selftests/bpf: Add stacktrace ips test for kprobe_multi/kretprobe_multi

Adding test that attaches kprobe/kretprobe multi and verifies the
ORC stacktrace matches expected functions.

Adding bpf_testmod_stacktrace_test function to bpf_testmod kernel
module which is called through several functions so we get reliable
call path for stacktrace.

The test is only for ORC unwinder to keep it simple.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20251104215405.168643-4-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>

1 files changed, 41 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/progs/stacktrace_ips.c b/tools/testing/selftests/bpf/progs/stacktrace_ips.c
new file mode 100644
index 000000000000..e2eb30945c1b
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/stacktrace_ips.c
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2018 Facebook
+
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+#ifndef PERF_MAX_STACK_DEPTH
+#define PERF_MAX_STACK_DEPTH         127
+#endif
+
+typedef __u64 stack_trace_t[PERF_MAX_STACK_DEPTH];
+
+struct {
+	__uint(type, BPF_MAP_TYPE_STACK_TRACE);
+	__uint(max_entries, 16384);
+	__type(key, __u32);
+	__type(value, stack_trace_t);
+} stackmap SEC(".maps");
+
+extern bool CONFIG_UNWINDER_ORC __kconfig __weak;
+
+/*
+ * This function is here to have CONFIG_UNWINDER_ORC
+ * used and added to object BTF.
+ */
+int unused(void)
+{
+	return CONFIG_UNWINDER_ORC ? 0 : 1;
+}
+
+__u32 stack_key;
+
+SEC("kprobe.multi")
+int kprobe_multi_test(struct pt_regs *ctx)
+{
+	stack_key = bpf_get_stackid(ctx, &stackmap, 0);
+	return 0;
+}
+
+char _license[] SEC("license") = "GPL";