1#include <unistd.h>
  2#include <stdlib.h>
  3#include <signal.h>
  4#include <sys/mman.h>
  5
  6#include "tests.h"
  7#include "util/evsel.h"
  8#include "util/evlist.h"
  9#include "util/cpumap.h"
 10#include "util/thread_map.h"
 11
 12#define NR_LOOPS  10000000
 13
 14/*
 15 * This test will open software clock events (cpu-clock, task-clock)
 16 * then check their frequency -> period conversion has no artifact of
 17 * setting period to 1 forcefully.
 18 */
 19static int __test__sw_clock_freq(enum perf_sw_ids clock_id)
 20{
 21	int i, err = -1;
 22	volatile int tmp = 0;
 23	u64 total_periods = 0;
 24	int nr_samples = 0;
 25	union perf_event *event;
 26	struct perf_evsel *evsel;
 27	struct perf_evlist *evlist;
 28	struct perf_event_attr attr = {
 29		.type = PERF_TYPE_SOFTWARE,
 30		.config = clock_id,
 31		.sample_type = PERF_SAMPLE_PERIOD,
 32		.exclude_kernel = 1,
 33		.disabled = 1,
 34		.freq = 1,
 35	};
 36
 37	attr.sample_freq = 500;
 38
 39	evlist = perf_evlist__new();
 40	if (evlist == NULL) {
 41		pr_debug("perf_evlist__new\n");
 42		return -1;
 43	}
 44
 45	evsel = perf_evsel__new(&attr);
 46	if (evsel == NULL) {
 47		pr_debug("perf_evsel__new\n");
 48		goto out_delete_evlist;
 49	}
 50	perf_evlist__add(evlist, evsel);
 51
 52	evlist->cpus = cpu_map__dummy_new();
 53	evlist->threads = thread_map__new_by_tid(getpid());
 54	if (!evlist->cpus || !evlist->threads) {
 55		err = -ENOMEM;
 56		pr_debug("Not enough memory to create thread/cpu maps\n");
 57		goto out_delete_evlist;
 58	}
 59
 60	if (perf_evlist__open(evlist)) {
 61		const char *knob = "/proc/sys/kernel/perf_event_max_sample_rate";
 62
 63		err = -errno;
 64		pr_debug("Couldn't open evlist: %s\nHint: check %s, using %" PRIu64 " in this test.\n",
 65			 strerror(errno), knob, (u64)attr.sample_freq);
 66		goto out_delete_evlist;
 67	}
 68
 69	err = perf_evlist__mmap(evlist, 128, true);
 70	if (err < 0) {
 71		pr_debug("failed to mmap event: %d (%s)\n", errno,
 72			 strerror(errno));
 73		goto out_delete_evlist;
 74	}
 75
 76	perf_evlist__enable(evlist);
 77
 78	/* collect samples */
 79	for (i = 0; i < NR_LOOPS; i++)
 80		tmp++;
 81
 82	perf_evlist__disable(evlist);
 83
 84	while ((event = perf_evlist__mmap_read(evlist, 0)) != NULL) {
 85		struct perf_sample sample;
 86
 87		if (event->header.type != PERF_RECORD_SAMPLE)
 88			goto next_event;
 89
 90		err = perf_evlist__parse_sample(evlist, event, &sample);
 91		if (err < 0) {
 92			pr_debug("Error during parse sample\n");
 93			goto out_delete_evlist;
 94		}
 95
 96		total_periods += sample.period;
 97		nr_samples++;
 98next_event:
 99		perf_evlist__mmap_consume(evlist, 0);
100	}
101
102	if ((u64) nr_samples == total_periods) {
103		pr_debug("All (%d) samples have period value of 1!\n",
104			 nr_samples);
105		err = -1;
106	}
107
108out_delete_evlist:
109	perf_evlist__delete(evlist);
110	return err;
111}
112
113int test__sw_clock_freq(void)
114{
115	int ret;
116
117	ret = __test__sw_clock_freq(PERF_COUNT_SW_CPU_CLOCK);
118	if (!ret)
119		ret = __test__sw_clock_freq(PERF_COUNT_SW_TASK_CLOCK);
120
121	return ret;
122}