diff options
Diffstat (limited to 'tools/testing/selftests/intel_pstate/aperf.c')
-rw-r--r-- | tools/testing/selftests/intel_pstate/aperf.c | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/tools/testing/selftests/intel_pstate/aperf.c b/tools/testing/selftests/intel_pstate/aperf.c new file mode 100644 index 000000000..f6cd03a87 --- /dev/null +++ b/tools/testing/selftests/intel_pstate/aperf.c @@ -0,0 +1,83 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <math.h> +#include <unistd.h> +#include <stdio.h> +#include <stdlib.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <sys/timeb.h> +#include <sched.h> +#include <errno.h> +#include <string.h> +#include "../kselftest.h" + +void usage(char *name) { + printf ("Usage: %s cpunum\n", name); +} + +int main(int argc, char **argv) { + unsigned int i, cpu, fd; + char msr_file_name[64]; + long long tsc, old_tsc, new_tsc; + long long aperf, old_aperf, new_aperf; + long long mperf, old_mperf, new_mperf; + struct timeb before, after; + long long int start, finish, total; + cpu_set_t cpuset; + + if (argc != 2) { + usage(argv[0]); + return 1; + } + + errno = 0; + cpu = strtol(argv[1], (char **) NULL, 10); + + if (errno) { + usage(argv[0]); + return 1; + } + + sprintf(msr_file_name, "/dev/cpu/%d/msr", cpu); + fd = open(msr_file_name, O_RDONLY); + + if (fd == -1) { + printf("/dev/cpu/%d/msr: %s\n", cpu, strerror(errno)); + return KSFT_SKIP; + } + + CPU_ZERO(&cpuset); + CPU_SET(cpu, &cpuset); + + if (sched_setaffinity(0, sizeof(cpu_set_t), &cpuset)) { + perror("Failed to set cpu affinity"); + return 1; + } + + ftime(&before); + pread(fd, &old_tsc, sizeof(old_tsc), 0x10); + pread(fd, &old_aperf, sizeof(old_mperf), 0xe7); + pread(fd, &old_mperf, sizeof(old_aperf), 0xe8); + + for (i=0; i<0x8fffffff; i++) { + sqrt(i); + } + + ftime(&after); + pread(fd, &new_tsc, sizeof(new_tsc), 0x10); + pread(fd, &new_aperf, sizeof(new_mperf), 0xe7); + pread(fd, &new_mperf, sizeof(new_aperf), 0xe8); + + tsc = new_tsc-old_tsc; + aperf = new_aperf-old_aperf; + mperf = new_mperf-old_mperf; + + start = before.time*1000 + before.millitm; + finish = after.time*1000 + after.millitm; + total = finish - start; + + printf("runTime: %4.2f\n", 1.0*total/1000); + printf("freq: %7.0f\n", tsc / (1.0*aperf / (1.0 * mperf)) / total); + return 0; +} |