1 files changed, 92 insertions, 0 deletions
diff --git a/tools/perf/util/unwind-libunwind.c b/tools/perf/util/unwind-libunwind.c
new file mode 100644
index 000000000000..cb8be6acfb6f
--- /dev/null
+++ b/tools/perf/util/unwind-libunwind.c
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "unwind.h"
+#include "dso.h"
+#include "map.h"
+#include "thread.h"
+#include "session.h"
+#include "debug.h"
+#include "env.h"
+#include "callchain.h"
+
+struct unwind_libunwind_ops __weak *local_unwind_libunwind_ops;
+struct unwind_libunwind_ops __weak *x86_32_unwind_libunwind_ops;
+struct unwind_libunwind_ops __weak *arm64_unwind_libunwind_ops;
+
+int unwind__prepare_access(struct maps *maps, struct map *map, bool *initialized)
+{
+	const char *arch;
+	enum dso_type dso_type;
+	struct unwind_libunwind_ops *ops = local_unwind_libunwind_ops;
+	struct dso *dso = map__dso(map);
+	struct machine *machine;
+	int err;
+
+	if (!dwarf_callchain_users)
+		return 0;
+
+	if (maps__addr_space(maps)) {
+		pr_debug("unwind: thread map already set, dso=%s\n", dso__name(dso));
+		if (initialized)
+			*initialized = true;
+		return 0;
+	}
+
+	machine = maps__machine(maps);
+	/* env->arch is NULL for live-mode (i.e. perf top) */
+	if (!machine->env || !machine->env->arch)
+		goto out_register;
+
+	dso_type = dso__type(dso, machine);
+	if (dso_type == DSO__TYPE_UNKNOWN)
+		return 0;
+
+	arch = perf_env__arch(machine->env);
+
+	if (!strcmp(arch, "x86")) {
+		if (dso_type != DSO__TYPE_64BIT)
+			ops = x86_32_unwind_libunwind_ops;
+	} else if (!strcmp(arch, "arm64") || !strcmp(arch, "arm")) {
+		if (dso_type == DSO__TYPE_64BIT)
+			ops = arm64_unwind_libunwind_ops;
+	}
+
+	if (!ops) {
+		pr_warning_once("unwind: target platform=%s is not supported\n", arch);
+		return 0;
+	}
+out_register:
+	maps__set_unwind_libunwind_ops(maps, ops);
+
+	err = maps__unwind_libunwind_ops(maps)->prepare_access(maps);
+	if (initialized)
+		*initialized = err ? false : true;
+	return err;
+}
+
+void unwind__flush_access(struct maps *maps)
+{
+	const struct unwind_libunwind_ops *ops = maps__unwind_libunwind_ops(maps);
+
+	if (ops)
+		ops->flush_access(maps);
+}
+
+void unwind__finish_access(struct maps *maps)
+{
+	const struct unwind_libunwind_ops *ops = maps__unwind_libunwind_ops(maps);
+
+	if (ops)
+		ops->finish_access(maps);
+}
+
+int unwind__get_entries(unwind_entry_cb_t cb, void *arg,
+			 struct thread *thread,
+			 struct perf_sample *data, int max_stack,
+			 bool best_effort)
+{
+	const struct unwind_libunwind_ops *ops = maps__unwind_libunwind_ops(thread__maps(thread));
+
+	if (ops)
+		return ops->get_entries(cb, arg, thread, data, max_stack, best_effort);
+	return 0;
+}