1 /* 2 * Stack trace management functions 3 * 4 * Copyright (C) 2009 Helge Deller <deller@gmx.de> 5 * based on arch/x86/kernel/stacktrace.c by Ingo Molnar <mingo@redhat.com> 6 * and parisc unwind functions by Randolph Chung <tausq@debian.org> 7 * 8 * TODO: Userspace stacktrace (CONFIG_USER_STACKTRACE_SUPPORT) 9 */ 10 #include <linux/module.h> 11 #include <linux/stacktrace.h> 12 13 #include <asm/unwind.h> 14 15 static void dump_trace(struct task_struct *task, struct stack_trace *trace) 16 { 17 struct unwind_frame_info info; 18 19 unwind_frame_init_task(&info, task, NULL); 20 21 /* unwind stack and save entries in stack_trace struct */ 22 trace->nr_entries = 0; 23 while (trace->nr_entries < trace->max_entries) { 24 if (unwind_once(&info) < 0 || info.ip == 0) 25 break; 26 27 if (__kernel_text_address(info.ip)) 28 trace->entries[trace->nr_entries++] = info.ip; 29 } 30 } 31 32 33 /* 34 * Save stack-backtrace addresses into a stack_trace buffer. 35 */ 36 void save_stack_trace(struct stack_trace *trace) 37 { 38 dump_trace(current, trace); 39 if (trace->nr_entries < trace->max_entries) 40 trace->entries[trace->nr_entries++] = ULONG_MAX; 41 } 42 EXPORT_SYMBOL_GPL(save_stack_trace); 43 44 void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) 45 { 46 dump_trace(tsk, trace); 47 if (trace->nr_entries < trace->max_entries) 48 trace->entries[trace->nr_entries++] = ULONG_MAX; 49 } 50 EXPORT_SYMBOL_GPL(save_stack_trace_tsk); 51