1. 根目录:
2. arch
3. um
4. include
5. asm
6. smp.h

#ifndef __UM_SMP_H
#define __UM_SMP_H

#ifdef CONFIG_SMP

#include "linux/bitops.h"
#include "asm/current.h"
#include "linux/cpumask.h"

#define raw_smp_processor_id() (current_thread->cpu)

#define cpu_logical_map(n) (n)
#define cpu_number_map(n) (n)
extern int hard_smp_processor_id(void);
#define NO_PROC_ID -1

extern int ncpus;


static inline void smp_cpus_done(unsigned int maxcpus)
{
}

extern struct task_struct *idle_threads[NR_CPUS];

#else

#define hard_smp_processor_id()		0

#endif

#endif