msr.h

基于组件方式开发操作系统的OSKIT源代码

/*
 * Access to machine-specific registers (available on 586 and better only)
 * Note: the rd* operations modify the parameters directly (without using
 * pointer indirection), this allows gcc to optimize better
 */

#define rdmsr(msr,val1,val2) \
       __asm__ __volatile__("rdmsr" \
			    : "=a" (val1), "=d" (val2) \
			    : "c" (msr))

#define wrmsr(msr,val1,val2) \
     __asm__ __volatile__("wrmsr" \
			  : /* no outputs */ \
			  : "c" (msr), "a" (val1), "d" (val2))

#define rdtsc(low,high) \
     __asm__ __volatile__("rdtsc" : "=a" (low), "=d" (high))

#define rdtscl(low) \
     __asm__ __volatile__ ("rdtsc" : "=a" (low) : : "edx")

#define rdtscll(val) \
     __asm__ __volatile__ ("rdtsc" : "=A" (val))

#define rdpmc(counter,low,high) \
     __asm__ __volatile__("rdpmc" \
			  : "=a" (low), "=d" (high) \
			  : "c" (counter))