File size: 1,643 Bytes
3459b20 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 | // Copyright (c) 2022 Victor Suarez Rovere <suarezvictor@gmail.com>
// Code portions Copyright (c) 2018-2020 Ondrej Čerman with MIT License
#include <stdio.h>
#include <math.h>
#include <unistd.h>
#include <fcntl.h>
#define SYSFS_DIR_CPUS "/sys/devices/system/cpu"
static int msr_file;
static int open_msr(short devid) {
char msr_path[20];
sprintf(msr_path, "/dev/cpu/%d/msr", devid);
return open(msr_path, O_RDONLY);
}
static bool read_msr(int file, unsigned index, unsigned long *data) {
if (file < 0)
return false;
return pread(file, data, sizeof *data, index) == sizeof *data;
}
double get_energy_unit() {
unsigned long data;
// AMD OSRR: page 139 - MSRC001_0299
if (!read_msr(msr_file, 0xC0010299, &data))
return 0.0;
return pow(1.0/2.0, (double)((data >> 8) & 0x1F));
}
unsigned long get_package_energy() {
unsigned long data;
// AMD OSRR: page 139 - MSRC001_029B
if (!read_msr(msr_file, 0xC001029B, &data))
return 0;
return data;
}
bool power_init()
{
const short cpuid = 0;
msr_file = open_msr(cpuid);
return msr_file >= 0;
}
#ifndef POWER_BENCH
int main()
{
if(!power_init())
{
perror("Cannot open MSR file. Try using sudo and have the msr module loaded. Error");
exit(1);
}
double unit = get_energy_unit();
unsigned long e0 = get_package_energy();
const unsigned interval_us = 500*1000;
for(;;)
{
usleep(interval_us);
unsigned long e1 = get_package_energy();
long energy = e1 - e0;
e0 = e1;
printf("package energy: %f watts\n", energy*unit/(interval_us*1e-6));
}
return 0;
}
#endif
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