1 /* 2 * arch/sh/kernel/stacktrace.c 3 * 4 * Stack trace management functions 5 * 6 * Copyright (C) 2006 - 2008 Paul Mundt 7 * 8 * This file is subject to the terms and conditions of the GNU General Public 9 * License. See the file "COPYING" in the main directory of this archive 10 * for more details. 11 */ 12 #include <linux/sched.h> 13 #include <linux/stacktrace.h> 14 #include <linux/thread_info.h> 15 #include <linux/module.h> 16 #include <asm/unwinder.h> 17 #include <asm/ptrace.h> 18 #include <asm/stacktrace.h> 19 20 static void save_stack_warning(void *data, char *msg) 21 { 22 } 23 24 static void 25 save_stack_warning_symbol(void *data, char *msg, unsigned long symbol) 26 { 27 } 28 29 static int save_stack_stack(void *data, char *name) 30 { 31 return 0; 32 } 33 34 /* 35 * Save stack-backtrace addresses into a stack_trace buffer. 36 */ 37 static void save_stack_address(void *data, unsigned long addr, int reliable) 38 { 39 struct stack_trace *trace = data; 40 41 if (!reliable) 42 return; 43 44 if (trace->skip > 0) { 45 trace->skip--; 46 return; 47 } 48 49 if (trace->nr_entries < trace->max_entries) 50 trace->entries[trace->nr_entries++] = addr; 51 } 52 53 static const struct stacktrace_ops save_stack_ops = { 54 .warning = save_stack_warning, 55 .warning_symbol = save_stack_warning_symbol, 56 .stack = save_stack_stack, 57 .address = save_stack_address, 58 }; 59 60 void save_stack_trace(struct stack_trace *trace) 61 { 62 unsigned long *sp = (unsigned long *)current_stack_pointer; 63 64 unwind_stack(current, NULL, sp, &save_stack_ops, trace); 65 } 66 EXPORT_SYMBOL_GPL(save_stack_trace); 67 68 static void 69 save_stack_address_nosched(void *data, unsigned long addr, int reliable) 70 { 71 struct stack_trace *trace = (struct stack_trace *)data; 72 73 if (!reliable) 74 return; 75 76 if (in_sched_functions(addr)) 77 return; 78 79 if (trace->skip > 0) { 80 trace->skip--; 81 return; 82 } 83 84 if (trace->nr_entries < trace->max_entries) 85 trace->entries[trace->nr_entries++] = addr; 86 } 87 88 static const struct stacktrace_ops save_stack_ops_nosched = { 89 .warning = save_stack_warning, 90 .warning_symbol = save_stack_warning_symbol, 91 .stack = save_stack_stack, 92 .address = save_stack_address_nosched, 93 }; 94 95 void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) 96 { 97 unsigned long *sp = (unsigned long *)tsk->thread.sp; 98 99 unwind_stack(current, NULL, sp, &save_stack_ops_nosched, trace); 100 } 101 EXPORT_SYMBOL_GPL(save_stack_trace_tsk); 102