/* * kernel/stacktrace.c * * Stack trace management functions * *  Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com> */#include <linux/sched.h>#include <linux/kernel.h>#include <linux/export.h>#include <linux/kallsyms.h>#include <linux/stacktrace.h> void print_stack_trace(struct stack_trace *trace, int spaces){	int i; 	if (WARN_ON(!trace->entries))		return; 	for (i = 0; i < trace->nr_entries; i++)		printk("%*c%pS\n", 1 + spaces, ' ', (void *)trace->entries[i]);}EXPORT_SYMBOL_GPL(print_stack_trace); int snprint_stack_trace(char *buf, size_t size,			struct stack_trace *trace, int spaces){	int i;	int generated;	int total = 0; 	if (WARN_ON(!trace->entries))		return 0; 	for (i = 0; i < trace->nr_entries; i++) {		generated = snprintf(buf, size, "%*c%pS\n", 1 + spaces, ' ',				     (void *)trace->entries[i]); 		total += generated; 		/* Assume that generated isn't a negative number */		if (generated >= size) {			buf += size;			size = 0;		} else {			buf += generated;			size -= generated;		}	} 	return total;}EXPORT_SYMBOL_GPL(snprint_stack_trace); /* * Architectures that do not implement save_stack_trace_*() * get these weak aliases and once-per-bootup warnings * (whenever this facility is utilized - for example by procfs): */__weak voidsave_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace){	WARN_ONCE(1, KERN_INFO "save_stack_trace_tsk() not implemented yet.\n");} __weak voidsave_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace){	WARN_ONCE(1, KERN_INFO "save_stack_trace_regs() not implemented yet.\n");} __weak intsave_stack_trace_tsk_reliable(struct task_struct *tsk,			      struct stack_trace *trace){	WARN_ONCE(1, KERN_INFO "save_stack_tsk_reliable() not implemented yet.\n");	return -ENOSYS;}