This source file includes following definitions.
- unwind_frame
- walk_stackframe
- save_trace
- __save_stack_trace
- save_stack_trace_regs
- save_stack_trace_tsk
- save_stack_trace
1
2 #include <linux/export.h>
3 #include <linux/sched.h>
4 #include <linux/sched/debug.h>
5 #include <linux/stacktrace.h>
6
7 #include <asm/sections.h>
8 #include <asm/stacktrace.h>
9 #include <asm/traps.h>
10
11 #if defined(CONFIG_FRAME_POINTER) && !defined(CONFIG_ARM_UNWIND)
12
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27
28 int notrace unwind_frame(struct stackframe *frame)
29 {
30 unsigned long high, low;
31 unsigned long fp = frame->fp;
32
33
34 low = frame->sp;
35 high = ALIGN(low, THREAD_SIZE);
36
37
38 if (fp < low + 12 || fp > high - 4)
39 return -EINVAL;
40
41
42 frame->fp = *(unsigned long *)(fp - 12);
43 frame->sp = *(unsigned long *)(fp - 8);
44 frame->pc = *(unsigned long *)(fp - 4);
45
46 return 0;
47 }
48 #endif
49
50 void notrace walk_stackframe(struct stackframe *frame,
51 int (*fn)(struct stackframe *, void *), void *data)
52 {
53 while (1) {
54 int ret;
55
56 if (fn(frame, data))
57 break;
58 ret = unwind_frame(frame);
59 if (ret < 0)
60 break;
61 }
62 }
63 EXPORT_SYMBOL(walk_stackframe);
64
65 #ifdef CONFIG_STACKTRACE
66 struct stack_trace_data {
67 struct stack_trace *trace;
68 unsigned int no_sched_functions;
69 unsigned int skip;
70 };
71
72 static int save_trace(struct stackframe *frame, void *d)
73 {
74 struct stack_trace_data *data = d;
75 struct stack_trace *trace = data->trace;
76 struct pt_regs *regs;
77 unsigned long addr = frame->pc;
78
79 if (data->no_sched_functions && in_sched_functions(addr))
80 return 0;
81 if (data->skip) {
82 data->skip--;
83 return 0;
84 }
85
86 trace->entries[trace->nr_entries++] = addr;
87
88 if (trace->nr_entries >= trace->max_entries)
89 return 1;
90
91 if (!in_entry_text(frame->pc))
92 return 0;
93
94 regs = (struct pt_regs *)frame->sp;
95
96 trace->entries[trace->nr_entries++] = regs->ARM_pc;
97
98 return trace->nr_entries >= trace->max_entries;
99 }
100
101
102 static noinline void __save_stack_trace(struct task_struct *tsk,
103 struct stack_trace *trace, unsigned int nosched)
104 {
105 struct stack_trace_data data;
106 struct stackframe frame;
107
108 data.trace = trace;
109 data.skip = trace->skip;
110 data.no_sched_functions = nosched;
111
112 if (tsk != current) {
113 #ifdef CONFIG_SMP
114
115
116
117
118
119 return;
120 #else
121 frame.fp = thread_saved_fp(tsk);
122 frame.sp = thread_saved_sp(tsk);
123 frame.lr = 0;
124 frame.pc = thread_saved_pc(tsk);
125 #endif
126 } else {
127
128 data.skip += 2;
129 frame.fp = (unsigned long)__builtin_frame_address(0);
130 frame.sp = current_stack_pointer;
131 frame.lr = (unsigned long)__builtin_return_address(0);
132 frame.pc = (unsigned long)__save_stack_trace;
133 }
134
135 walk_stackframe(&frame, save_trace, &data);
136 }
137
138 void save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace)
139 {
140 struct stack_trace_data data;
141 struct stackframe frame;
142
143 data.trace = trace;
144 data.skip = trace->skip;
145 data.no_sched_functions = 0;
146
147 frame.fp = regs->ARM_fp;
148 frame.sp = regs->ARM_sp;
149 frame.lr = regs->ARM_lr;
150 frame.pc = regs->ARM_pc;
151
152 walk_stackframe(&frame, save_trace, &data);
153 }
154
155 void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
156 {
157 __save_stack_trace(tsk, trace, 1);
158 }
159 EXPORT_SYMBOL(save_stack_trace_tsk);
160
161 void save_stack_trace(struct stack_trace *trace)
162 {
163 __save_stack_trace(current, trace, 0);
164 }
165 EXPORT_SYMBOL_GPL(save_stack_trace);
166 #endif