diff options
Diffstat (limited to 'tools/perf/tests/sw-clock.c')
| -rw-r--r-- | tools/perf/tests/sw-clock.c | 119 | 
1 files changed, 119 insertions, 0 deletions
| diff --git a/tools/perf/tests/sw-clock.c b/tools/perf/tests/sw-clock.c new file mode 100644 index 00000000000..2e41e2d32cc --- /dev/null +++ b/tools/perf/tests/sw-clock.c @@ -0,0 +1,119 @@ +#include <unistd.h> +#include <stdlib.h> +#include <signal.h> +#include <sys/mman.h> + +#include "tests.h" +#include "util/evsel.h" +#include "util/evlist.h" +#include "util/cpumap.h" +#include "util/thread_map.h" + +#define NR_LOOPS  1000000 + +/* + * This test will open software clock events (cpu-clock, task-clock) + * then check their frequency -> period conversion has no artifact of + * setting period to 1 forcefully. + */ +static int __test__sw_clock_freq(enum perf_sw_ids clock_id) +{ +	int i, err = -1; +	volatile int tmp = 0; +	u64 total_periods = 0; +	int nr_samples = 0; +	union perf_event *event; +	struct perf_evsel *evsel; +	struct perf_evlist *evlist; +	struct perf_event_attr attr = { +		.type = PERF_TYPE_SOFTWARE, +		.config = clock_id, +		.sample_type = PERF_SAMPLE_PERIOD, +		.exclude_kernel = 1, +		.disabled = 1, +		.freq = 1, +	}; + +	attr.sample_freq = 10000; + +	evlist = perf_evlist__new(); +	if (evlist == NULL) { +		pr_debug("perf_evlist__new\n"); +		return -1; +	} + +	evsel = perf_evsel__new(&attr, 0); +	if (evsel == NULL) { +		pr_debug("perf_evsel__new\n"); +		goto out_free_evlist; +	} +	perf_evlist__add(evlist, evsel); + +	evlist->cpus = cpu_map__dummy_new(); +	evlist->threads = thread_map__new_by_tid(getpid()); +	if (!evlist->cpus || !evlist->threads) { +		err = -ENOMEM; +		pr_debug("Not enough memory to create thread/cpu maps\n"); +		goto out_delete_maps; +	} + +	perf_evlist__open(evlist); + +	err = perf_evlist__mmap(evlist, 128, true); +	if (err < 0) { +		pr_debug("failed to mmap event: %d (%s)\n", errno, +			 strerror(errno)); +		goto out_close_evlist; +	} + +	perf_evlist__enable(evlist); + +	/* collect samples */ +	for (i = 0; i < NR_LOOPS; i++) +		tmp++; + +	perf_evlist__disable(evlist); + +	while ((event = perf_evlist__mmap_read(evlist, 0)) != NULL) { +		struct perf_sample sample; + +		if (event->header.type != PERF_RECORD_SAMPLE) +			continue; + +		err = perf_evlist__parse_sample(evlist, event, &sample); +		if (err < 0) { +			pr_debug("Error during parse sample\n"); +			goto out_unmap_evlist; +		} + +		total_periods += sample.period; +		nr_samples++; +	} + +	if ((u64) nr_samples == total_periods) { +		pr_debug("All (%d) samples have period value of 1!\n", +			 nr_samples); +		err = -1; +	} + +out_unmap_evlist: +	perf_evlist__munmap(evlist); +out_close_evlist: +	perf_evlist__close(evlist); +out_delete_maps: +	perf_evlist__delete_maps(evlist); +out_free_evlist: +	perf_evlist__delete(evlist); +	return err; +} + +int test__sw_clock_freq(void) +{ +	int ret; + +	ret = __test__sw_clock_freq(PERF_COUNT_SW_CPU_CLOCK); +	if (!ret) +		ret = __test__sw_clock_freq(PERF_COUNT_SW_TASK_CLOCK); + +	return ret; +} |