v86/tests/kvm-unit-tests/x86/tsc.c
2020-07-21 20:10:11 -05:00

48 lines
829 B
C

#include "libcflat.h"
#include "processor.h"
#define CPUID_80000001_EDX_RDTSCP (1 << 27)
int check_cpuid_80000001_edx(unsigned int bit)
{
return (cpuid(0x80000001).d & bit) != 0;
}
void test_wrtsc(u64 t1)
{
u64 t2;
wrtsc(t1);
t2 = rdtsc();
printf("rdtsc after wrtsc(%" PRId64 "): %" PRId64 "\n", t1, t2);
}
void test_rdtscp(u64 aux)
{
u32 ecx;
wrmsr(MSR_TSC_AUX, aux);
rdtscp(&ecx);
report("Test RDTSCP %" PRIu64, ecx == aux, aux);
}
int main()
{
u64 t1, t2;
t1 = rdtsc();
t2 = rdtsc();
printf("rdtsc latency %u\n", (unsigned)(t2 - t1));
test_wrtsc(0);
test_wrtsc(100000000000ull);
if (check_cpuid_80000001_edx(CPUID_80000001_EDX_RDTSCP)) {
test_rdtscp(0);
test_rdtscp(10);
test_rdtscp(0x100);
} else
printf("rdtscp not supported\n");
return report_summary();
}