Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[karo-tx-linux.git] / arch / xtensa / kernel / stacktrace.c

diff --git a/arch/xtensa/kernel/stacktrace.c b/arch/xtensa/kernel/stacktrace.c
index e3aff95751833d29a1fa39990fc778d5bde1e262..7d2c317bd98b30eb2a82e2770d0ff236de66fe03 100644 (file)
--- a/arch/xtensa/kernel/stacktrace.c
+++ b/arch/xtensa/kernel/stacktrace.c
@@ -85,3 +85,36 @@ void save_stack_trace(struct stack_trace *trace)
 EXPORT_SYMBOL_GPL(save_stack_trace);
 
 #endif
+
+#ifdef CONFIG_FRAME_POINTER
+
+struct return_addr_data {
+       unsigned long addr;
+       unsigned skip;
+};
+
+static int return_address_cb(struct stackframe *frame, void *data)
+{
+       struct return_addr_data *r = data;
+
+       if (r->skip) {
+               --r->skip;
+               return 0;
+       }
+       if (!kernel_text_address(frame->pc))
+               return 0;
+       r->addr = frame->pc;
+       return 1;
+}
+
+unsigned long return_address(unsigned level)
+{
+       struct return_addr_data r = {
+               .skip = level + 1,
+       };
+       walk_stackframe(stack_pointer(NULL), return_address_cb, &r);
+       return r.addr;
+}
+EXPORT_SYMBOL(return_address);
+
+#endif