Python tool to convert TSC to ms

tsc_elapsed.py

#!/usr/bin/env python3
import sys
import re

def get_tsc_freq_mhz():
    with open('/proc/cpuinfo', 'r') as f:
        for line in f:
            if line.startswith('cpu MHz'):
                match = re.search(r':\s*([\d.]+)', line)
                if match:
                    return float(match.group(1))
    raise RuntimeError("Could not find cpu MHz in /proc/cpuinfo")

def main():
    if len(sys.argv) != 3:
        print(f"Usage: {sys.argv[0]} <start_tsc> <end_tsc>")
        sys.exit(1)

    start_tsc = int(sys.argv[1])
    end_tsc = int(sys.argv[2])
    diff = end_tsc - start_tsc

    freq_mhz = get_tsc_freq_mhz()
    freq_khz = freq_mhz * 1000

    elapsed_ms = diff / freq_khz
    elapsed_us = diff * 1000 / freq_khz

    print(f"TSC start:    {start_tsc}")
    print(f"TSC end:      {end_tsc}")
    print(f"TSC diff:     {diff}")
    print(f"CPU freq:     {freq_mhz:.3f} MHz")
    print(f"Elapsed:      {elapsed_ms:.3f} ms ({elapsed_us:.1f} us)")

if __name__ == '__main__':
    main()