#ifndef __UM_DELAY_H#define __UM_DELAY_H #define MILLION 1000000 /* Undefined on purpose */extern void __bad_udelay(void); extern void __udelay(unsigned long usecs);extern void __delay(unsigned long loops); #define udelay(n) ((__builtin_constant_p(n) && (n) > 20000) ? \	__bad_udelay() : __udelay(n)) /* It appears that ndelay is not used at all for UML, and has never been * implemented. */extern void __unimplemented_ndelay(void);#define ndelay(n) __unimplemented_ndelay() #endif