xref: /linux/tools/perf/bench/evlist-open-close.c (revision a4eb44a6435d6d8f9e642407a4a06f65eb90ca04)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <inttypes.h>
3 #include <stdio.h>
4 #include <stdlib.h>
5 #include <limits.h>
6 #include "bench.h"
7 #include "../util/debug.h"
8 #include "../util/stat.h"
9 #include "../util/evlist.h"
10 #include "../util/evsel.h"
11 #include "../util/strbuf.h"
12 #include "../util/record.h"
13 #include "../util/parse-events.h"
14 #include "internal/threadmap.h"
15 #include "internal/cpumap.h"
16 #include <linux/perf_event.h>
17 #include <linux/kernel.h>
18 #include <linux/time64.h>
19 #include <linux/string.h>
20 #include <subcmd/parse-options.h>
21 
22 #define MMAP_FLUSH_DEFAULT 1
23 
24 static int iterations = 100;
25 static int nr_events = 1;
26 static const char *event_string = "dummy";
27 
28 static inline u64 timeval2usec(struct timeval *tv)
29 {
30 	return tv->tv_sec * USEC_PER_SEC + tv->tv_usec;
31 }
32 
33 static struct record_opts opts = {
34 	.sample_time	     = true,
35 	.mmap_pages	     = UINT_MAX,
36 	.user_freq	     = UINT_MAX,
37 	.user_interval	     = ULLONG_MAX,
38 	.freq		     = 4000,
39 	.target		     = {
40 		.uses_mmap   = true,
41 		.default_per_cpu = true,
42 	},
43 	.mmap_flush          = MMAP_FLUSH_DEFAULT,
44 	.nr_threads_synthesize = 1,
45 	.ctl_fd              = -1,
46 	.ctl_fd_ack          = -1,
47 };
48 
49 static const struct option options[] = {
50 	OPT_STRING('e', "event", &event_string, "event", "event selector. use 'perf list' to list available events"),
51 	OPT_INTEGER('n', "nr-events", &nr_events,
52 		     "number of dummy events to create (default 1). If used with -e, it clones those events n times (1 = no change)"),
53 	OPT_INTEGER('i', "iterations", &iterations, "Number of iterations used to compute average (default=100)"),
54 	OPT_BOOLEAN('a', "all-cpus", &opts.target.system_wide, "system-wide collection from all CPUs"),
55 	OPT_STRING('C', "cpu", &opts.target.cpu_list, "cpu", "list of cpus where to open events"),
56 	OPT_STRING('p', "pid", &opts.target.pid, "pid", "record events on existing process id"),
57 	OPT_STRING('t', "tid", &opts.target.tid, "tid", "record events on existing thread id"),
58 	OPT_STRING('u', "uid", &opts.target.uid_str, "user", "user to profile"),
59 	OPT_BOOLEAN(0, "per-thread", &opts.target.per_thread, "use per-thread mmaps"),
60 	OPT_END()
61 };
62 
63 static const char *const bench_usage[] = {
64 	"perf bench internals evlist-open-close <options>",
65 	NULL
66 };
67 
68 static int evlist__count_evsel_fds(struct evlist *evlist)
69 {
70 	struct evsel *evsel;
71 	int cnt = 0;
72 
73 	evlist__for_each_entry(evlist, evsel)
74 		cnt += evsel->core.threads->nr * perf_cpu_map__nr(evsel->core.cpus);
75 
76 	return cnt;
77 }
78 
79 static struct evlist *bench__create_evlist(char *evstr)
80 {
81 	struct parse_events_error err;
82 	struct evlist *evlist = evlist__new();
83 	int ret;
84 
85 	if (!evlist) {
86 		pr_err("Not enough memory to create evlist\n");
87 		return NULL;
88 	}
89 
90 	parse_events_error__init(&err);
91 	ret = parse_events(evlist, evstr, &err);
92 	if (ret) {
93 		parse_events_error__print(&err, evstr);
94 		parse_events_error__exit(&err);
95 		pr_err("Run 'perf list' for a list of valid events\n");
96 		ret = 1;
97 		goto out_delete_evlist;
98 	}
99 	parse_events_error__exit(&err);
100 	ret = evlist__create_maps(evlist, &opts.target);
101 	if (ret < 0) {
102 		pr_err("Not enough memory to create thread/cpu maps\n");
103 		goto out_delete_evlist;
104 	}
105 
106 	evlist__config(evlist, &opts, NULL);
107 
108 	return evlist;
109 
110 out_delete_evlist:
111 	evlist__delete(evlist);
112 	return NULL;
113 }
114 
115 static int bench__do_evlist_open_close(struct evlist *evlist)
116 {
117 	char sbuf[STRERR_BUFSIZE];
118 	int err = evlist__open(evlist);
119 
120 	if (err < 0) {
121 		pr_err("evlist__open: %s\n", str_error_r(errno, sbuf, sizeof(sbuf)));
122 		return err;
123 	}
124 
125 	err = evlist__mmap(evlist, opts.mmap_pages);
126 	if (err < 0) {
127 		pr_err("evlist__mmap: %s\n", str_error_r(errno, sbuf, sizeof(sbuf)));
128 		return err;
129 	}
130 
131 	evlist__enable(evlist);
132 	evlist__disable(evlist);
133 	evlist__munmap(evlist);
134 	evlist__close(evlist);
135 
136 	return 0;
137 }
138 
139 static int bench_evlist_open_close__run(char *evstr)
140 {
141 	// used to print statistics only
142 	struct evlist *evlist = bench__create_evlist(evstr);
143 	double time_average, time_stddev;
144 	struct timeval start, end, diff;
145 	struct stats time_stats;
146 	u64 runtime_us;
147 	int i, err;
148 
149 	if (!evlist)
150 		return -ENOMEM;
151 
152 	init_stats(&time_stats);
153 
154 	printf("  Number of cpus:\t%d\n", perf_cpu_map__nr(evlist->core.cpus));
155 	printf("  Number of threads:\t%d\n", evlist->core.threads->nr);
156 	printf("  Number of events:\t%d (%d fds)\n",
157 		evlist->core.nr_entries, evlist__count_evsel_fds(evlist));
158 	printf("  Number of iterations:\t%d\n", iterations);
159 
160 	evlist__delete(evlist);
161 
162 	for (i = 0; i < iterations; i++) {
163 		pr_debug("Started iteration %d\n", i);
164 		evlist = bench__create_evlist(evstr);
165 		if (!evlist)
166 			return -ENOMEM;
167 
168 		gettimeofday(&start, NULL);
169 		err = bench__do_evlist_open_close(evlist);
170 		if (err) {
171 			evlist__delete(evlist);
172 			return err;
173 		}
174 
175 		gettimeofday(&end, NULL);
176 		timersub(&end, &start, &diff);
177 		runtime_us = timeval2usec(&diff);
178 		update_stats(&time_stats, runtime_us);
179 
180 		evlist__delete(evlist);
181 		pr_debug("Iteration %d took:\t%" PRIu64 "us\n", i, runtime_us);
182 	}
183 
184 	time_average = avg_stats(&time_stats);
185 	time_stddev = stddev_stats(&time_stats);
186 	printf("  Average open-close took: %.3f usec (+- %.3f usec)\n", time_average, time_stddev);
187 
188 	return 0;
189 }
190 
191 static char *bench__repeat_event_string(const char *evstr, int n)
192 {
193 	char sbuf[STRERR_BUFSIZE];
194 	struct strbuf buf;
195 	int i, str_size = strlen(evstr),
196 	    final_size = str_size * n + n,
197 	    err = strbuf_init(&buf, final_size);
198 
199 	if (err) {
200 		pr_err("strbuf_init: %s\n", str_error_r(err, sbuf, sizeof(sbuf)));
201 		goto out_error;
202 	}
203 
204 	for (i = 0; i < n; i++) {
205 		err = strbuf_add(&buf, evstr, str_size);
206 		if (err) {
207 			pr_err("strbuf_add: %s\n", str_error_r(err, sbuf, sizeof(sbuf)));
208 			goto out_error;
209 		}
210 
211 		err = strbuf_addch(&buf, i == n-1 ? '\0' : ',');
212 		if (err) {
213 			pr_err("strbuf_addch: %s\n", str_error_r(err, sbuf, sizeof(sbuf)));
214 			goto out_error;
215 		}
216 	}
217 
218 	return strbuf_detach(&buf, NULL);
219 
220 out_error:
221 	strbuf_release(&buf);
222 	return NULL;
223 }
224 
225 
226 int bench_evlist_open_close(int argc, const char **argv)
227 {
228 	char *evstr, errbuf[BUFSIZ];
229 	int err;
230 
231 	argc = parse_options(argc, argv, options, bench_usage, 0);
232 	if (argc) {
233 		usage_with_options(bench_usage, options);
234 		exit(EXIT_FAILURE);
235 	}
236 
237 	err = target__validate(&opts.target);
238 	if (err) {
239 		target__strerror(&opts.target, err, errbuf, sizeof(errbuf));
240 		pr_err("%s\n", errbuf);
241 		goto out;
242 	}
243 
244 	err = target__parse_uid(&opts.target);
245 	if (err) {
246 		target__strerror(&opts.target, err, errbuf, sizeof(errbuf));
247 		pr_err("%s", errbuf);
248 		goto out;
249 	}
250 
251 	/* Enable ignoring missing threads when -u/-p option is defined. */
252 	opts.ignore_missing_thread = opts.target.uid != UINT_MAX || opts.target.pid;
253 
254 	evstr = bench__repeat_event_string(event_string, nr_events);
255 	if (!evstr) {
256 		err = -ENOMEM;
257 		goto out;
258 	}
259 
260 	err = bench_evlist_open_close__run(evstr);
261 
262 	free(evstr);
263 out:
264 	return err;
265 }
266