arch/sh/kernel/stacktrace.c

   1 /*
   2  * arch/sh/kernel/stacktrace.c
   3  *
   4  * Stack trace management functions
   5  *
   6  *  Copyright (C) 2006  Paul Mundt
   7  *
   8  * This file is subject to the terms and conditions of the GNU General Public
   9  * License.  See the file "COPYING" in the main directory of this archive
  10  * for more details.
  11  */
  12 #include <linux/sched.h>
  13 #include <linux/stacktrace.h>
  14 #include <linux/thread_info.h>
  15 #include <asm/ptrace.h>
  16
  17 /*
  18  * Save stack-backtrace addresses into a stack_trace buffer.
  19  */
  20 void save_stack_trace(struct stack_trace *trace, struct task_struct *task)
  21 {
  22         unsigned long *sp;
  23
  24         if (!task)
  25                 task = current;
  26         if (task == current)
  27                 sp = (unsigned long *)current_stack_pointer;
  28         else
  29                 sp = (unsigned long *)task->thread.sp;
  30
  31         while (!kstack_end(sp)) {
  32                 unsigned long addr = *sp++;
  33
  34                 if (__kernel_text_address(addr)) {
  35                         if (trace->skip > 0)
  36                                 trace->skip--;
  37                         else
  38                                 trace->entries[trace->nr_entries++] = addr;
  39                         if (trace->nr_entries >= trace->max_entries)
  40                                 break;
  41                 }
  42         }
  43 }