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 | #include <string.h> |
13 | #include <time.h> |
14 | #include "../kselftest.h" |
15 | |
16 | #define MSEC_PER_SEC 1000L |
17 | #define NSEC_PER_MSEC 1000000L |
18 | |
19 | void usage(char *name) { |
20 | printf ("Usage: %s cpunum\n" , name); |
21 | } |
22 | |
23 | int main(int argc, char **argv) { |
24 | unsigned int i, cpu, fd; |
25 | char msr_file_name[64]; |
26 | long long tsc, old_tsc, new_tsc; |
27 | long long aperf, old_aperf, new_aperf; |
28 | long long mperf, old_mperf, new_mperf; |
29 | struct timespec before, after; |
30 | long long int start, finish, total; |
31 | cpu_set_t cpuset; |
32 | |
33 | if (argc != 2) { |
34 | usage(name: argv[0]); |
35 | return 1; |
36 | } |
37 | |
38 | errno = 0; |
39 | cpu = strtol(argv[1], (char **) NULL, 10); |
40 | |
41 | if (errno) { |
42 | usage(name: argv[0]); |
43 | return 1; |
44 | } |
45 | |
46 | sprintf(msr_file_name, "/dev/cpu/%d/msr" , cpu); |
47 | fd = open(msr_file_name, O_RDONLY); |
48 | |
49 | if (fd == -1) { |
50 | printf("/dev/cpu/%d/msr: %s\n" , cpu, strerror(errno)); |
51 | return KSFT_SKIP; |
52 | } |
53 | |
54 | CPU_ZERO(&cpuset); |
55 | CPU_SET(cpu, &cpuset); |
56 | |
57 | if (sched_setaffinity(0, sizeof(cpu_set_t), &cpuset)) { |
58 | perror("Failed to set cpu affinity" ); |
59 | return 1; |
60 | } |
61 | |
62 | if (clock_gettime(CLOCK_MONOTONIC, &before) < 0) { |
63 | perror("clock_gettime" ); |
64 | return 1; |
65 | } |
66 | pread(fd, &old_tsc, sizeof(old_tsc), 0x10); |
67 | pread(fd, &old_aperf, sizeof(old_mperf), 0xe7); |
68 | pread(fd, &old_mperf, sizeof(old_aperf), 0xe8); |
69 | |
70 | for (i=0; i<0x8fffffff; i++) { |
71 | sqrt(i); |
72 | } |
73 | |
74 | if (clock_gettime(CLOCK_MONOTONIC, &after) < 0) { |
75 | perror("clock_gettime" ); |
76 | return 1; |
77 | } |
78 | pread(fd, &new_tsc, sizeof(new_tsc), 0x10); |
79 | pread(fd, &new_aperf, sizeof(new_mperf), 0xe7); |
80 | pread(fd, &new_mperf, sizeof(new_aperf), 0xe8); |
81 | |
82 | tsc = new_tsc-old_tsc; |
83 | aperf = new_aperf-old_aperf; |
84 | mperf = new_mperf-old_mperf; |
85 | |
86 | start = before.tv_sec*MSEC_PER_SEC + before.tv_nsec/NSEC_PER_MSEC; |
87 | finish = after.tv_sec*MSEC_PER_SEC + after.tv_nsec/NSEC_PER_MSEC; |
88 | total = finish - start; |
89 | |
90 | printf("runTime: %4.2f\n" , 1.0*total/MSEC_PER_SEC); |
91 | printf("freq: %7.0f\n" , tsc / (1.0*aperf / (1.0 * mperf)) / total); |
92 | return 0; |
93 | } |
94 | |