xref: /openbmc/linux/arch/sparc/kernel/stacktrace.c (revision fd589a8f)
1 #include <linux/sched.h>
2 #include <linux/stacktrace.h>
3 #include <linux/thread_info.h>
4 #include <linux/module.h>
5 #include <asm/ptrace.h>
6 #include <asm/stacktrace.h>
7 
8 #include "kstack.h"
9 
10 static void __save_stack_trace(struct thread_info *tp,
11 			       struct stack_trace *trace,
12 			       bool skip_sched)
13 {
14 	unsigned long ksp, fp;
15 
16 	if (tp == current_thread_info()) {
17 		stack_trace_flush();
18 		__asm__ __volatile__("mov %%fp, %0" : "=r" (ksp));
19 	} else {
20 		ksp = tp->ksp;
21 	}
22 
23 	fp = ksp + STACK_BIAS;
24 	do {
25 		struct sparc_stackf *sf;
26 		struct pt_regs *regs;
27 		unsigned long pc;
28 
29 		if (!kstack_valid(tp, fp))
30 			break;
31 
32 		sf = (struct sparc_stackf *) fp;
33 		regs = (struct pt_regs *) (sf + 1);
34 
35 		if (kstack_is_trap_frame(tp, regs)) {
36 			if (!(regs->tstate & TSTATE_PRIV))
37 				break;
38 			pc = regs->tpc;
39 			fp = regs->u_regs[UREG_I6] + STACK_BIAS;
40 		} else {
41 			pc = sf->callers_pc;
42 			fp = (unsigned long)sf->fp + STACK_BIAS;
43 		}
44 
45 		if (trace->skip > 0)
46 			trace->skip--;
47 		else if (!skip_sched || !in_sched_functions(pc))
48 			trace->entries[trace->nr_entries++] = pc;
49 	} while (trace->nr_entries < trace->max_entries);
50 }
51 
52 void save_stack_trace(struct stack_trace *trace)
53 {
54 	__save_stack_trace(current_thread_info(), trace, false);
55 }
56 EXPORT_SYMBOL_GPL(save_stack_trace);
57 
58 void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
59 {
60 	struct thread_info *tp = task_thread_info(tsk);
61 
62 	__save_stack_trace(tp, trace, true);
63 }
64 EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
65