1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun #include <linux/sched.h>
3*4882a593Smuzhiyun #include <linux/sched/debug.h>
4*4882a593Smuzhiyun #include <linux/stacktrace.h>
5*4882a593Smuzhiyun #include <linux/thread_info.h>
6*4882a593Smuzhiyun #include <linux/ftrace.h>
7*4882a593Smuzhiyun #include <linux/export.h>
8*4882a593Smuzhiyun #include <asm/ptrace.h>
9*4882a593Smuzhiyun #include <asm/stacktrace.h>
10*4882a593Smuzhiyun
11*4882a593Smuzhiyun #include "kstack.h"
12*4882a593Smuzhiyun
__save_stack_trace(struct thread_info * tp,struct stack_trace * trace,bool skip_sched)13*4882a593Smuzhiyun static void __save_stack_trace(struct thread_info *tp,
14*4882a593Smuzhiyun struct stack_trace *trace,
15*4882a593Smuzhiyun bool skip_sched)
16*4882a593Smuzhiyun {
17*4882a593Smuzhiyun unsigned long ksp, fp;
18*4882a593Smuzhiyun #ifdef CONFIG_FUNCTION_GRAPH_TRACER
19*4882a593Smuzhiyun struct task_struct *t;
20*4882a593Smuzhiyun int graph = 0;
21*4882a593Smuzhiyun #endif
22*4882a593Smuzhiyun
23*4882a593Smuzhiyun if (tp == current_thread_info()) {
24*4882a593Smuzhiyun stack_trace_flush();
25*4882a593Smuzhiyun __asm__ __volatile__("mov %%fp, %0" : "=r" (ksp));
26*4882a593Smuzhiyun } else {
27*4882a593Smuzhiyun ksp = tp->ksp;
28*4882a593Smuzhiyun }
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun fp = ksp + STACK_BIAS;
31*4882a593Smuzhiyun #ifdef CONFIG_FUNCTION_GRAPH_TRACER
32*4882a593Smuzhiyun t = tp->task;
33*4882a593Smuzhiyun #endif
34*4882a593Smuzhiyun do {
35*4882a593Smuzhiyun struct sparc_stackf *sf;
36*4882a593Smuzhiyun struct pt_regs *regs;
37*4882a593Smuzhiyun unsigned long pc;
38*4882a593Smuzhiyun
39*4882a593Smuzhiyun if (!kstack_valid(tp, fp))
40*4882a593Smuzhiyun break;
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun sf = (struct sparc_stackf *) fp;
43*4882a593Smuzhiyun regs = (struct pt_regs *) (sf + 1);
44*4882a593Smuzhiyun
45*4882a593Smuzhiyun if (kstack_is_trap_frame(tp, regs)) {
46*4882a593Smuzhiyun if (!(regs->tstate & TSTATE_PRIV))
47*4882a593Smuzhiyun break;
48*4882a593Smuzhiyun pc = regs->tpc;
49*4882a593Smuzhiyun fp = regs->u_regs[UREG_I6] + STACK_BIAS;
50*4882a593Smuzhiyun } else {
51*4882a593Smuzhiyun pc = sf->callers_pc;
52*4882a593Smuzhiyun fp = (unsigned long)sf->fp + STACK_BIAS;
53*4882a593Smuzhiyun }
54*4882a593Smuzhiyun
55*4882a593Smuzhiyun if (trace->skip > 0)
56*4882a593Smuzhiyun trace->skip--;
57*4882a593Smuzhiyun else if (!skip_sched || !in_sched_functions(pc)) {
58*4882a593Smuzhiyun trace->entries[trace->nr_entries++] = pc;
59*4882a593Smuzhiyun #ifdef CONFIG_FUNCTION_GRAPH_TRACER
60*4882a593Smuzhiyun if ((pc + 8UL) == (unsigned long) &return_to_handler) {
61*4882a593Smuzhiyun struct ftrace_ret_stack *ret_stack;
62*4882a593Smuzhiyun ret_stack = ftrace_graph_get_ret_stack(t,
63*4882a593Smuzhiyun graph);
64*4882a593Smuzhiyun if (ret_stack) {
65*4882a593Smuzhiyun pc = ret_stack->ret;
66*4882a593Smuzhiyun if (trace->nr_entries <
67*4882a593Smuzhiyun trace->max_entries)
68*4882a593Smuzhiyun trace->entries[trace->nr_entries++] = pc;
69*4882a593Smuzhiyun graph++;
70*4882a593Smuzhiyun }
71*4882a593Smuzhiyun }
72*4882a593Smuzhiyun #endif
73*4882a593Smuzhiyun }
74*4882a593Smuzhiyun } while (trace->nr_entries < trace->max_entries);
75*4882a593Smuzhiyun }
76*4882a593Smuzhiyun
save_stack_trace(struct stack_trace * trace)77*4882a593Smuzhiyun void save_stack_trace(struct stack_trace *trace)
78*4882a593Smuzhiyun {
79*4882a593Smuzhiyun __save_stack_trace(current_thread_info(), trace, false);
80*4882a593Smuzhiyun }
81*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(save_stack_trace);
82*4882a593Smuzhiyun
save_stack_trace_tsk(struct task_struct * tsk,struct stack_trace * trace)83*4882a593Smuzhiyun void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
84*4882a593Smuzhiyun {
85*4882a593Smuzhiyun struct thread_info *tp = task_thread_info(tsk);
86*4882a593Smuzhiyun
87*4882a593Smuzhiyun __save_stack_trace(tp, trace, true);
88*4882a593Smuzhiyun }
89*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
90