root/include/linux/stringify.h
#ifndef __LINUX_STRINGIFY_H
#define __LINUX_STRINGIFY_H

/* Indirect stringification.  Doing two levels allows the parameter to be a
 * macro itself.  For example, compile with -DFOO=bar, __stringify(FOO)
 * converts to "bar".
 */

#define __stringify_1(x...)     #x
#define __stringify(x...)       __stringify_1(x)

#define FILE_LINE       __FILE__ ":" __stringify(__LINE__)

#endif  /* !__LINUX_STRINGIFY_H */