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 20static void save_stack_warning(void *data, char *msg) 21{ 22} 23 24static void 25save_stack_warning_symbol(void *data, char *msg, unsigned long symbol) 26{ 27} 28 29static 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 */ 37static 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 53static 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 60void 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 if (trace->nr_entries < trace->max_entries) 66 trace->entries[trace->nr_entries++] = ULONG_MAX; 67} 68EXPORT_SYMBOL_GPL(save_stack_trace); 69 70static void 71save_stack_address_nosched(void *data, unsigned long addr, int reliable) 72{ 73 struct stack_trace *trace = (struct stack_trace *)data; 74 75 if (!reliable) 76 return; 77 78 if (in_sched_functions(addr)) 79 return; 80 81 if (trace->skip > 0) { 82 trace->skip--; 83 return; 84 } 85 86 if (trace->nr_entries < trace->max_entries) 87 trace->entries[trace->nr_entries++] = addr; 88} 89 90static const struct stacktrace_ops save_stack_ops_nosched = { 91 .warning = save_stack_warning, 92 .warning_symbol = save_stack_warning_symbol, 93 .stack = save_stack_stack, 94 .address = save_stack_address_nosched, 95}; 96 97void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) 98{ 99 unsigned long *sp = (unsigned long *)tsk->thread.sp; 100 101 unwind_stack(current, NULL, sp, &save_stack_ops_nosched, trace); 102 if (trace->nr_entries < trace->max_entries) 103 trace->entries[trace->nr_entries++] = ULONG_MAX; 104} 105EXPORT_SYMBOL_GPL(save_stack_trace_tsk); 106