[LTP] [PATCH v13] high_freq_hwp_cap_cppc.c: new test

[Cyril Hrubis]

Hi!
> +#include "tst_test.h"
> +#include "tst_safe_prw.h"
> +
> +#define MSR_HWP_CAPABILITIES	0x771
> +#define HIGHEST_PERF_MASK	0xFF
> +
> +static int nproc;
> +static int fd = -1;
> +static int *mismatch;
> +
> +static void setup(void)
> +{
> +	if (access("/dev/cpu/0/msr", F_OK) == -1)
> +		tst_brk(TCONF | TERRNO, "msr driver not loaded");
> +
> +	if (access("/sys/devices/system/cpu/cpu0/acpi_cppc/highest_perf", F_OK) == -1)
> +		tst_brk(TCONF | TERRNO, "CPPC sysfs not available");
> +
> +	nproc = tst_ncpus_conf();
> +	mismatch = SAFE_MALLOC(nproc * sizeof(int));
> +}
> +
> +static void cleanup(void)
> +{
> +	if (fd != -1)
> +		SAFE_CLOSE(fd);
> +
> +	free(mismatch);
> +}
> +
> +static void run(void)
> +{
> +	bool status = true;
> +	char path[PATH_MAX];
> +
> +	memset(mismatch, 0, nproc * sizeof(*mismatch));
> +
> +	for (int i = 0; i < nproc; i++) {
> +		int online = 1;
> +		unsigned long long msr_highest_perf = 0, sysfs_highest_perf = 0;
> +
> +		if (i) {
> +			snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/online", i);
> +			SAFE_FILE_SCANF(path, "%d", &online);
> +		}
> +
> +		if (!online) {
> +			tst_res(TINFO, "CPU%d offline, skipping", i);
> +			continue;
> +		}
> +
> +		snprintf(path, sizeof(path), "/sys/devices/system/cpu/cpu%d/acpi_cppc/highest_perf", i);
> +		SAFE_FILE_SCANF(path, "%llu", &sysfs_highest_perf);
> +		tst_res(TDEBUG, "%s: %llu", path, sysfs_highest_perf);
> +
> +		snprintf(path, sizeof(path), "/dev/cpu/%d/msr", i);
> +		fd = SAFE_OPEN(path, O_RDONLY);
> +
> +		SAFE_PREAD(1, fd, &msr_highest_perf, sizeof(msr_highest_perf), MSR_HWP_CAPABILITIES);

If I run the test on AMD Ryzen I get EIO here. I suppose that we need to
limit this test to a family of CPUs that match the MSR format we expect.

-- 
Cyril Hrubis
chrubis@suse.cz