On 12/4/21 6:07 AM, Jiri Olsa wrote:
Adding tests for get_func_[arg|ret|arg_cnt] helpers.
Using these helpers in fentry/fexit/fmod_ret programs.
Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
---
.../bpf/prog_tests/get_func_args_test.c | 38 ++++++
.../selftests/bpf/progs/get_func_args_test.c | 112 ++++++++++++++++++
2 files changed, 150 insertions(+)
create mode 100644 tools/testing/selftests/bpf/prog_tests/get_func_args_test.c
create mode 100644 tools/testing/selftests/bpf/progs/get_func_args_test.c
diff --git a/tools/testing/selftests/bpf/prog_tests/get_func_args_test.c b/tools/testing/selftests/bpf/prog_tests/get_func_args_test.c
new file mode 100644
index 000000000000..c24807ae4361
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/get_func_args_test.c
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <test_progs.h>
+#include "get_func_args_test.skel.h"
+
+void test_get_func_args_test(void)
+{
+ struct get_func_args_test *skel = NULL;
+ __u32 duration = 0, retval;
+ int err, prog_fd;
+
+ skel = get_func_args_test__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "get_func_args_test__open_and_load"))
+ return;
+
+ err = get_func_args_test__attach(skel);
+ if (!ASSERT_OK(err, "get_func_args_test__attach"))
+ goto cleanup;
+
+ 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");
+
+ prog_fd = bpf_program__fd(skel->progs.fmod_ret_test);
+ err = bpf_prog_test_run(prog_fd, 1, NULL, 0,
+ NULL, NULL, &retval, &duration);
+ ASSERT_OK(err, "test_run");
+ ASSERT_EQ(retval, 1234, "test_run");
are the other two programs executed implicitly during one of those test
runs? Can you please leave a small comment somewhere here if that's true?
+
+ ASSERT_EQ(skel->bss->test1_result, 1, "test1_result");
+ ASSERT_EQ(skel->bss->test2_result, 1, "test2_result");
+ ASSERT_EQ(skel->bss->test3_result, 1, "test3_result");
+ ASSERT_EQ(skel->bss->test4_result, 1, "test4_result");
+
+cleanup:
+ get_func_args_test__destroy(skel);
+}
diff --git a/tools/testing/selftests/bpf/progs/get_func_args_test.c b/tools/testing/selftests/bpf/progs/get_func_args_test.c
new file mode 100644
index 000000000000..0d0a67c849ae
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/get_func_args_test.c
@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include <errno.h>
+
+char _license[] SEC("license") = "GPL";
+
+__u64 test1_result = 0;
+SEC("fentry/bpf_fentry_test1")
+int BPF_PROG(test1)
+{
+ __u64 cnt = bpf_get_func_arg_cnt(ctx);
+ __u64 a = 0, z = 0, ret = 0;
+ __s64 err;
+
+ test1_result = cnt == 1;
+
+ /* valid arguments */
+ err = bpf_get_func_arg(ctx, 0, &a);
+ test1_result &= err == 0 && (int) a == 1;
int cast unnecessary? but some ()'s wouldn't hurt...
+
+ /* not valid argument */
+ err = bpf_get_func_arg(ctx, 1, &z);
+ test1_result &= err == -EINVAL;
+
+ /* return value fails in fentry */
+ err = bpf_get_func_ret(ctx, &ret);
+ test1_result &= err == -EINVAL;
+ return 0;
+}
+
+__u64 test2_result = 0;
+SEC("fexit/bpf_fentry_test2")
+int BPF_PROG(test2)
+{
+ __u64 cnt = bpf_get_func_arg_cnt(ctx);
+ __u64 a = 0, b = 0, z = 0, ret = 0;
+ __s64 err;
+
+ test2_result = cnt == 2;
+
+ /* valid arguments */
+ err = bpf_get_func_arg(ctx, 0, &a);
+ test2_result &= err == 0 && (int) a == 2;
+
+ err = bpf_get_func_arg(ctx, 1, &b);
+ test2_result &= err == 0 && b == 3;
+
+ /* not valid argument */
+ err = bpf_get_func_arg(ctx, 2, &z);
+ test2_result &= err == -EINVAL;
+
+ /* return value */
+ err = bpf_get_func_ret(ctx, &ret);
+ test2_result &= err == 0 && ret == 5;
+ return 0;
+}
+
+__u64 test3_result = 0;
+SEC("fmod_ret/bpf_modify_return_test")
+int BPF_PROG(fmod_ret_test, int _a, int *_b, int _ret)
+{
+ __u64 cnt = bpf_get_func_arg_cnt(ctx);
+ __u64 a = 0, b = 0, z = 0, ret = 0;
+ __s64 err;
+
+ test3_result = cnt == 2;
+
+ /* valid arguments */
+ err = bpf_get_func_arg(ctx, 0, &a);
+ test3_result &= err == 0 && (int) a == 1;
+
+ err = bpf_get_func_arg(ctx, 1, &b);
+ test3_result &= err == 0;
why no checking of b value here?
+
+ /* not valid argument */
+ err = bpf_get_func_arg(ctx, 2, &z);
+ test3_result &= err == -EINVAL;
+
+ /* return value */
+ err = bpf_get_func_ret(ctx, &ret);
+ test3_result &= err == 0 && ret == 0;
+ return 1234;
+}
+
+__u64 test4_result = 0;
+SEC("fexit/bpf_modify_return_test")
+int BPF_PROG(fexit_test, int _a, __u64 _b, int _ret)
+{
+ __u64 cnt = bpf_get_func_arg_cnt(ctx);
+ __u64 a = 0, b = 0, z = 0, ret = 0;
+ __s64 err;
+
+ test4_result = cnt == 2;
+
+ /* valid arguments */
+ err = bpf_get_func_arg(ctx, 0, &a);
+ test4_result &= err == 0 && (int) a == 1;
+
+ err = bpf_get_func_arg(ctx, 1, &b);
+ test4_result &= err == 0;
same, for consistency, b should have been checked, no?
+
+ /* not valid argument */
+ err = bpf_get_func_arg(ctx, 2, &z);
+ test4_result &= err == -EINVAL;
+
+ /* return value */
+ err = bpf_get_func_ret(ctx, &ret);
+ test4_result &= err == 0 && ret == 1234;
+ return 0;
+}
