1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Most of this ideas comes from x86.
4  *
5  * Copyright (C) 2022 Loongson Technology Corporation Limited
6  */
7 #ifndef _ASM_UNWIND_H
8 #define _ASM_UNWIND_H
9 
10 #include <linux/sched.h>
11 
12 #include <asm/stacktrace.h>
13 
14 enum unwinder_type {
15 	UNWINDER_GUESS,
16 	UNWINDER_PROLOGUE,
17 };
18 
19 struct unwind_state {
20 	char type; /* UNWINDER_XXX */
21 	struct stack_info stack_info;
22 	struct task_struct *task;
23 	bool first, error, is_ftrace;
24 	int graph_idx;
25 	unsigned long sp, pc, ra;
26 };
27 
28 void unwind_start(struct unwind_state *state,
29 		  struct task_struct *task, struct pt_regs *regs);
30 bool unwind_next_frame(struct unwind_state *state);
31 unsigned long unwind_get_return_address(struct unwind_state *state);
32 
33 static inline bool unwind_done(struct unwind_state *state)
34 {
35 	return state->stack_info.type == STACK_TYPE_UNKNOWN;
36 }
37 
38 static inline bool unwind_error(struct unwind_state *state)
39 {
40 	return state->error;
41 }
42 
43 #endif /* _ASM_UNWIND_H */
44