/* x86_rdtscp_siewior1.c */

/*
Results:
root@EPU-102054501-AugustToepfer:~/x86_rdtscp# ./x86_rdtscp_siewior1 
CPU  : 0
CPUv2: 0 TS 0x1896116ed97bec
root@EPU-102054501-AugustToepfer:~/x86_rdtscp# ./x86_rdtscp_siewior1 
CPU  : 0
CPUv2: 0 TS 0x189611d176dccc
root@EPU-102054501-AugustToepfer:~/x86_rdtscp# ./x86_rdtscp_siewior1 
CPU  : 0
CPUv2: 0 TS 0x1896121adfeb94
root@EPU-102054501-AugustToepfer:~/x86_rdtscp# ./x86_rdtscp_siewior1 
CPU  : 1
CPUv2: 0 TS 0x189612ab407b60
root@EPU-102054501-AugustToepfer:~/x86_rdtscp# ./x86_rdtscp_siewior1 
CPU  : 1
CPUv2: 0 TS 0x189613730e0678
root@EPU-102054501-AugustToepfer:~/x86_rdtscp# ./x86_rdtscp_siewior1 
CPU  : 0
CPUv2: 0 TS 0x189613e707ae7c
*/

#define _GNU_SOURCE 1

#include <stdio.h>
#include <sched.h>

static inline unsigned int rdtscp(unsigned long long *ts)
{
	unsigned int eax, edx;
	unsigned int cpuid;

	__asm__ __volatile__("rdtscp" : "=a"(eax), "=d"(edx), "=c"(cpuid));
	*ts = ((unsigned long long)edx) << 32 | eax;
	return cpuid;
}

int main(void)
{
	unsigned int cpu;
	unsigned long long tsc;
	unsigned int cpu_v2;

	cpu = sched_getcpu();
	cpu_v2 = rdtscp(&tsc);
	printf("CPU  : %u\n", cpu);
	printf("CPUv2: %u TS 0x%llx\n", cpu_v2, tsc);
	return 0;
}