| #include <linux/sched.h> |
| #include <linux/sched/debug.h> |
| #include <linux/stacktrace.h> |
| #include <asm/stacktrace.h> |
| |
| void walk_stackframe(unsigned long sp, |
| int (*fn)(unsigned long addr, void *data), |
| void *data) |
| { |
| unsigned long high = ALIGN(sp, THREAD_SIZE); |
| |
| for (; sp <= high - 4; sp += 4) { |
| unsigned long addr = *(unsigned long *) sp; |
| |
| if (!kernel_text_address(addr)) |
| continue; |
| |
| if (fn(addr, data)) |
| break; |
| } |
| } |
| |
| struct stack_trace_data { |
| struct stack_trace *trace; |
| unsigned int no_sched_functions; |
| unsigned int skip; |
| }; |
| |
| #ifdef CONFIG_STACKTRACE |
| |
| static int save_trace(unsigned long addr, void *d) |
| { |
| struct stack_trace_data *data = d; |
| struct stack_trace *trace = data->trace; |
| |
| if (data->no_sched_functions && in_sched_functions(addr)) |
| return 0; |
| |
| if (data->skip) { |
| data->skip--; |
| return 0; |
| } |
| |
| trace->entries[trace->nr_entries++] = addr; |
| |
| return trace->nr_entries >= trace->max_entries; |
| } |
| |
| void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) |
| { |
| struct stack_trace_data data; |
| unsigned long sp; |
| |
| data.trace = trace; |
| data.skip = trace->skip; |
| |
| if (tsk != current) { |
| data.no_sched_functions = 1; |
| sp = tsk->thread.ksp; |
| } else { |
| data.no_sched_functions = 0; |
| sp = rdsp(); |
| } |
| |
| walk_stackframe(sp, save_trace, &data); |
| if (trace->nr_entries < trace->max_entries) |
| trace->entries[trace->nr_entries++] = ULONG_MAX; |
| } |
| |
| void save_stack_trace(struct stack_trace *trace) |
| { |
| save_stack_trace_tsk(current, trace); |
| } |
| EXPORT_SYMBOL_GPL(save_stack_trace); |
| |
| #endif /* CONFIG_STACKTRACE */ |