xref: /linux/tools/perf/bench/evlist-open-close.c (revision 473f6c8f437b049f8ec015d57cd59bb983b1d85c)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <errno.h>
3 #include <inttypes.h>
4 #include <stdio.h>
5 #include <stdlib.h>
6 #include <limits.h>
7 #include "bench.h"
8 #include "../util/debug.h"
9 #include "../util/stat.h"
10 #include "../util/evlist.h"
11 #include "../util/evsel.h"
12 #include "../util/strbuf.h"
13 #include "../util/record.h"
14 #include "../util/parse-events.h"
15 #include "internal/threadmap.h"
16 #include "internal/cpumap.h"
17 #include <linux/perf_event.h>
18 #include <linux/kernel.h>
19 #include <linux/time64.h>
20 #include <linux/string.h>
21 #include <subcmd/parse-options.h>
22 
23 #define MMAP_FLUSH_DEFAULT 1
24 
25 static int iterations = 100;
26 static int nr_events = 1;
27 static const char *event_string = "dummy";
28 
29 static inline u64 timeval2usec(struct timeval *tv)
30 {
31 	return tv->tv_sec * USEC_PER_SEC + tv->tv_usec;
32 }
33 
34 static struct record_opts opts = {
35 	.sample_time	     = true,
36 	.mmap_pages	     = UINT_MAX,
37 	.user_freq	     = UINT_MAX,
38 	.user_interval	     = ULLONG_MAX,
39 	.freq		     = 4000,
40 	.target		     = {
41 		.uses_mmap   = true,
42 		.default_per_cpu = true,
43 	},
44 	.mmap_flush          = MMAP_FLUSH_DEFAULT,
45 	.nr_threads_synthesize = 1,
46 	.ctl_fd              = -1,
47 	.ctl_fd_ack          = -1,
48 };
49 
50 static int evlist__count_evsel_fds(struct evlist *evlist)
51 {
52 	struct evsel *evsel;
53 	int cnt = 0;
54 
55 	evlist__for_each_entry(evlist, evsel)
56 		cnt += evsel->core.threads->nr * perf_cpu_map__nr(evsel->core.cpus);
57 
58 	return cnt;
59 }
60 
61 static struct evlist *bench__create_evlist(char *evstr, const char *uid_str)
62 {
63 	struct parse_events_error err;
64 	struct evlist *evlist = evlist__new();
65 	int ret;
66 
67 	if (!evlist) {
68 		pr_err("Not enough memory to create evlist\n");
69 		return NULL;
70 	}
71 
72 	parse_events_error__init(&err);
73 	ret = parse_events(evlist, evstr, &err);
74 	if (ret) {
75 		parse_events_error__print(&err, evstr);
76 		parse_events_error__exit(&err);
77 		pr_err("Run 'perf list' for a list of valid events\n");
78 		ret = 1;
79 		goto out_put_evlist;
80 	}
81 	parse_events_error__exit(&err);
82 	if (uid_str) {
83 		uid_t uid = parse_uid(uid_str);
84 
85 		if (uid == UINT_MAX) {
86 			pr_err("Invalid User: %s", uid_str);
87 			ret = -EINVAL;
88 			goto out_put_evlist;
89 		}
90 		ret = parse_uid_filter(evlist, uid);
91 		if (ret)
92 			goto out_put_evlist;
93 	}
94 	ret = evlist__create_maps(evlist, &opts.target);
95 	if (ret < 0) {
96 		pr_err("Not enough memory to create thread/cpu maps\n");
97 		goto out_put_evlist;
98 	}
99 
100 	evlist__config(evlist, &opts, NULL);
101 
102 	return evlist;
103 
104 out_put_evlist:
105 	evlist__put(evlist);
106 	return NULL;
107 }
108 
109 static int bench__do_evlist_open_close(struct evlist *evlist)
110 {
111 	char sbuf[STRERR_BUFSIZE];
112 	int err = evlist__open(evlist);
113 
114 	if (err < 0) {
115 		pr_err("evlist__open: %s\n", str_error_r(errno, sbuf, sizeof(sbuf)));
116 		return err;
117 	}
118 
119 	err = evlist__do_mmap(evlist, opts.mmap_pages);
120 	if (err < 0) {
121 		pr_err("evlist__mmap: %s\n", str_error_r(errno, sbuf, sizeof(sbuf)));
122 		return err;
123 	}
124 
125 	evlist__enable(evlist);
126 	evlist__disable(evlist);
127 	evlist__do_munmap(evlist);
128 	evlist__close(evlist);
129 
130 	return 0;
131 }
132 
133 static int bench_evlist_open_close__run(char *evstr, const char *uid_str)
134 {
135 	// used to print statistics only
136 	struct evlist *evlist = bench__create_evlist(evstr, uid_str);
137 	double time_average, time_stddev;
138 	struct timeval start, end, diff;
139 	struct stats time_stats;
140 	u64 runtime_us;
141 	int i, err;
142 
143 	if (!evlist)
144 		return -ENOMEM;
145 
146 	init_stats(&time_stats);
147 
148 	printf("  Number of cpus:\t%d\n",
149 	       perf_cpu_map__nr(evlist__core(evlist)->user_requested_cpus));
150 	printf("  Number of threads:\t%d\n", evlist__core(evlist)->threads->nr);
151 	printf("  Number of events:\t%d (%d fds)\n",
152 		evlist__nr_entries(evlist), evlist__count_evsel_fds(evlist));
153 	printf("  Number of iterations:\t%d\n", iterations);
154 
155 	evlist__put(evlist);
156 
157 	for (i = 0; i < iterations; i++) {
158 		pr_debug("Started iteration %d\n", i);
159 		evlist = bench__create_evlist(evstr, uid_str);
160 		if (!evlist)
161 			return -ENOMEM;
162 
163 		gettimeofday(&start, NULL);
164 		err = bench__do_evlist_open_close(evlist);
165 		if (err) {
166 			evlist__put(evlist);
167 			return err;
168 		}
169 
170 		gettimeofday(&end, NULL);
171 		timersub(&end, &start, &diff);
172 		runtime_us = timeval2usec(&diff);
173 		update_stats(&time_stats, runtime_us);
174 
175 		evlist__put(evlist);
176 		pr_debug("Iteration %d took:\t%" PRIu64 "us\n", i, runtime_us);
177 	}
178 
179 	time_average = avg_stats(&time_stats);
180 	time_stddev = stddev_stats(&time_stats);
181 	printf("  Average open-close took: %.3f usec (+- %.3f usec)\n", time_average, time_stddev);
182 
183 	return 0;
184 }
185 
186 static char *bench__repeat_event_string(const char *evstr, int n)
187 {
188 	char sbuf[STRERR_BUFSIZE];
189 	struct strbuf buf;
190 	int i, str_size = strlen(evstr),
191 	    final_size = str_size * n + n,
192 	    err = strbuf_init(&buf, final_size);
193 
194 	if (err) {
195 		pr_err("strbuf_init: %s\n", str_error_r(err, sbuf, sizeof(sbuf)));
196 		goto out_error;
197 	}
198 
199 	for (i = 0; i < n; i++) {
200 		err = strbuf_add(&buf, evstr, str_size);
201 		if (err) {
202 			pr_err("strbuf_add: %s\n", str_error_r(err, sbuf, sizeof(sbuf)));
203 			goto out_error;
204 		}
205 
206 		err = strbuf_addch(&buf, i == n-1 ? '\0' : ',');
207 		if (err) {
208 			pr_err("strbuf_addch: %s\n", str_error_r(err, sbuf, sizeof(sbuf)));
209 			goto out_error;
210 		}
211 	}
212 
213 	return strbuf_detach(&buf, NULL);
214 
215 out_error:
216 	strbuf_release(&buf);
217 	return NULL;
218 }
219 
220 
221 int bench_evlist_open_close(int argc, const char **argv)
222 {
223 	const char *uid_str = NULL;
224 	const struct option options[] = {
225 		OPT_STRING('e', "event", &event_string, "event",
226 			   "event selector. use 'perf list' to list available events"),
227 		OPT_INTEGER('n', "nr-events", &nr_events,
228 			    "number of dummy events to create (default 1). If used with -e, it clones those events n times (1 = no change)"),
229 		OPT_INTEGER('i', "iterations", &iterations,
230 			    "Number of iterations used to compute average (default=100)"),
231 		OPT_BOOLEAN('a', "all-cpus", &opts.target.system_wide,
232 			    "system-wide collection from all CPUs"),
233 		OPT_STRING('C', "cpu", &opts.target.cpu_list, "cpu",
234 			   "list of cpus where to open events"),
235 		OPT_STRING('p', "pid", &opts.target.pid, "pid",
236 			   "record events on existing process id"),
237 		OPT_STRING('t', "tid", &opts.target.tid, "tid",
238 			   "record events on existing thread id"),
239 		OPT_STRING('u', "uid", &uid_str, "user", "user to profile"),
240 		OPT_BOOLEAN(0, "per-thread", &opts.target.per_thread, "use per-thread mmaps"),
241 		OPT_END()
242 	};
243 	const char *const bench_usage[] = {
244 		"perf bench internals evlist-open-close <options>",
245 		NULL
246 	};
247 	char *evstr, errbuf[BUFSIZ];
248 	int err;
249 
250 	argc = parse_options(argc, argv, options, bench_usage, 0);
251 	if (argc) {
252 		usage_with_options(bench_usage, options);
253 		exit(EXIT_FAILURE);
254 	}
255 
256 	err = target__validate(&opts.target);
257 	if (err) {
258 		target__strerror(&opts.target, err, errbuf, sizeof(errbuf));
259 		pr_err("%s\n", errbuf);
260 		goto out;
261 	}
262 
263 	/* Enable ignoring missing threads when -p option is defined. */
264 	opts.ignore_missing_thread = opts.target.pid;
265 
266 	evstr = bench__repeat_event_string(event_string, nr_events);
267 	if (!evstr) {
268 		err = -ENOMEM;
269 		goto out;
270 	}
271 
272 	err = bench_evlist_open_close__run(evstr, uid_str);
273 
274 	free(evstr);
275 out:
276 	return err;
277 }
278