xref: /openbmc/linux/arch/sh/kernel/dumpstack.c (revision 63dc02bd)
1 /*
2  *  Copyright (C) 1991, 1992  Linus Torvalds
3  *  Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
4  *  Copyright (C) 2009  Matt Fleming
5  */
6 #include <linux/kallsyms.h>
7 #include <linux/ftrace.h>
8 #include <linux/debug_locks.h>
9 #include <asm/unwinder.h>
10 #include <asm/stacktrace.h>
11 
12 void printk_address(unsigned long address, int reliable)
13 {
14 	printk(" [<%p>] %s%pS\n", (void *) address,
15 			reliable ? "" : "? ", (void *) address);
16 }
17 
18 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
19 static void
20 print_ftrace_graph_addr(unsigned long addr, void *data,
21 			const struct stacktrace_ops *ops,
22 			struct thread_info *tinfo, int *graph)
23 {
24 	struct task_struct *task = tinfo->task;
25 	unsigned long ret_addr;
26 	int index = task->curr_ret_stack;
27 
28 	if (addr != (unsigned long)return_to_handler)
29 		return;
30 
31 	if (!task->ret_stack || index < *graph)
32 		return;
33 
34 	index -= *graph;
35 	ret_addr = task->ret_stack[index].ret;
36 
37 	ops->address(data, ret_addr, 1);
38 
39 	(*graph)++;
40 }
41 #else
42 static inline void
43 print_ftrace_graph_addr(unsigned long addr, void *data,
44 			const struct stacktrace_ops *ops,
45 			struct thread_info *tinfo, int *graph)
46 { }
47 #endif
48 
49 void
50 stack_reader_dump(struct task_struct *task, struct pt_regs *regs,
51 		  unsigned long *sp, const struct stacktrace_ops *ops,
52 		  void *data)
53 {
54 	struct thread_info *context;
55 	int graph = 0;
56 
57 	context = (struct thread_info *)
58 		((unsigned long)sp & (~(THREAD_SIZE - 1)));
59 
60 	while (!kstack_end(sp)) {
61 		unsigned long addr = *sp++;
62 
63 		if (__kernel_text_address(addr)) {
64 			ops->address(data, addr, 1);
65 
66 			print_ftrace_graph_addr(addr, data, ops,
67 						context, &graph);
68 		}
69 	}
70 }
71 
72 static int print_trace_stack(void *data, char *name)
73 {
74 	printk("%s <%s> ", (char *)data, name);
75 	return 0;
76 }
77 
78 /*
79  * Print one address/symbol entries per line.
80  */
81 static void print_trace_address(void *data, unsigned long addr, int reliable)
82 {
83 	printk(data);
84 	printk_address(addr, reliable);
85 }
86 
87 static const struct stacktrace_ops print_trace_ops = {
88 	.stack = print_trace_stack,
89 	.address = print_trace_address,
90 };
91 
92 void show_trace(struct task_struct *tsk, unsigned long *sp,
93 		struct pt_regs *regs)
94 {
95 	if (regs && user_mode(regs))
96 		return;
97 
98 	printk("\nCall trace:\n");
99 
100 	unwind_stack(tsk, regs, sp, &print_trace_ops, "");
101 
102 	printk("\n");
103 
104 	if (!tsk)
105 		tsk = current;
106 
107 	debug_show_held_locks(tsk);
108 }
109