How to convert TSC cpu cycles into seconds ?

Amandesi

main()

{

unsigned long long tsc_start, tsc_end;

tsc_start = get_tsc();

// execute some code

tsc_end = get_tsc();

printf("Total time for execution %llu cpu cycles", tsc_end - tsc_start);

printf("Total time in seconds ") ; // How to compute this ?

}

static unsigned long long get_tsc()

{

unsigned long long tsc;

asm volatile ("rdtsc" : "=A" (tsc));

return tsc;

}