1 /* 2 * Stack trace management functions 3 * 4 * Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com> 5 */ 6 #include <linux/sched.h> 7 #include <linux/stacktrace.h> 8 #include <linux/module.h> 9 #include <asm/stacktrace.h> 10 11 static void save_stack_warning(void *data, char *msg) 12 { 13 } 14 15 static void 16 save_stack_warning_symbol(void *data, char *msg, unsigned long symbol) 17 { 18 } 19 20 static int save_stack_stack(void *data, char *name) 21 { 22 return -1; 23 } 24 25 static void save_stack_address(void *data, unsigned long addr) 26 { 27 struct stack_trace *trace = (struct stack_trace *)data; 28 if (trace->skip > 0) { 29 trace->skip--; 30 return; 31 } 32 if (trace->nr_entries < trace->max_entries) 33 trace->entries[trace->nr_entries++] = addr; 34 } 35 36 static void save_stack_address_nosched(void *data, unsigned long addr) 37 { 38 struct stack_trace *trace = (struct stack_trace *)data; 39 if (in_sched_functions(addr)) 40 return; 41 if (trace->skip > 0) { 42 trace->skip--; 43 return; 44 } 45 if (trace->nr_entries < trace->max_entries) 46 trace->entries[trace->nr_entries++] = addr; 47 } 48 49 static const struct stacktrace_ops save_stack_ops = { 50 .warning = save_stack_warning, 51 .warning_symbol = save_stack_warning_symbol, 52 .stack = save_stack_stack, 53 .address = save_stack_address, 54 }; 55 56 static const struct stacktrace_ops save_stack_ops_nosched = { 57 .warning = save_stack_warning, 58 .warning_symbol = save_stack_warning_symbol, 59 .stack = save_stack_stack, 60 .address = save_stack_address_nosched, 61 }; 62 63 /* 64 * Save stack-backtrace addresses into a stack_trace buffer. 65 */ 66 void save_stack_trace(struct stack_trace *trace) 67 { 68 dump_trace(current, NULL, NULL, &save_stack_ops, trace); 69 if (trace->nr_entries < trace->max_entries) 70 trace->entries[trace->nr_entries++] = ULONG_MAX; 71 } 72 EXPORT_SYMBOL(save_stack_trace); 73 74 void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) 75 { 76 dump_trace(tsk, NULL, NULL, &save_stack_ops_nosched, trace); 77 if (trace->nr_entries < trace->max_entries) 78 trace->entries[trace->nr_entries++] = ULONG_MAX; 79 } 80