arch/sh/kernel/dumpstack.c

   1 /*
   2  *  Copyright (C) 1991, 1992  Linus Torvalds
   3  *  Copyright (C) 2000, 2001, 2002 Andi Kleen, SuSE Labs
   4  *  Copyright (C) 2009  Matt Fleming
   5  *  Copyright (C) 2002 - 2012  Paul Mundt
   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 #include <linux/kallsyms.h>
  12 #include <linux/ftrace.h>
  13 #include <linux/debug_locks.h>
  14 #include <linux/kdebug.h>
  15 #include <linux/export.h>
  16 #include <linux/uaccess.h>
  17 #include <asm/unwinder.h>
  18 #include <asm/stacktrace.h>
  19
  20 void dump_mem(const char *str, unsigned long bottom, unsigned long top)
  21 {
  22         unsigned long p;
  23         int i;
  24
  25         printk("%s(0x%08lx to 0x%08lx)\n", str, bottom, top);
  26
  27         for (p = bottom & ~31; p < top; ) {
  28                 printk("%04lx: ", p & 0xffff);
  29
  30                 for (i = 0; i < 8; i++, p += 4) {
  31                         unsigned int val;
  32
  33                         if (p < bottom || p >= top)
  34                                 printk("         ");
  35                         else {
  36                                 if (__get_user(val, (unsigned int __user *)p)) {
  37                                         printk("\n");
  38                                         return;
  39                                 }
  40                                 printk("%08x ", val);
  41                         }
  42                 }
  43                 printk("\n");
  44         }
  45 }
  46
  47 void printk_address(unsigned long address, int reliable)
  48 {
  49         printk(" [<%p>] %s%pS\n", (void *) address,
  50                         reliable ? "" : "? ", (void *) address);
  51 }
  52
  53 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
  54 static void
  55 print_ftrace_graph_addr(unsigned long addr, void *data,
  56                         const struct stacktrace_ops *ops,
  57                         struct thread_info *tinfo, int *graph)
  58 {
  59         struct task_struct *task = tinfo->task;
  60         unsigned long ret_addr;
  61         int index = task->curr_ret_stack;
  62
  63         if (addr != (unsigned long)return_to_handler)
  64                 return;
  65
  66         if (!task->ret_stack || index < *graph)
  67                 return;
  68
  69         index -= *graph;
  70         ret_addr = task->ret_stack[index].ret;
  71
  72         ops->address(data, ret_addr, 1);
  73
  74         (*graph)++;
  75 }
  76 #else
  77 static inline void
  78 print_ftrace_graph_addr(unsigned long addr, void *data,
  79                         const struct stacktrace_ops *ops,
  80                         struct thread_info *tinfo, int *graph)
  81 { }
  82 #endif
  83
  84 void
  85 stack_reader_dump(struct task_struct *task, struct pt_regs *regs,
  86                   unsigned long *sp, const struct stacktrace_ops *ops,
  87                   void *data)
  88 {
  89         struct thread_info *context;
  90         int graph = 0;
  91
  92         context = (struct thread_info *)
  93                 ((unsigned long)sp & (~(THREAD_SIZE - 1)));
  94
  95         while (!kstack_end(sp)) {
  96                 unsigned long addr = *sp++;
  97
  98                 if (__kernel_text_address(addr)) {
  99                         ops->address(data, addr, 1);
 100
 101                         print_ftrace_graph_addr(addr, data, ops,
 102                                                 context, &graph);
 103                 }
 104         }
 105 }
 106
 107 static int print_trace_stack(void *data, char *name)
 108 {
 109         printk("%s <%s> ", (char *)data, name);
 110         return 0;
 111 }
 112
 113 /*
 114  * Print one address/symbol entries per line.
 115  */
 116 static void print_trace_address(void *data, unsigned long addr, int reliable)
 117 {
 118         printk(data);
 119         printk_address(addr, reliable);
 120 }
 121
 122 static const struct stacktrace_ops print_trace_ops = {
 123         .stack = print_trace_stack,
 124         .address = print_trace_address,
 125 };
 126
 127 void show_trace(struct task_struct *tsk, unsigned long *sp,
 128                 struct pt_regs *regs)
 129 {
 130         if (regs && user_mode(regs))
 131                 return;
 132
 133         printk("\nCall trace:\n");
 134
 135         unwind_stack(tsk, regs, sp, &print_trace_ops, "");
 136
 137         printk("\n");
 138
 139         if (!tsk)
 140                 tsk = current;
 141
 142         debug_show_held_locks(tsk);
 143 }
 144
 145 void show_stack(struct task_struct *tsk, unsigned long *sp)
 146 {
 147         unsigned long stack;
 148
 149         if (!tsk)
 150                 tsk = current;
 151         if (tsk == current)
 152                 sp = (unsigned long *)current_stack_pointer;
 153         else
 154                 sp = (unsigned long *)tsk->thread.sp;
 155
 156         stack = (unsigned long)sp;
 157         dump_mem("Stack: ", stack, THREAD_SIZE +
 158                  (unsigned long)task_stack_page(tsk));
 159         show_trace(tsk, sp, NULL);
 160 }
 161
 162 void dump_stack(void)
 163 {
 164         show_stack(NULL, NULL);
 165 }
 166 EXPORT_SYMBOL(dump_stack);