selftests/bpf: fix perf_buffer on s390

perf_buffer test fails for exactly the same reason test_attach_probe
used to fail: different nanosleep syscall kprobe name.

Reuse the test_attach_probe fix.

Fixes: ee5cf82c ("selftests/bpf: test perf buffer API")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

tools/testing/selftests/bpf/prog_tests/attach_probe.c

@@ -21,14 +21,6 @@ ssize_t get_base_addr() {
 	return -EINVAL;
 }
 
-#ifdef __x86_64__
-#define SYS_KPROBE_NAME "__x64_sys_nanosleep"
-#elif defined(__s390x__)
-#define SYS_KPROBE_NAME "__s390x_sys_nanosleep"
-#else
-#define SYS_KPROBE_NAME "sys_nanosleep"
-#endif
-
 void test_attach_probe(void)
 {
 	const char *kprobe_name = "kprobe/sys_nanosleep";
@@ -86,7 +78,7 @@ void test_attach_probe(void)
 
 	kprobe_link = bpf_program__attach_kprobe(kprobe_prog,
 						 false /* retprobe */,
-						 SYS_KPROBE_NAME);
+						 SYS_NANOSLEEP_KPROBE_NAME);
 	if (CHECK(IS_ERR(kprobe_link), "attach_kprobe",
 		  "err %ld\n", PTR_ERR(kprobe_link))) {
 		kprobe_link = NULL;
@@ -94,7 +86,7 @@ void test_attach_probe(void)
 	}
 	kretprobe_link = bpf_program__attach_kprobe(kretprobe_prog,
 						    true /* retprobe */,
-						    SYS_KPROBE_NAME);
+						    SYS_NANOSLEEP_KPROBE_NAME);
 	if (CHECK(IS_ERR(kretprobe_link), "attach_kretprobe",
 		  "err %ld\n", PTR_ERR(kretprobe_link))) {
 		kretprobe_link = NULL;

tools/testing/selftests/bpf/prog_tests/perf_buffer.c

@@ -5,12 +5,6 @@
 #include <sys/socket.h>
 #include <test_progs.h>
 
-#ifdef __x86_64__
-#define SYS_KPROBE_NAME "__x64_sys_nanosleep"
-#else
-#define SYS_KPROBE_NAME "sys_nanosleep"
-#endif
-
 static void on_sample(void *ctx, int cpu, void *data, __u32 size)
 {
 	int cpu_data = *(int *)data, duration = 0;
@@ -56,7 +50,7 @@ void test_perf_buffer(void)
 
 	/* attach kprobe */
 	link = bpf_program__attach_kprobe(prog, false /* retprobe */,
-					  SYS_KPROBE_NAME);
+					  SYS_NANOSLEEP_KPROBE_NAME);
 	if (CHECK(IS_ERR(link), "attach_kprobe", "err %ld\n", PTR_ERR(link)))
 		goto out_close;
 

tools/testing/selftests/bpf/test_progs.h

@@ -92,3 +92,11 @@ int compare_map_keys(int map1_fd, int map2_fd);
 int compare_stack_ips(int smap_fd, int amap_fd, int stack_trace_len);
 int extract_build_id(char *build_id, size_t size);
 void *spin_lock_thread(void *arg);
+
+#ifdef __x86_64__
+#define SYS_NANOSLEEP_KPROBE_NAME "__x64_sys_nanosleep"
+#elif defined(__s390x__)
+#define SYS_NANOSLEEP_KPROBE_NAME "__s390x_sys_nanosleep"
+#else
+#define SYS_NANOSLEEP_KPROBE_NAME "sys_nanosleep"
+#endif