v4.19.13 snapshot.
diff --git a/tools/include/linux/stacktrace.h b/tools/include/linux/stacktrace.h
new file mode 100644
index 0000000..ae343ac
--- /dev/null
+++ b/tools/include/linux/stacktrace.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LIBLOCKDEP_LINUX_STACKTRACE_H_
+#define _LIBLOCKDEP_LINUX_STACKTRACE_H_
+
+#include <execinfo.h>
+
+struct stack_trace {
+ unsigned int nr_entries, max_entries;
+ unsigned long *entries;
+ int skip;
+};
+
+static inline void print_stack_trace(struct stack_trace *trace, int spaces)
+{
+ backtrace_symbols_fd((void **)trace->entries, trace->nr_entries, 1);
+}
+
+#define save_stack_trace(trace) \
+ ((trace)->nr_entries = \
+ backtrace((void **)(trace)->entries, (trace)->max_entries))
+
+static inline int dump_stack(void)
+{
+ void *array[64];
+ size_t size;
+
+ size = backtrace(array, 64);
+ backtrace_symbols_fd(array, size, 1);
+
+ return 0;
+}
+
+#endif