Linux 5.1.15
[linux/fpc-iii.git] / tools / perf / tests / sw-clock.c
blobf9490b23789321cdbb38486b1182baa4a7ea7d9d
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>
9 #include "tests.h"
10 #include "util/evsel.h"
11 #include "util/evlist.h"
12 #include "util/cpumap.h"
13 #include "util/thread_map.h"
15 #define NR_LOOPS 10000000
18 * This test will open software clock events (cpu-clock, task-clock)
19 * then check their frequency -> period conversion has no artifact of
20 * setting period to 1 forcefully.
22 static int __test__sw_clock_freq(enum perf_sw_ids clock_id)
24 int i, err = -1;
25 volatile int tmp = 0;
26 u64 total_periods = 0;
27 int nr_samples = 0;
28 char sbuf[STRERR_BUFSIZE];
29 union perf_event *event;
30 struct perf_evsel *evsel;
31 struct perf_evlist *evlist;
32 struct perf_event_attr attr = {
33 .type = PERF_TYPE_SOFTWARE,
34 .config = clock_id,
35 .sample_type = PERF_SAMPLE_PERIOD,
36 .exclude_kernel = 1,
37 .disabled = 1,
38 .freq = 1,
40 struct cpu_map *cpus;
41 struct thread_map *threads;
42 struct perf_mmap *md;
44 attr.sample_freq = 500;
46 evlist = perf_evlist__new();
47 if (evlist == NULL) {
48 pr_debug("perf_evlist__new\n");
49 return -1;
52 evsel = perf_evsel__new(&attr);
53 if (evsel == NULL) {
54 pr_debug("perf_evsel__new\n");
55 goto out_delete_evlist;
57 perf_evlist__add(evlist, evsel);
59 cpus = cpu_map__dummy_new();
60 threads = thread_map__new_by_tid(getpid());
61 if (!cpus || !threads) {
62 err = -ENOMEM;
63 pr_debug("Not enough memory to create thread/cpu maps\n");
64 goto out_free_maps;
67 perf_evlist__set_maps(evlist, cpus, threads);
69 cpus = NULL;
70 threads = NULL;
72 if (perf_evlist__open(evlist)) {
73 const char *knob = "/proc/sys/kernel/perf_event_max_sample_rate";
75 err = -errno;
76 pr_debug("Couldn't open evlist: %s\nHint: check %s, using %" PRIu64 " in this test.\n",
77 str_error_r(errno, sbuf, sizeof(sbuf)),
78 knob, (u64)attr.sample_freq);
79 goto out_delete_evlist;
82 err = perf_evlist__mmap(evlist, 128);
83 if (err < 0) {
84 pr_debug("failed to mmap event: %d (%s)\n", errno,
85 str_error_r(errno, sbuf, sizeof(sbuf)));
86 goto out_delete_evlist;
89 perf_evlist__enable(evlist);
91 /* collect samples */
92 for (i = 0; i < NR_LOOPS; i++)
93 tmp++;
95 perf_evlist__disable(evlist);
97 md = &evlist->mmap[0];
98 if (perf_mmap__read_init(md) < 0)
99 goto out_init;
101 while ((event = perf_mmap__read_event(md)) != NULL) {
102 struct perf_sample sample;
104 if (event->header.type != PERF_RECORD_SAMPLE)
105 goto next_event;
107 err = perf_evlist__parse_sample(evlist, event, &sample);
108 if (err < 0) {
109 pr_debug("Error during parse sample\n");
110 goto out_delete_evlist;
113 total_periods += sample.period;
114 nr_samples++;
115 next_event:
116 perf_mmap__consume(md);
118 perf_mmap__read_done(md);
120 out_init:
121 if ((u64) nr_samples == total_periods) {
122 pr_debug("All (%d) samples have period value of 1!\n",
123 nr_samples);
124 err = -1;
127 out_free_maps:
128 cpu_map__put(cpus);
129 thread_map__put(threads);
130 out_delete_evlist:
131 perf_evlist__delete(evlist);
132 return err;
135 int test__sw_clock_freq(struct test *test __maybe_unused, int subtest __maybe_unused)
137 int ret;
139 ret = __test__sw_clock_freq(PERF_COUNT_SW_CPU_CLOCK);
140 if (!ret)
141 ret = __test__sw_clock_freq(PERF_COUNT_SW_TASK_CLOCK);
143 return ret;