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

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * arch/sh/kernel/stacktrace.c
   4 *
   5 * Stack trace management functions
   6 *
   7 *  Copyright (C) 2006 - 2008  Paul Mundt
   8 */
   9#include <linux/sched.h>
  10#include <linux/sched/debug.h>
  11#include <linux/stacktrace.h>
  12#include <linux/thread_info.h>
  13#include <linux/module.h>
  14#include <asm/unwinder.h>
  15#include <asm/ptrace.h>
  16#include <asm/stacktrace.h>
  17
  18static int save_stack_stack(void *data, char *name)
  19{
  20        return 0;
  21}
  22
  23/*
  24 * Save stack-backtrace addresses into a stack_trace buffer.
  25 */
  26static void save_stack_address(void *data, unsigned long addr, int reliable)
  27{
  28        struct stack_trace *trace = data;
  29
  30        if (!reliable)
  31                return;
  32
  33        if (trace->skip > 0) {
  34                trace->skip--;
  35                return;
  36        }
  37
  38        if (trace->nr_entries < trace->max_entries)
  39                trace->entries[trace->nr_entries++] = addr;
  40}
  41
  42static const struct stacktrace_ops save_stack_ops = {
  43        .stack = save_stack_stack,
  44        .address = save_stack_address,
  45};
  46
  47void save_stack_trace(struct stack_trace *trace)
  48{
  49        unsigned long *sp = (unsigned long *)current_stack_pointer;
  50
  51        unwind_stack(current, NULL, sp,  &save_stack_ops, trace);
  52}
  53EXPORT_SYMBOL_GPL(save_stack_trace);
  54
  55static void
  56save_stack_address_nosched(void *data, unsigned long addr, int reliable)
  57{
  58        struct stack_trace *trace = (struct stack_trace *)data;
  59
  60        if (!reliable)
  61                return;
  62
  63        if (in_sched_functions(addr))
  64                return;
  65
  66        if (trace->skip > 0) {
  67                trace->skip--;
  68                return;
  69        }
  70
  71        if (trace->nr_entries < trace->max_entries)
  72                trace->entries[trace->nr_entries++] = addr;
  73}
  74
  75static const struct stacktrace_ops save_stack_ops_nosched = {
  76        .stack = save_stack_stack,
  77        .address = save_stack_address_nosched,
  78};
  79
  80void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
  81{
  82        unsigned long *sp = (unsigned long *)tsk->thread.sp;
  83
  84        unwind_stack(current, NULL, sp,  &save_stack_ops_nosched, trace);
  85}
  86EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
  87