arch/s390/kernel/stacktrace.c

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