blob: d974c0c1c65f34123af8c7d2a63e2fb3e390e9f9 [file] [log] [blame] [edit]
// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2005-2017 Andes Technology Corporation
#include <linux/sched/debug.h>
#include <linux/sched/task_stack.h>
#include <linux/stacktrace.h>
#include <linux/ftrace.h>
void save_stack_trace(struct stack_trace *trace)
{
save_stack_trace_tsk(current, trace);
}
EXPORT_SYMBOL_GPL(save_stack_trace);
void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
{
unsigned long *fpn;
int skip = trace->skip;
int savesched;
int graph_idx = 0;
if (tsk == current) {
__asm__ __volatile__("\tori\t%0, $fp, #0\n":"=r"(fpn));
savesched = 1;
} else {
fpn = (unsigned long *)thread_saved_fp(tsk);
savesched = 0;
}
while (!kstack_end(fpn) && !((unsigned long)fpn & 0x3)
&& (fpn >= (unsigned long *)TASK_SIZE)) {
unsigned long lpp, fpp;
lpp = fpn[LP_OFFSET];
fpp = fpn[FP_OFFSET];
if (!__kernel_text_address(lpp))
break;
else
lpp = ftrace_graph_ret_addr(tsk, &graph_idx, lpp, NULL);
if (savesched || !in_sched_functions(lpp)) {
if (skip) {
skip--;
} else {
trace->entries[trace->nr_entries++] = lpp;
if (trace->nr_entries >= trace->max_entries)
break;
}
}
fpn = (unsigned long *)fpp;
}
}
EXPORT_SYMBOL_GPL(save_stack_trace_tsk);