xref: /linux-6.15/arch/sh/kernel/stacktrace.c (revision 0eff9f66)
1 /*
2  * arch/sh/kernel/stacktrace.c
3  *
4  * Stack trace management functions
5  *
6  *  Copyright (C) 2006 - 2008  Paul Mundt
7  *
8  * This file is subject to the terms and conditions of the GNU General Public
9  * License.  See the file "COPYING" in the main directory of this archive
10  * for more details.
11  */
12 #include <linux/sched.h>
13 #include <linux/stacktrace.h>
14 #include <linux/thread_info.h>
15 #include <linux/module.h>
16 #include <asm/unwinder.h>
17 #include <asm/ptrace.h>
18 #include <asm/stacktrace.h>
19 
20 static void save_stack_warning(void *data, char *msg)
21 {
22 }
23 
24 static void
25 save_stack_warning_symbol(void *data, char *msg, unsigned long symbol)
26 {
27 }
28 
29 static int save_stack_stack(void *data, char *name)
30 {
31 	return 0;
32 }
33 
34 /*
35  * Save stack-backtrace addresses into a stack_trace buffer.
36  */
37 static void save_stack_address(void *data, unsigned long addr, int reliable)
38 {
39 	struct stack_trace *trace = data;
40 
41 	if (trace->skip > 0) {
42 		trace->skip--;
43 		return;
44 	}
45 
46 	if (trace->nr_entries < trace->max_entries)
47 		trace->entries[trace->nr_entries++] = addr;
48 }
49 
50 static const struct stacktrace_ops save_stack_ops = {
51 	.warning = save_stack_warning,
52 	.warning_symbol = save_stack_warning_symbol,
53 	.stack = save_stack_stack,
54 	.address = save_stack_address,
55 };
56 
57 void save_stack_trace(struct stack_trace *trace)
58 {
59 	unsigned long *sp = (unsigned long *)current_stack_pointer;
60 
61 	unwind_stack(current, NULL, sp,  &save_stack_ops, trace);
62 }
63 EXPORT_SYMBOL_GPL(save_stack_trace);
64 
65 static void
66 save_stack_address_nosched(void *data, unsigned long addr, int reliable)
67 {
68 	struct stack_trace *trace = (struct stack_trace *)data;
69 
70 	if (in_sched_functions(addr))
71 		return;
72 
73 	if (trace->skip > 0) {
74 		trace->skip--;
75 		return;
76 	}
77 
78 	if (trace->nr_entries < trace->max_entries)
79 		trace->entries[trace->nr_entries++] = addr;
80 }
81 
82 static const struct stacktrace_ops save_stack_ops_nosched = {
83 	.warning = save_stack_warning,
84 	.warning_symbol = save_stack_warning_symbol,
85 	.stack = save_stack_stack,
86 	.address = save_stack_address_nosched,
87 };
88 
89 void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
90 {
91 	unsigned long *sp = (unsigned long *)tsk->thread.sp;
92 
93 	unwind_stack(current, NULL, sp,  &save_stack_ops_nosched, trace);
94 }
95 EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
96