1 // SPDX-License-Identifier: GPL-2.0
2 #include <errno.h>
3 #include <inttypes.h>
4 #include <unistd.h>
5 #include <stdlib.h>
6 #include <signal.h>
7 #include <sys/mman.h>
8 #include <linux/compiler.h>
9 #include <linux/string.h>
10
11 #include "tests.h"
12 #include "util/debug.h"
13 #include "util/evsel.h"
14 #include "util/evlist.h"
15 #include "util/cpumap.h"
16 #include "util/mmap.h"
17 #include "util/sample.h"
18 #include "util/thread_map.h"
19 #include <perf/evlist.h>
20 #include <perf/mmap.h>
21
22 #define NR_LOOPS 10000000
23
24 /*
25 * This test will open software clock events (cpu-clock, task-clock)
26 * then check their frequency -> period conversion has no artifact of
27 * setting period to 1 forcefully.
28 */
__test__sw_clock_freq(enum perf_sw_ids clock_id)29 static int __test__sw_clock_freq(enum perf_sw_ids clock_id)
30 {
31 int i, err = -1;
32 volatile int tmp __maybe_unused = 0;
33 u64 total_periods = 0;
34 int nr_samples = 0;
35 char sbuf[STRERR_BUFSIZE];
36 union perf_event *event;
37 struct evsel *evsel;
38 struct evlist *evlist;
39 struct perf_event_attr attr = {
40 .type = PERF_TYPE_SOFTWARE,
41 .config = clock_id,
42 .sample_type = PERF_SAMPLE_PERIOD,
43 .exclude_kernel = 1,
44 .disabled = 1,
45 .freq = 1,
46 };
47 struct perf_cpu_map *cpus = NULL;
48 struct perf_thread_map *threads = NULL;
49 struct mmap *md;
50
51 attr.sample_freq = 500;
52
53 evlist = evlist__new();
54 if (evlist == NULL) {
55 pr_debug("evlist__new\n");
56 return -1;
57 }
58
59 evsel = evsel__new(&attr);
60 if (evsel == NULL) {
61 pr_debug("evsel__new\n");
62 goto out_delete_evlist;
63 }
64 evlist__add(evlist, evsel);
65
66 cpus = perf_cpu_map__new_any_cpu();
67 threads = thread_map__new_by_tid(getpid());
68 if (!cpus || !threads) {
69 err = -ENOMEM;
70 pr_debug("Not enough memory to create thread/cpu maps\n");
71 goto out_delete_evlist;
72 }
73
74 perf_evlist__set_maps(&evlist->core, cpus, threads);
75
76 if (evlist__open(evlist)) {
77 const char *knob = "/proc/sys/kernel/perf_event_max_sample_rate";
78
79 err = -errno;
80 pr_debug("Couldn't open evlist: %s\nHint: check %s, using %" PRIu64 " in this test.\n",
81 str_error_r(errno, sbuf, sizeof(sbuf)),
82 knob, (u64)attr.sample_freq);
83 goto out_delete_evlist;
84 }
85
86 err = evlist__mmap(evlist, 128);
87 if (err < 0) {
88 pr_debug("failed to mmap event: %d (%s)\n", errno,
89 str_error_r(errno, sbuf, sizeof(sbuf)));
90 goto out_delete_evlist;
91 }
92
93 evlist__enable(evlist);
94
95 /* collect samples */
96 for (i = 0; i < NR_LOOPS; i++)
97 tmp++;
98
99 evlist__disable(evlist);
100
101 md = &evlist->mmap[0];
102 if (perf_mmap__read_init(&md->core) < 0)
103 goto out_init;
104
105 while ((event = perf_mmap__read_event(&md->core)) != NULL) {
106 struct perf_sample sample;
107
108 perf_sample__init(&sample, /*all=*/false);
109 if (event->header.type != PERF_RECORD_SAMPLE)
110 goto next_event;
111
112 err = evlist__parse_sample(evlist, event, &sample);
113 if (err < 0) {
114 pr_debug("Error during parse sample\n");
115 perf_sample__exit(&sample);
116 goto out_delete_evlist;
117 }
118
119 total_periods += sample.period;
120 nr_samples++;
121 next_event:
122 perf_mmap__consume(&md->core);
123 perf_sample__exit(&sample);
124 }
125 perf_mmap__read_done(&md->core);
126
127 out_init:
128 if ((u64) nr_samples == total_periods) {
129 pr_debug("All (%d) samples have period value of 1!\n",
130 nr_samples);
131 err = -1;
132 }
133
134 out_delete_evlist:
135 perf_cpu_map__put(cpus);
136 perf_thread_map__put(threads);
137 evlist__delete(evlist);
138 return err;
139 }
140
test__sw_clock_freq(struct test_suite * test __maybe_unused,int subtest __maybe_unused)141 static int test__sw_clock_freq(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
142 {
143 int ret;
144
145 ret = __test__sw_clock_freq(PERF_COUNT_SW_CPU_CLOCK);
146 if (!ret)
147 ret = __test__sw_clock_freq(PERF_COUNT_SW_TASK_CLOCK);
148
149 return ret;
150 }
151
152 DEFINE_SUITE("Software clock events period values", sw_clock_freq);
153