1 // SPDX-License-Identifier: GPL-2.0
2 #include <math.h>
3 #include <unistd.h>
4 #include <stdio.h>
5 #include <stdlib.h>
6 #include <sys/types.h>
7 #include <sys/stat.h>
8 #include <fcntl.h>
9 #include <sys/timeb.h>
10 #include <sched.h>
11 #include <errno.h>
12
13
main(int argc,char ** argv)14 int main(int argc, char **argv) {
15 int cpu, fd;
16 long long msr;
17 char msr_file_name[64];
18
19 if (argc != 2)
20 return 1;
21
22 errno = 0;
23 cpu = strtol(argv[1], (char **) NULL, 10);
24
25 if (errno)
26 return 1;
27
28 sprintf(msr_file_name, "/dev/cpu/%d/msr", cpu);
29 fd = open(msr_file_name, O_RDONLY);
30
31 if (fd == -1) {
32 perror("Failed to open");
33 return 1;
34 }
35
36 pread(fd, &msr, sizeof(msr), 0x199);
37
38 printf("msr 0x199: 0x%llx\n", msr);
39 return 0;
40 }
41