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