Re: [PATCH 18/19] selftests/bpf: Add fentry/fexit multi func test
From: Andrii Nakryiko <hidden>
Date: 2021-06-09 05:42:49
Also in:
bpf
On Sat, Jun 5, 2021 at 4:13 AM Jiri Olsa [off-list ref] wrote:
Adding selftest for fentry/fexit multi func test that attaches
to bpf_fentry_test* functions and checks argument values based
on the processed function.
When multi_arg_check is used from 2 different places I'm getting
compilation fail, which I did not deciphered yet:
$ CLANG=/opt/clang/bin/clang LLC=/opt/clang/bin/llc make
CLNG-BPF [test_maps] fentry_fexit_multi_test.o
progs/fentry_fexit_multi_test.c:18:2: error: too many args to t24: i64 = \
GlobalAddress<void (i64, i64, i64, i64, i64, i64, i64, i64*)* @multi_arg_check> 0, \
progs/fentry_fexit_multi_test.c:18:2 @[ progs/fentry_fexit_multi_test.c:16:5 ]
multi_arg_check(ip, a, b, c, d, e, f, &test1_arg_result);
^
progs/fentry_fexit_multi_test.c:25:2: error: too many args to t32: i64 = \
GlobalAddress<void (i64, i64, i64, i64, i64, i64, i64, i64*)* @multi_arg_check> 0, \
progs/fentry_fexit_multi_test.c:25:2 @[ progs/fentry_fexit_multi_test.c:23:5 ]
multi_arg_check(ip, a, b, c, d, e, f, &test2_arg_result);
^
In file included from progs/fentry_fexit_multi_test.c:5:
/home/jolsa/linux-qemu/tools/testing/selftests/bpf/multi_check.h:9:6: error: defined with too many args
void multi_arg_check(unsigned long ip, __u64 a, __u64 b, __u64 c, __u64 d, __u64 e, __u64 f, __u64 *test_result)
^
/home/jolsa/linux-qemu/tools/testing/selftests/bpf/multi_check.h:9:6: error: defined with too many args
/home/jolsa/linux-qemu/tools/testing/selftests/bpf/multi_check.h:9:6: error: defined with too many args
5 errors generated.
make: *** [Makefile:470: /home/jolsa/linux-qemu/tools/testing/selftests/bpf/fentry_fexit_multi_test.o] Error 1
I can fix that by defining 2 separate multi_arg_check functions
with different names, which I did in follow up temporaary patch.
Not sure I'm hitting some clang/bpf limitation in here?don't know about clang limitations, but we should use static linking proper anyways
quoted hunk ↗ jump to hunk
Signed-off-by: Jiri Olsa <jolsa@kernel.org> --- .../bpf/prog_tests/fentry_fexit_multi_test.c | 52 +++++++++++++++++++ .../bpf/progs/fentry_fexit_multi_test.c | 28 ++++++++++ 2 files changed, 80 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/fentry_fexit_multi_test.c create mode 100644 tools/testing/selftests/bpf/progs/fentry_fexit_multi_test.cdiff --git a/tools/testing/selftests/bpf/prog_tests/fentry_fexit_multi_test.c b/tools/testing/selftests/bpf/prog_tests/fentry_fexit_multi_test.c new file mode 100644 index 000000000000..76f917ad843d --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/fentry_fexit_multi_test.c@@ -0,0 +1,52 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <test_progs.h> +#include "fentry_fexit_multi_test.skel.h" + +void test_fentry_fexit_multi_test(void) +{ + DECLARE_LIBBPF_OPTS(bpf_link_update_opts, link_upd_opts); + struct fentry_fexit_multi_test *skel = NULL; + unsigned long long *bpf_fentry_test; + __u32 duration = 0, retval; + struct bpf_link *link; + int err, prog_fd; + + skel = fentry_fexit_multi_test__open_and_load(); + if (!ASSERT_OK_PTR(skel, "fentry_multi_skel_load")) + goto cleanup; + + bpf_fentry_test = &skel->bss->bpf_fentry_test[0]; + ASSERT_OK(kallsyms_find("bpf_fentry_test1", &bpf_fentry_test[0]), "kallsyms_find"); + ASSERT_OK(kallsyms_find("bpf_fentry_test2", &bpf_fentry_test[1]), "kallsyms_find"); + ASSERT_OK(kallsyms_find("bpf_fentry_test3", &bpf_fentry_test[2]), "kallsyms_find"); + ASSERT_OK(kallsyms_find("bpf_fentry_test4", &bpf_fentry_test[3]), "kallsyms_find"); + ASSERT_OK(kallsyms_find("bpf_fentry_test5", &bpf_fentry_test[4]), "kallsyms_find"); + ASSERT_OK(kallsyms_find("bpf_fentry_test6", &bpf_fentry_test[5]), "kallsyms_find"); + ASSERT_OK(kallsyms_find("bpf_fentry_test7", &bpf_fentry_test[6]), "kallsyms_find"); + ASSERT_OK(kallsyms_find("bpf_fentry_test8", &bpf_fentry_test[7]), "kallsyms_find"); + + link = bpf_program__attach(skel->progs.test1); + if (!ASSERT_OK_PTR(link, "attach_fentry_fexit")) + goto cleanup; + + err = bpf_link_update(bpf_link__fd(link), + bpf_program__fd(skel->progs.test2), + NULL); + if (!ASSERT_OK(err, "bpf_link_update")) + goto cleanup_link; + + prog_fd = bpf_program__fd(skel->progs.test1); + err = bpf_prog_test_run(prog_fd, 1, NULL, 0, + NULL, NULL, &retval, &duration); + ASSERT_OK(err, "test_run"); + ASSERT_EQ(retval, 0, "test_run"); + + ASSERT_EQ(skel->bss->test1_arg_result, 8, "test1_arg_result"); + ASSERT_EQ(skel->bss->test2_arg_result, 8, "test2_arg_result"); + ASSERT_EQ(skel->bss->test2_ret_result, 8, "test2_ret_result"); + +cleanup_link: + bpf_link__destroy(link); +cleanup: + fentry_fexit_multi_test__destroy(skel); +}diff --git a/tools/testing/selftests/bpf/progs/fentry_fexit_multi_test.c b/tools/testing/selftests/bpf/progs/fentry_fexit_multi_test.c new file mode 100644 index 000000000000..e25ab0085399 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/fentry_fexit_multi_test.c@@ -0,0 +1,28 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_tracing.h> +#include "multi_check.h" + +char _license[] SEC("license") = "GPL"; + +unsigned long long bpf_fentry_test[8]; + +__u64 test1_arg_result = 0; +__u64 test2_arg_result = 0; +__u64 test2_ret_result = 0; + +SEC("fentry.multi/bpf_fentry_test*") +int BPF_PROG(test1, unsigned long ip, __u64 a, __u64 b, __u64 c, __u64 d, __u64 e, __u64 f) +{ + multi_arg_check(ip, a, b, c, d, e, f, &test1_arg_result); + return 0; +} + +SEC("fexit.multi/") +int BPF_PROG(test2, unsigned long ip, __u64 a, __u64 b, __u64 c, __u64 d, __u64 e, __u64 f, int ret) +{ + multi_arg_check(ip, a, b, c, d, e, f, &test2_arg_result); + multi_ret_check(ip, ret, &test2_ret_result); + return 0; +} --2.31.1