lib/dump_stack.c

/*
 * Provide a default dump_stack() function for architectures
 * which don't implement their own.
 */

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/utsname.h>
#include <linux/export.h>

static char dump_stack_arch_desc_str[128];

/**
 * dump_stack_set_arch_desc - set arch-specific str to show with task dumps
 * @fmt: printf-style format string
 * @...: arguments for the format string
 *
 * The configured string will be printed right after utsname during task
 * dumps.  Usually used to add arch-specific system identifiers.  If an
 * arch wants to make use of such an ID string, it should initialize this
 * as soon as possible during boot.
 */
void __init dump_stack_set_arch_desc(const char *fmt, ...)
{
	va_list args;

	va_start(args, fmt);
	vsnprintf(dump_stack_arch_desc_str, sizeof(dump_stack_arch_desc_str),
		  fmt, args);
	va_end(args);
}

/**
 * dump_stack_print_info - print generic debug info for dump_stack()
 * @log_lvl: log level
 *
 * Arch-specific dump_stack() implementations can use this function to
 * print out the same debug information as the generic dump_stack().
 */
void dump_stack_print_info(const char *log_lvl)
{
	printk("%sPid: %d, comm: %.20s %s %s %.*s %s\n",
	       log_lvl, current->pid, current->comm, print_tainted(),
	       init_utsname()->release,
	       (int)strcspn(init_utsname()->version, " "),
	       init_utsname()->version, dump_stack_arch_desc_str);
}

/**
 * dump_stack - dump the current task information and its stack trace
 *
 * Architectures can override this implementation by implementing its own.
 */
void dump_stack(void)
{
	dump_stack_print_info(KERN_DEFAULT);
	show_stack(NULL, NULL);
}
EXPORT_SYMBOL(dump_stack);

/**
 * show_regs_print_info - print generic debug info for show_regs()
 * @log_lvl: log level
 *
 * show_regs() implementations can use this function to print out generic
 * debug information.
 */
void show_regs_print_info(const char *log_lvl)
{
	dump_stack_print_info(log_lvl);

	printk("%sCPU:%d task: %p ti: %p task.ti: %p\n",
	       log_lvl, raw_smp_processor_id(), current, current_thread_info(),
	       task_thread_info(current));
}