Linux Audio

Check our new training course

Real-Time Linux with PREEMPT_RT training

Feb 18-20, 2025
Register
Loading...
v4.6
 
 
 
  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	struct cpu_map *cpus;
 38	struct thread_map *threads;
 
 39
 40	attr.sample_freq = 500;
 41
 42	evlist = perf_evlist__new();
 43	if (evlist == NULL) {
 44		pr_debug("perf_evlist__new\n");
 45		return -1;
 46	}
 47
 48	evsel = perf_evsel__new(&attr);
 49	if (evsel == NULL) {
 50		pr_debug("perf_evsel__new\n");
 51		goto out_delete_evlist;
 52	}
 53	perf_evlist__add(evlist, evsel);
 54
 55	cpus = cpu_map__dummy_new();
 56	threads = thread_map__new_by_tid(getpid());
 57	if (!cpus || !threads) {
 58		err = -ENOMEM;
 59		pr_debug("Not enough memory to create thread/cpu maps\n");
 60		goto out_free_maps;
 61	}
 62
 63	perf_evlist__set_maps(evlist, cpus, threads);
 64
 65	cpus	= NULL;
 66	threads = NULL;
 67
 68	if (perf_evlist__open(evlist)) {
 69		const char *knob = "/proc/sys/kernel/perf_event_max_sample_rate";
 70
 71		err = -errno;
 72		pr_debug("Couldn't open evlist: %s\nHint: check %s, using %" PRIu64 " in this test.\n",
 73			 strerror_r(errno, sbuf, sizeof(sbuf)),
 74			 knob, (u64)attr.sample_freq);
 75		goto out_delete_evlist;
 76	}
 77
 78	err = perf_evlist__mmap(evlist, 128, true);
 79	if (err < 0) {
 80		pr_debug("failed to mmap event: %d (%s)\n", errno,
 81			 strerror_r(errno, sbuf, sizeof(sbuf)));
 82		goto out_delete_evlist;
 83	}
 84
 85	perf_evlist__enable(evlist);
 86
 87	/* collect samples */
 88	for (i = 0; i < NR_LOOPS; i++)
 89		tmp++;
 90
 91	perf_evlist__disable(evlist);
 92
 93	while ((event = perf_evlist__mmap_read(evlist, 0)) != NULL) {
 
 
 
 
 94		struct perf_sample sample;
 95
 96		if (event->header.type != PERF_RECORD_SAMPLE)
 97			goto next_event;
 98
 99		err = perf_evlist__parse_sample(evlist, event, &sample);
100		if (err < 0) {
101			pr_debug("Error during parse sample\n");
102			goto out_delete_evlist;
103		}
104
105		total_periods += sample.period;
106		nr_samples++;
107next_event:
108		perf_evlist__mmap_consume(evlist, 0);
109	}
 
110
 
111	if ((u64) nr_samples == total_periods) {
112		pr_debug("All (%d) samples have period value of 1!\n",
113			 nr_samples);
114		err = -1;
115	}
116
117out_free_maps:
118	cpu_map__put(cpus);
119	thread_map__put(threads);
120out_delete_evlist:
121	perf_evlist__delete(evlist);
122	return err;
123}
124
125int test__sw_clock_freq(int subtest __maybe_unused)
126{
127	int ret;
128
129	ret = __test__sw_clock_freq(PERF_COUNT_SW_CPU_CLOCK);
130	if (!ret)
131		ret = __test__sw_clock_freq(PERF_COUNT_SW_TASK_CLOCK);
132
133	return ret;
134}
v5.9
  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/string.h>
  9
 10#include "tests.h"
 11#include "util/debug.h"
 12#include "util/evsel.h"
 13#include "util/evlist.h"
 14#include "util/cpumap.h"
 15#include "util/mmap.h"
 16#include "util/thread_map.h"
 17#include <perf/evlist.h>
 18#include <perf/mmap.h>
 19
 20#define NR_LOOPS  10000000
 21
 22/*
 23 * This test will open software clock events (cpu-clock, task-clock)
 24 * then check their frequency -> period conversion has no artifact of
 25 * setting period to 1 forcefully.
 26 */
 27static int __test__sw_clock_freq(enum perf_sw_ids clock_id)
 28{
 29	int i, err = -1;
 30	volatile int tmp = 0;
 31	u64 total_periods = 0;
 32	int nr_samples = 0;
 33	char sbuf[STRERR_BUFSIZE];
 34	union perf_event *event;
 35	struct evsel *evsel;
 36	struct evlist *evlist;
 37	struct perf_event_attr attr = {
 38		.type = PERF_TYPE_SOFTWARE,
 39		.config = clock_id,
 40		.sample_type = PERF_SAMPLE_PERIOD,
 41		.exclude_kernel = 1,
 42		.disabled = 1,
 43		.freq = 1,
 44	};
 45	struct perf_cpu_map *cpus;
 46	struct perf_thread_map *threads;
 47	struct mmap *md;
 48
 49	attr.sample_freq = 500;
 50
 51	evlist = evlist__new();
 52	if (evlist == NULL) {
 53		pr_debug("evlist__new\n");
 54		return -1;
 55	}
 56
 57	evsel = evsel__new(&attr);
 58	if (evsel == NULL) {
 59		pr_debug("evsel__new\n");
 60		goto out_delete_evlist;
 61	}
 62	evlist__add(evlist, evsel);
 63
 64	cpus = perf_cpu_map__dummy_new();
 65	threads = thread_map__new_by_tid(getpid());
 66	if (!cpus || !threads) {
 67		err = -ENOMEM;
 68		pr_debug("Not enough memory to create thread/cpu maps\n");
 69		goto out_free_maps;
 70	}
 71
 72	perf_evlist__set_maps(&evlist->core, cpus, threads);
 73
 74	cpus	= NULL;
 75	threads = NULL;
 76
 77	if (evlist__open(evlist)) {
 78		const char *knob = "/proc/sys/kernel/perf_event_max_sample_rate";
 79
 80		err = -errno;
 81		pr_debug("Couldn't open evlist: %s\nHint: check %s, using %" PRIu64 " in this test.\n",
 82			 str_error_r(errno, sbuf, sizeof(sbuf)),
 83			 knob, (u64)attr.sample_freq);
 84		goto out_delete_evlist;
 85	}
 86
 87	err = evlist__mmap(evlist, 128);
 88	if (err < 0) {
 89		pr_debug("failed to mmap event: %d (%s)\n", errno,
 90			 str_error_r(errno, sbuf, sizeof(sbuf)));
 91		goto out_delete_evlist;
 92	}
 93
 94	evlist__enable(evlist);
 95
 96	/* collect samples */
 97	for (i = 0; i < NR_LOOPS; i++)
 98		tmp++;
 99
100	evlist__disable(evlist);
101
102	md = &evlist->mmap[0];
103	if (perf_mmap__read_init(&md->core) < 0)
104		goto out_init;
105
106	while ((event = perf_mmap__read_event(&md->core)) != NULL) {
107		struct perf_sample sample;
108
109		if (event->header.type != PERF_RECORD_SAMPLE)
110			goto next_event;
111
112		err = perf_evlist__parse_sample(evlist, event, &sample);
113		if (err < 0) {
114			pr_debug("Error during parse sample\n");
115			goto out_delete_evlist;
116		}
117
118		total_periods += sample.period;
119		nr_samples++;
120next_event:
121		perf_mmap__consume(&md->core);
122	}
123	perf_mmap__read_done(&md->core);
124
125out_init:
126	if ((u64) nr_samples == total_periods) {
127		pr_debug("All (%d) samples have period value of 1!\n",
128			 nr_samples);
129		err = -1;
130	}
131
132out_free_maps:
133	perf_cpu_map__put(cpus);
134	perf_thread_map__put(threads);
135out_delete_evlist:
136	evlist__delete(evlist);
137	return err;
138}
139
140int test__sw_clock_freq(struct test *test __maybe_unused, int subtest __maybe_unused)
141{
142	int ret;
143
144	ret = __test__sw_clock_freq(PERF_COUNT_SW_CPU_CLOCK);
145	if (!ret)
146		ret = __test__sw_clock_freq(PERF_COUNT_SW_TASK_CLOCK);
147
148	return ret;
149}