arch/microblaze/kernel/stacktrace.c

   1 /*
   2  * Stack trace support for Microblaze.
   3  *
   4  * Copyright (C) 2009 Michal Simek <monstr@monstr.eu>
   5  * Copyright (C) 2009 PetaLogix
   6  *
   7  * This file is subject to the terms and conditions of the GNU General Public
   8  * License. See the file "COPYING" in the main directory of this archive
   9  * for more details.
  10  */
  11
  12 #include <linux/sched.h>
  13 #include <linux/stacktrace.h>
  14 #include <linux/thread_info.h>
  15 #include <linux/ptrace.h>
  16 #include <linux/module.h>
  17
  18 /* FIXME initial support */
  19 void save_stack_trace(struct stack_trace *trace)
  20 {
  21         unsigned long *sp;
  22         unsigned long addr;
  23         asm("addik %0, r1, 0" : "=r" (sp));
  24
  25         while (!kstack_end(sp)) {
  26                 addr = *sp++;
  27                 if (__kernel_text_address(addr)) {
  28                         if (trace->skip > 0)
  29                                 trace->skip--;
  30                         else
  31                                 trace->entries[trace->nr_entries++] = addr;
  32
  33                         if (trace->nr_entries >= trace->max_entries)
  34                                 break;
  35                 }
  36         }
  37 }
  38 EXPORT_SYMBOL_GPL(save_stack_trace);
  39
  40 void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
  41 {
  42         unsigned int *sp;
  43         unsigned long addr;
  44
  45         struct thread_info *ti = task_thread_info(tsk);
  46
  47         if (tsk == current)
  48                 asm("addik %0, r1, 0" : "=r" (sp));
  49         else
  50                 sp = (unsigned int *)ti->cpu_context.r1;
  51
  52         while (!kstack_end(sp)) {
  53                 addr = *sp++;
  54                 if (__kernel_text_address(addr)) {
  55                         if (trace->skip > 0)
  56                                 trace->skip--;
  57                         else
  58                                 trace->entries[trace->nr_entries++] = addr;
  59
  60                         if (trace->nr_entries >= trace->max_entries)
  61                                 break;
  62                 }
  63         }
  64 }
  65 EXPORT_SYMBOL_GPL(save_stack_trace_tsk);