LXR linux/arch/s390/kernel/stacktrace.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Stack trace management functions
   4 *
   5 *  Copyright IBM Corp. 2006
   6 *  Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
   7 */
   8
   9#include <linux/sched.h>
  10#include <linux/sched/debug.h>
  11#include <linux/stacktrace.h>
  12#include <linux/kallsyms.h>
  13#include <linux/export.h>
  14
  15static int __save_address(void *data, unsigned long address, int nosched)
  16{
  17        struct stack_trace *trace = data;
  18
  19        if (nosched && in_sched_functions(address))
  20                return 0;
  21        if (trace->skip > 0) {
  22                trace->skip--;
  23                return 0;
  24        }
  25        if (trace->nr_entries < trace->max_entries) {
  26                trace->entries[trace->nr_entries++] = address;
  27                return 0;
  28        }
  29        return 1;
  30}
  31
  32static int save_address(void *data, unsigned long address, int reliable)
  33{
  34        return __save_address(data, address, 0);
  35}
  36
  37static int save_address_nosched(void *data, unsigned long address, int reliable)
  38{
  39        return __save_address(data, address, 1);
  40}
  41
  42void save_stack_trace(struct stack_trace *trace)
  43{
  44        unsigned long sp;
  45
  46        sp = current_stack_pointer();
  47        dump_trace(save_address, trace, NULL, sp);
  48        if (trace->nr_entries < trace->max_entries)
  49                trace->entries[trace->nr_entries++] = ULONG_MAX;
  50}
  51EXPORT_SYMBOL_GPL(save_stack_trace);
  52
  53void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
  54{
  55        unsigned long sp;
  56
  57        sp = tsk->thread.ksp;
  58        if (tsk == current)
  59                sp = current_stack_pointer();
  60        dump_trace(save_address_nosched, trace, tsk, sp);
  61        if (trace->nr_entries < trace->max_entries)
  62                trace->entries[trace->nr_entries++] = ULONG_MAX;
  63}
  64EXPORT_SYMBOL_GPL(save_stack_trace_tsk);
  65
  66void save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace)
  67{
  68        unsigned long sp;
  69
  70        sp = kernel_stack_pointer(regs);
  71        dump_trace(save_address, trace, NULL, sp);
  72        if (trace->nr_entries < trace->max_entries)
  73                trace->entries[trace->nr_entries++] = ULONG_MAX;
  74}
  75EXPORT_SYMBOL_GPL(save_stack_trace_regs);
  76