[PATCH bpf-next v2 2/2] selftests/bpf: Test BPF_KPROBE_SYSCALL macro

[Hengqi Chen <hengqi.chen@xxxxxxxxx>]

Add tests for the newly added BPF_KPROBE_SYSCALL macro.

Signed-off-by: Hengqi Chen <hengqi.chen@xxxxxxxxx>
---
 .../selftests/bpf/prog_tests/kprobe_syscall.c | 37 +++++++++++++++++++
 .../selftests/bpf/progs/test_kprobe_syscall.c | 34 +++++++++++++++++
 2 files changed, 71 insertions(+)
 create mode 100644 tools/testing/selftests/bpf/prog_tests/kprobe_syscall.c
 create mode 100644 tools/testing/selftests/bpf/progs/test_kprobe_syscall.c

diff --git a/tools/testing/selftests/bpf/prog_tests/kprobe_syscall.c b/tools/testing/selftests/bpf/prog_tests/kprobe_syscall.c
new file mode 100644
index 000000000000..0ac89c987024
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/kprobe_syscall.c
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2022 Hengqi Chen */
+
+#include <test_progs.h>
+#include <sys/prctl.h>
+#include "test_kprobe_syscall.skel.h"
+
+void test_kprobe_syscall(void)
+{
+	struct test_kprobe_syscall *skel;
+	int err;
+
+	skel = test_kprobe_syscall__open();
+	if (!ASSERT_OK_PTR(skel, "test_kprobe_syscall__open"))
+		return;
+
+	skel->rodata->my_pid = getpid();
+
+	err = test_kprobe_syscall__load(skel);
+	if (!ASSERT_OK(err, "test_kprobe_syscall__load"))
+		goto cleanup;
+
+	err = test_kprobe_syscall__attach(skel);
+	if (!ASSERT_OK(err, "test_kprobe_syscall__attach"))
+		goto cleanup;
+
+	prctl(1, 2, 3, 4, 5);
+
+	ASSERT_EQ(skel->bss->option, 1, "BPF_KPROBE_SYSCALL failed");
+	ASSERT_EQ(skel->bss->arg2, 2, "BPF_KPROBE_SYSCALL failed");
+	ASSERT_EQ(skel->bss->arg3, 3, "BPF_KPROBE_SYSCALL failed");
+	ASSERT_EQ(skel->bss->arg4, 4, "BPF_KPROBE_SYSCALL failed");
+	ASSERT_EQ(skel->bss->arg5, 5, "BPF_KPROBE_SYSCALL failed");
+
+cleanup:
+	test_kprobe_syscall__destroy(skel);
+}
diff --git a/tools/testing/selftests/bpf/progs/test_kprobe_syscall.c b/tools/testing/selftests/bpf/progs/test_kprobe_syscall.c
new file mode 100644
index 000000000000..abd59c3d5b59
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_kprobe_syscall.c
@@ -0,0 +1,34 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2022 Hengqi Chen */
+
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_core_read.h>
+#include "bpf_misc.h"
+
+const volatile pid_t my_pid = 0;
+int option = 0;
+unsigned long arg2 = 0;
+unsigned long arg3 = 0;
+unsigned long arg4 = 0;
+unsigned long arg5 = 0;
+
+SEC("kprobe/" SYS_PREFIX "sys_prctl")
+int BPF_KPROBE_SYSCALL(prctl_enter, int opt, unsigned long a2,
+		       unsigned long a3, unsigned long a4, unsigned long a5)
+{
+	pid_t pid = bpf_get_current_pid_tgid() >> 32;
+
+	if (pid != my_pid)
+		return 0;
+
+	option = opt;
+	arg2 = a2;
+	arg3 = a3;
+	arg4 = a4;
+	arg5 = a5;
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";
--
2.30.2