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	char sbuf[STRERR_BUFSIZE];
26	union perf_event *event;
27	struct perf_evsel *evsel;
28	struct perf_evlist *evlist;
29	struct perf_event_attr attr = {
30		.type = PERF_TYPE_SOFTWARE,
31		.config = clock_id,
32		.sample_type = PERF_SAMPLE_PERIOD,
33		.exclude_kernel = 1,
34		.disabled = 1,
35		.freq = 1,
36	};
37
38	attr.sample_freq = 500;
39
40	evlist = perf_evlist__new();
41	if (evlist == NULL) {
42		pr_debug("perf_evlist__new\n");
43		return -1;
44	}
45
46	evsel = perf_evsel__new(&attr);
47	if (evsel == NULL) {
48		pr_debug("perf_evsel__new\n");
49		goto out_delete_evlist;
50	}
51	perf_evlist__add(evlist, evsel);
52
53	evlist->cpus = cpu_map__dummy_new();
54	evlist->threads = thread_map__new_by_tid(getpid());
55	if (!evlist->cpus || !evlist->threads) {
56		err = -ENOMEM;
57		pr_debug("Not enough memory to create thread/cpu maps\n");
58		goto out_delete_evlist;
59	}
60
61	if (perf_evlist__open(evlist)) {
62		const char *knob = "/proc/sys/kernel/perf_event_max_sample_rate";
63
64		err = -errno;
65		pr_debug("Couldn't open evlist: %s\nHint: check %s, using %" PRIu64 " in this test.\n",
66			 strerror_r(errno, sbuf, sizeof(sbuf)),
67			 knob, (u64)attr.sample_freq);
68		goto out_delete_evlist;
69	}
70
71	err = perf_evlist__mmap(evlist, 128, true);
72	if (err < 0) {
73		pr_debug("failed to mmap event: %d (%s)\n", errno,
74			 strerror_r(errno, sbuf, sizeof(sbuf)));
75		goto out_delete_evlist;
76	}
77
78	perf_evlist__enable(evlist);
79
80	/* collect samples */
81	for (i = 0; i < NR_LOOPS; i++)
82		tmp++;
83
84	perf_evlist__disable(evlist);
85
86	while ((event = perf_evlist__mmap_read(evlist, 0)) != NULL) {
87		struct perf_sample sample;
88
89		if (event->header.type != PERF_RECORD_SAMPLE)
90			goto next_event;
91
92		err = perf_evlist__parse_sample(evlist, event, &sample);
93		if (err < 0) {
94			pr_debug("Error during parse sample\n");
95			goto out_delete_evlist;
96		}
97
98		total_periods += sample.period;
99		nr_samples++;
100next_event:
101		perf_evlist__mmap_consume(evlist, 0);
102	}
103
104	if ((u64) nr_samples == total_periods) {
105		pr_debug("All (%d) samples have period value of 1!\n",
106			 nr_samples);
107		err = -1;
108	}
109
110out_delete_evlist:
111	perf_evlist__delete(evlist);
112	return err;
113}
114
115int test__sw_clock_freq(void)
116{
117	int ret;
118
119	ret = __test__sw_clock_freq(PERF_COUNT_SW_CPU_CLOCK);
120	if (!ret)
121		ret = __test__sw_clock_freq(PERF_COUNT_SW_TASK_CLOCK);
122
123	return ret;
124}
125