LXR linux/arch/nds32/kernel/stacktrace.c

   1// SPDX-License-Identifier: GPL-2.0
   2// Copyright (C) 2005-2017 Andes Technology Corporation
   3
   4#include <linux/sched/debug.h>
   5#include <linux/sched/task_stack.h>
   6#include <linux/stacktrace.h>
   7
   8void save_stack_trace(struct stack_trace *trace)
   9{
  10        save_stack_trace_tsk(current, trace);
  11}
  12EXPORT_SYMBOL_GPL(save_stack_trace);
  13
  14void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
  15{
  16        unsigned long *fpn;
  17        int skip = trace->skip;
  18        int savesched;
  19
  20        if (tsk == current) {
  21                __asm__ __volatile__("\tori\t%0, $fp, #0\n":"=r"(fpn));
  22                savesched = 1;
  23        } else {
  24                fpn = (unsigned long *)thread_saved_fp(tsk);
  25                savesched = 0;
  26        }
  27
  28        while (!kstack_end(fpn) && !((unsigned long)fpn & 0x3)
  29               && (fpn >= (unsigned long *)TASK_SIZE)) {
  30                unsigned long lpp, fpp;
  31
  32                lpp = fpn[-1];
  33                fpp = fpn[FP_OFFSET];
  34                if (!__kernel_text_address(lpp))
  35                        break;
  36
  37                if (savesched || !in_sched_functions(lpp)) {
  38                        if (skip) {
  39                                skip--;
  40                        } else {
  41                                trace->entries[trace->nr_entries++] = lpp;
  42                                if (trace->nr_entries >= trace->max_entries)
  43                                        break;
  44                        }
  45                }
  46                fpn = (unsigned long *)fpp;
  47        }
  48}
  49EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
  50