I$(INCLUDE_DIR) -I$(CURDIR) -I$(APIDIR)                   \
> +            -I$(TOOLSINCDIR) \

is this for filter.h? also, please align \ with the previous line


>              -I$(abspath $(OUTPUT)/../usr/include)
>
>  CLANG_CFLAGS = $(CLANG_SYS_INCLUDES) \
> diff --git a/tools/testing/selftests/bpf/prog_tests/syscall.c b/tools/testing/selftests/bpf/prog_tests/syscall.c
> new file mode 100644
> index 000000000000..e550e36bb5da
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/prog_tests/syscall.c
> @@ -0,0 +1,53 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright (c) 2021 Facebook */
> +#include <test_progs.h>
> +#include "syscall.skel.h"
> +
> +struct args {
> +       __u64 log_buf;
> +       __u32 log_size;
> +       int max_entries;
> +       int map_fd;
> +       int prog_fd;
> +};
> +
> +void test_syscall(void)
> +{
> +       static char verifier_log[8192];
> +       struct args ctx = {
> +               .max_entries = 1024,
> +               .log_buf = (uintptr_t) verifier_log,
> +               .log_size = sizeof(verifier_log),
> +       };
> +       struct bpf_prog_test_run_attr tattr = {
> +               .ctx_in = &ctx,
> +               .ctx_size_in = sizeof(ctx),
> +       };
> +       struct syscall *skel = NULL;
> +       __u64 key = 12, value = 0;
> +       __u32 duration = 0;
> +       int err;
> +
> +       skel = syscall__open_and_load();
> +       if (CHECK(!skel, "skel_load", "syscall skeleton failed\n"))
> +               goto cleanup;
> +
> +       tattr.prog_fd = bpf_program__fd(skel->progs.bpf_prog);
> +       err = bpf_prog_test_run_xattr(&tattr);
> +       if (CHECK(err || tattr.retval != 1, "test_run sys_bpf",
> +                 "err %d errno %d retval %d duration %d\n",
> +                 err, errno, tattr.retval, tattr.duration))
> +               goto cleanup;
> +
> +       CHECK(ctx.map_fd <= 0, "map_fd", "fd = %d\n", ctx.map_fd);
> +       CHECK(ctx.prog_fd <= 0, "prog_fd", "fd = %d\n", ctx.prog_fd);

please use ASSERT_xxx() macros everywhere. I've just added
ASSERT_GT(), so once that patch set lands you should have all the
variants you need.

> +       CHECK(memcmp(verifier_log, "processed", sizeof("processed") - 1) != 0,
> +             "verifier_log", "%s\n", verifier_log);
> +
> +       err = bpf_map_lookup_elem(ctx.map_fd, &key, &value);
> +       CHECK(err, "map_lookup", "map_lookup failed\n");
> +       CHECK(value != 34, "invalid_value",
> +             "got value %llu expected %u\n", value, 34);
> +cleanup:
> +       syscall__destroy(skel);
> +}
> diff --git a/tools/testing/selftests/bpf/progs/syscall.c b/tools/testing/selftests/bpf/progs/syscall.c
> new file mode 100644
> index 000000000000..01476f88e45f
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/progs/syscall.c
> @@ -0,0 +1,73 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright (c) 2021 Facebook */
> +#include <linux/stddef.h>
> +#include <linux/bpf.h>
> +#include <bpf/bpf_helpers.h>
> +#include <bpf/bpf_tracing.h>
> +#include <../../tools/include/linux/filter.h>

with TOOLSINCDIR shouldn't this be just <linux/fiter.h>?

> +
> +volatile const int workaround = 1;

not needed anymore?

> +
> +char _license[] SEC("license") = "GPL";
> +
> +struct args {
> +       __u64 log_buf;
> +       __u32 log_size;
> +       int max_entries;
> +       int map_fd;
> +       int prog_fd;
> +};
> +

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